1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
|
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2021 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <validation.h>
#include <arith_uint256.h>
#include <chain.h>
#include <chainparams.h>
#include <checkqueue.h>
#include <consensus/amount.h>
#include <consensus/consensus.h>
#include <consensus/merkle.h>
#include <consensus/tx_check.h>
#include <consensus/tx_verify.h>
#include <consensus/validation.h>
#include <cuckoocache.h>
#include <flatfile.h>
#include <hash.h>
#include <kernel/coinstats.h>
#include <logging.h>
#include <logging/timer.h>
#include <node/blockstorage.h>
#include <node/interface_ui.h>
#include <node/utxo_snapshot.h>
#include <policy/policy.h>
#include <policy/rbf.h>
#include <policy/settings.h>
#include <pow.h>
#include <primitives/block.h>
#include <primitives/transaction.h>
#include <random.h>
#include <reverse_iterator.h>
#include <script/script.h>
#include <script/sigcache.h>
#include <shutdown.h>
#include <signet.h>
#include <tinyformat.h>
#include <txdb.h>
#include <txmempool.h>
#include <uint256.h>
#include <undo.h>
#include <util/check.h> // For NDEBUG compile time check
#include <util/hasher.h>
#include <util/moneystr.h>
#include <util/rbf.h>
#include <util/strencodings.h>
#include <util/system.h>
#include <util/trace.h>
#include <util/translation.h>
#include <validationinterface.h>
#include <warnings.h>
#include <algorithm>
#include <deque>
#include <numeric>
#include <optional>
#include <string>
using kernel::CCoinsStats;
using kernel::CoinStatsHashType;
using kernel::ComputeUTXOStats;
using node::BLOCKFILE_CHUNK_SIZE;
using node::BlockManager;
using node::BlockMap;
using node::CBlockIndexHeightOnlyComparator;
using node::CBlockIndexWorkComparator;
using node::fImporting;
using node::fPruneMode;
using node::fReindex;
using node::nPruneTarget;
using node::OpenBlockFile;
using node::ReadBlockFromDisk;
using node::SnapshotMetadata;
using node::UNDOFILE_CHUNK_SIZE;
using node::UndoReadFromDisk;
using node::UnlinkPrunedFiles;
#define MICRO 0.000001
#define MILLI 0.001
/** Maximum kilobytes for transactions to store for processing during reorg */
static const unsigned int MAX_DISCONNECTED_TX_POOL_SIZE = 20000;
/** Time to wait between writing blocks/block index to disk. */
static constexpr std::chrono::hours DATABASE_WRITE_INTERVAL{1};
/** Time to wait between flushing chainstate to disk. */
static constexpr std::chrono::hours DATABASE_FLUSH_INTERVAL{24};
/** Maximum age of our tip for us to be considered current for fee estimation */
static constexpr std::chrono::hours MAX_FEE_ESTIMATION_TIP_AGE{3};
const std::vector<std::string> CHECKLEVEL_DOC {
"level 0 reads the blocks from disk",
"level 1 verifies block validity",
"level 2 verifies undo data",
"level 3 checks disconnection of tip blocks",
"level 4 tries to reconnect the blocks",
"each level includes the checks of the previous levels",
};
/** The number of blocks to keep below the deepest prune lock.
* There is nothing special about this number. It is higher than what we
* expect to see in regular mainnet reorgs, but not so high that it would
* noticeably interfere with the pruning mechanism.
* */
static constexpr int PRUNE_LOCK_BUFFER{10};
/**
* Mutex to guard access to validation specific variables, such as reading
* or changing the chainstate.
*
* This may also need to be locked when updating the transaction pool, e.g. on
* AcceptToMemoryPool. See CTxMemPool::cs comment for details.
*
* The transaction pool has a separate lock to allow reading from it and the
* chainstate at the same time.
*/
RecursiveMutex cs_main;
GlobalMutex g_best_block_mutex;
std::condition_variable g_best_block_cv;
uint256 g_best_block;
bool g_parallel_script_checks{false};
bool fRequireStandard = true;
bool fCheckBlockIndex = false;
bool fCheckpointsEnabled = DEFAULT_CHECKPOINTS_ENABLED;
int64_t nMaxTipAge = DEFAULT_MAX_TIP_AGE;
uint256 hashAssumeValid;
arith_uint256 nMinimumChainWork;
const CBlockIndex* CChainState::FindForkInGlobalIndex(const CBlockLocator& locator) const
{
AssertLockHeld(cs_main);
// Find the latest block common to locator and chain - we expect that
// locator.vHave is sorted descending by height.
for (const uint256& hash : locator.vHave) {
const CBlockIndex* pindex{m_blockman.LookupBlockIndex(hash)};
if (pindex) {
if (m_chain.Contains(pindex)) {
return pindex;
}
if (pindex->GetAncestor(m_chain.Height()) == m_chain.Tip()) {
return m_chain.Tip();
}
}
}
return m_chain.Genesis();
}
bool CheckInputScripts(const CTransaction& tx, TxValidationState& state,
const CCoinsViewCache& inputs, unsigned int flags, bool cacheSigStore,
bool cacheFullScriptStore, PrecomputedTransactionData& txdata,
std::vector<CScriptCheck>* pvChecks = nullptr)
EXCLUSIVE_LOCKS_REQUIRED(cs_main);
bool CheckFinalTxAtTip(const CBlockIndex* active_chain_tip, const CTransaction& tx)
{
AssertLockHeld(cs_main);
assert(active_chain_tip); // TODO: Make active_chain_tip a reference
// CheckFinalTxAtTip() uses active_chain_tip.Height()+1 to evaluate
// nLockTime because when IsFinalTx() is called within
// AcceptBlock(), the height of the block *being*
// evaluated is what is used. Thus if we want to know if a
// transaction can be part of the *next* block, we need to call
// IsFinalTx() with one more than active_chain_tip.Height().
const int nBlockHeight = active_chain_tip->nHeight + 1;
// BIP113 requires that time-locked transactions have nLockTime set to
// less than the median time of the previous block they're contained in.
// When the next block is created its previous block will be the current
// chain tip, so we use that to calculate the median time passed to
// IsFinalTx().
const int64_t nBlockTime{active_chain_tip->GetMedianTimePast()};
return IsFinalTx(tx, nBlockHeight, nBlockTime);
}
bool CheckSequenceLocksAtTip(CBlockIndex* tip,
const CCoinsView& coins_view,
const CTransaction& tx,
LockPoints* lp,
bool useExistingLockPoints)
{
assert(tip != nullptr);
CBlockIndex index;
index.pprev = tip;
// CheckSequenceLocksAtTip() uses active_chainstate.m_chain.Height()+1 to evaluate
// height based locks because when SequenceLocks() is called within
// ConnectBlock(), the height of the block *being*
// evaluated is what is used.
// Thus if we want to know if a transaction can be part of the
// *next* block, we need to use one more than active_chainstate.m_chain.Height()
index.nHeight = tip->nHeight + 1;
std::pair<int, int64_t> lockPair;
if (useExistingLockPoints) {
assert(lp);
lockPair.first = lp->height;
lockPair.second = lp->time;
}
else {
std::vector<int> prevheights;
prevheights.resize(tx.vin.size());
for (size_t txinIndex = 0; txinIndex < tx.vin.size(); txinIndex++) {
const CTxIn& txin = tx.vin[txinIndex];
Coin coin;
if (!coins_view.GetCoin(txin.prevout, coin)) {
return error("%s: Missing input", __func__);
}
if (coin.nHeight == MEMPOOL_HEIGHT) {
// Assume all mempool transaction confirm in the next block
prevheights[txinIndex] = tip->nHeight + 1;
} else {
prevheights[txinIndex] = coin.nHeight;
}
}
lockPair = CalculateSequenceLocks(tx, STANDARD_LOCKTIME_VERIFY_FLAGS, prevheights, index);
if (lp) {
lp->height = lockPair.first;
lp->time = lockPair.second;
// Also store the hash of the block with the highest height of
// all the blocks which have sequence locked prevouts.
// This hash needs to still be on the chain
// for these LockPoint calculations to be valid
// Note: It is impossible to correctly calculate a maxInputBlock
// if any of the sequence locked inputs depend on unconfirmed txs,
// except in the special case where the relative lock time/height
// is 0, which is equivalent to no sequence lock. Since we assume
// input height of tip+1 for mempool txs and test the resulting
// lockPair from CalculateSequenceLocks against tip+1. We know
// EvaluateSequenceLocks will fail if there was a non-zero sequence
// lock on a mempool input, so we can use the return value of
// CheckSequenceLocksAtTip to indicate the LockPoints validity
int maxInputHeight = 0;
for (const int height : prevheights) {
// Can ignore mempool inputs since we'll fail if they had non-zero locks
if (height != tip->nHeight+1) {
maxInputHeight = std::max(maxInputHeight, height);
}
}
// tip->GetAncestor(maxInputHeight) should never return a nullptr
// because maxInputHeight is always less than the tip height.
// It would, however, be a bad bug to continue execution, since a
// LockPoints object with the maxInputBlock member set to nullptr
// signifies no relative lock time.
lp->maxInputBlock = Assert(tip->GetAncestor(maxInputHeight));
}
}
return EvaluateSequenceLocks(index, lockPair);
}
// Returns the script flags which should be checked for a given block
static unsigned int GetBlockScriptFlags(const CBlockIndex& block_index, const ChainstateManager& chainman);
static void LimitMempoolSize(CTxMemPool& pool, CCoinsViewCache& coins_cache, std::chrono::seconds age)
EXCLUSIVE_LOCKS_REQUIRED(::cs_main, pool.cs)
{
AssertLockHeld(::cs_main);
AssertLockHeld(pool.cs);
int expired = pool.Expire(GetTime<std::chrono::seconds>() - age);
if (expired != 0) {
LogPrint(BCLog::MEMPOOL, "Expired %i transactions from the memory pool\n", expired);
}
std::vector<COutPoint> vNoSpendsRemaining;
pool.TrimToSize(pool.m_max_size_bytes, &vNoSpendsRemaining);
for (const COutPoint& removed : vNoSpendsRemaining)
coins_cache.Uncache(removed);
}
static bool IsCurrentForFeeEstimation(CChainState& active_chainstate) EXCLUSIVE_LOCKS_REQUIRED(cs_main)
{
AssertLockHeld(cs_main);
if (active_chainstate.IsInitialBlockDownload())
return false;
if (active_chainstate.m_chain.Tip()->GetBlockTime() < count_seconds(GetTime<std::chrono::seconds>() - MAX_FEE_ESTIMATION_TIP_AGE))
return false;
if (active_chainstate.m_chain.Height() < active_chainstate.m_chainman.m_best_header->nHeight - 1) {
return false;
}
return true;
}
void CChainState::MaybeUpdateMempoolForReorg(
DisconnectedBlockTransactions& disconnectpool,
bool fAddToMempool)
{
if (!m_mempool) return;
AssertLockHeld(cs_main);
AssertLockHeld(m_mempool->cs);
std::vector<uint256> vHashUpdate;
// disconnectpool's insertion_order index sorts the entries from
// oldest to newest, but the oldest entry will be the last tx from the
// latest mined block that was disconnected.
// Iterate disconnectpool in reverse, so that we add transactions
// back to the mempool starting with the earliest transaction that had
// been previously seen in a block.
auto it = disconnectpool.queuedTx.get<insertion_order>().rbegin();
while (it != disconnectpool.queuedTx.get<insertion_order>().rend()) {
// ignore validation errors in resurrected transactions
if (!fAddToMempool || (*it)->IsCoinBase() ||
AcceptToMemoryPool(*this, *it, GetTime(),
/*bypass_limits=*/true, /*test_accept=*/false).m_result_type !=
MempoolAcceptResult::ResultType::VALID) {
// If the transaction doesn't make it in to the mempool, remove any
// transactions that depend on it (which would now be orphans).
m_mempool->removeRecursive(**it, MemPoolRemovalReason::REORG);
} else if (m_mempool->exists(GenTxid::Txid((*it)->GetHash()))) {
vHashUpdate.push_back((*it)->GetHash());
}
++it;
}
disconnectpool.queuedTx.clear();
// AcceptToMemoryPool/addUnchecked all assume that new mempool entries have
// no in-mempool children, which is generally not true when adding
// previously-confirmed transactions back to the mempool.
// UpdateTransactionsFromBlock finds descendants of any transactions in
// the disconnectpool that were added back and cleans up the mempool state.
const uint64_t ancestor_count_limit = gArgs.GetIntArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT);
const uint64_t ancestor_size_limit = gArgs.GetIntArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT) * 1000;
m_mempool->UpdateTransactionsFromBlock(vHashUpdate, ancestor_size_limit, ancestor_count_limit);
// Predicate to use for filtering transactions in removeForReorg.
// Checks whether the transaction is still final and, if it spends a coinbase output, mature.
// Also updates valid entries' cached LockPoints if needed.
// If false, the tx is still valid and its lockpoints are updated.
// If true, the tx would be invalid in the next block; remove this entry and all of its descendants.
const auto filter_final_and_mature = [this](CTxMemPool::txiter it)
EXCLUSIVE_LOCKS_REQUIRED(m_mempool->cs, ::cs_main) {
AssertLockHeld(m_mempool->cs);
AssertLockHeld(::cs_main);
const CTransaction& tx = it->GetTx();
// The transaction must be final.
if (!CheckFinalTxAtTip(m_chain.Tip(), tx)) return true;
LockPoints lp = it->GetLockPoints();
const bool validLP{TestLockPointValidity(m_chain, lp)};
CCoinsViewMemPool view_mempool(&CoinsTip(), *m_mempool);
// CheckSequenceLocksAtTip checks if the transaction will be final in the next block to be
// created on top of the new chain. We use useExistingLockPoints=false so that, instead of
// using the information in lp (which might now refer to a block that no longer exists in
// the chain), it will update lp to contain LockPoints relevant to the new chain.
if (!CheckSequenceLocksAtTip(m_chain.Tip(), view_mempool, tx, &lp, validLP)) {
// If CheckSequenceLocksAtTip fails, remove the tx and don't depend on the LockPoints.
return true;
} else if (!validLP) {
// If CheckSequenceLocksAtTip succeeded, it also updated the LockPoints.
// Now update the mempool entry lockpoints as well.
m_mempool->mapTx.modify(it, [&lp](CTxMemPoolEntry& e) { e.UpdateLockPoints(lp); });
}
// If the transaction spends any coinbase outputs, it must be mature.
if (it->GetSpendsCoinbase()) {
for (const CTxIn& txin : tx.vin) {
auto it2 = m_mempool->mapTx.find(txin.prevout.hash);
if (it2 != m_mempool->mapTx.end())
continue;
const Coin& coin{CoinsTip().AccessCoin(txin.prevout)};
assert(!coin.IsSpent());
const auto mempool_spend_height{m_chain.Tip()->nHeight + 1};
if (coin.IsCoinBase() && mempool_spend_height - coin.nHeight < COINBASE_MATURITY) {
return true;
}
}
}
// Transaction is still valid and cached LockPoints are updated.
return false;
};
// We also need to remove any now-immature transactions
m_mempool->removeForReorg(m_chain, filter_final_and_mature);
// Re-limit mempool size, in case we added any transactions
LimitMempoolSize(
*m_mempool,
this->CoinsTip(),
std::chrono::hours{gArgs.GetIntArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY)});
}
/**
* Checks to avoid mempool polluting consensus critical paths since cached
* signature and script validity results will be reused if we validate this
* transaction again during block validation.
* */
static bool CheckInputsFromMempoolAndCache(const CTransaction& tx, TxValidationState& state,
const CCoinsViewCache& view, const CTxMemPool& pool,
unsigned int flags, PrecomputedTransactionData& txdata, CCoinsViewCache& coins_tip)
EXCLUSIVE_LOCKS_REQUIRED(cs_main, pool.cs)
{
AssertLockHeld(cs_main);
AssertLockHeld(pool.cs);
assert(!tx.IsCoinBase());
for (const CTxIn& txin : tx.vin) {
const Coin& coin = view.AccessCoin(txin.prevout);
// This coin was checked in PreChecks and MemPoolAccept
// has been holding cs_main since then.
Assume(!coin.IsSpent());
if (coin.IsSpent()) return false;
// If the Coin is available, there are 2 possibilities:
// it is available in our current ChainstateActive UTXO set,
// or it's a UTXO provided by a transaction in our mempool.
// Ensure the scriptPubKeys in Coins from CoinsView are correct.
const CTransactionRef& txFrom = pool.get(txin.prevout.hash);
if (txFrom) {
assert(txFrom->GetHash() == txin.prevout.hash);
assert(txFrom->vout.size() > txin.prevout.n);
assert(txFrom->vout[txin.prevout.n] == coin.out);
} else {
const Coin& coinFromUTXOSet = coins_tip.AccessCoin(txin.prevout);
assert(!coinFromUTXOSet.IsSpent());
assert(coinFromUTXOSet.out == coin.out);
}
}
// Call CheckInputScripts() to cache signature and script validity against current tip consensus rules.
return CheckInputScripts(tx, state, view, flags, /* cacheSigStore= */ true, /* cacheFullScriptStore= */ true, txdata);
}
namespace {
class MemPoolAccept
{
public:
explicit MemPoolAccept(CTxMemPool& mempool, CChainState& active_chainstate) : m_pool(mempool), m_view(&m_dummy), m_viewmempool(&active_chainstate.CoinsTip(), m_pool), m_active_chainstate(active_chainstate),
m_limit_ancestors(gArgs.GetIntArg("-limitancestorcount", DEFAULT_ANCESTOR_LIMIT)),
m_limit_ancestor_size(gArgs.GetIntArg("-limitancestorsize", DEFAULT_ANCESTOR_SIZE_LIMIT)*1000),
m_limit_descendants(gArgs.GetIntArg("-limitdescendantcount", DEFAULT_DESCENDANT_LIMIT)),
m_limit_descendant_size(gArgs.GetIntArg("-limitdescendantsize", DEFAULT_DESCENDANT_SIZE_LIMIT)*1000) {
}
// We put the arguments we're handed into a struct, so we can pass them
// around easier.
struct ATMPArgs {
const CChainParams& m_chainparams;
const int64_t m_accept_time;
const bool m_bypass_limits;
/*
* Return any outpoints which were not previously present in the coins
* cache, but were added as a result of validating the tx for mempool
* acceptance. This allows the caller to optionally remove the cache
* additions if the associated transaction ends up being rejected by
* the mempool.
*/
std::vector<COutPoint>& m_coins_to_uncache;
const bool m_test_accept;
/** Whether we allow transactions to replace mempool transactions by BIP125 rules. If false,
* any transaction spending the same inputs as a transaction in the mempool is considered
* a conflict. */
const bool m_allow_bip125_replacement;
/** When true, the mempool will not be trimmed when individual transactions are submitted in
* Finalize(). Instead, limits should be enforced at the end to ensure the package is not
* partially submitted.
*/
const bool m_package_submission;
/** When true, use package feerates instead of individual transaction feerates for fee-based
* policies such as mempool min fee and min relay fee.
*/
const bool m_package_feerates;
/** Parameters for single transaction mempool validation. */
static ATMPArgs SingleAccept(const CChainParams& chainparams, int64_t accept_time,
bool bypass_limits, std::vector<COutPoint>& coins_to_uncache,
bool test_accept) {
return ATMPArgs{/* m_chainparams */ chainparams,
/* m_accept_time */ accept_time,
/* m_bypass_limits */ bypass_limits,
/* m_coins_to_uncache */ coins_to_uncache,
/* m_test_accept */ test_accept,
/* m_allow_bip125_replacement */ true,
/* m_package_submission */ false,
/* m_package_feerates */ false,
};
}
/** Parameters for test package mempool validation through testmempoolaccept. */
static ATMPArgs PackageTestAccept(const CChainParams& chainparams, int64_t accept_time,
std::vector<COutPoint>& coins_to_uncache) {
return ATMPArgs{/* m_chainparams */ chainparams,
/* m_accept_time */ accept_time,
/* m_bypass_limits */ false,
/* m_coins_to_uncache */ coins_to_uncache,
/* m_test_accept */ true,
/* m_allow_bip125_replacement */ false,
/* m_package_submission */ false, // not submitting to mempool
/* m_package_feerates */ false,
};
}
/** Parameters for child-with-unconfirmed-parents package validation. */
static ATMPArgs PackageChildWithParents(const CChainParams& chainparams, int64_t accept_time,
std::vector<COutPoint>& coins_to_uncache) {
return ATMPArgs{/* m_chainparams */ chainparams,
/* m_accept_time */ accept_time,
/* m_bypass_limits */ false,
/* m_coins_to_uncache */ coins_to_uncache,
/* m_test_accept */ false,
/* m_allow_bip125_replacement */ false,
/* m_package_submission */ true,
/* m_package_feerates */ true,
};
}
/** Parameters for a single transaction within a package. */
static ATMPArgs SingleInPackageAccept(const ATMPArgs& package_args) {
return ATMPArgs{/* m_chainparams */ package_args.m_chainparams,
/* m_accept_time */ package_args.m_accept_time,
/* m_bypass_limits */ false,
/* m_coins_to_uncache */ package_args.m_coins_to_uncache,
/* m_test_accept */ package_args.m_test_accept,
/* m_allow_bip125_replacement */ true,
/* m_package_submission */ false,
/* m_package_feerates */ false, // only 1 transaction
};
}
private:
// Private ctor to avoid exposing details to clients and allowing the possibility of
// mixing up the order of the arguments. Use static functions above instead.
ATMPArgs(const CChainParams& chainparams,
int64_t accept_time,
bool bypass_limits,
std::vector<COutPoint>& coins_to_uncache,
bool test_accept,
bool allow_bip125_replacement,
bool package_submission,
bool package_feerates)
: m_chainparams{chainparams},
m_accept_time{accept_time},
m_bypass_limits{bypass_limits},
m_coins_to_uncache{coins_to_uncache},
m_test_accept{test_accept},
m_allow_bip125_replacement{allow_bip125_replacement},
m_package_submission{package_submission},
m_package_feerates{package_feerates}
{
}
};
// Single transaction acceptance
MempoolAcceptResult AcceptSingleTransaction(const CTransactionRef& ptx, ATMPArgs& args) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
/**
* Multiple transaction acceptance. Transactions may or may not be interdependent, but must not
* conflict with each other, and the transactions cannot already be in the mempool. Parents must
* come before children if any dependencies exist.
*/
PackageMempoolAcceptResult AcceptMultipleTransactions(const std::vector<CTransactionRef>& txns, ATMPArgs& args) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
/**
* Package (more specific than just multiple transactions) acceptance. Package must be a child
* with all of its unconfirmed parents, and topologically sorted.
*/
PackageMempoolAcceptResult AcceptPackage(const Package& package, ATMPArgs& args) EXCLUSIVE_LOCKS_REQUIRED(cs_main);
private:
// All the intermediate state that gets passed between the various levels
// of checking a given transaction.
struct Workspace {
explicit Workspace(const CTransactionRef& ptx) : m_ptx(ptx), m_hash(ptx->GetHash()) {}
/** Txids of mempool transactions that this transaction directly conflicts with. */
std::set<uint256> m_conflicts;
/** Iterators to mempool entries that this transaction directly conflicts with. */
CTxMemPool::setEntries m_iters_conflicting;
/** Iterators to all mempool entries that would be replaced by this transaction, including
* those it directly conflicts with and their descendants. */
CTxMemPool::setEntries m_all_conflicting;
/** All mempool ancestors of this transaction. */
CTxMemPool::setEntries m_ancestors;
/** Mempool entry constructed for this transaction. Constructed in PreChecks() but not
* inserted into the mempool until Finalize(). */
std::unique_ptr<CTxMemPoolEntry> m_entry;
/** Pointers to the transactions that have been removed from the mempool and replaced by
* this transaction, used to return to the MemPoolAccept caller. Only populated if
* validation is successful and the original transactions are removed. */
std::list<CTransactionRef> m_replaced_transactions;
/** Virtual size of the transaction as used by the mempool, calculated using serialized size
* of the transaction and sigops. */
int64_t m_vsize;
/** Fees paid by this transaction: total input amounts subtracted by total output amounts. */
CAmount m_base_fees;
/** Base fees + any fee delta set by the user with prioritisetransaction. */
CAmount m_modified_fees;
/** Total modified fees of all transactions being replaced. */
CAmount m_conflicting_fees{0};
/** Total virtual size of all transactions being replaced. */
size_t m_conflicting_size{0};
const CTransactionRef& m_ptx;
/** Txid. */
const uint256& m_hash;
TxValidationState m_state;
/** A temporary cache containing serialized transaction data for signature verification.
* Reused across PolicyScriptChecks and ConsensusScriptChecks. */
PrecomputedTransactionData m_precomputed_txdata;
};
// Run the policy checks on a given transaction, excluding any script checks.
// Looks up inputs, calculates feerate, considers replacement, evaluates
// package limits, etc. As this function can be invoked for "free" by a peer,
// only tests that are fast should be done here (to avoid CPU DoS).
bool PreChecks(ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Run checks for mempool replace-by-fee.
bool ReplacementChecks(Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Enforce package mempool ancestor/descendant limits (distinct from individual
// ancestor/descendant limits done in PreChecks).
bool PackageMempoolChecks(const std::vector<CTransactionRef>& txns,
PackageValidationState& package_state) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Run the script checks using our policy flags. As this can be slow, we should
// only invoke this on transactions that have otherwise passed policy checks.
bool PolicyScriptChecks(const ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Re-run the script checks, using consensus flags, and try to cache the
// result in the scriptcache. This should be done after
// PolicyScriptChecks(). This requires that all inputs either be in our
// utxo set or in the mempool.
bool ConsensusScriptChecks(const ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Try to add the transaction to the mempool, removing any conflicts first.
// Returns true if the transaction is in the mempool after any size
// limiting is performed, false otherwise.
bool Finalize(const ATMPArgs& args, Workspace& ws) EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Submit all transactions to the mempool and call ConsensusScriptChecks to add to the script
// cache - should only be called after successful validation of all transactions in the package.
// The package may end up partially-submitted after size limiting; returns true if all
// transactions are successfully added to the mempool, false otherwise.
bool SubmitPackage(const ATMPArgs& args, std::vector<Workspace>& workspaces, PackageValidationState& package_state,
std::map<const uint256, const MempoolAcceptResult>& results)
EXCLUSIVE_LOCKS_REQUIRED(cs_main, m_pool.cs);
// Compare a package's feerate against minimum allowed.
bool CheckFeeRate(size_t package_size, CAmount package_fee, TxValidationState& state) EXCLUSIVE_LOCKS_REQUIRED(::cs_main, m_pool.cs)
{
AssertLockHeld(::cs_main);
AssertLockHeld(m_pool.cs);
CAmount mempoolRejectFee = m_pool.GetMinFee().GetFee(package_size);
if (mempoolRejectFee > 0 && package_fee < mempoolRejectFee) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool min fee not met", strprintf("%d < %d", package_fee, mempoolRejectFee));
}
if (package_fee < ::minRelayTxFee.GetFee(package_size)) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "min relay fee not met", strprintf("%d < %d", package_fee, ::minRelayTxFee.GetFee(package_size)));
}
return true;
}
private:
CTxMemPool& m_pool;
CCoinsViewCache m_view;
CCoinsViewMemPool m_viewmempool;
CCoinsView m_dummy;
CChainState& m_active_chainstate;
// The package limits in effect at the time of invocation.
const size_t m_limit_ancestors;
const size_t m_limit_ancestor_size;
// These may be modified while evaluating a transaction (eg to account for
// in-mempool conflicts; see below).
size_t m_limit_descendants;
size_t m_limit_descendant_size;
/** Whether the transaction(s) would replace any mempool transactions. If so, RBF rules apply. */
bool m_rbf{false};
};
bool MemPoolAccept::PreChecks(ATMPArgs& args, Workspace& ws)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
const CTransactionRef& ptx = ws.m_ptx;
const CTransaction& tx = *ws.m_ptx;
const uint256& hash = ws.m_hash;
// Copy/alias what we need out of args
const int64_t nAcceptTime = args.m_accept_time;
const bool bypass_limits = args.m_bypass_limits;
std::vector<COutPoint>& coins_to_uncache = args.m_coins_to_uncache;
// Alias what we need out of ws
TxValidationState& state = ws.m_state;
std::unique_ptr<CTxMemPoolEntry>& entry = ws.m_entry;
if (!CheckTransaction(tx, state)) {
return false; // state filled in by CheckTransaction
}
// Coinbase is only valid in a block, not as a loose transaction
if (tx.IsCoinBase())
return state.Invalid(TxValidationResult::TX_CONSENSUS, "coinbase");
// Rather not work on nonstandard transactions (unless -testnet/-regtest)
std::string reason;
if (fRequireStandard && !IsStandardTx(tx, reason))
return state.Invalid(TxValidationResult::TX_NOT_STANDARD, reason);
// Do not work on transactions that are too small.
// A transaction with 1 segwit input and 1 P2WPHK output has non-witness size of 82 bytes.
// Transactions smaller than this are not relayed to mitigate CVE-2017-12842 by not relaying
// 64-byte transactions.
if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) < MIN_STANDARD_TX_NONWITNESS_SIZE)
return state.Invalid(TxValidationResult::TX_NOT_STANDARD, "tx-size-small");
// Only accept nLockTime-using transactions that can be mined in the next
// block; we don't want our mempool filled up with transactions that can't
// be mined yet.
if (!CheckFinalTxAtTip(m_active_chainstate.m_chain.Tip(), tx)) {
return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND, "non-final");
}
if (m_pool.exists(GenTxid::Wtxid(tx.GetWitnessHash()))) {
// Exact transaction already exists in the mempool.
return state.Invalid(TxValidationResult::TX_CONFLICT, "txn-already-in-mempool");
} else if (m_pool.exists(GenTxid::Txid(tx.GetHash()))) {
// Transaction with the same non-witness data but different witness (same txid, different
// wtxid) already exists in the mempool.
return state.Invalid(TxValidationResult::TX_CONFLICT, "txn-same-nonwitness-data-in-mempool");
}
// Check for conflicts with in-memory transactions
for (const CTxIn &txin : tx.vin)
{
const CTransaction* ptxConflicting = m_pool.GetConflictTx(txin.prevout);
if (ptxConflicting) {
if (!args.m_allow_bip125_replacement) {
// Transaction conflicts with a mempool tx, but we're not allowing replacements.
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "bip125-replacement-disallowed");
}
if (!ws.m_conflicts.count(ptxConflicting->GetHash()))
{
// Transactions that don't explicitly signal replaceability are
// *not* replaceable with the current logic, even if one of their
// unconfirmed ancestors signals replaceability. This diverges
// from BIP125's inherited signaling description (see CVE-2021-31876).
// Applications relying on first-seen mempool behavior should
// check all unconfirmed ancestors; otherwise an opt-in ancestor
// might be replaced, causing removal of this descendant.
if (!SignalsOptInRBF(*ptxConflicting)) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "txn-mempool-conflict");
}
ws.m_conflicts.insert(ptxConflicting->GetHash());
}
}
}
LockPoints lp;
m_view.SetBackend(m_viewmempool);
const CCoinsViewCache& coins_cache = m_active_chainstate.CoinsTip();
// do all inputs exist?
for (const CTxIn& txin : tx.vin) {
if (!coins_cache.HaveCoinInCache(txin.prevout)) {
coins_to_uncache.push_back(txin.prevout);
}
// Note: this call may add txin.prevout to the coins cache
// (coins_cache.cacheCoins) by way of FetchCoin(). It should be removed
// later (via coins_to_uncache) if this tx turns out to be invalid.
if (!m_view.HaveCoin(txin.prevout)) {
// Are inputs missing because we already have the tx?
for (size_t out = 0; out < tx.vout.size(); out++) {
// Optimistically just do efficient check of cache for outputs
if (coins_cache.HaveCoinInCache(COutPoint(hash, out))) {
return state.Invalid(TxValidationResult::TX_CONFLICT, "txn-already-known");
}
}
// Otherwise assume this might be an orphan tx for which we just haven't seen parents yet
return state.Invalid(TxValidationResult::TX_MISSING_INPUTS, "bad-txns-inputs-missingorspent");
}
}
// This is const, but calls into the back end CoinsViews. The CCoinsViewDB at the bottom of the
// hierarchy brings the best block into scope. See CCoinsViewDB::GetBestBlock().
m_view.GetBestBlock();
// we have all inputs cached now, so switch back to dummy (to protect
// against bugs where we pull more inputs from disk that miss being added
// to coins_to_uncache)
m_view.SetBackend(m_dummy);
assert(m_active_chainstate.m_blockman.LookupBlockIndex(m_view.GetBestBlock()) == m_active_chainstate.m_chain.Tip());
// Only accept BIP68 sequence locked transactions that can be mined in the next
// block; we don't want our mempool filled up with transactions that can't
// be mined yet.
// Pass in m_view which has all of the relevant inputs cached. Note that, since m_view's
// backend was removed, it no longer pulls coins from the mempool.
if (!CheckSequenceLocksAtTip(m_active_chainstate.m_chain.Tip(), m_view, tx, &lp)) {
return state.Invalid(TxValidationResult::TX_PREMATURE_SPEND, "non-BIP68-final");
}
// The mempool holds txs for the next block, so pass height+1 to CheckTxInputs
if (!Consensus::CheckTxInputs(tx, state, m_view, m_active_chainstate.m_chain.Height() + 1, ws.m_base_fees)) {
return false; // state filled in by CheckTxInputs
}
if (fRequireStandard && !AreInputsStandard(tx, m_view)) {
return state.Invalid(TxValidationResult::TX_INPUTS_NOT_STANDARD, "bad-txns-nonstandard-inputs");
}
// Check for non-standard witnesses.
if (tx.HasWitness() && fRequireStandard && !IsWitnessStandard(tx, m_view))
return state.Invalid(TxValidationResult::TX_WITNESS_MUTATED, "bad-witness-nonstandard");
int64_t nSigOpsCost = GetTransactionSigOpCost(tx, m_view, STANDARD_SCRIPT_VERIFY_FLAGS);
// ws.m_modified_fees includes any fee deltas from PrioritiseTransaction
ws.m_modified_fees = ws.m_base_fees;
m_pool.ApplyDelta(hash, ws.m_modified_fees);
// Keep track of transactions that spend a coinbase, which we re-scan
// during reorgs to ensure COINBASE_MATURITY is still met.
bool fSpendsCoinbase = false;
for (const CTxIn &txin : tx.vin) {
const Coin &coin = m_view.AccessCoin(txin.prevout);
if (coin.IsCoinBase()) {
fSpendsCoinbase = true;
break;
}
}
entry.reset(new CTxMemPoolEntry(ptx, ws.m_base_fees, nAcceptTime, m_active_chainstate.m_chain.Height(),
fSpendsCoinbase, nSigOpsCost, lp));
ws.m_vsize = entry->GetTxSize();
if (nSigOpsCost > MAX_STANDARD_TX_SIGOPS_COST)
return state.Invalid(TxValidationResult::TX_NOT_STANDARD, "bad-txns-too-many-sigops",
strprintf("%d", nSigOpsCost));
// No individual transactions are allowed below minRelayTxFee and mempool min fee except from
// disconnected blocks and transactions in a package. Package transactions will be checked using
// package feerate later.
if (!bypass_limits && !args.m_package_feerates && !CheckFeeRate(ws.m_vsize, ws.m_modified_fees, state)) return false;
ws.m_iters_conflicting = m_pool.GetIterSet(ws.m_conflicts);
// Calculate in-mempool ancestors, up to a limit.
if (ws.m_conflicts.size() == 1) {
// In general, when we receive an RBF transaction with mempool conflicts, we want to know whether we
// would meet the chain limits after the conflicts have been removed. However, there isn't a practical
// way to do this short of calculating the ancestor and descendant sets with an overlay cache of
// changed mempool entries. Due to both implementation and runtime complexity concerns, this isn't
// very realistic, thus we only ensure a limited set of transactions are RBF'able despite mempool
// conflicts here. Importantly, we need to ensure that some transactions which were accepted using
// the below carve-out are able to be RBF'ed, without impacting the security the carve-out provides
// for off-chain contract systems (see link in the comment below).
//
// Specifically, the subset of RBF transactions which we allow despite chain limits are those which
// conflict directly with exactly one other transaction (but may evict children of said transaction),
// and which are not adding any new mempool dependencies. Note that the "no new mempool dependencies"
// check is accomplished later, so we don't bother doing anything about it here, but if BIP 125 is
// amended, we may need to move that check to here instead of removing it wholesale.
//
// Such transactions are clearly not merging any existing packages, so we are only concerned with
// ensuring that (a) no package is growing past the package size (not count) limits and (b) we are
// not allowing something to effectively use the (below) carve-out spot when it shouldn't be allowed
// to.
//
// To check these we first check if we meet the RBF criteria, above, and increment the descendant
// limits by the direct conflict and its descendants (as these are recalculated in
// CalculateMempoolAncestors by assuming the new transaction being added is a new descendant, with no
// removals, of each parent's existing dependent set). The ancestor count limits are unmodified (as
// the ancestor limits should be the same for both our new transaction and any conflicts).
// We don't bother incrementing m_limit_descendants by the full removal count as that limit never comes
// into force here (as we're only adding a single transaction).
assert(ws.m_iters_conflicting.size() == 1);
CTxMemPool::txiter conflict = *ws.m_iters_conflicting.begin();
m_limit_descendants += 1;
m_limit_descendant_size += conflict->GetSizeWithDescendants();
}
std::string errString;
if (!m_pool.CalculateMemPoolAncestors(*entry, ws.m_ancestors, m_limit_ancestors, m_limit_ancestor_size, m_limit_descendants, m_limit_descendant_size, errString)) {
ws.m_ancestors.clear();
// If CalculateMemPoolAncestors fails second time, we want the original error string.
std::string dummy_err_string;
// Contracting/payment channels CPFP carve-out:
// If the new transaction is relatively small (up to 40k weight)
// and has at most one ancestor (ie ancestor limit of 2, including
// the new transaction), allow it if its parent has exactly the
// descendant limit descendants.
//
// This allows protocols which rely on distrusting counterparties
// being able to broadcast descendants of an unconfirmed transaction
// to be secure by simply only having two immediately-spendable
// outputs - one for each counterparty. For more info on the uses for
// this, see https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-November/016518.html
if (ws.m_vsize > EXTRA_DESCENDANT_TX_SIZE_LIMIT ||
!m_pool.CalculateMemPoolAncestors(*entry, ws.m_ancestors, 2, m_limit_ancestor_size, m_limit_descendants + 1, m_limit_descendant_size + EXTRA_DESCENDANT_TX_SIZE_LIMIT, dummy_err_string)) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "too-long-mempool-chain", errString);
}
}
// A transaction that spends outputs that would be replaced by it is invalid. Now
// that we have the set of all ancestors we can detect this
// pathological case by making sure ws.m_conflicts and ws.m_ancestors don't
// intersect.
if (const auto err_string{EntriesAndTxidsDisjoint(ws.m_ancestors, ws.m_conflicts, hash)}) {
// We classify this as a consensus error because a transaction depending on something it
// conflicts with would be inconsistent.
return state.Invalid(TxValidationResult::TX_CONSENSUS, "bad-txns-spends-conflicting-tx", *err_string);
}
m_rbf = !ws.m_conflicts.empty();
return true;
}
bool MemPoolAccept::ReplacementChecks(Workspace& ws)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
const CTransaction& tx = *ws.m_ptx;
const uint256& hash = ws.m_hash;
TxValidationState& state = ws.m_state;
CFeeRate newFeeRate(ws.m_modified_fees, ws.m_vsize);
// The replacement transaction must have a higher feerate than its direct conflicts.
// - The motivation for this check is to ensure that the replacement transaction is preferable for
// block-inclusion, compared to what would be removed from the mempool.
// - This logic predates ancestor feerate-based transaction selection, which is why it doesn't
// consider feerates of descendants.
// - Note: Ancestor feerate-based transaction selection has made this comparison insufficient to
// guarantee that this is incentive-compatible for miners, because it is possible for a
// descendant transaction of a direct conflict to pay a higher feerate than the transaction that
// might replace them, under these rules.
if (const auto err_string{PaysMoreThanConflicts(ws.m_iters_conflicting, newFeeRate, hash)}) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "insufficient fee", *err_string);
}
// Calculate all conflicting entries and enforce BIP125 Rule #5.
if (const auto err_string{GetEntriesForConflicts(tx, m_pool, ws.m_iters_conflicting, ws.m_all_conflicting)}) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY,
"too many potential replacements", *err_string);
}
// Enforce BIP125 Rule #2.
if (const auto err_string{HasNoNewUnconfirmed(tx, m_pool, ws.m_iters_conflicting)}) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY,
"replacement-adds-unconfirmed", *err_string);
}
// Check if it's economically rational to mine this transaction rather than the ones it
// replaces and pays for its own relay fees. Enforce BIP125 Rules #3 and #4.
for (CTxMemPool::txiter it : ws.m_all_conflicting) {
ws.m_conflicting_fees += it->GetModifiedFee();
ws.m_conflicting_size += it->GetTxSize();
}
if (const auto err_string{PaysForRBF(ws.m_conflicting_fees, ws.m_modified_fees, ws.m_vsize,
::incrementalRelayFee, hash)}) {
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "insufficient fee", *err_string);
}
return true;
}
bool MemPoolAccept::PackageMempoolChecks(const std::vector<CTransactionRef>& txns,
PackageValidationState& package_state)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
// CheckPackageLimits expects the package transactions to not already be in the mempool.
assert(std::all_of(txns.cbegin(), txns.cend(), [this](const auto& tx)
{ return !m_pool.exists(GenTxid::Txid(tx->GetHash()));}));
std::string err_string;
if (!m_pool.CheckPackageLimits(txns, m_limit_ancestors, m_limit_ancestor_size, m_limit_descendants,
m_limit_descendant_size, err_string)) {
// This is a package-wide error, separate from an individual transaction error.
return package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-mempool-limits", err_string);
}
return true;
}
bool MemPoolAccept::PolicyScriptChecks(const ATMPArgs& args, Workspace& ws)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
const CTransaction& tx = *ws.m_ptx;
TxValidationState& state = ws.m_state;
constexpr unsigned int scriptVerifyFlags = STANDARD_SCRIPT_VERIFY_FLAGS;
// Check input scripts and signatures.
// This is done last to help prevent CPU exhaustion denial-of-service attacks.
if (!CheckInputScripts(tx, state, m_view, scriptVerifyFlags, true, false, ws.m_precomputed_txdata)) {
// SCRIPT_VERIFY_CLEANSTACK requires SCRIPT_VERIFY_WITNESS, so we
// need to turn both off, and compare against just turning off CLEANSTACK
// to see if the failure is specifically due to witness validation.
TxValidationState state_dummy; // Want reported failures to be from first CheckInputScripts
if (!tx.HasWitness() && CheckInputScripts(tx, state_dummy, m_view, scriptVerifyFlags & ~(SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_CLEANSTACK), true, false, ws.m_precomputed_txdata) &&
!CheckInputScripts(tx, state_dummy, m_view, scriptVerifyFlags & ~SCRIPT_VERIFY_CLEANSTACK, true, false, ws.m_precomputed_txdata)) {
// Only the witness is missing, so the transaction itself may be fine.
state.Invalid(TxValidationResult::TX_WITNESS_STRIPPED,
state.GetRejectReason(), state.GetDebugMessage());
}
return false; // state filled in by CheckInputScripts
}
return true;
}
bool MemPoolAccept::ConsensusScriptChecks(const ATMPArgs& args, Workspace& ws)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
const CTransaction& tx = *ws.m_ptx;
const uint256& hash = ws.m_hash;
TxValidationState& state = ws.m_state;
// Check again against the current block tip's script verification
// flags to cache our script execution flags. This is, of course,
// useless if the next block has different script flags from the
// previous one, but because the cache tracks script flags for us it
// will auto-invalidate and we'll just have a few blocks of extra
// misses on soft-fork activation.
//
// This is also useful in case of bugs in the standard flags that cause
// transactions to pass as valid when they're actually invalid. For
// instance the STRICTENC flag was incorrectly allowing certain
// CHECKSIG NOT scripts to pass, even though they were invalid.
//
// There is a similar check in CreateNewBlock() to prevent creating
// invalid blocks (using TestBlockValidity), however allowing such
// transactions into the mempool can be exploited as a DoS attack.
unsigned int currentBlockScriptVerifyFlags{GetBlockScriptFlags(*m_active_chainstate.m_chain.Tip(), m_active_chainstate.m_chainman)};
if (!CheckInputsFromMempoolAndCache(tx, state, m_view, m_pool, currentBlockScriptVerifyFlags,
ws.m_precomputed_txdata, m_active_chainstate.CoinsTip())) {
LogPrintf("BUG! PLEASE REPORT THIS! CheckInputScripts failed against latest-block but not STANDARD flags %s, %s\n", hash.ToString(), state.ToString());
return Assume(false);
}
return true;
}
bool MemPoolAccept::Finalize(const ATMPArgs& args, Workspace& ws)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
const CTransaction& tx = *ws.m_ptx;
const uint256& hash = ws.m_hash;
TxValidationState& state = ws.m_state;
const bool bypass_limits = args.m_bypass_limits;
std::unique_ptr<CTxMemPoolEntry>& entry = ws.m_entry;
// Remove conflicting transactions from the mempool
for (CTxMemPool::txiter it : ws.m_all_conflicting)
{
LogPrint(BCLog::MEMPOOL, "replacing tx %s with %s for %s additional fees, %d delta bytes\n",
it->GetTx().GetHash().ToString(),
hash.ToString(),
FormatMoney(ws.m_modified_fees - ws.m_conflicting_fees),
(int)entry->GetTxSize() - (int)ws.m_conflicting_size);
ws.m_replaced_transactions.push_back(it->GetSharedTx());
}
m_pool.RemoveStaged(ws.m_all_conflicting, false, MemPoolRemovalReason::REPLACED);
// This transaction should only count for fee estimation if:
// - it's not being re-added during a reorg which bypasses typical mempool fee limits
// - the node is not behind
// - the transaction is not dependent on any other transactions in the mempool
// - it's not part of a package. Since package relay is not currently supported, this
// transaction has not necessarily been accepted to miners' mempools.
bool validForFeeEstimation = !bypass_limits && !args.m_package_submission && IsCurrentForFeeEstimation(m_active_chainstate) && m_pool.HasNoInputsOf(tx);
// Store transaction in memory
m_pool.addUnchecked(*entry, ws.m_ancestors, validForFeeEstimation);
// trim mempool and check if tx was trimmed
// If we are validating a package, don't trim here because we could evict a previous transaction
// in the package. LimitMempoolSize() should be called at the very end to make sure the mempool
// is still within limits and package submission happens atomically.
if (!args.m_package_submission && !bypass_limits) {
LimitMempoolSize(m_pool, m_active_chainstate.CoinsTip(), std::chrono::hours{gArgs.GetIntArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY)});
if (!m_pool.exists(GenTxid::Txid(hash)))
return state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool full");
}
return true;
}
bool MemPoolAccept::SubmitPackage(const ATMPArgs& args, std::vector<Workspace>& workspaces,
PackageValidationState& package_state,
std::map<const uint256, const MempoolAcceptResult>& results)
{
AssertLockHeld(cs_main);
AssertLockHeld(m_pool.cs);
// Sanity check: none of the transactions should be in the mempool, and none of the transactions
// should have a same-txid-different-witness equivalent in the mempool.
assert(std::all_of(workspaces.cbegin(), workspaces.cend(), [this](const auto& ws){
return !m_pool.exists(GenTxid::Txid(ws.m_ptx->GetHash())); }));
bool all_submitted = true;
// ConsensusScriptChecks adds to the script cache and is therefore consensus-critical;
// CheckInputsFromMempoolAndCache asserts that transactions only spend coins available from the
// mempool or UTXO set. Submit each transaction to the mempool immediately after calling
// ConsensusScriptChecks to make the outputs available for subsequent transactions.
for (Workspace& ws : workspaces) {
if (!ConsensusScriptChecks(args, ws)) {
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
// Since PolicyScriptChecks() passed, this should never fail.
Assume(false);
all_submitted = false;
package_state.Invalid(PackageValidationResult::PCKG_MEMPOOL_ERROR,
strprintf("BUG! PolicyScriptChecks succeeded but ConsensusScriptChecks failed: %s",
ws.m_ptx->GetHash().ToString()));
}
// Re-calculate mempool ancestors to call addUnchecked(). They may have changed since the
// last calculation done in PreChecks, since package ancestors have already been submitted.
std::string unused_err_string;
if(!m_pool.CalculateMemPoolAncestors(*ws.m_entry, ws.m_ancestors, m_limit_ancestors,
m_limit_ancestor_size, m_limit_descendants,
m_limit_descendant_size, unused_err_string)) {
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
// Since PreChecks() and PackageMempoolChecks() both enforce limits, this should never fail.
Assume(false);
all_submitted = false;
package_state.Invalid(PackageValidationResult::PCKG_MEMPOOL_ERROR,
strprintf("BUG! Mempool ancestors or descendants were underestimated: %s",
ws.m_ptx->GetHash().ToString()));
}
// If we call LimitMempoolSize() for each individual Finalize(), the mempool will not take
// the transaction's descendant feerate into account because it hasn't seen them yet. Also,
// we risk evicting a transaction that a subsequent package transaction depends on. Instead,
// allow the mempool to temporarily bypass limits, the maximum package size) while
// submitting transactions individually and then trim at the very end.
if (!Finalize(args, ws)) {
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
// Since LimitMempoolSize() won't be called, this should never fail.
Assume(false);
all_submitted = false;
package_state.Invalid(PackageValidationResult::PCKG_MEMPOOL_ERROR,
strprintf("BUG! Adding to mempool failed: %s", ws.m_ptx->GetHash().ToString()));
}
}
// It may or may not be the case that all the transactions made it into the mempool. Regardless,
// make sure we haven't exceeded max mempool size.
LimitMempoolSize(m_pool, m_active_chainstate.CoinsTip(),
std::chrono::hours{gArgs.GetIntArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY)});
// Find the wtxids of the transactions that made it into the mempool. Allow partial submission,
// but don't report success unless they all made it into the mempool.
for (Workspace& ws : workspaces) {
if (m_pool.exists(GenTxid::Wtxid(ws.m_ptx->GetWitnessHash()))) {
results.emplace(ws.m_ptx->GetWitnessHash(),
MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions), ws.m_vsize, ws.m_base_fees));
GetMainSignals().TransactionAddedToMempool(ws.m_ptx, m_pool.GetAndIncrementSequence());
} else {
all_submitted = false;
ws.m_state.Invalid(TxValidationResult::TX_MEMPOOL_POLICY, "mempool full");
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
}
}
return all_submitted;
}
MempoolAcceptResult MemPoolAccept::AcceptSingleTransaction(const CTransactionRef& ptx, ATMPArgs& args)
{
AssertLockHeld(cs_main);
LOCK(m_pool.cs); // mempool "read lock" (held through GetMainSignals().TransactionAddedToMempool())
Workspace ws(ptx);
if (!PreChecks(args, ws)) return MempoolAcceptResult::Failure(ws.m_state);
if (m_rbf && !ReplacementChecks(ws)) return MempoolAcceptResult::Failure(ws.m_state);
// Perform the inexpensive checks first and avoid hashing and signature verification unless
// those checks pass, to mitigate CPU exhaustion denial-of-service attacks.
if (!PolicyScriptChecks(args, ws)) return MempoolAcceptResult::Failure(ws.m_state);
if (!ConsensusScriptChecks(args, ws)) return MempoolAcceptResult::Failure(ws.m_state);
// Tx was accepted, but not added
if (args.m_test_accept) {
return MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions), ws.m_vsize, ws.m_base_fees);
}
if (!Finalize(args, ws)) return MempoolAcceptResult::Failure(ws.m_state);
GetMainSignals().TransactionAddedToMempool(ptx, m_pool.GetAndIncrementSequence());
return MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions), ws.m_vsize, ws.m_base_fees);
}
PackageMempoolAcceptResult MemPoolAccept::AcceptMultipleTransactions(const std::vector<CTransactionRef>& txns, ATMPArgs& args)
{
AssertLockHeld(cs_main);
// These context-free package limits can be done before taking the mempool lock.
PackageValidationState package_state;
if (!CheckPackage(txns, package_state)) return PackageMempoolAcceptResult(package_state, {});
std::vector<Workspace> workspaces{};
workspaces.reserve(txns.size());
std::transform(txns.cbegin(), txns.cend(), std::back_inserter(workspaces),
[](const auto& tx) { return Workspace(tx); });
std::map<const uint256, const MempoolAcceptResult> results;
LOCK(m_pool.cs);
// Do all PreChecks first and fail fast to avoid running expensive script checks when unnecessary.
for (Workspace& ws : workspaces) {
if (!PreChecks(args, ws)) {
package_state.Invalid(PackageValidationResult::PCKG_TX, "transaction failed");
// Exit early to avoid doing pointless work. Update the failed tx result; the rest are unfinished.
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
return PackageMempoolAcceptResult(package_state, std::move(results));
}
// Make the coins created by this transaction available for subsequent transactions in the
// package to spend. Since we already checked conflicts in the package and we don't allow
// replacements, we don't need to track the coins spent. Note that this logic will need to be
// updated if package replace-by-fee is allowed in the future.
assert(!args.m_allow_bip125_replacement);
m_viewmempool.PackageAddTransaction(ws.m_ptx);
}
// Transactions must meet two minimum feerates: the mempool minimum fee and min relay fee.
// For transactions consisting of exactly one child and its parents, it suffices to use the
// package feerate (total modified fees / total virtual size) to check this requirement.
const auto m_total_vsize = std::accumulate(workspaces.cbegin(), workspaces.cend(), int64_t{0},
[](int64_t sum, auto& ws) { return sum + ws.m_vsize; });
const auto m_total_modified_fees = std::accumulate(workspaces.cbegin(), workspaces.cend(), CAmount{0},
[](CAmount sum, auto& ws) { return sum + ws.m_modified_fees; });
const CFeeRate package_feerate(m_total_modified_fees, m_total_vsize);
TxValidationState placeholder_state;
if (args.m_package_feerates &&
!CheckFeeRate(m_total_vsize, m_total_modified_fees, placeholder_state)) {
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-fee-too-low");
return PackageMempoolAcceptResult(package_state, package_feerate, {});
}
// Apply package mempool ancestor/descendant limits. Skip if there is only one transaction,
// because it's unnecessary. Also, CPFP carve out can increase the limit for individual
// transactions, but this exemption is not extended to packages in CheckPackageLimits().
std::string err_string;
if (txns.size() > 1 && !PackageMempoolChecks(txns, package_state)) {
return PackageMempoolAcceptResult(package_state, package_feerate, std::move(results));
}
for (Workspace& ws : workspaces) {
if (!PolicyScriptChecks(args, ws)) {
// Exit early to avoid doing pointless work. Update the failed tx result; the rest are unfinished.
package_state.Invalid(PackageValidationResult::PCKG_TX, "transaction failed");
results.emplace(ws.m_ptx->GetWitnessHash(), MempoolAcceptResult::Failure(ws.m_state));
return PackageMempoolAcceptResult(package_state, package_feerate, std::move(results));
}
if (args.m_test_accept) {
// When test_accept=true, transactions that pass PolicyScriptChecks are valid because there are
// no further mempool checks (passing PolicyScriptChecks implies passing ConsensusScriptChecks).
results.emplace(ws.m_ptx->GetWitnessHash(),
MempoolAcceptResult::Success(std::move(ws.m_replaced_transactions),
ws.m_vsize, ws.m_base_fees));
}
}
if (args.m_test_accept) return PackageMempoolAcceptResult(package_state, package_feerate, std::move(results));
if (!SubmitPackage(args, workspaces, package_state, results)) {
// PackageValidationState filled in by SubmitPackage().
return PackageMempoolAcceptResult(package_state, package_feerate, std::move(results));
}
return PackageMempoolAcceptResult(package_state, package_feerate, std::move(results));
}
PackageMempoolAcceptResult MemPoolAccept::AcceptPackage(const Package& package, ATMPArgs& args)
{
AssertLockHeld(cs_main);
PackageValidationState package_state;
// Check that the package is well-formed. If it isn't, we won't try to validate any of the
// transactions and thus won't return any MempoolAcceptResults, just a package-wide error.
// Context-free package checks.
if (!CheckPackage(package, package_state)) return PackageMempoolAcceptResult(package_state, {});
// All transactions in the package must be a parent of the last transaction. This is just an
// opportunity for us to fail fast on a context-free check without taking the mempool lock.
if (!IsChildWithParents(package)) {
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-not-child-with-parents");
return PackageMempoolAcceptResult(package_state, {});
}
// IsChildWithParents() guarantees the package is > 1 transactions.
assert(package.size() > 1);
// The package must be 1 child with all of its unconfirmed parents. The package is expected to
// be sorted, so the last transaction is the child.
const auto& child = package.back();
std::unordered_set<uint256, SaltedTxidHasher> unconfirmed_parent_txids;
std::transform(package.cbegin(), package.cend() - 1,
std::inserter(unconfirmed_parent_txids, unconfirmed_parent_txids.end()),
[](const auto& tx) { return tx->GetHash(); });
// All child inputs must refer to a preceding package transaction or a confirmed UTXO. The only
// way to verify this is to look up the child's inputs in our current coins view (not including
// mempool), and enforce that all parents not present in the package be available at chain tip.
// Since this check can bring new coins into the coins cache, keep track of these coins and
// uncache them if we don't end up submitting this package to the mempool.
const CCoinsViewCache& coins_tip_cache = m_active_chainstate.CoinsTip();
for (const auto& input : child->vin) {
if (!coins_tip_cache.HaveCoinInCache(input.prevout)) {
args.m_coins_to_uncache.push_back(input.prevout);
}
}
// Using the MemPoolAccept m_view cache allows us to look up these same coins faster later.
// This should be connecting directly to CoinsTip, not to m_viewmempool, because we specifically
// require inputs to be confirmed if they aren't in the package.
m_view.SetBackend(m_active_chainstate.CoinsTip());
const auto package_or_confirmed = [this, &unconfirmed_parent_txids](const auto& input) {
return unconfirmed_parent_txids.count(input.prevout.hash) > 0 || m_view.HaveCoin(input.prevout);
};
if (!std::all_of(child->vin.cbegin(), child->vin.cend(), package_or_confirmed)) {
package_state.Invalid(PackageValidationResult::PCKG_POLICY, "package-not-child-with-unconfirmed-parents");
return PackageMempoolAcceptResult(package_state, {});
}
// Protect against bugs where we pull more inputs from disk that miss being added to
// coins_to_uncache. The backend will be connected again when needed in PreChecks.
m_view.SetBackend(m_dummy);
LOCK(m_pool.cs);
std::map<const uint256, const MempoolAcceptResult> results;
// Node operators are free to set their mempool policies however they please, nodes may receive
// transactions in different orders, and malicious counterparties may try to take advantage of
// policy differences to pin or delay propagation of transactions. As such, it's possible for
// some package transaction(s) to already be in the mempool, and we don't want to reject the
// entire package in that case (as that could be a censorship vector). De-duplicate the
// transactions that are already in the mempool, and only call AcceptMultipleTransactions() with
// the new transactions. This ensures we don't double-count transaction counts and sizes when
// checking ancestor/descendant limits, or double-count transaction fees for fee-related policy.
ATMPArgs single_args = ATMPArgs::SingleInPackageAccept(args);
bool quit_early{false};
std::vector<CTransactionRef> txns_new;
for (const auto& tx : package) {
const auto& wtxid = tx->GetWitnessHash();
const auto& txid = tx->GetHash();
// There are 3 possibilities: already in mempool, same-txid-diff-wtxid already in mempool,
// or not in mempool. An already confirmed tx is treated as one not in mempool, because all
// we know is that the inputs aren't available.
if (m_pool.exists(GenTxid::Wtxid(wtxid))) {
// Exact transaction already exists in the mempool.
auto iter = m_pool.GetIter(txid);
assert(iter != std::nullopt);
results.emplace(wtxid, MempoolAcceptResult::MempoolTx(iter.value()->GetTxSize(), iter.value()->GetFee()));
} else if (m_pool.exists(GenTxid::Txid(txid))) {
// Transaction with the same non-witness data but different witness (same txid,
// different wtxid) already exists in the mempool.
//
// We don't allow replacement transactions right now, so just swap the package
// transaction for the mempool one. Note that we are ignoring the validity of the
// package transaction passed in.
// TODO: allow witness replacement in packages.
auto iter = m_pool.GetIter(txid);
assert(iter != std::nullopt);
// Provide the wtxid of the mempool tx so that the caller can look it up in the mempool.
results.emplace(wtxid, MempoolAcceptResult::MempoolTxDifferentWitness(iter.value()->GetTx().GetWitnessHash()));
} else {
// Transaction does not already exist in the mempool.
// Try submitting the transaction on its own.
const auto single_res = AcceptSingleTransaction(tx, single_args);
if (single_res.m_result_type == MempoolAcceptResult::ResultType::VALID) {
// The transaction succeeded on its own and is now in the mempool. Don't include it
// in package validation, because its fees should only be "used" once.
assert(m_pool.exists(GenTxid::Wtxid(wtxid)));
results.emplace(wtxid, single_res);
} else if (single_res.m_state.GetResult() != TxValidationResult::TX_MEMPOOL_POLICY &&
single_res.m_state.GetResult() != TxValidationResult::TX_MISSING_INPUTS) {
// Package validation policy only differs from individual policy in its evaluation
// of feerate. For example, if a transaction fails here due to violation of a
// consensus rule, the result will not change when it is submitted as part of a
// package. To minimize the amount of repeated work, unless the transaction fails
// due to feerate or missing inputs (its parent is a previous transaction in the
// package that failed due to feerate), don't run package validation. Note that this
// decision might not make sense if different types of packages are allowed in the
// future. Continue individually validating the rest of the transactions, because
// some of them may still be valid.
quit_early = true;
} else {
txns_new.push_back(tx);
}
}
}
// Nothing to do if the entire package has already been submitted.
if (quit_early || txns_new.empty()) {
// No package feerate when no package validation was done.
return PackageMempoolAcceptResult(package_state, std::move(results));
}
// Validate the (deduplicated) transactions as a package.
auto submission_result = AcceptMultipleTransactions(txns_new, args);
// Include already-in-mempool transaction results in the final result.
for (const auto& [wtxid, mempoolaccept_res] : results) {
submission_result.m_tx_results.emplace(wtxid, mempoolaccept_res);
}
if (submission_result.m_state.IsValid()) assert(submission_result.m_package_feerate.has_value());
return submission_result;
}
} // anon namespace
MempoolAcceptResult AcceptToMemoryPool(CChainState& active_chainstate, const CTransactionRef& tx,
int64_t accept_time, bool bypass_limits, bool test_accept)
EXCLUSIVE_LOCKS_REQUIRED(::cs_main)
{
AssertLockHeld(::cs_main);
const CChainParams& chainparams{active_chainstate.m_params};
assert(active_chainstate.GetMempool() != nullptr);
CTxMemPool& pool{*active_chainstate.GetMempool()};
std::vector<COutPoint> coins_to_uncache;
auto args = MemPoolAccept::ATMPArgs::SingleAccept(chainparams, accept_time, bypass_limits, coins_to_uncache, test_accept);
const MempoolAcceptResult result = MemPoolAccept(pool, active_chainstate).AcceptSingleTransaction(tx, args);
if (result.m_result_type != MempoolAcceptResult::ResultType::VALID) {
// Remove coins that were not present in the coins cache before calling
// AcceptSingleTransaction(); this is to prevent memory DoS in case we receive a large
// number of invalid transactions that attempt to overrun the in-memory coins cache
// (`CCoinsViewCache::cacheCoins`).
for (const COutPoint& hashTx : coins_to_uncache)
active_chainstate.CoinsTip().Uncache(hashTx);
}
// After we've (potentially) uncached entries, ensure our coins cache is still within its size limits
BlockValidationState state_dummy;
active_chainstate.FlushStateToDisk(state_dummy, FlushStateMode::PERIODIC);
return result;
}
PackageMempoolAcceptResult ProcessNewPackage(CChainState& active_chainstate, CTxMemPool& pool,
const Package& package, bool test_accept)
{
AssertLockHeld(cs_main);
assert(!package.empty());
assert(std::all_of(package.cbegin(), package.cend(), [](const auto& tx){return tx != nullptr;}));
std::vector<COutPoint> coins_to_uncache;
const CChainParams& chainparams = active_chainstate.m_params;
const auto result = [&]() EXCLUSIVE_LOCKS_REQUIRED(cs_main) {
AssertLockHeld(cs_main);
if (test_accept) {
auto args = MemPoolAccept::ATMPArgs::PackageTestAccept(chainparams, GetTime(), coins_to_uncache);
return MemPoolAccept(pool, active_chainstate).AcceptMultipleTransactions(package, args);
} else {
auto args = MemPoolAccept::ATMPArgs::PackageChildWithParents(chainparams, GetTime(), coins_to_uncache);
return MemPoolAccept(pool, active_chainstate).AcceptPackage(package, args);
}
}();
// Uncache coins pertaining to transactions that were not submitted to the mempool.
if (test_accept || result.m_state.IsInvalid()) {
for (const COutPoint& hashTx : coins_to_uncache) {
active_chainstate.CoinsTip().Uncache(hashTx);
}
}
// Ensure the coins cache is still within limits.
BlockValidationState state_dummy;
active_chainstate.FlushStateToDisk(state_dummy, FlushStateMode::PERIODIC);
return result;
}
CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams)
{
int halvings = nHeight / consensusParams.nSubsidyHalvingInterval;
// Force block reward to zero when right shift is undefined.
if (halvings >= 64)
return 0;
CAmount nSubsidy = 50 * COIN;
// Subsidy is cut in half every 210,000 blocks which will occur approximately every 4 years.
nSubsidy >>= halvings;
return nSubsidy;
}
CoinsViews::CoinsViews(
fs::path ldb_name,
size_t cache_size_bytes,
bool in_memory,
bool should_wipe) : m_dbview(
gArgs.GetDataDirNet() / ldb_name, cache_size_bytes, in_memory, should_wipe),
m_catcherview(&m_dbview) {}
void CoinsViews::InitCache()
{
AssertLockHeld(::cs_main);
m_cacheview = std::make_unique<CCoinsViewCache>(&m_catcherview);
}
CChainState::CChainState(
CTxMemPool* mempool,
BlockManager& blockman,
ChainstateManager& chainman,
std::optional<uint256> from_snapshot_blockhash)
: m_mempool(mempool),
m_blockman(blockman),
m_params(chainman.GetParams()),
m_chainman(chainman),
m_from_snapshot_blockhash(from_snapshot_blockhash) {}
void CChainState::InitCoinsDB(
size_t cache_size_bytes,
bool in_memory,
bool should_wipe,
fs::path leveldb_name)
{
if (m_from_snapshot_blockhash) {
leveldb_name += "_" + m_from_snapshot_blockhash->ToString();
}
m_coins_views = std::make_unique<CoinsViews>(
leveldb_name, cache_size_bytes, in_memory, should_wipe);
}
void CChainState::InitCoinsCache(size_t cache_size_bytes)
{
AssertLockHeld(::cs_main);
assert(m_coins_views != nullptr);
m_coinstip_cache_size_bytes = cache_size_bytes;
m_coins_views->InitCache();
}
// Note that though this is marked const, we may end up modifying `m_cached_finished_ibd`, which
// is a performance-related implementation detail. This function must be marked
// `const` so that `CValidationInterface` clients (which are given a `const CChainState*`)
// can call it.
//
bool CChainState::IsInitialBlockDownload() const
{
// Optimization: pre-test latch before taking the lock.
if (m_cached_finished_ibd.load(std::memory_order_relaxed))
return false;
LOCK(cs_main);
if (m_cached_finished_ibd.load(std::memory_order_relaxed))
return false;
if (fImporting || fReindex)
return true;
if (m_chain.Tip() == nullptr)
return true;
if (m_chain.Tip()->nChainWork < nMinimumChainWork)
return true;
if (m_chain.Tip()->GetBlockTime() < (GetTime() - nMaxTipAge))
return true;
LogPrintf("Leaving InitialBlockDownload (latching to false)\n");
m_cached_finished_ibd.store(true, std::memory_order_relaxed);
return false;
}
static void AlertNotify(const std::string& strMessage)
{
uiInterface.NotifyAlertChanged();
#if HAVE_SYSTEM
std::string strCmd = gArgs.GetArg("-alertnotify", "");
if (strCmd.empty()) return;
// Alert text should be plain ascii coming from a trusted source, but to
// be safe we first strip anything not in safeChars, then add single quotes around
// the whole string before passing it to the shell:
std::string singleQuote("'");
std::string safeStatus = SanitizeString(strMessage);
safeStatus = singleQuote+safeStatus+singleQuote;
ReplaceAll(strCmd, "%s", safeStatus);
std::thread t(runCommand, strCmd);
t.detach(); // thread runs free
#endif
}
void CChainState::CheckForkWarningConditions()
{
AssertLockHeld(cs_main);
// Before we get past initial download, we cannot reliably alert about forks
// (we assume we don't get stuck on a fork before finishing our initial sync)
if (IsInitialBlockDownload()) {
return;
}
if (m_chainman.m_best_invalid && m_chainman.m_best_invalid->nChainWork > m_chain.Tip()->nChainWork + (GetBlockProof(*m_chain.Tip()) * 6)) {
LogPrintf("%s: Warning: Found invalid chain at least ~6 blocks longer than our best chain.\nChain state database corruption likely.\n", __func__);
SetfLargeWorkInvalidChainFound(true);
} else {
SetfLargeWorkInvalidChainFound(false);
}
}
// Called both upon regular invalid block discovery *and* InvalidateBlock
void CChainState::InvalidChainFound(CBlockIndex* pindexNew)
{
AssertLockHeld(cs_main);
if (!m_chainman.m_best_invalid || pindexNew->nChainWork > m_chainman.m_best_invalid->nChainWork) {
m_chainman.m_best_invalid = pindexNew;
}
if (m_chainman.m_best_header != nullptr && m_chainman.m_best_header->GetAncestor(pindexNew->nHeight) == pindexNew) {
m_chainman.m_best_header = m_chain.Tip();
}
LogPrintf("%s: invalid block=%s height=%d log2_work=%f date=%s\n", __func__,
pindexNew->GetBlockHash().ToString(), pindexNew->nHeight,
log(pindexNew->nChainWork.getdouble())/log(2.0), FormatISO8601DateTime(pindexNew->GetBlockTime()));
CBlockIndex *tip = m_chain.Tip();
assert (tip);
LogPrintf("%s: current best=%s height=%d log2_work=%f date=%s\n", __func__,
tip->GetBlockHash().ToString(), m_chain.Height(), log(tip->nChainWork.getdouble())/log(2.0),
FormatISO8601DateTime(tip->GetBlockTime()));
CheckForkWarningConditions();
}
// Same as InvalidChainFound, above, except not called directly from InvalidateBlock,
// which does its own setBlockIndexCandidates management.
void CChainState::InvalidBlockFound(CBlockIndex* pindex, const BlockValidationState& state)
{
AssertLockHeld(cs_main);
if (state.GetResult() != BlockValidationResult::BLOCK_MUTATED) {
pindex->nStatus |= BLOCK_FAILED_VALID;
m_chainman.m_failed_blocks.insert(pindex);
m_blockman.m_dirty_blockindex.insert(pindex);
setBlockIndexCandidates.erase(pindex);
InvalidChainFound(pindex);
}
}
void UpdateCoins(const CTransaction& tx, CCoinsViewCache& inputs, CTxUndo &txundo, int nHeight)
{
// mark inputs spent
if (!tx.IsCoinBase()) {
txundo.vprevout.reserve(tx.vin.size());
for (const CTxIn &txin : tx.vin) {
txundo.vprevout.emplace_back();
bool is_spent = inputs.SpendCoin(txin.prevout, &txundo.vprevout.back());
assert(is_spent);
}
}
// add outputs
AddCoins(inputs, tx, nHeight);
}
bool CScriptCheck::operator()() {
const CScript &scriptSig = ptxTo->vin[nIn].scriptSig;
const CScriptWitness *witness = &ptxTo->vin[nIn].scriptWitness;
return VerifyScript(scriptSig, m_tx_out.scriptPubKey, witness, nFlags, CachingTransactionSignatureChecker(ptxTo, nIn, m_tx_out.nValue, cacheStore, *txdata), &error);
}
static CuckooCache::cache<uint256, SignatureCacheHasher> g_scriptExecutionCache;
static CSHA256 g_scriptExecutionCacheHasher;
void InitScriptExecutionCache() {
// Setup the salted hasher
uint256 nonce = GetRandHash();
// We want the nonce to be 64 bytes long to force the hasher to process
// this chunk, which makes later hash computations more efficient. We
// just write our 32-byte entropy twice to fill the 64 bytes.
g_scriptExecutionCacheHasher.Write(nonce.begin(), 32);
g_scriptExecutionCacheHasher.Write(nonce.begin(), 32);
// nMaxCacheSize is unsigned. If -maxsigcachesize is set to zero,
// setup_bytes creates the minimum possible cache (2 elements).
size_t nMaxCacheSize = std::min(std::max((int64_t)0, gArgs.GetIntArg("-maxsigcachesize", DEFAULT_MAX_SIG_CACHE_SIZE) / 2), MAX_MAX_SIG_CACHE_SIZE) * ((size_t) 1 << 20);
size_t nElems = g_scriptExecutionCache.setup_bytes(nMaxCacheSize);
LogPrintf("Using %zu MiB out of %zu/2 requested for script execution cache, able to store %zu elements\n",
(nElems*sizeof(uint256)) >>20, (nMaxCacheSize*2)>>20, nElems);
}
/**
* Check whether all of this transaction's input scripts succeed.
*
* This involves ECDSA signature checks so can be computationally intensive. This function should
* only be called after the cheap sanity checks in CheckTxInputs passed.
*
* If pvChecks is not nullptr, script checks are pushed onto it instead of being performed inline. Any
* script checks which are not necessary (eg due to script execution cache hits) are, obviously,
* not pushed onto pvChecks/run.
*
* Setting cacheSigStore/cacheFullScriptStore to false will remove elements from the corresponding cache
* which are matched. This is useful for checking blocks where we will likely never need the cache
* entry again.
*
* Note that we may set state.reason to NOT_STANDARD for extra soft-fork flags in flags, block-checking
* callers should probably reset it to CONSENSUS in such cases.
*
* Non-static (and re-declared) in src/test/txvalidationcache_tests.cpp
*/
bool CheckInputScripts(const CTransaction& tx, TxValidationState& state,
const CCoinsViewCache& inputs, unsigned int flags, bool cacheSigStore,
bool cacheFullScriptStore, PrecomputedTransactionData& txdata,
std::vector<CScriptCheck>* pvChecks)
{
if (tx.IsCoinBase()) return true;
if (pvChecks) {
pvChecks->reserve(tx.vin.size());
}
// First check if script executions have been cached with the same
// flags. Note that this assumes that the inputs provided are
// correct (ie that the transaction hash which is in tx's prevouts
// properly commits to the scriptPubKey in the inputs view of that
// transaction).
uint256 hashCacheEntry;
CSHA256 hasher = g_scriptExecutionCacheHasher;
hasher.Write(tx.GetWitnessHash().begin(), 32).Write((unsigned char*)&flags, sizeof(flags)).Finalize(hashCacheEntry.begin());
AssertLockHeld(cs_main); //TODO: Remove this requirement by making CuckooCache not require external locks
if (g_scriptExecutionCache.contains(hashCacheEntry, !cacheFullScriptStore)) {
return true;
}
if (!txdata.m_spent_outputs_ready) {
std::vector<CTxOut> spent_outputs;
spent_outputs.reserve(tx.vin.size());
for (const auto& txin : tx.vin) {
const COutPoint& prevout = txin.prevout;
const Coin& coin = inputs.AccessCoin(prevout);
assert(!coin.IsSpent());
spent_outputs.emplace_back(coin.out);
}
txdata.Init(tx, std::move(spent_outputs));
}
assert(txdata.m_spent_outputs.size() == tx.vin.size());
for (unsigned int i = 0; i < tx.vin.size(); i++) {
// We very carefully only pass in things to CScriptCheck which
// are clearly committed to by tx' witness hash. This provides
// a sanity check that our caching is not introducing consensus
// failures through additional data in, eg, the coins being
// spent being checked as a part of CScriptCheck.
// Verify signature
CScriptCheck check(txdata.m_spent_outputs[i], tx, i, flags, cacheSigStore, &txdata);
if (pvChecks) {
pvChecks->push_back(CScriptCheck());
check.swap(pvChecks->back());
} else if (!check()) {
if (flags & STANDARD_NOT_MANDATORY_VERIFY_FLAGS) {
// Check whether the failure was caused by a
// non-mandatory script verification check, such as
// non-standard DER encodings or non-null dummy
// arguments; if so, ensure we return NOT_STANDARD
// instead of CONSENSUS to avoid downstream users
// splitting the network between upgraded and
// non-upgraded nodes by banning CONSENSUS-failing
// data providers.
CScriptCheck check2(txdata.m_spent_outputs[i], tx, i,
flags & ~STANDARD_NOT_MANDATORY_VERIFY_FLAGS, cacheSigStore, &txdata);
if (check2())
return state.Invalid(TxValidationResult::TX_NOT_STANDARD, strprintf("non-mandatory-script-verify-flag (%s)", ScriptErrorString(check.GetScriptError())));
}
// MANDATORY flag failures correspond to
// TxValidationResult::TX_CONSENSUS. Because CONSENSUS
// failures are the most serious case of validation
// failures, we may need to consider using
// RECENT_CONSENSUS_CHANGE for any script failure that
// could be due to non-upgraded nodes which we may want to
// support, to avoid splitting the network (but this
// depends on the details of how net_processing handles
// such errors).
return state.Invalid(TxValidationResult::TX_CONSENSUS, strprintf("mandatory-script-verify-flag-failed (%s)", ScriptErrorString(check.GetScriptError())));
}
}
if (cacheFullScriptStore && !pvChecks) {
// We executed all of the provided scripts, and were told to
// cache the result. Do so now.
g_scriptExecutionCache.insert(hashCacheEntry);
}
return true;
}
bool AbortNode(BlockValidationState& state, const std::string& strMessage, const bilingual_str& userMessage)
{
AbortNode(strMessage, userMessage);
return state.Error(strMessage);
}
/**
* Restore the UTXO in a Coin at a given COutPoint
* @param undo The Coin to be restored.
* @param view The coins view to which to apply the changes.
* @param out The out point that corresponds to the tx input.
* @return A DisconnectResult as an int
*/
int ApplyTxInUndo(Coin&& undo, CCoinsViewCache& view, const COutPoint& out)
{
bool fClean = true;
if (view.HaveCoin(out)) fClean = false; // overwriting transaction output
if (undo.nHeight == 0) {
// Missing undo metadata (height and coinbase). Older versions included this
// information only in undo records for the last spend of a transactions'
// outputs. This implies that it must be present for some other output of the same tx.
const Coin& alternate = AccessByTxid(view, out.hash);
if (!alternate.IsSpent()) {
undo.nHeight = alternate.nHeight;
undo.fCoinBase = alternate.fCoinBase;
} else {
return DISCONNECT_FAILED; // adding output for transaction without known metadata
}
}
// If the coin already exists as an unspent coin in the cache, then the
// possible_overwrite parameter to AddCoin must be set to true. We have
// already checked whether an unspent coin exists above using HaveCoin, so
// we don't need to guess. When fClean is false, an unspent coin already
// existed and it is an overwrite.
view.AddCoin(out, std::move(undo), !fClean);
return fClean ? DISCONNECT_OK : DISCONNECT_UNCLEAN;
}
/** Undo the effects of this block (with given index) on the UTXO set represented by coins.
* When FAILED is returned, view is left in an indeterminate state. */
DisconnectResult CChainState::DisconnectBlock(const CBlock& block, const CBlockIndex* pindex, CCoinsViewCache& view)
{
AssertLockHeld(::cs_main);
bool fClean = true;
CBlockUndo blockUndo;
if (!UndoReadFromDisk(blockUndo, pindex)) {
error("DisconnectBlock(): failure reading undo data");
return DISCONNECT_FAILED;
}
if (blockUndo.vtxundo.size() + 1 != block.vtx.size()) {
error("DisconnectBlock(): block and undo data inconsistent");
return DISCONNECT_FAILED;
}
// undo transactions in reverse order
for (int i = block.vtx.size() - 1; i >= 0; i--) {
const CTransaction &tx = *(block.vtx[i]);
uint256 hash = tx.GetHash();
bool is_coinbase = tx.IsCoinBase();
// Check that all outputs are available and match the outputs in the block itself
// exactly.
for (size_t o = 0; o < tx.vout.size(); o++) {
if (!tx.vout[o].scriptPubKey.IsUnspendable()) {
COutPoint out(hash, o);
Coin coin;
bool is_spent = view.SpendCoin(out, &coin);
if (!is_spent || tx.vout[o] != coin.out || pindex->nHeight != coin.nHeight || is_coinbase != coin.fCoinBase) {
fClean = false; // transaction output mismatch
}
}
}
// restore inputs
if (i > 0) { // not coinbases
CTxUndo &txundo = blockUndo.vtxundo[i-1];
if (txundo.vprevout.size() != tx.vin.size()) {
error("DisconnectBlock(): transaction and undo data inconsistent");
return DISCONNECT_FAILED;
}
for (unsigned int j = tx.vin.size(); j > 0;) {
--j;
const COutPoint& out = tx.vin[j].prevout;
int res = ApplyTxInUndo(std::move(txundo.vprevout[j]), view, out);
if (res == DISCONNECT_FAILED) return DISCONNECT_FAILED;
fClean = fClean && res != DISCONNECT_UNCLEAN;
}
// At this point, all of txundo.vprevout should have been moved out.
}
}
// move best block pointer to prevout block
view.SetBestBlock(pindex->pprev->GetBlockHash());
return fClean ? DISCONNECT_OK : DISCONNECT_UNCLEAN;
}
static CCheckQueue<CScriptCheck> scriptcheckqueue(128);
void StartScriptCheckWorkerThreads(int threads_num)
{
scriptcheckqueue.StartWorkerThreads(threads_num);
}
void StopScriptCheckWorkerThreads()
{
scriptcheckqueue.StopWorkerThreads();
}
/**
* Threshold condition checker that triggers when unknown versionbits are seen on the network.
*/
class WarningBitsConditionChecker : public AbstractThresholdConditionChecker
{
private:
const ChainstateManager& m_chainman;
int m_bit;
public:
explicit WarningBitsConditionChecker(const ChainstateManager& chainman, int bit) : m_chainman{chainman}, m_bit(bit) {}
int64_t BeginTime(const Consensus::Params& params) const override { return 0; }
int64_t EndTime(const Consensus::Params& params) const override { return std::numeric_limits<int64_t>::max(); }
int Period(const Consensus::Params& params) const override { return params.nMinerConfirmationWindow; }
int Threshold(const Consensus::Params& params) const override { return params.nRuleChangeActivationThreshold; }
bool Condition(const CBlockIndex* pindex, const Consensus::Params& params) const override
{
return pindex->nHeight >= params.MinBIP9WarningHeight &&
((pindex->nVersion & VERSIONBITS_TOP_MASK) == VERSIONBITS_TOP_BITS) &&
((pindex->nVersion >> m_bit) & 1) != 0 &&
((m_chainman.m_versionbitscache.ComputeBlockVersion(pindex->pprev, params) >> m_bit) & 1) == 0;
}
};
static std::array<ThresholdConditionCache, VERSIONBITS_NUM_BITS> warningcache GUARDED_BY(cs_main);
static unsigned int GetBlockScriptFlags(const CBlockIndex& block_index, const ChainstateManager& chainman)
{
const Consensus::Params& consensusparams = chainman.GetConsensus();
// BIP16 didn't become active until Apr 1 2012 (on mainnet, and
// retroactively applied to testnet)
// However, only one historical block violated the P2SH rules (on both
// mainnet and testnet).
// Similarly, only one historical block violated the TAPROOT rules on
// mainnet.
// For simplicity, always leave P2SH+WITNESS+TAPROOT on except for the two
// violating blocks.
uint32_t flags{SCRIPT_VERIFY_P2SH | SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_TAPROOT};
const auto it{consensusparams.script_flag_exceptions.find(*Assert(block_index.phashBlock))};
if (it != consensusparams.script_flag_exceptions.end()) {
flags = it->second;
}
// Enforce the DERSIG (BIP66) rule
if (DeploymentActiveAt(block_index, chainman, Consensus::DEPLOYMENT_DERSIG)) {
flags |= SCRIPT_VERIFY_DERSIG;
}
// Enforce CHECKLOCKTIMEVERIFY (BIP65)
if (DeploymentActiveAt(block_index, chainman, Consensus::DEPLOYMENT_CLTV)) {
flags |= SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY;
}
// Enforce CHECKSEQUENCEVERIFY (BIP112)
if (DeploymentActiveAt(block_index, chainman, Consensus::DEPLOYMENT_CSV)) {
flags |= SCRIPT_VERIFY_CHECKSEQUENCEVERIFY;
}
// Enforce BIP147 NULLDUMMY (activated simultaneously with segwit)
if (DeploymentActiveAt(block_index, chainman, Consensus::DEPLOYMENT_SEGWIT)) {
flags |= SCRIPT_VERIFY_NULLDUMMY;
}
return flags;
}
static int64_t nTimeCheck = 0;
static int64_t nTimeForks = 0;
static int64_t nTimeConnect = 0;
static int64_t nTimeVerify = 0;
static int64_t nTimeUndo = 0;
static int64_t nTimeIndex = 0;
static int64_t nTimeTotal = 0;
static int64_t nBlocksTotal = 0;
/** Apply the effects of this block (with given index) on the UTXO set represented by coins.
* Validity checks that depend on the UTXO set are also done; ConnectBlock()
* can fail if those validity checks fail (among other reasons). */
bool CChainState::ConnectBlock(const CBlock& block, BlockValidationState& state, CBlockIndex* pindex,
CCoinsViewCache& view, bool fJustCheck)
{
AssertLockHeld(cs_main);
assert(pindex);
uint256 block_hash{block.GetHash()};
assert(*pindex->phashBlock == block_hash);
int64_t nTimeStart = GetTimeMicros();
// Check it again in case a previous version let a bad block in
// NOTE: We don't currently (re-)invoke ContextualCheckBlock() or
// ContextualCheckBlockHeader() here. This means that if we add a new
// consensus rule that is enforced in one of those two functions, then we
// may have let in a block that violates the rule prior to updating the
// software, and we would NOT be enforcing the rule here. Fully solving
// upgrade from one software version to the next after a consensus rule
// change is potentially tricky and issue-specific (see NeedsRedownload()
// for one approach that was used for BIP 141 deployment).
// Also, currently the rule against blocks more than 2 hours in the future
// is enforced in ContextualCheckBlockHeader(); we wouldn't want to
// re-enforce that rule here (at least until we make it impossible for
// m_adjusted_time_callback() to go backward).
if (!CheckBlock(block, state, m_params.GetConsensus(), !fJustCheck, !fJustCheck)) {
if (state.GetResult() == BlockValidationResult::BLOCK_MUTATED) {
// We don't write down blocks to disk if they may have been
// corrupted, so this should be impossible unless we're having hardware
// problems.
return AbortNode(state, "Corrupt block found indicating potential hardware failure; shutting down");
}
return error("%s: Consensus::CheckBlock: %s", __func__, state.ToString());
}
// verify that the view's current state corresponds to the previous block
uint256 hashPrevBlock = pindex->pprev == nullptr ? uint256() : pindex->pprev->GetBlockHash();
assert(hashPrevBlock == view.GetBestBlock());
nBlocksTotal++;
// Special case for the genesis block, skipping connection of its transactions
// (its coinbase is unspendable)
if (block_hash == m_params.GetConsensus().hashGenesisBlock) {
if (!fJustCheck)
view.SetBestBlock(pindex->GetBlockHash());
return true;
}
bool fScriptChecks = true;
if (!hashAssumeValid.IsNull()) {
// We've been configured with the hash of a block which has been externally verified to have a valid history.
// A suitable default value is included with the software and updated from time to time. Because validity
// relative to a piece of software is an objective fact these defaults can be easily reviewed.
// This setting doesn't force the selection of any particular chain but makes validating some faster by
// effectively caching the result of part of the verification.
BlockMap::const_iterator it = m_blockman.m_block_index.find(hashAssumeValid);
if (it != m_blockman.m_block_index.end()) {
if (it->second.GetAncestor(pindex->nHeight) == pindex &&
m_chainman.m_best_header->GetAncestor(pindex->nHeight) == pindex &&
m_chainman.m_best_header->nChainWork >= nMinimumChainWork) {
// This block is a member of the assumed verified chain and an ancestor of the best header.
// Script verification is skipped when connecting blocks under the
// assumevalid block. Assuming the assumevalid block is valid this
// is safe because block merkle hashes are still computed and checked,
// Of course, if an assumed valid block is invalid due to false scriptSigs
// this optimization would allow an invalid chain to be accepted.
// The equivalent time check discourages hash power from extorting the network via DOS attack
// into accepting an invalid block through telling users they must manually set assumevalid.
// Requiring a software change or burying the invalid block, regardless of the setting, makes
// it hard to hide the implication of the demand. This also avoids having release candidates
// that are hardly doing any signature verification at all in testing without having to
// artificially set the default assumed verified block further back.
// The test against nMinimumChainWork prevents the skipping when denied access to any chain at
// least as good as the expected chain.
fScriptChecks = (GetBlockProofEquivalentTime(*m_chainman.m_best_header, *pindex, *m_chainman.m_best_header, m_params.GetConsensus()) <= 60 * 60 * 24 * 7 * 2);
}
}
}
int64_t nTime1 = GetTimeMicros(); nTimeCheck += nTime1 - nTimeStart;
LogPrint(BCLog::BENCH, " - Sanity checks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime1 - nTimeStart), nTimeCheck * MICRO, nTimeCheck * MILLI / nBlocksTotal);
// Do not allow blocks that contain transactions which 'overwrite' older transactions,
// unless those are already completely spent.
// If such overwrites are allowed, coinbases and transactions depending upon those
// can be duplicated to remove the ability to spend the first instance -- even after
// being sent to another address.
// See BIP30, CVE-2012-1909, and http://r6.ca/blog/20120206T005236Z.html for more information.
// This rule was originally applied to all blocks with a timestamp after March 15, 2012, 0:00 UTC.
// Now that the whole chain is irreversibly beyond that time it is applied to all blocks except the
// two in the chain that violate it. This prevents exploiting the issue against nodes during their
// initial block download.
bool fEnforceBIP30 = !((pindex->nHeight==91842 && pindex->GetBlockHash() == uint256S("0x00000000000a4d0a398161ffc163c503763b1f4360639393e0e4c8e300e0caec")) ||
(pindex->nHeight==91880 && pindex->GetBlockHash() == uint256S("0x00000000000743f190a18c5577a3c2d2a1f610ae9601ac046a38084ccb7cd721")));
// Once BIP34 activated it was not possible to create new duplicate coinbases and thus other than starting
// with the 2 existing duplicate coinbase pairs, not possible to create overwriting txs. But by the
// time BIP34 activated, in each of the existing pairs the duplicate coinbase had overwritten the first
// before the first had been spent. Since those coinbases are sufficiently buried it's no longer possible to create further
// duplicate transactions descending from the known pairs either.
// If we're on the known chain at height greater than where BIP34 activated, we can save the db accesses needed for the BIP30 check.
// BIP34 requires that a block at height X (block X) has its coinbase
// scriptSig start with a CScriptNum of X (indicated height X). The above
// logic of no longer requiring BIP30 once BIP34 activates is flawed in the
// case that there is a block X before the BIP34 height of 227,931 which has
// an indicated height Y where Y is greater than X. The coinbase for block
// X would also be a valid coinbase for block Y, which could be a BIP30
// violation. An exhaustive search of all mainnet coinbases before the
// BIP34 height which have an indicated height greater than the block height
// reveals many occurrences. The 3 lowest indicated heights found are
// 209,921, 490,897, and 1,983,702 and thus coinbases for blocks at these 3
// heights would be the first opportunity for BIP30 to be violated.
// The search reveals a great many blocks which have an indicated height
// greater than 1,983,702, so we simply remove the optimization to skip
// BIP30 checking for blocks at height 1,983,702 or higher. Before we reach
// that block in another 25 years or so, we should take advantage of a
// future consensus change to do a new and improved version of BIP34 that
// will actually prevent ever creating any duplicate coinbases in the
// future.
static constexpr int BIP34_IMPLIES_BIP30_LIMIT = 1983702;
// There is no potential to create a duplicate coinbase at block 209,921
// because this is still before the BIP34 height and so explicit BIP30
// checking is still active.
// The final case is block 176,684 which has an indicated height of
// 490,897. Unfortunately, this issue was not discovered until about 2 weeks
// before block 490,897 so there was not much opportunity to address this
// case other than to carefully analyze it and determine it would not be a
// problem. Block 490,897 was, in fact, mined with a different coinbase than
// block 176,684, but it is important to note that even if it hadn't been or
// is remined on an alternate fork with a duplicate coinbase, we would still
// not run into a BIP30 violation. This is because the coinbase for 176,684
// is spent in block 185,956 in transaction
// d4f7fbbf92f4a3014a230b2dc70b8058d02eb36ac06b4a0736d9d60eaa9e8781. This
// spending transaction can't be duplicated because it also spends coinbase
// 0328dd85c331237f18e781d692c92de57649529bd5edf1d01036daea32ffde29. This
// coinbase has an indicated height of over 4.2 billion, and wouldn't be
// duplicatable until that height, and it's currently impossible to create a
// chain that long. Nevertheless we may wish to consider a future soft fork
// which retroactively prevents block 490,897 from creating a duplicate
// coinbase. The two historical BIP30 violations often provide a confusing
// edge case when manipulating the UTXO and it would be simpler not to have
// another edge case to deal with.
// testnet3 has no blocks before the BIP34 height with indicated heights
// post BIP34 before approximately height 486,000,000. After block
// 1,983,702 testnet3 starts doing unnecessary BIP30 checking again.
assert(pindex->pprev);
CBlockIndex* pindexBIP34height = pindex->pprev->GetAncestor(m_params.GetConsensus().BIP34Height);
//Only continue to enforce if we're below BIP34 activation height or the block hash at that height doesn't correspond.
fEnforceBIP30 = fEnforceBIP30 && (!pindexBIP34height || !(pindexBIP34height->GetBlockHash() == m_params.GetConsensus().BIP34Hash));
// TODO: Remove BIP30 checking from block height 1,983,702 on, once we have a
// consensus change that ensures coinbases at those heights cannot
// duplicate earlier coinbases.
if (fEnforceBIP30 || pindex->nHeight >= BIP34_IMPLIES_BIP30_LIMIT) {
for (const auto& tx : block.vtx) {
for (size_t o = 0; o < tx->vout.size(); o++) {
if (view.HaveCoin(COutPoint(tx->GetHash(), o))) {
LogPrintf("ERROR: ConnectBlock(): tried to overwrite transaction\n");
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-txns-BIP30");
}
}
}
}
// Enforce BIP68 (sequence locks)
int nLockTimeFlags = 0;
if (DeploymentActiveAt(*pindex, m_chainman, Consensus::DEPLOYMENT_CSV)) {
nLockTimeFlags |= LOCKTIME_VERIFY_SEQUENCE;
}
// Get the script flags for this block
unsigned int flags{GetBlockScriptFlags(*pindex, m_chainman)};
int64_t nTime2 = GetTimeMicros(); nTimeForks += nTime2 - nTime1;
LogPrint(BCLog::BENCH, " - Fork checks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime2 - nTime1), nTimeForks * MICRO, nTimeForks * MILLI / nBlocksTotal);
CBlockUndo blockundo;
// Precomputed transaction data pointers must not be invalidated
// until after `control` has run the script checks (potentially
// in multiple threads). Preallocate the vector size so a new allocation
// doesn't invalidate pointers into the vector, and keep txsdata in scope
// for as long as `control`.
CCheckQueueControl<CScriptCheck> control(fScriptChecks && g_parallel_script_checks ? &scriptcheckqueue : nullptr);
std::vector<PrecomputedTransactionData> txsdata(block.vtx.size());
std::vector<int> prevheights;
CAmount nFees = 0;
int nInputs = 0;
int64_t nSigOpsCost = 0;
blockundo.vtxundo.reserve(block.vtx.size() - 1);
for (unsigned int i = 0; i < block.vtx.size(); i++)
{
const CTransaction &tx = *(block.vtx[i]);
nInputs += tx.vin.size();
if (!tx.IsCoinBase())
{
CAmount txfee = 0;
TxValidationState tx_state;
if (!Consensus::CheckTxInputs(tx, tx_state, view, pindex->nHeight, txfee)) {
// Any transaction validation failure in ConnectBlock is a block consensus failure
state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
tx_state.GetRejectReason(), tx_state.GetDebugMessage());
return error("%s: Consensus::CheckTxInputs: %s, %s", __func__, tx.GetHash().ToString(), state.ToString());
}
nFees += txfee;
if (!MoneyRange(nFees)) {
LogPrintf("ERROR: %s: accumulated fee in the block out of range.\n", __func__);
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-txns-accumulated-fee-outofrange");
}
// Check that transaction is BIP68 final
// BIP68 lock checks (as opposed to nLockTime checks) must
// be in ConnectBlock because they require the UTXO set
prevheights.resize(tx.vin.size());
for (size_t j = 0; j < tx.vin.size(); j++) {
prevheights[j] = view.AccessCoin(tx.vin[j].prevout).nHeight;
}
if (!SequenceLocks(tx, nLockTimeFlags, prevheights, *pindex)) {
LogPrintf("ERROR: %s: contains a non-BIP68-final transaction\n", __func__);
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-txns-nonfinal");
}
}
// GetTransactionSigOpCost counts 3 types of sigops:
// * legacy (always)
// * p2sh (when P2SH enabled in flags and excludes coinbase)
// * witness (when witness enabled in flags and excludes coinbase)
nSigOpsCost += GetTransactionSigOpCost(tx, view, flags);
if (nSigOpsCost > MAX_BLOCK_SIGOPS_COST) {
LogPrintf("ERROR: ConnectBlock(): too many sigops\n");
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-blk-sigops");
}
if (!tx.IsCoinBase())
{
std::vector<CScriptCheck> vChecks;
bool fCacheResults = fJustCheck; /* Don't cache results if we're actually connecting blocks (still consult the cache, though) */
TxValidationState tx_state;
if (fScriptChecks && !CheckInputScripts(tx, tx_state, view, flags, fCacheResults, fCacheResults, txsdata[i], g_parallel_script_checks ? &vChecks : nullptr)) {
// Any transaction validation failure in ConnectBlock is a block consensus failure
state.Invalid(BlockValidationResult::BLOCK_CONSENSUS,
tx_state.GetRejectReason(), tx_state.GetDebugMessage());
return error("ConnectBlock(): CheckInputScripts on %s failed with %s",
tx.GetHash().ToString(), state.ToString());
}
control.Add(vChecks);
}
CTxUndo undoDummy;
if (i > 0) {
blockundo.vtxundo.push_back(CTxUndo());
}
UpdateCoins(tx, view, i == 0 ? undoDummy : blockundo.vtxundo.back(), pindex->nHeight);
}
int64_t nTime3 = GetTimeMicros(); nTimeConnect += nTime3 - nTime2;
LogPrint(BCLog::BENCH, " - Connect %u transactions: %.2fms (%.3fms/tx, %.3fms/txin) [%.2fs (%.2fms/blk)]\n", (unsigned)block.vtx.size(), MILLI * (nTime3 - nTime2), MILLI * (nTime3 - nTime2) / block.vtx.size(), nInputs <= 1 ? 0 : MILLI * (nTime3 - nTime2) / (nInputs-1), nTimeConnect * MICRO, nTimeConnect * MILLI / nBlocksTotal);
CAmount blockReward = nFees + GetBlockSubsidy(pindex->nHeight, m_params.GetConsensus());
if (block.vtx[0]->GetValueOut() > blockReward) {
LogPrintf("ERROR: ConnectBlock(): coinbase pays too much (actual=%d vs limit=%d)\n", block.vtx[0]->GetValueOut(), blockReward);
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-amount");
}
if (!control.Wait()) {
LogPrintf("ERROR: %s: CheckQueue failed\n", __func__);
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "block-validation-failed");
}
int64_t nTime4 = GetTimeMicros(); nTimeVerify += nTime4 - nTime2;
LogPrint(BCLog::BENCH, " - Verify %u txins: %.2fms (%.3fms/txin) [%.2fs (%.2fms/blk)]\n", nInputs - 1, MILLI * (nTime4 - nTime2), nInputs <= 1 ? 0 : MILLI * (nTime4 - nTime2) / (nInputs-1), nTimeVerify * MICRO, nTimeVerify * MILLI / nBlocksTotal);
if (fJustCheck)
return true;
if (!m_blockman.WriteUndoDataForBlock(blockundo, state, pindex, m_params)) {
return false;
}
int64_t nTime5 = GetTimeMicros(); nTimeUndo += nTime5 - nTime4;
LogPrint(BCLog::BENCH, " - Write undo data: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime5 - nTime4), nTimeUndo * MICRO, nTimeUndo * MILLI / nBlocksTotal);
if (!pindex->IsValid(BLOCK_VALID_SCRIPTS)) {
pindex->RaiseValidity(BLOCK_VALID_SCRIPTS);
m_blockman.m_dirty_blockindex.insert(pindex);
}
assert(pindex->phashBlock);
// add this block to the view's block chain
view.SetBestBlock(pindex->GetBlockHash());
int64_t nTime6 = GetTimeMicros(); nTimeIndex += nTime6 - nTime5;
LogPrint(BCLog::BENCH, " - Index writing: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime6 - nTime5), nTimeIndex * MICRO, nTimeIndex * MILLI / nBlocksTotal);
TRACE6(validation, block_connected,
block_hash.data(),
pindex->nHeight,
block.vtx.size(),
nInputs,
nSigOpsCost,
nTime5 - nTimeStart // in microseconds (µs)
);
return true;
}
CoinsCacheSizeState CChainState::GetCoinsCacheSizeState()
{
AssertLockHeld(::cs_main);
return this->GetCoinsCacheSizeState(
m_coinstip_cache_size_bytes,
m_mempool ? m_mempool->m_max_size_bytes : 0);
}
CoinsCacheSizeState CChainState::GetCoinsCacheSizeState(
size_t max_coins_cache_size_bytes,
size_t max_mempool_size_bytes)
{
AssertLockHeld(::cs_main);
const int64_t nMempoolUsage = m_mempool ? m_mempool->DynamicMemoryUsage() : 0;
int64_t cacheSize = CoinsTip().DynamicMemoryUsage();
int64_t nTotalSpace =
max_coins_cache_size_bytes + std::max<int64_t>(int64_t(max_mempool_size_bytes) - nMempoolUsage, 0);
//! No need to periodic flush if at least this much space still available.
static constexpr int64_t MAX_BLOCK_COINSDB_USAGE_BYTES = 10 * 1024 * 1024; // 10MB
int64_t large_threshold =
std::max((9 * nTotalSpace) / 10, nTotalSpace - MAX_BLOCK_COINSDB_USAGE_BYTES);
if (cacheSize > nTotalSpace) {
LogPrintf("Cache size (%s) exceeds total space (%s)\n", cacheSize, nTotalSpace);
return CoinsCacheSizeState::CRITICAL;
} else if (cacheSize > large_threshold) {
return CoinsCacheSizeState::LARGE;
}
return CoinsCacheSizeState::OK;
}
bool CChainState::FlushStateToDisk(
BlockValidationState &state,
FlushStateMode mode,
int nManualPruneHeight)
{
LOCK(cs_main);
assert(this->CanFlushToDisk());
static std::chrono::microseconds nLastWrite{0};
static std::chrono::microseconds nLastFlush{0};
std::set<int> setFilesToPrune;
bool full_flush_completed = false;
const size_t coins_count = CoinsTip().GetCacheSize();
const size_t coins_mem_usage = CoinsTip().DynamicMemoryUsage();
try {
{
bool fFlushForPrune = false;
bool fDoFullFlush = false;
CoinsCacheSizeState cache_state = GetCoinsCacheSizeState();
LOCK(m_blockman.cs_LastBlockFile);
if (fPruneMode && (m_blockman.m_check_for_pruning || nManualPruneHeight > 0) && !fReindex) {
// make sure we don't prune above any of the prune locks bestblocks
// pruning is height-based
int last_prune{m_chain.Height()}; // last height we can prune
std::optional<std::string> limiting_lock; // prune lock that actually was the limiting factor, only used for logging
for (const auto& prune_lock : m_blockman.m_prune_locks) {
if (prune_lock.second.height_first == std::numeric_limits<int>::max()) continue;
// Remove the buffer and one additional block here to get actual height that is outside of the buffer
const int lock_height{prune_lock.second.height_first - PRUNE_LOCK_BUFFER - 1};
last_prune = std::max(1, std::min(last_prune, lock_height));
if (last_prune == lock_height) {
limiting_lock = prune_lock.first;
}
}
if (limiting_lock) {
LogPrint(BCLog::PRUNE, "%s limited pruning to height %d\n", limiting_lock.value(), last_prune);
}
if (nManualPruneHeight > 0) {
LOG_TIME_MILLIS_WITH_CATEGORY("find files to prune (manual)", BCLog::BENCH);
m_blockman.FindFilesToPruneManual(setFilesToPrune, std::min(last_prune, nManualPruneHeight), m_chain.Height());
} else {
LOG_TIME_MILLIS_WITH_CATEGORY("find files to prune", BCLog::BENCH);
m_blockman.FindFilesToPrune(setFilesToPrune, m_params.PruneAfterHeight(), m_chain.Height(), last_prune, IsInitialBlockDownload());
m_blockman.m_check_for_pruning = false;
}
if (!setFilesToPrune.empty()) {
fFlushForPrune = true;
if (!m_blockman.m_have_pruned) {
m_blockman.m_block_tree_db->WriteFlag("prunedblockfiles", true);
m_blockman.m_have_pruned = true;
}
}
}
const auto nNow = GetTime<std::chrono::microseconds>();
// Avoid writing/flushing immediately after startup.
if (nLastWrite.count() == 0) {
nLastWrite = nNow;
}
if (nLastFlush.count() == 0) {
nLastFlush = nNow;
}
// The cache is large and we're within 10% and 10 MiB of the limit, but we have time now (not in the middle of a block processing).
bool fCacheLarge = mode == FlushStateMode::PERIODIC && cache_state >= CoinsCacheSizeState::LARGE;
// The cache is over the limit, we have to write now.
bool fCacheCritical = mode == FlushStateMode::IF_NEEDED && cache_state >= CoinsCacheSizeState::CRITICAL;
// It's been a while since we wrote the block index to disk. Do this frequently, so we don't need to redownload after a crash.
bool fPeriodicWrite = mode == FlushStateMode::PERIODIC && nNow > nLastWrite + DATABASE_WRITE_INTERVAL;
// It's been very long since we flushed the cache. Do this infrequently, to optimize cache usage.
bool fPeriodicFlush = mode == FlushStateMode::PERIODIC && nNow > nLastFlush + DATABASE_FLUSH_INTERVAL;
// Combine all conditions that result in a full cache flush.
fDoFullFlush = (mode == FlushStateMode::ALWAYS) || fCacheLarge || fCacheCritical || fPeriodicFlush || fFlushForPrune;
// Write blocks and block index to disk.
if (fDoFullFlush || fPeriodicWrite) {
// Ensure we can write block index
if (!CheckDiskSpace(gArgs.GetBlocksDirPath())) {
return AbortNode(state, "Disk space is too low!", _("Disk space is too low!"));
}
{
LOG_TIME_MILLIS_WITH_CATEGORY("write block and undo data to disk", BCLog::BENCH);
// First make sure all block and undo data is flushed to disk.
m_blockman.FlushBlockFile();
}
// Then update all block file information (which may refer to block and undo files).
{
LOG_TIME_MILLIS_WITH_CATEGORY("write block index to disk", BCLog::BENCH);
if (!m_blockman.WriteBlockIndexDB()) {
return AbortNode(state, "Failed to write to block index database");
}
}
// Finally remove any pruned files
if (fFlushForPrune) {
LOG_TIME_MILLIS_WITH_CATEGORY("unlink pruned files", BCLog::BENCH);
UnlinkPrunedFiles(setFilesToPrune);
}
nLastWrite = nNow;
}
// Flush best chain related state. This can only be done if the blocks / block index write was also done.
if (fDoFullFlush && !CoinsTip().GetBestBlock().IsNull()) {
LOG_TIME_MILLIS_WITH_CATEGORY(strprintf("write coins cache to disk (%d coins, %.2fkB)",
coins_count, coins_mem_usage / 1000), BCLog::BENCH);
// Typical Coin structures on disk are around 48 bytes in size.
// Pushing a new one to the database can cause it to be written
// twice (once in the log, and once in the tables). This is already
// an overestimation, as most will delete an existing entry or
// overwrite one. Still, use a conservative safety factor of 2.
if (!CheckDiskSpace(gArgs.GetDataDirNet(), 48 * 2 * 2 * CoinsTip().GetCacheSize())) {
return AbortNode(state, "Disk space is too low!", _("Disk space is too low!"));
}
// Flush the chainstate (which may refer to block index entries).
if (!CoinsTip().Flush())
return AbortNode(state, "Failed to write to coin database");
nLastFlush = nNow;
full_flush_completed = true;
TRACE5(utxocache, flush,
(int64_t)(GetTimeMicros() - nNow.count()), // in microseconds (µs)
(uint32_t)mode,
(uint64_t)coins_count,
(uint64_t)coins_mem_usage,
(bool)fFlushForPrune);
}
}
if (full_flush_completed) {
// Update best block in wallet (so we can detect restored wallets).
GetMainSignals().ChainStateFlushed(m_chain.GetLocator());
}
} catch (const std::runtime_error& e) {
return AbortNode(state, std::string("System error while flushing: ") + e.what());
}
return true;
}
void CChainState::ForceFlushStateToDisk()
{
BlockValidationState state;
if (!this->FlushStateToDisk(state, FlushStateMode::ALWAYS)) {
LogPrintf("%s: failed to flush state (%s)\n", __func__, state.ToString());
}
}
void CChainState::PruneAndFlush()
{
BlockValidationState state;
m_blockman.m_check_for_pruning = true;
if (!this->FlushStateToDisk(state, FlushStateMode::NONE)) {
LogPrintf("%s: failed to flush state (%s)\n", __func__, state.ToString());
}
}
static void DoWarning(const bilingual_str& warning)
{
static bool fWarned = false;
SetMiscWarning(warning);
if (!fWarned) {
AlertNotify(warning.original);
fWarned = true;
}
}
/** Private helper function that concatenates warning messages. */
static void AppendWarning(bilingual_str& res, const bilingual_str& warn)
{
if (!res.empty()) res += Untranslated(", ");
res += warn;
}
static void UpdateTipLog(
const CCoinsViewCache& coins_tip,
const CBlockIndex* tip,
const CChainParams& params,
const std::string& func_name,
const std::string& prefix,
const std::string& warning_messages) EXCLUSIVE_LOCKS_REQUIRED(::cs_main)
{
AssertLockHeld(::cs_main);
LogPrintf("%s%s: new best=%s height=%d version=0x%08x log2_work=%f tx=%lu date='%s' progress=%f cache=%.1fMiB(%utxo)%s\n",
prefix, func_name,
tip->GetBlockHash().ToString(), tip->nHeight, tip->nVersion,
log(tip->nChainWork.getdouble()) / log(2.0), (unsigned long)tip->nChainTx,
FormatISO8601DateTime(tip->GetBlockTime()),
GuessVerificationProgress(params.TxData(), tip),
coins_tip.DynamicMemoryUsage() * (1.0 / (1 << 20)),
coins_tip.GetCacheSize(),
!warning_messages.empty() ? strprintf(" warning='%s'", warning_messages) : "");
}
void CChainState::UpdateTip(const CBlockIndex* pindexNew)
{
AssertLockHeld(::cs_main);
const auto& coins_tip = this->CoinsTip();
// The remainder of the function isn't relevant if we are not acting on
// the active chainstate, so return if need be.
if (this != &m_chainman.ActiveChainstate()) {
// Only log every so often so that we don't bury log messages at the tip.
constexpr int BACKGROUND_LOG_INTERVAL = 2000;
if (pindexNew->nHeight % BACKGROUND_LOG_INTERVAL == 0) {
UpdateTipLog(coins_tip, pindexNew, m_params, __func__, "[background validation] ", "");
}
return;
}
// New best block
if (m_mempool) {
m_mempool->AddTransactionsUpdated(1);
}
{
LOCK(g_best_block_mutex);
g_best_block = pindexNew->GetBlockHash();
g_best_block_cv.notify_all();
}
bilingual_str warning_messages;
if (!this->IsInitialBlockDownload()) {
const CBlockIndex* pindex = pindexNew;
for (int bit = 0; bit < VERSIONBITS_NUM_BITS; bit++) {
WarningBitsConditionChecker checker(m_chainman, bit);
ThresholdState state = checker.GetStateFor(pindex, m_params.GetConsensus(), warningcache.at(bit));
if (state == ThresholdState::ACTIVE || state == ThresholdState::LOCKED_IN) {
const bilingual_str warning = strprintf(_("Unknown new rules activated (versionbit %i)"), bit);
if (state == ThresholdState::ACTIVE) {
DoWarning(warning);
} else {
AppendWarning(warning_messages, warning);
}
}
}
}
UpdateTipLog(coins_tip, pindexNew, m_params, __func__, "", warning_messages.original);
}
/** Disconnect m_chain's tip.
* After calling, the mempool will be in an inconsistent state, with
* transactions from disconnected blocks being added to disconnectpool. You
* should make the mempool consistent again by calling MaybeUpdateMempoolForReorg.
* with cs_main held.
*
* If disconnectpool is nullptr, then no disconnected transactions are added to
* disconnectpool (note that the caller is responsible for mempool consistency
* in any case).
*/
bool CChainState::DisconnectTip(BlockValidationState& state, DisconnectedBlockTransactions* disconnectpool)
{
AssertLockHeld(cs_main);
if (m_mempool) AssertLockHeld(m_mempool->cs);
CBlockIndex *pindexDelete = m_chain.Tip();
assert(pindexDelete);
// Read block from disk.
std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();
CBlock& block = *pblock;
if (!ReadBlockFromDisk(block, pindexDelete, m_params.GetConsensus())) {
return error("DisconnectTip(): Failed to read block");
}
// Apply the block atomically to the chain state.
int64_t nStart = GetTimeMicros();
{
CCoinsViewCache view(&CoinsTip());
assert(view.GetBestBlock() == pindexDelete->GetBlockHash());
if (DisconnectBlock(block, pindexDelete, view) != DISCONNECT_OK)
return error("DisconnectTip(): DisconnectBlock %s failed", pindexDelete->GetBlockHash().ToString());
bool flushed = view.Flush();
assert(flushed);
}
LogPrint(BCLog::BENCH, "- Disconnect block: %.2fms\n", (GetTimeMicros() - nStart) * MILLI);
{
// Prune locks that began at or after the tip should be moved backward so they get a chance to reorg
const int max_height_first{pindexDelete->nHeight - 1};
for (auto& prune_lock : m_blockman.m_prune_locks) {
if (prune_lock.second.height_first <= max_height_first) continue;
prune_lock.second.height_first = max_height_first;
LogPrint(BCLog::PRUNE, "%s prune lock moved back to %d\n", prune_lock.first, max_height_first);
}
}
// Write the chain state to disk, if necessary.
if (!FlushStateToDisk(state, FlushStateMode::IF_NEEDED)) {
return false;
}
if (disconnectpool && m_mempool) {
// Save transactions to re-add to mempool at end of reorg
for (auto it = block.vtx.rbegin(); it != block.vtx.rend(); ++it) {
disconnectpool->addTransaction(*it);
}
while (disconnectpool->DynamicMemoryUsage() > MAX_DISCONNECTED_TX_POOL_SIZE * 1000) {
// Drop the earliest entry, and remove its children from the mempool.
auto it = disconnectpool->queuedTx.get<insertion_order>().begin();
m_mempool->removeRecursive(**it, MemPoolRemovalReason::REORG);
disconnectpool->removeEntry(it);
}
}
m_chain.SetTip(pindexDelete->pprev);
UpdateTip(pindexDelete->pprev);
// Let wallets know transactions went from 1-confirmed to
// 0-confirmed or conflicted:
GetMainSignals().BlockDisconnected(pblock, pindexDelete);
return true;
}
static int64_t nTimeReadFromDiskTotal = 0;
static int64_t nTimeConnectTotal = 0;
static int64_t nTimeFlush = 0;
static int64_t nTimeChainState = 0;
static int64_t nTimePostConnect = 0;
struct PerBlockConnectTrace {
CBlockIndex* pindex = nullptr;
std::shared_ptr<const CBlock> pblock;
PerBlockConnectTrace() = default;
};
/**
* Used to track blocks whose transactions were applied to the UTXO state as a
* part of a single ActivateBestChainStep call.
*
* This class is single-use, once you call GetBlocksConnected() you have to throw
* it away and make a new one.
*/
class ConnectTrace {
private:
std::vector<PerBlockConnectTrace> blocksConnected;
public:
explicit ConnectTrace() : blocksConnected(1) {}
void BlockConnected(CBlockIndex* pindex, std::shared_ptr<const CBlock> pblock) {
assert(!blocksConnected.back().pindex);
assert(pindex);
assert(pblock);
blocksConnected.back().pindex = pindex;
blocksConnected.back().pblock = std::move(pblock);
blocksConnected.emplace_back();
}
std::vector<PerBlockConnectTrace>& GetBlocksConnected() {
// We always keep one extra block at the end of our list because
// blocks are added after all the conflicted transactions have
// been filled in. Thus, the last entry should always be an empty
// one waiting for the transactions from the next block. We pop
// the last entry here to make sure the list we return is sane.
assert(!blocksConnected.back().pindex);
blocksConnected.pop_back();
return blocksConnected;
}
};
/**
* Connect a new block to m_chain. pblock is either nullptr or a pointer to a CBlock
* corresponding to pindexNew, to bypass loading it again from disk.
*
* The block is added to connectTrace if connection succeeds.
*/
bool CChainState::ConnectTip(BlockValidationState& state, CBlockIndex* pindexNew, const std::shared_ptr<const CBlock>& pblock, ConnectTrace& connectTrace, DisconnectedBlockTransactions& disconnectpool)
{
AssertLockHeld(cs_main);
if (m_mempool) AssertLockHeld(m_mempool->cs);
assert(pindexNew->pprev == m_chain.Tip());
// Read block from disk.
int64_t nTime1 = GetTimeMicros();
std::shared_ptr<const CBlock> pthisBlock;
if (!pblock) {
std::shared_ptr<CBlock> pblockNew = std::make_shared<CBlock>();
if (!ReadBlockFromDisk(*pblockNew, pindexNew, m_params.GetConsensus())) {
return AbortNode(state, "Failed to read block");
}
pthisBlock = pblockNew;
} else {
LogPrint(BCLog::BENCH, " - Using cached block\n");
pthisBlock = pblock;
}
const CBlock& blockConnecting = *pthisBlock;
// Apply the block atomically to the chain state.
int64_t nTime2 = GetTimeMicros(); nTimeReadFromDiskTotal += nTime2 - nTime1;
int64_t nTime3;
LogPrint(BCLog::BENCH, " - Load block from disk: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime2 - nTime1) * MILLI, nTimeReadFromDiskTotal * MICRO, nTimeReadFromDiskTotal * MILLI / nBlocksTotal);
{
CCoinsViewCache view(&CoinsTip());
bool rv = ConnectBlock(blockConnecting, state, pindexNew, view);
GetMainSignals().BlockChecked(blockConnecting, state);
if (!rv) {
if (state.IsInvalid())
InvalidBlockFound(pindexNew, state);
return error("%s: ConnectBlock %s failed, %s", __func__, pindexNew->GetBlockHash().ToString(), state.ToString());
}
nTime3 = GetTimeMicros(); nTimeConnectTotal += nTime3 - nTime2;
assert(nBlocksTotal > 0);
LogPrint(BCLog::BENCH, " - Connect total: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime3 - nTime2) * MILLI, nTimeConnectTotal * MICRO, nTimeConnectTotal * MILLI / nBlocksTotal);
bool flushed = view.Flush();
assert(flushed);
}
int64_t nTime4 = GetTimeMicros(); nTimeFlush += nTime4 - nTime3;
LogPrint(BCLog::BENCH, " - Flush: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime4 - nTime3) * MILLI, nTimeFlush * MICRO, nTimeFlush * MILLI / nBlocksTotal);
// Write the chain state to disk, if necessary.
if (!FlushStateToDisk(state, FlushStateMode::IF_NEEDED)) {
return false;
}
int64_t nTime5 = GetTimeMicros(); nTimeChainState += nTime5 - nTime4;
LogPrint(BCLog::BENCH, " - Writing chainstate: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime5 - nTime4) * MILLI, nTimeChainState * MICRO, nTimeChainState * MILLI / nBlocksTotal);
// Remove conflicting transactions from the mempool.;
if (m_mempool) {
m_mempool->removeForBlock(blockConnecting.vtx, pindexNew->nHeight);
disconnectpool.removeForBlock(blockConnecting.vtx);
}
// Update m_chain & related variables.
m_chain.SetTip(pindexNew);
UpdateTip(pindexNew);
int64_t nTime6 = GetTimeMicros(); nTimePostConnect += nTime6 - nTime5; nTimeTotal += nTime6 - nTime1;
LogPrint(BCLog::BENCH, " - Connect postprocess: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime6 - nTime5) * MILLI, nTimePostConnect * MICRO, nTimePostConnect * MILLI / nBlocksTotal);
LogPrint(BCLog::BENCH, "- Connect block: %.2fms [%.2fs (%.2fms/blk)]\n", (nTime6 - nTime1) * MILLI, nTimeTotal * MICRO, nTimeTotal * MILLI / nBlocksTotal);
connectTrace.BlockConnected(pindexNew, std::move(pthisBlock));
return true;
}
/**
* Return the tip of the chain with the most work in it, that isn't
* known to be invalid (it's however far from certain to be valid).
*/
CBlockIndex* CChainState::FindMostWorkChain()
{
AssertLockHeld(::cs_main);
do {
CBlockIndex *pindexNew = nullptr;
// Find the best candidate header.
{
std::set<CBlockIndex*, CBlockIndexWorkComparator>::reverse_iterator it = setBlockIndexCandidates.rbegin();
if (it == setBlockIndexCandidates.rend())
return nullptr;
pindexNew = *it;
}
// Check whether all blocks on the path between the currently active chain and the candidate are valid.
// Just going until the active chain is an optimization, as we know all blocks in it are valid already.
CBlockIndex *pindexTest = pindexNew;
bool fInvalidAncestor = false;
while (pindexTest && !m_chain.Contains(pindexTest)) {
assert(pindexTest->HaveTxsDownloaded() || pindexTest->nHeight == 0);
// Pruned nodes may have entries in setBlockIndexCandidates for
// which block files have been deleted. Remove those as candidates
// for the most work chain if we come across them; we can't switch
// to a chain unless we have all the non-active-chain parent blocks.
bool fFailedChain = pindexTest->nStatus & BLOCK_FAILED_MASK;
bool fMissingData = !(pindexTest->nStatus & BLOCK_HAVE_DATA);
if (fFailedChain || fMissingData) {
// Candidate chain is not usable (either invalid or missing data)
if (fFailedChain && (m_chainman.m_best_invalid == nullptr || pindexNew->nChainWork > m_chainman.m_best_invalid->nChainWork)) {
m_chainman.m_best_invalid = pindexNew;
}
CBlockIndex *pindexFailed = pindexNew;
// Remove the entire chain from the set.
while (pindexTest != pindexFailed) {
if (fFailedChain) {
pindexFailed->nStatus |= BLOCK_FAILED_CHILD;
} else if (fMissingData) {
// If we're missing data, then add back to m_blocks_unlinked,
// so that if the block arrives in the future we can try adding
// to setBlockIndexCandidates again.
m_blockman.m_blocks_unlinked.insert(
std::make_pair(pindexFailed->pprev, pindexFailed));
}
setBlockIndexCandidates.erase(pindexFailed);
pindexFailed = pindexFailed->pprev;
}
setBlockIndexCandidates.erase(pindexTest);
fInvalidAncestor = true;
break;
}
pindexTest = pindexTest->pprev;
}
if (!fInvalidAncestor)
return pindexNew;
} while(true);
}
/** Delete all entries in setBlockIndexCandidates that are worse than the current tip. */
void CChainState::PruneBlockIndexCandidates() {
// Note that we can't delete the current block itself, as we may need to return to it later in case a
// reorganization to a better block fails.
std::set<CBlockIndex*, CBlockIndexWorkComparator>::iterator it = setBlockIndexCandidates.begin();
while (it != setBlockIndexCandidates.end() && setBlockIndexCandidates.value_comp()(*it, m_chain.Tip())) {
setBlockIndexCandidates.erase(it++);
}
// Either the current tip or a successor of it we're working towards is left in setBlockIndexCandidates.
assert(!setBlockIndexCandidates.empty());
}
/**
* Try to make some progress towards making pindexMostWork the active block.
* pblock is either nullptr or a pointer to a CBlock corresponding to pindexMostWork.
*
* @returns true unless a system error occurred
*/
bool CChainState::ActivateBestChainStep(BlockValidationState& state, CBlockIndex* pindexMostWork, const std::shared_ptr<const CBlock>& pblock, bool& fInvalidFound, ConnectTrace& connectTrace)
{
AssertLockHeld(cs_main);
if (m_mempool) AssertLockHeld(m_mempool->cs);
const CBlockIndex* pindexOldTip = m_chain.Tip();
const CBlockIndex* pindexFork = m_chain.FindFork(pindexMostWork);
// Disconnect active blocks which are no longer in the best chain.
bool fBlocksDisconnected = false;
DisconnectedBlockTransactions disconnectpool;
while (m_chain.Tip() && m_chain.Tip() != pindexFork) {
if (!DisconnectTip(state, &disconnectpool)) {
// This is likely a fatal error, but keep the mempool consistent,
// just in case. Only remove from the mempool in this case.
MaybeUpdateMempoolForReorg(disconnectpool, false);
// If we're unable to disconnect a block during normal operation,
// then that is a failure of our local system -- we should abort
// rather than stay on a less work chain.
AbortNode(state, "Failed to disconnect block; see debug.log for details");
return false;
}
fBlocksDisconnected = true;
}
// Build list of new blocks to connect (in descending height order).
std::vector<CBlockIndex*> vpindexToConnect;
bool fContinue = true;
int nHeight = pindexFork ? pindexFork->nHeight : -1;
while (fContinue && nHeight != pindexMostWork->nHeight) {
// Don't iterate the entire list of potential improvements toward the best tip, as we likely only need
// a few blocks along the way.
int nTargetHeight = std::min(nHeight + 32, pindexMostWork->nHeight);
vpindexToConnect.clear();
vpindexToConnect.reserve(nTargetHeight - nHeight);
CBlockIndex* pindexIter = pindexMostWork->GetAncestor(nTargetHeight);
while (pindexIter && pindexIter->nHeight != nHeight) {
vpindexToConnect.push_back(pindexIter);
pindexIter = pindexIter->pprev;
}
nHeight = nTargetHeight;
// Connect new blocks.
for (CBlockIndex* pindexConnect : reverse_iterate(vpindexToConnect)) {
if (!ConnectTip(state, pindexConnect, pindexConnect == pindexMostWork ? pblock : std::shared_ptr<const CBlock>(), connectTrace, disconnectpool)) {
if (state.IsInvalid()) {
// The block violates a consensus rule.
if (state.GetResult() != BlockValidationResult::BLOCK_MUTATED) {
InvalidChainFound(vpindexToConnect.front());
}
state = BlockValidationState();
fInvalidFound = true;
fContinue = false;
break;
} else {
// A system error occurred (disk space, database error, ...).
// Make the mempool consistent with the current tip, just in case
// any observers try to use it before shutdown.
MaybeUpdateMempoolForReorg(disconnectpool, false);
return false;
}
} else {
PruneBlockIndexCandidates();
if (!pindexOldTip || m_chain.Tip()->nChainWork > pindexOldTip->nChainWork) {
// We're in a better position than we were. Return temporarily to release the lock.
fContinue = false;
break;
}
}
}
}
if (fBlocksDisconnected) {
// If any blocks were disconnected, disconnectpool may be non empty. Add
// any disconnected transactions back to the mempool.
MaybeUpdateMempoolForReorg(disconnectpool, true);
}
if (m_mempool) m_mempool->check(this->CoinsTip(), this->m_chain.Height() + 1);
CheckForkWarningConditions();
return true;
}
static SynchronizationState GetSynchronizationState(bool init)
{
if (!init) return SynchronizationState::POST_INIT;
if (::fReindex) return SynchronizationState::INIT_REINDEX;
return SynchronizationState::INIT_DOWNLOAD;
}
static bool NotifyHeaderTip(CChainState& chainstate) LOCKS_EXCLUDED(cs_main) {
bool fNotify = false;
bool fInitialBlockDownload = false;
static CBlockIndex* pindexHeaderOld = nullptr;
CBlockIndex* pindexHeader = nullptr;
{
LOCK(cs_main);
pindexHeader = chainstate.m_chainman.m_best_header;
if (pindexHeader != pindexHeaderOld) {
fNotify = true;
fInitialBlockDownload = chainstate.IsInitialBlockDownload();
pindexHeaderOld = pindexHeader;
}
}
// Send block tip changed notifications without cs_main
if (fNotify) {
uiInterface.NotifyHeaderTip(GetSynchronizationState(fInitialBlockDownload), pindexHeader);
}
return fNotify;
}
static void LimitValidationInterfaceQueue() LOCKS_EXCLUDED(cs_main) {
AssertLockNotHeld(cs_main);
if (GetMainSignals().CallbacksPending() > 10) {
SyncWithValidationInterfaceQueue();
}
}
bool CChainState::ActivateBestChain(BlockValidationState& state, std::shared_ptr<const CBlock> pblock)
{
AssertLockNotHeld(m_chainstate_mutex);
// Note that while we're often called here from ProcessNewBlock, this is
// far from a guarantee. Things in the P2P/RPC will often end up calling
// us in the middle of ProcessNewBlock - do not assume pblock is set
// sanely for performance or correctness!
AssertLockNotHeld(::cs_main);
// ABC maintains a fair degree of expensive-to-calculate internal state
// because this function periodically releases cs_main so that it does not lock up other threads for too long
// during large connects - and to allow for e.g. the callback queue to drain
// we use m_chainstate_mutex to enforce mutual exclusion so that only one caller may execute this function at a time
LOCK(m_chainstate_mutex);
CBlockIndex *pindexMostWork = nullptr;
CBlockIndex *pindexNewTip = nullptr;
int nStopAtHeight = gArgs.GetIntArg("-stopatheight", DEFAULT_STOPATHEIGHT);
do {
// Block until the validation queue drains. This should largely
// never happen in normal operation, however may happen during
// reindex, causing memory blowup if we run too far ahead.
// Note that if a validationinterface callback ends up calling
// ActivateBestChain this may lead to a deadlock! We should
// probably have a DEBUG_LOCKORDER test for this in the future.
LimitValidationInterfaceQueue();
{
LOCK(cs_main);
// Lock transaction pool for at least as long as it takes for connectTrace to be consumed
LOCK(MempoolMutex());
CBlockIndex* starting_tip = m_chain.Tip();
bool blocks_connected = false;
do {
// We absolutely may not unlock cs_main until we've made forward progress
// (with the exception of shutdown due to hardware issues, low disk space, etc).
ConnectTrace connectTrace; // Destructed before cs_main is unlocked
if (pindexMostWork == nullptr) {
pindexMostWork = FindMostWorkChain();
}
// Whether we have anything to do at all.
if (pindexMostWork == nullptr || pindexMostWork == m_chain.Tip()) {
break;
}
bool fInvalidFound = false;
std::shared_ptr<const CBlock> nullBlockPtr;
if (!ActivateBestChainStep(state, pindexMostWork, pblock && pblock->GetHash() == pindexMostWork->GetBlockHash() ? pblock : nullBlockPtr, fInvalidFound, connectTrace)) {
// A system error occurred
return false;
}
blocks_connected = true;
if (fInvalidFound) {
// Wipe cache, we may need another branch now.
pindexMostWork = nullptr;
}
pindexNewTip = m_chain.Tip();
for (const PerBlockConnectTrace& trace : connectTrace.GetBlocksConnected()) {
assert(trace.pblock && trace.pindex);
GetMainSignals().BlockConnected(trace.pblock, trace.pindex);
}
} while (!m_chain.Tip() || (starting_tip && CBlockIndexWorkComparator()(m_chain.Tip(), starting_tip)));
if (!blocks_connected) return true;
const CBlockIndex* pindexFork = m_chain.FindFork(starting_tip);
bool fInitialDownload = IsInitialBlockDownload();
// Notify external listeners about the new tip.
// Enqueue while holding cs_main to ensure that UpdatedBlockTip is called in the order in which blocks are connected
if (pindexFork != pindexNewTip) {
// Notify ValidationInterface subscribers
GetMainSignals().UpdatedBlockTip(pindexNewTip, pindexFork, fInitialDownload);
// Always notify the UI if a new block tip was connected
uiInterface.NotifyBlockTip(GetSynchronizationState(fInitialDownload), pindexNewTip);
}
}
// When we reach this point, we switched to a new tip (stored in pindexNewTip).
if (nStopAtHeight && pindexNewTip && pindexNewTip->nHeight >= nStopAtHeight) StartShutdown();
// We check shutdown only after giving ActivateBestChainStep a chance to run once so that we
// never shutdown before connecting the genesis block during LoadChainTip(). Previously this
// caused an assert() failure during shutdown in such cases as the UTXO DB flushing checks
// that the best block hash is non-null.
if (ShutdownRequested()) break;
} while (pindexNewTip != pindexMostWork);
CheckBlockIndex();
// Write changes periodically to disk, after relay.
if (!FlushStateToDisk(state, FlushStateMode::PERIODIC)) {
return false;
}
return true;
}
bool CChainState::PreciousBlock(BlockValidationState& state, CBlockIndex* pindex)
{
AssertLockNotHeld(m_chainstate_mutex);
AssertLockNotHeld(::cs_main);
{
LOCK(cs_main);
if (pindex->nChainWork < m_chain.Tip()->nChainWork) {
// Nothing to do, this block is not at the tip.
return true;
}
if (m_chain.Tip()->nChainWork > nLastPreciousChainwork) {
// The chain has been extended since the last call, reset the counter.
nBlockReverseSequenceId = -1;
}
nLastPreciousChainwork = m_chain.Tip()->nChainWork;
setBlockIndexCandidates.erase(pindex);
pindex->nSequenceId = nBlockReverseSequenceId;
if (nBlockReverseSequenceId > std::numeric_limits<int32_t>::min()) {
// We can't keep reducing the counter if somebody really wants to
// call preciousblock 2**31-1 times on the same set of tips...
nBlockReverseSequenceId--;
}
if (pindex->IsValid(BLOCK_VALID_TRANSACTIONS) && pindex->HaveTxsDownloaded()) {
setBlockIndexCandidates.insert(pindex);
PruneBlockIndexCandidates();
}
}
return ActivateBestChain(state, std::shared_ptr<const CBlock>());
}
bool CChainState::InvalidateBlock(BlockValidationState& state, CBlockIndex* pindex)
{
AssertLockNotHeld(m_chainstate_mutex);
AssertLockNotHeld(::cs_main);
// Genesis block can't be invalidated
assert(pindex);
if (pindex->nHeight == 0) return false;
CBlockIndex* to_mark_failed = pindex;
bool pindex_was_in_chain = false;
int disconnected = 0;
// We do not allow ActivateBestChain() to run while InvalidateBlock() is
// running, as that could cause the tip to change while we disconnect
// blocks.
LOCK(m_chainstate_mutex);
// We'll be acquiring and releasing cs_main below, to allow the validation
// callbacks to run. However, we should keep the block index in a
// consistent state as we disconnect blocks -- in particular we need to
// add equal-work blocks to setBlockIndexCandidates as we disconnect.
// To avoid walking the block index repeatedly in search of candidates,
// build a map once so that we can look up candidate blocks by chain
// work as we go.
std::multimap<const arith_uint256, CBlockIndex *> candidate_blocks_by_work;
{
LOCK(cs_main);
for (auto& entry : m_blockman.m_block_index) {
CBlockIndex* candidate = &entry.second;
// We don't need to put anything in our active chain into the
// multimap, because those candidates will be found and considered
// as we disconnect.
// Instead, consider only non-active-chain blocks that have at
// least as much work as where we expect the new tip to end up.
if (!m_chain.Contains(candidate) &&
!CBlockIndexWorkComparator()(candidate, pindex->pprev) &&
candidate->IsValid(BLOCK_VALID_TRANSACTIONS) &&
candidate->HaveTxsDownloaded()) {
candidate_blocks_by_work.insert(std::make_pair(candidate->nChainWork, candidate));
}
}
}
// Disconnect (descendants of) pindex, and mark them invalid.
while (true) {
if (ShutdownRequested()) break;
// Make sure the queue of validation callbacks doesn't grow unboundedly.
LimitValidationInterfaceQueue();
LOCK(cs_main);
// Lock for as long as disconnectpool is in scope to make sure MaybeUpdateMempoolForReorg is
// called after DisconnectTip without unlocking in between
LOCK(MempoolMutex());
if (!m_chain.Contains(pindex)) break;
pindex_was_in_chain = true;
CBlockIndex *invalid_walk_tip = m_chain.Tip();
// ActivateBestChain considers blocks already in m_chain
// unconditionally valid already, so force disconnect away from it.
DisconnectedBlockTransactions disconnectpool;
bool ret = DisconnectTip(state, &disconnectpool);
// DisconnectTip will add transactions to disconnectpool.
// Adjust the mempool to be consistent with the new tip, adding
// transactions back to the mempool if disconnecting was successful,
// and we're not doing a very deep invalidation (in which case
// keeping the mempool up to date is probably futile anyway).
MaybeUpdateMempoolForReorg(disconnectpool, /* fAddToMempool = */ (++disconnected <= 10) && ret);
if (!ret) return false;
assert(invalid_walk_tip->pprev == m_chain.Tip());
// We immediately mark the disconnected blocks as invalid.
// This prevents a case where pruned nodes may fail to invalidateblock
// and be left unable to start as they have no tip candidates (as there
// are no blocks that meet the "have data and are not invalid per
// nStatus" criteria for inclusion in setBlockIndexCandidates).
invalid_walk_tip->nStatus |= BLOCK_FAILED_VALID;
m_blockman.m_dirty_blockindex.insert(invalid_walk_tip);
setBlockIndexCandidates.erase(invalid_walk_tip);
setBlockIndexCandidates.insert(invalid_walk_tip->pprev);
if (invalid_walk_tip->pprev == to_mark_failed && (to_mark_failed->nStatus & BLOCK_FAILED_VALID)) {
// We only want to mark the last disconnected block as BLOCK_FAILED_VALID; its children
// need to be BLOCK_FAILED_CHILD instead.
to_mark_failed->nStatus = (to_mark_failed->nStatus ^ BLOCK_FAILED_VALID) | BLOCK_FAILED_CHILD;
m_blockman.m_dirty_blockindex.insert(to_mark_failed);
}
// Add any equal or more work headers to setBlockIndexCandidates
auto candidate_it = candidate_blocks_by_work.lower_bound(invalid_walk_tip->pprev->nChainWork);
while (candidate_it != candidate_blocks_by_work.end()) {
if (!CBlockIndexWorkComparator()(candidate_it->second, invalid_walk_tip->pprev)) {
setBlockIndexCandidates.insert(candidate_it->second);
candidate_it = candidate_blocks_by_work.erase(candidate_it);
} else {
++candidate_it;
}
}
// Track the last disconnected block, so we can correct its BLOCK_FAILED_CHILD status in future
// iterations, or, if it's the last one, call InvalidChainFound on it.
to_mark_failed = invalid_walk_tip;
}
CheckBlockIndex();
{
LOCK(cs_main);
if (m_chain.Contains(to_mark_failed)) {
// If the to-be-marked invalid block is in the active chain, something is interfering and we can't proceed.
return false;
}
// Mark pindex (or the last disconnected block) as invalid, even when it never was in the main chain
to_mark_failed->nStatus |= BLOCK_FAILED_VALID;
m_blockman.m_dirty_blockindex.insert(to_mark_failed);
setBlockIndexCandidates.erase(to_mark_failed);
m_chainman.m_failed_blocks.insert(to_mark_failed);
// If any new blocks somehow arrived while we were disconnecting
// (above), then the pre-calculation of what should go into
// setBlockIndexCandidates may have missed entries. This would
// technically be an inconsistency in the block index, but if we clean
// it up here, this should be an essentially unobservable error.
// Loop back over all block index entries and add any missing entries
// to setBlockIndexCandidates.
for (auto& [_, block_index] : m_blockman.m_block_index) {
if (block_index.IsValid(BLOCK_VALID_TRANSACTIONS) && block_index.HaveTxsDownloaded() && !setBlockIndexCandidates.value_comp()(&block_index, m_chain.Tip())) {
setBlockIndexCandidates.insert(&block_index);
}
}
InvalidChainFound(to_mark_failed);
}
// Only notify about a new block tip if the active chain was modified.
if (pindex_was_in_chain) {
uiInterface.NotifyBlockTip(GetSynchronizationState(IsInitialBlockDownload()), to_mark_failed->pprev);
}
return true;
}
void CChainState::ResetBlockFailureFlags(CBlockIndex *pindex) {
AssertLockHeld(cs_main);
int nHeight = pindex->nHeight;
// Remove the invalidity flag from this block and all its descendants.
for (auto& [_, block_index] : m_blockman.m_block_index) {
if (!block_index.IsValid() && block_index.GetAncestor(nHeight) == pindex) {
block_index.nStatus &= ~BLOCK_FAILED_MASK;
m_blockman.m_dirty_blockindex.insert(&block_index);
if (block_index.IsValid(BLOCK_VALID_TRANSACTIONS) && block_index.HaveTxsDownloaded() && setBlockIndexCandidates.value_comp()(m_chain.Tip(), &block_index)) {
setBlockIndexCandidates.insert(&block_index);
}
if (&block_index == m_chainman.m_best_invalid) {
// Reset invalid block marker if it was pointing to one of those.
m_chainman.m_best_invalid = nullptr;
}
m_chainman.m_failed_blocks.erase(&block_index);
}
}
// Remove the invalidity flag from all ancestors too.
while (pindex != nullptr) {
if (pindex->nStatus & BLOCK_FAILED_MASK) {
pindex->nStatus &= ~BLOCK_FAILED_MASK;
m_blockman.m_dirty_blockindex.insert(pindex);
m_chainman.m_failed_blocks.erase(pindex);
}
pindex = pindex->pprev;
}
}
/** Mark a block as having its data received and checked (up to BLOCK_VALID_TRANSACTIONS). */
void CChainState::ReceivedBlockTransactions(const CBlock& block, CBlockIndex* pindexNew, const FlatFilePos& pos)
{
AssertLockHeld(cs_main);
pindexNew->nTx = block.vtx.size();
pindexNew->nChainTx = 0;
pindexNew->nFile = pos.nFile;
pindexNew->nDataPos = pos.nPos;
pindexNew->nUndoPos = 0;
pindexNew->nStatus |= BLOCK_HAVE_DATA;
if (DeploymentActiveAt(*pindexNew, m_chainman, Consensus::DEPLOYMENT_SEGWIT)) {
pindexNew->nStatus |= BLOCK_OPT_WITNESS;
}
pindexNew->RaiseValidity(BLOCK_VALID_TRANSACTIONS);
m_blockman.m_dirty_blockindex.insert(pindexNew);
if (pindexNew->pprev == nullptr || pindexNew->pprev->HaveTxsDownloaded()) {
// If pindexNew is the genesis block or all parents are BLOCK_VALID_TRANSACTIONS.
std::deque<CBlockIndex*> queue;
queue.push_back(pindexNew);
// Recursively process any descendant blocks that now may be eligible to be connected.
while (!queue.empty()) {
CBlockIndex *pindex = queue.front();
queue.pop_front();
pindex->nChainTx = (pindex->pprev ? pindex->pprev->nChainTx : 0) + pindex->nTx;
pindex->nSequenceId = nBlockSequenceId++;
if (m_chain.Tip() == nullptr || !setBlockIndexCandidates.value_comp()(pindex, m_chain.Tip())) {
setBlockIndexCandidates.insert(pindex);
}
std::pair<std::multimap<CBlockIndex*, CBlockIndex*>::iterator, std::multimap<CBlockIndex*, CBlockIndex*>::iterator> range = m_blockman.m_blocks_unlinked.equal_range(pindex);
while (range.first != range.second) {
std::multimap<CBlockIndex*, CBlockIndex*>::iterator it = range.first;
queue.push_back(it->second);
range.first++;
m_blockman.m_blocks_unlinked.erase(it);
}
}
} else {
if (pindexNew->pprev && pindexNew->pprev->IsValid(BLOCK_VALID_TREE)) {
m_blockman.m_blocks_unlinked.insert(std::make_pair(pindexNew->pprev, pindexNew));
}
}
}
static bool CheckBlockHeader(const CBlockHeader& block, BlockValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW = true)
{
// Check proof of work matches claimed amount
if (fCheckPOW && !CheckProofOfWork(block.GetHash(), block.nBits, consensusParams))
return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER, "high-hash", "proof of work failed");
return true;
}
bool CheckBlock(const CBlock& block, BlockValidationState& state, const Consensus::Params& consensusParams, bool fCheckPOW, bool fCheckMerkleRoot)
{
// These are checks that are independent of context.
if (block.fChecked)
return true;
// Check that the header is valid (particularly PoW). This is mostly
// redundant with the call in AcceptBlockHeader.
if (!CheckBlockHeader(block, state, consensusParams, fCheckPOW))
return false;
// Signet only: check block solution
if (consensusParams.signet_blocks && fCheckPOW && !CheckSignetBlockSolution(block, consensusParams)) {
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-signet-blksig", "signet block signature validation failure");
}
// Check the merkle root.
if (fCheckMerkleRoot) {
bool mutated;
uint256 hashMerkleRoot2 = BlockMerkleRoot(block, &mutated);
if (block.hashMerkleRoot != hashMerkleRoot2)
return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-txnmrklroot", "hashMerkleRoot mismatch");
// Check for merkle tree malleability (CVE-2012-2459): repeating sequences
// of transactions in a block without affecting the merkle root of a block,
// while still invalidating it.
if (mutated)
return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-txns-duplicate", "duplicate transaction");
}
// All potential-corruption validation must be done before we do any
// transaction validation, as otherwise we may mark the header as invalid
// because we receive the wrong transactions for it.
// Note that witness malleability is checked in ContextualCheckBlock, so no
// checks that use witness data may be performed here.
// Size limits
if (block.vtx.empty() || block.vtx.size() * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT || ::GetSerializeSize(block, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-blk-length", "size limits failed");
// First transaction must be coinbase, the rest must not be
if (block.vtx.empty() || !block.vtx[0]->IsCoinBase())
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-missing", "first tx is not coinbase");
for (unsigned int i = 1; i < block.vtx.size(); i++)
if (block.vtx[i]->IsCoinBase())
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-multiple", "more than one coinbase");
// Check transactions
// Must check for duplicate inputs (see CVE-2018-17144)
for (const auto& tx : block.vtx) {
TxValidationState tx_state;
if (!CheckTransaction(*tx, tx_state)) {
// CheckBlock() does context-free validation checks. The only
// possible failures are consensus failures.
assert(tx_state.GetResult() == TxValidationResult::TX_CONSENSUS);
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, tx_state.GetRejectReason(),
strprintf("Transaction check failed (tx hash %s) %s", tx->GetHash().ToString(), tx_state.GetDebugMessage()));
}
}
unsigned int nSigOps = 0;
for (const auto& tx : block.vtx)
{
nSigOps += GetLegacySigOpCount(*tx);
}
if (nSigOps * WITNESS_SCALE_FACTOR > MAX_BLOCK_SIGOPS_COST)
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-blk-sigops", "out-of-bounds SigOpCount");
if (fCheckPOW && fCheckMerkleRoot)
block.fChecked = true;
return true;
}
void ChainstateManager::UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev) const
{
int commitpos = GetWitnessCommitmentIndex(block);
static const std::vector<unsigned char> nonce(32, 0x00);
if (commitpos != NO_WITNESS_COMMITMENT && DeploymentActiveAfter(pindexPrev, *this, Consensus::DEPLOYMENT_SEGWIT) && !block.vtx[0]->HasWitness()) {
CMutableTransaction tx(*block.vtx[0]);
tx.vin[0].scriptWitness.stack.resize(1);
tx.vin[0].scriptWitness.stack[0] = nonce;
block.vtx[0] = MakeTransactionRef(std::move(tx));
}
}
std::vector<unsigned char> ChainstateManager::GenerateCoinbaseCommitment(CBlock& block, const CBlockIndex* pindexPrev) const
{
std::vector<unsigned char> commitment;
int commitpos = GetWitnessCommitmentIndex(block);
std::vector<unsigned char> ret(32, 0x00);
if (commitpos == NO_WITNESS_COMMITMENT) {
uint256 witnessroot = BlockWitnessMerkleRoot(block, nullptr);
CHash256().Write(witnessroot).Write(ret).Finalize(witnessroot);
CTxOut out;
out.nValue = 0;
out.scriptPubKey.resize(MINIMUM_WITNESS_COMMITMENT);
out.scriptPubKey[0] = OP_RETURN;
out.scriptPubKey[1] = 0x24;
out.scriptPubKey[2] = 0xaa;
out.scriptPubKey[3] = 0x21;
out.scriptPubKey[4] = 0xa9;
out.scriptPubKey[5] = 0xed;
memcpy(&out.scriptPubKey[6], witnessroot.begin(), 32);
commitment = std::vector<unsigned char>(out.scriptPubKey.begin(), out.scriptPubKey.end());
CMutableTransaction tx(*block.vtx[0]);
tx.vout.push_back(out);
block.vtx[0] = MakeTransactionRef(std::move(tx));
}
UpdateUncommittedBlockStructures(block, pindexPrev);
return commitment;
}
/** Context-dependent validity checks.
* By "context", we mean only the previous block headers, but not the UTXO
* set; UTXO-related validity checks are done in ConnectBlock().
* NOTE: This function is not currently invoked by ConnectBlock(), so we
* should consider upgrade issues if we change which consensus rules are
* enforced in this function (eg by adding a new consensus rule). See comment
* in ConnectBlock().
* Note that -reindex-chainstate skips the validation that happens here!
*/
static bool ContextualCheckBlockHeader(const CBlockHeader& block, BlockValidationState& state, BlockManager& blockman, const ChainstateManager& chainman, const CBlockIndex* pindexPrev, int64_t nAdjustedTime) EXCLUSIVE_LOCKS_REQUIRED(::cs_main)
{
AssertLockHeld(::cs_main);
assert(pindexPrev != nullptr);
const int nHeight = pindexPrev->nHeight + 1;
// Check proof of work
const Consensus::Params& consensusParams = chainman.GetConsensus();
if (block.nBits != GetNextWorkRequired(pindexPrev, &block, consensusParams))
return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER, "bad-diffbits", "incorrect proof of work");
// Check against checkpoints
if (fCheckpointsEnabled) {
// Don't accept any forks from the main chain prior to last checkpoint.
// GetLastCheckpoint finds the last checkpoint in MapCheckpoints that's in our
// BlockIndex().
const CBlockIndex* pcheckpoint = blockman.GetLastCheckpoint(chainman.GetParams().Checkpoints());
if (pcheckpoint && nHeight < pcheckpoint->nHeight) {
LogPrintf("ERROR: %s: forked chain older than last checkpoint (height %d)\n", __func__, nHeight);
return state.Invalid(BlockValidationResult::BLOCK_CHECKPOINT, "bad-fork-prior-to-checkpoint");
}
}
// Check timestamp against prev
if (block.GetBlockTime() <= pindexPrev->GetMedianTimePast())
return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER, "time-too-old", "block's timestamp is too early");
// Check timestamp
if (block.GetBlockTime() > nAdjustedTime + MAX_FUTURE_BLOCK_TIME)
return state.Invalid(BlockValidationResult::BLOCK_TIME_FUTURE, "time-too-new", "block timestamp too far in the future");
// Reject blocks with outdated version
if ((block.nVersion < 2 && DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_HEIGHTINCB)) ||
(block.nVersion < 3 && DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_DERSIG)) ||
(block.nVersion < 4 && DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_CLTV))) {
return state.Invalid(BlockValidationResult::BLOCK_INVALID_HEADER, strprintf("bad-version(0x%08x)", block.nVersion),
strprintf("rejected nVersion=0x%08x block", block.nVersion));
}
return true;
}
/** NOTE: This function is not currently invoked by ConnectBlock(), so we
* should consider upgrade issues if we change which consensus rules are
* enforced in this function (eg by adding a new consensus rule). See comment
* in ConnectBlock().
* Note that -reindex-chainstate skips the validation that happens here!
*/
static bool ContextualCheckBlock(const CBlock& block, BlockValidationState& state, const ChainstateManager& chainman, const CBlockIndex* pindexPrev)
{
const int nHeight = pindexPrev == nullptr ? 0 : pindexPrev->nHeight + 1;
// Enforce BIP113 (Median Time Past).
int nLockTimeFlags = 0;
if (DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_CSV)) {
assert(pindexPrev != nullptr);
nLockTimeFlags |= LOCKTIME_MEDIAN_TIME_PAST;
}
int64_t nLockTimeCutoff = (nLockTimeFlags & LOCKTIME_MEDIAN_TIME_PAST)
? pindexPrev->GetMedianTimePast()
: block.GetBlockTime();
// Check that all transactions are finalized
for (const auto& tx : block.vtx) {
if (!IsFinalTx(*tx, nHeight, nLockTimeCutoff)) {
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-txns-nonfinal", "non-final transaction");
}
}
// Enforce rule that the coinbase starts with serialized block height
if (DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_HEIGHTINCB))
{
CScript expect = CScript() << nHeight;
if (block.vtx[0]->vin[0].scriptSig.size() < expect.size() ||
!std::equal(expect.begin(), expect.end(), block.vtx[0]->vin[0].scriptSig.begin())) {
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-cb-height", "block height mismatch in coinbase");
}
}
// Validation for witness commitments.
// * We compute the witness hash (which is the hash including witnesses) of all the block's transactions, except the
// coinbase (where 0x0000....0000 is used instead).
// * The coinbase scriptWitness is a stack of a single 32-byte vector, containing a witness reserved value (unconstrained).
// * We build a merkle tree with all those witness hashes as leaves (similar to the hashMerkleRoot in the block header).
// * There must be at least one output whose scriptPubKey is a single 36-byte push, the first 4 bytes of which are
// {0xaa, 0x21, 0xa9, 0xed}, and the following 32 bytes are SHA256^2(witness root, witness reserved value). In case there are
// multiple, the last one is used.
bool fHaveWitness = false;
if (DeploymentActiveAfter(pindexPrev, chainman, Consensus::DEPLOYMENT_SEGWIT)) {
int commitpos = GetWitnessCommitmentIndex(block);
if (commitpos != NO_WITNESS_COMMITMENT) {
bool malleated = false;
uint256 hashWitness = BlockWitnessMerkleRoot(block, &malleated);
// The malleation check is ignored; as the transaction tree itself
// already does not permit it, it is impossible to trigger in the
// witness tree.
if (block.vtx[0]->vin[0].scriptWitness.stack.size() != 1 || block.vtx[0]->vin[0].scriptWitness.stack[0].size() != 32) {
return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-witness-nonce-size", strprintf("%s : invalid witness reserved value size", __func__));
}
CHash256().Write(hashWitness).Write(block.vtx[0]->vin[0].scriptWitness.stack[0]).Finalize(hashWitness);
if (memcmp(hashWitness.begin(), &block.vtx[0]->vout[commitpos].scriptPubKey[6], 32)) {
return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "bad-witness-merkle-match", strprintf("%s : witness merkle commitment mismatch", __func__));
}
fHaveWitness = true;
}
}
// No witness data is allowed in blocks that don't commit to witness data, as this would otherwise leave room for spam
if (!fHaveWitness) {
for (const auto& tx : block.vtx) {
if (tx->HasWitness()) {
return state.Invalid(BlockValidationResult::BLOCK_MUTATED, "unexpected-witness", strprintf("%s : unexpected witness data found", __func__));
}
}
}
// After the coinbase witness reserved value and commitment are verified,
// we can check if the block weight passes (before we've checked the
// coinbase witness, it would be possible for the weight to be too
// large by filling up the coinbase witness, which doesn't change
// the block hash, so we couldn't mark the block as permanently
// failed).
if (GetBlockWeight(block) > MAX_BLOCK_WEIGHT) {
return state.Invalid(BlockValidationResult::BLOCK_CONSENSUS, "bad-blk-weight", strprintf("%s : weight limit failed", __func__));
}
return true;
}
bool ChainstateManager::AcceptBlockHeader(const CBlockHeader& block, BlockValidationState& state, CBlockIndex** ppindex)
{
AssertLockHeld(cs_main);
// Check for duplicate
uint256 hash = block.GetHash();
BlockMap::iterator miSelf{m_blockman.m_block_index.find(hash)};
if (hash != GetConsensus().hashGenesisBlock) {
if (miSelf != m_blockman.m_block_index.end()) {
// Block header is already known.
CBlockIndex* pindex = &(miSelf->second);
if (ppindex)
*ppindex = pindex;
if (pindex->nStatus & BLOCK_FAILED_MASK) {
LogPrint(BCLog::VALIDATION, "%s: block %s is marked invalid\n", __func__, hash.ToString());
return state.Invalid(BlockValidationResult::BLOCK_CACHED_INVALID, "duplicate");
}
return true;
}
if (!CheckBlockHeader(block, state, GetConsensus())) {
LogPrint(BCLog::VALIDATION, "%s: Consensus::CheckBlockHeader: %s, %s\n", __func__, hash.ToString(), state.ToString());
return false;
}
// Get prev block index
CBlockIndex* pindexPrev = nullptr;
BlockMap::iterator mi{m_blockman.m_block_index.find(block.hashPrevBlock)};
if (mi == m_blockman.m_block_index.end()) {
LogPrint(BCLog::VALIDATION, "%s: %s prev block not found\n", __func__, hash.ToString());
return state.Invalid(BlockValidationResult::BLOCK_MISSING_PREV, "prev-blk-not-found");
}
pindexPrev = &((*mi).second);
if (pindexPrev->nStatus & BLOCK_FAILED_MASK) {
LogPrint(BCLog::VALIDATION, "%s: %s prev block invalid\n", __func__, hash.ToString());
return state.Invalid(BlockValidationResult::BLOCK_INVALID_PREV, "bad-prevblk");
}
if (!ContextualCheckBlockHeader(block, state, m_blockman, *this, pindexPrev, m_adjusted_time_callback())) {
LogPrint(BCLog::VALIDATION, "%s: Consensus::ContextualCheckBlockHeader: %s, %s\n", __func__, hash.ToString(), state.ToString());
return false;
}
/* Determine if this block descends from any block which has been found
* invalid (m_failed_blocks), then mark pindexPrev and any blocks between
* them as failed. For example:
*
* D3
* /
* B2 - C2
* / \
* A D2 - E2 - F2
* \
* B1 - C1 - D1 - E1
*
* In the case that we attempted to reorg from E1 to F2, only to find
* C2 to be invalid, we would mark D2, E2, and F2 as BLOCK_FAILED_CHILD
* but NOT D3 (it was not in any of our candidate sets at the time).
*
* In any case D3 will also be marked as BLOCK_FAILED_CHILD at restart
* in LoadBlockIndex.
*/
if (!pindexPrev->IsValid(BLOCK_VALID_SCRIPTS)) {
// The above does not mean "invalid": it checks if the previous block
// hasn't been validated up to BLOCK_VALID_SCRIPTS. This is a performance
// optimization, in the common case of adding a new block to the tip,
// we don't need to iterate over the failed blocks list.
for (const CBlockIndex* failedit : m_failed_blocks) {
if (pindexPrev->GetAncestor(failedit->nHeight) == failedit) {
assert(failedit->nStatus & BLOCK_FAILED_VALID);
CBlockIndex* invalid_walk = pindexPrev;
while (invalid_walk != failedit) {
invalid_walk->nStatus |= BLOCK_FAILED_CHILD;
m_blockman.m_dirty_blockindex.insert(invalid_walk);
invalid_walk = invalid_walk->pprev;
}
LogPrint(BCLog::VALIDATION, "%s: %s prev block invalid\n", __func__, hash.ToString());
return state.Invalid(BlockValidationResult::BLOCK_INVALID_PREV, "bad-prevblk");
}
}
}
}
CBlockIndex* pindex{m_blockman.AddToBlockIndex(block, m_best_header)};
if (ppindex)
*ppindex = pindex;
return true;
}
// Exposed wrapper for AcceptBlockHeader
bool ChainstateManager::ProcessNewBlockHeaders(const std::vector<CBlockHeader>& headers, BlockValidationState& state, const CBlockIndex** ppindex)
{
AssertLockNotHeld(cs_main);
{
LOCK(cs_main);
for (const CBlockHeader& header : headers) {
CBlockIndex *pindex = nullptr; // Use a temp pindex instead of ppindex to avoid a const_cast
bool accepted{AcceptBlockHeader(header, state, &pindex)};
ActiveChainstate().CheckBlockIndex();
if (!accepted) {
return false;
}
if (ppindex) {
*ppindex = pindex;
}
}
}
if (NotifyHeaderTip(ActiveChainstate())) {
if (ActiveChainstate().IsInitialBlockDownload() && ppindex && *ppindex) {
const CBlockIndex& last_accepted{**ppindex};
const int64_t blocks_left{(GetTime() - last_accepted.GetBlockTime()) / GetConsensus().nPowTargetSpacing};
const double progress{100.0 * last_accepted.nHeight / (last_accepted.nHeight + blocks_left)};
LogPrintf("Synchronizing blockheaders, height: %d (~%.2f%%)\n", last_accepted.nHeight, progress);
}
}
return true;
}
/** Store block on disk. If dbp is non-nullptr, the file is known to already reside on disk */
bool CChainState::AcceptBlock(const std::shared_ptr<const CBlock>& pblock, BlockValidationState& state, CBlockIndex** ppindex, bool fRequested, const FlatFilePos* dbp, bool* fNewBlock)
{
const CBlock& block = *pblock;
if (fNewBlock) *fNewBlock = false;
AssertLockHeld(cs_main);
CBlockIndex *pindexDummy = nullptr;
CBlockIndex *&pindex = ppindex ? *ppindex : pindexDummy;
bool accepted_header{m_chainman.AcceptBlockHeader(block, state, &pindex)};
CheckBlockIndex();
if (!accepted_header)
return false;
// Try to process all requested blocks that we don't have, but only
// process an unrequested block if it's new and has enough work to
// advance our tip, and isn't too many blocks ahead.
bool fAlreadyHave = pindex->nStatus & BLOCK_HAVE_DATA;
bool fHasMoreOrSameWork = (m_chain.Tip() ? pindex->nChainWork >= m_chain.Tip()->nChainWork : true);
// Blocks that are too out-of-order needlessly limit the effectiveness of
// pruning, because pruning will not delete block files that contain any
// blocks which are too close in height to the tip. Apply this test
// regardless of whether pruning is enabled; it should generally be safe to
// not process unrequested blocks.
bool fTooFarAhead{pindex->nHeight > m_chain.Height() + int(MIN_BLOCKS_TO_KEEP)};
// TODO: Decouple this function from the block download logic by removing fRequested
// This requires some new chain data structure to efficiently look up if a
// block is in a chain leading to a candidate for best tip, despite not
// being such a candidate itself.
// Note that this would break the getblockfrompeer RPC
// TODO: deal better with return value and error conditions for duplicate
// and unrequested blocks.
if (fAlreadyHave) return true;
if (!fRequested) { // If we didn't ask for it:
if (pindex->nTx != 0) return true; // This is a previously-processed block that was pruned
if (!fHasMoreOrSameWork) return true; // Don't process less-work chains
if (fTooFarAhead) return true; // Block height is too high
// Protect against DoS attacks from low-work chains.
// If our tip is behind, a peer could try to send us
// low-work blocks on a fake chain that we would never
// request; don't process these.
if (pindex->nChainWork < nMinimumChainWork) return true;
}
if (!CheckBlock(block, state, m_params.GetConsensus()) ||
!ContextualCheckBlock(block, state, m_chainman, pindex->pprev)) {
if (state.IsInvalid() && state.GetResult() != BlockValidationResult::BLOCK_MUTATED) {
pindex->nStatus |= BLOCK_FAILED_VALID;
m_blockman.m_dirty_blockindex.insert(pindex);
}
return error("%s: %s", __func__, state.ToString());
}
// Header is valid/has work, merkle tree and segwit merkle tree are good...RELAY NOW
// (but if it does not build on our best tip, let the SendMessages loop relay it)
if (!IsInitialBlockDownload() && m_chain.Tip() == pindex->pprev)
GetMainSignals().NewPoWValidBlock(pindex, pblock);
// Write block to history file
if (fNewBlock) *fNewBlock = true;
try {
FlatFilePos blockPos{m_blockman.SaveBlockToDisk(block, pindex->nHeight, m_chain, m_params, dbp)};
if (blockPos.IsNull()) {
state.Error(strprintf("%s: Failed to find position to write new block to disk", __func__));
return false;
}
ReceivedBlockTransactions(block, pindex, blockPos);
} catch (const std::runtime_error& e) {
return AbortNode(state, std::string("System error: ") + e.what());
}
FlushStateToDisk(state, FlushStateMode::NONE);
CheckBlockIndex();
return true;
}
bool ChainstateManager::ProcessNewBlock(const std::shared_ptr<const CBlock>& block, bool force_processing, bool* new_block)
{
AssertLockNotHeld(cs_main);
{
CBlockIndex *pindex = nullptr;
if (new_block) *new_block = false;
BlockValidationState state;
// CheckBlock() does not support multi-threaded block validation because CBlock::fChecked can cause data race.
// Therefore, the following critical section must include the CheckBlock() call as well.
LOCK(cs_main);
// Skipping AcceptBlock() for CheckBlock() failures means that we will never mark a block as invalid if
// CheckBlock() fails. This is protective against consensus failure if there are any unknown forms of block
// malleability that cause CheckBlock() to fail; see e.g. CVE-2012-2459 and
// https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2019-February/016697.html. Because CheckBlock() is
// not very expensive, the anti-DoS benefits of caching failure (of a definitely-invalid block) are not substantial.
bool ret = CheckBlock(*block, state, GetConsensus());
if (ret) {
// Store to disk
ret = ActiveChainstate().AcceptBlock(block, state, &pindex, force_processing, nullptr, new_block);
}
if (!ret) {
GetMainSignals().BlockChecked(*block, state);
return error("%s: AcceptBlock FAILED (%s)", __func__, state.ToString());
}
}
NotifyHeaderTip(ActiveChainstate());
BlockValidationState state; // Only used to report errors, not invalidity - ignore it
if (!ActiveChainstate().ActivateBestChain(state, block)) {
return error("%s: ActivateBestChain failed (%s)", __func__, state.ToString());
}
return true;
}
MempoolAcceptResult ChainstateManager::ProcessTransaction(const CTransactionRef& tx, bool test_accept)
{
AssertLockHeld(cs_main);
CChainState& active_chainstate = ActiveChainstate();
if (!active_chainstate.GetMempool()) {
TxValidationState state;
state.Invalid(TxValidationResult::TX_NO_MEMPOOL, "no-mempool");
return MempoolAcceptResult::Failure(state);
}
auto result = AcceptToMemoryPool(active_chainstate, tx, GetTime(), /*bypass_limits=*/ false, test_accept);
active_chainstate.GetMempool()->check(active_chainstate.CoinsTip(), active_chainstate.m_chain.Height() + 1);
return result;
}
bool TestBlockValidity(BlockValidationState& state,
const CChainParams& chainparams,
CChainState& chainstate,
const CBlock& block,
CBlockIndex* pindexPrev,
const std::function<int64_t()>& adjusted_time_callback,
bool fCheckPOW,
bool fCheckMerkleRoot)
{
AssertLockHeld(cs_main);
assert(pindexPrev && pindexPrev == chainstate.m_chain.Tip());
CCoinsViewCache viewNew(&chainstate.CoinsTip());
uint256 block_hash(block.GetHash());
CBlockIndex indexDummy(block);
indexDummy.pprev = pindexPrev;
indexDummy.nHeight = pindexPrev->nHeight + 1;
indexDummy.phashBlock = &block_hash;
// NOTE: CheckBlockHeader is called by CheckBlock
if (!ContextualCheckBlockHeader(block, state, chainstate.m_blockman, chainstate.m_chainman, pindexPrev, adjusted_time_callback()))
return error("%s: Consensus::ContextualCheckBlockHeader: %s", __func__, state.ToString());
if (!CheckBlock(block, state, chainparams.GetConsensus(), fCheckPOW, fCheckMerkleRoot))
return error("%s: Consensus::CheckBlock: %s", __func__, state.ToString());
if (!ContextualCheckBlock(block, state, chainstate.m_chainman, pindexPrev))
return error("%s: Consensus::ContextualCheckBlock: %s", __func__, state.ToString());
if (!chainstate.ConnectBlock(block, state, &indexDummy, viewNew, true)) {
return false;
}
assert(state.IsValid());
return true;
}
/* This function is called from the RPC code for pruneblockchain */
void PruneBlockFilesManual(CChainState& active_chainstate, int nManualPruneHeight)
{
BlockValidationState state;
if (!active_chainstate.FlushStateToDisk(
state, FlushStateMode::NONE, nManualPruneHeight)) {
LogPrintf("%s: failed to flush state (%s)\n", __func__, state.ToString());
}
}
void CChainState::LoadMempool(const ArgsManager& args)
{
if (!m_mempool) return;
if (args.GetBoolArg("-persistmempool", DEFAULT_PERSIST_MEMPOOL)) {
::LoadMempool(*m_mempool, *this);
}
m_mempool->SetIsLoaded(!ShutdownRequested());
}
bool CChainState::LoadChainTip()
{
AssertLockHeld(cs_main);
const CCoinsViewCache& coins_cache = CoinsTip();
assert(!coins_cache.GetBestBlock().IsNull()); // Never called when the coins view is empty
const CBlockIndex* tip = m_chain.Tip();
if (tip && tip->GetBlockHash() == coins_cache.GetBestBlock()) {
return true;
}
// Load pointer to end of best chain
CBlockIndex* pindex = m_blockman.LookupBlockIndex(coins_cache.GetBestBlock());
if (!pindex) {
return false;
}
m_chain.SetTip(pindex);
PruneBlockIndexCandidates();
tip = m_chain.Tip();
LogPrintf("Loaded best chain: hashBestChain=%s height=%d date=%s progress=%f\n",
tip->GetBlockHash().ToString(),
m_chain.Height(),
FormatISO8601DateTime(tip->GetBlockTime()),
GuessVerificationProgress(m_params.TxData(), tip));
return true;
}
CVerifyDB::CVerifyDB()
{
uiInterface.ShowProgress(_("Verifying blocks…").translated, 0, false);
}
CVerifyDB::~CVerifyDB()
{
uiInterface.ShowProgress("", 100, false);
}
bool CVerifyDB::VerifyDB(
CChainState& chainstate,
const Consensus::Params& consensus_params,
CCoinsView& coinsview,
int nCheckLevel, int nCheckDepth)
{
AssertLockHeld(cs_main);
if (chainstate.m_chain.Tip() == nullptr || chainstate.m_chain.Tip()->pprev == nullptr) {
return true;
}
// Verify blocks in the best chain
if (nCheckDepth <= 0 || nCheckDepth > chainstate.m_chain.Height()) {
nCheckDepth = chainstate.m_chain.Height();
}
nCheckLevel = std::max(0, std::min(4, nCheckLevel));
LogPrintf("Verifying last %i blocks at level %i\n", nCheckDepth, nCheckLevel);
CCoinsViewCache coins(&coinsview);
CBlockIndex* pindex;
CBlockIndex* pindexFailure = nullptr;
int nGoodTransactions = 0;
BlockValidationState state;
int reportDone = 0;
LogPrintf("[0%%]..."); /* Continued */
const bool is_snapshot_cs{!chainstate.m_from_snapshot_blockhash};
for (pindex = chainstate.m_chain.Tip(); pindex && pindex->pprev; pindex = pindex->pprev) {
const int percentageDone = std::max(1, std::min(99, (int)(((double)(chainstate.m_chain.Height() - pindex->nHeight)) / (double)nCheckDepth * (nCheckLevel >= 4 ? 50 : 100))));
if (reportDone < percentageDone / 10) {
// report every 10% step
LogPrintf("[%d%%]...", percentageDone); /* Continued */
reportDone = percentageDone / 10;
}
uiInterface.ShowProgress(_("Verifying blocks…").translated, percentageDone, false);
if (pindex->nHeight <= chainstate.m_chain.Height() - nCheckDepth) {
break;
}
if ((fPruneMode || is_snapshot_cs) && !(pindex->nStatus & BLOCK_HAVE_DATA)) {
// If pruning or running under an assumeutxo snapshot, only go
// back as far as we have data.
LogPrintf("VerifyDB(): block verification stopping at height %d (pruning, no data)\n", pindex->nHeight);
break;
}
CBlock block;
// check level 0: read from disk
if (!ReadBlockFromDisk(block, pindex, consensus_params)) {
return error("VerifyDB(): *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
}
// check level 1: verify block validity
if (nCheckLevel >= 1 && !CheckBlock(block, state, consensus_params)) {
return error("%s: *** found bad block at %d, hash=%s (%s)\n", __func__,
pindex->nHeight, pindex->GetBlockHash().ToString(), state.ToString());
}
// check level 2: verify undo validity
if (nCheckLevel >= 2 && pindex) {
CBlockUndo undo;
if (!pindex->GetUndoPos().IsNull()) {
if (!UndoReadFromDisk(undo, pindex)) {
return error("VerifyDB(): *** found bad undo data at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString());
}
}
}
// check level 3: check for inconsistencies during memory-only disconnect of tip blocks
size_t curr_coins_usage = coins.DynamicMemoryUsage() + chainstate.CoinsTip().DynamicMemoryUsage();
if (nCheckLevel >= 3 && curr_coins_usage <= chainstate.m_coinstip_cache_size_bytes) {
assert(coins.GetBestBlock() == pindex->GetBlockHash());
DisconnectResult res = chainstate.DisconnectBlock(block, pindex, coins);
if (res == DISCONNECT_FAILED) {
return error("VerifyDB(): *** irrecoverable inconsistency in block data at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
}
if (res == DISCONNECT_UNCLEAN) {
nGoodTransactions = 0;
pindexFailure = pindex;
} else {
nGoodTransactions += block.vtx.size();
}
}
if (ShutdownRequested()) return true;
}
if (pindexFailure) {
return error("VerifyDB(): *** coin database inconsistencies found (last %i blocks, %i good transactions before that)\n", chainstate.m_chain.Height() - pindexFailure->nHeight + 1, nGoodTransactions);
}
// store block count as we move pindex at check level >= 4
int block_count = chainstate.m_chain.Height() - pindex->nHeight;
// check level 4: try reconnecting blocks
if (nCheckLevel >= 4) {
while (pindex != chainstate.m_chain.Tip()) {
const int percentageDone = std::max(1, std::min(99, 100 - (int)(((double)(chainstate.m_chain.Height() - pindex->nHeight)) / (double)nCheckDepth * 50)));
if (reportDone < percentageDone / 10) {
// report every 10% step
LogPrintf("[%d%%]...", percentageDone); /* Continued */
reportDone = percentageDone / 10;
}
uiInterface.ShowProgress(_("Verifying blocks…").translated, percentageDone, false);
pindex = chainstate.m_chain.Next(pindex);
CBlock block;
if (!ReadBlockFromDisk(block, pindex, consensus_params))
return error("VerifyDB(): *** ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
if (!chainstate.ConnectBlock(block, state, pindex, coins)) {
return error("VerifyDB(): *** found unconnectable block at %d, hash=%s (%s)", pindex->nHeight, pindex->GetBlockHash().ToString(), state.ToString());
}
if (ShutdownRequested()) return true;
}
}
LogPrintf("[DONE].\n");
LogPrintf("No coin database inconsistencies in last %i blocks (%i transactions)\n", block_count, nGoodTransactions);
return true;
}
/** Apply the effects of a block on the utxo cache, ignoring that it may already have been applied. */
bool CChainState::RollforwardBlock(const CBlockIndex* pindex, CCoinsViewCache& inputs)
{
AssertLockHeld(cs_main);
// TODO: merge with ConnectBlock
CBlock block;
if (!ReadBlockFromDisk(block, pindex, m_params.GetConsensus())) {
return error("ReplayBlock(): ReadBlockFromDisk failed at %d, hash=%s", pindex->nHeight, pindex->GetBlockHash().ToString());
}
for (const CTransactionRef& tx : block.vtx) {
if (!tx->IsCoinBase()) {
for (const CTxIn &txin : tx->vin) {
inputs.SpendCoin(txin.prevout);
}
}
// Pass check = true as every addition may be an overwrite.
AddCoins(inputs, *tx, pindex->nHeight, true);
}
return true;
}
bool CChainState::ReplayBlocks()
{
LOCK(cs_main);
CCoinsView& db = this->CoinsDB();
CCoinsViewCache cache(&db);
std::vector<uint256> hashHeads = db.GetHeadBlocks();
if (hashHeads.empty()) return true; // We're already in a consistent state.
if (hashHeads.size() != 2) return error("ReplayBlocks(): unknown inconsistent state");
uiInterface.ShowProgress(_("Replaying blocks…").translated, 0, false);
LogPrintf("Replaying blocks\n");
const CBlockIndex* pindexOld = nullptr; // Old tip during the interrupted flush.
const CBlockIndex* pindexNew; // New tip during the interrupted flush.
const CBlockIndex* pindexFork = nullptr; // Latest block common to both the old and the new tip.
if (m_blockman.m_block_index.count(hashHeads[0]) == 0) {
return error("ReplayBlocks(): reorganization to unknown block requested");
}
pindexNew = &(m_blockman.m_block_index[hashHeads[0]]);
if (!hashHeads[1].IsNull()) { // The old tip is allowed to be 0, indicating it's the first flush.
if (m_blockman.m_block_index.count(hashHeads[1]) == 0) {
return error("ReplayBlocks(): reorganization from unknown block requested");
}
pindexOld = &(m_blockman.m_block_index[hashHeads[1]]);
pindexFork = LastCommonAncestor(pindexOld, pindexNew);
assert(pindexFork != nullptr);
}
// Rollback along the old branch.
while (pindexOld != pindexFork) {
if (pindexOld->nHeight > 0) { // Never disconnect the genesis block.
CBlock block;
if (!ReadBlockFromDisk(block, pindexOld, m_params.GetConsensus())) {
return error("RollbackBlock(): ReadBlockFromDisk() failed at %d, hash=%s", pindexOld->nHeight, pindexOld->GetBlockHash().ToString());
}
LogPrintf("Rolling back %s (%i)\n", pindexOld->GetBlockHash().ToString(), pindexOld->nHeight);
DisconnectResult res = DisconnectBlock(block, pindexOld, cache);
if (res == DISCONNECT_FAILED) {
return error("RollbackBlock(): DisconnectBlock failed at %d, hash=%s", pindexOld->nHeight, pindexOld->GetBlockHash().ToString());
}
// If DISCONNECT_UNCLEAN is returned, it means a non-existing UTXO was deleted, or an existing UTXO was
// overwritten. It corresponds to cases where the block-to-be-disconnect never had all its operations
// applied to the UTXO set. However, as both writing a UTXO and deleting a UTXO are idempotent operations,
// the result is still a version of the UTXO set with the effects of that block undone.
}
pindexOld = pindexOld->pprev;
}
// Roll forward from the forking point to the new tip.
int nForkHeight = pindexFork ? pindexFork->nHeight : 0;
for (int nHeight = nForkHeight + 1; nHeight <= pindexNew->nHeight; ++nHeight) {
const CBlockIndex& pindex{*Assert(pindexNew->GetAncestor(nHeight))};
LogPrintf("Rolling forward %s (%i)\n", pindex.GetBlockHash().ToString(), nHeight);
uiInterface.ShowProgress(_("Replaying blocks…").translated, (int) ((nHeight - nForkHeight) * 100.0 / (pindexNew->nHeight - nForkHeight)) , false);
if (!RollforwardBlock(&pindex, cache)) return false;
}
cache.SetBestBlock(pindexNew->GetBlockHash());
cache.Flush();
uiInterface.ShowProgress("", 100, false);
return true;
}
bool CChainState::NeedsRedownload() const
{
AssertLockHeld(cs_main);
// At and above m_params.SegwitHeight, segwit consensus rules must be validated
CBlockIndex* block{m_chain.Tip()};
while (block != nullptr && DeploymentActiveAt(*block, m_chainman, Consensus::DEPLOYMENT_SEGWIT)) {
if (!(block->nStatus & BLOCK_OPT_WITNESS)) {
// block is insufficiently validated for a segwit client
return true;
}
block = block->pprev;
}
return false;
}
void CChainState::UnloadBlockIndex()
{
AssertLockHeld(::cs_main);
nBlockSequenceId = 1;
setBlockIndexCandidates.clear();
}
bool ChainstateManager::LoadBlockIndex()
{
AssertLockHeld(cs_main);
// Load block index from databases
bool needs_init = fReindex;
if (!fReindex) {
bool ret = m_blockman.LoadBlockIndexDB(GetConsensus());
if (!ret) return false;
std::vector<CBlockIndex*> vSortedByHeight{m_blockman.GetAllBlockIndices()};
std::sort(vSortedByHeight.begin(), vSortedByHeight.end(),
CBlockIndexHeightOnlyComparator());
// Find start of assumed-valid region.
int first_assumed_valid_height = std::numeric_limits<int>::max();
for (const CBlockIndex* block : vSortedByHeight) {
if (block->IsAssumedValid()) {
auto chainstates = GetAll();
// If we encounter an assumed-valid block index entry, ensure that we have
// one chainstate that tolerates assumed-valid entries and another that does
// not (i.e. the background validation chainstate), since assumed-valid
// entries should always be pending validation by a fully-validated chainstate.
auto any_chain = [&](auto fnc) { return std::any_of(chainstates.cbegin(), chainstates.cend(), fnc); };
assert(any_chain([](auto chainstate) { return chainstate->reliesOnAssumedValid(); }));
assert(any_chain([](auto chainstate) { return !chainstate->reliesOnAssumedValid(); }));
first_assumed_valid_height = block->nHeight;
break;
}
}
for (CBlockIndex* pindex : vSortedByHeight) {
if (ShutdownRequested()) return false;
if (pindex->IsAssumedValid() ||
(pindex->IsValid(BLOCK_VALID_TRANSACTIONS) &&
(pindex->HaveTxsDownloaded() || pindex->pprev == nullptr))) {
// Fill each chainstate's block candidate set. Only add assumed-valid
// blocks to the tip candidate set if the chainstate is allowed to rely on
// assumed-valid blocks.
//
// If all setBlockIndexCandidates contained the assumed-valid blocks, the
// background chainstate's ActivateBestChain() call would add assumed-valid
// blocks to the chain (based on how FindMostWorkChain() works). Obviously
// we don't want this since the purpose of the background validation chain
// is to validate assued-valid blocks.
//
// Note: This is considering all blocks whose height is greater or equal to
// the first assumed-valid block to be assumed-valid blocks, and excluding
// them from the background chainstate's setBlockIndexCandidates set. This
// does mean that some blocks which are not technically assumed-valid
// (later blocks on a fork beginning before the first assumed-valid block)
// might not get added to the background chainstate, but this is ok,
// because they will still be attached to the active chainstate if they
// actually contain more work.
//
// Instead of this height-based approach, an earlier attempt was made at
// detecting "holistically" whether the block index under consideration
// relied on an assumed-valid ancestor, but this proved to be too slow to
// be practical.
for (CChainState* chainstate : GetAll()) {
if (chainstate->reliesOnAssumedValid() ||
pindex->nHeight < first_assumed_valid_height) {
chainstate->setBlockIndexCandidates.insert(pindex);
}
}
}
if (pindex->nStatus & BLOCK_FAILED_MASK && (!m_best_invalid || pindex->nChainWork > m_best_invalid->nChainWork)) {
m_best_invalid = pindex;
}
if (pindex->IsValid(BLOCK_VALID_TREE) && (m_best_header == nullptr || CBlockIndexWorkComparator()(m_best_header, pindex)))
m_best_header = pindex;
}
needs_init = m_blockman.m_block_index.empty();
}
if (needs_init) {
// Everything here is for *new* reindex/DBs. Thus, though
// LoadBlockIndexDB may have set fReindex if we shut down
// mid-reindex previously, we don't check fReindex and
// instead only check it prior to LoadBlockIndexDB to set
// needs_init.
LogPrintf("Initializing databases...\n");
}
return true;
}
bool CChainState::LoadGenesisBlock()
{
LOCK(cs_main);
// Check whether we're already initialized by checking for genesis in
// m_blockman.m_block_index. Note that we can't use m_chain here, since it is
// set based on the coins db, not the block index db, which is the only
// thing loaded at this point.
if (m_blockman.m_block_index.count(m_params.GenesisBlock().GetHash()))
return true;
try {
const CBlock& block = m_params.GenesisBlock();
FlatFilePos blockPos{m_blockman.SaveBlockToDisk(block, 0, m_chain, m_params, nullptr)};
if (blockPos.IsNull()) {
return error("%s: writing genesis block to disk failed", __func__);
}
CBlockIndex* pindex = m_blockman.AddToBlockIndex(block, m_chainman.m_best_header);
ReceivedBlockTransactions(block, pindex, blockPos);
} catch (const std::runtime_error& e) {
return error("%s: failed to write genesis block: %s", __func__, e.what());
}
return true;
}
void CChainState::LoadExternalBlockFile(FILE* fileIn, FlatFilePos* dbp)
{
AssertLockNotHeld(m_chainstate_mutex);
// Map of disk positions for blocks with unknown parent (only used for reindex)
static std::multimap<uint256, FlatFilePos> mapBlocksUnknownParent;
int64_t nStart = GetTimeMillis();
int nLoaded = 0;
try {
// This takes over fileIn and calls fclose() on it in the CBufferedFile destructor
CBufferedFile blkdat(fileIn, 2*MAX_BLOCK_SERIALIZED_SIZE, MAX_BLOCK_SERIALIZED_SIZE+8, SER_DISK, CLIENT_VERSION);
uint64_t nRewind = blkdat.GetPos();
while (!blkdat.eof()) {
if (ShutdownRequested()) return;
blkdat.SetPos(nRewind);
nRewind++; // start one byte further next time, in case of failure
blkdat.SetLimit(); // remove former limit
unsigned int nSize = 0;
try {
// locate a header
unsigned char buf[CMessageHeader::MESSAGE_START_SIZE];
blkdat.FindByte(m_params.MessageStart()[0]);
nRewind = blkdat.GetPos() + 1;
blkdat >> buf;
if (memcmp(buf, m_params.MessageStart(), CMessageHeader::MESSAGE_START_SIZE)) {
continue;
}
// read size
blkdat >> nSize;
if (nSize < 80 || nSize > MAX_BLOCK_SERIALIZED_SIZE)
continue;
} catch (const std::exception&) {
// no valid block header found; don't complain
break;
}
try {
// read block
uint64_t nBlockPos = blkdat.GetPos();
if (dbp)
dbp->nPos = nBlockPos;
blkdat.SetLimit(nBlockPos + nSize);
std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>();
CBlock& block = *pblock;
blkdat >> block;
nRewind = blkdat.GetPos();
uint256 hash = block.GetHash();
{
LOCK(cs_main);
// detect out of order blocks, and store them for later
if (hash != m_params.GetConsensus().hashGenesisBlock && !m_blockman.LookupBlockIndex(block.hashPrevBlock)) {
LogPrint(BCLog::REINDEX, "%s: Out of order block %s, parent %s not known\n", __func__, hash.ToString(),
block.hashPrevBlock.ToString());
if (dbp)
mapBlocksUnknownParent.insert(std::make_pair(block.hashPrevBlock, *dbp));
continue;
}
// process in case the block isn't known yet
const CBlockIndex* pindex = m_blockman.LookupBlockIndex(hash);
if (!pindex || (pindex->nStatus & BLOCK_HAVE_DATA) == 0) {
BlockValidationState state;
if (AcceptBlock(pblock, state, nullptr, true, dbp, nullptr)) {
nLoaded++;
}
if (state.IsError()) {
break;
}
} else if (hash != m_params.GetConsensus().hashGenesisBlock && pindex->nHeight % 1000 == 0) {
LogPrint(BCLog::REINDEX, "Block Import: already had block %s at height %d\n", hash.ToString(), pindex->nHeight);
}
}
// Activate the genesis block so normal node progress can continue
if (hash == m_params.GetConsensus().hashGenesisBlock) {
BlockValidationState state;
if (!ActivateBestChain(state, nullptr)) {
break;
}
}
NotifyHeaderTip(*this);
// Recursively process earlier encountered successors of this block
std::deque<uint256> queue;
queue.push_back(hash);
while (!queue.empty()) {
uint256 head = queue.front();
queue.pop_front();
std::pair<std::multimap<uint256, FlatFilePos>::iterator, std::multimap<uint256, FlatFilePos>::iterator> range = mapBlocksUnknownParent.equal_range(head);
while (range.first != range.second) {
std::multimap<uint256, FlatFilePos>::iterator it = range.first;
std::shared_ptr<CBlock> pblockrecursive = std::make_shared<CBlock>();
if (ReadBlockFromDisk(*pblockrecursive, it->second, m_params.GetConsensus())) {
LogPrint(BCLog::REINDEX, "%s: Processing out of order child %s of %s\n", __func__, pblockrecursive->GetHash().ToString(),
head.ToString());
LOCK(cs_main);
BlockValidationState dummy;
if (AcceptBlock(pblockrecursive, dummy, nullptr, true, &it->second, nullptr)) {
nLoaded++;
queue.push_back(pblockrecursive->GetHash());
}
}
range.first++;
mapBlocksUnknownParent.erase(it);
NotifyHeaderTip(*this);
}
}
} catch (const std::exception& e) {
LogPrintf("%s: Deserialize or I/O error - %s\n", __func__, e.what());
}
}
} catch (const std::runtime_error& e) {
AbortNode(std::string("System error: ") + e.what());
}
LogPrintf("Loaded %i blocks from external file in %dms\n", nLoaded, GetTimeMillis() - nStart);
}
void CChainState::CheckBlockIndex()
{
if (!fCheckBlockIndex) {
return;
}
LOCK(cs_main);
// During a reindex, we read the genesis block and call CheckBlockIndex before ActivateBestChain,
// so we have the genesis block in m_blockman.m_block_index but no active chain. (A few of the
// tests when iterating the block tree require that m_chain has been initialized.)
if (m_chain.Height() < 0) {
assert(m_blockman.m_block_index.size() <= 1);
return;
}
// Build forward-pointing map of the entire block tree.
std::multimap<CBlockIndex*,CBlockIndex*> forward;
for (auto& [_, block_index] : m_blockman.m_block_index) {
forward.emplace(block_index.pprev, &block_index);
}
assert(forward.size() == m_blockman.m_block_index.size());
std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangeGenesis = forward.equal_range(nullptr);
CBlockIndex *pindex = rangeGenesis.first->second;
rangeGenesis.first++;
assert(rangeGenesis.first == rangeGenesis.second); // There is only one index entry with parent nullptr.
// Iterate over the entire block tree, using depth-first search.
// Along the way, remember whether there are blocks on the path from genesis
// block being explored which are the first to have certain properties.
size_t nNodes = 0;
int nHeight = 0;
CBlockIndex* pindexFirstInvalid = nullptr; // Oldest ancestor of pindex which is invalid.
CBlockIndex* pindexFirstMissing = nullptr; // Oldest ancestor of pindex which does not have BLOCK_HAVE_DATA.
CBlockIndex* pindexFirstNeverProcessed = nullptr; // Oldest ancestor of pindex for which nTx == 0.
CBlockIndex* pindexFirstNotTreeValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_TREE (regardless of being valid or not).
CBlockIndex* pindexFirstNotTransactionsValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_TRANSACTIONS (regardless of being valid or not).
CBlockIndex* pindexFirstNotChainValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_CHAIN (regardless of being valid or not).
CBlockIndex* pindexFirstNotScriptsValid = nullptr; // Oldest ancestor of pindex which does not have BLOCK_VALID_SCRIPTS (regardless of being valid or not).
while (pindex != nullptr) {
nNodes++;
if (pindexFirstInvalid == nullptr && pindex->nStatus & BLOCK_FAILED_VALID) pindexFirstInvalid = pindex;
// Assumed-valid index entries will not have data since we haven't downloaded the
// full block yet.
if (pindexFirstMissing == nullptr && !(pindex->nStatus & BLOCK_HAVE_DATA) && !pindex->IsAssumedValid()) {
pindexFirstMissing = pindex;
}
if (pindexFirstNeverProcessed == nullptr && pindex->nTx == 0) pindexFirstNeverProcessed = pindex;
if (pindex->pprev != nullptr && pindexFirstNotTreeValid == nullptr && (pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TREE) pindexFirstNotTreeValid = pindex;
if (pindex->pprev != nullptr && !pindex->IsAssumedValid()) {
// Skip validity flag checks for BLOCK_ASSUMED_VALID index entries, since these
// *_VALID_MASK flags will not be present for index entries we are temporarily assuming
// valid.
if (pindexFirstNotTransactionsValid == nullptr &&
(pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_TRANSACTIONS) {
pindexFirstNotTransactionsValid = pindex;
}
if (pindexFirstNotChainValid == nullptr &&
(pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_CHAIN) {
pindexFirstNotChainValid = pindex;
}
if (pindexFirstNotScriptsValid == nullptr &&
(pindex->nStatus & BLOCK_VALID_MASK) < BLOCK_VALID_SCRIPTS) {
pindexFirstNotScriptsValid = pindex;
}
}
// Begin: actual consistency checks.
if (pindex->pprev == nullptr) {
// Genesis block checks.
assert(pindex->GetBlockHash() == m_params.GetConsensus().hashGenesisBlock); // Genesis block's hash must match.
assert(pindex == m_chain.Genesis()); // The current active chain's genesis block must be this block.
}
if (!pindex->HaveTxsDownloaded()) assert(pindex->nSequenceId <= 0); // nSequenceId can't be set positive for blocks that aren't linked (negative is used for preciousblock)
// VALID_TRANSACTIONS is equivalent to nTx > 0 for all nodes (whether or not pruning has occurred).
// HAVE_DATA is only equivalent to nTx > 0 (or VALID_TRANSACTIONS) if no pruning has occurred.
// Unless these indexes are assumed valid and pending block download on a
// background chainstate.
if (!m_blockman.m_have_pruned && !pindex->IsAssumedValid()) {
// If we've never pruned, then HAVE_DATA should be equivalent to nTx > 0
assert(!(pindex->nStatus & BLOCK_HAVE_DATA) == (pindex->nTx == 0));
assert(pindexFirstMissing == pindexFirstNeverProcessed);
} else {
// If we have pruned, then we can only say that HAVE_DATA implies nTx > 0
if (pindex->nStatus & BLOCK_HAVE_DATA) assert(pindex->nTx > 0);
}
if (pindex->nStatus & BLOCK_HAVE_UNDO) assert(pindex->nStatus & BLOCK_HAVE_DATA);
if (pindex->IsAssumedValid()) {
// Assumed-valid blocks should have some nTx value.
assert(pindex->nTx > 0);
// Assumed-valid blocks should connect to the main chain.
assert((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TREE);
} else {
// Otherwise there should only be an nTx value if we have
// actually seen a block's transactions.
assert(((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TRANSACTIONS) == (pindex->nTx > 0)); // This is pruning-independent.
}
// All parents having had data (at some point) is equivalent to all parents being VALID_TRANSACTIONS, which is equivalent to HaveTxsDownloaded().
assert((pindexFirstNeverProcessed == nullptr) == pindex->HaveTxsDownloaded());
assert((pindexFirstNotTransactionsValid == nullptr) == pindex->HaveTxsDownloaded());
assert(pindex->nHeight == nHeight); // nHeight must be consistent.
assert(pindex->pprev == nullptr || pindex->nChainWork >= pindex->pprev->nChainWork); // For every block except the genesis block, the chainwork must be larger than the parent's.
assert(nHeight < 2 || (pindex->pskip && (pindex->pskip->nHeight < nHeight))); // The pskip pointer must point back for all but the first 2 blocks.
assert(pindexFirstNotTreeValid == nullptr); // All m_blockman.m_block_index entries must at least be TREE valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_TREE) assert(pindexFirstNotTreeValid == nullptr); // TREE valid implies all parents are TREE valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_CHAIN) assert(pindexFirstNotChainValid == nullptr); // CHAIN valid implies all parents are CHAIN valid
if ((pindex->nStatus & BLOCK_VALID_MASK) >= BLOCK_VALID_SCRIPTS) assert(pindexFirstNotScriptsValid == nullptr); // SCRIPTS valid implies all parents are SCRIPTS valid
if (pindexFirstInvalid == nullptr) {
// Checks for not-invalid blocks.
assert((pindex->nStatus & BLOCK_FAILED_MASK) == 0); // The failed mask cannot be set for blocks without invalid parents.
}
if (!CBlockIndexWorkComparator()(pindex, m_chain.Tip()) && pindexFirstNeverProcessed == nullptr) {
if (pindexFirstInvalid == nullptr) {
const bool is_active = this == &m_chainman.ActiveChainstate();
// If this block sorts at least as good as the current tip and
// is valid and we have all data for its parents, it must be in
// setBlockIndexCandidates. m_chain.Tip() must also be there
// even if some data has been pruned.
//
// Don't perform this check for the background chainstate since
// its setBlockIndexCandidates shouldn't have some entries (i.e. those past the
// snapshot block) which do exist in the block index for the active chainstate.
if (is_active && (pindexFirstMissing == nullptr || pindex == m_chain.Tip())) {
assert(setBlockIndexCandidates.count(pindex));
}
// If some parent is missing, then it could be that this block was in
// setBlockIndexCandidates but had to be removed because of the missing data.
// In this case it must be in m_blocks_unlinked -- see test below.
}
} else { // If this block sorts worse than the current tip or some ancestor's block has never been seen, it cannot be in setBlockIndexCandidates.
assert(setBlockIndexCandidates.count(pindex) == 0);
}
// Check whether this block is in m_blocks_unlinked.
std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangeUnlinked = m_blockman.m_blocks_unlinked.equal_range(pindex->pprev);
bool foundInUnlinked = false;
while (rangeUnlinked.first != rangeUnlinked.second) {
assert(rangeUnlinked.first->first == pindex->pprev);
if (rangeUnlinked.first->second == pindex) {
foundInUnlinked = true;
break;
}
rangeUnlinked.first++;
}
if (pindex->pprev && (pindex->nStatus & BLOCK_HAVE_DATA) && pindexFirstNeverProcessed != nullptr && pindexFirstInvalid == nullptr) {
// If this block has block data available, some parent was never received, and has no invalid parents, it must be in m_blocks_unlinked.
assert(foundInUnlinked);
}
if (!(pindex->nStatus & BLOCK_HAVE_DATA)) assert(!foundInUnlinked); // Can't be in m_blocks_unlinked if we don't HAVE_DATA
if (pindexFirstMissing == nullptr) assert(!foundInUnlinked); // We aren't missing data for any parent -- cannot be in m_blocks_unlinked.
if (pindex->pprev && (pindex->nStatus & BLOCK_HAVE_DATA) && pindexFirstNeverProcessed == nullptr && pindexFirstMissing != nullptr) {
// We HAVE_DATA for this block, have received data for all parents at some point, but we're currently missing data for some parent.
assert(m_blockman.m_have_pruned); // We must have pruned.
// This block may have entered m_blocks_unlinked if:
// - it has a descendant that at some point had more work than the
// tip, and
// - we tried switching to that descendant but were missing
// data for some intermediate block between m_chain and the
// tip.
// So if this block is itself better than m_chain.Tip() and it wasn't in
// setBlockIndexCandidates, then it must be in m_blocks_unlinked.
if (!CBlockIndexWorkComparator()(pindex, m_chain.Tip()) && setBlockIndexCandidates.count(pindex) == 0) {
if (pindexFirstInvalid == nullptr) {
assert(foundInUnlinked);
}
}
}
// assert(pindex->GetBlockHash() == pindex->GetBlockHeader().GetHash()); // Perhaps too slow
// End: actual consistency checks.
// Try descending into the first subnode.
std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> range = forward.equal_range(pindex);
if (range.first != range.second) {
// A subnode was found.
pindex = range.first->second;
nHeight++;
continue;
}
// This is a leaf node.
// Move upwards until we reach a node of which we have not yet visited the last child.
while (pindex) {
// We are going to either move to a parent or a sibling of pindex.
// If pindex was the first with a certain property, unset the corresponding variable.
if (pindex == pindexFirstInvalid) pindexFirstInvalid = nullptr;
if (pindex == pindexFirstMissing) pindexFirstMissing = nullptr;
if (pindex == pindexFirstNeverProcessed) pindexFirstNeverProcessed = nullptr;
if (pindex == pindexFirstNotTreeValid) pindexFirstNotTreeValid = nullptr;
if (pindex == pindexFirstNotTransactionsValid) pindexFirstNotTransactionsValid = nullptr;
if (pindex == pindexFirstNotChainValid) pindexFirstNotChainValid = nullptr;
if (pindex == pindexFirstNotScriptsValid) pindexFirstNotScriptsValid = nullptr;
// Find our parent.
CBlockIndex* pindexPar = pindex->pprev;
// Find which child we just visited.
std::pair<std::multimap<CBlockIndex*,CBlockIndex*>::iterator,std::multimap<CBlockIndex*,CBlockIndex*>::iterator> rangePar = forward.equal_range(pindexPar);
while (rangePar.first->second != pindex) {
assert(rangePar.first != rangePar.second); // Our parent must have at least the node we're coming from as child.
rangePar.first++;
}
// Proceed to the next one.
rangePar.first++;
if (rangePar.first != rangePar.second) {
// Move to the sibling.
pindex = rangePar.first->second;
break;
} else {
// Move up further.
pindex = pindexPar;
nHeight--;
continue;
}
}
}
// Check that we actually traversed the entire map.
assert(nNodes == forward.size());
}
std::string CChainState::ToString()
{
AssertLockHeld(::cs_main);
CBlockIndex* tip = m_chain.Tip();
return strprintf("Chainstate [%s] @ height %d (%s)",
m_from_snapshot_blockhash ? "snapshot" : "ibd",
tip ? tip->nHeight : -1, tip ? tip->GetBlockHash().ToString() : "null");
}
bool CChainState::ResizeCoinsCaches(size_t coinstip_size, size_t coinsdb_size)
{
AssertLockHeld(::cs_main);
if (coinstip_size == m_coinstip_cache_size_bytes &&
coinsdb_size == m_coinsdb_cache_size_bytes) {
// Cache sizes are unchanged, no need to continue.
return true;
}
size_t old_coinstip_size = m_coinstip_cache_size_bytes;
m_coinstip_cache_size_bytes = coinstip_size;
m_coinsdb_cache_size_bytes = coinsdb_size;
CoinsDB().ResizeCache(coinsdb_size);
LogPrintf("[%s] resized coinsdb cache to %.1f MiB\n",
this->ToString(), coinsdb_size * (1.0 / 1024 / 1024));
LogPrintf("[%s] resized coinstip cache to %.1f MiB\n",
this->ToString(), coinstip_size * (1.0 / 1024 / 1024));
BlockValidationState state;
bool ret;
if (coinstip_size > old_coinstip_size) {
// Likely no need to flush if cache sizes have grown.
ret = FlushStateToDisk(state, FlushStateMode::IF_NEEDED);
} else {
// Otherwise, flush state to disk and deallocate the in-memory coins map.
ret = FlushStateToDisk(state, FlushStateMode::ALWAYS);
CoinsTip().ReallocateCache();
}
return ret;
}
static const uint64_t MEMPOOL_DUMP_VERSION = 1;
bool LoadMempool(CTxMemPool& pool, CChainState& active_chainstate, FopenFn mockable_fopen_function)
{
int64_t nExpiryTimeout = gArgs.GetIntArg("-mempoolexpiry", DEFAULT_MEMPOOL_EXPIRY) * 60 * 60;
FILE* filestr{mockable_fopen_function(gArgs.GetDataDirNet() / "mempool.dat", "rb")};
CAutoFile file(filestr, SER_DISK, CLIENT_VERSION);
if (file.IsNull()) {
LogPrintf("Failed to open mempool file from disk. Continuing anyway.\n");
return false;
}
int64_t count = 0;
int64_t expired = 0;
int64_t failed = 0;
int64_t already_there = 0;
int64_t unbroadcast = 0;
int64_t nNow = GetTime();
try {
uint64_t version;
file >> version;
if (version != MEMPOOL_DUMP_VERSION) {
return false;
}
uint64_t num;
file >> num;
while (num) {
--num;
CTransactionRef tx;
int64_t nTime;
int64_t nFeeDelta;
file >> tx;
file >> nTime;
file >> nFeeDelta;
CAmount amountdelta = nFeeDelta;
if (amountdelta) {
pool.PrioritiseTransaction(tx->GetHash(), amountdelta);
}
if (nTime > nNow - nExpiryTimeout) {
LOCK(cs_main);
const auto& accepted = AcceptToMemoryPool(active_chainstate, tx, nTime, /*bypass_limits=*/false, /*test_accept=*/false);
if (accepted.m_result_type == MempoolAcceptResult::ResultType::VALID) {
++count;
} else {
// mempool may contain the transaction already, e.g. from
// wallet(s) having loaded it while we were processing
// mempool transactions; consider these as valid, instead of
// failed, but mark them as 'already there'
if (pool.exists(GenTxid::Txid(tx->GetHash()))) {
++already_there;
} else {
++failed;
}
}
} else {
++expired;
}
if (ShutdownRequested())
return false;
}
std::map<uint256, CAmount> mapDeltas;
file >> mapDeltas;
for (const auto& i : mapDeltas) {
pool.PrioritiseTransaction(i.first, i.second);
}
std::set<uint256> unbroadcast_txids;
file >> unbroadcast_txids;
unbroadcast = unbroadcast_txids.size();
for (const auto& txid : unbroadcast_txids) {
// Ensure transactions were accepted to mempool then add to
// unbroadcast set.
if (pool.get(txid) != nullptr) pool.AddUnbroadcastTx(txid);
}
} catch (const std::exception& e) {
LogPrintf("Failed to deserialize mempool data on disk: %s. Continuing anyway.\n", e.what());
return false;
}
LogPrintf("Imported mempool transactions from disk: %i succeeded, %i failed, %i expired, %i already there, %i waiting for initial broadcast\n", count, failed, expired, already_there, unbroadcast);
return true;
}
bool DumpMempool(const CTxMemPool& pool, FopenFn mockable_fopen_function, bool skip_file_commit)
{
int64_t start = GetTimeMicros();
std::map<uint256, CAmount> mapDeltas;
std::vector<TxMempoolInfo> vinfo;
std::set<uint256> unbroadcast_txids;
static Mutex dump_mutex;
LOCK(dump_mutex);
{
LOCK(pool.cs);
for (const auto &i : pool.mapDeltas) {
mapDeltas[i.first] = i.second;
}
vinfo = pool.infoAll();
unbroadcast_txids = pool.GetUnbroadcastTxs();
}
int64_t mid = GetTimeMicros();
try {
FILE* filestr{mockable_fopen_function(gArgs.GetDataDirNet() / "mempool.dat.new", "wb")};
if (!filestr) {
return false;
}
CAutoFile file(filestr, SER_DISK, CLIENT_VERSION);
uint64_t version = MEMPOOL_DUMP_VERSION;
file << version;
file << (uint64_t)vinfo.size();
for (const auto& i : vinfo) {
file << *(i.tx);
file << int64_t{count_seconds(i.m_time)};
file << int64_t{i.nFeeDelta};
mapDeltas.erase(i.tx->GetHash());
}
file << mapDeltas;
LogPrintf("Writing %d unbroadcast transactions to disk.\n", unbroadcast_txids.size());
file << unbroadcast_txids;
if (!skip_file_commit && !FileCommit(file.Get()))
throw std::runtime_error("FileCommit failed");
file.fclose();
if (!RenameOver(gArgs.GetDataDirNet() / "mempool.dat.new", gArgs.GetDataDirNet() / "mempool.dat")) {
throw std::runtime_error("Rename failed");
}
int64_t last = GetTimeMicros();
LogPrintf("Dumped mempool: %gs to copy, %gs to dump\n", (mid-start)*MICRO, (last-mid)*MICRO);
} catch (const std::exception& e) {
LogPrintf("Failed to dump mempool: %s. Continuing anyway.\n", e.what());
return false;
}
return true;
}
//! Guess how far we are in the verification process at the given block index
//! require cs_main if pindex has not been validated yet (because nChainTx might be unset)
double GuessVerificationProgress(const ChainTxData& data, const CBlockIndex *pindex) {
if (pindex == nullptr)
return 0.0;
int64_t nNow = time(nullptr);
double fTxTotal;
if (pindex->nChainTx <= data.nTxCount) {
fTxTotal = data.nTxCount + (nNow - data.nTime) * data.dTxRate;
} else {
fTxTotal = pindex->nChainTx + (nNow - pindex->GetBlockTime()) * data.dTxRate;
}
return std::min<double>(pindex->nChainTx / fTxTotal, 1.0);
}
std::optional<uint256> ChainstateManager::SnapshotBlockhash() const
{
LOCK(::cs_main);
if (m_active_chainstate && m_active_chainstate->m_from_snapshot_blockhash) {
// If a snapshot chainstate exists, it will always be our active.
return m_active_chainstate->m_from_snapshot_blockhash;
}
return std::nullopt;
}
std::vector<CChainState*> ChainstateManager::GetAll()
{
LOCK(::cs_main);
std::vector<CChainState*> out;
if (!IsSnapshotValidated() && m_ibd_chainstate) {
out.push_back(m_ibd_chainstate.get());
}
if (m_snapshot_chainstate) {
out.push_back(m_snapshot_chainstate.get());
}
return out;
}
CChainState& ChainstateManager::InitializeChainstate(
CTxMemPool* mempool, const std::optional<uint256>& snapshot_blockhash)
{
AssertLockHeld(::cs_main);
bool is_snapshot = snapshot_blockhash.has_value();
std::unique_ptr<CChainState>& to_modify =
is_snapshot ? m_snapshot_chainstate : m_ibd_chainstate;
if (to_modify) {
throw std::logic_error("should not be overwriting a chainstate");
}
to_modify.reset(new CChainState(mempool, m_blockman, *this, snapshot_blockhash));
// Snapshot chainstates and initial IBD chaintates always become active.
if (is_snapshot || (!is_snapshot && !m_active_chainstate)) {
LogPrintf("Switching active chainstate to %s\n", to_modify->ToString());
m_active_chainstate = to_modify.get();
} else {
throw std::logic_error("unexpected chainstate activation");
}
return *to_modify;
}
const AssumeutxoData* ExpectedAssumeutxo(
const int height, const CChainParams& chainparams)
{
const MapAssumeutxo& valid_assumeutxos_map = chainparams.Assumeutxo();
const auto assumeutxo_found = valid_assumeutxos_map.find(height);
if (assumeutxo_found != valid_assumeutxos_map.end()) {
return &assumeutxo_found->second;
}
return nullptr;
}
bool ChainstateManager::ActivateSnapshot(
CAutoFile& coins_file,
const SnapshotMetadata& metadata,
bool in_memory)
{
uint256 base_blockhash = metadata.m_base_blockhash;
if (this->SnapshotBlockhash()) {
LogPrintf("[snapshot] can't activate a snapshot-based chainstate more than once\n");
return false;
}
int64_t current_coinsdb_cache_size{0};
int64_t current_coinstip_cache_size{0};
// Cache percentages to allocate to each chainstate.
//
// These particular percentages don't matter so much since they will only be
// relevant during snapshot activation; caches are rebalanced at the conclusion of
// this function. We want to give (essentially) all available cache capacity to the
// snapshot to aid the bulk load later in this function.
static constexpr double IBD_CACHE_PERC = 0.01;
static constexpr double SNAPSHOT_CACHE_PERC = 0.99;
{
LOCK(::cs_main);
// Resize the coins caches to ensure we're not exceeding memory limits.
//
// Allocate the majority of the cache to the incoming snapshot chainstate, since
// (optimistically) getting to its tip will be the top priority. We'll need to call
// `MaybeRebalanceCaches()` once we're done with this function to ensure
// the right allocation (including the possibility that no snapshot was activated
// and that we should restore the active chainstate caches to their original size).
//
current_coinsdb_cache_size = this->ActiveChainstate().m_coinsdb_cache_size_bytes;
current_coinstip_cache_size = this->ActiveChainstate().m_coinstip_cache_size_bytes;
// Temporarily resize the active coins cache to make room for the newly-created
// snapshot chain.
this->ActiveChainstate().ResizeCoinsCaches(
static_cast<size_t>(current_coinstip_cache_size * IBD_CACHE_PERC),
static_cast<size_t>(current_coinsdb_cache_size * IBD_CACHE_PERC));
}
auto snapshot_chainstate = WITH_LOCK(::cs_main,
return std::make_unique<CChainState>(
/*mempool=*/nullptr, m_blockman, *this, base_blockhash));
{
LOCK(::cs_main);
snapshot_chainstate->InitCoinsDB(
static_cast<size_t>(current_coinsdb_cache_size * SNAPSHOT_CACHE_PERC),
in_memory, false, "chainstate");
snapshot_chainstate->InitCoinsCache(
static_cast<size_t>(current_coinstip_cache_size * SNAPSHOT_CACHE_PERC));
}
const bool snapshot_ok = this->PopulateAndValidateSnapshot(
*snapshot_chainstate, coins_file, metadata);
if (!snapshot_ok) {
WITH_LOCK(::cs_main, this->MaybeRebalanceCaches());
return false;
}
{
LOCK(::cs_main);
assert(!m_snapshot_chainstate);
m_snapshot_chainstate.swap(snapshot_chainstate);
const bool chaintip_loaded = m_snapshot_chainstate->LoadChainTip();
assert(chaintip_loaded);
m_active_chainstate = m_snapshot_chainstate.get();
LogPrintf("[snapshot] successfully activated snapshot %s\n", base_blockhash.ToString());
LogPrintf("[snapshot] (%.2f MB)\n",
m_snapshot_chainstate->CoinsTip().DynamicMemoryUsage() / (1000 * 1000));
this->MaybeRebalanceCaches();
}
return true;
}
static void FlushSnapshotToDisk(CCoinsViewCache& coins_cache, bool snapshot_loaded)
{
LOG_TIME_MILLIS_WITH_CATEGORY_MSG_ONCE(
strprintf("%s (%.2f MB)",
snapshot_loaded ? "saving snapshot chainstate" : "flushing coins cache",
coins_cache.DynamicMemoryUsage() / (1000 * 1000)),
BCLog::LogFlags::ALL);
coins_cache.Flush();
}
bool ChainstateManager::PopulateAndValidateSnapshot(
CChainState& snapshot_chainstate,
CAutoFile& coins_file,
const SnapshotMetadata& metadata)
{
// It's okay to release cs_main before we're done using `coins_cache` because we know
// that nothing else will be referencing the newly created snapshot_chainstate yet.
CCoinsViewCache& coins_cache = *WITH_LOCK(::cs_main, return &snapshot_chainstate.CoinsTip());
uint256 base_blockhash = metadata.m_base_blockhash;
CBlockIndex* snapshot_start_block = WITH_LOCK(::cs_main, return m_blockman.LookupBlockIndex(base_blockhash));
if (!snapshot_start_block) {
// Needed for ComputeUTXOStats and ExpectedAssumeutxo to determine the
// height and to avoid a crash when base_blockhash.IsNull()
LogPrintf("[snapshot] Did not find snapshot start blockheader %s\n",
base_blockhash.ToString());
return false;
}
int base_height = snapshot_start_block->nHeight;
auto maybe_au_data = ExpectedAssumeutxo(base_height, GetParams());
if (!maybe_au_data) {
LogPrintf("[snapshot] assumeutxo height in snapshot metadata not recognized " /* Continued */
"(%d) - refusing to load snapshot\n", base_height);
return false;
}
const AssumeutxoData& au_data = *maybe_au_data;
COutPoint outpoint;
Coin coin;
const uint64_t coins_count = metadata.m_coins_count;
uint64_t coins_left = metadata.m_coins_count;
LogPrintf("[snapshot] loading coins from snapshot %s\n", base_blockhash.ToString());
int64_t coins_processed{0};
while (coins_left > 0) {
try {
coins_file >> outpoint;
coins_file >> coin;
} catch (const std::ios_base::failure&) {
LogPrintf("[snapshot] bad snapshot format or truncated snapshot after deserializing %d coins\n",
coins_count - coins_left);
return false;
}
if (coin.nHeight > base_height ||
outpoint.n >= std::numeric_limits<decltype(outpoint.n)>::max() // Avoid integer wrap-around in coinstats.cpp:ApplyHash
) {
LogPrintf("[snapshot] bad snapshot data after deserializing %d coins\n",
coins_count - coins_left);
return false;
}
coins_cache.EmplaceCoinInternalDANGER(std::move(outpoint), std::move(coin));
--coins_left;
++coins_processed;
if (coins_processed % 1000000 == 0) {
LogPrintf("[snapshot] %d coins loaded (%.2f%%, %.2f MB)\n",
coins_processed,
static_cast<float>(coins_processed) * 100 / static_cast<float>(coins_count),
coins_cache.DynamicMemoryUsage() / (1000 * 1000));
}
// Batch write and flush (if we need to) every so often.
//
// If our average Coin size is roughly 41 bytes, checking every 120,000 coins
// means <5MB of memory imprecision.
if (coins_processed % 120000 == 0) {
if (ShutdownRequested()) {
return false;
}
const auto snapshot_cache_state = WITH_LOCK(::cs_main,
return snapshot_chainstate.GetCoinsCacheSizeState());
if (snapshot_cache_state >= CoinsCacheSizeState::CRITICAL) {
// This is a hack - we don't know what the actual best block is, but that
// doesn't matter for the purposes of flushing the cache here. We'll set this
// to its correct value (`base_blockhash`) below after the coins are loaded.
coins_cache.SetBestBlock(GetRandHash());
// No need to acquire cs_main since this chainstate isn't being used yet.
FlushSnapshotToDisk(coins_cache, /*snapshot_loaded=*/false);
}
}
}
// Important that we set this. This and the coins_cache accesses above are
// sort of a layer violation, but either we reach into the innards of
// CCoinsViewCache here or we have to invert some of the CChainState to
// embed them in a snapshot-activation-specific CCoinsViewCache bulk load
// method.
coins_cache.SetBestBlock(base_blockhash);
bool out_of_coins{false};
try {
coins_file >> outpoint;
} catch (const std::ios_base::failure&) {
// We expect an exception since we should be out of coins.
out_of_coins = true;
}
if (!out_of_coins) {
LogPrintf("[snapshot] bad snapshot - coins left over after deserializing %d coins\n",
coins_count);
return false;
}
LogPrintf("[snapshot] loaded %d (%.2f MB) coins from snapshot %s\n",
coins_count,
coins_cache.DynamicMemoryUsage() / (1000 * 1000),
base_blockhash.ToString());
// No need to acquire cs_main since this chainstate isn't being used yet.
FlushSnapshotToDisk(coins_cache, /*snapshot_loaded=*/true);
assert(coins_cache.GetBestBlock() == base_blockhash);
auto breakpoint_fnc = [] { /* TODO insert breakpoint here? */ };
// As above, okay to immediately release cs_main here since no other context knows
// about the snapshot_chainstate.
CCoinsViewDB* snapshot_coinsdb = WITH_LOCK(::cs_main, return &snapshot_chainstate.CoinsDB());
const std::optional<CCoinsStats> maybe_stats = ComputeUTXOStats(CoinStatsHashType::HASH_SERIALIZED, snapshot_coinsdb, m_blockman, breakpoint_fnc);
if (!maybe_stats.has_value()) {
LogPrintf("[snapshot] failed to generate coins stats\n");
return false;
}
// Assert that the deserialized chainstate contents match the expected assumeutxo value.
if (AssumeutxoHash{maybe_stats->hashSerialized} != au_data.hash_serialized) {
LogPrintf("[snapshot] bad snapshot content hash: expected %s, got %s\n",
au_data.hash_serialized.ToString(), maybe_stats->hashSerialized.ToString());
return false;
}
snapshot_chainstate.m_chain.SetTip(snapshot_start_block);
// The remainder of this function requires modifying data protected by cs_main.
LOCK(::cs_main);
// Fake various pieces of CBlockIndex state:
CBlockIndex* index = nullptr;
// Don't make any modifications to the genesis block.
// This is especially important because we don't want to erroneously
// apply BLOCK_ASSUMED_VALID to genesis, which would happen if we didn't skip
// it here (since it apparently isn't BLOCK_VALID_SCRIPTS).
constexpr int AFTER_GENESIS_START{1};
for (int i = AFTER_GENESIS_START; i <= snapshot_chainstate.m_chain.Height(); ++i) {
index = snapshot_chainstate.m_chain[i];
// Fake nTx so that LoadBlockIndex() loads assumed-valid CBlockIndex
// entries (among other things)
if (!index->nTx) {
index->nTx = 1;
}
// Fake nChainTx so that GuessVerificationProgress reports accurately
index->nChainTx = index->pprev->nChainTx + index->nTx;
// Mark unvalidated block index entries beneath the snapshot base block as assumed-valid.
if (!index->IsValid(BLOCK_VALID_SCRIPTS)) {
// This flag will be removed once the block is fully validated by a
// background chainstate.
index->nStatus |= BLOCK_ASSUMED_VALID;
}
// Fake BLOCK_OPT_WITNESS so that CChainState::NeedsRedownload()
// won't ask to rewind the entire assumed-valid chain on startup.
if (DeploymentActiveAt(*index, *this, Consensus::DEPLOYMENT_SEGWIT)) {
index->nStatus |= BLOCK_OPT_WITNESS;
}
m_blockman.m_dirty_blockindex.insert(index);
// Changes to the block index will be flushed to disk after this call
// returns in `ActivateSnapshot()`, when `MaybeRebalanceCaches()` is
// called, since we've added a snapshot chainstate and therefore will
// have to downsize the IBD chainstate, which will result in a call to
// `FlushStateToDisk(ALWAYS)`.
}
assert(index);
index->nChainTx = au_data.nChainTx;
snapshot_chainstate.setBlockIndexCandidates.insert(snapshot_start_block);
LogPrintf("[snapshot] validated snapshot (%.2f MB)\n",
coins_cache.DynamicMemoryUsage() / (1000 * 1000));
return true;
}
CChainState& ChainstateManager::ActiveChainstate() const
{
LOCK(::cs_main);
assert(m_active_chainstate);
return *m_active_chainstate;
}
bool ChainstateManager::IsSnapshotActive() const
{
LOCK(::cs_main);
return m_snapshot_chainstate && m_active_chainstate == m_snapshot_chainstate.get();
}
void ChainstateManager::MaybeRebalanceCaches()
{
AssertLockHeld(::cs_main);
if (m_ibd_chainstate && !m_snapshot_chainstate) {
LogPrintf("[snapshot] allocating all cache to the IBD chainstate\n");
// Allocate everything to the IBD chainstate.
m_ibd_chainstate->ResizeCoinsCaches(m_total_coinstip_cache, m_total_coinsdb_cache);
}
else if (m_snapshot_chainstate && !m_ibd_chainstate) {
LogPrintf("[snapshot] allocating all cache to the snapshot chainstate\n");
// Allocate everything to the snapshot chainstate.
m_snapshot_chainstate->ResizeCoinsCaches(m_total_coinstip_cache, m_total_coinsdb_cache);
}
else if (m_ibd_chainstate && m_snapshot_chainstate) {
// If both chainstates exist, determine who needs more cache based on IBD status.
//
// Note: shrink caches first so that we don't inadvertently overwhelm available memory.
if (m_snapshot_chainstate->IsInitialBlockDownload()) {
m_ibd_chainstate->ResizeCoinsCaches(
m_total_coinstip_cache * 0.05, m_total_coinsdb_cache * 0.05);
m_snapshot_chainstate->ResizeCoinsCaches(
m_total_coinstip_cache * 0.95, m_total_coinsdb_cache * 0.95);
} else {
m_snapshot_chainstate->ResizeCoinsCaches(
m_total_coinstip_cache * 0.05, m_total_coinsdb_cache * 0.05);
m_ibd_chainstate->ResizeCoinsCaches(
m_total_coinstip_cache * 0.95, m_total_coinsdb_cache * 0.95);
}
}
}
ChainstateManager::~ChainstateManager()
{
LOCK(::cs_main);
m_versionbitscache.Clear();
// TODO: The warning cache should probably become non-global
for (auto& i : warningcache) {
i.clear();
}
}
|