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
|
// Copyright (c) 2020-2022 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 <test/fuzz/fuzz.h>
#include <primitives/transaction.h>
#include <pubkey.h>
#include <script/interpreter.h>
#include <serialize.h>
#include <streams.h>
#include <univalue.h>
#include <util/strencodings.h>
#include <util/string.h>
#include <cstdint>
#include <string>
#include <vector>
// This fuzz "test" can be used to minimize test cases for script_assets_test in
// src/test/script_tests.cpp. While it written as a fuzz test, and can be used as such,
// fuzzing the inputs is unlikely to construct useful test cases.
//
// Instead, it is primarily intended to be run on a test set that was generated
// externally, for example using test/functional/feature_taproot.py's --dumptests mode.
// The minimized set can then be concatenated together, surrounded by '[' and ']',
// and used as the script_assets_test.json input to the script_assets_test unit test:
//
// (normal build)
// $ mkdir dump
// $ for N in $(seq 1 10); do TEST_DUMP_DIR=dump test/functional/feature_taproot.py --dumptests; done
// $ ...
//
// (libFuzzer build)
// $ mkdir dump-min
// $ FUZZ=script_assets_test_minimizer ./src/test/fuzz/fuzz -merge=1 -use_value_profile=1 dump-min/ dump/
// $ (echo -en '[\n'; cat dump-min/* | head -c -2; echo -en '\n]') >script_assets_test.json
namespace {
std::vector<unsigned char> CheckedParseHex(const std::string& str)
{
if (str.size() && !IsHex(str)) throw std::runtime_error("Non-hex input '" + str + "'");
return ParseHex(str);
}
CScript ScriptFromHex(const std::string& str)
{
std::vector<unsigned char> data = CheckedParseHex(str);
return CScript(data.begin(), data.end());
}
CMutableTransaction TxFromHex(const std::string& str)
{
CMutableTransaction tx;
try {
SpanReader{SER_DISK, SERIALIZE_TRANSACTION_NO_WITNESS, CheckedParseHex(str)} >> tx;
} catch (const std::ios_base::failure&) {
throw std::runtime_error("Tx deserialization failure");
}
return tx;
}
std::vector<CTxOut> TxOutsFromJSON(const UniValue& univalue)
{
if (!univalue.isArray()) throw std::runtime_error("Prevouts must be array");
std::vector<CTxOut> prevouts;
for (size_t i = 0; i < univalue.size(); ++i) {
CTxOut txout;
try {
SpanReader{SER_DISK, 0, CheckedParseHex(univalue[i].get_str())} >> txout;
} catch (const std::ios_base::failure&) {
throw std::runtime_error("Prevout invalid format");
}
prevouts.push_back(std::move(txout));
}
return prevouts;
}
CScriptWitness ScriptWitnessFromJSON(const UniValue& univalue)
{
if (!univalue.isArray()) throw std::runtime_error("Script witness is not array");
CScriptWitness scriptwitness;
for (size_t i = 0; i < univalue.size(); ++i) {
auto bytes = CheckedParseHex(univalue[i].get_str());
scriptwitness.stack.push_back(std::move(bytes));
}
return scriptwitness;
}
const std::map<std::string, unsigned int> FLAG_NAMES = {
{std::string("P2SH"), (unsigned int)SCRIPT_VERIFY_P2SH},
{std::string("DERSIG"), (unsigned int)SCRIPT_VERIFY_DERSIG},
{std::string("NULLDUMMY"), (unsigned int)SCRIPT_VERIFY_NULLDUMMY},
{std::string("CHECKLOCKTIMEVERIFY"), (unsigned int)SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY},
{std::string("CHECKSEQUENCEVERIFY"), (unsigned int)SCRIPT_VERIFY_CHECKSEQUENCEVERIFY},
{std::string("WITNESS"), (unsigned int)SCRIPT_VERIFY_WITNESS},
{std::string("TAPROOT"), (unsigned int)SCRIPT_VERIFY_TAPROOT},
};
std::vector<unsigned int> AllFlags()
{
std::vector<unsigned int> ret;
for (unsigned int i = 0; i < 128; ++i) {
unsigned int flag = 0;
if (i & 1) flag |= SCRIPT_VERIFY_P2SH;
if (i & 2) flag |= SCRIPT_VERIFY_DERSIG;
if (i & 4) flag |= SCRIPT_VERIFY_NULLDUMMY;
if (i & 8) flag |= SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY;
if (i & 16) flag |= SCRIPT_VERIFY_CHECKSEQUENCEVERIFY;
if (i & 32) flag |= SCRIPT_VERIFY_WITNESS;
if (i & 64) flag |= SCRIPT_VERIFY_TAPROOT;
// SCRIPT_VERIFY_WITNESS requires SCRIPT_VERIFY_P2SH
if (flag & SCRIPT_VERIFY_WITNESS && !(flag & SCRIPT_VERIFY_P2SH)) continue;
// SCRIPT_VERIFY_TAPROOT requires SCRIPT_VERIFY_WITNESS
if (flag & SCRIPT_VERIFY_TAPROOT && !(flag & SCRIPT_VERIFY_WITNESS)) continue;
ret.push_back(flag);
}
return ret;
}
const std::vector<unsigned int> ALL_FLAGS = AllFlags();
unsigned int ParseScriptFlags(const std::string& str)
{
if (str.empty()) return 0;
unsigned int flags = 0;
std::vector<std::string> words = SplitString(str, ',');
for (const std::string& word : words) {
auto it = FLAG_NAMES.find(word);
if (it == FLAG_NAMES.end()) throw std::runtime_error("Unknown verification flag " + word);
flags |= it->second;
}
return flags;
}
void Test(const std::string& str)
{
UniValue test;
if (!test.read(str) || !test.isObject()) throw std::runtime_error("Non-object test input");
CMutableTransaction tx = TxFromHex(test["tx"].get_str());
const std::vector<CTxOut> prevouts = TxOutsFromJSON(test["prevouts"]);
if (prevouts.size() != tx.vin.size()) throw std::runtime_error("Incorrect number of prevouts");
size_t idx = test["index"].getInt<int64_t>();
if (idx >= tx.vin.size()) throw std::runtime_error("Invalid index");
unsigned int test_flags = ParseScriptFlags(test["flags"].get_str());
bool final = test.exists("final") && test["final"].get_bool();
if (test.exists("success")) {
tx.vin[idx].scriptSig = ScriptFromHex(test["success"]["scriptSig"].get_str());
tx.vin[idx].scriptWitness = ScriptWitnessFromJSON(test["success"]["witness"]);
PrecomputedTransactionData txdata;
txdata.Init(tx, std::vector<CTxOut>(prevouts));
MutableTransactionSignatureChecker txcheck(&tx, idx, prevouts[idx].nValue, txdata, MissingDataBehavior::ASSERT_FAIL);
for (const auto flags : ALL_FLAGS) {
// "final": true tests are valid for all flags. Others are only valid with flags that are
// a subset of test_flags.
if (final || ((flags & test_flags) == flags)) {
(void)VerifyScript(tx.vin[idx].scriptSig, prevouts[idx].scriptPubKey, &tx.vin[idx].scriptWitness, flags, txcheck, nullptr);
}
}
}
if (test.exists("failure")) {
tx.vin[idx].scriptSig = ScriptFromHex(test["failure"]["scriptSig"].get_str());
tx.vin[idx].scriptWitness = ScriptWitnessFromJSON(test["failure"]["witness"]);
PrecomputedTransactionData txdata;
txdata.Init(tx, std::vector<CTxOut>(prevouts));
MutableTransactionSignatureChecker txcheck(&tx, idx, prevouts[idx].nValue, txdata, MissingDataBehavior::ASSERT_FAIL);
for (const auto flags : ALL_FLAGS) {
// If a test is supposed to fail with test_flags, it should also fail with any superset thereof.
if ((flags & test_flags) == test_flags) {
(void)VerifyScript(tx.vin[idx].scriptSig, prevouts[idx].scriptPubKey, &tx.vin[idx].scriptWitness, flags, txcheck, nullptr);
}
}
}
}
void test_init()
{
static ECCVerifyHandle handle;
}
FUZZ_TARGET_INIT_HIDDEN(script_assets_test_minimizer, test_init, /*hidden=*/true)
{
if (buffer.size() < 2 || buffer.back() != '\n' || buffer[buffer.size() - 2] != ',') return;
const std::string str((const char*)buffer.data(), buffer.size() - 2);
try {
Test(str);
} catch (const std::runtime_error&) {
}
}
} // namespace
|
