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
|
// Copyright (c) 2010 Satoshi Nakamoto
// Copyright (c) 2009-2022 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 <chain.h>
#include <chainparams.h>
#include <coins.h>
#include <index/txindex.h>
#include <merkleblock.h>
#include <node/blockstorage.h>
#include <primitives/transaction.h>
#include <rpc/server.h>
#include <rpc/server_util.h>
#include <rpc/util.h>
#include <univalue.h>
#include <util/strencodings.h>
#include <validation.h>
using node::GetTransaction;
using node::ReadBlockFromDisk;
static RPCHelpMan gettxoutproof()
{
return RPCHelpMan{"gettxoutproof",
"\nReturns a hex-encoded proof that \"txid\" was included in a block.\n"
"\nNOTE: By default this function only works sometimes. This is when there is an\n"
"unspent output in the utxo for this transaction. To make it always work,\n"
"you need to maintain a transaction index, using the -txindex command line option or\n"
"specify the block in which the transaction is included manually (by blockhash).\n",
{
{"txids", RPCArg::Type::ARR, RPCArg::Optional::NO, "The txids to filter",
{
{"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "A transaction hash"},
},
},
{"blockhash", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED_NAMED_ARG, "If specified, looks for txid in the block with this hash"},
},
RPCResult{
RPCResult::Type::STR, "data", "A string that is a serialized, hex-encoded data for the proof."
},
RPCExamples{""},
[&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
std::set<uint256> setTxids;
UniValue txids = request.params[0].get_array();
if (txids.empty()) {
throw JSONRPCError(RPC_INVALID_PARAMETER, "Parameter 'txids' cannot be empty");
}
for (unsigned int idx = 0; idx < txids.size(); idx++) {
auto ret = setTxids.insert(ParseHashV(txids[idx], "txid"));
if (!ret.second) {
throw JSONRPCError(RPC_INVALID_PARAMETER, std::string("Invalid parameter, duplicated txid: ") + txids[idx].get_str());
}
}
const CBlockIndex* pblockindex = nullptr;
uint256 hashBlock;
ChainstateManager& chainman = EnsureAnyChainman(request.context);
if (!request.params[1].isNull()) {
LOCK(cs_main);
hashBlock = ParseHashV(request.params[1], "blockhash");
pblockindex = chainman.m_blockman.LookupBlockIndex(hashBlock);
if (!pblockindex) {
throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
}
} else {
LOCK(cs_main);
Chainstate& active_chainstate = chainman.ActiveChainstate();
// Loop through txids and try to find which block they're in. Exit loop once a block is found.
for (const auto& tx : setTxids) {
const Coin& coin = AccessByTxid(active_chainstate.CoinsTip(), tx);
if (!coin.IsSpent()) {
pblockindex = active_chainstate.m_chain[coin.nHeight];
break;
}
}
}
// Allow txindex to catch up if we need to query it and before we acquire cs_main.
if (g_txindex && !pblockindex) {
g_txindex->BlockUntilSyncedToCurrentChain();
}
LOCK(cs_main);
if (pblockindex == nullptr) {
const CTransactionRef tx = GetTransaction(/*block_index=*/nullptr, /*mempool=*/nullptr, *setTxids.begin(), chainman.GetConsensus(), hashBlock);
if (!tx || hashBlock.IsNull()) {
throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction not yet in block");
}
pblockindex = chainman.m_blockman.LookupBlockIndex(hashBlock);
if (!pblockindex) {
throw JSONRPCError(RPC_INTERNAL_ERROR, "Transaction index corrupt");
}
}
CBlock block;
if (!ReadBlockFromDisk(block, pblockindex, chainman.GetConsensus())) {
throw JSONRPCError(RPC_INTERNAL_ERROR, "Can't read block from disk");
}
unsigned int ntxFound = 0;
for (const auto& tx : block.vtx) {
if (setTxids.count(tx->GetHash())) {
ntxFound++;
}
}
if (ntxFound != setTxids.size()) {
throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Not all transactions found in specified or retrieved block");
}
CDataStream ssMB(SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS);
CMerkleBlock mb(block, setTxids);
ssMB << mb;
std::string strHex = HexStr(ssMB);
return strHex;
},
};
}
static RPCHelpMan verifytxoutproof()
{
return RPCHelpMan{"verifytxoutproof",
"\nVerifies that a proof points to a transaction in a block, returning the transaction it commits to\n"
"and throwing an RPC error if the block is not in our best chain\n",
{
{"proof", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The hex-encoded proof generated by gettxoutproof"},
},
RPCResult{
RPCResult::Type::ARR, "", "",
{
{RPCResult::Type::STR_HEX, "txid", "The txid(s) which the proof commits to, or empty array if the proof cannot be validated."},
}
},
RPCExamples{""},
[&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
{
CDataStream ssMB(ParseHexV(request.params[0], "proof"), SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS);
CMerkleBlock merkleBlock;
ssMB >> merkleBlock;
UniValue res(UniValue::VARR);
std::vector<uint256> vMatch;
std::vector<unsigned int> vIndex;
if (merkleBlock.txn.ExtractMatches(vMatch, vIndex) != merkleBlock.header.hashMerkleRoot)
return res;
ChainstateManager& chainman = EnsureAnyChainman(request.context);
LOCK(cs_main);
const CBlockIndex* pindex = chainman.m_blockman.LookupBlockIndex(merkleBlock.header.GetHash());
if (!pindex || !chainman.ActiveChain().Contains(pindex) || pindex->nTx == 0) {
throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found in chain");
}
// Check if proof is valid, only add results if so
if (pindex->nTx == merkleBlock.txn.GetNumTransactions()) {
for (const uint256& hash : vMatch) {
res.push_back(hash.GetHex());
}
}
return res;
},
};
}
void RegisterTxoutProofRPCCommands(CRPCTable& t)
{
static const CRPCCommand commands[]{
{"blockchain", &gettxoutproof},
{"blockchain", &verifytxoutproof},
};
for (const auto& c : commands) {
t.appendCommand(c.name, &c);
}
}
|
