/root/bitcoin/src/rpc/txoutproof.cpp

Source
// 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/blockchain.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;

static RPCHelpMan gettxoutproof()
{
    return RPCHelpMan{
        "gettxoutproof",
        "Returns 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, "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<Txid> 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(Txid::FromUint256(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();
            }

            if (pblockindex == nullptr) {
                const CTransactionRef tx = GetTransaction(/*block_index=*/nullptr, /*mempool=*/nullptr, *setTxids.begin(), hashBlock, chainman.m_blockman);
                if (!tx || hashBlock.IsNull()) {
                    throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction not yet in block");
                }

                LOCK(cs_main);
                pblockindex = chainman.m_blockman.LookupBlockIndex(hashBlock);
                if (!pblockindex) {
                    throw JSONRPCError(RPC_INTERNAL_ERROR, "Transaction index corrupt");
                }
            }

            {
                LOCK(cs_main);
                CheckBlockDataAvailability(chainman.m_blockman, *pblockindex, /*check_for_undo=*/false);
            }
            CBlock block;
            if (!chainman.m_blockman.ReadBlock(block, *pblockindex)) {
                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");
            }

            DataStream ssMB{};
            CMerkleBlock mb(block, setTxids);
            ssMB << mb;
            std::string strHex = HexStr(ssMB);
            return strHex;
        },
    };
}

static RPCHelpMan verifytxoutproof()
{
    return RPCHelpMan{
        "verifytxoutproof",
        "Verifies 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
        {
            DataStream ssMB{ParseHexV(request.params[0], "proof")};
            CMerkleBlock merkleBlock;
            ssMB >> merkleBlock;

            UniValue res(UniValue::VARR);

            std::vector<Txid> 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 auto& txid : vMatch) {
                    res.push_back(txid.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);
    }
}

Line	Count	Source
1		// Copyright (c) 2010 Satoshi Nakamoto
2		// Copyright (c) 2009-2022 The Bitcoin Core developers
3		// Distributed under the MIT software license, see the accompanying
4		// file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6		#include <chain.h>
7		#include <chainparams.h>
8		#include <coins.h>
9		#include <index/txindex.h>
10		#include <merkleblock.h>
11		#include <node/blockstorage.h>
12		#include <primitives/transaction.h>
13		#include <rpc/blockchain.h>
14		#include <rpc/server.h>
15		#include <rpc/server_util.h>
16		#include <rpc/util.h>
17		#include <univalue.h>
18		#include <util/strencodings.h>
19		#include <validation.h>
20
21		using node::GetTransaction;
22
23		static RPCHelpMan gettxoutproof()
24	6	{
25	6	return RPCHelpMan{
26	6	"gettxoutproof",
27	6	"Returns a hex-encoded proof that \"txid\" was included in a block.\n"
28	6	"\nNOTE: By default this function only works sometimes. This is when there is an\n"
29	6	"unspent output in the utxo for this transaction. To make it always work,\n"
30	6	"you need to maintain a transaction index, using the -txindex command line option or\n"
31	6	"specify the block in which the transaction is included manually (by blockhash).\n",
32	6	{
33	6	{"txids", RPCArg::Type::ARR, RPCArg::Optional::NO, "The txids to filter",
34	6	{
35	6	{"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "A transaction hash"},
36	6	},
37	6	},
38	6	{"blockhash", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "If specified, looks for txid in the block with this hash"},
39	6	},
40	6	RPCResult{
41	6	RPCResult::Type::STR, "data", "A string that is a serialized, hex-encoded data for the proof."
42	6	},
43	6	RPCExamples{""},
44	6	[&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
45	6	{
46	0	std::set<Txid> setTxids;
47	0	UniValue txids = request.params[0].get_array();
48	0	if (txids.empty()) {
49	0	throw JSONRPCError(RPC_INVALID_PARAMETER, "Parameter 'txids' cannot be empty");
50	0	}
51	0	for (unsigned int idx = 0; idx < txids.size(); idx++) {
52	0	auto ret{setTxids.insert(Txid::FromUint256(ParseHashV(txids[idx], "txid")))};
53	0	if (!ret.second) {
54	0	throw JSONRPCError(RPC_INVALID_PARAMETER, std::string("Invalid parameter, duplicated txid: ") + txids[idx].get_str());
55	0	}
56	0	}
57
58	0	const CBlockIndex* pblockindex = nullptr;
59	0	uint256 hashBlock;
60	0	ChainstateManager& chainman = EnsureAnyChainman(request.context);
61	0	if (!request.params[1].isNull()) {
62	0	LOCK(cs_main);
63	0	hashBlock = ParseHashV(request.params[1], "blockhash");
64	0	pblockindex = chainman.m_blockman.LookupBlockIndex(hashBlock);
65	0	if (!pblockindex) {
66	0	throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
67	0	}
68	0	} else {
69	0	LOCK(cs_main);
70	0	Chainstate& active_chainstate = chainman.ActiveChainstate();
71
72		// Loop through txids and try to find which block they're in. Exit loop once a block is found.
73	0	for (const auto& tx : setTxids) {
74	0	const Coin& coin{AccessByTxid(active_chainstate.CoinsTip(), tx)};
75	0	if (!coin.IsSpent()) {
76	0	pblockindex = active_chainstate.m_chain[coin.nHeight];
77	0	break;
78	0	}
79	0	}
80	0	}
81
82
83		// Allow txindex to catch up if we need to query it and before we acquire cs_main.
84	0	if (g_txindex && !pblockindex) {
85	0	g_txindex->BlockUntilSyncedToCurrentChain();
86	0	}
87
88	0	if (pblockindex == nullptr) {
89	0	const CTransactionRef tx = GetTransaction(/block_index=/nullptr, /mempool=/nullptr, *setTxids.begin(), hashBlock, chainman.m_blockman);
90	0	if (!tx \|\| hashBlock.IsNull()) {
91	0	throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction not yet in block");
92	0	}
93
94	0	LOCK(cs_main);
95	0	pblockindex = chainman.m_blockman.LookupBlockIndex(hashBlock);
96	0	if (!pblockindex) {
97	0	throw JSONRPCError(RPC_INTERNAL_ERROR, "Transaction index corrupt");
98	0	}
99	0	}
100
101	0	{
102	0	LOCK(cs_main);
103	0	CheckBlockDataAvailability(chainman.m_blockman, pblockindex, /check_for_undo=*/false);
104	0	}
105	0	CBlock block;
106	0	if (!chainman.m_blockman.ReadBlock(block, *pblockindex)) {
107	0	throw JSONRPCError(RPC_INTERNAL_ERROR, "Can't read block from disk");
108	0	}
109
110	0	unsigned int ntxFound = 0;
111	0	for (const auto& tx : block.vtx) {
112	0	if (setTxids.count(tx->GetHash())) {
113	0	ntxFound++;
114	0	}
115	0	}
116	0	if (ntxFound != setTxids.size()) {
117	0	throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Not all transactions found in specified or retrieved block");
118	0	}
119
120	0	DataStream ssMB{};
121	0	CMerkleBlock mb(block, setTxids);
122	0	ssMB << mb;
123	0	std::string strHex = HexStr(ssMB);
124	0	return strHex;
125	0	},
126	6	};
127	6	}
128
129		static RPCHelpMan verifytxoutproof()
130	48	{
131	48	return RPCHelpMan{
132	48	"verifytxoutproof",
133	48	"Verifies that a proof points to a transaction in a block, returning the transaction it commits to\n"
134	48	"and throwing an RPC error if the block is not in our best chain\n",
135	48	{
136	48	{"proof", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The hex-encoded proof generated by gettxoutproof"},
137	48	},
138	48	RPCResult{
139	48	RPCResult::Type::ARR, "", "",
140	48	{
141	48	{RPCResult::Type::STR_HEX, "txid", "The txid(s) which the proof commits to, or empty array if the proof cannot be validated."},
142	48	}
143	48	},
144	48	RPCExamples{""},
145	48	[&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
146	48	{
147	41	DataStream ssMB{ParseHexV(request.params[0], "proof")};
148	41	CMerkleBlock merkleBlock;
149	41	ssMB >> merkleBlock;
150
151	41	UniValue res(UniValue::VARR);
152
153	41	std::vector<Txid> vMatch;
154	41	std::vector<unsigned int> vIndex;
155	41	if (merkleBlock.txn.ExtractMatches(vMatch, vIndex) != merkleBlock.header.hashMerkleRoot)
156	35	return res;
157
158	6	ChainstateManager& chainman = EnsureAnyChainman(request.context);
159	6	LOCK(cs_main);
160
161	6	const CBlockIndex* pindex = chainman.m_blockman.LookupBlockIndex(merkleBlock.header.GetHash());
162	6	if (!pindex \|\| !chainman.ActiveChain().Contains(pindex) \|\| pindex->nTx == 0) {
163	2	throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found in chain");
164	2	}
165
166		// Check if proof is valid, only add results if so
167	4	if (pindex->nTx == merkleBlock.txn.GetNumTransactions()) {
168	0	for (const auto& txid : vMatch) {
169	0	res.push_back(txid.GetHex());
170	0	}
171	0	}
172
173	4	return res;
174	6	},
175	48	};
176	48	}
177
178		void RegisterTxoutProofRPCCommands(CRPCTable& t)
179	0	{
180	0	static const CRPCCommand commands[]{
181	0	{"blockchain", &gettxoutproof},
182	0	{"blockchain", &verifytxoutproof},
183	0	};
184	0	for (const auto& c : commands) {
185	0	t.appendCommand(c.name, &c);
186	0	}
187	0	}

Coverage Report

Created: 2025-09-08 17:06