BIP-325: Signet [consensus] #18267

34+    int cidx = GetWitnessCommitmentIndex();
35+    if (cidx == -1) return false;
36+    auto script = vtx.at(0)->vout.at(cidx).scriptPubKey;
37+    opcodetype opcode;
38+    CScript::const_iterator pc = script.begin();
39+    ++pc; // move beyond initial OP_RETURN

132+     * Returns -1 if no witness commitment was found.
133+     */
134+    template<typename T> static inline int GetWitnessCommitmentIndex(const T& coinbase) {
135+        for (int64_t o = coinbase.vout.size() - 1; o > -1; --o) {
136+            auto vospk = coinbase.vout[o].scriptPubKey;
137+            if (vospk.size() >= 38 && vospk[0] == OP_RETURN && vospk[1] == 0x24 && vospk[2] == 0xaa && vospk[3] == 0x21 && vospk[4] == 0xa9 && vospk[5] == 0xed) {

121+     *
122+     * Returns -1 if no witness commitment was found.
123+     */
124+    inline int GetWitnessCommitmentIndex() const
125+    {
126+        return vtx.empty() ? -1 : GetWitnessCommitmentIndex(*vtx.at(0));

271-        }
272-        bin = ParseHex(args.GetArgs("-signet_blockscript")[0]);
273-        if (args.IsArgSet("-signet_seednode")) {
274-            vSeeds = gArgs.GetArgs("-signet_seednode");
275-        }
276+            LogPrintf("Using default signet network\n");

271+            vSeeds.push_back("ntv3mtqw5wt63red.onion:38333");
272+        } else {
273+            if (args.GetArgs("-signet_blockscript").size() != 1) {
274+                throw std::runtime_error(strprintf("%s: -signet_blockscript cannot be multiple values.", __func__));
275+            }
276+            bin = ParseHex(args.GetArgs("-signet_blockscript")[0]);

294+        consensus.nPowTargetSpacing = 10 * 60;
295+        consensus.fPowAllowMinDifficultyBlocks = false;
296+        consensus.fPowNoRetargeting = false;
297+        consensus.nRuleChangeActivationThreshold = 1916;
298+        consensus.nMinerConfirmationWindow = 2016;
299+        consensus.powLimit = uint256S("00002adc28cf53b63c82faa55d83e40ac63b5f100aa5d8df62a429192f9e8ce5");

323+
324+        bech32_hrp = "sb" + args.GetArg("-signet_hrp", "");
325+
326+        fDefaultConsistencyChecks = false;
327+        fRequireStandard = true;
328+        m_is_test_chain = true;

23@@ -23,6 +24,10 @@ void SetupChainParamsBaseOptions()
24     gArgs.AddArg("-segwitheight=<n>", "Set the activation height of segwit. -1 to disable. (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
25     gArgs.AddArg("-testnet", "Use the test chain. Equivalent to -chain=test.", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
26     gArgs.AddArg("-vbparams=deployment:start:end", "Use given start/end times for specified version bits deployment (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
27+    gArgs.AddArg("-signet", "Use the signet chain. Note that the network is defined by the signet_blockscript parameter", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
28+    gArgs.AddArg("-signet_blockscript", "Blocks must satisfy the given script to be considered valid (only for signet networks)", ArgsManager::ALLOW_STRING, OptionsCategory::CHAINPARAMS);
29+    gArgs.AddArg("-signet_hrp", "Human readable part of bech32 address (suffixed by \"sb\"; default = \"\")", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
30+    gArgs.AddArg("-signet_seednode", "Specify a seed node for the signet network (may be used multiple times to specify multiple seed nodes)", ArgsManager::ALLOW_STRING, OptionsCategory::CHAINPARAMS);

23@@ -23,6 +24,10 @@ void SetupChainParamsBaseOptions()
24     gArgs.AddArg("-segwitheight=<n>", "Set the activation height of segwit. -1 to disable. (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
25     gArgs.AddArg("-testnet", "Use the test chain. Equivalent to -chain=test.", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
26     gArgs.AddArg("-vbparams=deployment:start:end", "Use given start/end times for specified version bits deployment (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
27+    gArgs.AddArg("-signet", "Use the signet chain. Note that the network is defined by the signet_blockscript parameter", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
28+    gArgs.AddArg("-signet_blockscript", "Blocks must satisfy the given script to be considered valid (only for signet networks)", ArgsManager::ALLOW_STRING, OptionsCategory::CHAINPARAMS);
29+    gArgs.AddArg("-signet_hrp", "Human readable part of bech32 address (suffixed by \"sb\"; default = \"\")", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);

45@@ -41,8 +46,9 @@ std::unique_ptr<CBaseChainParams> CreateBaseChainParams(const std::string& chain
46         return MakeUnique<CBaseChainParams>("testnet3", 18332);
47     else if (chain == CBaseChainParams::REGTEST)
48         return MakeUnique<CBaseChainParams>("regtest", 18443);
49-    else
50-        throw std::runtime_error(strprintf("%s: Unknown chain %s.", __func__, chain));
51+    else if (chain == CBaseChainParams::SIGNET)
52+        return MakeUnique<CBaseChainParams>("signet", 38332);

476@@ -396,6 +477,9 @@ std::unique_ptr<const CChainParams> CreateChainParams(const std::string& chain)
477         return std::unique_ptr<CChainParams>(new CTestNetParams());
478     else if (chain == CBaseChainParams::REGTEST)
479         return std::unique_ptr<CChainParams>(new CRegTestParams(gArgs));
480+    else if (chain == CBaseChainParams::SIGNET) {

1151@@ -1151,6 +1152,11 @@ bool ReadBlockFromDisk(CBlock& block, const FlatFilePos& pos, const Consensus::P
1152     if (!CheckProofOfWork(block.GetHash(), block.nBits, consensusParams))
1153         return error("ReadBlockFromDisk: Errors in block header at %s", pos.ToString());
1154 
1155+    if (consensusParams.signet_blocks && block.GetHash() != consensusParams.hashGenesisBlock && !CheckBlockSolution(block, consensusParams)) {

57+    CScript result;
58+    std::vector<uint8_t> pushdata;
59+    auto script = mtx.vout[cidx].scriptPubKey;
60+    opcodetype opcode;
61+    CScript::const_iterator pc = script.begin();
62+    result.push_back(*pc++);

1124@@ -1125,7 +1125,7 @@ BOOST_FIXTURE_TEST_CASE(util_ChainMerge, ChainMergeTestingSetup)
1125     // Results file is formatted like:
1126     //
1127     //   <input> || <output>
1128-    BOOST_CHECK_EQUAL(out_sha_hex, "f0b3a3c29869edc765d579c928f7f1690a71fbb673b49ccf39cbc4de18156a0d");
1129+    BOOST_CHECK_EQUAL(out_sha_hex, "4645298a210e40fd8dfacc2b470be96a186f0ff2ebab328953cfe1ce866e55cf");

140+        }
141+        return -1;
142+    }
143+
144+    /**
145+     * Attempt to get the data for the section with the given header in the witness commitment of this block.

160@@ -161,6 +161,17 @@ class BaseSignatureChecker
161     virtual ~BaseSignatureChecker() {}
162 };
163 
164+/** A low level signature checker.  Note that the caller must verify that the hash passed in relates to a known message (unlike for the other signature checkers). */

262+
263+        std::vector<uint8_t> bin;
264+        vSeeds.clear();
265+
266+        if (!args.IsArgSet("-signet_blockscript")) {
267+            throw std::runtime_error(strprintf("%s: -signet_blockscript is mandatory for signet networks", __func__));

23@@ -23,6 +24,10 @@ void SetupChainParamsBaseOptions()
24     gArgs.AddArg("-segwitheight=<n>", "Set the activation height of segwit. -1 to disable. (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
25     gArgs.AddArg("-testnet", "Use the test chain. Equivalent to -chain=test.", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
26     gArgs.AddArg("-vbparams=deployment:start:end", "Use given start/end times for specified version bits deployment (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
27+    gArgs.AddArg("-signet", "Use the signet chain. Note that the network is defined by the signet_blockscript parameter", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);

269+        if (args.GetArgs("-signet_blockscript").size() != 1) {
270+            throw std::runtime_error(strprintf("%s: -signet_blockscript cannot be multiple values.", __func__));
271+        }
272+        bin = ParseHex(args.GetArgs("-signet_blockscript")[0]);
273+        if (args.IsArgSet("-signet_seednode")) {
274+            vSeeds = gArgs.GetArgs("-signet_seednode");

251@@ -249,13 +252,95 @@ class CTestNetParams : public CChainParams {
252     }
253 };
254 
255+/**
256+ * SigNet

277+            bin = ParseHex(blockscript[0]);
278+            if (args.IsArgSet("-signet_seednode")) {
279+                vSeeds = gArgs.GetArgs("-signet_seednode");
280+            }
281+
282+            LogPrintf("SigNet with block script %s\n", blockscript[0]);

151+    /**
152+     * Get the vout index of the segwit commitment in the given coinbase transaction.
153+     *
154+     * Returns -1 if no witness commitment was found.
155+     */
156+    template<typename T> static inline int GetWitnessCommitmentIndex(const T& coinbase) {

333@@ -332,6 +334,9 @@ bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& pa
334 /** Compute at which vout of the block's coinbase transaction the witness commitment occurs, or -1 if not found */
335 int GetWitnessCommitmentIndex(const CBlock& block);
336 
337+/** Compute at which vout of the given coinbase transaction the witness commitment occurs, or -1 if not found */

48+        // find and delete signet signature
49+        CMutableTransaction mtx(*block.vtx.at(0));
50+        SetWitnessCommitmentSection(mtx, SIGNET_HEADER, std::vector<uint8_t>{});
51+        leaves[0] = mtx.GetHash();
52+    }
53+    for (size_t s = 1; s < block.vtx.size(); s++) {

3413+    for (size_t o = 0; o < tx.vout.size(); o++) {
3414+        const CTxOut& vout = tx.vout[o];
3415+        if (vout.scriptPubKey.size() >= MINIMUM_WITNESS_COMMITMENT &&
3416+            vout.scriptPubKey[0] == OP_RETURN &&
3417+            vout.scriptPubKey[1] == 0x24 &&
3418+            vout.scriptPubKey[2] == 0xaa &&

266+        if (!args.IsArgSet("-signet_blockscript")) {
267+            LogPrintf("Using default signet network\n");
268+            bin = ParseHex("512103ad5e0edad18cb1f0fc0d28a3d4f1f3e445640337489abb10404f2d1e086be43051ae");
269+            vSeeds.push_back("178.128.221.177");
270+            vSeeds.push_back("2a01:7c8:d005:390::5");
271+            vSeeds.push_back("ntv3mtqw5wt63red.onion:38333");

275+                throw std::runtime_error(strprintf("%s: -signet_blockscript cannot be multiple values.", __func__));
276+            }
277+            bin = ParseHex(blockscript[0]);
278+            if (args.IsArgSet("-signet_seednode")) {
279+                vSeeds = gArgs.GetArgs("-signet_seednode");
280+            }

273+        bin = ParseHex(blockscript[0]);
274+        if (args.IsArgSet("-signet_seednode")) {
275+            vSeeds = gArgs.GetArgs("-signet_seednode");
276+        }
277+
278+        LogPrintf("Signet with block script %s\n", blockscript[0]);

23@@ -23,6 +24,10 @@ void SetupChainParamsBaseOptions()
24     gArgs.AddArg("-segwitheight=<n>", "Set the activation height of segwit. -1 to disable. (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::DEBUG_TEST);
25     gArgs.AddArg("-testnet", "Use the test chain. Equivalent to -chain=test.", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
26     gArgs.AddArg("-vbparams=deployment:start:end", "Use given start/end times for specified version bits deployment (regtest-only)", ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::CHAINPARAMS);
27+    gArgs.AddArg("-signet", "Use the signet chain. Note that the network is defined by the signet_blockscript parameter", ArgsManager::ALLOW_ANY, OptionsCategory::CHAINPARAMS);
28+    gArgs.AddArg("-signet_blockscript", "Blocks must satisfy the given script to be considered valid (only for signet networks)", ArgsManager::ALLOW_STRING, OptionsCategory::CHAINPARAMS);

 9+#include <config/bitcoin-config.h>
10+#endif
11+
12+#include <consensus/params.h>
13+
14+#include <stdint.h>

40+    std::vector<uint256> leaves;
41+    leaves.resize(block.vtx.size());
42+    {
43+        // find and delete signet signature
44+        CMutableTransaction mtx(*block.vtx.at(0));
45+        SetWitnessCommitmentSection(mtx, SIGNET_HEADER, std::vector<uint8_t>{});

14+#include <util/system.h>
15+
16+int GetWitnessCommitmentIndex(const CBlock& block);
17+template<typename T> int GetWitnessCommitmentIndex(const T& tx);
18+
19+static constexpr int NO_WITNESS_COMMITMENT{-1}; // note: this is copied from validation.h, to avoid a circular dependency issue

13+#include <script/interpreter.h>
14+#include <script/standard.h>        // MANDATORY_SCRIPT_VERIFY_FLAGS
15+#include <util/system.h>
16+
17+int GetWitnessCommitmentIndex(const CBlock& block);
18+template<typename T> int GetWitnessCommitmentIndex(const T& tx);

1500@@ -1501,6 +1501,18 @@ bool GenericTransactionSignatureChecker<T>::CheckSequence(const CScriptNum& nSeq
1501 template class GenericTransactionSignatureChecker<CTransaction>;
1502 template class GenericTransactionSignatureChecker<CMutableTransaction>;
1503 
1504+bool SimpleSignatureChecker::CheckSig(const std::vector<unsigned char>& vchSigIn, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const

23+    }
24+    SimpleSignatureChecker bsc(GetSignetHash(block));
25+    CScript challenge(consensusParams.signet_challenge.begin(), consensusParams.signet_challenge.end());
26+    CScript solution = CScript(signet_data.begin(), signet_data.end());
27+
28+    if (!VerifyScript(solution, challenge, nullptr, MANDATORY_SCRIPT_VERIFY_FLAGS, bsc)) {

3324@@ -3318,6 +3325,11 @@ bool CheckBlock(const CBlock& block, BlockValidationState& state, const Consensu
3325     if (!CheckBlockHeader(block, state, consensusParams, fCheckPOW))
3326         return false;
3327 
3328+    // Signet only: check block solution, unless this is the genesis block
3329+    if (consensusParams.signet_blocks && fCheckPOW && block.GetHash() != consensusParams.hashGenesisBlock && !CheckBlockSolution(block, consensusParams)) {
3330+        return false;

15+#include <util/system.h>
16+
17+// Signet block solution checker
18+bool CheckBlockSolution(const CBlock& block, const Consensus::Params& consensusParams)
19+{
20+    std::vector<uint8_t> signet_data;

135@@ -136,7 +136,7 @@ BOOST_AUTO_TEST_CASE(key_io_invalid)
136         std::string exp_base58string = test[0].get_str();
137 
138         // must be invalid as public and as private key
139-        for (const auto& chain : { CBaseChainParams::MAIN, CBaseChainParams::TESTNET, CBaseChainParams::REGTEST }) {
140+        for (const auto& chain : { CBaseChainParams::MAIN, CBaseChainParams::TESTNET, CBaseChainParams::SIGNET, CBaseChainParams::REGTEST }) {
141             SelectParams(chain);
142             destination = DecodeDestination(exp_base58string);
143             BOOST_CHECK_MESSAGE(!IsValidDestination(destination), "IsValid pubkey in mainnet:" + strTest);

274+            if (blockscript.size() != 1) {
275+                throw std::runtime_error(strprintf("%s: -signet_blockscript cannot be multiple values.", __func__));
276+            }
277+            bin = ParseHex(blockscript[0]);
278+
279+            LogPrintf("Signet with block script %s\n", blockscript[0]);

263+        std::vector<uint8_t> bin;
264+        vSeeds.clear();
265+
266+        if (!args.IsArgSet("-signet_blockscript")) {
267+            LogPrintf("Using default signet network\n");
268+            bin = ParseHex("512103ad5e0edad18cb1f0fc0d28a3d4f1f3e445640337489abb10404f2d1e086be43051ae");

54+}
55+
56+bool GetWitnessCommitmentSection(const CBlock& block, const uint8_t header[4], std::vector<uint8_t>& result)
57+{
58+    int cidx = GetWitnessCommitmentIndex(block);
59+    if (cidx == NO_WITNESS_COMMITMENT) return false;

36+/**
37+ * Attempt to get the data for the section with the given header in the witness commitment of the block.
38+ *
39+ * Returns false if header was not found. The data (excluding the 4 byte header) is written into result if found.
40+ */
41+bool GetWitnessCommitmentSection(const CBlock& block, const uint8_t header[4], std::vector<uint8_t>& result);

326+        base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x35, 0x83, 0x94};
327+
328+        bech32_hrp = "sb";
329+
330+        fDefaultConsistencyChecks = false;
331+        fRequireStandard = true;

149+
150+/** Compute at which vout of the block's coinbase transaction the witness commitment occurs, or -1 if not found */
151+int GetWitnessCommitmentIndex(const CBlock& block);
152+
153+/** Compute at which vout of the given coinbase transaction the witness commitment occurs, or -1 if not found */
154+template<typename T> int GetWitnessCommitmentIndex(const T& tx);