diff options
| author | Wladimir J. van der Laan <laanwj@protonmail.com> | 2020-10-15 09:46:03 +0200 |
|---|---|---|
| committer | Wladimir J. van der Laan <laanwj@protonmail.com> | 2020-10-15 10:22:35 +0200 |
| commit | 3caee16946575e71e90ead9ac531f5a3a1259307 (patch) | |
| tree | 4d7646f5c8d049a6099b603fbd8d451370865c99 /src | |
| parent | 8ed37f6c8497c8ec9e919dab35f63201e5f75f11 (diff) | |
| parent | 0e2a5e448f426219a6464b9aaadcc715534114e6 (diff) | |
| download | bitcoin-3caee16946575e71e90ead9ac531f5a3a1259307.tar.xz | |
Merge #19953: Implement BIP 340-342 validation (Schnorr/taproot/tapscript)
0e2a5e448f426219a6464b9aaadcc715534114e6 tests: dumping and minimizing of script assets data (Pieter Wuille)
4567ba034c5ae6e6cc161360f7425c9e844738f0 tests: add generic qa-asset-based script verification unit test (Pieter Wuille)
f06e6d03452cf5e0b1a0863afb08c9e6d3ef452e tests: functional tests for Schnorr/Taproot/Tapscript (Pieter Wuille)
3c226639eb134314a0640d34e4ccb6148dbde22f tests: add BIP340 Schnorr signature support to test framework (Pieter Wuille)
206fb180ec6ee5f916afc6f574000d716daf79b7 --- [TAPROOT] Tests --- (Pieter Wuille)
d7ff237f2996a4c11fdf9399187c2d2b26bf9809 Activate Taproot/Tapscript on regtest (BIP 341, BIP 342) (Pieter Wuille)
e9a021d7e6a454d610a45cb9b3995f0d96a5fbb6 Make Taproot spends standard + policy limits (Pieter Wuille)
865d2c37e2e44678498b7f425b65e01b1e231cde --- [TAPROOT] Regtest activation and policy --- (Pieter Wuille)
72422ce396b8eba7b1a72c171c2f07dae691d1b5 Implement Tapscript script validation rules (BIP 342) (Johnson Lau)
330de894a9a48515d9a473448b6c67adc3d188be Use ScriptExecutionData to pass through annex hash (Pieter Wuille)
8bbed4b7acf4c76eaea8c0e10f3cbf6ba4e53809 Implement Taproot validation (BIP 341) (Pieter Wuille)
0664f5fe1f77f08d235aa3750b59428257b0b91d Support for Schnorr signatures and integration in SignatureCheckers (BIP 340) (Pieter Wuille)
5de246ca8159dcffaa4c136a60c8bfed2028e2ee Implement Taproot signature hashing (BIP 341) (Johnson Lau)
9eb590894f15ff40806039bfd32972fbc260e30d Add TaggedHash function (BIP 340) (Pieter Wuille)
450d2b23710ad296eede81339195376021ab5500 --- [TAPROOT] BIP340/341/342 consensus rules --- (Pieter Wuille)
5d62e3a68b6ea9bb03556ee1fbf5678f20be01a2 refactor: keep spent outputs in PrecomputedTransactionData (Pieter Wuille)
8bd2b4e78452ff69c08c37acf164a6b80e503f13 refactor: rename scriptPubKey in VerifyWitnessProgram to exec_script (Pieter Wuille)
107b57df9fa8b2d625d2b342dc77722282a6ae4c scripted-diff: put ECDSA in name of signature functions (Pieter Wuille)
f8c099e2207c90d758e7a659d6a55fa7ccb7ceaa --- [TAPROOT] Refactors --- (Pieter Wuille)
Pull request description:
This is an implementation of the Schnorr/taproot consensus rules proposed by BIPs [340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki), [341](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki), and [342](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki).
See the list of commits [below](https://github.com/bitcoin/bitcoin/pull/19953#issuecomment-691815830). No signing or wallet support of any kind is included, as testing is done entirely through the Python test framework.
This is a successor to https://github.com/bitcoin/bitcoin/pull/17977 (see discussion following [this comment](https://github.com/bitcoin/bitcoin/pull/17977#issuecomment-682285983)), and will have further changes squashed/rebased. The history of this PR can be found in #19997.
ACKs for top commit:
instagibbs:
reACK https://github.com/bitcoin/bitcoin/pull/19953/commits/0e2a5e448f426219a6464b9aaadcc715534114e6
benthecarman:
reACK 0e2a5e4
kallewoof:
reACK 0e2a5e448f426219a6464b9aaadcc715534114e6
jonasnick:
ACK 0e2a5e448f426219a6464b9aaadcc715534114e6 almost only looked at bip340/libsecp related code
jonatack:
ACK 0e2a5e448f426219a6464b9aaadcc715534114e6 modulo the last four commits (tests) that I plan to finish reviewing tomorrow
fjahr:
reACK 0e2a5e448f426219a6464b9aaadcc715534114e6
achow101:
ACK 0e2a5e448f426219a6464b9aaadcc715534114e6
Tree-SHA512: 1b00314450a2938a22bccbb4e177230cf08bd365d72055f9d526891f334b364c997e260c10bc19ca78440b6767712c9feea7faad9a1045dd51a5b96f7ca8146e
Diffstat (limited to 'src')
32 files changed, 1157 insertions, 90 deletions
diff --git a/src/Makefile.test.include b/src/Makefile.test.include index 835b12ce3e..7fac78f973 100644 --- a/src/Makefile.test.include +++ b/src/Makefile.test.include @@ -129,6 +129,7 @@ FUZZ_TARGETS = \ test/fuzz/script_deserialize \ test/fuzz/script_flags \ test/fuzz/script_interpreter \ + test/fuzz/script_assets_test_minimizer \ test/fuzz/script_ops \ test/fuzz/script_sigcache \ test/fuzz/script_sign \ @@ -1083,6 +1084,12 @@ test_fuzz_script_interpreter_LDADD = $(FUZZ_SUITE_LD_COMMON) test_fuzz_script_interpreter_LDFLAGS = $(FUZZ_SUITE_LDFLAGS_COMMON) test_fuzz_script_interpreter_SOURCES = test/fuzz/script_interpreter.cpp +test_fuzz_script_assets_test_minimizer_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) +test_fuzz_script_assets_test_minimizer_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS) +test_fuzz_script_assets_test_minimizer_LDADD = $(FUZZ_SUITE_LD_COMMON) +test_fuzz_script_assets_test_minimizer_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(LIBTOOL_APP_LDFLAGS) +test_fuzz_script_assets_test_minimizer_SOURCES = test/fuzz/script_assets_test_minimizer.cpp + test_fuzz_script_ops_CPPFLAGS = $(AM_CPPFLAGS) $(BITCOIN_INCLUDES) test_fuzz_script_ops_CXXFLAGS = $(AM_CXXFLAGS) $(PIE_FLAGS) test_fuzz_script_ops_LDADD = $(FUZZ_SUITE_LD_COMMON) diff --git a/src/chainparams.cpp b/src/chainparams.cpp index ef501e9de2..a34bf350fc 100644 --- a/src/chainparams.cpp +++ b/src/chainparams.cpp @@ -86,6 +86,11 @@ public: consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008 consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008 + // Deployment of Taproot (BIPs 340-342) + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2; + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1199145601; // January 1, 2008 + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1230767999; // December 31, 2008 + // The best chain should have at least this much work. consensus.nMinimumChainWork = uint256S("0x00000000000000000000000000000000000000000e1ab5ec9348e9f4b8eb8154"); @@ -197,6 +202,11 @@ public: consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 1199145601; // January 1, 2008 consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = 1230767999; // December 31, 2008 + // Deployment of Taproot (BIPs 340-342) + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2; + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1199145601; // January 1, 2008 + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1230767999; // December 31, 2008 + // The best chain should have at least this much work. consensus.nMinimumChainWork = uint256S("0x0000000000000000000000000000000000000000000001495c1d5a01e2af8a23"); @@ -380,6 +390,9 @@ public: consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].bit = 28; consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nStartTime = 0; consensus.vDeployments[Consensus::DEPLOYMENT_TESTDUMMY].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT; + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].bit = 2; + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE; + consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT; // The best chain should have at least this much work. consensus.nMinimumChainWork = uint256S("0x00"); diff --git a/src/consensus/params.h b/src/consensus/params.h index 85ab3f61ef..932f0d2c60 100644 --- a/src/consensus/params.h +++ b/src/consensus/params.h @@ -14,6 +14,7 @@ namespace Consensus { enum DeploymentPos { DEPLOYMENT_TESTDUMMY, + DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342) // NOTE: Also add new deployments to VersionBitsDeploymentInfo in versionbits.cpp MAX_VERSION_BITS_DEPLOYMENTS }; diff --git a/src/hash.cpp b/src/hash.cpp index 83b90ae063..3657b38639 100644 --- a/src/hash.cpp +++ b/src/hash.cpp @@ -6,6 +6,7 @@ #include <crypto/common.h> #include <crypto/hmac_sha512.h> +#include <string> inline uint32_t ROTL32(uint32_t x, int8_t r) { @@ -84,3 +85,12 @@ uint256 SHA256Uint256(const uint256& input) CSHA256().Write(input.begin(), 32).Finalize(result.begin()); return result; } + +CHashWriter TaggedHash(const std::string& tag) +{ + CHashWriter writer(SER_GETHASH, 0); + uint256 taghash; + CSHA256().Write((const unsigned char*)tag.data(), tag.size()).Finalize(taghash.begin()); + writer << taghash << taghash; + return writer; +} diff --git a/src/hash.h b/src/hash.h index c16bbb48ce..6d876076ee 100644 --- a/src/hash.h +++ b/src/hash.h @@ -15,6 +15,7 @@ #include <uint256.h> #include <version.h> +#include <string> #include <vector> typedef uint256 ChainCode; @@ -202,4 +203,12 @@ unsigned int MurmurHash3(unsigned int nHashSeed, Span<const unsigned char> vData void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64]); +/** Return a CHashWriter primed for tagged hashes (as specified in BIP 340). + * + * The returned object will have SHA256(tag) written to it twice (= 64 bytes). + * A tagged hash can be computed by feeding the message into this object, and + * then calling CHashWriter::GetSHA256(). + */ +CHashWriter TaggedHash(const std::string& tag); + #endif // BITCOIN_HASH_H diff --git a/src/policy/policy.cpp b/src/policy/policy.cpp index 0e9820da1e..69f2b456f1 100644 --- a/src/policy/policy.cpp +++ b/src/policy/policy.cpp @@ -9,7 +9,7 @@ #include <consensus/validation.h> #include <coins.h> - +#include <span.h> CAmount GetDustThreshold(const CTxOut& txout, const CFeeRate& dustRelayFeeIn) { @@ -206,6 +206,7 @@ bool IsWitnessStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs) // get the scriptPubKey corresponding to this input: CScript prevScript = prev.scriptPubKey; + bool p2sh = false; if (prevScript.IsPayToScriptHash()) { std::vector <std::vector<unsigned char> > stack; // If the scriptPubKey is P2SH, we try to extract the redeemScript casually by converting the scriptSig @@ -216,6 +217,7 @@ bool IsWitnessStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs) if (stack.empty()) return false; prevScript = CScript(stack.back().begin(), stack.back().end()); + p2sh = true; } int witnessversion = 0; @@ -237,6 +239,36 @@ bool IsWitnessStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs) return false; } } + + // Check policy limits for Taproot spends: + // - MAX_STANDARD_TAPSCRIPT_STACK_ITEM_SIZE limit for stack item size + // - No annexes + if (witnessversion == 1 && witnessprogram.size() == WITNESS_V1_TAPROOT_SIZE && !p2sh) { + // Taproot spend (non-P2SH-wrapped, version 1, witness program size 32; see BIP 341) + auto stack = MakeSpan(tx.vin[i].scriptWitness.stack); + if (stack.size() >= 2 && !stack.back().empty() && stack.back()[0] == ANNEX_TAG) { + // Annexes are nonstandard as long as no semantics are defined for them. + return false; + } + if (stack.size() >= 2) { + // Script path spend (2 or more stack elements after removing optional annex) + const auto& control_block = SpanPopBack(stack); + SpanPopBack(stack); // Ignore script + if (control_block.empty()) return false; // Empty control block is invalid + if ((control_block[0] & TAPROOT_LEAF_MASK) == TAPROOT_LEAF_TAPSCRIPT) { + // Leaf version 0xc0 (aka Tapscript, see BIP 342) + for (const auto& item : stack) { + if (item.size() > MAX_STANDARD_TAPSCRIPT_STACK_ITEM_SIZE) return false; + } + } + } else if (stack.size() == 1) { + // Key path spend (1 stack element after removing optional annex) + // (no policy rules apply) + } else { + // 0 stack elements; this is already invalid by consensus rules + return false; + } + } } return true; } diff --git a/src/policy/policy.h b/src/policy/policy.h index 7f168ee20f..51d67b9390 100644 --- a/src/policy/policy.h +++ b/src/policy/policy.h @@ -40,6 +40,8 @@ static const bool DEFAULT_PERMIT_BAREMULTISIG = true; static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEMS = 100; /** The maximum size of each witness stack item in a standard P2WSH script */ static const unsigned int MAX_STANDARD_P2WSH_STACK_ITEM_SIZE = 80; +/** The maximum size of each witness stack item in a standard BIP 342 script (Taproot, leaf version 0xc0) */ +static const unsigned int MAX_STANDARD_TAPSCRIPT_STACK_ITEM_SIZE = 80; /** The maximum size of a standard witnessScript */ static const unsigned int MAX_STANDARD_P2WSH_SCRIPT_SIZE = 3600; /** Min feerate for defining dust. Historically this has been based on the @@ -68,7 +70,11 @@ static constexpr unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VE SCRIPT_VERIFY_WITNESS | SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM | SCRIPT_VERIFY_WITNESS_PUBKEYTYPE | - SCRIPT_VERIFY_CONST_SCRIPTCODE; + SCRIPT_VERIFY_CONST_SCRIPTCODE | + SCRIPT_VERIFY_TAPROOT | + SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION | + SCRIPT_VERIFY_DISCOURAGE_OP_SUCCESS | + SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_PUBKEYTYPE; /** For convenience, standard but not mandatory verify flags. */ static constexpr unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS; diff --git a/src/pubkey.cpp b/src/pubkey.cpp index fc14f41a0c..4d734fc891 100644 --- a/src/pubkey.cpp +++ b/src/pubkey.cpp @@ -7,6 +7,7 @@ #include <secp256k1.h> #include <secp256k1_recovery.h> +#include <secp256k1_schnorrsig.h> namespace { @@ -166,6 +167,27 @@ int ecdsa_signature_parse_der_lax(const secp256k1_context* ctx, secp256k1_ecdsa_ return 1; } +XOnlyPubKey::XOnlyPubKey(Span<const unsigned char> bytes) +{ + assert(bytes.size() == 32); + std::copy(bytes.begin(), bytes.end(), m_keydata.begin()); +} + +bool XOnlyPubKey::VerifySchnorr(const uint256& msg, Span<const unsigned char> sigbytes) const +{ + assert(sigbytes.size() == 64); + secp256k1_xonly_pubkey pubkey; + if (!secp256k1_xonly_pubkey_parse(secp256k1_context_verify, &pubkey, m_keydata.data())) return false; + return secp256k1_schnorrsig_verify(secp256k1_context_verify, sigbytes.data(), msg.begin(), &pubkey); +} + +bool XOnlyPubKey::CheckPayToContract(const XOnlyPubKey& base, const uint256& hash, bool parity) const +{ + secp256k1_xonly_pubkey base_point; + if (!secp256k1_xonly_pubkey_parse(secp256k1_context_verify, &base_point, base.data())) return false; + return secp256k1_xonly_pubkey_tweak_add_check(secp256k1_context_verify, m_keydata.begin(), parity, &base_point, hash.begin()); +} + bool CPubKey::Verify(const uint256 &hash, const std::vector<unsigned char>& vchSig) const { if (!IsValid()) return false; diff --git a/src/pubkey.h b/src/pubkey.h index fcbc7e8416..0f784b86e4 100644 --- a/src/pubkey.h +++ b/src/pubkey.h @@ -9,6 +9,7 @@ #include <hash.h> #include <serialize.h> +#include <span.h> #include <uint256.h> #include <stdexcept> @@ -169,7 +170,7 @@ public: /* * Check syntactic correctness. * - * Note that this is consensus critical as CheckSig() calls it! + * Note that this is consensus critical as CheckECDSASignature() calls it! */ bool IsValid() const { @@ -206,6 +207,27 @@ public: bool Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChild, const ChainCode& cc) const; }; +class XOnlyPubKey +{ +private: + uint256 m_keydata; + +public: + /** Construct an x-only pubkey from exactly 32 bytes. */ + XOnlyPubKey(Span<const unsigned char> bytes); + + /** Verify a Schnorr signature against this public key. + * + * sigbytes must be exactly 64 bytes. + */ + bool VerifySchnorr(const uint256& msg, Span<const unsigned char> sigbytes) const; + bool CheckPayToContract(const XOnlyPubKey& base, const uint256& hash, bool parity) const; + + const unsigned char& operator[](int pos) const { return *(m_keydata.begin() + pos); } + const unsigned char* data() const { return m_keydata.begin(); } + size_t size() const { return m_keydata.size(); } +}; + struct CExtPubKey { unsigned char nDepth; unsigned char vchFingerprint[4]; diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp index 1fbddc1ceb..a162c1ee70 100644 --- a/src/rpc/blockchain.cpp +++ b/src/rpc/blockchain.cpp @@ -1354,6 +1354,7 @@ RPCHelpMan getblockchaininfo() BuriedForkDescPushBack(softforks, "csv", consensusParams.CSVHeight); BuriedForkDescPushBack(softforks, "segwit", consensusParams.SegwitHeight); BIP9SoftForkDescPushBack(softforks, "testdummy", consensusParams, Consensus::DEPLOYMENT_TESTDUMMY); + BIP9SoftForkDescPushBack(softforks, "taproot", consensusParams, Consensus::DEPLOYMENT_TAPROOT); obj.pushKV("softforks", softforks); obj.pushKV("warnings", GetWarnings(false).original); diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index 50a6192476..5735e7df66 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -342,13 +342,10 @@ public: }; } -/** Helper for OP_CHECKSIG and OP_CHECKSIGVERIFY - * - * A return value of false means the script fails entirely. When true is returned, the - * fSuccess variable indicates whether the signature check itself succeeded. - */ -static bool EvalChecksig(const valtype& vchSig, const valtype& vchPubKey, CScript::const_iterator pbegincodehash, CScript::const_iterator pend, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror, bool& fSuccess) +static bool EvalChecksigPreTapscript(const valtype& vchSig, const valtype& vchPubKey, CScript::const_iterator pbegincodehash, CScript::const_iterator pend, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror, bool& fSuccess) { + assert(sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0); + // Subset of script starting at the most recent codeseparator CScript scriptCode(pbegincodehash, pend); @@ -363,7 +360,7 @@ static bool EvalChecksig(const valtype& vchSig, const valtype& vchPubKey, CScrip //serror is set return false; } - fSuccess = checker.CheckSig(vchSig, vchPubKey, scriptCode, sigversion); + fSuccess = checker.CheckECDSASignature(vchSig, vchPubKey, scriptCode, sigversion); if (!fSuccess && (flags & SCRIPT_VERIFY_NULLFAIL) && vchSig.size()) return set_error(serror, SCRIPT_ERR_SIG_NULLFAIL); @@ -371,7 +368,67 @@ static bool EvalChecksig(const valtype& vchSig, const valtype& vchPubKey, CScrip return true; } -bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror) +static bool EvalChecksigTapscript(const valtype& sig, const valtype& pubkey, ScriptExecutionData& execdata, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror, bool& success) +{ + assert(sigversion == SigVersion::TAPSCRIPT); + + /* + * The following validation sequence is consensus critical. Please note how -- + * upgradable public key versions precede other rules; + * the script execution fails when using empty signature with invalid public key; + * the script execution fails when using non-empty invalid signature. + */ + success = !sig.empty(); + if (success) { + // Implement the sigops/witnesssize ratio test. + // Passing with an upgradable public key version is also counted. + assert(execdata.m_validation_weight_left_init); + execdata.m_validation_weight_left -= VALIDATION_WEIGHT_PER_SIGOP_PASSED; + if (execdata.m_validation_weight_left < 0) { + return set_error(serror, SCRIPT_ERR_TAPSCRIPT_VALIDATION_WEIGHT); + } + } + if (pubkey.size() == 0) { + return set_error(serror, SCRIPT_ERR_PUBKEYTYPE); + } else if (pubkey.size() == 32) { + if (success && !checker.CheckSchnorrSignature(sig, pubkey, sigversion, execdata, serror)) { + return false; // serror is set + } + } else { + /* + * New public key version softforks should be defined before this `else` block. + * Generally, the new code should not do anything but failing the script execution. To avoid + * consensus bugs, it should not modify any existing values (including `success`). + */ + if ((flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_PUBKEYTYPE) != 0) { + return set_error(serror, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_PUBKEYTYPE); + } + } + + return true; +} + +/** Helper for OP_CHECKSIG, OP_CHECKSIGVERIFY, and (in Tapscript) OP_CHECKSIGADD. + * + * A return value of false means the script fails entirely. When true is returned, the + * success variable indicates whether the signature check itself succeeded. + */ +static bool EvalChecksig(const valtype& sig, const valtype& pubkey, CScript::const_iterator pbegincodehash, CScript::const_iterator pend, ScriptExecutionData& execdata, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror, bool& success) +{ + switch (sigversion) { + case SigVersion::BASE: + case SigVersion::WITNESS_V0: + return EvalChecksigPreTapscript(sig, pubkey, pbegincodehash, pend, flags, checker, sigversion, serror, success); + case SigVersion::TAPSCRIPT: + return EvalChecksigTapscript(sig, pubkey, execdata, flags, checker, sigversion, serror, success); + case SigVersion::TAPROOT: + // Key path spending in Taproot has no script, so this is unreachable. + break; + } + assert(false); +} + +bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptExecutionData& execdata, ScriptError* serror) { static const CScriptNum bnZero(0); static const CScriptNum bnOne(1); @@ -381,6 +438,9 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& // static const valtype vchZero(0); static const valtype vchTrue(1, 1); + // sigversion cannot be TAPROOT here, as it admits no script execution. + assert(sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0 || sigversion == SigVersion::TAPSCRIPT); + CScript::const_iterator pc = script.begin(); CScript::const_iterator pend = script.end(); CScript::const_iterator pbegincodehash = script.begin(); @@ -389,15 +449,18 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& ConditionStack vfExec; std::vector<valtype> altstack; set_error(serror, SCRIPT_ERR_UNKNOWN_ERROR); - if (script.size() > MAX_SCRIPT_SIZE) + if ((sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0) && script.size() > MAX_SCRIPT_SIZE) { return set_error(serror, SCRIPT_ERR_SCRIPT_SIZE); + } int nOpCount = 0; bool fRequireMinimal = (flags & SCRIPT_VERIFY_MINIMALDATA) != 0; + uint32_t opcode_pos = 0; + execdata.m_codeseparator_pos = 0xFFFFFFFFUL; + execdata.m_codeseparator_pos_init = true; try { - while (pc < pend) - { + for (; pc < pend; ++opcode_pos) { bool fExec = vfExec.all_true(); // @@ -408,9 +471,12 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& if (vchPushValue.size() > MAX_SCRIPT_ELEMENT_SIZE) return set_error(serror, SCRIPT_ERR_PUSH_SIZE); - // Note how OP_RESERVED does not count towards the opcode limit. - if (opcode > OP_16 && ++nOpCount > MAX_OPS_PER_SCRIPT) - return set_error(serror, SCRIPT_ERR_OP_COUNT); + if (sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0) { + // Note how OP_RESERVED does not count towards the opcode limit. + if (opcode > OP_16 && ++nOpCount > MAX_OPS_PER_SCRIPT) { + return set_error(serror, SCRIPT_ERR_OP_COUNT); + } + } if (opcode == OP_CAT || opcode == OP_SUBSTR || @@ -568,6 +634,15 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& if (stack.size() < 1) return set_error(serror, SCRIPT_ERR_UNBALANCED_CONDITIONAL); valtype& vch = stacktop(-1); + // Tapscript requires minimal IF/NOTIF inputs as a consensus rule. + if (sigversion == SigVersion::TAPSCRIPT) { + // The input argument to the OP_IF and OP_NOTIF opcodes must be either + // exactly 0 (the empty vector) or exactly 1 (the one-byte vector with value 1). + if (vch.size() > 1 || (vch.size() == 1 && vch[0] != 1)) { + return set_error(serror, SCRIPT_ERR_TAPSCRIPT_MINIMALIF); + } + } + // Under witness v0 rules it is only a policy rule, enabled through SCRIPT_VERIFY_MINIMALIF. if (sigversion == SigVersion::WITNESS_V0 && (flags & SCRIPT_VERIFY_MINIMALIF)) { if (vch.size() > 1) return set_error(serror, SCRIPT_ERR_MINIMALIF); @@ -1001,6 +1076,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& // Hash starts after the code separator pbegincodehash = pc; + execdata.m_codeseparator_pos = opcode_pos; } break; @@ -1015,7 +1091,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& valtype& vchPubKey = stacktop(-1); bool fSuccess = true; - if (!EvalChecksig(vchSig, vchPubKey, pbegincodehash, pend, flags, checker, sigversion, serror, fSuccess)) return false; + if (!EvalChecksig(vchSig, vchPubKey, pbegincodehash, pend, execdata, flags, checker, sigversion, serror, fSuccess)) return false; popstack(stack); popstack(stack); stack.push_back(fSuccess ? vchTrue : vchFalse); @@ -1029,9 +1105,32 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& } break; + case OP_CHECKSIGADD: + { + // OP_CHECKSIGADD is only available in Tapscript + if (sigversion == SigVersion::BASE || sigversion == SigVersion::WITNESS_V0) return set_error(serror, SCRIPT_ERR_BAD_OPCODE); + + // (sig num pubkey -- num) + if (stack.size() < 3) return set_error(serror, SCRIPT_ERR_INVALID_STACK_OPERATION); + + const valtype& sig = stacktop(-3); + const CScriptNum num(stacktop(-2), fRequireMinimal); + const valtype& pubkey = stacktop(-1); + + bool success = true; + if (!EvalChecksig(sig, pubkey, pbegincodehash, pend, execdata, flags, checker, sigversion, serror, success)) return false; + popstack(stack); + popstack(stack); + popstack(stack); + stack.push_back((num + (success ? 1 : 0)).getvch()); + } + break; + case OP_CHECKMULTISIG: case OP_CHECKMULTISIGVERIFY: { + if (sigversion == SigVersion::TAPSCRIPT) return set_error(serror, SCRIPT_ERR_TAPSCRIPT_CHECKMULTISIG); + // ([sig ...] num_of_signatures [pubkey ...] num_of_pubkeys -- bool) int i = 1; @@ -1089,7 +1188,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& } // Check signature - bool fOk = checker.CheckSig(vchSig, vchPubKey, scriptCode, sigversion); + bool fOk = checker.CheckECDSASignature(vchSig, vchPubKey, scriptCode, sigversion); if (fOk) { isig++; @@ -1159,6 +1258,12 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& return set_success(serror); } +bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror) +{ + ScriptExecutionData execdata; + return EvalScript(stack, script, flags, checker, sigversion, execdata, serror); +} + namespace { /** @@ -1291,35 +1396,183 @@ uint256 GetOutputsSHA256(const T& txTo) return ss.GetSHA256(); } +/** Compute the (single) SHA256 of the concatenation of all amounts spent by a tx. */ +uint256 GetSpentAmountsSHA256(const std::vector<CTxOut>& outputs_spent) +{ + CHashWriter ss(SER_GETHASH, 0); + for (const auto& txout : outputs_spent) { + ss << txout.nValue; + } + return ss.GetSHA256(); +} + +/** Compute the (single) SHA256 of the concatenation of all scriptPubKeys spent by a tx. */ +uint256 GetSpentScriptsSHA256(const std::vector<CTxOut>& outputs_spent) +{ + CHashWriter ss(SER_GETHASH, 0); + for (const auto& txout : outputs_spent) { + ss << txout.scriptPubKey; + } + return ss.GetSHA256(); +} + + } // namespace template <class T> -void PrecomputedTransactionData::Init(const T& txTo) +void PrecomputedTransactionData::Init(const T& txTo, std::vector<CTxOut>&& spent_outputs) { - assert(!m_ready); + assert(!m_spent_outputs_ready); - // Cache is calculated only for transactions with witness - if (txTo.HasWitness()) { - hashPrevouts = SHA256Uint256(GetPrevoutsSHA256(txTo)); - hashSequence = SHA256Uint256(GetSequencesSHA256(txTo)); - hashOutputs = SHA256Uint256(GetOutputsSHA256(txTo)); + m_spent_outputs = std::move(spent_outputs); + if (!m_spent_outputs.empty()) { + assert(m_spent_outputs.size() == txTo.vin.size()); + m_spent_outputs_ready = true; } - m_ready = true; + // Determine which precomputation-impacting features this transaction uses. + bool uses_bip143_segwit = false; + bool uses_bip341_taproot = false; + for (size_t inpos = 0; inpos < txTo.vin.size(); ++inpos) { + if (!txTo.vin[inpos].scriptWitness.IsNull()) { + if (m_spent_outputs_ready && m_spent_outputs[inpos].scriptPubKey.size() == 2 + WITNESS_V1_TAPROOT_SIZE && + m_spent_outputs[inpos].scriptPubKey[0] == OP_1) { + // Treat every witness-bearing spend with 34-byte scriptPubKey that starts with OP_1 as a Taproot + // spend. This only works if spent_outputs was provided as well, but if it wasn't, actual validation + // will fail anyway. Note that this branch may trigger for scriptPubKeys that aren't actually segwit + // but in that case validation will fail as SCRIPT_ERR_WITNESS_UNEXPECTED anyway. + uses_bip341_taproot = true; + } else { + // Treat every spend that's not known to native witness v1 as a Witness v0 spend. This branch may + // also be taken for unknown witness versions, but it is harmless, and being precise would require + // P2SH evaluation to find the redeemScript. + uses_bip143_segwit = true; + } + } + if (uses_bip341_taproot && uses_bip143_segwit) break; // No need to scan further if we already need all. + } + + if (uses_bip143_segwit || uses_bip341_taproot) { + // Computations shared between both sighash schemes. + m_prevouts_single_hash = GetPrevoutsSHA256(txTo); + m_sequences_single_hash = GetSequencesSHA256(txTo); + m_outputs_single_hash = GetOutputsSHA256(txTo); + } + if (uses_bip143_segwit) { + hashPrevouts = SHA256Uint256(m_prevouts_single_hash); + hashSequence = SHA256Uint256(m_sequences_single_hash); + hashOutputs = SHA256Uint256(m_outputs_single_hash); + m_bip143_segwit_ready = true; + } + if (uses_bip341_taproot) { + m_spent_amounts_single_hash = GetSpentAmountsSHA256(m_spent_outputs); + m_spent_scripts_single_hash = GetSpentScriptsSHA256(m_spent_outputs); + m_bip341_taproot_ready = true; + } } template <class T> PrecomputedTransactionData::PrecomputedTransactionData(const T& txTo) { - Init(txTo); + Init(txTo, {}); } // explicit instantiation -template void PrecomputedTransactionData::Init(const CTransaction& txTo); -template void PrecomputedTransactionData::Init(const CMutableTransaction& txTo); +template void PrecomputedTransactionData::Init(const CTransaction& txTo, std::vector<CTxOut>&& spent_outputs); +template void PrecomputedTransactionData::Init(const CMutableTransaction& txTo, std::vector<CTxOut>&& spent_outputs); template PrecomputedTransactionData::PrecomputedTransactionData(const CTransaction& txTo); template PrecomputedTransactionData::PrecomputedTransactionData(const CMutableTransaction& txTo); +static const CHashWriter HASHER_TAPSIGHASH = TaggedHash("TapSighash"); +static const CHashWriter HASHER_TAPLEAF = TaggedHash("TapLeaf"); +static const CHashWriter HASHER_TAPBRANCH = TaggedHash("TapBranch"); +static const CHashWriter HASHER_TAPTWEAK = TaggedHash("TapTweak"); + +template<typename T> +bool SignatureHashSchnorr(uint256& hash_out, const ScriptExecutionData& execdata, const T& tx_to, uint32_t in_pos, uint8_t hash_type, SigVersion sigversion, const PrecomputedTransactionData& cache) +{ + uint8_t ext_flag, key_version; + switch (sigversion) { + case SigVersion::TAPROOT: + ext_flag = 0; + // key_version is not used and left uninitialized. + break; + case SigVersion::TAPSCRIPT: + ext_flag = 1; + // key_version must be 0 for now, representing the current version of + // 32-byte public keys in the tapscript signature opcode execution. + // An upgradable public key version (with a size not 32-byte) may + // request a different key_version with a new sigversion. + key_version = 0; + break; + default: + assert(false); + } + assert(in_pos < tx_to.vin.size()); + assert(cache.m_bip341_taproot_ready && cache.m_spent_outputs_ready); + + CHashWriter ss = HASHER_TAPSIGHASH; + + // Epoch + static constexpr uint8_t EPOCH = 0; + ss << EPOCH; + + // Hash type + const uint8_t output_type = (hash_type == SIGHASH_DEFAULT) ? SIGHASH_ALL : (hash_type & SIGHASH_OUTPUT_MASK); // Default (no sighash byte) is equivalent to SIGHASH_ALL + const uint8_t input_type = hash_type & SIGHASH_INPUT_MASK; + if (!(hash_type <= 0x03 || (hash_type >= 0x81 && hash_type <= 0x83))) return false; + ss << hash_type; + + // Transaction level data + ss << tx_to.nVersion; + ss << tx_to.nLockTime; + if (input_type != SIGHASH_ANYONECANPAY) { + ss << cache.m_prevouts_single_hash; + ss << cache.m_spent_amounts_single_hash; + ss << cache.m_spent_scripts_single_hash; + ss << cache.m_sequences_single_hash; + } + if (output_type == SIGHASH_ALL) { + ss << cache.m_outputs_single_hash; + } + + // Data about the input/prevout being spent + assert(execdata.m_annex_init); + const bool have_annex = execdata.m_annex_present; + const uint8_t spend_type = (ext_flag << 1) + (have_annex ? 1 : 0); // The low bit indicates whether an annex is present. + ss << spend_type; + if (input_type == SIGHASH_ANYONECANPAY) { + ss << tx_to.vin[in_pos].prevout; + ss << cache.m_spent_outputs[in_pos]; + ss << tx_to.vin[in_pos].nSequence; + } else { + ss << in_pos; + } + if (have_annex) { + ss << execdata.m_annex_hash; + } + + // Data about the output (if only one). + if (output_type == SIGHASH_SINGLE) { + if (in_pos >= tx_to.vout.size()) return false; + CHashWriter sha_single_output(SER_GETHASH, 0); + sha_single_output << tx_to.vout[in_pos]; + ss << sha_single_output.GetSHA256(); + } + + // Additional data for BIP 342 signatures + if (sigversion == SigVersion::TAPSCRIPT) { + assert(execdata.m_tapleaf_hash_init); + ss << execdata.m_tapleaf_hash; + ss << key_version; + assert(execdata.m_codeseparator_pos_init); + ss << execdata.m_codeseparator_pos; + } + + hash_out = ss.GetSHA256(); + return true; +} + template <class T> uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion, const PrecomputedTransactionData* cache) { @@ -1329,7 +1582,7 @@ uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn uint256 hashPrevouts; uint256 hashSequence; uint256 hashOutputs; - const bool cacheready = cache && cache->m_ready; + const bool cacheready = cache && cache->m_bip143_segwit_ready; if (!(nHashType & SIGHASH_ANYONECANPAY)) { hashPrevouts = cacheready ? cache->hashPrevouts : SHA256Uint256(GetPrevoutsSHA256(txTo)); @@ -1389,13 +1642,19 @@ uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn } template <class T> -bool GenericTransactionSignatureChecker<T>::VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& pubkey, const uint256& sighash) const +bool GenericTransactionSignatureChecker<T>::VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& pubkey, const uint256& sighash) const { return pubkey.Verify(sighash, vchSig); } template <class T> -bool GenericTransactionSignatureChecker<T>::CheckSig(const std::vector<unsigned char>& vchSigIn, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const +bool GenericTransactionSignatureChecker<T>::VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const +{ + return pubkey.VerifySchnorr(sighash, sig); +} + +template <class T> +bool GenericTransactionSignatureChecker<T>::CheckECDSASignature(const std::vector<unsigned char>& vchSigIn, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const { CPubKey pubkey(vchPubKey); if (!pubkey.IsValid()) @@ -1410,13 +1669,41 @@ bool GenericTransactionSignatureChecker<T>::CheckSig(const std::vector<unsigned uint256 sighash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, sigversion, this->txdata); - if (!VerifySignature(vchSig, pubkey, sighash)) + if (!VerifyECDSASignature(vchSig, pubkey, sighash)) return false; return true; } template <class T> +bool GenericTransactionSignatureChecker<T>::CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey_in, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror) const +{ + assert(sigversion == SigVersion::TAPROOT || sigversion == SigVersion::TAPSCRIPT); + // Schnorr signatures have 32-byte public keys. The caller is responsible for enforcing this. + assert(pubkey_in.size() == 32); + // Note that in Tapscript evaluation, empty signatures are treated specially (invalid signature that does not + // abort script execution). This is implemented in EvalChecksigTapscript, which won't invoke + // CheckSchnorrSignature in that case. In other contexts, they are invalid like every other signature with + // size different from 64 or 65. + if (sig.size() != 64 && sig.size() != 65) return set_error(serror, SCRIPT_ERR_SCHNORR_SIG_SIZE); + + XOnlyPubKey pubkey{pubkey_in}; + + uint8_t hashtype = SIGHASH_DEFAULT; + if (sig.size() == 65) { + hashtype = SpanPopBack(sig); + if (hashtype == SIGHASH_DEFAULT) return set_error(serror, SCRIPT_ERR_SCHNORR_SIG_HASHTYPE); + } + uint256 sighash; + assert(this->txdata); + if (!SignatureHashSchnorr(sighash, execdata, *txTo, nIn, hashtype, sigversion, *this->txdata)) { + return set_error(serror, SCRIPT_ERR_SCHNORR_SIG_HASHTYPE); + } + if (!VerifySchnorrSignature(sig, pubkey, sighash)) return set_error(serror, SCRIPT_ERR_SCHNORR_SIG); + return true; +} + +template <class T> bool GenericTransactionSignatureChecker<T>::CheckLockTime(const CScriptNum& nLockTime) const { // There are two kinds of nLockTime: lock-by-blockheight @@ -1504,17 +1791,39 @@ bool GenericTransactionSignatureChecker<T>::CheckSequence(const CScriptNum& nSeq template class GenericTransactionSignatureChecker<CTransaction>; template class GenericTransactionSignatureChecker<CMutableTransaction>; -static bool ExecuteWitnessScript(const Span<const valtype>& stack_span, const CScript& scriptPubKey, unsigned int flags, SigVersion sigversion, const BaseSignatureChecker& checker, ScriptError* serror) +static bool ExecuteWitnessScript(const Span<const valtype>& stack_span, const CScript& scriptPubKey, unsigned int flags, SigVersion sigversion, const BaseSignatureChecker& checker, ScriptExecutionData& execdata, ScriptError* serror) { std::vector<valtype> stack{stack_span.begin(), stack_span.end()}; + if (sigversion == SigVersion::TAPSCRIPT) { + // OP_SUCCESSx processing overrides everything, including stack element size limits + CScript::const_iterator pc = scriptPubKey.begin(); + while (pc < scriptPubKey.end()) { + opcodetype opcode; + if (!scriptPubKey.GetOp(pc, opcode)) { + // Note how this condition would not be reached if an unknown OP_SUCCESSx was found + return set_error(serror, SCRIPT_ERR_BAD_OPCODE); + } + // New opcodes will be listed here. May use a different sigversion to modify existing opcodes. + if (IsOpSuccess(opcode)) { + if (flags & SCRIPT_VERIFY_DISCOURAGE_OP_SUCCESS) { + return set_error(serror, SCRIPT_ERR_DISCOURAGE_OP_SUCCESS); + } + return set_success(serror); + } + } + + // Tapscript enforces initial stack size limits (altstack is empty here) + if (stack.size() > MAX_STACK_SIZE) return set_error(serror, SCRIPT_ERR_STACK_SIZE); + } + // Disallow stack item size > MAX_SCRIPT_ELEMENT_SIZE in witness stack for (const valtype& elem : stack) { if (elem.size() > MAX_SCRIPT_ELEMENT_SIZE) return set_error(serror, SCRIPT_ERR_PUSH_SIZE); } // Run the script interpreter. - if (!EvalScript(stack, scriptPubKey, flags, checker, sigversion, serror)) return false; + if (!EvalScript(stack, scriptPubKey, flags, checker, sigversion, execdata, serror)) return false; // Scripts inside witness implicitly require cleanstack behaviour if (stack.size() != 1) return set_error(serror, SCRIPT_ERR_CLEANSTACK); @@ -1522,40 +1831,104 @@ static bool ExecuteWitnessScript(const Span<const valtype>& stack_span, const CS return true; } -static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion, const std::vector<unsigned char>& program, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror) +static bool VerifyTaprootCommitment(const std::vector<unsigned char>& control, const std::vector<unsigned char>& program, const CScript& script, uint256& tapleaf_hash) { - CScript scriptPubKey; + const int path_len = (control.size() - TAPROOT_CONTROL_BASE_SIZE) / TAPROOT_CONTROL_NODE_SIZE; + const XOnlyPubKey p{uint256(std::vector<unsigned char>(control.begin() + 1, control.begin() + TAPROOT_CONTROL_BASE_SIZE))}; + const XOnlyPubKey q{uint256(program)}; + tapleaf_hash = (CHashWriter(HASHER_TAPLEAF) << uint8_t(control[0] & TAPROOT_LEAF_MASK) << script).GetSHA256(); + uint256 k = tapleaf_hash; + for (int i = 0; i < path_len; ++i) { + CHashWriter ss_branch{HASHER_TAPBRANCH}; + Span<const unsigned char> node(control.data() + TAPROOT_CONTROL_BASE_SIZE + TAPROOT_CONTROL_NODE_SIZE * i, TAPROOT_CONTROL_NODE_SIZE); + if (std::lexicographical_compare(k.begin(), k.end(), node.begin(), node.end())) { + ss_branch << k << node; + } else { + ss_branch << node << k; + } + k = ss_branch.GetSHA256(); + } + k = (CHashWriter(HASHER_TAPTWEAK) << MakeSpan(p) << k).GetSHA256(); + return q.CheckPayToContract(p, k, control[0] & 1); +} + +static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion, const std::vector<unsigned char>& program, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror, bool is_p2sh) +{ + CScript exec_script; //!< Actually executed script (last stack item in P2WSH; implied P2PKH script in P2WPKH; leaf script in P2TR) Span<const valtype> stack{witness.stack}; + ScriptExecutionData execdata; if (witversion == 0) { if (program.size() == WITNESS_V0_SCRIPTHASH_SIZE) { - // Version 0 segregated witness program: SHA256(CScript) inside the program, CScript + inputs in witness + // BIP141 P2WSH: 32-byte witness v0 program (which encodes SHA256(script)) if (stack.size() == 0) { return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_WITNESS_EMPTY); } const valtype& script_bytes = SpanPopBack(stack); - scriptPubKey = CScript(script_bytes.begin(), script_bytes.end()); - uint256 hashScriptPubKey; - CSHA256().Write(&scriptPubKey[0], scriptPubKey.size()).Finalize(hashScriptPubKey.begin()); - if (memcmp(hashScriptPubKey.begin(), program.data(), 32)) { + exec_script = CScript(script_bytes.begin(), script_bytes.end()); + uint256 hash_exec_script; + CSHA256().Write(&exec_script[0], exec_script.size()).Finalize(hash_exec_script.begin()); + if (memcmp(hash_exec_script.begin(), program.data(), 32)) { return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH); } - return ExecuteWitnessScript(stack, scriptPubKey, flags, SigVersion::WITNESS_V0, checker, serror); + return ExecuteWitnessScript(stack, exec_script, flags, SigVersion::WITNESS_V0, checker, execdata, serror); } else if (program.size() == WITNESS_V0_KEYHASH_SIZE) { - // Special case for pay-to-pubkeyhash; signature + pubkey in witness + // BIP141 P2WPKH: 20-byte witness v0 program (which encodes Hash160(pubkey)) if (stack.size() != 2) { return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH); // 2 items in witness } - scriptPubKey << OP_DUP << OP_HASH160 << program << OP_EQUALVERIFY << OP_CHECKSIG; - return ExecuteWitnessScript(stack, scriptPubKey, flags, SigVersion::WITNESS_V0, checker, serror); + exec_script << OP_DUP << OP_HASH160 << program << OP_EQUALVERIFY << OP_CHECKSIG; + return ExecuteWitnessScript(stack, exec_script, flags, SigVersion::WITNESS_V0, checker, execdata, serror); } else { return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_WRONG_LENGTH); } + } else if (witversion == 1 && program.size() == WITNESS_V1_TAPROOT_SIZE && !is_p2sh) { + // BIP341 Taproot: 32-byte non-P2SH witness v1 program (which encodes a P2C-tweaked pubkey) + if (!(flags & SCRIPT_VERIFY_TAPROOT)) return set_success(serror); + if (stack.size() == 0) return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_WITNESS_EMPTY); + if (stack.size() >= 2 && !stack.back().empty() && stack.back()[0] == ANNEX_TAG) { + // Drop annex (this is non-standard; see IsWitnessStandard) + const valtype& annex = SpanPopBack(stack); + execdata.m_annex_hash = (CHashWriter(SER_GETHASH, 0) << annex).GetSHA256(); + execdata.m_annex_present = true; + } else { + execdata.m_annex_present = false; + } + execdata.m_annex_init = true; + if (stack.size() == 1) { + // Key path spending (stack size is 1 after removing optional annex) + if (!checker.CheckSchnorrSignature(stack.front(), program, SigVersion::TAPROOT, execdata, serror)) { + return false; // serror is set + } + return set_success(serror); + } else { + // Script path spending (stack size is >1 after removing optional annex) + const valtype& control = SpanPopBack(stack); + const valtype& script_bytes = SpanPopBack(stack); + exec_script = CScript(script_bytes.begin(), script_bytes.end()); + if (control.size() < TAPROOT_CONTROL_BASE_SIZE || control.size() > TAPROOT_CONTROL_MAX_SIZE || ((control.size() - TAPROOT_CONTROL_BASE_SIZE) % TAPROOT_CONTROL_NODE_SIZE) != 0) { + return set_error(serror, SCRIPT_ERR_TAPROOT_WRONG_CONTROL_SIZE); + } + if (!VerifyTaprootCommitment(control, program, exec_script, execdata.m_tapleaf_hash)) { + return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH); + } + execdata.m_tapleaf_hash_init = true; + if ((control[0] & TAPROOT_LEAF_MASK) == TAPROOT_LEAF_TAPSCRIPT) { + // Tapscript (leaf version 0xc0) + execdata.m_validation_weight_left = ::GetSerializeSize(witness.stack, PROTOCOL_VERSION) + VALIDATION_WEIGHT_OFFSET; + execdata.m_validation_weight_left_init = true; + return ExecuteWitnessScript(stack, exec_script, flags, SigVersion::TAPSCRIPT, checker, execdata, serror); + } + if (flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION) { + return set_error(serror, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION); + } + return set_success(serror); + } } else { if (flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM) { return set_error(serror, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM); } - // Higher version witness scripts return true for future softfork compatibility + // Other version/size/p2sh combinations return true for future softfork compatibility return true; } // There is intentionally no return statement here, to be able to use "control reaches end of non-void function" warnings to detect gaps in the logic above. @@ -1601,7 +1974,7 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C // The scriptSig must be _exactly_ CScript(), otherwise we reintroduce malleability. return set_error(serror, SCRIPT_ERR_WITNESS_MALLEATED); } - if (!VerifyWitnessProgram(*witness, witnessversion, witnessprogram, flags, checker, serror)) { + if (!VerifyWitnessProgram(*witness, witnessversion, witnessprogram, flags, checker, serror, /* is_p2sh */ false)) { return false; } // Bypass the cleanstack check at the end. The actual stack is obviously not clean @@ -1646,7 +2019,7 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C // reintroduce malleability. return set_error(serror, SCRIPT_ERR_WITNESS_MALLEATED_P2SH); } - if (!VerifyWitnessProgram(*witness, witnessversion, witnessprogram, flags, checker, serror)) { + if (!VerifyWitnessProgram(*witness, witnessversion, witnessprogram, flags, checker, serror, /* is_p2sh */ true)) { return false; } // Bypass the cleanstack check at the end. The actual stack is obviously not clean diff --git a/src/script/interpreter.h b/src/script/interpreter.h index 71f2436369..c0c2b012c6 100644 --- a/src/script/interpreter.h +++ b/src/script/interpreter.h @@ -7,14 +7,17 @@ #define BITCOIN_SCRIPT_INTERPRETER_H #include <script/script_error.h> +#include <span.h> #include <primitives/transaction.h> #include <vector> #include <stdint.h> class CPubKey; +class XOnlyPubKey; class CScript; class CTransaction; +class CTxOut; class uint256; /** Signature hash types/flags */ @@ -24,6 +27,10 @@ enum SIGHASH_NONE = 2, SIGHASH_SINGLE = 3, SIGHASH_ANYONECANPAY = 0x80, + + SIGHASH_DEFAULT = 0, //!< Taproot only; implied when sighash byte is missing, and equivalent to SIGHASH_ALL + SIGHASH_OUTPUT_MASK = 3, + SIGHASH_INPUT_MASK = 0x80, }; /** Script verification flags. @@ -79,6 +86,8 @@ enum // "Exactly one stack element must remain, and when interpreted as a boolean, it must be true". // (BIP62 rule 6) // Note: CLEANSTACK should never be used without P2SH or WITNESS. + // Note: WITNESS_V0 and TAPSCRIPT script execution have behavior similar to CLEANSTACK as part of their + // consensus rules. It is automatic there and does not need this flag. SCRIPT_VERIFY_CLEANSTACK = (1U << 8), // Verify CHECKLOCKTIMEVERIFY @@ -101,6 +110,8 @@ enum // Segwit script only: Require the argument of OP_IF/NOTIF to be exactly 0x01 or empty vector // + // Note: TAPSCRIPT script execution has behavior similar to MINIMALIF as part of its consensus + // rules. It is automatic there and does not depend on this flag. SCRIPT_VERIFY_MINIMALIF = (1U << 13), // Signature(s) must be empty vector if a CHECK(MULTI)SIG operation failed @@ -114,19 +125,49 @@ enum // Making OP_CODESEPARATOR and FindAndDelete fail any non-segwit scripts // SCRIPT_VERIFY_CONST_SCRIPTCODE = (1U << 16), + + // Taproot/Tapscript validation (BIPs 341 & 342) + // + SCRIPT_VERIFY_TAPROOT = (1U << 17), + + // Making unknown Taproot leaf versions non-standard + // + SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION = (1U << 18), + + // Making unknown OP_SUCCESS non-standard + SCRIPT_VERIFY_DISCOURAGE_OP_SUCCESS = (1U << 19), + + // Making unknown public key versions (in BIP 342 scripts) non-standard + SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_PUBKEYTYPE = (1U << 20), }; bool CheckSignatureEncoding(const std::vector<unsigned char> &vchSig, unsigned int flags, ScriptError* serror); struct PrecomputedTransactionData { + // BIP341 precomputed data. + // These are single-SHA256, see https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki#cite_note-15. + uint256 m_prevouts_single_hash; + uint256 m_sequences_single_hash; + uint256 m_outputs_single_hash; + uint256 m_spent_amounts_single_hash; + uint256 m_spent_scripts_single_hash; + //! Whether the 5 fields above are initialized. + bool m_bip341_taproot_ready = false; + + // BIP143 precomputed data (double-SHA256). uint256 hashPrevouts, hashSequence, hashOutputs; - bool m_ready = false; + //! Whether the 3 fields above are initialized. + bool m_bip143_segwit_ready = false; + + std::vector<CTxOut> m_spent_outputs; + //! Whether m_spent_outputs is initialized. + bool m_spent_outputs_ready = false; PrecomputedTransactionData() = default; template <class T> - void Init(const T& tx); + void Init(const T& tx, std::vector<CTxOut>&& spent_outputs); template <class T> explicit PrecomputedTransactionData(const T& tx); @@ -134,13 +175,48 @@ struct PrecomputedTransactionData enum class SigVersion { - BASE = 0, - WITNESS_V0 = 1, + BASE = 0, //!< Bare scripts and BIP16 P2SH-wrapped redeemscripts + WITNESS_V0 = 1, //!< Witness v0 (P2WPKH and P2WSH); see BIP 141 + TAPROOT = 2, //!< Witness v1 with 32-byte program, not BIP16 P2SH-wrapped, key path spending; see BIP 341 + TAPSCRIPT = 3, //!< Witness v1 with 32-byte program, not BIP16 P2SH-wrapped, script path spending, leaf version 0xc0; see BIP 342 +}; + +struct ScriptExecutionData +{ + //! Whether m_tapleaf_hash is initialized. + bool m_tapleaf_hash_init = false; + //! The tapleaf hash. + uint256 m_tapleaf_hash; + + //! Whether m_codeseparator_pos is initialized. + bool m_codeseparator_pos_init = false; + //! Opcode position of the last executed OP_CODESEPARATOR (or 0xFFFFFFFF if none executed). + uint32_t m_codeseparator_pos; + + //! Whether m_annex_present and (when needed) m_annex_hash are initialized. + bool m_annex_init = false; + //! Whether an annex is present. + bool m_annex_present; + //! Hash of the annex data. + uint256 m_annex_hash; + + //! Whether m_validation_weight_left is initialized. + bool m_validation_weight_left_init = false; + //! How much validation weight is left (decremented for every successful non-empty signature check). + int64_t m_validation_weight_left; }; /** Signature hash sizes */ static constexpr size_t WITNESS_V0_SCRIPTHASH_SIZE = 32; static constexpr size_t WITNESS_V0_KEYHASH_SIZE = 20; +static constexpr size_t WITNESS_V1_TAPROOT_SIZE = 32; + +static constexpr uint8_t TAPROOT_LEAF_MASK = 0xfe; +static constexpr uint8_t TAPROOT_LEAF_TAPSCRIPT = 0xc0; +static constexpr size_t TAPROOT_CONTROL_BASE_SIZE = 33; +static constexpr size_t TAPROOT_CONTROL_NODE_SIZE = 32; +static constexpr size_t TAPROOT_CONTROL_MAX_NODE_COUNT = 128; +static constexpr size_t TAPROOT_CONTROL_MAX_SIZE = TAPROOT_CONTROL_BASE_SIZE + TAPROOT_CONTROL_NODE_SIZE * TAPROOT_CONTROL_MAX_NODE_COUNT; template <class T> uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn, int nHashType, const CAmount& amount, SigVersion sigversion, const PrecomputedTransactionData* cache = nullptr); @@ -148,7 +224,12 @@ uint256 SignatureHash(const CScript& scriptCode, const T& txTo, unsigned int nIn class BaseSignatureChecker { public: - virtual bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const + virtual bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const + { + return false; + } + + virtual bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror = nullptr) const { return false; } @@ -176,12 +257,14 @@ private: const PrecomputedTransactionData* txdata; protected: - virtual bool VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const; + virtual bool VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const; + virtual bool VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const; public: GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(nullptr) {} GenericTransactionSignatureChecker(const T* txToIn, unsigned int nInIn, const CAmount& amountIn, const PrecomputedTransactionData& txdataIn) : txTo(txToIn), nIn(nInIn), amount(amountIn), txdata(&txdataIn) {} - bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override; + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override; + bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror = nullptr) const override; bool CheckLockTime(const CScriptNum& nLockTime) const override; bool CheckSequence(const CScriptNum& nSequence) const override; }; @@ -189,6 +272,7 @@ public: using TransactionSignatureChecker = GenericTransactionSignatureChecker<CTransaction>; using MutableTransactionSignatureChecker = GenericTransactionSignatureChecker<CMutableTransaction>; +bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptExecutionData& execdata, ScriptError* error = nullptr); bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* error = nullptr); bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CScriptWitness* witness, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror = nullptr); diff --git a/src/script/script.cpp b/src/script/script.cpp index 92c6fe7785..f31472e42d 100644 --- a/src/script/script.cpp +++ b/src/script/script.cpp @@ -140,6 +140,9 @@ std::string GetOpName(opcodetype opcode) case OP_NOP9 : return "OP_NOP9"; case OP_NOP10 : return "OP_NOP10"; + // Opcode added by BIP 342 (Tapscript) + case OP_CHECKSIGADD : return "OP_CHECKSIGADD"; + case OP_INVALIDOPCODE : return "OP_INVALIDOPCODE"; default: @@ -328,3 +331,11 @@ bool GetScriptOp(CScriptBase::const_iterator& pc, CScriptBase::const_iterator en opcodeRet = static_cast<opcodetype>(opcode); return true; } + +bool IsOpSuccess(const opcodetype& opcode) +{ + return opcode == 80 || opcode == 98 || (opcode >= 126 && opcode <= 129) || + (opcode >= 131 && opcode <= 134) || (opcode >= 137 && opcode <= 138) || + (opcode >= 141 && opcode <= 142) || (opcode >= 149 && opcode <= 153) || + (opcode >= 187 && opcode <= 254); +} diff --git a/src/script/script.h b/src/script/script.h index c1f2b66921..974cde4984 100644 --- a/src/script/script.h +++ b/src/script/script.h @@ -44,6 +44,17 @@ static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov 5 00:53:20 // SEQUENCE_FINAL). static const uint32_t LOCKTIME_MAX = 0xFFFFFFFFU; +// Tag for input annex. If there are at least two witness elements for a transaction input, +// and the first byte of the last element is 0x50, this last element is called annex, and +// has meanings independent of the script +static constexpr unsigned int ANNEX_TAG = 0x50; + +// Validation weight per passing signature (Tapscript only, see BIP 342). +static constexpr uint64_t VALIDATION_WEIGHT_PER_SIGOP_PASSED = 50; + +// How much weight budget is added to the witness size (Tapscript only, see BIP 342). +static constexpr uint64_t VALIDATION_WEIGHT_OFFSET = 50; + template <typename T> std::vector<unsigned char> ToByteVector(const T& in) { @@ -187,6 +198,9 @@ enum opcodetype OP_NOP9 = 0xb8, OP_NOP10 = 0xb9, + // Opcode added by BIP 342 (Tapscript) + OP_CHECKSIGADD = 0xba, + OP_INVALIDOPCODE = 0xff, }; @@ -555,4 +569,7 @@ struct CScriptWitness std::string ToString() const; }; +/** Test for OP_SUCCESSx opcodes as defined by BIP342. */ +bool IsOpSuccess(const opcodetype& opcode); + #endif // BITCOIN_SCRIPT_SCRIPT_H diff --git a/src/script/script_error.cpp b/src/script/script_error.cpp index 3b383393f9..fadc04262c 100644 --- a/src/script/script_error.cpp +++ b/src/script/script_error.cpp @@ -73,6 +73,12 @@ std::string ScriptErrorString(const ScriptError serror) return "NOPx reserved for soft-fork upgrades"; case SCRIPT_ERR_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM: return "Witness version reserved for soft-fork upgrades"; + case SCRIPT_ERR_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION: + return "Taproot version reserved for soft-fork upgrades"; + case SCRIPT_ERR_DISCOURAGE_OP_SUCCESS: + return "OP_SUCCESSx reserved for soft-fork upgrades"; + case SCRIPT_ERR_DISCOURAGE_UPGRADABLE_PUBKEYTYPE: + return "Public key version reserved for soft-fork upgrades"; case SCRIPT_ERR_PUBKEYTYPE: return "Public key is neither compressed or uncompressed"; case SCRIPT_ERR_CLEANSTACK: @@ -91,6 +97,20 @@ std::string ScriptErrorString(const ScriptError serror) return "Witness provided for non-witness script"; case SCRIPT_ERR_WITNESS_PUBKEYTYPE: return "Using non-compressed keys in segwit"; + case SCRIPT_ERR_SCHNORR_SIG_SIZE: + return "Invalid Schnorr signature size"; + case SCRIPT_ERR_SCHNORR_SIG_HASHTYPE: + return "Invalid Schnorr signature hash type"; + case SCRIPT_ERR_SCHNORR_SIG: + return "Invalid Schnorr signature"; + case SCRIPT_ERR_TAPROOT_WRONG_CONTROL_SIZE: + return "Invalid Taproot control block size"; + case SCRIPT_ERR_TAPSCRIPT_VALIDATION_WEIGHT: + return "Too much signature validation relative to witness weight"; + case SCRIPT_ERR_TAPSCRIPT_CHECKMULTISIG: + return "OP_CHECKMULTISIG(VERIFY) is not available in tapscript"; + case SCRIPT_ERR_TAPSCRIPT_MINIMALIF: + return "OP_IF/NOTIF argument must be minimal in tapscript"; case SCRIPT_ERR_OP_CODESEPARATOR: return "Using OP_CODESEPARATOR in non-witness script"; case SCRIPT_ERR_SIG_FINDANDDELETE: diff --git a/src/script/script_error.h b/src/script/script_error.h index 2978c147e1..b071681613 100644 --- a/src/script/script_error.h +++ b/src/script/script_error.h @@ -56,6 +56,9 @@ typedef enum ScriptError_t /* softfork safeness */ SCRIPT_ERR_DISCOURAGE_UPGRADABLE_NOPS, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM, + SCRIPT_ERR_DISCOURAGE_UPGRADABLE_TAPROOT_VERSION, + SCRIPT_ERR_DISCOURAGE_OP_SUCCESS, + SCRIPT_ERR_DISCOURAGE_UPGRADABLE_PUBKEYTYPE, /* segregated witness */ SCRIPT_ERR_WITNESS_PROGRAM_WRONG_LENGTH, @@ -66,6 +69,15 @@ typedef enum ScriptError_t SCRIPT_ERR_WITNESS_UNEXPECTED, SCRIPT_ERR_WITNESS_PUBKEYTYPE, + /* Taproot */ + SCRIPT_ERR_SCHNORR_SIG_SIZE, + SCRIPT_ERR_SCHNORR_SIG_HASHTYPE, + SCRIPT_ERR_SCHNORR_SIG, + SCRIPT_ERR_TAPROOT_WRONG_CONTROL_SIZE, + SCRIPT_ERR_TAPSCRIPT_VALIDATION_WEIGHT, + SCRIPT_ERR_TAPSCRIPT_CHECKMULTISIG, + SCRIPT_ERR_TAPSCRIPT_MINIMALIF, + /* Constant scriptCode */ SCRIPT_ERR_OP_CODESEPARATOR, SCRIPT_ERR_SIG_FINDANDDELETE, diff --git a/src/script/sigcache.cpp b/src/script/sigcache.cpp index aaecab1ef2..4a6e04f2eb 100644 --- a/src/script/sigcache.cpp +++ b/src/script/sigcache.cpp @@ -22,8 +22,9 @@ namespace { class CSignatureCache { private: - //! Entries are SHA256(nonce || signature hash || public key || signature): - CSHA256 m_salted_hasher; + //! Entries are SHA256(nonce || 'E' or 'S' || 31 zero bytes || signature hash || public key || signature): + CSHA256 m_salted_hasher_ecdsa; + CSHA256 m_salted_hasher_schnorr; typedef CuckooCache::cache<uint256, SignatureCacheHasher> map_type; map_type setValid; boost::shared_mutex cs_sigcache; @@ -34,18 +35,30 @@ public: 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. - m_salted_hasher.Write(nonce.begin(), 32); - m_salted_hasher.Write(nonce.begin(), 32); + // just write our 32-byte entropy, and then pad with 'E' for ECDSA and + // 'S' for Schnorr (followed by 0 bytes). + static constexpr unsigned char PADDING_ECDSA[32] = {'E'}; + static constexpr unsigned char PADDING_SCHNORR[32] = {'S'}; + m_salted_hasher_ecdsa.Write(nonce.begin(), 32); + m_salted_hasher_ecdsa.Write(PADDING_ECDSA, 32); + m_salted_hasher_schnorr.Write(nonce.begin(), 32); + m_salted_hasher_schnorr.Write(PADDING_SCHNORR, 32); } void - ComputeEntry(uint256& entry, const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubkey) + ComputeEntryECDSA(uint256& entry, const uint256 &hash, const std::vector<unsigned char>& vchSig, const CPubKey& pubkey) { - CSHA256 hasher = m_salted_hasher; + CSHA256 hasher = m_salted_hasher_ecdsa; hasher.Write(hash.begin(), 32).Write(&pubkey[0], pubkey.size()).Write(&vchSig[0], vchSig.size()).Finalize(entry.begin()); } + void + ComputeEntrySchnorr(uint256& entry, const uint256 &hash, Span<const unsigned char> sig, const XOnlyPubKey& pubkey) + { + CSHA256 hasher = m_salted_hasher_schnorr; + hasher.Write(hash.begin(), 32).Write(&pubkey[0], pubkey.size()).Write(sig.data(), sig.size()).Finalize(entry.begin()); + } + bool Get(const uint256& entry, const bool erase) { @@ -85,15 +98,25 @@ void InitSignatureCache() (nElems*sizeof(uint256)) >>20, (nMaxCacheSize*2)>>20, nElems); } -bool CachingTransactionSignatureChecker::VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& pubkey, const uint256& sighash) const +bool CachingTransactionSignatureChecker::VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& pubkey, const uint256& sighash) const { uint256 entry; - signatureCache.ComputeEntry(entry, sighash, vchSig, pubkey); + signatureCache.ComputeEntryECDSA(entry, sighash, vchSig, pubkey); if (signatureCache.Get(entry, !store)) return true; - if (!TransactionSignatureChecker::VerifySignature(vchSig, pubkey, sighash)) + if (!TransactionSignatureChecker::VerifyECDSASignature(vchSig, pubkey, sighash)) return false; if (store) signatureCache.Set(entry); return true; } + +bool CachingTransactionSignatureChecker::VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const +{ + uint256 entry; + signatureCache.ComputeEntrySchnorr(entry, sighash, sig, pubkey); + if (signatureCache.Get(entry, !store)) return true; + if (!TransactionSignatureChecker::VerifySchnorrSignature(sig, pubkey, sighash)) return false; + if (store) signatureCache.Set(entry); + return true; +} diff --git a/src/script/sigcache.h b/src/script/sigcache.h index 807b61b542..00534f9758 100644 --- a/src/script/sigcache.h +++ b/src/script/sigcache.h @@ -7,6 +7,7 @@ #define BITCOIN_SCRIPT_SIGCACHE_H #include <script/interpreter.h> +#include <span.h> #include <vector> @@ -48,7 +49,8 @@ private: public: CachingTransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn, const CAmount& amountIn, bool storeIn, PrecomputedTransactionData& txdataIn) : TransactionSignatureChecker(txToIn, nInIn, amountIn, txdataIn), store(storeIn) {} - bool VerifySignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const override; + bool VerifyECDSASignature(const std::vector<unsigned char>& vchSig, const CPubKey& vchPubKey, const uint256& sighash) const override; + bool VerifySchnorrSignature(Span<const unsigned char> sig, const XOnlyPubKey& pubkey, const uint256& sighash) const override; }; void InitSignatureCache(); diff --git a/src/script/sign.cpp b/src/script/sign.cpp index 9b3f94f14d..0e6864d547 100644 --- a/src/script/sign.cpp +++ b/src/script/sign.cpp @@ -111,6 +111,7 @@ static bool SignStep(const SigningProvider& provider, const BaseSignatureCreator case TxoutType::NONSTANDARD: case TxoutType::NULL_DATA: case TxoutType::WITNESS_UNKNOWN: + case TxoutType::WITNESS_V1_TAPROOT: return false; case TxoutType::PUBKEY: if (!CreateSig(creator, sigdata, provider, sig, CPubKey(vSolutions[0]), scriptPubKey, sigversion)) return false; @@ -260,9 +261,9 @@ private: public: SignatureExtractorChecker(SignatureData& sigdata, BaseSignatureChecker& checker) : sigdata(sigdata), checker(checker) {} - bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { - if (checker.CheckSig(scriptSig, vchPubKey, scriptCode, sigversion)) { + if (checker.CheckECDSASignature(scriptSig, vchPubKey, scriptCode, sigversion)) { CPubKey pubkey(vchPubKey); sigdata.signatures.emplace(pubkey.GetID(), SigPair(pubkey, scriptSig)); return true; @@ -339,7 +340,7 @@ SignatureData DataFromTransaction(const CMutableTransaction& tx, unsigned int nI for (unsigned int i = last_success_key; i < num_pubkeys; ++i) { const valtype& pubkey = solutions[i+1]; // We either have a signature for this pubkey, or we have found a signature and it is valid - if (data.signatures.count(CPubKey(pubkey).GetID()) || extractor_checker.CheckSig(sig, pubkey, next_script, sigversion)) { + if (data.signatures.count(CPubKey(pubkey).GetID()) || extractor_checker.CheckECDSASignature(sig, pubkey, next_script, sigversion)) { last_success_key = i + 1; break; } @@ -400,7 +401,7 @@ class DummySignatureChecker final : public BaseSignatureChecker { public: DummySignatureChecker() {} - bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { return true; } + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { return true; } }; const DummySignatureChecker DUMMY_CHECKER; diff --git a/src/script/sign.h b/src/script/sign.h index b77d26c0d7..a1cfe1574d 100644 --- a/src/script/sign.h +++ b/src/script/sign.h @@ -11,6 +11,7 @@ #include <pubkey.h> #include <script/interpreter.h> #include <script/keyorigin.h> +#include <span.h> #include <streams.h> class CKey; diff --git a/src/script/standard.cpp b/src/script/standard.cpp index 96a3d311a6..f2f81664f6 100644 --- a/src/script/standard.cpp +++ b/src/script/standard.cpp @@ -55,6 +55,7 @@ std::string GetTxnOutputType(TxoutType t) case TxoutType::NULL_DATA: return "nulldata"; case TxoutType::WITNESS_V0_KEYHASH: return "witness_v0_keyhash"; case TxoutType::WITNESS_V0_SCRIPTHASH: return "witness_v0_scripthash"; + case TxoutType::WITNESS_V1_TAPROOT: return "witness_v1_taproot"; case TxoutType::WITNESS_UNKNOWN: return "witness_unknown"; } // no default case, so the compiler can warn about missing cases assert(false); @@ -130,6 +131,11 @@ TxoutType Solver(const CScript& scriptPubKey, std::vector<std::vector<unsigned c vSolutionsRet.push_back(witnessprogram); return TxoutType::WITNESS_V0_SCRIPTHASH; } + if (witnessversion == 1 && witnessprogram.size() == WITNESS_V1_TAPROOT_SIZE) { + vSolutionsRet.push_back(std::vector<unsigned char>{(unsigned char)witnessversion}); + vSolutionsRet.push_back(std::move(witnessprogram)); + return TxoutType::WITNESS_V1_TAPROOT; + } if (witnessversion != 0) { vSolutionsRet.push_back(std::vector<unsigned char>{(unsigned char)witnessversion}); vSolutionsRet.push_back(std::move(witnessprogram)); @@ -203,7 +209,7 @@ bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) std::copy(vSolutions[0].begin(), vSolutions[0].end(), hash.begin()); addressRet = hash; return true; - } else if (whichType == TxoutType::WITNESS_UNKNOWN) { + } else if (whichType == TxoutType::WITNESS_UNKNOWN || whichType == TxoutType::WITNESS_V1_TAPROOT) { WitnessUnknown unk; unk.version = vSolutions[0][0]; std::copy(vSolutions[1].begin(), vSolutions[1].end(), unk.program); diff --git a/src/script/standard.h b/src/script/standard.h index 6dbcd04968..721203385e 100644 --- a/src/script/standard.h +++ b/src/script/standard.h @@ -129,6 +129,7 @@ enum class TxoutType { NULL_DATA, //!< unspendable OP_RETURN script that carries data WITNESS_V0_SCRIPTHASH, WITNESS_V0_KEYHASH, + WITNESS_V1_TAPROOT, WITNESS_UNKNOWN, //!< Only for Witness versions not already defined above }; @@ -206,7 +207,8 @@ struct WitnessUnknown * * ScriptHash: TxoutType::SCRIPTHASH destination (P2SH) * * WitnessV0ScriptHash: TxoutType::WITNESS_V0_SCRIPTHASH destination (P2WSH) * * WitnessV0KeyHash: TxoutType::WITNESS_V0_KEYHASH destination (P2WPKH) - * * WitnessUnknown: TxoutType::WITNESS_UNKNOWN destination (P2W???) + * * WitnessUnknown: TxoutType::WITNESS_UNKNOWN/WITNESS_V1_TAPROOT destination (P2W???) + * (taproot outputs do not require their own type as long as no wallet support exists) * A CTxDestination is the internal data type encoded in a bitcoin address */ typedef boost::variant<CNoDestination, PKHash, ScriptHash, WitnessV0ScriptHash, WitnessV0KeyHash, WitnessUnknown> CTxDestination; diff --git a/src/test/fuzz/script_assets_test_minimizer.cpp b/src/test/fuzz/script_assets_test_minimizer.cpp new file mode 100644 index 0000000000..d20fa43d68 --- /dev/null +++ b/src/test/fuzz/script_assets_test_minimizer.cpp @@ -0,0 +1,200 @@ +// Copyright (c) 2020 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 <boost/algorithm/string.hpp> +#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 --dumptests; done +// $ ... +// +// (fuzz test build) +// $ mkdir dump-min +// $ ./src/test/fuzz/script_assets_test_minimizer -merge=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 { + VectorReader(SER_DISK, SERIALIZE_TRANSACTION_NO_WITNESS, CheckedParseHex(str), 0) >> 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 { + VectorReader(SER_DISK, 0, CheckedParseHex(univalue[i].get_str()), 0) >> 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; + boost::algorithm::split(words, str, boost::algorithm::is_any_of(",")); + + 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"].get_int64(); + 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); + 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); + 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); + } + } + } +} + +ECCVerifyHandle handle; + +} + +void test_one_input(const std::vector<uint8_t>& buffer) +{ + 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&) {} +} diff --git a/src/test/fuzz/script_sigcache.cpp b/src/test/fuzz/script_sigcache.cpp index 434a47b702..87af71897b 100644 --- a/src/test/fuzz/script_sigcache.cpp +++ b/src/test/fuzz/script_sigcache.cpp @@ -35,11 +35,19 @@ void test_one_input(const std::vector<uint8_t>& buffer) const bool store = fuzzed_data_provider.ConsumeBool(); PrecomputedTransactionData tx_data; CachingTransactionSignatureChecker caching_transaction_signature_checker{mutable_transaction ? &tx : nullptr, n_in, amount, store, tx_data}; - const std::optional<CPubKey> pub_key = ConsumeDeserializable<CPubKey>(fuzzed_data_provider); - if (pub_key) { - const std::vector<uint8_t> random_bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider); - if (!random_bytes.empty()) { - (void)caching_transaction_signature_checker.VerifySignature(random_bytes, *pub_key, ConsumeUInt256(fuzzed_data_provider)); + if (fuzzed_data_provider.ConsumeBool()) { + const auto random_bytes = fuzzed_data_provider.ConsumeBytes<unsigned char>(64); + const XOnlyPubKey pub_key(ConsumeUInt256(fuzzed_data_provider)); + if (random_bytes.size() == 64) { + (void)caching_transaction_signature_checker.VerifySchnorrSignature(random_bytes, pub_key, ConsumeUInt256(fuzzed_data_provider)); + } + } else { + const auto random_bytes = ConsumeRandomLengthByteVector(fuzzed_data_provider); + const auto pub_key = ConsumeDeserializable<CPubKey>(fuzzed_data_provider); + if (pub_key) { + if (!random_bytes.empty()) { + (void)caching_transaction_signature_checker.VerifyECDSASignature(random_bytes, *pub_key, ConsumeUInt256(fuzzed_data_provider)); + } } } } diff --git a/src/test/fuzz/signature_checker.cpp b/src/test/fuzz/signature_checker.cpp index 3aaeb66649..e121c89665 100644 --- a/src/test/fuzz/signature_checker.cpp +++ b/src/test/fuzz/signature_checker.cpp @@ -28,7 +28,12 @@ public: { } - bool CheckSig(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override + bool CheckECDSASignature(const std::vector<unsigned char>& scriptSig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override + { + return m_fuzzed_data_provider.ConsumeBool(); + } + + bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, const ScriptExecutionData& execdata, ScriptError* serror = nullptr) const override { return m_fuzzed_data_provider.ConsumeBool(); } diff --git a/src/test/key_tests.cpp b/src/test/key_tests.cpp index 4e4c44266a..3362b8d17c 100644 --- a/src/test/key_tests.cpp +++ b/src/test/key_tests.cpp @@ -264,4 +264,32 @@ BOOST_AUTO_TEST_CASE(pubkey_unserialize) } } +BOOST_AUTO_TEST_CASE(bip340_test_vectors) +{ + static const std::vector<std::pair<std::array<std::string, 3>, bool>> VECTORS = { + {{"F9308A019258C31049344F85F89D5229B531C845836F99B08601F113BCE036F9", "0000000000000000000000000000000000000000000000000000000000000000", "E907831F80848D1069A5371B402410364BDF1C5F8307B0084C55F1CE2DCA821525F66A4A85EA8B71E482A74F382D2CE5EBEEE8FDB2172F477DF4900D310536C0"}, true}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "6896BD60EEAE296DB48A229FF71DFE071BDE413E6D43F917DC8DCF8C78DE33418906D11AC976ABCCB20B091292BFF4EA897EFCB639EA871CFA95F6DE339E4B0A"}, true}, + {{"DD308AFEC5777E13121FA72B9CC1B7CC0139715309B086C960E18FD969774EB8", "7E2D58D8B3BCDF1ABADEC7829054F90DDA9805AAB56C77333024B9D0A508B75C", "5831AAEED7B44BB74E5EAB94BA9D4294C49BCF2A60728D8B4C200F50DD313C1BAB745879A5AD954A72C45A91C3A51D3C7ADEA98D82F8481E0E1E03674A6F3FB7"}, true}, + {{"25D1DFF95105F5253C4022F628A996AD3A0D95FBF21D468A1B33F8C160D8F517", "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF", "7EB0509757E246F19449885651611CB965ECC1A187DD51B64FDA1EDC9637D5EC97582B9CB13DB3933705B32BA982AF5AF25FD78881EBB32771FC5922EFC66EA3"}, true}, + {{"D69C3509BB99E412E68B0FE8544E72837DFA30746D8BE2AA65975F29D22DC7B9", "4DF3C3F68FCC83B27E9D42C90431A72499F17875C81A599B566C9889B9696703", "00000000000000000000003B78CE563F89A0ED9414F5AA28AD0D96D6795F9C6376AFB1548AF603B3EB45C9F8207DEE1060CB71C04E80F593060B07D28308D7F4"}, true}, + {{"EEFDEA4CDB677750A420FEE807EACF21EB9898AE79B9768766E4FAA04A2D4A34", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "FFF97BD5755EEEA420453A14355235D382F6472F8568A18B2F057A14602975563CC27944640AC607CD107AE10923D9EF7A73C643E166BE5EBEAFA34B1AC553E2"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "1FA62E331EDBC21C394792D2AB1100A7B432B013DF3F6FF4F99FCB33E0E1515F28890B3EDB6E7189B630448B515CE4F8622A954CFE545735AAEA5134FCCDB2BD"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769961764B3AA9B2FFCB6EF947B6887A226E8D7C93E00C5ED0C1834FF0D0C2E6DA6"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "0000000000000000000000000000000000000000000000000000000000000000123DDA8328AF9C23A94C1FEECFD123BA4FB73476F0D594DCB65C6425BD186051"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "00000000000000000000000000000000000000000000000000000000000000017615FBAF5AE28864013C099742DEADB4DBA87F11AC6754F93780D5A1837CF197"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "4A298DACAE57395A15D0795DDBFD1DCB564DA82B0F269BC70A74F8220429BA1D69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B"}, false}, + {{"DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141"}, false}, + {{"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC30", "243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89", "6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B"}, false} + }; + + for (const auto& test : VECTORS) { + auto pubkey = ParseHex(test.first[0]); + auto msg = ParseHex(test.first[1]); + auto sig = ParseHex(test.first[2]); + BOOST_CHECK_EQUAL(XOnlyPubKey(pubkey).VerifySchnorr(uint256(msg), sig), test.second); + } +} + BOOST_AUTO_TEST_SUITE_END() diff --git a/src/test/script_tests.cpp b/src/test/script_tests.cpp index 0830743d61..a2efd8ac07 100644 --- a/src/test/script_tests.cpp +++ b/src/test/script_tests.cpp @@ -5,10 +5,12 @@ #include <test/data/script_tests.json.h> #include <core_io.h> +#include <fs.h> #include <key.h> #include <rpc/util.h> #include <script/script.h> #include <script/script_error.h> +#include <script/sigcache.h> #include <script/sign.h> #include <script/signingprovider.h> #include <streams.h> @@ -1339,13 +1341,41 @@ BOOST_AUTO_TEST_CASE(script_GetScriptAsm) BOOST_CHECK_EQUAL(derSig + "83 " + pubKey, ScriptToAsmStr(CScript() << ToByteVector(ParseHex(derSig + "83")) << vchPubKey)); } -static CScript -ScriptFromHex(const char* hex) +static CScript ScriptFromHex(const std::string& str) { - std::vector<unsigned char> data = ParseHex(hex); + std::vector<unsigned char> data = ParseHex(str); return CScript(data.begin(), data.end()); } +static CMutableTransaction TxFromHex(const std::string& str) +{ + CMutableTransaction tx; + VectorReader(SER_DISK, SERIALIZE_TRANSACTION_NO_WITNESS, ParseHex(str), 0) >> tx; + return tx; +} + +static std::vector<CTxOut> TxOutsFromJSON(const UniValue& univalue) +{ + assert(univalue.isArray()); + std::vector<CTxOut> prevouts; + for (size_t i = 0; i < univalue.size(); ++i) { + CTxOut txout; + VectorReader(SER_DISK, 0, ParseHex(univalue[i].get_str()), 0) >> txout; + prevouts.push_back(std::move(txout)); + } + return prevouts; +} + +static CScriptWitness ScriptWitnessFromJSON(const UniValue& univalue) +{ + assert(univalue.isArray()); + CScriptWitness scriptwitness; + for (size_t i = 0; i < univalue.size(); ++i) { + auto bytes = ParseHex(univalue[i].get_str()); + scriptwitness.stack.push_back(std::move(bytes)); + } + return scriptwitness; +} BOOST_AUTO_TEST_CASE(script_FindAndDelete) { @@ -1610,5 +1640,107 @@ BOOST_AUTO_TEST_CASE(bitcoinconsensus_verify_script_invalid_flags) BOOST_CHECK_EQUAL(err, bitcoinconsensus_ERR_INVALID_FLAGS); } +static std::vector<unsigned int> AllConsensusFlags() +{ + 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; +} + +/** Precomputed list of all valid combinations of consensus-relevant script validation flags. */ +static const std::vector<unsigned int> ALL_CONSENSUS_FLAGS = AllConsensusFlags(); + +static void AssetTest(const UniValue& test) +{ + BOOST_CHECK(test.isObject()); + + CMutableTransaction mtx = TxFromHex(test["tx"].get_str()); + const std::vector<CTxOut> prevouts = TxOutsFromJSON(test["prevouts"]); + BOOST_CHECK(prevouts.size() == mtx.vin.size()); + size_t idx = test["index"].get_int64(); + unsigned int test_flags = ParseScriptFlags(test["flags"].get_str()); + bool fin = test.exists("final") && test["final"].get_bool(); + + if (test.exists("success")) { + mtx.vin[idx].scriptSig = ScriptFromHex(test["success"]["scriptSig"].get_str()); + mtx.vin[idx].scriptWitness = ScriptWitnessFromJSON(test["success"]["witness"]); + CTransaction tx(mtx); + PrecomputedTransactionData txdata; + txdata.Init(tx, std::vector<CTxOut>(prevouts)); + CachingTransactionSignatureChecker txcheck(&tx, idx, prevouts[idx].nValue, true, txdata); + for (const auto flags : ALL_CONSENSUS_FLAGS) { + // "final": true tests are valid for all flags. Others are only valid with flags that are + // a subset of test_flags. + if (fin || ((flags & test_flags) == flags)) { + bool ret = VerifyScript(tx.vin[idx].scriptSig, prevouts[idx].scriptPubKey, &tx.vin[idx].scriptWitness, flags, txcheck, nullptr); + BOOST_CHECK(ret); + } + } + } + + if (test.exists("failure")) { + mtx.vin[idx].scriptSig = ScriptFromHex(test["failure"]["scriptSig"].get_str()); + mtx.vin[idx].scriptWitness = ScriptWitnessFromJSON(test["failure"]["witness"]); + CTransaction tx(mtx); + PrecomputedTransactionData txdata; + txdata.Init(tx, std::vector<CTxOut>(prevouts)); + CachingTransactionSignatureChecker txcheck(&tx, idx, prevouts[idx].nValue, true, txdata); + for (const auto flags : ALL_CONSENSUS_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) { + bool ret = VerifyScript(tx.vin[idx].scriptSig, prevouts[idx].scriptPubKey, &tx.vin[idx].scriptWitness, flags, txcheck, nullptr); + BOOST_CHECK(!ret); + } + } + } +} + +BOOST_AUTO_TEST_CASE(script_assets_test) +{ + // See src/test/fuzz/script_assets_test_minimizer.cpp for information on how to generate + // the script_assets_test.json file used by this test. + + const char* dir = std::getenv("DIR_UNIT_TEST_DATA"); + BOOST_WARN_MESSAGE(dir != nullptr, "Variable DIR_UNIT_TEST_DATA unset, skipping script_assets_test"); + if (dir == nullptr) return; + auto path = fs::path(dir) / "script_assets_test.json"; + bool exists = fs::exists(path); + BOOST_WARN_MESSAGE(exists, "File $DIR_UNIT_TEST_DATA/script_assets_test.json not found, skipping script_assets_test"); + if (!exists) return; + fs::ifstream file(path); + BOOST_CHECK(file.is_open()); + file.seekg(0, std::ios::end); + size_t length = file.tellg(); + file.seekg(0, std::ios::beg); + std::string data(length, '\0'); + file.read(&data[0], data.size()); + UniValue tests = read_json(data); + BOOST_CHECK(tests.isArray()); + BOOST_CHECK(tests.size() > 0); + + for (size_t i = 0; i < tests.size(); i++) { + AssetTest(tests[i]); + } + file.close(); +} + #endif BOOST_AUTO_TEST_SUITE_END() diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp index 94b5dba913..b7ee280336 100644 --- a/src/test/transaction_tests.cpp +++ b/src/test/transaction_tests.cpp @@ -57,6 +57,7 @@ static std::map<std::string, unsigned int> mapFlagNames = { {std::string("DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM"), (unsigned int)SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM}, {std::string("WITNESS_PUBKEYTYPE"), (unsigned int)SCRIPT_VERIFY_WITNESS_PUBKEYTYPE}, {std::string("CONST_SCRIPTCODE"), (unsigned int)SCRIPT_VERIFY_CONST_SCRIPTCODE}, + {std::string("TAPROOT"), (unsigned int)SCRIPT_VERIFY_TAPROOT}, }; unsigned int ParseScriptFlags(std::string strFlags) diff --git a/src/validation.cpp b/src/validation.cpp index 06b9b36fca..423b93479a 100644 --- a/src/validation.cpp +++ b/src/validation.cpp @@ -1532,14 +1532,21 @@ bool CheckInputScripts(const CTransaction& tx, TxValidationState &state, const C return true; } - if (!txdata.m_ready) { - txdata.Init(tx); + 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++) { - const COutPoint &prevout = tx.vin[i].prevout; - const Coin& coin = inputs.AccessCoin(prevout); - assert(!coin.IsSpent()); // We very carefully only pass in things to CScriptCheck which // are clearly committed to by tx' witness hash. This provides @@ -1548,7 +1555,7 @@ bool CheckInputScripts(const CTransaction& tx, TxValidationState &state, const C // spent being checked as a part of CScriptCheck. // Verify signature - CScriptCheck check(coin.out, tx, i, flags, cacheSigStore, &txdata); + CScriptCheck check(txdata.m_spent_outputs[i], tx, i, flags, cacheSigStore, &txdata); if (pvChecks) { pvChecks->push_back(CScriptCheck()); check.swap(pvChecks->back()); @@ -1562,7 +1569,7 @@ bool CheckInputScripts(const CTransaction& tx, TxValidationState &state, const C // splitting the network between upgraded and // non-upgraded nodes by banning CONSENSUS-failing // data providers. - CScriptCheck check2(coin.out, tx, i, + 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()))); @@ -1907,6 +1914,11 @@ static unsigned int GetBlockScriptFlags(const CBlockIndex* pindex, const Consens flags |= SCRIPT_VERIFY_CHECKSEQUENCEVERIFY; } + // Start enforcing Taproot using versionbits logic. + if (VersionBitsState(pindex->pprev, consensusparams, Consensus::DEPLOYMENT_TAPROOT, versionbitscache) == ThresholdState::ACTIVE) { + flags |= SCRIPT_VERIFY_TAPROOT; + } + // Start enforcing BIP147 NULLDUMMY (activated simultaneously with segwit) if (IsWitnessEnabled(pindex->pprev, consensusparams)) { flags |= SCRIPT_VERIFY_NULLDUMMY; diff --git a/src/versionbitsinfo.cpp b/src/versionbitsinfo.cpp index 20297b9f9d..20dfc044ca 100644 --- a/src/versionbitsinfo.cpp +++ b/src/versionbitsinfo.cpp @@ -11,4 +11,8 @@ const struct VBDeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_B /*.name =*/ "testdummy", /*.gbt_force =*/ true, }, + { + /*.name =*/ "taproot", + /*.gbt_force =*/ true, + }, }; diff --git a/src/wallet/rpcdump.cpp b/src/wallet/rpcdump.cpp index 9e36a09780..7dcab46ad3 100644 --- a/src/wallet/rpcdump.cpp +++ b/src/wallet/rpcdump.cpp @@ -932,6 +932,7 @@ static std::string RecurseImportData(const CScript& script, ImportData& import_d return "unspendable script"; case TxoutType::NONSTANDARD: case TxoutType::WITNESS_UNKNOWN: + case TxoutType::WITNESS_V1_TAPROOT: default: return "unrecognized script"; } diff --git a/src/wallet/scriptpubkeyman.cpp b/src/wallet/scriptpubkeyman.cpp index 435716e56a..b7c70dac3a 100644 --- a/src/wallet/scriptpubkeyman.cpp +++ b/src/wallet/scriptpubkeyman.cpp @@ -96,6 +96,7 @@ IsMineResult IsMineInner(const LegacyScriptPubKeyMan& keystore, const CScript& s case TxoutType::NONSTANDARD: case TxoutType::NULL_DATA: case TxoutType::WITNESS_UNKNOWN: + case TxoutType::WITNESS_V1_TAPROOT: break; case TxoutType::PUBKEY: keyID = CPubKey(vSolutions[0]).GetID(); |