diff options
Diffstat (limited to 'src/script/interpreter.cpp')
| -rw-r--r-- | src/script/interpreter.cpp | 52 |
1 files changed, 43 insertions, 9 deletions
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index 47ea261e3..0e17ddc13 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -79,8 +79,20 @@ bool static IsCompressedOrUncompressedPubKey(const valtype &vchPubKey) { return false; } } else { - // Non-canonical public key: neither compressed nor uncompressed - return false; + // Non-canonical public key: neither compressed nor uncompressed + return false; + } + return true; +} + +bool static IsCompressedPubKey(const valtype &vchPubKey) { + if (vchPubKey.size() != 33) { + // Non-canonical public key: invalid length for compressed key + return false; + } + if (vchPubKey[0] != 0x02 && vchPubKey[0] != 0x03) { + // Non-canonical public key: invalid prefix for compressed key + return false; } return true; } @@ -199,10 +211,14 @@ bool CheckSignatureEncoding(const vector<unsigned char> &vchSig, unsigned int fl return true; } -bool static CheckPubKeyEncoding(const valtype &vchSig, unsigned int flags, ScriptError* serror) { - if ((flags & SCRIPT_VERIFY_STRICTENC) != 0 && !IsCompressedOrUncompressedPubKey(vchSig)) { +bool static CheckPubKeyEncoding(const valtype &vchPubKey, unsigned int flags, const SigVersion &sigversion, ScriptError* serror) { + if ((flags & SCRIPT_VERIFY_STRICTENC) != 0 && !IsCompressedOrUncompressedPubKey(vchPubKey)) { return set_error(serror, SCRIPT_ERR_PUBKEYTYPE); } + // Only compressed keys are accepted in segwit + if ((flags & SCRIPT_VERIFY_WITNESS_PUBKEYTYPE) != 0 && sigversion == SIGVERSION_WITNESS_V0 && !IsCompressedPubKey(vchPubKey)) { + return set_error(serror, SCRIPT_ERR_WITNESS_PUBKEYTYPE); + } return true; } @@ -428,6 +444,12 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un if (stack.size() < 1) return set_error(serror, SCRIPT_ERR_UNBALANCED_CONDITIONAL); valtype& vch = stacktop(-1); + if (sigversion == SIGVERSION_WITNESS_V0 && (flags & SCRIPT_VERIFY_MINIMALIF)) { + if (vch.size() > 1) + return set_error(serror, SCRIPT_ERR_MINIMALIF); + if (vch.size() == 1 && vch[0] != 1) + return set_error(serror, SCRIPT_ERR_MINIMALIF); + } fValue = CastToBool(vch); if (opcode == OP_NOTIF) fValue = !fValue; @@ -868,17 +890,20 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un // Subset of script starting at the most recent codeseparator CScript scriptCode(pbegincodehash, pend); - // Drop the signature, since there's no way for a signature to sign itself + // Drop the signature in pre-segwit scripts but not segwit scripts if (sigversion == SIGVERSION_BASE) { scriptCode.FindAndDelete(CScript(vchSig)); } - if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, serror)) { + if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, sigversion, serror)) { //serror is set return false; } bool fSuccess = checker.CheckSig(vchSig, vchPubKey, scriptCode, sigversion); + if (!fSuccess && (flags & SCRIPT_VERIFY_NULLFAIL) && vchSig.size()) + return set_error(serror, SCRIPT_ERR_SIG_NULLFAIL); + popstack(stack); popstack(stack); stack.push_back(fSuccess ? vchTrue : vchFalse); @@ -908,6 +933,9 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un if (nOpCount > MAX_OPS_PER_SCRIPT) return set_error(serror, SCRIPT_ERR_OP_COUNT); int ikey = ++i; + // ikey2 is the position of last non-signature item in the stack. Top stack item = 1. + // With SCRIPT_VERIFY_NULLFAIL, this is used for cleanup if operation fails. + int ikey2 = nKeysCount + 2; i += nKeysCount; if ((int)stack.size() < i) return set_error(serror, SCRIPT_ERR_INVALID_STACK_OPERATION); @@ -923,7 +951,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un // Subset of script starting at the most recent codeseparator CScript scriptCode(pbegincodehash, pend); - // Drop the signatures, since there's no way for a signature to sign itself + // Drop the signature in pre-segwit scripts but not segwit scripts for (int k = 0; k < nSigsCount; k++) { valtype& vchSig = stacktop(-isig-k); @@ -941,7 +969,7 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un // Note how this makes the exact order of pubkey/signature evaluation // distinguishable by CHECKMULTISIG NOT if the STRICTENC flag is set. // See the script_(in)valid tests for details. - if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, serror)) { + if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, sigversion, serror)) { // serror is set return false; } @@ -964,8 +992,14 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un } // Clean up stack of actual arguments - while (i-- > 1) + while (i-- > 1) { + // If the operation failed, we require that all signatures must be empty vector + if (!fSuccess && (flags & SCRIPT_VERIFY_NULLFAIL) && !ikey2 && stacktop(-1).size()) + return set_error(serror, SCRIPT_ERR_SIG_NULLFAIL); + if (ikey2 > 0) + ikey2--; popstack(stack); + } // A bug causes CHECKMULTISIG to consume one extra argument // whose contents were not checked in any way. |