diff options
Diffstat (limited to 'src/script')
| -rw-r--r-- | src/script/interpreter.cpp | 20 | ||||
| -rw-r--r-- | src/script/interpreter.h | 8 | ||||
| -rw-r--r-- | src/script/script_error.cpp | 4 | ||||
| -rw-r--r-- | src/script/script_error.h | 4 |
4 files changed, 34 insertions, 2 deletions
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index 47ea261e31..41756ea711 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -428,6 +428,12 @@ 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; @@ -879,6 +885,9 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un } 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 +917,9 @@ 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); @@ -964,8 +976,14 @@ 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. diff --git a/src/script/interpreter.h b/src/script/interpreter.h index e5d7865cd3..0adc9482ff 100644 --- a/src/script/interpreter.h +++ b/src/script/interpreter.h @@ -94,6 +94,14 @@ enum // Making v1-v16 witness program non-standard // SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM = (1U << 12), + + // Segwit script only: Require the argument of OP_IF/NOTIF to be exactly 0x01 or empty vector + // + SCRIPT_VERIFY_MINIMALIF = (1U << 13), + + // Signature(s) must be empty vector if an CHECK(MULTI)SIG operation failed + // + SCRIPT_VERIFY_NULLFAIL = (1U << 14), }; bool CheckSignatureEncoding(const std::vector<unsigned char> &vchSig, unsigned int flags, ScriptError* serror); diff --git a/src/script/script_error.cpp b/src/script/script_error.cpp index cef807edcf..e27b715c2c 100644 --- a/src/script/script_error.cpp +++ b/src/script/script_error.cpp @@ -63,6 +63,10 @@ const char* ScriptErrorString(const ScriptError serror) return "Non-canonical signature: S value is unnecessarily high"; case SCRIPT_ERR_SIG_NULLDUMMY: return "Dummy CHECKMULTISIG argument must be zero"; + case SCRIPT_ERR_MINIMALIF: + return "OP_IF/NOTIF argument must be minimal"; + case SCRIPT_ERR_SIG_NULLFAIL: + return "Signature must be zero for failed CHECK(MULTI)SIG operation"; case SCRIPT_ERR_DISCOURAGE_UPGRADABLE_NOPS: return "NOPx reserved for soft-fork upgrades"; case SCRIPT_ERR_DISCOURAGE_UPGRADABLE_WITNESS_PROGRAM: diff --git a/src/script/script_error.h b/src/script/script_error.h index 09dc6945ad..bccfdb99e2 100644 --- a/src/script/script_error.h +++ b/src/script/script_error.h @@ -39,7 +39,7 @@ typedef enum ScriptError_t SCRIPT_ERR_NEGATIVE_LOCKTIME, SCRIPT_ERR_UNSATISFIED_LOCKTIME, - /* BIP62 */ + /* Malleability */ SCRIPT_ERR_SIG_HASHTYPE, SCRIPT_ERR_SIG_DER, SCRIPT_ERR_MINIMALDATA, @@ -48,6 +48,8 @@ typedef enum ScriptError_t SCRIPT_ERR_SIG_NULLDUMMY, SCRIPT_ERR_PUBKEYTYPE, SCRIPT_ERR_CLEANSTACK, + SCRIPT_ERR_MINIMALIF, + SCRIPT_ERR_SIG_NULLFAIL, /* softfork safeness */ SCRIPT_ERR_DISCOURAGE_UPGRADABLE_NOPS, |