diff options
| author | Johnson Lau <jl2012@xbt.hk> | 2018-04-27 03:56:29 +0800 |
|---|---|---|
| committer | Johnson Lau <jl2012@xbt.hk> | 2018-05-05 04:26:12 +0800 |
| commit | 9dabfe49c066301ef75bcfcb089fd308366127c4 (patch) | |
| tree | 9640b1303dc21c3dc68463833d9f34145a118b2e /src/script/interpreter.cpp | |
| parent | 627c3762ce5d8ce097f70c7fb52a3640246fae9b (diff) | |
Add constant scriptCode policy in non-segwit scripts
This disables OP_CODESEPARATOR in non-segwit scripts (even in an unexecuted branch), and makes a positive FindAndDelete result invalid. This ensures that the scriptCode serialized in SignatureHash() is always the same as the script passing to the EvalScript.
Diffstat (limited to 'src/script/interpreter.cpp')
| -rw-r--r-- | src/script/interpreter.cpp | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index e0d193fa38..13f41a7cbf 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -336,6 +336,10 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& opcode == OP_RSHIFT) return set_error(serror, SCRIPT_ERR_DISABLED_OPCODE); // Disabled opcodes. + // With SCRIPT_VERIFY_CONST_SCRIPTCODE, OP_CODESEPARATOR in non-segwit script is rejected even in an unexecuted branch + if (opcode == OP_CODESEPARATOR && sigversion == SigVersion::BASE && (flags & SCRIPT_VERIFY_CONST_SCRIPTCODE)) + return set_error(serror, SCRIPT_ERR_OP_CODESEPARATOR); + if (fExec && 0 <= opcode && opcode <= OP_PUSHDATA4) { if (fRequireMinimal && !CheckMinimalPush(vchPushValue, opcode)) { return set_error(serror, SCRIPT_ERR_MINIMALDATA); @@ -899,6 +903,9 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& case OP_CODESEPARATOR: { + // If SCRIPT_VERIFY_CONST_SCRIPTCODE flag is set, use of OP_CODESEPARATOR is rejected in pre-segwit + // script, even in an unexecuted branch (this is checked above the opcode case statement). + // Hash starts after the code separator pbegincodehash = pc; } @@ -919,7 +926,9 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& // Drop the signature in pre-segwit scripts but not segwit scripts if (sigversion == SigVersion::BASE) { - FindAndDelete(scriptCode, CScript(vchSig)); + int found = FindAndDelete(scriptCode, CScript(vchSig)); + if (found > 0 && (flags & SCRIPT_VERIFY_CONST_SCRIPTCODE)) + return set_error(serror, SCRIPT_ERR_SIG_FINDANDDELETE); } if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, sigversion, serror)) { @@ -983,7 +992,9 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& { valtype& vchSig = stacktop(-isig-k); if (sigversion == SigVersion::BASE) { - FindAndDelete(scriptCode, CScript(vchSig)); + int found = FindAndDelete(scriptCode, CScript(vchSig)); + if (found > 0 && (flags & SCRIPT_VERIFY_CONST_SCRIPTCODE)) + return set_error(serror, SCRIPT_ERR_SIG_FINDANDDELETE); } } |