X-Git-Url: https://git.novaco.in/?p=novacoin.git;a=blobdiff_plain;f=src%2Fscript.cpp;h=ea44c63edb933c6737a7556ff582ad7d0825efb4;hp=64208c5d63b014b2c429efbc3a59c1672a313410;hb=1c4fc9052a444c114d9c1501d2c6d1305de650d0;hpb=a3b8fbc4443829bfc133ed407c5e3865b4b9d400 diff --git a/src/script.cpp b/src/script.cpp index 64208c5..ea44c63 100644 --- a/src/script.cpp +++ b/src/script.cpp @@ -16,7 +16,7 @@ using namespace boost; #include "sync.h" #include "util.h" -bool CheckSig(vector vchSig, vector vchPubKey, CScript scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType); +bool CheckSig(vector vchSig, const vector &vchPubKey, const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType, int flags); static const valtype vchFalse(0); static const valtype vchZero(0); @@ -252,7 +252,80 @@ const char* GetOpName(opcodetype opcode) } } -bool EvalScript(vector >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, int nHashType) +bool IsCanonicalPubKey(const valtype &vchPubKey, unsigned int flags) { + if (!(flags & SCRIPT_VERIFY_STRICTENC)) + return true; + + if (vchPubKey.size() < 33) + return error("Non-canonical public key: too short"); + if (vchPubKey[0] == 0x04) { + if (vchPubKey.size() != 65) + return error("Non-canonical public key: invalid length for uncompressed key"); + } else if (vchPubKey[0] == 0x02 || vchPubKey[0] == 0x03) { + if (vchPubKey.size() != 33) + return error("Non-canonical public key: invalid length for compressed key"); + } else { + return error("Non-canonical public key: compressed nor uncompressed"); + } + return true; +} + +bool IsCanonicalSignature(const valtype &vchSig, unsigned int flags) { + if (!(flags & SCRIPT_VERIFY_STRICTENC)) + return true; + + // See https://bitcointalk.org/index.php?topic=8392.msg127623#msg127623 + // A canonical signature exists of: <30> <02> <02> + // Where R and S are not negative (their first byte has its highest bit not set), and not + // excessively padded (do not start with a 0 byte, unless an otherwise negative number follows, + // in which case a single 0 byte is necessary and even required). + if (vchSig.size() < 9) + return error("Non-canonical signature: too short"); + if (vchSig.size() > 73) + return error("Non-canonical signature: too long"); + unsigned char nHashType = vchSig[vchSig.size() - 1] & (~(SIGHASH_ANYONECANPAY)); + if (nHashType < SIGHASH_ALL || nHashType > SIGHASH_SINGLE) + return error("Non-canonical signature: unknown hashtype byte"); + if (vchSig[0] != 0x30) + return error("Non-canonical signature: wrong type"); + if (vchSig[1] != vchSig.size()-3) + return error("Non-canonical signature: wrong length marker"); + unsigned int nLenR = vchSig[3]; + if (5 + nLenR >= vchSig.size()) + return error("Non-canonical signature: S length misplaced"); + unsigned int nLenS = vchSig[5+nLenR]; + if ((unsigned long)(nLenR+nLenS+7) != vchSig.size()) + return error("Non-canonical signature: R+S length mismatch"); + + const unsigned char *R = &vchSig[4]; + if (R[-2] != 0x02) + return error("Non-canonical signature: R value type mismatch"); + if (nLenR == 0) + return error("Non-canonical signature: R length is zero"); + if (R[0] & 0x80) + return error("Non-canonical signature: R value negative"); + if (nLenR > 1 && (R[0] == 0x00) && !(R[1] & 0x80)) + return error("Non-canonical signature: R value excessively padded"); + + const unsigned char *S = &vchSig[6+nLenR]; + if (S[-2] != 0x02) + return error("Non-canonical signature: S value type mismatch"); + if (nLenS == 0) + return error("Non-canonical signature: S length is zero"); + if (S[0] & 0x80) + return error("Non-canonical signature: S value negative"); + if (nLenS > 1 && (S[0] == 0x00) && !(S[1] & 0x80)) + return error("Non-canonical signature: S value excessively padded"); + + if (flags & SCRIPT_VERIFY_LOW_S) { + if (!CKey::CheckSignatureElement(S, nLenS, true)) + return error("Non-canonical signature: S value is unnecessarily high"); + } + + return true; +} + +bool EvalScript(vector >& stack, const CScript& script, const CTransaction& txTo, unsigned int nIn, unsigned int flags, int nHashType) { CAutoBN_CTX pctx; CScript::const_iterator pc = script.begin(); @@ -266,7 +339,6 @@ bool EvalScript(vector >& stack, const CScript& script, co return false; int nOpCount = 0; - try { while (pc < pend) @@ -278,7 +350,7 @@ bool EvalScript(vector >& stack, const CScript& script, co // if (!script.GetOp(pc, opcode, vchPushValue)) return false; - if (vchPushValue.size() > 520) + if (vchPushValue.size() > MAX_SCRIPT_ELEMENT_SIZE) return false; if (opcode > OP_16 && ++nOpCount > 201) return false; @@ -298,7 +370,7 @@ bool EvalScript(vector >& stack, const CScript& script, co opcode == OP_MOD || opcode == OP_LSHIFT || opcode == OP_RSHIFT) - return false; + return false; // Disabled opcodes. if (fExec && 0 <= opcode && opcode <= OP_PUSHDATA4) stack.push_back(vchPushValue); @@ -596,64 +668,6 @@ bool EvalScript(vector >& stack, const CScript& script, co break; - // - // Splice ops - // - case OP_CAT: - { - // (x1 x2 -- out) - if (stack.size() < 2) - return false; - valtype& vch1 = stacktop(-2); - valtype& vch2 = stacktop(-1); - vch1.insert(vch1.end(), vch2.begin(), vch2.end()); - popstack(stack); - if (stacktop(-1).size() > 520) - return false; - } - break; - - case OP_SUBSTR: - { - // (in begin size -- out) - if (stack.size() < 3) - return false; - valtype& vch = stacktop(-3); - int nBegin = CastToBigNum(stacktop(-2)).getint(); - int nEnd = nBegin + CastToBigNum(stacktop(-1)).getint(); - if (nBegin < 0 || nEnd < nBegin) - return false; - if (nBegin > (int)vch.size()) - nBegin = vch.size(); - if (nEnd > (int)vch.size()) - nEnd = vch.size(); - vch.erase(vch.begin() + nEnd, vch.end()); - vch.erase(vch.begin(), vch.begin() + nBegin); - popstack(stack); - popstack(stack); - } - break; - - case OP_LEFT: - case OP_RIGHT: - { - // (in size -- out) - if (stack.size() < 2) - return false; - valtype& vch = stacktop(-2); - int nSize = CastToBigNum(stacktop(-1)).getint(); - if (nSize < 0) - return false; - if (nSize > (int)vch.size()) - nSize = vch.size(); - if (opcode == OP_LEFT) - vch.erase(vch.begin() + nSize, vch.end()); - else - vch.erase(vch.begin(), vch.end() - nSize); - popstack(stack); - } - break; - case OP_SIZE: { // (in -- in size) @@ -668,51 +682,6 @@ bool EvalScript(vector >& stack, const CScript& script, co // // Bitwise logic // - case OP_INVERT: - { - // (in - out) - if (stack.size() < 1) - return false; - valtype& vch = stacktop(-1); - for (unsigned int i = 0; i < vch.size(); i++) - vch[i] = ~vch[i]; - } - break; - - // - // WARNING: These disabled opcodes exhibit unexpected behavior - // when used on signed integers due to a bug in MakeSameSize() - // [see definition of MakeSameSize() above]. - // - case OP_AND: - case OP_OR: - case OP_XOR: - { - // (x1 x2 - out) - if (stack.size() < 2) - return false; - valtype& vch1 = stacktop(-2); - valtype& vch2 = stacktop(-1); - MakeSameSize(vch1, vch2); // <-- NOT SAFE FOR SIGNED VALUES - if (opcode == OP_AND) - { - for (unsigned int i = 0; i < vch1.size(); i++) - vch1[i] &= vch2[i]; - } - else if (opcode == OP_OR) - { - for (unsigned int i = 0; i < vch1.size(); i++) - vch1[i] |= vch2[i]; - } - else if (opcode == OP_XOR) - { - for (unsigned int i = 0; i < vch1.size(); i++) - vch1[i] ^= vch2[i]; - } - popstack(stack); - } - break; - case OP_EQUAL: case OP_EQUALVERIFY: //case OP_NOTEQUAL: // use OP_NUMNOTEQUAL @@ -747,8 +716,6 @@ bool EvalScript(vector >& stack, const CScript& script, co // case OP_1ADD: case OP_1SUB: - case OP_2MUL: - case OP_2DIV: case OP_NEGATE: case OP_ABS: case OP_NOT: @@ -762,8 +729,6 @@ bool EvalScript(vector >& stack, const CScript& script, co { case OP_1ADD: bn += bnOne; break; case OP_1SUB: bn -= bnOne; break; - case OP_2MUL: bn <<= 1; break; - case OP_2DIV: bn >>= 1; break; case OP_NEGATE: bn = -bn; break; case OP_ABS: if (bn < bnZero) bn = -bn; break; case OP_NOT: bn = (bn == bnZero); break; @@ -777,11 +742,6 @@ bool EvalScript(vector >& stack, const CScript& script, co case OP_ADD: case OP_SUB: - case OP_MUL: - case OP_DIV: - case OP_MOD: - case OP_LSHIFT: - case OP_RSHIFT: case OP_BOOLAND: case OP_BOOLOR: case OP_NUMEQUAL: @@ -810,33 +770,6 @@ bool EvalScript(vector >& stack, const CScript& script, co bn = bn1 - bn2; break; - case OP_MUL: - if (!BN_mul(&bn, &bn1, &bn2, pctx)) - return false; - break; - - case OP_DIV: - if (!BN_div(&bn, NULL, &bn1, &bn2, pctx)) - return false; - break; - - case OP_MOD: - if (!BN_mod(&bn, &bn1, &bn2, pctx)) - return false; - break; - - case OP_LSHIFT: - if (bn2 < bnZero || bn2 > CBigNum(2048)) - return false; - bn = bn1 << bn2.getulong(); - break; - - case OP_RSHIFT: - if (bn2 < bnZero || bn2 > CBigNum(2048)) - return false; - bn = bn1 >> bn2.getulong(); - break; - case OP_BOOLAND: bn = (bn1 != bnZero && bn2 != bnZero); break; case OP_BOOLOR: bn = (bn1 != bnZero || bn2 != bnZero); break; case OP_NUMEQUAL: bn = (bn1 == bn2); break; @@ -943,7 +876,8 @@ bool EvalScript(vector >& stack, const CScript& script, co // Drop the signature, since there's no way for a signature to sign itself scriptCode.FindAndDelete(CScript(vchSig)); - bool fSuccess = CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType); + bool fSuccess = IsCanonicalSignature(vchSig, flags) && IsCanonicalPubKey(vchPubKey, flags) && + CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags); popstack(stack); popstack(stack); @@ -1003,8 +937,10 @@ bool EvalScript(vector >& stack, const CScript& script, co valtype& vchPubKey = stacktop(-ikey); // Check signature - if (CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType)) - { + bool fOk = IsCanonicalSignature(vchSig, flags) && IsCanonicalPubKey(vchPubKey, flags) && + CheckSig(vchSig, vchPubKey, scriptCode, txTo, nIn, nHashType, flags); + + if (fOk) { isig++; nSigsCount--; } @@ -1017,8 +953,21 @@ bool EvalScript(vector >& stack, const CScript& script, co fSuccess = false; } - while (i-- > 0) + while (i-- > 1) popstack(stack); + + // A bug causes CHECKMULTISIG to consume one extra argument + // whose contents were not checked in any way. + // + // Unfortunately this is a potential source of mutability, + // so optionally verify it is exactly equal to zero prior + // to removing it from the stack. + if (stack.size() < 1) + return false; + if ((flags & SCRIPT_VERIFY_NULLDUMMY) && stacktop(-1).size()) + return error("CHECKMULTISIG dummy argument not null"); + popstack(stack); + stack.push_back(fSuccess ? vchTrue : vchFalse); if (opcode == OP_CHECKMULTISIGVERIFY) @@ -1131,15 +1080,15 @@ class CSignatureCache { private: // sigdata_type is (signature hash, signature, public key): - typedef boost::tuple, std::vector > sigdata_type; + typedef boost::tuple, CPubKey > sigdata_type; std::set< sigdata_type> setValid; - CCriticalSection cs_sigcache; + boost::shared_mutex cs_sigcache; public: bool - Get(uint256 hash, const std::vector& vchSig, const std::vector& pubKey) + Get(const uint256 &hash, const std::vector& vchSig, const CPubKey& pubKey) { - LOCK(cs_sigcache); + boost::shared_lock lock(cs_sigcache); sigdata_type k(hash, vchSig, pubKey); std::set::iterator mi = setValid.find(k); @@ -1148,7 +1097,7 @@ public: return false; } - void Set(uint256 hash, const std::vector& vchSig, const std::vector& pubKey) + void Set(const uint256 &hash, const std::vector& vchSig, const CPubKey& pubKey) { // DoS prevention: limit cache size to less than 10MB // (~200 bytes per cache entry times 50,000 entries) @@ -1157,7 +1106,7 @@ public: int64 nMaxCacheSize = GetArg("-maxsigcachesize", 50000); if (nMaxCacheSize <= 0) return; - LOCK(cs_sigcache); + boost::shared_lock lock(cs_sigcache); while (static_cast(setValid.size()) > nMaxCacheSize) { @@ -1179,11 +1128,18 @@ public: } }; -bool CheckSig(vector vchSig, vector vchPubKey, CScript scriptCode, - const CTransaction& txTo, unsigned int nIn, int nHashType) +bool CheckSig(vector vchSig, const vector &vchPubKey, const CScript &scriptCode, + const CTransaction& txTo, unsigned int nIn, int nHashType, int flags) { static CSignatureCache signatureCache; + CKey key; + if (!key.SetPubKey(vchPubKey)) + return false; + CPubKey pubkey = key.GetPubKey(); + if (!pubkey.IsValid()) + return false; + // Hash type is one byte tacked on to the end of the signature if (vchSig.empty()) return false; @@ -1195,17 +1151,15 @@ bool CheckSig(vector vchSig, vector vchPubKey, CSc uint256 sighash = SignatureHash(scriptCode, txTo, nIn, nHashType); - if (signatureCache.Get(sighash, vchSig, vchPubKey)) + if (signatureCache.Get(sighash, vchSig, pubkey)) return true; - CKey key; - if (!key.SetPubKey(vchPubKey)) - return false; - if (!key.Verify(sighash, vchSig)) return false; - signatureCache.Set(sighash, vchSig, vchPubKey); + if (!(flags & SCRIPT_VERIFY_NOCACHE)) + signatureCache.Set(sighash, vchSig, pubkey); + return true; } @@ -1216,7 +1170,6 @@ bool CheckSig(vector vchSig, vector vchPubKey, CSc - // // Return public keys or hashes from scriptPubKey, for 'standard' transaction types. // @@ -1482,36 +1435,49 @@ public: bool operator()(const CScriptID &scriptID) const { return keystore->HaveCScript(scriptID); } }; -bool IsMine(const CKeyStore &keystore, const CTxDestination &dest) +isminetype IsMine(const CKeyStore &keystore, const CTxDestination& dest) { - return boost::apply_visitor(CKeyStoreIsMineVisitor(&keystore), dest); + CScript script; + script.SetDestination(dest); + return IsMine(keystore, script); } -bool IsMine(const CKeyStore &keystore, const CScript& scriptPubKey) +isminetype IsMine(const CKeyStore &keystore, const CScript& scriptPubKey) { vector vSolutions; txnouttype whichType; - if (!Solver(scriptPubKey, whichType, vSolutions)) - return false; + if (!Solver(scriptPubKey, whichType, vSolutions)) { + if (keystore.HaveWatchOnly(scriptPubKey)) + return MINE_WATCH_ONLY; + return MINE_NO; + } CKeyID keyID; switch (whichType) { case TX_NONSTANDARD: case TX_NULL_DATA: - return false; + break; case TX_PUBKEY: keyID = CPubKey(vSolutions[0]).GetID(); - return keystore.HaveKey(keyID); + if (keystore.HaveKey(keyID)) + return MINE_SPENDABLE; + break; case TX_PUBKEYHASH: keyID = CKeyID(uint160(vSolutions[0])); - return keystore.HaveKey(keyID); + if (keystore.HaveKey(keyID)) + return MINE_SPENDABLE; + break; case TX_SCRIPTHASH: { + CScriptID scriptID = CScriptID(uint160(vSolutions[0])); CScript subscript; - if (!keystore.GetCScript(CScriptID(uint160(vSolutions[0])), subscript)) - return false; - return IsMine(keystore, subscript); + if (keystore.GetCScript(scriptID, subscript)) { + isminetype ret = IsMine(keystore, subscript); + if (ret == MINE_SPENDABLE) + return ret; + } + break; } case TX_MULTISIG: { @@ -1521,10 +1487,15 @@ bool IsMine(const CKeyStore &keystore, const CScript& scriptPubKey) // them) enable spend-out-from-under-you attacks, especially // in shared-wallet situations. vector keys(vSolutions.begin()+1, vSolutions.begin()+vSolutions.size()-1); - return HaveKeys(keys, keystore) == keys.size(); + if (HaveKeys(keys, keystore) == keys.size()) + return MINE_SPENDABLE; + break; } } - return false; + + if (keystore.HaveWatchOnly(scriptPubKey)) + return MINE_WATCH_ONLY; + return MINE_NO; } bool ExtractDestination(const CScript& scriptPubKey, CTxDestination& addressRet) @@ -1622,14 +1593,14 @@ bool ExtractDestinations(const CScript& scriptPubKey, txnouttype& typeRet, vecto } bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, - bool fValidatePayToScriptHash, int nHashType) + unsigned int flags, int nHashType) { vector > stack, stackCopy; - if (!EvalScript(stack, scriptSig, txTo, nIn, nHashType)) + if (!EvalScript(stack, scriptSig, txTo, nIn, flags, nHashType)) return false; - if (fValidatePayToScriptHash) + if (flags & SCRIPT_VERIFY_P2SH) stackCopy = stack; - if (!EvalScript(stack, scriptPubKey, txTo, nIn, nHashType)) + if (!EvalScript(stack, scriptPubKey, txTo, nIn, flags, nHashType)) return false; if (stack.empty()) return false; @@ -1638,16 +1609,21 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C return false; // Additional validation for spend-to-script-hash transactions: - if (fValidatePayToScriptHash && scriptPubKey.IsPayToScriptHash()) + if ((flags & SCRIPT_VERIFY_P2SH) && scriptPubKey.IsPayToScriptHash()) { if (!scriptSig.IsPushOnly()) // scriptSig must be literals-only return false; // or validation fails + // stackCopy cannot be empty here, because if it was the + // P2SH HASH <> EQUAL scriptPubKey would be evaluated with + // an empty stack and the EvalScript above would return false. + assert(!stackCopy.empty()); + const valtype& pubKeySerialized = stackCopy.back(); CScript pubKey2(pubKeySerialized.begin(), pubKeySerialized.end()); popstack(stackCopy); - if (!EvalScript(stackCopy, pubKey2, txTo, nIn, nHashType)) + if (!EvalScript(stackCopy, pubKey2, txTo, nIn, flags, nHashType)) return false; if (stackCopy.empty()) return false; @@ -1657,7 +1633,6 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C return true; } - bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CTransaction& txTo, unsigned int nIn, int nHashType) { assert(nIn < txTo.vin.size()); @@ -1690,7 +1665,7 @@ bool SignSignature(const CKeyStore &keystore, const CScript& fromPubKey, CTransa } // Test solution - return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, true, 0); + return VerifyScript(txin.scriptSig, fromPubKey, txTo, nIn, STRICT_FLAGS, 0); } bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTransaction& txTo, unsigned int nIn, int nHashType) @@ -1704,20 +1679,6 @@ bool SignSignature(const CKeyStore &keystore, const CTransaction& txFrom, CTrans return SignSignature(keystore, txout.scriptPubKey, txTo, nIn, nHashType); } -bool VerifySignature(const CTransaction& txFrom, const CTransaction& txTo, unsigned int nIn, bool fValidatePayToScriptHash, int nHashType) -{ - assert(nIn < txTo.vin.size()); - const CTxIn& txin = txTo.vin[nIn]; - if (txin.prevout.n >= txFrom.vout.size()) - return false; - const CTxOut& txout = txFrom.vout[txin.prevout.n]; - - if (txin.prevout.hash != txFrom.GetHash()) - return false; - - return VerifyScript(txin.scriptSig, txout.scriptPubKey, txTo, nIn, fValidatePayToScriptHash, nHashType); -} - static CScript PushAll(const vector& values) { CScript result; @@ -1756,7 +1717,7 @@ static CScript CombineMultisig(CScript scriptPubKey, const CTransaction& txTo, u if (sigs.count(pubkey)) continue; // Already got a sig for this pubkey - if (CheckSig(sig, pubkey, scriptPubKey, txTo, nIn, 0)) + if (CheckSig(sig, pubkey, scriptPubKey, txTo, nIn, 0, 0)) { sigs[pubkey] = sig; break; @@ -1834,9 +1795,9 @@ CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsign Solver(scriptPubKey, txType, vSolutions); vector stack1; - EvalScript(stack1, scriptSig1, CTransaction(), 0, 0); + EvalScript(stack1, scriptSig1, CTransaction(), 0, SCRIPT_VERIFY_STRICTENC, 0); vector stack2; - EvalScript(stack2, scriptSig2, CTransaction(), 0, 0); + EvalScript(stack2, scriptSig2, CTransaction(), 0, SCRIPT_VERIFY_STRICTENC, 0); return CombineSignatures(scriptPubKey, txTo, nIn, txType, vSolutions, stack1, stack2); }