diff --git a/src/consensus/consensus.h b/src/consensus/consensus.h index 9c5b7d4ffb..f937844e9f 100644 --- a/src/consensus/consensus.h +++ b/src/consensus/consensus.h @@ -12,7 +12,5 @@ static const unsigned int MAX_BLOCK_SIZE = 1000000; static const unsigned int MAX_BLOCK_SIGOPS = MAX_BLOCK_SIZE/50; /** Coinbase transaction outputs can only be spent after this number of new blocks (network rule) */ static const int COINBASE_MATURITY = 100; -/** Threshold for nLockTime: below this value it is interpreted as block number, otherwise as UNIX timestamp. */ -static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov 5 00:53:20 1985 UTC #endif // BITCOIN_CONSENSUS_CONSENSUS_H diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp index 84a7432fdb..0b78fdf5a8 100644 --- a/src/script/interpreter.cpp +++ b/src/script/interpreter.cpp @@ -335,9 +335,51 @@ bool EvalScript(vector >& stack, const CScript& script, un // Control // case OP_NOP: - break; + break; - case OP_NOP1: case OP_NOP2: case OP_NOP3: case OP_NOP4: case OP_NOP5: + case OP_CHECKLOCKTIMEVERIFY: + { + if (!(flags & SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY)) { + // not enabled; treat as a NOP2 + if (flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS) { + return set_error(serror, SCRIPT_ERR_DISCOURAGE_UPGRADABLE_NOPS); + } + break; + } + + if (stack.size() < 1) + return set_error(serror, SCRIPT_ERR_INVALID_STACK_OPERATION); + + // Note that elsewhere numeric opcodes are limited to + // operands in the range -2**31+1 to 2**31-1, however it is + // legal for opcodes to produce results exceeding that + // range. This limitation is implemented by CScriptNum's + // default 4-byte limit. + // + // If we kept to that limit we'd have a year 2038 problem, + // even though the nLockTime field in transactions + // themselves is uint32 which only becomes meaningless + // after the year 2106. + // + // Thus as a special case we tell CScriptNum to accept up + // to 5-byte bignums, which are good until 2**39-1, well + // beyond the 2**32-1 limit of the nLockTime field itself. + const CScriptNum nLockTime(stacktop(-1), fRequireMinimal, 5); + + // In the rare event that the argument may be < 0 due to + // some arithmetic being done first, you can always use + // 0 MAX CHECKLOCKTIMEVERIFY. + if (nLockTime < 0) + return set_error(serror, SCRIPT_ERR_NEGATIVE_LOCKTIME); + + // Actually compare the specified lock time with the transaction. + if (!checker.CheckLockTime(nLockTime)) + return set_error(serror, SCRIPT_ERR_UNSATISFIED_LOCKTIME); + + break; + } + + case OP_NOP1: case OP_NOP3: case OP_NOP4: case OP_NOP5: case OP_NOP6: case OP_NOP7: case OP_NOP8: case OP_NOP9: case OP_NOP10: { if (flags & SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS) @@ -1084,6 +1126,43 @@ bool TransactionSignatureChecker::CheckSig(const vector& vchSigIn return true; } +bool TransactionSignatureChecker::CheckLockTime(const CScriptNum& nLockTime) const +{ + // There are two times of nLockTime: lock-by-blockheight + // and lock-by-blocktime, distinguished by whether + // nLockTime < LOCKTIME_THRESHOLD. + // + // We want to compare apples to apples, so fail the script + // unless the type of nLockTime being tested is the same as + // the nLockTime in the transaction. + if (!( + (txTo->nLockTime < LOCKTIME_THRESHOLD && nLockTime < LOCKTIME_THRESHOLD) || + (txTo->nLockTime >= LOCKTIME_THRESHOLD && nLockTime >= LOCKTIME_THRESHOLD) + )) + return false; + + // Now that we know we're comparing apples-to-apples, the + // comparison is a simple numeric one. + if (nLockTime > (int64_t)txTo->nLockTime) + return false; + + // Finally the nLockTime feature can be disabled and thus + // CHECKLOCKTIMEVERIFY bypassed if every txin has been + // finalized by setting nSequence to maxint. The + // transaction would be allowed into the blockchain, making + // the opcode ineffective. + // + // Testing if this vin is not final is sufficient to + // prevent this condition. Alternatively we could test all + // inputs, but testing just this input minimizes the data + // required to prove correct CHECKLOCKTIMEVERIFY execution. + if (txTo->vin[nIn].IsFinal()) + return false; + + return true; +} + + bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, unsigned int flags, const BaseSignatureChecker& checker, ScriptError* serror) { set_error(serror, SCRIPT_ERR_UNKNOWN_ERROR); diff --git a/src/script/interpreter.h b/src/script/interpreter.h index fc64438f68..35d572f0ad 100644 --- a/src/script/interpreter.h +++ b/src/script/interpreter.h @@ -76,6 +76,11 @@ enum // (softfork safe, BIP62 rule 6) // Note: CLEANSTACK should never be used without P2SH. SCRIPT_VERIFY_CLEANSTACK = (1U << 8), + + // Verify CHECKLOCKTIMEVERIFY + // + // See BIP65 for details. + SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY = (1U << 9), }; uint256 SignatureHash(const CScript &scriptCode, const CTransaction& txTo, unsigned int nIn, int nHashType); @@ -88,6 +93,11 @@ public: return false; } + virtual bool CheckLockTime(const CScriptNum& nLockTime) const + { + return false; + } + virtual ~BaseSignatureChecker() {} }; @@ -103,6 +113,7 @@ protected: public: TransactionSignatureChecker(const CTransaction* txToIn, unsigned int nInIn) : txTo(txToIn), nIn(nInIn) {} bool CheckSig(const std::vector& scriptSig, const std::vector& vchPubKey, const CScript& scriptCode) const; + bool CheckLockTime(const CScriptNum& nLockTime) const; }; class MutableTransactionSignatureChecker : public TransactionSignatureChecker diff --git a/src/script/script.h b/src/script/script.h index d5045005be..c09899aabd 100644 --- a/src/script/script.h +++ b/src/script/script.h @@ -19,6 +19,10 @@ static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes +// Threshold for nLockTime: below this value it is interpreted as block number, +// otherwise as UNIX timestamp. +static const unsigned int LOCKTIME_THRESHOLD = 500000000; // Tue Nov 5 00:53:20 1985 UTC + template std::vector ToByteVector(const T& in) { @@ -151,6 +155,7 @@ enum opcodetype // expansion OP_NOP1 = 0xb0, OP_NOP2 = 0xb1, + OP_CHECKLOCKTIMEVERIFY = OP_NOP2, OP_NOP3 = 0xb2, OP_NOP4 = 0xb3, OP_NOP5 = 0xb4, @@ -196,7 +201,10 @@ public: m_value = n; } - explicit CScriptNum(const std::vector& vch, bool fRequireMinimal) + static const size_t nDefaultMaxNumSize = 4; + + explicit CScriptNum(const std::vector& vch, bool fRequireMinimal, + const size_t nMaxNumSize = nDefaultMaxNumSize) { if (vch.size() > nMaxNumSize) { throw scriptnum_error("script number overflow"); @@ -319,8 +327,6 @@ public: return result; } - static const size_t nMaxNumSize = 4; - private: static int64_t set_vch(const std::vector& vch) { diff --git a/src/script/script_error.cpp b/src/script/script_error.cpp index d8ecfde1d7..f1aa1fb408 100644 --- a/src/script/script_error.cpp +++ b/src/script/script_error.cpp @@ -47,6 +47,10 @@ const char* ScriptErrorString(const ScriptError serror) return "OP_RETURN was encountered"; case SCRIPT_ERR_UNBALANCED_CONDITIONAL: return "Invalid OP_IF construction"; + case SCRIPT_ERR_NEGATIVE_LOCKTIME: + return "Negative locktime"; + case SCRIPT_ERR_UNSATISFIED_LOCKTIME: + return "Locktime requirement not satisfied"; case SCRIPT_ERR_SIG_HASHTYPE: return "Signature hash type missing or not understood"; case SCRIPT_ERR_SIG_DER: diff --git a/src/script/script_error.h b/src/script/script_error.h index 6365680b29..bb10b8a293 100644 --- a/src/script/script_error.h +++ b/src/script/script_error.h @@ -35,6 +35,10 @@ typedef enum ScriptError_t SCRIPT_ERR_INVALID_ALTSTACK_OPERATION, SCRIPT_ERR_UNBALANCED_CONDITIONAL, + /* OP_CHECKLOCKTIMEVERIFY */ + SCRIPT_ERR_NEGATIVE_LOCKTIME, + SCRIPT_ERR_UNSATISFIED_LOCKTIME, + /* BIP62 */ SCRIPT_ERR_SIG_HASHTYPE, SCRIPT_ERR_SIG_DER, diff --git a/src/script/standard.h b/src/script/standard.h index a8b0acc981..3b401dfe4f 100644 --- a/src/script/standard.h +++ b/src/script/standard.h @@ -50,7 +50,8 @@ static const unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY SCRIPT_VERIFY_MINIMALDATA | SCRIPT_VERIFY_NULLDUMMY | SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS | - SCRIPT_VERIFY_CLEANSTACK; + SCRIPT_VERIFY_CLEANSTACK | + SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY; /** For convenience, standard but not mandatory verify flags. */ static const unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS; diff --git a/src/test/data/tx_invalid.json b/src/test/data/tx_invalid.json index 31d33c63fb..9def4042da 100644 --- a/src/test/data/tx_invalid.json +++ b/src/test/data/tx_invalid.json @@ -120,6 +120,70 @@ [[["a955032f4d6b0c9bfe8cad8f00a8933790b9c1dc28c82e0f48e75b35da0e4944", 0, "IF CODESEPARATOR ENDIF 0x21 0x0378d430274f8c5ec1321338151e9f27f4c676a008bdf8638d07c0b6be9ab35c71 CHECKSIGVERIFY CODESEPARATOR 1"]], "010000000144490eda355be7480f2ec828dcc1b9903793a8008fad8cfe9b0c6b4d2f0355a9000000004a483045022100fa4a74ba9fd59c59f46c3960cf90cbe0d2b743c471d24a3d5d6db6002af5eebb02204d70ec490fd0f7055a7c45f86514336e3a7f03503dacecabb247fc23f15c83510100ffffffff010000000000000000016a00000000", "P2SH"], +["CHECKLOCKTIMEVERIFY tests"], + +["By-height locks, with argument just beyond tx nLockTime"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "1 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "499999999 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000fe64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], + +["By-time locks, with argument just beyond tx nLockTime (but within numerical boundries)"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000001 NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "4294967295 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000feffffff", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Argument missing"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Argument negative with by-blockheight nLockTime=0"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "-1 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Argument negative with by-blocktime nLockTime=500,000,000"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "-1 NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Input locked"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000ffffffff0100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Another input being unlocked isn't sufficient; the CHECKLOCKTIMEVERIFY-using input must be unlocked"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"] , + ["0000000000000000000000000000000000000000000000000000000000000200", 1, "1"]], +"010000000200010000000000000000000000000000000000000000000000000000000000000000000000ffffffff00020000000000000000000000000000000000000000000000000000000000000100000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Argument/tx height/time mismatch, both versions"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "499999999 NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000000 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000000 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ff64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Argument 2^32 with nLockTime=2^32-1"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "4294967296 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ffffffff", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Same, but with nLockTime=2^31-1"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "2147483648 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ffffff7f", "P2SH,CHECKLOCKTIMEVERIFY"], + +["6 byte non-minimally-encoded arguments are invalid even in their contents are valid"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0x06 0x000000000000 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Failure due to failing CHECKLOCKTIMEVERIFY in scriptSig"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000251b1000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Failure due to failing CHECKLOCKTIMEVERIFY in redeemScript"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "HASH160 0x14 0xc5b93064159b3b2d6ab506a41b1f50463771b988 EQUAL"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000030251b1000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], ["Make diffs cleaner by leaving a comment here without comma at the end"] ] diff --git a/src/test/data/tx_valid.json b/src/test/data/tx_valid.json index 182b88ef67..24fff575c1 100644 --- a/src/test/data/tx_valid.json +++ b/src/test/data/tx_valid.json @@ -187,5 +187,47 @@ "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", "P2SH"], +["CHECKLOCKTIMEVERIFY tests"], + +["By-height locks, with argument == 0 and == tx nLockTime"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "499999999 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ff64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ff64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], + +["By-time locks, with argument just beyond tx nLockTime (but within numerical boundries)"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000000 NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "4294967295 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ffffffff", "P2SH,CHECKLOCKTIMEVERIFY"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000000 NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ffffffff", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Any non-maxint nSequence is fine"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000feffffff0100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["The argument can be calculated rather than created directly by a PUSHDATA"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "499999999 1ADD NOP2 1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Perhaps even by an ADD producing a 5-byte result that is out of bounds for other opcodes"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "2147483647 2147483647 ADD NOP2 1"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000feffffff", "P2SH,CHECKLOCKTIMEVERIFY"], + +["5 byte non-minimally-encoded arguments are valid"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0x05 0x0000000000 NOP2 1"]], +"010000000100010000000000000000000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Valid CHECKLOCKTIMEVERIFY in scriptSig"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "1"]], +"01000000010001000000000000000000000000000000000000000000000000000000000000000000000251b1000000000100000000000000000001000000", "P2SH,CHECKLOCKTIMEVERIFY"], + +["Valid CHECKLOCKTIMEVERIFY in redeemScript"], +[[["0000000000000000000000000000000000000000000000000000000000000100", 0, "HASH160 0x14 0xc5b93064159b3b2d6ab506a41b1f50463771b988 EQUAL"]], +"0100000001000100000000000000000000000000000000000000000000000000000000000000000000030251b1000000000100000000000000000001000000", "P2SH,CHECKLOCKTIMEVERIFY"], + ["Make diffs cleaner by leaving a comment here without comma at the end"] ] diff --git a/src/test/scriptnum_tests.cpp b/src/test/scriptnum_tests.cpp index 24c7dd3d5a..d95724dbe1 100644 --- a/src/test/scriptnum_tests.cpp +++ b/src/test/scriptnum_tests.cpp @@ -145,7 +145,7 @@ static void RunCreate(const int64_t& num) { CheckCreateInt(num); CScriptNum scriptnum(num); - if (scriptnum.getvch().size() <= CScriptNum::nMaxNumSize) + if (scriptnum.getvch().size() <= CScriptNum::nDefaultMaxNumSize) CheckCreateVch(num); else { diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp index 4cfdec1267..9ce7aae966 100644 --- a/src/test/transaction_tests.cpp +++ b/src/test/transaction_tests.cpp @@ -41,7 +41,8 @@ static std::map mapFlagNames = boost::assign::map_list_of (string("MINIMALDATA"), (unsigned int)SCRIPT_VERIFY_MINIMALDATA) (string("NULLDUMMY"), (unsigned int)SCRIPT_VERIFY_NULLDUMMY) (string("DISCOURAGE_UPGRADABLE_NOPS"), (unsigned int)SCRIPT_VERIFY_DISCOURAGE_UPGRADABLE_NOPS) - (string("CLEANSTACK"), (unsigned int)SCRIPT_VERIFY_CLEANSTACK); + (string("CLEANSTACK"), (unsigned int)SCRIPT_VERIFY_CLEANSTACK) + (string("CHECKLOCKTIMEVERIFY"), (unsigned int)SCRIPT_VERIFY_CHECKLOCKTIMEVERIFY); unsigned int ParseScriptFlags(string strFlags) {