diff options
author | Wladimir J. van der Laan <laanwj@gmail.com> | 2014-05-09 16:02:40 +0200 |
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committer | Wladimir J. van der Laan <laanwj@gmail.com> | 2014-05-09 16:03:07 +0200 |
commit | 1c0319bb2ba227b67a10563ae5c9f65f4358c472 (patch) | |
tree | 09b1bef60a135c1546d3a3028f74cb56d0227979 /src/script.h | |
parent | d54985f3f1385481696dbc53bce4aa3c0205a597 (diff) | |
parent | b1fdd5475d9040445d7655730f262f214ea87c5f (diff) |
Merge pull request #3965
b1fdd54 script: Add test for CScriptNum (Cory Fields)
90320d6 script: add additional script tests (Cory Fields)
05e3ecf script: remove bignum dependency (Cory Fields)
4f497cd script: switch outside users to CScriptNum (Cory Fields)
27bff74 script: switch to CScriptNum usage for scripts (Cory Fields)
48d8eb1 script: add CScriptNum class (Cory Fields)
Diffstat (limited to 'src/script.h')
-rw-r--r-- | src/script.h | 198 |
1 files changed, 155 insertions, 43 deletions
diff --git a/src/script.h b/src/script.h index 657ac0b388..1742ce81f8 100644 --- a/src/script.h +++ b/src/script.h @@ -6,7 +6,6 @@ #ifndef H_BITCOIN_SCRIPT #define H_BITCOIN_SCRIPT -#include "bignum.h" #include "key.h" #include "util.h" @@ -25,6 +24,155 @@ class CTransaction; static const unsigned int MAX_SCRIPT_ELEMENT_SIZE = 520; // bytes static const unsigned int MAX_OP_RETURN_RELAY = 40; // bytes +class scriptnum_error : public std::runtime_error +{ +public: + explicit scriptnum_error(const std::string& str) : std::runtime_error(str) {} +}; + +class CScriptNum +{ +// Numeric opcodes (OP_1ADD, etc) are restricted to operating on 4-byte integers. +// The semantics are subtle, though: operands must be in the range [-2^31 +1...2^31 -1], +// but results may overflow (and are valid as long as they are not used in a subsequent +// numeric operation). CScriptNum enforces those semantics by storing results as +// an int64 and allowing out-of-range values to be returned as a vector of bytes but +// throwing an exception if arithmetic is done or the result is interpreted as an integer. +public: + + explicit CScriptNum(const int64_t& n) + { + m_value = n; + } + + explicit CScriptNum(const std::vector<unsigned char>& vch) + { + if (vch.size() > nMaxNumSize) + throw scriptnum_error("CScriptNum(const std::vector<unsigned char>&) : overflow"); + m_value = set_vch(vch); + } + + inline bool operator==(const int64_t& rhs) const { return m_value == rhs; } + inline bool operator!=(const int64_t& rhs) const { return m_value != rhs; } + inline bool operator<=(const int64_t& rhs) const { return m_value <= rhs; } + inline bool operator< (const int64_t& rhs) const { return m_value < rhs; } + inline bool operator>=(const int64_t& rhs) const { return m_value >= rhs; } + inline bool operator> (const int64_t& rhs) const { return m_value > rhs; } + + inline bool operator==(const CScriptNum& rhs) const { return operator==(rhs.m_value); } + inline bool operator!=(const CScriptNum& rhs) const { return operator!=(rhs.m_value); } + inline bool operator<=(const CScriptNum& rhs) const { return operator<=(rhs.m_value); } + inline bool operator< (const CScriptNum& rhs) const { return operator< (rhs.m_value); } + inline bool operator>=(const CScriptNum& rhs) const { return operator>=(rhs.m_value); } + inline bool operator> (const CScriptNum& rhs) const { return operator> (rhs.m_value); } + + inline CScriptNum operator+( const int64_t& rhs) const { return CScriptNum(m_value + rhs);} + inline CScriptNum operator-( const int64_t& rhs) const { return CScriptNum(m_value - rhs);} + inline CScriptNum operator+( const CScriptNum& rhs) const { return operator+(rhs.m_value); } + inline CScriptNum operator-( const CScriptNum& rhs) const { return operator-(rhs.m_value); } + + inline CScriptNum& operator+=( const CScriptNum& rhs) { return operator+=(rhs.m_value); } + inline CScriptNum& operator-=( const CScriptNum& rhs) { return operator-=(rhs.m_value); } + + inline CScriptNum operator-() const + { + assert(m_value != std::numeric_limits<int64_t>::min()); + return CScriptNum(-m_value); + } + + inline CScriptNum& operator=( const int64_t& rhs) + { + m_value = rhs; + return *this; + } + + inline CScriptNum& operator+=( const int64_t& rhs) + { + assert(rhs == 0 || (rhs > 0 && m_value <= std::numeric_limits<int64_t>::max() - rhs) || + (rhs < 0 && m_value >= std::numeric_limits<int64_t>::min() - rhs)); + m_value += rhs; + return *this; + } + + inline CScriptNum& operator-=( const int64_t& rhs) + { + assert(rhs == 0 || (rhs > 0 && m_value >= std::numeric_limits<int64_t>::min() + rhs) || + (rhs < 0 && m_value <= std::numeric_limits<int64_t>::max() + rhs)); + m_value -= rhs; + return *this; + } + + int getint() const + { + if (m_value > std::numeric_limits<int>::max()) + return std::numeric_limits<int>::max(); + else if (m_value < std::numeric_limits<int>::min()) + return std::numeric_limits<int>::min(); + return m_value; + } + + std::vector<unsigned char> getvch() const + { + return serialize(m_value); + } + + static std::vector<unsigned char> serialize(const int64_t& value) + { + if(value == 0) + return std::vector<unsigned char>(); + + std::vector<unsigned char> result; + const bool neg = value < 0; + uint64_t absvalue = neg ? -value : value; + + while(absvalue) + { + result.push_back(absvalue & 0xff); + absvalue >>= 8; + } + + +// - If the most significant byte is >= 0x80 and the value is positive, push a +// new zero-byte to make the significant byte < 0x80 again. + +// - If the most significant byte is >= 0x80 and the value is negative, push a +// new 0x80 byte that will be popped off when converting to an integral. + +// - If the most significant byte is < 0x80 and the value is negative, add +// 0x80 to it, since it will be subtracted and interpreted as a negative when +// converting to an integral. + + if (result.back() & 0x80) + result.push_back(neg ? 0x80 : 0); + else if (neg) + result.back() |= 0x80; + + return result; + } + + static const size_t nMaxNumSize = 4; + +private: + static int64_t set_vch(const std::vector<unsigned char>& vch) + { + if (vch.empty()) + return 0; + + int64_t result = 0; + for (size_t i = 0; i != vch.size(); ++i) + result |= static_cast<int64_t>(vch[i]) << 8*i; + + // If the input vector's most significant byte is 0x80, remove it from + // the result's msb and return a negative. + if (vch.back() & 0x80) + return -(result & ~(0x80 << (8 * (vch.size() - 1)))); + + return result; + } + + int64_t m_value; +}; + /** Signature hash types/flags */ enum { @@ -225,7 +373,7 @@ const char* GetOpName(opcodetype opcode); inline std::string ValueString(const std::vector<unsigned char>& vch) { if (vch.size() <= 4) - return strprintf("%d", CBigNum(vch).getint()); + return strprintf("%d", CScriptNum(vch).getint()); else return HexStr(vch); } @@ -261,26 +409,10 @@ protected: } else { - CBigNum bn(n); - *this << bn.getvch(); + *this << CScriptNum::serialize(n); } return *this; } - - CScript& push_uint64(uint64_t n) - { - if (n >= 1 && n <= 16) - { - push_back(n + (OP_1 - 1)); - } - else - { - CBigNum bn(n); - *this << bn.getvch(); - } - return *this; - } - public: CScript() { } CScript(const CScript& b) : std::vector<unsigned char>(b.begin(), b.end()) { } @@ -303,35 +435,15 @@ public: } - //explicit CScript(char b) is not portable. Use 'signed char' or 'unsigned char'. - explicit CScript(signed char b) { operator<<(b); } - explicit CScript(short b) { operator<<(b); } - explicit CScript(int b) { operator<<(b); } - explicit CScript(long b) { operator<<(b); } - explicit CScript(long long b) { operator<<(b); } - explicit CScript(unsigned char b) { operator<<(b); } - explicit CScript(unsigned int b) { operator<<(b); } - explicit CScript(unsigned short b) { operator<<(b); } - explicit CScript(unsigned long b) { operator<<(b); } - explicit CScript(unsigned long long b) { operator<<(b); } + CScript(int64_t b) { operator<<(b); } explicit CScript(opcodetype b) { operator<<(b); } explicit CScript(const uint256& b) { operator<<(b); } - explicit CScript(const CBigNum& b) { operator<<(b); } + explicit CScript(const CScriptNum& b) { operator<<(b); } explicit CScript(const std::vector<unsigned char>& b) { operator<<(b); } - //CScript& operator<<(char b) is not portable. Use 'signed char' or 'unsigned char'. - CScript& operator<<(signed char b) { return push_int64(b); } - CScript& operator<<(short b) { return push_int64(b); } - CScript& operator<<(int b) { return push_int64(b); } - CScript& operator<<(long b) { return push_int64(b); } - CScript& operator<<(long long b) { return push_int64(b); } - CScript& operator<<(unsigned char b) { return push_uint64(b); } - CScript& operator<<(unsigned int b) { return push_uint64(b); } - CScript& operator<<(unsigned short b) { return push_uint64(b); } - CScript& operator<<(unsigned long b) { return push_uint64(b); } - CScript& operator<<(unsigned long long b) { return push_uint64(b); } + CScript& operator<<(int64_t b) { return push_int64(b); } CScript& operator<<(opcodetype opcode) { @@ -363,7 +475,7 @@ public: return *this; } - CScript& operator<<(const CBigNum& b) + CScript& operator<<(const CScriptNum& b) { *this << b.getvch(); return *this; |