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Diffstat (limited to 'src/bignum.h')
| -rw-r--r-- | src/bignum.h | 595 |
1 files changed, 0 insertions, 595 deletions
diff --git a/src/bignum.h b/src/bignum.h deleted file mode 100644 index 0259338b31..0000000000 --- a/src/bignum.h +++ /dev/null @@ -1,595 +0,0 @@ -// Copyright (c) 2009-2010 Satoshi Nakamoto -// Copyright (c) 2009-2013 The Bitcoin developers -// Distributed under the MIT/X11 software license, see the accompanying -// file COPYING or http://www.opensource.org/licenses/mit-license.php. - -#ifndef BITCOIN_BIGNUM_H -#define BITCOIN_BIGNUM_H - -#include "serialize.h" -#include "uint256.h" -#include "version.h" - -#include <stdexcept> -#include <stdint.h> -#include <vector> - -#include <openssl/bn.h> - -/** Errors thrown by the bignum class */ -class bignum_error : public std::runtime_error -{ -public: - explicit bignum_error(const std::string& str) : std::runtime_error(str) {} -}; - - -/** RAII encapsulated BN_CTX (OpenSSL bignum context) */ -class CAutoBN_CTX -{ -protected: - BN_CTX* pctx; - BN_CTX* operator=(BN_CTX* pnew) { return pctx = pnew; } - -public: - CAutoBN_CTX() - { - pctx = BN_CTX_new(); - if (pctx == NULL) - throw bignum_error("CAutoBN_CTX : BN_CTX_new() returned NULL"); - } - - ~CAutoBN_CTX() - { - if (pctx != NULL) - BN_CTX_free(pctx); - } - - operator BN_CTX*() { return pctx; } - BN_CTX& operator*() { return *pctx; } - BN_CTX** operator&() { return &pctx; } - bool operator!() { return (pctx == NULL); } -}; - - -/** C++ wrapper for BIGNUM (OpenSSL bignum) */ -class CBigNum : public BIGNUM -{ -public: - CBigNum() - { - BN_init(this); - } - - CBigNum(const CBigNum& b) - { - BN_init(this); - if (!BN_copy(this, &b)) - { - BN_clear_free(this); - throw bignum_error("CBigNum::CBigNum(const CBigNum&) : BN_copy failed"); - } - } - - CBigNum& operator=(const CBigNum& b) - { - if (!BN_copy(this, &b)) - throw bignum_error("CBigNum::operator= : BN_copy failed"); - return (*this); - } - - ~CBigNum() - { - BN_clear_free(this); - } - - //CBigNum(char n) is not portable. Use 'signed char' or 'unsigned char'. - CBigNum(signed char n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); } - CBigNum(short n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); } - CBigNum(int n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); } - CBigNum(long n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); } - CBigNum(long long n) { BN_init(this); setint64(n); } - CBigNum(unsigned char n) { BN_init(this); setulong(n); } - CBigNum(unsigned short n) { BN_init(this); setulong(n); } - CBigNum(unsigned int n) { BN_init(this); setulong(n); } - CBigNum(unsigned long n) { BN_init(this); setulong(n); } - CBigNum(unsigned long long n) { BN_init(this); setuint64(n); } - explicit CBigNum(uint256 n) { BN_init(this); setuint256(n); } - - explicit CBigNum(const std::vector<unsigned char>& vch) - { - BN_init(this); - setvch(vch); - } - - void setulong(unsigned long n) - { - if (!BN_set_word(this, n)) - throw bignum_error("CBigNum conversion from unsigned long : BN_set_word failed"); - } - - unsigned long getulong() const - { - return BN_get_word(this); - } - - unsigned int getuint() const - { - return BN_get_word(this); - } - - int getint() const - { - unsigned long n = BN_get_word(this); - if (!BN_is_negative(this)) - return (n > (unsigned long)std::numeric_limits<int>::max() ? std::numeric_limits<int>::max() : n); - else - return (n > (unsigned long)std::numeric_limits<int>::max() ? std::numeric_limits<int>::min() : -(int)n); - } - - void setint64(int64_t sn) - { - unsigned char pch[sizeof(sn) + 6]; - unsigned char* p = pch + 4; - bool fNegative; - uint64_t n; - - if (sn < (int64_t)0) - { - // Since the minimum signed integer cannot be represented as positive so long as its type is signed, - // and it's not well-defined what happens if you make it unsigned before negating it, - // we instead increment the negative integer by 1, convert it, then increment the (now positive) unsigned integer by 1 to compensate - n = -(sn + 1); - ++n; - fNegative = true; - } else { - n = sn; - fNegative = false; - } - - bool fLeadingZeroes = true; - for (int i = 0; i < 8; i++) - { - unsigned char c = (n >> 56) & 0xff; - n <<= 8; - if (fLeadingZeroes) - { - if (c == 0) - continue; - if (c & 0x80) - *p++ = (fNegative ? 0x80 : 0); - else if (fNegative) - c |= 0x80; - fLeadingZeroes = false; - } - *p++ = c; - } - unsigned int nSize = p - (pch + 4); - pch[0] = (nSize >> 24) & 0xff; - pch[1] = (nSize >> 16) & 0xff; - pch[2] = (nSize >> 8) & 0xff; - pch[3] = (nSize) & 0xff; - BN_mpi2bn(pch, p - pch, this); - } - - void setuint64(uint64_t n) - { - unsigned char pch[sizeof(n) + 6]; - unsigned char* p = pch + 4; - bool fLeadingZeroes = true; - for (int i = 0; i < 8; i++) - { - unsigned char c = (n >> 56) & 0xff; - n <<= 8; - if (fLeadingZeroes) - { - if (c == 0) - continue; - if (c & 0x80) - *p++ = 0; - fLeadingZeroes = false; - } - *p++ = c; - } - unsigned int nSize = p - (pch + 4); - pch[0] = (nSize >> 24) & 0xff; - pch[1] = (nSize >> 16) & 0xff; - pch[2] = (nSize >> 8) & 0xff; - pch[3] = (nSize) & 0xff; - BN_mpi2bn(pch, p - pch, this); - } - - void setuint256(uint256 n) - { - unsigned char pch[sizeof(n) + 6]; - unsigned char* p = pch + 4; - bool fLeadingZeroes = true; - unsigned char* pbegin = (unsigned char*)&n; - unsigned char* psrc = pbegin + sizeof(n); - while (psrc != pbegin) - { - unsigned char c = *(--psrc); - if (fLeadingZeroes) - { - if (c == 0) - continue; - if (c & 0x80) - *p++ = 0; - fLeadingZeroes = false; - } - *p++ = c; - } - unsigned int nSize = p - (pch + 4); - pch[0] = (nSize >> 24) & 0xff; - pch[1] = (nSize >> 16) & 0xff; - pch[2] = (nSize >> 8) & 0xff; - pch[3] = (nSize >> 0) & 0xff; - BN_mpi2bn(pch, p - pch, this); - } - - uint256 getuint256() const - { - unsigned int nSize = BN_bn2mpi(this, NULL); - if (nSize < 4) - return 0; - std::vector<unsigned char> vch(nSize); - BN_bn2mpi(this, &vch[0]); - if (vch.size() > 4) - vch[4] &= 0x7f; - uint256 n = 0; - for (unsigned int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--) - ((unsigned char*)&n)[i] = vch[j]; - return n; - } - - void setvch(const std::vector<unsigned char>& vch) - { - std::vector<unsigned char> vch2(vch.size() + 4); - unsigned int nSize = vch.size(); - // BIGNUM's byte stream format expects 4 bytes of - // big endian size data info at the front - vch2[0] = (nSize >> 24) & 0xff; - vch2[1] = (nSize >> 16) & 0xff; - vch2[2] = (nSize >> 8) & 0xff; - vch2[3] = (nSize >> 0) & 0xff; - // swap data to big endian - reverse_copy(vch.begin(), vch.end(), vch2.begin() + 4); - BN_mpi2bn(&vch2[0], vch2.size(), this); - } - - std::vector<unsigned char> getvch() const - { - unsigned int nSize = BN_bn2mpi(this, NULL); - if (nSize <= 4) - return std::vector<unsigned char>(); - std::vector<unsigned char> vch(nSize); - BN_bn2mpi(this, &vch[0]); - vch.erase(vch.begin(), vch.begin() + 4); - reverse(vch.begin(), vch.end()); - return vch; - } - - // The "compact" format is a representation of a whole - // number N using an unsigned 32bit number similar to a - // floating point format. - // The most significant 8 bits are the unsigned exponent of base 256. - // This exponent can be thought of as "number of bytes of N". - // The lower 23 bits are the mantissa. - // Bit number 24 (0x800000) represents the sign of N. - // N = (-1^sign) * mantissa * 256^(exponent-3) - // - // Satoshi's original implementation used BN_bn2mpi() and BN_mpi2bn(). - // MPI uses the most significant bit of the first byte as sign. - // Thus 0x1234560000 is compact (0x05123456) - // and 0xc0de000000 is compact (0x0600c0de) - // (0x05c0de00) would be -0x40de000000 - // - // Bitcoin only uses this "compact" format for encoding difficulty - // targets, which are unsigned 256bit quantities. Thus, all the - // complexities of the sign bit and using base 256 are probably an - // implementation accident. - // - // This implementation directly uses shifts instead of going - // through an intermediate MPI representation. - CBigNum& SetCompact(unsigned int nCompact) - { - unsigned int nSize = nCompact >> 24; - bool fNegative =(nCompact & 0x00800000) != 0; - unsigned int nWord = nCompact & 0x007fffff; - if (nSize <= 3) - { - nWord >>= 8*(3-nSize); - BN_set_word(this, nWord); - } - else - { - BN_set_word(this, nWord); - BN_lshift(this, this, 8*(nSize-3)); - } - BN_set_negative(this, fNegative); - return *this; - } - - unsigned int GetCompact() const - { - unsigned int nSize = BN_num_bytes(this); - unsigned int nCompact = 0; - if (nSize <= 3) - nCompact = BN_get_word(this) << 8*(3-nSize); - else - { - CBigNum bn; - BN_rshift(&bn, this, 8*(nSize-3)); - nCompact = BN_get_word(&bn); - } - // The 0x00800000 bit denotes the sign. - // Thus, if it is already set, divide the mantissa by 256 and increase the exponent. - if (nCompact & 0x00800000) - { - nCompact >>= 8; - nSize++; - } - nCompact |= nSize << 24; - nCompact |= (BN_is_negative(this) ? 0x00800000 : 0); - return nCompact; - } - - void SetHex(const std::string& str) - { - // skip 0x - const char* psz = str.c_str(); - while (isspace(*psz)) - psz++; - bool fNegative = false; - if (*psz == '-') - { - fNegative = true; - psz++; - } - if (psz[0] == '0' && tolower(psz[1]) == 'x') - psz += 2; - while (isspace(*psz)) - psz++; - - // hex string to bignum - *this = 0; - int n; - while ((n = HexDigit(*psz)) != -1) - { - *this <<= 4; - *this += n; - ++psz; - } - if (fNegative) - *this = 0 - *this; - } - - std::string ToString(int nBase=10) const - { - CAutoBN_CTX pctx; - CBigNum bnBase = nBase; - CBigNum bn0 = 0; - std::string str; - CBigNum bn = *this; - BN_set_negative(&bn, false); - CBigNum dv; - CBigNum rem; - if (BN_cmp(&bn, &bn0) == 0) - return "0"; - while (BN_cmp(&bn, &bn0) > 0) - { - if (!BN_div(&dv, &rem, &bn, &bnBase, pctx)) - throw bignum_error("CBigNum::ToString() : BN_div failed"); - bn = dv; - unsigned int c = rem.getulong(); - str += "0123456789abcdef"[c]; - } - if (BN_is_negative(this)) - str += "-"; - reverse(str.begin(), str.end()); - return str; - } - - std::string GetHex() const - { - return ToString(16); - } - - unsigned int GetSerializeSize(int nType=0, int nVersion=PROTOCOL_VERSION) const - { - return ::GetSerializeSize(getvch(), nType, nVersion); - } - - template<typename Stream> - void Serialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) const - { - ::Serialize(s, getvch(), nType, nVersion); - } - - template<typename Stream> - void Unserialize(Stream& s, int nType=0, int nVersion=PROTOCOL_VERSION) - { - std::vector<unsigned char> vch; - ::Unserialize(s, vch, nType, nVersion); - setvch(vch); - } - - - bool operator!() const - { - return BN_is_zero(this); - } - - CBigNum& operator+=(const CBigNum& b) - { - if (!BN_add(this, this, &b)) - throw bignum_error("CBigNum::operator+= : BN_add failed"); - return *this; - } - - CBigNum& operator-=(const CBigNum& b) - { - *this = *this - b; - return *this; - } - - CBigNum& operator*=(const CBigNum& b) - { - CAutoBN_CTX pctx; - if (!BN_mul(this, this, &b, pctx)) - throw bignum_error("CBigNum::operator*= : BN_mul failed"); - return *this; - } - - CBigNum& operator/=(const CBigNum& b) - { - *this = *this / b; - return *this; - } - - CBigNum& operator%=(const CBigNum& b) - { - *this = *this % b; - return *this; - } - - CBigNum& operator<<=(unsigned int shift) - { - if (!BN_lshift(this, this, shift)) - throw bignum_error("CBigNum:operator<<= : BN_lshift failed"); - return *this; - } - - CBigNum& operator>>=(unsigned int shift) - { - // Note: BN_rshift segfaults on 64-bit if 2^shift is greater than the number - // if built on ubuntu 9.04 or 9.10, probably depends on version of OpenSSL - CBigNum a = 1; - a <<= shift; - if (BN_cmp(&a, this) > 0) - { - *this = 0; - return *this; - } - - if (!BN_rshift(this, this, shift)) - throw bignum_error("CBigNum:operator>>= : BN_rshift failed"); - return *this; - } - - - CBigNum& operator++() - { - // prefix operator - if (!BN_add(this, this, BN_value_one())) - throw bignum_error("CBigNum::operator++ : BN_add failed"); - return *this; - } - - const CBigNum operator++(int) - { - // postfix operator - const CBigNum ret = *this; - ++(*this); - return ret; - } - - CBigNum& operator--() - { - // prefix operator - CBigNum r; - if (!BN_sub(&r, this, BN_value_one())) - throw bignum_error("CBigNum::operator-- : BN_sub failed"); - *this = r; - return *this; - } - - const CBigNum operator--(int) - { - // postfix operator - const CBigNum ret = *this; - --(*this); - return ret; - } - - - friend inline const CBigNum operator-(const CBigNum& a, const CBigNum& b); - friend inline const CBigNum operator/(const CBigNum& a, const CBigNum& b); - friend inline const CBigNum operator%(const CBigNum& a, const CBigNum& b); -}; - - - -inline const CBigNum operator+(const CBigNum& a, const CBigNum& b) -{ - CBigNum r; - if (!BN_add(&r, &a, &b)) - throw bignum_error("CBigNum::operator+ : BN_add failed"); - return r; -} - -inline const CBigNum operator-(const CBigNum& a, const CBigNum& b) -{ - CBigNum r; - if (!BN_sub(&r, &a, &b)) - throw bignum_error("CBigNum::operator- : BN_sub failed"); - return r; -} - -inline const CBigNum operator-(const CBigNum& a) -{ - CBigNum r(a); - BN_set_negative(&r, !BN_is_negative(&r)); - return r; -} - -inline const CBigNum operator*(const CBigNum& a, const CBigNum& b) -{ - CAutoBN_CTX pctx; - CBigNum r; - if (!BN_mul(&r, &a, &b, pctx)) - throw bignum_error("CBigNum::operator* : BN_mul failed"); - return r; -} - -inline const CBigNum operator/(const CBigNum& a, const CBigNum& b) -{ - CAutoBN_CTX pctx; - CBigNum r; - if (!BN_div(&r, NULL, &a, &b, pctx)) - throw bignum_error("CBigNum::operator/ : BN_div failed"); - return r; -} - -inline const CBigNum operator%(const CBigNum& a, const CBigNum& b) -{ - CAutoBN_CTX pctx; - CBigNum r; - if (!BN_mod(&r, &a, &b, pctx)) - throw bignum_error("CBigNum::operator% : BN_div failed"); - return r; -} - -inline const CBigNum operator<<(const CBigNum& a, unsigned int shift) -{ - CBigNum r; - if (!BN_lshift(&r, &a, shift)) - throw bignum_error("CBigNum:operator<< : BN_lshift failed"); - return r; -} - -inline const CBigNum operator>>(const CBigNum& a, unsigned int shift) -{ - CBigNum r = a; - r >>= shift; - return r; -} - -inline bool operator==(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) == 0); } -inline bool operator!=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) != 0); } -inline bool operator<=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) <= 0); } -inline bool operator>=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) >= 0); } -inline bool operator<(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) < 0); } -inline bool operator>(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) > 0); } - -#endif |