1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file license.txt or http://www.opensource.org/licenses/mit-license.php.
4 #ifndef BITCOIN_BIGNUM_H
5 #define BITCOIN_BIGNUM_H
9 #include <openssl/bn.h>
13 class bignum_error : public std::runtime_error
16 explicit bignum_error(const std::string& str) : std::runtime_error(str) {}
25 BN_CTX* operator=(BN_CTX* pnew) { return pctx = pnew; }
32 throw bignum_error("CAutoBN_CTX : BN_CTX_new() returned NULL");
41 operator BN_CTX*() { return pctx; }
42 BN_CTX& operator*() { return *pctx; }
43 BN_CTX** operator&() { return &pctx; }
44 bool operator!() { return (pctx == NULL); }
49 class CBigNum : public BIGNUM
57 CBigNum(const CBigNum& b)
60 if (!BN_copy(this, &b))
63 throw bignum_error("CBigNum::CBigNum(const CBigNum&) : BN_copy failed");
67 CBigNum& operator=(const CBigNum& b)
69 if (!BN_copy(this, &b))
70 throw bignum_error("CBigNum::operator= : BN_copy failed");
79 CBigNum(char n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
80 CBigNum(short n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
81 CBigNum(int n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
82 CBigNum(long n) { BN_init(this); if (n >= 0) setulong(n); else setint64(n); }
83 CBigNum(int64 n) { BN_init(this); setint64(n); }
84 CBigNum(unsigned char n) { BN_init(this); setulong(n); }
85 CBigNum(unsigned short n) { BN_init(this); setulong(n); }
86 CBigNum(unsigned int n) { BN_init(this); setulong(n); }
87 CBigNum(unsigned long n) { BN_init(this); setulong(n); }
88 CBigNum(uint64 n) { BN_init(this); setuint64(n); }
89 explicit CBigNum(uint256 n) { BN_init(this); setuint256(n); }
91 explicit CBigNum(const std::vector<unsigned char>& vch)
97 void setulong(unsigned long n)
99 if (!BN_set_word(this, n))
100 throw bignum_error("CBigNum conversion from unsigned long : BN_set_word failed");
103 unsigned long getulong() const
105 return BN_get_word(this);
108 unsigned int getuint() const
110 return BN_get_word(this);
115 unsigned long n = BN_get_word(this);
116 if (!BN_is_negative(this))
117 return (n > INT_MAX ? INT_MAX : n);
119 return (n > INT_MAX ? INT_MIN : -(int)n);
122 void setint64(int64 n)
124 unsigned char pch[sizeof(n) + 6];
125 unsigned char* p = pch + 4;
126 bool fNegative = false;
132 bool fLeadingZeroes = true;
133 for (int i = 0; i < 8; i++)
135 unsigned char c = (n >> 56) & 0xff;
142 *p++ = (fNegative ? 0x80 : 0);
145 fLeadingZeroes = false;
149 unsigned int nSize = p - (pch + 4);
150 pch[0] = (nSize >> 24) & 0xff;
151 pch[1] = (nSize >> 16) & 0xff;
152 pch[2] = (nSize >> 8) & 0xff;
153 pch[3] = (nSize) & 0xff;
154 BN_mpi2bn(pch, p - pch, this);
157 void setuint64(uint64 n)
159 unsigned char pch[sizeof(n) + 6];
160 unsigned char* p = pch + 4;
161 bool fLeadingZeroes = true;
162 for (int i = 0; i < 8; i++)
164 unsigned char c = (n >> 56) & 0xff;
172 fLeadingZeroes = false;
176 unsigned int nSize = p - (pch + 4);
177 pch[0] = (nSize >> 24) & 0xff;
178 pch[1] = (nSize >> 16) & 0xff;
179 pch[2] = (nSize >> 8) & 0xff;
180 pch[3] = (nSize) & 0xff;
181 BN_mpi2bn(pch, p - pch, this);
184 void setuint256(uint256 n)
186 unsigned char pch[sizeof(n) + 6];
187 unsigned char* p = pch + 4;
188 bool fLeadingZeroes = true;
189 unsigned char* pbegin = (unsigned char*)&n;
190 unsigned char* psrc = pbegin + sizeof(n);
191 while (psrc != pbegin)
193 unsigned char c = *(--psrc);
200 fLeadingZeroes = false;
204 unsigned int nSize = p - (pch + 4);
205 pch[0] = (nSize >> 24) & 0xff;
206 pch[1] = (nSize >> 16) & 0xff;
207 pch[2] = (nSize >> 8) & 0xff;
208 pch[3] = (nSize >> 0) & 0xff;
209 BN_mpi2bn(pch, p - pch, this);
214 unsigned int nSize = BN_bn2mpi(this, NULL);
217 std::vector<unsigned char> vch(nSize);
218 BN_bn2mpi(this, &vch[0]);
222 for (int i = 0, j = vch.size()-1; i < sizeof(n) && j >= 4; i++, j--)
223 ((unsigned char*)&n)[i] = vch[j];
227 void setvch(const std::vector<unsigned char>& vch)
229 std::vector<unsigned char> vch2(vch.size() + 4);
230 unsigned int nSize = vch.size();
231 // BIGNUM's byte stream format expects 4 bytes of
232 // big endian size data info at the front
233 vch2[0] = (nSize >> 24) & 0xff;
234 vch2[1] = (nSize >> 16) & 0xff;
235 vch2[2] = (nSize >> 8) & 0xff;
236 vch2[3] = (nSize >> 0) & 0xff;
237 // swap data to big endian
238 reverse_copy(vch.begin(), vch.end(), vch2.begin() + 4);
239 BN_mpi2bn(&vch2[0], vch2.size(), this);
242 std::vector<unsigned char> getvch() const
244 unsigned int nSize = BN_bn2mpi(this, NULL);
246 return std::vector<unsigned char>();
247 std::vector<unsigned char> vch(nSize);
248 BN_bn2mpi(this, &vch[0]);
249 vch.erase(vch.begin(), vch.begin() + 4);
250 reverse(vch.begin(), vch.end());
254 CBigNum& SetCompact(unsigned int nCompact)
256 unsigned int nSize = nCompact >> 24;
257 std::vector<unsigned char> vch(4 + nSize);
259 if (nSize >= 1) vch[4] = (nCompact >> 16) & 0xff;
260 if (nSize >= 2) vch[5] = (nCompact >> 8) & 0xff;
261 if (nSize >= 3) vch[6] = (nCompact >> 0) & 0xff;
262 BN_mpi2bn(&vch[0], vch.size(), this);
266 unsigned int GetCompact() const
268 unsigned int nSize = BN_bn2mpi(this, NULL);
269 std::vector<unsigned char> vch(nSize);
271 BN_bn2mpi(this, &vch[0]);
272 unsigned int nCompact = nSize << 24;
273 if (nSize >= 1) nCompact |= (vch[4] << 16);
274 if (nSize >= 2) nCompact |= (vch[5] << 8);
275 if (nSize >= 3) nCompact |= (vch[6] << 0);
279 void SetHex(const std::string& str)
282 const char* psz = str.c_str();
283 while (isspace(*psz))
285 bool fNegative = false;
291 if (psz[0] == '0' && tolower(psz[1]) == 'x')
293 while (isspace(*psz))
296 // hex string to bignum
297 static char phexdigit[256] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,1,2,3,4,5,6,7,8,9,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0xa,0xb,0xc,0xd,0xe,0xf,0,0,0,0,0,0,0,0,0 };
299 while (isxdigit(*psz))
302 int n = phexdigit[*psz++];
309 std::string ToString(int nBase=10) const
312 CBigNum bnBase = nBase;
316 BN_set_negative(&bn, false);
319 if (BN_cmp(&bn, &bn0) == 0)
321 while (BN_cmp(&bn, &bn0) > 0)
323 if (!BN_div(&dv, &rem, &bn, &bnBase, pctx))
324 throw bignum_error("CBigNum::ToString() : BN_div failed");
326 unsigned int c = rem.getulong();
327 str += "0123456789abcdef"[c];
329 if (BN_is_negative(this))
331 reverse(str.begin(), str.end());
335 std::string GetHex() const
340 unsigned int GetSerializeSize(int nType=0, int nVersion=VERSION) const
342 return ::GetSerializeSize(getvch(), nType, nVersion);
345 template<typename Stream>
346 void Serialize(Stream& s, int nType=0, int nVersion=VERSION) const
348 ::Serialize(s, getvch(), nType, nVersion);
351 template<typename Stream>
352 void Unserialize(Stream& s, int nType=0, int nVersion=VERSION)
354 std::vector<unsigned char> vch;
355 ::Unserialize(s, vch, nType, nVersion);
360 bool operator!() const
362 return BN_is_zero(this);
365 CBigNum& operator+=(const CBigNum& b)
367 if (!BN_add(this, this, &b))
368 throw bignum_error("CBigNum::operator+= : BN_add failed");
372 CBigNum& operator-=(const CBigNum& b)
378 CBigNum& operator*=(const CBigNum& b)
381 if (!BN_mul(this, this, &b, pctx))
382 throw bignum_error("CBigNum::operator*= : BN_mul failed");
386 CBigNum& operator/=(const CBigNum& b)
392 CBigNum& operator%=(const CBigNum& b)
398 CBigNum& operator<<=(unsigned int shift)
400 if (!BN_lshift(this, this, shift))
401 throw bignum_error("CBigNum:operator<<= : BN_lshift failed");
405 CBigNum& operator>>=(unsigned int shift)
407 // Note: BN_rshift segfaults on 64-bit if 2^shift is greater than the number
408 // if built on ubuntu 9.04 or 9.10, probably depends on version of openssl
411 if (BN_cmp(&a, this) > 0)
417 if (!BN_rshift(this, this, shift))
418 throw bignum_error("CBigNum:operator>>= : BN_rshift failed");
423 CBigNum& operator++()
426 if (!BN_add(this, this, BN_value_one()))
427 throw bignum_error("CBigNum::operator++ : BN_add failed");
431 const CBigNum operator++(int)
434 const CBigNum ret = *this;
439 CBigNum& operator--()
443 if (!BN_sub(&r, this, BN_value_one()))
444 throw bignum_error("CBigNum::operator-- : BN_sub failed");
449 const CBigNum operator--(int)
452 const CBigNum ret = *this;
458 friend inline const CBigNum operator-(const CBigNum& a, const CBigNum& b);
459 friend inline const CBigNum operator/(const CBigNum& a, const CBigNum& b);
460 friend inline const CBigNum operator%(const CBigNum& a, const CBigNum& b);
465 inline const CBigNum operator+(const CBigNum& a, const CBigNum& b)
468 if (!BN_add(&r, &a, &b))
469 throw bignum_error("CBigNum::operator+ : BN_add failed");
473 inline const CBigNum operator-(const CBigNum& a, const CBigNum& b)
476 if (!BN_sub(&r, &a, &b))
477 throw bignum_error("CBigNum::operator- : BN_sub failed");
481 inline const CBigNum operator-(const CBigNum& a)
484 BN_set_negative(&r, !BN_is_negative(&r));
488 inline const CBigNum operator*(const CBigNum& a, const CBigNum& b)
492 if (!BN_mul(&r, &a, &b, pctx))
493 throw bignum_error("CBigNum::operator* : BN_mul failed");
497 inline const CBigNum operator/(const CBigNum& a, const CBigNum& b)
501 if (!BN_div(&r, NULL, &a, &b, pctx))
502 throw bignum_error("CBigNum::operator/ : BN_div failed");
506 inline const CBigNum operator%(const CBigNum& a, const CBigNum& b)
510 if (!BN_mod(&r, &a, &b, pctx))
511 throw bignum_error("CBigNum::operator% : BN_div failed");
515 inline const CBigNum operator<<(const CBigNum& a, unsigned int shift)
518 if (!BN_lshift(&r, &a, shift))
519 throw bignum_error("CBigNum:operator<< : BN_lshift failed");
523 inline const CBigNum operator>>(const CBigNum& a, unsigned int shift)
530 inline bool operator==(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) == 0); }
531 inline bool operator!=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) != 0); }
532 inline bool operator<=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) <= 0); }
533 inline bool operator>=(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) >= 0); }
534 inline bool operator<(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) < 0); }
535 inline bool operator>(const CBigNum& a, const CBigNum& b) { return (BN_cmp(&a, &b) > 0); }