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-rw-r--r--src/test/bignum.h179
1 files changed, 179 insertions, 0 deletions
diff --git a/src/test/bignum.h b/src/test/bignum.h
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+++ b/src/test/bignum.h
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+// 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 <algorithm>
+#include <limits>
+#include <stdexcept>
+#include <stdint.h>
+#include <vector>
+
+#include <openssl/bn.h>
+
+class bignum_error : public std::runtime_error
+{
+public:
+ explicit bignum_error(const std::string& str) : std::runtime_error(str) {}
+};
+
+
+/** 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(long long n) { BN_init(this); setint64(n); }
+
+ explicit CBigNum(const std::vector<unsigned char>& vch)
+ {
+ BN_init(this);
+ setvch(vch);
+ }
+
+ 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 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;
+ }
+
+ 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 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