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Diffstat (limited to 'lib/include/base58.h')
| -rw-r--r-- | lib/include/base58.h | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/lib/include/base58.h b/lib/include/base58.h new file mode 100644 index 0000000000..7acdf63ae3 --- /dev/null +++ b/lib/include/base58.h @@ -0,0 +1,208 @@ +// Copyright (c) 2009-2010 Satoshi Nakamoto +// Distributed under the MIT/X11 software license, see the accompanying +// file license.txt or http://www.opensource.org/licenses/mit-license.php. + + +// +// Why base-58 instead of standard base-64 encoding? +// - Don't want 0OIl characters that look the same in some fonts and +// could be used to create visually identical looking account numbers. +// - A std::string with non-alphanumeric characters is not as easily accepted as an account number. +// - E-mail usually won't line-break if there's no punctuation to break at. +// - Doubleclicking selects the whole number as one word if it's all alphanumeric. +// +#ifndef BITCOIN_BASE58_H +#define BITCOIN_BASE58_H + +#include <string> +#include <vector> +#include "bignum.h" + +static const char* pszBase58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"; + + +inline std::string EncodeBase58(const unsigned char* pbegin, const unsigned char* pend) +{ + CAutoBN_CTX pctx; + CBigNum bn58 = 58; + CBigNum bn0 = 0; + + // Convert big endian data to little endian + // Extra zero at the end make sure bignum will interpret as a positive number + std::vector<unsigned char> vchTmp(pend-pbegin+1, 0); + reverse_copy(pbegin, pend, vchTmp.begin()); + + // Convert little endian data to bignum + CBigNum bn; + bn.setvch(vchTmp); + + // Convert bignum to std::string + std::string str; + str.reserve((pend - pbegin) * 138 / 100 + 1); + CBigNum dv; + CBigNum rem; + while (bn > bn0) + { + if (!BN_div(&dv, &rem, &bn, &bn58, pctx)) + throw bignum_error("EncodeBase58 : BN_div failed"); + bn = dv; + unsigned int c = rem.getulong(); + str += pszBase58[c]; + } + + // Leading zeroes encoded as base58 zeros + for (const unsigned char* p = pbegin; p < pend && *p == 0; p++) + str += pszBase58[0]; + + // Convert little endian std::string to big endian + reverse(str.begin(), str.end()); + return str; +} + +inline std::string EncodeBase58(const std::vector<unsigned char>& vch) +{ + return EncodeBase58(&vch[0], &vch[0] + vch.size()); +} + +inline bool DecodeBase58(const char* psz, std::vector<unsigned char>& vchRet) +{ + CAutoBN_CTX pctx; + vchRet.clear(); + CBigNum bn58 = 58; + CBigNum bn = 0; + CBigNum bnChar; + while (isspace(*psz)) + psz++; + + // Convert big endian std::string to bignum + for (const char* p = psz; *p; p++) + { + const char* p1 = strchr(pszBase58, *p); + if (p1 == NULL) + { + while (isspace(*p)) + p++; + if (*p != '\0') + return false; + break; + } + bnChar.setulong(p1 - pszBase58); + if (!BN_mul(&bn, &bn, &bn58, pctx)) + throw bignum_error("DecodeBase58 : BN_mul failed"); + bn += bnChar; + } + + // Get bignum as little endian data + std::vector<unsigned char> vchTmp = bn.getvch(); + + // Trim off sign byte if present + if (vchTmp.size() >= 2 && vchTmp.end()[-1] == 0 && vchTmp.end()[-2] >= 0x80) + vchTmp.erase(vchTmp.end()-1); + + // Restore leading zeros + int nLeadingZeros = 0; + for (const char* p = psz; *p == pszBase58[0]; p++) + nLeadingZeros++; + vchRet.assign(nLeadingZeros + vchTmp.size(), 0); + + // Convert little endian data to big endian + reverse_copy(vchTmp.begin(), vchTmp.end(), vchRet.end() - vchTmp.size()); + return true; +} + +inline bool DecodeBase58(const std::string& str, std::vector<unsigned char>& vchRet) +{ + return DecodeBase58(str.c_str(), vchRet); +} + + + + + +inline std::string EncodeBase58Check(const std::vector<unsigned char>& vchIn) +{ + // add 4-byte hash check to the end + std::vector<unsigned char> vch(vchIn); + uint256 hash = Hash(vch.begin(), vch.end()); + vch.insert(vch.end(), (unsigned char*)&hash, (unsigned char*)&hash + 4); + return EncodeBase58(vch); +} + +inline bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRet) +{ + if (!DecodeBase58(psz, vchRet)) + return false; + if (vchRet.size() < 4) + { + vchRet.clear(); + return false; + } + uint256 hash = Hash(vchRet.begin(), vchRet.end()-4); + if (memcmp(&hash, &vchRet.end()[-4], 4) != 0) + { + vchRet.clear(); + return false; + } + vchRet.resize(vchRet.size()-4); + return true; +} + +inline bool DecodeBase58Check(const std::string& str, std::vector<unsigned char>& vchRet) +{ + return DecodeBase58Check(str.c_str(), vchRet); +} + + + + + + +#define ADDRESSVERSION ((unsigned char)(fTestNet ? 111 : 0)) + +inline std::string Hash160ToAddress(uint160 hash160) +{ + // add 1-byte version number to the front + std::vector<unsigned char> vch(1, ADDRESSVERSION); + vch.insert(vch.end(), UBEGIN(hash160), UEND(hash160)); + return EncodeBase58Check(vch); +} + +inline bool AddressToHash160(const char* psz, uint160& hash160Ret) +{ + std::vector<unsigned char> vch; + if (!DecodeBase58Check(psz, vch)) + return false; + if (vch.empty()) + return false; + unsigned char nVersion = vch[0]; + if (vch.size() != sizeof(hash160Ret) + 1) + return false; + memcpy(&hash160Ret, &vch[1], sizeof(hash160Ret)); + return (nVersion <= ADDRESSVERSION); +} + +inline bool AddressToHash160(const std::string& str, uint160& hash160Ret) +{ + return AddressToHash160(str.c_str(), hash160Ret); +} + +inline bool IsValidBitcoinAddress(const char* psz) +{ + uint160 hash160; + return AddressToHash160(psz, hash160); +} + +inline bool IsValidBitcoinAddress(const std::string& str) +{ + return IsValidBitcoinAddress(str.c_str()); +} + + + + +inline std::string PubKeyToAddress(const std::vector<unsigned char>& vchPubKey) +{ + return Hash160ToAddress(Hash160(vchPubKey)); +} + +#endif |