git / moonbite-core / src/base58.cpp · raw

// Copyright (c) 2014-2019 The Bitcoin Core developers// Distributed under the MIT software license, see the accompanying// file COPYING or http://www.opensource.org/licenses/mit-license.php.#include <base58.h>#include <hash.h>#include <uint256.h>#include <util/strencodings.h>#include <util/string.h>#include <assert.h>#include <string.h>#include <limits>/** All alphanumeric characters except for "0", "I", "O", and "l" */static const char* pszBase58 = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";static const int8_t mapBase58[256] = {    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1, 0, 1, 2, 3, 4, 5, 6,  7, 8,-1,-1,-1,-1,-1,-1,    -1, 9,10,11,12,13,14,15, 16,-1,17,18,19,20,21,-1,    22,23,24,25,26,27,28,29, 30,31,32,-1,-1,-1,-1,-1,    -1,33,34,35,36,37,38,39, 40,41,42,43,-1,44,45,46,    47,48,49,50,51,52,53,54, 55,56,57,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,    -1,-1,-1,-1,-1,-1,-1,-1, -1,-1,-1,-1,-1,-1,-1,-1,};NODISCARD static bool DecodeBase58(const char* psz, std::vector<unsigned char>& vch, int max_ret_len){    // Skip leading spaces.    while (*psz && IsSpace(*psz))        psz++;    // Skip and count leading '1's.    int zeroes = 0;    int length = 0;    while (*psz == '1') {        zeroes++;        if (zeroes > max_ret_len) return false;        psz++;    }    // Allocate enough space in big-endian base256 representation.    int size = strlen(psz) * 733 /1000 + 1; // log(58) / log(256), rounded up.    std::vector<unsigned char> b256(size);    // Process the characters.    static_assert(sizeof(mapBase58)/sizeof(mapBase58[0]) == 256, "mapBase58.size() should be 256"); // guarantee not out of range    while (*psz && !IsSpace(*psz)) {        // Decode base58 character        int carry = mapBase58[(uint8_t)*psz];        if (carry == -1)  // Invalid b58 character            return false;        int i = 0;        for (std::vector<unsigned char>::reverse_iterator it = b256.rbegin(); (carry != 0 || i < length) && (it != b256.rend()); ++it, ++i) {            carry += 58 * (*it);            *it = carry % 256;            carry /= 256;        }        assert(carry == 0);        length = i;        if (length + zeroes > max_ret_len) return false;        psz++;    }    // Skip trailing spaces.    while (IsSpace(*psz))        psz++;    if (*psz != 0)        return false;    // Skip leading zeroes in b256.    std::vector<unsigned char>::iterator it = b256.begin() + (size - length);    // Copy result into output vector.    vch.reserve(zeroes + (b256.end() - it));    vch.assign(zeroes, 0x00);    while (it != b256.end())        vch.push_back(*(it++));    return true;}std::string EncodeBase58(Span<const unsigned char> input){    // Skip & count leading zeroes.    int zeroes = 0;    int length = 0;    while (input.size() > 0 && input[0] == 0) {        input = input.subspan(1);        zeroes++;    }    // Allocate enough space in big-endian base58 representation.    int size = input.size() * 138 / 100 + 1; // log(256) / log(58), rounded up.    std::vector<unsigned char> b58(size);    // Process the bytes.    while (input.size() > 0) {        int carry = input[0];        int i = 0;        // Apply "b58 = b58 * 256 + ch".        for (std::vector<unsigned char>::reverse_iterator it = b58.rbegin(); (carry != 0 || i < length) && (it != b58.rend()); it++, i++) {            carry += 256 * (*it);            *it = carry % 58;            carry /= 58;        }        assert(carry == 0);        length = i;        input = input.subspan(1);    }    // Skip leading zeroes in base58 result.    std::vector<unsigned char>::iterator it = b58.begin() + (size - length);    while (it != b58.end() && *it == 0)        it++;    // Translate the result into a string.    std::string str;    str.reserve(zeroes + (b58.end() - it));    str.assign(zeroes, '1');    while (it != b58.end())        str += pszBase58[*(it++)];    return str;}bool DecodeBase58(const std::string& str, std::vector<unsigned char>& vchRet, int max_ret_len){    if (!ValidAsCString(str)) {        return false;    }    return DecodeBase58(str.c_str(), vchRet, max_ret_len);}std::string EncodeBase58Check(Span<const unsigned char> input){    // add 4-byte hash check to the end    std::vector<unsigned char> vch(input.begin(), input.end());    uint256 hash = Hash(vch);    vch.insert(vch.end(), (unsigned char*)&hash, (unsigned char*)&hash + 4);    return EncodeBase58(vch);}NODISCARD static bool DecodeBase58Check(const char* psz, std::vector<unsigned char>& vchRet, int max_ret_len){    if (!DecodeBase58(psz, vchRet, max_ret_len > std::numeric_limits<int>::max() - 4 ? std::numeric_limits<int>::max() : max_ret_len + 4) ||        (vchRet.size() < 4)) {        vchRet.clear();        return false;    }    // re-calculate the checksum, ensure it matches the included 4-byte checksum    uint256 hash = Hash(MakeSpan(vchRet).first(vchRet.size() - 4));    if (memcmp(&hash, &vchRet[vchRet.size() - 4], 4) != 0) {        vchRet.clear();        return false;    }    vchRet.resize(vchRet.size() - 4);    return true;}bool DecodeBase58Check(const std::string& str, std::vector<unsigned char>& vchRet, int max_ret){    if (!ValidAsCString(str)) {        return false;    }    return DecodeBase58Check(str.c_str(), vchRet, max_ret);}