path: root/libdevcore/CommonData.cpp

/*
    This file is part of solidity.

    solidity is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    solidity is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with solidity.  If not, see <http://www.gnu.org/licenses/>.
*/
/** @file CommonData.cpp
 * @author Gav Wood <i@gavwood.com>
 * @date 2014
 */

#include <libdevcore/CommonData.h>
#include <libdevcore/Exceptions.h>
#include <libdevcore/SHA3.h>

#include <boost/algorithm/string.hpp>

using namespace std;
using namespace dev;

std::string dev::escaped(std::string const& _s, bool _all)
{
    static const map<char, char> prettyEscapes{{'\r', 'r'}, {'\n', 'n'}, {'\t', 't'}, {'\v', 'v'}};
    std::string ret;
    ret.reserve(_s.size() + 2);
    ret.push_back('"');
    for (auto i: _s)
        if (i == '"' && !_all)
            ret += "\\\"";
        else if (i == '\\' && !_all)
            ret += "\\\\";
        else if (prettyEscapes.count(i) && !_all)
        {
            ret += '\\';
            ret += prettyEscapes.find(i)->second;
        }
        else if (i < ' ' || _all)
        {
            ret += "\\x";
            ret.push_back("0123456789abcdef"[(uint8_t)i / 16]);
            ret.push_back("0123456789abcdef"[(uint8_t)i % 16]);
        }
        else
            ret.push_back(i);
    ret.push_back('"');
    return ret;
}

int dev::fromHex(char _i, WhenError _throw)
{
    if (_i >= '0' && _i <= '9')
        return _i - '0';
    if (_i >= 'a' && _i <= 'f')
        return _i - 'a' + 10;
    if (_i >= 'A' && _i <= 'F')
        return _i - 'A' + 10;
    if (_throw == WhenError::Throw)
        BOOST_THROW_EXCEPTION(BadHexCharacter() << errinfo_invalidSymbol(_i));
    else
        return -1;
}

bytes dev::fromHex(std::string const& _s, WhenError _throw)
{
    unsigned s = (_s.size() >= 2 && _s[0] == '0' && _s[1] == 'x') ? 2 : 0;
    std::vector<uint8_t> ret;
    ret.reserve((_s.size() - s + 1) / 2);

    if (_s.size() % 2)
    {
        int h = fromHex(_s[s++], WhenError::DontThrow);
        if (h != -1)
            ret.push_back(h);
        else if (_throw == WhenError::Throw)
            BOOST_THROW_EXCEPTION(BadHexCharacter());
        else
            return bytes();
    }
    for (unsigned i = s; i < _s.size(); i += 2)
    {
        int h = fromHex(_s[i], WhenError::DontThrow);
        int l = fromHex(_s[i + 1], WhenError::DontThrow);
        if (h != -1 && l != -1)
            ret.push_back((byte)(h * 16 + l));
        else if (_throw == WhenError::Throw)
            BOOST_THROW_EXCEPTION(BadHexCharacter());
        else
            return bytes();
    }
    return ret;
}


bool dev::passesAddressChecksum(string const& _str, bool _strict)
{
    string s = _str.substr(0, 2) == "0x" ? _str.substr(2) : _str;

    if (s.length() != 40)
        return false;

    if (!_strict && (
        _str.find_first_of("abcdef") == string::npos ||
        _str.find_first_of("ABCDEF") == string::npos
    ))
        return true;

    h256 hash = keccak256(boost::algorithm::to_lower_copy(s, std::locale::classic()));
    for (size_t i = 0; i < 40; ++i)
    {
        char addressCharacter = s[i];
        bool lowerCase;
        if ('a' <= addressCharacter && addressCharacter <= 'f')
            lowerCase = true;
        else if ('A' <= addressCharacter && addressCharacter <= 'F')
            lowerCase = false;
        else
            continue;
        unsigned nibble = (unsigned(hash[i / 2]) >> (4 * (1 - (i % 2)))) & 0xf;
        if ((nibble >= 8) == lowerCase)
            return false;
    }
    return true;
}