Blob ConvertFromBase58ShaSquare(RCString s) {
BigInteger bi = 0;
for (const char *p=s; *p; ++p) {
if (const char *q = strchr(s_pszBase58, *p)) {
bi = bi*58 + BigInteger(q-s_pszBase58);
} else
Throw(E_INVALIDARG);
}
vector<byte> v((bi.Length+7)/8);
bi.ToBytes(&v[0], v.size());
if (v.size()>=2 && v.end()[-1]==0 && v.end()[-1]>=0x80)
v.resize(v.size()-1);
vector<byte> r;
for (const char *p=s; *p==s_pszBase58[0]; ++p)
r.push_back(0);
r.resize(r.size()+v.size());
std::reverse_copy(v.begin(), v.end(), r.end()-v.size());
if (r.size() < 4)
Throw(E_FAIL);
SHA256 sha;
HashValue hash = HashValue(sha.ComputeHash(sha.ComputeHash(ConstBuf(&r[0], r.size()-4))));
if (memcmp(hash.data(), &r.end()[-4], 4))
Throw(HRESULT_FROM_WIN32(ERROR_CRC));
return Blob(&r[0], r.size()-4);
}
Blob ConvertFromBase58(RCString s, bool bCheckHash) {
BigInteger bi = 0;
for (const char *p=s; *p; ++p) {
if (const char *q = strchr(s_pszBase58, *p)) {
bi = bi*58 + BigInteger(q-s_pszBase58);
} else
Throw(errc::invalid_argument);
}
vector<byte> v((bi.Length+7)/8);
bi.ToBytes(&v[0], v.size());
if (v.size()>=2 && v.end()[-1]==0 && v.end()[-1]>=0x80)
v.resize(v.size()-1);
vector<byte> r;
for (const char *p=s; *p==s_pszBase58[0]; ++p)
r.push_back(0);
r.resize(r.size()+v.size());
std::reverse_copy(v.begin(), v.end(), r.end()-v.size());
if (r.size() < 4)
Throw(E_FAIL);
if (bCheckHash) {
HashValue hash = HasherEng::GetCurrent()->HashForAddress(ConstBuf(&r[0], r.size()-4));
if (memcmp(hash.data(), &r.end()[-4], 4))
Throw(HRESULT_FROM_WIN32(ERROR_CRC));
}
return Blob(&r[0], r.size()-4);
}
OpensslBn::OpensslBn(const BigInteger& bn) {
int n = (bn.Length+8)/8;
byte *p = (byte*)alloca(n);
bn.ToBytes(p, n);
std::reverse(p, p+n);
SslCheck(m_bn = ::BN_bin2bn(p, n, 0));
}
