CryptoPP::SecByteBlock
prf (
CryptoPP::SecByteBlock const& secret,
char const* label,
CryptoPP::SecByteBlock const& seed,
size_t length
)
{
size_t half, len;
CryptoPP::SecByteBlock first, second;
CryptoPP::SecByteBlock::iterator it1, it2;
half = secret.size() >> 1;
len = half + (secret.size() & 1);
first.Assign(secret.data(), len);
second.Assign(secret.data()+half, len);
first = prf<H1>(first, label, seed, length);
second = prf<H2>(second, label, seed, length);
it1 = first.begin();
it2 = second.begin();
while (it1 != first.end() && it2 != second.end())
{
(*it1) ^= (*it2);
++it1;
++it2;
}
return first;
}
int main() {
{
CryptoPP::SHA512 sha2;
unsigned char digest[CryptoPP::SHA512::DIGESTSIZE];
sha2.Final(digest);
}
{
std::string data;
const CryptoPP::SecByteBlock key;
const CryptoPP::SecByteBlock iv;
CryptoPP::SecByteBlock ret(0, CryptoPP::AES::MAX_KEYLENGTH);
CryptoPP::StringSource(data, true, new CryptoPP::HashFilter(*(new CryptoPP::SHA3_512), new CryptoPP::ArraySink(ret, CryptoPP::AES::MAX_KEYLENGTH)));
CryptoPP::GCM< CryptoPP::AES, CryptoPP::GCM_64K_Tables >::Encryption pwenc;
pwenc.SetKeyWithIV(key.data(), key.size(), iv.data(), iv.size());
std::string cipher;
CryptoPP::StringSource(data, true, new CryptoPP::AuthenticatedEncryptionFilter(pwenc, new CryptoPP::StringSink(cipher), false, 16));
}
{
const CryptoPP::SecByteBlock key;
const CryptoPP::SecByteBlock iv;
CryptoPP::GCM< CryptoPP::AES, CryptoPP::GCM_64K_Tables >::Decryption pwdec;
pwdec.SetKeyWithIV(key.data(), key.size(), iv.data(), iv.size());
}
{
CryptoPP::SecByteBlock ret(0, CryptoPP::AES::BLOCKSIZE);
std::string str;
CryptoPP::StringSource(str, true, new CryptoPP::Base64Decoder(new CryptoPP::ArraySink(ret, CryptoPP::AES::BLOCKSIZE)));
}
return 0;
}
GenericCryptoOutputFilter(
std::ostream &stream,
const CryptoPP::SecByteBlock &key,
const CryptoPP::SecByteBlock &iv): CryptoOutputFilter(stream){
this->data.reset(new impl);
this->data->e.SetKeyWithIV(key, key.size(), iv.data(), iv.size());
this->data->filter.reset(new CryptoPP::StreamTransformationFilter(this->data->e));
}
CryptoPP::SecByteBlock
prf (
CryptoPP::SecByteBlock const& secret,
char const* label,
CryptoPP::SecByteBlock const& seed,
size_t length
)
{
CryptoPP::HMAC<H> hmac(secret.data(), secret.size());
CryptoPP::SecByteBlock hash_seed, A, cur_seed, output;
// PRF(secret, label, seed) = P_hash(secret, label + seed)
// P_hash(secret, seed) = HMAC_hash(secret, A(1) + seed) +
// HMAC_hash(secret, A(2) + seed) +
// HMAC_hash(secret, A(3) + seed) + ...
// A(0) = seed
// A(i) = HMAC_hash(secret, A(i-1))
// Make the seed for P_<hash>.
hash_seed.Assign(
reinterpret_cast<byte const*>(label),
strlen(label)
);
hash_seed += seed;
// Calculate A(1) = HMAC_hash(secret, A(0)=seed)
A.CleanNew(hmac.DigestSize());
hmac.CalculateDigest(A.data(), hash_seed.data(), hash_seed.size());
// Calculate P_hash(secret, seed)
while (output.size() < length)
{
cur_seed = A + hash_seed;
hmac.Update(cur_seed.data(), cur_seed.size());
cur_seed.resize(hmac.DigestSize());
hmac.Final(cur_seed.data());
output += cur_seed;
hmac.Update(A.data(), A.size());
hmac.Final(A.data());
}
// Trim and return.
output.resize(length);
return output;
}
// Compute
bool diffie_hellman::compute(const CryptoPP::SecByteBlock& input, const bool validate /*= true*/)
{
assert(!input.empty());
return m_dh.Agree(m_shared, m_private, reinterpret_cast<const byte*>(input.data()), validate);
}
