bool DigestVerifierTemplate<P,F>::VerifyDigest(const byte *digest, unsigned int digestLen, const byte *signature) const
{
SecByteBlock paddedBlock(PaddedBlockByteLength());
f.ApplyFunction(Integer(signature, DigestSignatureLength())).Encode(paddedBlock, paddedBlock.size);
SecByteBlock recoveredDigest(MaxDigestLength());
unsigned int recoveredDigestLen = pad.Unpad(paddedBlock, PaddedBlockBitLength(), recoveredDigest);
return digestLen == recoveredDigestLen && memcmp(digest, recoveredDigest, digestLen) == 0;
}
void DigestSignerTemplate<P,F>::SignDigest(RandomNumberGenerator &rng, const byte *digest, unsigned int digestLength, byte *signature) const
{
assert(digestLength <= MaxDigestLength());
SecByteBlock paddedBlock(PaddedBlockByteLength());
pad.Pad(rng, digest, digestLength, paddedBlock, PaddedBlockBitLength());
f.CalculateInverse(Integer(paddedBlock, paddedBlock.size)).Encode(signature, DigestSignatureLength());
}
bool NRDigestVerifier::VerifyDigest(const byte *digest, unsigned int digestLen, const byte *signature) const
{
assert(digestLen <= MaxDigestLength());
Integer h = EncodeDigest(digest, digestLen);
unsigned int qLen = m_q.ByteCount();
Integer r(signature, qLen);
Integer s(signature+qLen, qLen);
return RawVerify(h, r, s);
}
void NRDigestSigner::SignDigest(RandomNumberGenerator &rng, const byte *digest, unsigned int digestLen, byte *signature) const
{
assert(digestLen <= MaxDigestLength());
Integer h = EncodeDigest(digest, digestLen);
Integer r;
Integer s;
RawSign(rng, h, r, s);
unsigned int qLen = m_q.ByteCount();
r.Encode(signature, qLen);
s.Encode(signature+qLen, qLen);
}
