/// <summary>Verify the certificate content according to rules defined
/// at 3.1 in dir-spec.txt</summary>
internal void Verify(Authority certificateOwner)
{
if (null == certificateOwner)
{
throw new ArgumentNullException();
}
// Verify the CrossSignature.
// 1) Get IdentityKey digest.
byte[] identityKeyDigest = SHA1.Hash(IdentityKey);
// 2) Make sure it matches the declared owner.
// was implemented as router_digest_is_trusted_dir(identityKeyDigest);
// TODO : This will fail on an identity key update.
byte[] certificateOwnerIdentityKeyDigest =
SHA1.Hash(certificateOwner.Identity.DecodeHexadecimalEncodedString());
if (!Helpers.AreEquals(identityKeyDigest, certificateOwnerIdentityKeyDigest))
{
throw new TorSecurityException();
}
// 2) Compute digest of ToBeHashed
IntPtr hHasher = IntPtr.Zero;
IntPtr nativeSignature = IntPtr.Zero;
IntPtr hPublicSigningKey = IntPtr.Zero;
try {
SHA1.Hash(ToBeHashed, out hHasher);
Marshal.AllocCoTaskMem(Signature.Length);
Marshal.Copy(Signature, 0, nativeSignature, Signature.Length);
hPublicSigningKey = CryptoProvider.ImportRsaPublicKey(SigningKey);
if (!Advapi32.CryptVerifySignature(hHasher, nativeSignature, Signature.Length,
hPublicSigningKey, IntPtr.Zero, Advapi32.SignatureVerificationFlags.NoHashOID))
{
throw new CryptographyException((WinErrors)(uint)Marshal.GetLastWin32Error());
}
}
finally {
if (IntPtr.Zero != hPublicSigningKey)
{
Advapi32.CryptDestroyKey(hPublicSigningKey);
}
if (IntPtr.Zero != nativeSignature)
{
Marshal.FreeCoTaskMem(nativeSignature);
}
if (IntPtr.Zero != hHasher)
{
Advapi32.CryptDestroyHash(hHasher);
}
}
// Remind : HashValue = SHA1.Hash(base._toBeHashed);
//byte[] signed_digest = crypto_pk_public_checksig(IdentityKey, tok->object_body, tok->object_size)
// crypto_pk_public_checksig main action is :
//RSA_public_decrypt((int)fromlen,
// (unsigned char *)from, (unsigned char*)to,
// env->key, RSA_PKCS1_PADDING);
//byte[] signed_digest = RSA_public_decrypt((int)fromlen,
// (byte[])from, (byte[])to,
// env->key, RSA_PKCS1_PADDING);
//// tor_memneq(identityKeyDigest, signed_digest);
//if (!Helpers.AreEquals(identityKeyDigest, signedDigest)) {
// throw new TorSecurityException();
//}
}