public static bool CheckFileIntegrity (string filename)
{
if (filename == null)
return false;
byte [] hash = null;
RSA rsa = CryptoConvert.FromCapiKeyBlob (codec_public_key_blob);
byte [] signature = new byte [128];
using (FileStream fs = File.OpenRead (filename)) {
if (!IsSigned (fs))
return false;
hash = HashStream (fs, (int) fs.Length - 132);
fs.Seek (-128, SeekOrigin.End);
if (fs.Read (signature, 0, 128) != 128)
return false;
}
RSAPKCS1SignatureDeformatter def = new RSAPKCS1SignatureDeformatter (rsa);
def.SetHashAlgorithm ("SHA1");
return def.VerifySignature (hash, signature);
}
#endif
