Volker Steiß <[EMAIL PROTECTED]> writes: > Hello everybody, > > I am on a project using public-private-key methods and just tried using > GnuTLS for this. > I am stuck at this point and hope someone can help me out: > First I created a public private key (it's long ago, so I cant tell you how I > did it exactly). > I have created a signature with gnutls_x509_privkey_sign_data(PRIV_KEY), > converted it to readable text with gnutls_hex_encode() and stored the result > (Data + Signature) into a file. > Now I want to verify the created data: I read the data and the signature, > decode the signature with gnutls_hex_decode() and try to verify it with > gnutls_x509_privkey_verify_data(PUB_KEY). But here I get return code 0, which > means no success. > > Verification overview: >>>>> - somecode > init_gnutls () > ... > gnutls_hex_decode (&temp, signature.data, &signature.size) > ... > gnutls_x509_privkey_init (&key) > gnutls_x509_privkey_import (key, &key_datum, GNUTLS_X509_FMT_PEM) > result = gnutls_x509_privkey_verify_data (key, flags, &uid, &signature) > //result = 0 > ... > <<<< - end of somecode > > > Btw: What I realize at "gnutls_hex_decode (&temp, signature.data, > &signature.size)" is that temp.size is 512 bytes and signature.size also is > 512. Am I wrong when I say: It should be smaller after decoding?
Did you check errors from all functions? Hex decoding a 512 byte string should not give another 512 byte string. Did you allocate a signature.data buffer before calling gnutls_hex_decode? Btw, if you aren't sure that you must use these functions, you probably want to use a higher-layer message signature format instead of low-level sign/verify primitives. Standard formats for this is OpenPGP (try GnuPG) and CMS/SMIME (try gpgsm). /Simon _______________________________________________ Help-gnutls mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gnutls
