Key length used in SMIME Mails

[Tim Tassonis]

Hi

I've got to find out the keysize used in an S/MIME encrypted mail.

I looked around in the openssl code and tried the following:


X509_ALGOR *alg;
PKCS7 *p7;
int p7_type;
BIO *mail_bio *indata;
...
p7 = SMIME_read_PKCS7(mail_bio, &indata);
p7_type = OBJ_obj2nid(p7->type);
switch (p7_type) {
  case NID_pkcs7_signedAndEnveloped:
    alg=p7->d.signed_and_enveloped->enc_data->algorithm;
    break;
  case NID_pkcs7_enveloped:
    alg=p7->d.enveloped->enc_data->algorithm;
    break;
  default;
    return;
    break;
}
printf("Alg: %s\n",OBJ_nid2sn(OBJ_obj2nid(alg->algorithm)));
printf("Len: %ld\n",ASN1_INTEGER_get(alg->parameter->value.integer));


I then get the algorithm as desired:
Alg: RC2-CBC
or
Alg: DES-EDE3-CBC

but the keysize is always -1:
Key: -1
Key: -1


In pk7_attr.c (lile 110) in PKCS7_simple_smimecap, the line 134
alg->parameter->value.integer = nbit;

implies that the keysize is stored there, as the funcion is called in pk7_smime.c like 
this:
PKCS7_simple_smimecap (smcap, NID_rc2_cbc, 128);

What am I doing wrong.

Bye
Tim


______________________________________________________________________
OpenSSL Project                                 http://www.openssl.org
User Support Mailing List                    [EMAIL PROTECTED]
Automated List Manager                           [EMAIL PROTECTED]