/*
* Returns only 0 or 1. If 1 it means that the CRL
* was successfuly verified.
*
* 'flags': an OR of the gnutls_certificate_verify_flags enumeration.
*
* Output will hold information about the verification
* procedure.
*/
static int
_gnutls_verify_crl2 (gnutls_x509_crl_t crl,
const gnutls_x509_crt_t * trusted_cas,
int tcas_size, unsigned int flags, unsigned int *output)
{
/* CRL is ignored for now */
gnutls_datum_t crl_signed_data = { NULL, 0 };
gnutls_datum_t crl_signature = { NULL, 0 };
gnutls_x509_crt_t issuer;
int result, hash_algo;
if (output)
*output = 0;
if (tcas_size >= 1)
issuer = find_crl_issuer (crl, trusted_cas, tcas_size);
else
{
gnutls_assert ();
if (output)
*output |= GNUTLS_CERT_SIGNER_NOT_FOUND | GNUTLS_CERT_INVALID;
return 0;
}
/* issuer is not in trusted certificate
* authorities.
*/
if (issuer == NULL)
{
gnutls_assert ();
if (output)
*output |= GNUTLS_CERT_SIGNER_NOT_FOUND | GNUTLS_CERT_INVALID;
return 0;
}
if (!(flags & GNUTLS_VERIFY_DISABLE_CA_SIGN))
{
if (gnutls_x509_crt_get_ca_status (issuer, NULL) != 1)
{
gnutls_assert ();
if (output)
*output |= GNUTLS_CERT_SIGNER_NOT_CA | GNUTLS_CERT_INVALID;
return 0;
}
}
result =
_gnutls_x509_get_signed_data (crl->crl, "tbsCertList", &crl_signed_data);
if (result < 0)
{
gnutls_assert ();
goto cleanup;
}
result = _gnutls_x509_get_signature (crl->crl, "signature", &crl_signature);
if (result < 0)
{
gnutls_assert ();
goto cleanup;
}
result = _gnutls_x509_get_signature_algorithm(crl->crl, "signatureAlgorithm.algorithm");
if (result < 0)
{
gnutls_assert ();
goto cleanup;
}
hash_algo = gnutls_sign_get_hash_algorithm(result);
result =
_gnutls_x509_verify_data (hash_algo, &crl_signed_data, &crl_signature,
issuer);
if (result == GNUTLS_E_PK_SIG_VERIFY_FAILED)
{
gnutls_assert ();
/* error. ignore it */
if (output)
*output |= GNUTLS_CERT_INVALID | GNUTLS_CERT_SIGNATURE_FAILURE;
result = 0;
}
else if (result < 0)
{
gnutls_assert ();
goto cleanup;
}
{
int sigalg;
sigalg = gnutls_x509_crl_get_signature_algorithm (crl);
if (((sigalg == GNUTLS_SIGN_RSA_MD2) &&
!(flags & GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD2)) ||
((sigalg == GNUTLS_SIGN_RSA_MD5) &&
!(flags & GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5)))
{
if (output)
*output |= GNUTLS_CERT_INSECURE_ALGORITHM | GNUTLS_CERT_INVALID;
result = 0;
}
}
cleanup:
_gnutls_free_datum (&crl_signed_data);
_gnutls_free_datum (&crl_signature);
return result;
}
/**
* gnutls_x509_crl_verify:
* @crl: is the crl to be verified
* @trusted_cas: is a certificate list that is considered to be trusted one
* @tcas_size: holds the number of CA certificates in CA_list
* @flags: Flags that may be used to change the verification algorithm. Use OR of the gnutls_certificate_verify_flags enumerations.
* @verify: will hold the crl verification output.
*
* This function will try to verify the given crl and return its verification status.
* See gnutls_x509_crt_list_verify() for a detailed description of
* return values. Note that since GnuTLS 3.1.4 this function includes
* the time checks.
*
* Note that value in @verify is set only when the return value of this
* function is success (i.e, failure to trust a CRL a certificate does not imply
* a negative return value).
*
* Before GnuTLS 3.5.7 this function would return zero or a positive
* number on success.
*
* Returns: On success, %GNUTLS_E_SUCCESS (0), otherwise a
* negative error value.
**/
int
gnutls_x509_crl_verify(gnutls_x509_crl_t crl,
const gnutls_x509_crt_t * trusted_cas,
unsigned tcas_size, unsigned int flags,
unsigned int *verify)
{
/* CRL is ignored for now */
gnutls_datum_t crl_signed_data = { NULL, 0 };
gnutls_datum_t crl_signature = { NULL, 0 };
gnutls_x509_crt_t issuer = NULL;
int result, hash_algo;
time_t now = gnutls_time(0);
unsigned int usage;
if (verify)
*verify = 0;
if (tcas_size >= 1)
issuer = find_crl_issuer(crl, trusted_cas, tcas_size);
result =
_gnutls_x509_get_signed_data(crl->crl, &crl->der, "tbsCertList",
&crl_signed_data);
if (result < 0) {
gnutls_assert();
if (verify)
*verify |= GNUTLS_CERT_INVALID;
goto cleanup;
}
result =
_gnutls_x509_get_signature(crl->crl, "signature",
&crl_signature);
if (result < 0) {
gnutls_assert();
if (verify)
*verify |= GNUTLS_CERT_INVALID;
goto cleanup;
}
result =
_gnutls_x509_get_signature_algorithm(crl->crl,
"signatureAlgorithm.algorithm");
if (result < 0) {
gnutls_assert();
if (verify)
*verify |= GNUTLS_CERT_INVALID;
goto cleanup;
}
hash_algo = gnutls_sign_get_hash_algorithm(result);
/* issuer is not in trusted certificate
* authorities.
*/
if (issuer == NULL) {
gnutls_assert();
if (verify)
*verify |=
GNUTLS_CERT_SIGNER_NOT_FOUND |
GNUTLS_CERT_INVALID;
} else {
if (!(flags & GNUTLS_VERIFY_DISABLE_CA_SIGN)) {
if (gnutls_x509_crt_get_ca_status(issuer, NULL) != 1) {
gnutls_assert();
if (verify)
*verify |=
GNUTLS_CERT_SIGNER_NOT_CA |
GNUTLS_CERT_INVALID;
}
result =
gnutls_x509_crt_get_key_usage(issuer, &usage, NULL);
if (result != GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
if (result < 0) {
gnutls_assert();
if (verify)
*verify |= GNUTLS_CERT_INVALID;
} else if (!(usage & GNUTLS_KEY_CRL_SIGN)) {
gnutls_assert();
if (verify)
*verify |=
GNUTLS_CERT_SIGNER_CONSTRAINTS_FAILURE
| GNUTLS_CERT_INVALID;
}
}
}
result =
_gnutls_x509_verify_data(mac_to_entry(hash_algo),
&crl_signed_data, &crl_signature,
issuer);
if (result == GNUTLS_E_PK_SIG_VERIFY_FAILED) {
gnutls_assert();
/* error. ignore it */
if (verify)
*verify |= GNUTLS_CERT_SIGNATURE_FAILURE;
result = 0;
} else if (result < 0) {
gnutls_assert();
if (verify)
*verify |= GNUTLS_CERT_INVALID;
goto cleanup;
} else if (result >= 0) {
result = 0; /* everything ok */
}
}
{
int sigalg;
sigalg = gnutls_x509_crl_get_signature_algorithm(crl);
if (((sigalg == GNUTLS_SIGN_RSA_MD2) &&
!(flags & GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD2)) ||
((sigalg == GNUTLS_SIGN_RSA_MD5) &&
!(flags & GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5))) {
if (verify)
*verify |= GNUTLS_CERT_INSECURE_ALGORITHM;
result = 0;
}
}
if (gnutls_x509_crl_get_this_update(crl) > now && verify)
*verify |= GNUTLS_CERT_REVOCATION_DATA_ISSUED_IN_FUTURE;
if (gnutls_x509_crl_get_next_update(crl) < now && verify)
*verify |= GNUTLS_CERT_REVOCATION_DATA_SUPERSEDED;
cleanup:
if (verify && *verify != 0)
*verify |= GNUTLS_CERT_INVALID;
_gnutls_free_datum(&crl_signed_data);
_gnutls_free_datum(&crl_signature);
return result;
}
