pr_devel("==>%s()\n", __func__);
- if (cert->unsupported_crypto)
- return -ENOPKG;
- if (sig->s)
+ if (!cert->pub->pkey_algo)
+ cert->unsupported_key = true;
+
+ if (!sig->pkey_algo)
+ cert->unsupported_sig = true;
+
+ /* We check the hash if we can - even if we can't then verify it */
+ if (!sig->hash_algo) {
+ cert->unsupported_sig = true;
return 0;
+ }
sig->s = kmemdup(cert->raw_sig, cert->raw_sig_size, GFP_KERNEL);
if (!sig->s)
tfm = crypto_alloc_shash(sig->hash_algo, 0, 0);
if (IS_ERR(tfm)) {
if (PTR_ERR(tfm) == -ENOENT) {
- cert->unsupported_crypto = true;
- return -ENOPKG;
+ cert->unsupported_sig = true;
+ return 0;
}
return PTR_ERR(tfm);
}
pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
}
-EXPORT_SYMBOL_GPL(x509_get_sig_params);
/*
- * Check the signature on a certificate using the provided public key
+ * Check for self-signedness in an X.509 cert and if found, check the signature
+ * immediately if we can.
*/
-int x509_check_signature(const struct public_key *pub,
- struct x509_certificate *cert)
+int x509_check_for_self_signed(struct x509_certificate *cert)
{
- int ret;
+ int ret = 0;
pr_devel("==>%s()\n", __func__);
- ret = x509_get_sig_params(cert);
- if (ret < 0)
- return ret;
+ if (cert->sig->auth_ids[0] || cert->sig->auth_ids[1]) {
+ /* If the AKID is present it may have one or two parts. If
+ * both are supplied, both must match.
+ */
+ bool a = asymmetric_key_id_same(cert->skid, cert->sig->auth_ids[1]);
+ bool b = asymmetric_key_id_same(cert->id, cert->sig->auth_ids[0]);
+
+ if (!a && !b)
+ goto not_self_signed;
+
+ ret = -EKEYREJECTED;
+ if (((a && !b) || (b && !a)) &&
+ cert->sig->auth_ids[0] && cert->sig->auth_ids[1])
+ goto out;
+ }
+
+ ret = public_key_verify_signature(cert->pub, cert->sig);
+ if (ret < 0) {
+ if (ret == -ENOPKG) {
+ cert->unsupported_sig = true;
+ ret = 0;
+ }
+ goto out;
+ }
+
+ pr_devel("Cert Self-signature verified");
+ cert->self_signed = true;
- ret = public_key_verify_signature(pub, cert->sig);
- if (ret == -ENOPKG)
- cert->unsupported_crypto = true;
- pr_debug("Cert Verification: %d\n", ret);
+out:
+ pr_devel("<==%s() = %d\n", __func__, ret);
return ret;
+
+not_self_signed:
+ pr_devel("<==%s() = 0 [not]\n", __func__);
+ return 0;
}
-EXPORT_SYMBOL_GPL(x509_check_signature);
/*
* Check the new certificate against the ones in the trust keyring. If one of
struct key *key;
int ret = 1;
+ if (!sig->auth_ids[0] && !sig->auth_ids[1])
+ return 1;
+
if (!trust_keyring)
return -EOPNOTSUPP;
-
if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid))
return -EPERM;
+ if (cert->unsupported_sig)
+ return -ENOPKG;
key = x509_request_asymmetric_key(trust_keyring,
sig->auth_ids[0], sig->auth_ids[1],
false);
- if (!IS_ERR(key)) {
- if (!use_builtin_keys
- || test_bit(KEY_FLAG_BUILTIN, &key->flags))
- ret = x509_check_signature(key->payload.data[asym_crypto],
- cert);
- key_put(key);
+ if (IS_ERR(key))
+ return PTR_ERR(key);
+
+ if (!use_builtin_keys ||
+ test_bit(KEY_FLAG_BUILTIN, &key->flags)) {
+ ret = public_key_verify_signature(
+ key->payload.data[asym_crypto], cert->sig);
+ if (ret == -ENOPKG)
+ cert->unsupported_sig = true;
}
+ key_put(key);
return ret;
}
pr_devel("Cert Issuer: %s\n", cert->issuer);
pr_devel("Cert Subject: %s\n", cert->subject);
- if (!cert->pub->pkey_algo ||
- !cert->sig->pkey_algo ||
- !cert->sig->hash_algo) {
+ if (cert->unsupported_key) {
ret = -ENOPKG;
goto error_free_cert;
}
pr_devel("Cert Key Algo: %s\n", cert->pub->pkey_algo);
pr_devel("Cert Valid period: %lld-%lld\n", cert->valid_from, cert->valid_to);
- pr_devel("Cert Signature: %s + %s\n",
- cert->sig->pkey_algo,
- cert->sig->hash_algo);
cert->pub->id_type = "X509";
- /* Check the signature on the key if it appears to be self-signed */
- if ((!cert->sig->auth_ids[0] && !cert->sig->auth_ids[1]) ||
- asymmetric_key_id_same(cert->skid, cert->sig->auth_ids[1]) ||
- asymmetric_key_id_same(cert->id, cert->sig->auth_ids[0])) {
- ret = x509_check_signature(cert->pub, cert); /* self-signed */
- if (ret < 0)
- goto error_free_cert;
- } else if (!prep->trusted) {
+ /* See if we can derive the trustability of this certificate.
+ *
+ * When it comes to self-signed certificates, we cannot evaluate
+ * trustedness except by the fact that we obtained it from a trusted
+ * location. So we just rely on x509_validate_trust() failing in this
+ * case.
+ *
+ * Note that there's a possibility of a self-signed cert matching a
+ * cert that we have (most likely a duplicate that we already trust) -
+ * in which case it will be marked trusted.
+ */
+ if (cert->unsupported_sig || cert->self_signed) {
+ public_key_signature_free(cert->sig);
+ cert->sig = NULL;
+ } else {
+ pr_devel("Cert Signature: %s + %s\n",
+ cert->sig->pkey_algo, cert->sig->hash_algo);
+
ret = x509_validate_trust(cert, get_system_trusted_keyring());
if (ret)
ret = x509_validate_trust(cert, get_ima_mok_keyring());
+ if (ret == -EKEYREJECTED)
+ goto error_free_cert;
if (!ret)
- prep->trusted = 1;
+ prep->trusted = true;
}
/* Propose a description */
projects / cascardo / linux.git / blobdiff