+
+static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)
+{
+ char curve_name[80];
+ size_t curve_name_len;
+ int curve_nid;
+
+ if (pkey == NULL || !EVP_PKEY_is_a(pkey, "EC"))
+ return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;
+
+ if (!EVP_PKEY_get_group_name(pkey, curve_name, sizeof(curve_name),
+ &curve_name_len))
+ return X509_V_ERR_SUITE_B_INVALID_CURVE;
+
+ curve_nid = OBJ_txt2nid(curve_name);
+ /* Check curve is consistent with LOS */
+ if (curve_nid == NID_secp384r1) { /* P-384 */
+ /*
+ * Check signature algorithm is consistent with curve.
+ */
+ if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)
+ return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
+ if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))
+ return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
+ /* If we encounter P-384 we cannot use P-256 later */
+ *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;
+ } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */
+ if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)
+ return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
+ if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))
+ return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
+ } else {
+ return X509_V_ERR_SUITE_B_INVALID_CURVE;
+ }
+ return X509_V_OK;
+}
+
+int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
+ unsigned long flags)
+{
+ int rv, i, sign_nid;
+ EVP_PKEY *pk;
+ unsigned long tflags = flags;
+
+ if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
+ return X509_V_OK;
+
+ /* If no EE certificate passed in must be first in chain */
+ if (x == NULL) {
+ x = sk_X509_value(chain, 0);
+ i = 1;
+ } else {
+ i = 0;
+ }
+ pk = X509_get0_pubkey(x);
+
+ /*
+ * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build
+ * a chain all, just report trust success or failure, but must also report
+ * Suite-B errors if applicable. This is indicated via a NULL chain
+ * pointer. All we need to do is check the leaf key algorithm.
+ */
+ if (chain == NULL)
+ return check_suite_b(pk, -1, &tflags);
+
+ if (X509_get_version(x) != 2) {
+ rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
+ /* Correct error depth */
+ i = 0;
+ goto end;
+ }
+
+ /* Check EE key only */
+ rv = check_suite_b(pk, -1, &tflags);
+ if (rv != X509_V_OK) {
+ /* Correct error depth */
+ i = 0;
+ goto end;
+ }
+ for (; i < sk_X509_num(chain); i++) {
+ sign_nid = X509_get_signature_nid(x);
+ x = sk_X509_value(chain, i);
+ if (X509_get_version(x) != 2) {
+ rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
+ goto end;
+ }
+ pk = X509_get0_pubkey(x);
+ rv = check_suite_b(pk, sign_nid, &tflags);
+ if (rv != X509_V_OK)
+ goto end;
+ }
+
+ /* Final check: root CA signature */
+ rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);
+ end:
+ if (rv != X509_V_OK) {
+ /* Invalid signature or LOS errors are for previous cert */
+ if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM
+ || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)
+ i--;
+ /*
+ * If we have LOS error and flags changed then we are signing P-384
+ * with P-256. Use more meaningful error.
+ */
+ if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)
+ rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;
+ if (perror_depth)
+ *perror_depth = i;
+ }
+ return rv;
+}
+
+int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
+{
+ int sign_nid;
+ if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
+ return X509_V_OK;
+ sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);
+ return check_suite_b(pk, sign_nid, &flags);
+}
+
+#else
+int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
+ unsigned long flags)
+{
+ return 0;
+}
+
+int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
+{
+ return 0;
+}
+