Don't include any TLSv1.3 ciphersuites that are disabled

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Ben Kaduk <kaduk@mit.edu>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/16925)

diff --git a/ssl/ssl_ciph.c b/ssl/ssl_ciph.c
index e38e1c27e6cf16b04d468f8349d89a3ab7a67e21..046e4aac06f54bdac2e3e3281a18004b21b9b871 100644 (file)
--- a/ssl/ssl_ciph.c
+++ b/ssl/ssl_ciph.c
@@ -1370,7 +1370,8 @@ static int update_cipher_list_by_id(STACK_OF(SSL_CIPHER) **cipher_list_by_id,
     return 1;
 }
 
-static int update_cipher_list(STACK_OF(SSL_CIPHER) **cipher_list,
+static int update_cipher_list(SSL_CTX *ctx,
+                              STACK_OF(SSL_CIPHER) **cipher_list,
                               STACK_OF(SSL_CIPHER) **cipher_list_by_id,
                               STACK_OF(SSL_CIPHER) *tls13_ciphersuites)
 {
@@ -1390,9 +1391,17 @@ static int update_cipher_list(STACK_OF(SSL_CIPHER) **cipher_list,
         (void)sk_SSL_CIPHER_delete(tmp_cipher_list, 0);
 
     /* Insert the new TLSv1.3 ciphersuites */
-    for (i = 0; i < sk_SSL_CIPHER_num(tls13_ciphersuites); i++)
-        sk_SSL_CIPHER_insert(tmp_cipher_list,
-                             sk_SSL_CIPHER_value(tls13_ciphersuites, i), i);
+    for (i = sk_SSL_CIPHER_num(tls13_ciphersuites) - 1; i >= 0; i--) {
+        const SSL_CIPHER *sslc = sk_SSL_CIPHER_value(tls13_ciphersuites, i);
+
+        /* Don't include any TLSv1.3 ciphersuites that are disabled */
+        if ((sslc->algorithm_enc & ctx->disabled_enc_mask) == 0
+                && (ssl_cipher_table_mac[sslc->algorithm2
+                                         & SSL_HANDSHAKE_MAC_MASK].mask
+                    & ctx->disabled_mac_mask) == 0) {
+            sk_SSL_CIPHER_unshift(tmp_cipher_list, sslc);
+        }
+    }
 
     if (!update_cipher_list_by_id(cipher_list_by_id, tmp_cipher_list)) {
         sk_SSL_CIPHER_free(tmp_cipher_list);
@@ -1410,7 +1419,7 @@ int SSL_CTX_set_ciphersuites(SSL_CTX *ctx, const char *str)
     int ret = set_ciphersuites(&(ctx->tls13_ciphersuites), str);
 
     if (ret && ctx->cipher_list != NULL)
-        return update_cipher_list(&ctx->cipher_list, &ctx->cipher_list_by_id,
+        return update_cipher_list(ctx, &ctx->cipher_list, &ctx->cipher_list_by_id,
                                   ctx->tls13_ciphersuites);
 
     return ret;
@@ -1426,7 +1435,7 @@ int SSL_set_ciphersuites(SSL *s, const char *str)
             s->cipher_list = sk_SSL_CIPHER_dup(cipher_list);
     }
     if (ret && s->cipher_list != NULL)
-        return update_cipher_list(&s->cipher_list, &s->cipher_list_by_id,
+        return update_cipher_list(s->ctx, &s->cipher_list, &s->cipher_list_by_id,
                                   s->tls13_ciphersuites);
 
     return ret;