Latest update

ssl/statem/extensions.c

@@ -1198,7 +1198,7 @@ static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
                                                         X509 *x,
                                                         size_t chainidx)
 {
-    const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s);
+    const STACK_OF(X509_NAME) *ca_sk = get_ca_names(s);
 
     if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0)
         return EXT_RETURN_NOT_SENT;
@@ -1211,7 +1211,7 @@ static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
         return EXT_RETURN_FAIL;
     }
 
-    if (!construct_ca_names(s, pkt)) {
+    if (!construct_ca_names(s, ca_sk, pkt)) {
         /* SSLfatal() already called */
         return EXT_RETURN_FAIL;
     }

ssl/statem/statem_lib.c

@@ -1506,7 +1506,8 @@ static int ssl_method_error(const SSL *s, const SSL_METHOD *method)
  */
 static int is_tls13_capable(const SSL *s)
 {
-    int i;
+    int i, curve;
+    EC_KEY *eckey;
 
 #ifndef OPENSSL_NO_PSK
     if (s->psk_server_callback != NULL)
@@ -1527,7 +1528,20 @@ static int is_tls13_capable(const SSL *s)
         default:
             break;
         }
-        if (ssl_has_cert(s, i))
+        if (!ssl_has_cert(s, i))
+            continue;
+        if (i != SSL_PKEY_ECC)
+            return 1;
+        /*
+         * Prior to TLSv1.3 sig algs allowed any curve to be used. TLSv1.3 is
+         * more restrictive so check that our sig algs are consistent with this
+         * EC cert. See section 4.2.3 of RFC8446.
+         */
+        eckey = EVP_PKEY_get0_EC_KEY(s->cert->pkeys[SSL_PKEY_ECC].privatekey);
+        if (eckey == NULL)
+            continue;
+        curve = EC_GROUP_get_curve_name(EC_KEY_get0_group(eckey));
+        if (tls_check_sigalg_curve(s, curve))
             return 1;
     }
 
@@ -2295,10 +2309,24 @@ int parse_ca_names(SSL *s, PACKET *pkt)
     return 0;
 }
 
-int construct_ca_names(SSL *s, WPACKET *pkt)
+const STACK_OF(X509_NAME) *get_ca_names(SSL *s)
 {
-    const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s);
+    const STACK_OF(X509_NAME) *ca_sk = NULL;;
 
+    if (s->server) {
+        ca_sk = SSL_get_client_CA_list(s);
+        if (ca_sk != NULL && sk_X509_NAME_num(ca_sk) == 0)
+            ca_sk = NULL;
+    }
+
+    if (ca_sk == NULL)
+        ca_sk = SSL_get0_CA_list(s);
+
+    return ca_sk;
+}
+
+int construct_ca_names(SSL *s, const STACK_OF(X509_NAME) *ca_sk, WPACKET *pkt)
+{
     /* Start sub-packet for client CA list */
     if (!WPACKET_start_sub_packet_u16(pkt)) {
         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_CONSTRUCT_CA_NAMES,

ssl/statem/statem_locl.h

@@ -61,7 +61,8 @@ int create_synthetic_message_hash(SSL *s, const unsigned char *hashval,
                                   size_t hashlen, const unsigned char *hrr,
                                   size_t hrrlen);
 int parse_ca_names(SSL *s, PACKET *pkt);
-int construct_ca_names(SSL *s, WPACKET *pkt);
+const STACK_OF(X509_NAME) *get_ca_names(SSL *s);
+int construct_ca_names(SSL *s, const STACK_OF(X509_NAME) *ca_sk, WPACKET *pkt);
 size_t construct_key_exchange_tbs(SSL *s, unsigned char **ptbs,
                                   const void *param, size_t paramlen);
 

ssl/statem/statem_srvr.c

@@ -2881,7 +2881,7 @@ int tls_construct_certificate_request(SSL *s, WPACKET *pkt)
         }
     }
 
-    if (!construct_ca_names(s, pkt)) {
+    if (!construct_ca_names(s, get_ca_names(s), pkt)) {
         /* SSLfatal() already called */
         return 0;
     }