Only send custom extensions where we have received one in the ClientHello

We already did this for ServerHello and EncryptedExtensions. We should be
doing it for Certificate and HelloRetryRequest as well.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3298)

diff --git a/ssl/statem/extensions_cust.c b/ssl/statem/extensions_cust.c
index 6de59e2425f8769e451d09ff327d94b1d7b641b4..2a21ec492ca7045cc0cdc59aa0e7190e9aa43f84 100644 (file)
--- a/ssl/statem/extensions_cust.c
+++ b/ssl/statem/extensions_cust.c
@@ -181,11 +181,10 @@ int custom_ext_add(SSL *s, int context, WPACKET *pkt, X509 *x, size_t chainidx,
 
         if ((context & (SSL_EXT_TLS1_2_SERVER_HELLO
                         | SSL_EXT_TLS1_3_SERVER_HELLO
-                        | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS)) != 0) {
-            /*
-             * For ServerHello/EncryptedExtensions only send extensions present
-             * in ClientHello.
-             */
+                        | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
+                        | SSL_EXT_TLS1_3_CERTIFICATE
+                        | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST)) != 0) {
+            /* Only send extensions present in ClientHello. */
             if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED))
                 continue;
         }