commit d2fc90e024b055e023c412fac6a1377229396eff
author Waleed Elmelegy <waleed.elmelegy@arm.com> Thu Jan 04 18:04:53 2024 +0000
committer Waleed Elmelegy <waleed.elmelegy@arm.com> Wed Jan 10 16:17:27 2024 +0000
tree 2202f193d3556dbfd5031bfdc00e1ca39796e720
parent 148dfb64575dab43a26fe66677d2b7f98d22f049

Stop sending record size limit extension if it's not sent from client

Signed-off-by: Waleed Elmelegy <waleed.elmelegy@arm.com>

library/ssl_tls13_server.c

diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index c9fddda..36d1c05 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -2500,6 +2500,9 @@
     size_t extensions_len = 0;
     unsigned char *p_extensions_len;
     size_t output_len;
+#if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
+    uint32_t record_size_extension_mask;
+#endif
 
     *out_len = 0;
 
@@ -2531,12 +2534,15 @@
 #endif /* MBEDTLS_SSL_EARLY_DATA */
 
 #if defined(MBEDTLS_SSL_RECORD_SIZE_LIMIT)
-    ret = mbedtls_ssl_tls13_write_record_size_limit_ext(
-        ssl, MBEDTLS_SSL_IN_CONTENT_LEN, p, end, &output_len);
-    if (ret != 0) {
-        return ret;
+    record_size_extension_mask = mbedtls_ssl_get_extension_mask(MBEDTLS_TLS_EXT_RECORD_SIZE_LIMIT);
+    if (ssl->handshake->received_extensions | record_size_extension_mask) {
+        ret = mbedtls_ssl_tls13_write_record_size_limit_ext(
+            ssl, p, end, &output_len);
+        if (ret != 0) {
+            return ret;
+        }
+        p += output_len;
     }
-    p += output_len;
 #endif
 
     extensions_len = (p - p_extensions_len) - 2;