commit a32236c813a468a217b9355ce67314f8f7d73ed5
author Ronald Cron <ronald.cron@arm.com> Thu Apr 23 16:41:44 2020 +0200
committer Ronald Cron <ronald.cron@arm.com> Fri Jun 12 10:00:04 2020 +0200
tree 5f15a31b796942cac8f895f65db389a0cb753cf5
parent 20643557472ae3410f949231a86365dfe72f2926

Use defines to check alpn ext list validity

Signed-off-by: Ronald Cron <ronald.cron@arm.com>

include/mbedtls/ssl.h

diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 2c0c4dd..9ff5096 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -125,6 +125,9 @@
 #define MBEDTLS_SSL_TRANSPORT_DATAGRAM          1   /*!< DTLS     */
 
 #define MBEDTLS_SSL_MAX_HOST_NAME_LEN           255 /*!< Maximum host name defined in RFC 1035 */
+#define MBEDTLS_SSL_MAX_ALPN_NAME_LEN           255 /*!< Maximum size in bytes of a protocol name in alpn ext., RFC 7301 */
+
+#define MBEDTLS_SSL_MAX_ALPN_LIST_LEN           65535 /*!< Maximum size in bytes of list in alpn ext., RFC 7301          */
 
 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
  * NONE must be zero so that memset()ing structure to zero works */

library/ssl_tls.c

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 5f6ae62..60357e2 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -6526,7 +6526,9 @@
         cur_len = strlen( *p );
         tot_len += cur_len;
 
-        if( cur_len == 0 || cur_len > 255 || tot_len > 65535 )
+        if( ( cur_len == 0 ) ||
+            ( cur_len > MBEDTLS_SSL_MAX_ALPN_NAME_LEN ) ||
+            ( tot_len > MBEDTLS_SSL_MAX_ALPN_LIST_LEN ) )
             return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
     }