commit 459a46102dc1a98cf0f747c28a748a193722af95
author Dave Rodgman <dave.rodgman@arm.com> Mon Jun 28 21:58:56 2021 +0100
committer Dave Rodgman <dave.rodgman@arm.com> Tue Jun 29 09:44:35 2021 +0100
tree ab74300dd90233794823c4ed089c70f0a6dc993c
parent 438ef16d45064bfe23ad4314693bf372f39f49bf

Fix TLS alert codes

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>

ChangeLog.d/fix_tls_alert_codes.txt

diff --git a/ChangeLog.d/fix_tls_alert_codes.txt b/ChangeLog.d/fix_tls_alert_codes.txt
new file mode 100644
index 0000000..abe3a5e
--- /dev/null
+++ b/ChangeLog.d/fix_tls_alert_codes.txt
@@ -0,0 +1,6 @@
+Bugfix
+   * Fix the alert raised when a client requests an invalid
+   * fragment length, as per RFC6066 section 4. We now alert with
+   * MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER. Similarly, raise
+   * MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR for an invalid finished
+   * message, as per RFC5247 section 7.2.2.

library/ssl_cli.c

diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 073311b..7fedf17 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -1318,7 +1318,7 @@
         mbedtls_ssl_send_alert_message(
             ssl,
             MBEDTLS_SSL_ALERT_LEVEL_FATAL,
-            MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
+            MBEDTLS_SSL_ALERT_MSG_ILLEGAL_PARAMETER );
         return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
     }
 

library/ssl_tls.c

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 1a0794a..3c1e917 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -6684,7 +6684,7 @@
     {
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad finished message" ) );
         mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
-                                        MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
+                                        MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR );
         return( MBEDTLS_ERR_SSL_BAD_HS_FINISHED );
     }