api: verify message size on receipt

When a message is received, verify that it's sufficiently large to
accomodate any VLAs within message. To do that, we need a way to
calculate message size including any VLAs. This patch adds such
funcionality to vppapigen and necessary C code to use those to validate
message size on receipt. Drop messages which are malformed.

Type: improvement
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: I2903aa21dee84be6822b064795ba314de46c18f4

1 files changed, 6 insertions, 1 deletions

diff --git a/src/vcl/vcl_bapi.c b/src/vcl/vcl_bapi.c
index 72440989727..bb2b94f04d8 100644
--- a/src/vcl/vcl_bapi.c
+++ b/src/vcl/vcl_bapi.c
@@ -276,6 +276,10 @@ vl_api_app_del_cert_key_pair_reply_t_handler (
 #include <vnet/session/session.api.h>
 #undef vl_endianfun
 
+#define vl_calcsizefun
+#include <vnet/session/session.api.h>
+#undef vl_calcsizefun
+
 /* instantiate all the print functions we know about */
 #define vl_printfun
 #include <vnet/session/session.api.h>
@@ -303,7 +307,8 @@ vcl_bapi_hookup (void)
     REPLY_MSG_ID_BASE + VL_API_##N, #n, vl_api_##n##_t_handler,               \
     vl_noop_handler, vl_api_##n##_t_endian, vl_api_##n##_t_print,             \
     sizeof (vl_api_##n##_t), 1, vl_api_##n##_t_print_json,                    \
-    vl_api_##n##_t_tojson, vl_api_##n##_t_fromjson);
+    vl_api_##n##_t_tojson, vl_api_##n##_t_fromjson,                           \
+    vl_api_##n##_t_calc_size);
   foreach_sock_msg;
 #undef _
 }