api: binary api cleanup

Multiple API message handlers call vnet_get_sup_hw_interface(...)
without checking the inbound sw_if_index. This can cause a
pool_elt_at_index ASSERT in a debug image, and major disorder in a
production image.

Given that a number of places are coded as follows, add an
"api_visible_or_null" variant of vnet_get_sup_hw_interface, which
returns NULL given an invalid sw_if_index, or a hidden sw interface:

-  hw = vnet_get_sup_hw_interface (vnm, sw_if_index);
+  hw = vnet_get_sup_hw_interface_api_visible_or_null (vnm, sw_if_index);
   if (hw == NULL || memif_device_class.index != hw->dev_class_index)
     return clib_error_return (0, "not a memif interface");

Rename two existing xxx_safe functions -> xxx_or_null to make it
obvious what they return.

Type: fix

Change-Id: I29996e8d0768fd9e0c5495bd91ff8bedcf2c5697
Signed-off-by: Dave Barach <dave@barachs.net>
(cherry picked from commit 3940de36728b768574a3e998389bb90d55f690d1)

1 files changed, 3 insertions, 2 deletions

diff --git a/src/vnet/l2/l2_fib.c b/src/vnet/l2/l2_fib.c
index fc518fe9dbf..04fd975c319 100644
--- a/src/vnet/l2/l2_fib.c
+++ b/src/vnet/l2/l2_fib.c
@@ -95,12 +95,13 @@ format_vnet_sw_if_index_name_with_NA (u8 * s, va_list * args)
   if (sw_if_index == ~0)
     return format (s, "N/A");
 
-  vnet_sw_interface_t *swif = vnet_get_sw_interface_safe (vnm, sw_if_index);
+  vnet_sw_interface_t *swif =
+    vnet_get_sw_interface_or_null (vnm, sw_if_index);
   if (!swif)
     return format (s, "Stale");
 
   return format (s, "%U", format_vnet_sw_interface_name, vnm,
-		 vnet_get_sw_interface_safe (vnm, sw_if_index));
+		 vnet_get_sw_interface_or_null (vnm, sw_if_index));
 }
 
 typedef struct l2fib_dump_walk_ctx_t_