lib: handle bogus VRF backend type

And use an enum...

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

3 files changed, 24 insertions, 9 deletions

diff --git a/lib/vrf.c b/lib/vrf.c
index 31ea2d6c4c..fc5aa8f2b6 100644
--- a/lib/vrf.c
+++ b/lib/vrf.c
@@ -593,10 +593,15 @@ int vrf_get_backend(void)
 	return vrf_backend;
 }
 
-void vrf_configure_backend(int vrf_backend_netns)
+int vrf_configure_backend(enum vrf_backend_type backend)
 {
-	vrf_backend = vrf_backend_netns;
+	if (backend > VRF_BACKEND_MAX)
+		return -1;
+
+	vrf_backend = backend;
 	vrf_backend_configured = 1;
+
+	return 0;
 }
 
 int vrf_handler_create(struct vty *vty, const char *vrfname,
diff --git a/lib/vrf.h b/lib/vrf.h
index f231d2433f..2dc2648837 100644
--- a/lib/vrf.h
+++ b/lib/vrf.h
@@ -101,9 +101,12 @@ RB_PROTOTYPE(vrf_name_head, vrf, name_entry, vrf_name_compare)
 DECLARE_QOBJ_TYPE(vrf)
 
 /* Allow VRF with netns as backend */
-#define VRF_BACKEND_VRF_LITE   0
-#define VRF_BACKEND_NETNS      1
-#define VRF_BACKEND_UNKNOWN    2
+enum vrf_backend_type {
+	VRF_BACKEND_VRF_LITE,
+	VRF_BACKEND_NETNS,
+	VRF_BACKEND_UNKNOWN,
+	VRF_BACKEND_MAX,
+};
 
 extern struct vrf_id_head vrfs_by_id;
 extern struct vrf_name_head vrfs_by_name;
@@ -292,10 +295,10 @@ extern void vrf_install_commands(void);
  * VRF utilities
  */
 
-/* API for configuring VRF backend
- * should be called from zebra only
+/*
+ * API for configuring VRF backend
  */
-extern void vrf_configure_backend(int vrf_backend_netns);
+extern int vrf_configure_backend(enum vrf_backend_type backend);
 extern int vrf_get_backend(void);
 extern int vrf_is_backend_netns(void);
 
diff --git a/lib/zclient.c b/lib/zclient.c
index b32be1c310..673e71c515 100644
--- a/lib/zclient.c
+++ b/lib/zclient.c
@@ -3031,7 +3031,14 @@ static void zclient_capability_decode(ZAPI_CALLBACK_ARGS)
 	uint8_t mpls_enabled;
 
 	STREAM_GETL(s, vrf_backend);
-	vrf_configure_backend(vrf_backend);
+
+	if (vrf_backend < 0 || vrf_configure_backend(vrf_backend)) {
+		flog_err(EC_LIB_ZAPI_ENCODE,
+			 "%s: Garbage VRF backend type: %d\n", __func__,
+			 vrf_backend);
+		goto stream_failure;
+	}
+
 
 	memset(&cap, 0, sizeof(cap));
 	STREAM_GETC(s, mpls_enabled);