pimd: Don't allow invalid groups to be passed for igmp

When we receive a invalid group( say outside of the 224/4
range) don't allow it to create state.  Nicely reject
the rejectable.

Ticket: CM-13821
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/pimd/pim_util.c b/pimd/pim_util.c
index daee941f8b..f5255a241d 100644
--- a/pimd/pim_util.c
+++ b/pimd/pim_util.c
@@ -22,6 +22,7 @@
 #include <zebra.h>
 
 #include "log.h"
+#include "prefix.h"
 
 #include "pim_util.h"
 
@@ -104,3 +105,20 @@ void pim_pkt_dump(const char *label, const uint8_t *buf, int size)
 	     size);
   zlog_hexdump(buf, size);
 }
+
+int
+pim_is_group_224_4 (struct in_addr group_addr)
+{
+  static int first = 1;
+  static struct prefix group_all;
+  struct prefix group;
+
+  if (first)
+    str2prefix ("224.0.0.0/4", &group_all);
+
+  group.family = AF_INET;
+  group.u.prefix4 = group_addr;
+  group.prefixlen = 32;
+
+  return prefix_match (&group_all, &group);
+}