From 4420cb2f004b02eba2ef2055a3a67a97909d5938 Mon Sep 17 00:00:00 2001
From: gamemann <gamemann@gflclan.com>
Date: Fri, 18 Dec 2020 18:53:10 +0000
Subject: [PATCH] Improve ICMP matching.

---
 src/xdpfw_kern.c | 51 +++++++++++++++++++++++-------------------------
 1 file changed, 24 insertions(+), 27 deletions(-)

diff --git a/src/xdpfw_kern.c b/src/xdpfw_kern.c
index 88a1058..8747ad4 100644
--- a/src/xdpfw_kern.c
+++ b/src/xdpfw_kern.c
@@ -563,38 +563,35 @@ int xdp_prog_main(struct xdp_md *ctx)
         }
         else if (filter->icmpopts.enabled)
         {
-            if (!icmph)
+            if (icmph)
             {
-                continue;
-            }
+                // Code.
+                if (filter->icmpopts.do_code && filter->icmpopts.code != icmph->code)
+                {
+                    continue;
+                }
 
-            // Code.
-            if (filter->icmpopts.do_code && filter->icmpopts.code != icmph->code)
-            {
-                continue;
+                // Type.
+                if (filter->icmpopts.do_type && filter->icmpopts.type != icmph->type)
+                {
+                    continue;
+                }  
             }
+            else if (icmp6h)
+            {
+                // Code.
+                if (filter->icmpopts.do_code && filter->icmpopts.code != icmp6h->icmp6_code)
+                {
+                    continue;
+                }
 
-            // Type.
-            if (filter->icmpopts.do_type && filter->icmpopts.type != icmph->type)
-            {
-                continue;
-            }  
-        }
-        else if (icmp6h && filter->icmpopts.enabled)
-        {
-            if (!icmp6h)
-            {
-                continue;
+                // Type.
+                if (filter->icmpopts.do_type && filter->icmpopts.type != icmp6h->icmp6_type)
+                {
+                    continue;
+                }
             }
-
-            // Code.
-            if (filter->icmpopts.do_code && filter->icmpopts.code != icmp6h->icmp6_code)
-            {
-                continue;
-            }
-
-            // Type.
-            if (filter->icmpopts.do_type && filter->icmpopts.type != icmp6h->icmp6_type)
+            else
             {
                 continue;
             }