From 2fa55a86faa088221ffb537e65377cfbfce58288 Mon Sep 17 00:00:00 2001
From: Anoop Saldanha <poonaatsoc@gmail.com>
Date: Wed, 1 Feb 2012 14:44:01 +0530
Subject: [PATCH] Fix csum validation functions to not carry out csum
 calculation if respective headers are not present

---
 src/detect-csum.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/detect-csum.c b/src/detect-csum.c
index f9e1beef8f..f0f4655f97 100644
--- a/src/detect-csum.c
+++ b/src/detect-csum.c
@@ -324,7 +324,7 @@ int DetectTCPV4CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip4h == NULL || p->proto != IPPROTO_TCP || PKT_IS_PSEUDOPKT(p))
+    if (p->ip4h == NULL || p->tcph == NULL || p->proto != IPPROTO_TCP || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {
@@ -419,7 +419,7 @@ int DetectTCPV6CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip6h == NULL || p->proto != IPPROTO_TCP || PKT_IS_PSEUDOPKT(p))
+    if (p->ip6h == NULL || p->tcph == NULL || p->proto != IPPROTO_TCP || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {
@@ -514,7 +514,7 @@ int DetectUDPV4CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip4h == NULL || p->proto != IPPROTO_UDP || PKT_IS_PSEUDOPKT(p))
+    if (p->ip4h == NULL || p->udph == NULL || p->proto != IPPROTO_UDP || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {
@@ -610,7 +610,7 @@ int DetectUDPV6CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip6h == NULL || p->proto != IPPROTO_UDP || PKT_IS_PSEUDOPKT(p))
+    if (p->ip6h == NULL || p->udph == NULL || p->proto != IPPROTO_UDP || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {
@@ -706,7 +706,7 @@ int DetectICMPV4CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip4h == NULL || p->proto != IPPROTO_ICMP || PKT_IS_PSEUDOPKT(p))
+    if (p->ip4h == NULL || p->icmpv4h == NULL || p->proto != IPPROTO_ICMP || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {
@@ -801,7 +801,7 @@ int DetectICMPV6CsumMatch(ThreadVars *t, DetectEngineThreadCtx *det_ctx,
 {
     DetectCsumData *cd = (DetectCsumData *)m->ctx;
 
-    if (p->ip6h == NULL || p->proto != IPPROTO_ICMPV6 || PKT_IS_PSEUDOPKT(p))
+    if (p->ip6h == NULL || p->icmpv6h == NULL || p->proto != IPPROTO_ICMPV6 || PKT_IS_PSEUDOPKT(p))
         return 0;
 
     if (p->flags & PKT_IGNORE_CHECKSUM) {