From 4ea1c703de90c11e6b40d1914e67bc5b23018072 Mon Sep 17 00:00:00 2001
From: dmiller <dmiller@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Tue, 12 May 2026 14:35:30 +0000
Subject: [PATCH] export various protocol header info functions

---
 libnetutil/netutil.h      | 10 ++++++++++
 libnetutil/packettrace.cc | 28 +++++++++-------------------
 2 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/libnetutil/netutil.h b/libnetutil/netutil.h
index 187400145..8d0a6a5b4 100644
--- a/libnetutil/netutil.h
+++ b/libnetutil/netutil.h
@@ -441,6 +441,16 @@ char *format_ip_options(const u8* ipopt, int ipoptlen);
 #define MEDIUM_DETAIL  2
 #define HIGH_DETAIL    3
 const char *ippackethdrinfo(const u8 *packet, u32 len, int detail);
+const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
+    int frag_off, const char *srchost, const char *dsthost);
+const char *udphdrinfo (const u8 *data, unsigned int datalen, int detail,
+    int frag_off, const char *srchost, const char *dsthost);
+const char *sctphdrinfo (const u8 *data, unsigned int datalen, int detail,
+    int frag_off, const char *srchost, const char *dsthost);
+const char *icmphdrinfo (const u8 *data, unsigned int datalen, int detail,
+    int frag_off, const char *srchost, const char *dsthost);
+const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
+    int frag_off, const char *srchost, const char *dsthost);
 
 
 /* Takes an IPv4 destination address (dst) and tries to determine the
diff --git a/libnetutil/packettrace.cc b/libnetutil/packettrace.cc
index 90485b704..0cb8079b6 100644
--- a/libnetutil/packettrace.cc
+++ b/libnetutil/packettrace.cc
@@ -478,16 +478,6 @@ static int tcpflagsinfo (char *buf, int len, u8 f) {
   return (p - buf);
 }
 
-const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
-    int frag_off, const char *srchost, const char *dsthost);
-const char *udphdrinfo (const u8 *data, unsigned int datalen, int detail,
-    int frag_off, const char *srchost, const char *dsthost);
-const char *sctphdrinfo (const u8 *data, unsigned int datalen, int detail,
-    int frag_off, const char *srchost, const char *dsthost);
-const char *icmphdrinfo (const u8 *data, unsigned int datalen, int detail,
-    int frag_off, const char *srchost, const char *dsthost);
-const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
-    int frag_off, const char *srchost, const char *dsthost);
 /* Returns a buffer of ASCII information about an IP packet that may
  * look like "TCP 127.0.0.1:50923 > 127.0.0.1:3 S ttl=61 id=39516
  * iplen=40 seq=625950769" or "ICMP PING (0/1) ttl=61 id=39516 iplen=40".
@@ -544,7 +534,7 @@ const char *ippackethdrinfo(const u8 *packet, u32 len, int detail) {
     sin = (struct sockaddr_in *) &hdr.src;
     inet_ntop(AF_INET, (void *)&sin->sin_addr.s_addr, srchost, sizeof(srchost));
     sin = (struct sockaddr_in *) &hdr.dst;
-	inet_ntop(AF_INET, (void *)&sin->sin_addr.s_addr, dsthost, sizeof(dsthost));
+    inet_ntop(AF_INET, (void *)&sin->sin_addr.s_addr, dsthost, sizeof(dsthost));
 
     /* Compute fragment offset and check if flags are set */
     frag_off = 8 * (ntohs(ip.ip_off) & 8191) /* 2^13 - 1 */;
@@ -595,9 +585,9 @@ const char *ippackethdrinfo(const u8 *packet, u32 len, int detail) {
 
     /* Obtain IP source and destination info */
     sin6 = (struct sockaddr_in6 *) &hdr.src;
-	inet_ntop(AF_INET6, (void *)sin6->sin6_addr.s6_addr, srchost, sizeof(srchost));
+    inet_ntop(AF_INET6, (void *)sin6->sin6_addr.s6_addr, srchost, sizeof(srchost));
     sin6 = (struct sockaddr_in6 *) &hdr.dst;
-	inet_ntop(AF_INET6, (void *)sin6->sin6_addr.s6_addr, dsthost, sizeof(dsthost));
+    inet_ntop(AF_INET6, (void *)sin6->sin6_addr.s6_addr, dsthost, sizeof(dsthost));
 
     /* Obtain flow label and traffic class */
     u32 flow = ntohl(ip6.ip6_flow);
@@ -692,7 +682,7 @@ const char *tcphdrinfo (const u8 *data, unsigned int datalen, int detail,
    * either the fragment belongs to somewhere past that or the IP contains
    * less than 8 bytes. This also includes empty IP packets that say they
    * contain a TCP packet. */
-  if (frag_off > 8 || datalen < 8) {
+  if (frag_off > 8 || datalen < 8 || (frag_off % 8 != 0)) {
     Snprintf(protoinfo, sizeof(protoinfo), "TCP %s:?? > %s:?? ?? (incomplete)",
         srchost, dsthost);
   }
@@ -1177,7 +1167,11 @@ const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
   if (dsthost == NULL)
     dsthost = "??";
   static char protoinfo[512] = "";
-  if (datalen > sizeof(struct icmpv6_hdr)) {
+  if (frag_off || datalen < sizeof(struct icmpv6_hdr)) {
+    Snprintf(protoinfo, sizeof(protoinfo), "ICMPv6 %s > %s (type=?/code=?)",
+        srchost, dsthost);
+  }
+  else {
     const struct icmpv6_hdr *icmpv6;
 
     icmpv6 = (struct icmpv6_hdr *) data;
@@ -1185,10 +1179,6 @@ const char *icmp6hdrinfo (const u8 *data, unsigned int datalen, int detail,
         srchost, dsthost,
         icmpv6->icmpv6_type, icmpv6->icmpv6_code);
   }
-  else {
-    Snprintf(protoinfo, sizeof(protoinfo), "ICMPv6 %s > %s (type=?/code=?)",
-        srchost, dsthost);
-  }
   return protoinfo;
 }