ICMPv6: print RFC8335 PROBE extended echo/reply messages

[tcpdump] / print-ip.c

diff --git a/print-ip.c b/print-ip.c
index fab8e0b798ae6a602b959bf90964b8741204d47e..5edc62215e2751d4d5f4dfb65b517f6faaf191c0 100644 (file)
--- a/print-ip.c
+++ b/print-ip.c
@@ -21,9 +21,7 @@
 
 /* \summary: IP printer */
 
-#ifdef HAVE_CONFIG_H
 #include <config.h>
-#endif
 
 #include "netdissect-stdinc.h"
 
@@ -318,7 +316,7 @@ static const struct tok ip_frag_values[] = {
 void
 ip_print(netdissect_options *ndo,
         const u_char *bp,
-        u_int length)
+        const u_int length)
 {
        const struct ip *ip;
        u_int off;
@@ -329,6 +327,7 @@ ip_print(netdissect_options *ndo,
        uint16_t sum, ip_sum;
        const char *p_name;
        int truncated = 0;
+       int presumed_tso = 0;
 
        ndo->ndo_protocol = "ip";
        ip = (const struct ip *)bp;
@@ -341,32 +340,23 @@ ip_print(netdissect_options *ndo,
        ND_ICHECK_ZU(length, <, sizeof (struct ip));
        ND_ICHECKMSG_U("version", IP_V(ip), !=, 4);
 
-       ND_TCHECK_SIZE(ip);
        hlen = IP_HL(ip) * 4;
-       if (hlen < sizeof (struct ip)) {
-               ND_PRINT("bad-hlen %u", hlen);
-               return;
-       }
+       ND_ICHECKMSG_ZU("header length", hlen, <, sizeof (struct ip));
 
        len = GET_BE_U_2(ip->ip_len);
-       if (length < len)
-               ND_PRINT("truncated-ip - %u bytes missing! ",
-                       len - length);
-       if (len < hlen) {
-#ifdef GUESS_TSO
-            if (len) {
-                ND_PRINT("bad-len %u", len);
-                return;
-            } else {
-                /* we guess that it is a TSO send */
-                len = length;
-            }
-#else
-            ND_PRINT("bad-len %u", len);
-            return;
-#endif /* GUESS_TSO */
+       if (len > length) {
+               ND_PRINT("[total length %u > length %u]", len, length);
+               nd_print_invalid(ndo);
+               ND_PRINT(" ");
        }
+       if (len == 0) {
+               /* we guess that it is a TSO send */
+               len = length;
+               presumed_tso = 1;
+       } else
+               ND_ICHECKMSG_U("total length", len, <, hlen);
 
+       ND_TCHECK_SIZE(ip);
        /*
         * Cut off the snapshot length to the end of the IP payload.
         */
@@ -419,7 +409,10 @@ ip_print(netdissect_options *ndo,
                          tok2str(ipproto_values, "unknown", ip_proto),
                          ip_proto);
 
-            ND_PRINT(", length %u", GET_BE_U_2(ip->ip_len));
+           if (presumed_tso)
+                ND_PRINT(", length %u [was 0, presumed TSO]", length);
+           else
+                ND_PRINT(", length %u", GET_BE_U_2(ip->ip_len));
 
             if ((hlen - sizeof(struct ip)) > 0) {
                 ND_PRINT(", options (");