Handle very large -f files by rejecting them.

[tcpdump] / print-frag6.c

diff --git a/print-frag6.c b/print-frag6.c
index cc057ba77be2ece218ab11a25ba53b03dacf97b6..fbcabc5b00cdc82a97ca76e7f15ca94823f40561 100644 (file)
--- a/print-frag6.c
+++ b/print-frag6.c
@@ -19,78 +19,52 @@
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
-#ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-frag6.c,v 1.9 2000-09-28 06:42:59 guy Exp $";
-#endif
+/* \summary: IPv6 fragmentation header printer */
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#ifdef INET6
-
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-
-
-#include <netinet/in.h>
-#include <netinet/in_systm.h>
-
-#include <stdio.h>
+#include <netdissect-stdinc.h>
 
-#include <netinet/ip6.h>
+#include "netdissect.h"
+#include "extract.h"
 
-#include "interface.h"
-#include "addrtoname.h"
+#include "ip6.h"
 
 int
-frag6_print(register const u_char *bp, register const u_char *bp2)
+frag6_print(netdissect_options *ndo, register const u_char *bp, register const u_char *bp2)
 {
        register const struct ip6_frag *dp;
        register const struct ip6_hdr *ip6;
-       register const u_char *ep;
 
-#if 0
-#define TCHECK(var) if ((u_char *)&(var) >= ep - sizeof(var)) goto trunc
-#endif
-
-       dp = (struct ip6_frag *)bp;
-       ip6 = (struct ip6_hdr *)bp2;
+       dp = (const struct ip6_frag *)bp;
+       ip6 = (const struct ip6_hdr *)bp2;
 
-       /* 'ep' points to the end of avaible data. */
-       ep = snapend;
+       ND_TCHECK(*dp);
 
-       TCHECK(dp->ip6f_offlg);
-
-       if (vflag) {
-               printf("frag (0x%08x:%d|%ld)",
-                      (u_int32_t)ntohl(dp->ip6f_ident),
-                      ntohs(dp->ip6f_offlg & IP6F_OFF_MASK),
-                      sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) -
-                              (long)(bp - bp2) - sizeof(struct ip6_frag));
+       if (ndo->ndo_vflag) {
+               ND_PRINT((ndo, "frag (0x%08x:%d|%ld)",
+                      EXTRACT_32BITS(&dp->ip6f_ident),
+                      EXTRACT_16BITS(&dp->ip6f_offlg) & IP6F_OFF_MASK,
+                      sizeof(struct ip6_hdr) + EXTRACT_16BITS(&ip6->ip6_plen) -
+                              (long)(bp - bp2) - sizeof(struct ip6_frag)));
        } else {
-               printf("frag (%d|%ld)",
-                      ntohs(dp->ip6f_offlg & IP6F_OFF_MASK),
-                      sizeof(struct ip6_hdr) + ntohs(ip6->ip6_plen) -
-                              (long)(bp - bp2) - sizeof(struct ip6_frag));
+               ND_PRINT((ndo, "frag (%d|%ld)",
+                      EXTRACT_16BITS(&dp->ip6f_offlg) & IP6F_OFF_MASK,
+                      sizeof(struct ip6_hdr) + EXTRACT_16BITS(&ip6->ip6_plen) -
+                              (long)(bp - bp2) - sizeof(struct ip6_frag)));
        }
 
-#if 1
        /* it is meaningless to decode non-first fragment */
-       if (ntohs(dp->ip6f_offlg & IP6F_OFF_MASK) != 0)
-               return 65535;
+       if ((EXTRACT_16BITS(&dp->ip6f_offlg) & IP6F_OFF_MASK) != 0)
+               return -1;
        else
-#endif
        {
-               fputs(" ", stdout);
+               ND_PRINT((ndo, " "));
                return sizeof(struct ip6_frag);
        }
 trunc:
-       fputs("[|frag]", stdout);
-       return 65535;
-#undef TCHECK
+       ND_PRINT((ndo, "[|frag]"));
+       return -1;
 }
-#endif /* INET6 */