]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-ip.c
Fix the pointer tests in the non-ndoified TTEST2() macro as well.
[tcpdump] / print-ip.c
index 505cf847b665b9f5b9c6969aa44357ef7cf93dc2..acf3bd8be9fe0de2a466231ed54087ac960c7e92 100644 (file)
  */
 
 #ifndef lint
-static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.89 2000-10-03 02:54:58 itojun Exp $ (LBL)";
+static const char rcsid[] _U_ =
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ip.c,v 1.159 2007-09-14 01:29:28 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include <sys/param.h>
-#include <sys/time.h>
-#include <sys/socket.h>
-
-#include <netinet/in.h>
+#include <tcpdump-stdinc.h>
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
 #include "addrtoname.h"
 #include "interface.h"
 #include "extract.h"                   /* must come after interface.h */
 
 #include "ip.h"
-
-/* Compatibility */
-#ifndef        IPPROTO_ND
-#define        IPPROTO_ND      77
-#endif
-
-#ifndef IN_CLASSD
-#define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
-#endif
-
-/* (following from ipmulti/mrouted/prune.h) */
-
-/*
- * The packet format for a traceroute request.
- */
-struct tr_query {
-       u_int  tr_src;                  /* traceroute source */
-       u_int  tr_dst;                  /* traceroute destination */
-       u_int  tr_raddr;                /* traceroute response address */
-       u_int  tr_rttlqid;              /* response ttl and qid */
+#include "ipproto.h"
+
+struct tok ip_option_values[] = {
+    { IPOPT_EOL, "EOL" },
+    { IPOPT_NOP, "NOP" },
+    { IPOPT_TS, "timestamp" },
+    { IPOPT_SECURITY, "security" },
+    { IPOPT_RR, "RR" },
+    { IPOPT_SSRR, "SSRR" },
+    { IPOPT_LSRR, "LSRR" },
+    { IPOPT_RA, "RA" },
+    { IPOPT_RFC1393, "traceroute" },
+    { 0, NULL }
 };
 
-#define TR_GETTTL(x)           (int)(((x) >> 24) & 0xff)
-#define TR_GETQID(x)           ((x) & 0x00ffffff)
-
 /*
- * Traceroute response format.  A traceroute response has a tr_query at the
- * beginning, followed by one tr_resp for each hop taken.
+ * print the recorded route in an IP RR, LSRR or SSRR option.
  */
-struct tr_resp {
-       u_int tr_qarr;                  /* query arrival time */
-       u_int tr_inaddr;                /* incoming interface address */
-       u_int tr_outaddr;               /* outgoing interface address */
-       u_int tr_rmtaddr;               /* parent address in source tree */
-       u_int tr_vifin;                 /* input packet count on interface */
-       u_int tr_vifout;                /* output packet count on interface */
-       u_int tr_pktcnt;                /* total incoming packets for src-grp */
-       u_char  tr_rproto;              /* routing proto deployed on router */
-       u_char  tr_fttl;                /* ttl required to forward on outvif */
-       u_char  tr_smask;               /* subnet mask for src addr */
-       u_char  tr_rflags;              /* forwarding error codes */
-};
-
-/* defs within mtrace */
-#define TR_QUERY 1
-#define TR_RESP        2
-
-/* fields for tr_rflags (forwarding error codes) */
-#define TR_NO_ERR      0
-#define TR_WRONG_IF    1
-#define TR_PRUNED      2
-#define TR_OPRUNED     3
-#define TR_SCOPED      4
-#define TR_NO_RTE      5
-#define TR_NO_FWD      7
-#define TR_NO_SPACE    0x81
-#define TR_OLD_ROUTER  0x82
-
-/* fields for tr_rproto (routing protocol) */
-#define TR_PROTO_DVMRP 1
-#define TR_PROTO_MOSPF 2
-#define TR_PROTO_PIM   3
-#define TR_PROTO_CBT   4
-
-static void print_mtrace(register const u_char *bp, register u_int len)
-{
-       register struct tr_query *tr = (struct tr_query *)(bp + 8);
-
-       printf("mtrace %lu: %s to %s reply-to %s",
-               (u_long)TR_GETQID(ntohl(tr->tr_rttlqid)),
-               ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
-               ipaddr_string(&tr->tr_raddr));
-       if (IN_CLASSD(ntohl(tr->tr_raddr)))
-               printf(" with-ttl %d", TR_GETTTL(ntohl(tr->tr_rttlqid)));
-}
-
-static void print_mresp(register const u_char *bp, register u_int len)
-{
-       register struct tr_query *tr = (struct tr_query *)(bp + 8);
-
-       printf("mresp %lu: %s to %s reply-to %s",
-               (u_long)TR_GETQID(ntohl(tr->tr_rttlqid)),
-               ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
-               ipaddr_string(&tr->tr_raddr));
-       if (IN_CLASSD(ntohl(tr->tr_raddr)))
-               printf(" with-ttl %d", TR_GETTTL(ntohl(tr->tr_rttlqid)));
-}
-
 static void
-igmp_print(register const u_char *bp, register u_int len,
-          register const u_char *bp2)
+ip_printroute(register const u_char *cp, u_int length)
 {
-       register const struct ip *ip;
-
-       ip = (const struct ip *)bp2;
-        (void)printf("%s > %s: ",
-               ipaddr_string(&ip->ip_src),
-               ipaddr_string(&ip->ip_dst));
+       register u_int ptr;
+       register u_int len;
 
-       if (qflag) {
-               (void)printf("igmp");
+       if (length < 3) {
+               printf(" [bad length %u]", length);
                return;
        }
+       if ((length + 1) & 3)
+               printf(" [bad length %u]", length);
+       ptr = cp[2] - 1;
+       if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
+               printf(" [bad ptr %u]", cp[2]);
 
-       TCHECK2(bp[0], 8);
-       switch (bp[0]) {
-       case 0x11:
-               (void)printf("igmp query");
-               if (EXTRACT_32BITS(&bp[4]))
-                       (void)printf(" [gaddr %s]", ipaddr_string(&bp[4]));
-               if (len != 8)
-                       (void)printf(" [len %d]", len);
-               break;
-       case 0x12:
-               (void)printf("igmp v1 report %s", ipaddr_string(&bp[4]));
-               if (len != 8)
-                       (void)printf(" [len %d]", len);
-               break;
-       case 0x16:
-               (void)printf("igmp v2 report %s", ipaddr_string(&bp[4]));
-               break;
-       case 0x17:
-               (void)printf("igmp leave %s", ipaddr_string(&bp[4]));
-               break;
-       case 0x13:
-               (void)printf("igmp dvmrp");
-               if (len < 8)
-                       (void)printf(" [len %d]", len);
-               else
-                       dvmrp_print(bp, len);
-               break;
-       case 0x14:
-               (void)printf("igmp pimv1");
-               pimv1_print(bp, len);
-               break;
-       case 0x1e:
-               print_mresp(bp, len);
-               break;
-       case 0x1f:
-               print_mtrace(bp, len);
-               break;
-       default:
-               (void)printf("igmp-%d", bp[0]);
-               break;
-       }
-
-       if (vflag && TTEST2(bp[0], len)) {
-               /* Check the IGMP checksum */
-               if (in_cksum((const u_short*)bp, len, 0))
-                       printf(" bad igmp cksum %x!", EXTRACT_16BITS(&bp[2]));
+       for (len = 3; len < length; len += 4) {
+               printf(" %s", ipaddr_string(&cp[len]));
+                if (ptr > len)
+                        printf(",");
        }
-       return;
-trunc:
-       fputs("[|igmp]", stdout);
 }
 
 /*
- * print the recorded route in an IP RR, LSRR or SSRR option.
+ * If source-routing is present and valid, return the final destination.
+ * Otherwise, return IP destination.
+ *
+ * This is used for UDP and TCP pseudo-header in the checksum
+ * calculation.
  */
-static void
-ip_printroute(const char *type, register const u_char *cp, u_int length)
+u_int32_t
+ip_finddst(const struct ip *ip)
 {
-       register u_int ptr = cp[2] - 1;
-       register u_int len;
+       int length;
+       int len;
+       const u_char *cp;
+       u_int32_t retval;
 
-       printf(" %s{", type);
-       if ((length + 1) & 3)
-               printf(" [bad length %d]", length);
-       if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
-               printf(" [bad ptr %d]", cp[2]);
+       cp = (const u_char *)(ip + 1);
+       length = (IP_HL(ip) << 2) - sizeof(struct ip);
 
-       type = "";
-       for (len = 3; len < length; len += 4) {
-               if (ptr == len)
-                       type = "#";
-               printf("%s%s", type, ipaddr_string(&cp[len]));
-               type = " ";
+       for (; length > 0; cp += len, length -= len) {
+               int tt;
+
+               TCHECK(*cp);
+               tt = *cp;
+               if (tt == IPOPT_EOL)
+                       break;
+               else if (tt == IPOPT_NOP)
+                       len = 1;
+               else {
+                       TCHECK(cp[1]);
+                       len = cp[1];
+                       if (len < 2)
+                               break;
+               }
+               TCHECK2(*cp, len);
+               switch (tt) {
+
+               case IPOPT_SSRR:
+               case IPOPT_LSRR:
+                       if (len < 7)
+                               break;
+                       memcpy(&retval, cp + len - 4, 4);
+                       return retval;
+               }
        }
-       printf("%s}", ptr == len? "#" : "");
+trunc:
+       memcpy(&retval, &ip->ip_dst.s_addr, sizeof(u_int32_t));
+       return retval;
 }
 
 static void
 ip_printts(register const u_char *cp, u_int length)
 {
-       register u_int ptr = cp[2] - 1;
-       register u_int len = 0;
+       register u_int ptr;
+       register u_int len;
        int hoplen;
-       char *type;
+       const char *type;
 
+       if (length < 4) {
+               printf("[bad length %u]", length);
+               return;
+       }
        printf(" TS{");
        hoplen = ((cp[3]&0xF) != IPOPT_TS_TSONLY) ? 8 : 4;
        if ((length - 4) & (hoplen-1))
-               printf("[bad length %d]", length);
+               printf("[bad length %u]", length);
+       ptr = cp[2] - 1;
+       len = 0;
        if (ptr < 4 || ((ptr - 4) & (hoplen-1)) || ptr > length + 1)
-               printf("[bad ptr %d]", cp[2]);
+               printf("[bad ptr %u]", cp[2]);
        switch (cp[3]&0xF) {
        case IPOPT_TS_TSONLY:
                printf("TSONLY");
@@ -258,7 +168,7 @@ ip_printts(register const u_char *cp, u_int length)
        case 3:                 /* IPOPT_TS_PRESPEC */
                printf("PRESPEC");
                break;
-       default:        
+       default:
                printf("[bad ts type %d]", cp[3]&0xF);
                goto done;
        }
@@ -287,79 +197,75 @@ done:
 static void
 ip_optprint(register const u_char *cp, u_int length)
 {
-       register u_int len;
+       register u_int option_len;
+       const char *sep = "";
 
-       for (; length > 0; cp += len, length -= len) {
-               int tt = *cp;
+       for (; length > 0; cp += option_len, length -= option_len) {
+               u_int option_code;
+
+               printf("%s", sep);
+               sep = ",";
+
+               TCHECK(*cp);
+               option_code = *cp;
+
+                printf("%s",
+                        tok2str(ip_option_values,"unknown %u",option_code));
+
+               if (option_code == IPOPT_NOP ||
+                    option_code == IPOPT_EOL)
+                       option_len = 1;
 
-               if (tt == IPOPT_NOP || tt == IPOPT_EOL)
-                       len = 1;
                else {
-                       if (&cp[1] >= snapend) {
-                               printf("[|ip]");
+                       TCHECK(cp[1]);
+                       option_len = cp[1];
+                       if (option_len < 2) {
+                               printf(" [bad length %u]", option_len);
                                return;
                        }
-                       len = cp[1];
-               }
-               if (len <= 0) {
-                       printf("[|ip op len %d]", len);
-                       return;
                }
-               if (&cp[1] >= snapend || cp + len > snapend) {
-                       printf("[|ip]");
+
+               if (option_len > length) {
+                       printf(" [bad length %u]", option_len);
                        return;
                }
-               switch (tt) {
 
+                TCHECK2(*cp, option_len);
+
+               switch (option_code) {
                case IPOPT_EOL:
-                       printf(" EOL");
-                       if (length > 1)
-                               printf("-%d", length - 1);
                        return;
 
-               case IPOPT_NOP:
-                       printf(" NOP");
-                       break;
-
                case IPOPT_TS:
-                       ip_printts(cp, len);
-                       break;
-
-#ifndef IPOPT_SECURITY
-#define IPOPT_SECURITY 130
-#endif /* IPOPT_SECURITY */
-               case IPOPT_SECURITY:
-                       printf(" SECURITY{%d}", len);
-                       break;
-
-               case IPOPT_RR:
-                       ip_printroute("RR", cp, len);
+                       ip_printts(cp, option_len);
                        break;
 
+               case IPOPT_RR:       /* fall through */
                case IPOPT_SSRR:
-                       ip_printroute("SSRR", cp, len);
-                       break;
-
                case IPOPT_LSRR:
-                       ip_printroute("LSRR", cp, len);
+                       ip_printroute(cp, option_len);
                        break;
 
-#ifndef IPOPT_RA
-#define IPOPT_RA 148           /* router alert */
-#endif
                case IPOPT_RA:
-                       printf(" RA");
-                       if (len != 4)
-                               printf("{%d}", len);
-                       else if (cp[2] || cp[3])
-                               printf("%d.%d", cp[2], cp[3]);
-                       break;
+                       if (option_len < 4) {
+                               printf(" [bad length %u]", option_len);
+                               break;
+                       }
+                        TCHECK(cp[3]);
+                        if (EXTRACT_16BITS(&cp[2]) != 0)
+                            printf(" value %u", EXTRACT_16BITS(&cp[2]));
+                       break;
 
+               case IPOPT_NOP:       /* nothing to print - fall through */
+               case IPOPT_SECURITY:
                default:
-                       printf(" IPOPT-%d{%d}", cp[0], len);
                        break;
                }
        }
+       return;
+
+trunc:
+       printf("[|ip]");
 }
 
 /*
@@ -367,19 +273,19 @@ ip_optprint(register const u_char *cp, u_int length)
  * don't modifiy the packet.
  */
 u_short
-in_cksum(const u_short *addr, register int len, u_short csum)
+in_cksum(const u_short *addr, register u_int len, int csum)
 {
        int nleft = len;
        const u_short *w = addr;
        u_short answer;
        int sum = csum;
 
-       /*
+       /*
         *  Our algorithm is simple, using a 32 bit accumulator (sum),
         *  we add sequential 16 bit words to it, and at the end, fold
         *  back all the carry bits from the top 16 bits into the lower
         *  16 bits.
-        */
+        */
        while (nleft > 1)  {
                sum += *w++;
                nleft -= 2;
@@ -397,331 +303,405 @@ in_cksum(const u_short *addr, register int len, u_short csum)
 }
 
 /*
- * print an IP datagram.
+ * Given the host-byte-order value of the checksum field in a packet
+ * header, and the network-byte-order computed checksum of the data
+ * that the checksum covers (including the checksum itself), compute
+ * what the checksum field *should* have been.
  */
-void
-ip_print(register const u_char *bp, register u_int length)
+u_int16_t
+in_cksum_shouldbe(u_int16_t sum, u_int16_t computed_sum)
 {
-       register const struct ip *ip;
-       register u_int hlen, len, len0, off;
-       register const u_char *cp;
-       u_char nh;
-       int advance;
-
-       ip = (const struct ip *)bp;
-#ifdef LBL_ALIGN
+       u_int32_t shouldbe;
+
        /*
-        * If the IP header is not aligned, copy into abuf.
-        * This will never happen with BPF.  It does happen raw packet
-        * dumps from -r.
+        * The value that should have gone into the checksum field
+        * is the negative of the value gotten by summing up everything
+        * *but* the checksum field.
+        *
+        * We can compute that by subtracting the value of the checksum
+        * field from the sum of all the data in the packet, and then
+        * computing the negative of that value.
+        *
+        * "sum" is the value of the checksum field, and "computed_sum"
+        * is the negative of the sum of all the data in the packets,
+        * so that's -(-computed_sum - sum), or (sum + computed_sum).
+        *
+        * All the arithmetic in question is one's complement, so the
+        * addition must include an end-around carry; we do this by
+        * doing the arithmetic in 32 bits (with no sign-extension),
+        * and then adding the upper 16 bits of the sum, which contain
+        * the carry, to the lower 16 bits of the sum, and then do it
+        * again in case *that* sum produced a carry.
+        *
+        * As RFC 1071 notes, the checksum can be computed without
+        * byte-swapping the 16-bit words; summing 16-bit words
+        * on a big-endian machine gives a big-endian checksum, which
+        * can be directly stuffed into the big-endian checksum fields
+        * in protocol headers, and summing words on a little-endian
+        * machine gives a little-endian checksum, which must be
+        * byte-swapped before being stuffed into a big-endian checksum
+        * field.
+        *
+        * "computed_sum" is a network-byte-order value, so we must put
+        * it in host byte order before subtracting it from the
+        * host-byte-order value from the header; the adjusted checksum
+        * will be in host byte order, which is what we'll return.
         */
-       if ((long)ip & 3) {
-               static u_char *abuf = NULL;
-               static int didwarn = 0;
-
-               if (abuf == NULL) {
-                       abuf = (u_char *)malloc(snaplen);
-                       if (abuf == NULL)
-                               error("ip_print: malloc");
-               }
-               memcpy((char *)abuf, (char *)ip, min(length, snaplen));
-               snapend += abuf - (u_char *)ip;
-               packetp = abuf;
-               ip = (struct ip *)abuf;
-               /* We really want libpcap to give us aligned packets */
-               if (!didwarn) {
-                       warning("compensating for unaligned libpcap packets");
-                       ++didwarn;
-               }
-       }
-#endif
-       if ((u_char *)(ip + 1) > snapend) {
-               printf("[|ip]");
-               return;
-       }
-       if (length < sizeof (struct ip)) {
-               (void)printf("truncated-ip %d", length);
-               return;
-       }
-       hlen = IP_HL(ip) * 4;
-       if (hlen < sizeof (struct ip)) {
-               (void)printf("bad-hlen %d", hlen);
-               return;
-       }
+       shouldbe = sum;
+       shouldbe += ntohs(computed_sum);
+       shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);
+       shouldbe = (shouldbe & 0xFFFF) + (shouldbe >> 16);
+       return shouldbe;
+}
 
-       len = ntohs(ip->ip_len);
-       if (length < len)
-               (void)printf("truncated-ip - %d bytes missing!",
-                       len - length);
-       len -= hlen;
-       len0 = len;
+#define IP_RES 0x8000
 
-       /*
-        * If this is fragment zero, hand it to the next higher
-        * level protocol.
-        */
-       off = ntohs(ip->ip_off);
-       if ((off & 0x1fff) == 0) {
-               cp = (const u_char *)ip + hlen;
-               nh = ip->ip_p;
-
-               if (nh != IPPROTO_TCP && nh != IPPROTO_UDP) {
-                       (void)printf("%s > %s: ", ipaddr_string(&ip->ip_src),
-                               ipaddr_string(&ip->ip_dst));
-               }
-again:
-               switch (nh) {
+static struct tok ip_frag_values[] = {
+        { IP_MF,        "+" },
+        { IP_DF,        "DF" },
+       { IP_RES,       "rsvd" }, /* The RFC3514 evil ;-) bit */
+        { 0,            NULL }
+};
 
-#ifndef IPPROTO_AH
-#define IPPROTO_AH     51
-#endif
-               case IPPROTO_AH:
-                       nh = *cp;
-                       advance = ah_print(cp, (const u_char *)ip);
-                       cp += advance;
-                       len -= advance;
-                       goto again;
-
-#ifndef IPPROTO_ESP
-#define IPPROTO_ESP    50
-#endif
-               case IPPROTO_ESP:
-                   {
-                       int enh;
-                       advance = esp_print(cp, (const u_char *)ip, &enh);
-                       cp += advance;
-                       len -= advance;
-                       if (enh < 0)
-                               break;
-                       nh = enh & 0xff;
-                       goto again;
-                   }
+struct ip_print_demux_state {
+       const struct ip *ip;
+       const u_char *cp;
+       u_int   len, off;
+       u_char  nh;
+       int     advance;
+};
 
-#ifndef IPPROTO_IPCOMP
-#define IPPROTO_IPCOMP 108
-#endif
-               case IPPROTO_IPCOMP:
-                   {
-                       int enh;
-                       advance = ipcomp_print(cp, (const u_char *)ip, &enh);
-                       cp += advance;
-                       len -= advance;
-                       if (enh < 0)
-                               break;
-                       nh = enh & 0xff;
-                       goto again;
-                   }
+static void
+ip_print_demux(netdissect_options *ndo,
+              struct ip_print_demux_state *ipds)
+{
+       struct protoent *proto;
 
-               case IPPROTO_TCP:
-                       tcp_print(cp, len, (const u_char *)ip);
-                       break;
+again:
+       switch (ipds->nh) {
 
-               case IPPROTO_UDP:
-                       udp_print(cp, len, (const u_char *)ip);
+       case IPPROTO_AH:
+               ipds->nh = *ipds->cp;
+               ipds->advance = ah_print(ipds->cp);
+               if (ipds->advance <= 0)
                        break;
-
-               case IPPROTO_ICMP:
-                       icmp_print(cp, len, (const u_char *)ip);
+               ipds->cp += ipds->advance;
+               ipds->len -= ipds->advance;
+               goto again;
+
+       case IPPROTO_ESP:
+       {
+               int enh, padlen;
+               ipds->advance = esp_print(ndo, ipds->cp, ipds->len,
+                                   (const u_char *)ipds->ip,
+                                   &enh, &padlen);
+               if (ipds->advance <= 0)
                        break;
-
-#ifndef IPPROTO_IGRP
-#define IPPROTO_IGRP 9
-#endif
-               case IPPROTO_IGRP:
-                       igrp_print(cp, len, (const u_char *)ip);
+               ipds->cp += ipds->advance;
+               ipds->len -= ipds->advance + padlen;
+               ipds->nh = enh & 0xff;
+               goto again;
+       }
+       
+       case IPPROTO_IPCOMP:
+       {
+               int enh;
+               ipds->advance = ipcomp_print(ipds->cp, &enh);
+               if (ipds->advance <= 0)
                        break;
+               ipds->cp += ipds->advance;
+               ipds->len -= ipds->advance;
+               ipds->nh = enh & 0xff;
+               goto again;
+       }
 
-               case IPPROTO_ND:
-#if 0
-                       (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
-                               ipaddr_string(&ip->ip_dst));
-#endif
-                       (void)printf(" nd %d", len);
-                       break;
+       case IPPROTO_SCTP:
+               sctp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len);
+               break;
 
-               case IPPROTO_EGP:
-                       egp_print(cp, len, (const u_char *)ip);
-                       break;
+       case IPPROTO_DCCP:
+               dccp_print(ipds->cp, (const u_char *)ipds->ip, ipds->len);
+               break;
+               
+       case IPPROTO_TCP:
+               /* pass on the MF bit plus the offset to detect fragments */
+               tcp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
+                         ipds->off & (IP_MF|IP_OFFMASK));
+               break;
+               
+       case IPPROTO_UDP:
+               /* pass on the MF bit plus the offset to detect fragments */
+               udp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
+                         ipds->off & (IP_MF|IP_OFFMASK));
+               break;
+               
+       case IPPROTO_ICMP:
+               /* pass on the MF bit plus the offset to detect fragments */
+               icmp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip,
+                          ipds->off & (IP_MF|IP_OFFMASK));
+               break;
+               
+       case IPPROTO_PIGP:
+               /*
+                * XXX - the current IANA protocol number assignments
+                * page lists 9 as "any private interior gateway
+                * (used by Cisco for their IGRP)" and 88 as
+                * "EIGRP" from Cisco.
+                *
+                * Recent BSD <netinet/in.h> headers define
+                * IP_PROTO_PIGP as 9 and IP_PROTO_IGRP as 88.
+                * We define IP_PROTO_PIGP as 9 and
+                * IP_PROTO_EIGRP as 88; those names better
+                * match was the current protocol number
+                * assignments say.
+                */
+               igrp_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
+               break;
+               
+       case IPPROTO_EIGRP:
+               eigrp_print(ipds->cp, ipds->len);
+               break;
+               
+       case IPPROTO_ND:
+               ND_PRINT((ndo, " nd %d", ipds->len));
+               break;
 
-#ifndef IPPROTO_OSPF
-#define IPPROTO_OSPF 89
-#endif
-               case IPPROTO_OSPF:
-                       ospf_print(cp, len, (const u_char *)ip);
-                       break;
+       case IPPROTO_EGP:
+               egp_print(ipds->cp, ipds->len);
+               break;
 
-#ifndef IPPROTO_IGMP
-#define IPPROTO_IGMP 2
-#endif
-               case IPPROTO_IGMP:
-                       igmp_print(cp, len, (const u_char *)ip);
-                       break;
+       case IPPROTO_OSPF:
+               ospf_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
+               break;
 
-               case 4:
-                       /* DVMRP multicast tunnel (ip-in-ip encapsulation) */
-#if 0
-                       if (vflag)
-                               (void)printf("%s > %s: ",
-                                            ipaddr_string(&ip->ip_src),
-                                            ipaddr_string(&ip->ip_dst));
-#endif
-                       ip_print(cp, len);
-                       if (! vflag) {
-                               printf(" (ipip)");
-                               return;
-                       }
-                       break;
+       case IPPROTO_IGMP:
+               igmp_print(ipds->cp, ipds->len);
+               break;
 
+       case IPPROTO_IPV4:
+               /* DVMRP multicast tunnel (ip-in-ip encapsulation) */
+               ip_print(gndo, ipds->cp, ipds->len);
+               if (! vflag) {
+                       ND_PRINT((ndo, " (ipip-proto-4)"));
+                       return;
+               }
+               break;
+               
 #ifdef INET6
-#ifndef IP6PROTO_ENCAP
-#define IP6PROTO_ENCAP 41
-#endif
-               case IP6PROTO_ENCAP:
-                       /* ip6-in-ip encapsulation */
-#if 0
-                       if (vflag)
-                               (void)printf("%s > %s: ",
-                                            ipaddr_string(&ip->ip_src),
-                                            ipaddr_string(&ip->ip_dst));
-#endif
-                       ip6_print(cp, len);
-                       if (! vflag) {
-                               printf(" (encap)");
-                               return;
-                       }
-                       break;
+       case IPPROTO_IPV6:
+               /* ip6-in-ip encapsulation */
+               ip6_print(ipds->cp, ipds->len);
+               break;
 #endif /*INET6*/
 
+       case IPPROTO_RSVP:
+               rsvp_print(ipds->cp, ipds->len);
+               break;
 
-#ifndef IPPROTO_GRE
-#define IPPROTO_GRE 47
-#endif
-               case IPPROTO_GRE:
-                       if (vflag)
-                               (void)printf("gre %s > %s: ",
-                                            ipaddr_string(&ip->ip_src),
-                                            ipaddr_string(&ip->ip_dst));
-                       /* do it */
-                       gre_print(cp, len);
-                       if (! vflag) {
-                               printf(" (gre encap)");
-                               return;
-                       }
-                       break;
+       case IPPROTO_GRE:
+               /* do it */
+               gre_print(ipds->cp, ipds->len);
+               break;
 
-#ifndef IPPROTO_MOBILE
-#define IPPROTO_MOBILE 55
-#endif
-               case IPPROTO_MOBILE:
-                       if (vflag)
-                               (void)printf("mobile %s > %s: ",
-                                            ipaddr_string(&ip->ip_src),
-                                            ipaddr_string(&ip->ip_dst));
-                       mobile_print(cp, len);
-                       if (! vflag) {
-                               printf(" (mobile encap)");
-                               return;
-                       }
-                       break;
+       case IPPROTO_MOBILE:
+               mobile_print(ipds->cp, ipds->len);
+               break;
 
-#ifndef IPPROTO_PIM
-#define IPPROTO_PIM    103
-#endif
-               case IPPROTO_PIM:
-                       pim_print(cp, len);
-                       break;
+       case IPPROTO_PIM:
+               pim_print(ipds->cp,  ipds->len,
+                         in_cksum((const u_short*)ipds->cp, ipds->len, 0));
+               break;
 
-#ifndef IPPROTO_VRRP
-#define IPPROTO_VRRP   112
-#endif
-               case IPPROTO_VRRP:
-                       vrrp_print(cp, len, ip->ip_ttl);
-                       break;
+       case IPPROTO_VRRP:
+               vrrp_print(ipds->cp, ipds->len, ipds->ip->ip_ttl);
+               break;
 
-               default:
-#if 0
-                       (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
-                               ipaddr_string(&ip->ip_dst));
-#endif
-                       (void)printf(" ip-proto-%d %d", nh, len);
-                       break;
-               }
+       case IPPROTO_PGM:
+               pgm_print(ipds->cp, ipds->len, (const u_char *)ipds->ip);
+               break;
+
+       default:
+               if ((proto = getprotobynumber(ipds->nh)) != NULL)
+                       ND_PRINT((ndo, " %s", proto->p_name));
+               else
+                       ND_PRINT((ndo, " ip-proto-%d", ipds->nh));
+               ND_PRINT((ndo, " %d", ipds->len));
+               break;
        }
+}
+              
+void
+ip_print_inner(netdissect_options *ndo,
+              const u_char *bp,
+              u_int length, u_int nh,
+              const u_char *bp2)
+{
+       struct ip_print_demux_state  ipd;
 
-       /* Ultra quiet now means that all this stuff should be suppressed */
-       /* res 3-Nov-98 */
-       if (qflag > 1) return;
+       ipd.ip = (const struct ip *)bp2;
+       ipd.cp = bp;
+       ipd.len  = length;
+       ipd.off  = 0;
+       ipd.nh   = nh;
+       ipd.advance = 0;
 
+       ip_print_demux(ndo, &ipd);
+}
 
-       /*
-        * for fragmented datagrams, print id:size@offset.  On all
-        * but the last stick a "+".  For unfragmented datagrams, note
-        * the don't fragment flag.
-        */
-       len = len0;     /* get the original length */
-       if (off & 0x3fff) {
-               /*
-                * if this isn't the first frag, we're missing the
-                * next level protocol header.  print the ip addr.
-                */
-               if (off & 0x1fff)
-                       (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
-                                     ipaddr_string(&ip->ip_dst));
-#ifndef IP_MF
-#define IP_MF 0x2000
-#endif /* IP_MF */
-#ifndef IP_DF
-#define IP_DF 0x4000
-#endif /* IP_DF */
-               (void)printf(" (frag %d:%u@%d%s)", ntohs(ip->ip_id), len,
-                       (off & 0x1fff) * 8,
-                       (off & IP_MF)? "+" : "");
-
-       } else if (off & IP_DF)
-               (void)printf(" (DF)");
-
-       if (ip->ip_tos) {
-               (void)printf(" [tos 0x%x", (int)ip->ip_tos);
-               /* ECN bits */
-               if (ip->ip_tos&0x02) {
-                       (void)printf(",ECT");
-                       if (ip->ip_tos&0x01)
-                               (void)printf(",CE");
-               }
-               (void)printf("] ");
+
+/*
+ * print an IP datagram.
+ */
+void
+ip_print(netdissect_options *ndo,
+        const u_char *bp,
+        u_int length)
+{
+       struct ip_print_demux_state  ipd;
+       struct ip_print_demux_state *ipds=&ipd;
+       const u_char *ipend;
+       u_int hlen;
+       u_int16_t sum, ip_sum;
+       struct protoent *proto;
+
+       ipds->ip = (const struct ip *)bp;
+       if (IP_V(ipds->ip) != 4) { /* print version if != 4 */
+           printf("IP%u ", IP_V(ipds->ip));
+           if (IP_V(ipds->ip) == 6)
+               printf(", wrong link-layer encapsulation");
        }
+        else if (!eflag)
+           printf("IP ");
 
-       if (ip->ip_ttl <= 1)
-               (void)printf(" [ttl %d]", (int)ip->ip_ttl);
+       if ((u_char *)(ipds->ip + 1) > snapend) {
+               printf("[|ip]");
+               return;
+       }
+       if (length < sizeof (struct ip)) {
+               (void)printf("truncated-ip %u", length);
+               return;
+       }
+       hlen = IP_HL(ipds->ip) * 4;
+       if (hlen < sizeof (struct ip)) {
+               (void)printf("bad-hlen %u", hlen);
+               return;
+       }
 
-       if (vflag) {
-               int sum;
-               char *sep = "";
+       ipds->len = EXTRACT_16BITS(&ipds->ip->ip_len);
+       if (length < ipds->len)
+               (void)printf("truncated-ip - %u bytes missing! ",
+                       ipds->len - length);
+       if (ipds->len < hlen) {
+#ifdef GUESS_TSO
+            if (ipds->len) {
+                (void)printf("bad-len %u", ipds->len);
+                return;
+            }
+            else {
+                /* we guess that it is a TSO send */
+                ipds->len = length;
+            }
+#else
+            (void)printf("bad-len %u", ipds->len);
+            return;
+#endif /* GUESS_TSO */
+       }
 
-               printf(" (");
-               if (ip->ip_ttl > 1) {
-                       (void)printf("%sttl %d", sep, (int)ip->ip_ttl);
-                       sep = ", ";
-               }
-               if ((off & 0x3fff) == 0) {
-                       (void)printf("%sid %d", sep, (int)ntohs(ip->ip_id));
-                       sep = ", ";
-               }
-               (void)printf("%slen %d", sep, (int)ntohs(ip->ip_len));
-               sep = ", ";
-               if ((u_char *)ip + hlen <= snapend) {
-                       sum = in_cksum((const u_short *)ip, hlen, 0);
-                       if (sum != 0) {
-                               (void)printf("%sbad cksum %x!", sep,
-                                            ntohs(ip->ip_sum));
-                               sep = ", ";
-                       }
+       /*
+        * Cut off the snapshot length to the end of the IP payload.
+        */
+       ipend = bp + ipds->len;
+       if (ipend < snapend)
+               snapend = ipend;
+
+       ipds->len -= hlen;
+
+       ipds->off = EXTRACT_16BITS(&ipds->ip->ip_off);
+
+        if (vflag) {
+            (void)printf("(tos 0x%x", (int)ipds->ip->ip_tos);
+            /* ECN bits */
+            if (ipds->ip->ip_tos & 0x03) {
+                switch (ipds->ip->ip_tos & 0x03) {
+                case 1:
+                    (void)printf(",ECT(1)");
+                    break;
+                case 2:
+                    (void)printf(",ECT(0)");
+                    break;
+                case 3:
+                    (void)printf(",CE");
+                }
+            }
+
+            if (ipds->ip->ip_ttl >= 1)
+                (void)printf(", ttl %u", ipds->ip->ip_ttl);    
+
+           /*
+            * for the firewall guys, print id, offset.
+             * On all but the last stick a "+" in the flags portion.
+            * For unfragmented datagrams, note the don't fragment flag.
+            */
+
+           (void)printf(", id %u, offset %u, flags [%s], proto %s (%u)",
+                         EXTRACT_16BITS(&ipds->ip->ip_id),
+                         (ipds->off & 0x1fff) * 8,
+                         bittok2str(ip_frag_values, "none", ipds->off&0xe000),
+                         tok2str(ipproto_values,"unknown",ipds->ip->ip_p),
+                         ipds->ip->ip_p);
+
+            (void)printf(", length %u", EXTRACT_16BITS(&ipds->ip->ip_len));
+
+            if ((hlen - sizeof(struct ip)) > 0) {
+                printf(", options (");
+                ip_optprint((u_char *)(ipds->ip + 1), hlen - sizeof(struct ip));
+                printf(")");
+            }
+
+           if (!Kflag && (u_char *)ipds->ip + hlen <= snapend) {
+               sum = in_cksum((const u_short *)ipds->ip, hlen, 0);
+               if (sum != 0) {
+                   ip_sum = EXTRACT_16BITS(&ipds->ip->ip_sum);
+                   (void)printf(", bad cksum %x (->%x)!", ip_sum,
+                            in_cksum_shouldbe(ip_sum, sum));
                }
-               if ((hlen -= sizeof(struct ip)) > 0) {
-                       (void)printf("%soptlen=%d", sep, hlen);
-                       ip_optprint((u_char *)(ip + 1), hlen);
+           }
+
+            printf(")\n    ");
+       }
+
+       /*
+        * If this is fragment zero, hand it to the next higher
+        * level protocol.
+        */
+       if ((ipds->off & 0x1fff) == 0) {
+               ipds->cp = (const u_char *)ipds->ip + hlen;
+               ipds->nh = ipds->ip->ip_p;
+
+               if (ipds->nh != IPPROTO_TCP && ipds->nh != IPPROTO_UDP &&
+                   ipds->nh != IPPROTO_SCTP && ipds->nh != IPPROTO_DCCP) {
+                       (void)printf("%s > %s: ",
+                                    ipaddr_string(&ipds->ip->ip_src),
+                                    ipaddr_string(&ipds->ip->ip_dst));
                }
-               printf(")");
+               ip_print_demux(ndo, ipds);
+       } else {
+           /* Ultra quiet now means that all this stuff should be suppressed */
+           if (qflag > 1) return;
+
+           /*
+            * if this isn't the first frag, we're missing the
+            * next level protocol header.  print the ip addr
+            * and the protocol.
+            */
+           if (ipds->off & 0x1fff) {
+               (void)printf("%s > %s:", ipaddr_string(&ipds->ip->ip_src),
+                            ipaddr_string(&ipds->ip->ip_dst));
+               if ((proto = getprotobynumber(ipds->ip->ip_p)) != NULL)
+                   (void)printf(" %s", proto->p_name);
+               else
+                   (void)printf(" ip-proto-%d", ipds->ip->ip_p);
+           } 
        }
 }
 
@@ -738,15 +718,24 @@ ipN_print(register const u_char *bp, register u_int length)
        memcpy (&hdr, (char *)ip, 4);
        switch (IP_V(&hdr)) {
        case 4:
-           ip_print (bp, length);
-           return;
+               ip_print (gndo, bp, length);
+               return;
 #ifdef INET6
        case 6:
-           ip6_print (bp, length);
-           return;
+               ip6_print (bp, length);
+               return;
 #endif
        default:
-           (void)printf("unknown ip %d", IP_V(&hdr));
-           return;
+               (void)printf("unknown ip %d", IP_V(&hdr));
+               return;
        }
 }
+
+/*
+ * Local Variables:
+ * c-style: whitesmith
+ * c-basic-offset: 8
+ * End:
+ */
+
+