]> The Tcpdump Group git mirrors - tcpdump/blobdiff - print-ip6.c
Regenerate config files.
[tcpdump] / print-ip6.c
index 91da17ec4d5a492fd229e704f18d66199f76c6f6..9f590f2af4e1a8763a31b64e2330f7d57868d801 100644 (file)
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  */
 
+/* \summary: IPv6 printer */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#ifdef INET6
-
-#include <tcpdump-stdinc.h>
+#include <netdissect-stdinc.h>
 
-#include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 
 #include "netdissect.h"
-#include "interface.h"
 #include "addrtoname.h"
 #include "extract.h"
 
 #include "ip6.h"
 #include "ipproto.h"
 
+/*
+ * If routing headers are presend and valid, set dst to the final destination.
+ * Otherwise, set it to the IPv6 destination.
+ *
+ * This is used for UDP and TCP pseudo-header in the checksum
+ * calculation.
+ */
+static void
+ip6_finddst(netdissect_options *ndo, struct in6_addr *dst,
+            const struct ip6_hdr *ip6)
+{
+       const u_char *cp;
+       int advance;
+       u_int nh;
+       const struct in6_addr *dst_addr;
+       const struct ip6_rthdr *dp;
+       const struct ip6_rthdr0 *dp0;
+       const struct in6_addr *addr;
+       int i, len;
+
+       cp = (const u_char *)ip6;
+       advance = sizeof(struct ip6_hdr);
+       nh = ip6->ip6_nxt;
+       dst_addr = &ip6->ip6_dst;
+
+       while (cp < ndo->ndo_snapend) {
+               cp += advance;
+
+               switch (nh) {
+
+               case IPPROTO_HOPOPTS:
+               case IPPROTO_DSTOPTS:
+               case IPPROTO_MOBILITY_OLD:
+               case IPPROTO_MOBILITY:
+                       /*
+                        * These have a header length byte, following
+                        * the next header byte, giving the length of
+                        * the header, in units of 8 octets, excluding
+                        * the first 8 octets.
+                        */
+                       ND_TCHECK2(*cp, 2);
+                       advance = (int)((*(cp + 1) + 1) << 3);
+                       nh = *cp;
+                       break;
+
+               case IPPROTO_FRAGMENT:
+                       /*
+                        * The byte following the next header byte is
+                        * marked as reserved, and the header is always
+                        * the same size.
+                        */
+                       ND_TCHECK2(*cp, 1);
+                       advance = sizeof(struct ip6_frag);
+                       nh = *cp;
+                       break;
+
+               case IPPROTO_ROUTING:
+                       /*
+                        * OK, we found it.
+                        */
+                       dp = (const struct ip6_rthdr *)cp;
+                       ND_TCHECK(*dp);
+                       len = dp->ip6r_len;
+                       switch (dp->ip6r_type) {
+
+                       case IPV6_RTHDR_TYPE_0:
+                       case IPV6_RTHDR_TYPE_2:         /* Mobile IPv6 ID-20 */
+                               dp0 = (const struct ip6_rthdr0 *)dp;
+                               if (len % 2 == 1)
+                                       goto trunc;
+                               len >>= 1;
+                               addr = &dp0->ip6r0_addr[0];
+                               for (i = 0; i < len; i++) {
+                                       if ((const u_char *)(addr + 1) > ndo->ndo_snapend)
+                                               goto trunc;
+
+                                       dst_addr = addr;
+                                       addr++;
+                               }
+                               break;
+
+                       default:
+                               break;
+                       }
+
+                       /*
+                        * Only one routing header to a customer.
+                        */
+                       goto done;
+
+               case IPPROTO_AH:
+               case IPPROTO_ESP:
+               case IPPROTO_IPCOMP:
+               default:
+                       /*
+                        * AH and ESP are, in the RFCs that describe them,
+                        * described as being "viewed as an end-to-end
+                        * payload" "in the IPv6 context, so that they
+                        * "should appear after hop-by-hop, routing, and
+                        * fragmentation extension headers".  We assume
+                        * that's the case, and stop as soon as we see
+                        * one.  (We can't handle an ESP header in
+                        * the general case anyway, as its length depends
+                        * on the encryption algorithm.)
+                        *
+                        * IPComp is also "viewed as an end-to-end
+                        * payload" "in the IPv6 context".
+                        *
+                        * All other protocols are assumed to be the final
+                        * protocol.
+                        */
+                       goto done;
+               }
+       }
+
+done:
+trunc:
+       UNALIGNED_MEMCPY(dst, dst_addr, sizeof(struct in6_addr));
+}
+
 /*
  * Compute a V6-style checksum by building a pseudoheader.
  */
 int
-nextproto6_cksum(const struct ip6_hdr *ip6, const u_int8_t *data,
+nextproto6_cksum(netdissect_options *ndo,
+                 const struct ip6_hdr *ip6, const uint8_t *data,
                 u_int len, u_int covlen, u_int next_proto)
 {
         struct {
                 struct in6_addr ph_src;
                 struct in6_addr ph_dst;
-                u_int32_t       ph_len;
-                u_int8_t        ph_zero[3];
-                u_int8_t        ph_nxt;
+                uint32_t       ph_len;
+                uint8_t        ph_zero[3];
+                uint8_t        ph_nxt;
         } ph;
         struct cksum_vec vec[2];
 
         /* pseudo-header */
         memset(&ph, 0, sizeof(ph));
         UNALIGNED_MEMCPY(&ph.ph_src, &ip6->ip6_src, sizeof (struct in6_addr));
-        UNALIGNED_MEMCPY(&ph.ph_dst, &ip6->ip6_dst, sizeof (struct in6_addr));
+        switch (ip6->ip6_nxt) {
+
+        case IPPROTO_HOPOPTS:
+        case IPPROTO_DSTOPTS:
+        case IPPROTO_MOBILITY_OLD:
+        case IPPROTO_MOBILITY:
+        case IPPROTO_FRAGMENT:
+        case IPPROTO_ROUTING:
+                /*
+                 * The next header is either a routing header or a header
+                 * after which there might be a routing header, so scan
+                 * for a routing header.
+                 */
+                ip6_finddst(ndo, &ph.ph_dst, ip6);
+                break;
+
+        default:
+                UNALIGNED_MEMCPY(&ph.ph_dst, &ip6->ip6_dst, sizeof (struct in6_addr));
+                break;
+        }
         ph.ph_len = htonl(len);
         ph.ph_nxt = next_proto;
 
-        vec[0].ptr = (const u_int8_t *)(void *)&ph;
+        vec[0].ptr = (const uint8_t *)(void *)&ph;
         vec[0].len = sizeof(ph);
         vec[1].ptr = data;
         vec[1].len = covlen;
@@ -88,9 +225,9 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
 
        ip6 = (const struct ip6_hdr *)bp;
 
-       TCHECK(*ip6);
+       ND_TCHECK(*ip6);
        if (length < sizeof (struct ip6_hdr)) {
-               (void)ND_PRINT((ndo, "truncated-ip6 %u", length));
+               ND_PRINT((ndo, "truncated-ip6 %u", length));
                return;
        }
 
@@ -105,7 +242,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
        payload_len = EXTRACT_16BITS(&ip6->ip6_plen);
        len = payload_len + sizeof(struct ip6_hdr);
        if (length < len)
-               (void)ND_PRINT((ndo, "truncated-ip6 - %u bytes missing!",
+               ND_PRINT((ndo, "truncated-ip6 - %u bytes missing!",
                        len - length));
 
         if (ndo->ndo_vflag) {
@@ -114,18 +251,18 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
 #if 0
             /* rfc1883 */
             if (flow & 0x0f000000)
-               (void)ND_PRINT((ndo, "pri 0x%02x, ", (flow & 0x0f000000) >> 24));
+               ND_PRINT((ndo, "pri 0x%02x, ", (flow & 0x0f000000) >> 24));
             if (flow & 0x00ffffff)
-               (void)ND_PRINT((ndo, "flowlabel 0x%06x, ", flow & 0x00ffffff));
+               ND_PRINT((ndo, "flowlabel 0x%06x, ", flow & 0x00ffffff));
 #else
             /* RFC 2460 */
             if (flow & 0x0ff00000)
-               (void)ND_PRINT((ndo, "class 0x%02x, ", (flow & 0x0ff00000) >> 20));
+               ND_PRINT((ndo, "class 0x%02x, ", (flow & 0x0ff00000) >> 20));
             if (flow & 0x000fffff)
-               (void)ND_PRINT((ndo, "flowlabel 0x%05x, ", flow & 0x000fffff));
+               ND_PRINT((ndo, "flowlabel 0x%05x, ", flow & 0x000fffff));
 #endif
 
-            (void)ND_PRINT((ndo, "hlim %u, next-header %s (%u) payload length: %u) ",
+            ND_PRINT((ndo, "hlim %u, next-header %s (%u) payload length: %u) ",
                          ip6->ip6_hlim,
                          tok2str(ipproto_values,"unknown",ip6->ip6_nxt),
                          ip6->ip6_nxt,
@@ -149,22 +286,26 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
                if (cp == (const u_char *)(ip6 + 1) &&
                    nh != IPPROTO_TCP && nh != IPPROTO_UDP &&
                    nh != IPPROTO_DCCP && nh != IPPROTO_SCTP) {
-                       (void)ND_PRINT((ndo, "%s > %s: ", ip6addr_string(&ip6->ip6_src),
-                                    ip6addr_string(&ip6->ip6_dst)));
+                       ND_PRINT((ndo, "%s > %s: ", ip6addr_string(ndo, &ip6->ip6_src),
+                                    ip6addr_string(ndo, &ip6->ip6_dst)));
                }
 
                switch (nh) {
                case IPPROTO_HOPOPTS:
-                       advance = hbhopt_print(cp);
+                       advance = hbhopt_print(ndo, cp);
+                       if (advance < 0)
+                               return;
                        nh = *cp;
                        break;
                case IPPROTO_DSTOPTS:
-                       advance = dstopt_print(cp);
+                       advance = dstopt_print(ndo, cp);
+                       if (advance < 0)
+                               return;
                        nh = *cp;
                        break;
                case IPPROTO_FRAGMENT:
                        advance = frag6_print(ndo, cp, (const u_char *)ip6);
-                       if (ndo->ndo_snapend <= cp + advance)
+                       if (advance < 0 || ndo->ndo_snapend <= cp + advance)
                                return;
                        nh = *cp;
                        fragmented = 1;
@@ -173,39 +314,37 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
                case IPPROTO_MOBILITY_OLD:
                case IPPROTO_MOBILITY:
                        /*
-                        * XXX - we don't use "advance"; the current
-                        * "Mobility Support in IPv6" draft
-                        * (draft-ietf-mobileip-ipv6-24) says that
+                        * XXX - we don't use "advance"; RFC 3775 says that
                         * the next header field in a mobility header
                         * should be IPPROTO_NONE, but speaks of
                         * the possiblity of a future extension in
                         * which payload can be piggybacked atop a
                         * mobility header.
                         */
-                       advance = mobility_print(cp, (const u_char *)ip6);
+                       advance = mobility_print(ndo, cp, (const u_char *)ip6);
                        nh = *cp;
                        return;
                case IPPROTO_ROUTING:
-                       advance = rt6_print(cp, (const u_char *)ip6);
+                       advance = rt6_print(ndo, cp, (const u_char *)ip6);
                        nh = *cp;
                        break;
                case IPPROTO_SCTP:
-                       sctp_print(cp, (const u_char *)ip6, len);
+                       sctp_print(ndo, cp, (const u_char *)ip6, len);
                        return;
                case IPPROTO_DCCP:
-                       dccp_print(cp, (const u_char *)ip6, len);
+                       dccp_print(ndo, cp, (const u_char *)ip6, len);
                        return;
                case IPPROTO_TCP:
-                       tcp_print(cp, len, (const u_char *)ip6, fragmented);
+                       tcp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
                        return;
                case IPPROTO_UDP:
-                       udp_print(cp, len, (const u_char *)ip6, fragmented);
+                       udp_print(ndo, cp, len, (const u_char *)ip6, fragmented);
                        return;
                case IPPROTO_ICMPV6:
                        icmp6_print(ndo, cp, len, (const u_char *)ip6, fragmented);
                        return;
                case IPPROTO_AH:
-                       advance = ah_print(gndo, cp);
+                       advance = ah_print(ndo, cp);
                        nh = *cp;
                        break;
                case IPPROTO_ESP:
@@ -218,19 +357,23 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
                    }
                case IPPROTO_IPCOMP:
                    {
-                       int enh;
-                       advance = ipcomp_print(ndo, cp, &enh);
-                       nh = enh & 0xff;
+                       ipcomp_print(ndo, cp);
+                       /*
+                        * Either this has decompressed the payload and
+                        * printed it, in which case there's nothing more
+                        * to do, or it hasn't, in which case there's
+                        * nothing more to do.
+                        */
+                       advance = -1;
                        break;
                    }
 
                case IPPROTO_PIM:
-                       pim_print(cp, len, nextproto6_cksum(ip6, cp, len, len,
-                                                           IPPROTO_PIM));
+                       pim_print(ndo, cp, len, (const u_char *)ip6);
                        return;
 
                case IPPROTO_OSPF:
-                       ospf6_print(cp, len);
+                       ospf6_print(ndo, cp, len);
                        return;
 
                case IPPROTO_IPV6:
@@ -242,7 +385,7 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
                        return;
 
                 case IPPROTO_PGM:
-                        pgm_print(cp, len, (const u_char *)ip6);
+                        pgm_print(ndo, cp, len, (const u_char *)ip6);
                         return;
 
                case IPPROTO_GRE:
@@ -250,22 +393,20 @@ ip6_print(netdissect_options *ndo, const u_char *bp, u_int length)
                        return;
 
                case IPPROTO_RSVP:
-                       rsvp_print(cp, len);
+                       rsvp_print(ndo, cp, len);
                        return;
 
                case IPPROTO_NONE:
-                       (void)ND_PRINT((ndo, "no next header"));
+                       ND_PRINT((ndo, "no next header"));
                        return;
 
                default:
-                       (void)ND_PRINT((ndo, "ip-proto-%d %d", nh, len));
+                       ND_PRINT((ndo, "ip-proto-%d %d", nh, len));
                        return;
                }
        }
 
        return;
 trunc:
-       (void)ND_PRINT((ndo, "[|ip6]"));
+       ND_PRINT((ndo, "[|ip6]"));
 }
-
-#endif /* INET6 */