1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 */ 21 22 #include <sys/cdefs.h> 23 #ifndef lint 24 #if 0 25 static const char rcsid[] _U_ = 26 "@(#) Header: /tcpdump/master/tcpdump/print-ip6.c,v 1.52 2007-09-21 07:05:33 hannes Exp"; 27 #else 28 __RCSID("$NetBSD: print-ip6.c,v 1.2 2010/12/05 05:11:30 christos Exp $"); 29 #endif 30 #endif 31 32 #ifdef HAVE_CONFIG_H 33 #include "config.h" 34 #endif 35 36 #ifdef INET6 37 38 #include <tcpdump-stdinc.h> 39 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 44 #include "netdissect.h" 45 #include "interface.h" 46 #include "addrtoname.h" 47 #include "extract.h" 48 49 #include "ip6.h" 50 #include "ipproto.h" 51 52 /* 53 * Compute a V6-style checksum by building a pseudoheader. 54 */ 55 int 56 nextproto6_cksum(const struct ip6_hdr *ip6, const u_short *data, 57 u_int len, u_int next_proto) 58 { 59 size_t i; 60 u_int32_t sum = 0; 61 union ip6_pseudo_hdr phu; 62 63 /* pseudo-header */ 64 memset(&phu, 0, sizeof(phu)); 65 phu.ph.ph_src = ip6->ip6_src; 66 phu.ph.ph_dst = ip6->ip6_dst; 67 phu.ph.ph_len = htonl(len); 68 phu.ph.ph_nxt = next_proto; 69 70 for (i = 0; i < sizeof(phu.pa) / sizeof(phu.pa[0]); i++) { 71 sum += phu.pa[i]; 72 } 73 74 return in_cksum(data, len, sum); 75 } 76 77 /* 78 * print an IP6 datagram. 79 */ 80 void 81 ip6_print(register const u_char *bp, register u_int length) 82 { 83 register const struct ip6_hdr *ip6; 84 register int advance; 85 u_int len; 86 const u_char *ipend; 87 register const u_char *cp; 88 register u_int payload_len; 89 int nh; 90 int fragmented = 0; 91 u_int flow; 92 93 ip6 = (const struct ip6_hdr *)bp; 94 95 TCHECK(*ip6); 96 if (length < sizeof (struct ip6_hdr)) { 97 (void)printf("truncated-ip6 %u", length); 98 return; 99 } 100 101 if (!eflag) 102 printf("IP6 "); 103 104 payload_len = EXTRACT_16BITS(&ip6->ip6_plen); 105 len = payload_len + sizeof(struct ip6_hdr); 106 if (length < len) 107 (void)printf("truncated-ip6 - %u bytes missing!", 108 len - length); 109 110 if (vflag) { 111 flow = EXTRACT_32BITS(&ip6->ip6_flow); 112 printf("("); 113 #if 0 114 /* rfc1883 */ 115 if (flow & 0x0f000000) 116 (void)printf("pri 0x%02x, ", (flow & 0x0f000000) >> 24); 117 if (flow & 0x00ffffff) 118 (void)printf("flowlabel 0x%06x, ", flow & 0x00ffffff); 119 #else 120 /* RFC 2460 */ 121 if (flow & 0x0ff00000) 122 (void)printf("class 0x%02x, ", (flow & 0x0ff00000) >> 20); 123 if (flow & 0x000fffff) 124 (void)printf("flowlabel 0x%05x, ", flow & 0x000fffff); 125 #endif 126 127 (void)printf("hlim %u, next-header %s (%u) payload length: %u) ", 128 ip6->ip6_hlim, 129 tok2str(ipproto_values,"unknown",ip6->ip6_nxt), 130 ip6->ip6_nxt, 131 payload_len); 132 } 133 134 /* 135 * Cut off the snapshot length to the end of the IP payload. 136 */ 137 ipend = bp + len; 138 if (ipend < snapend) 139 snapend = ipend; 140 141 cp = (const u_char *)ip6; 142 advance = sizeof(struct ip6_hdr); 143 nh = ip6->ip6_nxt; 144 while (cp < snapend && advance > 0) { 145 cp += advance; 146 len -= advance; 147 148 if (cp == (const u_char *)(ip6 + 1) && 149 nh != IPPROTO_TCP && nh != IPPROTO_UDP && 150 nh != IPPROTO_DCCP && nh != IPPROTO_SCTP) { 151 (void)printf("%s > %s: ", ip6addr_string(&ip6->ip6_src), 152 ip6addr_string(&ip6->ip6_dst)); 153 } 154 155 switch (nh) { 156 case IPPROTO_HOPOPTS: 157 advance = hbhopt_print(cp); 158 nh = *cp; 159 break; 160 case IPPROTO_DSTOPTS: 161 advance = dstopt_print(cp); 162 nh = *cp; 163 break; 164 case IPPROTO_FRAGMENT: 165 advance = frag6_print(cp, (const u_char *)ip6); 166 if (snapend <= cp + advance) 167 return; 168 nh = *cp; 169 fragmented = 1; 170 break; 171 172 case IPPROTO_MOBILITY_OLD: 173 case IPPROTO_MOBILITY: 174 /* 175 * XXX - we don't use "advance"; the current 176 * "Mobility Support in IPv6" draft 177 * (draft-ietf-mobileip-ipv6-24) says that 178 * the next header field in a mobility header 179 * should be IPPROTO_NONE, but speaks of 180 * the possiblity of a future extension in 181 * which payload can be piggybacked atop a 182 * mobility header. 183 */ 184 advance = mobility_print(cp, (const u_char *)ip6); 185 nh = *cp; 186 return; 187 case IPPROTO_ROUTING: 188 advance = rt6_print(cp, (const u_char *)ip6); 189 nh = *cp; 190 break; 191 case IPPROTO_SCTP: 192 sctp_print(cp, (const u_char *)ip6, len); 193 return; 194 case IPPROTO_DCCP: 195 dccp_print(cp, (const u_char *)ip6, len); 196 return; 197 case IPPROTO_TCP: 198 tcp_print(cp, len, (const u_char *)ip6, fragmented); 199 return; 200 case IPPROTO_UDP: 201 udp_print(cp, len, (const u_char *)ip6, fragmented); 202 return; 203 case IPPROTO_ICMPV6: 204 icmp6_print(gndo, cp, len, (const u_char *)ip6, fragmented); 205 return; 206 case IPPROTO_AH: 207 advance = ah_print(cp); 208 nh = *cp; 209 break; 210 case IPPROTO_ESP: 211 { 212 int enh, padlen; 213 advance = esp_print(gndo, cp, len, (const u_char *)ip6, &enh, &padlen); 214 nh = enh & 0xff; 215 len -= padlen; 216 break; 217 } 218 case IPPROTO_IPCOMP: 219 { 220 int enh; 221 advance = ipcomp_print(cp, &enh); 222 nh = enh & 0xff; 223 break; 224 } 225 226 case IPPROTO_PIM: 227 pim_print(cp, len, nextproto6_cksum(ip6, (u_short *)cp, len, 228 IPPROTO_PIM)); 229 return; 230 231 case IPPROTO_OSPF: 232 ospf6_print(cp, len); 233 return; 234 235 case IPPROTO_IPV6: 236 ip6_print(cp, len); 237 return; 238 239 case IPPROTO_IPV4: 240 ip_print(gndo, cp, len); 241 return; 242 243 case IPPROTO_PGM: 244 pgm_print(cp, len, (const u_char *)ip6); 245 return; 246 247 case IPPROTO_GRE: 248 gre_print(cp, len); 249 return; 250 251 case IPPROTO_RSVP: 252 rsvp_print(cp, len); 253 return; 254 255 case IPPROTO_NONE: 256 (void)printf("no next header"); 257 return; 258 259 default: 260 (void)printf("ip-proto-%d %d", nh, len); 261 return; 262 } 263 } 264 265 return; 266 trunc: 267 (void)printf("[|ip6]"); 268 } 269 270 #endif /* INET6 */ 271