tcpdump.tproj/print-ip.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * "Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.0 (the 'License').  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License."
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996
  26  *      The Regents of the University of California.  All rights reserved.
  27  *
  28  * Redistribution and use in source and binary forms, with or without
  29  * modification, are permitted provided that: (1) source code distributions
  30  * retain the above copyright notice and this paragraph in its entirety, (2)
  31  * distributions including binary code include the above copyright notice and
  32  * this paragraph in its entirety in the documentation or other materials
  33  * provided with the distribution, and (3) all advertising materials mentioning
  34  * features or use of this software display the following acknowledgement:
  35  * ``This product includes software developed by the University of California,
  36  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  37  * the University nor the names of its contributors may be used to endorse
  38  * or promote products derived from this software without specific prior
  39  * written permission.
  40  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  41  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  42  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  43  */
  44
  45 #ifndef lint
  46 static const char rcsid[] =
  47     "@(#) $Header: /cvs/Darwin/Commands/NeXT/network_cmds/tcpdump.tproj/print-ip.c,v 1.1.1.1 1999/05/02 03:58:33 wsanchez Exp $ (LBL)";
  48 #endif
  49
  50 #include <sys/param.h>
  51 #include <sys/time.h>
  52 #include <sys/socket.h>
  53
  54 #include <netinet/in.h>
  55 #include <netinet/in_systm.h>
  56 #include <netinet/ip.h>
  57 #include <netinet/ip_var.h>
  58 #include <netinet/udp.h>
  59 #include <netinet/udp_var.h>
  60 #include <netinet/tcp.h>
  61 #include <netinet/tcpip.h>
  62
  63 #include <stdio.h>
  64 #include <stdlib.h>
  65 #include <string.h>
  66 #include <unistd.h>
  67
  68 #include "addrtoname.h"
  69 #include "interface.h"
  70 #include "extract.h"                    /* must come after interface.h */
  71
  72 /* Compatibility */
  73 #ifndef IPPROTO_ND
  74 #define IPPROTO_ND      77
  75 #endif
  76
  77 #ifndef IN_CLASSD
  78 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
  79 #endif
  80
  81 /* (following from ipmulti/mrouted/prune.h) */
  82
  83 /*
  84  * The packet format for a traceroute request.
  85  */
  86 struct tr_query {
  87         u_int  tr_src;                  /* traceroute source */
  88         u_int  tr_dst;                  /* traceroute destination */
  89         u_int  tr_raddr;                /* traceroute response address */
  90 #ifdef WORDS_BIGENDIAN
  91         struct {
  92                 u_int   ttl : 8;        /* traceroute response ttl */
  93                 u_int   qid : 24;       /* traceroute query id */
  94         } q;
  95 #else
  96         struct {
  97                 u_int   qid : 24;       /* traceroute query id */
  98                 u_int   ttl : 8;        /* traceroute response ttl */
  99         } q;
 100 #endif
 101 };
 102
 103 #define tr_rttl q.ttl
 104 #define tr_qid  q.qid
 105
 106 /*
 107  * Traceroute response format.  A traceroute response has a tr_query at the
 108  * beginning, followed by one tr_resp for each hop taken.
 109  */
 110 struct tr_resp {
 111         u_int tr_qarr;                  /* query arrival time */
 112         u_int tr_inaddr;                /* incoming interface address */
 113         u_int tr_outaddr;               /* outgoing interface address */
 114         u_int tr_rmtaddr;               /* parent address in source tree */
 115         u_int tr_vifin;                 /* input packet count on interface */
 116         u_int tr_vifout;                /* output packet count on interface */
 117         u_int tr_pktcnt;                /* total incoming packets for src-grp */
 118         u_char  tr_rproto;              /* routing proto deployed on router */
 119         u_char  tr_fttl;                /* ttl required to forward on outvif */
 120         u_char  tr_smask;               /* subnet mask for src addr */
 121         u_char  tr_rflags;              /* forwarding error codes */
 122 };
 123
 124 /* defs within mtrace */
 125 #define TR_QUERY 1
 126 #define TR_RESP 2
 127
 128 /* fields for tr_rflags (forwarding error codes) */
 129 #define TR_NO_ERR       0
 130 #define TR_WRONG_IF     1
 131 #define TR_PRUNED       2
 132 #define TR_OPRUNED      3
 133 #define TR_SCOPED       4
 134 #define TR_NO_RTE       5
 135 #define TR_NO_FWD       7
 136 #define TR_NO_SPACE     0x81
 137 #define TR_OLD_ROUTER   0x82
 138
 139 /* fields for tr_rproto (routing protocol) */
 140 #define TR_PROTO_DVMRP  1
 141 #define TR_PROTO_MOSPF  2
 142 #define TR_PROTO_PIM    3
 143 #define TR_PROTO_CBT    4
 144
 145 static void print_mtrace(register const u_char *bp, register u_int len)
 146 {
 147         register struct tr_query *tr = (struct tr_query *)(bp + 8);
 148
 149         printf("mtrace %d: %s to %s reply-to %s", tr->tr_qid,
 150                 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
 151                 ipaddr_string(&tr->tr_raddr));
 152         if (IN_CLASSD(ntohl(tr->tr_raddr)))
 153                 printf(" with-ttl %d", tr->tr_rttl);
 154 }
 155
 156 static void print_mresp(register const u_char *bp, register u_int len)
 157 {
 158         register struct tr_query *tr = (struct tr_query *)(bp + 8);
 159
 160         printf("mresp %d: %s to %s reply-to %s", tr->tr_qid,
 161                 ipaddr_string(&tr->tr_src), ipaddr_string(&tr->tr_dst),
 162                 ipaddr_string(&tr->tr_raddr));
 163         if (IN_CLASSD(ntohl(tr->tr_raddr)))
 164                 printf(" with-ttl %d", tr->tr_rttl);
 165 }
 166
 167 static void
 168 igmp_print(register const u_char *bp, register u_int len,
 169            register const u_char *bp2)
 170 {
 171         register const struct ip *ip;
 172
 173         ip = (const struct ip *)bp2;
 174         (void)printf("%s > %s: ",
 175                 ipaddr_string(&ip->ip_src),
 176                 ipaddr_string(&ip->ip_dst));
 177
 178         TCHECK2(bp[0], 8);
 179         switch (bp[0]) {
 180         case 0x11:
 181                 (void)printf("igmp query");
 182                 if (*(int *)&bp[4])
 183                         (void)printf(" [gaddr %s]", ipaddr_string(&bp[4]));
 184                 if (len != 8)
 185                         (void)printf(" [len %d]", len);
 186                 break;
 187         case 0x12:
 188                 (void)printf("igmp report %s", ipaddr_string(&bp[4]));
 189                 if (len != 8)
 190                         (void)printf(" [len %d]", len);
 191                 break;
 192         case 0x16:
 193                 (void)printf("igmp nreport %s", ipaddr_string(&bp[4]));
 194                 break;
 195         case 0x17:
 196                 (void)printf("igmp leave %s", ipaddr_string(&bp[4]));
 197                 break;
 198         case 0x13:
 199                 (void)printf("igmp dvmrp");
 200                 if (len < 8)
 201                         (void)printf(" [len %d]", len);
 202                 else
 203                         dvmrp_print(bp, len);
 204                 break;
 205         case 0x14:
 206                 (void)printf("igmp pim");
 207                 pim_print(bp, len);
 208                 break;
 209         case 0x1e:
 210                 print_mresp(bp, len);
 211                 break;
 212         case 0x1f:
 213                 print_mtrace(bp, len);
 214                 break;
 215         default:
 216                 (void)printf("igmp-%d", bp[0] & 0xf);
 217                 break;
 218         }
 219         if ((bp[0] >> 4) != 1)
 220                 (void)printf(" [v%d]", bp[0] >> 4);
 221
 222         TCHECK2(bp[0], len);
 223         if (vflag) {
 224                 /* Check the IGMP checksum */
 225                 u_int32_t sum = 0;
 226                 int count;
 227                 const u_short *sp = (u_short *)bp;
 228
 229                 for (count = len / 2; --count >= 0; )
 230                         sum += *sp++;
 231                 if (len & 1)
 232                         sum += ntohs(*(u_char *) sp << 8);
 233                 while (sum >> 16)
 234                         sum = (sum & 0xffff) + (sum >> 16);
 235                 sum = 0xffff & ~sum;
 236                 if (sum != 0)
 237                         printf(" bad igmp cksum %x!", EXTRACT_16BITS(&bp[2]));
 238         }
 239         return;
 240 trunc:
 241         fputs("[|igmp]", stdout);
 242 }
 243
 244 /*
 245  * print the recorded route in an IP RR, LSRR or SSRR option.
 246  */
 247 static void
 248 ip_printroute(const char *type, register const u_char *cp, u_int length)
 249 {
 250         register u_int ptr = cp[2] - 1;
 251         register u_int len;
 252
 253         printf(" %s{", type);
 254         if ((length + 1) & 3)
 255                 printf(" [bad length %d]", length);
 256         if (ptr < 3 || ((ptr + 1) & 3) || ptr > length + 1)
 257                 printf(" [bad ptr %d]", cp[2]);
 258
 259         type = "";
 260         for (len = 3; len < length; len += 4) {
 261                 if (ptr == len)
 262                         type = "#";
 263                 printf("%s%s", type, ipaddr_string(&cp[len]));
 264                 type = " ";
 265         }
 266         printf("%s}", ptr == len? "#" : "");
 267 }
 268
 269 /*
 270  * print IP options.
 271  */
 272 static void
 273 ip_optprint(register const u_char *cp, u_int length)
 274 {
 275         register u_int len;
 276
 277         for (; length > 0; cp += len, length -= len) {
 278                 int tt = *cp;
 279
 280                 len = (tt == IPOPT_NOP || tt == IPOPT_EOL) ? 1 : cp[1];
 281                 if (len <= 0) {
 282                         printf("[|ip op len %d]", len);
 283                         return;
 284                 }
 285                 if (&cp[1] >= snapend || cp + len > snapend) {
 286                         printf("[|ip]");
 287                         return;
 288                 }
 289                 switch (tt) {
 290
 291                 case IPOPT_EOL:
 292                         printf(" EOL");
 293                         if (length > 1)
 294                                 printf("-%d", length - 1);
 295                         return;
 296
 297                 case IPOPT_NOP:
 298                         printf(" NOP");
 299                         break;
 300
 301                 case IPOPT_TS:
 302                         printf(" TS{%d}", len);
 303                         break;
 304
 305                 case IPOPT_SECURITY:
 306                         printf(" SECURITY{%d}", len);
 307                         break;
 308
 309                 case IPOPT_RR:
 310                         printf(" RR{%d}=", len);
 311                         ip_printroute("RR", cp, len);
 312                         break;
 313
 314                 case IPOPT_SSRR:
 315                         ip_printroute("SSRR", cp, len);
 316                         break;
 317
 318                 case IPOPT_LSRR:
 319                         ip_printroute("LSRR", cp, len);
 320                         break;
 321
 322                 default:
 323                         printf(" IPOPT-%d{%d}", cp[0], len);
 324                         break;
 325                 }
 326         }
 327 }
 328
 329 /*
 330  * compute an IP header checksum.
 331  * don't modifiy the packet.
 332  */
 333 static int
 334 in_cksum(const struct ip *ip)
 335 {
 336         register const u_short *sp = (u_short *)ip;
 337         register u_int32_t sum = 0;
 338         register int count;
 339
 340         /*
 341          * No need for endian conversions.
 342          */
 343         for (count = ip->ip_hl * 2; --count >= 0; )
 344                 sum += *sp++;
 345         while (sum > 0xffff)
 346                 sum = (sum & 0xffff) + (sum >> 16);
 347         sum = ~sum & 0xffff;
 348
 349         return (sum);
 350 }
 351
 352 /*
 353  * print an IP datagram.
 354  */
 355 void
 356 ip_print(register const u_char *bp, register u_int length)
 357 {
 358         register const struct ip *ip;
 359         register u_int hlen, len, off;
 360         register const u_char *cp;
 361
 362         ip = (const struct ip *)bp;
 363 #ifdef LBL_ALIGN
 364         /*
 365          * If the IP header is not aligned, copy into abuf.
 366          * This will never happen with BPF.  It does happen raw packet
 367          * dumps from -r.
 368          */
 369         if ((long)ip & 3) {
 370                 static u_char *abuf = NULL;
 371                 static int didwarn = 0;
 372
 373                 if (abuf == NULL) {
 374                         abuf = (u_char *)malloc(snaplen);
 375                         if (abuf == NULL)
 376                                 error("ip_print: malloc");
 377                 }
 378                 memcpy((char *)abuf, (char *)ip, min(length, snaplen));
 379                 snapend += abuf - (u_char *)ip;
 380                 packetp = abuf;
 381                 ip = (struct ip *)abuf;
 382                 /* We really want libpcap to give us aligned packets */
 383                 if (!didwarn) {
 384                         warning("compensating for unaligned libpcap packets");
 385                         ++didwarn;
 386                 }
 387         }
 388 #endif
 389         if ((u_char *)(ip + 1) > snapend) {
 390                 printf("[|ip]");
 391                 return;
 392         }
 393         if (length < sizeof (struct ip)) {
 394                 (void)printf("truncated-ip %d", length);
 395                 return;
 396         }
 397         hlen = ip->ip_hl * 4;
 398
 399         len = ntohs(ip->ip_len);
 400         if (length < len)
 401                 (void)printf("truncated-ip - %d bytes missing!",
 402                         len - length);
 403         len -= hlen;
 404
 405         /*
 406          * If this is fragment zero, hand it to the next higher
 407          * level protocol.
 408          */
 409         off = ntohs(ip->ip_off);
 410         if ((off & 0x1fff) == 0) {
 411                 cp = (const u_char *)ip + hlen;
 412                 switch (ip->ip_p) {
 413
 414                 case IPPROTO_TCP:
 415                         tcp_print(cp, len, (const u_char *)ip);
 416                         break;
 417
 418                 case IPPROTO_UDP:
 419                         udp_print(cp, len, (const u_char *)ip);
 420                         break;
 421
 422                 case IPPROTO_ICMP:
 423                         icmp_print(cp, (const u_char *)ip);
 424                         break;
 425
 426 #ifndef IPPROTO_IGRP
 427 #define IPPROTO_IGRP 9
 428 #endif
 429                 case IPPROTO_IGRP:
 430                         igrp_print(cp, len, (const u_char *)ip);
 431                         break;
 432
 433                 case IPPROTO_ND:
 434                         (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
 435                                 ipaddr_string(&ip->ip_dst));
 436                         (void)printf(" nd %d", len);
 437                         break;
 438
 439                 case IPPROTO_EGP:
 440                         egp_print(cp, len, (const u_char *)ip);
 441                         break;
 442
 443 #ifndef IPPROTO_OSPF
 444 #define IPPROTO_OSPF 89
 445 #endif
 446                 case IPPROTO_OSPF:
 447                         ospf_print(cp, len, (const u_char *)ip);
 448                         break;
 449
 450 #ifndef IPPROTO_IGMP
 451 #define IPPROTO_IGMP 2
 452 #endif
 453                 case IPPROTO_IGMP:
 454                         igmp_print(cp, len, (const u_char *)ip);
 455                         break;
 456
 457 #ifndef IPPROTO_ENCAP
 458 #define IPPROTO_ENCAP 4
 459 #endif
 460                 case IPPROTO_ENCAP:
 461                         /* ip-in-ip encapsulation */
 462                         if (vflag)
 463                                 (void)printf("%s > %s: ",
 464                                              ipaddr_string(&ip->ip_src),
 465                                              ipaddr_string(&ip->ip_dst));
 466                         ip_print(cp, len);
 467                         if (! vflag) {
 468                                 printf(" (encap)");
 469                                 return;
 470                         }
 471                         break;
 472
 473 #ifndef IPPROTO_GRE
 474 #define IPPROTO_GRE 47
 475 #endif
 476                 case IPPROTO_GRE:
 477                         if (vflag)
 478                                 (void)printf("gre %s > %s: ",
 479                                              ipaddr_string(&ip->ip_src),
 480                                              ipaddr_string(&ip->ip_dst));
 481                         /* do it */
 482                         gre_print(cp, len);
 483                         if (! vflag) {
 484                                 printf(" (gre encap)");
 485                                 return;
 486                         }
 487                         break;
 488
 489                 default:
 490                         (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
 491                                 ipaddr_string(&ip->ip_dst));
 492                         (void)printf(" ip-proto-%d %d", ip->ip_p, len);
 493                         break;
 494                 }
 495         }
 496         /*
 497          * for fragmented datagrams, print id:size@offset.  On all
 498          * but the last stick a "+".  For unfragmented datagrams, note
 499          * the don't fragment flag.
 500          */
 501         if (off & 0x3fff) {
 502                 /*
 503                  * if this isn't the first frag, we're missing the
 504                  * next level protocol header.  print the ip addr.
 505                  */
 506                 if (off & 0x1fff)
 507                         (void)printf("%s > %s:", ipaddr_string(&ip->ip_src),
 508                                       ipaddr_string(&ip->ip_dst));
 509                 (void)printf(" (frag %d:%d@%d%s)", ntohs(ip->ip_id), len,
 510                         (off & 0x1fff) * 8,
 511                         (off & IP_MF)? "+" : "");
 512         } else if (off & IP_DF)
 513                 (void)printf(" (DF)");
 514
 515         if (ip->ip_tos)
 516                 (void)printf(" [tos 0x%x]", (int)ip->ip_tos);
 517         if (ip->ip_ttl <= 1)
 518                 (void)printf(" [ttl %d]", (int)ip->ip_ttl);
 519
 520         if (vflag) {
 521                 int sum;
 522                 char *sep = "";
 523
 524                 printf(" (");
 525                 if (ip->ip_ttl > 1) {
 526                         (void)printf("%sttl %d", sep, (int)ip->ip_ttl);
 527                         sep = ", ";
 528                 }
 529                 if ((off & 0x3fff) == 0) {
 530                         (void)printf("%sid %d", sep, (int)ntohs(ip->ip_id));
 531                         sep = ", ";
 532                 }
 533                 if ((u_char *)ip + hlen <= snapend) {
 534                         sum = in_cksum(ip);
 535                         if (sum != 0) {
 536                                 (void)printf("%sbad cksum %x!", sep,
 537                                              ntohs(ip->ip_sum));
 538                                 sep = ", ";
 539                         }
 540                 }
 541                 if ((hlen -= sizeof(struct ip)) > 0) {
 542                         (void)printf("%soptlen=%d", sep, hlen);
 543                         ip_optprint((u_char *)(ip + 1), hlen);
 544                 }
 545                 printf(")");
 546         }
 547 }