/* * Copyright (c) 1987-1990 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that: (1) source code distributions * retain the above copyright notice and this paragraph in its entirety, (2) * distributions including binary code include the above copyright notice and * this paragraph in its entirety in the documentation or other materials * provided with the distribution, and (3) all advertising materials mentioning * features or use of this software display the following acknowledgement: * ``This product includes software developed by the University of California, * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of * the University nor the names of its contributors may be used to endorse * or promote products derived from this software without specific prior * written permission. * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */ #ifndef lint char copyright[] = "@(#) Copyright (c) 1987-1990 The Regents of the University of California.\nAll rights reserved.\n"; static char rcsid[] = "@(#)$Header: tcpdump.c,v 1.68 92/06/02 17:57:41 mccanne Exp $ (LBL)"; #endif /* * tcpdump - monitor tcp/ip traffic on an ethernet. * * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory. * Mercilessly hacked and occasionally improved since then via the * combined efforts of Van, Steve McCanne and Craig Leres of LBL. */ #include #include #include #include #include #include #include #include "interface.h" #include "savefile.h" #include "addrtoname.h" int fflag; /* don't translate "foreign" IP address */ int nflag; /* leave addresses as numbers */ int Nflag; /* remove domains from printed host names */ int pflag; /* don't go promiscuous */ int qflag; /* quick (shorter) output */ int tflag = 1; /* print packet arrival time */ int eflag; /* print ethernet header */ int vflag; /* verbose */ int xflag; /* print packet in hex */ int Oflag = 1; /* run filter code optimizer */ int Sflag; /* print raw TCP sequence numbers */ int dflag; /* print filter code */ char *program_name; long thiszone; /* gmt to local correction */ static void cleanup(); /* Length of saved portion of packet. */ int snaplen = DEFAULT_SNAPLEN; static int if_fd = -1; struct printer { void (*f)(); int type; }; static struct printer printers[] = { { ether_if_print, DLT_EN10MB }, { sl_if_print, DLT_SLIP }, { ppp_if_print, DLT_PPP }, { fddi_if_print, DLT_FDDI }, { null_if_print, DLT_NULL }, { 0, 0 }, }; void (*lookup_printer(type))() int type; { struct printer *p; for (p = printers; p->f; ++p) if (type == p->type) return p->f; error("unknown data link type 0x%x", type); /* NOTREACHED */ } void main(argc, argv) int argc; char **argv; { struct bpf_program *parse(); void bpf_dump(); int cnt = -1, i; struct timeb zt; struct bpf_program *fcode; int op; void (*printit)(); char *infile = 0; char *cmdbuf; int linktype; int err; u_long localnet; u_long netmask; char *RFileName = 0; /* -r argument */ char *WFileName = 0; /* -w argument */ char *device = 0; int precision = clock_sigfigs(); extern char *optarg; extern int optind, opterr; program_name = argv[0]; opterr = 0; while ((op = getopt(argc, argv, "c:defF:i:lnNOpqr:s:Stvw:xY")) != EOF) switch (op) { case 'c': cnt = atoi(optarg); break; case 'd': ++dflag; break; case 'e': ++eflag; break; case 'f': ++fflag; break; case 'F': infile = optarg; break; case 'i': device = optarg; break; case 'l': setlinebuf(stdout); break; case 'n': ++nflag; break; case 'N': ++Nflag; break; case 'O': Oflag = 0; break; case 'p': ++pflag; break; case 'q': ++qflag; break; case 'r': RFileName = optarg; break; case 's': snaplen = atoi(optarg); break; case 'S': ++Sflag; break; case 't': --tflag; break; case 'v': ++vflag; break; case 'w': WFileName = optarg; break; #ifdef YYDEBUG case 'Y': { extern int yydebug; yydebug = 1; } break; #endif case 'x': ++xflag; break; default: usage(); /* NOTREACHED */ } if (tflag > 0) { struct timeval now; struct timezone tz; if (gettimeofday(&now, &tz) < 0) { perror("tcpdump: gettimeofday"); exit(1); } thiszone = tz.tz_minuteswest * -60; if (localtime((time_t *)&now.tv_sec)->tm_isdst) thiszone += 3600; } if (RFileName) { /* * We don't need network access, so set it back to the user id. * Also, this prevents the user from reading anyone's * trace file. */ setuid(getuid()); err = sf_read_init(RFileName, &linktype, &thiszone, &snaplen, &precision); if (err) sf_err(err); localnet = 0; netmask = 0; if (fflag != 0) error("-f and -r options are incompatible"); } else { if (device == 0) { device = lookup_device(); if (device == 0) error("can't find any interfaces"); } if_fd = initdevice(device, pflag, &linktype); lookup_net(device, &localnet, &netmask); /* * Let user own process after socket has been opened. */ setuid(getuid()); } if (infile) cmdbuf = read_infile(infile); else cmdbuf = copy_argv(&argv[optind]); fcode = parse(cmdbuf, Oflag, linktype, netmask); if (dflag) { bpf_dump(fcode, dflag); exit(0); } init_addrtoname(fflag, localnet, netmask); (void)signal(SIGTERM, cleanup); (void)signal(SIGINT, cleanup); (void)signal(SIGHUP, cleanup); printit = lookup_printer(linktype); if (WFileName) { sf_write_init(WFileName, linktype, thiszone, snaplen, precision); printit = sf_write; } if (RFileName) { err = sf_read(fcode, cnt, snaplen, printit); if (err) sf_err(err); } else { fprintf(stderr, "%s: listening on %s\n", program_name, device); fflush(stderr); readloop(cnt, if_fd, fcode, printit); } exit(0); } /* make a clean exit on interrupts */ static void cleanup() { if (if_fd >= 0) { putc('\n', stderr); wrapup(if_fd); } exit(0); } void default_print(sp, length) register u_short *sp; register int length; { register u_int i; register int nshorts; nshorts = (unsigned) length / sizeof(u_short); i = 0; while (--nshorts >= 0) { if ((i++ % 8) == 0) (void)printf("\n\t\t\t"); (void)printf(" %04x", ntohs(*sp++)); } if (length & 1) { if ((i % 8) == 0) (void)printf("\n\t\t\t"); (void)printf(" %02x", *(u_char *)sp); } } void usage() { extern char version[]; (void)fprintf(stderr, "Version %s\n", version); (void)fprintf(stderr, "Usage: tcpdump [-deflnOpqtvx] [-c count] [-i interface]\n"); (void)fprintf(stderr, "\t\t[-r filename] [-w filename] [expr]\n"); exit(-1); }