X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/b53994535a4f53c1411b6b37fdd1e40a21263bbc..c0de704a5331dd3b9bd060dd0969163025186c0e:/tcpdump.c diff --git a/tcpdump.c b/tcpdump.c index 75224e4c..65e108a0 100644 --- a/tcpdump.c +++ b/tcpdump.c @@ -26,11 +26,11 @@ */ #ifndef lint -static const char copyright[] = +static const char copyright[] _U_ = "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\ The Regents of the University of California. All rights reserved.\n"; -static const char rcsid[] = - "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.183 2002-08-06 04:36:12 guy Exp $ (LBL)"; +static const char rcsid[] _U_ = + "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.267 2006-02-09 20:33:49 hannes Exp $ (LBL)"; #endif /* @@ -56,45 +56,41 @@ extern int SIZE_BUF; #define uint UINT #endif /* WIN32 */ +#ifdef HAVE_SMI_H +#include +#endif + #include #include #include #include #include +#ifndef WIN32 +#include +#include +#include +#endif /* WIN32 */ - +#include "netdissect.h" #include "interface.h" #include "addrtoname.h" #include "machdep.h" #include "setsignal.h" #include "gmt2local.h" +#include "pcap-missing.h" + +#ifndef NAME_MAX +#define NAME_MAX 255 +#endif + +netdissect_options Gndo; +netdissect_options *gndo = &Gndo; -int aflag; /* translate network and broadcast addresses */ int dflag; /* print filter code */ -int eflag; /* print ethernet header */ -int fflag; /* don't translate "foreign" IP address */ -int nflag; /* leave addresses as numbers */ -int Nflag; /* remove domains from printed host names */ -int Oflag = 1; /* run filter code optimizer */ -int pflag; /* don't go promiscuous */ -int qflag; /* quick (shorter) output */ -int Rflag = 1; /* print sequence # field in AH/ESP*/ -int sflag = 0; /* use the libsmi to translate OIDs */ -int Sflag; /* print raw TCP sequence numbers */ -int tflag = 1; /* print packet arrival time */ -int uflag = 0; /* Print undecoded NFS handles */ -int vflag; /* verbose */ -int xflag; /* print packet in hex */ -int Xflag; /* print packet in ascii as well as hex */ -off_t Cflag = 0; /* rotate dump files after this many bytes */ -int Aflag = 0; /* print packet only in ascii observing LF, CR, TAB, SPACE */ - -char *espsecret = NULL; /* ESP secret key */ - -int packettype; - -int infodelay; -int infoprint; +int Lflag; /* list available data link types and exit */ + +static int infodelay; +static int infoprint; char *program_name; @@ -103,23 +99,43 @@ int32_t thiszone; /* seconds offset from gmt to local time */ /* Forwards */ static RETSIGTYPE cleanup(int); static void usage(void) __attribute__((noreturn)); +static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn)); -static void dump_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *); +static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *); +static void ndo_default_print(netdissect_options *, const u_char *, u_int); +static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *); +static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *); +static void droproot(const char *, const char *); +static void ndo_error(netdissect_options *ndo, const char *fmt, ...); +static void ndo_warning(netdissect_options *ndo, const char *fmt, ...); #ifdef SIGINFO RETSIGTYPE requestinfo(int); #endif -/* Length of saved portion of packet. */ -int snaplen = DEFAULT_SNAPLEN; +#if defined(USE_WIN32_MM_TIMER) + #include + static UINT timer_id; + static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR); +#elif defined(HAVE_ALARM) + static void verbose_stats_dump(int sig); +#endif + +static void info(int); +static u_int packets_captured; + +typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *); struct printer { - pcap_handler f; + if_printer f; int type; }; static struct printer printers[] = { { arcnet_if_print, DLT_ARCNET }, +#ifdef DLT_ARCNET_LINUX + { arcnet_linux_if_print, DLT_ARCNET_LINUX }, +#endif { ether_if_print, DLT_EN10MB }, { token_if_print, DLT_IEEE802 }, #ifdef DLT_LANE8023 @@ -132,9 +148,16 @@ static struct printer printers[] = { { cip_if_print, DLT_ATM_CLIP }, #endif { sl_if_print, DLT_SLIP }, +#ifdef DLT_SLIP_BSDOS { sl_bsdos_if_print, DLT_SLIP_BSDOS }, +#endif { ppp_if_print, DLT_PPP }, +#ifdef DLT_PPP_WITHDIRECTION + { ppp_if_print, DLT_PPP_WITHDIRECTION }, +#endif +#ifdef DLT_PPP_BSDOS { ppp_bsdos_if_print, DLT_PPP_BSDOS }, +#endif { fddi_if_print, DLT_FDDI }, { null_if_print, DLT_NULL }, #ifdef DLT_LOOP @@ -174,11 +197,77 @@ static struct printer printers[] = { #endif #ifdef DLT_SUNATM { sunatm_if_print, DLT_SUNATM }, +#endif +#ifdef DLT_IP_OVER_FC + { ipfc_if_print, DLT_IP_OVER_FC }, +#endif +#ifdef DLT_PRISM_HEADER + { prism_if_print, DLT_PRISM_HEADER }, +#endif +#ifdef DLT_IEEE802_11_RADIO + { ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO }, +#endif +#ifdef DLT_ENC + { enc_if_print, DLT_ENC }, +#endif +#ifdef DLT_SYMANTEC_FIREWALL + { symantec_if_print, DLT_SYMANTEC_FIREWALL }, +#endif +#ifdef DLT_APPLE_IP_OVER_IEEE1394 + { ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 }, +#endif +#ifdef DLT_JUNIPER_ATM1 + { juniper_atm1_print, DLT_JUNIPER_ATM1 }, +#endif +#ifdef DLT_JUNIPER_ATM2 + { juniper_atm2_print, DLT_JUNIPER_ATM2 }, +#endif +#ifdef DLT_JUNIPER_MFR + { juniper_mfr_print, DLT_JUNIPER_MFR }, +#endif +#ifdef DLT_JUNIPER_MLFR + { juniper_mlfr_print, DLT_JUNIPER_MLFR }, +#endif +#ifdef DLT_JUNIPER_MLPPP + { juniper_mlppp_print, DLT_JUNIPER_MLPPP }, +#endif +#ifdef DLT_JUNIPER_PPPOE + { juniper_pppoe_print, DLT_JUNIPER_PPPOE }, +#endif +#ifdef DLT_JUNIPER_PPPOE_ATM + { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM }, +#endif +#ifdef DLT_JUNIPER_GGSN + { juniper_ggsn_print, DLT_JUNIPER_GGSN }, +#endif +#ifdef DLT_JUNIPER_ES + { juniper_es_print, DLT_JUNIPER_ES }, +#endif +#ifdef DLT_JUNIPER_MONITOR + { juniper_monitor_print, DLT_JUNIPER_MONITOR }, +#endif +#ifdef DLT_JUNIPER_SERVICES + { juniper_services_print, DLT_JUNIPER_SERVICES }, +#endif +#ifdef DLT_JUNIPER_ETHER + { juniper_ether_print, DLT_JUNIPER_ETHER }, +#endif +#ifdef DLT_JUNIPER_PPP + { juniper_ppp_print, DLT_JUNIPER_PPP }, +#endif +#ifdef DLT_JUNIPER_FRELAY + { juniper_frelay_print, DLT_JUNIPER_FRELAY }, +#endif +#ifdef DLT_JUNIPER_CHDLC + { juniper_chdlc_print, DLT_JUNIPER_CHDLC }, +#endif +#ifdef DLT_MFR + { mfr_if_print, DLT_MFR }, #endif { NULL, 0 }, }; -static pcap_handler +static if_printer lookup_printer(int type) { struct printer *p; @@ -187,7 +276,7 @@ lookup_printer(int type) if (type == p->type) return p->f; - error("unknown data link type %d", type); + return NULL; /* NOTREACHED */ } @@ -197,43 +286,218 @@ extern int optind; extern int opterr; extern char *optarg; +struct print_info { + if_printer printer; +}; + struct dump_info { char *WFileName; pcap_t *pd; pcap_dumper_t *p; }; +static void +show_dlts_and_exit(pcap_t *pd) +{ + int n_dlts; + int *dlts = 0; + const char *dlt_name; + + n_dlts = pcap_list_datalinks(pd, &dlts); + if (n_dlts < 0) + error("%s", pcap_geterr(pd)); + else if (n_dlts == 0 || !dlts) + error("No data link types."); + + (void) fprintf(stderr, "Data link types (use option -y to set):\n"); + + while (--n_dlts >= 0) { + dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]); + if (dlt_name != NULL) { + (void) fprintf(stderr, " %s (%s)", dlt_name, + pcap_datalink_val_to_description(dlts[n_dlts])); + + /* + * OK, does tcpdump handle that type? + */ + if (lookup_printer(dlts[n_dlts]) == NULL) + (void) fprintf(stderr, " (not supported)"); + putchar('\n'); + } else { + (void) fprintf(stderr, " DLT %d (not supported)\n", + dlts[n_dlts]); + } + } + free(dlts); + exit(0); +} + +/* + * Set up flags that might or might not be supported depending on the + * version of libpcap we're using. + */ +#ifdef WIN32 +#define B_FLAG "B:" +#define B_FLAG_USAGE " [ -B size ]" +#else /* WIN32 */ +#define B_FLAG +#define B_FLAG_USAGE +#endif /* WIN32 */ + +#ifdef HAVE_PCAP_FINDALLDEVS +#ifndef HAVE_PCAP_IF_T +#undef HAVE_PCAP_FINDALLDEVS +#endif +#endif + +#ifdef HAVE_PCAP_FINDALLDEVS +#define D_FLAG "D" +#else +#define D_FLAG +#endif + +#ifdef HAVE_PCAP_DUMP_FLUSH +#define U_FLAG "U" +#else +#define U_FLAG +#endif + +#ifndef WIN32 +/* Drop root privileges and chroot if necessary */ +static void +droproot(const char *username, const char *chroot_dir) +{ + struct passwd *pw = NULL; + + if (chroot_dir && !username) { + fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n"); + exit(1); + } + + pw = getpwnam(username); + if (pw) { + if (chroot_dir) { + if (chroot(chroot_dir) != 0 || chdir ("/") != 0) { + fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n", + chroot_dir, pcap_strerror(errno)); + exit(1); + } + } + if (initgroups(pw->pw_name, pw->pw_gid) != 0 || + setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) { + fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n", + username, + (unsigned long)pw->pw_uid, + (unsigned long)pw->pw_gid, + pcap_strerror(errno)); + exit(1); + } + } + else { + fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n", + username); + exit(1); + } +} +#endif /* WIN32 */ + +static int +getWflagChars(int x) +{ + int c = 0; + + x -= 1; + while (x > 0) { + c += 1; + x /= 10; + } + + return c; +} + + +static void +MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars) +{ + char *filename = malloc(NAME_MAX + 1); + + /* Process with strftime if Gflag is set. */ + if (Gflag != 0) { + struct tm *local_tm; + + /* Convert Gflag_time to a usable format */ + if ((local_tm = localtime(&Gflag_time)) == NULL) { + error("MakeTimedFilename: localtime"); + } + + /* There's no good way to detect an error in strftime since a return + * value of 0 isn't necessarily failure. + */ + strftime(filename, NAME_MAX, orig_name, local_tm); + } else { + strncpy(filename, orig_name, NAME_MAX); + } + + if (cnt == 0 && max_chars == 0) + strncpy(buffer, filename, NAME_MAX + 1); + else + if (snprintf(buffer, NAME_MAX + 1, "%s%0*d", filename, max_chars, cnt) > NAME_MAX) + /* Report an error if the filename is too large */ + error("too many output files or filename is too long (> %d)", NAME_MAX); + free(filename); +} + +static int tcpdump_printf(netdissect_options *ndo _U_, + const char *fmt, ...) +{ + + va_list args; + int ret; + + va_start(args, fmt); + ret=vfprintf(stdout, fmt, args); + va_end(args); + + return ret; +} + int main(int argc, char **argv) { register int cnt, op, i; bpf_u_int32 localnet, netmask; - register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName; - pcap_handler printer; + register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName, *WFileNameAlt; + pcap_handler callback; + int type; struct bpf_program fcode; #ifndef WIN32 RETSIGTYPE (*oldhandler)(int); #endif + struct print_info printinfo; struct dump_info dumpinfo; u_char *pcap_userdata; char ebuf[PCAP_ERRBUF_SIZE]; + char *username = NULL; + char *chroot_dir = NULL; #ifdef HAVE_PCAP_FINDALLDEVS pcap_if_t *devpointer; int devnum; #endif + int status; #ifdef WIN32 - int ii; - DWORD dwVersion; - DWORD dwWindowsMajorVersion; - u_int UserBufferSize=1000000; -#endif - -#ifdef WIN32 - dwVersion=GetVersion(); /* get the OS version */ - dwWindowsMajorVersion = (DWORD)(LOBYTE(LOWORD(dwVersion))); - if(wsockinit()!=0) return 1; + u_int UserBufferSize = 1000000; + if(wsockinit() != 0) return 1; #endif /* WIN32 */ + gndo->ndo_Oflag=1; + gndo->ndo_Rflag=1; + gndo->ndo_dlt=-1; + gndo->ndo_default_print=ndo_default_print; + gndo->ndo_printf=tcpdump_printf; + gndo->ndo_error=ndo_error; + gndo->ndo_warning=ndo_warning; + gndo->ndo_snaplen = DEFAULT_SNAPLEN; + cnt = -1; device = NULL; infile = NULL; @@ -253,26 +517,16 @@ main(int argc, char **argv) opterr = 0; while ( -#ifdef WIN32 - (op = getopt(argc, argv, "aAB:c:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1) -#else /* WIN32 */ -#ifdef HAVE_PCAP_FINDALLDEVS - (op = getopt(argc, argv, "aAc:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1) -#else /* HAVE_PCAP_FINDALLDEVS */ - (op = getopt(argc, argv, "aAc:C:deE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1) -#endif /* HAVE_PCAP_FINDALLDEVS */ -#endif /* WIN32 */ + (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:G:i:lLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:YZ:")) != -1) switch (op) { case 'a': - ++aflag; + /* compatibility for old -a */ break; - case 'A': - ++xflag; - ++Xflag; - ++Aflag; - break; + case 'A': + ++Aflag; + break; #ifdef WIN32 case 'B': @@ -314,6 +568,10 @@ main(int argc, char **argv) return 0; #endif /* HAVE_PCAP_FINDALLDEVS */ + case 'L': + Lflag++; + break; + case 'e': ++eflag; break; @@ -322,7 +580,7 @@ main(int argc, char **argv) #ifndef HAVE_LIBCRYPTO warning("crypto code not compiled in"); #endif - espsecret = optarg; + gndo->ndo_espsecret = optarg; break; case 'f': @@ -333,6 +591,21 @@ main(int argc, char **argv) infile = optarg; break; + case 'G': + Gflag = atoi(optarg); + if (Gflag < 0) + error("invalid number of seconds %s", optarg); + + /* We will create one file initially. */ + Gflag_count = 0; + + /* Grab the current time for rotation use. */ + if ((Gflag_time = time(NULL)) == (time_t)-1) { + error("main: can't get current time: %s", + pcap_strerror(errno)); + } + break; + case 'i': if (optarg[0] == '0' && optarg[1] == 0) error("Invalid adapter index"); @@ -369,11 +642,24 @@ main(int argc, char **argv) break; case 'l': +#ifdef WIN32 + /* + * _IOLBF is the same as _IOFBF in Microsoft's C + * libraries; the only alternative they offer + * is _IONBF. + * + * XXX - this should really be checking for MSVC++, + * not WIN32, if, for example, MinGW has its own + * C library that is more UNIX-compatible. + */ + setvbuf(stdout, NULL, _IONBF, 0); +#else /* WIN32 */ #ifdef HAVE_SETLINEBUF setlinebuf(stdout); #else setvbuf(stdout, NULL, _IOLBF, 0); #endif +#endif /* WIN32 */ break; case 'n': @@ -386,15 +672,24 @@ main(int argc, char **argv) case 'm': #ifdef LIBSMI - if (smiLoadModule(optarg) == 0) { + if (smiLoadModule(optarg) == 0) { error("could not load MIB module %s", optarg); - } + } sflag = 1; #else (void)fprintf(stderr, "%s: ignoring option `-m %s' ", program_name, optarg); (void)fprintf(stderr, "(no libsmi support)\n"); #endif + break; + + case 'M': + /* TCP-MD5 shared secret */ +#ifndef HAVE_LIBCRYPTO + warning("crypto code not compiled in"); +#endif + tcpmd5secret = optarg; + break; case 'O': Oflag = 0; @@ -406,6 +701,7 @@ main(int argc, char **argv) case 'q': ++qflag; + ++suppress_default_print; break; case 'r': @@ -433,7 +729,7 @@ main(int argc, char **argv) break; case 't': - --tflag; + ++tflag; break; case 'T': @@ -451,6 +747,10 @@ main(int argc, char **argv) packettype = PT_SNMP; else if (strcasecmp(optarg, "cnfp") == 0) packettype = PT_CNFP; + else if (strcasecmp(optarg, "tftp") == 0) + packettype = PT_TFTP; + else if (strcasecmp(optarg, "aodv") == 0) + packettype = PT_AODV; else error("unknown packet type `%s'", optarg); break; @@ -459,6 +759,12 @@ main(int argc, char **argv) ++uflag; break; +#ifdef HAVE_PCAP_DUMP_FLUSH + case 'U': + ++Uflag; + break; +#endif + case 'v': ++vflag; break; @@ -467,48 +773,127 @@ main(int argc, char **argv) WFileName = optarg; break; + case 'W': + Wflag = atoi(optarg); + if (Wflag < 0) + error("invalid number of output files %s", optarg); + WflagChars = getWflagChars(Wflag); + break; + case 'x': ++xflag; + ++suppress_default_print; break; case 'X': - ++xflag; ++Xflag; + ++suppress_default_print; break; -#ifdef YYDEBUG + case 'y': + gndo->ndo_dltname = optarg; + gndo->ndo_dlt = + pcap_datalink_name_to_val(gndo->ndo_dltname); + if (gndo->ndo_dlt < 0) + error("invalid data link type %s", gndo->ndo_dltname); + break; + +#if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG) case 'Y': { /* Undocumented flag */ +#ifdef HAVE_PCAP_DEBUG + extern int pcap_debug; + pcap_debug = 1; +#else extern int yydebug; yydebug = 1; +#endif } break; #endif + case 'Z': + if (optarg) { + username = strdup(optarg); + } + else { + usage(); + /* NOTREACHED */ + } + break; + default: usage(); /* NOTREACHED */ } - if (aflag && nflag) - error("-a and -n options are incompatible"); + switch (tflag) { - if (tflag > 0) + case 0: /* Default */ + case 4: /* Default + Date*/ thiszone = gmt2local(0); + break; + + case 1: /* No time stamp */ + case 2: /* Unix timeval style */ + case 3: /* Microseconds since previous packet */ + case 5: /* Microseconds since first packet */ + break; + + default: /* Not supported */ + error("only -t, -tt, -ttt, -tttt and -ttttt are supported"); + break; + } + +#ifdef WITH_CHROOT + /* if run as root, prepare for chrooting */ + if (getuid() == 0 || geteuid() == 0) { + /* future extensibility for cmd-line arguments */ + if (!chroot_dir) + chroot_dir = WITH_CHROOT; + } +#endif + +#ifdef WITH_USER + /* if run as root, prepare for dropping root privileges */ + if (getuid() == 0 || geteuid() == 0) { + /* Run with '-Z root' to restore old behaviour */ + if (!username) + username = WITH_USER; + } +#endif if (RFileName != NULL) { + int dlt; + const char *dlt_name; + +#ifndef WIN32 /* - * 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. + * We don't need network access, so relinquish any set-UID + * or set-GID privileges we have (if any). + * + * We do *not* want set-UID privileges when opening a + * trace file, as that might let the user read other + * people's trace files (especially if we're set-UID + * root). */ -#ifndef WIN32 - setuid(getuid()); + if (setgid(getgid()) != 0 || setuid(getuid()) != 0 ) + fprintf(stderr, "Warning: setgid/setuid failed !\n"); #endif /* WIN32 */ - pd = pcap_open_offline(RFileName, ebuf); if (pd == NULL) error("%s", ebuf); + dlt = pcap_datalink(pd); + dlt_name = pcap_datalink_val_to_name(dlt); + if (dlt_name == NULL) { + fprintf(stderr, "reading from file %s, link-type %u\n", + RFileName, dlt); + } else { + fprintf(stderr, + "reading from file %s, link-type %s (%s)\n", + RFileName, dlt_name, + pcap_datalink_val_to_description(dlt)); + } localnet = 0; netmask = 0; if (fflag != 0) @@ -520,21 +905,16 @@ main(int argc, char **argv) error("%s", ebuf); } #ifdef WIN32 + if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char + { //a Unicode string has a \0 as second byte (so strlen() is 1) + fprintf(stderr, "%s: listening on %ws\n", program_name, device); + } else { - if (!(dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4)) /* Windows '95 */ - { - if(device[1]!=0) - device=(char*)SChar2WChar(device); - } - else{ - for (ii=0;ii<(signed)strlen(device);ii++) - for (ii=strlen(device)-1;ii>0&&(device[ii]==' '||device[ii]=='\t');ii--)device[ii]='\0'; - for (ii=0;ii<(signed)strlen(device)&&(device[ii]==' '||device[ii]=='\t');ii++); - strcpy(device,device+ii); - } + fprintf(stderr, "%s: listening on %s\n", program_name, device); } - PrintCapBegins (program_name,device); + + fflush(stderr); #endif /* WIN32 */ *ebuf = '\0'; pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf); @@ -542,12 +922,40 @@ main(int argc, char **argv) error("%s", ebuf); else if (*ebuf) warning("%s", ebuf); + /* + * Let user own process after socket has been opened. + */ +#ifndef WIN32 + if (setgid(getgid()) != 0 || setuid(getuid()) != 0) + fprintf(stderr, "Warning: setgid/setuid failed !\n"); +#endif /* WIN32 */ #ifdef WIN32 if(UserBufferSize != 1000000) if(pcap_setbuff(pd, UserBufferSize)==-1){ error("%s", pcap_geterr(pd)); } #endif /* WIN32 */ + if (Lflag) + show_dlts_and_exit(pd); + if (gndo->ndo_dlt >= 0) { +#ifdef HAVE_PCAP_SET_DATALINK + if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0) + error("%s", pcap_geterr(pd)); +#else + /* + * We don't actually support changing the + * data link type, so we only let them + * set it to what it already is. + */ + if (gndo->ndo_dlt != pcap_datalink(pd)) { + error("%s is not one of the DLTs supported by this device\n", + gndo->ndo_dltname); + } +#endif + (void)fprintf(stderr, "%s: data link type %s\n", + program_name, gndo->ndo_dltname); + (void)fflush(stderr); + } i = pcap_snapshot(pd); if (snaplen < i) { warning("snaplen raised from %d to %d", snaplen, i); @@ -558,12 +966,6 @@ main(int argc, char **argv) netmask = 0; warning("%s", ebuf); } - /* - * Let user own process after socket has been opened. - */ -#ifndef WIN32 - setuid(getuid()); -#endif /* WIN32 */ } if (infile) cmdbuf = read_infile(infile); @@ -578,7 +980,11 @@ main(int argc, char **argv) exit(0); } init_addrtoname(localnet, netmask); + init_checksum(); +#ifndef WIN32 + (void)setsignal(SIGPIPE, cleanup); +#endif /* WIN32 */ (void)setsignal(SIGTERM, cleanup); (void)setsignal(SIGINT, cleanup); /* Cooperate with nohup(1) */ @@ -590,62 +996,177 @@ main(int argc, char **argv) if (pcap_setfilter(pd, &fcode) < 0) error("%s", pcap_geterr(pd)); if (WFileName) { - pcap_dumper_t *p = pcap_dump_open(pd, WFileName); + pcap_dumper_t *p; + /* Do not exceed the default NAME_MAX for files. */ + WFileNameAlt = (char *)malloc(NAME_MAX + 1); + + if (WFileNameAlt == NULL) + error("malloc of WFileNameAlt"); + + /* We do not need numbering for dumpfiles if Cflag isn't set. */ + if (Cflag != 0) + MakeFilename(WFileNameAlt, WFileName, 0, WflagChars); + else + MakeFilename(WFileNameAlt, WFileName, 0, 0); + + p = pcap_dump_open(pd, WFileNameAlt); + free(WFileNameAlt); if (p == NULL) error("%s", pcap_geterr(pd)); - if (Cflag != 0) { - printer = dump_and_trunc; + if (Cflag != 0 || Gflag != 0) { + callback = dump_packet_and_trunc; dumpinfo.WFileName = WFileName; dumpinfo.pd = pd; dumpinfo.p = p; pcap_userdata = (u_char *)&dumpinfo; } else { - printer = pcap_dump; + callback = dump_packet; pcap_userdata = (u_char *)p; } } else { - printer = lookup_printer(pcap_datalink(pd)); - pcap_userdata = 0; + type = pcap_datalink(pd); + printinfo.printer = lookup_printer(type); + if (printinfo.printer == NULL) { + gndo->ndo_dltname = pcap_datalink_val_to_name(type); + if (gndo->ndo_dltname != NULL) + error("unsupported data link type %s", + gndo->ndo_dltname); + else + error("unsupported data link type %d", type); + } + callback = print_packet; + pcap_userdata = (u_char *)&printinfo; + } +#ifndef WIN32 + /* + * We cannot do this earlier, because we want to be able to open + * the file (if done) for writing before giving up permissions. + */ + if (getuid() == 0 || geteuid() == 0) { + if (username || chroot_dir) + droproot(username, chroot_dir); + } +#endif /* WIN32 */ #ifdef SIGINFO - (void)setsignal(SIGINFO, requestinfo); + (void)setsignal(SIGINFO, requestinfo); +#endif + + if (vflag > 0 && WFileName) { + /* + * When capturing to a file, "-v" means tcpdump should, + * every 10 secodns, "v"erbosely report the number of + * packets captured. + */ +#ifdef USE_WIN32_MM_TIMER + /* call verbose_stats_dump() each 1000 +/-100msec */ + timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC); + setvbuf(stderr, NULL, _IONBF, 0); +#elif defined(HAVE_ALARM) + (void)setsignal(SIGALRM, verbose_stats_dump); + alarm(1); #endif } + #ifndef WIN32 if (RFileName == NULL) { - (void)fprintf(stderr, "%s: listening on %s\n", - program_name, device); + int dlt; + const char *dlt_name; + + if (!vflag && !WFileName) { + (void)fprintf(stderr, + "%s: verbose output suppressed, use -v or -vv for full protocol decode\n", + program_name); + } else + (void)fprintf(stderr, "%s: ", program_name); + dlt = pcap_datalink(pd); + dlt_name = pcap_datalink_val_to_name(dlt); + if (dlt_name == NULL) { + (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n", + device, dlt, snaplen); + } else { + (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n", + device, dlt_name, + pcap_datalink_val_to_description(dlt), snaplen); + } (void)fflush(stderr); } #endif /* WIN32 */ - if (pcap_loop(pd, cnt, printer, pcap_userdata) < 0) { + status = pcap_loop(pd, cnt, callback, pcap_userdata); + if (WFileName == NULL) { + /* + * We're printing packets. Flush the printed output, + * so it doesn't get intermingled with error output. + */ + if (status == -2) { + /* + * We got interrupted, so perhaps we didn't + * manage to finish a line we were printing. + * Print an extra newline, just in case. + */ + putchar('\n'); + } + (void)fflush(stdout); + } + if (status == -1) { + /* + * Error. Report it. + */ (void)fprintf(stderr, "%s: pcap_loop: %s\n", program_name, pcap_geterr(pd)); - cleanup(0); - pcap_close(pd); - exit(1); } - if (RFileName == NULL) + if (RFileName == NULL) { + /* + * We're doing a live capture. Report the capture + * statistics. + */ info(1); + } pcap_close(pd); - exit(0); + exit(status == -1 ? 1 : 0); } /* make a clean exit on interrupts */ static RETSIGTYPE -cleanup(int signo) +cleanup(int signo _U_) { +#ifdef USE_WIN32_MM_TIMER + if (timer_id) + timeKillEvent(timer_id); + timer_id = 0; +#elif defined(HAVE_ALARM) + alarm(0); +#endif - /* Can't print the summary if reading from a savefile */ +#ifdef HAVE_PCAP_BREAKLOOP + /* + * We have "pcap_breakloop()"; use it, so that we do as little + * as possible in the signal handler (it's probably not safe + * to do anything with standard I/O streams in a signal handler - + * the ANSI C standard doesn't say it is). + */ + pcap_breakloop(pd); +#else + /* + * We don't have "pcap_breakloop()"; this isn't safe, but + * it's the best we can do. Print the summary if we're + * not reading from a savefile - i.e., if we're doing a + * live capture - and exit. + */ if (pd != NULL && pcap_file(pd) == NULL) { + /* + * We got interrupted, so perhaps we didn't + * manage to finish a line we were printing. + * Print an extra newline, just in case. + */ + putchar('\n'); (void)fflush(stdout); - putc('\n', stderr); info(1); } - if (signo) - exit(0); + exit(0); +#endif } -void +static void info(register int verbose) { struct pcap_stat stat; @@ -658,6 +1179,11 @@ info(register int verbose) if (!verbose) fprintf(stderr, "%s: ", program_name); + (void)fprintf(stderr, "%u packets captured", packets_captured); + if (!verbose) + fputs(", ", stderr); + else + putc('\n', stderr); (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv); if (!verbose) fputs(", ", stderr); @@ -668,87 +1194,217 @@ info(register int verbose) } static void -reverse(char *s) +dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) { - int i, j, c; + struct dump_info *dump_info; + char *name; - for (i = 0, j = strlen(s) - 1; i < j; i++, j--) { - c = s[i]; - s[i] = s[j]; - s[j] = c; - } -} + ++packets_captured; + ++infodelay; -static void -swebitoa(unsigned int n, char *s) -{ - unsigned int i; + dump_info = (struct dump_info *)user; - i = 0; - do { - s[i++] = n % 10 + '0'; - } while ((n /= 10) > 0); + /* + * XXX - this won't force the file to rotate on the specified time + * boundary, but it will rotate on the first packet received after the + * specified Gflag number of seconds. Note: if a Gflag time boundary + * and a Cflag size boundary coincide, the time rotation will occur + * first thereby cancelling the Cflag boundary (since the file should + * be 0). + */ + if (Gflag != 0) { + /* Check if it is time to rotate */ + time_t t; + + /* Get the current time */ + if ((t = time(NULL)) == (time_t)-1) { + error("dump_and_trunc_packet: can't get current_time: %s", + pcap_strerror(errno)); + } - s[i] = '\0'; - reverse(s); -} -static void -dump_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) -{ - struct dump_info *info; - static uint cnt = 2; - char *name; + /* If the time is greater than the specified window, rotate */ + if (t - Gflag_time >= Gflag) { + /* Update the Gflag_time */ + Gflag_time = t; + /* Update Gflag_count */ + Gflag_count++; + /* + * Close the current file and open a new one. + */ + pcap_dump_close(dump_info->p); + + /* + * Check to see if we've exceeded the Wflag (when + * not using Cflag). + */ + if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) { + (void)fprintf(stderr, "Maximum file limit reached: %d\n", + Wflag); + exit(0); + /* NOTREACHED */ + } + /* Allocate space for max filename + \0. */ + name = (char *)malloc(NAME_MAX + 1); + if (name == NULL) + error("dump_packet_and_trunc: malloc"); + /* + * This is always the first file in the Cflag + * rotation: e.g. 0 + * We also don't need numbering if Cflag is not set. + */ + if (Cflag != 0) + MakeFilename(name, dump_info->WFileName, 0, + WflagChars); + else + MakeFilename(name, dump_info->WFileName, 0, 0); - info = (struct dump_info *)user; + dump_info->p = pcap_dump_open(dump_info->pd, name); + free(name); + if (dump_info->p == NULL) + error("%s", pcap_geterr(pd)); + } + } /* * XXX - this won't prevent capture files from getting * larger than Cflag - the last packet written to the * file could put it over Cflag. */ - if (ftell((FILE *)info->p) > Cflag) { - name = (char *) malloc(strlen(info->WFileName) + 4); + if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) { + /* + * Close the current file and open a new one. + */ + pcap_dump_close(dump_info->p); + Cflag_count++; + if (Wflag > 0) { + if (Cflag_count >= Wflag) + Cflag_count = 0; + } + name = (char *)malloc(NAME_MAX + 1); if (name == NULL) - error("dump_and_trunc: malloc"); - strcpy(name, info->WFileName); - swebitoa(cnt, name + strlen(info->WFileName)); - cnt++; - pcap_dump_close(info->p); - info->p = pcap_dump_open(info->pd, name); + error("dump_packet_and_trunc: malloc"); + MakeFilename(name, dump_info->WFileName, Cflag_count, WflagChars); + dump_info->p = pcap_dump_open(dump_info->pd, name); free(name); - if (info->p == NULL) + if (dump_info->p == NULL) error("%s", pcap_geterr(pd)); } - pcap_dump((u_char *)info->p, h, sp); + pcap_dump((u_char *)dump_info->p, h, sp); +#ifdef HAVE_PCAP_DUMP_FLUSH + if (Uflag) + pcap_dump_flush(dump_info->p); +#endif + + --infodelay; + if (infoprint) + info(0); } -/* Like default_print() but data need not be aligned */ -void -default_print_unaligned(register const u_char *cp, register u_int length) +static void +dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) { - register u_int i, s; - register int nshorts; + ++packets_captured; + ++infodelay; + + pcap_dump(user, h, sp); +#ifdef HAVE_PCAP_DUMP_FLUSH + if (Uflag) + pcap_dump_flush((pcap_dumper_t *)user); +#endif + + --infodelay; + if (infoprint) + info(0); +} + +static void +print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) +{ + struct print_info *print_info; + u_int hdrlen; + + ++packets_captured; + + ++infodelay; + ts_print(&h->ts); + + print_info = (struct print_info *)user; + + /* + * Some printers want to check that they're not walking off the + * end of the packet. + * Rather than pass it all the way down, we set this global. + */ + snapend = sp + h->caplen; + + hdrlen = (*print_info->printer)(h, sp); if (Xflag) { - ascii_print(cp, length); - return; - } - nshorts = (u_int) length / sizeof(u_short); - i = 0; - while (--nshorts >= 0) { - if ((i++ % 8) == 0) - (void)printf("\n\t\t\t"); - s = *cp++; - (void)printf(" %02x%02x", s, *cp++); - } - if (length & 1) { - if ((i % 8) == 0) - (void)printf("\n\t\t\t"); - (void)printf(" %02x", *cp); + /* + * Print the raw packet data in hex and ASCII. + */ + if (Xflag > 1) { + /* + * Include the link-layer header. + */ + hex_and_ascii_print("\n\t", sp, h->caplen); + } else { + /* + * Don't include the link-layer header - and if + * we have nothing past the link-layer header, + * print nothing. + */ + if (h->caplen > hdrlen) + hex_and_ascii_print("\n\t", sp + hdrlen, + h->caplen - hdrlen); + } + } else if (xflag) { + /* + * Print the raw packet data in hex. + */ + if (xflag > 1) { + /* + * Include the link-layer header. + */ + hex_print("\n\t", sp, h->caplen); + } else { + /* + * Don't include the link-layer header - and if + * we have nothing past the link-layer header, + * print nothing. + */ + if (h->caplen > hdrlen) + hex_print("\n\t", sp + hdrlen, + h->caplen - hdrlen); + } + } else if (Aflag) { + /* + * Print the raw packet data in ASCII. + */ + if (Aflag > 1) { + /* + * Include the link-layer header. + */ + ascii_print(sp, h->caplen); + } else { + /* + * Don't include the link-layer header - and if + * we have nothing past the link-layer header, + * print nothing. + */ + if (h->caplen > hdrlen) + ascii_print(sp + hdrlen, h->caplen - hdrlen); + } } + + putchar('\n'); + + --infodelay; + if (infoprint) + info(0); } #ifdef WIN32 @@ -771,22 +1427,30 @@ default_print_unaligned(register const u_char *cp, register u_int length) * "Wpcap_version" information on Windows. */ char WDversion[]="current-cvs.tcpdump.org"; +#if !defined(HAVE_GENERATED_VERSION) char version[]="current-cvs.tcpdump.org"; +#endif char pcap_version[]="current-cvs.tcpdump.org"; - char Wpcap_version[]="3.0 alpha"; + char Wpcap_version[]="3.1"; #endif /* - * By default, print the packet out in hex. + * By default, print the specified data out in hex and ASCII. */ +static void +ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length) +{ + hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */ +} + void -default_print(register const u_char *bp, register u_int length) +default_print(const u_char *bp, u_int length) { - default_print_unaligned(bp, length); + ndo_default_print(gndo, bp, length); } #ifdef SIGINFO -RETSIGTYPE requestinfo(int signo) +RETSIGTYPE requestinfo(int signo _U_) { if (infodelay) ++infoprint; @@ -795,32 +1459,105 @@ RETSIGTYPE requestinfo(int signo) } #endif +/* + * Called once each second in verbose mode while dumping to file + */ +#ifdef USE_WIN32_MM_TIMER +void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_, + DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_) +{ + struct pcap_stat stat; + + if (infodelay == 0 && pcap_stats(pd, &stat) >= 0) + fprintf(stderr, "Got %u\r", packets_captured); +} +#elif defined(HAVE_ALARM) +static void verbose_stats_dump(int sig _U_) +{ + struct pcap_stat stat; + + if (infodelay == 0 && pcap_stats(pd, &stat) >= 0) + fprintf(stderr, "Got %u\r", packets_captured); + alarm(1); +} +#endif + static void usage(void) { extern char version[]; +#ifndef HAVE_PCAP_LIB_VERSION +#if defined(WIN32) || defined(HAVE_PCAP_VERSION) extern char pcap_version[]; +#else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */ + static char pcap_version[] = "unknown"; +#endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */ +#endif /* HAVE_PCAP_LIB_VERSION */ +#ifdef HAVE_PCAP_LIB_VERSION #ifdef WIN32 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); - (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version); -#else +#else /* WIN32 */ (void)fprintf(stderr, "%s version %s\n", program_name, version); - (void)fprintf(stderr, "libpcap version %s\n", pcap_version); #endif /* WIN32 */ - (void)fprintf(stderr, + (void)fprintf(stderr, "%s\n",pcap_lib_version()); +#else /* HAVE_PCAP_LIB_VERSION */ #ifdef WIN32 -"Usage: %s [-aAdDeflnNOpqRStuvxX] [-B size] [-c count] [ -C file_size ]\n", program_name); + (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); + (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version); #else /* WIN32 */ -#ifdef HAVE_PCAP_FINDALLDEVS -"Usage: %s [-aAdDeflnNOpqRStuvxX] [-c count] [ -C file_size ]\n", program_name); -#else /* HAVE_PCAP_FINDALLDEVS */ -"Usage: %s [-aAdeflnNOpqRStuvxX] [-c count] [ -C file_size ]\n", program_name); -#endif /* HAVE_PCAP_FINDALLDEVS */ + (void)fprintf(stderr, "%s version %s\n", program_name, version); + (void)fprintf(stderr, "libpcap version %s\n", pcap_version); #endif /* WIN32 */ +#endif /* HAVE_PCAP_LIB_VERSION */ + (void)fprintf(stderr, +"Usage: %s [-aAd" D_FLAG "eflLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [-c count] [ -C file_size ]\n", program_name); + (void)fprintf(stderr, +"\t\t[ -E algo:secret ] [ -F file ] [ -G seconds ] [ -i interface ]\n"); (void)fprintf(stderr, -"\t\t[ -F file ] [ -i interface ] [ -r file ] [ -s snaplen ]\n"); +"\t\t[ -M secret ] [ -r file ] [ -s snaplen ] [ -T type ] [ -w file ]\n"); (void)fprintf(stderr, -"\t\t[ -T type ] [ -w file ] [ -E algo:secret ] [ expression ]\n"); +"\t\t[ -W filecount ] [ -y datalinktype ] [ -Z user ]\n"); + (void)fprintf(stderr, +"\t\t[ expression ]\n"); + exit(1); +} + + + +/* VARARGS */ +static void +ndo_error(netdissect_options *ndo _U_, const char *fmt, ...) +{ + va_list ap; + + (void)fprintf(stderr, "%s: ", program_name); + va_start(ap, fmt); + (void)vfprintf(stderr, fmt, ap); + va_end(ap); + if (*fmt) { + fmt += strlen(fmt); + if (fmt[-1] != '\n') + (void)fputc('\n', stderr); + } exit(1); + /* NOTREACHED */ } + +/* VARARGS */ +static void +ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...) +{ + va_list ap; + + (void)fprintf(stderr, "%s: WARNING: ", program_name); + va_start(ap, fmt); + (void)vfprintf(stderr, fmt, ap); + va_end(ap); + if (*fmt) { + fmt += strlen(fmt); + if (fmt[-1] != '\n') + (void)fputc('\n', stderr); + } +} +