X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/e1e0824e40f4bfaaec7636f1e452911a6b8f7eca..87889ba67add1e8abd77fdaacbfd831ee9335bcc:/tcpdump.c diff --git a/tcpdump.c b/tcpdump.c index 2e9a5055..d77b4bda 100644 --- a/tcpdump.c +++ b/tcpdump.c @@ -43,6 +43,17 @@ The Regents of the University of California. All rights reserved.\n"; #include "config.h" #endif +/* + * Mac OS X may ship pcap.h from libpcap 0.6 with a libpcap based on + * 0.8. That means it has pcap_findalldevs() but the header doesn't + * define pcap_if_t, meaning that we can't actually *use* pcap_findalldevs(). + */ +#ifdef HAVE_PCAP_FINDALLDEVS +#ifndef HAVE_PCAP_IF_T +#undef HAVE_PCAP_FINDALLDEVS +#endif +#endif + #include #ifdef WIN32 @@ -53,7 +64,7 @@ extern int SIZE_BUF; #define uint UINT #endif /* WIN32 */ -#ifdef HAVE_SMI_H +#ifdef USE_LIBSMI #include #endif @@ -66,6 +77,17 @@ extern int SIZE_BUF; #else #include "getopt_long.h" #endif +/* Capsicum-specific code requires macros from , which will fail + * to compile if has already been included; including the headers + * in the opposite order works fine. + */ +#ifdef HAVE_CAPSICUM +#include +#include +#include +#include +#include +#endif /* HAVE_CAPSICUM */ #include #include #include @@ -441,6 +463,9 @@ struct dump_info { char *CurrentFileName; pcap_t *pd; pcap_dumper_t *p; +#ifdef HAVE_CAPSICUM + int dirfd; +#endif }; #ifdef HAVE_PCAP_SET_TSTAMP_TYPE @@ -604,12 +629,6 @@ show_devices_and_exit (void) #define J_FLAG #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */ -#ifdef HAVE_PCAP_FINDALLDEVS -#ifndef HAVE_PCAP_IF_T -#undef HAVE_PCAP_FINDALLDEVS -#endif -#endif - #ifdef HAVE_PCAP_FINDALLDEVS #define D_FLAG "D" #else @@ -648,10 +667,10 @@ show_devices_and_exit (void) * component of the entry for the long option, and have a case for that * option in the switch statement. */ -#define OPTION_NUMBER 128 -#define OPTION_VERSION 129 +#define OPTION_VERSION 128 +#define OPTION_TSTAMP_PRECISION 129 -static struct option longopts[] = { +static const struct option longopts[] = { #if defined(HAVE_PCAP_CREATE) || defined(WIN32) { "buffer-size", required_argument, NULL, 'B' }, #endif @@ -664,6 +683,9 @@ static struct option longopts[] = { #ifdef HAVE_PCAP_SET_TSTAMP_TYPE { "time-stamp-type", required_argument, NULL, 'j' }, { "list-time-stamp-types", no_argument, NULL, 'J' }, +#endif +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + { "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION}, #endif { "dont-verify-checksums", no_argument, NULL, 'K' }, { "list-data-link-types", no_argument, NULL, 'L' }, @@ -682,7 +704,7 @@ static struct option longopts[] = { { "debug-filter-parser", no_argument, NULL, 'Y' }, #endif { "relinquish-privileges", required_argument, NULL, 'Z' }, - { "number", no_argument, NULL, OPTION_NUMBER }, + { "number", no_argument, NULL, '#' }, { "version", no_argument, NULL, OPTION_VERSION }, { NULL, 0, NULL, 0 } }; @@ -711,7 +733,10 @@ droproot(const char *username, const char *chroot_dir) #ifdef HAVE_CAP_NG_H int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG); if (ret < 0) { - printf("error : ret %d\n", ret); + fprintf(stderr, "error : ret %d\n", ret); + } + else { + printf("dropped privs to %s\n", username); } /* We don't need CAP_SETUID and CAP_SETGID */ capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID); @@ -730,6 +755,9 @@ droproot(const char *username, const char *chroot_dir) pcap_strerror(errno)); exit(1); } + else { + printf("dropped privs to %s\n", username); + } #endif /* HAVE_CAP_NG_H */ } else { @@ -840,6 +868,36 @@ get_next_file(FILE *VFile, char *ptr) return ret; } +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION +static int +tstamp_precision_from_string(const char *precision) +{ + if (strncmp(precision, "nano", strlen("nano")) == 0) + return PCAP_TSTAMP_PRECISION_NANO; + + if (strncmp(precision, "micro", strlen("micro")) == 0) + return PCAP_TSTAMP_PRECISION_MICRO; + + return -EINVAL; +} + +static const char * +tstamp_precision_to_string(int precision) +{ + switch (precision) { + + case PCAP_TSTAMP_PRECISION_MICRO: + return "micro"; + + case PCAP_TSTAMP_PRECISION_NANO: + return "nano"; + + default: + return "unknown"; + } +} +#endif + int main(int argc, char **argv) { @@ -870,6 +928,11 @@ main(int argc, char **argv) #endif int status; FILE *VFile; +#ifdef HAVE_CAPSICUM + cap_rights_t rights; + int cansandbox; +#endif /* HAVE_CAPSICUM */ + #ifdef WIN32 if(wsockinit() != 0) return 1; #endif /* WIN32 */ @@ -897,15 +960,22 @@ main(int argc, char **argv) else program_name = argv[0]; + /* + * On platforms where the CPU doesn't support unaligned loads, + * force unaligned accesses to abort with SIGBUS, rather than + * being fixed up (slowly) by the OS kernel; on those platforms, + * misaligned accesses are bugs, and we want tcpdump to crash so + * that the bugs are reported. + */ if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0) error("%s", ebuf); -#ifdef LIBSMI +#ifdef USE_LIBSMI smiInit("tcpdump"); #endif while ( - (op = getopt_long(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:Rs:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:", longopts, NULL)) != -1) + (op = getopt_long(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:Rs:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#", longopts, NULL)) != -1) switch (op) { case 'a': @@ -1081,7 +1151,7 @@ main(int argc, char **argv) break; case 'm': -#ifdef LIBSMI +#ifdef USE_LIBSMI if (smiLoadModule(optarg) == 0) { error("could not load MIB module %s", optarg); } @@ -1266,7 +1336,7 @@ main(int argc, char **argv) username = strdup(optarg); break; - case OPTION_NUMBER: + case '#': gndo->ndo_packet_number = 1; break; @@ -1275,6 +1345,14 @@ main(int argc, char **argv) exit(0); break; +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + case OPTION_TSTAMP_PRECISION: + gndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg); + if (gndo->ndo_tstamp_precision < 0) + error("unsupported time stamp precision"); + break; +#endif + default: print_usage(); exit(1); @@ -1366,9 +1444,22 @@ main(int argc, char **argv) RFileName = VFileLine; } +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + pd = pcap_open_offline_with_tstamp_precision(RFileName, + gndo->ndo_tstamp_precision, ebuf); +#else pd = pcap_open_offline(RFileName, ebuf); +#endif + if (pd == NULL) error("%s", ebuf); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_READ); + if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 && + errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } +#endif dlt = pcap_datalink(pd); dlt_name = pcap_datalink_val_to_name(dlt); if (dlt_name == NULL) { @@ -1413,6 +1504,15 @@ main(int argc, char **argv) if (Jflag) show_tstamp_types_and_exit(device, pd); #endif +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + status = pcap_set_tstamp_precision(pd, gndo->ndo_tstamp_precision); + if (status != 0) + error("%s: Can't set %ssecond time stamp precision: %s", + device, + tstamp_precision_to_string(gndo->ndo_tstamp_precision), + pcap_statustostr(status)); +#endif + /* * Is this an interface that supports monitor mode? */ @@ -1624,6 +1724,21 @@ main(int argc, char **argv) if (pcap_setfilter(pd, &fcode) < 0) error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + if (RFileName == NULL && VFileName == NULL) { + static const unsigned long cmds[] = { BIOCGSTATS }; + + cap_rights_init(&rights, CAP_IOCTL, CAP_READ); + if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 && + errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } + if (cap_ioctls_limit(pcap_fileno(pd), cmds, + sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) { + error("unable to limit ioctls on pcap descriptor"); + } + } +#endif if (WFileName) { pcap_dumper_t *p; /* Do not exceed the default PATH_MAX for files. */ @@ -1645,9 +1760,32 @@ main(int argc, char **argv) #endif if (p == NULL) error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); + if (cap_rights_limit(fileno(pcap_dump_file(p)), &rights) < 0 && + errno != ENOSYS) { + error("unable to limit dump descriptor"); + } +#endif if (Cflag != 0 || Gflag != 0) { - callback = dump_packet_and_trunc; +#ifdef HAVE_CAPSICUM + dumpinfo.WFileName = strdup(basename(WFileName)); + dumpinfo.dirfd = open(dirname(WFileName), + O_DIRECTORY | O_RDONLY); + if (dumpinfo.dirfd < 0) { + error("unable to open directory %s", + dirname(WFileName)); + } + cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, + CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE); + if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 && + errno != ENOSYS) { + error("unable to limit directory rights"); + } +#else /* !HAVE_CAPSICUM */ dumpinfo.WFileName = WFileName; +#endif + callback = dump_packet_and_trunc; dumpinfo.pd = pd; dumpinfo.p = p; pcap_userdata = (u_char *)&dumpinfo; @@ -1717,6 +1855,15 @@ main(int argc, char **argv) (void)fflush(stderr); } #endif /* WIN32 */ + +#ifdef HAVE_CAPSICUM + cansandbox = (nflag && VFileName == NULL && zflag == NULL); + if (cansandbox && cap_enter() < 0 && errno != ENOSYS) + error("unable to enter the capability mode"); + if (cap_sandboxed()) + fprintf(stderr, "capability mode sandbox enabled\n"); +#endif /* HAVE_CAPSICUM */ + do { status = pcap_loop(pd, cnt, callback, pcap_userdata); if (WFileName == NULL) { @@ -1764,6 +1911,13 @@ main(int argc, char **argv) pd = pcap_open_offline(RFileName, ebuf); if (pd == NULL) error("%s", ebuf); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_READ); + if (cap_rights_limit(fileno(pcap_file(pd)), + &rights) < 0 && errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } +#endif new_dlt = pcap_datalink(pd); if (WFileName && new_dlt != dlt) error("%s: new dlt does not match original", RFileName); @@ -1932,6 +2086,9 @@ static void dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) { struct dump_info *dump_info; +#ifdef HAVE_CAPSICUM + cap_rights_t rights; +#endif ++packets_captured; @@ -1960,6 +2117,11 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s /* If the time is greater than the specified window, rotate */ if (t - Gflag_time >= Gflag) { +#ifdef HAVE_CAPSICUM + FILE *fp; + int fd; +#endif + /* Update the Gflag_time */ Gflag_time = t; /* Update Gflag_count */ @@ -2013,13 +2175,36 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); capng_apply(CAPNG_EFFECTIVE); #endif /* HAVE_CAP_NG_H */ +#ifdef HAVE_CAPSICUM + fd = openat(dump_info->dirfd, + dump_info->CurrentFileName, + O_CREAT | O_WRONLY | O_TRUNC, 0644); + if (fd < 0) { + error("unable to open file %s", + dump_info->CurrentFileName); + } + fp = fdopen(fd, "w"); + if (fp == NULL) { + error("unable to fdopen file %s", + dump_info->CurrentFileName); + } + dump_info->p = pcap_dump_fopen(dump_info->pd, fp); +#else /* !HAVE_CAPSICUM */ dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); +#endif #ifdef HAVE_CAP_NG_H capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); capng_apply(CAPNG_EFFECTIVE); #endif /* HAVE_CAP_NG_H */ if (dump_info->p == NULL) error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); + if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)), + &rights) < 0 && errno != ENOSYS) { + error("unable to limit dump descriptor"); + } +#endif } } @@ -2029,6 +2214,11 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s * file could put it over Cflag. */ if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) { +#ifdef HAVE_CAPSICUM + FILE *fp; + int fd; +#endif + /* * Close the current file and open a new one. */ @@ -2051,9 +2241,31 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s if (dump_info->CurrentFileName == NULL) error("dump_packet_and_trunc: malloc"); MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars); +#ifdef HAVE_CAPSICUM + fd = openat(dump_info->dirfd, dump_info->CurrentFileName, + O_CREAT | O_WRONLY | O_TRUNC, 0644); + if (fd < 0) { + error("unable to open file %s", + dump_info->CurrentFileName); + } + fp = fdopen(fd, "w"); + if (fp == NULL) { + error("unable to fdopen file %s", + dump_info->CurrentFileName); + } + dump_info->p = pcap_dump_fopen(dump_info->pd, fp); +#else /* !HAVE_CAPSICUM */ dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); +#endif if (dump_info->p == NULL) error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); + if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)), + &rights) < 0 && errno != ENOSYS) { + error("unable to limit dump descriptor"); + } +#endif } pcap_dump((u_char *)dump_info->p, h, sp); @@ -2107,7 +2319,8 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) /* * 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. + * Rather than pass it all the way down, we set this member + * of the netdissect_options structure. */ ndo->ndo_snapend = sp + h->caplen; @@ -2117,6 +2330,11 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) hdrlen = (*print_info->p.printer)(h, sp); } + /* + * Restore the original snapend, as a printer might have + * changed it. + */ + ndo->ndo_snapend = sp + h->caplen; if (ndo->ndo_Xflag) { /* * Print the raw packet data in hex and ASCII. @@ -2215,7 +2433,7 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) static void ndo_default_print(netdissect_options *ndo, const u_char *bp, u_int length) { - hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and identation string */ + hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and indentation string */ } void @@ -2257,6 +2475,7 @@ static void verbose_stats_dump(int sig _U_) } #endif +USES_APPLE_DEPRECATED_API static void print_version(void) { @@ -2290,17 +2509,18 @@ print_version(void) (void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION)); #endif -#if defined(HAVE_SMI_H) +#ifdef USE_LIBSMI (void)fprintf (stderr, "SMI-library: %s\n", smi_version_string); #endif } +USES_APPLE_RST static void print_usage(void) { print_version(); (void)fprintf(stderr, -"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name); +"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name); (void)fprintf(stderr, "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n"); (void)fprintf(stderr, @@ -2310,7 +2530,13 @@ print_usage(void) "\t\t[ -Q in|out|inout ]\n"); #endif (void)fprintf(stderr, -"\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ --version ] [ -V file ]\n"); +"\t\t[ -r file ] [ -s snaplen ] "); +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + (void)fprintf(stderr, "[ --time-stamp-precision precision ]\n"); + (void)fprintf(stderr, +"\t\t"); +#endif + (void)fprintf(stderr, "[ -T type ] [ --version ] [ -V file ]\n"); (void)fprintf(stderr, "\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z command ]\n"); (void)fprintf(stderr,