X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/71393b1bcba896ecf18736ce1bae59bfedcbb9da..HEAD:/tcpdump.c diff --git a/tcpdump.c b/tcpdump.c index 56dc2145..e5975671 100644 --- a/tcpdump.c +++ b/tcpdump.c @@ -34,6 +34,9 @@ */ #include +#ifndef TCPDUMP_CONFIG_H_ +#error "The included config.h header is not from the tcpdump build." +#endif #include "netdissect-stdinc.h" @@ -137,11 +140,9 @@ The Regents of the University of California. All rights reserved.\n"; #include #endif /* __FreeBSD__ */ -#include "netdissect-stdinc.h" #include "netdissect.h" #include "interface.h" #include "addrtoname.h" -#include "pcap-missing.h" #include "ascii_strcasecmp.h" #include "print.h" @@ -165,11 +166,7 @@ The Regents of the University of California. All rights reserved.\n"; #endif static int Bflag; /* buffer size */ -#ifdef HAVE_PCAP_DUMP_FTELL64 static int64_t Cflag; /* rotate dump files after this many bytes */ -#else -static long Cflag; /* rotate dump files after this many bytes */ -#endif static int Cflag_count; /* Keep track of which file number we're writing */ static int Dflag; /* list available devices and exit */ #ifdef HAVE_PCAP_FINDALLDEVS_EX @@ -205,13 +202,15 @@ static int Qflag = -1; /* restrict captured packet by send/receive direction * static int Uflag; /* "unbuffered" output of dump files */ static int Wflag; /* recycle output files after this number of files */ static int WflagChars; +#if defined(HAVE_FORK) || defined(HAVE_VFORK) static char *zflag = NULL; /* compress each savefile using a specified command (like gzip or bzip2) */ +#endif static int timeout = 1000; /* default timeout = 1000 ms = 1 s */ #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE static int immediate_mode; #endif static int count_mode; -static u_int packets_skipped; +static u_int packets_to_skip; static int infodelay; static int infoprint; @@ -219,9 +218,17 @@ static int infoprint; char *program_name; /* Forwards */ +static int parse_int(const char *argname, const char *string, char **endp, + int minval, int maxval, int base); +static u_int parse_u_int(const char *argname, const char *string, char **endp, + u_int minval, u_int maxval, int base); +static int64_t parse_int64(const char *argname, const char *string, + char **endp, int64_t minval, int64_t maxval, int base); static void (*setsignal (int sig, void (*func)(int)))(int); static void cleanup(int); +#if defined(HAVE_FORK) || defined(HAVE_VFORK) static void child_cleanup(int); +#endif static void print_version(FILE *); static void print_usage(FILE *); @@ -609,7 +616,27 @@ show_remote_devices_and_exit(void) #define m_FLAG_USAGE "[ -m module ] ..." #endif -#define SHORTOPTS "aAbB:c:C:dDeE:fF:G:hHi:I" j_FLAG J_FLAG "KlLm:M:nNOpqQ:r:s:StT:uUvV:w:W:xXy:Yz:Z:#" +#if defined(HAVE_FORK) || defined(HAVE_VFORK) +#define z_FLAG "z:" +#define z_FLAG_USAGE "[ -z postrotate-command ] " +#else +#define z_FLAG +#define z_FLAG_USAGE +#endif + +#ifdef HAVE_LIBCRYPTO +#define E_FLAG "E:" +#define E_FLAG_USAGE "[ -E algo:secret ] " +#define M_FLAG "M:" +#define M_FLAG_USAGE "[ -M secret ] " +#else +#define E_FLAG +#define E_FLAG_USAGE +#define M_FLAG +#define M_FLAG_USAGE +#endif + +#define SHORTOPTS "aAbB:c:C:dDe" E_FLAG "fF:G:hHi:I" j_FLAG J_FLAG "KlLm:" M_FLAG "nNOpqQ:r:s:StT:uUvV:w:W:xXy:Y" z_FLAG "Z:#" /* * Long options. @@ -724,7 +751,7 @@ droproot(const char *username, const char *chroot_dir) { int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG); if (ret < 0) - error("capng_change_id(): return %d\n", ret); + error("capng_change_id(): return %d", ret); else fprintf(stderr, "dropped privs to %s\n", username); } @@ -1344,6 +1371,11 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf) } else if (status == PCAP_ERROR_PERM_DENIED && *cp != '\0') error("%s: %s\n(%s)", device, pcap_statustostr(status), cp); +#ifdef PCAP_ERROR_CAPTURE_NOTSUP + else if (status == PCAP_ERROR_CAPTURE_NOTSUP && *cp != '\0') + error("%s: %s\n(%s)", device, + pcap_statustostr(status), cp); +#endif #ifdef __FreeBSD__ else if (status == PCAP_ERROR_RFMON_NOTSUP && strncmp(device, "wlan", 4) == 0) { @@ -1361,7 +1393,7 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf) * specific case would be an error message that looks a bit odd. */ newdev[strlen(newdev)-1]++; - error("%s is not a monitor mode VAP\n" + error("%s is not a monitor mode VAP" "To create a new monitor mode VAP use:\n" " ifconfig %s create wlandev %s wlanmode monitor\n" "and use %s as the tcpdump interface", @@ -1422,7 +1454,6 @@ main(int argc, char **argv) const char *chroot_dir = NULL; #endif char *ret = NULL; - char *end; pcap_if_t *devlist; long devnum; int status; @@ -1645,26 +1676,24 @@ main(int argc, char **argv) break; case 'B': - Bflag = atoi(optarg)*1024; - if (Bflag <= 0) - error("invalid packet buffer size %s", optarg); + Bflag = parse_int("packet buffer size", optarg, NULL, 1, + INT_MAX, 10); + /* + * Will multiplying it by 1024 overflow? + */ + if (Bflag > INT_MAX / 1024) + error("packet buffer size %s is too large", optarg); + Bflag *= 1024; break; case 'c': - cnt = atoi(optarg); - if (cnt <= 0) - error("invalid packet count %s", optarg); + cnt = parse_int("packet count", optarg, NULL, 1, + INT_MAX, 10); break; case 'C': - errno = 0; -#ifdef HAVE_PCAP_DUMP_FTELL64 - Cflag = strtoint64_t(optarg, &endp, 10); -#else - Cflag = strtol(optarg, &endp, 10); -#endif - if (endp == optarg || errno != 0 || Cflag <= 0) - error("invalid file size %s", optarg); + Cflag = parse_int64("file size", optarg, &endp, 1, + INT64_MAX, 10); if (*endp == '\0') { /* @@ -1709,7 +1738,7 @@ main(int argc, char **argv) break; default: - error("invalid file size %s", optarg); + error("invalid file size %s (invalid units)", optarg); } /* @@ -1720,7 +1749,7 @@ main(int argc, char **argv) endp++; if (*endp != '\0') { /* Yes - error */ - error("invalid file size %s", optarg); + error("invalid file size %s (invalid units)", optarg); } } @@ -1728,7 +1757,7 @@ main(int argc, char **argv) * Will multiplying it by multiplier overflow? */ #ifdef HAVE_PCAP_DUMP_FTELL64 - if (Cflag > INT64_T_CONSTANT(0x7fffffffffffffff) / Cflagmult) + if (Cflag > INT64_MAX / Cflagmult) #else if (Cflag > LONG_MAX / Cflagmult) #endif @@ -1758,12 +1787,11 @@ main(int argc, char **argv) ++ndo->ndo_eflag; break; +#ifdef HAVE_LIBCRYPTO case 'E': -#ifndef HAVE_LIBCRYPTO - warning("crypto code not compiled in"); -#endif ndo->ndo_espsecret = optarg; break; +#endif case 'f': ++ndo->ndo_fflag; @@ -1774,9 +1802,8 @@ main(int argc, char **argv) break; case 'G': - Gflag = atoi(optarg); - if (Gflag < 0) - error("invalid number of seconds %s", optarg); + Gflag = parse_int("number of seconds", optarg, NULL, 0, + INT_MAX, 10); /* We will create one file initially. */ Gflag_count = 0; @@ -1850,13 +1877,12 @@ main(int argc, char **argv) } break; +#ifdef HAVE_LIBCRYPTO case 'M': /* TCP-MD5 shared secret */ -#ifndef HAVE_LIBCRYPTO - warning("crypto code not compiled in"); -#endif ndo->ndo_sigsecret = optarg; break; +#endif case 'n': ++ndo->ndo_nflag; @@ -1895,11 +1921,8 @@ main(int argc, char **argv) break; case 's': - ndo->ndo_snaplen = (int)strtol(optarg, &end, 0); - if (optarg == end || *end != '\0' - || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN) - error("invalid snaplen %s (must be >= 0 and <= %d)", - optarg, MAXIMUM_SNAPLEN); + ndo->ndo_snaplen = parse_int("snaplen", optarg, NULL, + 0, MAXIMUM_SNAPLEN, 0); break; case 'S': @@ -1978,9 +2001,8 @@ main(int argc, char **argv) break; case 'W': - Wflag = atoi(optarg); - if (Wflag <= 0) - error("invalid number of output files %s", optarg); + Wflag = parse_int("number of output files", optarg, + NULL, 1, INT_MAX, 10); WflagChars = getWflagChars(Wflag); break; @@ -2010,9 +2032,12 @@ main(int argc, char **argv) } break; #endif + +#if defined(HAVE_FORK) || defined(HAVE_VFORK) case 'z': zflag = optarg; break; +#endif case 'Z': username = optarg; @@ -2056,17 +2081,13 @@ main(int argc, char **argv) case OPTION_PRINT_SAMPLING: print = 1; ++ndo->ndo_Sflag; - ndo->ndo_print_sampling = atoi(optarg); - if (ndo->ndo_print_sampling <= 0) - error("invalid print sampling %s", optarg); + ndo->ndo_print_sampling = parse_int("print sampling", + optarg, NULL, 1, INT_MAX, 10); break; case OPTION_SKIP: - errno = 0; - packets_skipped = (u_int)strtoul(optarg, &end, 0); - if (optarg[0] == '-' || optarg == end || *end != '\0' || - errno != 0) - error("invalid packet skipped %s", optarg); + packets_to_skip = parse_u_int("packet skip count", + optarg, NULL, 0, INT_MAX, 0); break; #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION @@ -2100,6 +2121,27 @@ main(int argc, char **argv) /* NOTREACHED */ } + if (ndo->ndo_Aflag && ndo->ndo_xflag) + error("-A and -x[x] are mutually exclusive."); + if (ndo->ndo_Aflag && ndo->ndo_Xflag) + error("-A and -X[X] are mutually exclusive."); + if (ndo->ndo_xflag && ndo->ndo_Xflag) + error("-x[x] and -X[X] are mutually exclusive."); + if (Cflag != 0 && WFileName == NULL) + error("-C cannot be used without -w."); + if (Gflag != 0 && WFileName == NULL) + error("-G cannot be used without -w."); +#if defined(HAVE_FORK) || defined(HAVE_VFORK) + if (zflag != NULL && (WFileName == NULL || (Cflag == 0 && Gflag == 0))) + error("-z cannot be used without -w and (-C or -G)."); +#endif + + if (cnt != -1) + if ((int)packets_to_skip > (INT_MAX - cnt)) + // cnt + (int)packets_to_skip used in pcap_loop() call + error("Overflow (-c count) %d + (--skip count) %d", cnt, + (int)packets_to_skip); + if (Dflag) show_devices_and_exit(); #ifdef HAVE_PCAP_FINDALLDEVS_EX @@ -2123,7 +2165,7 @@ main(int argc, char **argv) } if (ndo->ndo_fflag != 0 && (VFileName != NULL || RFileName != NULL)) - error("-f can not be used with -V or -r"); + error("-f cannot be used with -V or -r."); if (VFileName != NULL && RFileName != NULL) error("-V and -r are mutually exclusive."); @@ -2191,11 +2233,11 @@ main(int argc, char **argv) VFile = fopen(VFileName, "r"); if (VFile == NULL) - error("Unable to open file: %s\n", pcap_strerror(errno)); + error("Unable to open file: %s", pcap_strerror(errno)); ret = get_next_file(VFile, VFileLine); if (!ret) - error("Nothing in %s\n", VFileName); + error("Nothing in %s", VFileName); RFileName = VFileLine; } @@ -2367,7 +2409,11 @@ DIAG_ON_WARN_UNUSED_RESULT #ifdef HAVE_PCAP_SET_OPTIMIZER_DEBUG pcap_set_optimizer_debug(dflag); #endif - if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) + /* + * netmask is in network byte order, pcap_compile() takes it + * in host byte order. + */ + if (pcap_compile(pd, &fcode, cmdbuf, Oflag, ntohl(netmask)) < 0) error("%s", pcap_geterr(pd)); if (dflag) { bpf_dump(&fcode, dflag); @@ -2382,6 +2428,7 @@ DIAG_ON_WARN_UNUSED_RESULT capdns = capdns_setup(); #endif /* HAVE_CASPER */ + // Both localnet and netmask are in network byte order. init_print(ndo, localnet, netmask); #ifndef _WIN32 @@ -2696,7 +2743,7 @@ DIAG_ON_ASSIGN_ENUM do { status = pcap_loop(pd, - cnt + (cnt == -1 ? 0 : packets_skipped), + (cnt == -1 ? -1 : cnt + (int)packets_to_skip), callback, pcap_userdata); if (WFileName == NULL) { /* @@ -2785,7 +2832,11 @@ DIAG_ON_ASSIGN_ENUM ndo->ndo_if_printer = get_if_printer(dlt); /* Free the old filter */ pcap_freecode(&fcode); - if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) + /* + * netmask is in network byte order, pcap_compile() takes it + * in host byte order. + */ + if (pcap_compile(pd, &fcode, cmdbuf, Oflag, ntohl(netmask)) < 0) error("%s", pcap_geterr(pd)); } @@ -2822,6 +2873,134 @@ DIAG_ON_ASSIGN_ENUM exit_tcpdump(status == -1 ? S_ERR_HOST_PROGRAM : S_SUCCESS); } +/* + * Routines to parse numerical command-line arguments and check for + * errors, including "too large for that type". + */ +static int +parse_int(const char *argname, const char *string, char **endpp, + int minval, int maxval, int base) +{ + long val; + char *endp; + + errno = 0; + val = strtol(string, &endp, base); + + /* + * Did it either not parse any of the string, find extra stuff + * at the end that the caller isn't interested in, or get + * another parsing error? + */ + if (string == endp || (endpp == NULL && *endp != '\0') || + (val == 0 && errno == EINVAL)) { + error("invalid %s \"%s\" (not a valid number)", argname, + string); + } + + /* + * Did it get a value that's out of range? + */ + if (((val == LONG_MAX || val == LONG_MIN) && errno == ERANGE) || + val < minval || val > maxval) { + error("invalid %s %s (must be >= %d and <= %d)", + argname, string, minval, maxval); + } + + /* + * OK, it passes all the tests. + */ + if (endpp != NULL) + *endpp = endp; + return ((int)val); +} + +static u_int +parse_u_int(const char *argname, const char *string, char **endpp, + u_int minval, u_int maxval, int base) +{ + unsigned long val; + char *endp; + + errno = 0; + + /* + * strtoul() does *NOT* report an error if the string + * begins with a minus sign. We do. + */ + if (*string == '-') { + error("invalid %s \"%s\" (not a valid unsigned number)", + argname, string); + } + + val = strtoul(string, &endp, base); + + /* + * Did it either not parse any of the string, find extra stuff + * at the end that the caller isn't interested in, or get + * another parsing error? + */ + if (string == endp || (endpp == NULL && *endp != '\0') || + (val == 0 && errno == EINVAL)) { + error("invalid %s \"%s\" (not a valid unsigned number)", + argname, string); + } + + /* + * Did it get a value that's out of range? + */ + if ((val == ULONG_MAX && errno == ERANGE) || + val < minval || val > maxval) { + error("invalid %s %s (must be >= %u and <= %u)", + argname, string, minval, maxval); + } + + /* + * OK, it passes all the tests. + */ + if (endpp != NULL) + *endpp = endp; + return ((u_int)val); +} + +static int64_t +parse_int64(const char *argname, const char *string, char **endpp, + int64_t minval, int64_t maxval, int base) +{ + intmax_t val; + char *endp; + + errno = 0; + val = strtoimax(string, &endp, base); + + /* + * Did it either not parse any of the string, find extra stuff + * at the end that the caller isn't interested in, or get + * another parsing error? + */ + if (string == endp || (endpp == NULL && *endp != '\0') || + (val == 0 && errno == EINVAL)) { + error("invalid %s \"%s\" (not a valid number)", argname, + string); + } + + /* + * Did it get a value that's out of range? + */ + if (((val == INTMAX_MAX || val == INTMAX_MIN) && errno == ERANGE) || + val < minval || val > maxval) { + error("invalid %s %s (must be >= %" PRId64 " and <= %" PRId64 ")", + argname, string, minval, maxval); + } + + /* + * OK, it passes all the tests. + */ + if (endpp != NULL) + *endpp = endp; + return ((int64_t)val); +} + /* * Catch a signal. */ @@ -2957,8 +3136,8 @@ compress_savefile(const char *filename) child = fork_subprocess(); if (child == -1) { fprintf(stderr, - "compress_savefile: fork failed: %s\n", - pcap_strerror(errno)); + "%s: fork failed: %s\n", + __func__, pcap_strerror(errno)); return; } if (child != 0) { @@ -2977,24 +3156,15 @@ compress_savefile(const char *filename) #endif if (execlp(zflag, zflag, filename, (char *)NULL) == -1) fprintf(stderr, - "compress_savefile: execlp(%s, %s) failed: %s\n", - zflag, - filename, - pcap_strerror(errno)); + "%s: execlp(%s, %s) failed: %s\n", + __func__, zflag, filename, pcap_strerror(errno)); #ifdef HAVE_FORK exit(S_ERR_HOST_PROGRAM); #else _exit(S_ERR_HOST_PROGRAM); #endif } -#else /* HAVE_FORK && HAVE_VFORK */ -static void -compress_savefile(const char *filename) -{ - fprintf(stderr, - "compress_savefile failed. Functionality not implemented under your system\n"); -} -#endif /* HAVE_FORK && HAVE_VFORK */ +#endif /* HAVE_FORK || HAVE_VFORK */ static void close_old_dump_file(struct dump_info *dump_info) @@ -3004,11 +3174,13 @@ close_old_dump_file(struct dump_info *dump_info) */ pcap_dump_close(dump_info->pdd); +#if defined(HAVE_FORK) || defined(HAVE_VFORK) /* * Compress the file we just closed, if the user asked for it. */ if (zflag != NULL) compress_savefile(dump_info->CurrentFileName); +#endif } static void @@ -3059,7 +3231,7 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s dump_info = (struct dump_info *)user; - if (packets_captured <= packets_skipped) + if (packets_captured <= packets_to_skip) return; /* @@ -3191,7 +3363,7 @@ dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) dump_info = (struct dump_info *)user; - if (packets_captured <= packets_skipped) + if (packets_captured <= packets_to_skip) return; pcap_dump((u_char *)dump_info->pdd, h, sp); @@ -3213,7 +3385,7 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) ++infodelay; - if (!count_mode && packets_captured > packets_skipped) + if (!count_mode && packets_captured > packets_to_skip) pretty_print_packet((netdissect_options *)user, h, sp, packets_captured); --infodelay; @@ -3307,7 +3479,7 @@ print_usage(FILE *f) (void)fprintf(f, "Usage: %s [-AbdDefhHI" J_FLAG "KlLnNOpqStuUvxX#] [ -B size ] [ -c count ] [--count]\n", program_name); (void)fprintf(f, -"\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n"); +"\t\t[ -C file_size ] " E_FLAG_USAGE "[ -F file ] [ -G seconds ]\n"); (void)fprintf(f, "\t\t[ -i interface ]" IMMEDIATE_MODE_USAGE j_FLAG_USAGE "\n"); (void)fprintf(f, @@ -3317,11 +3489,11 @@ print_usage(FILE *f) "\t\t" m_FLAG_USAGE "\n"); #endif (void)fprintf(f, -"\t\t[ -M secret ] [ --number ] [ --print ]\n"); +"\t\t" M_FLAG_USAGE "[ --number ] [ --print ]\n"); (void)fprintf(f, "\t\t[ --print-sampling nth ] [ -Q in|out|inout ] [ -r file ]\n"); (void)fprintf(f, -"\t\t[ -s snaplen ] [ -T type ] [ --version ]\n"); +"\t\t[ -s snaplen ] [ --skip count ] [ -T type ] [ --version ]\n"); (void)fprintf(f, "\t\t[ -V file ] [ -w file ] [ -W filecount ] [ -y datalinktype ]\n"); #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION @@ -3329,5 +3501,5 @@ print_usage(FILE *f) "\t\t[ --time-stamp-precision precision ] [ --micro ] [ --nano ]\n"); #endif (void)fprintf(f, -"\t\t[ -z postrotate-command ] [ -Z user ] [ expression ]\n"); +"\t\t" z_FLAG_USAGE "[ -Z user ] [ expression ]\n"); }