X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/a0e19c0caef95fdcbace674de91e7c181d3bc866..75866fb1db0b52ce70940e113e48fa353fb00d1e:/tcpdump.c diff --git a/tcpdump.c b/tcpdump.c index 6476a3d4..837f14e9 100644 --- a/tcpdump.c +++ b/tcpdump.c @@ -78,7 +78,9 @@ The Regents of the University of California. All rights reserved.\n"; #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. + * in the opposite order works fine. For the most part anyway, because in + * FreeBSD declares bpf_dump() instead of . Thus + * interface.h takes care of it later to avoid a compiler warning. */ #ifdef HAVE_CAPSICUM #include @@ -161,6 +163,8 @@ The Regents of the University of California. All rights reserved.\n"; #include "print.h" +#include "diag-control.h" + #include "fptype.h" #ifndef PATH_MAX @@ -238,10 +242,6 @@ static int infoprint; char *program_name; -#ifdef HAVE_CASPER -cap_channel_t *capdns; -#endif - /* Forwards */ static NORETURN void error(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2); static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2); @@ -807,7 +807,7 @@ droproot(const char *username, const char *chroot_dir) error("Couldn't find user '%.32s'", username); #ifdef HAVE_LIBCAP_NG /* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */ -DIAG_OFF_CLANG(assign-enum) +DIAG_OFF_ASSIGN_ENUM capng_updatev( CAPNG_DROP, CAPNG_EFFECTIVE | CAPNG_PERMITTED, @@ -815,7 +815,7 @@ DIAG_OFF_CLANG(assign-enum) CAP_SETGID, CAP_SYS_CHROOT, -1); -DIAG_ON_CLANG(assign-enum) +DIAG_ON_ASSIGN_ENUM capng_apply(CAPNG_SELECT_BOTH); #endif /* HAVE_LIBCAP_NG */ @@ -843,6 +843,8 @@ MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars) char *filename = malloc(PATH_MAX + 1); if (filename == NULL) error("%s: malloc", __func__); + if (strlen(orig_name) == 0) + error("an empty string is not a valid file name"); /* Process with strftime if Gflag is set. */ if (Gflag != 0) { @@ -854,9 +856,25 @@ MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars) } /* There's no good way to detect an error in strftime since a return - * value of 0 isn't necessarily failure. + * value of 0 isn't necessarily failure; if orig_name is an empty + * string, the formatted string will be empty. + * + * However, the C90 standard says that, if there *is* a + * buffer overflow, the content of the buffer is undefined, + * so we must check for a buffer overflow. + * + * So we check above for an empty orig_name, and only call + * strftime() if it's non-empty, in which case the return + * value will only be 0 if the formatted date doesn't fit + * in the buffer. + * + * (We check above because, even if we don't use -G, we + * want a better error message than "tcpdump: : No such + * file or directory" for this case.) */ - strftime(filename, PATH_MAX, orig_name, local_tm); + if (strftime(filename, PATH_MAX, orig_name, local_tm) == 0) { + error("%s: strftime", __func__); + } } else { strncpy(filename, orig_name, PATH_MAX); } @@ -2008,6 +2026,8 @@ main(int argc, char **argv) /* Run with '-Z root' to restore old behaviour */ if (!username) username = WITH_USER; + else if (strcmp(username, "root") == 0) + username = NULL; } #endif @@ -2290,33 +2310,33 @@ main(int argc, char **argv) /* Initialize capng */ capng_clear(CAPNG_SELECT_BOTH); if (username) { -DIAG_OFF_CLANG(assign-enum) +DIAG_OFF_ASSIGN_ENUM capng_updatev( CAPNG_ADD, CAPNG_PERMITTED | CAPNG_EFFECTIVE, CAP_SETUID, CAP_SETGID, -1); -DIAG_ON_CLANG(assign-enum) +DIAG_ON_ASSIGN_ENUM } if (chroot_dir) { -DIAG_OFF_CLANG(assign-enum) +DIAG_OFF_ASSIGN_ENUM capng_update( CAPNG_ADD, CAPNG_PERMITTED | CAPNG_EFFECTIVE, CAP_SYS_CHROOT ); -DIAG_ON_CLANG(assign-enum) +DIAG_ON_ASSIGN_ENUM } if (WFileName) { -DIAG_OFF_CLANG(assign-enum) +DIAG_OFF_ASSIGN_ENUM capng_update( CAPNG_ADD, CAPNG_PERMITTED | CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE ); -DIAG_ON_CLANG(assign-enum) +DIAG_ON_ASSIGN_ENUM } capng_apply(CAPNG_SELECT_BOTH); #endif /* HAVE_LIBCAP_NG */ @@ -2382,17 +2402,44 @@ DIAG_ON_CLANG(assign-enum) #endif if (Cflag != 0 || Gflag != 0) { #ifdef HAVE_CAPSICUM - dumpinfo.WFileName = strdup(basename(WFileName)); + /* + * basename() and dirname() may modify their input buffer + * and they do since FreeBSD 12.0, but they didn't before. + * Hence use the return value only, but always assume the + * input buffer has been modified and would need to be + * reset before the next use. + */ + char *WFileName_copy; + + if ((WFileName_copy = strdup(WFileName)) == NULL) { + error("Unable to allocate memory for file %s", + WFileName); + } + DIAG_OFF_C11_EXTENSIONS + dumpinfo.WFileName = strdup(basename(WFileName_copy)); + DIAG_ON_C11_EXTENSIONS if (dumpinfo.WFileName == NULL) { error("Unable to allocate memory for file %s", WFileName); } - dumpinfo.dirfd = open(dirname(WFileName), + free(WFileName_copy); + + if ((WFileName_copy = strdup(WFileName)) == NULL) { + error("Unable to allocate memory for file %s", + WFileName); + } + DIAG_OFF_C11_EXTENSIONS + char *WFileName_dirname = dirname(WFileName_copy); + DIAG_ON_C11_EXTENSIONS + dumpinfo.dirfd = open(WFileName_dirname, O_DIRECTORY | O_RDONLY); if (dumpinfo.dirfd < 0) { error("unable to open directory %s", - dirname(WFileName)); + WFileName_dirname); } + free(WFileName_dirname); + free(WFileName_copy); + cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE); if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 && @@ -2641,7 +2688,7 @@ DIAG_ON_CLANG(assign-enum) free(cmdbuf); pcap_freecode(&fcode); - exit_tcpdump(status == -1 ? 1 : 0); + exit_tcpdump(status == -1 ? S_ERR_HOST_PROGRAM : S_SUCCESS); } /* @@ -2657,7 +2704,14 @@ static void memset(&new, 0, sizeof(new)); new.sa_handler = func; - if (sig == SIGCHLD) + if ((sig == SIGCHLD) +# ifdef SIGNAL_REQ_INFO + || (sig == SIGNAL_REQ_INFO) +# endif +# ifdef SIGNAL_FLUSH_PCAP + || (sig == SIGNAL_FLUSH_PCAP) +# endif + ) new.sa_flags = SA_RESTART; if (sigaction(sig, &new, &old) < 0) return (SIG_ERR); @@ -3127,7 +3181,7 @@ static void verbose_stats_dump(int sig _U_) } #endif /* _WIN32 */ -USES_APPLE_DEPRECATED_API +DIAG_OFF_DEPRECATION static void print_version(FILE *f) { @@ -3165,7 +3219,7 @@ print_version(FILE *f) # endif #endif /* __SANITIZE_ADDRESS__ or __has_feature */ } -USES_APPLE_RST +DIAG_ON_DEPRECATION static void print_usage(FILE *f)