X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/9c4af7213cc2543a1f5586d8f2c19f86aa0cbe72..fdd0467bcd46ea0d472111adedd21f43d6d4d15e:/tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index 2ac7757f..65b7e769 100644
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -122,7 +122,6 @@ The Regents of the University of California.  All rights reserved.\n";
 #include "interface.h"
 #include "addrtoname.h"
 #include "machdep.h"
-#include "setsignal.h"
 #include "gmt2local.h"
 #include "pcap-missing.h"
 #include "ascii_strcasecmp.h"
@@ -140,7 +139,11 @@ The Regents of the University of California.  All rights reserved.\n";
 #endif
 
 static int Bflag;			/* buffer size */
+#ifdef HAVE_PCAP_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 */
 /*
@@ -185,26 +188,18 @@ cap_channel_t *capdns;
 #endif
 
 /* Forwards */
-static void error(const char *, ...)
-     __attribute__((noreturn))
-#ifdef __ATTRIBUTE___FORMAT_OK
-     __attribute__((format (printf, 1, 2)))
-#endif /* __ATTRIBUTE___FORMAT_OK */
-     ;
-static void warning(const char *, ...)
-#ifdef __ATTRIBUTE___FORMAT_OK
-     __attribute__((format (printf, 1, 2)))
-#endif /* __ATTRIBUTE___FORMAT_OK */
-     ;
-static void exit_tcpdump(int) __attribute__((noreturn));
-static RETSIGTYPE cleanup(int);
-static RETSIGTYPE child_cleanup(int);
+static NORETURN void error(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static NORETURN void exit_tcpdump(int);
+static void (*setsignal (int sig, void (*func)(int)))(int);
+static void cleanup(int);
+static void child_cleanup(int);
 static void print_version(void);
 static void print_usage(void);
-static void show_tstamp_types_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
-static void show_dlts_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
+static NORETURN void show_tstamp_types_and_exit(pcap_t *, const char *device);
+static NORETURN void show_dlts_and_exit(pcap_t *, const char *device);
 #ifdef HAVE_PCAP_FINDALLDEVS
-static void show_devices_and_exit (void) __attribute__((noreturn));
+static NORETURN void show_devices_and_exit(void);
 #endif
 
 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
@@ -213,7 +208,7 @@ static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 static void droproot(const char *, const char *);
 
 #ifdef SIGNAL_REQ_INFO
-RETSIGTYPE requestinfo(int);
+void requestinfo(int);
 #endif
 
 #if defined(USE_WIN32_MM_TIMER)
@@ -253,6 +248,7 @@ struct dump_info {
 	char	*CurrentFileName;
 	pcap_t	*pd;
 	pcap_dumper_t *p;
+	netdissect_options *ndo;
 #ifdef HAVE_CAPSICUM
 	int	dirfd;
 #endif
@@ -562,6 +558,7 @@ show_devices_and_exit (void)
 #define OPTION_VERSION		128
 #define OPTION_TSTAMP_PRECISION	129
 #define OPTION_IMMEDIATE_MODE	130
+#define OPTION_PRINT		131
 
 static const struct option longopts[] = {
 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
@@ -601,6 +598,7 @@ static const struct option longopts[] = {
 #endif
 	{ "relinquish-privileges", required_argument, NULL, 'Z' },
 	{ "number", no_argument, NULL, '#' },
+	{ "print", no_argument, NULL, OPTION_PRINT },
 	{ "version", no_argument, NULL, OPTION_VERSION },
 	{ NULL, 0, NULL, 0 }
 };
@@ -1045,10 +1043,16 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf)
 		supports_monitor_mode = 1;
 	else
 		supports_monitor_mode = 0;
-	status = pcap_set_snaplen(pc, ndo->ndo_snaplen);
-	if (status != 0)
-		error("%s: Can't set snapshot length: %s",
-		    device, pcap_statustostr(status));
+	if (ndo->ndo_snaplen != 0) {
+		/*
+		 * A snapshot length was explicitly specified;
+		 * use it.
+		 */
+		status = pcap_set_snaplen(pc, ndo->ndo_snaplen);
+		if (status != 0)
+			error("%s: Can't set snapshot length: %s",
+			    device, pcap_statustostr(status));
+	}
 	status = pcap_set_promisc(pc, !pflag);
 	if (status != 0)
 		error("%s: Can't set promiscuous mode: %s",
@@ -1149,6 +1153,12 @@ open_interface(const char *device, netdissect_options *ndo, char *ebuf)
 #endif /* HAVE_PCAP_SETDIRECTION */
 #else /* HAVE_PCAP_CREATE */
 	*ebuf = '\0';
+	/*
+	 * If no snapshot length was specified, or a length of 0 was
+	 * specified, default to 256KB.
+	 */
+	if (ndo->ndo_snaplen == 0)
+		ndo->ndo_snaplen = 262144;
 	pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000, ebuf);
 	if (pc == NULL) {
 		/*
@@ -1172,15 +1182,16 @@ int
 main(int argc, char **argv)
 {
 	register int cnt, op, i;
-	bpf_u_int32 localnet =0 , netmask = 0;
+	bpf_u_int32 localnet = 0, netmask = 0;
 	int timezone_offset = 0;
 	register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
+	char *endp;
 	pcap_handler callback;
 	int dlt;
 	const char *dlt_name;
 	struct bpf_program fcode;
 #ifndef _WIN32
-	RETSIGTYPE (*oldhandler)(int);
+	void (*oldhandler)(int);
 #endif
 	struct dump_info dumpinfo;
 	u_char *pcap_userdata;
@@ -1203,6 +1214,7 @@ main(int argc, char **argv)
 	int Oflag = 1;			/* run filter code optimizer */
 	int yflag_dlt = -1;
 	const char *yflag_dlt_name = NULL;
+	int print = 0;
 
 	netdissect_options Ndo;
 	netdissect_options *ndo = &Ndo;
@@ -1215,7 +1227,6 @@ main(int argc, char **argv)
 
 	memset(ndo, 0, sizeof(*ndo));
 	ndo_set_function_pointers(ndo);
-	ndo->ndo_snaplen = DEFAULT_SNAPLEN;
 
 	cnt = -1;
 	device = NULL;
@@ -1276,9 +1287,25 @@ main(int argc, char **argv)
 			break;
 
 		case 'C':
-			Cflag = atoi(optarg) * 1000000;
-			if (Cflag <= 0)
+			errno = 0;
+#ifdef HAVE_PCAP_FTELL64
+			Cflag = strtoint64_t(optarg, &endp, 10);
+#else
+			Cflag = strtol(optarg, &endp, 10);
+#endif
+			if (endp == optarg || *endp != '\0' || errno != 0
+			    || Cflag <= 0)
 				error("invalid file size %s", optarg);
+			/*
+			 * Will multiplying it by 1000000 overflow?
+			 */
+#ifdef HAVE_PCAP_FTELL64
+			if (Cflag > INT64_T_CONSTANT(0x7fffffffffffffffU) / 1000000)
+#else
+			if (Cflag > LONG_MAX / 1000000)
+#endif
+				error("file size %s is too large", optarg);
+			Cflag *= 1000000;
 			break;
 
 		case 'd':
@@ -1445,8 +1472,6 @@ main(int argc, char **argv)
 			if (optarg == end || *end != '\0'
 			    || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN)
 				error("invalid snaplen %s", optarg);
-			else if (ndo->ndo_snaplen == 0)
-				ndo->ndo_snaplen = MAXIMUM_SNAPLEN;
 			break;
 
 		case 'S':
@@ -1582,6 +1607,10 @@ main(int argc, char **argv)
 			break;
 #endif
 
+		case OPTION_PRINT:
+			print = 1;
+			break;
+
 		default:
 			print_usage();
 			exit_tcpdump(1);
@@ -1620,11 +1649,14 @@ main(int argc, char **argv)
 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
 	/*
 	 * If we're printing dissected packets to the standard output
-	 * rather than saving raw packets to a file, and the standard
-	 * output is a terminal, use immediate mode, as the user's
-	 * probably expecting to see packets pop up immediately.
+	 * and the standard output is a terminal, use immediate mode,
+	 * as the user's probably expecting to see packets pop up
+	 * immediately.
+	 *
+	 * XXX - set the timeout to a lower value, instead?  If so,
+	 * what value would be appropriate?
 	 */
-	if (WFileName == NULL && isatty(1))
+	if ((WFileName == NULL || print) && isatty(1))
 		immediate_mode = 1;
 #endif
 
@@ -1724,20 +1756,21 @@ main(int argc, char **argv)
 			 * Find the list of interfaces, and pick
 			 * the first interface.
 			 */
-			if (pcap_findalldevs(&devlist, ebuf) >= 0 &&
-			    devlist != NULL) {
-				device = strdup(devlist->name);
-				pcap_freealldevs(devlist);
-			}
+			if (pcap_findalldevs(&devlist, ebuf) == -1)
+				error("%s", ebuf);
+			if (devlist == NULL)
+				error("no interfaces available for capture");
+			device = strdup(devlist->name);
+			pcap_freealldevs(devlist);
 #else /* HAVE_PCAP_FINDALLDEVS */
 			/*
 			 * Use whatever interface pcap_lookupdev()
 			 * chooses.
 			 */
 			device = pcap_lookupdev(ebuf);
-#endif
 			if (device == NULL)
 				error("%s", ebuf);
+#endif
 		}
 
 		/*
@@ -1784,7 +1817,8 @@ main(int argc, char **argv)
 		}
 
 		/*
-		 * Let user own process after socket has been opened.
+		 * Let user own process after capture device has
+		 * been opened.
 		 */
 #ifndef _WIN32
 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
@@ -1819,7 +1853,11 @@ main(int argc, char **argv)
 		}
 		i = pcap_snapshot(pd);
 		if (ndo->ndo_snaplen < i) {
-			warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
+			if (ndo->ndo_snaplen != 0)
+				warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
+			ndo->ndo_snaplen = i;
+		} else if (ndo->ndo_snaplen > i) {
+			warning("snaplen lowered from %d to %d", ndo->ndo_snaplen, i);
 			ndo->ndo_snaplen = i;
 		}
                 if(ndo->ndo_fflag != 0) {
@@ -2009,8 +2047,18 @@ main(int argc, char **argv)
 			pcap_userdata = (u_char *)&dumpinfo;
 		} else {
 			callback = dump_packet;
-			pcap_userdata = (u_char *)p;
+			dumpinfo.WFileName = WFileName;
+			dumpinfo.pd = pd;
+			dumpinfo.p = p;
+			pcap_userdata = (u_char *)&dumpinfo;
 		}
+		if (print) {
+			dlt = pcap_datalink(pd);
+			ndo->ndo_if_printer = get_if_printer(ndo, dlt);
+			dumpinfo.ndo = ndo;
+		} else
+			dumpinfo.ndo = NULL;
+
 #ifdef HAVE_PCAP_DUMP_FLUSH
 		if (Uflag)
 			pcap_dump_flush(p);
@@ -2031,11 +2079,11 @@ main(int argc, char **argv)
 		(void)setsignal(SIGNAL_REQ_INFO, requestinfo);
 #endif
 
-	if (ndo->ndo_vflag > 0 && WFileName) {
+	if (ndo->ndo_vflag > 0 && WFileName && !print) {
 		/*
-		 * When capturing to a file, "-v" means tcpdump should,
-		 * every 10 seconds, "v"erbosely report the number of
-		 * packets captured.
+		 * When capturing to a file, if "--print" wasn't specified,
+		 *"-v" means tcpdump should, once per second,
+		 * "v"erbosely report the number of packets captured.
 		 */
 #ifdef USE_WIN32_MM_TIMER
 		/* call verbose_stats_dump() each 1000 +/-100msec */
@@ -2203,8 +2251,29 @@ main(int argc, char **argv)
 	exit_tcpdump(status == -1 ? 1 : 0);
 }
 
+/*
+ * Catch a signal.
+ */
+static void
+(*setsignal (int sig, void (*func)(int)))(int)
+{
+#ifdef _WIN32
+	return (signal(sig, func));
+#else
+	struct sigaction old, new;
+
+	memset(&new, 0, sizeof(new));
+	new.sa_handler = func;
+	if (sig == SIGCHLD)
+		new.sa_flags = SA_RESTART;
+	if (sigaction(sig, &new, &old) < 0)
+		return (SIG_ERR);
+	return (old.sa_handler);
+#endif
+}
+
 /* make a clean exit on interrupts */
-static RETSIGTYPE
+static void
 cleanup(int signo _U_)
 {
 #ifdef USE_WIN32_MM_TIMER
@@ -2249,7 +2318,7 @@ cleanup(int signo _U_)
   waiting a child processes to die
  */
 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
-static RETSIGTYPE
+static void
 child_cleanup(int signo _U_)
 {
   wait(NULL);
@@ -2480,7 +2549,17 @@ 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) {
+#ifdef HAVE_PCAP_FTELL64
+		int64_t size = pcap_dump_ftell64(dump_info->p);
+#else
+		/*
+		 * XXX - this only handles a Cflag value > 2^31-1 on
+		 * LP64 platforms; to handle ILP32 (32-bit UN*X and
+		 * Windows) or LLP64 (64-bit Windows) would require
+		 * a version of libpcap with pcap_dump_ftell64().
+		 */
 		long size = pcap_dump_ftell(dump_info->p);
+#endif
 
 		if (size == -1)
 			error("ftell fails on output file");
@@ -2551,6 +2630,9 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s
 		pcap_dump_flush(dump_info->p);
 #endif
 
+	if (dump_info->ndo != NULL)
+		pretty_print_packet(dump_info->ndo, h, sp, packets_captured);
+
 	--infodelay;
 	if (infoprint)
 		info(0);
@@ -2559,16 +2641,23 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s
 static void
 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 {
+	struct dump_info *dump_info;
+
 	++packets_captured;
 
 	++infodelay;
 
-	pcap_dump(user, h, sp);
+	dump_info = (struct dump_info *)user;
+
+	pcap_dump((u_char *)dump_info->p, h, sp);
 #ifdef HAVE_PCAP_DUMP_FLUSH
 	if (Uflag)
-		pcap_dump_flush((pcap_dumper_t *)user);
+		pcap_dump_flush(dump_info->p);
 #endif
 
+	if (dump_info->ndo != NULL)
+		pretty_print_packet(dump_info->ndo, h, sp, packets_captured);
+
 	--infodelay;
 	if (infoprint)
 		info(0);
@@ -2616,7 +2705,7 @@ print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 #endif
 
 #ifdef SIGNAL_REQ_INFO
-RETSIGTYPE requestinfo(int signo _U_)
+void requestinfo(int signo _U_)
 {
 	if (infodelay)
 		++infoprint;
@@ -2625,6 +2714,18 @@ RETSIGTYPE requestinfo(int signo _U_)
 }
 #endif
 
+static void
+print_packets_captured (void)
+{
+	static u_int prev_packets_captured, first = 1;
+
+	if (infodelay == 0 && (first || packets_captured != prev_packets_captured)) {
+		fprintf(stderr, "Got %u\r", packets_captured);
+		first = 0;
+		prev_packets_captured = packets_captured;
+	}
+}
+
 /*
  * Called once each second in verbose mode while dumping to file
  */
@@ -2632,14 +2733,12 @@ RETSIGTYPE requestinfo(int signo _U_)
 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
 				  DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
 {
-	if (infodelay == 0)
-		fprintf(stderr, "Got %u\r", packets_captured);
+	print_packets_captured();
 }
 #elif defined(HAVE_ALARM)
 static void verbose_stats_dump(int sig _U_)
 {
-	if (infodelay == 0)
-		fprintf(stderr, "Got %u\r", packets_captured);
+	print_packets_captured();
 	alarm(1);
 }
 #endif
@@ -2682,6 +2781,9 @@ print_version(void)
 	smi_version_string = nd_smi_version_string();
 	if (smi_version_string != NULL)
 		(void)fprintf (stderr, "SMI-library: %s\n", smi_version_string);
+#ifdef HAVE_DNET_HTOA
+	(void)fprintf(stderr, "libdnet unknown version\n");
+#endif
 
 #if defined(__SANITIZE_ADDRESS__)
 	(void)fprintf (stderr, "Compiled with AddressSanitizer/GCC.\n");
@@ -2703,14 +2805,17 @@ print_usage(void)
 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
 	(void)fprintf(stderr,
 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ] [ --number ]\n");
+	(void)fprintf(stderr,
+"\t\t[ --print ]");
 #ifdef HAVE_PCAP_SETDIRECTION
 	(void)fprintf(stderr,
-"\t\t[ -Q in|out|inout ]\n");
+" [ -Q in|out|inout ]");
 #endif
 	(void)fprintf(stderr,
-"\t\t[ -r file ] [ -s snaplen ] ");
+" [ -r file ] [ -s snaplen ]\n");
 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
-	(void)fprintf(stderr, "[ --time-stamp-precision precision ]\n");
+	(void)fprintf(stderr,
+"\t\t[ --time-stamp-precision precision ]\n");
 	(void)fprintf(stderr,
 "\t\t");
 #endif