X-Git-Url: https://git.tcpdump.org/tcpdump/blobdiff_plain/3eab64d3214c1c7aa5aea9ff0f5313b8f361bd5c..9beea81f673bd6267a536d9132ca06a3d20a0235:/tcpdump.c

diff --git a/tcpdump.c b/tcpdump.c
index 3786b1da..36c73259 100644
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -34,6 +34,9 @@
  */
 
 #include <config.h>
+#ifndef TCPDUMP_CONFIG_H_
+#error "The included config.h header is not from the tcpdump build."
+#endif
 
 #include "netdissect-stdinc.h"
 
@@ -141,7 +144,6 @@ The Regents of the University of California.  All rights reserved.\n";
 #include "netdissect.h"
 #include "interface.h"
 #include "addrtoname.h"
-#include "pcap-missing.h"
 #include "ascii_strcasecmp.h"
 
 #include "print.h"
@@ -207,7 +209,7 @@ static int timeout = 1000;		/* default timeout = 1000 ms = 1 s */
 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;
@@ -1346,6 +1348,11 @@ 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) {
@@ -2055,8 +2062,8 @@ main(int argc, char **argv)
 			break;
 
 		case OPTION_SKIP:
-			packets_skipped = parse_u_int("packet skip count",
-			    optarg, NULL, 1, UINT_MAX, 0);
+			packets_to_skip = parse_u_int("packet skip count",
+			    optarg, NULL, 0, INT_MAX, 0);
 			break;
 
 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
@@ -2097,6 +2104,12 @@ main(int argc, char **argv)
 	if (ndo->ndo_xflag && ndo->ndo_Xflag)
 		warning("-x[x] and -X[X] are mutually exclusive. -x[x] ignored.");
 
+	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
@@ -2364,7 +2377,11 @@ 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);
@@ -2379,6 +2396,7 @@ 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
@@ -2693,7 +2711,7 @@ 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) {
 			/*
@@ -2782,7 +2800,11 @@ 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));
 				}
 
@@ -3184,7 +3206,7 @@ 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;
 
 	/*
@@ -3316,7 +3338,7 @@ 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);
@@ -3338,7 +3360,7 @@ 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;