}
#endif
-#define COMMAND_OPTIONS "Li:w:y:"
+static long
+parse_interface_number(const char *device)
+{
+ const char *p;
+ long devnum;
+ char *end;
+
+ /*
+ * Search for a colon, terminating any scheme at the beginning
+ * of the device.
+ */
+ p = strchr(device, ':');
+ if (p != NULL) {
+ /*
+ * We found it. Is it followed by "//"?
+ */
+ p++; /* skip the : */
+ if (strncmp(p, "//", 2) == 0) {
+ /*
+ * Yes. Search for the next /, at the end of the
+ * authority part of the URL.
+ */
+ p += 2; /* skip the // */
+ p = strchr(p, '/');
+ if (p != NULL) {
+ /*
+ * OK, past the / is the path.
+ */
+ device = p + 1;
+ }
+ }
+ }
+ devnum = strtol(device, &end, 10);
+ if (device != end && *end == '\0') {
+ /*
+ * It's all-numeric, but is it a valid number?
+ */
+ if (devnum <= 0) {
+ /*
+ * No, it's not an ordinal.
+ */
+ error("Invalid adapter index");
+ }
+ return (devnum);
+ } else {
+ /*
+ * It's not all-numeric; return -1, so our caller
+ * knows that.
+ */
+ return (-1);
+ }
+}
+
+static char *
+find_interface_by_number(long devnum)
+{
+ pcap_if_t *dev, *devlist;
+ long i;
+ char ebuf[PCAP_ERRBUF_SIZE];
+ char *device;
+ int status;
+
+ status = pcap_findalldevs(&devlist, ebuf);
+ if (status < 0)
+ error("%s", ebuf);
+ /*
+ * Look for the devnum-th entry in the list of devices (1-based).
+ */
+ for (i = 0, dev = devlist; i < devnum-1 && dev != NULL;
+ i++, dev = dev->next)
+ ;
+ if (dev == NULL)
+ error("Invalid adapter index");
+ device = strdup(dev->name);
+ pcap_freealldevs(devlist);
+ return (device);
+}
+
+static pcap_t *
+open_interface(const char *device, int snaplen_set, int snaplen, char *ebuf)
+{
+ pcap_t *pc;
+ int status;
+ char *cp;
+
+ pc = pcap_create(device, ebuf);
+ if (pc == NULL) {
+ /*
+ * If this failed with "No such device", that means
+ * the interface doesn't exist; return NULL, so that
+ * the caller can see whether the device name is
+ * actually an interface index.
+ */
+ if (strstr(ebuf, "No such device") != NULL)
+ return (NULL);
+ error("%s", ebuf);
+ }
+ if (snaplen_set) {
+ status = pcap_set_snaplen(pc, snaplen);
+ if (status != 0)
+ error("%s: pcap_set_snaplen failed: %s",
+ device, pcap_statustostr(status));
+ }
+ status = pcap_set_timeout(pc, 100);
+ if (status != 0)
+ error("%s: pcap_set_timeout failed: %s",
+ device, pcap_statustostr(status));
+ status = pcap_activate(pc);
+ if (status < 0) {
+ /*
+ * pcap_activate() failed.
+ */
+ cp = pcap_geterr(pc);
+ if (status == PCAP_ERROR)
+ error("%s", cp);
+ else if (status == PCAP_ERROR_NO_SUCH_DEVICE) {
+ /*
+ * Return an error for our caller to handle.
+ */
+ snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s\n(%s)",
+ device, pcap_statustostr(status), cp);
+ } else if (status == PCAP_ERROR_PERM_DENIED && *cp != '\0')
+ error("%s: %s\n(%s)", device,
+ pcap_statustostr(status), cp);
+ else
+ error("%s: %s", device,
+ pcap_statustostr(status));
+ pcap_close(pc);
+ return (NULL);
+ } else if (status > 0) {
+ /*
+ * pcap_activate() succeeded, but it's warning us
+ * of a problem it had.
+ */
+ cp = pcap_geterr(pc);
+ if (status == PCAP_WARNING)
+ warning("%s", cp);
+ else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
+ *cp != '\0')
+ warning("%s: %s\n(%s)", device,
+ pcap_statustostr(status), cp);
+ else
+ warning("%s: %s", device,
+ pcap_statustostr(status));
+ }
+ return (pc);
+}
+
+#define COMMAND_OPTIONS "DLi:s:w:y:"
int
main(int argc, char **argv)
{
- register int op;
- register char *cp, *cmdbuf, *device, *savefile = NULL;
+ int op;
+ char *cp, *cmdbuf = NULL, *device, *end, *savefile = NULL;
+ int snaplen = 0;
+ int snaplen_set = 0;
pcap_if_t *devlist;
+ long devnum;
+ int show_interfaces = 0;
int show_dlt_types = 0;
int ndlts;
int *dlts;
while ((op = getopt(argc, argv, COMMAND_OPTIONS)) != -1) {
switch (op) {
+ case 'D':
+ show_interfaces = 1;
+ break;
+
case 'L':
show_dlt_types = 1;
break;
device = optarg;
break;
+ case 's':
+ snaplen = (int)strtol(optarg, &end, 0);
+ if (optarg == end || *end != '\0' || snaplen < 0)
+ error("invalid snaplen %s (must be >= 0)",
+ optarg);
+ snaplen_set = 1;
+ break;
+
case 'w':
savefile = optarg;
break;
}
}
+ if (show_interfaces) {
+ pcap_if_t *dev;
+ int i;
+
+ if (pcap_findalldevs(&devlist, ebuf) < 0)
+ error("%s", ebuf);
+ for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
+ printf("%d.%s", i+1, dev->name);
+ if (dev->description != NULL)
+ printf(" (%s)", dev->description);
+ printf("\n");
+ }
+ pcap_freealldevs(devlist);
+ return (0);
+ }
+
if (device == NULL) {
if (pcap_findalldevs(&devlist, ebuf) == -1)
error("%s", ebuf);
*ebuf = '\0';
- pd = pcap_create(device, ebuf);
- if (pd == NULL)
- error("%s", ebuf);
- status = pcap_set_snaplen(pd, 262144);
- if (status != 0)
- error("%s: pcap_set_snaplen failed: %s",
- device, pcap_statustostr(status));
- status = pcap_set_timeout(pd, 100);
- if (status != 0)
- error("%s: pcap_set_timeout failed: %s",
- device, pcap_statustostr(status));
- status = pcap_activate(pd);
- if (status < 0) {
+ pd = open_interface(device, snaplen_set, snaplen, ebuf);
+ if (pd == NULL) {
/*
- * pcap_activate() failed.
+ * That failed because the interface couldn't be found.
+ *
+ * If we can get a list of interfaces, and the interface name
+ * is purely numeric, try to use it as a 1-based index
+ * in the list of interfaces.
*/
- error("%s: %s\n(%s)", device,
- pcap_statustostr(status), pcap_geterr(pd));
- } else if (status > 0) {
+ devnum = parse_interface_number(device);
+ if (devnum == -1) {
+ /*
+ * It's not a number; just report
+ * the open error and fail.
+ */
+ error("%s", ebuf);
+ }
+
/*
- * pcap_activate() succeeded, but it's warning us
- * of a problem it had.
+ * OK, it's a number; try to find the
+ * interface with that index, and try
+ * to open it.
+ *
+ * find_interface_by_number() exits if it
+ * couldn't be found.
*/
- warning("%s: %s\n(%s)", device,
- pcap_statustostr(status), pcap_geterr(pd));
+ device = find_interface_by_number(devnum);
+ pd = open_interface(device, snaplen_set, snaplen, ebuf);
+ if (pd == NULL)
+ error("%s", ebuf);
}
+
if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
localnet = 0;
netmask = 0;
error("%s: %s", device, pcap_geterr(pd));
}
- cmdbuf = copy_argv(&argv[optind]);
+ /*
+ * Don't set a filter unless we were given one on the
+ * command line; if capturing doesn't work, or doesn't
+ * use the snapshot length, without a filter, that's
+ * a bug.
+ */
+ if (optind < argc) {
+ cmdbuf = copy_argv(&argv[optind]);
- if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
- error("%s", pcap_geterr(pd));
+ if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)
+ error("%s", pcap_geterr(pd));
- if (pcap_setfilter(pd, &fcode) < 0)
- error("%s", pcap_geterr(pd));
+ if (pcap_setfilter(pd, &fcode) < 0)
+ error("%s", pcap_geterr(pd));
+ }
pdd = pcap_dump_open(pd, savefile);
if (pdd == NULL)
if (status != 0) {
printf("%d packets seen\n", status);
struct pcap_stat ps;
- pcap_stats(pd, &ps);
- printf("%d ps_recv, %d ps_drop, %d ps_ifdrop\n",
- ps.ps_recv, ps.ps_drop, ps.ps_ifdrop);
+ if (pcap_stats(pd, &ps) < 0) {
+ (void)fprintf(stderr, "pcap_stats: %s\n",
+ pcap_geterr(pd));
+ } else {
+ printf("%d ps_recv, %d ps_drop, %d ps_ifdrop\n",
+ ps.ps_recv, ps.ps_drop, ps.ps_ifdrop);
+ }
}
}
if (status == -2) {
program_name, pcap_geterr(pd));
}
pcap_close(pd);
- pcap_freecode(&fcode);
- free(cmdbuf);
+ if (cmdbuf != NULL) {
+ pcap_freecode(&fcode);
+ free(cmdbuf);
+ }
exit(status == -1 ? 1 : 0);
}
static void
usage(void)
{
- (void)fprintf(stderr, "Usage: %s -L [ -i interface ] [ -w file ] [ -y dlt ] [expression]\n",
+ (void)fprintf(stderr, "Usage: %s -D -L [ -i interface ] [ -s snaplen ] [ -w file ] [ -y dlt ] [expression]\n",
program_name);
exit(1);
}
projects / libpcap / blobdiff