2 * Copyright (c) 2006 Paolo Abeni (Italy)
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote
15 * products derived from this software without specific prior written
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 * USB sniffing API implementation for Linux platform
31 * By Paolo Abeni <paolo.abeni@email.it>
32 * Modifications: Kris Katterjohn <katterjohn@gmail.com>
41 #include "pcap-usb-linux.h"
44 #ifdef NEED_STRERROR_H
56 #include <netinet/in.h>
57 #include <sys/ioctl.h>
59 #ifdef HAVE_LINUX_USBDEVICE_FS_H
61 * We might need <linux/compiler.h> to define __user for
62 * <linux/usbdevice_fs.h>.
64 #ifdef HAVE_LINUX_COMPILER_H
65 #include <linux/compiler.h>
66 #endif /* HAVE_LINUX_COMPILER_H */
67 #include <linux/usbdevice_fs.h>
68 #endif /* HAVE_LINUX_USBDEVICE_FS_H */
70 #define USB_IFACE "usbmon"
71 #define USB_TEXT_DIR_OLD "/sys/kernel/debug/usbmon"
72 #define USB_TEXT_DIR "/sys/kernel/debug/usb/usbmon"
73 #define SYS_USB_BUS_DIR "/sys/bus/usb/devices"
74 #define PROC_USB_BUS_DIR "/proc/bus/usb"
75 #define USB_LINE_LEN 4096
77 #if __BYTE_ORDER == __LITTLE_ENDIAN
82 #define htols(s) bswap_16(s)
83 #define htoll(l) bswap_32(l)
84 #define htol64(ll) bswap_64(ll)
87 struct mon_bin_stats {
95 size_t data_len; /* Length of data (can be zero) */
98 struct mon_bin_mfetch {
99 int32_t *offvec; /* Vector of events fetched */
100 int32_t nfetch; /* Number of events to fetch (out: fetched) */
101 int32_t nflush; /* Number of events to flush */
104 #define MON_IOC_MAGIC 0x92
106 #define MON_IOCQ_URB_LEN _IO(MON_IOC_MAGIC, 1)
107 #define MON_IOCX_URB _IOWR(MON_IOC_MAGIC, 2, struct mon_bin_hdr)
108 #define MON_IOCG_STATS _IOR(MON_IOC_MAGIC, 3, struct mon_bin_stats)
109 #define MON_IOCT_RING_SIZE _IO(MON_IOC_MAGIC, 4)
110 #define MON_IOCQ_RING_SIZE _IO(MON_IOC_MAGIC, 5)
111 #define MON_IOCX_GET _IOW(MON_IOC_MAGIC, 6, struct mon_bin_get)
112 #define MON_IOCX_MFETCH _IOWR(MON_IOC_MAGIC, 7, struct mon_bin_mfetch)
113 #define MON_IOCH_MFLUSH _IO(MON_IOC_MAGIC, 8)
115 #define MON_BIN_SETUP 0x1 /* setup hdr is present*/
116 #define MON_BIN_SETUP_ZERO 0x2 /* setup buffer is not available */
117 #define MON_BIN_DATA_ZERO 0x4 /* data buffer is not available */
118 #define MON_BIN_ERROR 0x8
121 * Private data for capturing on Linux USB.
123 struct pcap_usb_linux {
124 u_char *mmapbuf; /* memory-mapped region pointer */
125 size_t mmapbuflen; /* size of region */
130 /* forward declaration */
131 static int usb_activate(pcap_t *);
132 static int usb_stats_linux(pcap_t *, struct pcap_stat *);
133 static int usb_stats_linux_bin(pcap_t *, struct pcap_stat *);
134 static int usb_read_linux(pcap_t *, int , pcap_handler , u_char *);
135 static int usb_read_linux_bin(pcap_t *, int , pcap_handler , u_char *);
136 static int usb_read_linux_mmap(pcap_t *, int , pcap_handler , u_char *);
137 static int usb_inject_linux(pcap_t *, const void *, size_t);
138 static int usb_setdirection_linux(pcap_t *, pcap_direction_t);
139 static void usb_cleanup_linux_mmap(pcap_t *);
141 /* facility to add an USB device to the device list*/
143 usb_dev_add(pcap_if_t** alldevsp, int n, char *err_str)
147 pcap_snprintf(dev_name, 10, USB_IFACE"%d", n);
148 pcap_snprintf(dev_descr, 30, "USB bus number %d", n);
150 if (pcap_add_if(alldevsp, dev_name, 0,
151 dev_descr, err_str) < 0)
157 usb_findalldevs(pcap_if_t **alldevsp, char *err_str)
168 * Do we have a "scan all buses" device?
169 * First, try the binary device.
171 fd = open(LINUX_USB_MON_DEV"0", O_RDONLY, 0);
177 if (pcap_add_if(alldevsp, "usbmon0", 0, "All USB buses",
182 * No binary device; do we have the text device?
184 fd = open(USB_TEXT_DIR"/0t", O_RDONLY, 0);
187 * Not at the new location; try the old location.
189 fd = open(USB_TEXT_DIR_OLD"/0t", O_RDONLY, 0);
196 if (pcap_add_if(alldevsp, "usbmon0", 0, "All USB buses",
203 * Now look for individual USB buses.
205 * First, try scanning sysfs USB bus directory.
207 dir = opendir(SYS_USB_BUS_DIR);
209 while ((ret == 0) && ((data = readdir(dir)) != 0)) {
212 if (strncmp(name, "usb", 3) != 0)
215 if (sscanf(&name[3], "%d", &n) == 0)
218 ret = usb_dev_add(alldevsp, n, err_str);
225 /* That didn't work; try scanning procfs USB bus directory. */
226 dir = opendir(PROC_USB_BUS_DIR);
228 while ((ret == 0) && ((data = readdir(dir)) != 0)) {
232 /* if this file name does not end with a number it's not of our interest */
233 if ((len < 1) || !isdigit(name[--len]))
235 while (isdigit(name[--len]));
236 if (sscanf(&name[len+1], "%d", &n) != 1)
239 ret = usb_dev_add(alldevsp, n, err_str);
246 /* neither of them worked */
251 int usb_mmap(pcap_t* handle)
253 struct pcap_usb_linux *handlep = handle->priv;
254 int len = ioctl(handle->fd, MON_IOCQ_RING_SIZE);
258 handlep->mmapbuflen = len;
259 handlep->mmapbuf = mmap(0, handlep->mmapbuflen, PROT_READ,
260 MAP_SHARED, handle->fd, 0);
261 return handlep->mmapbuf != MAP_FAILED;
264 #ifdef HAVE_LINUX_USBDEVICE_FS_H
266 #define CTRL_TIMEOUT (5*1000) /* milliseconds */
268 #define USB_DIR_IN 0x80
269 #define USB_TYPE_STANDARD 0x00
270 #define USB_RECIP_DEVICE 0x00
272 #define USB_REQ_GET_DESCRIPTOR 6
274 #define USB_DT_DEVICE 1
276 /* probe the descriptors of the devices attached to the bus */
277 /* the descriptors will end up in the captured packet stream */
278 /* and be decoded by external apps like wireshark */
279 /* without these identifying probes packet data can't be fully decoded */
281 probe_devices(int bus)
283 struct usbdevfs_ctrltransfer ctrl;
289 /* scan usb bus directories for device nodes */
290 pcap_snprintf(buf, sizeof(buf), "/dev/bus/usb/%03d", bus);
295 while ((ret >= 0) && ((data = readdir(dir)) != 0)) {
297 char* name = data->d_name;
302 pcap_snprintf(buf, sizeof(buf), "/dev/bus/usb/%03d/%s", bus, data->d_name);
304 fd = open(buf, O_RDWR);
309 * Sigh. Different kernels have different member names
310 * for this structure.
312 #ifdef HAVE_USBDEVFS_CTRLTRANSFER_BREQUESTTYPE
313 ctrl.bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
314 ctrl.bRequest = USB_REQ_GET_DESCRIPTOR;
315 ctrl.wValue = USB_DT_DEVICE << 8;
317 ctrl.wLength = sizeof(buf);
319 ctrl.requesttype = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
320 ctrl.request = USB_REQ_GET_DESCRIPTOR;
321 ctrl.value = USB_DT_DEVICE << 8;
323 ctrl.length = sizeof(buf);
326 ctrl.timeout = CTRL_TIMEOUT;
328 ret = ioctl(fd, USBDEVFS_CONTROL, &ctrl);
334 #endif /* HAVE_LINUX_USBDEVICE_FS_H */
337 usb_create(const char *device, char *ebuf, int *is_ours)
344 /* Does this look like a USB monitoring device? */
345 cp = strrchr(device, '/');
348 /* Does it begin with USB_IFACE? */
349 if (strncmp(cp, USB_IFACE, sizeof USB_IFACE - 1) != 0) {
350 /* Nope, doesn't begin with USB_IFACE */
354 /* Yes - is USB_IFACE followed by a number? */
355 cp += sizeof USB_IFACE - 1;
356 devnum = strtol(cp, &cpend, 10);
357 if (cpend == cp || *cpend != '\0') {
358 /* Not followed by a number. */
363 /* Followed by a non-valid number. */
368 /* OK, it's probably ours. */
371 p = pcap_create_common(ebuf, sizeof (struct pcap_usb_linux));
375 p->activate_op = usb_activate;
380 usb_activate(pcap_t* handle)
382 struct pcap_usb_linux *handlep = handle->priv;
383 char full_path[USB_LINE_LEN];
385 /* Initialize some components of the pcap structure. */
386 handle->bufsize = handle->snapshot;
388 handle->linktype = DLT_USB_LINUX;
390 handle->inject_op = usb_inject_linux;
391 handle->setfilter_op = install_bpf_program; /* no kernel filtering */
392 handle->setdirection_op = usb_setdirection_linux;
393 handle->set_datalink_op = NULL; /* can't change data link type */
394 handle->getnonblock_op = pcap_getnonblock_fd;
395 handle->setnonblock_op = pcap_setnonblock_fd;
397 /*get usb bus index from device name */
398 if (sscanf(handle->opt.device, USB_IFACE"%d", &handlep->bus_index) != 1)
400 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
401 "Can't get USB bus index from %s", handle->opt.device);
405 /*now select the read method: try to open binary interface */
406 pcap_snprintf(full_path, USB_LINE_LEN, LINUX_USB_MON_DEV"%d", handlep->bus_index);
407 handle->fd = open(full_path, O_RDONLY, 0);
410 if (handle->opt.rfmon) {
412 * Monitor mode doesn't apply to USB devices.
415 return PCAP_ERROR_RFMON_NOTSUP;
418 /* binary api is available, try to use fast mmap access */
419 if (usb_mmap(handle)) {
420 handle->linktype = DLT_USB_LINUX_MMAPPED;
421 handle->stats_op = usb_stats_linux_bin;
422 handle->read_op = usb_read_linux_mmap;
423 handle->cleanup_op = usb_cleanup_linux_mmap;
424 #ifdef HAVE_LINUX_USBDEVICE_FS_H
425 probe_devices(handlep->bus_index);
429 * "handle->fd" is a real file, so "select()" and
430 * "poll()" work on it.
432 handle->selectable_fd = handle->fd;
436 /* can't mmap, use plain binary interface access */
437 handle->stats_op = usb_stats_linux_bin;
438 handle->read_op = usb_read_linux_bin;
439 #ifdef HAVE_LINUX_USBDEVICE_FS_H
440 probe_devices(handlep->bus_index);
444 /*Binary interface not available, try open text interface */
445 pcap_snprintf(full_path, USB_LINE_LEN, USB_TEXT_DIR"/%dt", handlep->bus_index);
446 handle->fd = open(full_path, O_RDONLY, 0);
452 * Not found at the new location; try
455 pcap_snprintf(full_path, USB_LINE_LEN, USB_TEXT_DIR_OLD"/%dt", handlep->bus_index);
456 handle->fd = open(full_path, O_RDONLY, 0);
458 if (handle->fd < 0) {
459 /* no more fallback, give it up*/
460 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
461 "Can't open USB bus file %s: %s", full_path, strerror(errno));
466 if (handle->opt.rfmon) {
468 * Monitor mode doesn't apply to USB devices.
471 return PCAP_ERROR_RFMON_NOTSUP;
474 handle->stats_op = usb_stats_linux;
475 handle->read_op = usb_read_linux;
479 * "handle->fd" is a real file, so "select()" and "poll()"
482 handle->selectable_fd = handle->fd;
484 /* for plain binary access and text access we need to allocate the read
486 handle->buffer = malloc(handle->bufsize);
487 if (!handle->buffer) {
488 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
489 "malloc: %s", pcap_strerror(errno));
499 return c < 'A' ? c- '0': ((c<'a') ? c - 'A' + 10: c-'a'+10);
503 * see <linux-kernel-source>/Documentation/usb/usbmon.txt and
504 * <linux-kernel-source>/drivers/usb/mon/mon_text.c for urb string
508 usb_read_linux(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user)
511 * /usr/src/linux/Documentation/usb/usbmon.txt
514 struct pcap_usb_linux *handlep = handle->priv;
516 int tag, cnt, ep_num, dev_addr, dummy, ret, urb_len, data_len;
517 char etype, pipeid1, pipeid2, status[16], urb_tag, line[USB_LINE_LEN];
519 u_char * rawdata = handle->buffer;
520 struct pcap_pkthdr pkth;
521 pcap_usb_header* uhdr = (pcap_usb_header*)handle->buffer;
522 u_char urb_transfer=0;
525 /* ignore interrupt system call errors */
527 ret = read(handle->fd, line, USB_LINE_LEN - 1);
528 if (handle->break_loop)
530 handle->break_loop = 0;
533 } while ((ret == -1) && (errno == EINTR));
537 return 0; /* no data there */
539 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
540 "Can't read from fd %d: %s", handle->fd, strerror(errno));
544 /* read urb header; %n argument may increment return value, but it's
545 * not mandatory, so does not count on it*/
547 ret = sscanf(string, "%x %d %c %c%c:%d:%d %s%n", &tag, ×tamp, &etype,
548 &pipeid1, &pipeid2, &dev_addr, &ep_num, status,
552 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
553 "Can't parse USB bus message '%s', too few tokens (expected 8 got %d)",
558 uhdr->device_address = dev_addr;
559 uhdr->bus_id = handlep->bus_index;
563 /* don't use usbmon provided timestamp, since it have low precision*/
564 if (gettimeofday(&pkth.ts, NULL) < 0)
566 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
567 "Can't get timestamp for message '%s' %d:%s",
568 string, errno, strerror(errno));
571 uhdr->ts_sec = pkth.ts.tv_sec;
572 uhdr->ts_usec = pkth.ts.tv_usec;
574 /* parse endpoint information */
576 urb_transfer = URB_CONTROL;
577 else if (pipeid1 == 'Z')
578 urb_transfer = URB_ISOCHRONOUS;
579 else if (pipeid1 == 'I')
580 urb_transfer = URB_INTERRUPT;
581 else if (pipeid1 == 'B')
582 urb_transfer = URB_BULK;
583 if (pipeid2 == 'i') {
584 ep_num |= URB_TRANSFER_IN;
588 incoming = !incoming;
593 if (handle->direction == PCAP_D_OUT)
597 if (handle->direction == PCAP_D_IN)
599 uhdr->event_type = etype;
600 uhdr->transfer_type = urb_transfer;
601 uhdr->endpoint_number = ep_num;
602 pkth.caplen = sizeof(pcap_usb_header);
603 rawdata += sizeof(pcap_usb_header);
605 /* check if this is a setup packet */
606 ret = sscanf(status, "%d", &dummy);
609 /* this a setup packet, setup data can be filled with underscore if
610 * usbmon has not been able to read them, so we must parse this fields as
612 pcap_usb_setup* shdr;
613 char str1[3], str2[3], str3[5], str4[5], str5[5];
614 ret = sscanf(string, "%s %s %s %s %s%n", str1, str2, str3, str4,
618 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
619 "Can't parse USB bus message '%s', too few tokens (expected 5 got %d)",
625 /* try to convert to corresponding integer */
627 shdr->bmRequestType = strtoul(str1, 0, 16);
628 shdr->bRequest = strtoul(str2, 0, 16);
629 shdr->wValue = htols(strtoul(str3, 0, 16));
630 shdr->wIndex = htols(strtoul(str4, 0, 16));
631 shdr->wLength = htols(strtoul(str5, 0, 16));
633 uhdr->setup_flag = 0;
636 uhdr->setup_flag = 1;
639 ret = sscanf(string, " %d%n", &urb_len, &cnt);
642 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
643 "Can't parse urb length from '%s'", string);
648 /* urb tag is not present if urb length is 0, so we can stop here
650 pkth.len = urb_len+pkth.caplen;
651 uhdr->urb_len = urb_len;
654 if (uhdr->urb_len == 0)
657 /* check for data presence; data is present if and only if urb tag is '=' */
658 if (sscanf(string, " %c", &urb_tag) != 1)
660 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
661 "Can't parse urb tag from '%s'", string);
668 /* skip urb tag and following space */
671 /* if we reach this point we got some urb data*/
674 /* read all urb data; if urb length is greater then the usbmon internal
675 * buffer length used by the kernel to spool the URB, we get only
676 * a partial information.
677 * At least until linux 2.6.17 there is no way to set usbmon intenal buffer
678 * length and default value is 130. */
679 while ((string[0] != 0) && (string[1] != 0) && (pkth.caplen < (bpf_u_int32)handle->snapshot))
681 rawdata[0] = ascii_to_int(string[0]) * 16 + ascii_to_int(string[1]);
684 if (string[0] == ' ')
691 uhdr->data_len = data_len;
692 if (pkth.caplen > (bpf_u_int32)handle->snapshot)
693 pkth.caplen = (bpf_u_int32)handle->snapshot;
695 if (handle->fcode.bf_insns == NULL ||
696 bpf_filter(handle->fcode.bf_insns, handle->buffer,
697 pkth.len, pkth.caplen)) {
698 handlep->packets_read++;
699 callback(user, &pkth, handle->buffer);
702 return 0; /* didn't pass filter */
706 usb_inject_linux(pcap_t *handle, const void *buf, size_t size)
708 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported on "
714 usb_stats_linux(pcap_t *handle, struct pcap_stat *stats)
716 struct pcap_usb_linux *handlep = handle->priv;
717 int dummy, ret, consumed, cnt;
718 char string[USB_LINE_LEN];
719 char token[USB_LINE_LEN];
723 pcap_snprintf(string, USB_LINE_LEN, USB_TEXT_DIR"/%ds", handlep->bus_index);
724 fd = open(string, O_RDONLY, 0);
730 * Not found at the new location; try the old
733 pcap_snprintf(string, USB_LINE_LEN, USB_TEXT_DIR_OLD"/%ds", handlep->bus_index);
734 fd = open(string, O_RDONLY, 0);
737 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
738 "Can't open USB stats file %s: %s",
739 string, strerror(errno));
744 /* read stats line */
746 ret = read(fd, string, USB_LINE_LEN-1);
747 } while ((ret == -1) && (errno == EINTR));
752 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
753 "Can't read stats from fd %d ", fd);
758 /* extract info on dropped urbs */
759 for (consumed=0; consumed < ret; ) {
760 /* from the sscanf man page:
761 * The C standard says: "Execution of a %n directive does
762 * not increment the assignment count returned at the completion
763 * of execution" but the Corrigendum seems to contradict this.
764 * Do not make any assumptions on the effect of %n conversions
765 * on the return value and explicitly check for cnt assignmet*/
769 ntok = sscanf(ptr, "%s%n", token, &cnt);
770 if ((ntok < 1) || (cnt < 0))
774 if (strcmp(token, "nreaders") == 0)
775 ret = sscanf(ptr, "%d", &stats->ps_drop);
777 ret = sscanf(ptr, "%d", &dummy);
784 stats->ps_recv = handlep->packets_read;
785 stats->ps_ifdrop = 0;
790 usb_setdirection_linux(pcap_t *p, pcap_direction_t d)
798 usb_stats_linux_bin(pcap_t *handle, struct pcap_stat *stats)
800 struct pcap_usb_linux *handlep = handle->priv;
802 struct mon_bin_stats st;
803 ret = ioctl(handle->fd, MON_IOCG_STATS, &st);
806 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
807 "Can't read stats from fd %d:%s ", handle->fd, strerror(errno));
811 stats->ps_recv = handlep->packets_read + st.queued;
812 stats->ps_drop = st.dropped;
813 stats->ps_ifdrop = 0;
818 * see <linux-kernel-source>/Documentation/usb/usbmon.txt and
819 * <linux-kernel-source>/drivers/usb/mon/mon_bin.c binary ABI
822 usb_read_linux_bin(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user)
824 struct pcap_usb_linux *handlep = handle->priv;
825 struct mon_bin_get info;
827 struct pcap_pkthdr pkth;
828 u_int clen = handle->snapshot - sizeof(pcap_usb_header);
830 /* the usb header is going to be part of 'packet' data*/
831 info.hdr = (pcap_usb_header*) handle->buffer;
832 info.data = (u_char *)handle->buffer + sizeof(pcap_usb_header);
833 info.data_len = clen;
835 /* ignore interrupt system call errors */
837 ret = ioctl(handle->fd, MON_IOCX_GET, &info);
838 if (handle->break_loop)
840 handle->break_loop = 0;
843 } while ((ret == -1) && (errno == EINTR));
847 return 0; /* no data there */
849 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
850 "Can't read from fd %d: %s", handle->fd, strerror(errno));
854 /* we can get less that than really captured from kernel, depending on
855 * snaplen, so adjust header accordingly */
856 if (info.hdr->data_len < clen)
857 clen = info.hdr->data_len;
858 info.hdr->data_len = clen;
859 pkth.caplen = clen + sizeof(pcap_usb_header);
860 pkth.len = info.hdr->data_len + sizeof(pcap_usb_header);
861 pkth.ts.tv_sec = info.hdr->ts_sec;
862 pkth.ts.tv_usec = info.hdr->ts_usec;
864 if (handle->fcode.bf_insns == NULL ||
865 bpf_filter(handle->fcode.bf_insns, handle->buffer,
866 pkth.len, pkth.caplen)) {
867 handlep->packets_read++;
868 callback(user, &pkth, handle->buffer);
872 return 0; /* didn't pass filter */
876 * see <linux-kernel-source>/Documentation/usb/usbmon.txt and
877 * <linux-kernel-source>/drivers/usb/mon/mon_bin.c binary ABI
881 usb_read_linux_mmap(pcap_t *handle, int max_packets, pcap_handler callback, u_char *user)
883 struct pcap_usb_linux *handlep = handle->priv;
884 struct mon_bin_mfetch fetch;
885 int32_t vec[VEC_SIZE];
886 struct pcap_pkthdr pkth;
887 pcap_usb_header* hdr;
890 u_int clen, max_clen;
892 max_clen = handle->snapshot - sizeof(pcap_usb_header);
896 int limit = max_packets - packets;
899 if (limit > VEC_SIZE)
902 /* try to fetch as many events as possible*/
904 fetch.nfetch = limit;
905 fetch.nflush = nflush;
906 /* ignore interrupt system call errors */
908 ret = ioctl(handle->fd, MON_IOCX_MFETCH, &fetch);
909 if (handle->break_loop)
911 handle->break_loop = 0;
914 } while ((ret == -1) && (errno == EINTR));
918 return 0; /* no data there */
920 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
921 "Can't mfetch fd %d: %s", handle->fd, strerror(errno));
925 /* keep track of processed events, we will flush them later */
926 nflush = fetch.nfetch;
927 for (i=0; i<fetch.nfetch; ++i) {
929 hdr = (pcap_usb_header*) &handlep->mmapbuf[vec[i]];
930 if (hdr->event_type == '@')
933 /* we can get less that than really captured from kernel, depending on
934 * snaplen, so adjust header accordingly */
936 if (hdr->data_len < clen)
937 clen = hdr->data_len;
939 /* get packet info from header*/
940 pkth.caplen = clen + sizeof(pcap_usb_header_mmapped);
941 pkth.len = hdr->data_len + sizeof(pcap_usb_header_mmapped);
942 pkth.ts.tv_sec = hdr->ts_sec;
943 pkth.ts.tv_usec = hdr->ts_usec;
945 if (handle->fcode.bf_insns == NULL ||
946 bpf_filter(handle->fcode.bf_insns, (u_char*) hdr,
947 pkth.len, pkth.caplen)) {
948 handlep->packets_read++;
949 callback(user, &pkth, (u_char*) hdr);
954 /* with max_packets specifying "unlimited" we stop afer the first chunk*/
955 if (PACKET_COUNT_IS_UNLIMITED(max_packets) || (packets == max_packets))
959 /* flush pending events*/
960 if (ioctl(handle->fd, MON_IOCH_MFLUSH, nflush) == -1) {
961 pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE,
962 "Can't mflush fd %d: %s", handle->fd, strerror(errno));
969 usb_cleanup_linux_mmap(pcap_t* handle)
971 struct pcap_usb_linux *handlep = handle->priv;
973 /* if we have a memory-mapped buffer, unmap it */
974 if (handlep->mmapbuf != NULL) {
975 munmap(handlep->mmapbuf, handlep->mmapbuflen);
976 handlep->mmapbuf = NULL;
978 pcap_cleanup_live_common(handle);