blob: c222c100edb23f86cda3e93265a5451a72cafb0e [file] [log] [blame]
/*
* Copyright (c) 2014 Michal Labedzki for Tieto Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <errno.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <bluetooth/bluetooth.h>
#include <bluetooth/hci.h>
#include "pcap/bluetooth.h"
#include "pcap-int.h"
#include "pcap-bt-monitor-linux.h"
#define BT_CONTROL_SIZE 32
#define INTERFACE_NAME "bluetooth-monitor"
/*
* Fields and alignment must match the declaration in the Linux kernel 3.4+.
* See struct hci_mon_hdr in include/net/bluetooth/hci_mon.h.
*/
struct hci_mon_hdr {
uint16_t opcode;
uint16_t index;
uint16_t len;
} __attribute__((packed));
int
bt_monitor_findalldevs(pcap_if_list_t *devlistp, char *err_str)
{
int ret = 0;
/*
* Bluetooth is a wireless technology.
*
* This is a device to monitor all Bluetooth interfaces, so
* there's no notion of "connected" or "disconnected", any
* more than there's a notion of "connected" or "disconnected"
* for the "any" device.
*/
if (add_dev(devlistp, INTERFACE_NAME,
PCAP_IF_WIRELESS|PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE,
"Bluetooth Linux Monitor", err_str) == NULL)
{
ret = -1;
}
return ret;
}
static int
bt_monitor_read(pcap_t *handle, int max_packets _U_, pcap_handler callback, u_char *user)
{
struct cmsghdr *cmsg;
struct msghdr msg;
struct iovec iv[2];
ssize_t ret;
struct pcap_pkthdr pkth;
pcap_bluetooth_linux_monitor_header *bthdr;
u_char *pktd;
struct hci_mon_hdr hdr;
pktd = (u_char *)handle->buffer + BT_CONTROL_SIZE;
bthdr = (pcap_bluetooth_linux_monitor_header*)(void *)pktd;
iv[0].iov_base = &hdr;
iv[0].iov_len = sizeof(hdr);
iv[1].iov_base = pktd + sizeof(pcap_bluetooth_linux_monitor_header);
iv[1].iov_len = handle->snapshot;
memset(&pkth.ts, 0, sizeof(pkth.ts));
memset(&msg, 0, sizeof(msg));
msg.msg_iov = iv;
msg.msg_iovlen = 2;
msg.msg_control = handle->buffer;
msg.msg_controllen = BT_CONTROL_SIZE;
do {
ret = recvmsg(handle->fd, &msg, 0);
if (handle->break_loop)
{
handle->break_loop = 0;
return -2;
}
} while ((ret == -1) && (errno == EINTR));
if (ret < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't receive packet");
return -1;
}
pkth.caplen = ret - sizeof(hdr) + sizeof(pcap_bluetooth_linux_monitor_header);
pkth.len = pkth.caplen;
for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = CMSG_NXTHDR(&msg, cmsg)) {
if (cmsg->cmsg_level != SOL_SOCKET) continue;
if (cmsg->cmsg_type == SCM_TIMESTAMP) {
memcpy(&pkth.ts, CMSG_DATA(cmsg), sizeof(pkth.ts));
}
}
bthdr->adapter_id = htons(hdr.index);
bthdr->opcode = htons(hdr.opcode);
if (handle->fcode.bf_insns == NULL ||
bpf_filter(handle->fcode.bf_insns, pktd, pkth.len, pkth.caplen)) {
callback(user, &pkth, pktd);
return 1;
}
return 0; /* didn't pass filter */
}
static int
bt_monitor_inject(pcap_t *handle, const void *buf _U_, size_t size _U_)
{
pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported yet");
return -1;
}
static int
bt_monitor_setdirection(pcap_t *p, pcap_direction_t d)
{
p->direction = d;
return 0;
}
static int
bt_monitor_stats(pcap_t *handle _U_, struct pcap_stat *stats)
{
stats->ps_recv = 0;
stats->ps_drop = 0;
stats->ps_ifdrop = 0;
return 0;
}
static int
bt_monitor_activate(pcap_t* handle)
{
struct sockaddr_hci addr;
int err = PCAP_ERROR;
int opt;
if (handle->opt.rfmon) {
/* monitor mode doesn't apply here */
return PCAP_ERROR_RFMON_NOTSUP;
}
/*
* Turn a negative snapshot value (invalid), a snapshot value of
* 0 (unspecified), or a value bigger than the normal maximum
* value, into the maximum allowed value.
*
* If some application really *needs* a bigger snapshot
* length, we should just increase MAXIMUM_SNAPLEN.
*/
if (handle->snapshot <= 0 || handle->snapshot > MAXIMUM_SNAPLEN)
handle->snapshot = MAXIMUM_SNAPLEN;
handle->bufsize = BT_CONTROL_SIZE + sizeof(pcap_bluetooth_linux_monitor_header) + handle->snapshot;
handle->linktype = DLT_BLUETOOTH_LINUX_MONITOR;
handle->read_op = bt_monitor_read;
handle->inject_op = bt_monitor_inject;
handle->setfilter_op = install_bpf_program; /* no kernel filtering */
handle->setdirection_op = bt_monitor_setdirection;
handle->set_datalink_op = NULL; /* can't change data link type */
handle->getnonblock_op = pcap_getnonblock_fd;
handle->setnonblock_op = pcap_setnonblock_fd;
handle->stats_op = bt_monitor_stats;
handle->fd = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
if (handle->fd < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't create raw socket");
return PCAP_ERROR;
}
handle->buffer = malloc(handle->bufsize);
if (!handle->buffer) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't allocate dump buffer");
goto close_fail;
}
/* Bind socket to the HCI device */
addr.hci_family = AF_BLUETOOTH;
addr.hci_dev = HCI_DEV_NONE;
addr.hci_channel = HCI_CHANNEL_MONITOR;
if (bind(handle->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't attach to interface");
goto close_fail;
}
opt = 1;
if (setsockopt(handle->fd, SOL_SOCKET, SO_TIMESTAMP, &opt, sizeof(opt)) < 0) {
pcap_fmt_errmsg_for_errno(handle->errbuf, PCAP_ERRBUF_SIZE,
errno, "Can't enable time stamp");
goto close_fail;
}
handle->selectable_fd = handle->fd;
return 0;
close_fail:
pcap_cleanup_live_common(handle);
return err;
}
pcap_t *
bt_monitor_create(const char *device, char *ebuf, int *is_ours)
{
pcap_t *p;
const char *cp;
cp = strrchr(device, '/');
if (cp == NULL)
cp = device;
if (strcmp(cp, INTERFACE_NAME) != 0) {
*is_ours = 0;
return NULL;
}
*is_ours = 1;
p = pcap_create_common(ebuf, 0);
if (p == NULL)
return NULL;
p->activate_op = bt_monitor_activate;
return p;
}