1 /* 2 * Copyright (c) 2014 Michal Labedzki for Tieto Corporation 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 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 16 * permission. 17 * 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. 29 * 30 */ 31 32 #ifdef HAVE_CONFIG_H 33 #include "config.h" 34 #endif 35 36 #include <errno.h> 37 #include <stdlib.h> 38 #include <string.h> 39 40 #include <bluetooth/bluetooth.h> 41 #include <bluetooth/hci.h> 42 #include <bluetooth/mgmt.h> 43 44 #include "pcap/bluetooth.h" 45 #include "pcap-int.h" 46 47 #include "pcap-bt-monitor-linux.h" 48 49 #define BT_CONTROL_SIZE 32 50 #define INTERFACE_NAME "bluetooth-monitor" 51 52 int 53 bt_monitor_findalldevs(pcap_if_t **alldevsp, char *err_str) 54 { 55 int ret = 0; 56 57 if (pcap_add_if(alldevsp, INTERFACE_NAME, 0, 58 "Bluetooth Linux Monitor", err_str) < 0) 59 { 60 ret = -1; 61 } 62 63 return ret; 64 } 65 66 static int 67 bt_monitor_read(pcap_t *handle, int max_packets _U_, pcap_handler callback, u_char *user) 68 { 69 struct cmsghdr *cmsg; 70 struct msghdr msg; 71 struct iovec iv[2]; 72 ssize_t ret; 73 struct pcap_pkthdr pkth; 74 pcap_bluetooth_linux_monitor_header *bthdr; 75 struct mgmt_hdr hdr; 76 77 bthdr = (pcap_bluetooth_linux_monitor_header*) &handle->buffer[handle->offset]; 78 79 iv[0].iov_base = &hdr; 80 iv[0].iov_len = MGMT_HDR_SIZE; 81 iv[1].iov_base = &handle->buffer[handle->offset + sizeof(pcap_bluetooth_linux_monitor_header)]; 82 iv[1].iov_len = handle->snapshot; 83 84 memset(&pkth.ts, 0, sizeof(pkth.ts)); 85 memset(&msg, 0, sizeof(msg)); 86 msg.msg_iov = iv; 87 msg.msg_iovlen = 2; 88 msg.msg_control = handle->buffer; 89 msg.msg_controllen = handle->offset; 90 91 do { 92 ret = recvmsg(handle->fd, &msg, 0); 93 if (handle->break_loop) 94 { 95 handle->break_loop = 0; 96 return -2; 97 } 98 } while ((ret == -1) && (errno == EINTR)); 99 100 if (ret < 0) { 101 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 102 "Can't receive packet: %s", strerror(errno)); 103 return -1; 104 } 105 106 pkth.caplen = ret - MGMT_HDR_SIZE + sizeof(pcap_bluetooth_linux_monitor_header); 107 pkth.len = pkth.caplen; 108 109 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = CMSG_NXTHDR(&msg, cmsg)) { 110 if (cmsg->cmsg_level != SOL_SOCKET) continue; 111 112 if (cmsg->cmsg_type == SCM_TIMESTAMP) { 113 memcpy(&pkth.ts, CMSG_DATA(cmsg), sizeof(pkth.ts)); 114 } 115 } 116 117 bthdr->adapter_id = htons(hdr.index); 118 bthdr->opcode = htons(hdr.opcode); 119 120 if (handle->fcode.bf_insns == NULL || 121 bpf_filter(handle->fcode.bf_insns, &handle->buffer[handle->offset], 122 pkth.len, pkth.caplen)) { 123 callback(user, &pkth, &handle->buffer[handle->offset]); 124 return 1; 125 } 126 return 0; /* didn't pass filter */ 127 } 128 129 static int 130 bt_monitor_inject(pcap_t *handle, const void *buf _U_, size_t size _U_) 131 { 132 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "inject not supported yet"); 133 return -1; 134 } 135 136 static int 137 bt_monitor_setdirection(pcap_t *p, pcap_direction_t d) 138 { 139 p->direction = d; 140 return 0; 141 } 142 143 static int 144 bt_monitor_stats(pcap_t *handle _U_, struct pcap_stat *stats) 145 { 146 stats->ps_recv = 0; 147 stats->ps_drop = 0; 148 stats->ps_ifdrop = 0; 149 150 return 0; 151 } 152 153 static int 154 bt_monitor_activate(pcap_t* handle) 155 { 156 struct sockaddr_hci addr; 157 int err = PCAP_ERROR; 158 int opt; 159 160 if (handle->opt.rfmon) { 161 /* monitor mode doesn't apply here */ 162 return PCAP_ERROR_RFMON_NOTSUP; 163 } 164 165 handle->bufsize = handle->snapshot + BT_CONTROL_SIZE + sizeof(pcap_bluetooth_linux_monitor_header); 166 handle->offset = BT_CONTROL_SIZE; 167 handle->linktype = DLT_BLUETOOTH_LINUX_MONITOR; 168 169 handle->read_op = bt_monitor_read; 170 handle->inject_op = bt_monitor_inject; 171 handle->setfilter_op = install_bpf_program; /* no kernel filtering */ 172 handle->setdirection_op = bt_monitor_setdirection; 173 handle->set_datalink_op = NULL; /* can't change data link type */ 174 handle->getnonblock_op = pcap_getnonblock_fd; 175 handle->setnonblock_op = pcap_setnonblock_fd; 176 handle->stats_op = bt_monitor_stats; 177 178 handle->fd = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI); 179 if (handle->fd < 0) { 180 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 181 "Can't create raw socket: %s", strerror(errno)); 182 return PCAP_ERROR; 183 } 184 185 handle->buffer = malloc(handle->bufsize); 186 if (!handle->buffer) { 187 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't allocate dump buffer: %s", 188 pcap_strerror(errno)); 189 goto close_fail; 190 } 191 192 /* Bind socket to the HCI device */ 193 addr.hci_family = AF_BLUETOOTH; 194 addr.hci_dev = HCI_DEV_NONE; 195 addr.hci_channel = HCI_CHANNEL_MONITOR; 196 197 if (bind(handle->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { 198 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 199 "Can't attach to interface: %s", strerror(errno)); 200 goto close_fail; 201 } 202 203 opt = 1; 204 if (setsockopt(handle->fd, SOL_SOCKET, SO_TIMESTAMP, &opt, sizeof(opt)) < 0) { 205 snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, 206 "Can't enable time stamp: %s", strerror(errno)); 207 goto close_fail; 208 } 209 210 handle->selectable_fd = handle->fd; 211 212 return 0; 213 214 close_fail: 215 pcap_cleanup_live_common(handle); 216 return err; 217 } 218 219 pcap_t * 220 bt_monitor_create(const char *device, char *ebuf, int *is_ours) 221 { 222 pcap_t *p; 223 const char *cp; 224 225 cp = strrchr(device, '/'); 226 if (cp == NULL) 227 cp = device; 228 229 if (strcmp(cp, INTERFACE_NAME) != 0) { 230 *is_ours = 0; 231 return NULL; 232 } 233 234 *is_ours = 1; 235 p = pcap_create_common(device, ebuf, 0); 236 if (p == NULL) 237 return NULL; 238 239 p->activate_op = bt_monitor_activate; 240 241 return p; 242 } 243
