1 /* 2 * rfcomm_pppd.c 3 */ 4 5 /*- 6 * Copyright (c) 2001-2008 Maksim Yevmenkin <m_evmenkin@yahoo.com> 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * $Id: rfcomm_pppd.c,v 1.5 2003/09/07 18:32:11 max Exp $ 31 * $FreeBSD$ 32 */ 33 #define L2CAP_SOCKET_CHECKED 34 #include <bluetooth.h> 35 #include <ctype.h> 36 #include <err.h> 37 #include <errno.h> 38 #include <fcntl.h> 39 #include <sdp.h> 40 #include <signal.h> 41 #include <stdarg.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <syslog.h> 46 #include <unistd.h> 47 48 #define RFCOMM_PPPD "rfcomm_pppd" 49 50 int rfcomm_channel_lookup (bdaddr_t const *local, 51 bdaddr_t const *remote, 52 int service, int *channel, int *error); 53 54 static void exec_ppp (int s, char *unit, char *label); 55 static void sighandler (int s); 56 static void usage (void); 57 58 static int done; 59 60 /* Main */ 61 int 62 main(int argc, char *argv[]) 63 { 64 struct sockaddr_rfcomm sock_addr; 65 char *label = NULL, *unit = NULL, *ep = NULL; 66 bdaddr_t addr; 67 int s, channel, detach, server, service, 68 regdun, regsp; 69 pid_t pid; 70 71 memcpy(&addr, NG_HCI_BDADDR_ANY, sizeof(addr)); 72 channel = 0; 73 detach = 1; 74 server = 0; 75 service = 0; 76 regdun = 0; 77 regsp = 0; 78 79 /* Parse command line arguments */ 80 while ((s = getopt(argc, argv, "a:cC:dDhl:sSu:")) != -1) { 81 switch (s) { 82 case 'a': /* BDADDR */ 83 if (!bt_aton(optarg, &addr)) { 84 struct hostent *he = NULL; 85 86 if ((he = bt_gethostbyname(optarg)) == NULL) 87 errx(1, "%s: %s", optarg, hstrerror(h_errno)); 88 89 memcpy(&addr, he->h_addr, sizeof(addr)); 90 } 91 break; 92 93 case 'c': /* client */ 94 server = 0; 95 break; 96 97 case 'C': /* RFCOMM channel */ 98 channel = strtoul(optarg, &ep, 10); 99 if (*ep != '\0') { 100 channel = 0; 101 switch (tolower(optarg[0])) { 102 case 'd': /* DialUp Networking */ 103 service = SDP_SERVICE_CLASS_DIALUP_NETWORKING; 104 break; 105 106 case 'l': /* LAN Access Using PPP */ 107 service = SDP_SERVICE_CLASS_LAN_ACCESS_USING_PPP; 108 break; 109 } 110 } 111 break; 112 113 case 'd': /* do not detach */ 114 detach = 0; 115 break; 116 117 case 'D': /* Register DUN service as well as LAN service */ 118 regdun = 1; 119 break; 120 121 case 'l': /* PPP label */ 122 label = optarg; 123 break; 124 125 case 's': /* server */ 126 server = 1; 127 break; 128 129 case 'S': /* Register SP service as well as LAN service */ 130 regsp = 1; 131 break; 132 133 case 'u': /* PPP -unit option */ 134 strtoul(optarg, &ep, 10); 135 if (*ep != '\0') 136 usage(); 137 /* NOT REACHED */ 138 139 unit = optarg; 140 break; 141 142 case 'h': 143 default: 144 usage(); 145 /* NOT REACHED */ 146 } 147 } 148 149 /* Check if we got everything we wanted */ 150 if (label == NULL) 151 errx(1, "Must specify PPP label"); 152 153 if (!server) { 154 if (memcmp(&addr, NG_HCI_BDADDR_ANY, sizeof(addr)) == 0) 155 errx(1, "Must specify server BD_ADDR"); 156 157 /* Check channel, if was not set then obtain it via SDP */ 158 if (channel == 0 && service != 0) 159 if (rfcomm_channel_lookup(NULL, &addr, service, 160 &channel, &s) != 0) 161 errc(1, s, "Could not obtain RFCOMM channel"); 162 } 163 164 if (channel <= 0 || channel > 30) 165 errx(1, "Invalid RFCOMM channel number %d", channel); 166 167 openlog(RFCOMM_PPPD, LOG_PID | LOG_PERROR | LOG_NDELAY, LOG_USER); 168 169 if (detach && daemon(0, 0) < 0) { 170 syslog(LOG_ERR, "Could not daemon(0, 0). %s (%d)", 171 strerror(errno), errno); 172 exit(1); 173 } 174 175 s = socket(PF_BLUETOOTH, SOCK_STREAM, BLUETOOTH_PROTO_RFCOMM); 176 if (s < 0) { 177 syslog(LOG_ERR, "Could not create socket. %s (%d)", 178 strerror(errno), errno); 179 exit(1); 180 } 181 182 if (server) { 183 struct sigaction sa; 184 void *ss = NULL; 185 sdp_lan_profile_t lan; 186 187 /* Install signal handler */ 188 memset(&sa, 0, sizeof(sa)); 189 sa.sa_handler = sighandler; 190 191 if (sigaction(SIGTERM, &sa, NULL) < 0) { 192 syslog(LOG_ERR, "Could not sigaction(SIGTERM). %s (%d)", 193 strerror(errno), errno); 194 exit(1); 195 } 196 197 if (sigaction(SIGHUP, &sa, NULL) < 0) { 198 syslog(LOG_ERR, "Could not sigaction(SIGHUP). %s (%d)", 199 strerror(errno), errno); 200 exit(1); 201 } 202 203 if (sigaction(SIGINT, &sa, NULL) < 0) { 204 syslog(LOG_ERR, "Could not sigaction(SIGINT). %s (%d)", 205 strerror(errno), errno); 206 exit(1); 207 } 208 209 sa.sa_handler = SIG_IGN; 210 sa.sa_flags = SA_NOCLDWAIT; 211 212 if (sigaction(SIGCHLD, &sa, NULL) < 0) { 213 syslog(LOG_ERR, "Could not sigaction(SIGCHLD). %s (%d)", 214 strerror(errno), errno); 215 exit(1); 216 } 217 218 /* bind socket and listen for incoming connections */ 219 sock_addr.rfcomm_len = sizeof(sock_addr); 220 sock_addr.rfcomm_family = AF_BLUETOOTH; 221 memcpy(&sock_addr.rfcomm_bdaddr, &addr, 222 sizeof(sock_addr.rfcomm_bdaddr)); 223 sock_addr.rfcomm_channel = channel; 224 225 if (bind(s, (struct sockaddr *) &sock_addr, 226 sizeof(sock_addr)) < 0) { 227 syslog(LOG_ERR, "Could not bind socket. %s (%d)", 228 strerror(errno), errno); 229 exit(1); 230 } 231 232 if (listen(s, 10) < 0) { 233 syslog(LOG_ERR, "Could not listen on socket. %s (%d)", 234 strerror(errno), errno); 235 exit(1); 236 } 237 238 ss = sdp_open_local(NULL); 239 if (ss == NULL) { 240 syslog(LOG_ERR, "Unable to create local SDP session"); 241 exit(1); 242 } 243 244 if (sdp_error(ss) != 0) { 245 syslog(LOG_ERR, "Unable to open local SDP session. " \ 246 "%s (%d)", strerror(sdp_error(ss)), 247 sdp_error(ss)); 248 exit(1); 249 } 250 251 memset(&lan, 0, sizeof(lan)); 252 lan.server_channel = channel; 253 254 if (sdp_register_service(ss, 255 SDP_SERVICE_CLASS_LAN_ACCESS_USING_PPP, 256 &addr, (void *) &lan, sizeof(lan), NULL) != 0) { 257 syslog(LOG_ERR, "Unable to register LAN service with " \ 258 "local SDP daemon. %s (%d)", 259 strerror(sdp_error(ss)), sdp_error(ss)); 260 exit(1); 261 } 262 263 /* 264 * Register DUN (Dial-Up Networking) service on the same 265 * RFCOMM channel if requested. There is really no good reason 266 * to not to support this. AT-command exchange can be faked 267 * with chat script in ppp.conf 268 */ 269 270 if (regdun) { 271 sdp_dun_profile_t dun; 272 273 memset(&dun, 0, sizeof(dun)); 274 dun.server_channel = channel; 275 276 if (sdp_register_service(ss, 277 SDP_SERVICE_CLASS_DIALUP_NETWORKING, 278 &addr, (void *) &dun, sizeof(dun), 279 NULL) != 0) { 280 syslog(LOG_ERR, "Unable to register DUN " \ 281 "service with local SDP daemon. " \ 282 "%s (%d)", strerror(sdp_error(ss)), 283 sdp_error(ss)); 284 exit(1); 285 } 286 } 287 288 /* 289 * Register SP (Serial Port) service on the same RFCOMM channel 290 * if requested. It appears that some cell phones are using so 291 * called "callback mechanism". In this scenario user is trying 292 * to connect his cell phone to the Internet, and, user's host 293 * computer is acting as the gateway server. It seems that it 294 * is not possible to tell the phone to just connect and start 295 * using the LAN service. Instead the user's host computer must 296 * "jump start" the phone by connecting to the phone's SP 297 * service. What happens next is the phone kills the existing 298 * connection and opens another connection back to the user's 299 * host computer. The phone really wants to use LAN service, 300 * but for whatever reason it looks for SP service on the 301 * user's host computer. This brain damaged behavior was 302 * reported for Nokia 6600 and Sony/Ericsson P900. Both phones 303 * are Symbian-based phones. Perhaps this is a Symbian problem? 304 */ 305 306 if (regsp) { 307 sdp_sp_profile_t sp; 308 309 memset(&sp, 0, sizeof(sp)); 310 sp.server_channel = channel; 311 312 if (sdp_register_service(ss, 313 SDP_SERVICE_CLASS_SERIAL_PORT, 314 &addr, (void *) &sp, sizeof(sp), 315 NULL) != 0) { 316 syslog(LOG_ERR, "Unable to register SP " \ 317 "service with local SDP daemon. " \ 318 "%s (%d)", strerror(sdp_error(ss)), 319 sdp_error(ss)); 320 exit(1); 321 } 322 } 323 324 for (done = 0; !done; ) { 325 socklen_t len = sizeof(sock_addr); 326 int s1 = accept(s, (struct sockaddr *) &sock_addr, &len); 327 328 if (s1 < 0) { 329 syslog(LOG_ERR, "Could not accept connection " \ 330 "on socket. %s (%d)", strerror(errno), 331 errno); 332 exit(1); 333 } 334 335 pid = fork(); 336 if (pid == (pid_t) -1) { 337 syslog(LOG_ERR, "Could not fork(). %s (%d)", 338 strerror(errno), errno); 339 exit(1); 340 } 341 342 if (pid == 0) { 343 sdp_close(ss); 344 close(s); 345 346 /* Reset signal handler */ 347 memset(&sa, 0, sizeof(sa)); 348 sa.sa_handler = SIG_DFL; 349 350 sigaction(SIGTERM, &sa, NULL); 351 sigaction(SIGHUP, &sa, NULL); 352 sigaction(SIGINT, &sa, NULL); 353 sigaction(SIGCHLD, &sa, NULL); 354 355 /* Become daemon */ 356 daemon(0, 0); 357 358 /* 359 * XXX Make sure user does not shoot himself 360 * in the foot. Do not pass unit option to the 361 * PPP when operating in the server mode. 362 */ 363 364 exec_ppp(s1, NULL, label); 365 } else 366 close(s1); 367 } 368 } else { 369 sock_addr.rfcomm_len = sizeof(sock_addr); 370 sock_addr.rfcomm_family = AF_BLUETOOTH; 371 memcpy(&sock_addr.rfcomm_bdaddr, NG_HCI_BDADDR_ANY, 372 sizeof(sock_addr.rfcomm_bdaddr)); 373 sock_addr.rfcomm_channel = 0; 374 375 if (bind(s, (struct sockaddr *) &sock_addr, 376 sizeof(sock_addr)) < 0) { 377 syslog(LOG_ERR, "Could not bind socket. %s (%d)", 378 strerror(errno), errno); 379 exit(1); 380 } 381 382 memcpy(&sock_addr.rfcomm_bdaddr, &addr, 383 sizeof(sock_addr.rfcomm_bdaddr)); 384 sock_addr.rfcomm_channel = channel; 385 386 if (connect(s, (struct sockaddr *) &sock_addr, 387 sizeof(sock_addr)) < 0) { 388 syslog(LOG_ERR, "Could not connect socket. %s (%d)", 389 strerror(errno), errno); 390 exit(1); 391 } 392 393 exec_ppp(s, unit, label); 394 } 395 396 exit(0); 397 } /* main */ 398 399 /* 400 * Redirects stdin/stdout to s, stderr to /dev/null and exec 401 * 'ppp -direct -quiet [-unit N] label'. Never returns. 402 */ 403 404 static void 405 exec_ppp(int s, char *unit, char *label) 406 { 407 char ppp[] = "/usr/sbin/ppp"; 408 char *ppp_args[] = { ppp, "-direct", "-quiet", 409 NULL, NULL, NULL, NULL }; 410 411 close(0); 412 if (dup(s) < 0) { 413 syslog(LOG_ERR, "Could not dup(0). %s (%d)", 414 strerror(errno), errno); 415 exit(1); 416 } 417 418 close(1); 419 if (dup(s) < 0) { 420 syslog(LOG_ERR, "Could not dup(1). %s (%d)", 421 strerror(errno), errno); 422 exit(1); 423 } 424 425 close(2); 426 open("/dev/null", O_RDWR); 427 428 if (unit != NULL) { 429 ppp_args[3] = "-unit"; 430 ppp_args[4] = unit; 431 ppp_args[5] = label; 432 } else 433 ppp_args[3] = label; 434 435 if (execv(ppp, ppp_args) < 0) { 436 syslog(LOG_ERR, "Could not exec(%s -direct -quiet%s%s %s). " \ 437 "%s (%d)", ppp, (unit != NULL)? " -unit " : "", 438 (unit != NULL)? unit : "", label, 439 strerror(errno), errno); 440 exit(1); 441 } 442 } /* run_ppp */ 443 444 /* Signal handler */ 445 static void 446 sighandler(int s) 447 { 448 done = 1; 449 } /* sighandler */ 450 451 /* Display usage and exit */ 452 static void 453 usage(void) 454 { 455 fprintf(stdout, 456 "Usage: %s options\n" \ 457 "Where options are:\n" \ 458 "\t-a address Address to listen on or connect to (required for client)\n" \ 459 "\t-c Act as a clinet (default)\n" \ 460 "\t-C channel RFCOMM channel to listen on or connect to (required)\n" \ 461 "\t-d Run in foreground\n" \ 462 "\t-D Register Dial-Up Networking service (server mode only)\n" \ 463 "\t-l label Use PPP label (required)\n" \ 464 "\t-s Act as a server\n" \ 465 "\t-S Register Serial Port service (server mode only)\n" \ 466 "\t-u N Tell PPP to operate on /dev/tunN (client mode only)\n" \ 467 "\t-h Display this message\n", RFCOMM_PPPD); 468 469 exit(255); 470 } /* usage */ 471 472