lib/lws-plat-unix.c

   1 #include "private-libwebsockets.h"
   2
   3 #include <pwd.h>
   4 #include <grp.h>
   5
   6 /*
   7  * included from libwebsockets.c for unix builds
   8  */
   9
  10 unsigned long long time_in_microseconds(void)
  11 {
  12         struct timeval tv;
  13         gettimeofday(&tv, NULL);
  14         return ((unsigned long long)tv.tv_sec * 1000000LL) + tv.tv_usec;
  15 }
  16
  17 LWS_VISIBLE int
  18 lws_get_random(struct lws_context *context, void *buf, int len)
  19 {
  20         return read(context->fd_random, (char *)buf, len);
  21 }
  22
  23 LWS_VISIBLE int
  24 lws_send_pipe_choked(struct lws *wsi)
  25 {
  26         struct lws_pollfd fds;
  27
  28         /* treat the fact we got a truncated send pending as if we're choked */
  29         if (wsi->trunc_len)
  30                 return 1;
  31
  32         fds.fd = wsi->sock;
  33         fds.events = POLLOUT;
  34         fds.revents = 0;
  35
  36         if (poll(&fds, 1, 0) != 1)
  37                 return 1;
  38
  39         if ((fds.revents & POLLOUT) == 0)
  40                 return 1;
  41
  42         /* okay to send another packet without blocking */
  43
  44         return 0;
  45 }
  46
  47 LWS_VISIBLE int
  48 lws_poll_listen_fd(struct lws_pollfd *fd)
  49 {
  50         return poll(fd, 1, 0);
  51 }
  52
  53 /*
  54  * This is just used to interrupt poll waiting
  55  * we don't have to do anything with it.
  56  */
  57 static void lws_sigusr2(int sig)
  58 {
  59 }
  60
  61 /**
  62  * lws_cancel_service() - Cancel servicing of pending websocket activity
  63  * @context:    Websocket context
  64  *
  65  *      This function let a call to lws_service() waiting for a timeout
  66  *      immediately return.
  67  */
  68 LWS_VISIBLE void
  69 lws_cancel_service(struct lws_context *context)
  70 {
  71         char buf = 0;
  72
  73         if (write(context->dummy_pipe_fds[1], &buf, sizeof(buf)) != 1)
  74                 lwsl_err("Cannot write to dummy pipe");
  75 }
  76
  77 LWS_VISIBLE void lwsl_emit_syslog(int level, const char *line)
  78 {
  79         int syslog_level = LOG_DEBUG;
  80
  81         switch (level) {
  82         case LLL_ERR:
  83                 syslog_level = LOG_ERR;
  84                 break;
  85         case LLL_WARN:
  86                 syslog_level = LOG_WARNING;
  87                 break;
  88         case LLL_NOTICE:
  89                 syslog_level = LOG_NOTICE;
  90                 break;
  91         case LLL_INFO:
  92                 syslog_level = LOG_INFO;
  93                 break;
  94         }
  95         syslog(syslog_level, "%s", line);
  96 }
  97
  98 LWS_VISIBLE int
  99 lws_plat_service(struct lws_context *context, int timeout_ms)
 100 {
 101         int n;
 102         int m;
 103         char buf;
 104         struct lws *wsi;
 105 #ifdef LWS_OPENSSL_SUPPORT
 106         struct lws *wsi_next;
 107 #endif
 108
 109         /* stay dead once we are dead */
 110
 111         if (!context)
 112                 return 1;
 113
 114         lws_libev_run(context);
 115
 116         if (!context->service_tid_detected) {
 117                 struct lws _lws;
 118
 119                 memset(&_lws, 0, sizeof(_lws));
 120                 _lws.context = context;
 121
 122                 context->service_tid_detected = context->protocols[0].callback(
 123                         &_lws, LWS_CALLBACK_GET_THREAD_ID, NULL, NULL, 0);
 124         }
 125         context->service_tid = context->service_tid_detected;
 126
 127         /* if we know we are draining rx ext, do not wait in poll */
 128         if (context->rx_draining_ext_list)
 129                 timeout_ms = 0;
 130
 131 #ifdef LWS_OPENSSL_SUPPORT
 132         /* if we know we have non-network pending data, do not wait in poll */
 133         if (lws_ssl_anybody_has_buffered_read(context)) {
 134                 timeout_ms = 0;
 135                 lwsl_err("ssl buffered read\n");
 136         }
 137 #endif
 138
 139         n = poll(context->fds, context->fds_count, timeout_ms);
 140
 141 #ifdef LWS_OPENSSL_SUPPORT
 142         if (!context->rx_draining_ext_list &&
 143             !lws_ssl_anybody_has_buffered_read(context) && n == 0) {
 144 #else
 145         if (!context->rx_draining_ext_list && n == 0) /* poll timeout */ {
 146 #endif
 147                 lws_service_fd(context, NULL);
 148                 return 0;
 149         }
 150
 151         if (n < 0) {
 152                 if (LWS_ERRNO != LWS_EINTR)
 153                         return -1;
 154                 return 0;
 155         }
 156
 157         /*
 158          * For all guys with already-available ext data to drain, if they are
 159          * not flowcontrolled, fake their POLLIN status
 160          */
 161         wsi = context->rx_draining_ext_list;
 162         while (wsi) {
 163                 context->fds[wsi->position_in_fds_table].revents |=
 164                         context->fds[wsi->position_in_fds_table].events & POLLIN;
 165                 wsi = wsi->u.ws.rx_draining_ext_list;
 166         }
 167
 168 #ifdef LWS_OPENSSL_SUPPORT
 169         /*
 170          * For all guys with buffered SSL read data already saved up, if they
 171          * are not flowcontrolled, fake their POLLIN status so they'll get
 172          * service to use up the buffered incoming data, even though their
 173          * network socket may have nothing
 174          */
 175
 176         wsi = context->pending_read_list;
 177         while (wsi) {
 178                 wsi_next = wsi->pending_read_list_next;
 179                 context->fds[wsi->position_in_fds_table].revents |=
 180                         context->fds[wsi->position_in_fds_table].events & POLLIN;
 181                 if (context->fds[wsi->position_in_fds_table].revents & POLLIN)
 182                         /*
 183                          * he's going to get serviced now, take him off the
 184                          * list of guys with buffered SSL.  If he still has some
 185                          * at the end of the service, he'll get put back on the
 186                          * list then.
 187                          */
 188                         lws_ssl_remove_wsi_from_buffered_list(wsi);
 189
 190                 wsi = wsi_next;
 191         }
 192 #endif
 193
 194         /* any socket with events to service? */
 195
 196         for (n = 0; n < context->fds_count; n++) {
 197                 if (!context->fds[n].revents)
 198                         continue;
 199
 200                 if (context->fds[n].fd == context->dummy_pipe_fds[0]) {
 201                         if (read(context->fds[n].fd, &buf, 1) != 1)
 202                                 lwsl_err("Cannot read from dummy pipe.");
 203                         continue;
 204                 }
 205
 206                 m = lws_service_fd(context, &context->fds[n]);
 207                 if (m < 0)
 208                         return -1;
 209                 /* if something closed, retry this slot */
 210                 if (m)
 211                         n--;
 212         }
 213
 214         return 0;
 215 }
 216
 217 LWS_VISIBLE int
 218 lws_plat_set_socket_options(struct lws_context *context, int fd)
 219 {
 220         int optval = 1;
 221         socklen_t optlen = sizeof(optval);
 222
 223 #if defined(__APPLE__) || \
 224     defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || \
 225     defined(__NetBSD__) || \
 226     defined(__OpenBSD__)
 227         struct protoent *tcp_proto;
 228 #endif
 229
 230         if (context->ka_time) {
 231                 /* enable keepalive on this socket */
 232                 optval = 1;
 233                 if (setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE,
 234                                (const void *)&optval, optlen) < 0)
 235                         return 1;
 236
 237 #if defined(__APPLE__) || \
 238     defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || \
 239     defined(__NetBSD__) || \
 240         defined(__CYGWIN__) || defined(__OpenBSD__)
 241
 242                 /*
 243                  * didn't find a way to set these per-socket, need to
 244                  * tune kernel systemwide values
 245                  */
 246 #else
 247                 /* set the keepalive conditions we want on it too */
 248                 optval = context->ka_time;
 249                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPIDLE,
 250                                (const void *)&optval, optlen) < 0)
 251                         return 1;
 252
 253                 optval = context->ka_interval;
 254                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPINTVL,
 255                                (const void *)&optval, optlen) < 0)
 256                         return 1;
 257
 258                 optval = context->ka_probes;
 259                 if (setsockopt(fd, IPPROTO_TCP, TCP_KEEPCNT,
 260                                (const void *)&optval, optlen) < 0)
 261                         return 1;
 262 #endif
 263         }
 264
 265         /* Disable Nagle */
 266         optval = 1;
 267 #if !defined(__APPLE__) && \
 268     !defined(__FreeBSD__) && !defined(__FreeBSD_kernel__) && \
 269     !defined(__NetBSD__) && \
 270     !defined(__OpenBSD__)
 271         if (setsockopt(fd, SOL_TCP, TCP_NODELAY, (const void *)&optval, optlen) < 0)
 272                 return 1;
 273 #else
 274         tcp_proto = getprotobyname("TCP");
 275         if (setsockopt(fd, tcp_proto->p_proto, TCP_NODELAY, &optval, optlen) < 0)
 276                 return 1;
 277 #endif
 278
 279         /* We are nonblocking... */
 280         if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
 281                 return 1;
 282
 283         return 0;
 284 }
 285
 286 LWS_VISIBLE void
 287 lws_plat_drop_app_privileges(struct lws_context_creation_info *info)
 288 {
 289         if (info->uid != -1) {
 290                 struct passwd *p = getpwuid(info->uid);
 291
 292                 if (p) {
 293                         initgroups(p->pw_name, info->gid);
 294                         if (setuid(info->uid))
 295                                 lwsl_warn("setuid: %s\n", strerror(LWS_ERRNO));
 296                         else
 297                                 lwsl_notice(" Set privs to user '%s'\n", p->pw_name);
 298                 } else
 299                         lwsl_warn("getpwuid: unable to find uid %d", info->uid);
 300         }
 301         if (info->gid != -1)
 302                 if (setgid(info->gid))
 303                         lwsl_warn("setgid: %s\n", strerror(LWS_ERRNO));
 304
 305 }
 306
 307 static void sigpipe_handler(int x)
 308 {
 309 }
 310
 311 LWS_VISIBLE int
 312 lws_plat_context_early_init(void)
 313 {
 314         sigset_t mask;
 315
 316         signal(SIGUSR2, lws_sigusr2);
 317         sigemptyset(&mask);
 318         sigaddset(&mask, SIGUSR2);
 319
 320         sigprocmask(SIG_BLOCK, &mask, NULL);
 321
 322         signal(SIGPIPE, sigpipe_handler);
 323
 324         return 0;
 325 }
 326
 327 LWS_VISIBLE void
 328 lws_plat_context_early_destroy(struct lws_context *context)
 329 {
 330 }
 331
 332 LWS_VISIBLE void
 333 lws_plat_context_late_destroy(struct lws_context *context)
 334 {
 335         if (context->lws_lookup)
 336                 lws_free(context->lws_lookup);
 337
 338         close(context->dummy_pipe_fds[0]);
 339         close(context->dummy_pipe_fds[1]);
 340         close(context->fd_random);
 341 }
 342
 343 /* cast a struct sockaddr_in6 * into addr for ipv6 */
 344
 345 LWS_VISIBLE int
 346 interface_to_sa(struct lws_context *context,
 347                 const char *ifname, struct sockaddr_in *addr, size_t addrlen)
 348 {
 349         int rc = -1;
 350
 351         struct ifaddrs *ifr;
 352         struct ifaddrs *ifc;
 353 #ifdef LWS_USE_IPV6
 354         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
 355 #endif
 356
 357         getifaddrs(&ifr);
 358         for (ifc = ifr; ifc != NULL && rc; ifc = ifc->ifa_next) {
 359                 if (!ifc->ifa_addr)
 360                         continue;
 361
 362                 lwsl_info(" interface %s vs %s\n", ifc->ifa_name, ifname);
 363
 364                 if (strcmp(ifc->ifa_name, ifname))
 365                         continue;
 366
 367                 switch (ifc->ifa_addr->sa_family) {
 368                 case AF_INET:
 369 #ifdef LWS_USE_IPV6
 370                         if (LWS_IPV6_ENABLED(context)) {
 371                                 /* map IPv4 to IPv6 */
 372                                 bzero((char *)&addr6->sin6_addr,
 373                                                 sizeof(struct in6_addr));
 374                                 addr6->sin6_addr.s6_addr[10] = 0xff;
 375                                 addr6->sin6_addr.s6_addr[11] = 0xff;
 376                                 memcpy(&addr6->sin6_addr.s6_addr[12],
 377                                         &((struct sockaddr_in *)ifc->ifa_addr)->sin_addr,
 378                                                         sizeof(struct in_addr));
 379                         } else
 380 #endif
 381                                 memcpy(addr,
 382                                         (struct sockaddr_in *)ifc->ifa_addr,
 383                                                     sizeof(struct sockaddr_in));
 384                         break;
 385 #ifdef LWS_USE_IPV6
 386                 case AF_INET6:
 387                         memcpy(&addr6->sin6_addr,
 388                           &((struct sockaddr_in6 *)ifc->ifa_addr)->sin6_addr,
 389                                                        sizeof(struct in6_addr));
 390                         break;
 391 #endif
 392                 default:
 393                         continue;
 394                 }
 395                 rc = 0;
 396         }
 397
 398         freeifaddrs(ifr);
 399
 400         if (rc == -1) {
 401                 /* check if bind to IP adddress */
 402 #ifdef LWS_USE_IPV6
 403                 if (inet_pton(AF_INET6, ifname, &addr6->sin6_addr) == 1)
 404                         rc = 0;
 405                 else
 406 #endif
 407                 if (inet_pton(AF_INET, ifname, &addr->sin_addr) == 1)
 408                         rc = 0;
 409         }
 410
 411         return rc;
 412 }
 413
 414 LWS_VISIBLE void
 415 lws_plat_insert_socket_into_fds(struct lws_context *context,
 416                                                        struct lws *wsi)
 417 {
 418         lws_libev_io(wsi, LWS_EV_START | LWS_EV_READ);
 419         context->fds[context->fds_count++].revents = 0;
 420 }
 421
 422 LWS_VISIBLE void
 423 lws_plat_delete_socket_from_fds(struct lws_context *context,
 424                                                 struct lws *wsi, int m)
 425 {
 426 }
 427
 428 LWS_VISIBLE void
 429 lws_plat_service_periodic(struct lws_context *context)
 430 {
 431         /* if our parent went down, don't linger around */
 432         if (context->started_with_parent &&
 433             kill(context->started_with_parent, 0) < 0)
 434                 kill(getpid(), SIGTERM);
 435 }
 436
 437 LWS_VISIBLE int
 438 lws_plat_change_pollfd(struct lws_context *context,
 439                       struct lws *wsi, struct lws_pollfd *pfd)
 440 {
 441         return 0;
 442 }
 443
 444 LWS_VISIBLE const char *
 445 lws_plat_inet_ntop(int af, const void *src, char *dst, int cnt)
 446 {
 447         return inet_ntop(af, src, dst, cnt);
 448 }
 449
 450 static lws_filefd_type
 451 _lws_plat_file_open(struct lws *wsi, const char *filename,
 452                     unsigned long *filelen, int flags)
 453 {
 454         struct stat stat_buf;
 455         int ret = open(filename, flags, 0664);
 456
 457         if (ret < 0)
 458                 return LWS_INVALID_FILE;
 459
 460         if (fstat(ret, &stat_buf) < 0) {
 461                 close(ret);
 462                 return LWS_INVALID_FILE;
 463         }
 464         *filelen = stat_buf.st_size;
 465         return ret;
 466 }
 467
 468 static int
 469 _lws_plat_file_close(struct lws *wsi, lws_filefd_type fd)
 470 {
 471         return close(fd);
 472 }
 473
 474 unsigned long
 475 _lws_plat_file_seek_cur(struct lws *wsi, lws_filefd_type fd, long offset)
 476 {
 477         return lseek(fd, offset, SEEK_CUR);
 478 }
 479
 480 static int
 481 _lws_plat_file_read(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
 482                     unsigned char *buf, unsigned long len)
 483 {
 484         long n;
 485
 486         n = read((int)fd, buf, len);
 487         if (n == -1) {
 488                 *amount = 0;
 489                 return -1;
 490         }
 491
 492         *amount = n;
 493
 494         return 0;
 495 }
 496
 497 static int
 498 _lws_plat_file_write(struct lws *wsi, lws_filefd_type fd, unsigned long *amount,
 499                      unsigned char *buf, unsigned long len)
 500 {
 501         long n;
 502
 503         n = write((int)fd, buf, len);
 504         if (n == -1) {
 505                 *amount = 0;
 506                 return -1;
 507         }
 508
 509         *amount = n;
 510
 511         return 0;
 512 }
 513
 514 LWS_VISIBLE int
 515 lws_plat_init(struct lws_context *context,
 516               struct lws_context_creation_info *info)
 517 {
 518         context->lws_lookup = lws_zalloc(sizeof(struct lws *) * context->max_fds);
 519         if (context->lws_lookup == NULL) {
 520                 lwsl_err(
 521                   "Unable to allocate lws_lookup array for %d connections\n",
 522                                                               context->max_fds);
 523                 return 1;
 524         }
 525
 526         lwsl_notice(" mem: platform fd map: %5u bytes\n",
 527                     sizeof(struct lws *) * context->max_fds);
 528
 529         context->fd_random = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY);
 530         if (context->fd_random < 0) {
 531                 lwsl_err("Unable to open random device %s %d\n",
 532                                     SYSTEM_RANDOM_FILEPATH, context->fd_random);
 533                 return 1;
 534         }
 535
 536         if (!lws_libev_init_fd_table(context)) {
 537                 /* otherwise libev handled it instead */
 538
 539                 if (pipe(context->dummy_pipe_fds)) {
 540                         lwsl_err("Unable to create pipe\n");
 541                         return 1;
 542                 }
 543         }
 544
 545         /* use the read end of pipe as first item */
 546         context->fds[0].fd = context->dummy_pipe_fds[0];
 547         context->fds[0].events = LWS_POLLIN;
 548         context->fds[0].revents = 0;
 549         context->fds_count = 1;
 550
 551         context->fops.open      = _lws_plat_file_open;
 552         context->fops.close     = _lws_plat_file_close;
 553         context->fops.seek_cur  = _lws_plat_file_seek_cur;
 554         context->fops.read      = _lws_plat_file_read;
 555         context->fops.write     = _lws_plat_file_write;
 556
 557         return 0;
 558 }