tun.c

   1 /*
   2  * OpenConnect (SSL + DTLS) VPN client
   3  *
   4  * Copyright © 2008-2010 Intel Corporation.
   5  *
   6  * Author: David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public License
  10  * version 2.1, as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to:
  19  *
  20  *   Free Software Foundation, Inc.
  21  *   51 Franklin Street, Fifth Floor,
  22  *   Boston, MA 02110-1301 USA
  23  */
  24
  25 #include <sys/types.h>
  26 #include <sys/stat.h>
  27 #include <sys/socket.h>
  28 #include <sys/ioctl.h>
  29 #include <string.h>
  30 #include <signal.h>
  31 #include <fcntl.h>
  32 #include <unistd.h>
  33 #include <netdb.h>
  34 #include <netinet/in_systm.h>
  35 #include <netinet/in.h>
  36 #include <netinet/ip.h>
  37 #include <net/if.h>
  38 #include <arpa/inet.h>
  39 #include <errno.h>
  40 #include <ctype.h>
  41 #if defined(__sun__)
  42 #include <stropts.h>
  43 #include <sys/sockio.h>
  44 #include <net/if_tun.h>
  45 #ifndef TUNNEWPPA
  46 #error "Install TAP driver from http://www.whiteboard.ne.jp/~admin2/tuntap/"
  47 #endif
  48 #endif
  49
  50 #include "openconnect-internal.h"
  51
  52 /*
  53  * If an if_tun.h include file was found anywhere (by the Makefile), it's
  54  * included. Else, we end up assuming that we have BSD-style devices such
  55  * as /dev/tun0 etc.
  56  */
  57 #ifdef IF_TUN_HDR
  58 #include IF_TUN_HDR
  59 #endif
  60
  61 /*
  62  * The OS X tun/tap driver doesn't provide a header file; you're expected
  63  * to define this for yourself.
  64  */
  65 #ifdef __APPLE__
  66 #define TUNSIFHEAD  _IOW('t', 96, int)
  67 #endif
  68
  69 /*
  70  * OpenBSD always puts the protocol family prefix onto packets. Other
  71  * systems let us enable that with the TUNSIFHEAD ioctl, and some of them
  72  * (e.g. FreeBSD) _need_ it otherwise they'll interpret IPv6 packets as IPv4.
  73  */
  74 #if defined(__OpenBSD__) || defined(TUNSIFHEAD)
  75 #define TUN_HAS_AF_PREFIX 1
  76 #define AF_PREFIX_SIZE (sizeof(int))
  77 #else
  78 #define AF_PREFIX_SIZE (0)
  79 #endif
  80
  81 #ifdef __sun__
  82 static int local_config_tun(struct openconnect_info *vpninfo, int mtu_only)
  83 {
  84         if (!mtu_only)
  85                 vpn_progress(vpninfo, PRG_ERR,
  86                              _("No vpnc-script configured. Need Solaris IP-setting code\n"));
  87         return 0;
  88 }
  89 #else
  90 static int local_config_tun(struct openconnect_info *vpninfo, int mtu_only)
  91 {
  92         struct ifreq ifr;
  93         int net_fd;
  94
  95         net_fd = socket(PF_INET, SOCK_DGRAM, 0);
  96         if (net_fd < 0) {
  97                 perror(_("open net"));
  98                 return -EINVAL;
  99         }
 100         memset(&ifr, 0, sizeof(ifr));
 101         strncpy(ifr.ifr_name, vpninfo->ifname, sizeof(ifr.ifr_name) - 1);
 102
 103         if (!mtu_only) {
 104                 struct sockaddr_in addr;
 105
 106                 if (ioctl(net_fd, SIOCGIFFLAGS, &ifr) < 0)
 107                         perror(_("SIOCGIFFLAGS"));
 108
 109                 ifr.ifr_flags |= IFF_UP | IFF_POINTOPOINT;
 110                 if (ioctl(net_fd, SIOCSIFFLAGS, &ifr) < 0)
 111                         perror(_("SIOCSIFFLAGS"));
 112
 113                 addr.sin_family = AF_INET;
 114                 addr.sin_addr.s_addr = inet_addr(vpninfo->vpn_addr);
 115                 memcpy(&ifr.ifr_addr, &addr, sizeof(addr));
 116                 if (ioctl(net_fd, SIOCSIFADDR, &ifr) < 0)
 117                         perror(_("SIOCSIFADDR"));
 118         }
 119
 120         ifr.ifr_mtu = vpninfo->mtu;
 121         if (ioctl(net_fd, SIOCSIFMTU, &ifr) < 0)
 122                 perror(_("SIOCSIFMTU"));
 123
 124         close(net_fd);
 125
 126         return 0;
 127 }
 128 #endif
 129
 130 static int setenv_int(const char *opt, int value)
 131 {
 132         char buf[16];
 133         sprintf(buf, "%d", value);
 134         return setenv(opt, buf, 1);
 135 }
 136
 137 static int netmasklen(struct in_addr addr)
 138 {
 139         int masklen;
 140
 141         for (masklen = 0; masklen < 32; masklen++) {
 142                 if (ntohl(addr.s_addr) >= (0xffffffff << masklen))
 143                         break;
 144         }
 145         return 32 - masklen;
 146 }
 147
 148 static int process_split_xxclude(struct openconnect_info *vpninfo,
 149                                  int include, const char *route, int *v4_incs,
 150                                  int *v6_incs)
 151 {
 152         struct in_addr addr;
 153         const char *in_ex = include?"IN":"EX";
 154         char envname[80];
 155         char *slash;
 156
 157         slash = strchr(route, '/');
 158         if (!slash) {
 159         badinc:
 160                 if (include)
 161                         vpn_progress(vpninfo, PRG_ERR,
 162                                      _("Discard bad split include: \"%s\"\n"),
 163                                      route);
 164                 else
 165                         vpn_progress(vpninfo, PRG_ERR,
 166                                      _("Discard bad split exclude: \"%s\"\n"),
 167                                      route);
 168                 return -EINVAL;
 169         }
 170
 171         *slash = 0;
 172
 173         if (strchr(route, ':')) {
 174                 snprintf(envname, 79, "CISCO_IPV6_SPLIT_%sC_%d_ADDR", in_ex,
 175                          *v6_incs);
 176                 setenv(envname, route, 1);
 177
 178                 snprintf(envname, 79, "CISCO_IPV6_SPLIT_%sC_%d_MASKLEN", in_ex,
 179                          *v6_incs);
 180                 setenv(envname, slash+1, 1);
 181
 182                 (*v6_incs)++;
 183                 return 0;
 184         }
 185
 186         if (!inet_aton(route, &addr)) {
 187                 *slash = '/';
 188                 goto badinc;
 189         }
 190
 191         envname[79] = 0;
 192         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_ADDR", in_ex, *v4_incs);
 193         setenv(envname, route, 1);
 194
 195         /* Put it back how we found it */
 196         *slash = '/';
 197
 198         if (!inet_aton(slash+1, &addr))
 199                 goto badinc;
 200
 201         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASK", in_ex, *v4_incs);
 202         setenv(envname, slash+1, 1);
 203
 204         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASKLEN", in_ex, *v4_incs);
 205         setenv_int(envname, netmasklen(addr));
 206
 207         (*v4_incs)++;
 208         return 0;
 209 }
 210
 211 static int appendenv(const char *opt, const char *new)
 212 {
 213         char buf[1024];
 214         char *old = getenv(opt);
 215
 216         buf[1023] = 0;
 217         if (old)
 218                 snprintf(buf, 1023, "%s %s", old, new);
 219         else
 220                 snprintf(buf, 1023, "%s", new);
 221
 222         return setenv(opt, buf, 1);
 223 }
 224
 225 static void setenv_cstp_opts(struct openconnect_info *vpninfo)
 226 {
 227         char *env_buf;
 228         int buflen = 0;
 229         int bufofs = 0;
 230         struct vpn_option *opt;
 231
 232         for (opt = vpninfo->cstp_options; opt; opt = opt->next)
 233                 buflen += 2 + strlen(opt->option) + strlen(opt->value);
 234
 235         env_buf = malloc(buflen + 1);
 236         if (!env_buf)
 237                 return;
 238
 239         env_buf[buflen] = 0;
 240
 241         for (opt = vpninfo->cstp_options; opt; opt = opt->next)
 242                 bufofs += snprintf(env_buf + bufofs, buflen - bufofs,
 243                                    "%s=%s\n", opt->option, opt->value);
 244
 245         setenv("CISCO_CSTP_OPTIONS", env_buf, 1);
 246         free(env_buf);
 247 }
 248
 249 static void set_banner(struct openconnect_info *vpninfo)
 250 {
 251         char *banner, *q;
 252         const char *p;
 253
 254         if (!vpninfo->banner || !(banner = malloc(strlen(vpninfo->banner)))) {
 255                 unsetenv("CISCO_BANNER");
 256                 return;
 257         }
 258         p = vpninfo->banner;
 259         q = banner;
 260
 261         while (*p) {
 262                 if (*p == '%' && isxdigit((int)(unsigned char)p[1]) &&
 263                     isxdigit((int)(unsigned char)p[2])) {
 264                         *(q++) = unhex(p + 1);
 265                         p += 3;
 266                 } else
 267                         *(q++) = *(p++);
 268         }
 269         *q = 0;
 270         setenv("CISCO_BANNER", banner, 1);
 271
 272         free(banner);
 273 }
 274
 275 static void set_script_env(struct openconnect_info *vpninfo)
 276 {
 277         char host[80];
 278         int ret = getnameinfo(vpninfo->peer_addr, vpninfo->peer_addrlen, host,
 279                               sizeof(host), NULL, 0, NI_NUMERICHOST);
 280         if (!ret)
 281                 setenv("VPNGATEWAY", host, 1);
 282
 283         setenv("reason", "connect", 1);
 284         set_banner(vpninfo);
 285         unsetenv("CISCO_SPLIT_INC");
 286         unsetenv("CISCO_SPLIT_EXC");
 287
 288         setenv_int("INTERNAL_IP4_MTU", vpninfo->mtu);
 289
 290         if (vpninfo->vpn_addr) {
 291                 setenv("INTERNAL_IP4_ADDRESS", vpninfo->vpn_addr, 1);
 292                 if (vpninfo->vpn_netmask) {
 293                         struct in_addr addr;
 294                         struct in_addr mask;
 295
 296                         if (inet_aton(vpninfo->vpn_addr, &addr) &&
 297                             inet_aton(vpninfo->vpn_netmask, &mask)) {
 298                                 char *netaddr;
 299
 300                                 addr.s_addr &= mask.s_addr;
 301                                 netaddr = inet_ntoa(addr);
 302
 303                                 setenv("INTERNAL_IP4_NETADDR", netaddr, 1);
 304                                 setenv("INTERNAL_IP4_NETMASK", vpninfo->vpn_netmask, 1);
 305                                 setenv_int("INTERNAL_IP4_NETMASKLEN", netmasklen(mask));
 306                         }
 307                 }
 308         }
 309         if (vpninfo->vpn_addr6) {
 310                 setenv("INTERNAL_IP6_ADDRESS", vpninfo->vpn_addr6, 1);
 311                 setenv("INTERNAL_IP6_NETMASK", vpninfo->vpn_netmask6, 1);
 312         }
 313
 314         if (vpninfo->vpn_dns[0])
 315                 setenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[0], 1);
 316         else
 317                 unsetenv("INTERNAL_IP4_DNS");
 318         if (vpninfo->vpn_dns[1])
 319                 appendenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[1]);
 320         if (vpninfo->vpn_dns[2])
 321                 appendenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[2]);
 322
 323         if (vpninfo->vpn_nbns[0])
 324                 setenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[0], 1);
 325         else
 326                 unsetenv("INTERNAL_IP4_NBNS");
 327         if (vpninfo->vpn_nbns[1])
 328                 appendenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[1]);
 329         if (vpninfo->vpn_nbns[2])
 330                 appendenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[2]);
 331
 332         if (vpninfo->vpn_domain)
 333                 setenv("CISCO_DEF_DOMAIN", vpninfo->vpn_domain, 1);
 334         else unsetenv ("CISCO_DEF_DOMAIN");
 335
 336         if (vpninfo->vpn_proxy_pac)
 337                 setenv("CISCO_PROXY_PAC", vpninfo->vpn_proxy_pac, 1);
 338
 339         if (vpninfo->split_includes) {
 340                 struct split_include *this = vpninfo->split_includes;
 341                 int nr_split_includes = 0;
 342                 int nr_v6_split_includes = 0;
 343
 344                 while (this) {
 345                         process_split_xxclude(vpninfo, 1, this->route,
 346                                               &nr_split_includes,
 347                                               &nr_v6_split_includes);
 348                         this = this->next;
 349                 }
 350                 if (nr_split_includes)
 351                         setenv_int("CISCO_SPLIT_INC", nr_split_includes);
 352                 if (nr_v6_split_includes)
 353                         setenv_int("CISCO_IPV6_SPLIT_INC", nr_v6_split_includes);
 354         }
 355         if (vpninfo->split_excludes) {
 356                 struct split_include *this = vpninfo->split_excludes;
 357                 int nr_split_excludes = 0;
 358                 int nr_v6_split_excludes = 0;
 359
 360                 while (this) {
 361                         process_split_xxclude(vpninfo, 0, this->route,
 362                                               &nr_split_excludes,
 363                                               &nr_v6_split_excludes);
 364                         this = this->next;
 365                 }
 366                 if (nr_split_excludes)
 367                         setenv_int("CISCO_SPLIT_EXC", nr_split_excludes);
 368                 if (nr_v6_split_excludes)
 369                         setenv_int("CISCO_IPV6_SPLIT_EXC", nr_v6_split_excludes);
 370         }
 371         setenv_cstp_opts(vpninfo);
 372 }
 373
 374 static int script_config_tun(struct openconnect_info *vpninfo)
 375 {
 376         if (system(vpninfo->vpnc_script)) {
 377                 int e = errno;
 378                 vpn_progress(vpninfo, PRG_ERR,
 379                              _("Failed to spawn script '%s': %s\n"),
 380                              vpninfo->vpnc_script, strerror(e));
 381                 return -e;
 382         }
 383         return 0;
 384 }
 385
 386 void script_reconnect (struct openconnect_info *vpninfo)
 387 {
 388         setenv("reason", "reconnect", 1);
 389         script_config_tun(vpninfo);
 390 }
 391
 392 /* Set up a tuntap device. */
 393 int setup_tun(struct openconnect_info *vpninfo)
 394 {
 395         int tun_fd;
 396
 397         set_script_env(vpninfo);
 398
 399         if (vpninfo->script_tun) {
 400                 pid_t child;
 401                 int fds[2];
 402
 403                 if (socketpair(AF_UNIX, SOCK_DGRAM, 0, fds)) {
 404                         perror(_("socketpair"));
 405                         exit(1);
 406                 }
 407                 tun_fd = fds[0];
 408                 child = fork();
 409                 if (child < 0) {
 410                         perror(_("fork"));
 411                         exit(1);
 412                 } else if (!child) {
 413                         close(tun_fd);
 414                         setenv_int("VPNFD", fds[1]);
 415                         execl("/bin/sh", "/bin/sh", "-c", vpninfo->vpnc_script, NULL);
 416                         perror(_("execl"));
 417                         exit(1);
 418                 }
 419                 close(fds[1]);
 420                 vpninfo->script_tun = child;
 421                 vpninfo->ifname = strdup(_("(script)"));
 422         } else {
 423 #ifdef IFF_TUN /* Linux */
 424                 struct ifreq ifr;
 425                 int tunerr;
 426
 427                 tun_fd = open("/dev/net/tun", O_RDWR);
 428                 if (tun_fd < 0) {
 429                         /* Android has /dev/tun instead of /dev/net/tun
 430                            Since other systems might have too, just try it
 431                            as a fallback instead of using ifdef __ANDROID__ */
 432                         tunerr = errno;
 433                         tun_fd = open("/dev/tun", O_RDWR);
 434                 }
 435                 if (tun_fd < 0) {
 436                         /* If the error on /dev/tun is ENOENT, that's boring.
 437                            Use the error we got on /dev/net/tun instead */
 438                         if (errno != -ENOENT)
 439                                 tunerr = errno;
 440
 441                         vpn_progress(vpninfo, PRG_ERR,
 442                                      _("Failed to open tun device: %s\n"),
 443                                      strerror(tunerr));
 444                         exit(1);
 445                 }
 446                 memset(&ifr, 0, sizeof(ifr));
 447                 ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
 448                 if (vpninfo->ifname)
 449                         strncpy(ifr.ifr_name, vpninfo->ifname,
 450                                 sizeof(ifr.ifr_name) - 1);
 451                 if (ioctl(tun_fd, TUNSETIFF, (void *) &ifr) < 0) {
 452                         vpn_progress(vpninfo, PRG_ERR,
 453                                      _("TUNSETIFF failed: %s\n"),
 454                                      strerror(errno));
 455                         exit(1);
 456                 }
 457                 if (!vpninfo->ifname)
 458                         vpninfo->ifname = strdup(ifr.ifr_name);
 459 #elif defined (__sun__)
 460                 static char tun_name[80];
 461                 int tun2_fd, ip_fd = open("/dev/ip", O_RDWR);
 462                 int unit_nr, mux_id;
 463                 struct ifreq ifr;
 464
 465                 if (ip_fd < 0) {
 466                         perror(_("open /dev/ip"));
 467                         return -EIO;
 468                 }
 469
 470                 tun_fd = open("/dev/tun", O_RDWR);
 471                 if (tun_fd < 0) {
 472                         perror(_("open /dev/tun"));
 473                         close(ip_fd);
 474                         return -EIO;
 475                 }
 476
 477                 unit_nr = ioctl(tun_fd, TUNNEWPPA, -1);
 478                 if (unit_nr < 0) {
 479                         perror(_("Failed to create new tun"));
 480                         close(tun_fd);
 481                         close(ip_fd);
 482                         return -EIO;
 483                 }
 484
 485                 tun2_fd = open("/dev/tun", O_RDWR);
 486                 if (tun2_fd < 0) {
 487                         perror(_("open /dev/tun again"));
 488                         close(tun_fd);
 489                         close(ip_fd);
 490                         return -EIO;
 491                 }
 492                 if (ioctl(tun2_fd, I_PUSH, "ip") < 0) {
 493                         perror(_("Can't push IP"));
 494                         close(tun2_fd);
 495                         close(tun_fd);
 496                         close(ip_fd);
 497                         return -EIO;
 498                 }
 499                 if (ioctl(tun2_fd, IF_UNITSEL, &unit_nr) < 0) {
 500                         perror(_("Can't select unit"));
 501                         close(tun2_fd);
 502                         close(tun_fd);
 503                         close(ip_fd);
 504                         return -EIO;
 505                 }
 506                 mux_id = ioctl(ip_fd, I_LINK, tun2_fd);
 507                 if (mux_id < 0) {
 508                         perror(_("Can't link tun to IP"));
 509                         close(tun2_fd);
 510                         close(tun_fd);
 511                         close(ip_fd);
 512                         return -EIO;
 513                 }
 514                 close(tun2_fd);
 515
 516                 sprintf(tun_name, "tun%d", unit_nr);
 517                 vpninfo->ifname = strdup(tun_name);
 518
 519                 memset(&ifr, 0, sizeof(ifr));
 520                 strcpy(ifr.ifr_name, tun_name);
 521                 ifr.ifr_ip_muxid = mux_id;
 522
 523                 if (ioctl(ip_fd, SIOCSIFMUXID, &ifr) < 0) {
 524                         perror(_("Set mux id"));
 525                         close(tun_fd);
 526                         close(ip_fd);
 527                         return -EIO;
 528                 }
 529                 vpninfo->ip_fd = ip_fd;
 530
 531 #else /* BSD et al have /dev/tun$x devices */
 532                 static char tun_name[80];
 533                 int i;
 534                 for (i = 0; i < 255; i++) {
 535                         sprintf(tun_name, "/dev/tun%d", i);
 536                         tun_fd = open(tun_name, O_RDWR);
 537                         if (tun_fd >= 0)
 538                                 break;
 539                 }
 540                 if (tun_fd < 0) {
 541                         perror(_("open tun"));
 542                         exit(1);
 543                 }
 544                 vpninfo->ifname = strdup(tun_name + 5);
 545 #ifdef TUNSIFHEAD
 546                 i = 1;
 547                 if (ioctl(tun_fd, TUNSIFHEAD, &i) < 0) {
 548                         perror(_("TUNSIFHEAD"));
 549                         exit(1);
 550                 }
 551 #endif
 552 #endif
 553                 if (vpninfo->vpnc_script) {
 554                         setenv("TUNDEV", vpninfo->ifname, 1);
 555                         script_config_tun(vpninfo);
 556                         /* We have to set the MTU for ourselves, because the script doesn't */
 557                         local_config_tun(vpninfo, 1);
 558                 } else
 559                         local_config_tun(vpninfo, 0);
 560         }
 561
 562         fcntl(tun_fd, F_SETFD, FD_CLOEXEC);
 563
 564         vpninfo->tun_fd = tun_fd;
 565
 566         if (vpninfo->select_nfds <= tun_fd)
 567                 vpninfo->select_nfds = tun_fd + 1;
 568
 569         FD_SET(tun_fd, &vpninfo->select_rfds);
 570
 571         fcntl(vpninfo->tun_fd, F_SETFL, fcntl(vpninfo->tun_fd, F_GETFL) | O_NONBLOCK);
 572
 573         return 0;
 574 }
 575
 576 static struct pkt *out_pkt;
 577
 578 int tun_mainloop(struct openconnect_info *vpninfo, int *timeout)
 579 {
 580         int work_done = 0;
 581         int moredata = 1;
 582
 583         if (FD_ISSET(vpninfo->tun_fd, &vpninfo->select_rfds)) {
 584                 while (moredata) {
 585                         int len = vpninfo->mtu;
 586
 587                         if (!out_pkt) {
 588                                 out_pkt = malloc(sizeof(struct pkt) + len);
 589                                 if (!out_pkt) {
 590                                         vpn_progress(vpninfo, PRG_ERR, "Allocation failed\n");
 591                                         break;
 592                                 }
 593                         }
 594
 595 #ifdef __sun__
 596                         /* On Solaris, if we're actually using tuntap and *not* just
 597                            passing packets through a UNIX socket to a child process,
 598                            we have to use getmsg() to ensure that we only get *one*
 599                            packet at a time. */
 600                         if (!vpninfo->script_tun) {
 601                                 struct strbuf strb;
 602                                 int flags = 0;
 603                                 int ret;
 604
 605                                 strb.buf = out_pkt->data;
 606                                 strb.maxlen = len;
 607                                 strb.len = 0;
 608                                 ret = getmsg(vpninfo->tun_fd, NULL, &strb, &flags);
 609                                 if (ret < 0)
 610                                         break;
 611
 612                                 if (!(ret & MOREDATA))
 613                                         moredata = 0;
 614                                 out_pkt->len = strb.len;
 615                         } else
 616 #endif /* __sun__ ... */
 617                         {
 618                                 len = read(vpninfo->tun_fd, out_pkt->data - AF_PREFIX_SIZE, len + AF_PREFIX_SIZE);
 619                                 if (len <= 0)
 620                                         break;
 621
 622                                 out_pkt->len = len - AF_PREFIX_SIZE;
 623                         }
 624
 625                         queue_packet(&vpninfo->outgoing_queue, out_pkt);
 626                         out_pkt = NULL;
 627
 628                         work_done = 1;
 629                         vpninfo->outgoing_qlen++;
 630                         if (vpninfo->outgoing_qlen == vpninfo->max_qlen) {
 631                                 FD_CLR(vpninfo->tun_fd, &vpninfo->select_rfds);
 632                                 break;
 633                         }
 634                 }
 635         } else if (vpninfo->outgoing_qlen < vpninfo->max_qlen) {
 636                 FD_SET(vpninfo->tun_fd, &vpninfo->select_rfds);
 637         }
 638
 639         /* The kernel returns -ENOMEM when the queue is full, so theoretically
 640            we could handle that and retry... but it doesn't let us poll() for
 641            the no-longer-full situation, so let's not bother. */
 642         while (vpninfo->incoming_queue) {
 643                 struct pkt *this = vpninfo->incoming_queue;
 644                 unsigned char *data = this->data;
 645                 int len = this->len;
 646
 647 #ifdef TUN_HAS_AF_PREFIX
 648                 if (!vpninfo->script_tun) {
 649                         struct ip *iph = (void *)data;
 650                         int type;
 651
 652                         if (iph->ip_v == 6)
 653                                 type = AF_INET6;
 654                         else if (iph->ip_v == 4)
 655                                 type = AF_INET;
 656                         else {
 657                                 static int complained = 0;
 658                                 if (!complained) {
 659                                         complained = 1;
 660                                         vpn_progress(vpninfo, PRG_ERR,
 661                                                      _("Unknown packet (len %d) received: %02x %02x %02x %02x...\n"),
 662                                                      len, data[0], data[1], data[2], data[3]);
 663                                 }
 664                                 free(this);
 665                                 continue;
 666                         }
 667                         data -= 4;
 668                         len += 4;
 669                         *(int *)data = htonl(type);
 670                 }
 671 #endif
 672                 vpninfo->incoming_queue = this->next;
 673
 674                 if (write(vpninfo->tun_fd, data, len) < 0) {
 675                         /* Handle death of "script" socket */
 676                         if (vpninfo->script_tun && errno == ENOTCONN) {
 677                                 vpninfo->quit_reason = "Client connection terminated";
 678                                 return 1;
 679                         }
 680                         vpn_progress(vpninfo, PRG_ERR,
 681                                      _("Failed to write incoming packet: %s\n"),
 682                                      strerror(errno));
 683                 }
 684                 free(this);
 685         }
 686         /* Work is not done if we just got rid of packets off the queue */
 687         return work_done;
 688 }
 689
 690 void shutdown_tun(struct openconnect_info *vpninfo)
 691 {
 692         if (vpninfo->script_tun) {
 693                 kill(vpninfo->script_tun, SIGHUP);
 694         } else {
 695                 if (vpninfo->vpnc_script) {
 696                         setenv("reason", "disconnect", 1);
 697                         if (system(vpninfo->vpnc_script) == -1) {
 698                                 vpn_progress(vpninfo, PRG_ERR,
 699                                              _("Failed to spawn script '%s': %s\n"),
 700                                              vpninfo->vpnc_script,
 701                                              strerror(errno));
 702                         }
 703                 }
 704 #ifdef __sun__
 705                 close(vpninfo->ip_fd);
 706                 vpninfo->ip_fd = -1;
 707 #endif
 708         }
 709
 710         close(vpninfo->tun_fd);
 711         vpninfo->tun_fd = -1;
 712 }