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 #endif
  77
  78 #ifdef __sun__
  79 static int local_config_tun(struct openconnect_info *vpninfo, int mtu_only)
  80 {
  81         if (!mtu_only)
  82                 vpn_progress(vpninfo, PRG_ERR,
  83                              _("No vpnc-script configured. Need Solaris IP-setting code\n"));
  84         return 0;
  85 }
  86 #else
  87 static int local_config_tun(struct openconnect_info *vpninfo, int mtu_only)
  88 {
  89         struct ifreq ifr;
  90         int net_fd;
  91
  92         net_fd = socket(PF_INET, SOCK_DGRAM, 0);
  93         if (net_fd < 0) {
  94                 perror(_("open net"));
  95                 return -EINVAL;
  96         }
  97         memset(&ifr, 0, sizeof(ifr));
  98         strncpy(ifr.ifr_name, vpninfo->ifname, sizeof(ifr.ifr_name) - 1);
  99
 100         if (!mtu_only) {
 101                 struct sockaddr_in addr;
 102
 103                 if (ioctl(net_fd, SIOCGIFFLAGS, &ifr) < 0)
 104                         perror(_("SIOCGIFFLAGS"));
 105
 106                 ifr.ifr_flags |= IFF_UP | IFF_POINTOPOINT;
 107                 if (ioctl(net_fd, SIOCSIFFLAGS, &ifr) < 0)
 108                         perror(_("SIOCSIFFLAGS"));
 109
 110                 addr.sin_family = AF_INET;
 111                 addr.sin_addr.s_addr = inet_addr(vpninfo->vpn_addr);
 112                 memcpy(&ifr.ifr_addr, &addr, sizeof(addr));
 113                 if (ioctl(net_fd, SIOCSIFADDR, &ifr) < 0)
 114                         perror(_("SIOCSIFADDR"));
 115         }
 116
 117         ifr.ifr_mtu = vpninfo->mtu;
 118         if (ioctl(net_fd, SIOCSIFMTU, &ifr) < 0)
 119                 perror(_("SIOCSIFMTU"));
 120
 121         close(net_fd);
 122
 123         return 0;
 124 }
 125 #endif
 126
 127 static int setenv_int(const char *opt, int value)
 128 {
 129         char buf[16];
 130         sprintf(buf, "%d", value);
 131         return setenv(opt, buf, 1);
 132 }
 133
 134 static int netmasklen(struct in_addr addr)
 135 {
 136         int masklen;
 137
 138         for (masklen = 0; masklen < 32; masklen++) {
 139                 if (ntohl(addr.s_addr) >= (0xffffffff << masklen))
 140                         break;
 141         }
 142         return 32 - masklen;
 143 }
 144
 145 static int process_split_xxclude(struct openconnect_info *vpninfo,
 146                                  int include, const char *route, int *v4_incs,
 147                                  int *v6_incs)
 148 {
 149         struct in_addr addr;
 150         const char *in_ex = include?"IN":"EX";
 151         char envname[80];
 152         char *slash;
 153
 154         slash = strchr(route, '/');
 155         if (!slash) {
 156         badinc:
 157                 if (include)
 158                         vpn_progress(vpninfo, PRG_ERR,
 159                                      _("Discard bad split include: \"%s\"\n"),
 160                                      route);
 161                 else
 162                         vpn_progress(vpninfo, PRG_ERR,
 163                                      _("Discard bad split exclude: \"%s\"\n"),
 164                                      route);
 165                 return -EINVAL;
 166         }
 167
 168         *slash = 0;
 169
 170         if (strchr(route, ':')) {
 171                 snprintf(envname, 79, "CISCO_IPV6_SPLIT_%sC_%d_ADDR", in_ex,
 172                          *v6_incs);
 173                 setenv(envname, route, 1);
 174
 175                 snprintf(envname, 79, "CISCO_IPV6_SPLIT_%sC_%d_MASKLEN", in_ex,
 176                          *v6_incs);
 177                 setenv(envname, slash+1, 1);
 178
 179                 (*v6_incs)++;
 180                 return 0;
 181         }
 182
 183         if (!inet_aton(route, &addr)) {
 184                 *slash = '/';
 185                 goto badinc;
 186         }
 187
 188         envname[79] = 0;
 189         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_ADDR", in_ex, *v4_incs);
 190         setenv(envname, route, 1);
 191
 192         /* Put it back how we found it */
 193         *slash = '/';
 194
 195         if (!inet_aton(slash+1, &addr))
 196                 goto badinc;
 197
 198         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASK", in_ex, *v4_incs);
 199         setenv(envname, slash+1, 1);
 200
 201         snprintf(envname, 79, "CISCO_SPLIT_%sC_%d_MASKLEN", in_ex, *v4_incs);
 202         setenv_int(envname, netmasklen(addr));
 203
 204         (*v4_incs)++;
 205         return 0;
 206 }
 207
 208 static int appendenv(const char *opt, const char *new)
 209 {
 210         char buf[1024];
 211         char *old = getenv(opt);
 212
 213         buf[1023] = 0;
 214         if (old)
 215                 snprintf(buf, 1023, "%s %s", old, new);
 216         else
 217                 snprintf(buf, 1023, "%s", new);
 218
 219         return setenv(opt, buf, 1);
 220 }
 221
 222 static void setenv_cstp_opts(struct openconnect_info *vpninfo)
 223 {
 224         char *env_buf;
 225         int buflen = 0;
 226         int bufofs = 0;
 227         struct vpn_option *opt;
 228
 229         for (opt = vpninfo->cstp_options; opt; opt = opt->next)
 230                 buflen += 2 + strlen(opt->option) + strlen(opt->value);
 231
 232         env_buf = malloc(buflen + 1);
 233         if (!env_buf)
 234                 return;
 235
 236         env_buf[buflen] = 0;
 237
 238         for (opt = vpninfo->cstp_options; opt; opt = opt->next)
 239                 bufofs += snprintf(env_buf + bufofs, buflen - bufofs,
 240                                    "%s=%s\n", opt->option, opt->value);
 241
 242         setenv("CISCO_CSTP_OPTIONS", env_buf, 1);
 243         free(env_buf);
 244 }
 245
 246 static void set_banner(struct openconnect_info *vpninfo)
 247 {
 248         char *banner, *q;
 249         const char *p;
 250
 251         if (!vpninfo->banner || !(banner = malloc(strlen(vpninfo->banner)))) {
 252                 unsetenv("CISCO_BANNER");
 253                 return;
 254         }
 255         p = vpninfo->banner;
 256         q = banner;
 257
 258         while (*p) {
 259                 if (*p == '%' && isxdigit((int)(unsigned char)p[1]) &&
 260                     isxdigit((int)(unsigned char)p[2])) {
 261                         *(q++) = unhex(p + 1);
 262                         p += 3;
 263                 } else
 264                         *(q++) = *(p++);
 265         }
 266         *q = 0;
 267         setenv("CISCO_BANNER", banner, 1);
 268
 269         free(banner);
 270 }
 271
 272 static void set_script_env(struct openconnect_info *vpninfo)
 273 {
 274         char host[80];
 275         int ret = getnameinfo(vpninfo->peer_addr, vpninfo->peer_addrlen, host,
 276                               sizeof(host), NULL, 0, NI_NUMERICHOST);
 277         if (!ret)
 278                 setenv("VPNGATEWAY", host, 1);
 279
 280         setenv("reason", "connect", 1);
 281         set_banner(vpninfo);
 282         unsetenv("CISCO_SPLIT_INC");
 283         unsetenv("CISCO_SPLIT_EXC");
 284
 285         setenv_int("INTERNAL_IP4_MTU", vpninfo->mtu);
 286
 287         if (vpninfo->vpn_addr) {
 288                 setenv("INTERNAL_IP4_ADDRESS", vpninfo->vpn_addr, 1);
 289                 if (vpninfo->vpn_netmask) {
 290                         struct in_addr addr;
 291                         struct in_addr mask;
 292
 293                         if (inet_aton(vpninfo->vpn_addr, &addr) &&
 294                             inet_aton(vpninfo->vpn_netmask, &mask)) {
 295                                 char *netaddr;
 296
 297                                 addr.s_addr &= mask.s_addr;
 298                                 netaddr = inet_ntoa(addr);
 299
 300                                 setenv("INTERNAL_IP4_NETADDR", netaddr, 1);
 301                                 setenv("INTERNAL_IP4_NETMASK", vpninfo->vpn_netmask, 1);
 302                                 setenv_int("INTERNAL_IP4_NETMASKLEN", netmasklen(mask));
 303                         }
 304                 }
 305         }
 306         if (vpninfo->vpn_addr6) {
 307                 setenv("INTERNAL_IP6_ADDRESS", vpninfo->vpn_addr6, 1);
 308                 setenv("INTERNAL_IP6_NETMASK", vpninfo->vpn_netmask6, 1);
 309         }
 310
 311         if (vpninfo->vpn_dns[0])
 312                 setenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[0], 1);
 313         else
 314                 unsetenv("INTERNAL_IP4_DNS");
 315         if (vpninfo->vpn_dns[1])
 316                 appendenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[1]);
 317         if (vpninfo->vpn_dns[2])
 318                 appendenv("INTERNAL_IP4_DNS", vpninfo->vpn_dns[2]);
 319
 320         if (vpninfo->vpn_nbns[0])
 321                 setenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[0], 1);
 322         else
 323                 unsetenv("INTERNAL_IP4_NBNS");
 324         if (vpninfo->vpn_nbns[1])
 325                 appendenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[1]);
 326         if (vpninfo->vpn_nbns[2])
 327                 appendenv("INTERNAL_IP4_NBNS", vpninfo->vpn_nbns[2]);
 328
 329         if (vpninfo->vpn_domain)
 330                 setenv("CISCO_DEF_DOMAIN", vpninfo->vpn_domain, 1);
 331         else unsetenv ("CISCO_DEF_DOMAIN");
 332
 333         if (vpninfo->vpn_proxy_pac)
 334                 setenv("CISCO_PROXY_PAC", vpninfo->vpn_proxy_pac, 1);
 335
 336         if (vpninfo->split_includes) {
 337                 struct split_include *this = vpninfo->split_includes;
 338                 int nr_split_includes = 0;
 339                 int nr_v6_split_includes = 0;
 340
 341                 while (this) {
 342                         process_split_xxclude(vpninfo, 1, this->route,
 343                                               &nr_split_includes,
 344                                               &nr_v6_split_includes);
 345                         this = this->next;
 346                 }
 347                 if (nr_split_includes)
 348                         setenv_int("CISCO_SPLIT_INC", nr_split_includes);
 349                 if (nr_v6_split_includes)
 350                         setenv_int("CISCO_IPV6_SPLIT_INC", nr_v6_split_includes);
 351         }
 352         if (vpninfo->split_excludes) {
 353                 struct split_include *this = vpninfo->split_excludes;
 354                 int nr_split_excludes = 0;
 355                 int nr_v6_split_excludes = 0;
 356
 357                 while (this) {
 358                         process_split_xxclude(vpninfo, 0, this->route,
 359                                               &nr_split_excludes,
 360                                               &nr_v6_split_excludes);
 361                         this = this->next;
 362                 }
 363                 if (nr_split_excludes)
 364                         setenv_int("CISCO_SPLIT_EXC", nr_split_excludes);
 365                 if (nr_v6_split_excludes)
 366                         setenv_int("CISCO_IPV6_SPLIT_EXC", nr_v6_split_excludes);
 367         }
 368         setenv_cstp_opts(vpninfo);
 369 }
 370
 371 static int script_config_tun(struct openconnect_info *vpninfo)
 372 {
 373         if (system(vpninfo->vpnc_script)) {
 374                 int e = errno;
 375                 vpn_progress(vpninfo, PRG_ERR,
 376                              _("Failed to spawn script '%s': %s\n"),
 377                              vpninfo->vpnc_script, strerror(e));
 378                 return -e;
 379         }
 380         return 0;
 381 }
 382
 383 void script_reconnect (struct openconnect_info *vpninfo)
 384 {
 385         setenv("reason", "reconnect", 1);
 386         script_config_tun(vpninfo);
 387 }
 388
 389 #ifdef __sun__
 390 static int link_proto(int unit_nr, const char *devname, uint64_t flags)
 391 {
 392         int ip_fd, mux_id, tun2_fd;
 393         struct lifreq ifr;
 394
 395         tun2_fd = open("/dev/tun", O_RDWR);
 396         if (tun2_fd < 0) {
 397                 perror(_("Could not /dev/tun for plumbing"));
 398                 return -EIO;
 399         }
 400         if (ioctl(tun2_fd, I_PUSH, "ip") < 0) {
 401                 perror(_("Can't push IP"));
 402                 close(tun2_fd);
 403                 return -EIO;
 404         }
 405
 406         sprintf(ifr.lifr_name, "tun%d", unit_nr);
 407         ifr.lifr_ppa = unit_nr;
 408         ifr.lifr_flags = flags;
 409
 410         if (ioctl(tun2_fd, SIOCSLIFNAME, &ifr) < 0) {
 411                 perror(_("Can't set ifname"));
 412                 close(tun2_fd);
 413                 return -1;
 414         }
 415
 416         ip_fd = open(devname, O_RDWR);
 417         if (ip_fd < 0) {
 418                 fprintf(stderr, _("Can't open %s: %s"), devname,
 419                         strerror(errno));
 420                 close(tun2_fd);
 421                 return -1;
 422         }
 423         if (ioctl(ip_fd, I_PUSH, "arp") < 0) {
 424                 perror(_("Can't push ARP"));
 425                 close(tun2_fd);
 426                 close(ip_fd);
 427                 return -1;
 428         }
 429
 430         mux_id = ioctl(ip_fd, I_LINK, tun2_fd);
 431         if (mux_id < 0) {
 432                 fprintf(stderr, _("Can't plumb %s for IPv%d: %s\n"),
 433                          ifr.lifr_name, (flags == IFF_IPV4) ? 4 : 6,
 434                          strerror(errno));
 435                 close(tun2_fd);
 436                 close(ip_fd);
 437                 return -1;
 438         }
 439
 440         close(tun2_fd);
 441
 442         return ip_fd;
 443 }
 444 #endif
 445 /* Set up a tuntap device. */
 446 int setup_tun(struct openconnect_info *vpninfo)
 447 {
 448         int tun_fd;
 449
 450         set_script_env(vpninfo);
 451
 452         if (vpninfo->script_tun) {
 453                 pid_t child;
 454                 int fds[2];
 455
 456                 if (socketpair(AF_UNIX, SOCK_DGRAM, 0, fds)) {
 457                         perror(_("socketpair"));
 458                         exit(1);
 459                 }
 460                 tun_fd = fds[0];
 461                 child = fork();
 462                 if (child < 0) {
 463                         perror(_("fork"));
 464                         exit(1);
 465                 } else if (!child) {
 466                         close(tun_fd);
 467                         setenv_int("VPNFD", fds[1]);
 468                         execl("/bin/sh", "/bin/sh", "-c", vpninfo->vpnc_script, NULL);
 469                         perror(_("execl"));
 470                         exit(1);
 471                 }
 472                 close(fds[1]);
 473                 vpninfo->script_tun = child;
 474                 vpninfo->ifname = strdup(_("(script)"));
 475         } else {
 476 #ifdef IFF_TUN /* Linux */
 477                 struct ifreq ifr;
 478                 int tunerr;
 479
 480                 tun_fd = open("/dev/net/tun", O_RDWR);
 481                 if (tun_fd < 0) {
 482                         /* Android has /dev/tun instead of /dev/net/tun
 483                            Since other systems might have too, just try it
 484                            as a fallback instead of using ifdef __ANDROID__ */
 485                         tunerr = errno;
 486                         tun_fd = open("/dev/tun", O_RDWR);
 487                 }
 488                 if (tun_fd < 0) {
 489                         /* If the error on /dev/tun is ENOENT, that's boring.
 490                            Use the error we got on /dev/net/tun instead */
 491                         if (errno != -ENOENT)
 492                                 tunerr = errno;
 493
 494                         vpn_progress(vpninfo, PRG_ERR,
 495                                      _("Failed to open tun device: %s\n"),
 496                                      strerror(tunerr));
 497                         exit(1);
 498                 }
 499                 memset(&ifr, 0, sizeof(ifr));
 500                 ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
 501                 if (vpninfo->ifname)
 502                         strncpy(ifr.ifr_name, vpninfo->ifname,
 503                                 sizeof(ifr.ifr_name) - 1);
 504                 if (ioctl(tun_fd, TUNSETIFF, (void *) &ifr) < 0) {
 505                         vpn_progress(vpninfo, PRG_ERR,
 506                                      _("TUNSETIFF failed: %s\n"),
 507                                      strerror(errno));
 508                         exit(1);
 509                 }
 510                 if (!vpninfo->ifname)
 511                         vpninfo->ifname = strdup(ifr.ifr_name);
 512 #elif defined (__sun__)
 513                 static char tun_name[80];
 514                 int unit_nr;
 515
 516                 tun_fd = open("/dev/tun", O_RDWR);
 517                 if (tun_fd < 0) {
 518                         perror(_("open /dev/tun"));
 519                         return -EIO;
 520                 }
 521
 522                 unit_nr = ioctl(tun_fd, TUNNEWPPA, -1);
 523                 if (unit_nr < 0) {
 524                         perror(_("Failed to create new tun"));
 525                         close(tun_fd);
 526                         return -EIO;
 527                 }
 528
 529                 if (ioctl(tun_fd, I_SRDOPT, RMSGD) < 0) {
 530                         perror(_("Failed to put tun file descriptor into message-discard mode"));
 531                         close(tun_fd);
 532                         return -EIO;
 533                 }
 534
 535                 sprintf(tun_name, "tun%d", unit_nr);
 536                 vpninfo->ifname = strdup(tun_name);
 537
 538                 vpninfo->ip_fd = link_proto(unit_nr, "/dev/udp", IFF_IPV4);
 539                 if (vpninfo->ip_fd < 0) {
 540                         close(tun_fd);
 541                         return -EIO;
 542                 }
 543
 544                 if (vpninfo->vpn_addr6) {
 545                         vpninfo->ip6_fd = link_proto(unit_nr, "/dev/udp6", IFF_IPV6);
 546                         if (vpninfo->ip6_fd < 0) {
 547                                 close(tun_fd);
 548                                 close(vpninfo->ip_fd);
 549                                 vpninfo->ip_fd = -1;
 550                                 return -EIO;
 551                         }
 552                 } else
 553                         vpninfo->ip6_fd = -1;
 554
 555 #else /* BSD et al have /dev/tun$x devices */
 556                 static char tun_name[80];
 557                 int i;
 558                 for (i = 0; i < 255; i++) {
 559                         sprintf(tun_name, "/dev/tun%d", i);
 560                         tun_fd = open(tun_name, O_RDWR);
 561                         if (tun_fd >= 0)
 562                                 break;
 563                 }
 564                 if (tun_fd < 0) {
 565                         perror(_("open tun"));
 566                         exit(1);
 567                 }
 568                 vpninfo->ifname = strdup(tun_name + 5);
 569 #ifdef TUNSIFHEAD
 570                 i = 1;
 571                 if (ioctl(tun_fd, TUNSIFHEAD, &i) < 0) {
 572                         perror(_("TUNSIFHEAD"));
 573                         exit(1);
 574                 }
 575 #endif
 576 #endif
 577                 if (vpninfo->vpnc_script) {
 578                         setenv("TUNDEV", vpninfo->ifname, 1);
 579                         script_config_tun(vpninfo);
 580                         /* We have to set the MTU for ourselves, because the script doesn't */
 581                         local_config_tun(vpninfo, 1);
 582                 } else
 583                         local_config_tun(vpninfo, 0);
 584         }
 585
 586         fcntl(tun_fd, F_SETFD, FD_CLOEXEC);
 587
 588         vpninfo->tun_fd = tun_fd;
 589
 590         if (vpninfo->select_nfds <= tun_fd)
 591                 vpninfo->select_nfds = tun_fd + 1;
 592
 593         FD_SET(tun_fd, &vpninfo->select_rfds);
 594
 595         fcntl(vpninfo->tun_fd, F_SETFL, fcntl(vpninfo->tun_fd, F_GETFL) | O_NONBLOCK);
 596
 597         return 0;
 598 }
 599
 600 static struct pkt *out_pkt;
 601
 602 int tun_mainloop(struct openconnect_info *vpninfo, int *timeout)
 603 {
 604         int work_done = 0;
 605         int prefix_size = 0;
 606
 607 #ifdef TUN_HAS_AF_PREFIX
 608         if (!vpninfo->script_tun)
 609                 prefix_size = sizeof(int);
 610 #endif
 611
 612         if (FD_ISSET(vpninfo->tun_fd, &vpninfo->select_rfds)) {
 613                 while (1) {
 614                         int len = vpninfo->mtu;
 615
 616                         if (!out_pkt) {
 617                                 out_pkt = malloc(sizeof(struct pkt) + len);
 618                                 if (!out_pkt) {
 619                                         vpn_progress(vpninfo, PRG_ERR, "Allocation failed\n");
 620                                         break;
 621                                 }
 622                         }
 623
 624                         len = read(vpninfo->tun_fd, out_pkt->data - prefix_size, len + prefix_size);
 625                         if (len <= prefix_size)
 626                                 break;
 627                         out_pkt->len = len - prefix_size;
 628
 629                         queue_packet(&vpninfo->outgoing_queue, out_pkt);
 630                         out_pkt = NULL;
 631
 632                         work_done = 1;
 633                         vpninfo->outgoing_qlen++;
 634                         if (vpninfo->outgoing_qlen == vpninfo->max_qlen) {
 635                                 FD_CLR(vpninfo->tun_fd, &vpninfo->select_rfds);
 636                                 break;
 637                         }
 638                 }
 639         } else if (vpninfo->outgoing_qlen < vpninfo->max_qlen) {
 640                 FD_SET(vpninfo->tun_fd, &vpninfo->select_rfds);
 641         }
 642
 643         /* The kernel returns -ENOMEM when the queue is full, so theoretically
 644            we could handle that and retry... but it doesn't let us poll() for
 645            the no-longer-full situation, so let's not bother. */
 646         while (vpninfo->incoming_queue) {
 647                 struct pkt *this = vpninfo->incoming_queue;
 648                 unsigned char *data = this->data;
 649                 int len = this->len;
 650
 651 #ifdef TUN_HAS_AF_PREFIX
 652                 if (!vpninfo->script_tun) {
 653                         struct ip *iph = (void *)data;
 654                         int type;
 655
 656                         if (iph->ip_v == 6)
 657                                 type = AF_INET6;
 658                         else if (iph->ip_v == 4)
 659                                 type = AF_INET;
 660                         else {
 661                                 static int complained = 0;
 662                                 if (!complained) {
 663                                         complained = 1;
 664                                         vpn_progress(vpninfo, PRG_ERR,
 665                                                      _("Unknown packet (len %d) received: %02x %02x %02x %02x...\n"),
 666                                                      len, data[0], data[1], data[2], data[3]);
 667                                 }
 668                                 free(this);
 669                                 continue;
 670                         }
 671                         data -= 4;
 672                         len += 4;
 673                         *(int *)data = htonl(type);
 674                 }
 675 #endif
 676                 vpninfo->incoming_queue = this->next;
 677
 678                 if (write(vpninfo->tun_fd, data, len) < 0) {
 679                         /* Handle death of "script" socket */
 680                         if (vpninfo->script_tun && errno == ENOTCONN) {
 681                                 vpninfo->quit_reason = "Client connection terminated";
 682                                 return 1;
 683                         }
 684                         vpn_progress(vpninfo, PRG_ERR,
 685                                      _("Failed to write incoming packet: %s\n"),
 686                                      strerror(errno));
 687                 }
 688                 free(this);
 689         }
 690         /* Work is not done if we just got rid of packets off the queue */
 691         return work_done;
 692 }
 693
 694 void shutdown_tun(struct openconnect_info *vpninfo)
 695 {
 696         if (vpninfo->script_tun) {
 697                 kill(vpninfo->script_tun, SIGHUP);
 698         } else {
 699                 if (vpninfo->vpnc_script) {
 700                         setenv("reason", "disconnect", 1);
 701                         if (system(vpninfo->vpnc_script) == -1) {
 702                                 vpn_progress(vpninfo, PRG_ERR,
 703                                              _("Failed to spawn script '%s': %s\n"),
 704                                              vpninfo->vpnc_script,
 705                                              strerror(errno));
 706                         }
 707                 }
 708 #ifdef __sun__
 709                 close(vpninfo->ip_fd);
 710                 vpninfo->ip_fd = -1;
 711                 if (vpninfo->ip6_fd != -1) {
 712                         close(vpninfo->ip6_fd);
 713                         vpninfo->ip6_fd = -1;
 714                 }
 715 #endif
 716         }
 717
 718         close(vpninfo->tun_fd);
 719         vpninfo->tun_fd = -1;
 720 }