mdw@git.distorted.org.uk Git - tripe/blob - server/tripe.c

   1 /* -*-c-*-
   2  *
   3  * Main program
   4  *
   5  * (c) 2001 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Trivial IP Encryption (TrIPE).
  11  *
  12  * TrIPE is free software: you can redistribute it and/or modify it under
  13  * the terms of the GNU General Public License as published by the Free
  14  * Software Foundation; either version 3 of the License, or (at your
  15  * option) any later version.
  16  *
  17  * TrIPE is distributed in the hope that it will be useful, but WITHOUT
  18  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  19  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  20  * for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with TrIPE.  If not, see <https://www.gnu.org/licenses/>.
  24  */
  25
  26 /*----- Header files ------------------------------------------------------*/
  27
  28 #include "tripe.h"
  29
  30 /*----- Global variables --------------------------------------------------*/
  31
  32 sel_state sel;
  33
  34 /*----- Static variables --------------------------------------------------*/
  35
  36 static sel_timer it;
  37 #define T_INTERVAL MIN(1)
  38
  39 static unsigned iv_nreasons = 0;
  40 static struct timeval iv_next = { 0, 0 };
  41
  42 /*----- The interval timer ------------------------------------------------*/
  43
  44 /* --- @interval@ --- *
  45  *
  46  * Arguments:   @struct timeval *tv@ = time when called
  47  *              @void *v@ = boring pointer
  48  *
  49  * Returns:     ---
  50  *
  51  * Use:         Called periodically to do housekeeping tasks.
  52  */
  53
  54 static void interval(struct timeval *tv, void *v)
  55 {
  56   T( trace(T_PEER, "peer: interval timer"); )
  57   iv_next = *tv;
  58   rand_seed(RAND_GLOBAL, MAXHASHSZ);
  59   p_interval();
  60   iv_next.tv_sec += T_INTERVAL;
  61   sel_addtimer(&sel, &it, &iv_next, interval, v);
  62 }
  63
  64 /* --- @iv_addreason@ --- *
  65  *
  66  * Arguments:   ---
  67  *
  68  * Returns:     ---
  69  *
  70  * Use:         Adds an `interval timer reason'; if there are no others, the
  71  *              interval timer is engaged.
  72  */
  73
  74 void iv_addreason(void)
  75 {
  76   struct timeval tv;
  77
  78   if (!iv_nreasons) {
  79     gettimeofday(&tv, 0);
  80     if (TV_CMP(&tv, >=, &iv_next)) interval(&tv, 0);
  81     else sel_addtimer(&sel, &it, &iv_next, interval, 0);
  82   }
  83   iv_nreasons++;
  84 }
  85
  86 /* --- @iv_rmreason@ --- *
  87  *
  88  * Arguments:   ---
  89  *
  90  * Returns:     ---
  91  *
  92  * Use:         Removes an interval timer reason; if there are none left, the
  93  *              interval timer is disengaged.
  94  */
  95
  96 void iv_rmreason(void)
  97 {
  98   assert(iv_nreasons); iv_nreasons--;
  99   if (!iv_nreasons) sel_rmtimer(&it);
 100 }
 101
 102 /*----- Main code ---------------------------------------------------------*/
 103
 104 /* --- @main@ --- *
 105  *
 106  * Arguments:   @int argc@ = number of command line arguments
 107  *              @char *argv[]@ = vector of arguments
 108  *
 109  * Returns:     Zero if OK, nonzero on error.
 110  *
 111  * Use:         Main program.  Provides a simple VPN.
 112  */
 113
 114 static void usage(FILE *fp)
 115 {
 116   pquis(fp, "Usage: $ [-DF] [-d DIR] [-b ADDR] [-p PORT] [-n TUNNEL]\n\
 117         [-U USER] [-G GROUP] [-a SOCKET] [-m MODE] [-T TRACE-OPTS]\n\
 118         [-k PRIV-KEYRING] [-K PUB-KEYRING] [-t KEY-TAG]\n");
 119 }
 120
 121 static void version(FILE *fp) { pquis(fp, "$, version " VERSION "\n"); }
 122
 123 static void help(FILE *fp)
 124 {
 125   version(fp);
 126   fputc('\n', fp);
 127   usage(fp);
 128   fputs("\n\
 129 Options:\n\
 130 \n\
 131 -h, --help              Display this help text.\n\
 132 -v, --version           Display version number.\n\
 133 -u, --usage             Display pointless usage message.\n\
 134     --tunnels           Display IP tunnel drivers and exit.\n\
 135 \n\
 136 -4, --ipv4              Transport over IPv4 only.\n\
 137 -6, --ipv6              Transport over IPv6 only.\n\
 138 -D, --daemon            Run in the background.\n\
 139 -F, --foreground        Quit when stdin reports end-of-file.\n\
 140 -d, --directory=DIR     Switch to directory DIR [default " CONFIGDIR "].\n\
 141 -b, --bind-address=ADDR Bind UDP socket to this IP ADDR.\n\
 142 -p, --port=PORT         Select UDP port to listen to "
 143         "[default " STR(TRIPE_PORT) "].\n\
 144 -n, --tunnel=TUNNEL     Seelect default tunnel driver.\n\
 145 -U, --setuid=USER       Set uid to USER after initialization.\n\
 146 -G, --setgid=GROUP      Set gid to GROUP after initialization.\n\
 147 -k, --priv-keyring=FILE Get private key from FILE.\n\
 148 -K, --pub-keyring=FILE  Get public keys from FILE.\n\
 149 -t, --tag=KEYTAG        Use private key labelled TAG.\n\
 150 -a, --admin-socket=FILE Use FILE as the adminstration socket.\n\
 151 -m, --admin-perms=MODE  Permissions to set on admin socket [default 600].\n\
 152 " T( "\
 153 -T, --trace=OPTIONS     Turn on tracing options.\n\
 154 " ) "\
 155 ", fp);
 156 }
 157
 158 int main(int argc, char *argv[])
 159 {
 160   const char *kr_priv = "keyring", *kr_pub = "keyring.pub";
 161   const char *tag_priv = 0;
 162   const char *csock = SOCKETDIR "/tripesock";
 163   int csockmode = 0600;
 164   const char *dir = CONFIGDIR;
 165   const char *p;
 166   const char *bindhost = 0, *bindsvc = STR(TRIPE_PORT);
 167   struct addrinfo aihint = { 0 }, *ailist;
 168   unsigned f = 0;
 169   int i;
 170   int err, selerr = 0;
 171   unsigned af;
 172   uid_t u = -1;
 173   gid_t g = -1;
 174
 175 #define f_bogus 1u
 176 #define f_daemon 2u
 177 #define f_foreground 4u
 178
 179   ego(argv[0]);
 180   T( trace_on(stderr, 0); )
 181
 182   if ((p = getenv("TRIPEDIR")) != 0)
 183     dir = p;
 184   if ((p = getenv("TRIPESOCK")) != 0)
 185     csock = p;
 186   tun_default = tunnels[0];
 187   aihint.ai_family = AF_UNSPEC;
 188
 189   for (;;) {
 190     static const struct option opts[] = {
 191       { "help",         0,              0,      'h' },
 192       { "version",      0,              0,      'v' },
 193       { "usage",        0,              0,      'u' },
 194       { "tunnels",      0,              0,      '0' },
 195
 196       { "ipv4",         0,              0,      '4' },
 197       { "ipv6",         0,              0,      '6' },
 198       { "daemon",       0,              0,      'D' },
 199       { "foreground",   0,              0,      'F' },
 200       { "uid",          OPTF_ARGREQ,    0,      'U' },
 201       { "setuid",       OPTF_ARGREQ,    0,      'U' },
 202       { "gid",          OPTF_ARGREQ,    0,      'G' },
 203       { "setgid",       OPTF_ARGREQ,    0,      'G' },
 204       { "bind-address", OPTF_ARGREQ,    0,      'b' },
 205       { "tunnel",       OPTF_ARGREQ,    0,      'n' },
 206       { "port",         OPTF_ARGREQ,    0,      'p' },
 207       { "directory",    OPTF_ARGREQ,    0,      'd' },
 208       { "priv-keyring", OPTF_ARGREQ,    0,      'k' },
 209       { "pub-keyring",  OPTF_ARGREQ,    0,      'K' },
 210       { "tag",          OPTF_ARGREQ,    0,      't' },
 211       { "admin-socket", OPTF_ARGREQ,    0,      'a' },
 212       { "admin-perms",  OPTF_ARGREQ,    0,      'm' },
 213 #ifndef NTRACE
 214       { "trace",        OPTF_ARGREQ,    0,      'T' },
 215 #endif
 216
 217       { 0,              0,              0,      0 }
 218     };
 219
 220     i = mdwopt(argc, argv, "hvu46DFU:G:b:n:p:d:k:K:t:a:m:" T("T:"),
 221                opts, 0, 0, 0);
 222     if (i < 0)
 223       break;
 224     switch (i) {
 225       case 'h':
 226         help(stdout);
 227         exit(0);
 228       case 'v':
 229         version(stdout);
 230         exit(0);
 231       case 'u':
 232         usage(stdout);
 233         exit(0);
 234
 235       case '4':
 236         aihint.ai_family = AF_INET;
 237         break;
 238       case '6':
 239         aihint.ai_family = AF_INET6;
 240         break;
 241       case 'D':
 242         f |= f_daemon;
 243         break;
 244       case 'U':
 245         u = u_getuser(optarg, &g);
 246         break;
 247       case 'G':
 248         g = u_getgroup(optarg);
 249         break;
 250       case 'F':
 251         f |= f_foreground;
 252         break;
 253
 254       case 'b':
 255         bindhost = optarg;
 256         break;
 257       case 'p':
 258         bindsvc = optarg;
 259         break;
 260       case 'n': {
 261         int i;
 262         for (i = 0;; i++) {
 263           if (!tunnels[i])
 264             die(EXIT_FAILURE, "unknown tunnel `%s'", optarg);
 265           if (mystrieq(optarg, tunnels[i]->name))
 266             break;
 267         }
 268         tun_default = tunnels[i];
 269       } break;
 270       case 'd':
 271         dir = optarg;
 272         break;
 273       case 'k':
 274         kr_priv = optarg;
 275         break;
 276       case 'K':
 277         kr_pub = optarg;
 278         break;
 279       case 'a':
 280         csock = optarg;
 281         break;
 282       case 'm': {
 283         char *p;
 284         csockmode = strtol(optarg, &p, 8);
 285         if (*p) die(EXIT_FAILURE, "bad permissions: `%s'", optarg);
 286       } break;
 287       case 't':
 288         tag_priv = optarg;
 289         break;
 290 #ifndef NTRACE
 291       case 'T':
 292         tr_flags = traceopt(tr_opts, optarg, tr_flags, 0);
 293         trace_level(tr_flags);
 294         break;
 295 #endif
 296       case '0': {
 297         int i;
 298         for (i = 0; tunnels[i]; i++)
 299           puts(tunnels[i]->name);
 300         exit(0);
 301       } break;
 302       default:
 303         f |= f_bogus;
 304         break;
 305     }
 306   }
 307
 308   if (optind < argc || (f & f_bogus)) {
 309     usage(stderr);
 310     exit(EXIT_FAILURE);
 311   }
 312   if (!(~f & (f_daemon | f_foreground)))
 313     die(EXIT_FAILURE, "foreground operation for a daemon is silly");
 314
 315   aihint.ai_protocol = IPPROTO_UDP;
 316   aihint.ai_socktype = SOCK_DGRAM;
 317   aihint.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
 318   if ((err = getaddrinfo(bindhost, bindsvc, &aihint, &ailist)) != 0) {
 319     die(EXIT_FAILURE, "couldn't resolve hostname %c%s%c, port `%s': %s",
 320         bindhost ? '`' : '<',
 321         bindhost ? bindhost : "nil",
 322         bindhost ? '\'' : '>',
 323         bindsvc, gai_strerror(err));
 324   }
 325
 326   if (chdir(dir)) {
 327     die(EXIT_FAILURE, "can't set current directory to `%s': %s",
 328         dir, strerror(errno));
 329   }
 330
 331   sel_init(&sel);
 332   sig_init(&sel);
 333   rand_noisesrc(RAND_GLOBAL, &noise_source);
 334   rand_seed(RAND_GLOBAL, MAXHASHSZ);
 335   signal(SIGPIPE, SIG_IGN);
 336
 337   if (!(f & f_daemon)) {
 338     af = AF_WARN;
 339 #ifndef NTRACE
 340     af |= AF_TRACE;
 341 #endif
 342     if (f & f_foreground)
 343       af |= AF_FOREGROUND;
 344     a_create(STDIN_FILENO, STDOUT_FILENO, af);
 345     a_switcherr();
 346   }
 347
 348   p_init();
 349   for (i = 0; tunnels[i]; i++)
 350     tunnels[i]->init();
 351   p_bind(ailist); freeaddrinfo(ailist);
 352
 353   for (i = 0; tunnels[i]; i++) {
 354     if (tunnels[i]->flags&TUNF_PRIVOPEN) {
 355       ps_split(f & f_daemon);
 356       break;
 357     }
 358   }
 359
 360   a_init();
 361   a_signals();
 362   a_listen(csock, u, g, csockmode);
 363   u_setugid(u, g);
 364   km_init(kr_priv, kr_pub, tag_priv);
 365   kx_init();
 366   if (f & f_daemon) {
 367     if (daemonize()) {
 368       a_warn("SERVER", "daemon-error", "?ERRNO", A_END);
 369       exit(EXIT_FAILURE);
 370     }
 371     a_daemon();
 372     a_switcherr();
 373   }
 374
 375   gettimeofday(&iv_next, 0); iv_next.tv_sec += T_INTERVAL;
 376   iv_addreason();
 377
 378   for (;;) {
 379     a_preselect();
 380     if (!sel_select(&sel))
 381       selerr = 0;
 382     else if (errno != EINTR && errno != EAGAIN) {
 383       a_warn("SERVER", "select-error", "?ERRNO", A_END);
 384       selerr++;
 385       if (selerr > 8) {
 386         a_warn("ABORT", "repeated-select-errors", A_END);
 387         abort();
 388       }
 389     }
 390   }
 391
 392   return (0);
 393 }
 394
 395 /*----- That's all, folks -------------------------------------------------*/