src/or/router.c

   1 /* Copyright 2001,2002,2003 Roger Dingledine, Matej Pfajfar. */
   2 /* See LICENSE for licensing information */
   3 /* $Id$ */
   4
   5 #include "or.h"
   6
   7 extern or_options_t options; /* command-line and config-file options */
   8
   9 /************************************************************/
  10
  11 /* private keys */
  12 static crypto_pk_env_t *onionkey=NULL;
  13 static crypto_pk_env_t *linkkey=NULL;
  14 static crypto_pk_env_t *identitykey=NULL;
  15
  16 void set_onion_key(crypto_pk_env_t *k) {
  17   onionkey = k;
  18 }
  19
  20 crypto_pk_env_t *get_onion_key(void) {
  21   assert(onionkey);
  22   return onionkey;
  23 }
  24
  25 void set_link_key(crypto_pk_env_t *k)
  26 {
  27   linkkey = k;
  28 }
  29
  30 crypto_pk_env_t *get_link_key(void)
  31 {
  32   assert(linkkey);
  33   return linkkey;
  34 }
  35
  36 void set_identity_key(crypto_pk_env_t *k) {
  37   identitykey = k;
  38 }
  39
  40 crypto_pk_env_t *get_identity_key(void) {
  41   assert(identitykey);
  42   return identitykey;
  43 }
  44
  45 /************************************************************/
  46
  47 static crypto_pk_env_t *init_key_from_file(const char *fname)
  48 {
  49   crypto_pk_env_t *prkey = NULL;
  50   int fd = -1;
  51   FILE *file = NULL;
  52
  53   if (!(prkey = crypto_new_pk_env(CRYPTO_PK_RSA))) {
  54     log(LOG_ERR, "Error creating crypto environment.");
  55     goto error;
  56   }
  57
  58   switch(file_status(fname)) {
  59   case FN_DIR:
  60   case FN_ERROR:
  61     log(LOG_ERR, "Can't read key from %s", fname);
  62     goto error;
  63   case FN_NOENT:
  64     log(LOG_INFO, "No key found in %s; generating fresh key.", fname);
  65     if (crypto_pk_generate_key(prkey)) {
  66       log(LOG_ERR, "Error generating key: %s", crypto_perror());
  67       goto error;
  68     }
  69     if (crypto_pk_check_key(prkey) <= 0) {
  70       log(LOG_ERR, "Generated key seems invalid");
  71       goto error;
  72     }
  73     log(LOG_INFO, "Generated key seems valid");
  74     if (crypto_pk_write_private_key_to_filename(prkey, fname)) {
  75       log(LOG_ERR, "Couldn't write generated key to %s.", fname);
  76       goto error;
  77     }
  78     return prkey;
  79   case FN_FILE:
  80     if (crypto_pk_read_private_key_from_filename(prkey, fname)) {
  81       log(LOG_ERR, "Error loading private key.");
  82       goto error;
  83     }
  84     return prkey;
  85   default:
  86     assert(0);
  87   }
  88
  89  error:
  90   if (prkey)
  91     crypto_free_pk_env(prkey);
  92   if (fd >= 0 && !file)
  93     close(fd);
  94   if (file)
  95     fclose(file);
  96   return NULL;
  97 }
  98
  99 int init_keys(void) {
 100   char keydir[512];
 101   char fingerprint[FINGERPRINT_LEN+MAX_NICKNAME_LEN+3];
 102   char *cp;
 103   const char *tmp, *mydesc;
 104   crypto_pk_env_t *prkey;
 105
 106   /* OP's don't need keys.  Just initialize the TLS context.*/
 107   if (!options.ORPort) {
 108     assert(!options.DirPort);
 109     if (tor_tls_context_new(NULL, 0, NULL)<0) {
 110       log_fn(LOG_ERR, "Error creating TLS context for OP.");
 111       return -1;
 112     }
 113     return 0;
 114   }
 115   assert(options.DataDirectory);
 116   if (strlen(options.DataDirectory) > (512-128)) {
 117     log_fn(LOG_ERR, "DataDirectory is too long.");
 118     return -1;
 119   }
 120   if (check_private_dir(options.DataDirectory, 1)) {
 121     return -1;
 122   }
 123   sprintf(keydir,"%s/keys",options.DataDirectory);
 124   if (check_private_dir(keydir, 1)) {
 125     return -1;
 126   }
 127   cp = keydir + strlen(keydir); /* End of string. */
 128
 129   /* 1. Read identity key. Make it if none is found. */
 130   strcpy(cp, "/identity.key");
 131   log_fn(LOG_INFO,"Reading/making identity key %s...",keydir);
 132   prkey = init_key_from_file(keydir);
 133   if (!prkey) return -1;
 134   set_identity_key(prkey);
 135   /* 2. Read onion key.  Make it if none is found. */
 136   strcpy(cp, "/onion.key");
 137   log_fn(LOG_INFO,"Reading/making onion key %s...",keydir);
 138   prkey = init_key_from_file(keydir);
 139   if (!prkey) return -1;
 140   set_onion_key(prkey);
 141
 142   /* 3. Initialize link key and TLS context. */
 143   strcpy(cp, "/link.key");
 144   log_fn(LOG_INFO,"Reading/making link key %s...",keydir);
 145   prkey = init_key_from_file(keydir);
 146   if (!prkey) return -1;
 147   set_link_key(prkey);
 148   if (tor_tls_context_new(prkey, 1, options.Nickname) < 0) {
 149     log_fn(LOG_ERR, "Error initializing TLS context");
 150     return -1;
 151   }
 152   /* 4. Dump router descriptor to 'router.desc' */
 153   /* Must be called after keys are initialized. */
 154   if (!(router_get_my_descriptor())) {
 155     log_fn(LOG_ERR, "Error initializing descriptor.");
 156     return -1;
 157   }
 158   /* We need to add our own fingerprint so it gets recognized. */
 159   if (dirserv_add_own_fingerprint(options.Nickname, get_identity_key())) {
 160     log_fn(LOG_ERR, "Error adding own fingerprint to approved set");
 161     return -1;
 162   }
 163   tmp = mydesc = router_get_my_descriptor();
 164   if (dirserv_add_descriptor(&tmp)) {
 165     log(LOG_ERR, "Unable to add own descriptor to directory.");
 166     return -1;
 167   }
 168   sprintf(keydir,"%s/router.desc", options.DataDirectory);
 169   log_fn(LOG_INFO,"Dumping descriptor to %s...",keydir);
 170   if (write_str_to_file(keydir, mydesc)) {
 171     return -1;
 172   }
 173   /* 5. Dump fingerprint to 'fingerprint' */
 174   sprintf(keydir,"%s/fingerprint", options.DataDirectory);
 175   log_fn(LOG_INFO,"Dumping fingerprint to %s...",keydir);
 176   assert(strlen(options.Nickname) <= MAX_NICKNAME_LEN);
 177   strcpy(fingerprint, options.Nickname);
 178   strcat(fingerprint, " ");
 179   if (crypto_pk_get_fingerprint(get_identity_key(),
 180                                 fingerprint+strlen(fingerprint))<0) {
 181     log_fn(LOG_ERR, "Error computing fingerprint");
 182     return -1;
 183   }
 184   strcat(fingerprint, "\n");
 185   if (write_str_to_file(keydir, fingerprint))
 186     return -1;
 187   if(!options.DirPort)
 188     return 0;
 189   /* 6. [dirserver only] load approved-routers file */
 190   sprintf(keydir,"%s/approved-routers", options.DataDirectory);
 191   log_fn(LOG_INFO,"Loading approved fingerprints from %s...",keydir);
 192   if(dirserv_parse_fingerprint_file(keydir) < 0) {
 193     log_fn(LOG_ERR, "Error loading fingerprints");
 194     return -1;
 195   }
 196   /* 7. [dirserver only] load old directory, if it's there */
 197   sprintf(keydir,"%s/cached-directory", options.DataDirectory);
 198   log_fn(LOG_INFO,"Loading cached directory from %s...",keydir);
 199   cp = read_file_to_str(keydir);
 200   if(!cp) {
 201     log_fn(LOG_INFO,"Cached directory %s not present. Ok.",keydir);
 202   } else {
 203     if(dirserv_init_from_directory_string(cp) < 0) {
 204       log_fn(LOG_ERR, "Cached directory %s is corrupt", keydir);
 205       free(cp);
 206       return -1;
 207     }
 208     free(cp);
 209   }
 210   /* success */
 211   return 0;
 212 }
 213
 214 /************************************************************/
 215
 216 static routerinfo_t *desc_routerinfo = NULL; /* my descriptor */
 217 static char descriptor[8192]; /* string representation of my descriptor */
 218
 219 void router_retry_connections(void) {
 220   int i;
 221   routerinfo_t *router;
 222   routerlist_t *rl;
 223
 224   router_get_routerlist(&rl);
 225   for (i=0;i<rl->n_routers;i++) {
 226     router = rl->routers[i];
 227     if(!connection_exact_get_by_addr_port(router->addr,router->or_port)) {
 228       /* not in the list */
 229       log_fn(LOG_DEBUG,"connecting to OR %s:%u.",router->address,router->or_port);
 230       connection_or_connect(router);
 231     }
 232   }
 233 }
 234
 235 void router_upload_desc_to_dirservers(void) {
 236   int i;
 237   routerinfo_t *router;
 238   routerlist_t *rl;
 239
 240   router_get_routerlist(&rl);
 241   if(!rl)
 242     return;
 243
 244   if (!router_get_my_descriptor()) {
 245     log_fn(LOG_WARN, "No descriptor; skipping upload");
 246     return;
 247   }
 248
 249   for(i=0;i<rl->n_routers;i++) {
 250     router = rl->routers[i];
 251     if(router->dir_port > 0)
 252       directory_initiate_command(router, DIR_CONN_STATE_CONNECTING_UPLOAD);
 253   }
 254 }
 255
 256 static void router_add_exit_policy_from_config(routerinfo_t *router) {
 257   char *s = options.ExitPolicy, *e;
 258   int last=0;
 259   char line[1024];
 260
 261   if(!s) {
 262     log_fn(LOG_INFO,"No exit policy configured. Ok.");
 263     return; /* nothing to see here */
 264   }
 265   if(!*s) {
 266     log_fn(LOG_INFO,"Exit policy is empty. Ok.");
 267     return; /* nothing to see here */
 268   }
 269
 270   for(;;) {
 271     e = strchr(s,',');
 272     if(!e) {
 273       last = 1;
 274       strncpy(line,s,1023);
 275     } else {
 276       memcpy(line,s, ((e-s)<1023)?(e-s):1023);
 277       line[e-s] = 0;
 278     }
 279     line[1023]=0;
 280     log_fn(LOG_DEBUG,"Adding new entry '%s'",line);
 281     if(router_add_exit_policy_from_string(router,line) < 0)
 282       log_fn(LOG_WARN,"Malformed exit policy %s; skipping.", line);
 283     if(last)
 284       return;
 285     s = e+1;
 286   }
 287 }
 288
 289 /* Return 0 if my exit policy says to allow connection to conn.
 290  * Else return -1.
 291  */
 292 int router_compare_to_my_exit_policy(connection_t *conn) {
 293   assert(desc_routerinfo);
 294   assert(conn->addr); /* make sure it's resolved to something. this
 295                          way we can't get a 'maybe' below. */
 296
 297   if (router_compare_addr_to_exit_policy(conn->addr, conn->port,
 298                                          desc_routerinfo->exit_policy) == 0)
 299     return 0;
 300   else
 301     return -1;
 302 }
 303
 304 const char *router_get_my_descriptor(void) {
 305   if (!desc_routerinfo) {
 306     if (router_rebuild_descriptor())
 307       return NULL;
 308   }
 309   log_fn(LOG_DEBUG,"my desc is '%s'",descriptor);
 310   return descriptor;
 311 }
 312
 313 int router_rebuild_descriptor(void) {
 314   routerinfo_t *ri;
 315   char localhostname[256];
 316   char *address = options.Address;
 317
 318   if(!address) { /* if not specified in config, we find a default */
 319     if(gethostname(localhostname,sizeof(localhostname)) < 0) {
 320       log_fn(LOG_WARN,"Error obtaining local hostname");
 321       return -1;
 322     }
 323     address = localhostname;
 324     if(!strchr(address,'.')) {
 325       log_fn(LOG_WARN,"fqdn '%s' has only one element. Misconfigured machine?",address);
 326       log_fn(LOG_WARN,"Try setting the Address line in your config file.");
 327       return -1;
 328     }
 329   }
 330   ri = tor_malloc(sizeof(routerinfo_t));
 331   ri->address = tor_strdup(address);
 332   ri->nickname = tor_strdup(options.Nickname);
 333   /* No need to set addr. */
 334   ri->or_port = options.ORPort;
 335   ri->socks_port = options.SocksPort;
 336   ri->dir_port = options.DirPort;
 337   ri->published_on = time(NULL);
 338   ri->onion_pkey = crypto_pk_dup_key(get_onion_key());
 339   ri->link_pkey = crypto_pk_dup_key(get_link_key());
 340   ri->identity_pkey = crypto_pk_dup_key(get_identity_key());
 341   ri->bandwidth = options.TotalBandwidth;
 342   ri->exit_policy = NULL; /* zero it out first */
 343   router_add_exit_policy_from_config(ri);
 344   if (desc_routerinfo)
 345     routerinfo_free(desc_routerinfo);
 346   desc_routerinfo = ri;
 347   if (router_dump_router_to_string(descriptor, 8192, ri, get_identity_key())<0) {
 348     log_fn(LOG_WARN, "Couldn't dump router to string.");
 349     return -1;
 350   }
 351   return 0;
 352 }
 353
 354 static void get_platform_str(char *platform, int len)
 355 {
 356   snprintf(platform, len-1, "Tor %s on %s", VERSION, get_uname());
 357   platform[len-1] = '\0';
 358   return;
 359 }
 360
 361 /* XXX need to audit this thing and count fenceposts. maybe
 362  *     refactor so we don't have to keep asking if we're
 363  *     near the end of maxlen?
 364  */
 365 #define DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
 366 int router_dump_router_to_string(char *s, int maxlen, routerinfo_t *router,
 367                                  crypto_pk_env_t *ident_key) {
 368   char *onion_pkey;
 369   char *link_pkey;
 370   char *identity_pkey;
 371   struct in_addr in;
 372   char platform[256];
 373   char digest[20];
 374   char signature[128];
 375   char published[32];
 376   int onion_pkeylen, link_pkeylen, identity_pkeylen;
 377   int written;
 378   int result=0;
 379   struct exit_policy_t *tmpe;
 380 #ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
 381   char *s_tmp, *s_dup;
 382   const char *cp;
 383   routerinfo_t *ri_tmp;
 384 #endif
 385
 386   get_platform_str(platform, sizeof(platform));
 387
 388   if (crypto_pk_cmp_keys(ident_key, router->identity_pkey)) {
 389     log_fn(LOG_WARN,"Tried to sign a router with a private key that didn't match router's public key!");
 390     return -1;
 391   }
 392
 393   if(crypto_pk_write_public_key_to_string(router->onion_pkey,
 394                                           &onion_pkey,&onion_pkeylen)<0) {
 395     log_fn(LOG_WARN,"write onion_pkey to string failed!");
 396     return -1;
 397   }
 398
 399   if(crypto_pk_write_public_key_to_string(router->identity_pkey,
 400                                           &identity_pkey,&identity_pkeylen)<0) {
 401     log_fn(LOG_WARN,"write identity_pkey to string failed!");
 402     return -1;
 403   }
 404
 405   if(crypto_pk_write_public_key_to_string(router->link_pkey,
 406                                           &link_pkey,&link_pkeylen)<0) {
 407     log_fn(LOG_WARN,"write link_pkey to string failed!");
 408     return -1;
 409   }
 410   strftime(published, 32, "%Y-%m-%d %H:%M:%S", gmtime(&router->published_on));
 411
 412   result = snprintf(s, maxlen,
 413                     "router %s %s %d %d %d %d\n"
 414                     "platform %s\n"
 415                     "published %s\n"
 416                     "onion-key\n%s"
 417                     "link-key\n%s"
 418                     "signing-key\n%s",
 419     router->nickname,
 420     router->address,
 421     router->or_port,
 422     router->socks_port,
 423     router->dir_port,
 424     router->bandwidth,
 425     platform,
 426     published,
 427     onion_pkey, link_pkey, identity_pkey);
 428
 429   free(onion_pkey);
 430   free(link_pkey);
 431   free(identity_pkey);
 432
 433   if(result < 0 || result >= maxlen) {
 434     /* apparently different glibcs do different things on snprintf error.. so check both */
 435     return -1;
 436   }
 437   written = result;
 438
 439   for(tmpe=router->exit_policy; tmpe; tmpe=tmpe->next) {
 440     in.s_addr = htonl(tmpe->addr);
 441     result = snprintf(s+written, maxlen-written, "%s %s",
 442         tmpe->policy_type == EXIT_POLICY_ACCEPT ? "accept" : "reject",
 443         tmpe->msk == 0 ? "*" : inet_ntoa(in));
 444     if(result < 0 || result+written > maxlen) {
 445       /* apparently different glibcs do different things on snprintf error.. so check both */
 446       return -1;
 447     }
 448     written += result;
 449     if (tmpe->msk != 0xFFFFFFFFu && tmpe->msk != 0) {
 450       in.s_addr = htonl(tmpe->msk);
 451       result = snprintf(s+written, maxlen-written, "/%s", inet_ntoa(in));
 452       if (result<0 || result+written > maxlen)
 453         return -1;
 454       written += result;
 455     }
 456     if (tmpe->prt) {
 457       result = snprintf(s+written, maxlen-written, ":%d\n", tmpe->prt);
 458       if (result<0 || result+written > maxlen)
 459         return -1;
 460       written += result;
 461     } else {
 462       if (written > maxlen-4)
 463         return -1;
 464       strcat(s+written, ":*\n");
 465       written += 3;
 466     }
 467   } /* end for */
 468   if (written > maxlen-256) /* Not enough room for signature. */
 469     return -1;
 470
 471   strcat(s+written, "router-signature\n");
 472   written += strlen(s+written);
 473   s[written] = '\0';
 474   if (router_get_router_hash(s, digest) < 0)
 475     return -1;
 476
 477   if (crypto_pk_private_sign(ident_key, digest, 20, signature) < 0) {
 478     log_fn(LOG_WARN, "Error signing digest");
 479     return -1;
 480   }
 481   strcat(s+written, "-----BEGIN SIGNATURE-----\n");
 482   written += strlen(s+written);
 483   if (base64_encode(s+written, maxlen-written, signature, 128) < 0) {
 484     log_fn(LOG_WARN, "Couldn't base64-encode signature");
 485     return -1;
 486   }
 487   written += strlen(s+written);
 488   strcat(s+written, "-----END SIGNATURE-----\n");
 489   written += strlen(s+written);
 490
 491   if (written > maxlen-2)
 492     return -1;
 493   /* include a last '\n' */
 494   s[written] = '\n';
 495   s[written+1] = 0;
 496
 497 #ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
 498   cp = s_tmp = s_dup = tor_strdup(s);
 499   ri_tmp = router_get_entry_from_string(&cp);
 500   if (!ri_tmp) {
 501     log_fn(LOG_ERR, "We just generated a router descriptor we can't parse: <<%s>>",
 502            s);
 503     return -1;
 504   }
 505   free(s_dup);
 506   routerinfo_free(ri_tmp);
 507 #endif
 508
 509   return written+1;
 510 }
 511
 512 /*
 513   Local Variables:
 514   mode:c
 515   indent-tabs-mode:nil
 516   c-basic-offset:2
 517   End:
 518 */