src/net_socket.c

   1 /*
   2     net_socket.c -- Handle various kinds of sockets.
   3     Copyright (C) 1998-2003 Ivo Timmermans <ivo@o2w.nl>,
   4                   2000-2003 Guus Sliepen <guus@sliepen.eu.org>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20     $Id: net_socket.c,v 1.1.2.30 2003/07/22 20:55:20 guus Exp $
  21 */
  22
  23 #include "system.h"
  24
  25 #include "avl_tree.h"
  26 #include "conf.h"
  27 #include "connection.h"
  28 #include "event.h"
  29 #include "logger.h"
  30 #include "meta.h"
  31 #include "net.h"
  32 #include "netutl.h"
  33 #include "protocol.h"
  34 #include "utils.h"
  35 #include "xalloc.h"
  36
  37 int addressfamily = AF_UNSPEC;
  38 int maxtimeout = 900;
  39 int seconds_till_retry = 5;
  40
  41 listen_socket_t listen_socket[MAXSOCKETS];
  42 int listen_sockets;
  43
  44 /* Setup sockets */
  45
  46 int setup_listen_socket(sockaddr_t *sa)
  47 {
  48         int nfd, flags;
  49         char *addrstr;
  50         int option;
  51         char *iface;
  52         struct ifreq ifr;
  53
  54         cp();
  55
  56         nfd = socket(sa->sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
  57
  58         if(nfd < 0) {
  59                 logger(LOG_ERR, _("Creating metasocket failed: %s"), strerror(errno));
  60                 return -1;
  61         }
  62
  63         flags = fcntl(nfd, F_GETFL);
  64
  65         if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
  66                 close(nfd);
  67                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
  68                            strerror(errno));
  69                 return -1;
  70         }
  71
  72         /* Optimize TCP settings */
  73
  74         option = 1;
  75         setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
  76
  77 #if defined(SOL_TCP) && defined(TCP_NODELAY)
  78         setsockopt(nfd, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
  79 #endif
  80
  81 #if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
  82         option = IPTOS_LOWDELAY;
  83         setsockopt(nfd, SOL_IP, IP_TOS, &option, sizeof(option));
  84 #endif
  85
  86         if(get_config_string
  87            (lookup_config(config_tree, "BindToInterface"), &iface)) {
  88 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
  89                 memset(&ifr, 0, sizeof(ifr));
  90                 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
  91
  92                 if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
  93                         close(nfd);
  94                         logger(LOG_ERR, _("Can't bind to interface %s: %s"), iface,
  95                                    strerror(errno));
  96                         return -1;
  97                 }
  98 #else
  99                 logger(LOG_WARNING, _("BindToInterface not supported on this platform"));
 100 #endif
 101         }
 102
 103         if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
 104                 close(nfd);
 105                 addrstr = sockaddr2hostname(sa);
 106                 logger(LOG_ERR, _("Can't bind to %s/tcp: %s"), addrstr,
 107                            strerror(errno));
 108                 free(addrstr);
 109                 return -1;
 110         }
 111
 112         if(listen(nfd, 3)) {
 113                 close(nfd);
 114                 logger(LOG_ERR, _("System call `%s' failed: %s"), "listen",
 115                            strerror(errno));
 116                 return -1;
 117         }
 118
 119         return nfd;
 120 }
 121
 122 int setup_vpn_in_socket(sockaddr_t *sa)
 123 {
 124         int nfd, flags;
 125         char *addrstr;
 126         int option;
 127 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
 128         char *iface;
 129         struct ifreq ifr;
 130 #endif
 131
 132         cp();
 133
 134         nfd = socket(sa->sa.sa_family, SOCK_DGRAM, IPPROTO_UDP);
 135
 136         if(nfd < 0) {
 137                 logger(LOG_ERR, _("Creating UDP socket failed: %s"), strerror(errno));
 138                 return -1;
 139         }
 140
 141         flags = fcntl(nfd, F_GETFL);
 142         if(fcntl(nfd, F_SETFL, flags | O_NONBLOCK) < 0) {
 143                 close(nfd);
 144                 logger(LOG_ERR, _("System call `%s' failed: %s"), "fcntl",
 145                            strerror(errno));
 146                 return -1;
 147         }
 148
 149         option = 1;
 150         setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(option));
 151
 152 #if defined(SOL_SOCKET) && defined(SO_BINDTODEVICE)
 153         if(get_config_string
 154            (lookup_config(config_tree, "BindToInterface"), &iface)) {
 155                 memset(&ifr, 0, sizeof(ifr));
 156                 strncpy(ifr.ifr_ifrn.ifrn_name, iface, IFNAMSIZ);
 157
 158                 if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr))) {
 159                         close(nfd);
 160                         logger(LOG_ERR, _("Can't bind to interface %s: %s"), iface,
 161                                    strerror(errno));
 162                         return -1;
 163                 }
 164         }
 165 #endif
 166
 167         if(bind(nfd, &sa->sa, SALEN(sa->sa))) {
 168                 close(nfd);
 169                 addrstr = sockaddr2hostname(sa);
 170                 logger(LOG_ERR, _("Can't bind to %s/udp: %s"), addrstr,
 171                            strerror(errno));
 172                 free(addrstr);
 173                 return -1;
 174         }
 175
 176         return nfd;
 177 }
 178
 179 void retry_outgoing(outgoing_t *outgoing)
 180 {
 181         event_t *event;
 182
 183         cp();
 184
 185         outgoing->timeout += 5;
 186
 187         if(outgoing->timeout > maxtimeout)
 188                 outgoing->timeout = maxtimeout;
 189
 190         event = new_event();
 191         event->handler = (event_handler_t) setup_outgoing_connection;
 192         event->time = now + outgoing->timeout;
 193         event->data = outgoing;
 194         event_add(event);
 195
 196         ifdebug(CONNECTIONS) logger(LOG_NOTICE,
 197                            _("Trying to re-establish outgoing connection in %d seconds"),
 198                            outgoing->timeout);
 199 }
 200
 201 void finish_connecting(connection_t *c)
 202 {
 203         cp();
 204
 205         ifdebug(CONNECTIONS) logger(LOG_INFO, _("Connected to %s (%s)"), c->name, c->hostname);
 206
 207         c->last_ping_time = now;
 208
 209         send_id(c);
 210 }
 211
 212 void do_outgoing_connection(connection_t *c)
 213 {
 214         char *address, *port;
 215         int option, result, flags;
 216
 217         cp();
 218
 219 begin:
 220         if(!c->outgoing->ai) {
 221                 if(!c->outgoing->cfg) {
 222                         ifdebug(CONNECTIONS) logger(LOG_ERR, _("Could not set up a meta connection to %s"),
 223                                            c->name);
 224                         c->status.remove = true;
 225                         retry_outgoing(c->outgoing);
 226                         return;
 227                 }
 228
 229                 get_config_string(c->outgoing->cfg, &address);
 230
 231                 if(!get_config_string(lookup_config(c->config_tree, "Port"), &port))
 232                         asprintf(&port, "655");
 233
 234                 c->outgoing->ai = str2addrinfo(address, port, SOCK_STREAM);
 235                 free(address);
 236                 free(port);
 237
 238                 c->outgoing->aip = c->outgoing->ai;
 239                 c->outgoing->cfg = lookup_config_next(c->config_tree, c->outgoing->cfg);
 240         }
 241
 242         if(!c->outgoing->aip) {
 243                 freeaddrinfo(c->outgoing->ai);
 244                 c->outgoing->ai = NULL;
 245                 goto begin;
 246         }
 247
 248         memcpy(&c->address, c->outgoing->aip->ai_addr,
 249                    c->outgoing->aip->ai_addrlen);
 250         c->outgoing->aip = c->outgoing->aip->ai_next;
 251
 252         if(c->hostname)
 253                 free(c->hostname);
 254
 255         c->hostname = sockaddr2hostname(&c->address);
 256
 257         ifdebug(CONNECTIONS) logger(LOG_INFO, _("Trying to connect to %s (%s)"), c->name,
 258                            c->hostname);
 259
 260         c->socket = socket(c->address.sa.sa_family, SOCK_STREAM, IPPROTO_TCP);
 261
 262         if(c->socket == -1) {
 263                 ifdebug(CONNECTIONS) logger(LOG_ERR, _("Creating socket for %s failed: %s"), c->hostname,
 264                                    strerror(errno));
 265
 266                 goto begin;
 267         }
 268
 269         /* Optimize TCP settings */
 270
 271 #if defined(SOL_TCP) && defined(TCP_NODELAY)
 272         option = 1;
 273         setsockopt(c->socket, SOL_TCP, TCP_NODELAY, &option, sizeof(option));
 274 #endif
 275
 276 #if defined(SOL_IP) && defined(IP_TOS)
 277         option = IPTOS_LOWDELAY;
 278         setsockopt(c->socket, SOL_IP, IP_TOS, &option, sizeof(option));
 279 #endif
 280
 281         /* Non-blocking */
 282
 283         flags = fcntl(c->socket, F_GETFL);
 284
 285         if(fcntl(c->socket, F_SETFL, flags | O_NONBLOCK) < 0) {
 286                 logger(LOG_ERR, _("fcntl for %s: %s"), c->hostname, strerror(errno));
 287         }
 288
 289         /* Connect */
 290
 291         result = connect(c->socket, &c->address.sa, SALEN(c->address.sa));
 292
 293         if(result == -1) {
 294                 if(errno == EINPROGRESS) {
 295                         c->status.connecting = true;
 296                         return;
 297                 }
 298
 299                 close(c->socket);
 300
 301                 ifdebug(CONNECTIONS) logger(LOG_ERR, _("%s: %s"), c->hostname, strerror(errno));
 302
 303                 goto begin;
 304         }
 305
 306         finish_connecting(c);
 307
 308         return;
 309 }
 310
 311 void setup_outgoing_connection(outgoing_t *outgoing)
 312 {
 313         connection_t *c;
 314         node_t *n;
 315
 316         cp();
 317
 318         n = lookup_node(outgoing->name);
 319
 320         if(n)
 321                 if(n->connection) {
 322                         ifdebug(CONNECTIONS) logger(LOG_INFO, _("Already connected to %s"), outgoing->name);
 323
 324                         n->connection->outgoing = outgoing;
 325                         return;
 326                 }
 327
 328         c = new_connection();
 329         c->name = xstrdup(outgoing->name);
 330         c->outcipher = myself->connection->outcipher;
 331         c->outdigest = myself->connection->outdigest;
 332         c->outmaclength = myself->connection->outmaclength;
 333         c->outcompression = myself->connection->outcompression;
 334
 335         init_configuration(&c->config_tree);
 336         read_connection_config(c);
 337
 338         outgoing->cfg = lookup_config(c->config_tree, "Address");
 339
 340         if(!outgoing->cfg) {
 341                 logger(LOG_ERR, _("No address specified for %s"), c->name);
 342                 free_connection(c);
 343                 free(outgoing->name);
 344                 free(outgoing);
 345                 return;
 346         }
 347
 348         c->outgoing = outgoing;
 349         c->last_ping_time = now;
 350
 351         connection_add(c);
 352
 353         do_outgoing_connection(c);
 354 }
 355
 356 /*
 357   accept a new tcp connect and create a
 358   new connection
 359 */
 360 bool handle_new_meta_connection(int sock)
 361 {
 362         connection_t *c;
 363         sockaddr_t sa;
 364         int fd, len = sizeof(sa);
 365
 366         cp();
 367
 368         fd = accept(sock, &sa.sa, &len);
 369
 370         if(fd < 0) {
 371                 logger(LOG_ERR, _("Accepting a new connection failed: %s"),
 372                            strerror(errno));
 373                 return false;
 374         }
 375
 376         sockaddrunmap(&sa);
 377
 378         c = new_connection();
 379         c->outcipher = myself->connection->outcipher;
 380         c->outdigest = myself->connection->outdigest;
 381         c->outmaclength = myself->connection->outmaclength;
 382         c->outcompression = myself->connection->outcompression;
 383
 384         c->address = sa;
 385         c->hostname = sockaddr2hostname(&sa);
 386         c->socket = fd;
 387         c->last_ping_time = now;
 388
 389         ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection from %s"), c->hostname);
 390
 391         connection_add(c);
 392
 393         c->allow_request = ID;
 394         send_id(c);
 395
 396         return true;
 397 }
 398
 399 void try_outgoing_connections(void)
 400 {
 401         static config_t *cfg = NULL;
 402         char *name;
 403         outgoing_t *outgoing;
 404
 405         cp();
 406
 407         for(cfg = lookup_config(config_tree, "ConnectTo"); cfg;
 408                 cfg = lookup_config_next(config_tree, cfg)) {
 409                 get_config_string(cfg, &name);
 410
 411                 if(!check_id(name)) {
 412                         logger(LOG_ERR,
 413                                    _("Invalid name for outgoing connection in %s line %d"),
 414                                    cfg->file, cfg->line);
 415                         free(name);
 416                         continue;
 417                 }
 418
 419                 outgoing = xmalloc_and_zero(sizeof(*outgoing));
 420                 outgoing->name = name;
 421                 setup_outgoing_connection(outgoing);
 422         }
 423 }