src/network.c

   1 /* $Id$
   2  * UDP Gateway utility network layer
   3  * Copyright (C) 2004 Jan Kratochvil <project-udpgate@jankratochvil.net>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; exactly version 2 of June 1991 is required
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  */
  18
  19
  20 #include "config.h"
  21
  22 #include <glib/gmessages.h>
  23 #include <glib/gmain.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26 #include <glib/glist.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <sys/types.h>
  30 #include <signal.h>
  31 #include <errno.h>
  32 #include <glib/giochannel.h>
  33 #include <sys/ioctl.h>
  34 #include <string.h>
  35 #include <glib/galloca.h>
  36 #include <glib/gprintf.h>
  37 #include <glib/grand.h>
  38
  39 #include "network.h"
  40 #include "packet.h"
  41 #include "main.h"       /* for optarg_verbose */
  42
  43
  44 /* Config: */
  45 #define NETWORK_PATHNAME_PID "/var/run/udpgate.pid"
  46 #define SOCK_SOURCE_CHECK_EVENTS (G_IO_IN)      /* |G_IO_PRI */
  47 #define SOCK_SOURCE_CHECK_REVENTS (SOCK_SOURCE_CHECK_EVENTS)    /* |G_IO_ERR|G_IO_HUP|G_IO_NVAL */
  48 #define SERVER_INADDR 0x511F02EA        /* paulina.vellum.cz = 81.31.2.234; host order */
  49 #define SERVER_PORT   9201      /* host order */
  50 #define PROBE_INADDR  SERVER_INADDR     /* host order */
  51 #define PROBE_PORT    8201      /* host order */
  52 #define CLIENT_TIMEOUT_SEC (5*60)
  53 #define PROBE_TIMEOUT_SEC_BASE 5
  54 #define PROBE_TIMEOUT_SEC_MAX 3500
  55
  56
  57 void (*network_notify_hostip)(guint32 hostip_guint32);
  58
  59
  60 struct client {
  61         GPollFD gpollfd;
  62         struct sockaddr_in sockaddr_in_from;
  63         guint timeout_id;
  64         };
  65
  66 static GSource *sock_gsource;
  67
  68 static GList *sock_client_list; /* of 'struct client *', incl. 'master' and 'probe' */
  69 static struct client *master;   /* no 'timeout' permitted */
  70 static struct client *probe;    /* 'timeout' permitted */
  71 static guint32 probe_unique;
  72 static guint probe_timeout_sec_now;
  73 guint probe_timeout_sec_max=G_MAXUINT;
  74 static gint port_local; /* for 'probe' resends */
  75
  76 static gboolean write_daemon_running(pid_t pid);
  77
  78 pid_t is_daemon_running(void)
  79 {
  80 FILE *f;
  81 char buf[LINE_MAX],*got;
  82 int pid_int;
  83
  84         if (sock_gsource)
  85                 return getpid();
  86
  87         if (!(f=fopen(NETWORK_PATHNAME_PID,"r")))
  88                 goto err;
  89         got=fgets(buf,sizeof(buf),f);
  90         fclose(f);      /* FIXME: error ignored */
  91         if (got!=buf) {
  92 err_unlink:
  93                 write_daemon_running((pid_t)-1);        /* unlink */
  94 err:
  95                 return (pid_t)-1;
  96                 }
  97         pid_int=atoi(buf);
  98         if (pid_int<=1)
  99                 goto err_unlink;
 100         if (kill((pid_t)pid_int,0)) {
 101                 if (errno==ESRCH)
 102                         goto err_unlink;
 103                 goto err;
 104                 }
 105         return (pid_t)pid_int;
 106 }
 107
 108 static gboolean write_daemon_running(pid_t pid)
 109 {
 110 FILE *f;
 111
 112         if (pid==(pid_t)-1) {
 113                 if (unlink(NETWORK_PATHNAME_PID)) {
 114                         if (errno!=ENOENT)
 115                                 g_warning(_("Error removing PID file \"%s\": %m"),NETWORK_PATHNAME_PID);
 116                         return FALSE;
 117                         }
 118                 return TRUE;
 119                 }
 120         if (!(f=fopen(NETWORK_PATHNAME_PID,"w"))) {
 121                 g_warning(_("Error writing PID %d to \"%s\": %m"),(int)pid,NETWORK_PATHNAME_PID);
 122                 return FALSE;
 123                 }
 124         fprintf(f,"%d\n",(int)pid);     /* errors ignored */
 125         fclose(f);      /* FIXME: error ignored */
 126         return TRUE;
 127 }
 128
 129 static void client_timeout_remove(struct client *client)
 130 {
 131         g_return_if_fail(client!=NULL);
 132         g_return_if_fail(client!=master);
 133
 134         if (client->timeout_id) {
 135 gboolean errgboolean;
 136
 137                 if (optarg_verbose)
 138                         g_message(_("Client fd %d removed timeout id %d"),client->gpollfd.fd,client->timeout_id);
 139                 errgboolean=g_source_remove(client->timeout_id);
 140                 g_assert(errgboolean==TRUE);
 141                 client->timeout_id=0;
 142                 }
 143 }
 144
 145 static gboolean client_touch_timeout(struct client *client);
 146
 147 static void client_touch(struct client *client,guint timeout_sec)
 148 {
 149         g_return_if_fail(client!=NULL);
 150         g_return_if_fail(client!=master);
 151         g_return_if_fail(timeout_sec>0);
 152
 153         client_timeout_remove(client);
 154         client->timeout_id=g_timeout_add(
 155                         timeout_sec*1000,       /* interval; msec */
 156                         (GSourceFunc)client_touch_timeout,      /* function */
 157                         client);        /* data */
 158         if (optarg_verbose)
 159                 g_message(_("Client fd %d new timeout id %d"),client->gpollfd.fd,client->timeout_id);
 160         g_assert(client->timeout_id!=0);
 161 }
 162
 163 static void client_destroy(struct client *client);
 164 static gboolean probe_send(struct client *probe,gint port_local);
 165
 166 static gboolean client_touch_timeout(struct client *client)
 167 {
 168         g_return_val_if_fail(client!=NULL,FALSE);       /* FALSE=>should be removed */
 169         g_return_val_if_fail(client!=master,FALSE);     /* FALSE=>should be removed */
 170
 171         if (optarg_verbose)
 172                 g_message(_("Client fd %d timeout id %d occured/entered"),client->gpollfd.fd,client->timeout_id);
 173
 174         /* Do not destroy the timeout in client_destroy().
 175          * It would crash GLib - we remove it be returning FALSE from here.
 176          */
 177         g_assert(client->timeout_id!=0);
 178         client->timeout_id=0;
 179
 180         if (client==probe) {
 181                 if (probe_timeout_sec_now<probe_timeout_sec_max) {
 182                         probe_timeout_sec_now*=PROBE_TIMEOUT_SEC_BASE;
 183                         g_assert(probe_timeout_sec_max==G_MAXUINT || probe_timeout_sec_max<PROBE_TIMEOUT_SEC_MAX);
 184                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,probe_timeout_sec_max);
 185                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,PROBE_TIMEOUT_SEC_MAX);
 186                         if (probe_send(probe,port_local)) {
 187                                 client_touch(probe,probe_timeout_sec_now);      /* timeout */
 188                                 return FALSE;   /* GSource should be removed */
 189                                 }
 190                         /* failure FALLTHRU */
 191                         }
 192                 network_stop();
 193                 /* Never destroy 'client' now - it has been destroyed by network_stop()! */
 194                 g_warning(_("No probe response from the server, stopping the daemon. Please check your public Internet connectivity."));
 195                 }
 196         else {
 197                 client_destroy(client);
 198                 }
 199
 200         if (optarg_verbose)
 201                 g_message(_("Client timeout occurance finish"));
 202
 203         return FALSE;   /* GSource should be removed */
 204 }
 205
 206 static void handle_master_probe(const void *packet,size_t gotlen,const struct sockaddr_in *sockaddr_in_from)
 207 {
 208 GHashTable *got_hash;
 209 gpointer got_unique_gpointer;
 210 gpointer hostip_gpointer;
 211 guint32 hostip_guint32;
 212
 213         g_return_if_fail(packet!=NULL);
 214         g_return_if_fail(sockaddr_in_from!=NULL);
 215
 216         if (!probe)
 217                 return;
 218
 219         if (!(got_hash=packet_disassembly(packet,gotlen)))
 220                 return;
 221         if (!(g_hash_table_lookup_extended(
 222                         got_hash,       /* hash_table */
 223                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),        /* lookup_key */
 224                         NULL,   /* orig_key */
 225                         &got_unique_gpointer))) {
 226 err_packet_disassembly_destroy_got_hash:
 227                 packet_disassembly_destroy(got_hash);
 228                 return;
 229                 }
 230         if (GPOINTER_TO_UINT(got_unique_gpointer)!=probe_unique)
 231                 goto err_packet_disassembly_destroy_got_hash;
 232         if (!(g_hash_table_lookup_extended(
 233                         got_hash,       /* hash_table */
 234                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_INADDR),       /* lookup_key */
 235                         NULL,   /* orig_key */
 236                         &hostip_gpointer)))
 237                 goto err_packet_disassembly_destroy_got_hash;
 238         hostip_guint32=GPOINTER_TO_UINT(hostip_gpointer);
 239         packet_disassembly_destroy(got_hash);
 240
 241         client_destroy(probe);
 242         if (network_notify_hostip)
 243                 (*network_notify_hostip)(hostip_guint32);
 244 }
 245
 246 static struct client *client_new(void);
 247
 248 static void handle_master(struct client *master)
 249 {
 250         g_return_if_fail(master!=NULL);
 251
 252         for (;;) {
 253 char packet[0x10000];
 254 ssize_t gotlen;
 255 struct sockaddr_in sockaddr_in_from;
 256 struct client *client=NULL      /* Prevent false positive: might be used uninitialized */;
 257 struct sockaddr_in sockaddr_in_server;
 258 socklen_t sockaddr_in_from_length;
 259 GList *clientl;
 260
 261                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 262                 if (-1==(gotlen=recvfrom(
 263                                 master->gpollfd.fd,     /* s */
 264                                 packet, /* buf */
 265                                 sizeof(packet), /* len */
 266                                 0,      /* flags */
 267                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 268                                 &sockaddr_in_from_length)))     /* fromlen */
 269                         break;
 270
 271                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 272                         continue;
 273
 274                 if (packet_recognized(packet,gotlen)) {
 275                         handle_master_probe(packet,gotlen,&sockaddr_in_from);
 276                         continue;
 277                         }
 278                 /* Not yet initialized by 'probe' reply - drop it. */
 279                 if (probe)
 280                         continue;
 281
 282                 /* FIXME: Performance: Ugly search... */
 283                 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 284                         client=clientl->data;
 285                         if (client==master)
 286                                 continue;
 287                         if (1
 288                                         && client->sockaddr_in_from.sin_family     ==sockaddr_in_from.sin_family
 289                                         && client->sockaddr_in_from.sin_port       ==sockaddr_in_from.sin_port
 290                                         && client->sockaddr_in_from.sin_addr.s_addr==sockaddr_in_from.sin_addr.s_addr)
 291                                 break;
 292                         }
 293                 if (!clientl) {
 294                         client=client_new();
 295                         client->sockaddr_in_from=sockaddr_in_from;
 296                         }
 297                 client_touch(client,CLIENT_TIMEOUT_SEC);
 298                 UDPGATE_MEMZERO(&sockaddr_in_server);
 299                 sockaddr_in_server.sin_family=AF_INET;
 300                 sockaddr_in_server.sin_port=htons(SERVER_PORT);
 301                 sockaddr_in_server.sin_addr.s_addr=htonl(SERVER_INADDR);
 302                 /* FIXME: errors checking */
 303                 sendto(
 304                                 client->gpollfd.fd,     /* s */
 305                                 packet, /* msg */
 306                                 gotlen, /* len */
 307                                 0,      /* flags */
 308                                 (struct sockaddr *)&sockaddr_in_server, /* to */
 309                                 sizeof(sockaddr_in_server));    /* tolen */
 310                 }
 311 }
 312
 313 static void handle_probe(struct client *probe)
 314 {
 315         g_return_if_fail(probe!=NULL);
 316
 317         for (;;) {
 318 ssize_t gotlen;
 319 struct sockaddr_in sockaddr_in_from;
 320 char packet[0x10000];
 321 socklen_t sockaddr_in_from_length;
 322
 323                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 324                 if (-1==(gotlen=recvfrom(
 325                                 master->gpollfd.fd,     /* s */
 326                                 packet, /* buf */
 327                                 sizeof(packet), /* len */
 328                                 0,      /* flags */
 329                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 330                                 &sockaddr_in_from_length)))     /* fromlen */
 331                         break;
 332                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 333                         continue;
 334
 335                 /* Probe socket should have no response; maybe some ICMP errors - ignored. */
 336                 }
 337 }
 338
 339 static void handle_client(struct client *client)
 340 {
 341         g_return_if_fail(client!=NULL);
 342         g_return_if_fail(master!=NULL);
 343
 344         for (;;) {
 345 ssize_t gotlen;
 346 struct sockaddr_in sockaddr_in_from;
 347 char packet [0x10000];
 348 socklen_t sockaddr_in_from_length;
 349
 350                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 351                 if (-1==(gotlen=recvfrom(
 352                                 client->gpollfd.fd,     /* s */
 353                                 packet, /* buf */
 354                                 sizeof(packet), /* len */
 355                                 0,      /* flags */
 356                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 357                                 &sockaddr_in_from_length)))     /* fromlen */
 358                         break;
 359                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 360                         continue;
 361                 client_touch(client,CLIENT_TIMEOUT_SEC);
 362                 /* FIXME: errors checking */
 363                 sendto(
 364                                 master->gpollfd.fd,     /* s */
 365                                 packet, /* msg */
 366                                 gotlen, /* len */
 367                                 0,      /* flags */
 368                                 (struct sockaddr *)&client->sockaddr_in_from,   /* to */
 369                                 sizeof(client->sockaddr_in_from));      /* tolen */
 370                 }
 371 }
 372
 373 static gboolean sock_source_callback(gpointer data /* unused */)
 374 {
 375 GList *clientl;
 376
 377         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 378 struct client *client=clientl->data;
 379
 380                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS) {
 381                         /**/ if (client==master)
 382                                 handle_master(client);
 383                         else if (client==probe)
 384                                 handle_probe(client);
 385                         else
 386                                 handle_client(client);
 387                         }
 388                 }
 389
 390         return TRUE; /* the source should be kept active */
 391 }
 392
 393 static gboolean sock_source_prepare(GSource *source,gint *timeout)
 394 {
 395         *timeout=-1;
 396
 397         return FALSE;
 398 }
 399
 400 static gboolean sock_source_check(GSource *source)
 401 {
 402 GList *clientl;
 403
 404         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 405 struct client *client=clientl->data;
 406
 407                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS)
 408                         return TRUE;
 409                 }
 410         return FALSE;
 411 }
 412
 413 static gboolean sock_source_dispatch(GSource *source,GSourceFunc callback,gpointer user_data)
 414 {
 415         g_assert(callback!=NULL);
 416         return (*callback)(user_data);
 417 }
 418
 419 static GSourceFuncs sock_source_watch_funcs={
 420                 sock_source_prepare,
 421                 sock_source_check,
 422                 sock_source_dispatch,
 423                 NULL, /* finalize */
 424                 };
 425
 426 static void sock_gsource_destroy(void)
 427 {
 428         while (sock_client_list)
 429                 client_destroy(sock_client_list->data);
 430
 431         g_assert(master==NULL);
 432         g_assert(probe==NULL);
 433
 434         if (sock_gsource) {
 435                 g_source_destroy(sock_gsource);
 436                 sock_gsource=NULL;
 437                 }
 438
 439         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 440 }
 441
 442 static gboolean sock_gsource_new(void)
 443 {
 444         if (sock_gsource)
 445                 return TRUE;
 446
 447         g_assert(sock_client_list==NULL);
 448
 449         /* attach sock_source_callback() to watch for any abnormalities
 450          * on our open pipe 'parentheart_fds' and terminate the child if parent dies.
 451          */
 452         if (!(sock_gsource=g_source_new(&sock_source_watch_funcs,sizeof(GSource)))) {
 453                 g_warning("g_source_new(): %m");
 454                 return FALSE;
 455                 }
 456         g_source_set_callback(
 457                         sock_gsource,  /* source */
 458                         sock_source_callback,  /* func */
 459                         NULL, /* data */
 460                         NULL);  /* notify */
 461         if (!g_source_attach(   /* returns 'guint' id */
 462                         sock_gsource,  /* source */
 463                         NULL)) {        /* context; NULL means 'default context' */
 464                 g_warning("g_source_attach(gsource,NULL): %m");
 465                 sock_gsource_destroy();
 466                 return FALSE;
 467                 }
 468         return TRUE;
 469 }
 470
 471 static struct client *client_new(void)
 472 {
 473 struct client *client;
 474 static unsigned long oneul=1;
 475 int sock;
 476
 477         if (!sock_gsource_new())
 478                 return FALSE;
 479
 480         if (-1==(sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP))) {
 481                 g_warning("socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP): %m");
 482                 return NULL;
 483                 }
 484         if (ioctl(sock,FIONBIO,&oneul)) {       /* non-blocking mode */
 485                 g_warning("ioctl(sock,FIONBIO,&1): %m");
 486                 close(sock);    /* errors ignored */
 487                 return NULL;
 488                 }
 489
 490         udpgate_new(client);
 491         client->gpollfd.fd=sock;
 492         client->gpollfd.events=SOCK_SOURCE_CHECK_EVENTS;
 493         client->gpollfd.revents=0;
 494         client->timeout_id=0;
 495         sock_client_list=g_list_prepend(sock_client_list,client);
 496         g_source_add_poll(sock_gsource,&client->gpollfd);
 497
 498         if (optarg_verbose)
 499                 g_message(_("Client fd %d created"),client->gpollfd.fd);
 500
 501         return client;
 502 }
 503
 504 static void client_destroy(struct client *client)
 505 {
 506         g_return_if_fail(client!=NULL);
 507
 508         if (!sock_gsource_new())
 509                 return;
 510
 511         if (optarg_verbose)
 512                 g_message(_("Client fd %d timeout id %d destroy enter"),client->gpollfd.fd,client->timeout_id);
 513
 514         if (client==master) {
 515                 master=NULL;
 516                 g_assert(client->timeout_id==0);
 517                 }
 518         else {
 519                 if (client==probe)
 520                         probe=NULL;
 521                 client_timeout_remove(client);
 522                 }
 523
 524         g_source_remove_poll(sock_gsource,&client->gpollfd);
 525         sock_client_list=g_list_remove(sock_client_list,client);
 526         close(client->gpollfd.fd);      /* errors ignored */
 527
 528         if (optarg_verbose)
 529                 g_message(_("Client fd %d timeout id %d destroy finish"),client->gpollfd.fd,client->timeout_id);
 530
 531         g_free(client);
 532 }
 533
 534 static gboolean probe_send(struct client *probe,gint port_local)
 535 {
 536 struct sockaddr_in sockaddr_in_server;
 537 GHashTable *probe_hash;
 538 gpointer packet;
 539 size_t packet_length;
 540
 541         g_return_val_if_fail(probe!=NULL,FALSE);
 542
 543         probe_unique=g_random_int();
 544
 545         probe_hash=g_hash_table_new(
 546                         g_direct_hash,  /* hash_func */
 547                         g_direct_equal);        /* key_equal_func */
 548         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_PORT) ,GUINT_TO_POINTER(port_local));
 549         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),GUINT_TO_POINTER(probe_unique));
 550         packet=packet_assembly(&packet_length,probe_hash);
 551         g_hash_table_destroy(probe_hash);
 552         if (!packet)
 553                 return FALSE;
 554
 555         UDPGATE_MEMZERO(&sockaddr_in_server);
 556         sockaddr_in_server.sin_family=AF_INET;
 557         sockaddr_in_server.sin_port=htons(PROBE_PORT);
 558         sockaddr_in_server.sin_addr.s_addr=htonl(PROBE_INADDR);
 559         /* FIXME: errors checking */
 560         sendto(
 561                         probe->gpollfd.fd,      /* s */
 562                         packet, /* msg */
 563                         packet_length,  /* len */
 564                         0,      /* flags */
 565                         (struct sockaddr *)&sockaddr_in_server, /* to */
 566                         sizeof(sockaddr_in_server));    /* tolen */
 567
 568         return TRUE;
 569 }
 570
 571 static gboolean master_start(gint port)
 572 {
 573 struct sockaddr_in sockaddr_in;
 574
 575         g_return_val_if_fail(port>=0,FALSE);
 576         g_return_val_if_fail(master==NULL,FALSE);
 577
 578         /* Setup 'master': */
 579         if (!(master=client_new()))
 580                 return FALSE;
 581         UDPGATE_MEMZERO(&sockaddr_in);
 582         sockaddr_in.sin_family=AF_INET;
 583         sockaddr_in.sin_port=htons(port);
 584         sockaddr_in.sin_addr.s_addr=htonl(INADDR_ANY);
 585         if (bind(master->gpollfd.fd,(struct sockaddr *)&sockaddr_in,sizeof(sockaddr_in))) {
 586                 g_warning("bind(sock,{AF_INET,INADDR_ANY:%d}): %m",(int)port);
 587                 return FALSE;
 588                 }
 589         return TRUE;
 590 }
 591
 592 static gboolean probe_start(gint port)
 593 {
 594         g_return_val_if_fail(port>=0,FALSE);
 595         g_return_val_if_fail(probe==NULL,FALSE);
 596
 597         /* Setup 'probe': */
 598         if (!(probe=client_new()))
 599                 return FALSE;
 600         port_local=port;
 601         if (!probe_send(probe,port)) {
 602                 client_destroy(probe);
 603                 return FALSE;
 604                 }
 605         probe_timeout_sec_now=PROBE_TIMEOUT_SEC_BASE;
 606         client_touch(probe,probe_timeout_sec_now);      /* timeout */
 607         return TRUE;
 608 }
 609
 610 gboolean network_start(gint port)
 611 {
 612 pid_t daemon_pid;
 613
 614         g_return_val_if_fail(port>=0,FALSE);
 615
 616         if ((pid_t)-1!=(daemon_pid=is_daemon_running())) {
 617                 g_warning(_("Cannot start network daemon: Daemon is already running on PID %d"),(int)daemon_pid);
 618                 return FALSE;
 619                 }
 620         if (!master_start(port)) {
 621                 sock_gsource_destroy();
 622                 return FALSE;
 623                 }
 624         if (!probe_start(port)) {
 625                 sock_gsource_destroy();
 626                 return FALSE;
 627                 }
 628         write_daemon_running(getpid()); /* errors ignored */
 629         if (network_notify_hostip)
 630                 (*network_notify_hostip)(0);
 631         return TRUE;
 632 }
 633
 634 gboolean optarg_port_set_string(const gchar *port_string)
 635 {
 636 char *endp;
 637 long port_long;
 638
 639         g_return_val_if_fail(port_string!=NULL,FALSE);
 640
 641         port_long=strtol(port_string,&endp,0);
 642         if (endp && *endp) {
 643                 g_warning(_("Invalid port specification, offending string: %s"),endp);
 644                 return FALSE;
 645                 }
 646         if (port_long<1 || port_long>=G_MAXINT || (endp && *endp)) {
 647                 g_warning(_("Invalid port integer number specification (%ld)"),port_long);
 648                 return FALSE;
 649                 }
 650         optarg_port=port_long;
 651         return TRUE;
 652 }
 653
 654 gboolean network_stop(void)
 655 {
 656 pid_t daemon_pid;
 657 int errno_save;
 658
 659         if ((pid_t)-1==(daemon_pid=is_daemon_running())) {
 660                 g_warning(_("Cannot stop network daemon: Daemon is not running"));
 661                 return FALSE;
 662                 }
 663         if (daemon_pid==getpid()) {
 664                 sock_gsource_destroy();
 665                 goto ok;
 666                 }
 667         errno=0;
 668         kill(daemon_pid,SIGKILL);
 669         errno_save=errno;
 670         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 671         if (errno_save)  {
 672                 g_warning(udpgate_printf_alloca(_("Unable to stop the daemon at PID %d: %s"),
 673                                 (int)daemon_pid,strerror(errno_save)));
 674                 return FALSE;
 675                 }
 676 ok:
 677         if (network_notify_hostip)
 678                 (*network_notify_hostip)(0);
 679         return TRUE;
 680 }
 681
 682 static GMainLoop *gmainloop;
 683 static void network_detach_network_notify_hostip(guint32 hostip_guint32)
 684 {
 685         if (!hostip_guint32)
 686                 g_main_loop_quit(gmainloop);
 687 }
 688
 689 gboolean network_detach(void)
 690 {
 691 pid_t daemon_pid,forked_pid;
 692
 693         if ((pid_t)-1==(daemon_pid=is_daemon_running()))
 694                 return TRUE;
 695         if (getpid()!=daemon_pid)
 696                 return TRUE;
 697         if (!optarg_no_fork) {
 698                 if ((pid_t)-1==(forked_pid=fork())) {
 699                         g_warning("fork(2): %m");
 700                         return FALSE;
 701                         }
 702                 if (forked_pid) {
 703                         /* parent */
 704                         return TRUE;
 705                         }
 706                 write_daemon_running(getpid()); /* errors ignored */
 707                 optarg_verbose=0;
 708                 close(STDIN_FILENO);
 709                 close(STDOUT_FILENO);
 710                 close(STDERR_FILENO);
 711                 setpgrp();
 712                 setsid();
 713                 }
 714
 715         network_notify_hostip=network_detach_network_notify_hostip;
 716         gmainloop=g_main_loop_new(
 717                         NULL,   /* context */
 718                         TRUE);  /* is_running; ignored */
 719         g_main_loop_run(gmainloop);     /* loop */
 720         /* Unable to contact the server, aborting. */
 721         return FALSE;
 722 }