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 0x7F000001
  49 #undef  SERVER_INADDR
  50 #define SERVER_INADDR 0x511F02EA        /* paulina.vellum.cz = 81.31.2.234; host order */
  51 #define SERVER_PORT   9201      /* host order */
  52 #define PROBE_INADDR  SERVER_INADDR     /* host order */
  53 #define PROBE_PORT    8202      /* host order */
  54 #define CLIENT_TIMEOUT_SEC (5*60)
  55 #define PROBE_TIMEOUT_SEC_BASE 5
  56 #define PROBE_TIMEOUT_SEC_MAX 3500
  57
  58
  59 void (*network_notify_hostip)(guint32 hostip_guint32);
  60
  61
  62 struct client {
  63         GPollFD gpollfd;
  64         struct sockaddr_in sockaddr_in_from;
  65         guint timeout_id;
  66         };
  67
  68 static GSource *sock_gsource;
  69
  70 static GList *sock_client_list; /* of 'struct client *', incl. 'master' and 'probe' */
  71 static struct client *master;   /* no 'timeout' permitted */
  72 static struct client *probe;    /* 'timeout' permitted */
  73 static guint32 probe_unique;
  74 static guint probe_timeout_sec_now;
  75 guint probe_timeout_sec_max=G_MAXUINT;
  76 static gint port_local; /* for 'probe' resends */
  77
  78 static gboolean write_daemon_running(pid_t pid);
  79
  80 pid_t is_daemon_running(void)
  81 {
  82 FILE *f;
  83 char buf[LINE_MAX],*got;
  84 int pid_int;
  85
  86         if (sock_gsource)
  87                 return getpid();
  88
  89         if (!(f=fopen(NETWORK_PATHNAME_PID,"r")))
  90                 goto err;
  91         got=fgets(buf,sizeof(buf),f);
  92         fclose(f);      /* FIXME: error ignored */
  93         if (got!=buf) {
  94 err_unlink:
  95                 write_daemon_running((pid_t)-1);        /* unlink */
  96 err:
  97                 return (pid_t)-1;
  98                 }
  99         pid_int=atoi(buf);
 100         if (pid_int<=1)
 101                 goto err_unlink;
 102         if (kill((pid_t)pid_int,0)) {
 103                 if (errno==ESRCH)
 104                         goto err_unlink;
 105                 goto err;
 106                 }
 107         return (pid_t)pid_int;
 108 }
 109
 110 static gboolean write_daemon_running(pid_t pid)
 111 {
 112 FILE *f;
 113
 114         if (pid==(pid_t)-1) {
 115                 if (unlink(NETWORK_PATHNAME_PID)) {
 116                         if (errno!=ENOENT)
 117                                 g_warning(_("Error removing PID file \"%s\": %m"),NETWORK_PATHNAME_PID);
 118                         return FALSE;
 119                         }
 120                 return TRUE;
 121                 }
 122         if (!(f=fopen(NETWORK_PATHNAME_PID,"w"))) {
 123                 g_warning(_("Error writing PID %d to \"%s\": %m"),(int)pid,NETWORK_PATHNAME_PID);
 124                 return FALSE;
 125                 }
 126         fprintf(f,"%d\n",(int)pid);     /* errors ignored */
 127         fclose(f);      /* FIXME: error ignored */
 128         return TRUE;
 129 }
 130
 131 static void client_timeout_remove(struct client *client)
 132 {
 133         g_return_if_fail(client!=NULL);
 134         g_return_if_fail(client!=master);
 135
 136         if (client->timeout_id) {
 137 gboolean errgboolean;
 138
 139                 if (optarg_verbose)
 140                         g_message(_("Client fd %d removed timeout id %d"),client->gpollfd.fd,client->timeout_id);
 141                 errgboolean=g_source_remove(client->timeout_id);
 142                 g_assert(errgboolean==TRUE);
 143                 client->timeout_id=0;
 144                 }
 145 }
 146
 147 static gboolean client_touch_timeout(struct client *client);
 148
 149 static void client_touch(struct client *client,guint timeout_sec)
 150 {
 151         g_return_if_fail(client!=NULL);
 152         g_return_if_fail(client!=master);
 153         g_return_if_fail(timeout_sec>0);
 154
 155         client_timeout_remove(client);
 156         client->timeout_id=g_timeout_add(
 157                         timeout_sec*1000,       /* interval; msec */
 158                         (GSourceFunc)client_touch_timeout,      /* function */
 159                         client);        /* data */
 160         if (optarg_verbose)
 161                 g_message(_("Client fd %d new timeout id %d"),client->gpollfd.fd,client->timeout_id);
 162         g_assert(client->timeout_id!=0);
 163 }
 164
 165 static void client_destroy(struct client *client);
 166 static gboolean probe_send(struct client *probe,gint port_local);
 167
 168 static gboolean client_touch_timeout(struct client *client)
 169 {
 170         g_return_val_if_fail(client!=NULL,FALSE);       /* FALSE=>should be removed */
 171         g_return_val_if_fail(client!=master,FALSE);     /* FALSE=>should be removed */
 172
 173         if (optarg_verbose)
 174                 g_message(_("Client fd %d timeout id %d occured/entered"),client->gpollfd.fd,client->timeout_id);
 175
 176         /* Do not destroy the timeout in client_destroy().
 177          * It would crash GLib - we remove it be returning FALSE from here.
 178          */
 179         g_assert(client->timeout_id!=0);
 180         client->timeout_id=0;
 181
 182         if (client==probe) {
 183                 if (probe_timeout_sec_now<probe_timeout_sec_max) {
 184                         probe_timeout_sec_now*=PROBE_TIMEOUT_SEC_BASE;
 185                         g_assert(probe_timeout_sec_max==G_MAXUINT || probe_timeout_sec_max<PROBE_TIMEOUT_SEC_MAX);
 186                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,probe_timeout_sec_max);
 187                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,PROBE_TIMEOUT_SEC_MAX);
 188                         if (probe_send(probe,port_local)) {
 189                                 client_touch(probe,probe_timeout_sec_now);      /* timeout */
 190                                 return FALSE;   /* GSource should be removed */
 191                                 }
 192                         /* failure FALLTHRU */
 193                         }
 194                 network_stop();
 195                 /* Never destroy 'client' now - it has been destroyed by network_stop()! */
 196                 g_warning(_("No probe response from the server, stopping the daemon. Please check your public Internet connectivity."));
 197                 }
 198         else {
 199                 client_destroy(client);
 200                 }
 201
 202         if (optarg_verbose)
 203                 g_message(_("Client timeout occurance finish"));
 204
 205         return FALSE;   /* GSource should be removed */
 206 }
 207
 208 static void handle_master_probe(const void *packet,size_t gotlen,const struct sockaddr_in *sockaddr_in_from)
 209 {
 210 GHashTable *got_hash;
 211 gpointer got_unique_gpointer;
 212 gpointer hostip_gpointer;
 213 guint32 hostip_guint32;
 214
 215         g_return_if_fail(packet!=NULL);
 216         g_return_if_fail(sockaddr_in_from!=NULL);
 217
 218         if (!probe)
 219                 return;
 220
 221         if (!(got_hash=packet_disassembly(packet,gotlen)))
 222                 return;
 223         if (!(g_hash_table_lookup_extended(
 224                         got_hash,       /* hash_table */
 225                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),        /* lookup_key */
 226                         NULL,   /* orig_key */
 227                         &got_unique_gpointer))) {
 228 err_packet_disassembly_destroy_got_hash:
 229                 packet_disassembly_destroy(got_hash);
 230                 return;
 231                 }
 232         if (GPOINTER_TO_UINT(got_unique_gpointer)!=probe_unique)
 233                 goto err_packet_disassembly_destroy_got_hash;
 234         if (!(g_hash_table_lookup_extended(
 235                         got_hash,       /* hash_table */
 236                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_INADDR),       /* lookup_key */
 237                         NULL,   /* orig_key */
 238                         &hostip_gpointer)))
 239                 goto err_packet_disassembly_destroy_got_hash;
 240         hostip_guint32=GPOINTER_TO_UINT(hostip_gpointer);
 241         packet_disassembly_destroy(got_hash);
 242
 243         client_destroy(probe);
 244         if (network_notify_hostip)
 245                 (*network_notify_hostip)(hostip_guint32);
 246 }
 247
 248 static struct client *client_new(void);
 249
 250 static void handle_master(struct client *master)
 251 {
 252         g_return_if_fail(master!=NULL);
 253
 254         for (;;) {
 255 char packet[0x10000];
 256 ssize_t gotlen;
 257 struct sockaddr_in sockaddr_in_from;
 258 struct client *client=NULL      /* Prevent false positive: might be used uninitialized */;
 259 struct sockaddr_in sockaddr_in_server;
 260 socklen_t sockaddr_in_from_length;
 261 GList *clientl;
 262
 263                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 264                 if (-1==(gotlen=recvfrom(
 265                                 master->gpollfd.fd,     /* s */
 266                                 packet, /* buf */
 267                                 sizeof(packet), /* len */
 268                                 0,      /* flags */
 269                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 270                                 &sockaddr_in_from_length)))     /* fromlen */
 271                         break;
 272
 273                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 274                         continue;
 275
 276                 if (packet_recognized(packet,gotlen)) {
 277                         handle_master_probe(packet,gotlen,&sockaddr_in_from);
 278                         continue;
 279                         }
 280                 /* Not yet initialized by 'probe' reply - drop it. */
 281                 if (probe)
 282                         continue;
 283
 284                 /* FIXME: Performance: Ugly search... */
 285                 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 286                         client=clientl->data;
 287                         if (client==master)
 288                                 continue;
 289                         if (1
 290                                         && client->sockaddr_in_from.sin_family     ==sockaddr_in_from.sin_family
 291                                         && client->sockaddr_in_from.sin_port       ==sockaddr_in_from.sin_port
 292                                         && client->sockaddr_in_from.sin_addr.s_addr==sockaddr_in_from.sin_addr.s_addr)
 293                                 break;
 294                         }
 295                 if (!clientl) {
 296                         client=client_new();
 297                         client->sockaddr_in_from=sockaddr_in_from;
 298                         }
 299                 client_touch(client,CLIENT_TIMEOUT_SEC);
 300                 UDPGATE_MEMZERO(&sockaddr_in_server);
 301                 sockaddr_in_server.sin_family=AF_INET;
 302                 sockaddr_in_server.sin_port=htons(SERVER_PORT);
 303                 sockaddr_in_server.sin_addr.s_addr=htonl(SERVER_INADDR);
 304                 /* FIXME: errors checking */
 305                 sendto(
 306                                 client->gpollfd.fd,     /* s */
 307                                 packet, /* msg */
 308                                 gotlen, /* len */
 309                                 0,      /* flags */
 310                                 (struct sockaddr *)&sockaddr_in_server, /* to */
 311                                 sizeof(sockaddr_in_server));    /* tolen */
 312                 }
 313 }
 314
 315 static void handle_probe(struct client *probe)
 316 {
 317         g_return_if_fail(probe!=NULL);
 318
 319         for (;;) {
 320 ssize_t gotlen;
 321 struct sockaddr_in sockaddr_in_from;
 322 char packet[0x10000];
 323 socklen_t sockaddr_in_from_length;
 324
 325                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 326                 if (-1==(gotlen=recvfrom(
 327                                 master->gpollfd.fd,     /* s */
 328                                 packet, /* buf */
 329                                 sizeof(packet), /* len */
 330                                 0,      /* flags */
 331                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 332                                 &sockaddr_in_from_length)))     /* fromlen */
 333                         break;
 334                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 335                         continue;
 336
 337                 /* Probe socket should have no response; maybe some ICMP errors - ignored. */
 338                 }
 339 }
 340
 341 static void handle_client(struct client *client)
 342 {
 343         g_return_if_fail(client!=NULL);
 344         g_return_if_fail(master!=NULL);
 345
 346         for (;;) {
 347 ssize_t gotlen;
 348 struct sockaddr_in sockaddr_in_from;
 349 char packet [0x10000];
 350 socklen_t sockaddr_in_from_length;
 351
 352                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 353                 if (-1==(gotlen=recvfrom(
 354                                 client->gpollfd.fd,     /* s */
 355                                 packet, /* buf */
 356                                 sizeof(packet), /* len */
 357                                 0,      /* flags */
 358                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 359                                 &sockaddr_in_from_length)))     /* fromlen */
 360                         break;
 361                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 362                         continue;
 363                 client_touch(client,CLIENT_TIMEOUT_SEC);
 364                 /* FIXME: errors checking */
 365                 sendto(
 366                                 master->gpollfd.fd,     /* s */
 367                                 packet, /* msg */
 368                                 gotlen, /* len */
 369                                 0,      /* flags */
 370                                 (struct sockaddr *)&client->sockaddr_in_from,   /* to */
 371                                 sizeof(client->sockaddr_in_from));      /* tolen */
 372                 }
 373 }
 374
 375 static gboolean sock_source_callback(gpointer data /* unused */)
 376 {
 377 GList *clientl;
 378
 379         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 380 struct client *client=clientl->data;
 381
 382                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS) {
 383                         /**/ if (client==master)
 384                                 handle_master(client);
 385                         else if (client==probe)
 386                                 handle_probe(client);
 387                         else
 388                                 handle_client(client);
 389                         }
 390                 }
 391
 392         return TRUE; /* the source should be kept active */
 393 }
 394
 395 static gboolean sock_source_prepare(GSource *source,gint *timeout)
 396 {
 397         *timeout=-1;
 398
 399         return FALSE;
 400 }
 401
 402 static gboolean sock_source_check(GSource *source)
 403 {
 404 GList *clientl;
 405
 406         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 407 struct client *client=clientl->data;
 408
 409                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS)
 410                         return TRUE;
 411                 }
 412         return FALSE;
 413 }
 414
 415 static gboolean sock_source_dispatch(GSource *source,GSourceFunc callback,gpointer user_data)
 416 {
 417         g_assert(callback!=NULL);
 418         return (*callback)(user_data);
 419 }
 420
 421 static GSourceFuncs sock_source_watch_funcs={
 422                 sock_source_prepare,
 423                 sock_source_check,
 424                 sock_source_dispatch,
 425                 NULL, /* finalize */
 426                 };
 427
 428 static void sock_gsource_destroy(void)
 429 {
 430         while (sock_client_list)
 431                 client_destroy(sock_client_list->data);
 432
 433         g_assert(master==NULL);
 434         g_assert(probe==NULL);
 435
 436         if (sock_gsource) {
 437                 g_source_destroy(sock_gsource);
 438                 sock_gsource=NULL;
 439                 }
 440
 441         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 442 }
 443
 444 static gboolean sock_gsource_new(void)
 445 {
 446         if (sock_gsource)
 447                 return TRUE;
 448
 449         g_assert(sock_client_list==NULL);
 450
 451         /* attach sock_source_callback() to watch for any abnormalities
 452          * on our open pipe 'parentheart_fds' and terminate the child if parent dies.
 453          */
 454         if (!(sock_gsource=g_source_new(&sock_source_watch_funcs,sizeof(GSource)))) {
 455                 g_warning("g_source_new(): %m");
 456                 return FALSE;
 457                 }
 458         g_source_set_callback(
 459                         sock_gsource,  /* source */
 460                         sock_source_callback,  /* func */
 461                         NULL, /* data */
 462                         NULL);  /* notify */
 463         if (!g_source_attach(   /* returns 'guint' id */
 464                         sock_gsource,  /* source */
 465                         NULL)) {        /* context; NULL means 'default context' */
 466                 g_warning("g_source_attach(gsource,NULL): %m");
 467                 sock_gsource_destroy();
 468                 return FALSE;
 469                 }
 470         return TRUE;
 471 }
 472
 473 static struct client *client_new(void)
 474 {
 475 struct client *client;
 476 static unsigned long oneul=1;
 477 int sock;
 478
 479         if (!sock_gsource_new())
 480                 return FALSE;
 481
 482         if (-1==(sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP))) {
 483                 g_warning("socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP): %m");
 484                 return NULL;
 485                 }
 486         if (ioctl(sock,FIONBIO,&oneul)) {       /* non-blocking mode */
 487                 g_warning("ioctl(sock,FIONBIO,&1): %m");
 488                 close(sock);    /* errors ignored */
 489                 return NULL;
 490                 }
 491
 492         udpgate_new(client);
 493         client->gpollfd.fd=sock;
 494         client->gpollfd.events=SOCK_SOURCE_CHECK_EVENTS;
 495         client->gpollfd.revents=0;
 496         client->timeout_id=0;
 497         sock_client_list=g_list_prepend(sock_client_list,client);
 498         g_source_add_poll(sock_gsource,&client->gpollfd);
 499
 500         if (optarg_verbose)
 501                 g_message(_("Client fd %d created"),client->gpollfd.fd);
 502
 503         return client;
 504 }
 505
 506 static void client_destroy(struct client *client)
 507 {
 508         g_return_if_fail(client!=NULL);
 509
 510         if (!sock_gsource_new())
 511                 return;
 512
 513         if (optarg_verbose)
 514                 g_message(_("Client fd %d timeout id %d destroy enter"),client->gpollfd.fd,client->timeout_id);
 515
 516         if (client==master) {
 517                 master=NULL;
 518                 g_assert(client->timeout_id==0);
 519                 }
 520         else {
 521                 if (client==probe)
 522                         probe=NULL;
 523                 client_timeout_remove(client);
 524                 }
 525
 526         g_source_remove_poll(sock_gsource,&client->gpollfd);
 527         sock_client_list=g_list_remove(sock_client_list,client);
 528         close(client->gpollfd.fd);      /* errors ignored */
 529
 530         if (optarg_verbose)
 531                 g_message(_("Client fd %d timeout id %d destroy finish"),client->gpollfd.fd,client->timeout_id);
 532
 533         g_free(client);
 534 }
 535
 536 static gboolean probe_send(struct client *probe,gint port_local)
 537 {
 538 struct sockaddr_in sockaddr_in_server;
 539 GHashTable *probe_hash;
 540 gpointer packet;
 541 size_t packet_length;
 542
 543         g_return_val_if_fail(probe!=NULL,FALSE);
 544
 545         probe_unique=g_random_int();
 546
 547         probe_hash=g_hash_table_new(
 548                         g_direct_hash,  /* hash_func */
 549                         g_direct_equal);        /* key_equal_func */
 550         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_PORT) ,GUINT_TO_POINTER(port_local));
 551         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),GUINT_TO_POINTER(probe_unique));
 552         packet=packet_assembly(&packet_length,probe_hash);
 553         g_hash_table_destroy(probe_hash);
 554         if (!packet)
 555                 return FALSE;
 556
 557         UDPGATE_MEMZERO(&sockaddr_in_server);
 558         sockaddr_in_server.sin_family=AF_INET;
 559         sockaddr_in_server.sin_port=htons(PROBE_PORT);
 560         sockaddr_in_server.sin_addr.s_addr=htonl(PROBE_INADDR);
 561         /* FIXME: errors checking */
 562         sendto(
 563                         probe->gpollfd.fd,      /* s */
 564                         packet, /* msg */
 565                         packet_length,  /* len */
 566                         0,      /* flags */
 567                         (struct sockaddr *)&sockaddr_in_server, /* to */
 568                         sizeof(sockaddr_in_server));    /* tolen */
 569
 570         return TRUE;
 571 }
 572
 573 static gboolean master_start(gint port)
 574 {
 575 struct sockaddr_in sockaddr_in;
 576
 577         g_return_val_if_fail(port>=0,FALSE);
 578         g_return_val_if_fail(master==NULL,FALSE);
 579
 580         /* Setup 'master': */
 581         if (!(master=client_new()))
 582                 return FALSE;
 583         UDPGATE_MEMZERO(&sockaddr_in);
 584         sockaddr_in.sin_family=AF_INET;
 585         sockaddr_in.sin_port=htons(port);
 586         sockaddr_in.sin_addr.s_addr=htonl(INADDR_ANY);
 587         if (bind(master->gpollfd.fd,(struct sockaddr *)&sockaddr_in,sizeof(sockaddr_in))) {
 588                 g_warning("bind(sock,{AF_INET,INADDR_ANY:%d}): %m",(int)port);
 589                 return FALSE;
 590                 }
 591         return TRUE;
 592 }
 593
 594 static gboolean probe_start(gint port)
 595 {
 596         g_return_val_if_fail(port>=0,FALSE);
 597         g_return_val_if_fail(probe==NULL,FALSE);
 598
 599         /* Setup 'probe': */
 600         if (!(probe=client_new()))
 601                 return FALSE;
 602         port_local=port;
 603         if (!probe_send(probe,port)) {
 604                 client_destroy(probe);
 605                 return FALSE;
 606                 }
 607         probe_timeout_sec_now=PROBE_TIMEOUT_SEC_BASE;
 608         client_touch(probe,probe_timeout_sec_now);      /* timeout */
 609         return TRUE;
 610 }
 611
 612 gboolean network_start(gint port)
 613 {
 614 pid_t daemon_pid;
 615
 616         g_return_val_if_fail(port>=0,FALSE);
 617
 618         if ((pid_t)-1!=(daemon_pid=is_daemon_running())) {
 619                 g_warning(_("Cannot start network daemon: Daemon is already running on PID %d"),(int)daemon_pid);
 620                 return FALSE;
 621                 }
 622         if (!master_start(port)) {
 623                 sock_gsource_destroy();
 624                 return FALSE;
 625                 }
 626         if (!probe_start(port)) {
 627                 sock_gsource_destroy();
 628                 return FALSE;
 629                 }
 630         write_daemon_running(getpid()); /* errors ignored */
 631         if (network_notify_hostip)
 632                 (*network_notify_hostip)(0);
 633         return TRUE;
 634 }
 635
 636 gboolean optarg_port_set_string(const gchar *port_string)
 637 {
 638 char *endp;
 639 long port_long;
 640
 641         g_return_val_if_fail(port_string!=NULL,FALSE);
 642
 643         port_long=strtol(port_string,&endp,0);
 644         if (endp && *endp) {
 645                 g_warning(_("Invalid port specification, offending string: %s"),endp);
 646                 return FALSE;
 647                 }
 648         if (port_long<1 || port_long>=G_MAXINT || (endp && *endp)) {
 649                 g_warning(_("Invalid port integer number specification (%ld)"),port_long);
 650                 return FALSE;
 651                 }
 652         optarg_port=port_long;
 653         return TRUE;
 654 }
 655
 656 gboolean network_stop(void)
 657 {
 658 pid_t daemon_pid;
 659 int errno_save;
 660
 661         if ((pid_t)-1==(daemon_pid=is_daemon_running())) {
 662                 g_warning(_("Cannot stop network daemon: Daemon is not running"));
 663                 return FALSE;
 664                 }
 665         if (daemon_pid==getpid()) {
 666                 sock_gsource_destroy();
 667                 goto ok;
 668                 }
 669         errno=0;
 670         kill(daemon_pid,SIGKILL);
 671         errno_save=errno;
 672         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 673         if (errno_save)  {
 674                 g_warning(udpgate_printf_alloca(_("Unable to stop the daemon at PID %d: %s"),
 675                                 (int)daemon_pid,strerror(errno_save)));
 676                 return FALSE;
 677                 }
 678 ok:
 679         if (network_notify_hostip)
 680                 (*network_notify_hostip)(0);
 681         return TRUE;
 682 }
 683
 684 static GMainLoop *gmainloop;
 685 static void network_detach_network_notify_hostip(guint32 hostip_guint32)
 686 {
 687         if (!hostip_guint32)
 688                 g_main_loop_quit(gmainloop);
 689 }
 690
 691 gboolean network_detach(void)
 692 {
 693 pid_t daemon_pid,forked_pid;
 694
 695         if ((pid_t)-1==(daemon_pid=is_daemon_running()))
 696                 return TRUE;
 697         if (getpid()!=daemon_pid)
 698                 return TRUE;
 699         if (!optarg_no_fork) {
 700                 if ((pid_t)-1==(forked_pid=fork())) {
 701                         g_warning("fork(2): %m");
 702                         return FALSE;
 703                         }
 704                 if (forked_pid) {
 705                         /* parent */
 706                         return TRUE;
 707                         }
 708                 write_daemon_running(getpid()); /* errors ignored */
 709                 optarg_verbose=0;
 710                 close(STDIN_FILENO);
 711                 close(STDOUT_FILENO);
 712                 close(STDERR_FILENO);
 713                 setpgrp();
 714                 setsid();
 715                 }
 716
 717         network_notify_hostip=network_detach_network_notify_hostip;
 718         gmainloop=g_main_loop_new(
 719                         NULL,   /* context */
 720                         TRUE);  /* is_running; ignored */
 721         g_main_loop_run(gmainloop);     /* loop */
 722         /* Unable to contact the server, aborting. */
 723         return FALSE;
 724 }