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 #include "pathname.h"
  43
  44
  45 /* Config: */
  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 0xC37AD054        /* mms2.org = 195.122.208.84; 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 static G_CONST_RETURN gchar *pid_pathname(void)
  61 {
  62 static const gchar *static_pathname;
  63 static const char *user_val;
  64
  65         if (!static_pathname)
  66                 user_val=getenv("USER");
  67         return pathname_find(&static_pathname,
  68                         G_STRINGIFY(LOCALSTATEDIR) "/run",PACKAGE ".pid",
  69                         (!user_val ? NULL : "/tmp"),
  70                                         (!user_val ? NULL : udpgate_printf_alloca(".%s-%s.pid",user_val,PACKAGE)),
  71                         NULL);
  72 }
  73
  74
  75 struct client {
  76         GPollFD gpollfd;
  77         struct sockaddr_in sockaddr_in_from;
  78         guint timeout_id;
  79         };
  80
  81 static GSource *sock_gsource;
  82
  83 static GList *sock_client_list; /* of 'struct client *', incl. 'master' and 'probe' */
  84 static struct client *master;   /* no 'timeout' permitted */
  85 static struct client *probe;    /* 'timeout' permitted */
  86 static guint32 probe_unique;
  87 static guint probe_timeout_sec_now;
  88 guint probe_timeout_sec_max=G_MAXUINT;
  89 static gint port_local; /* for 'probe' resends */
  90
  91 static gboolean write_daemon_running(pid_t pid);
  92
  93 pid_t is_daemon_running(void)
  94 {
  95 FILE *f;
  96 char buf[LINE_MAX],*got;
  97 int pid_int;
  98
  99         if (sock_gsource)
 100                 return getpid();
 101
 102         if (!(f=fopen(pid_pathname(),"r")))
 103                 goto err;
 104         got=fgets(buf,sizeof(buf),f);
 105         fclose(f);      /* FIXME: error ignored */
 106         if (got!=buf) {
 107 err_unlink:
 108                 write_daemon_running((pid_t)-1);        /* unlink */
 109 err:
 110                 return (pid_t)-1;
 111                 }
 112         pid_int=atoi(buf);
 113         if (pid_int<=1)
 114                 goto err_unlink;
 115         if (kill((pid_t)pid_int,0)) {
 116                 if (errno==ESRCH)
 117                         goto err_unlink;
 118                 goto err;
 119                 }
 120         return (pid_t)pid_int;
 121 }
 122
 123 static gboolean write_daemon_running(pid_t pid)
 124 {
 125 FILE *f;
 126
 127         if (pid==(pid_t)-1) {
 128                 if (unlink(pid_pathname())) {
 129                         if (errno!=ENOENT)
 130                                 g_warning(_("Error removing PID file \"%s\": %m"),pid_pathname());
 131                         return FALSE;
 132                         }
 133                 return TRUE;
 134                 }
 135         if (!(f=fopen(pid_pathname(),"w"))) {
 136 static gboolean once=TRUE;
 137
 138                 if (once) {
 139                         once=FALSE;
 140                         g_warning(_("Error writing PID %d to \"%s\": %m"),(int)pid,pid_pathname());
 141                         }
 142                 return FALSE;
 143                 }
 144         fprintf(f,"%d\n",(int)pid);     /* errors ignored */
 145         fclose(f);      /* FIXME: error ignored */
 146         return TRUE;
 147 }
 148
 149 static void client_timeout_remove(struct client *client)
 150 {
 151         g_return_if_fail(client!=NULL);
 152         g_return_if_fail(client!=master);
 153
 154         if (client->timeout_id) {
 155 gboolean errgboolean;
 156
 157                 if (optarg_verbose)
 158                         g_message(_("Client fd %d removed timeout id %d"),client->gpollfd.fd,client->timeout_id);
 159                 errgboolean=g_source_remove(client->timeout_id);
 160                 g_assert(errgboolean==TRUE);
 161                 client->timeout_id=0;
 162                 }
 163 }
 164
 165 static gboolean client_touch_timeout(struct client *client);
 166
 167 static void client_touch(struct client *client,guint timeout_sec)
 168 {
 169         g_return_if_fail(client!=NULL);
 170         g_return_if_fail(client!=master);
 171         g_return_if_fail(timeout_sec>0);
 172
 173         client_timeout_remove(client);
 174         client->timeout_id=g_timeout_add(
 175                         timeout_sec*1000,       /* interval; msec */
 176                         (GSourceFunc)client_touch_timeout,      /* function */
 177                         client);        /* data */
 178         if (optarg_verbose)
 179                 g_message(_("Client fd %d new timeout id %d"),client->gpollfd.fd,client->timeout_id);
 180         g_assert(client->timeout_id!=0);
 181 }
 182
 183 static void client_destroy(struct client *client);
 184 static gboolean probe_send(struct client *probe,gint port_local);
 185
 186 static gboolean client_touch_timeout(struct client *client)
 187 {
 188         g_return_val_if_fail(client!=NULL,FALSE);       /* FALSE=>should be removed */
 189         g_return_val_if_fail(client!=master,FALSE);     /* FALSE=>should be removed */
 190
 191         if (optarg_verbose)
 192                 g_message(_("Client fd %d timeout id %d occured/entered"),client->gpollfd.fd,client->timeout_id);
 193
 194         /* Do not destroy the timeout in client_destroy().
 195          * It would crash GLib - we remove it be returning FALSE from here.
 196          */
 197         g_assert(client->timeout_id!=0);
 198         client->timeout_id=0;
 199
 200         if (client==probe) {
 201                 if (probe_timeout_sec_now<probe_timeout_sec_max) {
 202                         probe_timeout_sec_now*=PROBE_TIMEOUT_SEC_BASE;
 203                         g_assert(probe_timeout_sec_max==G_MAXUINT || probe_timeout_sec_max<PROBE_TIMEOUT_SEC_MAX);
 204                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,probe_timeout_sec_max);
 205                         probe_timeout_sec_now=MIN(probe_timeout_sec_now,PROBE_TIMEOUT_SEC_MAX);
 206                         if (probe_send(probe,port_local)) {
 207                                 client_touch(probe,probe_timeout_sec_now);      /* timeout */
 208                                 return FALSE;   /* GSource should be removed */
 209                                 }
 210                         /* failure FALLTHRU */
 211                         }
 212                 network_stop();
 213                 /* Never destroy 'client' now - it has been destroyed by network_stop()! */
 214                 g_warning(_("No probe response from the server, stopping the daemon. Please check your public Internet connectivity."));
 215                 }
 216         else {
 217                 client_destroy(client);
 218                 }
 219
 220         if (optarg_verbose)
 221                 g_message(_("Client timeout occurance finish"));
 222
 223         return FALSE;   /* GSource should be removed */
 224 }
 225
 226 static void handle_master_probe(const void *packet,size_t gotlen,const struct sockaddr_in *sockaddr_in_from)
 227 {
 228 GHashTable *got_hash;
 229 gpointer got_unique_gpointer;
 230 gpointer hostip_gpointer;
 231 guint32 hostip_guint32;
 232
 233         g_return_if_fail(packet!=NULL);
 234         g_return_if_fail(sockaddr_in_from!=NULL);
 235
 236         if (!probe)
 237                 return;
 238
 239         if (!(got_hash=packet_disassembly(packet,gotlen)))
 240                 return;
 241         if (!(g_hash_table_lookup_extended(
 242                         got_hash,       /* hash_table */
 243                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),        /* lookup_key */
 244                         NULL,   /* orig_key */
 245                         &got_unique_gpointer))) {
 246 err_packet_disassembly_destroy_got_hash:
 247                 packet_disassembly_destroy(got_hash);
 248                 return;
 249                 }
 250         if (GPOINTER_TO_UINT(got_unique_gpointer)!=probe_unique)
 251                 goto err_packet_disassembly_destroy_got_hash;
 252         if (!(g_hash_table_lookup_extended(
 253                         got_hash,       /* hash_table */
 254                         GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_INADDR),       /* lookup_key */
 255                         NULL,   /* orig_key */
 256                         &hostip_gpointer)))
 257                 goto err_packet_disassembly_destroy_got_hash;
 258         hostip_guint32=GPOINTER_TO_UINT(hostip_gpointer);
 259         packet_disassembly_destroy(got_hash);
 260
 261         client_destroy(probe);
 262         if (network_notify_hostip)
 263                 (*network_notify_hostip)(hostip_guint32);
 264 }
 265
 266 static struct client *client_new(void);
 267
 268 static void handle_master(struct client *master)
 269 {
 270         g_return_if_fail(master!=NULL);
 271
 272         for (;;) {
 273 char packet[0x10000];
 274 ssize_t gotlen;
 275 struct sockaddr_in sockaddr_in_from;
 276 struct client *client=NULL      /* Prevent false positive: might be used uninitialized */;
 277 struct sockaddr_in sockaddr_in_server;
 278 socklen_t sockaddr_in_from_length;
 279 GList *clientl;
 280
 281                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 282                 if (-1==(gotlen=recvfrom(
 283                                 master->gpollfd.fd,     /* s */
 284                                 packet, /* buf */
 285                                 sizeof(packet), /* len */
 286                                 0,      /* flags */
 287                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 288                                 &sockaddr_in_from_length)))     /* fromlen */
 289                         break;
 290
 291                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 292                         continue;
 293
 294                 if (packet_recognized(packet,gotlen)) {
 295                         handle_master_probe(packet,gotlen,&sockaddr_in_from);
 296                         continue;
 297                         }
 298                 /* Not yet initialized by 'probe' reply - drop it. */
 299                 if (probe) {
 300                         if (optarg_verbose)
 301                                 g_message(_("Data packet received from %s but no probe reply yet; dropping packet."),
 302                                                 SOCKADDR_IN_TO_STRING(&sockaddr_in_from));
 303                         continue;
 304                         }
 305
 306                 /* FIXME: Performance: Ugly search... */
 307                 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 308                         client=clientl->data;
 309                         if (client==master)
 310                                 continue;
 311                         if (1
 312                                         && client->sockaddr_in_from.sin_family     ==sockaddr_in_from.sin_family
 313                                         && client->sockaddr_in_from.sin_port       ==sockaddr_in_from.sin_port
 314                                         && client->sockaddr_in_from.sin_addr.s_addr==sockaddr_in_from.sin_addr.s_addr)
 315                                 break;
 316                         }
 317                 if (!clientl) {
 318                         client=client_new();
 319                         client->sockaddr_in_from=sockaddr_in_from;
 320                         }
 321                 client_touch(client,CLIENT_TIMEOUT_SEC);
 322                 UDPGATE_MEMZERO(&sockaddr_in_server);
 323                 sockaddr_in_server.sin_family=AF_INET;
 324                 sockaddr_in_server.sin_port=htons(SERVER_PORT);
 325                 sockaddr_in_server.sin_addr.s_addr=htonl(SERVER_INADDR);
 326                 /* FIXME: errors checking */
 327                 sendto(
 328                                 client->gpollfd.fd,     /* s */
 329                                 packet, /* msg */
 330                                 gotlen, /* len */
 331                                 0,      /* flags */
 332                                 (struct sockaddr *)&sockaddr_in_server, /* to */
 333                                 sizeof(sockaddr_in_server));    /* tolen */
 334                 }
 335 }
 336
 337 static void handle_probe(struct client *probe)
 338 {
 339         g_return_if_fail(probe!=NULL);
 340
 341         for (;;) {
 342 ssize_t gotlen;
 343 struct sockaddr_in sockaddr_in_from;
 344 char packet[0x10000];
 345 socklen_t sockaddr_in_from_length;
 346
 347                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 348                 if (-1==(gotlen=recvfrom(
 349                                 master->gpollfd.fd,     /* s */
 350                                 packet, /* buf */
 351                                 sizeof(packet), /* len */
 352                                 0,      /* flags */
 353                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 354                                 &sockaddr_in_from_length)))     /* fromlen */
 355                         break;
 356                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 357                         continue;
 358
 359                 /* Probe socket should have no response; maybe some ICMP errors - ignored. */
 360                 }
 361 }
 362
 363 static void handle_client(struct client *client)
 364 {
 365         g_return_if_fail(client!=NULL);
 366         g_return_if_fail(master!=NULL);
 367
 368         for (;;) {
 369 ssize_t gotlen;
 370 struct sockaddr_in sockaddr_in_from;
 371 char packet [0x10000];
 372 socklen_t sockaddr_in_from_length;
 373
 374                 sockaddr_in_from_length=sizeof(sockaddr_in_from);
 375                 if (-1==(gotlen=recvfrom(
 376                                 client->gpollfd.fd,     /* s */
 377                                 packet, /* buf */
 378                                 sizeof(packet), /* len */
 379                                 0,      /* flags */
 380                                 (struct sockaddr *)&sockaddr_in_from,   /* from */
 381                                 &sockaddr_in_from_length)))     /* fromlen */
 382                         break;
 383                 if (sockaddr_in_from_length!=sizeof(sockaddr_in_from))  /* FIXME: errors reporting */
 384                         continue;
 385                 client_touch(client,CLIENT_TIMEOUT_SEC);
 386                 /* FIXME: errors checking */
 387                 sendto(
 388                                 master->gpollfd.fd,     /* s */
 389                                 packet, /* msg */
 390                                 gotlen, /* len */
 391                                 0,      /* flags */
 392                                 (struct sockaddr *)&client->sockaddr_in_from,   /* to */
 393                                 sizeof(client->sockaddr_in_from));      /* tolen */
 394                 }
 395 }
 396
 397 static gboolean sock_source_callback(gpointer data /* unused */)
 398 {
 399 GList *clientl;
 400
 401         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 402 struct client *client=clientl->data;
 403
 404                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS) {
 405                         /**/ if (client==master)
 406                                 handle_master(client);
 407                         else if (client==probe)
 408                                 handle_probe(client);
 409                         else
 410                                 handle_client(client);
 411                         }
 412                 }
 413
 414         return TRUE; /* the source should be kept active */
 415 }
 416
 417 static gboolean sock_source_prepare(GSource *source,gint *timeout)
 418 {
 419         *timeout=-1;
 420
 421         return FALSE;
 422 }
 423
 424 static gboolean sock_source_check(GSource *source)
 425 {
 426 GList *clientl;
 427
 428         for (clientl=sock_client_list;clientl;clientl=clientl->next) {
 429 struct client *client=clientl->data;
 430
 431                 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS)
 432                         return TRUE;
 433                 }
 434         return FALSE;
 435 }
 436
 437 static gboolean sock_source_dispatch(GSource *source,GSourceFunc callback,gpointer user_data)
 438 {
 439         g_assert(callback!=NULL);
 440         return (*callback)(user_data);
 441 }
 442
 443 static GSourceFuncs sock_source_watch_funcs={
 444                 sock_source_prepare,
 445                 sock_source_check,
 446                 sock_source_dispatch,
 447                 NULL, /* finalize */
 448                 };
 449
 450 static void sock_gsource_destroy(void)
 451 {
 452         while (sock_client_list)
 453                 client_destroy(sock_client_list->data);
 454
 455         g_assert(master==NULL);
 456         g_assert(probe==NULL);
 457
 458         if (sock_gsource) {
 459                 g_source_destroy(sock_gsource);
 460                 sock_gsource=NULL;
 461                 }
 462
 463         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 464 }
 465
 466 static gboolean sock_gsource_new(void)
 467 {
 468         if (sock_gsource)
 469                 return TRUE;
 470
 471         g_assert(sock_client_list==NULL);
 472
 473         /* attach sock_source_callback() to watch for any abnormalities
 474          * on our open pipe 'parentheart_fds' and terminate the child if parent dies.
 475          */
 476         if (!(sock_gsource=g_source_new(&sock_source_watch_funcs,sizeof(GSource)))) {
 477                 g_warning("g_source_new(): %m");
 478                 return FALSE;
 479                 }
 480         g_source_set_callback(
 481                         sock_gsource,  /* source */
 482                         sock_source_callback,  /* func */
 483                         NULL, /* data */
 484                         NULL);  /* notify */
 485         if (!g_source_attach(   /* returns 'guint' id */
 486                         sock_gsource,  /* source */
 487                         NULL)) {        /* context; NULL means 'default context' */
 488                 g_warning("g_source_attach(gsource,NULL): %m");
 489                 sock_gsource_destroy();
 490                 return FALSE;
 491                 }
 492         return TRUE;
 493 }
 494
 495 static struct client *client_new(void)
 496 {
 497 struct client *client;
 498 static unsigned long oneul=1;
 499 int sock;
 500
 501         if (!sock_gsource_new())
 502                 return FALSE;
 503
 504         if (-1==(sock=socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP))) {
 505                 g_warning("socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP): %m");
 506                 return NULL;
 507                 }
 508         if (ioctl(sock,FIONBIO,&oneul)) {       /* non-blocking mode */
 509                 g_warning("ioctl(sock,FIONBIO,&1): %m");
 510                 close(sock);    /* errors ignored */
 511                 return NULL;
 512                 }
 513
 514         udpgate_new(client);
 515         client->gpollfd.fd=sock;
 516         client->gpollfd.events=SOCK_SOURCE_CHECK_EVENTS;
 517         client->gpollfd.revents=0;
 518         client->timeout_id=0;
 519         sock_client_list=g_list_prepend(sock_client_list,client);
 520         g_source_add_poll(sock_gsource,&client->gpollfd);
 521
 522         if (optarg_verbose)
 523                 g_message(_("Client fd %d created"),client->gpollfd.fd);
 524
 525         return client;
 526 }
 527
 528 static void client_destroy(struct client *client)
 529 {
 530         g_return_if_fail(client!=NULL);
 531
 532         if (!sock_gsource_new())
 533                 return;
 534
 535         if (optarg_verbose)
 536                 g_message(_("Client fd %d timeout id %d destroy enter"),client->gpollfd.fd,client->timeout_id);
 537
 538         if (client==master) {
 539                 master=NULL;
 540                 g_assert(client->timeout_id==0);
 541                 }
 542         else {
 543                 if (client==probe)
 544                         probe=NULL;
 545                 client_timeout_remove(client);
 546                 }
 547
 548         g_source_remove_poll(sock_gsource,&client->gpollfd);
 549         sock_client_list=g_list_remove(sock_client_list,client);
 550         close(client->gpollfd.fd);      /* errors ignored */
 551
 552         if (optarg_verbose)
 553                 g_message(_("Client fd %d timeout id %d destroy finish"),client->gpollfd.fd,client->timeout_id);
 554
 555         g_free(client);
 556 }
 557
 558 static gboolean probe_send(struct client *probe,gint port_local)
 559 {
 560 struct sockaddr_in sockaddr_in_server;
 561 GHashTable *probe_hash;
 562 gpointer packet;
 563 size_t packet_length;
 564
 565         g_return_val_if_fail(probe!=NULL,FALSE);
 566
 567         probe_unique=g_random_int();
 568
 569         probe_hash=g_hash_table_new(
 570                         g_direct_hash,  /* hash_func */
 571                         g_direct_equal);        /* key_equal_func */
 572         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_CLIENT_PORT) ,GUINT_TO_POINTER(port_local));
 573         g_hash_table_insert(probe_hash,GUINT_TO_POINTER(PACKET_ELEM_TYPE_DATA_GUINT32),GUINT_TO_POINTER(probe_unique));
 574         packet=packet_assembly(&packet_length,probe_hash);
 575         g_hash_table_destroy(probe_hash);
 576         if (!packet)
 577                 return FALSE;
 578
 579         UDPGATE_MEMZERO(&sockaddr_in_server);
 580         sockaddr_in_server.sin_family=AF_INET;
 581         sockaddr_in_server.sin_port=htons(PROBE_PORT);
 582         sockaddr_in_server.sin_addr.s_addr=htonl(PROBE_INADDR);
 583         /* FIXME: errors checking */
 584         sendto(
 585                         probe->gpollfd.fd,      /* s */
 586                         packet, /* msg */
 587                         packet_length,  /* len */
 588                         0,      /* flags */
 589                         (struct sockaddr *)&sockaddr_in_server, /* to */
 590                         sizeof(sockaddr_in_server));    /* tolen */
 591
 592         return TRUE;
 593 }
 594
 595 static gboolean master_start(gint port)
 596 {
 597 struct sockaddr_in sockaddr_in;
 598 uint16_t port_use;
 599
 600         g_return_val_if_fail(port>=0,FALSE);
 601         g_return_val_if_fail(master==NULL,FALSE);
 602
 603         port_use=port;
 604         if (port < 0 || port_use != port) {
 605                 g_warning(_("Port value %d is not valid for IPv4!"),(int)port);
 606                 return FALSE;
 607                 }
 608
 609         /* Setup 'master': */
 610         if (!(master=client_new()))
 611                 return FALSE;
 612         UDPGATE_MEMZERO(&sockaddr_in);
 613         sockaddr_in.sin_family=AF_INET;
 614         sockaddr_in.sin_port=htons(port_use);
 615         sockaddr_in.sin_addr.s_addr=htonl(INADDR_ANY);
 616         if (bind(master->gpollfd.fd,(struct sockaddr *)&sockaddr_in,sizeof(sockaddr_in))) {
 617                 g_warning("bind(sock,{AF_INET,INADDR_ANY:%u}): %m",(unsigned)port_use);
 618                 return FALSE;
 619                 }
 620         return TRUE;
 621 }
 622
 623 static gboolean probe_start(gint port)
 624 {
 625         g_return_val_if_fail(port>=0,FALSE);
 626         g_return_val_if_fail(probe==NULL,FALSE);
 627
 628         /* Setup 'probe': */
 629         if (!(probe=client_new()))
 630                 return FALSE;
 631         port_local=port;
 632         if (!probe_send(probe,port)) {
 633                 client_destroy(probe);
 634                 return FALSE;
 635                 }
 636         probe_timeout_sec_now=PROBE_TIMEOUT_SEC_BASE;
 637         client_touch(probe,probe_timeout_sec_now);      /* timeout */
 638         return TRUE;
 639 }
 640
 641 gboolean network_start(gint port)
 642 {
 643 pid_t daemon_pid;
 644
 645         g_return_val_if_fail(port>=0,FALSE);
 646
 647         if ((pid_t)-1!=(daemon_pid=is_daemon_running())) {
 648                 g_warning(_("Cannot start network daemon: Daemon is already running on PID %d"),(int)daemon_pid);
 649                 return FALSE;
 650                 }
 651         if (!master_start(port)) {
 652                 sock_gsource_destroy();
 653                 return FALSE;
 654                 }
 655         if (!probe_start(port)) {
 656                 sock_gsource_destroy();
 657                 return FALSE;
 658                 }
 659         write_daemon_running(getpid()); /* errors ignored */
 660         if (network_notify_hostip)
 661                 (*network_notify_hostip)(0);
 662         return TRUE;
 663 }
 664
 665 gboolean optarg_port_set_string(const gchar *port_string)
 666 {
 667 char *endp;
 668 long port_long;
 669
 670         g_return_val_if_fail(port_string!=NULL,FALSE);
 671
 672         port_long=strtol(port_string,&endp,0);
 673         if (endp && *endp) {
 674                 g_warning(_("Invalid port specification, offending string: %s"),endp);
 675                 return FALSE;
 676                 }
 677         if (port_long<1 || port_long>=G_MAXINT || (endp && *endp)) {
 678                 g_warning(_("Invalid port integer number specification (%ld)"),port_long);
 679                 return FALSE;
 680                 }
 681         optarg_port=port_long;
 682         return TRUE;
 683 }
 684
 685 gboolean network_stop(void)
 686 {
 687 pid_t daemon_pid;
 688 int errno_save;
 689
 690         if ((pid_t)-1==(daemon_pid=is_daemon_running())) {
 691                 g_warning(_("Cannot stop network daemon: Daemon is not running"));
 692                 return FALSE;
 693                 }
 694         if (daemon_pid==getpid()) {
 695                 sock_gsource_destroy();
 696                 goto ok;
 697                 }
 698         errno=0;
 699         kill(daemon_pid,SIGKILL);
 700         errno_save=errno;
 701         write_daemon_running((pid_t)-1);        /* unlink; errors ignored */
 702         if (errno_save)  {
 703                 g_warning(udpgate_printf_alloca(_("Unable to stop the daemon at PID %d: %s"),
 704                                 (int)daemon_pid,strerror(errno_save)));
 705                 return FALSE;
 706                 }
 707 ok:
 708         if (network_notify_hostip)
 709                 (*network_notify_hostip)(0);
 710         return TRUE;
 711 }
 712
 713 static GMainLoop *gmainloop;
 714 static void network_detach_network_notify_hostip(guint32 hostip_guint32)
 715 {
 716         if (!hostip_guint32)
 717                 g_main_loop_quit(gmainloop);
 718 }
 719
 720 gboolean network_detach(void)
 721 {
 722 pid_t daemon_pid,forked_pid;
 723
 724         if ((pid_t)-1==(daemon_pid=is_daemon_running()))
 725                 return TRUE;
 726         if (getpid()!=daemon_pid)
 727                 return TRUE;
 728         if (!optarg_no_fork) {
 729                 if ((pid_t)-1==(forked_pid=fork())) {
 730                         g_warning("fork(2): %m");
 731                         return FALSE;
 732                         }
 733                 if (forked_pid) {
 734                         /* parent */
 735                         return TRUE;
 736                         }
 737                 write_daemon_running(getpid()); /* errors ignored */
 738                 optarg_verbose=0;
 739                 close(STDIN_FILENO);
 740                 close(STDOUT_FILENO);
 741                 close(STDERR_FILENO);
 742                 setpgrp();
 743                 setsid();
 744                 }
 745
 746         network_notify_hostip=network_detach_network_notify_hostip;
 747         gmainloop=g_main_loop_new(
 748                         NULL,   /* context */
 749                         TRUE);  /* is_running; ignored */
 750         g_main_loop_run(gmainloop);     /* loop */
 751         /* Unable to contact the server, aborting. */
 752         return FALSE;
 753 }