2 * UDP forwarding utility
3 * Copyright (C) 2004 Jan Kratochvil <project-udpforward@jankratochvil.net>
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
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.
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
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>
29 #include <sys/types.h>
32 #include <glib/giochannel.h>
33 #include <sys/ioctl.h>
35 #include <glib/galloca.h>
36 #include <glib/gprintf.h>
42 #define NETWORK_PATHNAME_PID "/var/run/udpforward.pid"
43 #define SOCK_SOURCE_CHECK_EVENTS (G_IO_IN) /* |G_IO_PRI */
44 #define SOCK_SOURCE_CHECK_REVENTS (SOCK_SOURCE_CHECK_EVENTS) /* |G_IO_ERR|G_IO_HUP|G_IO_NVAL */
45 #define SERVER_INADDR 0xEA021F51 /* paulina.vellum.cz = 81.31.2.234 */
46 #define SERVER_PORT 9201
47 #define CLIENT_TIMEOUT_SEC (5*60)
52 struct sockaddr_in sockaddr_in_from;
56 static GSource *sock_gsource;
58 static GList *sock_client_list; /* of 'struct client *' */
59 struct client *master;
61 static gboolean write_daemon_running(pid_t pid);
63 pid_t is_daemon_running(void)
66 char buf[LINE_MAX],*got;
72 if (!(f=fopen(NETWORK_PATHNAME_PID,"r")))
74 got=fgets(buf,sizeof(buf),f);
75 fclose(f); /* FIXME: error ignored */
78 write_daemon_running((pid_t)-1); /* unlink */
85 if (kill((pid_t)pid_int,0)) {
90 return (pid_t)pid_int;
93 static gboolean write_daemon_running(pid_t pid)
98 if (unlink(NETWORK_PATHNAME_PID)) {
99 g_warning(_("Error removing PID file \"%s\": %m"),NETWORK_PATHNAME_PID);
104 if (!(f=fopen(NETWORK_PATHNAME_PID,"w"))) {
105 g_warning(_("Error writing PID %d to \"%s\": %m"),(int)pid,NETWORK_PATHNAME_PID);
108 fprintf(f,"%d\n",(int)pid); /* errors ignored */
109 fclose(f); /* FIXME: error ignored */
113 static void client_timeout_remove(struct client *client)
115 g_return_if_fail(client!=NULL);
116 g_return_if_fail(client!=master);
118 if (client->timeout_id) {
119 gboolean errgboolean;
121 errgboolean=g_source_remove(client->timeout_id);
122 g_assert(errgboolean==TRUE);
123 client->timeout_id=0;
127 static gboolean client_touch_timeout(struct client *client);
129 static void client_touch(struct client *client)
131 g_return_if_fail(client!=NULL);
132 g_return_if_fail(client!=master);
134 client_timeout_remove(client);
135 client->timeout_id=g_timeout_add(
136 CLIENT_TIMEOUT_SEC*1000, /* interval; msec */
137 (GSourceFunc)client_touch_timeout, /* function */
139 g_assert(client->timeout_id!=0);
142 static void client_destroy(struct client *client);
144 static gboolean client_touch_timeout(struct client *client)
146 g_return_val_if_fail(client!=NULL,FALSE); /* FALSE=>should be removed */
147 g_return_val_if_fail(client!=master,FALSE); /* FALSE=>should be removed */
149 client_destroy(client);
151 return FALSE; /* GSource should be removed */
154 static struct client *client_new(void);
156 static void handle_master(struct client *master)
159 struct sockaddr_in sockaddr_in_from;
160 char packet[0x10000];
161 struct client *client;
162 struct sockaddr_in sockaddr_in_server;
163 socklen_t sockaddr_in_from_len;
165 g_return_if_fail(master!=NULL);
167 sockaddr_in_from_len=sizeof(sockaddr_in_from);
168 while (-1!=(gotlen=recvfrom(
169 master->gpollfd.fd, /* s */
171 sizeof(packet), /* len */
173 (struct sockaddr *)&sockaddr_in_from, /* from */
174 &sockaddr_in_from_len))) { /* fromlen */
177 if (sockaddr_in_from_len!=sizeof(sockaddr_in_from)) /* FIXME: errors reporting */
179 /* FIXME: Performance: Ugly search... */
180 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
181 client=clientl->data;
185 && client->sockaddr_in_from.sin_family ==sockaddr_in_from.sin_family
186 && client->sockaddr_in_from.sin_port ==sockaddr_in_from.sin_port
187 && client->sockaddr_in_from.sin_addr.s_addr==sockaddr_in_from.sin_addr.s_addr)
192 client->sockaddr_in_from=sockaddr_in_from;
194 client_touch(client);
195 UDPFORWARD_MEMZERO(&sockaddr_in_server);
196 sockaddr_in_server.sin_family=AF_INET;
197 sockaddr_in_server.sin_port=htons(SERVER_PORT);
198 sockaddr_in_server.sin_addr.s_addr=htonl(SERVER_INADDR);
199 /* FIXME: errors checking */
201 client->gpollfd.fd, /* s */
205 (struct sockaddr *)&sockaddr_in_server, /* to */
206 sizeof(sockaddr_in_server)); /* tolen */
210 static void handle_client(struct client *client)
213 struct sockaddr_in sockaddr_in_from;
214 char packet [0x10000];
215 socklen_t sockaddr_in_from_len;
217 g_return_if_fail(client!=NULL);
218 g_return_if_fail(master!=NULL);
220 while (-1!=(gotlen=recvfrom(
221 client->gpollfd.fd, /* s */
223 sizeof(packet), /* len */
225 (struct sockaddr *)&sockaddr_in_from, /* from */
226 &sockaddr_in_from_len))) { /* fromlen */
227 if (sockaddr_in_from_len!=sizeof(sockaddr_in_from)) /* FIXME: errors reporting */
229 client_touch(client);
230 /* FIXME: errors checking */
232 master->gpollfd.fd, /* s */
236 (struct sockaddr *)&client->sockaddr_in_from, /* to */
237 sizeof(client->sockaddr_in_from)); /* tolen */
241 static gboolean sock_source_callback(gpointer data /* unused */)
245 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
246 struct client *client=clientl->data;
248 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS) {
250 handle_master(client);
252 handle_client(client);
256 return TRUE; /* the source should be kept active */
259 static gboolean sock_source_prepare(GSource *source,gint *timeout)
266 static gboolean sock_source_check(GSource *source)
270 for (clientl=sock_client_list;clientl;clientl=clientl->next) {
271 struct client *client=clientl->data;
273 if (client->gpollfd.revents&SOCK_SOURCE_CHECK_REVENTS)
279 static gboolean sock_source_dispatch(GSource *source,GSourceFunc callback,gpointer user_data)
281 g_assert(callback!=NULL);
282 return (*callback)(user_data);
285 static GSourceFuncs sock_source_watch_funcs={
288 sock_source_dispatch,
292 static void sock_gsource_destroy(void)
294 while (sock_client_list)
295 client_destroy(sock_client_list->data);
297 g_assert(master==NULL);
300 g_source_destroy(sock_gsource);
305 static gboolean sock_gsource_new(void)
310 g_assert(sock_client_list==NULL);
312 /* attach sock_source_callback() to watch for any abnormalities
313 * on our open pipe 'parentheart_fds' and terminate the child if parent dies.
315 if (!(sock_gsource=g_source_new(&sock_source_watch_funcs,sizeof(GSource)))) {
316 g_warning("g_source_new(): %m");
319 g_source_set_callback(
320 sock_gsource, /* source */
321 sock_source_callback, /* func */
324 if (!g_source_attach( /* returns 'guint' id */
325 sock_gsource, /* source */
326 NULL)) { /* context; NULL means 'default context' */
327 g_warning("g_source_attach(gsource,NULL): %m");
328 sock_gsource_destroy();
334 static struct client *client_new(void)
336 struct client *client;
337 static unsigned long oneul=1;
340 if (!sock_gsource_new())
343 if (-1==(sock=socket(AF_INET,SOCK_DGRAM,0))) {
344 g_warning("socket(AF_INET,SOCK_DGRAM): %m");
347 if (ioctl(sock,FIONBIO,&oneul)) { /* non-blocking mode */
348 g_warning("ioctl(sock,FIONBIO,&1): %m");
349 close(sock); /* errors ignored */
353 udpforward_new(client);
354 client->gpollfd.fd=sock;
355 client->gpollfd.events=SOCK_SOURCE_CHECK_EVENTS;
356 client->gpollfd.revents=0;
357 client->timeout_id=0;
358 sock_client_list=g_list_prepend(sock_client_list,client);
359 g_source_add_poll(sock_gsource,&client->gpollfd);
364 static void client_destroy(struct client *client)
366 g_return_if_fail(client!=NULL);
368 if (!sock_gsource_new())
371 if (client==master) {
373 g_assert(client->timeout_id==0);
376 client_timeout_remove(client);
378 g_source_remove_poll(sock_gsource,&client->gpollfd);
379 sock_client_list=g_list_remove(sock_client_list,client);
380 close(client->gpollfd.fd); /* errors ignored */
384 gboolean network_start(gint port)
387 struct sockaddr_in sockaddr_in;
389 g_return_val_if_fail(port>=0,FALSE);
391 if ((pid_t)-1!=(daemon_pid=is_daemon_running())) {
392 g_warning(_("Cannot start network daemon: Daemon is already running on PID %d"),(int)daemon_pid);
395 g_assert(master==NULL);
396 if (!(master=client_new()))
398 UDPFORWARD_MEMZERO(&sockaddr_in);
399 sockaddr_in.sin_family=AF_INET;
400 sockaddr_in.sin_port=htons(port);
401 sockaddr_in.sin_addr.s_addr=INADDR_ANY;
402 if (bind(master->gpollfd.fd,(struct sockaddr *)&sockaddr_in,sizeof(sockaddr_in))) {
403 g_warning("bind(sock,{AF_INET,INADDR_ANY:%d}): %m",(int)port);
404 sock_gsource_destroy();
407 write_daemon_running(getpid());
411 gboolean network_stop(void)
416 if ((pid_t)-1==(daemon_pid=is_daemon_running())) {
417 g_warning(_("Cannot stop network daemon: Daemon is not running"));
420 if (daemon_pid==getpid()) {
421 sock_gsource_destroy();
425 kill(daemon_pid,SIGKILL);
428 g_warning(udpforward_printf_alloca(_("Unable to stop the daemon at PID %d: %s"),
429 (int)daemon_pid,strerror(errno_save)));