aboutsummaryrefslogtreecommitdiffstats
path: root/apps/app_zapras.c
blob: de682f72c44d7ac03a7dbdfe46c64f243e6c4e2f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Execute an ISDN RAS
 *
 * \author Mark Spencer <markster@digium.com>
 * 
 * \ingroup applications
 */

/*** MODULEINFO
	<depend>zaptel</depend>
 ***/

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include <sys/ioctl.h>
#include <sys/wait.h>
#ifdef __linux__
#include <sys/signal.h>
#else
#include <signal.h>
#endif /* __linux__ */

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <stdio.h>
#include <fcntl.h>
#include <zaptel/zaptel.h>

#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/module.h"
#include "asterisk/options.h"

static char *app = "ZapRAS";

static char *synopsis = "Executes Zaptel ISDN RAS application";

static char *descrip =
"  ZapRAS(args): Executes a RAS server using pppd on the given channel.\n"
"The channel must be a clear channel (i.e. PRI source) and a Zaptel\n"
"channel to be able to use this function (No modem emulation is included).\n"
"Your pppd must be patched to be zaptel aware. Arguments should be\n"
"separated by | characters.\n";


#define PPP_MAX_ARGS	32
#define PPP_EXEC	"/usr/sbin/pppd"

static pid_t spawn_ras(struct ast_channel *chan, char *args)
{
	pid_t pid;
	int x;	
	char *c;

	char *argv[PPP_MAX_ARGS];
	int argc = 0;
	char *stringp=NULL;

	/* Start by forking */
	pid = fork();
	if (pid)
		return pid;

	/* Execute RAS on File handles */
	dup2(chan->fds[0], STDIN_FILENO);

	/* Drop high priority */
	if (ast_opt_high_priority)
		ast_set_priority(0);

	/* Close other file descriptors */
	for (x=STDERR_FILENO + 1;x<1024;x++) 
		close(x);

	/* Restore original signal handlers */
	for (x=0;x<NSIG;x++)
		signal(x, SIG_DFL);

	/* Reset all arguments */
	memset(argv, 0, sizeof(argv));

	/* First argument is executable, followed by standard
	   arguments for zaptel PPP */
	argv[argc++] = PPP_EXEC;
	argv[argc++] = "nodetach";

	/* And all the other arguments */
	stringp=args;
	c = strsep(&stringp, "|");
	while(c && strlen(c) && (argc < (PPP_MAX_ARGS - 4))) {
		argv[argc++] = c;
		c = strsep(&stringp, "|");
	}

	argv[argc++] = "plugin";
	argv[argc++] = "zaptel.so";
	argv[argc++] = "stdin";

	/* Finally launch PPP */
	execv(PPP_EXEC, argv);
	fprintf(stderr, "Failed to exec PPPD!\n");
	exit(1);
}

static void run_ras(struct ast_channel *chan, char *args)
{
	pid_t pid;
	int status;
	int res;
	int signalled = 0;
	struct zt_bufferinfo savebi;
	int x;
	
	res = ioctl(chan->fds[0], ZT_GET_BUFINFO, &savebi);
	if(res) {
		ast_log(LOG_WARNING, "Unable to check buffer policy on channel %s\n", chan->name);
		return;
	}

	pid = spawn_ras(chan, args);
	if (pid < 0) {
		ast_log(LOG_WARNING, "Failed to spawn RAS\n");
	} else {
		for (;;) {
			res = wait4(pid, &status, WNOHANG, NULL);
			if (!res) {
				/* Check for hangup */
				if (chan->_softhangup && !signalled) {
					ast_log(LOG_DEBUG, "Channel '%s' hungup.  Signalling RAS at %d to die...\n", chan->name, pid);
					kill(pid, SIGTERM);
					signalled=1;
				}
				/* Try again */
				sleep(1);
				continue;
			}
			if (res < 0) {
				ast_log(LOG_WARNING, "wait4 returned %d: %s\n", res, strerror(errno));
			}
			if (option_verbose > 2) {
				if (WIFEXITED(status)) {
					ast_verbose(VERBOSE_PREFIX_3 "RAS on %s terminated with status %d\n", chan->name, WEXITSTATUS(status));
				} else if (WIFSIGNALED(status)) {
					ast_verbose(VERBOSE_PREFIX_3 "RAS on %s terminated with signal %d\n", 
						 chan->name, WTERMSIG(status));
				} else {
					ast_verbose(VERBOSE_PREFIX_3 "RAS on %s terminated weirdly.\n", chan->name);
				}
			}
			/* Throw back into audio mode */
			x = 1;
			ioctl(chan->fds[0], ZT_AUDIOMODE, &x);

			/* Restore saved values */
			res = ioctl(chan->fds[0], ZT_SET_BUFINFO, &savebi);
			if (res < 0) {
				ast_log(LOG_WARNING, "Unable to set buffer policy on channel %s\n", chan->name);
			}
			break;
		}
	}
}

static int zapras_exec(struct ast_channel *chan, void *data)
{
	int res=-1;
	char *args;
	struct ast_module_user *u;
	ZT_PARAMS ztp;

	if (!data) 
		data = "";

	u = ast_module_user_add(chan);

	args = ast_strdupa(data);
	
	/* Answer the channel if it's not up */
	if (chan->_state != AST_STATE_UP)
		ast_answer(chan);
	if (strcasecmp(chan->tech->type, "Zap")) {
		/* If it's not a zap channel, we're done.  Wait a couple of
		   seconds and then hangup... */
		if (option_verbose > 1)
			ast_verbose(VERBOSE_PREFIX_2 "Channel %s is not a Zap channel\n", chan->name);
		sleep(2);
	} else {
		memset(&ztp, 0, sizeof(ztp));
		if (ioctl(chan->fds[0], ZT_GET_PARAMS, &ztp)) {
			ast_log(LOG_WARNING, "Unable to get zaptel parameters\n");
		} else if (ztp.sigtype != ZT_SIG_CLEAR) {
			if (option_verbose > 1)
				ast_verbose(VERBOSE_PREFIX_2 "Channel %s is not a clear channel\n", chan->name);
		} else {
			/* Everything should be okay.  Run PPP. */
			if (option_verbose > 2)
				ast_verbose(VERBOSE_PREFIX_3 "Starting RAS on %s\n", chan->name);
			/* Execute RAS */
			run_ras(chan, args);
		}
	}
	ast_module_user_remove(u);
	return res;
}

static int unload_module(void) 
{
	int res;

	res = ast_unregister_application(app);
	
	ast_module_user_hangup_all();

	return res;
}

static int load_module(void)
{
	return ast_register_application(app, zapras_exec, synopsis, descrip);
}

AST_MODULE_INFO_STANDARD(ASTERISK_GPL_KEY, "Zap RAS Application");