aboutsummaryrefslogtreecommitdiffstats
path: root/src/listen.c
blob: fe728be439e858ec592e0737998335b2bc2bd1a7 (plain) (blame)
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
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
/* the Music Player Daemon (MPD)
 * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
 * This project's homepage is: http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "listen.h"
#include "client.h"
#include "conf.h"
#include "utils.h"
#include "config.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>

#ifdef WIN32
#include <ws2tcpip.h>
#include <winsock.h>
#else
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netdb.h>
#endif

#undef G_LOG_DOMAIN
#define G_LOG_DOMAIN "listen"

#define MAXHOSTNAME 	1024

#define ALLOW_REUSE	1

#define DEFAULT_PORT	6600

#define BINDERROR() do { \
	g_error("unable to bind port %u: %s; " \
		"maybe MPD is still running?", \
		port, strerror(errno)); \
} while (0);

struct listen_socket {
	struct listen_socket *next;

	int fd;

	guint source_id;
};

static struct listen_socket *listen_sockets;
int boundPort;

static gboolean
listen_in_event(GIOChannel *source, GIOCondition condition, gpointer data);

static int establishListen(int pf, const struct sockaddr *addrp,
			   socklen_t addrlen)
{
	int sock;
	int allowReuse = ALLOW_REUSE;
#ifdef HAVE_STRUCT_UCRED
	int passcred = 1;
#endif
	struct listen_socket *ls;
	GIOChannel *channel;

	if ((sock = socket(pf, SOCK_STREAM, 0)) < 0)
		g_error("socket < 0");

	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&allowReuse,
		       sizeof(allowReuse)) < 0) {
		g_error("problems setsockopt'ing: %s", strerror(errno));
	}

	if (bind(sock, addrp, addrlen) < 0) {
		close(sock);
		return -1;
	}

	if (listen(sock, 5) < 0)
		g_error("problems listen'ing: %s", strerror(errno));

#ifdef HAVE_STRUCT_UCRED
	setsockopt(sock, SOL_SOCKET, SO_PASSCRED, &passcred, sizeof(passcred));
#endif

	ls = g_new(struct listen_socket, 1);
	ls->fd = sock;

	channel = g_io_channel_unix_new(sock);
	ls->source_id = g_io_add_watch(channel, G_IO_IN,
				       listen_in_event, GINT_TO_POINTER(sock));
	g_io_channel_unref(channel);

	ls->next = listen_sockets;
	listen_sockets = ls;

	return 0;
}

#ifdef HAVE_IPV6
static bool ipv6Supported(void)
{
	int s;
	s = socket(AF_INET6, SOCK_STREAM, 0);
	if (s == -1)
		return false;
	close(s);
	return true;
}
#endif

static void
parseListenConfigParam(G_GNUC_UNUSED unsigned int port, ConfigParam * param)
{
	const struct sockaddr *addrp;
	socklen_t addrlen;
#ifdef HAVE_TCP
	struct sockaddr_in sin4;
#ifdef HAVE_IPV6
	struct sockaddr_in6 sin6;
	int useIpv6 = ipv6Supported();

	memset(&sin6, 0, sizeof(struct sockaddr_in6));
	sin6.sin6_port = htons(port);
	sin6.sin6_family = AF_INET6;
#endif
	memset(&sin4, 0, sizeof(struct sockaddr_in));
	sin4.sin_port = htons(port);
	sin4.sin_family = AF_INET;
#endif /* HAVE_TCP */

	if (!param || 0 == strcmp(param->value, "any")) {
#ifdef HAVE_TCP
		g_debug("binding to any address");
#ifdef HAVE_IPV6
		if (useIpv6) {
			sin6.sin6_addr = in6addr_any;
			addrp = (const struct sockaddr *)&sin6;
			addrlen = sizeof(struct sockaddr_in6);
			if (establishListen(PF_INET6, addrp, addrlen) < 0)
				BINDERROR();
		}
#endif
		sin4.sin_addr.s_addr = INADDR_ANY;
		addrp = (const struct sockaddr *)&sin4;
		addrlen = sizeof(struct sockaddr_in);
#ifdef HAVE_IPV6
		if ((establishListen(PF_INET, addrp, addrlen) < 0) && !useIpv6) {
#else
		if (establishListen(PF_INET, addrp, addrlen) < 0) {
#endif
			BINDERROR();
		}
#else /* HAVE_TCP */
		g_error("TCP support is disabled");
#endif /* HAVE_TCP */
#ifdef HAVE_UN
	} else if (param->value[0] == '/') {
		size_t path_length;
		struct sockaddr_un s_un;

		path_length = strlen(param->value);
		if (path_length >= sizeof(s_un.sun_path))
			g_error("unix socket path is too long");

		unlink(param->value);

		s_un.sun_family = AF_UNIX;
		memcpy(s_un.sun_path, param->value, path_length + 1);

		addrp = (const struct sockaddr *)&s_un;
		addrlen = sizeof(s_un);

		if (establishListen(PF_UNIX, addrp, addrlen) < 0)
			g_error("unable to bind to %s: %s",
				param->value, strerror(errno));

		/* allow everybody to connect */
		chmod(param->value, 0666);

#endif /* HAVE_UN */
	} else {
#ifdef HAVE_TCP
#ifndef WIN32
		struct addrinfo hints, *ai, *i;
		char service[20];
		int ret;

		g_debug("binding to address for %s", param->value);

		memset(&hints, 0, sizeof(hints));
		hints.ai_flags = AI_PASSIVE;
#ifdef AI_ADDRCONFIG
		hints.ai_flags |= AI_ADDRCONFIG;
#endif
		hints.ai_family = PF_UNSPEC;
		hints.ai_socktype = SOCK_STREAM;
		hints.ai_protocol = IPPROTO_TCP;

		g_snprintf(service, sizeof(service), "%u", port);

		ret = getaddrinfo(param->value, service, &hints, &ai);
		if (ret != 0)
			g_error("can't lookup host \"%s\" at line %i: %s",
				param->value, param->line, gai_strerror(ret));

		for (i = ai; i != NULL; i = i->ai_next)
			if (establishListen(i->ai_family, i->ai_addr,
					    i->ai_addrlen) < 0)
				BINDERROR();

		freeaddrinfo(ai);
#else /* WIN32 */
		const struct hostent *he;

		g_debug("binding to address for %s", param->value);

		he = gethostbyname(param->value);
		if (he == NULL)
			g_error("can't lookup host \"%s\" at line %i",
				param->value, param->line);

		if (he->h_addrtype != AF_INET)
			g_error("IPv4 address expected for host \"%s\" at line %i",
				param->value, param->line);

		if (establishListen(AF_INET, he->h_addr, he->h_length) < 0)
			BINDERROR();
#endif /* !WIN32 */
#else /* HAVE_TCP */
		g_error("TCP support is disabled");
#endif /* HAVE_TCP */
	}
}

void listenOnPort(void)
{
	int port = DEFAULT_PORT;
	ConfigParam *param = getNextConfigParam(CONF_BIND_TO_ADDRESS, NULL);
	ConfigParam *portParam = getConfigParam(CONF_PORT);

	if (portParam) {
		char *test;
		port = strtol(portParam->value, &test, 10);
		if (port <= 0 || *test != '\0') {
			g_error("%s \"%s\" specified at line %i is not a "
				"positive integer",
				CONF_PORT,
				portParam->value, portParam->line);
		}
	}

	boundPort = port;

	do {
		parseListenConfigParam(port, param);
	} while ((param = getNextConfigParam(CONF_BIND_TO_ADDRESS, param)));
}

void closeAllListenSockets(void)
{
	g_debug("closeAllListenSockets called");

	while (listen_sockets != NULL) {
		struct listen_socket *ls = listen_sockets;
		listen_sockets = ls->next;

		g_source_remove(ls->source_id);
		close(ls->fd);
		g_free(ls);
	}
}

static int get_remote_uid(int fd)
{
#ifdef HAVE_STRUCT_UCRED
	struct ucred cred;
	socklen_t len = sizeof (cred);

	if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &cred, &len) < 0)
		return 0;

	return cred.uid;
#else
	(void)fd;
	return -1;
#endif
}

static gboolean
listen_in_event(G_GNUC_UNUSED GIOChannel *source,
		G_GNUC_UNUSED GIOCondition condition,
		gpointer data)
{
	int listen_fd = GPOINTER_TO_INT(data), fd;
	struct sockaddr sockAddr;
	socklen_t socklen = sizeof(sockAddr);

	fd = accept(listen_fd, &sockAddr, &socklen);
	if (fd >= 0) {
		set_nonblocking(fd);

		client_new(fd, &sockAddr, get_remote_uid(fd));
	} else if (fd < 0 && errno != EINTR) {
		g_warning("Problems accept()'ing");
	}

	return true;
}