5 * Copyright (C) 2007-2009 Intel Corporation. All rights reserved.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
30 #include <arpa/inet.h>
31 #include <netinet/in.h>
33 #define CONNMAN_API_SUBJECT_TO_CHANGE
34 #include <connman/plugin.h>
35 #include <connman/resolver.h>
36 #include <connman/notifier.h>
37 #include <connman/log.h>
41 #if __BYTE_ORDER == __LITTLE_ENDIAN
56 } __attribute__ ((packed));
57 #elif __BYTE_ORDER == __BIG_ENDIAN
72 } __attribute__ ((packed));
74 #error "Unknown byte order"
87 struct sockaddr_in sin;
99 static GSList *server_list = NULL;
100 static GSList *request_list = NULL;
101 static guint16 request_id = 0x0000;
103 static GIOChannel *listener_channel = NULL;
104 static guint listener_watch = 0;
106 static struct request_data *find_request(guint16 id)
110 for (list = request_list; list; list = list->next) {
111 struct request_data *req = list->data;
113 if (req->dstid == id || req->altid == id)
120 static struct server_data *find_server(const char *interface,
121 const char *domain, const char *server)
125 DBG("interface %s server %s", interface, server);
127 for (list = server_list; list; list = list->next) {
128 struct server_data *data = list->data;
130 if (data->interface == NULL || data->server == NULL)
133 if (g_str_equal(data->interface, interface) == TRUE &&
134 g_str_equal(data->server, server) == TRUE) {
135 if (domain == NULL) {
136 if (data->domain == NULL)
141 if (g_str_equal(data->domain, domain) == TRUE)
149 static gboolean server_event(GIOChannel *channel, GIOCondition condition,
152 struct server_data *data = user_data;
153 struct request_data *req;
154 unsigned char buf[768];
155 struct domain_hdr *hdr = (void *) &buf;
158 if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
159 connman_error("Error with server channel");
164 sk = g_io_channel_unix_get_fd(channel);
166 len = recv(sk, buf, sizeof(buf), 0);
170 DBG("Received %d bytes (id 0x%04x)", len, buf[0] | buf[1] << 8);
172 req = find_request(buf[0] | buf[1] << 8);
176 DBG("id 0x%04x rcode %d", hdr->id, hdr->rcode);
178 buf[0] = req->srcid & 0xff;
179 buf[1] = req->srcid >> 8;
183 if (hdr->rcode == 0 || req->resp == NULL) {
187 req->resp = g_try_malloc(len);
188 if (req->resp == NULL)
191 memcpy(req->resp, buf, len);
195 if (hdr->rcode > 0 && req->numresp < req->numserv)
198 if (req->timeout > 0)
199 g_source_remove(req->timeout);
201 request_list = g_slist_remove(request_list, req);
203 sk = g_io_channel_unix_get_fd(listener_channel);
205 err = sendto(sk, req->resp, req->resplen, 0,
206 (struct sockaddr *) &req->sin, req->len);
214 static struct server_data *create_server(const char *interface,
215 const char *domain, const char *server)
217 struct server_data *data;
218 struct sockaddr_in sin;
221 DBG("interface %s server %s", interface, server);
223 sk = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
225 connman_error("Failed to create server %s socket", server);
229 if (setsockopt(sk, SOL_SOCKET, SO_BINDTODEVICE,
230 interface, strlen(interface) + 1) < 0) {
231 connman_error("Failed to bind server %s to interface %s",
237 memset(&sin, 0, sizeof(sin));
238 sin.sin_family = AF_INET;
239 sin.sin_port = htons(53);
240 sin.sin_addr.s_addr = inet_addr(server);
242 if (connect(sk, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
243 connman_error("Failed to connect server %s", server);
248 data = g_try_new0(struct server_data, 1);
250 connman_error("Failed to allocate server %s data", server);
255 data->channel = g_io_channel_unix_new(sk);
256 if (data->channel == NULL) {
257 connman_error("Failed to create server %s channel", server);
263 g_io_channel_set_close_on_unref(data->channel, TRUE);
265 data->watch = g_io_add_watch(data->channel, G_IO_IN,
268 data->interface = g_strdup(interface);
269 data->domain = g_strdup(domain);
270 data->server = g_strdup(server);
272 /* Enable new servers by default */
273 data->enabled = TRUE;
278 static void destroy_server(struct server_data *data)
280 DBG("interface %s server %s", data->interface, data->server);
283 g_source_remove(data->watch);
285 g_io_channel_unref(data->channel);
287 g_free(data->server);
288 g_free(data->domain);
289 g_free(data->interface);
293 static int dnsproxy_append(const char *interface, const char *domain,
296 struct server_data *data;
298 DBG("interface %s server %s", interface, server);
300 if (g_str_equal(server, "127.0.0.1") == TRUE)
303 data = create_server(interface, domain, server);
307 server_list = g_slist_append(server_list, data);
312 static int dnsproxy_remove(const char *interface, const char *domain,
315 struct server_data *data;
317 DBG("interface %s server %s", interface, server);
319 if (g_str_equal(server, "127.0.0.1") == TRUE)
322 data = find_server(interface, domain, server);
326 server_list = g_slist_remove(server_list, data);
328 destroy_server(data);
333 static struct connman_resolver dnsproxy_resolver = {
335 .priority = CONNMAN_RESOLVER_PRIORITY_HIGH,
336 .append = dnsproxy_append,
337 .remove = dnsproxy_remove,
340 static void dnsproxy_offline_mode(connman_bool_t enabled)
344 DBG("enabled %d", enabled);
346 for (list = server_list; list; list = list->next) {
347 struct server_data *data = list->data;
349 data->enabled = enabled ? FALSE : TRUE;
353 static void dnsproxy_default_changed(struct connman_service *service)
358 DBG("service %p", service);
360 if (service == NULL) {
361 /* When no services are active, then disable DNS proxying */
362 dnsproxy_offline_mode(TRUE);
366 interface = connman_service_get_interface(service);
367 if (interface == NULL)
370 for (list = server_list; list; list = list->next) {
371 struct server_data *data = list->data;
373 if (g_strcmp0(data->interface, interface) == 0)
374 data->enabled = TRUE;
376 data->enabled = FALSE;
382 static struct connman_notifier dnsproxy_notifier = {
384 .default_changed = dnsproxy_default_changed,
385 .offline_mode = dnsproxy_offline_mode,
388 static int parse_request(unsigned char *buf, int len,
389 char *name, unsigned int size)
391 struct domain_hdr *hdr = (void *) buf;
392 uint16_t qdcount = ntohs(hdr->qdcount);
394 char *last_label = NULL;
396 unsigned int remain, used = 0;
401 DBG("id 0x%04x qr %d opcode %d qdcount %d",
402 hdr->id, hdr->qr, hdr->opcode, qdcount);
404 if (hdr->qr != 0 || qdcount != 1)
407 memset(name, 0, size);
417 last_label = (char *) (ptr + 1);
423 if (used + len + 1 > size)
426 strncat(name, (char *) (ptr + 1), len);
435 DBG("query %s (%d labels)", name, label_count);
440 static void send_response(int sk, unsigned char *buf, int len,
441 const struct sockaddr *to, socklen_t tolen)
443 struct domain_hdr *hdr = (void *) buf;
449 DBG("id 0x%04x qr %d opcode %d", hdr->id, hdr->qr, hdr->opcode);
458 err = sendto(sk, buf, len, 0, to, tolen);
461 static int append_query(unsigned char *buf, unsigned int size,
462 const char *query, const char *domain)
464 unsigned char *ptr = buf;
467 DBG("query %s domain %s", query, domain);
469 offset = (char *) query;
470 while (offset != NULL) {
473 tmp = strchr(offset, '.');
475 if (strlen(offset) == 0)
477 *ptr = strlen(offset);
478 memcpy(ptr + 1, offset, strlen(offset));
479 ptr += strlen(offset) + 1;
484 memcpy(ptr + 1, offset, tmp - offset);
485 ptr += tmp - offset + 1;
490 offset = (char *) domain;
491 while (offset != NULL) {
494 tmp = strchr(offset, '.');
496 if (strlen(offset) == 0)
498 *ptr = strlen(offset);
499 memcpy(ptr + 1, offset, strlen(offset));
500 ptr += strlen(offset) + 1;
505 memcpy(ptr + 1, offset, tmp - offset);
506 ptr += tmp - offset + 1;
516 static gboolean request_timeout(gpointer user_data)
518 struct request_data *req = user_data;
520 DBG("id 0x%04x", req->srcid);
522 request_list = g_slist_remove(request_list, req);
524 if (req->resplen > 0 && req->resp != NULL) {
527 sk = g_io_channel_unix_get_fd(listener_channel);
529 err = sendto(sk, req->resp, req->resplen, 0,
530 (struct sockaddr *) &req->sin, req->len);
539 static gboolean listener_event(GIOChannel *channel, GIOCondition condition,
543 unsigned char buf[768];
545 struct request_data *req;
546 struct sockaddr_in sin;
547 socklen_t size = sizeof(sin);
550 if (condition & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
551 connman_error("Error with listener channel");
556 sk = g_io_channel_unix_get_fd(channel);
558 memset(&sin, 0, sizeof(sin));
559 len = recvfrom(sk, buf, sizeof(buf), 0,
560 (struct sockaddr *) &sin, &size);
564 DBG("Received %d bytes (id 0x%04x)", len, buf[0] | buf[1] << 8);
566 err = parse_request(buf, len, query, sizeof(query));
567 if (err < 0 || g_slist_length(server_list) == 0) {
568 send_response(sk, buf, len, (struct sockaddr *) &sin, size);
572 req = g_try_new0(struct request_data, 1);
576 memcpy(&req->sin, &sin, sizeof(sin));
580 if (request_id == 0x0000 || request_id == 0xffff)
583 req->srcid = buf[0] | (buf[1] << 8);
584 req->dstid = request_id;
585 req->altid = request_id + 1;
587 buf[0] = req->dstid & 0xff;
588 buf[1] = req->dstid >> 8;
590 request_list = g_slist_append(request_list, req);
593 req->timeout = g_timeout_add_seconds(5, request_timeout, req);
595 for (list = server_list; list; list = list->next) {
596 struct server_data *data = list->data;
598 DBG("server %s domain %s enabled %d",
599 data->server, data->domain, data->enabled);
601 if (data->enabled == FALSE)
604 sk = g_io_channel_unix_get_fd(data->channel);
606 err = send(sk, buf, len, 0);
610 if (data->domain != NULL) {
611 unsigned char alt[1024];
612 struct domain_hdr *hdr = (void *) &alt;
615 domlen = strlen(data->domain) + 1;
619 alt[0] = req->altid & 0xff;
620 alt[1] = req->altid >> 8;
622 memcpy(alt + 2, buf + 2, 10);
623 hdr->qdcount = htons(1);
625 altlen = append_query(alt + 12, sizeof(alt) - 12,
626 query, data->domain);
632 memcpy(alt + altlen, buf + altlen - domlen,
633 len - altlen + domlen);
635 err = send(sk, alt, altlen + 4, 0);
644 static int create_listener(void)
646 const char *ifname = "lo";
647 struct sockaddr_in sin;
652 sk = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
654 connman_error("Failed to create listener socket");
658 //setsockopt(sk, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt));
659 //setsockopt(sk, SOL_IP, IP_PKTINFO, &opt, sizeof(opt));
661 if (setsockopt(sk, SOL_SOCKET, SO_BINDTODEVICE,
662 ifname, strlen(ifname) + 1) < 0) {
663 connman_error("Failed to bind listener interface");
668 memset(&sin, 0, sizeof(sin));
669 sin.sin_family = AF_INET;
670 sin.sin_port = htons(53);
671 sin.sin_addr.s_addr = inet_addr("127.0.0.1");
672 //sin.sin_addr.s_addr = INADDR_ANY;
674 if (bind(sk, (struct sockaddr *) &sin, sizeof(sin)) < 0) {
675 connman_error("Failed to bind listener socket");
680 listener_channel = g_io_channel_unix_new(sk);
681 if (listener_channel == NULL) {
682 connman_error("Failed to create listener channel");
687 g_io_channel_set_close_on_unref(listener_channel, TRUE);
689 listener_watch = g_io_add_watch(listener_channel, G_IO_IN,
690 listener_event, NULL);
692 connman_resolver_append("lo", NULL, "127.0.0.1");
697 static void destroy_listener(void)
703 connman_resolver_remove_all("lo");
705 if (listener_watch > 0)
706 g_source_remove(listener_watch);
708 for (list = request_list; list; list = list->next) {
709 struct request_data *req = list->data;
711 DBG("Dropping request (id 0x%04x -> 0x%04x)",
712 req->srcid, req->dstid);
719 g_slist_free(request_list);
722 g_io_channel_unref(listener_channel);
725 static int dnsproxy_init(void)
729 err = create_listener();
733 err = connman_resolver_register(&dnsproxy_resolver);
737 err = connman_notifier_register(&dnsproxy_notifier);
744 connman_resolver_unregister(&dnsproxy_resolver);
752 static void dnsproxy_exit(void)
754 connman_notifier_unregister(&dnsproxy_notifier);
756 connman_resolver_unregister(&dnsproxy_resolver);
761 CONNMAN_PLUGIN_DEFINE(dnsproxy, "DNS proxy resolver plugin", VERSION,
762 CONNMAN_PLUGIN_PRIORITY_DEFAULT, dnsproxy_init, dnsproxy_exit)