1/*
2 * Wi-Fi Protected Setup - External Registrar (SSDP)
3 * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
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 version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "uuid.h"
19#include "eloop.h"
20#include "wps_i.h"
21#include "wps_upnp.h"
22#include "wps_upnp_i.h"
23#include "wps_er.h"
24
25
26static void wps_er_ssdp_rx(int sd, void *eloop_ctx, void *sock_ctx)
27{
28	struct wps_er *er = eloop_ctx;
29	struct sockaddr_in addr; /* client address */
30	socklen_t addr_len;
31	int nread;
32	char buf[MULTICAST_MAX_READ], *pos, *pos2, *start;
33	int wfa = 0, byebye = 0;
34	int max_age = -1;
35	char *location = NULL;
36	u8 uuid[WPS_UUID_LEN];
37
38	addr_len = sizeof(addr);
39	nread = recvfrom(sd, buf, sizeof(buf) - 1, 0,
40			 (struct sockaddr *) &addr, &addr_len);
41	if (nread <= 0)
42		return;
43	buf[nread] = '\0';
44	if (er->filter_addr.s_addr &&
45	    er->filter_addr.s_addr != addr.sin_addr.s_addr)
46		return;
47
48	wpa_printf(MSG_DEBUG, "WPS ER: Received SSDP from %s",
49		   inet_ntoa(addr.sin_addr));
50	wpa_hexdump_ascii(MSG_MSGDUMP, "WPS ER: Received SSDP contents",
51			  (u8 *) buf, nread);
52
53	if (sd == er->multicast_sd) {
54		/* Reply to M-SEARCH */
55		if (os_strncmp(buf, "HTTP/1.1 200 OK", 15) != 0)
56			return; /* unexpected response header */
57	} else {
58		/* Unsolicited message (likely NOTIFY or M-SEARCH) */
59		if (os_strncmp(buf, "NOTIFY ", 7) != 0)
60			return; /* only process notifications */
61	}
62
63	os_memset(uuid, 0, sizeof(uuid));
64
65	for (start = buf; start && *start; start = pos) {
66		pos = os_strchr(start, '\n');
67		if (pos) {
68			if (pos[-1] == '\r')
69				pos[-1] = '\0';
70			*pos++ = '\0';
71		}
72		if (os_strstr(start, "schemas-wifialliance-org:device:"
73			      "WFADevice:1"))
74			wfa = 1;
75		if (os_strstr(start, "schemas-wifialliance-org:service:"
76			      "WFAWLANConfig:1"))
77			wfa = 1;
78		if (os_strncasecmp(start, "LOCATION:", 9) == 0) {
79			start += 9;
80			while (*start == ' ')
81				start++;
82			location = start;
83		} else if (os_strncasecmp(start, "NTS:", 4) == 0) {
84			if (os_strstr(start, "ssdp:byebye"))
85				byebye = 1;
86		} else if (os_strncasecmp(start, "CACHE-CONTROL:", 14) == 0) {
87			start += 9;
88			while (*start == ' ')
89				start++;
90			pos2 = os_strstr(start, "max-age=");
91			if (pos2 == NULL)
92				continue;
93			pos2 += 8;
94			max_age = atoi(pos2);
95		} else if (os_strncasecmp(start, "USN:", 4) == 0) {
96			start += 4;
97			pos2 = os_strstr(start, "uuid:");
98			if (pos2) {
99				pos2 += 5;
100				while (*pos2 == ' ')
101					pos2++;
102				if (uuid_str2bin(pos2, uuid) < 0) {
103					wpa_printf(MSG_DEBUG, "WPS ER: "
104						   "Invalid UUID in USN: %s",
105						   pos2);
106					return;
107				}
108			}
109		}
110	}
111
112	if (!wfa)
113		return; /* Not WPS advertisement/reply */
114
115	if (byebye) {
116		wps_er_ap_cache_settings(er, &addr.sin_addr);
117		wps_er_ap_remove(er, &addr.sin_addr);
118		return;
119	}
120
121	if (!location)
122		return; /* Unknown location */
123
124	if (max_age < 1)
125		return; /* No max-age reported */
126
127	wpa_printf(MSG_DEBUG, "WPS ER: AP discovered: %s "
128		   "(packet source: %s  max-age: %d)",
129		   location, inet_ntoa(addr.sin_addr), max_age);
130
131	wps_er_ap_add(er, uuid, &addr.sin_addr, location, max_age);
132}
133
134
135void wps_er_send_ssdp_msearch(struct wps_er *er)
136{
137	struct wpabuf *msg;
138	struct sockaddr_in dest;
139
140	msg = wpabuf_alloc(500);
141	if (msg == NULL)
142		return;
143
144	wpabuf_put_str(msg,
145		       "M-SEARCH * HTTP/1.1\r\n"
146		       "HOST: 239.255.255.250:1900\r\n"
147		       "MAN: \"ssdp:discover\"\r\n"
148		       "MX: 3\r\n"
149		       "ST: urn:schemas-wifialliance-org:device:WFADevice:1"
150		       "\r\n"
151		       "\r\n");
152
153	os_memset(&dest, 0, sizeof(dest));
154	dest.sin_family = AF_INET;
155	dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
156	dest.sin_port = htons(UPNP_MULTICAST_PORT);
157
158	if (sendto(er->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
159		   (struct sockaddr *) &dest, sizeof(dest)) < 0)
160		wpa_printf(MSG_DEBUG, "WPS ER: M-SEARCH sendto failed: "
161			   "%d (%s)", errno, strerror(errno));
162
163	wpabuf_free(msg);
164}
165
166
167int wps_er_ssdp_init(struct wps_er *er)
168{
169	if (add_ssdp_network(er->ifname)) {
170		wpa_printf(MSG_INFO, "WPS ER: Failed to add routing entry for "
171			   "SSDP");
172		return -1;
173	}
174
175	er->multicast_sd = ssdp_open_multicast_sock(er->ip_addr);
176	if (er->multicast_sd < 0) {
177		wpa_printf(MSG_INFO, "WPS ER: Failed to open multicast socket "
178			   "for SSDP");
179		return -1;
180	}
181
182	er->ssdp_sd = ssdp_listener_open();
183	if (er->ssdp_sd < 0) {
184		wpa_printf(MSG_INFO, "WPS ER: Failed to open SSDP listener "
185			   "socket");
186		return -1;
187	}
188
189	if (eloop_register_sock(er->multicast_sd, EVENT_TYPE_READ,
190				wps_er_ssdp_rx, er, NULL) ||
191	    eloop_register_sock(er->ssdp_sd, EVENT_TYPE_READ,
192				wps_er_ssdp_rx, er, NULL))
193		return -1;
194
195	wps_er_send_ssdp_msearch(er);
196
197	return 0;
198}
199
200
201void wps_er_ssdp_deinit(struct wps_er *er)
202{
203	if (er->multicast_sd >= 0) {
204		eloop_unregister_sock(er->multicast_sd, EVENT_TYPE_READ);
205		close(er->multicast_sd);
206	}
207	if (er->ssdp_sd >= 0) {
208		eloop_unregister_sock(er->ssdp_sd, EVENT_TYPE_READ);
209		close(er->ssdp_sd);
210	}
211}
212