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
45	wpa_printf(MSG_DEBUG, "WPS ER: Received SSDP from %s",
46		   inet_ntoa(addr.sin_addr));
47	wpa_hexdump_ascii(MSG_MSGDUMP, "WPS ER: Received SSDP contents",
48			  (u8 *) buf, nread);
49
50	if (sd == er->multicast_sd) {
51		/* Reply to M-SEARCH */
52		if (os_strncmp(buf, "HTTP/1.1 200 OK", 15) != 0)
53			return; /* unexpected response header */
54	} else {
55		/* Unsolicited message (likely NOTIFY or M-SEARCH) */
56		if (os_strncmp(buf, "NOTIFY ", 7) != 0)
57			return; /* only process notifications */
58	}
59
60	os_memset(uuid, 0, sizeof(uuid));
61
62	for (start = buf; start && *start; start = pos) {
63		pos = os_strchr(start, '\n');
64		if (pos) {
65			if (pos[-1] == '\r')
66				pos[-1] = '\0';
67			*pos++ = '\0';
68		}
69		if (os_strstr(start, "schemas-wifialliance-org:device:"
70			      "WFADevice:1"))
71			wfa = 1;
72		if (os_strstr(start, "schemas-wifialliance-org:service:"
73			      "WFAWLANConfig:1"))
74			wfa = 1;
75		if (os_strncasecmp(start, "LOCATION:", 9) == 0) {
76			start += 9;
77			while (*start == ' ')
78				start++;
79			location = start;
80		} else if (os_strncasecmp(start, "NTS:", 4) == 0) {
81			if (os_strstr(start, "ssdp:byebye"))
82				byebye = 1;
83		} else if (os_strncasecmp(start, "CACHE-CONTROL:", 14) == 0) {
84			start += 9;
85			while (*start == ' ')
86				start++;
87			pos2 = os_strstr(start, "max-age=");
88			if (pos2 == NULL)
89				continue;
90			pos2 += 8;
91			max_age = atoi(pos2);
92		} else if (os_strncasecmp(start, "USN:", 4) == 0) {
93			start += 4;
94			pos2 = os_strstr(start, "uuid:");
95			if (pos2) {
96				pos2 += 5;
97				while (*pos2 == ' ')
98					pos2++;
99				if (uuid_str2bin(pos2, uuid) < 0) {
100					wpa_printf(MSG_DEBUG, "WPS ER: "
101						   "Invalid UUID in USN: %s",
102						   pos2);
103					return;
104				}
105			}
106		}
107	}
108
109	if (!wfa)
110		return; /* Not WPS advertisement/reply */
111
112	if (byebye) {
113		wps_er_ap_remove(er, &addr.sin_addr);
114		return;
115	}
116
117	if (!location)
118		return; /* Unknown location */
119
120	if (max_age < 1)
121		return; /* No max-age reported */
122
123	wpa_printf(MSG_DEBUG, "WPS ER: AP discovered: %s "
124		   "(packet source: %s  max-age: %d)",
125		   location, inet_ntoa(addr.sin_addr), max_age);
126
127	wps_er_ap_add(er, uuid, &addr.sin_addr, location, max_age);
128}
129
130
131void wps_er_send_ssdp_msearch(struct wps_er *er)
132{
133	struct wpabuf *msg;
134	struct sockaddr_in dest;
135
136	msg = wpabuf_alloc(500);
137	if (msg == NULL)
138		return;
139
140	wpabuf_put_str(msg,
141		       "M-SEARCH * HTTP/1.1\r\n"
142		       "HOST: 239.255.255.250:1900\r\n"
143		       "MAN: \"ssdp:discover\"\r\n"
144		       "MX: 3\r\n"
145		       "ST: urn:schemas-wifialliance-org:device:WFADevice:1"
146		       "\r\n"
147		       "\r\n");
148
149	os_memset(&dest, 0, sizeof(dest));
150	dest.sin_family = AF_INET;
151	dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
152	dest.sin_port = htons(UPNP_MULTICAST_PORT);
153
154	if (sendto(er->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
155		   (struct sockaddr *) &dest, sizeof(dest)) < 0)
156		wpa_printf(MSG_DEBUG, "WPS ER: M-SEARCH sendto failed: "
157			   "%d (%s)", errno, strerror(errno));
158
159	wpabuf_free(msg);
160}
161
162
163int wps_er_ssdp_init(struct wps_er *er)
164{
165	if (add_ssdp_network(er->ifname))
166		return -1;
167
168	er->multicast_sd = ssdp_open_multicast_sock(er->ip_addr);
169	if (er->multicast_sd < 0)
170		return -1;
171
172	er->ssdp_sd = ssdp_listener_open();
173	if (er->ssdp_sd < 0)
174		return -1;
175
176	if (eloop_register_sock(er->multicast_sd, EVENT_TYPE_READ,
177				wps_er_ssdp_rx, er, NULL) ||
178	    eloop_register_sock(er->ssdp_sd, EVENT_TYPE_READ,
179				wps_er_ssdp_rx, er, NULL))
180		return -1;
181
182	wps_er_send_ssdp_msearch(er);
183
184	return 0;
185}
186
187
188void wps_er_ssdp_deinit(struct wps_er *er)
189{
190	if (er->multicast_sd >= 0) {
191		eloop_unregister_sock(er->multicast_sd, EVENT_TYPE_READ);
192		close(er->multicast_sd);
193	}
194	if (er->ssdp_sd >= 0) {
195		eloop_unregister_sock(er->ssdp_sd, EVENT_TYPE_READ);
196		close(er->ssdp_sd);
197	}
198}
199