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