xref: /freebsd/contrib/wpa/src/wps/wps_er_ssdp.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac)
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 
26 static 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 
131 void 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 
163 int 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 
188 void 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