libeap/src/wps/wps_er_ssdp.c

   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
  20 static 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 += 14;
  82                         pos2 = os_strstr(start, "max-age=");
  83                         if (pos2 == NULL)
  84                                 continue;
  85                         pos2 += 8;
  86                         max_age = atoi(pos2);
  87                 } else if (os_strncasecmp(start, "USN:", 4) == 0) {
  88                         start += 4;
  89                         pos2 = os_strstr(start, "uuid:");
  90                         if (pos2) {
  91                                 pos2 += 5;
  92                                 while (*pos2 == ' ')
  93                                         pos2++;
  94                                 if (uuid_str2bin(pos2, uuid) < 0) {
  95                                         wpa_printf(MSG_DEBUG, "WPS ER: "
  96                                                    "Invalid UUID in USN: %s",
  97                                                    pos2);
  98                                         return;
  99                                 }
 100                         }
 101                 }
 102         }
 103
 104         if (!wfa)
 105                 return; /* Not WPS advertisement/reply */
 106
 107         if (byebye) {
 108                 wps_er_ap_cache_settings(er, &addr.sin_addr);
 109                 wps_er_ap_remove(er, &addr.sin_addr);
 110                 return;
 111         }
 112
 113         if (!location)
 114                 return; /* Unknown location */
 115
 116         if (max_age < 1)
 117                 return; /* No max-age reported */
 118
 119         wpa_printf(MSG_DEBUG, "WPS ER: AP discovered: %s "
 120                    "(packet source: %s  max-age: %d)",
 121                    location, inet_ntoa(addr.sin_addr), max_age);
 122
 123         wps_er_ap_add(er, uuid, &addr.sin_addr, location, max_age);
 124 }
 125
 126
 127 void wps_er_send_ssdp_msearch(struct wps_er *er)
 128 {
 129         struct wpabuf *msg;
 130         struct sockaddr_in dest;
 131
 132         msg = wpabuf_alloc(500);
 133         if (msg == NULL)
 134                 return;
 135
 136         wpabuf_put_str(msg,
 137                        "M-SEARCH * HTTP/1.1\r\n"
 138                        "HOST: 239.255.255.250:1900\r\n"
 139                        "MAN: \"ssdp:discover\"\r\n"
 140                        "MX: 3\r\n"
 141                        "ST: urn:schemas-wifialliance-org:device:WFADevice:1"
 142                        "\r\n"
 143                        "\r\n");
 144
 145         os_memset(&dest, 0, sizeof(dest));
 146         dest.sin_family = AF_INET;
 147         dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
 148         dest.sin_port = htons(UPNP_MULTICAST_PORT);
 149
 150         if (sendto(er->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
 151                    (struct sockaddr *) &dest, sizeof(dest)) < 0)
 152                 wpa_printf(MSG_DEBUG, "WPS ER: M-SEARCH sendto failed: "
 153                            "%d (%s)", errno, strerror(errno));
 154
 155         wpabuf_free(msg);
 156 }
 157
 158
 159 int wps_er_ssdp_init(struct wps_er *er)
 160 {
 161         if (add_ssdp_network(er->ifname)) {
 162                 wpa_printf(MSG_INFO, "WPS ER: Failed to add routing entry for "
 163                            "SSDP");
 164                 return -1;
 165         }
 166
 167         er->multicast_sd = ssdp_open_multicast_sock(er->ip_addr,
 168                                                     er->forced_ifname ?
 169                                                     er->ifname : NULL);
 170         if (er->multicast_sd < 0) {
 171                 wpa_printf(MSG_INFO, "WPS ER: Failed to open multicast socket "
 172                            "for SSDP");
 173                 return -1;
 174         }
 175
 176         er->ssdp_sd = ssdp_listener_open();
 177         if (er->ssdp_sd < 0) {
 178                 wpa_printf(MSG_INFO, "WPS ER: Failed to open SSDP listener "
 179                            "socket");
 180                 return -1;
 181         }
 182
 183         if (eloop_register_sock(er->multicast_sd, EVENT_TYPE_READ,
 184                                 wps_er_ssdp_rx, er, NULL) ||
 185             eloop_register_sock(er->ssdp_sd, EVENT_TYPE_READ,
 186                                 wps_er_ssdp_rx, er, NULL))
 187                 return -1;
 188
 189         wps_er_send_ssdp_msearch(er);
 190
 191         return 0;
 192 }
 193
 194
 195 void wps_er_ssdp_deinit(struct wps_er *er)
 196 {
 197         if (er->multicast_sd >= 0) {
 198                 eloop_unregister_sock(er->multicast_sd, EVENT_TYPE_READ);
 199                 close(er->multicast_sd);
 200         }
 201         if (er->ssdp_sd >= 0) {
 202                 eloop_unregister_sock(er->ssdp_sd, EVENT_TYPE_READ);
 203                 close(er->ssdp_sd);
 204         }
 205 }