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 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                                 uuid_str2bin(pos2, uuid);
 100                         }
 101                 }
 102         }
 103
 104         if (!wfa)
 105                 return; /* Not WPS advertisement/reply */
 106
 107         if (byebye) {
 108                 wps_er_ap_remove(er, &addr.sin_addr);
 109                 return;
 110         }
 111
 112         if (!location)
 113                 return; /* Unknown location */
 114
 115         if (max_age < 1)
 116                 return; /* No max-age reported */
 117
 118         wpa_printf(MSG_DEBUG, "WPS ER: AP discovered: %s "
 119                    "(packet source: %s  max-age: %d)",
 120                    location, inet_ntoa(addr.sin_addr), max_age);
 121
 122         wps_er_ap_add(er, uuid, &addr.sin_addr, location, max_age);
 123 }
 124
 125
 126 void wps_er_send_ssdp_msearch(struct wps_er *er)
 127 {
 128         struct wpabuf *msg;
 129         struct sockaddr_in dest;
 130
 131         msg = wpabuf_alloc(500);
 132         if (msg == NULL)
 133                 return;
 134
 135         wpabuf_put_str(msg,
 136                        "M-SEARCH * HTTP/1.1\r\n"
 137                        "HOST: 239.255.255.250:1900\r\n"
 138                        "MAN: \"ssdp:discover\"\r\n"
 139                        "MX: 3\r\n"
 140                        "ST: urn:schemas-wifialliance-org:device:WFADevice:1"
 141                        "\r\n"
 142                        "\r\n");
 143
 144         os_memset(&dest, 0, sizeof(dest));
 145         dest.sin_family = AF_INET;
 146         dest.sin_addr.s_addr = inet_addr(UPNP_MULTICAST_ADDRESS);
 147         dest.sin_port = htons(UPNP_MULTICAST_PORT);
 148
 149         if (sendto(er->multicast_sd, wpabuf_head(msg), wpabuf_len(msg), 0,
 150                    (struct sockaddr *) &dest, sizeof(dest)) < 0)
 151                 wpa_printf(MSG_DEBUG, "WPS ER: M-SEARCH sendto failed: "
 152                            "%d (%s)", errno, strerror(errno));
 153
 154         wpabuf_free(msg);
 155 }
 156
 157
 158 int wps_er_ssdp_init(struct wps_er *er)
 159 {
 160         if (add_ssdp_network(er->ifname))
 161                 return -1;
 162
 163         er->multicast_sd = ssdp_open_multicast_sock(er->ip_addr);
 164         if (er->multicast_sd < 0)
 165                 return -1;
 166
 167         er->ssdp_sd = ssdp_listener_open();
 168         if (er->ssdp_sd < 0)
 169                 return -1;
 170
 171         if (eloop_register_sock(er->multicast_sd, EVENT_TYPE_READ,
 172                                 wps_er_ssdp_rx, er, NULL) ||
 173             eloop_register_sock(er->ssdp_sd, EVENT_TYPE_READ,
 174                                 wps_er_ssdp_rx, er, NULL))
 175                 return -1;
 176
 177         wps_er_send_ssdp_msearch(er);
 178
 179         return 0;
 180 }
 181
 182
 183 void wps_er_ssdp_deinit(struct wps_er *er)
 184 {
 185         if (er->multicast_sd >= 0) {
 186                 eloop_unregister_sock(er->multicast_sd, EVENT_TYPE_READ);
 187                 close(er->multicast_sd);
 188         }
 189         if (er->ssdp_sd >= 0) {
 190                 eloop_unregister_sock(er->ssdp_sd, EVENT_TYPE_READ);
 191                 close(er->ssdp_sd);
 192         }
 193 }