carl9170fw/carlfw/src/wol.c

   1 /*
   2  * carl9170 firmware - used by the ar9170 wireless device
   3  *
   4  * WakeUp on WLAN functions
   5  *
   6  * Copyright 2011       Christian Lamparter <chunkeey@googlemail.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include "carl9170.h"
  23 #include "shared/phy.h"
  24 #include "timer.h"
  25 #include "wl.h"
  26 #include "printf.h"
  27 #include "rf.h"
  28 #include "wol.h"
  29 #include "linux/ieee80211.h"
  30
  31 #ifdef CONFIG_CARL9170FW_WOL
  32
  33 void wol_cmd(const struct carl9170_wol_cmd *cmd)
  34 {
  35         memcpy(&fw.wol.cmd, cmd, sizeof(cmd));
  36 }
  37
  38 void wol_prepare(void)
  39 {
  40         /* set MAC filter */
  41         memcpy((void *)AR9170_MAC_REG_MAC_ADDR_L, fw.wol.cmd.mac, 6);
  42         memcpy((void *)AR9170_MAC_REG_BSSID_L, fw.wol.cmd.bssid, 6);
  43         set(AR9170_MAC_REG_RX_CONTROL, AR9170_MAC_RX_CTRL_DEAGG);
  44
  45         /* set filter policy to: discard everything */
  46         fw.wlan.rx_filter = CARL9170_RX_FILTER_EVERYTHING;
  47
  48         /* reenable rx dma */
  49         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
  50
  51         /* initialize the last_beacon timer */
  52         fw.wol.last_null = fw.wol.last_beacon = get_clock_counter();
  53 }
  54
  55 #ifdef CONFIG_CARL9170FW_WOL_NL80211_TRIGGERS
  56 static bool wlan_rx_wol_magic_packet(const struct ieee80211_hdr *hdr, const unsigned int len)
  57 {
  58         const unsigned char *data, *end, *mac;
  59         unsigned int found = 0;
  60
  61         /*
  62          * LIMITATION:
  63          * We can only scan the first AR9170_BLOCK_SIZE [=~320] bytes
  64          * for MAGIC patterns!
  65          */
  66
  67         mac = (const unsigned char *) AR9170_MAC_REG_MAC_ADDR_L;
  68
  69         data = (u8 *)((unsigned long)hdr + ieee80211_hdrlen(hdr->frame_control));
  70         end = (u8 *)((unsigned long)hdr + len);
  71
  72         /*
  73          * scan for standard WOL Magic frame
  74          *
  75          * "A physical WakeOnLAN (Magic Packet) will look like this:
  76          * ---------------------------------------------------------------
  77          * | Synchronization Stream | Target MAC |  Password (optional)  |
  78          * |    6 octets            | 96 octets  |   0, 4 or 6           |
  79          * ---------------------------------------------------------------
  80          *
  81          * The Synchronization Stream is defined as 6 bytes of FFh.
  82          * The Target MAC block contains 16 duplications of the IEEEaddress
  83          * of the target, with no breaks or interruptions.
  84          *
  85          * The Password field is optional, but if present, contains either
  86          * 4 bytes or 6 bytes. The WakeOnLAN dissector was implemented to
  87          * dissect the password, if present, according to the command-line
  88          * format that ether-wake uses, therefore, if a 4-byte password is
  89          * present, it will be dissected as an IPv4 address and if a 6-byte
  90          * password is present, it will be dissected as an Ethernet address.
  91          *
  92          * <http://wiki.wireshark.org/WakeOnLAN>
  93          */
  94
  95         while (data < end) {
  96                 if (found >= 6) {
  97                         if (*data == mac[found % 6])
  98                                 found++;
  99                         else
 100                                 found = 0;
 101                 }
 102
 103                 /* previous check might reset found counter */
 104                 if (found < 6) {
 105                         if (*data == 0xff)
 106                                 found++;
 107                         else
 108                                 found = 0;
 109                 }
 110
 111                 if (found == (6 + 16 * 6))
 112                         return true;
 113
 114                 data++;
 115         }
 116
 117         return false;
 118 }
 119
 120 static void wlan_wol_connect_callback(void __unused *dummy, bool success)
 121 {
 122         if (success)
 123                 fw.wol.lost_null = 0;
 124         else
 125                 fw.wol.lost_null++;
 126 }
 127
 128 static void wlan_wol_connection_monitor(void)
 129 {
 130         struct carl9170_tx_null_superframe *nullf = &dma_mem.reserved.cmd.null;
 131         struct ieee80211_hdr *null = (struct ieee80211_hdr *) &nullf->f.null;
 132
 133         if (!fw.wlan.fw_desc_available)
 134                 return;
 135
 136         memset(nullf, 0, sizeof(*nullf));
 137
 138         nullf->s.len = sizeof(struct carl9170_tx_superdesc) +
 139                      sizeof(struct ar9170_tx_hwdesc) +
 140                      sizeof(struct ieee80211_hdr);
 141         nullf->s.ri[0].tries = 3;
 142         nullf->s.assign_seq = true;
 143         nullf->s.queue = AR9170_TXQ_VO;
 144         nullf->f.hdr.length = sizeof(struct ieee80211_hdr) + FCS_LEN;
 145
 146         nullf->f.hdr.mac.backoff = 1;
 147         nullf->f.hdr.mac.hw_duration = 1;
 148         nullf->f.hdr.mac.erp_prot = AR9170_TX_MAC_PROT_RTS;
 149
 150         nullf->f.hdr.phy.modulation = AR9170_TX_PHY_MOD_OFDM;
 151         nullf->f.hdr.phy.bandwidth = AR9170_TX_PHY_BW_20MHZ;
 152         nullf->f.hdr.phy.chains = AR9170_TX_PHY_TXCHAIN_2;
 153         nullf->f.hdr.phy.tx_power = 29; /* 14.5 dBm */
 154         nullf->f.hdr.phy.mcs = AR9170_TXRX_PHY_RATE_OFDM_6M;
 155
 156         /* format outgoing nullfunc */
 157         null->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
 158                 IEEE80211_STYPE_NULLFUNC | IEEE80211_FCTL_TODS);
 159
 160         memcpy(null->addr1, fw.wol.cmd.bssid, 6);
 161         memcpy(null->addr2, fw.wol.cmd.mac, 6);
 162         memcpy(null->addr3, fw.wol.cmd.bssid, 6);
 163
 164         wlan_tx_fw(&nullf->s, wlan_wol_connect_callback);
 165 }
 166
 167 static bool wlan_rx_wol_disconnect(const unsigned int rx_filter,
 168                                    const struct ieee80211_hdr *hdr,
 169                                    const unsigned int __unused len)
 170 {
 171         const unsigned char *bssid;
 172         bssid = (const unsigned char *) AR9170_MAC_REG_BSSID_L;
 173
 174         /* should catch both broadcast and unicast MLMEs */
 175         if (!(rx_filter & CARL9170_RX_FILTER_OTHER_RA)) {
 176                 if (ieee80211_is_deauth(hdr->frame_control) ||
 177                     ieee80211_is_disassoc(hdr->frame_control))
 178                         return true;
 179         }
 180
 181         if (ieee80211_is_beacon(hdr->frame_control) &&
 182             compare_ether_address(hdr->addr3, bssid)) {
 183                 fw.wol.last_beacon = get_clock_counter();
 184         }
 185
 186         return false;
 187 }
 188
 189 #endif /* CARL9170FW_WOL_NL80211_TRIGGERS */
 190
 191 #ifdef CONFIG_CARL9170FW_WOL_PROBE_REQUEST
 192
 193 /*
 194  * Note: CONFIG_CARL9170FW_WOL_PROBE_REQUEST_SSID is not a real
 195  * string. We have to be careful not to add a \0 at the end.
 196  */
 197 static const struct {
 198         u8 ssid_ie;
 199         u8 ssid_len;
 200         u8 ssid[sizeof(CONFIG_CARL9170FW_WOL_PROBE_REQUEST_SSID) - 1];
 201 } __packed probe_req = {
 202         .ssid_ie = WLAN_EID_SSID,
 203         .ssid_len = sizeof(CONFIG_CARL9170FW_WOL_PROBE_REQUEST_SSID) - 1,
 204         .ssid = CONFIG_CARL9170FW_WOL_PROBE_REQUEST_SSID,
 205 };
 206
 207 static bool wlan_rx_wol_probe_ssid(const struct ieee80211_hdr *hdr, const unsigned int len)
 208 {
 209         const unsigned char *data, *end, *scan = (void *) &probe_req;
 210
 211         /*
 212          * IEEE 802.11-2007 7.3.2.1 specifies that the SSID is no
 213          * longer than 32 octets.
 214          */
 215         BUILD_BUG_ON((sizeof(CONFIG_CARL9170FW_WOL_PROBE_REQUEST_SSID) - 1) > 32);
 216
 217         if (ieee80211_is_probe_req(hdr->frame_control)) {
 218                 unsigned int i;
 219                 end = (u8 *)((unsigned long)hdr + len);
 220
 221                 /*
 222                  * The position of the SSID information element inside
 223                  * a probe request frame is more or less "fixed".
 224                  */
 225                 data = (u8 *)((struct ieee80211_mgmt *)hdr)->u.probe_req.variable;
 226                 for (i = 0; i < (unsigned int)(probe_req.ssid_len + 1); i++) {
 227                         if (data > end || scan[i] != data[i])
 228                                 return false;
 229                 }
 230
 231                 return true;
 232         }
 233
 234         return false;
 235 }
 236 #endif /* CONFIG_CARL9170FW_WOL_PROBE_REQUEST */
 237
 238 void wol_rx(const unsigned int rx_filter __unused, const struct ieee80211_hdr *hdr __unused, const unsigned int len __unused)
 239 {
 240 #ifdef CONFIG_CARL9170FW_WOL_NL80211_TRIGGERS
 241         /* Disconnect is always enabled */
 242         if (fw.wol.cmd.flags & CARL9170_WOL_DISCONNECT &&
 243             rx_filter & CARL9170_RX_FILTER_MGMT)
 244                 fw.wol.wake_up |= wlan_rx_wol_disconnect(rx_filter, hdr, len);
 245
 246         if (fw.wol.cmd.flags & CARL9170_WOL_MAGIC_PKT &&
 247             rx_filter & CARL9170_RX_FILTER_DATA)
 248                 fw.wol.wake_up |= wlan_rx_wol_magic_packet(hdr, len);
 249 #endif /* CONFIG_CARL9170FW_WOL_NL80211_TRIGGERS */
 250
 251 #ifdef CONFIG_CARL9170FW_WOL_PROBE_REQUEST
 252         if (rx_filter & CARL9170_RX_FILTER_MGMT)
 253                 fw.wol.wake_up |= wlan_rx_wol_probe_ssid(hdr, len);
 254 #endif /* CONFIG_CARL9170FW_WOL_PROBE_REQUEST */
 255 }
 256
 257 void wol_janitor(void)
 258 {
 259         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 260 #ifdef CONFIG_CARL9170FW_WOL_NL80211_TRIGGERS
 261                 if (fw.wol.cmd.flags & CARL9170_WOL_DISCONNECT) {
 262                         /*
 263                          * connection lost after 10sec without receiving
 264                          * a beacon
 265                           */
 266                         if (is_after_msecs(fw.wol.last_beacon, 10000))
 267                                 fw.wol.wake_up |= true;
 268
 269                         if (fw.wol.cmd.null_interval &&
 270                             is_after_msecs(fw.wol.last_null, fw.wol.cmd.null_interval))
 271                                 wlan_wol_connection_monitor();
 272
 273                         if (fw.wol.lost_null >= 5)
 274                                 fw.wol.wake_up |= true;
 275                 }
 276 #endif /* CONFIG_CARL9170FW_WOL_NL80211_TRIGGERS */
 277
 278                 if (fw.wol.wake_up) {
 279                         fw.suspend_mode = CARL9170_AWAKE_HOST;
 280                         set(AR9170_USB_REG_WAKE_UP, AR9170_USB_WAKE_UP_WAKE);
 281                 }
 282         }
 283 }
 284 #else
 285
 286 #endif /* CONFIG_CARL9170FW_WOL */