SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/usb/wusbcore/security.c

   1 /*
   2  * Wireless USB Host Controller
   3  * Security support: encryption enablement, etc
   4  *
   5  * Copyright (C) 2006 Intel Corporation
   6  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License version
  10  * 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20  * 02110-1301, USA.
  21  *
  22  *
  23  * FIXME: docs
  24  */
  25 #include <linux/types.h>
  26 #include <linux/usb/ch9.h>
  27 #include <linux/random.h>
  28 #include "wusbhc.h"
  29
  30 static void wusbhc_set_gtk_callback(struct urb *urb);
  31 static void wusbhc_gtk_rekey_done_work(struct work_struct *work);
  32
  33 int wusbhc_sec_create(struct wusbhc *wusbhc)
  34 {
  35         wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) + sizeof(wusbhc->gtk.data);
  36         wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
  37         wusbhc->gtk.descr.bReserved = 0;
  38
  39         wusbhc->gtk_index = wusb_key_index(0, WUSB_KEY_INDEX_TYPE_GTK,
  40                                            WUSB_KEY_INDEX_ORIGINATOR_HOST);
  41
  42         INIT_WORK(&wusbhc->gtk_rekey_done_work, wusbhc_gtk_rekey_done_work);
  43
  44         return 0;
  45 }
  46
  47
  48 /* Called when the HC is destroyed */
  49 void wusbhc_sec_destroy(struct wusbhc *wusbhc)
  50 {
  51 }
  52
  53
  54 /**
  55  * wusbhc_next_tkid - generate a new, currently unused, TKID
  56  * @wusbhc:   the WUSB host controller
  57  * @wusb_dev: the device whose PTK the TKID is for
  58  *            (or NULL for a TKID for a GTK)
  59  *
  60  * The generated TKID consist of two parts: the device's authenicated
  61  * address (or 0 or a GTK); and an incrementing number.  This ensures
  62  * that TKIDs cannot be shared between devices and by the time the
  63  * incrementing number wraps around the older TKIDs will no longer be
  64  * in use (a maximum of two keys may be active at any one time).
  65  */
  66 static u32 wusbhc_next_tkid(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
  67 {
  68         u32 *tkid;
  69         u32 addr;
  70
  71         if (wusb_dev == NULL) {
  72                 tkid = &wusbhc->gtk_tkid;
  73                 addr = 0;
  74         } else {
  75                 tkid = &wusb_port_by_idx(wusbhc, wusb_dev->port_idx)->ptk_tkid;
  76                 addr = wusb_dev->addr & 0x7f;
  77         }
  78
  79         *tkid = (addr << 8) | ((*tkid + 1) & 0xff);
  80
  81         return *tkid;
  82 }
  83
  84 static void wusbhc_generate_gtk(struct wusbhc *wusbhc)
  85 {
  86         const size_t key_size = sizeof(wusbhc->gtk.data);
  87         u32 tkid;
  88
  89         tkid = wusbhc_next_tkid(wusbhc, NULL);
  90
  91         wusbhc->gtk.descr.tTKID[0] = (tkid >>  0) & 0xff;
  92         wusbhc->gtk.descr.tTKID[1] = (tkid >>  8) & 0xff;
  93         wusbhc->gtk.descr.tTKID[2] = (tkid >> 16) & 0xff;
  94
  95         get_random_bytes(wusbhc->gtk.descr.bKeyData, key_size);
  96 }
  97
  98 /**
  99  * wusbhc_sec_start - start the security management process
 100  * @wusbhc: the WUSB host controller
 101  *
 102  * Generate and set an initial GTK on the host controller.
 103  *
 104  * Called when the HC is started.
 105  */
 106 int wusbhc_sec_start(struct wusbhc *wusbhc)
 107 {
 108         const size_t key_size = sizeof(wusbhc->gtk.data);
 109         int result;
 110
 111         wusbhc_generate_gtk(wusbhc);
 112
 113         result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
 114                                  &wusbhc->gtk.descr.bKeyData, key_size);
 115         if (result < 0)
 116                 dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n",
 117                         result);
 118
 119         return result;
 120 }
 121
 122 /**
 123  * wusbhc_sec_stop - stop the security management process
 124  * @wusbhc: the WUSB host controller
 125  *
 126  * Wait for any pending GTK rekeys to stop.
 127  */
 128 void wusbhc_sec_stop(struct wusbhc *wusbhc)
 129 {
 130         cancel_work_sync(&wusbhc->gtk_rekey_done_work);
 131 }
 132
 133
 134 /** @returns encryption type name */
 135 const char *wusb_et_name(u8 x)
 136 {
 137         switch (x) {
 138         case USB_ENC_TYPE_UNSECURE:     return "unsecure";
 139         case USB_ENC_TYPE_WIRED:        return "wired";
 140         case USB_ENC_TYPE_CCM_1:        return "CCM-1";
 141         case USB_ENC_TYPE_RSA_1:        return "RSA-1";
 142         default:                        return "unknown";
 143         }
 144 }
 145 EXPORT_SYMBOL_GPL(wusb_et_name);
 146
 147 /*
 148  * Set the device encryption method
 149  *
 150  * We tell the device which encryption method to use; we do this when
 151  * setting up the device's security.
 152  */
 153 static int wusb_dev_set_encryption(struct usb_device *usb_dev, int value)
 154 {
 155         int result;
 156         struct device *dev = &usb_dev->dev;
 157         struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
 158
 159         if (value) {
 160                 value = wusb_dev->ccm1_etd.bEncryptionValue;
 161         } else {
 162                 /* FIXME: should be wusb_dev->etd[UNSECURE].bEncryptionValue */
 163                 value = 0;
 164         }
 165         /* Set device's */
 166         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
 167                         USB_REQ_SET_ENCRYPTION,
 168                         USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
 169                         value, 0, NULL, 0, 1000 /* FIXME: arbitrary */);
 170         if (result < 0)
 171                 dev_err(dev, "Can't set device's WUSB encryption to "
 172                         "%s (value %d): %d\n",
 173                         wusb_et_name(wusb_dev->ccm1_etd.bEncryptionType),
 174                         wusb_dev->ccm1_etd.bEncryptionValue,  result);
 175         return result;
 176 }
 177
 178 /*
 179  * Set the GTK to be used by a device.
 180  *
 181  * The device must be authenticated.
 182  */
 183 static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
 184 {
 185         struct usb_device *usb_dev = wusb_dev->usb_dev;
 186
 187         return usb_control_msg(
 188                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
 189                 USB_REQ_SET_DESCRIPTOR,
 190                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
 191                 USB_DT_KEY << 8 | wusbhc->gtk_index, 0,
 192                 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
 193                 1000);
 194 }
 195
 196
 197 /* FIXME: prototype for adding security */
 198 int wusb_dev_sec_add(struct wusbhc *wusbhc,
 199                      struct usb_device *usb_dev, struct wusb_dev *wusb_dev)
 200 {
 201         int result, bytes, secd_size;
 202         struct device *dev = &usb_dev->dev;
 203         struct usb_security_descriptor *secd;
 204         const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
 205         const void *itr, *top;
 206         char buf[64];
 207
 208         secd = kmalloc(sizeof(struct usb_security_descriptor), GFP_KERNEL);
 209         if (secd == NULL) {
 210                 result = -ENOMEM;
 211                 goto out;
 212         }
 213
 214         result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
 215                                     0, secd, sizeof(struct usb_security_descriptor));
 216         if (result < sizeof(secd)) {
 217                 dev_err(dev, "Can't read security descriptor or "
 218                         "not enough data: %d\n", result);
 219                 goto out;
 220         }
 221         secd_size = le16_to_cpu(secd->wTotalLength);
 222         secd = krealloc(secd, secd_size, GFP_KERNEL);
 223         if (secd == NULL) {
 224                 dev_err(dev, "Can't allocate space for security descriptors\n");
 225                 goto out;
 226         }
 227         result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
 228                                     0, secd, secd_size);
 229         if (result < secd_size) {
 230                 dev_err(dev, "Can't read security descriptor or "
 231                         "not enough data: %d\n", result);
 232                 goto out;
 233         }
 234         bytes = 0;
 235         itr = &secd[1];
 236         top = (void *)secd + result;
 237         while (itr < top) {
 238                 etd = itr;
 239                 if (top - itr < sizeof(*etd)) {
 240                         dev_err(dev, "BUG: bad device security descriptor; "
 241                                 "not enough data (%zu vs %zu bytes left)\n",
 242                                 top - itr, sizeof(*etd));
 243                         break;
 244                 }
 245                 if (etd->bLength < sizeof(*etd)) {
 246                         dev_err(dev, "BUG: bad device encryption descriptor; "
 247                                 "descriptor is too short "
 248                                 "(%u vs %zu needed)\n",
 249                                 etd->bLength, sizeof(*etd));
 250                         break;
 251                 }
 252                 itr += etd->bLength;
 253                 bytes += snprintf(buf + bytes, sizeof(buf) - bytes,
 254                                   "%s (0x%02x/%02x) ",
 255                                   wusb_et_name(etd->bEncryptionType),
 256                                   etd->bEncryptionValue, etd->bAuthKeyIndex);
 257                 if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1)
 258                         ccm1_etd = etd;
 259         }
 260         /* This code only supports CCM1 as of now. */
 261         /* FIXME: user has to choose which sec mode to use?
 262          * In theory we want CCM */
 263         if (ccm1_etd == NULL) {
 264                 dev_err(dev, "WUSB device doesn't support CCM1 encryption, "
 265                         "can't use!\n");
 266                 result = -EINVAL;
 267                 goto out;
 268         }
 269         wusb_dev->ccm1_etd = *ccm1_etd;
 270         dev_dbg(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n",
 271                 buf, wusb_et_name(ccm1_etd->bEncryptionType),
 272                 ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex);
 273         result = 0;
 274 out:
 275         kfree(secd);
 276         return result;
 277 }
 278
 279 void wusb_dev_sec_rm(struct wusb_dev *wusb_dev)
 280 {
 281         /* Nothing so far */
 282 }
 283
 284 /**
 285  * Update the address of an unauthenticated WUSB device
 286  *
 287  * Once we have successfully authenticated, we take it to addr0 state
 288  * and then to a normal address.
 289  *
 290  * Before the device's address (as known by it) was usb_dev->devnum |
 291  * 0x80 (unauthenticated address). With this we update it to usb_dev->devnum.
 292  */
 293 int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
 294 {
 295         int result = -ENOMEM;
 296         struct usb_device *usb_dev = wusb_dev->usb_dev;
 297         struct device *dev = &usb_dev->dev;
 298         u8 new_address = wusb_dev->addr & 0x7F;
 299
 300         /* Set address 0 */
 301         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
 302                                  USB_REQ_SET_ADDRESS, 0,
 303                                  0, 0, NULL, 0, 1000 /* FIXME: arbitrary */);
 304         if (result < 0) {
 305                 dev_err(dev, "auth failed: can't set address 0: %d\n",
 306                         result);
 307                 goto error_addr0;
 308         }
 309         result = wusb_set_dev_addr(wusbhc, wusb_dev, 0);
 310         if (result < 0)
 311                 goto error_addr0;
 312         usb_set_device_state(usb_dev, USB_STATE_DEFAULT);
 313         usb_ep0_reinit(usb_dev);
 314
 315         /* Set new (authenticated) address. */
 316         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
 317                                  USB_REQ_SET_ADDRESS, 0,
 318                                  new_address, 0, NULL, 0,
 319                                  1000 /* FIXME: arbitrary */);
 320         if (result < 0) {
 321                 dev_err(dev, "auth failed: can't set address %u: %d\n",
 322                         new_address, result);
 323                 goto error_addr;
 324         }
 325         result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address);
 326         if (result < 0)
 327                 goto error_addr;
 328         usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
 329         usb_ep0_reinit(usb_dev);
 330         usb_dev->authenticated = 1;
 331 error_addr:
 332 error_addr0:
 333         return result;
 334 }
 335
 336 /*
 337  *
 338  *
 339  */
 340 /* FIXME: split and cleanup */
 341 int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev,
 342                             struct wusb_ckhdid *ck)
 343 {
 344         int result = -ENOMEM;
 345         struct usb_device *usb_dev = wusb_dev->usb_dev;
 346         struct device *dev = &usb_dev->dev;
 347         u32 tkid;
 348         __le32 tkid_le;
 349         struct usb_handshake *hs;
 350         struct aes_ccm_nonce ccm_n;
 351         u8 mic[8];
 352         struct wusb_keydvt_in keydvt_in;
 353         struct wusb_keydvt_out keydvt_out;
 354
 355         hs = kzalloc(3*sizeof(hs[0]), GFP_KERNEL);
 356         if (hs == NULL) {
 357                 dev_err(dev, "can't allocate handshake data\n");
 358                 goto error_kzalloc;
 359         }
 360
 361         /* We need to turn encryption before beginning the 4way
 362          * hshake (WUSB1.0[.3.2.2]) */
 363         result = wusb_dev_set_encryption(usb_dev, 1);
 364         if (result < 0)
 365                 goto error_dev_set_encryption;
 366
 367         tkid = wusbhc_next_tkid(wusbhc, wusb_dev);
 368         tkid_le = cpu_to_le32(tkid);
 369
 370         hs[0].bMessageNumber = 1;
 371         hs[0].bStatus = 0;
 372         memcpy(hs[0].tTKID, &tkid_le, sizeof(hs[0].tTKID));
 373         hs[0].bReserved = 0;
 374         memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID));
 375         get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce));
 376         memset(hs[0].MIC, 0, sizeof(hs[0].MIC));        /* Per WUSB1.0[T7-22] */
 377
 378         result = usb_control_msg(
 379                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
 380                 USB_REQ_SET_HANDSHAKE,
 381                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
 382                 1, 0, &hs[0], sizeof(hs[0]), 1000 /* FIXME: arbitrary */);
 383         if (result < 0) {
 384                 dev_err(dev, "Handshake1: request failed: %d\n", result);
 385                 goto error_hs1;
 386         }
 387
 388         /* Handshake 2, from the device -- need to verify fields */
 389         result = usb_control_msg(
 390                 usb_dev, usb_rcvctrlpipe(usb_dev, 0),
 391                 USB_REQ_GET_HANDSHAKE,
 392                 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
 393                 2, 0, &hs[1], sizeof(hs[1]), 1000 /* FIXME: arbitrary */);
 394         if (result < 0) {
 395                 dev_err(dev, "Handshake2: request failed: %d\n", result);
 396                 goto error_hs2;
 397         }
 398
 399         result = -EINVAL;
 400         if (hs[1].bMessageNumber != 2) {
 401                 dev_err(dev, "Handshake2 failed: bad message number %u\n",
 402                         hs[1].bMessageNumber);
 403                 goto error_hs2;
 404         }
 405         if (hs[1].bStatus != 0) {
 406                 dev_err(dev, "Handshake2 failed: bad status %u\n",
 407                         hs[1].bStatus);
 408                 goto error_hs2;
 409         }
 410         if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) {
 411                 dev_err(dev, "Handshake2 failed: TKID mismatch "
 412                         "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n",
 413                         hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2],
 414                         hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]);
 415                 goto error_hs2;
 416         }
 417         if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) {
 418                 dev_err(dev, "Handshake2 failed: CDID mismatch\n");
 419                 goto error_hs2;
 420         }
 421
 422         /* Setup the CCM nonce */
 423         memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn));       /* Per WUSB1.0[6.5.2] */
 424         memcpy(ccm_n.tkid, &tkid_le, sizeof(ccm_n.tkid));
 425         ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr;
 426         ccm_n.dest_addr.data[0] = wusb_dev->addr;
 427         ccm_n.dest_addr.data[1] = 0;
 428
 429         /* Derive the KCK and PTK from CK, the CCM, H and D nonces */
 430         memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce));
 431         memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce));
 432         result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in);
 433         if (result < 0) {
 434                 dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n",
 435                         result);
 436                 goto error_hs2;
 437         }
 438
 439         /* Compute MIC and verify it */
 440         result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]);
 441         if (result < 0) {
 442                 dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n",
 443                         result);
 444                 goto error_hs2;
 445         }
 446
 447         if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) {
 448                 dev_err(dev, "Handshake2 failed: MIC mismatch\n");
 449                 goto error_hs2;
 450         }
 451
 452         /* Send Handshake3 */
 453         hs[2].bMessageNumber = 3;
 454         hs[2].bStatus = 0;
 455         memcpy(hs[2].tTKID, &tkid_le, sizeof(hs[2].tTKID));
 456         hs[2].bReserved = 0;
 457         memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID));
 458         memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce));
 459         result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]);
 460         if (result < 0) {
 461                 dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n",
 462                         result);
 463                 goto error_hs2;
 464         }
 465
 466         result = usb_control_msg(
 467                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
 468                 USB_REQ_SET_HANDSHAKE,
 469                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
 470                 3, 0, &hs[2], sizeof(hs[2]), 1000 /* FIXME: arbitrary */);
 471         if (result < 0) {
 472                 dev_err(dev, "Handshake3: request failed: %d\n", result);
 473                 goto error_hs3;
 474         }
 475
 476         result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid,
 477                                  keydvt_out.ptk, sizeof(keydvt_out.ptk));
 478         if (result < 0)
 479                 goto error_wusbhc_set_ptk;
 480
 481         result = wusb_dev_set_gtk(wusbhc, wusb_dev);
 482         if (result < 0) {
 483                 dev_err(dev, "Set GTK for device: request failed: %d\n",
 484                         result);
 485                 goto error_wusbhc_set_gtk;
 486         }
 487
 488         /* Update the device's address from unauth to auth */
 489         if (usb_dev->authenticated == 0) {
 490                 result = wusb_dev_update_address(wusbhc, wusb_dev);
 491                 if (result < 0)
 492                         goto error_dev_update_address;
 493         }
 494         result = 0;
 495         dev_info(dev, "device authenticated\n");
 496
 497 error_dev_update_address:
 498 error_wusbhc_set_gtk:
 499 error_wusbhc_set_ptk:
 500 error_hs3:
 501 error_hs2:
 502 error_hs1:
 503         memset(hs, 0, 3*sizeof(hs[0]));
 504         memset(&keydvt_out, 0, sizeof(keydvt_out));
 505         memset(&keydvt_in, 0, sizeof(keydvt_in));
 506         memset(&ccm_n, 0, sizeof(ccm_n));
 507         memset(mic, 0, sizeof(mic));
 508         if (result < 0)
 509                 wusb_dev_set_encryption(usb_dev, 0);
 510 error_dev_set_encryption:
 511         kfree(hs);
 512 error_kzalloc:
 513         return result;
 514 }
 515
 516 /*
 517  * Once all connected and authenticated devices have received the new
 518  * GTK, switch the host to using it.
 519  */
 520 static void wusbhc_gtk_rekey_done_work(struct work_struct *work)
 521 {
 522         struct wusbhc *wusbhc = container_of(work, struct wusbhc, gtk_rekey_done_work);
 523         size_t key_size = sizeof(wusbhc->gtk.data);
 524
 525         mutex_lock(&wusbhc->mutex);
 526
 527         if (--wusbhc->pending_set_gtks == 0)
 528                 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
 529
 530         mutex_unlock(&wusbhc->mutex);
 531 }
 532
 533 static void wusbhc_set_gtk_callback(struct urb *urb)
 534 {
 535         struct wusbhc *wusbhc = urb->context;
 536
 537         queue_work(wusbd, &wusbhc->gtk_rekey_done_work);
 538 }
 539
 540 /**
 541  * wusbhc_gtk_rekey - generate and distribute a new GTK
 542  * @wusbhc: the WUSB host controller
 543  *
 544  * Generate a new GTK and distribute it to all connected and
 545  * authenticated devices.  When all devices have the new GTK, the host
 546  * starts using it.
 547  *
 548  * This must be called after every device disconnect (see [WUSB]
 549  * section 6.2.11.2).
 550  */
 551 void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
 552 {
 553         static const size_t key_size = sizeof(wusbhc->gtk.data);
 554         int p;
 555
 556         wusbhc_generate_gtk(wusbhc);
 557
 558         for (p = 0; p < wusbhc->ports_max; p++) {
 559                 struct wusb_dev *wusb_dev;
 560
 561                 wusb_dev = wusbhc->port[p].wusb_dev;
 562                 if (!wusb_dev || !wusb_dev->usb_dev || !wusb_dev->usb_dev->authenticated)
 563                         continue;
 564
 565                 usb_fill_control_urb(wusb_dev->set_gtk_urb, wusb_dev->usb_dev,
 566                                      usb_sndctrlpipe(wusb_dev->usb_dev, 0),
 567                                      (void *)wusb_dev->set_gtk_req,
 568                                      &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
 569                                      wusbhc_set_gtk_callback, wusbhc);
 570                 if (usb_submit_urb(wusb_dev->set_gtk_urb, GFP_KERNEL) == 0)
 571                         wusbhc->pending_set_gtks++;
 572         }
 573         if (wusbhc->pending_set_gtks == 0)
 574                 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
 575 }