wusb: reset WUSB devices with SetAddress(0)
[linux-2.6.git] / 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 /*
31  * DEBUG & SECURITY WARNING!!!!
32  *
33  * If you enable this past 1, the debug code will weaken the
34  * cryptographic safety of the system (on purpose, for debugging).
35  *
36  * Weaken means:
37  *   we print secret keys and intermediate values all the way,
38  */
39 #undef D_LOCAL
40 #define D_LOCAL 2
41 #include <linux/uwb/debug.h>
42
43 static void wusbhc_set_gtk_callback(struct urb *urb);
44 static void wusbhc_gtk_rekey_done_work(struct work_struct *work);
45
46 int wusbhc_sec_create(struct wusbhc *wusbhc)
47 {
48         wusbhc->gtk.descr.bLength = sizeof(wusbhc->gtk.descr) + sizeof(wusbhc->gtk.data);
49         wusbhc->gtk.descr.bDescriptorType = USB_DT_KEY;
50         wusbhc->gtk.descr.bReserved = 0;
51
52         wusbhc->gtk_index = wusb_key_index(0, WUSB_KEY_INDEX_TYPE_GTK,
53                                            WUSB_KEY_INDEX_ORIGINATOR_HOST);
54
55         INIT_WORK(&wusbhc->gtk_rekey_done_work, wusbhc_gtk_rekey_done_work);
56
57         return 0;
58 }
59
60
61 /* Called when the HC is destroyed */
62 void wusbhc_sec_destroy(struct wusbhc *wusbhc)
63 {
64 }
65
66
67 /**
68  * wusbhc_next_tkid - generate a new, currently unused, TKID
69  * @wusbhc:   the WUSB host controller
70  * @wusb_dev: the device whose PTK the TKID is for
71  *            (or NULL for a TKID for a GTK)
72  *
73  * The generated TKID consist of two parts: the device's authenicated
74  * address (or 0 or a GTK); and an incrementing number.  This ensures
75  * that TKIDs cannot be shared between devices and by the time the
76  * incrementing number wraps around the older TKIDs will no longer be
77  * in use (a maximum of two keys may be active at any one time).
78  */
79 static u32 wusbhc_next_tkid(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
80 {
81         u32 *tkid;
82         u32 addr;
83
84         if (wusb_dev == NULL) {
85                 tkid = &wusbhc->gtk_tkid;
86                 addr = 0;
87         } else {
88                 tkid = &wusb_port_by_idx(wusbhc, wusb_dev->port_idx)->ptk_tkid;
89                 addr = wusb_dev->addr & 0x7f;
90         }
91
92         *tkid = (addr << 8) | ((*tkid + 1) & 0xff);
93
94         return *tkid;
95 }
96
97 static void wusbhc_generate_gtk(struct wusbhc *wusbhc)
98 {
99         const size_t key_size = sizeof(wusbhc->gtk.data);
100         u32 tkid;
101
102         tkid = wusbhc_next_tkid(wusbhc, NULL);
103
104         wusbhc->gtk.descr.tTKID[0] = (tkid >>  0) & 0xff;
105         wusbhc->gtk.descr.tTKID[1] = (tkid >>  8) & 0xff;
106         wusbhc->gtk.descr.tTKID[2] = (tkid >> 16) & 0xff;
107
108         get_random_bytes(wusbhc->gtk.descr.bKeyData, key_size);
109 }
110
111 /**
112  * wusbhc_sec_start - start the security management process
113  * @wusbhc: the WUSB host controller
114  *
115  * Generate and set an initial GTK on the host controller.
116  *
117  * Called when the HC is started.
118  */
119 int wusbhc_sec_start(struct wusbhc *wusbhc)
120 {
121         const size_t key_size = sizeof(wusbhc->gtk.data);
122         int result;
123
124         wusbhc_generate_gtk(wusbhc);
125
126         result = wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid,
127                                  &wusbhc->gtk.descr.bKeyData, key_size);
128         if (result < 0)
129                 dev_err(wusbhc->dev, "cannot set GTK for the host: %d\n",
130                         result);
131
132         return result;
133 }
134
135 /**
136  * wusbhc_sec_stop - stop the security management process
137  * @wusbhc: the WUSB host controller
138  *
139  * Wait for any pending GTK rekeys to stop.
140  */
141 void wusbhc_sec_stop(struct wusbhc *wusbhc)
142 {
143         cancel_work_sync(&wusbhc->gtk_rekey_done_work);
144 }
145
146
147 /** @returns encryption type name */
148 const char *wusb_et_name(u8 x)
149 {
150         switch (x) {
151         case USB_ENC_TYPE_UNSECURE:     return "unsecure";
152         case USB_ENC_TYPE_WIRED:        return "wired";
153         case USB_ENC_TYPE_CCM_1:        return "CCM-1";
154         case USB_ENC_TYPE_RSA_1:        return "RSA-1";
155         default:                        return "unknown";
156         }
157 }
158 EXPORT_SYMBOL_GPL(wusb_et_name);
159
160 /*
161  * Set the device encryption method
162  *
163  * We tell the device which encryption method to use; we do this when
164  * setting up the device's security.
165  */
166 static int wusb_dev_set_encryption(struct usb_device *usb_dev, int value)
167 {
168         int result;
169         struct device *dev = &usb_dev->dev;
170         struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
171
172         if (value) {
173                 value = wusb_dev->ccm1_etd.bEncryptionValue;
174         } else {
175                 /* FIXME: should be wusb_dev->etd[UNSECURE].bEncryptionValue */
176                 value = 0;
177         }
178         /* Set device's */
179         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
180                         USB_REQ_SET_ENCRYPTION,
181                         USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
182                         value, 0, NULL, 0, 1000 /* FIXME: arbitrary */);
183         if (result < 0)
184                 dev_err(dev, "Can't set device's WUSB encryption to "
185                         "%s (value %d): %d\n",
186                         wusb_et_name(wusb_dev->ccm1_etd.bEncryptionType),
187                         wusb_dev->ccm1_etd.bEncryptionValue,  result);
188         return result;
189 }
190
191 /*
192  * Set the GTK to be used by a device.
193  *
194  * The device must be authenticated.
195  */
196 static int wusb_dev_set_gtk(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
197 {
198         struct usb_device *usb_dev = wusb_dev->usb_dev;
199
200         return usb_control_msg(
201                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
202                 USB_REQ_SET_DESCRIPTOR,
203                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
204                 USB_DT_KEY << 8 | wusbhc->gtk_index, 0,
205                 &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
206                 1000);
207 }
208
209
210 /* FIXME: prototype for adding security */
211 int wusb_dev_sec_add(struct wusbhc *wusbhc,
212                      struct usb_device *usb_dev, struct wusb_dev *wusb_dev)
213 {
214         int result, bytes, secd_size;
215         struct device *dev = &usb_dev->dev;
216         struct usb_security_descriptor secd;
217         const struct usb_encryption_descriptor *etd, *ccm1_etd = NULL;
218         void *secd_buf;
219         const void *itr, *top;
220         char buf[64];
221
222         d_fnstart(3, dev, "(usb_dev %p, wusb_dev %p)\n", usb_dev, wusb_dev);
223         result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
224                                     0, &secd, sizeof(secd));
225         if (result < sizeof(secd)) {
226                 dev_err(dev, "Can't read security descriptor or "
227                         "not enough data: %d\n", result);
228                 goto error_secd;
229         }
230         secd_size = le16_to_cpu(secd.wTotalLength);
231         d_printf(5, dev, "got %d bytes of sec descriptor, total is %d\n",
232                  result, secd_size);
233         secd_buf = kmalloc(secd_size, GFP_KERNEL);
234         if (secd_buf == NULL) {
235                 dev_err(dev, "Can't allocate space for security descriptors\n");
236                 goto error_secd_alloc;
237         }
238         result = usb_get_descriptor(usb_dev, USB_DT_SECURITY,
239                                     0, secd_buf, secd_size);
240         if (result < secd_size) {
241                 dev_err(dev, "Can't read security descriptor or "
242                         "not enough data: %d\n", result);
243                 goto error_secd_all;
244         }
245         d_printf(5, dev, "got %d bytes of sec descriptors\n", result);
246         bytes = 0;
247         itr = secd_buf + sizeof(secd);
248         top = secd_buf + result;
249         while (itr < top) {
250                 etd = itr;
251                 if (top - itr < sizeof(*etd)) {
252                         dev_err(dev, "BUG: bad device security descriptor; "
253                                 "not enough data (%zu vs %zu bytes left)\n",
254                                 top - itr, sizeof(*etd));
255                         break;
256                 }
257                 if (etd->bLength < sizeof(*etd)) {
258                         dev_err(dev, "BUG: bad device encryption descriptor; "
259                                 "descriptor is too short "
260                                 "(%u vs %zu needed)\n",
261                                 etd->bLength, sizeof(*etd));
262                         break;
263                 }
264                 itr += etd->bLength;
265                 bytes += snprintf(buf + bytes, sizeof(buf) - bytes,
266                                   "%s (0x%02x/%02x) ",
267                                   wusb_et_name(etd->bEncryptionType),
268                                   etd->bEncryptionValue, etd->bAuthKeyIndex);
269                 if (etd->bEncryptionType == USB_ENC_TYPE_CCM_1)
270                         ccm1_etd = etd;
271         }
272         /* This code only supports CCM1 as of now. */
273         /* FIXME: user has to choose which sec mode to use?
274          * In theory we want CCM */
275         if (ccm1_etd == NULL) {
276                 dev_err(dev, "WUSB device doesn't support CCM1 encryption, "
277                         "can't use!\n");
278                 result = -EINVAL;
279                 goto error_no_ccm1;
280         }
281         wusb_dev->ccm1_etd = *ccm1_etd;
282         dev_info(dev, "supported encryption: %s; using %s (0x%02x/%02x)\n",
283                  buf, wusb_et_name(ccm1_etd->bEncryptionType),
284                  ccm1_etd->bEncryptionValue, ccm1_etd->bAuthKeyIndex);
285         result = 0;
286         kfree(secd_buf);
287 out:
288         d_fnend(3, dev, "(usb_dev %p, wusb_dev %p) = %d\n",
289                 usb_dev, wusb_dev, result);
290         return result;
291
292
293 error_no_ccm1:
294 error_secd_all:
295         kfree(secd_buf);
296 error_secd_alloc:
297 error_secd:
298         goto out;
299 }
300
301 void wusb_dev_sec_rm(struct wusb_dev *wusb_dev)
302 {
303         /* Nothing so far */
304 }
305
306 static void hs_printk(unsigned level, struct device *dev,
307                       struct usb_handshake *hs)
308 {
309         d_printf(level, dev,
310                  "  bMessageNumber: %u\n"
311                  "  bStatus:        %u\n"
312                  "  tTKID:          %02x %02x %02x\n"
313                  "  CDID:           %02x %02x %02x %02x %02x %02x %02x %02x\n"
314                  "                  %02x %02x %02x %02x %02x %02x %02x %02x\n"
315                  "  nonce:          %02x %02x %02x %02x %02x %02x %02x %02x\n"
316                  "                  %02x %02x %02x %02x %02x %02x %02x %02x\n"
317                  "  MIC:            %02x %02x %02x %02x %02x %02x %02x %02x\n",
318                  hs->bMessageNumber, hs->bStatus,
319                  hs->tTKID[2], hs->tTKID[1], hs->tTKID[0],
320                  hs->CDID[0], hs->CDID[1], hs->CDID[2], hs->CDID[3],
321                  hs->CDID[4], hs->CDID[5], hs->CDID[6], hs->CDID[7],
322                  hs->CDID[8], hs->CDID[9], hs->CDID[10], hs->CDID[11],
323                  hs->CDID[12], hs->CDID[13], hs->CDID[14], hs->CDID[15],
324                  hs->nonce[0], hs->nonce[1], hs->nonce[2], hs->nonce[3],
325                  hs->nonce[4], hs->nonce[5], hs->nonce[6], hs->nonce[7],
326                  hs->nonce[8], hs->nonce[9], hs->nonce[10], hs->nonce[11],
327                  hs->nonce[12], hs->nonce[13], hs->nonce[14], hs->nonce[15],
328                  hs->MIC[0], hs->MIC[1], hs->MIC[2], hs->MIC[3],
329                  hs->MIC[4], hs->MIC[5], hs->MIC[6], hs->MIC[7]);
330 }
331
332 /**
333  * Update the address of an unauthenticated WUSB device
334  *
335  * Once we have successfully authenticated, we take it to addr0 state
336  * and then to a normal address.
337  *
338  * Before the device's address (as known by it) was usb_dev->devnum |
339  * 0x80 (unauthenticated address). With this we update it to usb_dev->devnum.
340  */
341 int wusb_dev_update_address(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
342 {
343         int result = -ENOMEM;
344         struct usb_device *usb_dev = wusb_dev->usb_dev;
345         struct device *dev = &usb_dev->dev;
346         u8 new_address = wusb_dev->addr & 0x7F;
347
348         /* Set address 0 */
349         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
350                                  USB_REQ_SET_ADDRESS, 0,
351                                  0, 0, NULL, 0, 1000 /* FIXME: arbitrary */);
352         if (result < 0) {
353                 dev_err(dev, "auth failed: can't set address 0: %d\n",
354                         result);
355                 goto error_addr0;
356         }
357         result = wusb_set_dev_addr(wusbhc, wusb_dev, 0);
358         if (result < 0)
359                 goto error_addr0;
360         usb_ep0_reinit(usb_dev);
361
362         /* Set new (authenticated) address. */
363         result = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
364                                  USB_REQ_SET_ADDRESS, 0,
365                                  new_address, 0, NULL, 0,
366                                  1000 /* FIXME: arbitrary */);
367         if (result < 0) {
368                 dev_err(dev, "auth failed: can't set address %u: %d\n",
369                         new_address, result);
370                 goto error_addr;
371         }
372         result = wusb_set_dev_addr(wusbhc, wusb_dev, new_address);
373         if (result < 0)
374                 goto error_addr;
375         usb_ep0_reinit(usb_dev);
376         usb_dev->authenticated = 1;
377 error_addr:
378 error_addr0:
379         return result;
380 }
381
382 /*
383  *
384  *
385  */
386 /* FIXME: split and cleanup */
387 int wusb_dev_4way_handshake(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev,
388                             struct wusb_ckhdid *ck)
389 {
390         int result = -ENOMEM;
391         struct usb_device *usb_dev = wusb_dev->usb_dev;
392         struct device *dev = &usb_dev->dev;
393         u32 tkid;
394         __le32 tkid_le;
395         struct usb_handshake *hs;
396         struct aes_ccm_nonce ccm_n;
397         u8 mic[8];
398         struct wusb_keydvt_in keydvt_in;
399         struct wusb_keydvt_out keydvt_out;
400
401         hs = kzalloc(3*sizeof(hs[0]), GFP_KERNEL);
402         if (hs == NULL) {
403                 dev_err(dev, "can't allocate handshake data\n");
404                 goto error_kzalloc;
405         }
406
407         /* We need to turn encryption before beginning the 4way
408          * hshake (WUSB1.0[.3.2.2]) */
409         result = wusb_dev_set_encryption(usb_dev, 1);
410         if (result < 0)
411                 goto error_dev_set_encryption;
412
413         tkid = wusbhc_next_tkid(wusbhc, wusb_dev);
414         tkid_le = cpu_to_le32(tkid);
415
416         hs[0].bMessageNumber = 1;
417         hs[0].bStatus = 0;
418         memcpy(hs[0].tTKID, &tkid_le, sizeof(hs[0].tTKID));
419         hs[0].bReserved = 0;
420         memcpy(hs[0].CDID, &wusb_dev->cdid, sizeof(hs[0].CDID));
421         get_random_bytes(&hs[0].nonce, sizeof(hs[0].nonce));
422         memset(hs[0].MIC, 0, sizeof(hs[0].MIC));        /* Per WUSB1.0[T7-22] */
423
424         d_printf(1, dev, "I: sending hs1:\n");
425         hs_printk(2, dev, &hs[0]);
426
427         result = usb_control_msg(
428                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
429                 USB_REQ_SET_HANDSHAKE,
430                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
431                 1, 0, &hs[0], sizeof(hs[0]), 1000 /* FIXME: arbitrary */);
432         if (result < 0) {
433                 dev_err(dev, "Handshake1: request failed: %d\n", result);
434                 goto error_hs1;
435         }
436
437         /* Handshake 2, from the device -- need to verify fields */
438         result = usb_control_msg(
439                 usb_dev, usb_rcvctrlpipe(usb_dev, 0),
440                 USB_REQ_GET_HANDSHAKE,
441                 USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
442                 2, 0, &hs[1], sizeof(hs[1]), 1000 /* FIXME: arbitrary */);
443         if (result < 0) {
444                 dev_err(dev, "Handshake2: request failed: %d\n", result);
445                 goto error_hs2;
446         }
447         d_printf(1, dev, "got HS2:\n");
448         hs_printk(2, dev, &hs[1]);
449
450         result = -EINVAL;
451         if (hs[1].bMessageNumber != 2) {
452                 dev_err(dev, "Handshake2 failed: bad message number %u\n",
453                         hs[1].bMessageNumber);
454                 goto error_hs2;
455         }
456         if (hs[1].bStatus != 0) {
457                 dev_err(dev, "Handshake2 failed: bad status %u\n",
458                         hs[1].bStatus);
459                 goto error_hs2;
460         }
461         if (memcmp(hs[0].tTKID, hs[1].tTKID, sizeof(hs[0].tTKID))) {
462                 dev_err(dev, "Handshake2 failed: TKID mismatch "
463                         "(#1 0x%02x%02x%02x vs #2 0x%02x%02x%02x)\n",
464                         hs[0].tTKID[0], hs[0].tTKID[1], hs[0].tTKID[2],
465                         hs[1].tTKID[0], hs[1].tTKID[1], hs[1].tTKID[2]);
466                 goto error_hs2;
467         }
468         if (memcmp(hs[0].CDID, hs[1].CDID, sizeof(hs[0].CDID))) {
469                 dev_err(dev, "Handshake2 failed: CDID mismatch\n");
470                 goto error_hs2;
471         }
472
473         /* Setup the CCM nonce */
474         memset(&ccm_n.sfn, 0, sizeof(ccm_n.sfn));       /* Per WUSB1.0[6.5.2] */
475         memcpy(ccm_n.tkid, &tkid_le, sizeof(ccm_n.tkid));
476         ccm_n.src_addr = wusbhc->uwb_rc->uwb_dev.dev_addr;
477         ccm_n.dest_addr.data[0] = wusb_dev->addr;
478         ccm_n.dest_addr.data[1] = 0;
479
480         /* Derive the KCK and PTK from CK, the CCM, H and D nonces */
481         memcpy(keydvt_in.hnonce, hs[0].nonce, sizeof(keydvt_in.hnonce));
482         memcpy(keydvt_in.dnonce, hs[1].nonce, sizeof(keydvt_in.dnonce));
483         result = wusb_key_derive(&keydvt_out, ck->data, &ccm_n, &keydvt_in);
484         if (result < 0) {
485                 dev_err(dev, "Handshake2 failed: cannot derive keys: %d\n",
486                         result);
487                 goto error_hs2;
488         }
489         d_printf(2, dev, "KCK:\n");
490         d_dump(2, dev, keydvt_out.kck, sizeof(keydvt_out.kck));
491         d_printf(2, dev, "PTK:\n");
492         d_dump(2, dev, keydvt_out.ptk, sizeof(keydvt_out.ptk));
493
494         /* Compute MIC and verify it */
495         result = wusb_oob_mic(mic, keydvt_out.kck, &ccm_n, &hs[1]);
496         if (result < 0) {
497                 dev_err(dev, "Handshake2 failed: cannot compute MIC: %d\n",
498                         result);
499                 goto error_hs2;
500         }
501
502         d_printf(2, dev, "MIC:\n");
503         d_dump(2, dev, mic, sizeof(mic));
504         if (memcmp(hs[1].MIC, mic, sizeof(hs[1].MIC))) {
505                 dev_err(dev, "Handshake2 failed: MIC mismatch\n");
506                 goto error_hs2;
507         }
508
509         /* Send Handshake3 */
510         hs[2].bMessageNumber = 3;
511         hs[2].bStatus = 0;
512         memcpy(hs[2].tTKID, &tkid_le, sizeof(hs[2].tTKID));
513         hs[2].bReserved = 0;
514         memcpy(hs[2].CDID, &wusb_dev->cdid, sizeof(hs[2].CDID));
515         memcpy(hs[2].nonce, hs[0].nonce, sizeof(hs[2].nonce));
516         result = wusb_oob_mic(hs[2].MIC, keydvt_out.kck, &ccm_n, &hs[2]);
517         if (result < 0) {
518                 dev_err(dev, "Handshake3 failed: cannot compute MIC: %d\n",
519                         result);
520                 goto error_hs2;
521         }
522
523         d_printf(1, dev, "I: sending hs3:\n");
524         hs_printk(2, dev, &hs[2]);
525
526         result = usb_control_msg(
527                 usb_dev, usb_sndctrlpipe(usb_dev, 0),
528                 USB_REQ_SET_HANDSHAKE,
529                 USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
530                 3, 0, &hs[2], sizeof(hs[2]), 1000 /* FIXME: arbitrary */);
531         if (result < 0) {
532                 dev_err(dev, "Handshake3: request failed: %d\n", result);
533                 goto error_hs3;
534         }
535
536         d_printf(1, dev, "I: turning on encryption on host for device\n");
537         d_dump(2, dev, keydvt_out.ptk, sizeof(keydvt_out.ptk));
538         result = wusbhc->set_ptk(wusbhc, wusb_dev->port_idx, tkid,
539                                  keydvt_out.ptk, sizeof(keydvt_out.ptk));
540         if (result < 0)
541                 goto error_wusbhc_set_ptk;
542
543         d_printf(1, dev, "I: setting a GTK\n");
544         result = wusb_dev_set_gtk(wusbhc, wusb_dev);
545         if (result < 0) {
546                 dev_err(dev, "Set GTK for device: request failed: %d\n",
547                         result);
548                 goto error_wusbhc_set_gtk;
549         }
550
551         /* Update the device's address from unauth to auth */
552         if (usb_dev->authenticated == 0) {
553                 d_printf(1, dev, "I: updating addres to auth from non-auth\n");
554                 result = wusb_dev_update_address(wusbhc, wusb_dev);
555                 if (result < 0)
556                         goto error_dev_update_address;
557         }
558         result = 0;
559         d_printf(1, dev, "I: 4way handshke done, device authenticated\n");
560
561 error_dev_update_address:
562 error_wusbhc_set_gtk:
563 error_wusbhc_set_ptk:
564 error_hs3:
565 error_hs2:
566 error_hs1:
567         memset(hs, 0, 3*sizeof(hs[0]));
568         memset(&keydvt_out, 0, sizeof(keydvt_out));
569         memset(&keydvt_in, 0, sizeof(keydvt_in));
570         memset(&ccm_n, 0, sizeof(ccm_n));
571         memset(mic, 0, sizeof(mic));
572         if (result < 0) {
573                 /* error path */
574                 wusb_dev_set_encryption(usb_dev, 0);
575         }
576 error_dev_set_encryption:
577         kfree(hs);
578 error_kzalloc:
579         return result;
580 }
581
582 /*
583  * Once all connected and authenticated devices have received the new
584  * GTK, switch the host to using it.
585  */
586 static void wusbhc_gtk_rekey_done_work(struct work_struct *work)
587 {
588         struct wusbhc *wusbhc = container_of(work, struct wusbhc, gtk_rekey_done_work);
589         size_t key_size = sizeof(wusbhc->gtk.data);
590
591         mutex_lock(&wusbhc->mutex);
592
593         if (--wusbhc->pending_set_gtks == 0)
594                 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
595
596         mutex_unlock(&wusbhc->mutex);
597 }
598
599 static void wusbhc_set_gtk_callback(struct urb *urb)
600 {
601         struct wusbhc *wusbhc = urb->context;
602
603         queue_work(wusbd, &wusbhc->gtk_rekey_done_work);
604 }
605
606 /**
607  * wusbhc_gtk_rekey - generate and distribute a new GTK
608  * @wusbhc: the WUSB host controller
609  *
610  * Generate a new GTK and distribute it to all connected and
611  * authenticated devices.  When all devices have the new GTK, the host
612  * starts using it.
613  *
614  * This must be called after every device disconnect (see [WUSB]
615  * section 6.2.11.2).
616  */
617 void wusbhc_gtk_rekey(struct wusbhc *wusbhc)
618 {
619         static const size_t key_size = sizeof(wusbhc->gtk.data);
620         int p;
621
622         wusbhc_generate_gtk(wusbhc);
623
624         for (p = 0; p < wusbhc->ports_max; p++) {
625                 struct wusb_dev *wusb_dev;
626
627                 wusb_dev = wusbhc->port[p].wusb_dev;
628                 if (!wusb_dev || !wusb_dev->usb_dev | !wusb_dev->usb_dev->authenticated)
629                         continue;
630
631                 usb_fill_control_urb(wusb_dev->set_gtk_urb, wusb_dev->usb_dev,
632                                      usb_sndctrlpipe(wusb_dev->usb_dev, 0),
633                                      (void *)wusb_dev->set_gtk_req,
634                                      &wusbhc->gtk.descr, wusbhc->gtk.descr.bLength,
635                                      wusbhc_set_gtk_callback, wusbhc);
636                 if (usb_submit_urb(wusb_dev->set_gtk_urb, GFP_KERNEL) == 0)
637                         wusbhc->pending_set_gtks++;
638         }
639         if (wusbhc->pending_set_gtks == 0)
640                 wusbhc->set_gtk(wusbhc, wusbhc->gtk_tkid, &wusbhc->gtk.descr.bKeyData, key_size);
641 }