blob: b9af4885ae53e4c60852133d38ab347edadfafca [file] [log] [blame]
Anderson Brigliaeb492e02011-06-09 18:50:40 -03001/*
2 BlueZ - Bluetooth protocol stack for Linux
3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
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 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17
18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
20 SOFTWARE IS DISCLAIMED.
21*/
22
23#include <net/bluetooth/bluetooth.h>
24#include <net/bluetooth/hci_core.h>
25#include <net/bluetooth/l2cap.h>
26#include <net/bluetooth/smp.h>
Anderson Brigliad22ef0b2011-06-09 18:50:44 -030027#include <linux/crypto.h>
Stephen Rothwellf70490e2011-06-23 12:58:55 +100028#include <linux/scatterlist.h>
Anderson Brigliad22ef0b2011-06-09 18:50:44 -030029#include <crypto/b128ops.h>
30
Vinicius Costa Gomes5d3de7d2011-06-14 13:37:41 -030031#define SMP_TIMEOUT 30000 /* 30 seconds */
32
Anderson Brigliad22ef0b2011-06-09 18:50:44 -030033static inline void swap128(u8 src[16], u8 dst[16])
34{
35 int i;
36 for (i = 0; i < 16; i++)
37 dst[15 - i] = src[i];
38}
39
40static inline void swap56(u8 src[7], u8 dst[7])
41{
42 int i;
43 for (i = 0; i < 7; i++)
44 dst[6 - i] = src[i];
45}
46
47static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r)
48{
49 struct blkcipher_desc desc;
50 struct scatterlist sg;
51 int err, iv_len;
52 unsigned char iv[128];
53
54 if (tfm == NULL) {
55 BT_ERR("tfm %p", tfm);
56 return -EINVAL;
57 }
58
59 desc.tfm = tfm;
60 desc.flags = 0;
61
62 err = crypto_blkcipher_setkey(tfm, k, 16);
63 if (err) {
64 BT_ERR("cipher setkey failed: %d", err);
65 return err;
66 }
67
68 sg_init_one(&sg, r, 16);
69
70 iv_len = crypto_blkcipher_ivsize(tfm);
71 if (iv_len) {
72 memset(&iv, 0xff, iv_len);
73 crypto_blkcipher_set_iv(tfm, iv, iv_len);
74 }
75
76 err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16);
77 if (err)
78 BT_ERR("Encrypt data error %d", err);
79
80 return err;
81}
82
83static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16],
84 u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia,
85 u8 _rat, bdaddr_t *ra, u8 res[16])
86{
87 u8 p1[16], p2[16];
88 int err;
89
90 memset(p1, 0, 16);
91
92 /* p1 = pres || preq || _rat || _iat */
93 swap56(pres, p1);
94 swap56(preq, p1 + 7);
95 p1[14] = _rat;
96 p1[15] = _iat;
97
98 memset(p2, 0, 16);
99
100 /* p2 = padding || ia || ra */
101 baswap((bdaddr_t *) (p2 + 4), ia);
102 baswap((bdaddr_t *) (p2 + 10), ra);
103
104 /* res = r XOR p1 */
105 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1);
106
107 /* res = e(k, res) */
108 err = smp_e(tfm, k, res);
109 if (err) {
110 BT_ERR("Encrypt data error");
111 return err;
112 }
113
114 /* res = res XOR p2 */
115 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2);
116
117 /* res = e(k, res) */
118 err = smp_e(tfm, k, res);
119 if (err)
120 BT_ERR("Encrypt data error");
121
122 return err;
123}
124
125static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16],
126 u8 r1[16], u8 r2[16], u8 _r[16])
127{
128 int err;
129
130 /* Just least significant octets from r1 and r2 are considered */
131 memcpy(_r, r1 + 8, 8);
132 memcpy(_r + 8, r2 + 8, 8);
133
134 err = smp_e(tfm, k, _r);
135 if (err)
136 BT_ERR("Encrypt data error");
137
138 return err;
139}
140
141static int smp_rand(u8 *buf)
142{
143 get_random_bytes(buf, 16);
144
145 return 0;
146}
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300147
148static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code,
149 u16 dlen, void *data)
150{
151 struct sk_buff *skb;
152 struct l2cap_hdr *lh;
153 int len;
154
155 len = L2CAP_HDR_SIZE + sizeof(code) + dlen;
156
157 if (len > conn->mtu)
158 return NULL;
159
160 skb = bt_skb_alloc(len, GFP_ATOMIC);
161 if (!skb)
162 return NULL;
163
164 lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
165 lh->len = cpu_to_le16(sizeof(code) + dlen);
166 lh->cid = cpu_to_le16(L2CAP_CID_SMP);
167
168 memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code));
169
170 memcpy(skb_put(skb, dlen), data, dlen);
171
172 return skb;
173}
174
175static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data)
176{
177 struct sk_buff *skb = smp_build_cmd(conn, code, len, data);
178
179 BT_DBG("code 0x%2.2x", code);
180
181 if (!skb)
182 return;
183
Luiz Augusto von Dentz73d80de2011-11-02 15:52:01 +0200184 skb->priority = HCI_PRIO_MAX;
185 hci_send_acl(conn->hchan, skb, 0);
Vinicius Costa Gomese2dcd112011-08-19 21:06:50 -0300186
187 mod_timer(&conn->security_timer, jiffies +
188 msecs_to_jiffies(SMP_TIMEOUT));
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300189}
190
Vinicius Costa Gomesb8e66ea2011-06-09 18:50:52 -0300191static void build_pairing_cmd(struct l2cap_conn *conn,
Vinicius Costa Gomes54790f72011-07-07 18:59:38 -0300192 struct smp_cmd_pairing *req,
193 struct smp_cmd_pairing *rsp,
194 __u8 authreq)
Vinicius Costa Gomesb8e66ea2011-06-09 18:50:52 -0300195{
Vinicius Costa Gomes54790f72011-07-07 18:59:38 -0300196 u8 dist_keys;
197
198 dist_keys = 0;
199 if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->flags)) {
Vinicius Costa Gomesca10b5e2011-08-25 20:02:37 -0300200 dist_keys = SMP_DIST_ENC_KEY;
Vinicius Costa Gomes54790f72011-07-07 18:59:38 -0300201 authreq |= SMP_AUTH_BONDING;
202 }
203
204 if (rsp == NULL) {
205 req->io_capability = conn->hcon->io_capability;
206 req->oob_flag = SMP_OOB_NOT_PRESENT;
207 req->max_key_size = SMP_MAX_ENC_KEY_SIZE;
208 req->init_key_dist = dist_keys;
209 req->resp_key_dist = dist_keys;
210 req->auth_req = authreq;
211 return;
212 }
213
214 rsp->io_capability = conn->hcon->io_capability;
215 rsp->oob_flag = SMP_OOB_NOT_PRESENT;
216 rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE;
217 rsp->init_key_dist = req->init_key_dist & dist_keys;
218 rsp->resp_key_dist = req->resp_key_dist & dist_keys;
219 rsp->auth_req = authreq;
Vinicius Costa Gomesb8e66ea2011-06-09 18:50:52 -0300220}
221
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300222static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size)
223{
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300224 struct smp_chan *smp = conn->smp_chan;
225
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300226 if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) ||
227 (max_key_size < SMP_MIN_ENC_KEY_SIZE))
228 return SMP_ENC_KEY_SIZE;
229
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300230 smp->smp_key_size = max_key_size;
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300231
232 return 0;
233}
234
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300235static void confirm_work(struct work_struct *work)
236{
237 struct smp_chan *smp = container_of(work, struct smp_chan, confirm);
238 struct l2cap_conn *conn = smp->conn;
239 struct crypto_blkcipher *tfm;
240 struct smp_cmd_pairing_confirm cp;
241 int ret;
242 u8 res[16], reason;
243
244 BT_DBG("conn %p", conn);
245
246 tfm = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC);
247 if (IS_ERR(tfm)) {
248 reason = SMP_UNSPECIFIED;
249 goto error;
250 }
251
252 smp->tfm = tfm;
253
254 if (conn->hcon->out)
255 ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, 0,
256 conn->src, conn->hcon->dst_type, conn->dst,
257 res);
258 else
259 ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp,
260 conn->hcon->dst_type, conn->dst, 0, conn->src,
261 res);
262 if (ret) {
263 reason = SMP_UNSPECIFIED;
264 goto error;
265 }
266
267 swap128(res, cp.confirm_val);
268 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp);
269
270 return;
271
272error:
273 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason);
274 smp_chan_destroy(conn);
275}
276
277static void random_work(struct work_struct *work)
278{
279 struct smp_chan *smp = container_of(work, struct smp_chan, random);
280 struct l2cap_conn *conn = smp->conn;
281 struct hci_conn *hcon = conn->hcon;
282 struct crypto_blkcipher *tfm = smp->tfm;
283 u8 reason, confirm[16], res[16], key[16];
284 int ret;
285
286 if (IS_ERR_OR_NULL(tfm)) {
287 reason = SMP_UNSPECIFIED;
288 goto error;
289 }
290
291 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
292
293 if (hcon->out)
294 ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp, 0,
295 conn->src, hcon->dst_type, conn->dst,
296 res);
297 else
298 ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp,
299 hcon->dst_type, conn->dst, 0, conn->src,
300 res);
301 if (ret) {
302 reason = SMP_UNSPECIFIED;
303 goto error;
304 }
305
306 swap128(res, confirm);
307
308 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) {
309 BT_ERR("Pairing failed (confirmation values mismatch)");
310 reason = SMP_CONFIRM_FAILED;
311 goto error;
312 }
313
314 if (hcon->out) {
315 u8 stk[16], rand[8];
316 __le16 ediv;
317
318 memset(rand, 0, sizeof(rand));
319 ediv = 0;
320
321 smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, key);
322 swap128(key, stk);
323
324 memset(stk + smp->smp_key_size, 0,
325 SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size);
326
327 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend)) {
328 reason = SMP_UNSPECIFIED;
329 goto error;
330 }
331
332 hci_le_start_enc(hcon, ediv, rand, stk);
333 hcon->enc_key_size = smp->smp_key_size;
334 } else {
335 u8 stk[16], r[16], rand[8];
336 __le16 ediv;
337
338 memset(rand, 0, sizeof(rand));
339 ediv = 0;
340
341 swap128(smp->prnd, r);
342 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r);
343
344 smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, key);
345 swap128(key, stk);
346
347 memset(stk + smp->smp_key_size, 0,
348 SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size);
349
350 hci_add_ltk(hcon->hdev, 0, conn->dst, smp->smp_key_size,
351 ediv, rand, stk);
352 }
353
354 return;
355
356error:
357 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason);
358 smp_chan_destroy(conn);
359}
360
361static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
362{
363 struct smp_chan *smp;
364
365 smp = kzalloc(sizeof(struct smp_chan), GFP_ATOMIC);
366 if (!smp)
367 return NULL;
368
369 INIT_WORK(&smp->confirm, confirm_work);
370 INIT_WORK(&smp->random, random_work);
371
372 smp->conn = conn;
373 conn->smp_chan = smp;
374
375 hci_conn_hold(conn->hcon);
376
377 return smp;
378}
379
380void smp_chan_destroy(struct l2cap_conn *conn)
381{
Brian Gixc8eb9692011-11-23 08:28:35 -0800382 struct smp_chan *smp = conn->smp_chan;
383
384 clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend);
385
386 if (smp->tfm)
387 crypto_free_blkcipher(smp->tfm);
388
389 kfree(smp);
390 conn->smp_chan = NULL;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300391 hci_conn_put(conn->hcon);
392}
393
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300394static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb)
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300395{
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300396 struct smp_cmd_pairing rsp, *req = (void *) skb->data;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300397 struct smp_chan *smp;
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300398 u8 key_size;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300399 int ret;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300400
401 BT_DBG("conn %p", conn);
402
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300403 if (!test_and_set_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend))
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300404 smp = smp_chan_create(conn);
405
406 smp = conn->smp_chan;
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300407
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300408 smp->preq[0] = SMP_CMD_PAIRING_REQ;
409 memcpy(&smp->preq[1], req, sizeof(*req));
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300410 skb_pull(skb, sizeof(*req));
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300411
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300412 if (req->oob_flag)
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300413 return SMP_OOB_NOT_AVAIL;
414
415 /* We didn't start the pairing, so no requirements */
Vinicius Costa Gomes54790f72011-07-07 18:59:38 -0300416 build_pairing_cmd(conn, req, &rsp, SMP_AUTH_NONE);
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300417
418 key_size = min(req->max_key_size, rsp.max_key_size);
419 if (check_enc_key_size(conn, key_size))
420 return SMP_ENC_KEY_SIZE;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300421
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300422 /* Just works */
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300423 memset(smp->tk, 0, sizeof(smp->tk));
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300424
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300425 ret = smp_rand(smp->prnd);
426 if (ret)
427 return SMP_UNSPECIFIED;
428
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300429 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
430 memcpy(&smp->prsp[1], &rsp, sizeof(rsp));
Anderson Brigliaf01ead32011-06-09 18:50:45 -0300431
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300432 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp);
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300433
434 return 0;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300435}
436
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300437static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb)
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300438{
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300439 struct smp_cmd_pairing *req, *rsp = (void *) skb->data;
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300440 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300441 struct hci_dev *hdev = conn->hcon->hdev;
442 u8 key_size;
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300443 int ret;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300444
445 BT_DBG("conn %p", conn);
446
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300447 skb_pull(skb, sizeof(*rsp));
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300448
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300449 req = (void *) &smp->preq[1];
Vinicius Costa Gomes3158c502011-06-14 13:37:42 -0300450
451 key_size = min(req->max_key_size, rsp->max_key_size);
452 if (check_enc_key_size(conn, key_size))
453 return SMP_ENC_KEY_SIZE;
454
455 if (rsp->oob_flag)
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300456 return SMP_OOB_NOT_AVAIL;
457
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300458 /* Just works */
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300459 memset(smp->tk, 0, sizeof(smp->tk));
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300460
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300461 ret = smp_rand(smp->prnd);
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300462 if (ret)
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300463 return SMP_UNSPECIFIED;
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300464
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300465 smp->prsp[0] = SMP_CMD_PAIRING_RSP;
466 memcpy(&smp->prsp[1], rsp, sizeof(*rsp));
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300467
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300468 queue_work(hdev->workqueue, &smp->confirm);
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300469
470 return 0;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300471}
472
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300473static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb)
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300474{
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300475 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300476 struct hci_dev *hdev = conn->hcon->hdev;
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300477
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300478 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave");
479
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300480 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf));
481 skb_pull(skb, sizeof(smp->pcnf));
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300482
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300483 if (conn->hcon->out) {
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300484 u8 random[16];
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300485
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300486 swap128(smp->prnd, random);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300487 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random),
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300488 random);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300489 } else {
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300490 queue_work(hdev->workqueue, &smp->confirm);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300491 }
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300492
493 return 0;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300494}
495
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300496static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb)
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300497{
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300498 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300499 struct hci_dev *hdev = conn->hcon->hdev;
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300500
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300501 BT_DBG("conn %p", conn);
Anderson Briglia7d24ddc2011-06-09 18:50:46 -0300502
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300503 swap128(skb->data, smp->rrnd);
504 skb_pull(skb, sizeof(smp->rrnd));
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300505
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300506 queue_work(hdev->workqueue, &smp->random);
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300507
508 return 0;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300509}
510
Vinicius Costa Gomes988c5992011-08-25 20:02:28 -0300511static u8 smp_ltk_encrypt(struct l2cap_conn *conn)
512{
513 struct link_key *key;
514 struct key_master_id *master;
515 struct hci_conn *hcon = conn->hcon;
516
517 key = hci_find_link_key_type(hcon->hdev, conn->dst,
518 HCI_LK_SMP_LTK);
519 if (!key)
520 return 0;
521
522 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND,
523 &hcon->pend))
524 return 1;
525
526 master = (void *) key->data;
527 hci_le_start_enc(hcon, master->ediv, master->rand,
528 key->val);
529 hcon->enc_key_size = key->pin_len;
530
531 return 1;
532
533}
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300534static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb)
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300535{
536 struct smp_cmd_security_req *rp = (void *) skb->data;
537 struct smp_cmd_pairing cp;
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300538 struct hci_conn *hcon = conn->hcon;
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300539 struct smp_chan *smp;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300540
541 BT_DBG("conn %p", conn);
542
Vinicius Costa Gomesfeb45eb2011-08-25 20:02:35 -0300543 hcon->pending_sec_level = BT_SECURITY_MEDIUM;
544
Vinicius Costa Gomes988c5992011-08-25 20:02:28 -0300545 if (smp_ltk_encrypt(conn))
546 return 0;
547
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300548 if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend))
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300549 return 0;
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300550
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300551 smp = smp_chan_create(conn);
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300552
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300553 skb_pull(skb, sizeof(*rp));
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300554
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300555 memset(&cp, 0, sizeof(cp));
Vinicius Costa Gomes54790f72011-07-07 18:59:38 -0300556 build_pairing_cmd(conn, &cp, NULL, rp->auth_req);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300557
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300558 smp->preq[0] = SMP_CMD_PAIRING_REQ;
559 memcpy(&smp->preq[1], &cp, sizeof(cp));
Anderson Brigliaf01ead32011-06-09 18:50:45 -0300560
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300561 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300562
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300563 return 0;
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300564}
565
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300566int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level)
567{
Vinicius Costa Gomes3a0259b2011-06-09 18:50:43 -0300568 struct hci_conn *hcon = conn->hcon;
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300569 struct smp_chan *smp = conn->smp_chan;
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300570
Vinicius Costa Gomes3a0259b2011-06-09 18:50:43 -0300571 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level);
572
Andre Guedes2e65c9d2011-06-30 19:20:56 -0300573 if (!lmp_host_le_capable(hcon->hdev))
574 return 1;
575
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300576 if (sec_level == BT_SECURITY_LOW)
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300577 return 1;
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300578
579 if (hcon->sec_level >= sec_level)
580 return 1;
581
Vinicius Costa Gomes988c5992011-08-25 20:02:28 -0300582 if (hcon->link_mode & HCI_LM_MASTER)
583 if (smp_ltk_encrypt(conn))
Vinicius Costa Gomes02bc7452011-07-07 18:59:41 -0300584 goto done;
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300585
586 if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend))
587 return 0;
588
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300589 smp = smp_chan_create(conn);
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300590
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300591 if (hcon->link_mode & HCI_LM_MASTER) {
592 struct smp_cmd_pairing cp;
Anderson Brigliaf01ead32011-06-09 18:50:45 -0300593
Vinicius Costa Gomes0fb4eb62011-08-25 20:02:27 -0300594 build_pairing_cmd(conn, &cp, NULL, SMP_AUTH_NONE);
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300595 smp->preq[0] = SMP_CMD_PAIRING_REQ;
596 memcpy(&smp->preq[1], &cp, sizeof(cp));
Anderson Brigliaf01ead32011-06-09 18:50:45 -0300597
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300598 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp);
599 } else {
600 struct smp_cmd_security_req cp;
Vinicius Costa Gomes0fb4eb62011-08-25 20:02:27 -0300601 cp.auth_req = SMP_AUTH_NONE;
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300602 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp);
603 }
604
Vinicius Costa Gomes02bc7452011-07-07 18:59:41 -0300605done:
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300606 hcon->pending_sec_level = sec_level;
Vinicius Costa Gomesf1cb9af2011-01-26 21:42:57 -0300607
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300608 return 0;
609}
610
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300611static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb)
612{
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300613 struct smp_cmd_encrypt_info *rp = (void *) skb->data;
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300614 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300615
616 skb_pull(skb, sizeof(*rp));
617
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300618 memcpy(smp->tk, rp->ltk, sizeof(smp->tk));
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300619
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300620 return 0;
621}
622
623static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
624{
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300625 struct smp_cmd_master_ident *rp = (void *) skb->data;
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300626 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300627
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300628 skb_pull(skb, sizeof(*rp));
629
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300630 hci_add_ltk(conn->hcon->hdev, 1, conn->src, smp->smp_key_size,
631 rp->ediv, rp->rand, smp->tk);
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300632
633 smp_distribute_keys(conn, 1);
634
635 return 0;
636}
637
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300638int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
639{
640 __u8 code = skb->data[0];
641 __u8 reason;
642 int err = 0;
643
Andre Guedes2e65c9d2011-06-30 19:20:56 -0300644 if (!lmp_host_le_capable(conn->hcon->hdev)) {
645 err = -ENOTSUPP;
646 reason = SMP_PAIRING_NOTSUPP;
647 goto done;
648 }
649
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300650 skb_pull(skb, sizeof(code));
651
652 switch (code) {
653 case SMP_CMD_PAIRING_REQ:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300654 reason = smp_cmd_pairing_req(conn, skb);
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300655 break;
656
657 case SMP_CMD_PAIRING_FAIL:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300658 reason = 0;
659 err = -EPERM;
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300660 break;
661
662 case SMP_CMD_PAIRING_RSP:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300663 reason = smp_cmd_pairing_rsp(conn, skb);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300664 break;
665
666 case SMP_CMD_SECURITY_REQ:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300667 reason = smp_cmd_security_req(conn, skb);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300668 break;
669
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300670 case SMP_CMD_PAIRING_CONFIRM:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300671 reason = smp_cmd_pairing_confirm(conn, skb);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300672 break;
673
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300674 case SMP_CMD_PAIRING_RANDOM:
Vinicius Costa Gomesda85e5e2011-06-09 18:50:53 -0300675 reason = smp_cmd_pairing_random(conn, skb);
Anderson Briglia88ba43b2011-06-09 18:50:42 -0300676 break;
677
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300678 case SMP_CMD_ENCRYPT_INFO:
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300679 reason = smp_cmd_encrypt_info(conn, skb);
680 break;
681
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300682 case SMP_CMD_MASTER_IDENT:
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300683 reason = smp_cmd_master_ident(conn, skb);
684 break;
685
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300686 case SMP_CMD_IDENT_INFO:
687 case SMP_CMD_IDENT_ADDR_INFO:
688 case SMP_CMD_SIGN_INFO:
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300689 /* Just ignored */
690 reason = 0;
691 break;
692
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300693 default:
694 BT_DBG("Unknown command code 0x%2.2x", code);
695
696 reason = SMP_CMD_NOTSUPP;
Vinicius Costa Gomes3a0259b2011-06-09 18:50:43 -0300697 err = -EOPNOTSUPP;
698 goto done;
699 }
700
701done:
702 if (reason)
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300703 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason),
704 &reason);
Anderson Brigliaeb492e02011-06-09 18:50:40 -0300705
706 kfree_skb(skb);
707 return err;
708}
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300709
710int smp_distribute_keys(struct l2cap_conn *conn, __u8 force)
711{
712 struct smp_cmd_pairing *req, *rsp;
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300713 struct smp_chan *smp = conn->smp_chan;
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300714 __u8 *keydist;
715
716 BT_DBG("conn %p force %d", conn, force);
717
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300718 if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend))
719 return 0;
720
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300721 rsp = (void *) &smp->prsp[1];
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300722
723 /* The responder sends its keys first */
724 if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07))
725 return 0;
726
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300727 req = (void *) &smp->preq[1];
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300728
729 if (conn->hcon->out) {
730 keydist = &rsp->init_key_dist;
731 *keydist &= req->init_key_dist;
732 } else {
733 keydist = &rsp->resp_key_dist;
734 *keydist &= req->resp_key_dist;
735 }
736
737
738 BT_DBG("keydist 0x%x", *keydist);
739
740 if (*keydist & SMP_DIST_ENC_KEY) {
741 struct smp_cmd_encrypt_info enc;
742 struct smp_cmd_master_ident ident;
743 __le16 ediv;
744
745 get_random_bytes(enc.ltk, sizeof(enc.ltk));
746 get_random_bytes(&ediv, sizeof(ediv));
747 get_random_bytes(ident.rand, sizeof(ident.rand));
748
749 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc);
750
Vinicius Costa Gomes1c1def02011-09-05 14:31:30 -0300751 hci_add_ltk(conn->hcon->hdev, 1, conn->dst, smp->smp_key_size,
Vinicius Costa Gomes726b4ff2011-07-08 18:31:45 -0300752 ediv, ident.rand, enc.ltk);
Vinicius Costa Gomes16b90832011-07-07 18:59:39 -0300753
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300754 ident.ediv = cpu_to_le16(ediv);
755
756 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident);
757
758 *keydist &= ~SMP_DIST_ENC_KEY;
759 }
760
761 if (*keydist & SMP_DIST_ID_KEY) {
762 struct smp_cmd_ident_addr_info addrinfo;
763 struct smp_cmd_ident_info idinfo;
764
765 /* Send a dummy key */
766 get_random_bytes(idinfo.irk, sizeof(idinfo.irk));
767
768 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo);
769
770 /* Just public address */
771 memset(&addrinfo, 0, sizeof(addrinfo));
772 bacpy(&addrinfo.bdaddr, conn->src);
773
774 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo),
775 &addrinfo);
776
777 *keydist &= ~SMP_DIST_ID_KEY;
778 }
779
780 if (*keydist & SMP_DIST_SIGN) {
781 struct smp_cmd_sign_info sign;
782
783 /* Send a dummy key */
784 get_random_bytes(sign.csrk, sizeof(sign.csrk));
785
786 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign);
787
788 *keydist &= ~SMP_DIST_SIGN;
789 }
790
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300791 if (conn->hcon->out || force) {
792 clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend);
793 del_timer(&conn->security_timer);
Vinicius Costa Gomes8aab4752011-09-05 14:31:31 -0300794 smp_chan_destroy(conn);
Vinicius Costa Gomesd26a2342011-08-19 21:06:51 -0300795 }
796
Vinicius Costa Gomes7034b912011-07-07 18:59:34 -0300797 return 0;
798}