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Commit | Line | Data |
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eb492e01 AB |
1 | /* |
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> | |
d22ef0bc | 27 | #include <linux/crypto.h> |
f70490e6 | 28 | #include <linux/scatterlist.h> |
d22ef0bc AB |
29 | #include <crypto/b128ops.h> |
30 | ||
5d3de7df VCG |
31 | #define SMP_TIMEOUT 30000 /* 30 seconds */ |
32 | ||
d22ef0bc AB |
33 | static 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 | ||
40 | static 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 | ||
47 | static 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 | ||
83 | static 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 | ||
125 | static 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 | ||
141 | static int smp_rand(u8 *buf) | |
142 | { | |
143 | get_random_bytes(buf, 16); | |
144 | ||
145 | return 0; | |
146 | } | |
eb492e01 AB |
147 | |
148 | static 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 | ||
175 | static 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 | ||
184 | hci_send_acl(conn->hcon, skb, 0); | |
e2dcd113 VCG |
185 | |
186 | mod_timer(&conn->security_timer, jiffies + | |
187 | msecs_to_jiffies(SMP_TIMEOUT)); | |
eb492e01 AB |
188 | } |
189 | ||
b8e66eac | 190 | static void build_pairing_cmd(struct l2cap_conn *conn, |
54790f73 VCG |
191 | struct smp_cmd_pairing *req, |
192 | struct smp_cmd_pairing *rsp, | |
193 | __u8 authreq) | |
b8e66eac | 194 | { |
54790f73 VCG |
195 | u8 dist_keys; |
196 | ||
197 | dist_keys = 0; | |
198 | if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->flags)) { | |
199 | dist_keys = SMP_DIST_ENC_KEY | SMP_DIST_ID_KEY | SMP_DIST_SIGN; | |
200 | authreq |= SMP_AUTH_BONDING; | |
201 | } | |
202 | ||
203 | if (rsp == NULL) { | |
204 | req->io_capability = conn->hcon->io_capability; | |
205 | req->oob_flag = SMP_OOB_NOT_PRESENT; | |
206 | req->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
207 | req->init_key_dist = dist_keys; | |
208 | req->resp_key_dist = dist_keys; | |
209 | req->auth_req = authreq; | |
210 | return; | |
211 | } | |
212 | ||
213 | rsp->io_capability = conn->hcon->io_capability; | |
214 | rsp->oob_flag = SMP_OOB_NOT_PRESENT; | |
215 | rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
216 | rsp->init_key_dist = req->init_key_dist & dist_keys; | |
217 | rsp->resp_key_dist = req->resp_key_dist & dist_keys; | |
218 | rsp->auth_req = authreq; | |
b8e66eac VCG |
219 | } |
220 | ||
3158c50c VCG |
221 | static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) |
222 | { | |
1c1def09 VCG |
223 | struct smp_chan *smp = conn->smp_chan; |
224 | ||
3158c50c VCG |
225 | if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || |
226 | (max_key_size < SMP_MIN_ENC_KEY_SIZE)) | |
227 | return SMP_ENC_KEY_SIZE; | |
228 | ||
1c1def09 | 229 | smp->smp_key_size = max_key_size; |
3158c50c VCG |
230 | |
231 | return 0; | |
232 | } | |
233 | ||
8aab4757 VCG |
234 | static void confirm_work(struct work_struct *work) |
235 | { | |
236 | struct smp_chan *smp = container_of(work, struct smp_chan, confirm); | |
237 | struct l2cap_conn *conn = smp->conn; | |
238 | struct crypto_blkcipher *tfm; | |
239 | struct smp_cmd_pairing_confirm cp; | |
240 | int ret; | |
241 | u8 res[16], reason; | |
242 | ||
243 | BT_DBG("conn %p", conn); | |
244 | ||
245 | tfm = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); | |
246 | if (IS_ERR(tfm)) { | |
247 | reason = SMP_UNSPECIFIED; | |
248 | goto error; | |
249 | } | |
250 | ||
251 | smp->tfm = tfm; | |
252 | ||
253 | if (conn->hcon->out) | |
254 | ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, 0, | |
255 | conn->src, conn->hcon->dst_type, conn->dst, | |
256 | res); | |
257 | else | |
258 | ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, | |
259 | conn->hcon->dst_type, conn->dst, 0, conn->src, | |
260 | res); | |
261 | if (ret) { | |
262 | reason = SMP_UNSPECIFIED; | |
263 | goto error; | |
264 | } | |
265 | ||
266 | swap128(res, cp.confirm_val); | |
267 | smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); | |
268 | ||
269 | return; | |
270 | ||
271 | error: | |
272 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason); | |
273 | smp_chan_destroy(conn); | |
274 | } | |
275 | ||
276 | static void random_work(struct work_struct *work) | |
277 | { | |
278 | struct smp_chan *smp = container_of(work, struct smp_chan, random); | |
279 | struct l2cap_conn *conn = smp->conn; | |
280 | struct hci_conn *hcon = conn->hcon; | |
281 | struct crypto_blkcipher *tfm = smp->tfm; | |
282 | u8 reason, confirm[16], res[16], key[16]; | |
283 | int ret; | |
284 | ||
285 | if (IS_ERR_OR_NULL(tfm)) { | |
286 | reason = SMP_UNSPECIFIED; | |
287 | goto error; | |
288 | } | |
289 | ||
290 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); | |
291 | ||
292 | if (hcon->out) | |
293 | ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp, 0, | |
294 | conn->src, hcon->dst_type, conn->dst, | |
295 | res); | |
296 | else | |
297 | ret = smp_c1(tfm, smp->tk, smp->rrnd, smp->preq, smp->prsp, | |
298 | hcon->dst_type, conn->dst, 0, conn->src, | |
299 | res); | |
300 | if (ret) { | |
301 | reason = SMP_UNSPECIFIED; | |
302 | goto error; | |
303 | } | |
304 | ||
305 | swap128(res, confirm); | |
306 | ||
307 | if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) { | |
308 | BT_ERR("Pairing failed (confirmation values mismatch)"); | |
309 | reason = SMP_CONFIRM_FAILED; | |
310 | goto error; | |
311 | } | |
312 | ||
313 | if (hcon->out) { | |
314 | u8 stk[16], rand[8]; | |
315 | __le16 ediv; | |
316 | ||
317 | memset(rand, 0, sizeof(rand)); | |
318 | ediv = 0; | |
319 | ||
320 | smp_s1(tfm, smp->tk, smp->rrnd, smp->prnd, key); | |
321 | swap128(key, stk); | |
322 | ||
323 | memset(stk + smp->smp_key_size, 0, | |
324 | SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); | |
325 | ||
326 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend)) { | |
327 | reason = SMP_UNSPECIFIED; | |
328 | goto error; | |
329 | } | |
330 | ||
331 | hci_le_start_enc(hcon, ediv, rand, stk); | |
332 | hcon->enc_key_size = smp->smp_key_size; | |
333 | } else { | |
334 | u8 stk[16], r[16], rand[8]; | |
335 | __le16 ediv; | |
336 | ||
337 | memset(rand, 0, sizeof(rand)); | |
338 | ediv = 0; | |
339 | ||
340 | swap128(smp->prnd, r); | |
341 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r); | |
342 | ||
343 | smp_s1(tfm, smp->tk, smp->prnd, smp->rrnd, key); | |
344 | swap128(key, stk); | |
345 | ||
346 | memset(stk + smp->smp_key_size, 0, | |
347 | SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); | |
348 | ||
349 | hci_add_ltk(hcon->hdev, 0, conn->dst, smp->smp_key_size, | |
350 | ediv, rand, stk); | |
351 | } | |
352 | ||
353 | return; | |
354 | ||
355 | error: | |
356 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), &reason); | |
357 | smp_chan_destroy(conn); | |
358 | } | |
359 | ||
360 | static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) | |
361 | { | |
362 | struct smp_chan *smp; | |
363 | ||
364 | smp = kzalloc(sizeof(struct smp_chan), GFP_ATOMIC); | |
365 | if (!smp) | |
366 | return NULL; | |
367 | ||
368 | INIT_WORK(&smp->confirm, confirm_work); | |
369 | INIT_WORK(&smp->random, random_work); | |
370 | ||
371 | smp->conn = conn; | |
372 | conn->smp_chan = smp; | |
373 | ||
374 | hci_conn_hold(conn->hcon); | |
375 | ||
376 | return smp; | |
377 | } | |
378 | ||
379 | void smp_chan_destroy(struct l2cap_conn *conn) | |
380 | { | |
381 | kfree(conn->smp_chan); | |
382 | hci_conn_put(conn->hcon); | |
383 | } | |
384 | ||
da85e5e5 | 385 | static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 386 | { |
3158c50c | 387 | struct smp_cmd_pairing rsp, *req = (void *) skb->data; |
8aab4757 | 388 | struct smp_chan *smp; |
3158c50c | 389 | u8 key_size; |
8aab4757 | 390 | int ret; |
88ba43b6 AB |
391 | |
392 | BT_DBG("conn %p", conn); | |
393 | ||
d26a2345 | 394 | if (!test_and_set_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
8aab4757 VCG |
395 | smp = smp_chan_create(conn); |
396 | ||
397 | smp = conn->smp_chan; | |
d26a2345 | 398 | |
1c1def09 VCG |
399 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
400 | memcpy(&smp->preq[1], req, sizeof(*req)); | |
3158c50c | 401 | skb_pull(skb, sizeof(*req)); |
88ba43b6 | 402 | |
3158c50c | 403 | if (req->oob_flag) |
da85e5e5 VCG |
404 | return SMP_OOB_NOT_AVAIL; |
405 | ||
406 | /* We didn't start the pairing, so no requirements */ | |
54790f73 | 407 | build_pairing_cmd(conn, req, &rsp, SMP_AUTH_NONE); |
3158c50c VCG |
408 | |
409 | key_size = min(req->max_key_size, rsp.max_key_size); | |
410 | if (check_enc_key_size(conn, key_size)) | |
411 | return SMP_ENC_KEY_SIZE; | |
88ba43b6 | 412 | |
7d24ddcc | 413 | /* Just works */ |
1c1def09 | 414 | memset(smp->tk, 0, sizeof(smp->tk)); |
7d24ddcc | 415 | |
8aab4757 VCG |
416 | ret = smp_rand(smp->prnd); |
417 | if (ret) | |
418 | return SMP_UNSPECIFIED; | |
419 | ||
1c1def09 VCG |
420 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
421 | memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); | |
f01ead31 | 422 | |
3158c50c | 423 | smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); |
da85e5e5 VCG |
424 | |
425 | return 0; | |
88ba43b6 AB |
426 | } |
427 | ||
da85e5e5 | 428 | static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 429 | { |
3158c50c | 430 | struct smp_cmd_pairing *req, *rsp = (void *) skb->data; |
1c1def09 | 431 | struct smp_chan *smp = conn->smp_chan; |
8aab4757 VCG |
432 | struct hci_dev *hdev = conn->hcon->hdev; |
433 | u8 key_size; | |
7d24ddcc | 434 | int ret; |
88ba43b6 AB |
435 | |
436 | BT_DBG("conn %p", conn); | |
437 | ||
3158c50c VCG |
438 | skb_pull(skb, sizeof(*rsp)); |
439 | ||
1c1def09 | 440 | req = (void *) &smp->preq[1]; |
da85e5e5 | 441 | |
3158c50c VCG |
442 | key_size = min(req->max_key_size, rsp->max_key_size); |
443 | if (check_enc_key_size(conn, key_size)) | |
444 | return SMP_ENC_KEY_SIZE; | |
445 | ||
446 | if (rsp->oob_flag) | |
da85e5e5 VCG |
447 | return SMP_OOB_NOT_AVAIL; |
448 | ||
7d24ddcc | 449 | /* Just works */ |
1c1def09 | 450 | memset(smp->tk, 0, sizeof(smp->tk)); |
88ba43b6 | 451 | |
1c1def09 | 452 | ret = smp_rand(smp->prnd); |
7d24ddcc | 453 | if (ret) |
da85e5e5 | 454 | return SMP_UNSPECIFIED; |
7d24ddcc | 455 | |
8aab4757 VCG |
456 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
457 | memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); | |
7d24ddcc | 458 | |
8aab4757 | 459 | queue_work(hdev->workqueue, &smp->confirm); |
da85e5e5 VCG |
460 | |
461 | return 0; | |
88ba43b6 AB |
462 | } |
463 | ||
da85e5e5 | 464 | static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 465 | { |
1c1def09 | 466 | struct smp_chan *smp = conn->smp_chan; |
8aab4757 | 467 | struct hci_dev *hdev = conn->hcon->hdev; |
7d24ddcc | 468 | |
88ba43b6 AB |
469 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); |
470 | ||
1c1def09 VCG |
471 | memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); |
472 | skb_pull(skb, sizeof(smp->pcnf)); | |
88ba43b6 | 473 | |
7d24ddcc AB |
474 | if (conn->hcon->out) { |
475 | u8 random[16]; | |
88ba43b6 | 476 | |
1c1def09 | 477 | swap128(smp->prnd, random); |
88ba43b6 | 478 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random), |
7d24ddcc | 479 | random); |
88ba43b6 | 480 | } else { |
8aab4757 | 481 | queue_work(hdev->workqueue, &smp->confirm); |
88ba43b6 | 482 | } |
da85e5e5 VCG |
483 | |
484 | return 0; | |
88ba43b6 AB |
485 | } |
486 | ||
da85e5e5 | 487 | static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 488 | { |
1c1def09 | 489 | struct smp_chan *smp = conn->smp_chan; |
8aab4757 | 490 | struct hci_dev *hdev = conn->hcon->hdev; |
7d24ddcc | 491 | |
8aab4757 | 492 | BT_DBG("conn %p", conn); |
3158c50c | 493 | |
8aab4757 VCG |
494 | swap128(skb->data, smp->rrnd); |
495 | skb_pull(skb, sizeof(smp->rrnd)); | |
e7e62c85 | 496 | |
8aab4757 | 497 | queue_work(hdev->workqueue, &smp->random); |
da85e5e5 VCG |
498 | |
499 | return 0; | |
88ba43b6 AB |
500 | } |
501 | ||
da85e5e5 | 502 | static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 AB |
503 | { |
504 | struct smp_cmd_security_req *rp = (void *) skb->data; | |
505 | struct smp_cmd_pairing cp; | |
f1cb9af5 | 506 | struct hci_conn *hcon = conn->hcon; |
8aab4757 | 507 | struct smp_chan *smp; |
88ba43b6 AB |
508 | |
509 | BT_DBG("conn %p", conn); | |
510 | ||
d26a2345 | 511 | if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) |
da85e5e5 | 512 | return 0; |
f1cb9af5 | 513 | |
8aab4757 | 514 | smp = smp_chan_create(conn); |
d26a2345 | 515 | |
88ba43b6 | 516 | skb_pull(skb, sizeof(*rp)); |
88ba43b6 | 517 | |
da85e5e5 | 518 | memset(&cp, 0, sizeof(cp)); |
54790f73 | 519 | build_pairing_cmd(conn, &cp, NULL, rp->auth_req); |
88ba43b6 | 520 | |
1c1def09 VCG |
521 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
522 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 523 | |
88ba43b6 | 524 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
f1cb9af5 | 525 | |
da85e5e5 | 526 | return 0; |
88ba43b6 AB |
527 | } |
528 | ||
eb492e01 AB |
529 | int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level) |
530 | { | |
3a0259bb | 531 | struct hci_conn *hcon = conn->hcon; |
1c1def09 | 532 | struct smp_chan *smp = conn->smp_chan; |
eb492e01 | 533 | |
3a0259bb VCG |
534 | BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); |
535 | ||
2e65c9d2 AG |
536 | if (!lmp_host_le_capable(hcon->hdev)) |
537 | return 1; | |
538 | ||
f1cb9af5 VCG |
539 | if (sec_level == BT_SECURITY_LOW) |
540 | return 1; | |
eb492e01 | 541 | |
f1cb9af5 | 542 | if (hcon->sec_level >= sec_level) |
eb492e01 | 543 | return 1; |
f1cb9af5 | 544 | |
3a0259bb | 545 | if (hcon->link_mode & HCI_LM_MASTER) { |
02bc7455 VCG |
546 | struct link_key *key; |
547 | ||
548 | key = hci_find_link_key_type(hcon->hdev, conn->dst, | |
549 | HCI_LK_SMP_LTK); | |
550 | if (key) { | |
551 | struct key_master_id *master = (void *) key->data; | |
552 | ||
d26a2345 VCG |
553 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, |
554 | &hcon->pend)) | |
555 | goto done; | |
556 | ||
02bc7455 VCG |
557 | hci_le_start_enc(hcon, master->ediv, master->rand, |
558 | key->val); | |
726b4ffc VCG |
559 | hcon->enc_key_size = key->pin_len; |
560 | ||
02bc7455 VCG |
561 | goto done; |
562 | } | |
d26a2345 VCG |
563 | } |
564 | ||
565 | if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) | |
566 | return 0; | |
567 | ||
8aab4757 | 568 | smp = smp_chan_create(conn); |
d26a2345 | 569 | |
d26a2345 VCG |
570 | if (hcon->link_mode & HCI_LM_MASTER) { |
571 | struct smp_cmd_pairing cp; | |
f01ead31 | 572 | |
0fb4eb6f | 573 | build_pairing_cmd(conn, &cp, NULL, SMP_AUTH_NONE); |
1c1def09 VCG |
574 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
575 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 576 | |
eb492e01 AB |
577 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
578 | } else { | |
579 | struct smp_cmd_security_req cp; | |
0fb4eb6f | 580 | cp.auth_req = SMP_AUTH_NONE; |
eb492e01 AB |
581 | smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); |
582 | } | |
583 | ||
02bc7455 | 584 | done: |
f1cb9af5 | 585 | hcon->pending_sec_level = sec_level; |
f1cb9af5 | 586 | |
eb492e01 AB |
587 | return 0; |
588 | } | |
589 | ||
7034b911 VCG |
590 | static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) |
591 | { | |
16b90839 | 592 | struct smp_cmd_encrypt_info *rp = (void *) skb->data; |
1c1def09 | 593 | struct smp_chan *smp = conn->smp_chan; |
16b90839 VCG |
594 | |
595 | skb_pull(skb, sizeof(*rp)); | |
596 | ||
1c1def09 | 597 | memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); |
16b90839 | 598 | |
7034b911 VCG |
599 | return 0; |
600 | } | |
601 | ||
602 | static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) | |
603 | { | |
16b90839 | 604 | struct smp_cmd_master_ident *rp = (void *) skb->data; |
1c1def09 | 605 | struct smp_chan *smp = conn->smp_chan; |
16b90839 VCG |
606 | |
607 | skb_pull(skb, sizeof(*rp)); | |
7034b911 | 608 | |
1c1def09 VCG |
609 | hci_add_ltk(conn->hcon->hdev, 1, conn->src, smp->smp_key_size, |
610 | rp->ediv, rp->rand, smp->tk); | |
7034b911 VCG |
611 | |
612 | smp_distribute_keys(conn, 1); | |
613 | ||
614 | return 0; | |
615 | } | |
616 | ||
eb492e01 AB |
617 | int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb) |
618 | { | |
619 | __u8 code = skb->data[0]; | |
620 | __u8 reason; | |
621 | int err = 0; | |
622 | ||
2e65c9d2 AG |
623 | if (!lmp_host_le_capable(conn->hcon->hdev)) { |
624 | err = -ENOTSUPP; | |
625 | reason = SMP_PAIRING_NOTSUPP; | |
626 | goto done; | |
627 | } | |
628 | ||
eb492e01 AB |
629 | skb_pull(skb, sizeof(code)); |
630 | ||
631 | switch (code) { | |
632 | case SMP_CMD_PAIRING_REQ: | |
da85e5e5 | 633 | reason = smp_cmd_pairing_req(conn, skb); |
eb492e01 AB |
634 | break; |
635 | ||
636 | case SMP_CMD_PAIRING_FAIL: | |
da85e5e5 VCG |
637 | reason = 0; |
638 | err = -EPERM; | |
eb492e01 AB |
639 | break; |
640 | ||
641 | case SMP_CMD_PAIRING_RSP: | |
da85e5e5 | 642 | reason = smp_cmd_pairing_rsp(conn, skb); |
88ba43b6 AB |
643 | break; |
644 | ||
645 | case SMP_CMD_SECURITY_REQ: | |
da85e5e5 | 646 | reason = smp_cmd_security_req(conn, skb); |
88ba43b6 AB |
647 | break; |
648 | ||
eb492e01 | 649 | case SMP_CMD_PAIRING_CONFIRM: |
da85e5e5 | 650 | reason = smp_cmd_pairing_confirm(conn, skb); |
88ba43b6 AB |
651 | break; |
652 | ||
eb492e01 | 653 | case SMP_CMD_PAIRING_RANDOM: |
da85e5e5 | 654 | reason = smp_cmd_pairing_random(conn, skb); |
88ba43b6 AB |
655 | break; |
656 | ||
eb492e01 | 657 | case SMP_CMD_ENCRYPT_INFO: |
7034b911 VCG |
658 | reason = smp_cmd_encrypt_info(conn, skb); |
659 | break; | |
660 | ||
eb492e01 | 661 | case SMP_CMD_MASTER_IDENT: |
7034b911 VCG |
662 | reason = smp_cmd_master_ident(conn, skb); |
663 | break; | |
664 | ||
eb492e01 AB |
665 | case SMP_CMD_IDENT_INFO: |
666 | case SMP_CMD_IDENT_ADDR_INFO: | |
667 | case SMP_CMD_SIGN_INFO: | |
7034b911 VCG |
668 | /* Just ignored */ |
669 | reason = 0; | |
670 | break; | |
671 | ||
eb492e01 AB |
672 | default: |
673 | BT_DBG("Unknown command code 0x%2.2x", code); | |
674 | ||
675 | reason = SMP_CMD_NOTSUPP; | |
eb492e01 | 676 | err = -EOPNOTSUPP; |
3a0259bb | 677 | goto done; |
eb492e01 AB |
678 | } |
679 | ||
3a0259bb VCG |
680 | done: |
681 | if (reason) | |
682 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), | |
683 | &reason); | |
684 | ||
eb492e01 AB |
685 | kfree_skb(skb); |
686 | return err; | |
687 | } | |
7034b911 VCG |
688 | |
689 | int smp_distribute_keys(struct l2cap_conn *conn, __u8 force) | |
690 | { | |
691 | struct smp_cmd_pairing *req, *rsp; | |
1c1def09 | 692 | struct smp_chan *smp = conn->smp_chan; |
7034b911 VCG |
693 | __u8 *keydist; |
694 | ||
695 | BT_DBG("conn %p force %d", conn, force); | |
696 | ||
d26a2345 VCG |
697 | if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
698 | return 0; | |
699 | ||
1c1def09 | 700 | rsp = (void *) &smp->prsp[1]; |
7034b911 VCG |
701 | |
702 | /* The responder sends its keys first */ | |
703 | if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07)) | |
704 | return 0; | |
705 | ||
1c1def09 | 706 | req = (void *) &smp->preq[1]; |
7034b911 VCG |
707 | |
708 | if (conn->hcon->out) { | |
709 | keydist = &rsp->init_key_dist; | |
710 | *keydist &= req->init_key_dist; | |
711 | } else { | |
712 | keydist = &rsp->resp_key_dist; | |
713 | *keydist &= req->resp_key_dist; | |
714 | } | |
715 | ||
716 | ||
717 | BT_DBG("keydist 0x%x", *keydist); | |
718 | ||
719 | if (*keydist & SMP_DIST_ENC_KEY) { | |
720 | struct smp_cmd_encrypt_info enc; | |
721 | struct smp_cmd_master_ident ident; | |
722 | __le16 ediv; | |
723 | ||
724 | get_random_bytes(enc.ltk, sizeof(enc.ltk)); | |
725 | get_random_bytes(&ediv, sizeof(ediv)); | |
726 | get_random_bytes(ident.rand, sizeof(ident.rand)); | |
727 | ||
728 | smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); | |
729 | ||
1c1def09 | 730 | hci_add_ltk(conn->hcon->hdev, 1, conn->dst, smp->smp_key_size, |
726b4ffc | 731 | ediv, ident.rand, enc.ltk); |
16b90839 | 732 | |
7034b911 VCG |
733 | ident.ediv = cpu_to_le16(ediv); |
734 | ||
735 | smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); | |
736 | ||
737 | *keydist &= ~SMP_DIST_ENC_KEY; | |
738 | } | |
739 | ||
740 | if (*keydist & SMP_DIST_ID_KEY) { | |
741 | struct smp_cmd_ident_addr_info addrinfo; | |
742 | struct smp_cmd_ident_info idinfo; | |
743 | ||
744 | /* Send a dummy key */ | |
745 | get_random_bytes(idinfo.irk, sizeof(idinfo.irk)); | |
746 | ||
747 | smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); | |
748 | ||
749 | /* Just public address */ | |
750 | memset(&addrinfo, 0, sizeof(addrinfo)); | |
751 | bacpy(&addrinfo.bdaddr, conn->src); | |
752 | ||
753 | smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), | |
754 | &addrinfo); | |
755 | ||
756 | *keydist &= ~SMP_DIST_ID_KEY; | |
757 | } | |
758 | ||
759 | if (*keydist & SMP_DIST_SIGN) { | |
760 | struct smp_cmd_sign_info sign; | |
761 | ||
762 | /* Send a dummy key */ | |
763 | get_random_bytes(sign.csrk, sizeof(sign.csrk)); | |
764 | ||
765 | smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); | |
766 | ||
767 | *keydist &= ~SMP_DIST_SIGN; | |
768 | } | |
769 | ||
d26a2345 VCG |
770 | if (conn->hcon->out || force) { |
771 | clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend); | |
772 | del_timer(&conn->security_timer); | |
8aab4757 | 773 | smp_chan_destroy(conn); |
d26a2345 VCG |
774 | } |
775 | ||
7034b911 VCG |
776 | return 0; |
777 | } |