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 | ||
8c520a59 GP |
23 | #include <linux/crypto.h> |
24 | #include <linux/scatterlist.h> | |
25 | #include <crypto/b128ops.h> | |
26 | ||
eb492e01 AB |
27 | #include <net/bluetooth/bluetooth.h> |
28 | #include <net/bluetooth/hci_core.h> | |
29 | #include <net/bluetooth/l2cap.h> | |
2b64d153 | 30 | #include <net/bluetooth/mgmt.h> |
ac4b7236 MH |
31 | |
32 | #include "smp.h" | |
d22ef0bc | 33 | |
b28b4943 | 34 | #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) |
b28b4943 | 35 | |
17b02e62 | 36 | #define SMP_TIMEOUT msecs_to_jiffies(30000) |
5d3de7df | 37 | |
0edb14de JH |
38 | #define AUTH_REQ_MASK(dev) (test_bit(HCI_SC_ENABLED, &(dev)->dev_flags) ? \ |
39 | 0x1f : 0x07) | |
40 | #define KEY_DIST_MASK 0x07 | |
065a13e2 | 41 | |
533e35d4 JH |
42 | enum { |
43 | SMP_FLAG_TK_VALID, | |
44 | SMP_FLAG_CFM_PENDING, | |
45 | SMP_FLAG_MITM_AUTH, | |
46 | SMP_FLAG_COMPLETE, | |
47 | SMP_FLAG_INITIATOR, | |
65668776 | 48 | SMP_FLAG_SC, |
533e35d4 | 49 | }; |
4bc58f51 JH |
50 | |
51 | struct smp_chan { | |
b68fda68 JH |
52 | struct l2cap_conn *conn; |
53 | struct delayed_work security_timer; | |
b28b4943 | 54 | unsigned long allow_cmd; /* Bitmask of allowed commands */ |
b68fda68 | 55 | |
4bc58f51 JH |
56 | u8 preq[7]; /* SMP Pairing Request */ |
57 | u8 prsp[7]; /* SMP Pairing Response */ | |
58 | u8 prnd[16]; /* SMP Pairing Random (local) */ | |
59 | u8 rrnd[16]; /* SMP Pairing Random (remote) */ | |
60 | u8 pcnf[16]; /* SMP Pairing Confirm */ | |
61 | u8 tk[16]; /* SMP Temporary Key */ | |
62 | u8 enc_key_size; | |
63 | u8 remote_key_dist; | |
64 | bdaddr_t id_addr; | |
65 | u8 id_addr_type; | |
66 | u8 irk[16]; | |
67 | struct smp_csrk *csrk; | |
68 | struct smp_csrk *slave_csrk; | |
69 | struct smp_ltk *ltk; | |
70 | struct smp_ltk *slave_ltk; | |
71 | struct smp_irk *remote_irk; | |
4a74d658 | 72 | unsigned long flags; |
6a7bd103 JH |
73 | |
74 | struct crypto_blkcipher *tfm_aes; | |
4bc58f51 JH |
75 | }; |
76 | ||
8a2936f4 | 77 | static inline void swap_buf(const u8 *src, u8 *dst, size_t len) |
d22ef0bc | 78 | { |
8a2936f4 | 79 | size_t i; |
d22ef0bc | 80 | |
8a2936f4 JH |
81 | for (i = 0; i < len; i++) |
82 | dst[len - 1 - i] = src[i]; | |
d22ef0bc AB |
83 | } |
84 | ||
85 | static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) | |
86 | { | |
87 | struct blkcipher_desc desc; | |
88 | struct scatterlist sg; | |
943a732a | 89 | uint8_t tmp[16], data[16]; |
201a5929 | 90 | int err; |
d22ef0bc AB |
91 | |
92 | if (tfm == NULL) { | |
93 | BT_ERR("tfm %p", tfm); | |
94 | return -EINVAL; | |
95 | } | |
96 | ||
97 | desc.tfm = tfm; | |
98 | desc.flags = 0; | |
99 | ||
943a732a | 100 | /* The most significant octet of key corresponds to k[0] */ |
8a2936f4 | 101 | swap_buf(k, tmp, 16); |
943a732a JH |
102 | |
103 | err = crypto_blkcipher_setkey(tfm, tmp, 16); | |
d22ef0bc AB |
104 | if (err) { |
105 | BT_ERR("cipher setkey failed: %d", err); | |
106 | return err; | |
107 | } | |
108 | ||
943a732a | 109 | /* Most significant octet of plaintextData corresponds to data[0] */ |
8a2936f4 | 110 | swap_buf(r, data, 16); |
943a732a JH |
111 | |
112 | sg_init_one(&sg, data, 16); | |
d22ef0bc | 113 | |
d22ef0bc AB |
114 | err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16); |
115 | if (err) | |
116 | BT_ERR("Encrypt data error %d", err); | |
117 | ||
943a732a | 118 | /* Most significant octet of encryptedData corresponds to data[0] */ |
8a2936f4 | 119 | swap_buf(data, r, 16); |
943a732a | 120 | |
d22ef0bc AB |
121 | return err; |
122 | } | |
123 | ||
60478054 JH |
124 | static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3]) |
125 | { | |
943a732a | 126 | u8 _res[16]; |
60478054 JH |
127 | int err; |
128 | ||
129 | /* r' = padding || r */ | |
943a732a JH |
130 | memcpy(_res, r, 3); |
131 | memset(_res + 3, 0, 13); | |
60478054 | 132 | |
943a732a | 133 | err = smp_e(tfm, irk, _res); |
60478054 JH |
134 | if (err) { |
135 | BT_ERR("Encrypt error"); | |
136 | return err; | |
137 | } | |
138 | ||
139 | /* The output of the random address function ah is: | |
140 | * ah(h, r) = e(k, r') mod 2^24 | |
141 | * The output of the security function e is then truncated to 24 bits | |
142 | * by taking the least significant 24 bits of the output of e as the | |
143 | * result of ah. | |
144 | */ | |
943a732a | 145 | memcpy(res, _res, 3); |
60478054 JH |
146 | |
147 | return 0; | |
148 | } | |
149 | ||
defce9e8 | 150 | bool smp_irk_matches(struct hci_dev *hdev, u8 irk[16], bdaddr_t *bdaddr) |
60478054 | 151 | { |
defce9e8 JH |
152 | struct l2cap_chan *chan = hdev->smp_data; |
153 | struct crypto_blkcipher *tfm; | |
60478054 JH |
154 | u8 hash[3]; |
155 | int err; | |
156 | ||
defce9e8 JH |
157 | if (!chan || !chan->data) |
158 | return false; | |
159 | ||
160 | tfm = chan->data; | |
161 | ||
60478054 JH |
162 | BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk); |
163 | ||
164 | err = smp_ah(tfm, irk, &bdaddr->b[3], hash); | |
165 | if (err) | |
166 | return false; | |
167 | ||
168 | return !memcmp(bdaddr->b, hash, 3); | |
169 | } | |
170 | ||
defce9e8 | 171 | int smp_generate_rpa(struct hci_dev *hdev, u8 irk[16], bdaddr_t *rpa) |
b1e2b3ae | 172 | { |
defce9e8 JH |
173 | struct l2cap_chan *chan = hdev->smp_data; |
174 | struct crypto_blkcipher *tfm; | |
b1e2b3ae JH |
175 | int err; |
176 | ||
defce9e8 JH |
177 | if (!chan || !chan->data) |
178 | return -EOPNOTSUPP; | |
179 | ||
180 | tfm = chan->data; | |
181 | ||
b1e2b3ae JH |
182 | get_random_bytes(&rpa->b[3], 3); |
183 | ||
184 | rpa->b[5] &= 0x3f; /* Clear two most significant bits */ | |
185 | rpa->b[5] |= 0x40; /* Set second most significant bit */ | |
186 | ||
187 | err = smp_ah(tfm, irk, &rpa->b[3], rpa->b); | |
188 | if (err < 0) | |
189 | return err; | |
190 | ||
191 | BT_DBG("RPA %pMR", rpa); | |
192 | ||
193 | return 0; | |
194 | } | |
195 | ||
e491eaf3 JH |
196 | static int smp_c1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r[16], |
197 | u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia, u8 _rat, | |
198 | bdaddr_t *ra, u8 res[16]) | |
d22ef0bc AB |
199 | { |
200 | u8 p1[16], p2[16]; | |
201 | int err; | |
202 | ||
203 | memset(p1, 0, 16); | |
204 | ||
205 | /* p1 = pres || preq || _rat || _iat */ | |
943a732a JH |
206 | p1[0] = _iat; |
207 | p1[1] = _rat; | |
208 | memcpy(p1 + 2, preq, 7); | |
209 | memcpy(p1 + 9, pres, 7); | |
d22ef0bc AB |
210 | |
211 | /* p2 = padding || ia || ra */ | |
943a732a JH |
212 | memcpy(p2, ra, 6); |
213 | memcpy(p2 + 6, ia, 6); | |
214 | memset(p2 + 12, 0, 4); | |
d22ef0bc AB |
215 | |
216 | /* res = r XOR p1 */ | |
217 | u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); | |
218 | ||
219 | /* res = e(k, res) */ | |
e491eaf3 | 220 | err = smp_e(tfm_aes, k, res); |
d22ef0bc AB |
221 | if (err) { |
222 | BT_ERR("Encrypt data error"); | |
223 | return err; | |
224 | } | |
225 | ||
226 | /* res = res XOR p2 */ | |
227 | u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); | |
228 | ||
229 | /* res = e(k, res) */ | |
e491eaf3 | 230 | err = smp_e(tfm_aes, k, res); |
d22ef0bc AB |
231 | if (err) |
232 | BT_ERR("Encrypt data error"); | |
233 | ||
234 | return err; | |
235 | } | |
236 | ||
e491eaf3 JH |
237 | static int smp_s1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r1[16], |
238 | u8 r2[16], u8 _r[16]) | |
d22ef0bc AB |
239 | { |
240 | int err; | |
241 | ||
242 | /* Just least significant octets from r1 and r2 are considered */ | |
943a732a JH |
243 | memcpy(_r, r2, 8); |
244 | memcpy(_r + 8, r1, 8); | |
d22ef0bc | 245 | |
e491eaf3 | 246 | err = smp_e(tfm_aes, k, _r); |
d22ef0bc AB |
247 | if (err) |
248 | BT_ERR("Encrypt data error"); | |
249 | ||
250 | return err; | |
251 | } | |
252 | ||
5d88cc73 | 253 | static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) |
eb492e01 | 254 | { |
5d88cc73 | 255 | struct l2cap_chan *chan = conn->smp; |
b68fda68 | 256 | struct smp_chan *smp; |
5d88cc73 JH |
257 | struct kvec iv[2]; |
258 | struct msghdr msg; | |
eb492e01 | 259 | |
5d88cc73 JH |
260 | if (!chan) |
261 | return; | |
eb492e01 | 262 | |
5d88cc73 | 263 | BT_DBG("code 0x%2.2x", code); |
eb492e01 | 264 | |
5d88cc73 JH |
265 | iv[0].iov_base = &code; |
266 | iv[0].iov_len = 1; | |
eb492e01 | 267 | |
5d88cc73 JH |
268 | iv[1].iov_base = data; |
269 | iv[1].iov_len = len; | |
eb492e01 | 270 | |
5d88cc73 | 271 | memset(&msg, 0, sizeof(msg)); |
eb492e01 | 272 | |
5d88cc73 JH |
273 | msg.msg_iov = (struct iovec *) &iv; |
274 | msg.msg_iovlen = 2; | |
eb492e01 | 275 | |
5d88cc73 | 276 | l2cap_chan_send(chan, &msg, 1 + len); |
e2dcd113 | 277 | |
b68fda68 JH |
278 | if (!chan->data) |
279 | return; | |
280 | ||
281 | smp = chan->data; | |
282 | ||
283 | cancel_delayed_work_sync(&smp->security_timer); | |
1b0921d6 | 284 | schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); |
eb492e01 AB |
285 | } |
286 | ||
d2eb9e10 | 287 | static u8 authreq_to_seclevel(u8 authreq) |
2b64d153 | 288 | { |
d2eb9e10 JH |
289 | if (authreq & SMP_AUTH_MITM) { |
290 | if (authreq & SMP_AUTH_SC) | |
291 | return BT_SECURITY_FIPS; | |
292 | else | |
293 | return BT_SECURITY_HIGH; | |
294 | } else { | |
2b64d153 | 295 | return BT_SECURITY_MEDIUM; |
d2eb9e10 | 296 | } |
2b64d153 BG |
297 | } |
298 | ||
299 | static __u8 seclevel_to_authreq(__u8 sec_level) | |
300 | { | |
301 | switch (sec_level) { | |
d2eb9e10 | 302 | case BT_SECURITY_FIPS: |
2b64d153 BG |
303 | case BT_SECURITY_HIGH: |
304 | return SMP_AUTH_MITM | SMP_AUTH_BONDING; | |
305 | case BT_SECURITY_MEDIUM: | |
306 | return SMP_AUTH_BONDING; | |
307 | default: | |
308 | return SMP_AUTH_NONE; | |
309 | } | |
310 | } | |
311 | ||
b8e66eac | 312 | static void build_pairing_cmd(struct l2cap_conn *conn, |
f1560463 MH |
313 | struct smp_cmd_pairing *req, |
314 | struct smp_cmd_pairing *rsp, __u8 authreq) | |
b8e66eac | 315 | { |
5d88cc73 JH |
316 | struct l2cap_chan *chan = conn->smp; |
317 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
318 | struct hci_conn *hcon = conn->hcon; |
319 | struct hci_dev *hdev = hcon->hdev; | |
320 | u8 local_dist = 0, remote_dist = 0; | |
54790f73 | 321 | |
b6ae8457 | 322 | if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) { |
7ee4ea36 MH |
323 | local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; |
324 | remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; | |
54790f73 | 325 | authreq |= SMP_AUTH_BONDING; |
2b64d153 BG |
326 | } else { |
327 | authreq &= ~SMP_AUTH_BONDING; | |
54790f73 VCG |
328 | } |
329 | ||
fd349c02 JH |
330 | if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags)) |
331 | remote_dist |= SMP_DIST_ID_KEY; | |
332 | ||
863efaf2 JH |
333 | if (test_bit(HCI_PRIVACY, &hdev->dev_flags)) |
334 | local_dist |= SMP_DIST_ID_KEY; | |
335 | ||
df8e1a4c JH |
336 | if (test_bit(HCI_SC_ENABLED, &hdev->dev_flags)) { |
337 | if ((authreq & SMP_AUTH_SC) && | |
338 | test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) { | |
339 | local_dist |= SMP_DIST_LINK_KEY; | |
340 | remote_dist |= SMP_DIST_LINK_KEY; | |
341 | } | |
342 | } else { | |
343 | authreq &= ~SMP_AUTH_SC; | |
344 | } | |
345 | ||
54790f73 VCG |
346 | if (rsp == NULL) { |
347 | req->io_capability = conn->hcon->io_capability; | |
348 | req->oob_flag = SMP_OOB_NOT_PRESENT; | |
349 | req->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
fd349c02 JH |
350 | req->init_key_dist = local_dist; |
351 | req->resp_key_dist = remote_dist; | |
0edb14de | 352 | req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); |
fd349c02 JH |
353 | |
354 | smp->remote_key_dist = remote_dist; | |
54790f73 VCG |
355 | return; |
356 | } | |
357 | ||
358 | rsp->io_capability = conn->hcon->io_capability; | |
359 | rsp->oob_flag = SMP_OOB_NOT_PRESENT; | |
360 | rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
fd349c02 JH |
361 | rsp->init_key_dist = req->init_key_dist & remote_dist; |
362 | rsp->resp_key_dist = req->resp_key_dist & local_dist; | |
0edb14de | 363 | rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); |
fd349c02 JH |
364 | |
365 | smp->remote_key_dist = rsp->init_key_dist; | |
b8e66eac VCG |
366 | } |
367 | ||
3158c50c VCG |
368 | static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) |
369 | { | |
5d88cc73 JH |
370 | struct l2cap_chan *chan = conn->smp; |
371 | struct smp_chan *smp = chan->data; | |
1c1def09 | 372 | |
3158c50c | 373 | if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || |
f1560463 | 374 | (max_key_size < SMP_MIN_ENC_KEY_SIZE)) |
3158c50c VCG |
375 | return SMP_ENC_KEY_SIZE; |
376 | ||
f7aa611a | 377 | smp->enc_key_size = max_key_size; |
3158c50c VCG |
378 | |
379 | return 0; | |
380 | } | |
381 | ||
6f48e260 JH |
382 | static void smp_chan_destroy(struct l2cap_conn *conn) |
383 | { | |
384 | struct l2cap_chan *chan = conn->smp; | |
385 | struct smp_chan *smp = chan->data; | |
386 | bool complete; | |
387 | ||
388 | BUG_ON(!smp); | |
389 | ||
390 | cancel_delayed_work_sync(&smp->security_timer); | |
6f48e260 | 391 | |
6f48e260 JH |
392 | complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); |
393 | mgmt_smp_complete(conn->hcon, complete); | |
394 | ||
395 | kfree(smp->csrk); | |
396 | kfree(smp->slave_csrk); | |
397 | ||
398 | crypto_free_blkcipher(smp->tfm_aes); | |
399 | ||
400 | /* If pairing failed clean up any keys we might have */ | |
401 | if (!complete) { | |
402 | if (smp->ltk) { | |
970d0f1b JH |
403 | list_del_rcu(&smp->ltk->list); |
404 | kfree_rcu(smp->ltk, rcu); | |
6f48e260 JH |
405 | } |
406 | ||
407 | if (smp->slave_ltk) { | |
970d0f1b JH |
408 | list_del_rcu(&smp->slave_ltk->list); |
409 | kfree_rcu(smp->slave_ltk, rcu); | |
6f48e260 JH |
410 | } |
411 | ||
412 | if (smp->remote_irk) { | |
adae20cb JH |
413 | list_del_rcu(&smp->remote_irk->list); |
414 | kfree_rcu(smp->remote_irk, rcu); | |
6f48e260 JH |
415 | } |
416 | } | |
417 | ||
418 | chan->data = NULL; | |
419 | kfree(smp); | |
420 | hci_conn_drop(conn->hcon); | |
421 | } | |
422 | ||
84794e11 | 423 | static void smp_failure(struct l2cap_conn *conn, u8 reason) |
4f957a76 | 424 | { |
bab73cb6 | 425 | struct hci_conn *hcon = conn->hcon; |
b68fda68 | 426 | struct l2cap_chan *chan = conn->smp; |
bab73cb6 | 427 | |
84794e11 | 428 | if (reason) |
4f957a76 | 429 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), |
f1560463 | 430 | &reason); |
4f957a76 | 431 | |
ce39fb4e | 432 | clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags); |
e1e930f5 | 433 | mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); |
f1c09c07 | 434 | |
fc75cc86 | 435 | if (chan->data) |
f1c09c07 | 436 | smp_chan_destroy(conn); |
4f957a76 BG |
437 | } |
438 | ||
2b64d153 BG |
439 | #define JUST_WORKS 0x00 |
440 | #define JUST_CFM 0x01 | |
441 | #define REQ_PASSKEY 0x02 | |
442 | #define CFM_PASSKEY 0x03 | |
443 | #define REQ_OOB 0x04 | |
444 | #define OVERLAP 0xFF | |
445 | ||
446 | static const u8 gen_method[5][5] = { | |
447 | { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, | |
448 | { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, | |
449 | { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, | |
450 | { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, | |
451 | { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, | |
452 | }; | |
453 | ||
581370cc JH |
454 | static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) |
455 | { | |
2bcd4003 JH |
456 | /* If either side has unknown io_caps, use JUST_CFM (which gets |
457 | * converted later to JUST_WORKS if we're initiators. | |
458 | */ | |
581370cc JH |
459 | if (local_io > SMP_IO_KEYBOARD_DISPLAY || |
460 | remote_io > SMP_IO_KEYBOARD_DISPLAY) | |
2bcd4003 | 461 | return JUST_CFM; |
581370cc JH |
462 | |
463 | return gen_method[remote_io][local_io]; | |
464 | } | |
465 | ||
2b64d153 BG |
466 | static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, |
467 | u8 local_io, u8 remote_io) | |
468 | { | |
469 | struct hci_conn *hcon = conn->hcon; | |
5d88cc73 JH |
470 | struct l2cap_chan *chan = conn->smp; |
471 | struct smp_chan *smp = chan->data; | |
2b64d153 BG |
472 | u8 method; |
473 | u32 passkey = 0; | |
474 | int ret = 0; | |
475 | ||
476 | /* Initialize key for JUST WORKS */ | |
477 | memset(smp->tk, 0, sizeof(smp->tk)); | |
4a74d658 | 478 | clear_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
479 | |
480 | BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); | |
481 | ||
2bcd4003 JH |
482 | /* If neither side wants MITM, either "just" confirm an incoming |
483 | * request or use just-works for outgoing ones. The JUST_CFM | |
484 | * will be converted to JUST_WORKS if necessary later in this | |
485 | * function. If either side has MITM look up the method from the | |
486 | * table. | |
487 | */ | |
581370cc | 488 | if (!(auth & SMP_AUTH_MITM)) |
2bcd4003 | 489 | method = JUST_CFM; |
2b64d153 | 490 | else |
581370cc | 491 | method = get_auth_method(smp, local_io, remote_io); |
2b64d153 | 492 | |
a82505c7 | 493 | /* Don't confirm locally initiated pairing attempts */ |
4a74d658 | 494 | if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) |
a82505c7 JH |
495 | method = JUST_WORKS; |
496 | ||
02f3e254 JH |
497 | /* Don't bother user space with no IO capabilities */ |
498 | if (method == JUST_CFM && hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) | |
499 | method = JUST_WORKS; | |
500 | ||
2b64d153 BG |
501 | /* If Just Works, Continue with Zero TK */ |
502 | if (method == JUST_WORKS) { | |
4a74d658 | 503 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
504 | return 0; |
505 | } | |
506 | ||
507 | /* Not Just Works/Confirm results in MITM Authentication */ | |
5eb596f5 | 508 | if (method != JUST_CFM) { |
4a74d658 | 509 | set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); |
5eb596f5 JH |
510 | if (hcon->pending_sec_level < BT_SECURITY_HIGH) |
511 | hcon->pending_sec_level = BT_SECURITY_HIGH; | |
512 | } | |
2b64d153 BG |
513 | |
514 | /* If both devices have Keyoard-Display I/O, the master | |
515 | * Confirms and the slave Enters the passkey. | |
516 | */ | |
517 | if (method == OVERLAP) { | |
40bef302 | 518 | if (hcon->role == HCI_ROLE_MASTER) |
2b64d153 BG |
519 | method = CFM_PASSKEY; |
520 | else | |
521 | method = REQ_PASSKEY; | |
522 | } | |
523 | ||
01ad34d2 | 524 | /* Generate random passkey. */ |
2b64d153 | 525 | if (method == CFM_PASSKEY) { |
943a732a | 526 | memset(smp->tk, 0, sizeof(smp->tk)); |
2b64d153 BG |
527 | get_random_bytes(&passkey, sizeof(passkey)); |
528 | passkey %= 1000000; | |
943a732a | 529 | put_unaligned_le32(passkey, smp->tk); |
2b64d153 | 530 | BT_DBG("PassKey: %d", passkey); |
4a74d658 | 531 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
532 | } |
533 | ||
2b64d153 | 534 | if (method == REQ_PASSKEY) |
ce39fb4e | 535 | ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, |
272d90df | 536 | hcon->type, hcon->dst_type); |
4eb65e66 JH |
537 | else if (method == JUST_CFM) |
538 | ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, | |
539 | hcon->type, hcon->dst_type, | |
540 | passkey, 1); | |
2b64d153 | 541 | else |
01ad34d2 | 542 | ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, |
272d90df | 543 | hcon->type, hcon->dst_type, |
39adbffe | 544 | passkey, 0); |
2b64d153 | 545 | |
2b64d153 BG |
546 | return ret; |
547 | } | |
548 | ||
1cc61144 | 549 | static u8 smp_confirm(struct smp_chan *smp) |
8aab4757 | 550 | { |
8aab4757 | 551 | struct l2cap_conn *conn = smp->conn; |
8aab4757 VCG |
552 | struct smp_cmd_pairing_confirm cp; |
553 | int ret; | |
8aab4757 VCG |
554 | |
555 | BT_DBG("conn %p", conn); | |
556 | ||
e491eaf3 | 557 | ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp, |
b1cd5fd9 | 558 | conn->hcon->init_addr_type, &conn->hcon->init_addr, |
943a732a JH |
559 | conn->hcon->resp_addr_type, &conn->hcon->resp_addr, |
560 | cp.confirm_val); | |
1cc61144 JH |
561 | if (ret) |
562 | return SMP_UNSPECIFIED; | |
8aab4757 | 563 | |
4a74d658 | 564 | clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
2b64d153 | 565 | |
8aab4757 VCG |
566 | smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); |
567 | ||
b28b4943 JH |
568 | if (conn->hcon->out) |
569 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); | |
570 | else | |
571 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); | |
572 | ||
1cc61144 | 573 | return 0; |
8aab4757 VCG |
574 | } |
575 | ||
861580a9 | 576 | static u8 smp_random(struct smp_chan *smp) |
8aab4757 | 577 | { |
8aab4757 VCG |
578 | struct l2cap_conn *conn = smp->conn; |
579 | struct hci_conn *hcon = conn->hcon; | |
861580a9 | 580 | u8 confirm[16]; |
8aab4757 VCG |
581 | int ret; |
582 | ||
ec70f36f | 583 | if (IS_ERR_OR_NULL(smp->tfm_aes)) |
861580a9 | 584 | return SMP_UNSPECIFIED; |
8aab4757 VCG |
585 | |
586 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); | |
587 | ||
e491eaf3 | 588 | ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp, |
b1cd5fd9 | 589 | hcon->init_addr_type, &hcon->init_addr, |
943a732a | 590 | hcon->resp_addr_type, &hcon->resp_addr, confirm); |
861580a9 JH |
591 | if (ret) |
592 | return SMP_UNSPECIFIED; | |
8aab4757 | 593 | |
8aab4757 VCG |
594 | if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) { |
595 | BT_ERR("Pairing failed (confirmation values mismatch)"); | |
861580a9 | 596 | return SMP_CONFIRM_FAILED; |
8aab4757 VCG |
597 | } |
598 | ||
599 | if (hcon->out) { | |
fe39c7b2 MH |
600 | u8 stk[16]; |
601 | __le64 rand = 0; | |
602 | __le16 ediv = 0; | |
8aab4757 | 603 | |
e491eaf3 | 604 | smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk); |
8aab4757 | 605 | |
f7aa611a | 606 | memset(stk + smp->enc_key_size, 0, |
04124681 | 607 | SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); |
8aab4757 | 608 | |
861580a9 JH |
609 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) |
610 | return SMP_UNSPECIFIED; | |
8aab4757 VCG |
611 | |
612 | hci_le_start_enc(hcon, ediv, rand, stk); | |
f7aa611a | 613 | hcon->enc_key_size = smp->enc_key_size; |
fe59a05f | 614 | set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); |
8aab4757 | 615 | } else { |
fff3490f | 616 | u8 stk[16], auth; |
fe39c7b2 MH |
617 | __le64 rand = 0; |
618 | __le16 ediv = 0; | |
8aab4757 | 619 | |
943a732a JH |
620 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), |
621 | smp->prnd); | |
8aab4757 | 622 | |
e491eaf3 | 623 | smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk); |
8aab4757 | 624 | |
f7aa611a | 625 | memset(stk + smp->enc_key_size, 0, |
f1560463 | 626 | SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); |
8aab4757 | 627 | |
fff3490f JH |
628 | if (hcon->pending_sec_level == BT_SECURITY_HIGH) |
629 | auth = 1; | |
630 | else | |
631 | auth = 0; | |
632 | ||
7d5843b7 JH |
633 | /* Even though there's no _SLAVE suffix this is the |
634 | * slave STK we're adding for later lookup (the master | |
635 | * STK never needs to be stored). | |
636 | */ | |
ce39fb4e | 637 | hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, |
2ceba539 | 638 | SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); |
8aab4757 VCG |
639 | } |
640 | ||
861580a9 | 641 | return 0; |
8aab4757 VCG |
642 | } |
643 | ||
44f1a7ab JH |
644 | static void smp_notify_keys(struct l2cap_conn *conn) |
645 | { | |
646 | struct l2cap_chan *chan = conn->smp; | |
647 | struct smp_chan *smp = chan->data; | |
648 | struct hci_conn *hcon = conn->hcon; | |
649 | struct hci_dev *hdev = hcon->hdev; | |
650 | struct smp_cmd_pairing *req = (void *) &smp->preq[1]; | |
651 | struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; | |
652 | bool persistent; | |
653 | ||
654 | if (smp->remote_irk) { | |
655 | mgmt_new_irk(hdev, smp->remote_irk); | |
656 | /* Now that user space can be considered to know the | |
657 | * identity address track the connection based on it | |
658 | * from now on. | |
659 | */ | |
660 | bacpy(&hcon->dst, &smp->remote_irk->bdaddr); | |
661 | hcon->dst_type = smp->remote_irk->addr_type; | |
f3d82d0c | 662 | queue_work(hdev->workqueue, &conn->id_addr_update_work); |
44f1a7ab JH |
663 | |
664 | /* When receiving an indentity resolving key for | |
665 | * a remote device that does not use a resolvable | |
666 | * private address, just remove the key so that | |
667 | * it is possible to use the controller white | |
668 | * list for scanning. | |
669 | * | |
670 | * Userspace will have been told to not store | |
671 | * this key at this point. So it is safe to | |
672 | * just remove it. | |
673 | */ | |
674 | if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) { | |
adae20cb JH |
675 | list_del_rcu(&smp->remote_irk->list); |
676 | kfree_rcu(smp->remote_irk, rcu); | |
44f1a7ab JH |
677 | smp->remote_irk = NULL; |
678 | } | |
679 | } | |
680 | ||
681 | /* The LTKs and CSRKs should be persistent only if both sides | |
682 | * had the bonding bit set in their authentication requests. | |
683 | */ | |
684 | persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING); | |
685 | ||
686 | if (smp->csrk) { | |
687 | smp->csrk->bdaddr_type = hcon->dst_type; | |
688 | bacpy(&smp->csrk->bdaddr, &hcon->dst); | |
689 | mgmt_new_csrk(hdev, smp->csrk, persistent); | |
690 | } | |
691 | ||
692 | if (smp->slave_csrk) { | |
693 | smp->slave_csrk->bdaddr_type = hcon->dst_type; | |
694 | bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); | |
695 | mgmt_new_csrk(hdev, smp->slave_csrk, persistent); | |
696 | } | |
697 | ||
698 | if (smp->ltk) { | |
699 | smp->ltk->bdaddr_type = hcon->dst_type; | |
700 | bacpy(&smp->ltk->bdaddr, &hcon->dst); | |
701 | mgmt_new_ltk(hdev, smp->ltk, persistent); | |
702 | } | |
703 | ||
704 | if (smp->slave_ltk) { | |
705 | smp->slave_ltk->bdaddr_type = hcon->dst_type; | |
706 | bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); | |
707 | mgmt_new_ltk(hdev, smp->slave_ltk, persistent); | |
708 | } | |
709 | } | |
710 | ||
b28b4943 JH |
711 | static void smp_allow_key_dist(struct smp_chan *smp) |
712 | { | |
713 | /* Allow the first expected phase 3 PDU. The rest of the PDUs | |
714 | * will be allowed in each PDU handler to ensure we receive | |
715 | * them in the correct order. | |
716 | */ | |
717 | if (smp->remote_key_dist & SMP_DIST_ENC_KEY) | |
718 | SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); | |
719 | else if (smp->remote_key_dist & SMP_DIST_ID_KEY) | |
720 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); | |
721 | else if (smp->remote_key_dist & SMP_DIST_SIGN) | |
722 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
723 | } | |
724 | ||
d6268e86 | 725 | static void smp_distribute_keys(struct smp_chan *smp) |
44f1a7ab JH |
726 | { |
727 | struct smp_cmd_pairing *req, *rsp; | |
86d1407c | 728 | struct l2cap_conn *conn = smp->conn; |
44f1a7ab JH |
729 | struct hci_conn *hcon = conn->hcon; |
730 | struct hci_dev *hdev = hcon->hdev; | |
731 | __u8 *keydist; | |
732 | ||
733 | BT_DBG("conn %p", conn); | |
734 | ||
44f1a7ab JH |
735 | rsp = (void *) &smp->prsp[1]; |
736 | ||
737 | /* The responder sends its keys first */ | |
b28b4943 JH |
738 | if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { |
739 | smp_allow_key_dist(smp); | |
86d1407c | 740 | return; |
b28b4943 | 741 | } |
44f1a7ab JH |
742 | |
743 | req = (void *) &smp->preq[1]; | |
744 | ||
745 | if (hcon->out) { | |
746 | keydist = &rsp->init_key_dist; | |
747 | *keydist &= req->init_key_dist; | |
748 | } else { | |
749 | keydist = &rsp->resp_key_dist; | |
750 | *keydist &= req->resp_key_dist; | |
751 | } | |
752 | ||
753 | BT_DBG("keydist 0x%x", *keydist); | |
754 | ||
755 | if (*keydist & SMP_DIST_ENC_KEY) { | |
756 | struct smp_cmd_encrypt_info enc; | |
757 | struct smp_cmd_master_ident ident; | |
758 | struct smp_ltk *ltk; | |
759 | u8 authenticated; | |
760 | __le16 ediv; | |
761 | __le64 rand; | |
762 | ||
763 | get_random_bytes(enc.ltk, sizeof(enc.ltk)); | |
764 | get_random_bytes(&ediv, sizeof(ediv)); | |
765 | get_random_bytes(&rand, sizeof(rand)); | |
766 | ||
767 | smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); | |
768 | ||
769 | authenticated = hcon->sec_level == BT_SECURITY_HIGH; | |
770 | ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, | |
771 | SMP_LTK_SLAVE, authenticated, enc.ltk, | |
772 | smp->enc_key_size, ediv, rand); | |
773 | smp->slave_ltk = ltk; | |
774 | ||
775 | ident.ediv = ediv; | |
776 | ident.rand = rand; | |
777 | ||
778 | smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); | |
779 | ||
780 | *keydist &= ~SMP_DIST_ENC_KEY; | |
781 | } | |
782 | ||
783 | if (*keydist & SMP_DIST_ID_KEY) { | |
784 | struct smp_cmd_ident_addr_info addrinfo; | |
785 | struct smp_cmd_ident_info idinfo; | |
786 | ||
787 | memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); | |
788 | ||
789 | smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); | |
790 | ||
791 | /* The hci_conn contains the local identity address | |
792 | * after the connection has been established. | |
793 | * | |
794 | * This is true even when the connection has been | |
795 | * established using a resolvable random address. | |
796 | */ | |
797 | bacpy(&addrinfo.bdaddr, &hcon->src); | |
798 | addrinfo.addr_type = hcon->src_type; | |
799 | ||
800 | smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), | |
801 | &addrinfo); | |
802 | ||
803 | *keydist &= ~SMP_DIST_ID_KEY; | |
804 | } | |
805 | ||
806 | if (*keydist & SMP_DIST_SIGN) { | |
807 | struct smp_cmd_sign_info sign; | |
808 | struct smp_csrk *csrk; | |
809 | ||
810 | /* Generate a new random key */ | |
811 | get_random_bytes(sign.csrk, sizeof(sign.csrk)); | |
812 | ||
813 | csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); | |
814 | if (csrk) { | |
815 | csrk->master = 0x00; | |
816 | memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); | |
817 | } | |
818 | smp->slave_csrk = csrk; | |
819 | ||
820 | smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); | |
821 | ||
822 | *keydist &= ~SMP_DIST_SIGN; | |
823 | } | |
824 | ||
825 | /* If there are still keys to be received wait for them */ | |
b28b4943 JH |
826 | if (smp->remote_key_dist & KEY_DIST_MASK) { |
827 | smp_allow_key_dist(smp); | |
86d1407c | 828 | return; |
b28b4943 | 829 | } |
44f1a7ab | 830 | |
44f1a7ab JH |
831 | set_bit(SMP_FLAG_COMPLETE, &smp->flags); |
832 | smp_notify_keys(conn); | |
833 | ||
834 | smp_chan_destroy(conn); | |
44f1a7ab JH |
835 | } |
836 | ||
b68fda68 JH |
837 | static void smp_timeout(struct work_struct *work) |
838 | { | |
839 | struct smp_chan *smp = container_of(work, struct smp_chan, | |
840 | security_timer.work); | |
841 | struct l2cap_conn *conn = smp->conn; | |
842 | ||
843 | BT_DBG("conn %p", conn); | |
844 | ||
1e91c29e | 845 | hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); |
b68fda68 JH |
846 | } |
847 | ||
8aab4757 VCG |
848 | static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) |
849 | { | |
5d88cc73 | 850 | struct l2cap_chan *chan = conn->smp; |
8aab4757 VCG |
851 | struct smp_chan *smp; |
852 | ||
f1560463 | 853 | smp = kzalloc(sizeof(*smp), GFP_ATOMIC); |
fc75cc86 | 854 | if (!smp) |
8aab4757 VCG |
855 | return NULL; |
856 | ||
6a7bd103 JH |
857 | smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); |
858 | if (IS_ERR(smp->tfm_aes)) { | |
859 | BT_ERR("Unable to create ECB crypto context"); | |
860 | kfree(smp); | |
861 | return NULL; | |
862 | } | |
863 | ||
8aab4757 | 864 | smp->conn = conn; |
5d88cc73 | 865 | chan->data = smp; |
8aab4757 | 866 | |
b28b4943 JH |
867 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); |
868 | ||
b68fda68 JH |
869 | INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); |
870 | ||
8aab4757 VCG |
871 | hci_conn_hold(conn->hcon); |
872 | ||
873 | return smp; | |
874 | } | |
875 | ||
2b64d153 BG |
876 | int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) |
877 | { | |
b10e8017 | 878 | struct l2cap_conn *conn = hcon->l2cap_data; |
5d88cc73 | 879 | struct l2cap_chan *chan; |
2b64d153 BG |
880 | struct smp_chan *smp; |
881 | u32 value; | |
fc75cc86 | 882 | int err; |
2b64d153 BG |
883 | |
884 | BT_DBG(""); | |
885 | ||
fc75cc86 | 886 | if (!conn) |
2b64d153 BG |
887 | return -ENOTCONN; |
888 | ||
5d88cc73 JH |
889 | chan = conn->smp; |
890 | if (!chan) | |
891 | return -ENOTCONN; | |
892 | ||
fc75cc86 JH |
893 | l2cap_chan_lock(chan); |
894 | if (!chan->data) { | |
895 | err = -ENOTCONN; | |
896 | goto unlock; | |
897 | } | |
898 | ||
5d88cc73 | 899 | smp = chan->data; |
2b64d153 BG |
900 | |
901 | switch (mgmt_op) { | |
902 | case MGMT_OP_USER_PASSKEY_REPLY: | |
903 | value = le32_to_cpu(passkey); | |
943a732a | 904 | memset(smp->tk, 0, sizeof(smp->tk)); |
2b64d153 | 905 | BT_DBG("PassKey: %d", value); |
943a732a | 906 | put_unaligned_le32(value, smp->tk); |
2b64d153 BG |
907 | /* Fall Through */ |
908 | case MGMT_OP_USER_CONFIRM_REPLY: | |
4a74d658 | 909 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
910 | break; |
911 | case MGMT_OP_USER_PASSKEY_NEG_REPLY: | |
912 | case MGMT_OP_USER_CONFIRM_NEG_REPLY: | |
84794e11 | 913 | smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); |
fc75cc86 JH |
914 | err = 0; |
915 | goto unlock; | |
2b64d153 | 916 | default: |
84794e11 | 917 | smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); |
fc75cc86 JH |
918 | err = -EOPNOTSUPP; |
919 | goto unlock; | |
2b64d153 BG |
920 | } |
921 | ||
fc75cc86 JH |
922 | err = 0; |
923 | ||
2b64d153 | 924 | /* If it is our turn to send Pairing Confirm, do so now */ |
1cc61144 JH |
925 | if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { |
926 | u8 rsp = smp_confirm(smp); | |
927 | if (rsp) | |
928 | smp_failure(conn, rsp); | |
929 | } | |
2b64d153 | 930 | |
fc75cc86 JH |
931 | unlock: |
932 | l2cap_chan_unlock(chan); | |
933 | return err; | |
2b64d153 BG |
934 | } |
935 | ||
da85e5e5 | 936 | static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 937 | { |
3158c50c | 938 | struct smp_cmd_pairing rsp, *req = (void *) skb->data; |
fc75cc86 | 939 | struct l2cap_chan *chan = conn->smp; |
b3c6410b | 940 | struct hci_dev *hdev = conn->hcon->hdev; |
8aab4757 | 941 | struct smp_chan *smp; |
c7262e71 | 942 | u8 key_size, auth, sec_level; |
8aab4757 | 943 | int ret; |
88ba43b6 AB |
944 | |
945 | BT_DBG("conn %p", conn); | |
946 | ||
c46b98be | 947 | if (skb->len < sizeof(*req)) |
38e4a915 | 948 | return SMP_INVALID_PARAMS; |
c46b98be | 949 | |
40bef302 | 950 | if (conn->hcon->role != HCI_ROLE_SLAVE) |
2b64d153 BG |
951 | return SMP_CMD_NOTSUPP; |
952 | ||
fc75cc86 | 953 | if (!chan->data) |
8aab4757 | 954 | smp = smp_chan_create(conn); |
fc75cc86 | 955 | else |
5d88cc73 | 956 | smp = chan->data; |
8aab4757 | 957 | |
d08fd0e7 AE |
958 | if (!smp) |
959 | return SMP_UNSPECIFIED; | |
d26a2345 | 960 | |
c05b9339 | 961 | /* We didn't start the pairing, so match remote */ |
0edb14de | 962 | auth = req->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 963 | |
b6ae8457 | 964 | if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) && |
c05b9339 | 965 | (auth & SMP_AUTH_BONDING)) |
b3c6410b JH |
966 | return SMP_PAIRING_NOTSUPP; |
967 | ||
1c1def09 VCG |
968 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
969 | memcpy(&smp->preq[1], req, sizeof(*req)); | |
3158c50c | 970 | skb_pull(skb, sizeof(*req)); |
88ba43b6 | 971 | |
5be5e275 | 972 | if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) |
1afc2a1a JH |
973 | sec_level = BT_SECURITY_MEDIUM; |
974 | else | |
975 | sec_level = authreq_to_seclevel(auth); | |
976 | ||
c7262e71 JH |
977 | if (sec_level > conn->hcon->pending_sec_level) |
978 | conn->hcon->pending_sec_level = sec_level; | |
fdde0a26 | 979 | |
49c922bb | 980 | /* If we need MITM check that it can be achieved */ |
2ed8f65c JH |
981 | if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { |
982 | u8 method; | |
983 | ||
984 | method = get_auth_method(smp, conn->hcon->io_capability, | |
985 | req->io_capability); | |
986 | if (method == JUST_WORKS || method == JUST_CFM) | |
987 | return SMP_AUTH_REQUIREMENTS; | |
988 | } | |
989 | ||
2b64d153 | 990 | build_pairing_cmd(conn, req, &rsp, auth); |
3158c50c | 991 | |
65668776 JH |
992 | if (rsp.auth_req & SMP_AUTH_SC) |
993 | set_bit(SMP_FLAG_SC, &smp->flags); | |
994 | ||
3158c50c VCG |
995 | key_size = min(req->max_key_size, rsp.max_key_size); |
996 | if (check_enc_key_size(conn, key_size)) | |
997 | return SMP_ENC_KEY_SIZE; | |
88ba43b6 | 998 | |
e84a6b13 | 999 | get_random_bytes(smp->prnd, sizeof(smp->prnd)); |
8aab4757 | 1000 | |
1c1def09 VCG |
1001 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
1002 | memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); | |
f01ead31 | 1003 | |
3158c50c | 1004 | smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); |
b28b4943 | 1005 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); |
da85e5e5 | 1006 | |
2b64d153 BG |
1007 | /* Request setup of TK */ |
1008 | ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); | |
1009 | if (ret) | |
1010 | return SMP_UNSPECIFIED; | |
1011 | ||
da85e5e5 | 1012 | return 0; |
88ba43b6 AB |
1013 | } |
1014 | ||
da85e5e5 | 1015 | static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1016 | { |
3158c50c | 1017 | struct smp_cmd_pairing *req, *rsp = (void *) skb->data; |
5d88cc73 JH |
1018 | struct l2cap_chan *chan = conn->smp; |
1019 | struct smp_chan *smp = chan->data; | |
0edb14de | 1020 | struct hci_dev *hdev = conn->hcon->hdev; |
3a7dbfb8 | 1021 | u8 key_size, auth; |
7d24ddcc | 1022 | int ret; |
88ba43b6 AB |
1023 | |
1024 | BT_DBG("conn %p", conn); | |
1025 | ||
c46b98be | 1026 | if (skb->len < sizeof(*rsp)) |
38e4a915 | 1027 | return SMP_INVALID_PARAMS; |
c46b98be | 1028 | |
40bef302 | 1029 | if (conn->hcon->role != HCI_ROLE_MASTER) |
2b64d153 BG |
1030 | return SMP_CMD_NOTSUPP; |
1031 | ||
3158c50c VCG |
1032 | skb_pull(skb, sizeof(*rsp)); |
1033 | ||
1c1def09 | 1034 | req = (void *) &smp->preq[1]; |
da85e5e5 | 1035 | |
3158c50c VCG |
1036 | key_size = min(req->max_key_size, rsp->max_key_size); |
1037 | if (check_enc_key_size(conn, key_size)) | |
1038 | return SMP_ENC_KEY_SIZE; | |
1039 | ||
0edb14de | 1040 | auth = rsp->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 1041 | |
65668776 JH |
1042 | if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) |
1043 | set_bit(SMP_FLAG_SC, &smp->flags); | |
d2eb9e10 JH |
1044 | else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) |
1045 | conn->hcon->pending_sec_level = BT_SECURITY_HIGH; | |
65668776 | 1046 | |
49c922bb | 1047 | /* If we need MITM check that it can be achieved */ |
2ed8f65c JH |
1048 | if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { |
1049 | u8 method; | |
1050 | ||
1051 | method = get_auth_method(smp, req->io_capability, | |
1052 | rsp->io_capability); | |
1053 | if (method == JUST_WORKS || method == JUST_CFM) | |
1054 | return SMP_AUTH_REQUIREMENTS; | |
1055 | } | |
1056 | ||
e84a6b13 | 1057 | get_random_bytes(smp->prnd, sizeof(smp->prnd)); |
7d24ddcc | 1058 | |
8aab4757 VCG |
1059 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
1060 | memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); | |
7d24ddcc | 1061 | |
fdcc4bec JH |
1062 | /* Update remote key distribution in case the remote cleared |
1063 | * some bits that we had enabled in our request. | |
1064 | */ | |
1065 | smp->remote_key_dist &= rsp->resp_key_dist; | |
1066 | ||
c05b9339 | 1067 | auth |= req->auth_req; |
2b64d153 | 1068 | |
476585ec | 1069 | ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); |
2b64d153 BG |
1070 | if (ret) |
1071 | return SMP_UNSPECIFIED; | |
1072 | ||
4a74d658 | 1073 | set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
2b64d153 BG |
1074 | |
1075 | /* Can't compose response until we have been confirmed */ | |
4a74d658 | 1076 | if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) |
1cc61144 | 1077 | return smp_confirm(smp); |
da85e5e5 VCG |
1078 | |
1079 | return 0; | |
88ba43b6 AB |
1080 | } |
1081 | ||
da85e5e5 | 1082 | static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1083 | { |
5d88cc73 JH |
1084 | struct l2cap_chan *chan = conn->smp; |
1085 | struct smp_chan *smp = chan->data; | |
7d24ddcc | 1086 | |
88ba43b6 AB |
1087 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); |
1088 | ||
c46b98be | 1089 | if (skb->len < sizeof(smp->pcnf)) |
38e4a915 | 1090 | return SMP_INVALID_PARAMS; |
c46b98be | 1091 | |
1c1def09 VCG |
1092 | memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); |
1093 | skb_pull(skb, sizeof(smp->pcnf)); | |
88ba43b6 | 1094 | |
b28b4943 | 1095 | if (conn->hcon->out) { |
943a732a JH |
1096 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), |
1097 | smp->prnd); | |
b28b4943 JH |
1098 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); |
1099 | return 0; | |
1100 | } | |
1101 | ||
1102 | if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) | |
1cc61144 | 1103 | return smp_confirm(smp); |
943a732a | 1104 | else |
4a74d658 | 1105 | set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
da85e5e5 VCG |
1106 | |
1107 | return 0; | |
88ba43b6 AB |
1108 | } |
1109 | ||
da85e5e5 | 1110 | static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1111 | { |
5d88cc73 JH |
1112 | struct l2cap_chan *chan = conn->smp; |
1113 | struct smp_chan *smp = chan->data; | |
7d24ddcc | 1114 | |
8aab4757 | 1115 | BT_DBG("conn %p", conn); |
3158c50c | 1116 | |
c46b98be | 1117 | if (skb->len < sizeof(smp->rrnd)) |
38e4a915 | 1118 | return SMP_INVALID_PARAMS; |
c46b98be | 1119 | |
943a732a | 1120 | memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); |
8aab4757 | 1121 | skb_pull(skb, sizeof(smp->rrnd)); |
e7e62c85 | 1122 | |
861580a9 | 1123 | return smp_random(smp); |
88ba43b6 AB |
1124 | } |
1125 | ||
f81cd823 | 1126 | static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) |
988c5997 | 1127 | { |
c9839a11 | 1128 | struct smp_ltk *key; |
988c5997 VCG |
1129 | struct hci_conn *hcon = conn->hcon; |
1130 | ||
f3a73d97 | 1131 | key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); |
988c5997 | 1132 | if (!key) |
f81cd823 | 1133 | return false; |
988c5997 | 1134 | |
a6f7833c | 1135 | if (smp_ltk_sec_level(key) < sec_level) |
f81cd823 | 1136 | return false; |
4dab7864 | 1137 | |
51a8efd7 | 1138 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) |
f81cd823 | 1139 | return true; |
988c5997 | 1140 | |
c9839a11 VCG |
1141 | hci_le_start_enc(hcon, key->ediv, key->rand, key->val); |
1142 | hcon->enc_key_size = key->enc_size; | |
988c5997 | 1143 | |
fe59a05f JH |
1144 | /* We never store STKs for master role, so clear this flag */ |
1145 | clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); | |
1146 | ||
f81cd823 | 1147 | return true; |
988c5997 | 1148 | } |
f1560463 | 1149 | |
35dc6f83 JH |
1150 | bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, |
1151 | enum smp_key_pref key_pref) | |
854f4727 JH |
1152 | { |
1153 | if (sec_level == BT_SECURITY_LOW) | |
1154 | return true; | |
1155 | ||
35dc6f83 JH |
1156 | /* If we're encrypted with an STK but the caller prefers using |
1157 | * LTK claim insufficient security. This way we allow the | |
1158 | * connection to be re-encrypted with an LTK, even if the LTK | |
1159 | * provides the same level of security. Only exception is if we | |
1160 | * don't have an LTK (e.g. because of key distribution bits). | |
9ab65d60 | 1161 | */ |
35dc6f83 JH |
1162 | if (key_pref == SMP_USE_LTK && |
1163 | test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && | |
f3a73d97 | 1164 | hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) |
9ab65d60 JH |
1165 | return false; |
1166 | ||
854f4727 JH |
1167 | if (hcon->sec_level >= sec_level) |
1168 | return true; | |
1169 | ||
1170 | return false; | |
1171 | } | |
1172 | ||
da85e5e5 | 1173 | static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 AB |
1174 | { |
1175 | struct smp_cmd_security_req *rp = (void *) skb->data; | |
1176 | struct smp_cmd_pairing cp; | |
f1cb9af5 | 1177 | struct hci_conn *hcon = conn->hcon; |
0edb14de | 1178 | struct hci_dev *hdev = hcon->hdev; |
8aab4757 | 1179 | struct smp_chan *smp; |
c05b9339 | 1180 | u8 sec_level, auth; |
88ba43b6 AB |
1181 | |
1182 | BT_DBG("conn %p", conn); | |
1183 | ||
c46b98be | 1184 | if (skb->len < sizeof(*rp)) |
38e4a915 | 1185 | return SMP_INVALID_PARAMS; |
c46b98be | 1186 | |
40bef302 | 1187 | if (hcon->role != HCI_ROLE_MASTER) |
86ca9eac JH |
1188 | return SMP_CMD_NOTSUPP; |
1189 | ||
0edb14de | 1190 | auth = rp->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 1191 | |
5be5e275 | 1192 | if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) |
1afc2a1a JH |
1193 | sec_level = BT_SECURITY_MEDIUM; |
1194 | else | |
1195 | sec_level = authreq_to_seclevel(auth); | |
1196 | ||
35dc6f83 | 1197 | if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) |
854f4727 JH |
1198 | return 0; |
1199 | ||
c7262e71 JH |
1200 | if (sec_level > hcon->pending_sec_level) |
1201 | hcon->pending_sec_level = sec_level; | |
feb45eb5 | 1202 | |
4dab7864 | 1203 | if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) |
988c5997 VCG |
1204 | return 0; |
1205 | ||
8aab4757 | 1206 | smp = smp_chan_create(conn); |
c29d2444 JH |
1207 | if (!smp) |
1208 | return SMP_UNSPECIFIED; | |
d26a2345 | 1209 | |
b6ae8457 | 1210 | if (!test_bit(HCI_BONDABLE, &hcon->hdev->dev_flags) && |
c05b9339 | 1211 | (auth & SMP_AUTH_BONDING)) |
616d55be JH |
1212 | return SMP_PAIRING_NOTSUPP; |
1213 | ||
88ba43b6 | 1214 | skb_pull(skb, sizeof(*rp)); |
88ba43b6 | 1215 | |
da85e5e5 | 1216 | memset(&cp, 0, sizeof(cp)); |
c05b9339 | 1217 | build_pairing_cmd(conn, &cp, NULL, auth); |
88ba43b6 | 1218 | |
1c1def09 VCG |
1219 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
1220 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 1221 | |
88ba43b6 | 1222 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
b28b4943 | 1223 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); |
f1cb9af5 | 1224 | |
da85e5e5 | 1225 | return 0; |
88ba43b6 AB |
1226 | } |
1227 | ||
cc110922 | 1228 | int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) |
eb492e01 | 1229 | { |
cc110922 | 1230 | struct l2cap_conn *conn = hcon->l2cap_data; |
c68b7f12 | 1231 | struct l2cap_chan *chan; |
0a66cf20 | 1232 | struct smp_chan *smp; |
2b64d153 | 1233 | __u8 authreq; |
fc75cc86 | 1234 | int ret; |
eb492e01 | 1235 | |
3a0259bb VCG |
1236 | BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); |
1237 | ||
0a66cf20 JH |
1238 | /* This may be NULL if there's an unexpected disconnection */ |
1239 | if (!conn) | |
1240 | return 1; | |
1241 | ||
c68b7f12 JH |
1242 | chan = conn->smp; |
1243 | ||
757aee0f | 1244 | if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) |
2e65c9d2 AG |
1245 | return 1; |
1246 | ||
35dc6f83 | 1247 | if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) |
eb492e01 | 1248 | return 1; |
f1cb9af5 | 1249 | |
c7262e71 JH |
1250 | if (sec_level > hcon->pending_sec_level) |
1251 | hcon->pending_sec_level = sec_level; | |
1252 | ||
40bef302 | 1253 | if (hcon->role == HCI_ROLE_MASTER) |
c7262e71 JH |
1254 | if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) |
1255 | return 0; | |
d26a2345 | 1256 | |
fc75cc86 JH |
1257 | l2cap_chan_lock(chan); |
1258 | ||
1259 | /* If SMP is already in progress ignore this request */ | |
1260 | if (chan->data) { | |
1261 | ret = 0; | |
1262 | goto unlock; | |
1263 | } | |
d26a2345 | 1264 | |
8aab4757 | 1265 | smp = smp_chan_create(conn); |
fc75cc86 JH |
1266 | if (!smp) { |
1267 | ret = 1; | |
1268 | goto unlock; | |
1269 | } | |
2b64d153 BG |
1270 | |
1271 | authreq = seclevel_to_authreq(sec_level); | |
d26a2345 | 1272 | |
d2eb9e10 JH |
1273 | if (test_bit(HCI_SC_ENABLED, &hcon->hdev->dev_flags)) |
1274 | authreq |= SMP_AUTH_SC; | |
1275 | ||
79897d20 JH |
1276 | /* Require MITM if IO Capability allows or the security level |
1277 | * requires it. | |
2e233644 | 1278 | */ |
79897d20 | 1279 | if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || |
c7262e71 | 1280 | hcon->pending_sec_level > BT_SECURITY_MEDIUM) |
2e233644 JH |
1281 | authreq |= SMP_AUTH_MITM; |
1282 | ||
40bef302 | 1283 | if (hcon->role == HCI_ROLE_MASTER) { |
d26a2345 | 1284 | struct smp_cmd_pairing cp; |
f01ead31 | 1285 | |
2b64d153 | 1286 | build_pairing_cmd(conn, &cp, NULL, authreq); |
1c1def09 VCG |
1287 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
1288 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 1289 | |
eb492e01 | 1290 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
b28b4943 | 1291 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); |
eb492e01 AB |
1292 | } else { |
1293 | struct smp_cmd_security_req cp; | |
2b64d153 | 1294 | cp.auth_req = authreq; |
eb492e01 | 1295 | smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); |
b28b4943 | 1296 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); |
eb492e01 AB |
1297 | } |
1298 | ||
4a74d658 | 1299 | set_bit(SMP_FLAG_INITIATOR, &smp->flags); |
fc75cc86 | 1300 | ret = 0; |
edca792c | 1301 | |
fc75cc86 JH |
1302 | unlock: |
1303 | l2cap_chan_unlock(chan); | |
1304 | return ret; | |
eb492e01 AB |
1305 | } |
1306 | ||
7034b911 VCG |
1307 | static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1308 | { | |
16b90839 | 1309 | struct smp_cmd_encrypt_info *rp = (void *) skb->data; |
5d88cc73 JH |
1310 | struct l2cap_chan *chan = conn->smp; |
1311 | struct smp_chan *smp = chan->data; | |
16b90839 | 1312 | |
c46b98be JH |
1313 | BT_DBG("conn %p", conn); |
1314 | ||
1315 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1316 | return SMP_INVALID_PARAMS; |
c46b98be | 1317 | |
b28b4943 | 1318 | SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); |
6131ddc8 | 1319 | |
16b90839 VCG |
1320 | skb_pull(skb, sizeof(*rp)); |
1321 | ||
1c1def09 | 1322 | memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); |
16b90839 | 1323 | |
7034b911 VCG |
1324 | return 0; |
1325 | } | |
1326 | ||
1327 | static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) | |
1328 | { | |
16b90839 | 1329 | struct smp_cmd_master_ident *rp = (void *) skb->data; |
5d88cc73 JH |
1330 | struct l2cap_chan *chan = conn->smp; |
1331 | struct smp_chan *smp = chan->data; | |
c9839a11 VCG |
1332 | struct hci_dev *hdev = conn->hcon->hdev; |
1333 | struct hci_conn *hcon = conn->hcon; | |
23d0e128 | 1334 | struct smp_ltk *ltk; |
c9839a11 | 1335 | u8 authenticated; |
16b90839 | 1336 | |
c46b98be JH |
1337 | BT_DBG("conn %p", conn); |
1338 | ||
1339 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1340 | return SMP_INVALID_PARAMS; |
c46b98be | 1341 | |
9747a9f3 JH |
1342 | /* Mark the information as received */ |
1343 | smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; | |
1344 | ||
b28b4943 JH |
1345 | if (smp->remote_key_dist & SMP_DIST_ID_KEY) |
1346 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); | |
196332f5 JH |
1347 | else if (smp->remote_key_dist & SMP_DIST_SIGN) |
1348 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
b28b4943 | 1349 | |
16b90839 | 1350 | skb_pull(skb, sizeof(*rp)); |
7034b911 | 1351 | |
ce39fb4e | 1352 | authenticated = (hcon->sec_level == BT_SECURITY_HIGH); |
2ceba539 | 1353 | ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, |
23d0e128 JH |
1354 | authenticated, smp->tk, smp->enc_key_size, |
1355 | rp->ediv, rp->rand); | |
1356 | smp->ltk = ltk; | |
c6e81e9a | 1357 | if (!(smp->remote_key_dist & KEY_DIST_MASK)) |
d6268e86 | 1358 | smp_distribute_keys(smp); |
7034b911 VCG |
1359 | |
1360 | return 0; | |
1361 | } | |
1362 | ||
fd349c02 JH |
1363 | static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1364 | { | |
1365 | struct smp_cmd_ident_info *info = (void *) skb->data; | |
5d88cc73 JH |
1366 | struct l2cap_chan *chan = conn->smp; |
1367 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
1368 | |
1369 | BT_DBG(""); | |
1370 | ||
1371 | if (skb->len < sizeof(*info)) | |
38e4a915 | 1372 | return SMP_INVALID_PARAMS; |
fd349c02 | 1373 | |
b28b4943 | 1374 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); |
6131ddc8 | 1375 | |
fd349c02 JH |
1376 | skb_pull(skb, sizeof(*info)); |
1377 | ||
1378 | memcpy(smp->irk, info->irk, 16); | |
1379 | ||
1380 | return 0; | |
1381 | } | |
1382 | ||
1383 | static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, | |
1384 | struct sk_buff *skb) | |
1385 | { | |
1386 | struct smp_cmd_ident_addr_info *info = (void *) skb->data; | |
5d88cc73 JH |
1387 | struct l2cap_chan *chan = conn->smp; |
1388 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
1389 | struct hci_conn *hcon = conn->hcon; |
1390 | bdaddr_t rpa; | |
1391 | ||
1392 | BT_DBG(""); | |
1393 | ||
1394 | if (skb->len < sizeof(*info)) | |
38e4a915 | 1395 | return SMP_INVALID_PARAMS; |
fd349c02 | 1396 | |
9747a9f3 JH |
1397 | /* Mark the information as received */ |
1398 | smp->remote_key_dist &= ~SMP_DIST_ID_KEY; | |
1399 | ||
b28b4943 JH |
1400 | if (smp->remote_key_dist & SMP_DIST_SIGN) |
1401 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
1402 | ||
fd349c02 JH |
1403 | skb_pull(skb, sizeof(*info)); |
1404 | ||
a9a58f86 JH |
1405 | /* Strictly speaking the Core Specification (4.1) allows sending |
1406 | * an empty address which would force us to rely on just the IRK | |
1407 | * as "identity information". However, since such | |
1408 | * implementations are not known of and in order to not over | |
1409 | * complicate our implementation, simply pretend that we never | |
1410 | * received an IRK for such a device. | |
1411 | */ | |
1412 | if (!bacmp(&info->bdaddr, BDADDR_ANY)) { | |
1413 | BT_ERR("Ignoring IRK with no identity address"); | |
31dd624e | 1414 | goto distribute; |
a9a58f86 JH |
1415 | } |
1416 | ||
fd349c02 JH |
1417 | bacpy(&smp->id_addr, &info->bdaddr); |
1418 | smp->id_addr_type = info->addr_type; | |
1419 | ||
1420 | if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) | |
1421 | bacpy(&rpa, &hcon->dst); | |
1422 | else | |
1423 | bacpy(&rpa, BDADDR_ANY); | |
1424 | ||
23d0e128 JH |
1425 | smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, |
1426 | smp->id_addr_type, smp->irk, &rpa); | |
fd349c02 | 1427 | |
31dd624e | 1428 | distribute: |
c6e81e9a JH |
1429 | if (!(smp->remote_key_dist & KEY_DIST_MASK)) |
1430 | smp_distribute_keys(smp); | |
fd349c02 JH |
1431 | |
1432 | return 0; | |
1433 | } | |
1434 | ||
7ee4ea36 MH |
1435 | static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1436 | { | |
1437 | struct smp_cmd_sign_info *rp = (void *) skb->data; | |
5d88cc73 JH |
1438 | struct l2cap_chan *chan = conn->smp; |
1439 | struct smp_chan *smp = chan->data; | |
7ee4ea36 MH |
1440 | struct smp_csrk *csrk; |
1441 | ||
1442 | BT_DBG("conn %p", conn); | |
1443 | ||
1444 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1445 | return SMP_INVALID_PARAMS; |
7ee4ea36 | 1446 | |
7ee4ea36 MH |
1447 | /* Mark the information as received */ |
1448 | smp->remote_key_dist &= ~SMP_DIST_SIGN; | |
1449 | ||
1450 | skb_pull(skb, sizeof(*rp)); | |
1451 | ||
7ee4ea36 MH |
1452 | csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); |
1453 | if (csrk) { | |
1454 | csrk->master = 0x01; | |
1455 | memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); | |
1456 | } | |
1457 | smp->csrk = csrk; | |
d6268e86 | 1458 | smp_distribute_keys(smp); |
7ee4ea36 MH |
1459 | |
1460 | return 0; | |
1461 | } | |
1462 | ||
4befb867 | 1463 | static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) |
eb492e01 | 1464 | { |
5d88cc73 | 1465 | struct l2cap_conn *conn = chan->conn; |
7b9899db | 1466 | struct hci_conn *hcon = conn->hcon; |
b28b4943 | 1467 | struct smp_chan *smp; |
92381f5c | 1468 | __u8 code, reason; |
eb492e01 AB |
1469 | int err = 0; |
1470 | ||
7b9899db MH |
1471 | if (hcon->type != LE_LINK) { |
1472 | kfree_skb(skb); | |
3432711f | 1473 | return 0; |
7b9899db MH |
1474 | } |
1475 | ||
8ae9b984 | 1476 | if (skb->len < 1) |
92381f5c | 1477 | return -EILSEQ; |
92381f5c | 1478 | |
06ae3314 | 1479 | if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) { |
2e65c9d2 AG |
1480 | reason = SMP_PAIRING_NOTSUPP; |
1481 | goto done; | |
1482 | } | |
1483 | ||
92381f5c | 1484 | code = skb->data[0]; |
eb492e01 AB |
1485 | skb_pull(skb, sizeof(code)); |
1486 | ||
b28b4943 JH |
1487 | smp = chan->data; |
1488 | ||
1489 | if (code > SMP_CMD_MAX) | |
1490 | goto drop; | |
1491 | ||
24bd0bd9 | 1492 | if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) |
b28b4943 JH |
1493 | goto drop; |
1494 | ||
1495 | /* If we don't have a context the only allowed commands are | |
1496 | * pairing request and security request. | |
8cf9fa12 | 1497 | */ |
b28b4943 JH |
1498 | if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) |
1499 | goto drop; | |
8cf9fa12 | 1500 | |
eb492e01 AB |
1501 | switch (code) { |
1502 | case SMP_CMD_PAIRING_REQ: | |
da85e5e5 | 1503 | reason = smp_cmd_pairing_req(conn, skb); |
eb492e01 AB |
1504 | break; |
1505 | ||
1506 | case SMP_CMD_PAIRING_FAIL: | |
84794e11 | 1507 | smp_failure(conn, 0); |
da85e5e5 | 1508 | err = -EPERM; |
eb492e01 AB |
1509 | break; |
1510 | ||
1511 | case SMP_CMD_PAIRING_RSP: | |
da85e5e5 | 1512 | reason = smp_cmd_pairing_rsp(conn, skb); |
88ba43b6 AB |
1513 | break; |
1514 | ||
1515 | case SMP_CMD_SECURITY_REQ: | |
da85e5e5 | 1516 | reason = smp_cmd_security_req(conn, skb); |
88ba43b6 AB |
1517 | break; |
1518 | ||
eb492e01 | 1519 | case SMP_CMD_PAIRING_CONFIRM: |
da85e5e5 | 1520 | reason = smp_cmd_pairing_confirm(conn, skb); |
88ba43b6 AB |
1521 | break; |
1522 | ||
eb492e01 | 1523 | case SMP_CMD_PAIRING_RANDOM: |
da85e5e5 | 1524 | reason = smp_cmd_pairing_random(conn, skb); |
88ba43b6 AB |
1525 | break; |
1526 | ||
eb492e01 | 1527 | case SMP_CMD_ENCRYPT_INFO: |
7034b911 VCG |
1528 | reason = smp_cmd_encrypt_info(conn, skb); |
1529 | break; | |
1530 | ||
eb492e01 | 1531 | case SMP_CMD_MASTER_IDENT: |
7034b911 VCG |
1532 | reason = smp_cmd_master_ident(conn, skb); |
1533 | break; | |
1534 | ||
eb492e01 | 1535 | case SMP_CMD_IDENT_INFO: |
fd349c02 JH |
1536 | reason = smp_cmd_ident_info(conn, skb); |
1537 | break; | |
1538 | ||
eb492e01 | 1539 | case SMP_CMD_IDENT_ADDR_INFO: |
fd349c02 JH |
1540 | reason = smp_cmd_ident_addr_info(conn, skb); |
1541 | break; | |
1542 | ||
eb492e01 | 1543 | case SMP_CMD_SIGN_INFO: |
7ee4ea36 | 1544 | reason = smp_cmd_sign_info(conn, skb); |
7034b911 VCG |
1545 | break; |
1546 | ||
eb492e01 AB |
1547 | default: |
1548 | BT_DBG("Unknown command code 0x%2.2x", code); | |
eb492e01 | 1549 | reason = SMP_CMD_NOTSUPP; |
3a0259bb | 1550 | goto done; |
eb492e01 AB |
1551 | } |
1552 | ||
3a0259bb | 1553 | done: |
9b7b18ef JH |
1554 | if (!err) { |
1555 | if (reason) | |
1556 | smp_failure(conn, reason); | |
8ae9b984 | 1557 | kfree_skb(skb); |
9b7b18ef JH |
1558 | } |
1559 | ||
eb492e01 | 1560 | return err; |
b28b4943 JH |
1561 | |
1562 | drop: | |
1563 | BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name, | |
1564 | code, &hcon->dst); | |
1565 | kfree_skb(skb); | |
1566 | return 0; | |
eb492e01 | 1567 | } |
7034b911 | 1568 | |
70db83c4 JH |
1569 | static void smp_teardown_cb(struct l2cap_chan *chan, int err) |
1570 | { | |
1571 | struct l2cap_conn *conn = chan->conn; | |
1572 | ||
1573 | BT_DBG("chan %p", chan); | |
1574 | ||
fc75cc86 | 1575 | if (chan->data) |
5d88cc73 | 1576 | smp_chan_destroy(conn); |
5d88cc73 | 1577 | |
70db83c4 JH |
1578 | conn->smp = NULL; |
1579 | l2cap_chan_put(chan); | |
1580 | } | |
1581 | ||
44f1a7ab JH |
1582 | static void smp_resume_cb(struct l2cap_chan *chan) |
1583 | { | |
b68fda68 | 1584 | struct smp_chan *smp = chan->data; |
44f1a7ab JH |
1585 | struct l2cap_conn *conn = chan->conn; |
1586 | struct hci_conn *hcon = conn->hcon; | |
1587 | ||
1588 | BT_DBG("chan %p", chan); | |
1589 | ||
86d1407c JH |
1590 | if (!smp) |
1591 | return; | |
b68fda68 | 1592 | |
84bc0db5 JH |
1593 | if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) |
1594 | return; | |
1595 | ||
86d1407c JH |
1596 | cancel_delayed_work(&smp->security_timer); |
1597 | ||
d6268e86 | 1598 | smp_distribute_keys(smp); |
44f1a7ab JH |
1599 | } |
1600 | ||
70db83c4 JH |
1601 | static void smp_ready_cb(struct l2cap_chan *chan) |
1602 | { | |
1603 | struct l2cap_conn *conn = chan->conn; | |
1604 | ||
1605 | BT_DBG("chan %p", chan); | |
1606 | ||
1607 | conn->smp = chan; | |
1608 | l2cap_chan_hold(chan); | |
1609 | } | |
1610 | ||
4befb867 JH |
1611 | static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) |
1612 | { | |
1613 | int err; | |
1614 | ||
1615 | BT_DBG("chan %p", chan); | |
1616 | ||
1617 | err = smp_sig_channel(chan, skb); | |
1618 | if (err) { | |
b68fda68 | 1619 | struct smp_chan *smp = chan->data; |
4befb867 | 1620 | |
b68fda68 JH |
1621 | if (smp) |
1622 | cancel_delayed_work_sync(&smp->security_timer); | |
4befb867 | 1623 | |
1e91c29e | 1624 | hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); |
4befb867 JH |
1625 | } |
1626 | ||
1627 | return err; | |
1628 | } | |
1629 | ||
70db83c4 JH |
1630 | static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, |
1631 | unsigned long hdr_len, | |
1632 | unsigned long len, int nb) | |
1633 | { | |
1634 | struct sk_buff *skb; | |
1635 | ||
1636 | skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); | |
1637 | if (!skb) | |
1638 | return ERR_PTR(-ENOMEM); | |
1639 | ||
1640 | skb->priority = HCI_PRIO_MAX; | |
1641 | bt_cb(skb)->chan = chan; | |
1642 | ||
1643 | return skb; | |
1644 | } | |
1645 | ||
1646 | static const struct l2cap_ops smp_chan_ops = { | |
1647 | .name = "Security Manager", | |
1648 | .ready = smp_ready_cb, | |
5d88cc73 | 1649 | .recv = smp_recv_cb, |
70db83c4 JH |
1650 | .alloc_skb = smp_alloc_skb_cb, |
1651 | .teardown = smp_teardown_cb, | |
44f1a7ab | 1652 | .resume = smp_resume_cb, |
70db83c4 JH |
1653 | |
1654 | .new_connection = l2cap_chan_no_new_connection, | |
70db83c4 JH |
1655 | .state_change = l2cap_chan_no_state_change, |
1656 | .close = l2cap_chan_no_close, | |
1657 | .defer = l2cap_chan_no_defer, | |
1658 | .suspend = l2cap_chan_no_suspend, | |
70db83c4 JH |
1659 | .set_shutdown = l2cap_chan_no_set_shutdown, |
1660 | .get_sndtimeo = l2cap_chan_no_get_sndtimeo, | |
1661 | .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec, | |
1662 | }; | |
1663 | ||
1664 | static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) | |
1665 | { | |
1666 | struct l2cap_chan *chan; | |
1667 | ||
1668 | BT_DBG("pchan %p", pchan); | |
1669 | ||
1670 | chan = l2cap_chan_create(); | |
1671 | if (!chan) | |
1672 | return NULL; | |
1673 | ||
1674 | chan->chan_type = pchan->chan_type; | |
1675 | chan->ops = &smp_chan_ops; | |
1676 | chan->scid = pchan->scid; | |
1677 | chan->dcid = chan->scid; | |
1678 | chan->imtu = pchan->imtu; | |
1679 | chan->omtu = pchan->omtu; | |
1680 | chan->mode = pchan->mode; | |
1681 | ||
abe84903 JH |
1682 | /* Other L2CAP channels may request SMP routines in order to |
1683 | * change the security level. This means that the SMP channel | |
1684 | * lock must be considered in its own category to avoid lockdep | |
1685 | * warnings. | |
1686 | */ | |
1687 | atomic_set(&chan->nesting, L2CAP_NESTING_SMP); | |
1688 | ||
70db83c4 JH |
1689 | BT_DBG("created chan %p", chan); |
1690 | ||
1691 | return chan; | |
1692 | } | |
1693 | ||
1694 | static const struct l2cap_ops smp_root_chan_ops = { | |
1695 | .name = "Security Manager Root", | |
1696 | .new_connection = smp_new_conn_cb, | |
1697 | ||
1698 | /* None of these are implemented for the root channel */ | |
1699 | .close = l2cap_chan_no_close, | |
1700 | .alloc_skb = l2cap_chan_no_alloc_skb, | |
1701 | .recv = l2cap_chan_no_recv, | |
1702 | .state_change = l2cap_chan_no_state_change, | |
1703 | .teardown = l2cap_chan_no_teardown, | |
1704 | .ready = l2cap_chan_no_ready, | |
1705 | .defer = l2cap_chan_no_defer, | |
1706 | .suspend = l2cap_chan_no_suspend, | |
1707 | .resume = l2cap_chan_no_resume, | |
1708 | .set_shutdown = l2cap_chan_no_set_shutdown, | |
1709 | .get_sndtimeo = l2cap_chan_no_get_sndtimeo, | |
1710 | .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec, | |
1711 | }; | |
1712 | ||
711eafe3 JH |
1713 | int smp_register(struct hci_dev *hdev) |
1714 | { | |
70db83c4 | 1715 | struct l2cap_chan *chan; |
defce9e8 | 1716 | struct crypto_blkcipher *tfm_aes; |
70db83c4 | 1717 | |
711eafe3 JH |
1718 | BT_DBG("%s", hdev->name); |
1719 | ||
adae20cb | 1720 | tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0); |
defce9e8 JH |
1721 | if (IS_ERR(tfm_aes)) { |
1722 | int err = PTR_ERR(tfm_aes); | |
711eafe3 | 1723 | BT_ERR("Unable to create crypto context"); |
711eafe3 JH |
1724 | return err; |
1725 | } | |
1726 | ||
70db83c4 JH |
1727 | chan = l2cap_chan_create(); |
1728 | if (!chan) { | |
defce9e8 | 1729 | crypto_free_blkcipher(tfm_aes); |
70db83c4 JH |
1730 | return -ENOMEM; |
1731 | } | |
1732 | ||
defce9e8 JH |
1733 | chan->data = tfm_aes; |
1734 | ||
5d88cc73 | 1735 | l2cap_add_scid(chan, L2CAP_CID_SMP); |
70db83c4 JH |
1736 | |
1737 | l2cap_chan_set_defaults(chan); | |
1738 | ||
1739 | bacpy(&chan->src, &hdev->bdaddr); | |
1740 | chan->src_type = BDADDR_LE_PUBLIC; | |
1741 | chan->state = BT_LISTEN; | |
1742 | chan->mode = L2CAP_MODE_BASIC; | |
1743 | chan->imtu = L2CAP_DEFAULT_MTU; | |
1744 | chan->ops = &smp_root_chan_ops; | |
1745 | ||
abe84903 JH |
1746 | /* Set correct nesting level for a parent/listening channel */ |
1747 | atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); | |
1748 | ||
70db83c4 JH |
1749 | hdev->smp_data = chan; |
1750 | ||
711eafe3 JH |
1751 | return 0; |
1752 | } | |
1753 | ||
1754 | void smp_unregister(struct hci_dev *hdev) | |
1755 | { | |
70db83c4 | 1756 | struct l2cap_chan *chan = hdev->smp_data; |
defce9e8 | 1757 | struct crypto_blkcipher *tfm_aes; |
70db83c4 JH |
1758 | |
1759 | if (!chan) | |
1760 | return; | |
1761 | ||
1762 | BT_DBG("%s chan %p", hdev->name, chan); | |
711eafe3 | 1763 | |
defce9e8 JH |
1764 | tfm_aes = chan->data; |
1765 | if (tfm_aes) { | |
1766 | chan->data = NULL; | |
1767 | crypto_free_blkcipher(tfm_aes); | |
711eafe3 | 1768 | } |
70db83c4 JH |
1769 | |
1770 | hdev->smp_data = NULL; | |
1771 | l2cap_chan_put(chan); | |
711eafe3 | 1772 | } |