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 | 31 | |
3b19146d | 32 | #include "ecc.h" |
ac4b7236 | 33 | #include "smp.h" |
d22ef0bc | 34 | |
b28b4943 | 35 | #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) |
b28b4943 | 36 | |
3b19146d JH |
37 | /* Keys which are not distributed with Secure Connections */ |
38 | #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY); | |
39 | ||
17b02e62 | 40 | #define SMP_TIMEOUT msecs_to_jiffies(30000) |
5d3de7df | 41 | |
0edb14de JH |
42 | #define AUTH_REQ_MASK(dev) (test_bit(HCI_SC_ENABLED, &(dev)->dev_flags) ? \ |
43 | 0x1f : 0x07) | |
44 | #define KEY_DIST_MASK 0x07 | |
065a13e2 | 45 | |
cbbbe3e2 JH |
46 | /* Maximum message length that can be passed to aes_cmac */ |
47 | #define CMAC_MSG_MAX 80 | |
48 | ||
533e35d4 JH |
49 | enum { |
50 | SMP_FLAG_TK_VALID, | |
51 | SMP_FLAG_CFM_PENDING, | |
52 | SMP_FLAG_MITM_AUTH, | |
53 | SMP_FLAG_COMPLETE, | |
54 | SMP_FLAG_INITIATOR, | |
65668776 | 55 | SMP_FLAG_SC, |
d8f8edbe | 56 | SMP_FLAG_REMOTE_PK, |
533e35d4 | 57 | }; |
4bc58f51 JH |
58 | |
59 | struct smp_chan { | |
b68fda68 JH |
60 | struct l2cap_conn *conn; |
61 | struct delayed_work security_timer; | |
b28b4943 | 62 | unsigned long allow_cmd; /* Bitmask of allowed commands */ |
b68fda68 | 63 | |
4bc58f51 JH |
64 | u8 preq[7]; /* SMP Pairing Request */ |
65 | u8 prsp[7]; /* SMP Pairing Response */ | |
66 | u8 prnd[16]; /* SMP Pairing Random (local) */ | |
67 | u8 rrnd[16]; /* SMP Pairing Random (remote) */ | |
68 | u8 pcnf[16]; /* SMP Pairing Confirm */ | |
69 | u8 tk[16]; /* SMP Temporary Key */ | |
70 | u8 enc_key_size; | |
71 | u8 remote_key_dist; | |
72 | bdaddr_t id_addr; | |
73 | u8 id_addr_type; | |
74 | u8 irk[16]; | |
75 | struct smp_csrk *csrk; | |
76 | struct smp_csrk *slave_csrk; | |
77 | struct smp_ltk *ltk; | |
78 | struct smp_ltk *slave_ltk; | |
79 | struct smp_irk *remote_irk; | |
4a74d658 | 80 | unsigned long flags; |
6a7bd103 | 81 | |
3b19146d JH |
82 | /* Secure Connections variables */ |
83 | u8 local_pk[64]; | |
84 | u8 local_sk[32]; | |
d8f8edbe JH |
85 | u8 remote_pk[64]; |
86 | u8 dhkey[32]; | |
760b018b | 87 | u8 mackey[16]; |
3b19146d | 88 | |
6a7bd103 | 89 | struct crypto_blkcipher *tfm_aes; |
407cecf6 | 90 | struct crypto_hash *tfm_cmac; |
4bc58f51 JH |
91 | }; |
92 | ||
8a2936f4 | 93 | static inline void swap_buf(const u8 *src, u8 *dst, size_t len) |
d22ef0bc | 94 | { |
8a2936f4 | 95 | size_t i; |
d22ef0bc | 96 | |
8a2936f4 JH |
97 | for (i = 0; i < len; i++) |
98 | dst[len - 1 - i] = src[i]; | |
d22ef0bc AB |
99 | } |
100 | ||
cbbbe3e2 JH |
101 | static int aes_cmac(struct crypto_hash *tfm, const u8 k[16], const u8 *m, |
102 | size_t len, u8 mac[16]) | |
103 | { | |
104 | uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; | |
105 | struct hash_desc desc; | |
106 | struct scatterlist sg; | |
107 | int err; | |
108 | ||
109 | if (len > CMAC_MSG_MAX) | |
110 | return -EFBIG; | |
111 | ||
112 | if (!tfm) { | |
113 | BT_ERR("tfm %p", tfm); | |
114 | return -EINVAL; | |
115 | } | |
116 | ||
117 | desc.tfm = tfm; | |
118 | desc.flags = 0; | |
119 | ||
120 | crypto_hash_init(&desc); | |
121 | ||
122 | /* Swap key and message from LSB to MSB */ | |
123 | swap_buf(k, tmp, 16); | |
124 | swap_buf(m, msg_msb, len); | |
125 | ||
126 | BT_DBG("msg (len %zu) %*phN", len, (int) len, m); | |
127 | BT_DBG("key %16phN", k); | |
128 | ||
129 | err = crypto_hash_setkey(tfm, tmp, 16); | |
130 | if (err) { | |
131 | BT_ERR("cipher setkey failed: %d", err); | |
132 | return err; | |
133 | } | |
134 | ||
135 | sg_init_one(&sg, msg_msb, len); | |
136 | ||
137 | err = crypto_hash_update(&desc, &sg, len); | |
138 | if (err) { | |
139 | BT_ERR("Hash update error %d", err); | |
140 | return err; | |
141 | } | |
142 | ||
143 | err = crypto_hash_final(&desc, mac_msb); | |
144 | if (err) { | |
145 | BT_ERR("Hash final error %d", err); | |
146 | return err; | |
147 | } | |
148 | ||
149 | swap_buf(mac_msb, mac, 16); | |
150 | ||
151 | BT_DBG("mac %16phN", mac); | |
152 | ||
153 | return 0; | |
154 | } | |
155 | ||
156 | static int smp_f4(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32], | |
157 | const u8 x[16], u8 z, u8 res[16]) | |
158 | { | |
159 | u8 m[65]; | |
160 | int err; | |
161 | ||
162 | BT_DBG("u %32phN", u); | |
163 | BT_DBG("v %32phN", v); | |
164 | BT_DBG("x %16phN z %02x", x, z); | |
165 | ||
166 | m[0] = z; | |
167 | memcpy(m + 1, v, 32); | |
168 | memcpy(m + 33, u, 32); | |
169 | ||
170 | err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); | |
171 | if (err) | |
172 | return err; | |
173 | ||
174 | BT_DBG("res %16phN", res); | |
175 | ||
176 | return err; | |
177 | } | |
178 | ||
760b018b JH |
179 | static int smp_f5(struct crypto_hash *tfm_cmac, u8 w[32], u8 n1[16], u8 n2[16], |
180 | u8 a1[7], u8 a2[7], u8 mackey[16], u8 ltk[16]) | |
181 | { | |
182 | /* The btle, salt and length "magic" values are as defined in | |
183 | * the SMP section of the Bluetooth core specification. In ASCII | |
184 | * the btle value ends up being 'btle'. The salt is just a | |
185 | * random number whereas length is the value 256 in little | |
186 | * endian format. | |
187 | */ | |
188 | const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; | |
189 | const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, | |
190 | 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; | |
191 | const u8 length[2] = { 0x00, 0x01 }; | |
192 | u8 m[53], t[16]; | |
193 | int err; | |
194 | ||
195 | BT_DBG("w %32phN", w); | |
196 | BT_DBG("n1 %16phN n2 %16phN", n1, n2); | |
197 | BT_DBG("a1 %7phN a2 %7phN", a1, a2); | |
198 | ||
199 | err = aes_cmac(tfm_cmac, salt, w, 32, t); | |
200 | if (err) | |
201 | return err; | |
202 | ||
203 | BT_DBG("t %16phN", t); | |
204 | ||
205 | memcpy(m, length, 2); | |
206 | memcpy(m + 2, a2, 7); | |
207 | memcpy(m + 9, a1, 7); | |
208 | memcpy(m + 16, n2, 16); | |
209 | memcpy(m + 32, n1, 16); | |
210 | memcpy(m + 48, btle, 4); | |
211 | ||
212 | m[52] = 0; /* Counter */ | |
213 | ||
214 | err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); | |
215 | if (err) | |
216 | return err; | |
217 | ||
218 | BT_DBG("mackey %16phN", mackey); | |
219 | ||
220 | m[52] = 1; /* Counter */ | |
221 | ||
222 | err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); | |
223 | if (err) | |
224 | return err; | |
225 | ||
226 | BT_DBG("ltk %16phN", ltk); | |
227 | ||
228 | return 0; | |
229 | } | |
230 | ||
231 | static int smp_f6(struct crypto_hash *tfm_cmac, const u8 w[16], | |
232 | const u8 n1[16], u8 n2[16], const u8 r[16], | |
233 | const u8 io_cap[3], const u8 a1[7], const u8 a2[7], | |
234 | u8 res[16]) | |
235 | { | |
236 | u8 m[65]; | |
237 | int err; | |
238 | ||
239 | BT_DBG("w %16phN", w); | |
240 | BT_DBG("n1 %16phN n2 %16phN", n1, n2); | |
241 | BT_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); | |
242 | ||
243 | memcpy(m, a2, 7); | |
244 | memcpy(m + 7, a1, 7); | |
245 | memcpy(m + 14, io_cap, 3); | |
246 | memcpy(m + 17, r, 16); | |
247 | memcpy(m + 33, n2, 16); | |
248 | memcpy(m + 49, n1, 16); | |
249 | ||
250 | err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); | |
251 | if (err) | |
252 | return err; | |
253 | ||
254 | BT_DBG("res %16phN", res); | |
255 | ||
256 | return err; | |
257 | } | |
258 | ||
191dc7fe JH |
259 | static int smp_g2(struct crypto_hash *tfm_cmac, const u8 u[32], const u8 v[32], |
260 | const u8 x[16], const u8 y[16], u32 *val) | |
261 | { | |
262 | u8 m[80], tmp[16]; | |
263 | int err; | |
264 | ||
265 | BT_DBG("u %32phN", u); | |
266 | BT_DBG("v %32phN", v); | |
267 | BT_DBG("x %16phN y %16phN", x, y); | |
268 | ||
269 | memcpy(m, y, 16); | |
270 | memcpy(m + 16, v, 32); | |
271 | memcpy(m + 48, u, 32); | |
272 | ||
273 | err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); | |
274 | if (err) | |
275 | return err; | |
276 | ||
277 | *val = get_unaligned_le32(tmp); | |
278 | *val %= 1000000; | |
279 | ||
280 | BT_DBG("val %06u", *val); | |
281 | ||
282 | return 0; | |
283 | } | |
284 | ||
d22ef0bc AB |
285 | static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) |
286 | { | |
287 | struct blkcipher_desc desc; | |
288 | struct scatterlist sg; | |
943a732a | 289 | uint8_t tmp[16], data[16]; |
201a5929 | 290 | int err; |
d22ef0bc AB |
291 | |
292 | if (tfm == NULL) { | |
293 | BT_ERR("tfm %p", tfm); | |
294 | return -EINVAL; | |
295 | } | |
296 | ||
297 | desc.tfm = tfm; | |
298 | desc.flags = 0; | |
299 | ||
943a732a | 300 | /* The most significant octet of key corresponds to k[0] */ |
8a2936f4 | 301 | swap_buf(k, tmp, 16); |
943a732a JH |
302 | |
303 | err = crypto_blkcipher_setkey(tfm, tmp, 16); | |
d22ef0bc AB |
304 | if (err) { |
305 | BT_ERR("cipher setkey failed: %d", err); | |
306 | return err; | |
307 | } | |
308 | ||
943a732a | 309 | /* Most significant octet of plaintextData corresponds to data[0] */ |
8a2936f4 | 310 | swap_buf(r, data, 16); |
943a732a JH |
311 | |
312 | sg_init_one(&sg, data, 16); | |
d22ef0bc | 313 | |
d22ef0bc AB |
314 | err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16); |
315 | if (err) | |
316 | BT_ERR("Encrypt data error %d", err); | |
317 | ||
943a732a | 318 | /* Most significant octet of encryptedData corresponds to data[0] */ |
8a2936f4 | 319 | swap_buf(data, r, 16); |
943a732a | 320 | |
d22ef0bc AB |
321 | return err; |
322 | } | |
323 | ||
60478054 JH |
324 | static int smp_ah(struct crypto_blkcipher *tfm, u8 irk[16], u8 r[3], u8 res[3]) |
325 | { | |
943a732a | 326 | u8 _res[16]; |
60478054 JH |
327 | int err; |
328 | ||
329 | /* r' = padding || r */ | |
943a732a JH |
330 | memcpy(_res, r, 3); |
331 | memset(_res + 3, 0, 13); | |
60478054 | 332 | |
943a732a | 333 | err = smp_e(tfm, irk, _res); |
60478054 JH |
334 | if (err) { |
335 | BT_ERR("Encrypt error"); | |
336 | return err; | |
337 | } | |
338 | ||
339 | /* The output of the random address function ah is: | |
340 | * ah(h, r) = e(k, r') mod 2^24 | |
341 | * The output of the security function e is then truncated to 24 bits | |
342 | * by taking the least significant 24 bits of the output of e as the | |
343 | * result of ah. | |
344 | */ | |
943a732a | 345 | memcpy(res, _res, 3); |
60478054 JH |
346 | |
347 | return 0; | |
348 | } | |
349 | ||
defce9e8 | 350 | bool smp_irk_matches(struct hci_dev *hdev, u8 irk[16], bdaddr_t *bdaddr) |
60478054 | 351 | { |
defce9e8 JH |
352 | struct l2cap_chan *chan = hdev->smp_data; |
353 | struct crypto_blkcipher *tfm; | |
60478054 JH |
354 | u8 hash[3]; |
355 | int err; | |
356 | ||
defce9e8 JH |
357 | if (!chan || !chan->data) |
358 | return false; | |
359 | ||
360 | tfm = chan->data; | |
361 | ||
60478054 JH |
362 | BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk); |
363 | ||
364 | err = smp_ah(tfm, irk, &bdaddr->b[3], hash); | |
365 | if (err) | |
366 | return false; | |
367 | ||
368 | return !memcmp(bdaddr->b, hash, 3); | |
369 | } | |
370 | ||
defce9e8 | 371 | int smp_generate_rpa(struct hci_dev *hdev, u8 irk[16], bdaddr_t *rpa) |
b1e2b3ae | 372 | { |
defce9e8 JH |
373 | struct l2cap_chan *chan = hdev->smp_data; |
374 | struct crypto_blkcipher *tfm; | |
b1e2b3ae JH |
375 | int err; |
376 | ||
defce9e8 JH |
377 | if (!chan || !chan->data) |
378 | return -EOPNOTSUPP; | |
379 | ||
380 | tfm = chan->data; | |
381 | ||
b1e2b3ae JH |
382 | get_random_bytes(&rpa->b[3], 3); |
383 | ||
384 | rpa->b[5] &= 0x3f; /* Clear two most significant bits */ | |
385 | rpa->b[5] |= 0x40; /* Set second most significant bit */ | |
386 | ||
387 | err = smp_ah(tfm, irk, &rpa->b[3], rpa->b); | |
388 | if (err < 0) | |
389 | return err; | |
390 | ||
391 | BT_DBG("RPA %pMR", rpa); | |
392 | ||
393 | return 0; | |
394 | } | |
395 | ||
e491eaf3 JH |
396 | static int smp_c1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r[16], |
397 | u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia, u8 _rat, | |
398 | bdaddr_t *ra, u8 res[16]) | |
d22ef0bc AB |
399 | { |
400 | u8 p1[16], p2[16]; | |
401 | int err; | |
402 | ||
403 | memset(p1, 0, 16); | |
404 | ||
405 | /* p1 = pres || preq || _rat || _iat */ | |
943a732a JH |
406 | p1[0] = _iat; |
407 | p1[1] = _rat; | |
408 | memcpy(p1 + 2, preq, 7); | |
409 | memcpy(p1 + 9, pres, 7); | |
d22ef0bc AB |
410 | |
411 | /* p2 = padding || ia || ra */ | |
943a732a JH |
412 | memcpy(p2, ra, 6); |
413 | memcpy(p2 + 6, ia, 6); | |
414 | memset(p2 + 12, 0, 4); | |
d22ef0bc AB |
415 | |
416 | /* res = r XOR p1 */ | |
417 | u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); | |
418 | ||
419 | /* res = e(k, res) */ | |
e491eaf3 | 420 | err = smp_e(tfm_aes, k, res); |
d22ef0bc AB |
421 | if (err) { |
422 | BT_ERR("Encrypt data error"); | |
423 | return err; | |
424 | } | |
425 | ||
426 | /* res = res XOR p2 */ | |
427 | u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); | |
428 | ||
429 | /* res = e(k, res) */ | |
e491eaf3 | 430 | err = smp_e(tfm_aes, k, res); |
d22ef0bc AB |
431 | if (err) |
432 | BT_ERR("Encrypt data error"); | |
433 | ||
434 | return err; | |
435 | } | |
436 | ||
e491eaf3 JH |
437 | static int smp_s1(struct crypto_blkcipher *tfm_aes, u8 k[16], u8 r1[16], |
438 | u8 r2[16], u8 _r[16]) | |
d22ef0bc AB |
439 | { |
440 | int err; | |
441 | ||
442 | /* Just least significant octets from r1 and r2 are considered */ | |
943a732a JH |
443 | memcpy(_r, r2, 8); |
444 | memcpy(_r + 8, r1, 8); | |
d22ef0bc | 445 | |
e491eaf3 | 446 | err = smp_e(tfm_aes, k, _r); |
d22ef0bc AB |
447 | if (err) |
448 | BT_ERR("Encrypt data error"); | |
449 | ||
450 | return err; | |
451 | } | |
452 | ||
5d88cc73 | 453 | static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) |
eb492e01 | 454 | { |
5d88cc73 | 455 | struct l2cap_chan *chan = conn->smp; |
b68fda68 | 456 | struct smp_chan *smp; |
5d88cc73 JH |
457 | struct kvec iv[2]; |
458 | struct msghdr msg; | |
eb492e01 | 459 | |
5d88cc73 JH |
460 | if (!chan) |
461 | return; | |
eb492e01 | 462 | |
5d88cc73 | 463 | BT_DBG("code 0x%2.2x", code); |
eb492e01 | 464 | |
5d88cc73 JH |
465 | iv[0].iov_base = &code; |
466 | iv[0].iov_len = 1; | |
eb492e01 | 467 | |
5d88cc73 JH |
468 | iv[1].iov_base = data; |
469 | iv[1].iov_len = len; | |
eb492e01 | 470 | |
5d88cc73 | 471 | memset(&msg, 0, sizeof(msg)); |
eb492e01 | 472 | |
5d88cc73 JH |
473 | msg.msg_iov = (struct iovec *) &iv; |
474 | msg.msg_iovlen = 2; | |
eb492e01 | 475 | |
5d88cc73 | 476 | l2cap_chan_send(chan, &msg, 1 + len); |
e2dcd113 | 477 | |
b68fda68 JH |
478 | if (!chan->data) |
479 | return; | |
480 | ||
481 | smp = chan->data; | |
482 | ||
483 | cancel_delayed_work_sync(&smp->security_timer); | |
1b0921d6 | 484 | schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); |
eb492e01 AB |
485 | } |
486 | ||
d2eb9e10 | 487 | static u8 authreq_to_seclevel(u8 authreq) |
2b64d153 | 488 | { |
d2eb9e10 JH |
489 | if (authreq & SMP_AUTH_MITM) { |
490 | if (authreq & SMP_AUTH_SC) | |
491 | return BT_SECURITY_FIPS; | |
492 | else | |
493 | return BT_SECURITY_HIGH; | |
494 | } else { | |
2b64d153 | 495 | return BT_SECURITY_MEDIUM; |
d2eb9e10 | 496 | } |
2b64d153 BG |
497 | } |
498 | ||
499 | static __u8 seclevel_to_authreq(__u8 sec_level) | |
500 | { | |
501 | switch (sec_level) { | |
d2eb9e10 | 502 | case BT_SECURITY_FIPS: |
2b64d153 BG |
503 | case BT_SECURITY_HIGH: |
504 | return SMP_AUTH_MITM | SMP_AUTH_BONDING; | |
505 | case BT_SECURITY_MEDIUM: | |
506 | return SMP_AUTH_BONDING; | |
507 | default: | |
508 | return SMP_AUTH_NONE; | |
509 | } | |
510 | } | |
511 | ||
b8e66eac | 512 | static void build_pairing_cmd(struct l2cap_conn *conn, |
f1560463 MH |
513 | struct smp_cmd_pairing *req, |
514 | struct smp_cmd_pairing *rsp, __u8 authreq) | |
b8e66eac | 515 | { |
5d88cc73 JH |
516 | struct l2cap_chan *chan = conn->smp; |
517 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
518 | struct hci_conn *hcon = conn->hcon; |
519 | struct hci_dev *hdev = hcon->hdev; | |
520 | u8 local_dist = 0, remote_dist = 0; | |
54790f73 | 521 | |
b6ae8457 | 522 | if (test_bit(HCI_BONDABLE, &conn->hcon->hdev->dev_flags)) { |
7ee4ea36 MH |
523 | local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; |
524 | remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; | |
54790f73 | 525 | authreq |= SMP_AUTH_BONDING; |
2b64d153 BG |
526 | } else { |
527 | authreq &= ~SMP_AUTH_BONDING; | |
54790f73 VCG |
528 | } |
529 | ||
fd349c02 JH |
530 | if (test_bit(HCI_RPA_RESOLVING, &hdev->dev_flags)) |
531 | remote_dist |= SMP_DIST_ID_KEY; | |
532 | ||
863efaf2 JH |
533 | if (test_bit(HCI_PRIVACY, &hdev->dev_flags)) |
534 | local_dist |= SMP_DIST_ID_KEY; | |
535 | ||
df8e1a4c JH |
536 | if (test_bit(HCI_SC_ENABLED, &hdev->dev_flags)) { |
537 | if ((authreq & SMP_AUTH_SC) && | |
538 | test_bit(HCI_SSP_ENABLED, &hdev->dev_flags)) { | |
539 | local_dist |= SMP_DIST_LINK_KEY; | |
540 | remote_dist |= SMP_DIST_LINK_KEY; | |
541 | } | |
542 | } else { | |
543 | authreq &= ~SMP_AUTH_SC; | |
544 | } | |
545 | ||
54790f73 VCG |
546 | if (rsp == NULL) { |
547 | req->io_capability = conn->hcon->io_capability; | |
548 | req->oob_flag = SMP_OOB_NOT_PRESENT; | |
549 | req->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
fd349c02 JH |
550 | req->init_key_dist = local_dist; |
551 | req->resp_key_dist = remote_dist; | |
0edb14de | 552 | req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); |
fd349c02 JH |
553 | |
554 | smp->remote_key_dist = remote_dist; | |
54790f73 VCG |
555 | return; |
556 | } | |
557 | ||
558 | rsp->io_capability = conn->hcon->io_capability; | |
559 | rsp->oob_flag = SMP_OOB_NOT_PRESENT; | |
560 | rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
fd349c02 JH |
561 | rsp->init_key_dist = req->init_key_dist & remote_dist; |
562 | rsp->resp_key_dist = req->resp_key_dist & local_dist; | |
0edb14de | 563 | rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); |
fd349c02 JH |
564 | |
565 | smp->remote_key_dist = rsp->init_key_dist; | |
b8e66eac VCG |
566 | } |
567 | ||
3158c50c VCG |
568 | static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) |
569 | { | |
5d88cc73 JH |
570 | struct l2cap_chan *chan = conn->smp; |
571 | struct smp_chan *smp = chan->data; | |
1c1def09 | 572 | |
3158c50c | 573 | if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || |
f1560463 | 574 | (max_key_size < SMP_MIN_ENC_KEY_SIZE)) |
3158c50c VCG |
575 | return SMP_ENC_KEY_SIZE; |
576 | ||
f7aa611a | 577 | smp->enc_key_size = max_key_size; |
3158c50c VCG |
578 | |
579 | return 0; | |
580 | } | |
581 | ||
6f48e260 JH |
582 | static void smp_chan_destroy(struct l2cap_conn *conn) |
583 | { | |
584 | struct l2cap_chan *chan = conn->smp; | |
585 | struct smp_chan *smp = chan->data; | |
586 | bool complete; | |
587 | ||
588 | BUG_ON(!smp); | |
589 | ||
590 | cancel_delayed_work_sync(&smp->security_timer); | |
6f48e260 | 591 | |
6f48e260 JH |
592 | complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); |
593 | mgmt_smp_complete(conn->hcon, complete); | |
594 | ||
595 | kfree(smp->csrk); | |
596 | kfree(smp->slave_csrk); | |
597 | ||
598 | crypto_free_blkcipher(smp->tfm_aes); | |
407cecf6 | 599 | crypto_free_hash(smp->tfm_cmac); |
6f48e260 JH |
600 | |
601 | /* If pairing failed clean up any keys we might have */ | |
602 | if (!complete) { | |
603 | if (smp->ltk) { | |
970d0f1b JH |
604 | list_del_rcu(&smp->ltk->list); |
605 | kfree_rcu(smp->ltk, rcu); | |
6f48e260 JH |
606 | } |
607 | ||
608 | if (smp->slave_ltk) { | |
970d0f1b JH |
609 | list_del_rcu(&smp->slave_ltk->list); |
610 | kfree_rcu(smp->slave_ltk, rcu); | |
6f48e260 JH |
611 | } |
612 | ||
613 | if (smp->remote_irk) { | |
adae20cb JH |
614 | list_del_rcu(&smp->remote_irk->list); |
615 | kfree_rcu(smp->remote_irk, rcu); | |
6f48e260 JH |
616 | } |
617 | } | |
618 | ||
619 | chan->data = NULL; | |
620 | kfree(smp); | |
621 | hci_conn_drop(conn->hcon); | |
622 | } | |
623 | ||
84794e11 | 624 | static void smp_failure(struct l2cap_conn *conn, u8 reason) |
4f957a76 | 625 | { |
bab73cb6 | 626 | struct hci_conn *hcon = conn->hcon; |
b68fda68 | 627 | struct l2cap_chan *chan = conn->smp; |
bab73cb6 | 628 | |
84794e11 | 629 | if (reason) |
4f957a76 | 630 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), |
f1560463 | 631 | &reason); |
4f957a76 | 632 | |
ce39fb4e | 633 | clear_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags); |
e1e930f5 | 634 | mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); |
f1c09c07 | 635 | |
fc75cc86 | 636 | if (chan->data) |
f1c09c07 | 637 | smp_chan_destroy(conn); |
4f957a76 BG |
638 | } |
639 | ||
2b64d153 BG |
640 | #define JUST_WORKS 0x00 |
641 | #define JUST_CFM 0x01 | |
642 | #define REQ_PASSKEY 0x02 | |
643 | #define CFM_PASSKEY 0x03 | |
644 | #define REQ_OOB 0x04 | |
645 | #define OVERLAP 0xFF | |
646 | ||
647 | static const u8 gen_method[5][5] = { | |
648 | { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, | |
649 | { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, | |
650 | { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, | |
651 | { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, | |
652 | { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, | |
653 | }; | |
654 | ||
581370cc JH |
655 | static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) |
656 | { | |
2bcd4003 JH |
657 | /* If either side has unknown io_caps, use JUST_CFM (which gets |
658 | * converted later to JUST_WORKS if we're initiators. | |
659 | */ | |
581370cc JH |
660 | if (local_io > SMP_IO_KEYBOARD_DISPLAY || |
661 | remote_io > SMP_IO_KEYBOARD_DISPLAY) | |
2bcd4003 | 662 | return JUST_CFM; |
581370cc JH |
663 | |
664 | return gen_method[remote_io][local_io]; | |
665 | } | |
666 | ||
2b64d153 BG |
667 | static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, |
668 | u8 local_io, u8 remote_io) | |
669 | { | |
670 | struct hci_conn *hcon = conn->hcon; | |
5d88cc73 JH |
671 | struct l2cap_chan *chan = conn->smp; |
672 | struct smp_chan *smp = chan->data; | |
2b64d153 BG |
673 | u8 method; |
674 | u32 passkey = 0; | |
675 | int ret = 0; | |
676 | ||
677 | /* Initialize key for JUST WORKS */ | |
678 | memset(smp->tk, 0, sizeof(smp->tk)); | |
4a74d658 | 679 | clear_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
680 | |
681 | BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); | |
682 | ||
2bcd4003 JH |
683 | /* If neither side wants MITM, either "just" confirm an incoming |
684 | * request or use just-works for outgoing ones. The JUST_CFM | |
685 | * will be converted to JUST_WORKS if necessary later in this | |
686 | * function. If either side has MITM look up the method from the | |
687 | * table. | |
688 | */ | |
581370cc | 689 | if (!(auth & SMP_AUTH_MITM)) |
2bcd4003 | 690 | method = JUST_CFM; |
2b64d153 | 691 | else |
581370cc | 692 | method = get_auth_method(smp, local_io, remote_io); |
2b64d153 | 693 | |
a82505c7 | 694 | /* Don't confirm locally initiated pairing attempts */ |
4a74d658 | 695 | if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) |
a82505c7 JH |
696 | method = JUST_WORKS; |
697 | ||
02f3e254 JH |
698 | /* Don't bother user space with no IO capabilities */ |
699 | if (method == JUST_CFM && hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) | |
700 | method = JUST_WORKS; | |
701 | ||
2b64d153 BG |
702 | /* If Just Works, Continue with Zero TK */ |
703 | if (method == JUST_WORKS) { | |
4a74d658 | 704 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
705 | return 0; |
706 | } | |
707 | ||
708 | /* Not Just Works/Confirm results in MITM Authentication */ | |
5eb596f5 | 709 | if (method != JUST_CFM) { |
4a74d658 | 710 | set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); |
5eb596f5 JH |
711 | if (hcon->pending_sec_level < BT_SECURITY_HIGH) |
712 | hcon->pending_sec_level = BT_SECURITY_HIGH; | |
713 | } | |
2b64d153 BG |
714 | |
715 | /* If both devices have Keyoard-Display I/O, the master | |
716 | * Confirms and the slave Enters the passkey. | |
717 | */ | |
718 | if (method == OVERLAP) { | |
40bef302 | 719 | if (hcon->role == HCI_ROLE_MASTER) |
2b64d153 BG |
720 | method = CFM_PASSKEY; |
721 | else | |
722 | method = REQ_PASSKEY; | |
723 | } | |
724 | ||
01ad34d2 | 725 | /* Generate random passkey. */ |
2b64d153 | 726 | if (method == CFM_PASSKEY) { |
943a732a | 727 | memset(smp->tk, 0, sizeof(smp->tk)); |
2b64d153 BG |
728 | get_random_bytes(&passkey, sizeof(passkey)); |
729 | passkey %= 1000000; | |
943a732a | 730 | put_unaligned_le32(passkey, smp->tk); |
2b64d153 | 731 | BT_DBG("PassKey: %d", passkey); |
4a74d658 | 732 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
733 | } |
734 | ||
2b64d153 | 735 | if (method == REQ_PASSKEY) |
ce39fb4e | 736 | ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, |
272d90df | 737 | hcon->type, hcon->dst_type); |
4eb65e66 JH |
738 | else if (method == JUST_CFM) |
739 | ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, | |
740 | hcon->type, hcon->dst_type, | |
741 | passkey, 1); | |
2b64d153 | 742 | else |
01ad34d2 | 743 | ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, |
272d90df | 744 | hcon->type, hcon->dst_type, |
39adbffe | 745 | passkey, 0); |
2b64d153 | 746 | |
2b64d153 BG |
747 | return ret; |
748 | } | |
749 | ||
1cc61144 | 750 | static u8 smp_confirm(struct smp_chan *smp) |
8aab4757 | 751 | { |
8aab4757 | 752 | struct l2cap_conn *conn = smp->conn; |
8aab4757 VCG |
753 | struct smp_cmd_pairing_confirm cp; |
754 | int ret; | |
8aab4757 VCG |
755 | |
756 | BT_DBG("conn %p", conn); | |
757 | ||
e491eaf3 | 758 | ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp, |
b1cd5fd9 | 759 | conn->hcon->init_addr_type, &conn->hcon->init_addr, |
943a732a JH |
760 | conn->hcon->resp_addr_type, &conn->hcon->resp_addr, |
761 | cp.confirm_val); | |
1cc61144 JH |
762 | if (ret) |
763 | return SMP_UNSPECIFIED; | |
8aab4757 | 764 | |
4a74d658 | 765 | clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
2b64d153 | 766 | |
8aab4757 VCG |
767 | smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); |
768 | ||
b28b4943 JH |
769 | if (conn->hcon->out) |
770 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); | |
771 | else | |
772 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); | |
773 | ||
1cc61144 | 774 | return 0; |
8aab4757 VCG |
775 | } |
776 | ||
861580a9 | 777 | static u8 smp_random(struct smp_chan *smp) |
8aab4757 | 778 | { |
8aab4757 VCG |
779 | struct l2cap_conn *conn = smp->conn; |
780 | struct hci_conn *hcon = conn->hcon; | |
861580a9 | 781 | u8 confirm[16]; |
8aab4757 VCG |
782 | int ret; |
783 | ||
ec70f36f | 784 | if (IS_ERR_OR_NULL(smp->tfm_aes)) |
861580a9 | 785 | return SMP_UNSPECIFIED; |
8aab4757 VCG |
786 | |
787 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); | |
788 | ||
e491eaf3 | 789 | ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp, |
b1cd5fd9 | 790 | hcon->init_addr_type, &hcon->init_addr, |
943a732a | 791 | hcon->resp_addr_type, &hcon->resp_addr, confirm); |
861580a9 JH |
792 | if (ret) |
793 | return SMP_UNSPECIFIED; | |
8aab4757 | 794 | |
8aab4757 VCG |
795 | if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) { |
796 | BT_ERR("Pairing failed (confirmation values mismatch)"); | |
861580a9 | 797 | return SMP_CONFIRM_FAILED; |
8aab4757 VCG |
798 | } |
799 | ||
800 | if (hcon->out) { | |
fe39c7b2 MH |
801 | u8 stk[16]; |
802 | __le64 rand = 0; | |
803 | __le16 ediv = 0; | |
8aab4757 | 804 | |
e491eaf3 | 805 | smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk); |
8aab4757 | 806 | |
f7aa611a | 807 | memset(stk + smp->enc_key_size, 0, |
04124681 | 808 | SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); |
8aab4757 | 809 | |
861580a9 JH |
810 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) |
811 | return SMP_UNSPECIFIED; | |
8aab4757 VCG |
812 | |
813 | hci_le_start_enc(hcon, ediv, rand, stk); | |
f7aa611a | 814 | hcon->enc_key_size = smp->enc_key_size; |
fe59a05f | 815 | set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); |
8aab4757 | 816 | } else { |
fff3490f | 817 | u8 stk[16], auth; |
fe39c7b2 MH |
818 | __le64 rand = 0; |
819 | __le16 ediv = 0; | |
8aab4757 | 820 | |
943a732a JH |
821 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), |
822 | smp->prnd); | |
8aab4757 | 823 | |
e491eaf3 | 824 | smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk); |
8aab4757 | 825 | |
f7aa611a | 826 | memset(stk + smp->enc_key_size, 0, |
f1560463 | 827 | SMP_MAX_ENC_KEY_SIZE - smp->enc_key_size); |
8aab4757 | 828 | |
fff3490f JH |
829 | if (hcon->pending_sec_level == BT_SECURITY_HIGH) |
830 | auth = 1; | |
831 | else | |
832 | auth = 0; | |
833 | ||
7d5843b7 JH |
834 | /* Even though there's no _SLAVE suffix this is the |
835 | * slave STK we're adding for later lookup (the master | |
836 | * STK never needs to be stored). | |
837 | */ | |
ce39fb4e | 838 | hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, |
2ceba539 | 839 | SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); |
8aab4757 VCG |
840 | } |
841 | ||
861580a9 | 842 | return 0; |
8aab4757 VCG |
843 | } |
844 | ||
44f1a7ab JH |
845 | static void smp_notify_keys(struct l2cap_conn *conn) |
846 | { | |
847 | struct l2cap_chan *chan = conn->smp; | |
848 | struct smp_chan *smp = chan->data; | |
849 | struct hci_conn *hcon = conn->hcon; | |
850 | struct hci_dev *hdev = hcon->hdev; | |
851 | struct smp_cmd_pairing *req = (void *) &smp->preq[1]; | |
852 | struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; | |
853 | bool persistent; | |
854 | ||
855 | if (smp->remote_irk) { | |
856 | mgmt_new_irk(hdev, smp->remote_irk); | |
857 | /* Now that user space can be considered to know the | |
858 | * identity address track the connection based on it | |
859 | * from now on. | |
860 | */ | |
861 | bacpy(&hcon->dst, &smp->remote_irk->bdaddr); | |
862 | hcon->dst_type = smp->remote_irk->addr_type; | |
f3d82d0c | 863 | queue_work(hdev->workqueue, &conn->id_addr_update_work); |
44f1a7ab JH |
864 | |
865 | /* When receiving an indentity resolving key for | |
866 | * a remote device that does not use a resolvable | |
867 | * private address, just remove the key so that | |
868 | * it is possible to use the controller white | |
869 | * list for scanning. | |
870 | * | |
871 | * Userspace will have been told to not store | |
872 | * this key at this point. So it is safe to | |
873 | * just remove it. | |
874 | */ | |
875 | if (!bacmp(&smp->remote_irk->rpa, BDADDR_ANY)) { | |
adae20cb JH |
876 | list_del_rcu(&smp->remote_irk->list); |
877 | kfree_rcu(smp->remote_irk, rcu); | |
44f1a7ab JH |
878 | smp->remote_irk = NULL; |
879 | } | |
880 | } | |
881 | ||
882 | /* The LTKs and CSRKs should be persistent only if both sides | |
883 | * had the bonding bit set in their authentication requests. | |
884 | */ | |
885 | persistent = !!((req->auth_req & rsp->auth_req) & SMP_AUTH_BONDING); | |
886 | ||
887 | if (smp->csrk) { | |
888 | smp->csrk->bdaddr_type = hcon->dst_type; | |
889 | bacpy(&smp->csrk->bdaddr, &hcon->dst); | |
890 | mgmt_new_csrk(hdev, smp->csrk, persistent); | |
891 | } | |
892 | ||
893 | if (smp->slave_csrk) { | |
894 | smp->slave_csrk->bdaddr_type = hcon->dst_type; | |
895 | bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); | |
896 | mgmt_new_csrk(hdev, smp->slave_csrk, persistent); | |
897 | } | |
898 | ||
899 | if (smp->ltk) { | |
900 | smp->ltk->bdaddr_type = hcon->dst_type; | |
901 | bacpy(&smp->ltk->bdaddr, &hcon->dst); | |
902 | mgmt_new_ltk(hdev, smp->ltk, persistent); | |
903 | } | |
904 | ||
905 | if (smp->slave_ltk) { | |
906 | smp->slave_ltk->bdaddr_type = hcon->dst_type; | |
907 | bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); | |
908 | mgmt_new_ltk(hdev, smp->slave_ltk, persistent); | |
909 | } | |
910 | } | |
911 | ||
b28b4943 JH |
912 | static void smp_allow_key_dist(struct smp_chan *smp) |
913 | { | |
914 | /* Allow the first expected phase 3 PDU. The rest of the PDUs | |
915 | * will be allowed in each PDU handler to ensure we receive | |
916 | * them in the correct order. | |
917 | */ | |
918 | if (smp->remote_key_dist & SMP_DIST_ENC_KEY) | |
919 | SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); | |
920 | else if (smp->remote_key_dist & SMP_DIST_ID_KEY) | |
921 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); | |
922 | else if (smp->remote_key_dist & SMP_DIST_SIGN) | |
923 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
924 | } | |
925 | ||
d6268e86 | 926 | static void smp_distribute_keys(struct smp_chan *smp) |
44f1a7ab JH |
927 | { |
928 | struct smp_cmd_pairing *req, *rsp; | |
86d1407c | 929 | struct l2cap_conn *conn = smp->conn; |
44f1a7ab JH |
930 | struct hci_conn *hcon = conn->hcon; |
931 | struct hci_dev *hdev = hcon->hdev; | |
932 | __u8 *keydist; | |
933 | ||
934 | BT_DBG("conn %p", conn); | |
935 | ||
44f1a7ab JH |
936 | rsp = (void *) &smp->prsp[1]; |
937 | ||
938 | /* The responder sends its keys first */ | |
b28b4943 JH |
939 | if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { |
940 | smp_allow_key_dist(smp); | |
86d1407c | 941 | return; |
b28b4943 | 942 | } |
44f1a7ab JH |
943 | |
944 | req = (void *) &smp->preq[1]; | |
945 | ||
946 | if (hcon->out) { | |
947 | keydist = &rsp->init_key_dist; | |
948 | *keydist &= req->init_key_dist; | |
949 | } else { | |
950 | keydist = &rsp->resp_key_dist; | |
951 | *keydist &= req->resp_key_dist; | |
952 | } | |
953 | ||
954 | BT_DBG("keydist 0x%x", *keydist); | |
955 | ||
956 | if (*keydist & SMP_DIST_ENC_KEY) { | |
957 | struct smp_cmd_encrypt_info enc; | |
958 | struct smp_cmd_master_ident ident; | |
959 | struct smp_ltk *ltk; | |
960 | u8 authenticated; | |
961 | __le16 ediv; | |
962 | __le64 rand; | |
963 | ||
964 | get_random_bytes(enc.ltk, sizeof(enc.ltk)); | |
965 | get_random_bytes(&ediv, sizeof(ediv)); | |
966 | get_random_bytes(&rand, sizeof(rand)); | |
967 | ||
968 | smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); | |
969 | ||
970 | authenticated = hcon->sec_level == BT_SECURITY_HIGH; | |
971 | ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, | |
972 | SMP_LTK_SLAVE, authenticated, enc.ltk, | |
973 | smp->enc_key_size, ediv, rand); | |
974 | smp->slave_ltk = ltk; | |
975 | ||
976 | ident.ediv = ediv; | |
977 | ident.rand = rand; | |
978 | ||
979 | smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); | |
980 | ||
981 | *keydist &= ~SMP_DIST_ENC_KEY; | |
982 | } | |
983 | ||
984 | if (*keydist & SMP_DIST_ID_KEY) { | |
985 | struct smp_cmd_ident_addr_info addrinfo; | |
986 | struct smp_cmd_ident_info idinfo; | |
987 | ||
988 | memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); | |
989 | ||
990 | smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); | |
991 | ||
992 | /* The hci_conn contains the local identity address | |
993 | * after the connection has been established. | |
994 | * | |
995 | * This is true even when the connection has been | |
996 | * established using a resolvable random address. | |
997 | */ | |
998 | bacpy(&addrinfo.bdaddr, &hcon->src); | |
999 | addrinfo.addr_type = hcon->src_type; | |
1000 | ||
1001 | smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), | |
1002 | &addrinfo); | |
1003 | ||
1004 | *keydist &= ~SMP_DIST_ID_KEY; | |
1005 | } | |
1006 | ||
1007 | if (*keydist & SMP_DIST_SIGN) { | |
1008 | struct smp_cmd_sign_info sign; | |
1009 | struct smp_csrk *csrk; | |
1010 | ||
1011 | /* Generate a new random key */ | |
1012 | get_random_bytes(sign.csrk, sizeof(sign.csrk)); | |
1013 | ||
1014 | csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); | |
1015 | if (csrk) { | |
1016 | csrk->master = 0x00; | |
1017 | memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); | |
1018 | } | |
1019 | smp->slave_csrk = csrk; | |
1020 | ||
1021 | smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); | |
1022 | ||
1023 | *keydist &= ~SMP_DIST_SIGN; | |
1024 | } | |
1025 | ||
1026 | /* If there are still keys to be received wait for them */ | |
b28b4943 JH |
1027 | if (smp->remote_key_dist & KEY_DIST_MASK) { |
1028 | smp_allow_key_dist(smp); | |
86d1407c | 1029 | return; |
b28b4943 | 1030 | } |
44f1a7ab | 1031 | |
44f1a7ab JH |
1032 | set_bit(SMP_FLAG_COMPLETE, &smp->flags); |
1033 | smp_notify_keys(conn); | |
1034 | ||
1035 | smp_chan_destroy(conn); | |
44f1a7ab JH |
1036 | } |
1037 | ||
b68fda68 JH |
1038 | static void smp_timeout(struct work_struct *work) |
1039 | { | |
1040 | struct smp_chan *smp = container_of(work, struct smp_chan, | |
1041 | security_timer.work); | |
1042 | struct l2cap_conn *conn = smp->conn; | |
1043 | ||
1044 | BT_DBG("conn %p", conn); | |
1045 | ||
1e91c29e | 1046 | hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); |
b68fda68 JH |
1047 | } |
1048 | ||
8aab4757 VCG |
1049 | static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) |
1050 | { | |
5d88cc73 | 1051 | struct l2cap_chan *chan = conn->smp; |
8aab4757 VCG |
1052 | struct smp_chan *smp; |
1053 | ||
f1560463 | 1054 | smp = kzalloc(sizeof(*smp), GFP_ATOMIC); |
fc75cc86 | 1055 | if (!smp) |
8aab4757 VCG |
1056 | return NULL; |
1057 | ||
6a7bd103 JH |
1058 | smp->tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, CRYPTO_ALG_ASYNC); |
1059 | if (IS_ERR(smp->tfm_aes)) { | |
1060 | BT_ERR("Unable to create ECB crypto context"); | |
1061 | kfree(smp); | |
1062 | return NULL; | |
1063 | } | |
1064 | ||
407cecf6 JH |
1065 | smp->tfm_cmac = crypto_alloc_hash("cmac(aes)", 0, CRYPTO_ALG_ASYNC); |
1066 | if (IS_ERR(smp->tfm_cmac)) { | |
1067 | BT_ERR("Unable to create CMAC crypto context"); | |
1068 | crypto_free_blkcipher(smp->tfm_aes); | |
1069 | kfree(smp); | |
1070 | return NULL; | |
1071 | } | |
1072 | ||
8aab4757 | 1073 | smp->conn = conn; |
5d88cc73 | 1074 | chan->data = smp; |
8aab4757 | 1075 | |
b28b4943 JH |
1076 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); |
1077 | ||
b68fda68 JH |
1078 | INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); |
1079 | ||
8aab4757 VCG |
1080 | hci_conn_hold(conn->hcon); |
1081 | ||
1082 | return smp; | |
1083 | } | |
1084 | ||
760b018b JH |
1085 | static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) |
1086 | { | |
1087 | struct hci_conn *hcon = smp->conn->hcon; | |
1088 | u8 *na, *nb, a[7], b[7]; | |
1089 | ||
1090 | if (hcon->out) { | |
1091 | na = smp->prnd; | |
1092 | nb = smp->rrnd; | |
1093 | } else { | |
1094 | na = smp->rrnd; | |
1095 | nb = smp->prnd; | |
1096 | } | |
1097 | ||
1098 | memcpy(a, &hcon->init_addr, 6); | |
1099 | memcpy(b, &hcon->resp_addr, 6); | |
1100 | a[6] = hcon->init_addr_type; | |
1101 | b[6] = hcon->resp_addr_type; | |
1102 | ||
1103 | return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); | |
1104 | } | |
1105 | ||
1106 | static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) | |
1107 | { | |
1108 | struct hci_conn *hcon = smp->conn->hcon; | |
1109 | struct smp_cmd_dhkey_check check; | |
1110 | u8 a[7], b[7], *local_addr, *remote_addr; | |
1111 | u8 io_cap[3], r[16]; | |
1112 | ||
1113 | switch (mgmt_op) { | |
1114 | case MGMT_OP_USER_PASSKEY_NEG_REPLY: | |
1115 | smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); | |
1116 | return 0; | |
1117 | case MGMT_OP_USER_CONFIRM_NEG_REPLY: | |
1118 | smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); | |
1119 | return 0; | |
1120 | } | |
1121 | ||
1122 | memcpy(a, &hcon->init_addr, 6); | |
1123 | memcpy(b, &hcon->resp_addr, 6); | |
1124 | a[6] = hcon->init_addr_type; | |
1125 | b[6] = hcon->resp_addr_type; | |
1126 | ||
1127 | if (hcon->out) { | |
1128 | local_addr = a; | |
1129 | remote_addr = b; | |
1130 | memcpy(io_cap, &smp->preq[1], 3); | |
1131 | } else { | |
1132 | local_addr = b; | |
1133 | remote_addr = a; | |
1134 | memcpy(io_cap, &smp->prsp[1], 3); | |
1135 | } | |
1136 | ||
1137 | memcpy(r, &passkey, sizeof(passkey)); | |
1138 | memset(r + sizeof(passkey), 0, sizeof(r) - sizeof(passkey)); | |
1139 | ||
1140 | smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, | |
1141 | local_addr, remote_addr, check.e); | |
1142 | ||
1143 | smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); | |
1144 | ||
1145 | return 0; | |
1146 | } | |
1147 | ||
2b64d153 BG |
1148 | int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) |
1149 | { | |
b10e8017 | 1150 | struct l2cap_conn *conn = hcon->l2cap_data; |
5d88cc73 | 1151 | struct l2cap_chan *chan; |
2b64d153 BG |
1152 | struct smp_chan *smp; |
1153 | u32 value; | |
fc75cc86 | 1154 | int err; |
2b64d153 BG |
1155 | |
1156 | BT_DBG(""); | |
1157 | ||
fc75cc86 | 1158 | if (!conn) |
2b64d153 BG |
1159 | return -ENOTCONN; |
1160 | ||
5d88cc73 JH |
1161 | chan = conn->smp; |
1162 | if (!chan) | |
1163 | return -ENOTCONN; | |
1164 | ||
fc75cc86 JH |
1165 | l2cap_chan_lock(chan); |
1166 | if (!chan->data) { | |
1167 | err = -ENOTCONN; | |
1168 | goto unlock; | |
1169 | } | |
1170 | ||
5d88cc73 | 1171 | smp = chan->data; |
2b64d153 | 1172 | |
760b018b JH |
1173 | if (test_bit(SMP_FLAG_SC, &smp->flags)) { |
1174 | err = sc_user_reply(smp, mgmt_op, passkey); | |
1175 | goto unlock; | |
1176 | } | |
1177 | ||
2b64d153 BG |
1178 | switch (mgmt_op) { |
1179 | case MGMT_OP_USER_PASSKEY_REPLY: | |
1180 | value = le32_to_cpu(passkey); | |
943a732a | 1181 | memset(smp->tk, 0, sizeof(smp->tk)); |
2b64d153 | 1182 | BT_DBG("PassKey: %d", value); |
943a732a | 1183 | put_unaligned_le32(value, smp->tk); |
2b64d153 BG |
1184 | /* Fall Through */ |
1185 | case MGMT_OP_USER_CONFIRM_REPLY: | |
4a74d658 | 1186 | set_bit(SMP_FLAG_TK_VALID, &smp->flags); |
2b64d153 BG |
1187 | break; |
1188 | case MGMT_OP_USER_PASSKEY_NEG_REPLY: | |
1189 | case MGMT_OP_USER_CONFIRM_NEG_REPLY: | |
84794e11 | 1190 | smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); |
fc75cc86 JH |
1191 | err = 0; |
1192 | goto unlock; | |
2b64d153 | 1193 | default: |
84794e11 | 1194 | smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); |
fc75cc86 JH |
1195 | err = -EOPNOTSUPP; |
1196 | goto unlock; | |
2b64d153 BG |
1197 | } |
1198 | ||
fc75cc86 JH |
1199 | err = 0; |
1200 | ||
2b64d153 | 1201 | /* If it is our turn to send Pairing Confirm, do so now */ |
1cc61144 JH |
1202 | if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { |
1203 | u8 rsp = smp_confirm(smp); | |
1204 | if (rsp) | |
1205 | smp_failure(conn, rsp); | |
1206 | } | |
2b64d153 | 1207 | |
fc75cc86 JH |
1208 | unlock: |
1209 | l2cap_chan_unlock(chan); | |
1210 | return err; | |
2b64d153 BG |
1211 | } |
1212 | ||
da85e5e5 | 1213 | static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1214 | { |
3158c50c | 1215 | struct smp_cmd_pairing rsp, *req = (void *) skb->data; |
fc75cc86 | 1216 | struct l2cap_chan *chan = conn->smp; |
b3c6410b | 1217 | struct hci_dev *hdev = conn->hcon->hdev; |
8aab4757 | 1218 | struct smp_chan *smp; |
c7262e71 | 1219 | u8 key_size, auth, sec_level; |
8aab4757 | 1220 | int ret; |
88ba43b6 AB |
1221 | |
1222 | BT_DBG("conn %p", conn); | |
1223 | ||
c46b98be | 1224 | if (skb->len < sizeof(*req)) |
38e4a915 | 1225 | return SMP_INVALID_PARAMS; |
c46b98be | 1226 | |
40bef302 | 1227 | if (conn->hcon->role != HCI_ROLE_SLAVE) |
2b64d153 BG |
1228 | return SMP_CMD_NOTSUPP; |
1229 | ||
fc75cc86 | 1230 | if (!chan->data) |
8aab4757 | 1231 | smp = smp_chan_create(conn); |
fc75cc86 | 1232 | else |
5d88cc73 | 1233 | smp = chan->data; |
8aab4757 | 1234 | |
d08fd0e7 AE |
1235 | if (!smp) |
1236 | return SMP_UNSPECIFIED; | |
d26a2345 | 1237 | |
c05b9339 | 1238 | /* We didn't start the pairing, so match remote */ |
0edb14de | 1239 | auth = req->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 1240 | |
b6ae8457 | 1241 | if (!test_bit(HCI_BONDABLE, &hdev->dev_flags) && |
c05b9339 | 1242 | (auth & SMP_AUTH_BONDING)) |
b3c6410b JH |
1243 | return SMP_PAIRING_NOTSUPP; |
1244 | ||
1c1def09 VCG |
1245 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
1246 | memcpy(&smp->preq[1], req, sizeof(*req)); | |
3158c50c | 1247 | skb_pull(skb, sizeof(*req)); |
88ba43b6 | 1248 | |
5be5e275 | 1249 | if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) |
1afc2a1a JH |
1250 | sec_level = BT_SECURITY_MEDIUM; |
1251 | else | |
1252 | sec_level = authreq_to_seclevel(auth); | |
1253 | ||
c7262e71 JH |
1254 | if (sec_level > conn->hcon->pending_sec_level) |
1255 | conn->hcon->pending_sec_level = sec_level; | |
fdde0a26 | 1256 | |
49c922bb | 1257 | /* If we need MITM check that it can be achieved */ |
2ed8f65c JH |
1258 | if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { |
1259 | u8 method; | |
1260 | ||
1261 | method = get_auth_method(smp, conn->hcon->io_capability, | |
1262 | req->io_capability); | |
1263 | if (method == JUST_WORKS || method == JUST_CFM) | |
1264 | return SMP_AUTH_REQUIREMENTS; | |
1265 | } | |
1266 | ||
2b64d153 | 1267 | build_pairing_cmd(conn, req, &rsp, auth); |
3158c50c | 1268 | |
65668776 JH |
1269 | if (rsp.auth_req & SMP_AUTH_SC) |
1270 | set_bit(SMP_FLAG_SC, &smp->flags); | |
1271 | ||
3158c50c VCG |
1272 | key_size = min(req->max_key_size, rsp.max_key_size); |
1273 | if (check_enc_key_size(conn, key_size)) | |
1274 | return SMP_ENC_KEY_SIZE; | |
88ba43b6 | 1275 | |
e84a6b13 | 1276 | get_random_bytes(smp->prnd, sizeof(smp->prnd)); |
8aab4757 | 1277 | |
1c1def09 VCG |
1278 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
1279 | memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); | |
f01ead31 | 1280 | |
3158c50c | 1281 | smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); |
3b19146d JH |
1282 | |
1283 | clear_bit(SMP_FLAG_INITIATOR, &smp->flags); | |
1284 | ||
1285 | if (test_bit(SMP_FLAG_SC, &smp->flags)) { | |
1286 | SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); | |
1287 | /* Clear bits which are generated but not distributed */ | |
1288 | smp->remote_key_dist &= ~SMP_SC_NO_DIST; | |
1289 | /* Wait for Public Key from Initiating Device */ | |
1290 | return 0; | |
1291 | } else { | |
1292 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); | |
1293 | } | |
da85e5e5 | 1294 | |
2b64d153 BG |
1295 | /* Request setup of TK */ |
1296 | ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); | |
1297 | if (ret) | |
1298 | return SMP_UNSPECIFIED; | |
1299 | ||
da85e5e5 | 1300 | return 0; |
88ba43b6 AB |
1301 | } |
1302 | ||
3b19146d JH |
1303 | static u8 sc_send_public_key(struct smp_chan *smp) |
1304 | { | |
1305 | BT_DBG(""); | |
1306 | ||
1307 | /* Generate local key pair for Secure Connections */ | |
1308 | if (!ecc_make_key(smp->local_pk, smp->local_sk)) | |
1309 | return SMP_UNSPECIFIED; | |
1310 | ||
1311 | BT_DBG("Local Public Key X: %32phN", smp->local_pk); | |
1312 | BT_DBG("Local Public Key Y: %32phN", &smp->local_pk[32]); | |
1313 | BT_DBG("Local Private Key: %32phN", smp->local_sk); | |
1314 | ||
1315 | smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); | |
1316 | ||
1317 | return 0; | |
1318 | } | |
1319 | ||
da85e5e5 | 1320 | static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1321 | { |
3158c50c | 1322 | struct smp_cmd_pairing *req, *rsp = (void *) skb->data; |
5d88cc73 JH |
1323 | struct l2cap_chan *chan = conn->smp; |
1324 | struct smp_chan *smp = chan->data; | |
0edb14de | 1325 | struct hci_dev *hdev = conn->hcon->hdev; |
3a7dbfb8 | 1326 | u8 key_size, auth; |
7d24ddcc | 1327 | int ret; |
88ba43b6 AB |
1328 | |
1329 | BT_DBG("conn %p", conn); | |
1330 | ||
c46b98be | 1331 | if (skb->len < sizeof(*rsp)) |
38e4a915 | 1332 | return SMP_INVALID_PARAMS; |
c46b98be | 1333 | |
40bef302 | 1334 | if (conn->hcon->role != HCI_ROLE_MASTER) |
2b64d153 BG |
1335 | return SMP_CMD_NOTSUPP; |
1336 | ||
3158c50c VCG |
1337 | skb_pull(skb, sizeof(*rsp)); |
1338 | ||
1c1def09 | 1339 | req = (void *) &smp->preq[1]; |
da85e5e5 | 1340 | |
3158c50c VCG |
1341 | key_size = min(req->max_key_size, rsp->max_key_size); |
1342 | if (check_enc_key_size(conn, key_size)) | |
1343 | return SMP_ENC_KEY_SIZE; | |
1344 | ||
0edb14de | 1345 | auth = rsp->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 1346 | |
65668776 JH |
1347 | if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) |
1348 | set_bit(SMP_FLAG_SC, &smp->flags); | |
d2eb9e10 JH |
1349 | else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) |
1350 | conn->hcon->pending_sec_level = BT_SECURITY_HIGH; | |
65668776 | 1351 | |
49c922bb | 1352 | /* If we need MITM check that it can be achieved */ |
2ed8f65c JH |
1353 | if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { |
1354 | u8 method; | |
1355 | ||
1356 | method = get_auth_method(smp, req->io_capability, | |
1357 | rsp->io_capability); | |
1358 | if (method == JUST_WORKS || method == JUST_CFM) | |
1359 | return SMP_AUTH_REQUIREMENTS; | |
1360 | } | |
1361 | ||
e84a6b13 | 1362 | get_random_bytes(smp->prnd, sizeof(smp->prnd)); |
7d24ddcc | 1363 | |
8aab4757 VCG |
1364 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
1365 | memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); | |
7d24ddcc | 1366 | |
fdcc4bec JH |
1367 | /* Update remote key distribution in case the remote cleared |
1368 | * some bits that we had enabled in our request. | |
1369 | */ | |
1370 | smp->remote_key_dist &= rsp->resp_key_dist; | |
1371 | ||
3b19146d JH |
1372 | if (test_bit(SMP_FLAG_SC, &smp->flags)) { |
1373 | /* Clear bits which are generated but not distributed */ | |
1374 | smp->remote_key_dist &= ~SMP_SC_NO_DIST; | |
1375 | SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); | |
1376 | return sc_send_public_key(smp); | |
1377 | } | |
1378 | ||
c05b9339 | 1379 | auth |= req->auth_req; |
2b64d153 | 1380 | |
476585ec | 1381 | ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); |
2b64d153 BG |
1382 | if (ret) |
1383 | return SMP_UNSPECIFIED; | |
1384 | ||
4a74d658 | 1385 | set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
2b64d153 BG |
1386 | |
1387 | /* Can't compose response until we have been confirmed */ | |
4a74d658 | 1388 | if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) |
1cc61144 | 1389 | return smp_confirm(smp); |
da85e5e5 VCG |
1390 | |
1391 | return 0; | |
88ba43b6 AB |
1392 | } |
1393 | ||
dcee2b32 JH |
1394 | static u8 sc_check_confirm(struct smp_chan *smp) |
1395 | { | |
1396 | struct l2cap_conn *conn = smp->conn; | |
1397 | ||
1398 | BT_DBG(""); | |
1399 | ||
1400 | /* Public Key exchange must happen before any other steps */ | |
1401 | if (!test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) | |
1402 | return SMP_UNSPECIFIED; | |
1403 | ||
1404 | if (conn->hcon->out) { | |
1405 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), | |
1406 | smp->prnd); | |
1407 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); | |
1408 | } | |
1409 | ||
1410 | return 0; | |
1411 | } | |
1412 | ||
da85e5e5 | 1413 | static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1414 | { |
5d88cc73 JH |
1415 | struct l2cap_chan *chan = conn->smp; |
1416 | struct smp_chan *smp = chan->data; | |
7d24ddcc | 1417 | |
88ba43b6 AB |
1418 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); |
1419 | ||
c46b98be | 1420 | if (skb->len < sizeof(smp->pcnf)) |
38e4a915 | 1421 | return SMP_INVALID_PARAMS; |
c46b98be | 1422 | |
1c1def09 VCG |
1423 | memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); |
1424 | skb_pull(skb, sizeof(smp->pcnf)); | |
88ba43b6 | 1425 | |
dcee2b32 JH |
1426 | if (test_bit(SMP_FLAG_SC, &smp->flags)) |
1427 | return sc_check_confirm(smp); | |
1428 | ||
b28b4943 | 1429 | if (conn->hcon->out) { |
943a732a JH |
1430 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), |
1431 | smp->prnd); | |
b28b4943 JH |
1432 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); |
1433 | return 0; | |
1434 | } | |
1435 | ||
1436 | if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) | |
1cc61144 | 1437 | return smp_confirm(smp); |
943a732a | 1438 | else |
4a74d658 | 1439 | set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); |
da85e5e5 VCG |
1440 | |
1441 | return 0; | |
88ba43b6 AB |
1442 | } |
1443 | ||
da85e5e5 | 1444 | static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 1445 | { |
5d88cc73 JH |
1446 | struct l2cap_chan *chan = conn->smp; |
1447 | struct smp_chan *smp = chan->data; | |
191dc7fe JH |
1448 | struct hci_conn *hcon = conn->hcon; |
1449 | u8 *pkax, *pkbx, *na, *nb; | |
1450 | u32 passkey; | |
1451 | int err; | |
7d24ddcc | 1452 | |
8aab4757 | 1453 | BT_DBG("conn %p", conn); |
3158c50c | 1454 | |
c46b98be | 1455 | if (skb->len < sizeof(smp->rrnd)) |
38e4a915 | 1456 | return SMP_INVALID_PARAMS; |
c46b98be | 1457 | |
943a732a | 1458 | memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); |
8aab4757 | 1459 | skb_pull(skb, sizeof(smp->rrnd)); |
e7e62c85 | 1460 | |
191dc7fe JH |
1461 | if (!test_bit(SMP_FLAG_SC, &smp->flags)) |
1462 | return smp_random(smp); | |
1463 | ||
1464 | if (hcon->out) { | |
1465 | u8 cfm[16]; | |
1466 | ||
1467 | err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, | |
1468 | smp->rrnd, 0, cfm); | |
1469 | if (err) | |
1470 | return SMP_UNSPECIFIED; | |
1471 | ||
1472 | if (memcmp(smp->pcnf, cfm, 16)) | |
1473 | return SMP_CONFIRM_FAILED; | |
1474 | ||
1475 | pkax = smp->local_pk; | |
1476 | pkbx = smp->remote_pk; | |
1477 | na = smp->prnd; | |
1478 | nb = smp->rrnd; | |
1479 | } else { | |
1480 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), | |
1481 | smp->prnd); | |
1482 | SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); | |
1483 | ||
1484 | pkax = smp->remote_pk; | |
1485 | pkbx = smp->local_pk; | |
1486 | na = smp->rrnd; | |
1487 | nb = smp->prnd; | |
1488 | } | |
1489 | ||
760b018b JH |
1490 | /* Generate MacKey and LTK */ |
1491 | err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); | |
1492 | if (err) | |
1493 | return SMP_UNSPECIFIED; | |
1494 | ||
191dc7fe JH |
1495 | err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); |
1496 | if (err) | |
1497 | return SMP_UNSPECIFIED; | |
1498 | ||
1499 | err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, | |
1500 | hcon->type, hcon->dst_type, | |
1501 | passkey, 0); | |
1502 | if (err) | |
1503 | return SMP_UNSPECIFIED; | |
1504 | ||
1505 | return 0; | |
88ba43b6 AB |
1506 | } |
1507 | ||
f81cd823 | 1508 | static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) |
988c5997 | 1509 | { |
c9839a11 | 1510 | struct smp_ltk *key; |
988c5997 VCG |
1511 | struct hci_conn *hcon = conn->hcon; |
1512 | ||
f3a73d97 | 1513 | key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); |
988c5997 | 1514 | if (!key) |
f81cd823 | 1515 | return false; |
988c5997 | 1516 | |
a6f7833c | 1517 | if (smp_ltk_sec_level(key) < sec_level) |
f81cd823 | 1518 | return false; |
4dab7864 | 1519 | |
51a8efd7 | 1520 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) |
f81cd823 | 1521 | return true; |
988c5997 | 1522 | |
c9839a11 VCG |
1523 | hci_le_start_enc(hcon, key->ediv, key->rand, key->val); |
1524 | hcon->enc_key_size = key->enc_size; | |
988c5997 | 1525 | |
fe59a05f JH |
1526 | /* We never store STKs for master role, so clear this flag */ |
1527 | clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); | |
1528 | ||
f81cd823 | 1529 | return true; |
988c5997 | 1530 | } |
f1560463 | 1531 | |
35dc6f83 JH |
1532 | bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, |
1533 | enum smp_key_pref key_pref) | |
854f4727 JH |
1534 | { |
1535 | if (sec_level == BT_SECURITY_LOW) | |
1536 | return true; | |
1537 | ||
35dc6f83 JH |
1538 | /* If we're encrypted with an STK but the caller prefers using |
1539 | * LTK claim insufficient security. This way we allow the | |
1540 | * connection to be re-encrypted with an LTK, even if the LTK | |
1541 | * provides the same level of security. Only exception is if we | |
1542 | * don't have an LTK (e.g. because of key distribution bits). | |
9ab65d60 | 1543 | */ |
35dc6f83 JH |
1544 | if (key_pref == SMP_USE_LTK && |
1545 | test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && | |
f3a73d97 | 1546 | hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) |
9ab65d60 JH |
1547 | return false; |
1548 | ||
854f4727 JH |
1549 | if (hcon->sec_level >= sec_level) |
1550 | return true; | |
1551 | ||
1552 | return false; | |
1553 | } | |
1554 | ||
da85e5e5 | 1555 | static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 AB |
1556 | { |
1557 | struct smp_cmd_security_req *rp = (void *) skb->data; | |
1558 | struct smp_cmd_pairing cp; | |
f1cb9af5 | 1559 | struct hci_conn *hcon = conn->hcon; |
0edb14de | 1560 | struct hci_dev *hdev = hcon->hdev; |
8aab4757 | 1561 | struct smp_chan *smp; |
c05b9339 | 1562 | u8 sec_level, auth; |
88ba43b6 AB |
1563 | |
1564 | BT_DBG("conn %p", conn); | |
1565 | ||
c46b98be | 1566 | if (skb->len < sizeof(*rp)) |
38e4a915 | 1567 | return SMP_INVALID_PARAMS; |
c46b98be | 1568 | |
40bef302 | 1569 | if (hcon->role != HCI_ROLE_MASTER) |
86ca9eac JH |
1570 | return SMP_CMD_NOTSUPP; |
1571 | ||
0edb14de | 1572 | auth = rp->auth_req & AUTH_REQ_MASK(hdev); |
c05b9339 | 1573 | |
5be5e275 | 1574 | if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) |
1afc2a1a JH |
1575 | sec_level = BT_SECURITY_MEDIUM; |
1576 | else | |
1577 | sec_level = authreq_to_seclevel(auth); | |
1578 | ||
35dc6f83 | 1579 | if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) |
854f4727 JH |
1580 | return 0; |
1581 | ||
c7262e71 JH |
1582 | if (sec_level > hcon->pending_sec_level) |
1583 | hcon->pending_sec_level = sec_level; | |
feb45eb5 | 1584 | |
4dab7864 | 1585 | if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) |
988c5997 VCG |
1586 | return 0; |
1587 | ||
8aab4757 | 1588 | smp = smp_chan_create(conn); |
c29d2444 JH |
1589 | if (!smp) |
1590 | return SMP_UNSPECIFIED; | |
d26a2345 | 1591 | |
b6ae8457 | 1592 | if (!test_bit(HCI_BONDABLE, &hcon->hdev->dev_flags) && |
c05b9339 | 1593 | (auth & SMP_AUTH_BONDING)) |
616d55be JH |
1594 | return SMP_PAIRING_NOTSUPP; |
1595 | ||
88ba43b6 | 1596 | skb_pull(skb, sizeof(*rp)); |
88ba43b6 | 1597 | |
da85e5e5 | 1598 | memset(&cp, 0, sizeof(cp)); |
c05b9339 | 1599 | build_pairing_cmd(conn, &cp, NULL, auth); |
88ba43b6 | 1600 | |
1c1def09 VCG |
1601 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
1602 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 1603 | |
88ba43b6 | 1604 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
b28b4943 | 1605 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); |
f1cb9af5 | 1606 | |
da85e5e5 | 1607 | return 0; |
88ba43b6 AB |
1608 | } |
1609 | ||
cc110922 | 1610 | int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) |
eb492e01 | 1611 | { |
cc110922 | 1612 | struct l2cap_conn *conn = hcon->l2cap_data; |
c68b7f12 | 1613 | struct l2cap_chan *chan; |
0a66cf20 | 1614 | struct smp_chan *smp; |
2b64d153 | 1615 | __u8 authreq; |
fc75cc86 | 1616 | int ret; |
eb492e01 | 1617 | |
3a0259bb VCG |
1618 | BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); |
1619 | ||
0a66cf20 JH |
1620 | /* This may be NULL if there's an unexpected disconnection */ |
1621 | if (!conn) | |
1622 | return 1; | |
1623 | ||
c68b7f12 JH |
1624 | chan = conn->smp; |
1625 | ||
757aee0f | 1626 | if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) |
2e65c9d2 AG |
1627 | return 1; |
1628 | ||
35dc6f83 | 1629 | if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) |
eb492e01 | 1630 | return 1; |
f1cb9af5 | 1631 | |
c7262e71 JH |
1632 | if (sec_level > hcon->pending_sec_level) |
1633 | hcon->pending_sec_level = sec_level; | |
1634 | ||
40bef302 | 1635 | if (hcon->role == HCI_ROLE_MASTER) |
c7262e71 JH |
1636 | if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) |
1637 | return 0; | |
d26a2345 | 1638 | |
fc75cc86 JH |
1639 | l2cap_chan_lock(chan); |
1640 | ||
1641 | /* If SMP is already in progress ignore this request */ | |
1642 | if (chan->data) { | |
1643 | ret = 0; | |
1644 | goto unlock; | |
1645 | } | |
d26a2345 | 1646 | |
8aab4757 | 1647 | smp = smp_chan_create(conn); |
fc75cc86 JH |
1648 | if (!smp) { |
1649 | ret = 1; | |
1650 | goto unlock; | |
1651 | } | |
2b64d153 BG |
1652 | |
1653 | authreq = seclevel_to_authreq(sec_level); | |
d26a2345 | 1654 | |
d2eb9e10 JH |
1655 | if (test_bit(HCI_SC_ENABLED, &hcon->hdev->dev_flags)) |
1656 | authreq |= SMP_AUTH_SC; | |
1657 | ||
79897d20 JH |
1658 | /* Require MITM if IO Capability allows or the security level |
1659 | * requires it. | |
2e233644 | 1660 | */ |
79897d20 | 1661 | if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || |
c7262e71 | 1662 | hcon->pending_sec_level > BT_SECURITY_MEDIUM) |
2e233644 JH |
1663 | authreq |= SMP_AUTH_MITM; |
1664 | ||
40bef302 | 1665 | if (hcon->role == HCI_ROLE_MASTER) { |
d26a2345 | 1666 | struct smp_cmd_pairing cp; |
f01ead31 | 1667 | |
2b64d153 | 1668 | build_pairing_cmd(conn, &cp, NULL, authreq); |
1c1def09 VCG |
1669 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
1670 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 1671 | |
eb492e01 | 1672 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
b28b4943 | 1673 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); |
eb492e01 AB |
1674 | } else { |
1675 | struct smp_cmd_security_req cp; | |
2b64d153 | 1676 | cp.auth_req = authreq; |
eb492e01 | 1677 | smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); |
b28b4943 | 1678 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); |
eb492e01 AB |
1679 | } |
1680 | ||
4a74d658 | 1681 | set_bit(SMP_FLAG_INITIATOR, &smp->flags); |
fc75cc86 | 1682 | ret = 0; |
edca792c | 1683 | |
fc75cc86 JH |
1684 | unlock: |
1685 | l2cap_chan_unlock(chan); | |
1686 | return ret; | |
eb492e01 AB |
1687 | } |
1688 | ||
7034b911 VCG |
1689 | static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1690 | { | |
16b90839 | 1691 | struct smp_cmd_encrypt_info *rp = (void *) skb->data; |
5d88cc73 JH |
1692 | struct l2cap_chan *chan = conn->smp; |
1693 | struct smp_chan *smp = chan->data; | |
16b90839 | 1694 | |
c46b98be JH |
1695 | BT_DBG("conn %p", conn); |
1696 | ||
1697 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1698 | return SMP_INVALID_PARAMS; |
c46b98be | 1699 | |
b28b4943 | 1700 | SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); |
6131ddc8 | 1701 | |
16b90839 VCG |
1702 | skb_pull(skb, sizeof(*rp)); |
1703 | ||
1c1def09 | 1704 | memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); |
16b90839 | 1705 | |
7034b911 VCG |
1706 | return 0; |
1707 | } | |
1708 | ||
1709 | static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) | |
1710 | { | |
16b90839 | 1711 | struct smp_cmd_master_ident *rp = (void *) skb->data; |
5d88cc73 JH |
1712 | struct l2cap_chan *chan = conn->smp; |
1713 | struct smp_chan *smp = chan->data; | |
c9839a11 VCG |
1714 | struct hci_dev *hdev = conn->hcon->hdev; |
1715 | struct hci_conn *hcon = conn->hcon; | |
23d0e128 | 1716 | struct smp_ltk *ltk; |
c9839a11 | 1717 | u8 authenticated; |
16b90839 | 1718 | |
c46b98be JH |
1719 | BT_DBG("conn %p", conn); |
1720 | ||
1721 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1722 | return SMP_INVALID_PARAMS; |
c46b98be | 1723 | |
9747a9f3 JH |
1724 | /* Mark the information as received */ |
1725 | smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; | |
1726 | ||
b28b4943 JH |
1727 | if (smp->remote_key_dist & SMP_DIST_ID_KEY) |
1728 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); | |
196332f5 JH |
1729 | else if (smp->remote_key_dist & SMP_DIST_SIGN) |
1730 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
b28b4943 | 1731 | |
16b90839 | 1732 | skb_pull(skb, sizeof(*rp)); |
7034b911 | 1733 | |
ce39fb4e | 1734 | authenticated = (hcon->sec_level == BT_SECURITY_HIGH); |
2ceba539 | 1735 | ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, |
23d0e128 JH |
1736 | authenticated, smp->tk, smp->enc_key_size, |
1737 | rp->ediv, rp->rand); | |
1738 | smp->ltk = ltk; | |
c6e81e9a | 1739 | if (!(smp->remote_key_dist & KEY_DIST_MASK)) |
d6268e86 | 1740 | smp_distribute_keys(smp); |
7034b911 VCG |
1741 | |
1742 | return 0; | |
1743 | } | |
1744 | ||
fd349c02 JH |
1745 | static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1746 | { | |
1747 | struct smp_cmd_ident_info *info = (void *) skb->data; | |
5d88cc73 JH |
1748 | struct l2cap_chan *chan = conn->smp; |
1749 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
1750 | |
1751 | BT_DBG(""); | |
1752 | ||
1753 | if (skb->len < sizeof(*info)) | |
38e4a915 | 1754 | return SMP_INVALID_PARAMS; |
fd349c02 | 1755 | |
b28b4943 | 1756 | SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); |
6131ddc8 | 1757 | |
fd349c02 JH |
1758 | skb_pull(skb, sizeof(*info)); |
1759 | ||
1760 | memcpy(smp->irk, info->irk, 16); | |
1761 | ||
1762 | return 0; | |
1763 | } | |
1764 | ||
1765 | static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, | |
1766 | struct sk_buff *skb) | |
1767 | { | |
1768 | struct smp_cmd_ident_addr_info *info = (void *) skb->data; | |
5d88cc73 JH |
1769 | struct l2cap_chan *chan = conn->smp; |
1770 | struct smp_chan *smp = chan->data; | |
fd349c02 JH |
1771 | struct hci_conn *hcon = conn->hcon; |
1772 | bdaddr_t rpa; | |
1773 | ||
1774 | BT_DBG(""); | |
1775 | ||
1776 | if (skb->len < sizeof(*info)) | |
38e4a915 | 1777 | return SMP_INVALID_PARAMS; |
fd349c02 | 1778 | |
9747a9f3 JH |
1779 | /* Mark the information as received */ |
1780 | smp->remote_key_dist &= ~SMP_DIST_ID_KEY; | |
1781 | ||
b28b4943 JH |
1782 | if (smp->remote_key_dist & SMP_DIST_SIGN) |
1783 | SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); | |
1784 | ||
fd349c02 JH |
1785 | skb_pull(skb, sizeof(*info)); |
1786 | ||
a9a58f86 JH |
1787 | /* Strictly speaking the Core Specification (4.1) allows sending |
1788 | * an empty address which would force us to rely on just the IRK | |
1789 | * as "identity information". However, since such | |
1790 | * implementations are not known of and in order to not over | |
1791 | * complicate our implementation, simply pretend that we never | |
1792 | * received an IRK for such a device. | |
1793 | */ | |
1794 | if (!bacmp(&info->bdaddr, BDADDR_ANY)) { | |
1795 | BT_ERR("Ignoring IRK with no identity address"); | |
31dd624e | 1796 | goto distribute; |
a9a58f86 JH |
1797 | } |
1798 | ||
fd349c02 JH |
1799 | bacpy(&smp->id_addr, &info->bdaddr); |
1800 | smp->id_addr_type = info->addr_type; | |
1801 | ||
1802 | if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) | |
1803 | bacpy(&rpa, &hcon->dst); | |
1804 | else | |
1805 | bacpy(&rpa, BDADDR_ANY); | |
1806 | ||
23d0e128 JH |
1807 | smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, |
1808 | smp->id_addr_type, smp->irk, &rpa); | |
fd349c02 | 1809 | |
31dd624e | 1810 | distribute: |
c6e81e9a JH |
1811 | if (!(smp->remote_key_dist & KEY_DIST_MASK)) |
1812 | smp_distribute_keys(smp); | |
fd349c02 JH |
1813 | |
1814 | return 0; | |
1815 | } | |
1816 | ||
7ee4ea36 MH |
1817 | static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) |
1818 | { | |
1819 | struct smp_cmd_sign_info *rp = (void *) skb->data; | |
5d88cc73 JH |
1820 | struct l2cap_chan *chan = conn->smp; |
1821 | struct smp_chan *smp = chan->data; | |
7ee4ea36 MH |
1822 | struct smp_csrk *csrk; |
1823 | ||
1824 | BT_DBG("conn %p", conn); | |
1825 | ||
1826 | if (skb->len < sizeof(*rp)) | |
38e4a915 | 1827 | return SMP_INVALID_PARAMS; |
7ee4ea36 | 1828 | |
7ee4ea36 MH |
1829 | /* Mark the information as received */ |
1830 | smp->remote_key_dist &= ~SMP_DIST_SIGN; | |
1831 | ||
1832 | skb_pull(skb, sizeof(*rp)); | |
1833 | ||
7ee4ea36 MH |
1834 | csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); |
1835 | if (csrk) { | |
1836 | csrk->master = 0x01; | |
1837 | memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); | |
1838 | } | |
1839 | smp->csrk = csrk; | |
d6268e86 | 1840 | smp_distribute_keys(smp); |
7ee4ea36 MH |
1841 | |
1842 | return 0; | |
1843 | } | |
1844 | ||
d8f8edbe JH |
1845 | static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) |
1846 | { | |
1847 | struct smp_cmd_public_key *key = (void *) skb->data; | |
1848 | struct hci_conn *hcon = conn->hcon; | |
1849 | struct l2cap_chan *chan = conn->smp; | |
1850 | struct smp_chan *smp = chan->data; | |
cbbbe3e2 | 1851 | struct smp_cmd_pairing_confirm cfm; |
d8f8edbe JH |
1852 | int err; |
1853 | ||
1854 | BT_DBG("conn %p", conn); | |
1855 | ||
1856 | if (skb->len < sizeof(*key)) | |
1857 | return SMP_INVALID_PARAMS; | |
1858 | ||
1859 | memcpy(smp->remote_pk, key, 64); | |
1860 | ||
1861 | /* Non-initiating device sends its public key after receiving | |
1862 | * the key from the initiating device. | |
1863 | */ | |
1864 | if (!hcon->out) { | |
1865 | err = sc_send_public_key(smp); | |
1866 | if (err) | |
1867 | return err; | |
1868 | } | |
1869 | ||
1870 | BT_DBG("Remote Public Key X: %32phN", smp->remote_pk); | |
1871 | BT_DBG("Remote Public Key Y: %32phN", &smp->remote_pk[32]); | |
1872 | ||
1873 | if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey)) | |
1874 | return SMP_UNSPECIFIED; | |
1875 | ||
1876 | BT_DBG("DHKey %32phN", smp->dhkey); | |
1877 | ||
1878 | set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); | |
1879 | ||
cbbbe3e2 JH |
1880 | /* The Initiating device waits for the non-initiating device to |
1881 | * send the confirm value. | |
1882 | */ | |
1883 | if (conn->hcon->out) | |
1884 | return 0; | |
1885 | ||
1886 | err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, | |
1887 | 0, cfm.confirm_val); | |
1888 | if (err) | |
1889 | return SMP_UNSPECIFIED; | |
1890 | ||
1891 | smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); | |
1892 | SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); | |
1893 | ||
d8f8edbe JH |
1894 | return 0; |
1895 | } | |
1896 | ||
6433a9a2 JH |
1897 | static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) |
1898 | { | |
1899 | struct smp_cmd_dhkey_check *check = (void *) skb->data; | |
1900 | struct l2cap_chan *chan = conn->smp; | |
1901 | struct hci_conn *hcon = conn->hcon; | |
1902 | struct smp_chan *smp = chan->data; | |
1903 | u8 a[7], b[7], *local_addr, *remote_addr; | |
1904 | u8 io_cap[3], r[16], e[16]; | |
1905 | int err; | |
1906 | ||
1907 | BT_DBG("conn %p", conn); | |
1908 | ||
1909 | if (skb->len < sizeof(*check)) | |
1910 | return SMP_INVALID_PARAMS; | |
1911 | ||
1912 | memcpy(a, &hcon->init_addr, 6); | |
1913 | memcpy(b, &hcon->resp_addr, 6); | |
1914 | a[6] = hcon->init_addr_type; | |
1915 | b[6] = hcon->resp_addr_type; | |
1916 | ||
1917 | if (hcon->out) { | |
1918 | local_addr = a; | |
1919 | remote_addr = b; | |
1920 | memcpy(io_cap, &smp->prsp[1], 3); | |
1921 | } else { | |
1922 | local_addr = b; | |
1923 | remote_addr = a; | |
1924 | memcpy(io_cap, &smp->preq[1], 3); | |
1925 | } | |
1926 | ||
1927 | memset(r, 0, sizeof(r)); | |
1928 | ||
1929 | err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, | |
1930 | io_cap, remote_addr, local_addr, e); | |
1931 | if (err) | |
1932 | return SMP_UNSPECIFIED; | |
1933 | ||
1934 | if (memcmp(check->e, e, 16)) | |
1935 | return SMP_DHKEY_CHECK_FAILED; | |
1936 | ||
1937 | smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, | |
1938 | SMP_LTK_P256, 0, smp->tk, smp->enc_key_size, | |
1939 | 0, 0); | |
1940 | ||
1941 | if (hcon->out) { | |
1942 | hci_le_start_enc(hcon, 0, 0, smp->tk); | |
1943 | hcon->enc_key_size = smp->enc_key_size; | |
1944 | } | |
1945 | ||
1946 | return 0; | |
1947 | } | |
1948 | ||
4befb867 | 1949 | static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) |
eb492e01 | 1950 | { |
5d88cc73 | 1951 | struct l2cap_conn *conn = chan->conn; |
7b9899db | 1952 | struct hci_conn *hcon = conn->hcon; |
b28b4943 | 1953 | struct smp_chan *smp; |
92381f5c | 1954 | __u8 code, reason; |
eb492e01 AB |
1955 | int err = 0; |
1956 | ||
7b9899db MH |
1957 | if (hcon->type != LE_LINK) { |
1958 | kfree_skb(skb); | |
3432711f | 1959 | return 0; |
7b9899db MH |
1960 | } |
1961 | ||
8ae9b984 | 1962 | if (skb->len < 1) |
92381f5c | 1963 | return -EILSEQ; |
92381f5c | 1964 | |
06ae3314 | 1965 | if (!test_bit(HCI_LE_ENABLED, &hcon->hdev->dev_flags)) { |
2e65c9d2 AG |
1966 | reason = SMP_PAIRING_NOTSUPP; |
1967 | goto done; | |
1968 | } | |
1969 | ||
92381f5c | 1970 | code = skb->data[0]; |
eb492e01 AB |
1971 | skb_pull(skb, sizeof(code)); |
1972 | ||
b28b4943 JH |
1973 | smp = chan->data; |
1974 | ||
1975 | if (code > SMP_CMD_MAX) | |
1976 | goto drop; | |
1977 | ||
24bd0bd9 | 1978 | if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) |
b28b4943 JH |
1979 | goto drop; |
1980 | ||
1981 | /* If we don't have a context the only allowed commands are | |
1982 | * pairing request and security request. | |
8cf9fa12 | 1983 | */ |
b28b4943 JH |
1984 | if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) |
1985 | goto drop; | |
8cf9fa12 | 1986 | |
eb492e01 AB |
1987 | switch (code) { |
1988 | case SMP_CMD_PAIRING_REQ: | |
da85e5e5 | 1989 | reason = smp_cmd_pairing_req(conn, skb); |
eb492e01 AB |
1990 | break; |
1991 | ||
1992 | case SMP_CMD_PAIRING_FAIL: | |
84794e11 | 1993 | smp_failure(conn, 0); |
da85e5e5 | 1994 | err = -EPERM; |
eb492e01 AB |
1995 | break; |
1996 | ||
1997 | case SMP_CMD_PAIRING_RSP: | |
da85e5e5 | 1998 | reason = smp_cmd_pairing_rsp(conn, skb); |
88ba43b6 AB |
1999 | break; |
2000 | ||
2001 | case SMP_CMD_SECURITY_REQ: | |
da85e5e5 | 2002 | reason = smp_cmd_security_req(conn, skb); |
88ba43b6 AB |
2003 | break; |
2004 | ||
eb492e01 | 2005 | case SMP_CMD_PAIRING_CONFIRM: |
da85e5e5 | 2006 | reason = smp_cmd_pairing_confirm(conn, skb); |
88ba43b6 AB |
2007 | break; |
2008 | ||
eb492e01 | 2009 | case SMP_CMD_PAIRING_RANDOM: |
da85e5e5 | 2010 | reason = smp_cmd_pairing_random(conn, skb); |
88ba43b6 AB |
2011 | break; |
2012 | ||
eb492e01 | 2013 | case SMP_CMD_ENCRYPT_INFO: |
7034b911 VCG |
2014 | reason = smp_cmd_encrypt_info(conn, skb); |
2015 | break; | |
2016 | ||
eb492e01 | 2017 | case SMP_CMD_MASTER_IDENT: |
7034b911 VCG |
2018 | reason = smp_cmd_master_ident(conn, skb); |
2019 | break; | |
2020 | ||
eb492e01 | 2021 | case SMP_CMD_IDENT_INFO: |
fd349c02 JH |
2022 | reason = smp_cmd_ident_info(conn, skb); |
2023 | break; | |
2024 | ||
eb492e01 | 2025 | case SMP_CMD_IDENT_ADDR_INFO: |
fd349c02 JH |
2026 | reason = smp_cmd_ident_addr_info(conn, skb); |
2027 | break; | |
2028 | ||
eb492e01 | 2029 | case SMP_CMD_SIGN_INFO: |
7ee4ea36 | 2030 | reason = smp_cmd_sign_info(conn, skb); |
7034b911 VCG |
2031 | break; |
2032 | ||
d8f8edbe JH |
2033 | case SMP_CMD_PUBLIC_KEY: |
2034 | reason = smp_cmd_public_key(conn, skb); | |
2035 | break; | |
2036 | ||
6433a9a2 JH |
2037 | case SMP_CMD_DHKEY_CHECK: |
2038 | reason = smp_cmd_dhkey_check(conn, skb); | |
2039 | break; | |
2040 | ||
eb492e01 AB |
2041 | default: |
2042 | BT_DBG("Unknown command code 0x%2.2x", code); | |
eb492e01 | 2043 | reason = SMP_CMD_NOTSUPP; |
3a0259bb | 2044 | goto done; |
eb492e01 AB |
2045 | } |
2046 | ||
3a0259bb | 2047 | done: |
9b7b18ef JH |
2048 | if (!err) { |
2049 | if (reason) | |
2050 | smp_failure(conn, reason); | |
8ae9b984 | 2051 | kfree_skb(skb); |
9b7b18ef JH |
2052 | } |
2053 | ||
eb492e01 | 2054 | return err; |
b28b4943 JH |
2055 | |
2056 | drop: | |
2057 | BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name, | |
2058 | code, &hcon->dst); | |
2059 | kfree_skb(skb); | |
2060 | return 0; | |
eb492e01 | 2061 | } |
7034b911 | 2062 | |
70db83c4 JH |
2063 | static void smp_teardown_cb(struct l2cap_chan *chan, int err) |
2064 | { | |
2065 | struct l2cap_conn *conn = chan->conn; | |
2066 | ||
2067 | BT_DBG("chan %p", chan); | |
2068 | ||
fc75cc86 | 2069 | if (chan->data) |
5d88cc73 | 2070 | smp_chan_destroy(conn); |
5d88cc73 | 2071 | |
70db83c4 JH |
2072 | conn->smp = NULL; |
2073 | l2cap_chan_put(chan); | |
2074 | } | |
2075 | ||
44f1a7ab JH |
2076 | static void smp_resume_cb(struct l2cap_chan *chan) |
2077 | { | |
b68fda68 | 2078 | struct smp_chan *smp = chan->data; |
44f1a7ab JH |
2079 | struct l2cap_conn *conn = chan->conn; |
2080 | struct hci_conn *hcon = conn->hcon; | |
2081 | ||
2082 | BT_DBG("chan %p", chan); | |
2083 | ||
86d1407c JH |
2084 | if (!smp) |
2085 | return; | |
b68fda68 | 2086 | |
84bc0db5 JH |
2087 | if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) |
2088 | return; | |
2089 | ||
86d1407c JH |
2090 | cancel_delayed_work(&smp->security_timer); |
2091 | ||
d6268e86 | 2092 | smp_distribute_keys(smp); |
44f1a7ab JH |
2093 | } |
2094 | ||
70db83c4 JH |
2095 | static void smp_ready_cb(struct l2cap_chan *chan) |
2096 | { | |
2097 | struct l2cap_conn *conn = chan->conn; | |
2098 | ||
2099 | BT_DBG("chan %p", chan); | |
2100 | ||
2101 | conn->smp = chan; | |
2102 | l2cap_chan_hold(chan); | |
2103 | } | |
2104 | ||
4befb867 JH |
2105 | static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) |
2106 | { | |
2107 | int err; | |
2108 | ||
2109 | BT_DBG("chan %p", chan); | |
2110 | ||
2111 | err = smp_sig_channel(chan, skb); | |
2112 | if (err) { | |
b68fda68 | 2113 | struct smp_chan *smp = chan->data; |
4befb867 | 2114 | |
b68fda68 JH |
2115 | if (smp) |
2116 | cancel_delayed_work_sync(&smp->security_timer); | |
4befb867 | 2117 | |
1e91c29e | 2118 | hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); |
4befb867 JH |
2119 | } |
2120 | ||
2121 | return err; | |
2122 | } | |
2123 | ||
70db83c4 JH |
2124 | static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, |
2125 | unsigned long hdr_len, | |
2126 | unsigned long len, int nb) | |
2127 | { | |
2128 | struct sk_buff *skb; | |
2129 | ||
2130 | skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); | |
2131 | if (!skb) | |
2132 | return ERR_PTR(-ENOMEM); | |
2133 | ||
2134 | skb->priority = HCI_PRIO_MAX; | |
2135 | bt_cb(skb)->chan = chan; | |
2136 | ||
2137 | return skb; | |
2138 | } | |
2139 | ||
2140 | static const struct l2cap_ops smp_chan_ops = { | |
2141 | .name = "Security Manager", | |
2142 | .ready = smp_ready_cb, | |
5d88cc73 | 2143 | .recv = smp_recv_cb, |
70db83c4 JH |
2144 | .alloc_skb = smp_alloc_skb_cb, |
2145 | .teardown = smp_teardown_cb, | |
44f1a7ab | 2146 | .resume = smp_resume_cb, |
70db83c4 JH |
2147 | |
2148 | .new_connection = l2cap_chan_no_new_connection, | |
70db83c4 JH |
2149 | .state_change = l2cap_chan_no_state_change, |
2150 | .close = l2cap_chan_no_close, | |
2151 | .defer = l2cap_chan_no_defer, | |
2152 | .suspend = l2cap_chan_no_suspend, | |
70db83c4 JH |
2153 | .set_shutdown = l2cap_chan_no_set_shutdown, |
2154 | .get_sndtimeo = l2cap_chan_no_get_sndtimeo, | |
2155 | .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec, | |
2156 | }; | |
2157 | ||
2158 | static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) | |
2159 | { | |
2160 | struct l2cap_chan *chan; | |
2161 | ||
2162 | BT_DBG("pchan %p", pchan); | |
2163 | ||
2164 | chan = l2cap_chan_create(); | |
2165 | if (!chan) | |
2166 | return NULL; | |
2167 | ||
2168 | chan->chan_type = pchan->chan_type; | |
2169 | chan->ops = &smp_chan_ops; | |
2170 | chan->scid = pchan->scid; | |
2171 | chan->dcid = chan->scid; | |
2172 | chan->imtu = pchan->imtu; | |
2173 | chan->omtu = pchan->omtu; | |
2174 | chan->mode = pchan->mode; | |
2175 | ||
abe84903 JH |
2176 | /* Other L2CAP channels may request SMP routines in order to |
2177 | * change the security level. This means that the SMP channel | |
2178 | * lock must be considered in its own category to avoid lockdep | |
2179 | * warnings. | |
2180 | */ | |
2181 | atomic_set(&chan->nesting, L2CAP_NESTING_SMP); | |
2182 | ||
70db83c4 JH |
2183 | BT_DBG("created chan %p", chan); |
2184 | ||
2185 | return chan; | |
2186 | } | |
2187 | ||
2188 | static const struct l2cap_ops smp_root_chan_ops = { | |
2189 | .name = "Security Manager Root", | |
2190 | .new_connection = smp_new_conn_cb, | |
2191 | ||
2192 | /* None of these are implemented for the root channel */ | |
2193 | .close = l2cap_chan_no_close, | |
2194 | .alloc_skb = l2cap_chan_no_alloc_skb, | |
2195 | .recv = l2cap_chan_no_recv, | |
2196 | .state_change = l2cap_chan_no_state_change, | |
2197 | .teardown = l2cap_chan_no_teardown, | |
2198 | .ready = l2cap_chan_no_ready, | |
2199 | .defer = l2cap_chan_no_defer, | |
2200 | .suspend = l2cap_chan_no_suspend, | |
2201 | .resume = l2cap_chan_no_resume, | |
2202 | .set_shutdown = l2cap_chan_no_set_shutdown, | |
2203 | .get_sndtimeo = l2cap_chan_no_get_sndtimeo, | |
2204 | .memcpy_fromiovec = l2cap_chan_no_memcpy_fromiovec, | |
2205 | }; | |
2206 | ||
711eafe3 JH |
2207 | int smp_register(struct hci_dev *hdev) |
2208 | { | |
70db83c4 | 2209 | struct l2cap_chan *chan; |
defce9e8 | 2210 | struct crypto_blkcipher *tfm_aes; |
70db83c4 | 2211 | |
711eafe3 JH |
2212 | BT_DBG("%s", hdev->name); |
2213 | ||
adae20cb | 2214 | tfm_aes = crypto_alloc_blkcipher("ecb(aes)", 0, 0); |
defce9e8 JH |
2215 | if (IS_ERR(tfm_aes)) { |
2216 | int err = PTR_ERR(tfm_aes); | |
711eafe3 | 2217 | BT_ERR("Unable to create crypto context"); |
711eafe3 JH |
2218 | return err; |
2219 | } | |
2220 | ||
70db83c4 JH |
2221 | chan = l2cap_chan_create(); |
2222 | if (!chan) { | |
defce9e8 | 2223 | crypto_free_blkcipher(tfm_aes); |
70db83c4 JH |
2224 | return -ENOMEM; |
2225 | } | |
2226 | ||
defce9e8 JH |
2227 | chan->data = tfm_aes; |
2228 | ||
5d88cc73 | 2229 | l2cap_add_scid(chan, L2CAP_CID_SMP); |
70db83c4 JH |
2230 | |
2231 | l2cap_chan_set_defaults(chan); | |
2232 | ||
2233 | bacpy(&chan->src, &hdev->bdaddr); | |
2234 | chan->src_type = BDADDR_LE_PUBLIC; | |
2235 | chan->state = BT_LISTEN; | |
2236 | chan->mode = L2CAP_MODE_BASIC; | |
2237 | chan->imtu = L2CAP_DEFAULT_MTU; | |
2238 | chan->ops = &smp_root_chan_ops; | |
2239 | ||
abe84903 JH |
2240 | /* Set correct nesting level for a parent/listening channel */ |
2241 | atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); | |
2242 | ||
70db83c4 JH |
2243 | hdev->smp_data = chan; |
2244 | ||
711eafe3 JH |
2245 | return 0; |
2246 | } | |
2247 | ||
2248 | void smp_unregister(struct hci_dev *hdev) | |
2249 | { | |
70db83c4 | 2250 | struct l2cap_chan *chan = hdev->smp_data; |
defce9e8 | 2251 | struct crypto_blkcipher *tfm_aes; |
70db83c4 JH |
2252 | |
2253 | if (!chan) | |
2254 | return; | |
2255 | ||
2256 | BT_DBG("%s chan %p", hdev->name, chan); | |
711eafe3 | 2257 | |
defce9e8 JH |
2258 | tfm_aes = chan->data; |
2259 | if (tfm_aes) { | |
2260 | chan->data = NULL; | |
2261 | crypto_free_blkcipher(tfm_aes); | |
711eafe3 | 2262 | } |
70db83c4 JH |
2263 | |
2264 | hdev->smp_data = NULL; | |
2265 | l2cap_chan_put(chan); | |
711eafe3 | 2266 | } |