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Commit | Line | Data |
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eb492e01 AB |
1 | /* |
2 | BlueZ - Bluetooth protocol stack for Linux | |
3 | Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License version 2 as | |
7 | published by the Free Software Foundation; | |
8 | ||
9 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS | |
10 | OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
11 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. | |
12 | IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY | |
13 | CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES | |
14 | WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | |
15 | ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | |
16 | OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | |
17 | ||
18 | ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, | |
19 | COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS | |
20 | SOFTWARE IS DISCLAIMED. | |
21 | */ | |
22 | ||
23 | #include <net/bluetooth/bluetooth.h> | |
24 | #include <net/bluetooth/hci_core.h> | |
25 | #include <net/bluetooth/l2cap.h> | |
26 | #include <net/bluetooth/smp.h> | |
d22ef0bc | 27 | #include <linux/crypto.h> |
f70490e6 | 28 | #include <linux/scatterlist.h> |
d22ef0bc AB |
29 | #include <crypto/b128ops.h> |
30 | ||
5d3de7df VCG |
31 | #define SMP_TIMEOUT 30000 /* 30 seconds */ |
32 | ||
d22ef0bc AB |
33 | static inline void swap128(u8 src[16], u8 dst[16]) |
34 | { | |
35 | int i; | |
36 | for (i = 0; i < 16; i++) | |
37 | dst[15 - i] = src[i]; | |
38 | } | |
39 | ||
40 | static inline void swap56(u8 src[7], u8 dst[7]) | |
41 | { | |
42 | int i; | |
43 | for (i = 0; i < 7; i++) | |
44 | dst[6 - i] = src[i]; | |
45 | } | |
46 | ||
47 | static int smp_e(struct crypto_blkcipher *tfm, const u8 *k, u8 *r) | |
48 | { | |
49 | struct blkcipher_desc desc; | |
50 | struct scatterlist sg; | |
51 | int err, iv_len; | |
52 | unsigned char iv[128]; | |
53 | ||
54 | if (tfm == NULL) { | |
55 | BT_ERR("tfm %p", tfm); | |
56 | return -EINVAL; | |
57 | } | |
58 | ||
59 | desc.tfm = tfm; | |
60 | desc.flags = 0; | |
61 | ||
62 | err = crypto_blkcipher_setkey(tfm, k, 16); | |
63 | if (err) { | |
64 | BT_ERR("cipher setkey failed: %d", err); | |
65 | return err; | |
66 | } | |
67 | ||
68 | sg_init_one(&sg, r, 16); | |
69 | ||
70 | iv_len = crypto_blkcipher_ivsize(tfm); | |
71 | if (iv_len) { | |
72 | memset(&iv, 0xff, iv_len); | |
73 | crypto_blkcipher_set_iv(tfm, iv, iv_len); | |
74 | } | |
75 | ||
76 | err = crypto_blkcipher_encrypt(&desc, &sg, &sg, 16); | |
77 | if (err) | |
78 | BT_ERR("Encrypt data error %d", err); | |
79 | ||
80 | return err; | |
81 | } | |
82 | ||
83 | static int smp_c1(struct crypto_blkcipher *tfm, u8 k[16], u8 r[16], | |
84 | u8 preq[7], u8 pres[7], u8 _iat, bdaddr_t *ia, | |
85 | u8 _rat, bdaddr_t *ra, u8 res[16]) | |
86 | { | |
87 | u8 p1[16], p2[16]; | |
88 | int err; | |
89 | ||
90 | memset(p1, 0, 16); | |
91 | ||
92 | /* p1 = pres || preq || _rat || _iat */ | |
93 | swap56(pres, p1); | |
94 | swap56(preq, p1 + 7); | |
95 | p1[14] = _rat; | |
96 | p1[15] = _iat; | |
97 | ||
98 | memset(p2, 0, 16); | |
99 | ||
100 | /* p2 = padding || ia || ra */ | |
101 | baswap((bdaddr_t *) (p2 + 4), ia); | |
102 | baswap((bdaddr_t *) (p2 + 10), ra); | |
103 | ||
104 | /* res = r XOR p1 */ | |
105 | u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); | |
106 | ||
107 | /* res = e(k, res) */ | |
108 | err = smp_e(tfm, k, res); | |
109 | if (err) { | |
110 | BT_ERR("Encrypt data error"); | |
111 | return err; | |
112 | } | |
113 | ||
114 | /* res = res XOR p2 */ | |
115 | u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); | |
116 | ||
117 | /* res = e(k, res) */ | |
118 | err = smp_e(tfm, k, res); | |
119 | if (err) | |
120 | BT_ERR("Encrypt data error"); | |
121 | ||
122 | return err; | |
123 | } | |
124 | ||
125 | static int smp_s1(struct crypto_blkcipher *tfm, u8 k[16], | |
126 | u8 r1[16], u8 r2[16], u8 _r[16]) | |
127 | { | |
128 | int err; | |
129 | ||
130 | /* Just least significant octets from r1 and r2 are considered */ | |
131 | memcpy(_r, r1 + 8, 8); | |
132 | memcpy(_r + 8, r2 + 8, 8); | |
133 | ||
134 | err = smp_e(tfm, k, _r); | |
135 | if (err) | |
136 | BT_ERR("Encrypt data error"); | |
137 | ||
138 | return err; | |
139 | } | |
140 | ||
141 | static int smp_rand(u8 *buf) | |
142 | { | |
143 | get_random_bytes(buf, 16); | |
144 | ||
145 | return 0; | |
146 | } | |
eb492e01 AB |
147 | |
148 | static struct sk_buff *smp_build_cmd(struct l2cap_conn *conn, u8 code, | |
149 | u16 dlen, void *data) | |
150 | { | |
151 | struct sk_buff *skb; | |
152 | struct l2cap_hdr *lh; | |
153 | int len; | |
154 | ||
155 | len = L2CAP_HDR_SIZE + sizeof(code) + dlen; | |
156 | ||
157 | if (len > conn->mtu) | |
158 | return NULL; | |
159 | ||
160 | skb = bt_skb_alloc(len, GFP_ATOMIC); | |
161 | if (!skb) | |
162 | return NULL; | |
163 | ||
164 | lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE); | |
165 | lh->len = cpu_to_le16(sizeof(code) + dlen); | |
166 | lh->cid = cpu_to_le16(L2CAP_CID_SMP); | |
167 | ||
168 | memcpy(skb_put(skb, sizeof(code)), &code, sizeof(code)); | |
169 | ||
170 | memcpy(skb_put(skb, dlen), data, dlen); | |
171 | ||
172 | return skb; | |
173 | } | |
174 | ||
175 | static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) | |
176 | { | |
177 | struct sk_buff *skb = smp_build_cmd(conn, code, len, data); | |
178 | ||
179 | BT_DBG("code 0x%2.2x", code); | |
180 | ||
181 | if (!skb) | |
182 | return; | |
183 | ||
184 | hci_send_acl(conn->hcon, skb, 0); | |
e2dcd113 VCG |
185 | |
186 | mod_timer(&conn->security_timer, jiffies + | |
187 | msecs_to_jiffies(SMP_TIMEOUT)); | |
eb492e01 AB |
188 | } |
189 | ||
da85e5e5 VCG |
190 | static __u8 seclevel_to_authreq(__u8 level) |
191 | { | |
192 | switch (level) { | |
193 | case BT_SECURITY_HIGH: | |
194 | /* Right now we don't support bonding */ | |
195 | return SMP_AUTH_MITM; | |
196 | ||
197 | default: | |
198 | return SMP_AUTH_NONE; | |
199 | } | |
200 | } | |
201 | ||
b8e66eac | 202 | static void build_pairing_cmd(struct l2cap_conn *conn, |
54790f73 VCG |
203 | struct smp_cmd_pairing *req, |
204 | struct smp_cmd_pairing *rsp, | |
205 | __u8 authreq) | |
b8e66eac | 206 | { |
54790f73 VCG |
207 | u8 dist_keys; |
208 | ||
209 | dist_keys = 0; | |
210 | if (test_bit(HCI_PAIRABLE, &conn->hcon->hdev->flags)) { | |
211 | dist_keys = SMP_DIST_ENC_KEY | SMP_DIST_ID_KEY | SMP_DIST_SIGN; | |
212 | authreq |= SMP_AUTH_BONDING; | |
213 | } | |
214 | ||
215 | if (rsp == NULL) { | |
216 | req->io_capability = conn->hcon->io_capability; | |
217 | req->oob_flag = SMP_OOB_NOT_PRESENT; | |
218 | req->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
219 | req->init_key_dist = dist_keys; | |
220 | req->resp_key_dist = dist_keys; | |
221 | req->auth_req = authreq; | |
222 | return; | |
223 | } | |
224 | ||
225 | rsp->io_capability = conn->hcon->io_capability; | |
226 | rsp->oob_flag = SMP_OOB_NOT_PRESENT; | |
227 | rsp->max_key_size = SMP_MAX_ENC_KEY_SIZE; | |
228 | rsp->init_key_dist = req->init_key_dist & dist_keys; | |
229 | rsp->resp_key_dist = req->resp_key_dist & dist_keys; | |
230 | rsp->auth_req = authreq; | |
b8e66eac VCG |
231 | } |
232 | ||
3158c50c VCG |
233 | static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) |
234 | { | |
1c1def09 VCG |
235 | struct smp_chan *smp = conn->smp_chan; |
236 | ||
3158c50c VCG |
237 | if ((max_key_size > SMP_MAX_ENC_KEY_SIZE) || |
238 | (max_key_size < SMP_MIN_ENC_KEY_SIZE)) | |
239 | return SMP_ENC_KEY_SIZE; | |
240 | ||
1c1def09 | 241 | smp->smp_key_size = max_key_size; |
3158c50c VCG |
242 | |
243 | return 0; | |
244 | } | |
245 | ||
da85e5e5 | 246 | static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 247 | { |
3158c50c | 248 | struct smp_cmd_pairing rsp, *req = (void *) skb->data; |
1c1def09 | 249 | struct smp_chan *smp = conn->smp_chan; |
3158c50c | 250 | u8 key_size; |
88ba43b6 AB |
251 | |
252 | BT_DBG("conn %p", conn); | |
253 | ||
d26a2345 VCG |
254 | if (!test_and_set_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
255 | hci_conn_hold(conn->hcon); | |
256 | ||
1c1def09 VCG |
257 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
258 | memcpy(&smp->preq[1], req, sizeof(*req)); | |
3158c50c | 259 | skb_pull(skb, sizeof(*req)); |
88ba43b6 | 260 | |
3158c50c | 261 | if (req->oob_flag) |
da85e5e5 VCG |
262 | return SMP_OOB_NOT_AVAIL; |
263 | ||
264 | /* We didn't start the pairing, so no requirements */ | |
54790f73 | 265 | build_pairing_cmd(conn, req, &rsp, SMP_AUTH_NONE); |
3158c50c VCG |
266 | |
267 | key_size = min(req->max_key_size, rsp.max_key_size); | |
268 | if (check_enc_key_size(conn, key_size)) | |
269 | return SMP_ENC_KEY_SIZE; | |
88ba43b6 | 270 | |
7d24ddcc | 271 | /* Just works */ |
1c1def09 | 272 | memset(smp->tk, 0, sizeof(smp->tk)); |
7d24ddcc | 273 | |
1c1def09 VCG |
274 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
275 | memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); | |
f01ead31 | 276 | |
3158c50c | 277 | smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); |
da85e5e5 VCG |
278 | |
279 | return 0; | |
88ba43b6 AB |
280 | } |
281 | ||
da85e5e5 | 282 | static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 283 | { |
3158c50c | 284 | struct smp_cmd_pairing *req, *rsp = (void *) skb->data; |
88ba43b6 | 285 | struct smp_cmd_pairing_confirm cp; |
1c1def09 VCG |
286 | struct smp_chan *smp = conn->smp_chan; |
287 | struct crypto_blkcipher *tfm = smp->tfm; | |
288 | ||
7d24ddcc | 289 | int ret; |
3158c50c | 290 | u8 res[16], key_size; |
88ba43b6 AB |
291 | |
292 | BT_DBG("conn %p", conn); | |
293 | ||
3158c50c VCG |
294 | skb_pull(skb, sizeof(*rsp)); |
295 | ||
1c1def09 | 296 | req = (void *) &smp->preq[1]; |
da85e5e5 | 297 | |
3158c50c VCG |
298 | key_size = min(req->max_key_size, rsp->max_key_size); |
299 | if (check_enc_key_size(conn, key_size)) | |
300 | return SMP_ENC_KEY_SIZE; | |
301 | ||
302 | if (rsp->oob_flag) | |
da85e5e5 VCG |
303 | return SMP_OOB_NOT_AVAIL; |
304 | ||
7d24ddcc | 305 | /* Just works */ |
1c1def09 | 306 | memset(smp->tk, 0, sizeof(smp->tk)); |
88ba43b6 | 307 | |
1c1def09 VCG |
308 | smp->prsp[0] = SMP_CMD_PAIRING_RSP; |
309 | memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); | |
f01ead31 | 310 | |
1c1def09 | 311 | ret = smp_rand(smp->prnd); |
7d24ddcc | 312 | if (ret) |
da85e5e5 | 313 | return SMP_UNSPECIFIED; |
7d24ddcc | 314 | |
1c1def09 | 315 | ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, 0, |
7d24ddcc AB |
316 | conn->src, conn->hcon->dst_type, conn->dst, res); |
317 | if (ret) | |
da85e5e5 | 318 | return SMP_UNSPECIFIED; |
7d24ddcc AB |
319 | |
320 | swap128(res, cp.confirm_val); | |
321 | ||
88ba43b6 | 322 | smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); |
da85e5e5 VCG |
323 | |
324 | return 0; | |
88ba43b6 AB |
325 | } |
326 | ||
da85e5e5 | 327 | static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 328 | { |
1c1def09 VCG |
329 | struct smp_chan *smp = conn->smp_chan; |
330 | struct crypto_blkcipher *tfm = smp->tfm; | |
7d24ddcc | 331 | |
88ba43b6 AB |
332 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); |
333 | ||
1c1def09 VCG |
334 | memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); |
335 | skb_pull(skb, sizeof(smp->pcnf)); | |
88ba43b6 | 336 | |
7d24ddcc AB |
337 | if (conn->hcon->out) { |
338 | u8 random[16]; | |
88ba43b6 | 339 | |
1c1def09 | 340 | swap128(smp->prnd, random); |
88ba43b6 | 341 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(random), |
7d24ddcc | 342 | random); |
88ba43b6 | 343 | } else { |
7d24ddcc AB |
344 | struct smp_cmd_pairing_confirm cp; |
345 | int ret; | |
346 | u8 res[16]; | |
88ba43b6 | 347 | |
1c1def09 | 348 | ret = smp_rand(smp->prnd); |
7d24ddcc | 349 | if (ret) |
da85e5e5 | 350 | return SMP_UNSPECIFIED; |
88ba43b6 | 351 | |
1c1def09 | 352 | ret = smp_c1(tfm, smp->tk, smp->prnd, smp->preq, smp->prsp, |
7d24ddcc AB |
353 | conn->hcon->dst_type, conn->dst, |
354 | 0, conn->src, res); | |
355 | if (ret) | |
da85e5e5 | 356 | return SMP_CONFIRM_FAILED; |
7d24ddcc AB |
357 | |
358 | swap128(res, cp.confirm_val); | |
359 | ||
360 | smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); | |
88ba43b6 | 361 | } |
da85e5e5 VCG |
362 | |
363 | return 0; | |
88ba43b6 AB |
364 | } |
365 | ||
da85e5e5 | 366 | static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 | 367 | { |
a7a595f6 | 368 | struct hci_conn *hcon = conn->hcon; |
1c1def09 VCG |
369 | struct smp_chan *smp = conn->smp_chan; |
370 | struct crypto_blkcipher *tfm = smp->tfm; | |
7d24ddcc | 371 | int ret; |
9b3d6740 | 372 | u8 key[16], res[16], random[16], confirm[16]; |
7d24ddcc AB |
373 | |
374 | swap128(skb->data, random); | |
375 | skb_pull(skb, sizeof(random)); | |
376 | ||
377 | if (conn->hcon->out) | |
1c1def09 | 378 | ret = smp_c1(tfm, smp->tk, random, smp->preq, smp->prsp, 0, |
7d24ddcc AB |
379 | conn->src, conn->hcon->dst_type, conn->dst, |
380 | res); | |
381 | else | |
1c1def09 | 382 | ret = smp_c1(tfm, smp->tk, random, smp->preq, smp->prsp, |
7d24ddcc AB |
383 | conn->hcon->dst_type, conn->dst, 0, conn->src, |
384 | res); | |
385 | if (ret) | |
da85e5e5 | 386 | return SMP_UNSPECIFIED; |
88ba43b6 AB |
387 | |
388 | BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); | |
389 | ||
7d24ddcc AB |
390 | swap128(res, confirm); |
391 | ||
1c1def09 | 392 | if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) { |
7d24ddcc | 393 | BT_ERR("Pairing failed (confirmation values mismatch)"); |
da85e5e5 | 394 | return SMP_CONFIRM_FAILED; |
7d24ddcc | 395 | } |
88ba43b6 AB |
396 | |
397 | if (conn->hcon->out) { | |
e7e62c85 | 398 | u8 stk[16], rand[8]; |
a7a595f6 | 399 | __le16 ediv; |
e7e62c85 VCG |
400 | |
401 | memset(rand, 0, sizeof(rand)); | |
402 | ediv = 0; | |
a7a595f6 | 403 | |
1c1def09 | 404 | smp_s1(tfm, smp->tk, random, smp->prnd, key); |
e7e62c85 | 405 | swap128(key, stk); |
7d24ddcc | 406 | |
1c1def09 VCG |
407 | memset(stk + smp->smp_key_size, 0, |
408 | SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); | |
3158c50c | 409 | |
d26a2345 VCG |
410 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->pend)) |
411 | return SMP_UNSPECIFIED; | |
412 | ||
e7e62c85 | 413 | hci_le_start_enc(hcon, ediv, rand, stk); |
1c1def09 | 414 | hcon->enc_key_size = smp->smp_key_size; |
e7e62c85 VCG |
415 | } else { |
416 | u8 stk[16], r[16], rand[8]; | |
417 | __le16 ediv; | |
418 | ||
a7a595f6 VCG |
419 | memset(rand, 0, sizeof(rand)); |
420 | ediv = 0; | |
7d24ddcc | 421 | |
1c1def09 | 422 | swap128(smp->prnd, r); |
7d24ddcc AB |
423 | smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(r), r); |
424 | ||
1c1def09 | 425 | smp_s1(tfm, smp->tk, smp->prnd, random, key); |
e7e62c85 | 426 | swap128(key, stk); |
3158c50c | 427 | |
1c1def09 VCG |
428 | memset(stk + smp->smp_key_size, 0, |
429 | SMP_MAX_ENC_KEY_SIZE - smp->smp_key_size); | |
e7e62c85 | 430 | |
1c1def09 | 431 | hci_add_ltk(conn->hcon->hdev, 0, conn->dst, smp->smp_key_size, |
726b4ffc | 432 | ediv, rand, stk); |
88ba43b6 | 433 | } |
da85e5e5 VCG |
434 | |
435 | return 0; | |
88ba43b6 AB |
436 | } |
437 | ||
da85e5e5 | 438 | static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) |
88ba43b6 AB |
439 | { |
440 | struct smp_cmd_security_req *rp = (void *) skb->data; | |
441 | struct smp_cmd_pairing cp; | |
f1cb9af5 | 442 | struct hci_conn *hcon = conn->hcon; |
1c1def09 | 443 | struct smp_chan *smp = conn->smp_chan; |
88ba43b6 AB |
444 | |
445 | BT_DBG("conn %p", conn); | |
446 | ||
d26a2345 | 447 | if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) |
da85e5e5 | 448 | return 0; |
f1cb9af5 | 449 | |
d26a2345 VCG |
450 | hci_conn_hold(hcon); |
451 | ||
88ba43b6 | 452 | skb_pull(skb, sizeof(*rp)); |
88ba43b6 | 453 | |
da85e5e5 | 454 | memset(&cp, 0, sizeof(cp)); |
54790f73 | 455 | build_pairing_cmd(conn, &cp, NULL, rp->auth_req); |
88ba43b6 | 456 | |
1c1def09 VCG |
457 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
458 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 459 | |
88ba43b6 | 460 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
f1cb9af5 | 461 | |
da85e5e5 | 462 | return 0; |
88ba43b6 AB |
463 | } |
464 | ||
eb492e01 AB |
465 | int smp_conn_security(struct l2cap_conn *conn, __u8 sec_level) |
466 | { | |
3a0259bb | 467 | struct hci_conn *hcon = conn->hcon; |
1c1def09 | 468 | struct smp_chan *smp = conn->smp_chan; |
eb492e01 AB |
469 | __u8 authreq; |
470 | ||
3a0259bb VCG |
471 | BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); |
472 | ||
2e65c9d2 AG |
473 | if (!lmp_host_le_capable(hcon->hdev)) |
474 | return 1; | |
475 | ||
f1cb9af5 VCG |
476 | if (sec_level == BT_SECURITY_LOW) |
477 | return 1; | |
eb492e01 | 478 | |
f1cb9af5 | 479 | if (hcon->sec_level >= sec_level) |
eb492e01 | 480 | return 1; |
f1cb9af5 | 481 | |
3a0259bb | 482 | if (hcon->link_mode & HCI_LM_MASTER) { |
02bc7455 VCG |
483 | struct link_key *key; |
484 | ||
485 | key = hci_find_link_key_type(hcon->hdev, conn->dst, | |
486 | HCI_LK_SMP_LTK); | |
487 | if (key) { | |
488 | struct key_master_id *master = (void *) key->data; | |
489 | ||
d26a2345 VCG |
490 | if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, |
491 | &hcon->pend)) | |
492 | goto done; | |
493 | ||
02bc7455 VCG |
494 | hci_le_start_enc(hcon, master->ediv, master->rand, |
495 | key->val); | |
726b4ffc VCG |
496 | hcon->enc_key_size = key->pin_len; |
497 | ||
02bc7455 VCG |
498 | goto done; |
499 | } | |
d26a2345 VCG |
500 | } |
501 | ||
502 | if (test_and_set_bit(HCI_CONN_LE_SMP_PEND, &hcon->pend)) | |
503 | return 0; | |
504 | ||
505 | /* While SMP is going on */ | |
506 | hci_conn_hold(hcon); | |
507 | ||
508 | authreq = seclevel_to_authreq(sec_level); | |
509 | ||
510 | if (hcon->link_mode & HCI_LM_MASTER) { | |
511 | struct smp_cmd_pairing cp; | |
f01ead31 | 512 | |
54790f73 | 513 | build_pairing_cmd(conn, &cp, NULL, authreq); |
1c1def09 VCG |
514 | smp->preq[0] = SMP_CMD_PAIRING_REQ; |
515 | memcpy(&smp->preq[1], &cp, sizeof(cp)); | |
f01ead31 | 516 | |
eb492e01 AB |
517 | smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); |
518 | } else { | |
519 | struct smp_cmd_security_req cp; | |
520 | cp.auth_req = authreq; | |
521 | smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); | |
522 | } | |
523 | ||
02bc7455 | 524 | done: |
f1cb9af5 | 525 | hcon->pending_sec_level = sec_level; |
f1cb9af5 | 526 | |
eb492e01 AB |
527 | return 0; |
528 | } | |
529 | ||
7034b911 VCG |
530 | static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) |
531 | { | |
16b90839 | 532 | struct smp_cmd_encrypt_info *rp = (void *) skb->data; |
1c1def09 | 533 | struct smp_chan *smp = conn->smp_chan; |
16b90839 VCG |
534 | |
535 | skb_pull(skb, sizeof(*rp)); | |
536 | ||
1c1def09 | 537 | memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); |
16b90839 | 538 | |
7034b911 VCG |
539 | return 0; |
540 | } | |
541 | ||
542 | static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) | |
543 | { | |
16b90839 | 544 | struct smp_cmd_master_ident *rp = (void *) skb->data; |
1c1def09 | 545 | struct smp_chan *smp = conn->smp_chan; |
16b90839 VCG |
546 | |
547 | skb_pull(skb, sizeof(*rp)); | |
7034b911 | 548 | |
1c1def09 VCG |
549 | hci_add_ltk(conn->hcon->hdev, 1, conn->src, smp->smp_key_size, |
550 | rp->ediv, rp->rand, smp->tk); | |
7034b911 VCG |
551 | |
552 | smp_distribute_keys(conn, 1); | |
553 | ||
554 | return 0; | |
555 | } | |
556 | ||
eb492e01 AB |
557 | int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb) |
558 | { | |
559 | __u8 code = skb->data[0]; | |
560 | __u8 reason; | |
561 | int err = 0; | |
562 | ||
2e65c9d2 AG |
563 | if (!lmp_host_le_capable(conn->hcon->hdev)) { |
564 | err = -ENOTSUPP; | |
565 | reason = SMP_PAIRING_NOTSUPP; | |
566 | goto done; | |
567 | } | |
568 | ||
eb492e01 AB |
569 | skb_pull(skb, sizeof(code)); |
570 | ||
571 | switch (code) { | |
572 | case SMP_CMD_PAIRING_REQ: | |
da85e5e5 | 573 | reason = smp_cmd_pairing_req(conn, skb); |
eb492e01 AB |
574 | break; |
575 | ||
576 | case SMP_CMD_PAIRING_FAIL: | |
da85e5e5 VCG |
577 | reason = 0; |
578 | err = -EPERM; | |
eb492e01 AB |
579 | break; |
580 | ||
581 | case SMP_CMD_PAIRING_RSP: | |
da85e5e5 | 582 | reason = smp_cmd_pairing_rsp(conn, skb); |
88ba43b6 AB |
583 | break; |
584 | ||
585 | case SMP_CMD_SECURITY_REQ: | |
da85e5e5 | 586 | reason = smp_cmd_security_req(conn, skb); |
88ba43b6 AB |
587 | break; |
588 | ||
eb492e01 | 589 | case SMP_CMD_PAIRING_CONFIRM: |
da85e5e5 | 590 | reason = smp_cmd_pairing_confirm(conn, skb); |
88ba43b6 AB |
591 | break; |
592 | ||
eb492e01 | 593 | case SMP_CMD_PAIRING_RANDOM: |
da85e5e5 | 594 | reason = smp_cmd_pairing_random(conn, skb); |
88ba43b6 AB |
595 | break; |
596 | ||
eb492e01 | 597 | case SMP_CMD_ENCRYPT_INFO: |
7034b911 VCG |
598 | reason = smp_cmd_encrypt_info(conn, skb); |
599 | break; | |
600 | ||
eb492e01 | 601 | case SMP_CMD_MASTER_IDENT: |
7034b911 VCG |
602 | reason = smp_cmd_master_ident(conn, skb); |
603 | break; | |
604 | ||
eb492e01 AB |
605 | case SMP_CMD_IDENT_INFO: |
606 | case SMP_CMD_IDENT_ADDR_INFO: | |
607 | case SMP_CMD_SIGN_INFO: | |
7034b911 VCG |
608 | /* Just ignored */ |
609 | reason = 0; | |
610 | break; | |
611 | ||
eb492e01 AB |
612 | default: |
613 | BT_DBG("Unknown command code 0x%2.2x", code); | |
614 | ||
615 | reason = SMP_CMD_NOTSUPP; | |
eb492e01 | 616 | err = -EOPNOTSUPP; |
3a0259bb | 617 | goto done; |
eb492e01 AB |
618 | } |
619 | ||
3a0259bb VCG |
620 | done: |
621 | if (reason) | |
622 | smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), | |
623 | &reason); | |
624 | ||
eb492e01 AB |
625 | kfree_skb(skb); |
626 | return err; | |
627 | } | |
7034b911 VCG |
628 | |
629 | int smp_distribute_keys(struct l2cap_conn *conn, __u8 force) | |
630 | { | |
631 | struct smp_cmd_pairing *req, *rsp; | |
1c1def09 | 632 | struct smp_chan *smp = conn->smp_chan; |
7034b911 VCG |
633 | __u8 *keydist; |
634 | ||
635 | BT_DBG("conn %p force %d", conn, force); | |
636 | ||
d26a2345 VCG |
637 | if (!test_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend)) |
638 | return 0; | |
639 | ||
1c1def09 | 640 | rsp = (void *) &smp->prsp[1]; |
7034b911 VCG |
641 | |
642 | /* The responder sends its keys first */ | |
643 | if (!force && conn->hcon->out && (rsp->resp_key_dist & 0x07)) | |
644 | return 0; | |
645 | ||
1c1def09 | 646 | req = (void *) &smp->preq[1]; |
7034b911 VCG |
647 | |
648 | if (conn->hcon->out) { | |
649 | keydist = &rsp->init_key_dist; | |
650 | *keydist &= req->init_key_dist; | |
651 | } else { | |
652 | keydist = &rsp->resp_key_dist; | |
653 | *keydist &= req->resp_key_dist; | |
654 | } | |
655 | ||
656 | ||
657 | BT_DBG("keydist 0x%x", *keydist); | |
658 | ||
659 | if (*keydist & SMP_DIST_ENC_KEY) { | |
660 | struct smp_cmd_encrypt_info enc; | |
661 | struct smp_cmd_master_ident ident; | |
662 | __le16 ediv; | |
663 | ||
664 | get_random_bytes(enc.ltk, sizeof(enc.ltk)); | |
665 | get_random_bytes(&ediv, sizeof(ediv)); | |
666 | get_random_bytes(ident.rand, sizeof(ident.rand)); | |
667 | ||
668 | smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); | |
669 | ||
1c1def09 | 670 | hci_add_ltk(conn->hcon->hdev, 1, conn->dst, smp->smp_key_size, |
726b4ffc | 671 | ediv, ident.rand, enc.ltk); |
16b90839 | 672 | |
7034b911 VCG |
673 | ident.ediv = cpu_to_le16(ediv); |
674 | ||
675 | smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); | |
676 | ||
677 | *keydist &= ~SMP_DIST_ENC_KEY; | |
678 | } | |
679 | ||
680 | if (*keydist & SMP_DIST_ID_KEY) { | |
681 | struct smp_cmd_ident_addr_info addrinfo; | |
682 | struct smp_cmd_ident_info idinfo; | |
683 | ||
684 | /* Send a dummy key */ | |
685 | get_random_bytes(idinfo.irk, sizeof(idinfo.irk)); | |
686 | ||
687 | smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); | |
688 | ||
689 | /* Just public address */ | |
690 | memset(&addrinfo, 0, sizeof(addrinfo)); | |
691 | bacpy(&addrinfo.bdaddr, conn->src); | |
692 | ||
693 | smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), | |
694 | &addrinfo); | |
695 | ||
696 | *keydist &= ~SMP_DIST_ID_KEY; | |
697 | } | |
698 | ||
699 | if (*keydist & SMP_DIST_SIGN) { | |
700 | struct smp_cmd_sign_info sign; | |
701 | ||
702 | /* Send a dummy key */ | |
703 | get_random_bytes(sign.csrk, sizeof(sign.csrk)); | |
704 | ||
705 | smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); | |
706 | ||
707 | *keydist &= ~SMP_DIST_SIGN; | |
708 | } | |
709 | ||
d26a2345 VCG |
710 | if (conn->hcon->out || force) { |
711 | clear_bit(HCI_CONN_LE_SMP_PEND, &conn->hcon->pend); | |
712 | del_timer(&conn->security_timer); | |
713 | hci_conn_put(conn->hcon); | |
714 | } | |
715 | ||
7034b911 VCG |
716 | return 0; |
717 | } |