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 <linux/debugfs.h> 24#include <linux/scatterlist.h> 25#include <linux/crypto.h> 26#include <crypto/aes.h> 27#include <crypto/algapi.h> 28#include <crypto/b128ops.h> 29#include <crypto/hash.h> 30#include <crypto/kpp.h> 31 32#include <net/bluetooth/bluetooth.h> 33#include <net/bluetooth/hci_core.h> 34#include <net/bluetooth/l2cap.h> 35#include <net/bluetooth/mgmt.h> 36 37#include "ecdh_helper.h" 38#include "smp.h" 39 40#define SMP_DEV(hdev) \ 41 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data) 42 43/* Low-level debug macros to be used for stuff that we don't want 44 * accidentially in dmesg, i.e. the values of the various crypto keys 45 * and the inputs & outputs of crypto functions. 46 */ 47#ifdef DEBUG 48#define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \ 49 ##__VA_ARGS__) 50#else 51#define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \ 52 ##__VA_ARGS__) 53#endif 54 55#define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) 56 57/* Keys which are not distributed with Secure Connections */ 58#define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY); 59 60#define SMP_TIMEOUT msecs_to_jiffies(30000) 61 62#define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \ 63 0x3f : 0x07) 64#define KEY_DIST_MASK 0x07 65 66/* Maximum message length that can be passed to aes_cmac */ 67#define CMAC_MSG_MAX 80 68 69enum { 70 SMP_FLAG_TK_VALID, 71 SMP_FLAG_CFM_PENDING, 72 SMP_FLAG_MITM_AUTH, 73 SMP_FLAG_COMPLETE, 74 SMP_FLAG_INITIATOR, 75 SMP_FLAG_SC, 76 SMP_FLAG_REMOTE_PK, 77 SMP_FLAG_DEBUG_KEY, 78 SMP_FLAG_WAIT_USER, 79 SMP_FLAG_DHKEY_PENDING, 80 SMP_FLAG_REMOTE_OOB, 81 SMP_FLAG_LOCAL_OOB, 82 SMP_FLAG_CT2, 83}; 84 85struct smp_dev { 86 /* Secure Connections OOB data */ 87 bool local_oob; 88 u8 local_pk[64]; 89 u8 local_rand[16]; 90 bool debug_key; 91 92 struct crypto_shash *tfm_cmac; 93 struct crypto_kpp *tfm_ecdh; 94}; 95 96struct smp_chan { 97 struct l2cap_conn *conn; 98 struct delayed_work security_timer; 99 unsigned long allow_cmd; /* Bitmask of allowed commands */ 100 101 u8 preq[7]; /* SMP Pairing Request */ 102 u8 prsp[7]; /* SMP Pairing Response */ 103 u8 prnd[16]; /* SMP Pairing Random (local) */ 104 u8 rrnd[16]; /* SMP Pairing Random (remote) */ 105 u8 pcnf[16]; /* SMP Pairing Confirm */ 106 u8 tk[16]; /* SMP Temporary Key */ 107 u8 rr[16]; /* Remote OOB ra/rb value */ 108 u8 lr[16]; /* Local OOB ra/rb value */ 109 u8 enc_key_size; 110 u8 remote_key_dist; 111 bdaddr_t id_addr; 112 u8 id_addr_type; 113 u8 irk[16]; 114 struct smp_csrk *csrk; 115 struct smp_csrk *responder_csrk; 116 struct smp_ltk *ltk; 117 struct smp_ltk *responder_ltk; 118 struct smp_irk *remote_irk; 119 u8 *link_key; 120 unsigned long flags; 121 u8 method; 122 u8 passkey_round; 123 124 /* Secure Connections variables */ 125 u8 local_pk[64]; 126 u8 remote_pk[64]; 127 u8 dhkey[32]; 128 u8 mackey[16]; 129 130 struct crypto_shash *tfm_cmac; 131 struct crypto_kpp *tfm_ecdh; 132}; 133 134/* These debug key values are defined in the SMP section of the core 135 * specification. debug_pk is the public debug key and debug_sk the 136 * private debug key. 137 */ 138static const u8 debug_pk[64] = { 139 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 140 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 141 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 142 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 143 144 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 145 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 146 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 147 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 148}; 149 150static const u8 debug_sk[32] = { 151 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 152 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 153 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 154 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 155}; 156 157static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 158{ 159 size_t i; 160 161 for (i = 0; i < len; i++) 162 dst[len - 1 - i] = src[i]; 163} 164 165/* The following functions map to the LE SC SMP crypto functions 166 * AES-CMAC, f4, f5, f6, g2 and h6. 167 */ 168 169static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 170 size_t len, u8 mac[16]) 171{ 172 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 173 int err; 174 175 if (len > CMAC_MSG_MAX) 176 return -EFBIG; 177 178 if (!tfm) { 179 BT_ERR("tfm %p", tfm); 180 return -EINVAL; 181 } 182 183 /* Swap key and message from LSB to MSB */ 184 swap_buf(k, tmp, 16); 185 swap_buf(m, msg_msb, len); 186 187 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 188 SMP_DBG("key %16phN", k); 189 190 err = crypto_shash_setkey(tfm, tmp, 16); 191 if (err) { 192 BT_ERR("cipher setkey failed: %d", err); 193 return err; 194 } 195 196 err = crypto_shash_tfm_digest(tfm, msg_msb, len, mac_msb); 197 if (err) { 198 BT_ERR("Hash computation error %d", err); 199 return err; 200 } 201 202 swap_buf(mac_msb, mac, 16); 203 204 SMP_DBG("mac %16phN", mac); 205 206 return 0; 207} 208 209static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 210 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 211{ 212 u8 m[65]; 213 int err; 214 215 SMP_DBG("u %32phN", u); 216 SMP_DBG("v %32phN", v); 217 SMP_DBG("x %16phN z %02x", x, z); 218 219 m[0] = z; 220 memcpy(m + 1, v, 32); 221 memcpy(m + 33, u, 32); 222 223 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 224 if (err) 225 return err; 226 227 SMP_DBG("res %16phN", res); 228 229 return err; 230} 231 232static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 233 const u8 n1[16], const u8 n2[16], const u8 a1[7], 234 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 235{ 236 /* The btle, salt and length "magic" values are as defined in 237 * the SMP section of the Bluetooth core specification. In ASCII 238 * the btle value ends up being 'btle'. The salt is just a 239 * random number whereas length is the value 256 in little 240 * endian format. 241 */ 242 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 243 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 244 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 245 const u8 length[2] = { 0x00, 0x01 }; 246 u8 m[53], t[16]; 247 int err; 248 249 SMP_DBG("w %32phN", w); 250 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 251 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 252 253 err = aes_cmac(tfm_cmac, salt, w, 32, t); 254 if (err) 255 return err; 256 257 SMP_DBG("t %16phN", t); 258 259 memcpy(m, length, 2); 260 memcpy(m + 2, a2, 7); 261 memcpy(m + 9, a1, 7); 262 memcpy(m + 16, n2, 16); 263 memcpy(m + 32, n1, 16); 264 memcpy(m + 48, btle, 4); 265 266 m[52] = 0; /* Counter */ 267 268 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 269 if (err) 270 return err; 271 272 SMP_DBG("mackey %16phN", mackey); 273 274 m[52] = 1; /* Counter */ 275 276 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 277 if (err) 278 return err; 279 280 SMP_DBG("ltk %16phN", ltk); 281 282 return 0; 283} 284 285static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 286 const u8 n1[16], const u8 n2[16], const u8 r[16], 287 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 288 u8 res[16]) 289{ 290 u8 m[65]; 291 int err; 292 293 SMP_DBG("w %16phN", w); 294 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 295 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 296 297 memcpy(m, a2, 7); 298 memcpy(m + 7, a1, 7); 299 memcpy(m + 14, io_cap, 3); 300 memcpy(m + 17, r, 16); 301 memcpy(m + 33, n2, 16); 302 memcpy(m + 49, n1, 16); 303 304 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 305 if (err) 306 return err; 307 308 SMP_DBG("res %16phN", res); 309 310 return err; 311} 312 313static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 314 const u8 x[16], const u8 y[16], u32 *val) 315{ 316 u8 m[80], tmp[16]; 317 int err; 318 319 SMP_DBG("u %32phN", u); 320 SMP_DBG("v %32phN", v); 321 SMP_DBG("x %16phN y %16phN", x, y); 322 323 memcpy(m, y, 16); 324 memcpy(m + 16, v, 32); 325 memcpy(m + 48, u, 32); 326 327 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 328 if (err) 329 return err; 330 331 *val = get_unaligned_le32(tmp); 332 *val %= 1000000; 333 334 SMP_DBG("val %06u", *val); 335 336 return 0; 337} 338 339static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 340 const u8 key_id[4], u8 res[16]) 341{ 342 int err; 343 344 SMP_DBG("w %16phN key_id %4phN", w, key_id); 345 346 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 347 if (err) 348 return err; 349 350 SMP_DBG("res %16phN", res); 351 352 return err; 353} 354 355static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 356 const u8 salt[16], u8 res[16]) 357{ 358 int err; 359 360 SMP_DBG("w %16phN salt %16phN", w, salt); 361 362 err = aes_cmac(tfm_cmac, salt, w, 16, res); 363 if (err) 364 return err; 365 366 SMP_DBG("res %16phN", res); 367 368 return err; 369} 370 371/* The following functions map to the legacy SMP crypto functions e, c1, 372 * s1 and ah. 373 */ 374 375static int smp_e(const u8 *k, u8 *r) 376{ 377 struct crypto_aes_ctx ctx; 378 uint8_t tmp[16], data[16]; 379 int err; 380 381 SMP_DBG("k %16phN r %16phN", k, r); 382 383 /* The most significant octet of key corresponds to k[0] */ 384 swap_buf(k, tmp, 16); 385 386 err = aes_expandkey(&ctx, tmp, 16); 387 if (err) { 388 BT_ERR("cipher setkey failed: %d", err); 389 return err; 390 } 391 392 /* Most significant octet of plaintextData corresponds to data[0] */ 393 swap_buf(r, data, 16); 394 395 aes_encrypt(&ctx, data, data); 396 397 /* Most significant octet of encryptedData corresponds to data[0] */ 398 swap_buf(data, r, 16); 399 400 SMP_DBG("r %16phN", r); 401 402 memzero_explicit(&ctx, sizeof (ctx)); 403 return err; 404} 405 406static int smp_c1(const u8 k[16], 407 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 408 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 409{ 410 u8 p1[16], p2[16]; 411 int err; 412 413 SMP_DBG("k %16phN r %16phN", k, r); 414 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 415 SMP_DBG("preq %7phN pres %7phN", preq, pres); 416 417 memset(p1, 0, 16); 418 419 /* p1 = pres || preq || _rat || _iat */ 420 p1[0] = _iat; 421 p1[1] = _rat; 422 memcpy(p1 + 2, preq, 7); 423 memcpy(p1 + 9, pres, 7); 424 425 SMP_DBG("p1 %16phN", p1); 426 427 /* res = r XOR p1 */ 428 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); 429 430 /* res = e(k, res) */ 431 err = smp_e(k, res); 432 if (err) { 433 BT_ERR("Encrypt data error"); 434 return err; 435 } 436 437 /* p2 = padding || ia || ra */ 438 memcpy(p2, ra, 6); 439 memcpy(p2 + 6, ia, 6); 440 memset(p2 + 12, 0, 4); 441 442 SMP_DBG("p2 %16phN", p2); 443 444 /* res = res XOR p2 */ 445 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); 446 447 /* res = e(k, res) */ 448 err = smp_e(k, res); 449 if (err) 450 BT_ERR("Encrypt data error"); 451 452 return err; 453} 454 455static int smp_s1(const u8 k[16], 456 const u8 r1[16], const u8 r2[16], u8 _r[16]) 457{ 458 int err; 459 460 /* Just least significant octets from r1 and r2 are considered */ 461 memcpy(_r, r2, 8); 462 memcpy(_r + 8, r1, 8); 463 464 err = smp_e(k, _r); 465 if (err) 466 BT_ERR("Encrypt data error"); 467 468 return err; 469} 470 471static int smp_ah(const u8 irk[16], const u8 r[3], u8 res[3]) 472{ 473 u8 _res[16]; 474 int err; 475 476 /* r' = padding || r */ 477 memcpy(_res, r, 3); 478 memset(_res + 3, 0, 13); 479 480 err = smp_e(irk, _res); 481 if (err) { 482 BT_ERR("Encrypt error"); 483 return err; 484 } 485 486 /* The output of the random address function ah is: 487 * ah(k, r) = e(k, r') mod 2^24 488 * The output of the security function e is then truncated to 24 bits 489 * by taking the least significant 24 bits of the output of e as the 490 * result of ah. 491 */ 492 memcpy(res, _res, 3); 493 494 return 0; 495} 496 497bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 498 const bdaddr_t *bdaddr) 499{ 500 struct l2cap_chan *chan = hdev->smp_data; 501 u8 hash[3]; 502 int err; 503 504 if (!chan || !chan->data) 505 return false; 506 507 bt_dev_dbg(hdev, "RPA %pMR IRK %*phN", bdaddr, 16, irk); 508 509 err = smp_ah(irk, &bdaddr->b[3], hash); 510 if (err) 511 return false; 512 513 return !crypto_memneq(bdaddr->b, hash, 3); 514} 515 516int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 517{ 518 struct l2cap_chan *chan = hdev->smp_data; 519 int err; 520 521 if (!chan || !chan->data) 522 return -EOPNOTSUPP; 523 524 get_random_bytes(&rpa->b[3], 3); 525 526 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 527 rpa->b[5] |= 0x40; /* Set second most significant bit */ 528 529 err = smp_ah(irk, &rpa->b[3], rpa->b); 530 if (err < 0) 531 return err; 532 533 bt_dev_dbg(hdev, "RPA %pMR", rpa); 534 535 return 0; 536} 537 538int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 539{ 540 struct l2cap_chan *chan = hdev->smp_data; 541 struct smp_dev *smp; 542 int err; 543 544 if (!chan || !chan->data) 545 return -EOPNOTSUPP; 546 547 smp = chan->data; 548 549 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 550 bt_dev_dbg(hdev, "Using debug keys"); 551 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk); 552 if (err) 553 return err; 554 memcpy(smp->local_pk, debug_pk, 64); 555 smp->debug_key = true; 556 } else { 557 while (true) { 558 /* Generate key pair for Secure Connections */ 559 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk); 560 if (err) 561 return err; 562 563 /* This is unlikely, but we need to check that 564 * we didn't accidentially generate a debug key. 565 */ 566 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 567 break; 568 } 569 smp->debug_key = false; 570 } 571 572 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 573 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 574 575 get_random_bytes(smp->local_rand, 16); 576 577 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 578 smp->local_rand, 0, hash); 579 if (err < 0) 580 return err; 581 582 memcpy(rand, smp->local_rand, 16); 583 584 smp->local_oob = true; 585 586 return 0; 587} 588 589static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 590{ 591 struct l2cap_chan *chan = conn->smp; 592 struct smp_chan *smp; 593 struct kvec iv[2]; 594 struct msghdr msg; 595 596 if (!chan) 597 return; 598 599 bt_dev_dbg(conn->hcon->hdev, "code 0x%2.2x", code); 600 601 iv[0].iov_base = &code; 602 iv[0].iov_len = 1; 603 604 iv[1].iov_base = data; 605 iv[1].iov_len = len; 606 607 memset(&msg, 0, sizeof(msg)); 608 609 iov_iter_kvec(&msg.msg_iter, WRITE, iv, 2, 1 + len); 610 611 l2cap_chan_send(chan, &msg, 1 + len); 612 613 if (!chan->data) 614 return; 615 616 smp = chan->data; 617 618 cancel_delayed_work_sync(&smp->security_timer); 619 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 620} 621 622static u8 authreq_to_seclevel(u8 authreq) 623{ 624 if (authreq & SMP_AUTH_MITM) { 625 if (authreq & SMP_AUTH_SC) 626 return BT_SECURITY_FIPS; 627 else 628 return BT_SECURITY_HIGH; 629 } else { 630 return BT_SECURITY_MEDIUM; 631 } 632} 633 634static __u8 seclevel_to_authreq(__u8 sec_level) 635{ 636 switch (sec_level) { 637 case BT_SECURITY_FIPS: 638 case BT_SECURITY_HIGH: 639 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 640 case BT_SECURITY_MEDIUM: 641 return SMP_AUTH_BONDING; 642 default: 643 return SMP_AUTH_NONE; 644 } 645} 646 647static void build_pairing_cmd(struct l2cap_conn *conn, 648 struct smp_cmd_pairing *req, 649 struct smp_cmd_pairing *rsp, __u8 authreq) 650{ 651 struct l2cap_chan *chan = conn->smp; 652 struct smp_chan *smp = chan->data; 653 struct hci_conn *hcon = conn->hcon; 654 struct hci_dev *hdev = hcon->hdev; 655 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 656 657 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 658 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 659 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 660 authreq |= SMP_AUTH_BONDING; 661 } else { 662 authreq &= ~SMP_AUTH_BONDING; 663 } 664 665 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 666 remote_dist |= SMP_DIST_ID_KEY; 667 668 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 669 local_dist |= SMP_DIST_ID_KEY; 670 671 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 672 (authreq & SMP_AUTH_SC)) { 673 struct oob_data *oob_data; 674 u8 bdaddr_type; 675 676 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 677 local_dist |= SMP_DIST_LINK_KEY; 678 remote_dist |= SMP_DIST_LINK_KEY; 679 } 680 681 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 682 bdaddr_type = BDADDR_LE_PUBLIC; 683 else 684 bdaddr_type = BDADDR_LE_RANDOM; 685 686 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 687 bdaddr_type); 688 if (oob_data && oob_data->present) { 689 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 690 oob_flag = SMP_OOB_PRESENT; 691 memcpy(smp->rr, oob_data->rand256, 16); 692 memcpy(smp->pcnf, oob_data->hash256, 16); 693 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 694 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 695 } 696 697 } else { 698 authreq &= ~SMP_AUTH_SC; 699 } 700 701 if (rsp == NULL) { 702 req->io_capability = conn->hcon->io_capability; 703 req->oob_flag = oob_flag; 704 req->max_key_size = hdev->le_max_key_size; 705 req->init_key_dist = local_dist; 706 req->resp_key_dist = remote_dist; 707 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 708 709 smp->remote_key_dist = remote_dist; 710 return; 711 } 712 713 rsp->io_capability = conn->hcon->io_capability; 714 rsp->oob_flag = oob_flag; 715 rsp->max_key_size = hdev->le_max_key_size; 716 rsp->init_key_dist = req->init_key_dist & remote_dist; 717 rsp->resp_key_dist = req->resp_key_dist & local_dist; 718 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 719 720 smp->remote_key_dist = rsp->init_key_dist; 721} 722 723static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 724{ 725 struct l2cap_chan *chan = conn->smp; 726 struct hci_dev *hdev = conn->hcon->hdev; 727 struct smp_chan *smp = chan->data; 728 729 if (conn->hcon->pending_sec_level == BT_SECURITY_FIPS && 730 max_key_size != SMP_MAX_ENC_KEY_SIZE) 731 return SMP_ENC_KEY_SIZE; 732 733 if (max_key_size > hdev->le_max_key_size || 734 max_key_size < SMP_MIN_ENC_KEY_SIZE) 735 return SMP_ENC_KEY_SIZE; 736 737 smp->enc_key_size = max_key_size; 738 739 return 0; 740} 741 742static void smp_chan_destroy(struct l2cap_conn *conn) 743{ 744 struct l2cap_chan *chan = conn->smp; 745 struct smp_chan *smp = chan->data; 746 struct hci_conn *hcon = conn->hcon; 747 bool complete; 748 749 BUG_ON(!smp); 750 751 cancel_delayed_work_sync(&smp->security_timer); 752 753 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 754 mgmt_smp_complete(hcon, complete); 755 756 kfree_sensitive(smp->csrk); 757 kfree_sensitive(smp->responder_csrk); 758 kfree_sensitive(smp->link_key); 759 760 crypto_free_shash(smp->tfm_cmac); 761 crypto_free_kpp(smp->tfm_ecdh); 762 763 /* Ensure that we don't leave any debug key around if debug key 764 * support hasn't been explicitly enabled. 765 */ 766 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 767 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 768 list_del_rcu(&smp->ltk->list); 769 kfree_rcu(smp->ltk, rcu); 770 smp->ltk = NULL; 771 } 772 773 /* If pairing failed clean up any keys we might have */ 774 if (!complete) { 775 if (smp->ltk) { 776 list_del_rcu(&smp->ltk->list); 777 kfree_rcu(smp->ltk, rcu); 778 } 779 780 if (smp->responder_ltk) { 781 list_del_rcu(&smp->responder_ltk->list); 782 kfree_rcu(smp->responder_ltk, rcu); 783 } 784 785 if (smp->remote_irk) { 786 list_del_rcu(&smp->remote_irk->list); 787 kfree_rcu(smp->remote_irk, rcu); 788 } 789 } 790 791 chan->data = NULL; 792 kfree_sensitive(smp); 793 hci_conn_drop(hcon); 794} 795 796static void smp_failure(struct l2cap_conn *conn, u8 reason) 797{ 798 struct hci_conn *hcon = conn->hcon; 799 struct l2cap_chan *chan = conn->smp; 800 801 if (reason) 802 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 803 &reason); 804 805 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 806 807 if (chan->data) 808 smp_chan_destroy(conn); 809} 810 811#define JUST_WORKS 0x00 812#define JUST_CFM 0x01 813#define REQ_PASSKEY 0x02 814#define CFM_PASSKEY 0x03 815#define REQ_OOB 0x04 816#define DSP_PASSKEY 0x05 817#define OVERLAP 0xFF 818 819static const u8 gen_method[5][5] = { 820 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 821 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 822 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 823 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 824 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 825}; 826 827static const u8 sc_method[5][5] = { 828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 829 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 830 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 832 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 833}; 834 835static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 836{ 837 /* If either side has unknown io_caps, use JUST_CFM (which gets 838 * converted later to JUST_WORKS if we're initiators. 839 */ 840 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 841 remote_io > SMP_IO_KEYBOARD_DISPLAY) 842 return JUST_CFM; 843 844 if (test_bit(SMP_FLAG_SC, &smp->flags)) 845 return sc_method[remote_io][local_io]; 846 847 return gen_method[remote_io][local_io]; 848} 849 850static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 851 u8 local_io, u8 remote_io) 852{ 853 struct hci_conn *hcon = conn->hcon; 854 struct l2cap_chan *chan = conn->smp; 855 struct smp_chan *smp = chan->data; 856 u32 passkey = 0; 857 int ret; 858 859 /* Initialize key for JUST WORKS */ 860 memset(smp->tk, 0, sizeof(smp->tk)); 861 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 862 863 bt_dev_dbg(hcon->hdev, "auth:%d lcl:%d rem:%d", auth, local_io, 864 remote_io); 865 866 /* If neither side wants MITM, either "just" confirm an incoming 867 * request or use just-works for outgoing ones. The JUST_CFM 868 * will be converted to JUST_WORKS if necessary later in this 869 * function. If either side has MITM look up the method from the 870 * table. 871 */ 872 if (!(auth & SMP_AUTH_MITM)) 873 smp->method = JUST_CFM; 874 else 875 smp->method = get_auth_method(smp, local_io, remote_io); 876 877 /* Don't confirm locally initiated pairing attempts */ 878 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 879 &smp->flags)) 880 smp->method = JUST_WORKS; 881 882 /* Don't bother user space with no IO capabilities */ 883 if (smp->method == JUST_CFM && 884 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 885 smp->method = JUST_WORKS; 886 887 /* If Just Works, Continue with Zero TK and ask user-space for 888 * confirmation */ 889 if (smp->method == JUST_WORKS) { 890 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 891 hcon->type, 892 hcon->dst_type, 893 passkey, 1); 894 if (ret) 895 return ret; 896 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 897 return 0; 898 } 899 900 /* If this function is used for SC -> legacy fallback we 901 * can only recover the just-works case. 902 */ 903 if (test_bit(SMP_FLAG_SC, &smp->flags)) 904 return -EINVAL; 905 906 /* Not Just Works/Confirm results in MITM Authentication */ 907 if (smp->method != JUST_CFM) { 908 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); 909 if (hcon->pending_sec_level < BT_SECURITY_HIGH) 910 hcon->pending_sec_level = BT_SECURITY_HIGH; 911 } 912 913 /* If both devices have Keyboard-Display I/O, the initiator 914 * Confirms and the responder Enters the passkey. 915 */ 916 if (smp->method == OVERLAP) { 917 if (hcon->role == HCI_ROLE_MASTER) 918 smp->method = CFM_PASSKEY; 919 else 920 smp->method = REQ_PASSKEY; 921 } 922 923 /* Generate random passkey. */ 924 if (smp->method == CFM_PASSKEY) { 925 memset(smp->tk, 0, sizeof(smp->tk)); 926 get_random_bytes(&passkey, sizeof(passkey)); 927 passkey %= 1000000; 928 put_unaligned_le32(passkey, smp->tk); 929 bt_dev_dbg(hcon->hdev, "PassKey: %d", passkey); 930 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 931 } 932 933 if (smp->method == REQ_PASSKEY) 934 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, 935 hcon->type, hcon->dst_type); 936 else if (smp->method == JUST_CFM) 937 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 938 hcon->type, hcon->dst_type, 939 passkey, 1); 940 else 941 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, 942 hcon->type, hcon->dst_type, 943 passkey, 0); 944 945 return ret; 946} 947 948static u8 smp_confirm(struct smp_chan *smp) 949{ 950 struct l2cap_conn *conn = smp->conn; 951 struct smp_cmd_pairing_confirm cp; 952 int ret; 953 954 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 955 956 ret = smp_c1(smp->tk, smp->prnd, smp->preq, smp->prsp, 957 conn->hcon->init_addr_type, &conn->hcon->init_addr, 958 conn->hcon->resp_addr_type, &conn->hcon->resp_addr, 959 cp.confirm_val); 960 if (ret) 961 return SMP_UNSPECIFIED; 962 963 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 964 965 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); 966 967 if (conn->hcon->out) 968 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 969 else 970 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 971 972 return 0; 973} 974 975static u8 smp_random(struct smp_chan *smp) 976{ 977 struct l2cap_conn *conn = smp->conn; 978 struct hci_conn *hcon = conn->hcon; 979 u8 confirm[16]; 980 int ret; 981 982 bt_dev_dbg(conn->hcon->hdev, "conn %p %s", conn, 983 conn->hcon->out ? "initiator" : "responder"); 984 985 ret = smp_c1(smp->tk, smp->rrnd, smp->preq, smp->prsp, 986 hcon->init_addr_type, &hcon->init_addr, 987 hcon->resp_addr_type, &hcon->resp_addr, confirm); 988 if (ret) 989 return SMP_UNSPECIFIED; 990 991 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) { 992 bt_dev_err(hcon->hdev, "pairing failed " 993 "(confirmation values mismatch)"); 994 return SMP_CONFIRM_FAILED; 995 } 996 997 if (hcon->out) { 998 u8 stk[16]; 999 __le64 rand = 0; 1000 __le16 ediv = 0; 1001 1002 smp_s1(smp->tk, smp->rrnd, smp->prnd, stk); 1003 1004 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 1005 return SMP_UNSPECIFIED; 1006 1007 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 1008 hcon->enc_key_size = smp->enc_key_size; 1009 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1010 } else { 1011 u8 stk[16], auth; 1012 __le64 rand = 0; 1013 __le16 ediv = 0; 1014 1015 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1016 smp->prnd); 1017 1018 smp_s1(smp->tk, smp->prnd, smp->rrnd, stk); 1019 1020 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1021 auth = 1; 1022 else 1023 auth = 0; 1024 1025 /* Even though there's no _RESPONDER suffix this is the 1026 * responder STK we're adding for later lookup (the initiator 1027 * STK never needs to be stored). 1028 */ 1029 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1030 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1031 } 1032 1033 return 0; 1034} 1035 1036static void smp_notify_keys(struct l2cap_conn *conn) 1037{ 1038 struct l2cap_chan *chan = conn->smp; 1039 struct smp_chan *smp = chan->data; 1040 struct hci_conn *hcon = conn->hcon; 1041 struct hci_dev *hdev = hcon->hdev; 1042 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1043 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1044 bool persistent; 1045 1046 if (hcon->type == ACL_LINK) { 1047 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1048 persistent = false; 1049 else 1050 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1051 &hcon->flags); 1052 } else { 1053 /* The LTKs, IRKs and CSRKs should be persistent only if 1054 * both sides had the bonding bit set in their 1055 * authentication requests. 1056 */ 1057 persistent = !!((req->auth_req & rsp->auth_req) & 1058 SMP_AUTH_BONDING); 1059 } 1060 1061 if (smp->remote_irk) { 1062 smp->remote_irk->link_type = hcon->type; 1063 mgmt_new_irk(hdev, smp->remote_irk, persistent); 1064 1065 /* Now that user space can be considered to know the 1066 * identity address track the connection based on it 1067 * from now on (assuming this is an LE link). 1068 */ 1069 if (hcon->type == LE_LINK) { 1070 bacpy(&hcon->dst, &smp->remote_irk->bdaddr); 1071 hcon->dst_type = smp->remote_irk->addr_type; 1072 queue_work(hdev->workqueue, &conn->id_addr_update_work); 1073 } 1074 } 1075 1076 if (smp->csrk) { 1077 smp->csrk->link_type = hcon->type; 1078 smp->csrk->bdaddr_type = hcon->dst_type; 1079 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1080 mgmt_new_csrk(hdev, smp->csrk, persistent); 1081 } 1082 1083 if (smp->responder_csrk) { 1084 smp->responder_csrk->link_type = hcon->type; 1085 smp->responder_csrk->bdaddr_type = hcon->dst_type; 1086 bacpy(&smp->responder_csrk->bdaddr, &hcon->dst); 1087 mgmt_new_csrk(hdev, smp->responder_csrk, persistent); 1088 } 1089 1090 if (smp->ltk) { 1091 smp->ltk->link_type = hcon->type; 1092 smp->ltk->bdaddr_type = hcon->dst_type; 1093 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1094 mgmt_new_ltk(hdev, smp->ltk, persistent); 1095 } 1096 1097 if (smp->responder_ltk) { 1098 smp->responder_ltk->link_type = hcon->type; 1099 smp->responder_ltk->bdaddr_type = hcon->dst_type; 1100 bacpy(&smp->responder_ltk->bdaddr, &hcon->dst); 1101 mgmt_new_ltk(hdev, smp->responder_ltk, persistent); 1102 } 1103 1104 if (smp->link_key) { 1105 struct link_key *key; 1106 u8 type; 1107 1108 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1109 type = HCI_LK_DEBUG_COMBINATION; 1110 else if (hcon->sec_level == BT_SECURITY_FIPS) 1111 type = HCI_LK_AUTH_COMBINATION_P256; 1112 else 1113 type = HCI_LK_UNAUTH_COMBINATION_P256; 1114 1115 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1116 smp->link_key, type, 0, &persistent); 1117 if (key) { 1118 key->link_type = hcon->type; 1119 key->bdaddr_type = hcon->dst_type; 1120 mgmt_new_link_key(hdev, key, persistent); 1121 1122 /* Don't keep debug keys around if the relevant 1123 * flag is not set. 1124 */ 1125 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1126 key->type == HCI_LK_DEBUG_COMBINATION) { 1127 list_del_rcu(&key->list); 1128 kfree_rcu(key, rcu); 1129 } 1130 } 1131 } 1132} 1133 1134static void sc_add_ltk(struct smp_chan *smp) 1135{ 1136 struct hci_conn *hcon = smp->conn->hcon; 1137 u8 key_type, auth; 1138 1139 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1140 key_type = SMP_LTK_P256_DEBUG; 1141 else 1142 key_type = SMP_LTK_P256; 1143 1144 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1145 auth = 1; 1146 else 1147 auth = 0; 1148 1149 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1150 key_type, auth, smp->tk, smp->enc_key_size, 1151 0, 0); 1152} 1153 1154static void sc_generate_link_key(struct smp_chan *smp) 1155{ 1156 /* From core spec. Spells out in ASCII as 'lebr'. */ 1157 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1158 1159 smp->link_key = kzalloc(16, GFP_KERNEL); 1160 if (!smp->link_key) 1161 return; 1162 1163 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1164 /* SALT = 0x000000000000000000000000746D7031 */ 1165 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1166 1167 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1168 kfree_sensitive(smp->link_key); 1169 smp->link_key = NULL; 1170 return; 1171 } 1172 } else { 1173 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1174 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1175 1176 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1177 kfree_sensitive(smp->link_key); 1178 smp->link_key = NULL; 1179 return; 1180 } 1181 } 1182 1183 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1184 kfree_sensitive(smp->link_key); 1185 smp->link_key = NULL; 1186 return; 1187 } 1188} 1189 1190static void smp_allow_key_dist(struct smp_chan *smp) 1191{ 1192 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1193 * will be allowed in each PDU handler to ensure we receive 1194 * them in the correct order. 1195 */ 1196 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1197 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1198 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1199 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1200 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1201 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1202} 1203 1204static void sc_generate_ltk(struct smp_chan *smp) 1205{ 1206 /* From core spec. Spells out in ASCII as 'brle'. */ 1207 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1208 struct hci_conn *hcon = smp->conn->hcon; 1209 struct hci_dev *hdev = hcon->hdev; 1210 struct link_key *key; 1211 1212 key = hci_find_link_key(hdev, &hcon->dst); 1213 if (!key) { 1214 bt_dev_err(hdev, "no Link Key found to generate LTK"); 1215 return; 1216 } 1217 1218 if (key->type == HCI_LK_DEBUG_COMBINATION) 1219 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1220 1221 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1222 /* SALT = 0x000000000000000000000000746D7032 */ 1223 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1224 1225 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1226 return; 1227 } else { 1228 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1229 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1230 1231 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1232 return; 1233 } 1234 1235 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1236 return; 1237 1238 sc_add_ltk(smp); 1239} 1240 1241static void smp_distribute_keys(struct smp_chan *smp) 1242{ 1243 struct smp_cmd_pairing *req, *rsp; 1244 struct l2cap_conn *conn = smp->conn; 1245 struct hci_conn *hcon = conn->hcon; 1246 struct hci_dev *hdev = hcon->hdev; 1247 __u8 *keydist; 1248 1249 bt_dev_dbg(hdev, "conn %p", conn); 1250 1251 rsp = (void *) &smp->prsp[1]; 1252 1253 /* The responder sends its keys first */ 1254 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1255 smp_allow_key_dist(smp); 1256 return; 1257 } 1258 1259 req = (void *) &smp->preq[1]; 1260 1261 if (hcon->out) { 1262 keydist = &rsp->init_key_dist; 1263 *keydist &= req->init_key_dist; 1264 } else { 1265 keydist = &rsp->resp_key_dist; 1266 *keydist &= req->resp_key_dist; 1267 } 1268 1269 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1270 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1271 sc_generate_link_key(smp); 1272 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1273 sc_generate_ltk(smp); 1274 1275 /* Clear the keys which are generated but not distributed */ 1276 *keydist &= ~SMP_SC_NO_DIST; 1277 } 1278 1279 bt_dev_dbg(hdev, "keydist 0x%x", *keydist); 1280 1281 if (*keydist & SMP_DIST_ENC_KEY) { 1282 struct smp_cmd_encrypt_info enc; 1283 struct smp_cmd_initiator_ident ident; 1284 struct smp_ltk *ltk; 1285 u8 authenticated; 1286 __le16 ediv; 1287 __le64 rand; 1288 1289 /* Make sure we generate only the significant amount of 1290 * bytes based on the encryption key size, and set the rest 1291 * of the value to zeroes. 1292 */ 1293 get_random_bytes(enc.ltk, smp->enc_key_size); 1294 memset(enc.ltk + smp->enc_key_size, 0, 1295 sizeof(enc.ltk) - smp->enc_key_size); 1296 1297 get_random_bytes(&ediv, sizeof(ediv)); 1298 get_random_bytes(&rand, sizeof(rand)); 1299 1300 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1301 1302 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1303 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1304 SMP_LTK_RESPONDER, authenticated, enc.ltk, 1305 smp->enc_key_size, ediv, rand); 1306 smp->responder_ltk = ltk; 1307 1308 ident.ediv = ediv; 1309 ident.rand = rand; 1310 1311 smp_send_cmd(conn, SMP_CMD_INITIATOR_IDENT, sizeof(ident), 1312 &ident); 1313 1314 *keydist &= ~SMP_DIST_ENC_KEY; 1315 } 1316 1317 if (*keydist & SMP_DIST_ID_KEY) { 1318 struct smp_cmd_ident_addr_info addrinfo; 1319 struct smp_cmd_ident_info idinfo; 1320 1321 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1322 1323 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1324 1325 /* The hci_conn contains the local identity address 1326 * after the connection has been established. 1327 * 1328 * This is true even when the connection has been 1329 * established using a resolvable random address. 1330 */ 1331 bacpy(&addrinfo.bdaddr, &hcon->src); 1332 addrinfo.addr_type = hcon->src_type; 1333 1334 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1335 &addrinfo); 1336 1337 *keydist &= ~SMP_DIST_ID_KEY; 1338 } 1339 1340 if (*keydist & SMP_DIST_SIGN) { 1341 struct smp_cmd_sign_info sign; 1342 struct smp_csrk *csrk; 1343 1344 /* Generate a new random key */ 1345 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1346 1347 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1348 if (csrk) { 1349 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1350 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1351 else 1352 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1353 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1354 } 1355 smp->responder_csrk = csrk; 1356 1357 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1358 1359 *keydist &= ~SMP_DIST_SIGN; 1360 } 1361 1362 /* If there are still keys to be received wait for them */ 1363 if (smp->remote_key_dist & KEY_DIST_MASK) { 1364 smp_allow_key_dist(smp); 1365 return; 1366 } 1367 1368 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1369 smp_notify_keys(conn); 1370 1371 smp_chan_destroy(conn); 1372} 1373 1374static void smp_timeout(struct work_struct *work) 1375{ 1376 struct smp_chan *smp = container_of(work, struct smp_chan, 1377 security_timer.work); 1378 struct l2cap_conn *conn = smp->conn; 1379 1380 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 1381 1382 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1383} 1384 1385static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1386{ 1387 struct hci_conn *hcon = conn->hcon; 1388 struct l2cap_chan *chan = conn->smp; 1389 struct smp_chan *smp; 1390 1391 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1392 if (!smp) 1393 return NULL; 1394 1395 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1396 if (IS_ERR(smp->tfm_cmac)) { 1397 bt_dev_err(hcon->hdev, "Unable to create CMAC crypto context"); 1398 goto zfree_smp; 1399 } 1400 1401 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 1402 if (IS_ERR(smp->tfm_ecdh)) { 1403 bt_dev_err(hcon->hdev, "Unable to create ECDH crypto context"); 1404 goto free_shash; 1405 } 1406 1407 smp->conn = conn; 1408 chan->data = smp; 1409 1410 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1411 1412 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1413 1414 hci_conn_hold(hcon); 1415 1416 return smp; 1417 1418free_shash: 1419 crypto_free_shash(smp->tfm_cmac); 1420zfree_smp: 1421 kfree_sensitive(smp); 1422 return NULL; 1423} 1424 1425static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1426{ 1427 struct hci_conn *hcon = smp->conn->hcon; 1428 u8 *na, *nb, a[7], b[7]; 1429 1430 if (hcon->out) { 1431 na = smp->prnd; 1432 nb = smp->rrnd; 1433 } else { 1434 na = smp->rrnd; 1435 nb = smp->prnd; 1436 } 1437 1438 memcpy(a, &hcon->init_addr, 6); 1439 memcpy(b, &hcon->resp_addr, 6); 1440 a[6] = hcon->init_addr_type; 1441 b[6] = hcon->resp_addr_type; 1442 1443 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1444} 1445 1446static void sc_dhkey_check(struct smp_chan *smp) 1447{ 1448 struct hci_conn *hcon = smp->conn->hcon; 1449 struct smp_cmd_dhkey_check check; 1450 u8 a[7], b[7], *local_addr, *remote_addr; 1451 u8 io_cap[3], r[16]; 1452 1453 memcpy(a, &hcon->init_addr, 6); 1454 memcpy(b, &hcon->resp_addr, 6); 1455 a[6] = hcon->init_addr_type; 1456 b[6] = hcon->resp_addr_type; 1457 1458 if (hcon->out) { 1459 local_addr = a; 1460 remote_addr = b; 1461 memcpy(io_cap, &smp->preq[1], 3); 1462 } else { 1463 local_addr = b; 1464 remote_addr = a; 1465 memcpy(io_cap, &smp->prsp[1], 3); 1466 } 1467 1468 memset(r, 0, sizeof(r)); 1469 1470 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1471 put_unaligned_le32(hcon->passkey_notify, r); 1472 1473 if (smp->method == REQ_OOB) 1474 memcpy(r, smp->rr, 16); 1475 1476 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1477 local_addr, remote_addr, check.e); 1478 1479 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1480} 1481 1482static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1483{ 1484 struct l2cap_conn *conn = smp->conn; 1485 struct hci_conn *hcon = conn->hcon; 1486 struct smp_cmd_pairing_confirm cfm; 1487 u8 r; 1488 1489 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1490 r |= 0x80; 1491 1492 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1493 1494 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1495 cfm.confirm_val)) 1496 return SMP_UNSPECIFIED; 1497 1498 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1499 1500 return 0; 1501} 1502 1503static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1504{ 1505 struct l2cap_conn *conn = smp->conn; 1506 struct hci_conn *hcon = conn->hcon; 1507 struct hci_dev *hdev = hcon->hdev; 1508 u8 cfm[16], r; 1509 1510 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1511 if (smp->passkey_round >= 20) 1512 return 0; 1513 1514 switch (smp_op) { 1515 case SMP_CMD_PAIRING_RANDOM: 1516 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1517 r |= 0x80; 1518 1519 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1520 smp->rrnd, r, cfm)) 1521 return SMP_UNSPECIFIED; 1522 1523 if (crypto_memneq(smp->pcnf, cfm, 16)) 1524 return SMP_CONFIRM_FAILED; 1525 1526 smp->passkey_round++; 1527 1528 if (smp->passkey_round == 20) { 1529 /* Generate MacKey and LTK */ 1530 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1531 return SMP_UNSPECIFIED; 1532 } 1533 1534 /* The round is only complete when the initiator 1535 * receives pairing random. 1536 */ 1537 if (!hcon->out) { 1538 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1539 sizeof(smp->prnd), smp->prnd); 1540 if (smp->passkey_round == 20) 1541 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1542 else 1543 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1544 return 0; 1545 } 1546 1547 /* Start the next round */ 1548 if (smp->passkey_round != 20) 1549 return sc_passkey_round(smp, 0); 1550 1551 /* Passkey rounds are complete - start DHKey Check */ 1552 sc_dhkey_check(smp); 1553 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1554 1555 break; 1556 1557 case SMP_CMD_PAIRING_CONFIRM: 1558 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1559 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1560 return 0; 1561 } 1562 1563 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1564 1565 if (hcon->out) { 1566 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1567 sizeof(smp->prnd), smp->prnd); 1568 return 0; 1569 } 1570 1571 return sc_passkey_send_confirm(smp); 1572 1573 case SMP_CMD_PUBLIC_KEY: 1574 default: 1575 /* Initiating device starts the round */ 1576 if (!hcon->out) 1577 return 0; 1578 1579 bt_dev_dbg(hdev, "Starting passkey round %u", 1580 smp->passkey_round + 1); 1581 1582 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1583 1584 return sc_passkey_send_confirm(smp); 1585 } 1586 1587 return 0; 1588} 1589 1590static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1591{ 1592 struct l2cap_conn *conn = smp->conn; 1593 struct hci_conn *hcon = conn->hcon; 1594 u8 smp_op; 1595 1596 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1597 1598 switch (mgmt_op) { 1599 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1600 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1601 return 0; 1602 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1603 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1604 return 0; 1605 case MGMT_OP_USER_PASSKEY_REPLY: 1606 hcon->passkey_notify = le32_to_cpu(passkey); 1607 smp->passkey_round = 0; 1608 1609 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1610 smp_op = SMP_CMD_PAIRING_CONFIRM; 1611 else 1612 smp_op = 0; 1613 1614 if (sc_passkey_round(smp, smp_op)) 1615 return -EIO; 1616 1617 return 0; 1618 } 1619 1620 /* Initiator sends DHKey check first */ 1621 if (hcon->out) { 1622 sc_dhkey_check(smp); 1623 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1624 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1625 sc_dhkey_check(smp); 1626 sc_add_ltk(smp); 1627 } 1628 1629 return 0; 1630} 1631 1632int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1633{ 1634 struct l2cap_conn *conn = hcon->l2cap_data; 1635 struct l2cap_chan *chan; 1636 struct smp_chan *smp; 1637 u32 value; 1638 int err; 1639 1640 bt_dev_dbg(conn->hcon->hdev, ""); 1641 1642 if (!conn) 1643 return -ENOTCONN; 1644 1645 chan = conn->smp; 1646 if (!chan) 1647 return -ENOTCONN; 1648 1649 l2cap_chan_lock(chan); 1650 if (!chan->data) { 1651 err = -ENOTCONN; 1652 goto unlock; 1653 } 1654 1655 smp = chan->data; 1656 1657 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1658 err = sc_user_reply(smp, mgmt_op, passkey); 1659 goto unlock; 1660 } 1661 1662 switch (mgmt_op) { 1663 case MGMT_OP_USER_PASSKEY_REPLY: 1664 value = le32_to_cpu(passkey); 1665 memset(smp->tk, 0, sizeof(smp->tk)); 1666 bt_dev_dbg(conn->hcon->hdev, "PassKey: %d", value); 1667 put_unaligned_le32(value, smp->tk); 1668 fallthrough; 1669 case MGMT_OP_USER_CONFIRM_REPLY: 1670 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1671 break; 1672 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1673 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1674 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1675 err = 0; 1676 goto unlock; 1677 default: 1678 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1679 err = -EOPNOTSUPP; 1680 goto unlock; 1681 } 1682 1683 err = 0; 1684 1685 /* If it is our turn to send Pairing Confirm, do so now */ 1686 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1687 u8 rsp = smp_confirm(smp); 1688 if (rsp) 1689 smp_failure(conn, rsp); 1690 } 1691 1692unlock: 1693 l2cap_chan_unlock(chan); 1694 return err; 1695} 1696 1697static void build_bredr_pairing_cmd(struct smp_chan *smp, 1698 struct smp_cmd_pairing *req, 1699 struct smp_cmd_pairing *rsp) 1700{ 1701 struct l2cap_conn *conn = smp->conn; 1702 struct hci_dev *hdev = conn->hcon->hdev; 1703 u8 local_dist = 0, remote_dist = 0; 1704 1705 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1706 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1707 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1708 } 1709 1710 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1711 remote_dist |= SMP_DIST_ID_KEY; 1712 1713 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1714 local_dist |= SMP_DIST_ID_KEY; 1715 1716 if (!rsp) { 1717 memset(req, 0, sizeof(*req)); 1718 1719 req->auth_req = SMP_AUTH_CT2; 1720 req->init_key_dist = local_dist; 1721 req->resp_key_dist = remote_dist; 1722 req->max_key_size = conn->hcon->enc_key_size; 1723 1724 smp->remote_key_dist = remote_dist; 1725 1726 return; 1727 } 1728 1729 memset(rsp, 0, sizeof(*rsp)); 1730 1731 rsp->auth_req = SMP_AUTH_CT2; 1732 rsp->max_key_size = conn->hcon->enc_key_size; 1733 rsp->init_key_dist = req->init_key_dist & remote_dist; 1734 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1735 1736 smp->remote_key_dist = rsp->init_key_dist; 1737} 1738 1739static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1740{ 1741 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1742 struct l2cap_chan *chan = conn->smp; 1743 struct hci_dev *hdev = conn->hcon->hdev; 1744 struct smp_chan *smp; 1745 u8 key_size, auth, sec_level; 1746 int ret; 1747 1748 bt_dev_dbg(hdev, "conn %p", conn); 1749 1750 if (skb->len < sizeof(*req)) 1751 return SMP_INVALID_PARAMS; 1752 1753 if (conn->hcon->role != HCI_ROLE_SLAVE) 1754 return SMP_CMD_NOTSUPP; 1755 1756 if (!chan->data) 1757 smp = smp_chan_create(conn); 1758 else 1759 smp = chan->data; 1760 1761 if (!smp) 1762 return SMP_UNSPECIFIED; 1763 1764 /* We didn't start the pairing, so match remote */ 1765 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1766 1767 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1768 (auth & SMP_AUTH_BONDING)) 1769 return SMP_PAIRING_NOTSUPP; 1770 1771 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1772 return SMP_AUTH_REQUIREMENTS; 1773 1774 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1775 memcpy(&smp->preq[1], req, sizeof(*req)); 1776 skb_pull(skb, sizeof(*req)); 1777 1778 /* If the remote side's OOB flag is set it means it has 1779 * successfully received our local OOB data - therefore set the 1780 * flag to indicate that local OOB is in use. 1781 */ 1782 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1783 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1784 1785 /* SMP over BR/EDR requires special treatment */ 1786 if (conn->hcon->type == ACL_LINK) { 1787 /* We must have a BR/EDR SC link */ 1788 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1789 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1790 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1791 1792 set_bit(SMP_FLAG_SC, &smp->flags); 1793 1794 build_bredr_pairing_cmd(smp, req, &rsp); 1795 1796 if (req->auth_req & SMP_AUTH_CT2) 1797 set_bit(SMP_FLAG_CT2, &smp->flags); 1798 1799 key_size = min(req->max_key_size, rsp.max_key_size); 1800 if (check_enc_key_size(conn, key_size)) 1801 return SMP_ENC_KEY_SIZE; 1802 1803 /* Clear bits which are generated but not distributed */ 1804 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1805 1806 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1807 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1808 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1809 1810 smp_distribute_keys(smp); 1811 return 0; 1812 } 1813 1814 build_pairing_cmd(conn, req, &rsp, auth); 1815 1816 if (rsp.auth_req & SMP_AUTH_SC) { 1817 set_bit(SMP_FLAG_SC, &smp->flags); 1818 1819 if (rsp.auth_req & SMP_AUTH_CT2) 1820 set_bit(SMP_FLAG_CT2, &smp->flags); 1821 } 1822 1823 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1824 sec_level = BT_SECURITY_MEDIUM; 1825 else 1826 sec_level = authreq_to_seclevel(auth); 1827 1828 if (sec_level > conn->hcon->pending_sec_level) 1829 conn->hcon->pending_sec_level = sec_level; 1830 1831 /* If we need MITM check that it can be achieved */ 1832 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1833 u8 method; 1834 1835 method = get_auth_method(smp, conn->hcon->io_capability, 1836 req->io_capability); 1837 if (method == JUST_WORKS || method == JUST_CFM) 1838 return SMP_AUTH_REQUIREMENTS; 1839 } 1840 1841 key_size = min(req->max_key_size, rsp.max_key_size); 1842 if (check_enc_key_size(conn, key_size)) 1843 return SMP_ENC_KEY_SIZE; 1844 1845 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1846 1847 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1848 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1849 1850 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1851 1852 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1853 1854 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1855 * SC case, however some implementations incorrectly copy RFU auth 1856 * req bits from our security request, which may create a false 1857 * positive SC enablement. 1858 */ 1859 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1860 1861 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1862 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1863 /* Clear bits which are generated but not distributed */ 1864 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1865 /* Wait for Public Key from Initiating Device */ 1866 return 0; 1867 } 1868 1869 /* Request setup of TK */ 1870 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1871 if (ret) 1872 return SMP_UNSPECIFIED; 1873 1874 return 0; 1875} 1876 1877static u8 sc_send_public_key(struct smp_chan *smp) 1878{ 1879 struct hci_dev *hdev = smp->conn->hcon->hdev; 1880 1881 bt_dev_dbg(hdev, ""); 1882 1883 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1884 struct l2cap_chan *chan = hdev->smp_data; 1885 struct smp_dev *smp_dev; 1886 1887 if (!chan || !chan->data) 1888 return SMP_UNSPECIFIED; 1889 1890 smp_dev = chan->data; 1891 1892 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1893 memcpy(smp->lr, smp_dev->local_rand, 16); 1894 1895 if (smp_dev->debug_key) 1896 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1897 1898 goto done; 1899 } 1900 1901 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1902 bt_dev_dbg(hdev, "Using debug keys"); 1903 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk)) 1904 return SMP_UNSPECIFIED; 1905 memcpy(smp->local_pk, debug_pk, 64); 1906 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1907 } else { 1908 while (true) { 1909 /* Generate key pair for Secure Connections */ 1910 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk)) 1911 return SMP_UNSPECIFIED; 1912 1913 /* This is unlikely, but we need to check that 1914 * we didn't accidentially generate a debug key. 1915 */ 1916 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 1917 break; 1918 } 1919 } 1920 1921done: 1922 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1923 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1924 1925 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1926 1927 return 0; 1928} 1929 1930static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1931{ 1932 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1933 struct l2cap_chan *chan = conn->smp; 1934 struct smp_chan *smp = chan->data; 1935 struct hci_dev *hdev = conn->hcon->hdev; 1936 u8 key_size, auth; 1937 int ret; 1938 1939 bt_dev_dbg(hdev, "conn %p", conn); 1940 1941 if (skb->len < sizeof(*rsp)) 1942 return SMP_INVALID_PARAMS; 1943 1944 if (conn->hcon->role != HCI_ROLE_MASTER) 1945 return SMP_CMD_NOTSUPP; 1946 1947 skb_pull(skb, sizeof(*rsp)); 1948 1949 req = (void *) &smp->preq[1]; 1950 1951 key_size = min(req->max_key_size, rsp->max_key_size); 1952 if (check_enc_key_size(conn, key_size)) 1953 return SMP_ENC_KEY_SIZE; 1954 1955 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1956 1957 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1958 return SMP_AUTH_REQUIREMENTS; 1959 1960 /* If the remote side's OOB flag is set it means it has 1961 * successfully received our local OOB data - therefore set the 1962 * flag to indicate that local OOB is in use. 1963 */ 1964 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1965 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1966 1967 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1968 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1969 1970 /* Update remote key distribution in case the remote cleared 1971 * some bits that we had enabled in our request. 1972 */ 1973 smp->remote_key_dist &= rsp->resp_key_dist; 1974 1975 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1976 set_bit(SMP_FLAG_CT2, &smp->flags); 1977 1978 /* For BR/EDR this means we're done and can start phase 3 */ 1979 if (conn->hcon->type == ACL_LINK) { 1980 /* Clear bits which are generated but not distributed */ 1981 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1982 smp_distribute_keys(smp); 1983 return 0; 1984 } 1985 1986 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1987 set_bit(SMP_FLAG_SC, &smp->flags); 1988 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1989 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1990 1991 /* If we need MITM check that it can be achieved */ 1992 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1993 u8 method; 1994 1995 method = get_auth_method(smp, req->io_capability, 1996 rsp->io_capability); 1997 if (method == JUST_WORKS || method == JUST_CFM) 1998 return SMP_AUTH_REQUIREMENTS; 1999 } 2000 2001 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 2002 2003 /* Update remote key distribution in case the remote cleared 2004 * some bits that we had enabled in our request. 2005 */ 2006 smp->remote_key_dist &= rsp->resp_key_dist; 2007 2008 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2009 /* Clear bits which are generated but not distributed */ 2010 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 2011 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 2012 return sc_send_public_key(smp); 2013 } 2014 2015 auth |= req->auth_req; 2016 2017 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2018 if (ret) 2019 return SMP_UNSPECIFIED; 2020 2021 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2022 2023 /* Can't compose response until we have been confirmed */ 2024 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2025 return smp_confirm(smp); 2026 2027 return 0; 2028} 2029 2030static u8 sc_check_confirm(struct smp_chan *smp) 2031{ 2032 struct l2cap_conn *conn = smp->conn; 2033 2034 bt_dev_dbg(conn->hcon->hdev, ""); 2035 2036 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2037 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2038 2039 if (conn->hcon->out) { 2040 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2041 smp->prnd); 2042 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2043 } 2044 2045 return 0; 2046} 2047 2048/* Work-around for some implementations that incorrectly copy RFU bits 2049 * from our security request and thereby create the impression that 2050 * we're doing SC when in fact the remote doesn't support it. 2051 */ 2052static int fixup_sc_false_positive(struct smp_chan *smp) 2053{ 2054 struct l2cap_conn *conn = smp->conn; 2055 struct hci_conn *hcon = conn->hcon; 2056 struct hci_dev *hdev = hcon->hdev; 2057 struct smp_cmd_pairing *req, *rsp; 2058 u8 auth; 2059 2060 /* The issue is only observed when we're in responder role */ 2061 if (hcon->out) 2062 return SMP_UNSPECIFIED; 2063 2064 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2065 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode"); 2066 return SMP_UNSPECIFIED; 2067 } 2068 2069 bt_dev_err(hdev, "trying to fall back to legacy SMP"); 2070 2071 req = (void *) &smp->preq[1]; 2072 rsp = (void *) &smp->prsp[1]; 2073 2074 /* Rebuild key dist flags which may have been cleared for SC */ 2075 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2076 2077 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2078 2079 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2080 bt_dev_err(hdev, "failed to fall back to legacy SMP"); 2081 return SMP_UNSPECIFIED; 2082 } 2083 2084 clear_bit(SMP_FLAG_SC, &smp->flags); 2085 2086 return 0; 2087} 2088 2089static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2090{ 2091 struct l2cap_chan *chan = conn->smp; 2092 struct smp_chan *smp = chan->data; 2093 struct hci_conn *hcon = conn->hcon; 2094 struct hci_dev *hdev = hcon->hdev; 2095 2096 bt_dev_dbg(hdev, "conn %p %s", conn, 2097 hcon->out ? "initiator" : "responder"); 2098 2099 if (skb->len < sizeof(smp->pcnf)) 2100 return SMP_INVALID_PARAMS; 2101 2102 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2103 skb_pull(skb, sizeof(smp->pcnf)); 2104 2105 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2106 int ret; 2107 2108 /* Public Key exchange must happen before any other steps */ 2109 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2110 return sc_check_confirm(smp); 2111 2112 bt_dev_err(hdev, "Unexpected SMP Pairing Confirm"); 2113 2114 ret = fixup_sc_false_positive(smp); 2115 if (ret) 2116 return ret; 2117 } 2118 2119 if (conn->hcon->out) { 2120 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2121 smp->prnd); 2122 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2123 return 0; 2124 } 2125 2126 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2127 return smp_confirm(smp); 2128 2129 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2130 2131 return 0; 2132} 2133 2134static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2135{ 2136 struct l2cap_chan *chan = conn->smp; 2137 struct smp_chan *smp = chan->data; 2138 struct hci_conn *hcon = conn->hcon; 2139 u8 *pkax, *pkbx, *na, *nb, confirm_hint; 2140 u32 passkey; 2141 int err; 2142 2143 bt_dev_dbg(hcon->hdev, "conn %p", conn); 2144 2145 if (skb->len < sizeof(smp->rrnd)) 2146 return SMP_INVALID_PARAMS; 2147 2148 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2149 skb_pull(skb, sizeof(smp->rrnd)); 2150 2151 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2152 return smp_random(smp); 2153 2154 if (hcon->out) { 2155 pkax = smp->local_pk; 2156 pkbx = smp->remote_pk; 2157 na = smp->prnd; 2158 nb = smp->rrnd; 2159 } else { 2160 pkax = smp->remote_pk; 2161 pkbx = smp->local_pk; 2162 na = smp->rrnd; 2163 nb = smp->prnd; 2164 } 2165 2166 if (smp->method == REQ_OOB) { 2167 if (!hcon->out) 2168 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2169 sizeof(smp->prnd), smp->prnd); 2170 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2171 goto mackey_and_ltk; 2172 } 2173 2174 /* Passkey entry has special treatment */ 2175 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2176 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2177 2178 if (hcon->out) { 2179 u8 cfm[16]; 2180 2181 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2182 smp->rrnd, 0, cfm); 2183 if (err) 2184 return SMP_UNSPECIFIED; 2185 2186 if (crypto_memneq(smp->pcnf, cfm, 16)) 2187 return SMP_CONFIRM_FAILED; 2188 } else { 2189 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2190 smp->prnd); 2191 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2192 2193 /* Only Just-Works pairing requires extra checks */ 2194 if (smp->method != JUST_WORKS) 2195 goto mackey_and_ltk; 2196 2197 /* If there already exists long term key in local host, leave 2198 * the decision to user space since the remote device could 2199 * be legitimate or malicious. 2200 */ 2201 if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 2202 hcon->role)) { 2203 /* Set passkey to 0. The value can be any number since 2204 * it'll be ignored anyway. 2205 */ 2206 passkey = 0; 2207 confirm_hint = 1; 2208 goto confirm; 2209 } 2210 } 2211 2212mackey_and_ltk: 2213 /* Generate MacKey and LTK */ 2214 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); 2215 if (err) 2216 return SMP_UNSPECIFIED; 2217 2218 if (smp->method == REQ_OOB) { 2219 if (hcon->out) { 2220 sc_dhkey_check(smp); 2221 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2222 } 2223 return 0; 2224 } 2225 2226 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); 2227 if (err) 2228 return SMP_UNSPECIFIED; 2229 2230 confirm_hint = 0; 2231 2232confirm: 2233 if (smp->method == JUST_WORKS) 2234 confirm_hint = 1; 2235 2236 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2237 hcon->dst_type, passkey, confirm_hint); 2238 if (err) 2239 return SMP_UNSPECIFIED; 2240 2241 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2242 2243 return 0; 2244} 2245 2246static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2247{ 2248 struct smp_ltk *key; 2249 struct hci_conn *hcon = conn->hcon; 2250 2251 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2252 if (!key) 2253 return false; 2254 2255 if (smp_ltk_sec_level(key) < sec_level) 2256 return false; 2257 2258 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2259 return true; 2260 2261 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2262 hcon->enc_key_size = key->enc_size; 2263 2264 /* We never store STKs for initiator role, so clear this flag */ 2265 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2266 2267 return true; 2268} 2269 2270bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2271 enum smp_key_pref key_pref) 2272{ 2273 if (sec_level == BT_SECURITY_LOW) 2274 return true; 2275 2276 /* If we're encrypted with an STK but the caller prefers using 2277 * LTK claim insufficient security. This way we allow the 2278 * connection to be re-encrypted with an LTK, even if the LTK 2279 * provides the same level of security. Only exception is if we 2280 * don't have an LTK (e.g. because of key distribution bits). 2281 */ 2282 if (key_pref == SMP_USE_LTK && 2283 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2284 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2285 return false; 2286 2287 if (hcon->sec_level >= sec_level) 2288 return true; 2289 2290 return false; 2291} 2292 2293static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2294{ 2295 struct smp_cmd_security_req *rp = (void *) skb->data; 2296 struct smp_cmd_pairing cp; 2297 struct hci_conn *hcon = conn->hcon; 2298 struct hci_dev *hdev = hcon->hdev; 2299 struct smp_chan *smp; 2300 u8 sec_level, auth; 2301 2302 bt_dev_dbg(hdev, "conn %p", conn); 2303 2304 if (skb->len < sizeof(*rp)) 2305 return SMP_INVALID_PARAMS; 2306 2307 if (hcon->role != HCI_ROLE_MASTER) 2308 return SMP_CMD_NOTSUPP; 2309 2310 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2311 2312 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2313 return SMP_AUTH_REQUIREMENTS; 2314 2315 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2316 sec_level = BT_SECURITY_MEDIUM; 2317 else 2318 sec_level = authreq_to_seclevel(auth); 2319 2320 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) { 2321 /* If link is already encrypted with sufficient security we 2322 * still need refresh encryption as per Core Spec 5.0 Vol 3, 2323 * Part H 2.4.6 2324 */ 2325 smp_ltk_encrypt(conn, hcon->sec_level); 2326 return 0; 2327 } 2328 2329 if (sec_level > hcon->pending_sec_level) 2330 hcon->pending_sec_level = sec_level; 2331 2332 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2333 return 0; 2334 2335 smp = smp_chan_create(conn); 2336 if (!smp) 2337 return SMP_UNSPECIFIED; 2338 2339 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2340 (auth & SMP_AUTH_BONDING)) 2341 return SMP_PAIRING_NOTSUPP; 2342 2343 skb_pull(skb, sizeof(*rp)); 2344 2345 memset(&cp, 0, sizeof(cp)); 2346 build_pairing_cmd(conn, &cp, NULL, auth); 2347 2348 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2349 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2350 2351 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2352 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2353 2354 return 0; 2355} 2356 2357int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2358{ 2359 struct l2cap_conn *conn = hcon->l2cap_data; 2360 struct l2cap_chan *chan; 2361 struct smp_chan *smp; 2362 __u8 authreq; 2363 int ret; 2364 2365 bt_dev_dbg(hcon->hdev, "conn %p hcon %p level 0x%2.2x", conn, hcon, 2366 sec_level); 2367 2368 /* This may be NULL if there's an unexpected disconnection */ 2369 if (!conn) 2370 return 1; 2371 2372 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2373 return 1; 2374 2375 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2376 return 1; 2377 2378 if (sec_level > hcon->pending_sec_level) 2379 hcon->pending_sec_level = sec_level; 2380 2381 if (hcon->role == HCI_ROLE_MASTER) 2382 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2383 return 0; 2384 2385 chan = conn->smp; 2386 if (!chan) { 2387 bt_dev_err(hcon->hdev, "security requested but not available"); 2388 return 1; 2389 } 2390 2391 l2cap_chan_lock(chan); 2392 2393 /* If SMP is already in progress ignore this request */ 2394 if (chan->data) { 2395 ret = 0; 2396 goto unlock; 2397 } 2398 2399 smp = smp_chan_create(conn); 2400 if (!smp) { 2401 ret = 1; 2402 goto unlock; 2403 } 2404 2405 authreq = seclevel_to_authreq(sec_level); 2406 2407 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2408 authreq |= SMP_AUTH_SC; 2409 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2410 authreq |= SMP_AUTH_CT2; 2411 } 2412 2413 /* Don't attempt to set MITM if setting is overridden by debugfs 2414 * Needed to pass certification test SM/MAS/PKE/BV-01-C 2415 */ 2416 if (!hci_dev_test_flag(hcon->hdev, HCI_FORCE_NO_MITM)) { 2417 /* Require MITM if IO Capability allows or the security level 2418 * requires it. 2419 */ 2420 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2421 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2422 authreq |= SMP_AUTH_MITM; 2423 } 2424 2425 if (hcon->role == HCI_ROLE_MASTER) { 2426 struct smp_cmd_pairing cp; 2427 2428 build_pairing_cmd(conn, &cp, NULL, authreq); 2429 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2430 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2431 2432 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2433 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2434 } else { 2435 struct smp_cmd_security_req cp; 2436 cp.auth_req = authreq; 2437 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2438 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2439 } 2440 2441 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2442 ret = 0; 2443 2444unlock: 2445 l2cap_chan_unlock(chan); 2446 return ret; 2447} 2448 2449int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr, 2450 u8 addr_type) 2451{ 2452 struct hci_conn *hcon; 2453 struct l2cap_conn *conn; 2454 struct l2cap_chan *chan; 2455 struct smp_chan *smp; 2456 int err; 2457 2458 err = hci_remove_ltk(hdev, bdaddr, addr_type); 2459 hci_remove_irk(hdev, bdaddr, addr_type); 2460 2461 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type); 2462 if (!hcon) 2463 goto done; 2464 2465 conn = hcon->l2cap_data; 2466 if (!conn) 2467 goto done; 2468 2469 chan = conn->smp; 2470 if (!chan) 2471 goto done; 2472 2473 l2cap_chan_lock(chan); 2474 2475 smp = chan->data; 2476 if (smp) { 2477 /* Set keys to NULL to make sure smp_failure() does not try to 2478 * remove and free already invalidated rcu list entries. */ 2479 smp->ltk = NULL; 2480 smp->responder_ltk = NULL; 2481 smp->remote_irk = NULL; 2482 2483 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2484 smp_failure(conn, 0); 2485 else 2486 smp_failure(conn, SMP_UNSPECIFIED); 2487 err = 0; 2488 } 2489 2490 l2cap_chan_unlock(chan); 2491 2492done: 2493 return err; 2494} 2495 2496static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2497{ 2498 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2499 struct l2cap_chan *chan = conn->smp; 2500 struct smp_chan *smp = chan->data; 2501 2502 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 2503 2504 if (skb->len < sizeof(*rp)) 2505 return SMP_INVALID_PARAMS; 2506 2507 /* Pairing is aborted if any blocked keys are distributed */ 2508 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK, 2509 rp->ltk)) { 2510 bt_dev_warn_ratelimited(conn->hcon->hdev, 2511 "LTK blocked for %pMR", 2512 &conn->hcon->dst); 2513 return SMP_INVALID_PARAMS; 2514 } 2515 2516 SMP_ALLOW_CMD(smp, SMP_CMD_INITIATOR_IDENT); 2517 2518 skb_pull(skb, sizeof(*rp)); 2519 2520 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2521 2522 return 0; 2523} 2524 2525static int smp_cmd_initiator_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2526{ 2527 struct smp_cmd_initiator_ident *rp = (void *)skb->data; 2528 struct l2cap_chan *chan = conn->smp; 2529 struct smp_chan *smp = chan->data; 2530 struct hci_dev *hdev = conn->hcon->hdev; 2531 struct hci_conn *hcon = conn->hcon; 2532 struct smp_ltk *ltk; 2533 u8 authenticated; 2534 2535 bt_dev_dbg(hdev, "conn %p", conn); 2536 2537 if (skb->len < sizeof(*rp)) 2538 return SMP_INVALID_PARAMS; 2539 2540 /* Mark the information as received */ 2541 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2542 2543 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2544 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2545 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2546 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2547 2548 skb_pull(skb, sizeof(*rp)); 2549 2550 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2551 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2552 authenticated, smp->tk, smp->enc_key_size, 2553 rp->ediv, rp->rand); 2554 smp->ltk = ltk; 2555 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2556 smp_distribute_keys(smp); 2557 2558 return 0; 2559} 2560 2561static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2562{ 2563 struct smp_cmd_ident_info *info = (void *) skb->data; 2564 struct l2cap_chan *chan = conn->smp; 2565 struct smp_chan *smp = chan->data; 2566 2567 bt_dev_dbg(conn->hcon->hdev, ""); 2568 2569 if (skb->len < sizeof(*info)) 2570 return SMP_INVALID_PARAMS; 2571 2572 /* Pairing is aborted if any blocked keys are distributed */ 2573 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK, 2574 info->irk)) { 2575 bt_dev_warn_ratelimited(conn->hcon->hdev, 2576 "Identity key blocked for %pMR", 2577 &conn->hcon->dst); 2578 return SMP_INVALID_PARAMS; 2579 } 2580 2581 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2582 2583 skb_pull(skb, sizeof(*info)); 2584 2585 memcpy(smp->irk, info->irk, 16); 2586 2587 return 0; 2588} 2589 2590static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2591 struct sk_buff *skb) 2592{ 2593 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2594 struct l2cap_chan *chan = conn->smp; 2595 struct smp_chan *smp = chan->data; 2596 struct hci_conn *hcon = conn->hcon; 2597 bdaddr_t rpa; 2598 2599 bt_dev_dbg(hcon->hdev, ""); 2600 2601 if (skb->len < sizeof(*info)) 2602 return SMP_INVALID_PARAMS; 2603 2604 /* Mark the information as received */ 2605 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2606 2607 if (smp->remote_key_dist & SMP_DIST_SIGN) 2608 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2609 2610 skb_pull(skb, sizeof(*info)); 2611 2612 /* Strictly speaking the Core Specification (4.1) allows sending 2613 * an empty address which would force us to rely on just the IRK 2614 * as "identity information". However, since such 2615 * implementations are not known of and in order to not over 2616 * complicate our implementation, simply pretend that we never 2617 * received an IRK for such a device. 2618 * 2619 * The Identity Address must also be a Static Random or Public 2620 * Address, which hci_is_identity_address() checks for. 2621 */ 2622 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2623 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2624 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address"); 2625 goto distribute; 2626 } 2627 2628 /* Drop IRK if peer is using identity address during pairing but is 2629 * providing different address as identity information. 2630 * 2631 * Microsoft Surface Precision Mouse is known to have this bug. 2632 */ 2633 if (hci_is_identity_address(&hcon->dst, hcon->dst_type) && 2634 (bacmp(&info->bdaddr, &hcon->dst) || 2635 info->addr_type != hcon->dst_type)) { 2636 bt_dev_err(hcon->hdev, 2637 "ignoring IRK with invalid identity address"); 2638 goto distribute; 2639 } 2640 2641 bacpy(&smp->id_addr, &info->bdaddr); 2642 smp->id_addr_type = info->addr_type; 2643 2644 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2645 bacpy(&rpa, &hcon->dst); 2646 else 2647 bacpy(&rpa, BDADDR_ANY); 2648 2649 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2650 smp->id_addr_type, smp->irk, &rpa); 2651 2652distribute: 2653 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2654 smp_distribute_keys(smp); 2655 2656 return 0; 2657} 2658 2659static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2660{ 2661 struct smp_cmd_sign_info *rp = (void *) skb->data; 2662 struct l2cap_chan *chan = conn->smp; 2663 struct smp_chan *smp = chan->data; 2664 struct smp_csrk *csrk; 2665 2666 bt_dev_dbg(conn->hcon->hdev, "conn %p", conn); 2667 2668 if (skb->len < sizeof(*rp)) 2669 return SMP_INVALID_PARAMS; 2670 2671 /* Mark the information as received */ 2672 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2673 2674 skb_pull(skb, sizeof(*rp)); 2675 2676 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2677 if (csrk) { 2678 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2679 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2680 else 2681 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2682 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2683 } 2684 smp->csrk = csrk; 2685 smp_distribute_keys(smp); 2686 2687 return 0; 2688} 2689 2690static u8 sc_select_method(struct smp_chan *smp) 2691{ 2692 struct l2cap_conn *conn = smp->conn; 2693 struct hci_conn *hcon = conn->hcon; 2694 struct smp_cmd_pairing *local, *remote; 2695 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2696 2697 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2698 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2699 return REQ_OOB; 2700 2701 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2702 * which are needed as inputs to some crypto functions. To get 2703 * the "struct smp_cmd_pairing" from them we need to skip the 2704 * first byte which contains the opcode. 2705 */ 2706 if (hcon->out) { 2707 local = (void *) &smp->preq[1]; 2708 remote = (void *) &smp->prsp[1]; 2709 } else { 2710 local = (void *) &smp->prsp[1]; 2711 remote = (void *) &smp->preq[1]; 2712 } 2713 2714 local_io = local->io_capability; 2715 remote_io = remote->io_capability; 2716 2717 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2718 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2719 2720 /* If either side wants MITM, look up the method from the table, 2721 * otherwise use JUST WORKS. 2722 */ 2723 if (local_mitm || remote_mitm) 2724 method = get_auth_method(smp, local_io, remote_io); 2725 else 2726 method = JUST_WORKS; 2727 2728 /* Don't confirm locally initiated pairing attempts */ 2729 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2730 method = JUST_WORKS; 2731 2732 return method; 2733} 2734 2735static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2736{ 2737 struct smp_cmd_public_key *key = (void *) skb->data; 2738 struct hci_conn *hcon = conn->hcon; 2739 struct l2cap_chan *chan = conn->smp; 2740 struct smp_chan *smp = chan->data; 2741 struct hci_dev *hdev = hcon->hdev; 2742 struct crypto_kpp *tfm_ecdh; 2743 struct smp_cmd_pairing_confirm cfm; 2744 int err; 2745 2746 bt_dev_dbg(hdev, "conn %p", conn); 2747 2748 if (skb->len < sizeof(*key)) 2749 return SMP_INVALID_PARAMS; 2750 2751 /* Check if remote and local public keys are the same and debug key is 2752 * not in use. 2753 */ 2754 if (!test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags) && 2755 !crypto_memneq(key, smp->local_pk, 64)) { 2756 bt_dev_err(hdev, "Remote and local public keys are identical"); 2757 return SMP_UNSPECIFIED; 2758 } 2759 2760 memcpy(smp->remote_pk, key, 64); 2761 2762 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2763 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2764 smp->rr, 0, cfm.confirm_val); 2765 if (err) 2766 return SMP_UNSPECIFIED; 2767 2768 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16)) 2769 return SMP_CONFIRM_FAILED; 2770 } 2771 2772 /* Non-initiating device sends its public key after receiving 2773 * the key from the initiating device. 2774 */ 2775 if (!hcon->out) { 2776 err = sc_send_public_key(smp); 2777 if (err) 2778 return err; 2779 } 2780 2781 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2782 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2783 2784 /* Compute the shared secret on the same crypto tfm on which the private 2785 * key was set/generated. 2786 */ 2787 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 2788 struct l2cap_chan *hchan = hdev->smp_data; 2789 struct smp_dev *smp_dev; 2790 2791 if (!hchan || !hchan->data) 2792 return SMP_UNSPECIFIED; 2793 2794 smp_dev = hchan->data; 2795 2796 tfm_ecdh = smp_dev->tfm_ecdh; 2797 } else { 2798 tfm_ecdh = smp->tfm_ecdh; 2799 } 2800 2801 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey)) 2802 return SMP_UNSPECIFIED; 2803 2804 SMP_DBG("DHKey %32phN", smp->dhkey); 2805 2806 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2807 2808 smp->method = sc_select_method(smp); 2809 2810 bt_dev_dbg(hdev, "selected method 0x%02x", smp->method); 2811 2812 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2813 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2814 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2815 else 2816 hcon->pending_sec_level = BT_SECURITY_FIPS; 2817 2818 if (!crypto_memneq(debug_pk, smp->remote_pk, 64)) 2819 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2820 2821 if (smp->method == DSP_PASSKEY) { 2822 get_random_bytes(&hcon->passkey_notify, 2823 sizeof(hcon->passkey_notify)); 2824 hcon->passkey_notify %= 1000000; 2825 hcon->passkey_entered = 0; 2826 smp->passkey_round = 0; 2827 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2828 hcon->dst_type, 2829 hcon->passkey_notify, 2830 hcon->passkey_entered)) 2831 return SMP_UNSPECIFIED; 2832 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2833 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2834 } 2835 2836 if (smp->method == REQ_OOB) { 2837 if (hcon->out) 2838 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2839 sizeof(smp->prnd), smp->prnd); 2840 2841 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2842 2843 return 0; 2844 } 2845 2846 if (hcon->out) 2847 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2848 2849 if (smp->method == REQ_PASSKEY) { 2850 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2851 hcon->dst_type)) 2852 return SMP_UNSPECIFIED; 2853 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2854 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2855 return 0; 2856 } 2857 2858 /* The Initiating device waits for the non-initiating device to 2859 * send the confirm value. 2860 */ 2861 if (conn->hcon->out) 2862 return 0; 2863 2864 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2865 0, cfm.confirm_val); 2866 if (err) 2867 return SMP_UNSPECIFIED; 2868 2869 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2870 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2871 2872 return 0; 2873} 2874 2875static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2876{ 2877 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2878 struct l2cap_chan *chan = conn->smp; 2879 struct hci_conn *hcon = conn->hcon; 2880 struct smp_chan *smp = chan->data; 2881 u8 a[7], b[7], *local_addr, *remote_addr; 2882 u8 io_cap[3], r[16], e[16]; 2883 int err; 2884 2885 bt_dev_dbg(hcon->hdev, "conn %p", conn); 2886 2887 if (skb->len < sizeof(*check)) 2888 return SMP_INVALID_PARAMS; 2889 2890 memcpy(a, &hcon->init_addr, 6); 2891 memcpy(b, &hcon->resp_addr, 6); 2892 a[6] = hcon->init_addr_type; 2893 b[6] = hcon->resp_addr_type; 2894 2895 if (hcon->out) { 2896 local_addr = a; 2897 remote_addr = b; 2898 memcpy(io_cap, &smp->prsp[1], 3); 2899 } else { 2900 local_addr = b; 2901 remote_addr = a; 2902 memcpy(io_cap, &smp->preq[1], 3); 2903 } 2904 2905 memset(r, 0, sizeof(r)); 2906 2907 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2908 put_unaligned_le32(hcon->passkey_notify, r); 2909 else if (smp->method == REQ_OOB) 2910 memcpy(r, smp->lr, 16); 2911 2912 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2913 io_cap, remote_addr, local_addr, e); 2914 if (err) 2915 return SMP_UNSPECIFIED; 2916 2917 if (crypto_memneq(check->e, e, 16)) 2918 return SMP_DHKEY_CHECK_FAILED; 2919 2920 if (!hcon->out) { 2921 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2922 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2923 return 0; 2924 } 2925 2926 /* Responder sends DHKey check as response to initiator */ 2927 sc_dhkey_check(smp); 2928 } 2929 2930 sc_add_ltk(smp); 2931 2932 if (hcon->out) { 2933 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2934 hcon->enc_key_size = smp->enc_key_size; 2935 } 2936 2937 return 0; 2938} 2939 2940static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2941 struct sk_buff *skb) 2942{ 2943 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2944 2945 bt_dev_dbg(conn->hcon->hdev, "value 0x%02x", kp->value); 2946 2947 return 0; 2948} 2949 2950static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2951{ 2952 struct l2cap_conn *conn = chan->conn; 2953 struct hci_conn *hcon = conn->hcon; 2954 struct smp_chan *smp; 2955 __u8 code, reason; 2956 int err = 0; 2957 2958 if (skb->len < 1) 2959 return -EILSEQ; 2960 2961 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2962 reason = SMP_PAIRING_NOTSUPP; 2963 goto done; 2964 } 2965 2966 code = skb->data[0]; 2967 skb_pull(skb, sizeof(code)); 2968 2969 smp = chan->data; 2970 2971 if (code > SMP_CMD_MAX) 2972 goto drop; 2973 2974 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2975 goto drop; 2976 2977 /* If we don't have a context the only allowed commands are 2978 * pairing request and security request. 2979 */ 2980 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2981 goto drop; 2982 2983 switch (code) { 2984 case SMP_CMD_PAIRING_REQ: 2985 reason = smp_cmd_pairing_req(conn, skb); 2986 break; 2987 2988 case SMP_CMD_PAIRING_FAIL: 2989 smp_failure(conn, 0); 2990 err = -EPERM; 2991 break; 2992 2993 case SMP_CMD_PAIRING_RSP: 2994 reason = smp_cmd_pairing_rsp(conn, skb); 2995 break; 2996 2997 case SMP_CMD_SECURITY_REQ: 2998 reason = smp_cmd_security_req(conn, skb); 2999 break; 3000 3001 case SMP_CMD_PAIRING_CONFIRM: 3002 reason = smp_cmd_pairing_confirm(conn, skb); 3003 break; 3004 3005 case SMP_CMD_PAIRING_RANDOM: 3006 reason = smp_cmd_pairing_random(conn, skb); 3007 break; 3008 3009 case SMP_CMD_ENCRYPT_INFO: 3010 reason = smp_cmd_encrypt_info(conn, skb); 3011 break; 3012 3013 case SMP_CMD_INITIATOR_IDENT: 3014 reason = smp_cmd_initiator_ident(conn, skb); 3015 break; 3016 3017 case SMP_CMD_IDENT_INFO: 3018 reason = smp_cmd_ident_info(conn, skb); 3019 break; 3020 3021 case SMP_CMD_IDENT_ADDR_INFO: 3022 reason = smp_cmd_ident_addr_info(conn, skb); 3023 break; 3024 3025 case SMP_CMD_SIGN_INFO: 3026 reason = smp_cmd_sign_info(conn, skb); 3027 break; 3028 3029 case SMP_CMD_PUBLIC_KEY: 3030 reason = smp_cmd_public_key(conn, skb); 3031 break; 3032 3033 case SMP_CMD_DHKEY_CHECK: 3034 reason = smp_cmd_dhkey_check(conn, skb); 3035 break; 3036 3037 case SMP_CMD_KEYPRESS_NOTIFY: 3038 reason = smp_cmd_keypress_notify(conn, skb); 3039 break; 3040 3041 default: 3042 bt_dev_dbg(hcon->hdev, "Unknown command code 0x%2.2x", code); 3043 reason = SMP_CMD_NOTSUPP; 3044 goto done; 3045 } 3046 3047done: 3048 if (!err) { 3049 if (reason) 3050 smp_failure(conn, reason); 3051 kfree_skb(skb); 3052 } 3053 3054 return err; 3055 3056drop: 3057 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR", 3058 code, &hcon->dst); 3059 kfree_skb(skb); 3060 return 0; 3061} 3062 3063static void smp_teardown_cb(struct l2cap_chan *chan, int err) 3064{ 3065 struct l2cap_conn *conn = chan->conn; 3066 3067 bt_dev_dbg(conn->hcon->hdev, "chan %p", chan); 3068 3069 if (chan->data) 3070 smp_chan_destroy(conn); 3071 3072 conn->smp = NULL; 3073 l2cap_chan_put(chan); 3074} 3075 3076static void bredr_pairing(struct l2cap_chan *chan) 3077{ 3078 struct l2cap_conn *conn = chan->conn; 3079 struct hci_conn *hcon = conn->hcon; 3080 struct hci_dev *hdev = hcon->hdev; 3081 struct smp_cmd_pairing req; 3082 struct smp_chan *smp; 3083 3084 bt_dev_dbg(hdev, "chan %p", chan); 3085 3086 /* Only new pairings are interesting */ 3087 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 3088 return; 3089 3090 /* Don't bother if we're not encrypted */ 3091 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3092 return; 3093 3094 /* Only initiator may initiate SMP over BR/EDR */ 3095 if (hcon->role != HCI_ROLE_MASTER) 3096 return; 3097 3098 /* Secure Connections support must be enabled */ 3099 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 3100 return; 3101 3102 /* BR/EDR must use Secure Connections for SMP */ 3103 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 3104 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3105 return; 3106 3107 /* If our LE support is not enabled don't do anything */ 3108 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 3109 return; 3110 3111 /* Don't bother if remote LE support is not enabled */ 3112 if (!lmp_host_le_capable(hcon)) 3113 return; 3114 3115 /* Remote must support SMP fixed chan for BR/EDR */ 3116 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 3117 return; 3118 3119 /* Don't bother if SMP is already ongoing */ 3120 if (chan->data) 3121 return; 3122 3123 smp = smp_chan_create(conn); 3124 if (!smp) { 3125 bt_dev_err(hdev, "unable to create SMP context for BR/EDR"); 3126 return; 3127 } 3128 3129 set_bit(SMP_FLAG_SC, &smp->flags); 3130 3131 bt_dev_dbg(hdev, "starting SMP over BR/EDR"); 3132 3133 /* Prepare and send the BR/EDR SMP Pairing Request */ 3134 build_bredr_pairing_cmd(smp, &req, NULL); 3135 3136 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3137 memcpy(&smp->preq[1], &req, sizeof(req)); 3138 3139 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3140 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3141} 3142 3143static void smp_resume_cb(struct l2cap_chan *chan) 3144{ 3145 struct smp_chan *smp = chan->data; 3146 struct l2cap_conn *conn = chan->conn; 3147 struct hci_conn *hcon = conn->hcon; 3148 3149 bt_dev_dbg(hcon->hdev, "chan %p", chan); 3150 3151 if (hcon->type == ACL_LINK) { 3152 bredr_pairing(chan); 3153 return; 3154 } 3155 3156 if (!smp) 3157 return; 3158 3159 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3160 return; 3161 3162 cancel_delayed_work(&smp->security_timer); 3163 3164 smp_distribute_keys(smp); 3165} 3166 3167static void smp_ready_cb(struct l2cap_chan *chan) 3168{ 3169 struct l2cap_conn *conn = chan->conn; 3170 struct hci_conn *hcon = conn->hcon; 3171 3172 bt_dev_dbg(hcon->hdev, "chan %p", chan); 3173 3174 /* No need to call l2cap_chan_hold() here since we already own 3175 * the reference taken in smp_new_conn_cb(). This is just the 3176 * first time that we tie it to a specific pointer. The code in 3177 * l2cap_core.c ensures that there's no risk this function wont 3178 * get called if smp_new_conn_cb was previously called. 3179 */ 3180 conn->smp = chan; 3181 3182 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3183 bredr_pairing(chan); 3184} 3185 3186static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3187{ 3188 int err; 3189 3190 bt_dev_dbg(chan->conn->hcon->hdev, "chan %p", chan); 3191 3192 err = smp_sig_channel(chan, skb); 3193 if (err) { 3194 struct smp_chan *smp = chan->data; 3195 3196 if (smp) 3197 cancel_delayed_work_sync(&smp->security_timer); 3198 3199 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3200 } 3201 3202 return err; 3203} 3204 3205static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3206 unsigned long hdr_len, 3207 unsigned long len, int nb) 3208{ 3209 struct sk_buff *skb; 3210 3211 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3212 if (!skb) 3213 return ERR_PTR(-ENOMEM); 3214 3215 skb->priority = HCI_PRIO_MAX; 3216 bt_cb(skb)->l2cap.chan = chan; 3217 3218 return skb; 3219} 3220 3221static const struct l2cap_ops smp_chan_ops = { 3222 .name = "Security Manager", 3223 .ready = smp_ready_cb, 3224 .recv = smp_recv_cb, 3225 .alloc_skb = smp_alloc_skb_cb, 3226 .teardown = smp_teardown_cb, 3227 .resume = smp_resume_cb, 3228 3229 .new_connection = l2cap_chan_no_new_connection, 3230 .state_change = l2cap_chan_no_state_change, 3231 .close = l2cap_chan_no_close, 3232 .defer = l2cap_chan_no_defer, 3233 .suspend = l2cap_chan_no_suspend, 3234 .set_shutdown = l2cap_chan_no_set_shutdown, 3235 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3236}; 3237 3238static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3239{ 3240 struct l2cap_chan *chan; 3241 3242 BT_DBG("pchan %p", pchan); 3243 3244 chan = l2cap_chan_create(); 3245 if (!chan) 3246 return NULL; 3247 3248 chan->chan_type = pchan->chan_type; 3249 chan->ops = &smp_chan_ops; 3250 chan->scid = pchan->scid; 3251 chan->dcid = chan->scid; 3252 chan->imtu = pchan->imtu; 3253 chan->omtu = pchan->omtu; 3254 chan->mode = pchan->mode; 3255 3256 /* Other L2CAP channels may request SMP routines in order to 3257 * change the security level. This means that the SMP channel 3258 * lock must be considered in its own category to avoid lockdep 3259 * warnings. 3260 */ 3261 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3262 3263 BT_DBG("created chan %p", chan); 3264 3265 return chan; 3266} 3267 3268static const struct l2cap_ops smp_root_chan_ops = { 3269 .name = "Security Manager Root", 3270 .new_connection = smp_new_conn_cb, 3271 3272 /* None of these are implemented for the root channel */ 3273 .close = l2cap_chan_no_close, 3274 .alloc_skb = l2cap_chan_no_alloc_skb, 3275 .recv = l2cap_chan_no_recv, 3276 .state_change = l2cap_chan_no_state_change, 3277 .teardown = l2cap_chan_no_teardown, 3278 .ready = l2cap_chan_no_ready, 3279 .defer = l2cap_chan_no_defer, 3280 .suspend = l2cap_chan_no_suspend, 3281 .resume = l2cap_chan_no_resume, 3282 .set_shutdown = l2cap_chan_no_set_shutdown, 3283 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3284}; 3285 3286static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3287{ 3288 struct l2cap_chan *chan; 3289 struct smp_dev *smp; 3290 struct crypto_shash *tfm_cmac; 3291 struct crypto_kpp *tfm_ecdh; 3292 3293 if (cid == L2CAP_CID_SMP_BREDR) { 3294 smp = NULL; 3295 goto create_chan; 3296 } 3297 3298 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3299 if (!smp) 3300 return ERR_PTR(-ENOMEM); 3301 3302 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3303 if (IS_ERR(tfm_cmac)) { 3304 bt_dev_err(hdev, "Unable to create CMAC crypto context"); 3305 kfree_sensitive(smp); 3306 return ERR_CAST(tfm_cmac); 3307 } 3308 3309 tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 3310 if (IS_ERR(tfm_ecdh)) { 3311 bt_dev_err(hdev, "Unable to create ECDH crypto context"); 3312 crypto_free_shash(tfm_cmac); 3313 kfree_sensitive(smp); 3314 return ERR_CAST(tfm_ecdh); 3315 } 3316 3317 smp->local_oob = false; 3318 smp->tfm_cmac = tfm_cmac; 3319 smp->tfm_ecdh = tfm_ecdh; 3320 3321create_chan: 3322 chan = l2cap_chan_create(); 3323 if (!chan) { 3324 if (smp) { 3325 crypto_free_shash(smp->tfm_cmac); 3326 crypto_free_kpp(smp->tfm_ecdh); 3327 kfree_sensitive(smp); 3328 } 3329 return ERR_PTR(-ENOMEM); 3330 } 3331 3332 chan->data = smp; 3333 3334 l2cap_add_scid(chan, cid); 3335 3336 l2cap_chan_set_defaults(chan); 3337 3338 if (cid == L2CAP_CID_SMP) { 3339 u8 bdaddr_type; 3340 3341 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3342 3343 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3344 chan->src_type = BDADDR_LE_PUBLIC; 3345 else 3346 chan->src_type = BDADDR_LE_RANDOM; 3347 } else { 3348 bacpy(&chan->src, &hdev->bdaddr); 3349 chan->src_type = BDADDR_BREDR; 3350 } 3351 3352 chan->state = BT_LISTEN; 3353 chan->mode = L2CAP_MODE_BASIC; 3354 chan->imtu = L2CAP_DEFAULT_MTU; 3355 chan->ops = &smp_root_chan_ops; 3356 3357 /* Set correct nesting level for a parent/listening channel */ 3358 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3359 3360 return chan; 3361} 3362 3363static void smp_del_chan(struct l2cap_chan *chan) 3364{ 3365 struct smp_dev *smp; 3366 3367 BT_DBG("chan %p", chan); 3368 3369 smp = chan->data; 3370 if (smp) { 3371 chan->data = NULL; 3372 crypto_free_shash(smp->tfm_cmac); 3373 crypto_free_kpp(smp->tfm_ecdh); 3374 kfree_sensitive(smp); 3375 } 3376 3377 l2cap_chan_put(chan); 3378} 3379 3380static ssize_t force_bredr_smp_read(struct file *file, 3381 char __user *user_buf, 3382 size_t count, loff_t *ppos) 3383{ 3384 struct hci_dev *hdev = file->private_data; 3385 char buf[3]; 3386 3387 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N'; 3388 buf[1] = '\n'; 3389 buf[2] = '\0'; 3390 return simple_read_from_buffer(user_buf, count, ppos, buf, 2); 3391} 3392 3393static ssize_t force_bredr_smp_write(struct file *file, 3394 const char __user *user_buf, 3395 size_t count, loff_t *ppos) 3396{ 3397 struct hci_dev *hdev = file->private_data; 3398 bool enable; 3399 int err; 3400 3401 err = kstrtobool_from_user(user_buf, count, &enable); 3402 if (err) 3403 return err; 3404 3405 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3406 return -EALREADY; 3407 3408 if (enable) { 3409 struct l2cap_chan *chan; 3410 3411 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3412 if (IS_ERR(chan)) 3413 return PTR_ERR(chan); 3414 3415 hdev->smp_bredr_data = chan; 3416 } else { 3417 struct l2cap_chan *chan; 3418 3419 chan = hdev->smp_bredr_data; 3420 hdev->smp_bredr_data = NULL; 3421 smp_del_chan(chan); 3422 } 3423 3424 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3425 3426 return count; 3427} 3428 3429static const struct file_operations force_bredr_smp_fops = { 3430 .open = simple_open, 3431 .read = force_bredr_smp_read, 3432 .write = force_bredr_smp_write, 3433 .llseek = default_llseek, 3434}; 3435 3436int smp_register(struct hci_dev *hdev) 3437{ 3438 struct l2cap_chan *chan; 3439 3440 bt_dev_dbg(hdev, ""); 3441 3442 /* If the controller does not support Low Energy operation, then 3443 * there is also no need to register any SMP channel. 3444 */ 3445 if (!lmp_le_capable(hdev)) 3446 return 0; 3447 3448 if (WARN_ON(hdev->smp_data)) { 3449 chan = hdev->smp_data; 3450 hdev->smp_data = NULL; 3451 smp_del_chan(chan); 3452 } 3453 3454 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3455 if (IS_ERR(chan)) 3456 return PTR_ERR(chan); 3457 3458 hdev->smp_data = chan; 3459 3460 /* If the controller does not support BR/EDR Secure Connections 3461 * feature, then the BR/EDR SMP channel shall not be present. 3462 * 3463 * To test this with Bluetooth 4.0 controllers, create a debugfs 3464 * switch that allows forcing BR/EDR SMP support and accepting 3465 * cross-transport pairing on non-AES encrypted connections. 3466 */ 3467 if (!lmp_sc_capable(hdev)) { 3468 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs, 3469 hdev, &force_bredr_smp_fops); 3470 3471 /* Flag can be already set here (due to power toggle) */ 3472 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3473 return 0; 3474 } 3475 3476 if (WARN_ON(hdev->smp_bredr_data)) { 3477 chan = hdev->smp_bredr_data; 3478 hdev->smp_bredr_data = NULL; 3479 smp_del_chan(chan); 3480 } 3481 3482 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3483 if (IS_ERR(chan)) { 3484 int err = PTR_ERR(chan); 3485 chan = hdev->smp_data; 3486 hdev->smp_data = NULL; 3487 smp_del_chan(chan); 3488 return err; 3489 } 3490 3491 hdev->smp_bredr_data = chan; 3492 3493 return 0; 3494} 3495 3496void smp_unregister(struct hci_dev *hdev) 3497{ 3498 struct l2cap_chan *chan; 3499 3500 if (hdev->smp_bredr_data) { 3501 chan = hdev->smp_bredr_data; 3502 hdev->smp_bredr_data = NULL; 3503 smp_del_chan(chan); 3504 } 3505 3506 if (hdev->smp_data) { 3507 chan = hdev->smp_data; 3508 hdev->smp_data = NULL; 3509 smp_del_chan(chan); 3510 } 3511} 3512 3513#if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3514 3515static int __init test_debug_key(struct crypto_kpp *tfm_ecdh) 3516{ 3517 u8 pk[64]; 3518 int err; 3519 3520 err = set_ecdh_privkey(tfm_ecdh, debug_sk); 3521 if (err) 3522 return err; 3523 3524 err = generate_ecdh_public_key(tfm_ecdh, pk); 3525 if (err) 3526 return err; 3527 3528 if (crypto_memneq(pk, debug_pk, 64)) 3529 return -EINVAL; 3530 3531 return 0; 3532} 3533 3534static int __init test_ah(void) 3535{ 3536 const u8 irk[16] = { 3537 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3538 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3539 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3540 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3541 u8 res[3]; 3542 int err; 3543 3544 err = smp_ah(irk, r, res); 3545 if (err) 3546 return err; 3547 3548 if (crypto_memneq(res, exp, 3)) 3549 return -EINVAL; 3550 3551 return 0; 3552} 3553 3554static int __init test_c1(void) 3555{ 3556 const u8 k[16] = { 3557 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3558 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3559 const u8 r[16] = { 3560 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3561 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3562 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3563 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3564 const u8 _iat = 0x01; 3565 const u8 _rat = 0x00; 3566 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3567 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3568 const u8 exp[16] = { 3569 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3570 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3571 u8 res[16]; 3572 int err; 3573 3574 err = smp_c1(k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3575 if (err) 3576 return err; 3577 3578 if (crypto_memneq(res, exp, 16)) 3579 return -EINVAL; 3580 3581 return 0; 3582} 3583 3584static int __init test_s1(void) 3585{ 3586 const u8 k[16] = { 3587 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3588 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3589 const u8 r1[16] = { 3590 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3591 const u8 r2[16] = { 3592 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3593 const u8 exp[16] = { 3594 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3595 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3596 u8 res[16]; 3597 int err; 3598 3599 err = smp_s1(k, r1, r2, res); 3600 if (err) 3601 return err; 3602 3603 if (crypto_memneq(res, exp, 16)) 3604 return -EINVAL; 3605 3606 return 0; 3607} 3608 3609static int __init test_f4(struct crypto_shash *tfm_cmac) 3610{ 3611 const u8 u[32] = { 3612 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3613 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3614 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3615 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3616 const u8 v[32] = { 3617 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3618 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3619 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3620 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3621 const u8 x[16] = { 3622 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3623 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3624 const u8 z = 0x00; 3625 const u8 exp[16] = { 3626 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3627 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3628 u8 res[16]; 3629 int err; 3630 3631 err = smp_f4(tfm_cmac, u, v, x, z, res); 3632 if (err) 3633 return err; 3634 3635 if (crypto_memneq(res, exp, 16)) 3636 return -EINVAL; 3637 3638 return 0; 3639} 3640 3641static int __init test_f5(struct crypto_shash *tfm_cmac) 3642{ 3643 const u8 w[32] = { 3644 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3645 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3646 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3647 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3648 const u8 n1[16] = { 3649 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3650 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3651 const u8 n2[16] = { 3652 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3653 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3654 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3655 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3656 const u8 exp_ltk[16] = { 3657 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3658 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3659 const u8 exp_mackey[16] = { 3660 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3661 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3662 u8 mackey[16], ltk[16]; 3663 int err; 3664 3665 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3666 if (err) 3667 return err; 3668 3669 if (crypto_memneq(mackey, exp_mackey, 16)) 3670 return -EINVAL; 3671 3672 if (crypto_memneq(ltk, exp_ltk, 16)) 3673 return -EINVAL; 3674 3675 return 0; 3676} 3677 3678static int __init test_f6(struct crypto_shash *tfm_cmac) 3679{ 3680 const u8 w[16] = { 3681 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3682 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3683 const u8 n1[16] = { 3684 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3685 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3686 const u8 n2[16] = { 3687 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3688 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3689 const u8 r[16] = { 3690 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3691 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3692 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3693 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3694 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3695 const u8 exp[16] = { 3696 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3697 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3698 u8 res[16]; 3699 int err; 3700 3701 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3702 if (err) 3703 return err; 3704 3705 if (crypto_memneq(res, exp, 16)) 3706 return -EINVAL; 3707 3708 return 0; 3709} 3710 3711static int __init test_g2(struct crypto_shash *tfm_cmac) 3712{ 3713 const u8 u[32] = { 3714 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3715 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3716 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3717 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3718 const u8 v[32] = { 3719 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3720 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3721 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3722 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3723 const u8 x[16] = { 3724 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3725 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3726 const u8 y[16] = { 3727 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3728 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3729 const u32 exp_val = 0x2f9ed5ba % 1000000; 3730 u32 val; 3731 int err; 3732 3733 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3734 if (err) 3735 return err; 3736 3737 if (val != exp_val) 3738 return -EINVAL; 3739 3740 return 0; 3741} 3742 3743static int __init test_h6(struct crypto_shash *tfm_cmac) 3744{ 3745 const u8 w[16] = { 3746 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3747 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3748 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3749 const u8 exp[16] = { 3750 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3751 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3752 u8 res[16]; 3753 int err; 3754 3755 err = smp_h6(tfm_cmac, w, key_id, res); 3756 if (err) 3757 return err; 3758 3759 if (crypto_memneq(res, exp, 16)) 3760 return -EINVAL; 3761 3762 return 0; 3763} 3764 3765static char test_smp_buffer[32]; 3766 3767static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3768 size_t count, loff_t *ppos) 3769{ 3770 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3771 strlen(test_smp_buffer)); 3772} 3773 3774static const struct file_operations test_smp_fops = { 3775 .open = simple_open, 3776 .read = test_smp_read, 3777 .llseek = default_llseek, 3778}; 3779 3780static int __init run_selftests(struct crypto_shash *tfm_cmac, 3781 struct crypto_kpp *tfm_ecdh) 3782{ 3783 ktime_t calltime, delta, rettime; 3784 unsigned long long duration; 3785 int err; 3786 3787 calltime = ktime_get(); 3788 3789 err = test_debug_key(tfm_ecdh); 3790 if (err) { 3791 BT_ERR("debug_key test failed"); 3792 goto done; 3793 } 3794 3795 err = test_ah(); 3796 if (err) { 3797 BT_ERR("smp_ah test failed"); 3798 goto done; 3799 } 3800 3801 err = test_c1(); 3802 if (err) { 3803 BT_ERR("smp_c1 test failed"); 3804 goto done; 3805 } 3806 3807 err = test_s1(); 3808 if (err) { 3809 BT_ERR("smp_s1 test failed"); 3810 goto done; 3811 } 3812 3813 err = test_f4(tfm_cmac); 3814 if (err) { 3815 BT_ERR("smp_f4 test failed"); 3816 goto done; 3817 } 3818 3819 err = test_f5(tfm_cmac); 3820 if (err) { 3821 BT_ERR("smp_f5 test failed"); 3822 goto done; 3823 } 3824 3825 err = test_f6(tfm_cmac); 3826 if (err) { 3827 BT_ERR("smp_f6 test failed"); 3828 goto done; 3829 } 3830 3831 err = test_g2(tfm_cmac); 3832 if (err) { 3833 BT_ERR("smp_g2 test failed"); 3834 goto done; 3835 } 3836 3837 err = test_h6(tfm_cmac); 3838 if (err) { 3839 BT_ERR("smp_h6 test failed"); 3840 goto done; 3841 } 3842 3843 rettime = ktime_get(); 3844 delta = ktime_sub(rettime, calltime); 3845 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3846 3847 BT_INFO("SMP test passed in %llu usecs", duration); 3848 3849done: 3850 if (!err) 3851 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3852 "PASS (%llu usecs)\n", duration); 3853 else 3854 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3855 3856 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3857 &test_smp_fops); 3858 3859 return err; 3860} 3861 3862int __init bt_selftest_smp(void) 3863{ 3864 struct crypto_shash *tfm_cmac; 3865 struct crypto_kpp *tfm_ecdh; 3866 int err; 3867 3868 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3869 if (IS_ERR(tfm_cmac)) { 3870 BT_ERR("Unable to create CMAC crypto context"); 3871 return PTR_ERR(tfm_cmac); 3872 } 3873 3874 tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 3875 if (IS_ERR(tfm_ecdh)) { 3876 BT_ERR("Unable to create ECDH crypto context"); 3877 crypto_free_shash(tfm_cmac); 3878 return PTR_ERR(tfm_ecdh); 3879 } 3880 3881 err = run_selftests(tfm_cmac, tfm_ecdh); 3882 3883 crypto_free_shash(tfm_cmac); 3884 crypto_free_kpp(tfm_ecdh); 3885 3886 return err; 3887} 3888 3889#endif 3890