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/b128ops.h> 27 #include <crypto/hash.h> 28 29 #include <net/bluetooth/bluetooth.h> 30 #include <net/bluetooth/hci_core.h> 31 #include <net/bluetooth/l2cap.h> 32 #include <net/bluetooth/mgmt.h> 33 34 #include "ecc.h" 35 #include "smp.h" 36 37 #define SMP_DEV(hdev) \ 38 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data) 39 40 /* Low-level debug macros to be used for stuff that we don't want 41 * accidentially in dmesg, i.e. the values of the various crypto keys 42 * and the inputs & outputs of crypto functions. 43 */ 44 #ifdef DEBUG 45 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \ 46 ##__VA_ARGS__) 47 #else 48 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \ 49 ##__VA_ARGS__) 50 #endif 51 52 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) 53 54 /* Keys which are not distributed with Secure Connections */ 55 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY); 56 57 #define SMP_TIMEOUT msecs_to_jiffies(30000) 58 59 #define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \ 60 0x3f : 0x07) 61 #define KEY_DIST_MASK 0x07 62 63 /* Maximum message length that can be passed to aes_cmac */ 64 #define CMAC_MSG_MAX 80 65 66 enum { 67 SMP_FLAG_TK_VALID, 68 SMP_FLAG_CFM_PENDING, 69 SMP_FLAG_MITM_AUTH, 70 SMP_FLAG_COMPLETE, 71 SMP_FLAG_INITIATOR, 72 SMP_FLAG_SC, 73 SMP_FLAG_REMOTE_PK, 74 SMP_FLAG_DEBUG_KEY, 75 SMP_FLAG_WAIT_USER, 76 SMP_FLAG_DHKEY_PENDING, 77 SMP_FLAG_REMOTE_OOB, 78 SMP_FLAG_LOCAL_OOB, 79 SMP_FLAG_CT2, 80 }; 81 82 struct smp_dev { 83 /* Secure Connections OOB data */ 84 u8 local_pk[64]; 85 u8 local_sk[32]; 86 u8 local_rand[16]; 87 bool debug_key; 88 89 u8 min_key_size; 90 u8 max_key_size; 91 92 struct crypto_cipher *tfm_aes; 93 struct crypto_shash *tfm_cmac; 94 }; 95 96 struct 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 *slave_csrk; 116 struct smp_ltk *ltk; 117 struct smp_ltk *slave_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 local_sk[32]; 127 u8 remote_pk[64]; 128 u8 dhkey[32]; 129 u8 mackey[16]; 130 131 struct crypto_cipher *tfm_aes; 132 struct crypto_shash *tfm_cmac; 133 }; 134 135 /* These debug key values are defined in the SMP section of the core 136 * specification. debug_pk is the public debug key and debug_sk the 137 * private debug key. 138 */ 139 static const u8 debug_pk[64] = { 140 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 141 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 142 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 143 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 144 145 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 146 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 147 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 148 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 149 }; 150 151 static const u8 debug_sk[32] = { 152 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 153 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 154 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 155 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 156 }; 157 158 static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 159 { 160 size_t i; 161 162 for (i = 0; i < len; i++) 163 dst[len - 1 - i] = src[i]; 164 } 165 166 /* The following functions map to the LE SC SMP crypto functions 167 * AES-CMAC, f4, f5, f6, g2 and h6. 168 */ 169 170 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 171 size_t len, u8 mac[16]) 172 { 173 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 174 SHASH_DESC_ON_STACK(desc, tfm); 175 int err; 176 177 if (len > CMAC_MSG_MAX) 178 return -EFBIG; 179 180 if (!tfm) { 181 BT_ERR("tfm %p", tfm); 182 return -EINVAL; 183 } 184 185 desc->tfm = tfm; 186 desc->flags = 0; 187 188 /* Swap key and message from LSB to MSB */ 189 swap_buf(k, tmp, 16); 190 swap_buf(m, msg_msb, len); 191 192 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 193 SMP_DBG("key %16phN", k); 194 195 err = crypto_shash_setkey(tfm, tmp, 16); 196 if (err) { 197 BT_ERR("cipher setkey failed: %d", err); 198 return err; 199 } 200 201 err = crypto_shash_digest(desc, msg_msb, len, mac_msb); 202 shash_desc_zero(desc); 203 if (err) { 204 BT_ERR("Hash computation error %d", err); 205 return err; 206 } 207 208 swap_buf(mac_msb, mac, 16); 209 210 SMP_DBG("mac %16phN", mac); 211 212 return 0; 213 } 214 215 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 216 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 217 { 218 u8 m[65]; 219 int err; 220 221 SMP_DBG("u %32phN", u); 222 SMP_DBG("v %32phN", v); 223 SMP_DBG("x %16phN z %02x", x, z); 224 225 m[0] = z; 226 memcpy(m + 1, v, 32); 227 memcpy(m + 33, u, 32); 228 229 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 230 if (err) 231 return err; 232 233 SMP_DBG("res %16phN", res); 234 235 return err; 236 } 237 238 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 239 const u8 n1[16], const u8 n2[16], const u8 a1[7], 240 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 241 { 242 /* The btle, salt and length "magic" values are as defined in 243 * the SMP section of the Bluetooth core specification. In ASCII 244 * the btle value ends up being 'btle'. The salt is just a 245 * random number whereas length is the value 256 in little 246 * endian format. 247 */ 248 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 249 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 250 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 251 const u8 length[2] = { 0x00, 0x01 }; 252 u8 m[53], t[16]; 253 int err; 254 255 SMP_DBG("w %32phN", w); 256 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 257 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 258 259 err = aes_cmac(tfm_cmac, salt, w, 32, t); 260 if (err) 261 return err; 262 263 SMP_DBG("t %16phN", t); 264 265 memcpy(m, length, 2); 266 memcpy(m + 2, a2, 7); 267 memcpy(m + 9, a1, 7); 268 memcpy(m + 16, n2, 16); 269 memcpy(m + 32, n1, 16); 270 memcpy(m + 48, btle, 4); 271 272 m[52] = 0; /* Counter */ 273 274 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 275 if (err) 276 return err; 277 278 SMP_DBG("mackey %16phN", mackey); 279 280 m[52] = 1; /* Counter */ 281 282 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 283 if (err) 284 return err; 285 286 SMP_DBG("ltk %16phN", ltk); 287 288 return 0; 289 } 290 291 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 292 const u8 n1[16], const u8 n2[16], const u8 r[16], 293 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 294 u8 res[16]) 295 { 296 u8 m[65]; 297 int err; 298 299 SMP_DBG("w %16phN", w); 300 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 301 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 302 303 memcpy(m, a2, 7); 304 memcpy(m + 7, a1, 7); 305 memcpy(m + 14, io_cap, 3); 306 memcpy(m + 17, r, 16); 307 memcpy(m + 33, n2, 16); 308 memcpy(m + 49, n1, 16); 309 310 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 311 if (err) 312 return err; 313 314 SMP_DBG("res %16phN", res); 315 316 return err; 317 } 318 319 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 320 const u8 x[16], const u8 y[16], u32 *val) 321 { 322 u8 m[80], tmp[16]; 323 int err; 324 325 SMP_DBG("u %32phN", u); 326 SMP_DBG("v %32phN", v); 327 SMP_DBG("x %16phN y %16phN", x, y); 328 329 memcpy(m, y, 16); 330 memcpy(m + 16, v, 32); 331 memcpy(m + 48, u, 32); 332 333 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 334 if (err) 335 return err; 336 337 *val = get_unaligned_le32(tmp); 338 *val %= 1000000; 339 340 SMP_DBG("val %06u", *val); 341 342 return 0; 343 } 344 345 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 346 const u8 key_id[4], u8 res[16]) 347 { 348 int err; 349 350 SMP_DBG("w %16phN key_id %4phN", w, key_id); 351 352 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 353 if (err) 354 return err; 355 356 SMP_DBG("res %16phN", res); 357 358 return err; 359 } 360 361 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 362 const u8 salt[16], u8 res[16]) 363 { 364 int err; 365 366 SMP_DBG("w %16phN salt %16phN", w, salt); 367 368 err = aes_cmac(tfm_cmac, salt, w, 16, res); 369 if (err) 370 return err; 371 372 SMP_DBG("res %16phN", res); 373 374 return err; 375 } 376 377 /* The following functions map to the legacy SMP crypto functions e, c1, 378 * s1 and ah. 379 */ 380 381 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r) 382 { 383 uint8_t tmp[16], data[16]; 384 int err; 385 386 SMP_DBG("k %16phN r %16phN", k, r); 387 388 if (!tfm) { 389 BT_ERR("tfm %p", tfm); 390 return -EINVAL; 391 } 392 393 /* The most significant octet of key corresponds to k[0] */ 394 swap_buf(k, tmp, 16); 395 396 err = crypto_cipher_setkey(tfm, tmp, 16); 397 if (err) { 398 BT_ERR("cipher setkey failed: %d", err); 399 return err; 400 } 401 402 /* Most significant octet of plaintextData corresponds to data[0] */ 403 swap_buf(r, data, 16); 404 405 crypto_cipher_encrypt_one(tfm, data, data); 406 407 /* Most significant octet of encryptedData corresponds to data[0] */ 408 swap_buf(data, r, 16); 409 410 SMP_DBG("r %16phN", r); 411 412 return err; 413 } 414 415 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16], 416 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 417 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 418 { 419 u8 p1[16], p2[16]; 420 int err; 421 422 SMP_DBG("k %16phN r %16phN", k, r); 423 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 424 SMP_DBG("preq %7phN pres %7phN", preq, pres); 425 426 memset(p1, 0, 16); 427 428 /* p1 = pres || preq || _rat || _iat */ 429 p1[0] = _iat; 430 p1[1] = _rat; 431 memcpy(p1 + 2, preq, 7); 432 memcpy(p1 + 9, pres, 7); 433 434 SMP_DBG("p1 %16phN", p1); 435 436 /* res = r XOR p1 */ 437 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); 438 439 /* res = e(k, res) */ 440 err = smp_e(tfm_aes, k, res); 441 if (err) { 442 BT_ERR("Encrypt data error"); 443 return err; 444 } 445 446 /* p2 = padding || ia || ra */ 447 memcpy(p2, ra, 6); 448 memcpy(p2 + 6, ia, 6); 449 memset(p2 + 12, 0, 4); 450 451 SMP_DBG("p2 %16phN", p2); 452 453 /* res = res XOR p2 */ 454 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); 455 456 /* res = e(k, res) */ 457 err = smp_e(tfm_aes, k, res); 458 if (err) 459 BT_ERR("Encrypt data error"); 460 461 return err; 462 } 463 464 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16], 465 const u8 r1[16], const u8 r2[16], u8 _r[16]) 466 { 467 int err; 468 469 /* Just least significant octets from r1 and r2 are considered */ 470 memcpy(_r, r2, 8); 471 memcpy(_r + 8, r1, 8); 472 473 err = smp_e(tfm_aes, k, _r); 474 if (err) 475 BT_ERR("Encrypt data error"); 476 477 return err; 478 } 479 480 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16], 481 const u8 r[3], u8 res[3]) 482 { 483 u8 _res[16]; 484 int err; 485 486 /* r' = padding || r */ 487 memcpy(_res, r, 3); 488 memset(_res + 3, 0, 13); 489 490 err = smp_e(tfm, irk, _res); 491 if (err) { 492 BT_ERR("Encrypt error"); 493 return err; 494 } 495 496 /* The output of the random address function ah is: 497 * ah(k, r) = e(k, r') mod 2^24 498 * The output of the security function e is then truncated to 24 bits 499 * by taking the least significant 24 bits of the output of e as the 500 * result of ah. 501 */ 502 memcpy(res, _res, 3); 503 504 return 0; 505 } 506 507 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 508 const bdaddr_t *bdaddr) 509 { 510 struct l2cap_chan *chan = hdev->smp_data; 511 struct smp_dev *smp; 512 u8 hash[3]; 513 int err; 514 515 if (!chan || !chan->data) 516 return false; 517 518 smp = chan->data; 519 520 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk); 521 522 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash); 523 if (err) 524 return false; 525 526 return !memcmp(bdaddr->b, hash, 3); 527 } 528 529 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 530 { 531 struct l2cap_chan *chan = hdev->smp_data; 532 struct smp_dev *smp; 533 int err; 534 535 if (!chan || !chan->data) 536 return -EOPNOTSUPP; 537 538 smp = chan->data; 539 540 get_random_bytes(&rpa->b[3], 3); 541 542 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 543 rpa->b[5] |= 0x40; /* Set second most significant bit */ 544 545 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b); 546 if (err < 0) 547 return err; 548 549 BT_DBG("RPA %pMR", rpa); 550 551 return 0; 552 } 553 554 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 555 { 556 struct l2cap_chan *chan = hdev->smp_data; 557 struct smp_dev *smp; 558 int err; 559 560 if (!chan || !chan->data) 561 return -EOPNOTSUPP; 562 563 smp = chan->data; 564 565 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 566 BT_DBG("Using debug keys"); 567 memcpy(smp->local_pk, debug_pk, 64); 568 memcpy(smp->local_sk, debug_sk, 32); 569 smp->debug_key = true; 570 } else { 571 while (true) { 572 /* Generate local key pair for Secure Connections */ 573 if (!ecc_make_key(smp->local_pk, smp->local_sk)) 574 return -EIO; 575 576 /* This is unlikely, but we need to check that 577 * we didn't accidentially generate a debug key. 578 */ 579 if (memcmp(smp->local_sk, debug_sk, 32)) 580 break; 581 } 582 smp->debug_key = false; 583 } 584 585 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 586 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 587 SMP_DBG("OOB Private Key: %32phN", smp->local_sk); 588 589 get_random_bytes(smp->local_rand, 16); 590 591 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 592 smp->local_rand, 0, hash); 593 if (err < 0) 594 return err; 595 596 memcpy(rand, smp->local_rand, 16); 597 598 return 0; 599 } 600 601 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 602 { 603 struct l2cap_chan *chan = conn->smp; 604 struct smp_chan *smp; 605 struct kvec iv[2]; 606 struct msghdr msg; 607 608 if (!chan) 609 return; 610 611 BT_DBG("code 0x%2.2x", code); 612 613 iv[0].iov_base = &code; 614 iv[0].iov_len = 1; 615 616 iv[1].iov_base = data; 617 iv[1].iov_len = len; 618 619 memset(&msg, 0, sizeof(msg)); 620 621 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len); 622 623 l2cap_chan_send(chan, &msg, 1 + len); 624 625 if (!chan->data) 626 return; 627 628 smp = chan->data; 629 630 cancel_delayed_work_sync(&smp->security_timer); 631 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 632 } 633 634 static u8 authreq_to_seclevel(u8 authreq) 635 { 636 if (authreq & SMP_AUTH_MITM) { 637 if (authreq & SMP_AUTH_SC) 638 return BT_SECURITY_FIPS; 639 else 640 return BT_SECURITY_HIGH; 641 } else { 642 return BT_SECURITY_MEDIUM; 643 } 644 } 645 646 static __u8 seclevel_to_authreq(__u8 sec_level) 647 { 648 switch (sec_level) { 649 case BT_SECURITY_FIPS: 650 case BT_SECURITY_HIGH: 651 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 652 case BT_SECURITY_MEDIUM: 653 return SMP_AUTH_BONDING; 654 default: 655 return SMP_AUTH_NONE; 656 } 657 } 658 659 static void build_pairing_cmd(struct l2cap_conn *conn, 660 struct smp_cmd_pairing *req, 661 struct smp_cmd_pairing *rsp, __u8 authreq) 662 { 663 struct l2cap_chan *chan = conn->smp; 664 struct smp_chan *smp = chan->data; 665 struct hci_conn *hcon = conn->hcon; 666 struct hci_dev *hdev = hcon->hdev; 667 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 668 669 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 670 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 671 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 672 authreq |= SMP_AUTH_BONDING; 673 } else { 674 authreq &= ~SMP_AUTH_BONDING; 675 } 676 677 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 678 remote_dist |= SMP_DIST_ID_KEY; 679 680 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 681 local_dist |= SMP_DIST_ID_KEY; 682 683 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 684 (authreq & SMP_AUTH_SC)) { 685 struct oob_data *oob_data; 686 u8 bdaddr_type; 687 688 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 689 local_dist |= SMP_DIST_LINK_KEY; 690 remote_dist |= SMP_DIST_LINK_KEY; 691 } 692 693 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 694 bdaddr_type = BDADDR_LE_PUBLIC; 695 else 696 bdaddr_type = BDADDR_LE_RANDOM; 697 698 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 699 bdaddr_type); 700 if (oob_data && oob_data->present) { 701 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 702 oob_flag = SMP_OOB_PRESENT; 703 memcpy(smp->rr, oob_data->rand256, 16); 704 memcpy(smp->pcnf, oob_data->hash256, 16); 705 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 706 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 707 } 708 709 } else { 710 authreq &= ~SMP_AUTH_SC; 711 } 712 713 if (rsp == NULL) { 714 req->io_capability = conn->hcon->io_capability; 715 req->oob_flag = oob_flag; 716 req->max_key_size = SMP_DEV(hdev)->max_key_size; 717 req->init_key_dist = local_dist; 718 req->resp_key_dist = remote_dist; 719 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 720 721 smp->remote_key_dist = remote_dist; 722 return; 723 } 724 725 rsp->io_capability = conn->hcon->io_capability; 726 rsp->oob_flag = oob_flag; 727 rsp->max_key_size = SMP_DEV(hdev)->max_key_size; 728 rsp->init_key_dist = req->init_key_dist & remote_dist; 729 rsp->resp_key_dist = req->resp_key_dist & local_dist; 730 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 731 732 smp->remote_key_dist = rsp->init_key_dist; 733 } 734 735 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 736 { 737 struct l2cap_chan *chan = conn->smp; 738 struct hci_dev *hdev = conn->hcon->hdev; 739 struct smp_chan *smp = chan->data; 740 741 if (max_key_size > SMP_DEV(hdev)->max_key_size || 742 max_key_size < SMP_MIN_ENC_KEY_SIZE) 743 return SMP_ENC_KEY_SIZE; 744 745 smp->enc_key_size = max_key_size; 746 747 return 0; 748 } 749 750 static void smp_chan_destroy(struct l2cap_conn *conn) 751 { 752 struct l2cap_chan *chan = conn->smp; 753 struct smp_chan *smp = chan->data; 754 struct hci_conn *hcon = conn->hcon; 755 bool complete; 756 757 BUG_ON(!smp); 758 759 cancel_delayed_work_sync(&smp->security_timer); 760 761 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 762 mgmt_smp_complete(hcon, complete); 763 764 kzfree(smp->csrk); 765 kzfree(smp->slave_csrk); 766 kzfree(smp->link_key); 767 768 crypto_free_cipher(smp->tfm_aes); 769 crypto_free_shash(smp->tfm_cmac); 770 771 /* Ensure that we don't leave any debug key around if debug key 772 * support hasn't been explicitly enabled. 773 */ 774 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 775 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 776 list_del_rcu(&smp->ltk->list); 777 kfree_rcu(smp->ltk, rcu); 778 smp->ltk = NULL; 779 } 780 781 /* If pairing failed clean up any keys we might have */ 782 if (!complete) { 783 if (smp->ltk) { 784 list_del_rcu(&smp->ltk->list); 785 kfree_rcu(smp->ltk, rcu); 786 } 787 788 if (smp->slave_ltk) { 789 list_del_rcu(&smp->slave_ltk->list); 790 kfree_rcu(smp->slave_ltk, rcu); 791 } 792 793 if (smp->remote_irk) { 794 list_del_rcu(&smp->remote_irk->list); 795 kfree_rcu(smp->remote_irk, rcu); 796 } 797 } 798 799 chan->data = NULL; 800 kzfree(smp); 801 hci_conn_drop(hcon); 802 } 803 804 static void smp_failure(struct l2cap_conn *conn, u8 reason) 805 { 806 struct hci_conn *hcon = conn->hcon; 807 struct l2cap_chan *chan = conn->smp; 808 809 if (reason) 810 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 811 &reason); 812 813 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 814 815 if (chan->data) 816 smp_chan_destroy(conn); 817 } 818 819 #define JUST_WORKS 0x00 820 #define JUST_CFM 0x01 821 #define REQ_PASSKEY 0x02 822 #define CFM_PASSKEY 0x03 823 #define REQ_OOB 0x04 824 #define DSP_PASSKEY 0x05 825 #define OVERLAP 0xFF 826 827 static const u8 gen_method[5][5] = { 828 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 829 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 830 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 831 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 832 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 833 }; 834 835 static const u8 sc_method[5][5] = { 836 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 837 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 838 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 839 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 840 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 841 }; 842 843 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 844 { 845 /* If either side has unknown io_caps, use JUST_CFM (which gets 846 * converted later to JUST_WORKS if we're initiators. 847 */ 848 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 849 remote_io > SMP_IO_KEYBOARD_DISPLAY) 850 return JUST_CFM; 851 852 if (test_bit(SMP_FLAG_SC, &smp->flags)) 853 return sc_method[remote_io][local_io]; 854 855 return gen_method[remote_io][local_io]; 856 } 857 858 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 859 u8 local_io, u8 remote_io) 860 { 861 struct hci_conn *hcon = conn->hcon; 862 struct l2cap_chan *chan = conn->smp; 863 struct smp_chan *smp = chan->data; 864 u32 passkey = 0; 865 int ret = 0; 866 867 /* Initialize key for JUST WORKS */ 868 memset(smp->tk, 0, sizeof(smp->tk)); 869 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 870 871 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); 872 873 /* If neither side wants MITM, either "just" confirm an incoming 874 * request or use just-works for outgoing ones. The JUST_CFM 875 * will be converted to JUST_WORKS if necessary later in this 876 * function. If either side has MITM look up the method from the 877 * table. 878 */ 879 if (!(auth & SMP_AUTH_MITM)) 880 smp->method = JUST_CFM; 881 else 882 smp->method = get_auth_method(smp, local_io, remote_io); 883 884 /* Don't confirm locally initiated pairing attempts */ 885 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 886 &smp->flags)) 887 smp->method = JUST_WORKS; 888 889 /* Don't bother user space with no IO capabilities */ 890 if (smp->method == JUST_CFM && 891 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 892 smp->method = JUST_WORKS; 893 894 /* If Just Works, Continue with Zero TK */ 895 if (smp->method == JUST_WORKS) { 896 set_bit(SMP_FLAG_TK_VALID, &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 Keyoard-Display I/O, the master 914 * Confirms and the slave 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_DBG("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 } 947 948 static 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_DBG("conn %p", conn); 955 956 ret = smp_c1(smp->tfm_aes, 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 } 974 975 static 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 if (IS_ERR_OR_NULL(smp->tfm_aes)) 983 return SMP_UNSPECIFIED; 984 985 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 986 987 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp, 988 hcon->init_addr_type, &hcon->init_addr, 989 hcon->resp_addr_type, &hcon->resp_addr, confirm); 990 if (ret) 991 return SMP_UNSPECIFIED; 992 993 if (memcmp(smp->pcnf, confirm, sizeof(smp->pcnf)) != 0) { 994 BT_ERR("Pairing failed (confirmation values mismatch)"); 995 return SMP_CONFIRM_FAILED; 996 } 997 998 if (hcon->out) { 999 u8 stk[16]; 1000 __le64 rand = 0; 1001 __le16 ediv = 0; 1002 1003 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk); 1004 1005 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 1006 return SMP_UNSPECIFIED; 1007 1008 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 1009 hcon->enc_key_size = smp->enc_key_size; 1010 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1011 } else { 1012 u8 stk[16], auth; 1013 __le64 rand = 0; 1014 __le16 ediv = 0; 1015 1016 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1017 smp->prnd); 1018 1019 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk); 1020 1021 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1022 auth = 1; 1023 else 1024 auth = 0; 1025 1026 /* Even though there's no _SLAVE suffix this is the 1027 * slave STK we're adding for later lookup (the master 1028 * STK never needs to be stored). 1029 */ 1030 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1031 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1032 } 1033 1034 return 0; 1035 } 1036 1037 static void smp_notify_keys(struct l2cap_conn *conn) 1038 { 1039 struct l2cap_chan *chan = conn->smp; 1040 struct smp_chan *smp = chan->data; 1041 struct hci_conn *hcon = conn->hcon; 1042 struct hci_dev *hdev = hcon->hdev; 1043 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1044 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1045 bool persistent; 1046 1047 if (hcon->type == ACL_LINK) { 1048 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1049 persistent = false; 1050 else 1051 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1052 &hcon->flags); 1053 } else { 1054 /* The LTKs, IRKs and CSRKs should be persistent only if 1055 * both sides had the bonding bit set in their 1056 * authentication requests. 1057 */ 1058 persistent = !!((req->auth_req & rsp->auth_req) & 1059 SMP_AUTH_BONDING); 1060 } 1061 1062 if (smp->remote_irk) { 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->bdaddr_type = hcon->dst_type; 1078 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1079 mgmt_new_csrk(hdev, smp->csrk, persistent); 1080 } 1081 1082 if (smp->slave_csrk) { 1083 smp->slave_csrk->bdaddr_type = hcon->dst_type; 1084 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); 1085 mgmt_new_csrk(hdev, smp->slave_csrk, persistent); 1086 } 1087 1088 if (smp->ltk) { 1089 smp->ltk->bdaddr_type = hcon->dst_type; 1090 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1091 mgmt_new_ltk(hdev, smp->ltk, persistent); 1092 } 1093 1094 if (smp->slave_ltk) { 1095 smp->slave_ltk->bdaddr_type = hcon->dst_type; 1096 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); 1097 mgmt_new_ltk(hdev, smp->slave_ltk, persistent); 1098 } 1099 1100 if (smp->link_key) { 1101 struct link_key *key; 1102 u8 type; 1103 1104 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1105 type = HCI_LK_DEBUG_COMBINATION; 1106 else if (hcon->sec_level == BT_SECURITY_FIPS) 1107 type = HCI_LK_AUTH_COMBINATION_P256; 1108 else 1109 type = HCI_LK_UNAUTH_COMBINATION_P256; 1110 1111 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1112 smp->link_key, type, 0, &persistent); 1113 if (key) { 1114 mgmt_new_link_key(hdev, key, persistent); 1115 1116 /* Don't keep debug keys around if the relevant 1117 * flag is not set. 1118 */ 1119 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1120 key->type == HCI_LK_DEBUG_COMBINATION) { 1121 list_del_rcu(&key->list); 1122 kfree_rcu(key, rcu); 1123 } 1124 } 1125 } 1126 } 1127 1128 static void sc_add_ltk(struct smp_chan *smp) 1129 { 1130 struct hci_conn *hcon = smp->conn->hcon; 1131 u8 key_type, auth; 1132 1133 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1134 key_type = SMP_LTK_P256_DEBUG; 1135 else 1136 key_type = SMP_LTK_P256; 1137 1138 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1139 auth = 1; 1140 else 1141 auth = 0; 1142 1143 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1144 key_type, auth, smp->tk, smp->enc_key_size, 1145 0, 0); 1146 } 1147 1148 static void sc_generate_link_key(struct smp_chan *smp) 1149 { 1150 /* From core spec. Spells out in ASCII as 'lebr'. */ 1151 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1152 1153 smp->link_key = kzalloc(16, GFP_KERNEL); 1154 if (!smp->link_key) 1155 return; 1156 1157 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1158 /* SALT = 0x00000000000000000000000000000000746D7031 */ 1159 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1160 1161 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1162 kzfree(smp->link_key); 1163 smp->link_key = NULL; 1164 return; 1165 } 1166 } else { 1167 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1168 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1169 1170 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1171 kzfree(smp->link_key); 1172 smp->link_key = NULL; 1173 return; 1174 } 1175 } 1176 1177 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1178 kzfree(smp->link_key); 1179 smp->link_key = NULL; 1180 return; 1181 } 1182 } 1183 1184 static void smp_allow_key_dist(struct smp_chan *smp) 1185 { 1186 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1187 * will be allowed in each PDU handler to ensure we receive 1188 * them in the correct order. 1189 */ 1190 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1191 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1192 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1193 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1194 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1195 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1196 } 1197 1198 static void sc_generate_ltk(struct smp_chan *smp) 1199 { 1200 /* From core spec. Spells out in ASCII as 'brle'. */ 1201 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1202 struct hci_conn *hcon = smp->conn->hcon; 1203 struct hci_dev *hdev = hcon->hdev; 1204 struct link_key *key; 1205 1206 key = hci_find_link_key(hdev, &hcon->dst); 1207 if (!key) { 1208 BT_ERR("%s No Link Key found to generate LTK", hdev->name); 1209 return; 1210 } 1211 1212 if (key->type == HCI_LK_DEBUG_COMBINATION) 1213 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1214 1215 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1216 /* SALT = 0x00000000000000000000000000000000746D7032 */ 1217 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1218 1219 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1220 return; 1221 } else { 1222 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1223 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1224 1225 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1226 return; 1227 } 1228 1229 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1230 return; 1231 1232 sc_add_ltk(smp); 1233 } 1234 1235 static void smp_distribute_keys(struct smp_chan *smp) 1236 { 1237 struct smp_cmd_pairing *req, *rsp; 1238 struct l2cap_conn *conn = smp->conn; 1239 struct hci_conn *hcon = conn->hcon; 1240 struct hci_dev *hdev = hcon->hdev; 1241 __u8 *keydist; 1242 1243 BT_DBG("conn %p", conn); 1244 1245 rsp = (void *) &smp->prsp[1]; 1246 1247 /* The responder sends its keys first */ 1248 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1249 smp_allow_key_dist(smp); 1250 return; 1251 } 1252 1253 req = (void *) &smp->preq[1]; 1254 1255 if (hcon->out) { 1256 keydist = &rsp->init_key_dist; 1257 *keydist &= req->init_key_dist; 1258 } else { 1259 keydist = &rsp->resp_key_dist; 1260 *keydist &= req->resp_key_dist; 1261 } 1262 1263 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1264 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1265 sc_generate_link_key(smp); 1266 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1267 sc_generate_ltk(smp); 1268 1269 /* Clear the keys which are generated but not distributed */ 1270 *keydist &= ~SMP_SC_NO_DIST; 1271 } 1272 1273 BT_DBG("keydist 0x%x", *keydist); 1274 1275 if (*keydist & SMP_DIST_ENC_KEY) { 1276 struct smp_cmd_encrypt_info enc; 1277 struct smp_cmd_master_ident ident; 1278 struct smp_ltk *ltk; 1279 u8 authenticated; 1280 __le16 ediv; 1281 __le64 rand; 1282 1283 /* Make sure we generate only the significant amount of 1284 * bytes based on the encryption key size, and set the rest 1285 * of the value to zeroes. 1286 */ 1287 get_random_bytes(enc.ltk, smp->enc_key_size); 1288 memset(enc.ltk + smp->enc_key_size, 0, 1289 sizeof(enc.ltk) - smp->enc_key_size); 1290 1291 get_random_bytes(&ediv, sizeof(ediv)); 1292 get_random_bytes(&rand, sizeof(rand)); 1293 1294 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1295 1296 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1297 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1298 SMP_LTK_SLAVE, authenticated, enc.ltk, 1299 smp->enc_key_size, ediv, rand); 1300 smp->slave_ltk = ltk; 1301 1302 ident.ediv = ediv; 1303 ident.rand = rand; 1304 1305 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); 1306 1307 *keydist &= ~SMP_DIST_ENC_KEY; 1308 } 1309 1310 if (*keydist & SMP_DIST_ID_KEY) { 1311 struct smp_cmd_ident_addr_info addrinfo; 1312 struct smp_cmd_ident_info idinfo; 1313 1314 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1315 1316 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1317 1318 /* The hci_conn contains the local identity address 1319 * after the connection has been established. 1320 * 1321 * This is true even when the connection has been 1322 * established using a resolvable random address. 1323 */ 1324 bacpy(&addrinfo.bdaddr, &hcon->src); 1325 addrinfo.addr_type = hcon->src_type; 1326 1327 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1328 &addrinfo); 1329 1330 *keydist &= ~SMP_DIST_ID_KEY; 1331 } 1332 1333 if (*keydist & SMP_DIST_SIGN) { 1334 struct smp_cmd_sign_info sign; 1335 struct smp_csrk *csrk; 1336 1337 /* Generate a new random key */ 1338 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1339 1340 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1341 if (csrk) { 1342 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1343 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1344 else 1345 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1346 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1347 } 1348 smp->slave_csrk = csrk; 1349 1350 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1351 1352 *keydist &= ~SMP_DIST_SIGN; 1353 } 1354 1355 /* If there are still keys to be received wait for them */ 1356 if (smp->remote_key_dist & KEY_DIST_MASK) { 1357 smp_allow_key_dist(smp); 1358 return; 1359 } 1360 1361 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1362 smp_notify_keys(conn); 1363 1364 smp_chan_destroy(conn); 1365 } 1366 1367 static void smp_timeout(struct work_struct *work) 1368 { 1369 struct smp_chan *smp = container_of(work, struct smp_chan, 1370 security_timer.work); 1371 struct l2cap_conn *conn = smp->conn; 1372 1373 BT_DBG("conn %p", conn); 1374 1375 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1376 } 1377 1378 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1379 { 1380 struct l2cap_chan *chan = conn->smp; 1381 struct smp_chan *smp; 1382 1383 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1384 if (!smp) 1385 return NULL; 1386 1387 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 1388 if (IS_ERR(smp->tfm_aes)) { 1389 BT_ERR("Unable to create AES crypto context"); 1390 kzfree(smp); 1391 return NULL; 1392 } 1393 1394 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1395 if (IS_ERR(smp->tfm_cmac)) { 1396 BT_ERR("Unable to create CMAC crypto context"); 1397 crypto_free_cipher(smp->tfm_aes); 1398 kzfree(smp); 1399 return NULL; 1400 } 1401 1402 smp->conn = conn; 1403 chan->data = smp; 1404 1405 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1406 1407 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1408 1409 hci_conn_hold(conn->hcon); 1410 1411 return smp; 1412 } 1413 1414 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1415 { 1416 struct hci_conn *hcon = smp->conn->hcon; 1417 u8 *na, *nb, a[7], b[7]; 1418 1419 if (hcon->out) { 1420 na = smp->prnd; 1421 nb = smp->rrnd; 1422 } else { 1423 na = smp->rrnd; 1424 nb = smp->prnd; 1425 } 1426 1427 memcpy(a, &hcon->init_addr, 6); 1428 memcpy(b, &hcon->resp_addr, 6); 1429 a[6] = hcon->init_addr_type; 1430 b[6] = hcon->resp_addr_type; 1431 1432 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1433 } 1434 1435 static void sc_dhkey_check(struct smp_chan *smp) 1436 { 1437 struct hci_conn *hcon = smp->conn->hcon; 1438 struct smp_cmd_dhkey_check check; 1439 u8 a[7], b[7], *local_addr, *remote_addr; 1440 u8 io_cap[3], r[16]; 1441 1442 memcpy(a, &hcon->init_addr, 6); 1443 memcpy(b, &hcon->resp_addr, 6); 1444 a[6] = hcon->init_addr_type; 1445 b[6] = hcon->resp_addr_type; 1446 1447 if (hcon->out) { 1448 local_addr = a; 1449 remote_addr = b; 1450 memcpy(io_cap, &smp->preq[1], 3); 1451 } else { 1452 local_addr = b; 1453 remote_addr = a; 1454 memcpy(io_cap, &smp->prsp[1], 3); 1455 } 1456 1457 memset(r, 0, sizeof(r)); 1458 1459 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1460 put_unaligned_le32(hcon->passkey_notify, r); 1461 1462 if (smp->method == REQ_OOB) 1463 memcpy(r, smp->rr, 16); 1464 1465 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1466 local_addr, remote_addr, check.e); 1467 1468 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1469 } 1470 1471 static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1472 { 1473 struct l2cap_conn *conn = smp->conn; 1474 struct hci_conn *hcon = conn->hcon; 1475 struct smp_cmd_pairing_confirm cfm; 1476 u8 r; 1477 1478 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1479 r |= 0x80; 1480 1481 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1482 1483 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1484 cfm.confirm_val)) 1485 return SMP_UNSPECIFIED; 1486 1487 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1488 1489 return 0; 1490 } 1491 1492 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1493 { 1494 struct l2cap_conn *conn = smp->conn; 1495 struct hci_conn *hcon = conn->hcon; 1496 struct hci_dev *hdev = hcon->hdev; 1497 u8 cfm[16], r; 1498 1499 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1500 if (smp->passkey_round >= 20) 1501 return 0; 1502 1503 switch (smp_op) { 1504 case SMP_CMD_PAIRING_RANDOM: 1505 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1506 r |= 0x80; 1507 1508 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1509 smp->rrnd, r, cfm)) 1510 return SMP_UNSPECIFIED; 1511 1512 if (memcmp(smp->pcnf, cfm, 16)) 1513 return SMP_CONFIRM_FAILED; 1514 1515 smp->passkey_round++; 1516 1517 if (smp->passkey_round == 20) { 1518 /* Generate MacKey and LTK */ 1519 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1520 return SMP_UNSPECIFIED; 1521 } 1522 1523 /* The round is only complete when the initiator 1524 * receives pairing random. 1525 */ 1526 if (!hcon->out) { 1527 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1528 sizeof(smp->prnd), smp->prnd); 1529 if (smp->passkey_round == 20) 1530 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1531 else 1532 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1533 return 0; 1534 } 1535 1536 /* Start the next round */ 1537 if (smp->passkey_round != 20) 1538 return sc_passkey_round(smp, 0); 1539 1540 /* Passkey rounds are complete - start DHKey Check */ 1541 sc_dhkey_check(smp); 1542 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1543 1544 break; 1545 1546 case SMP_CMD_PAIRING_CONFIRM: 1547 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1548 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1549 return 0; 1550 } 1551 1552 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1553 1554 if (hcon->out) { 1555 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1556 sizeof(smp->prnd), smp->prnd); 1557 return 0; 1558 } 1559 1560 return sc_passkey_send_confirm(smp); 1561 1562 case SMP_CMD_PUBLIC_KEY: 1563 default: 1564 /* Initiating device starts the round */ 1565 if (!hcon->out) 1566 return 0; 1567 1568 BT_DBG("%s Starting passkey round %u", hdev->name, 1569 smp->passkey_round + 1); 1570 1571 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1572 1573 return sc_passkey_send_confirm(smp); 1574 } 1575 1576 return 0; 1577 } 1578 1579 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1580 { 1581 struct l2cap_conn *conn = smp->conn; 1582 struct hci_conn *hcon = conn->hcon; 1583 u8 smp_op; 1584 1585 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1586 1587 switch (mgmt_op) { 1588 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1589 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1590 return 0; 1591 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1592 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1593 return 0; 1594 case MGMT_OP_USER_PASSKEY_REPLY: 1595 hcon->passkey_notify = le32_to_cpu(passkey); 1596 smp->passkey_round = 0; 1597 1598 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1599 smp_op = SMP_CMD_PAIRING_CONFIRM; 1600 else 1601 smp_op = 0; 1602 1603 if (sc_passkey_round(smp, smp_op)) 1604 return -EIO; 1605 1606 return 0; 1607 } 1608 1609 /* Initiator sends DHKey check first */ 1610 if (hcon->out) { 1611 sc_dhkey_check(smp); 1612 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1613 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1614 sc_dhkey_check(smp); 1615 sc_add_ltk(smp); 1616 } 1617 1618 return 0; 1619 } 1620 1621 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1622 { 1623 struct l2cap_conn *conn = hcon->l2cap_data; 1624 struct l2cap_chan *chan; 1625 struct smp_chan *smp; 1626 u32 value; 1627 int err; 1628 1629 BT_DBG(""); 1630 1631 if (!conn) 1632 return -ENOTCONN; 1633 1634 chan = conn->smp; 1635 if (!chan) 1636 return -ENOTCONN; 1637 1638 l2cap_chan_lock(chan); 1639 if (!chan->data) { 1640 err = -ENOTCONN; 1641 goto unlock; 1642 } 1643 1644 smp = chan->data; 1645 1646 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1647 err = sc_user_reply(smp, mgmt_op, passkey); 1648 goto unlock; 1649 } 1650 1651 switch (mgmt_op) { 1652 case MGMT_OP_USER_PASSKEY_REPLY: 1653 value = le32_to_cpu(passkey); 1654 memset(smp->tk, 0, sizeof(smp->tk)); 1655 BT_DBG("PassKey: %d", value); 1656 put_unaligned_le32(value, smp->tk); 1657 /* Fall Through */ 1658 case MGMT_OP_USER_CONFIRM_REPLY: 1659 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1660 break; 1661 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1662 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1663 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1664 err = 0; 1665 goto unlock; 1666 default: 1667 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1668 err = -EOPNOTSUPP; 1669 goto unlock; 1670 } 1671 1672 err = 0; 1673 1674 /* If it is our turn to send Pairing Confirm, do so now */ 1675 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1676 u8 rsp = smp_confirm(smp); 1677 if (rsp) 1678 smp_failure(conn, rsp); 1679 } 1680 1681 unlock: 1682 l2cap_chan_unlock(chan); 1683 return err; 1684 } 1685 1686 static void build_bredr_pairing_cmd(struct smp_chan *smp, 1687 struct smp_cmd_pairing *req, 1688 struct smp_cmd_pairing *rsp) 1689 { 1690 struct l2cap_conn *conn = smp->conn; 1691 struct hci_dev *hdev = conn->hcon->hdev; 1692 u8 local_dist = 0, remote_dist = 0; 1693 1694 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1695 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1696 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1697 } 1698 1699 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1700 remote_dist |= SMP_DIST_ID_KEY; 1701 1702 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1703 local_dist |= SMP_DIST_ID_KEY; 1704 1705 if (!rsp) { 1706 memset(req, 0, sizeof(*req)); 1707 1708 req->auth_req = SMP_AUTH_CT2; 1709 req->init_key_dist = local_dist; 1710 req->resp_key_dist = remote_dist; 1711 req->max_key_size = conn->hcon->enc_key_size; 1712 1713 smp->remote_key_dist = remote_dist; 1714 1715 return; 1716 } 1717 1718 memset(rsp, 0, sizeof(*rsp)); 1719 1720 rsp->auth_req = SMP_AUTH_CT2; 1721 rsp->max_key_size = conn->hcon->enc_key_size; 1722 rsp->init_key_dist = req->init_key_dist & remote_dist; 1723 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1724 1725 smp->remote_key_dist = rsp->init_key_dist; 1726 } 1727 1728 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1729 { 1730 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1731 struct l2cap_chan *chan = conn->smp; 1732 struct hci_dev *hdev = conn->hcon->hdev; 1733 struct smp_chan *smp; 1734 u8 key_size, auth, sec_level; 1735 int ret; 1736 1737 BT_DBG("conn %p", conn); 1738 1739 if (skb->len < sizeof(*req)) 1740 return SMP_INVALID_PARAMS; 1741 1742 if (conn->hcon->role != HCI_ROLE_SLAVE) 1743 return SMP_CMD_NOTSUPP; 1744 1745 if (!chan->data) 1746 smp = smp_chan_create(conn); 1747 else 1748 smp = chan->data; 1749 1750 if (!smp) 1751 return SMP_UNSPECIFIED; 1752 1753 /* We didn't start the pairing, so match remote */ 1754 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1755 1756 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1757 (auth & SMP_AUTH_BONDING)) 1758 return SMP_PAIRING_NOTSUPP; 1759 1760 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1761 return SMP_AUTH_REQUIREMENTS; 1762 1763 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1764 memcpy(&smp->preq[1], req, sizeof(*req)); 1765 skb_pull(skb, sizeof(*req)); 1766 1767 /* If the remote side's OOB flag is set it means it has 1768 * successfully received our local OOB data - therefore set the 1769 * flag to indicate that local OOB is in use. 1770 */ 1771 if (req->oob_flag == SMP_OOB_PRESENT) 1772 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1773 1774 /* SMP over BR/EDR requires special treatment */ 1775 if (conn->hcon->type == ACL_LINK) { 1776 /* We must have a BR/EDR SC link */ 1777 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1778 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1779 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1780 1781 set_bit(SMP_FLAG_SC, &smp->flags); 1782 1783 build_bredr_pairing_cmd(smp, req, &rsp); 1784 1785 if (req->auth_req & SMP_AUTH_CT2) 1786 set_bit(SMP_FLAG_CT2, &smp->flags); 1787 1788 key_size = min(req->max_key_size, rsp.max_key_size); 1789 if (check_enc_key_size(conn, key_size)) 1790 return SMP_ENC_KEY_SIZE; 1791 1792 /* Clear bits which are generated but not distributed */ 1793 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1794 1795 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1796 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1797 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1798 1799 smp_distribute_keys(smp); 1800 return 0; 1801 } 1802 1803 build_pairing_cmd(conn, req, &rsp, auth); 1804 1805 if (rsp.auth_req & SMP_AUTH_SC) { 1806 set_bit(SMP_FLAG_SC, &smp->flags); 1807 1808 if (rsp.auth_req & SMP_AUTH_CT2) 1809 set_bit(SMP_FLAG_CT2, &smp->flags); 1810 } 1811 1812 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1813 sec_level = BT_SECURITY_MEDIUM; 1814 else 1815 sec_level = authreq_to_seclevel(auth); 1816 1817 if (sec_level > conn->hcon->pending_sec_level) 1818 conn->hcon->pending_sec_level = sec_level; 1819 1820 /* If we need MITM check that it can be achieved */ 1821 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1822 u8 method; 1823 1824 method = get_auth_method(smp, conn->hcon->io_capability, 1825 req->io_capability); 1826 if (method == JUST_WORKS || method == JUST_CFM) 1827 return SMP_AUTH_REQUIREMENTS; 1828 } 1829 1830 key_size = min(req->max_key_size, rsp.max_key_size); 1831 if (check_enc_key_size(conn, key_size)) 1832 return SMP_ENC_KEY_SIZE; 1833 1834 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1835 1836 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1837 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1838 1839 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1840 1841 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1842 1843 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1844 * SC case, however some implementations incorrectly copy RFU auth 1845 * req bits from our security request, which may create a false 1846 * positive SC enablement. 1847 */ 1848 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1849 1850 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1851 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1852 /* Clear bits which are generated but not distributed */ 1853 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1854 /* Wait for Public Key from Initiating Device */ 1855 return 0; 1856 } 1857 1858 /* Request setup of TK */ 1859 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1860 if (ret) 1861 return SMP_UNSPECIFIED; 1862 1863 return 0; 1864 } 1865 1866 static u8 sc_send_public_key(struct smp_chan *smp) 1867 { 1868 struct hci_dev *hdev = smp->conn->hcon->hdev; 1869 1870 BT_DBG(""); 1871 1872 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1873 struct l2cap_chan *chan = hdev->smp_data; 1874 struct smp_dev *smp_dev; 1875 1876 if (!chan || !chan->data) 1877 return SMP_UNSPECIFIED; 1878 1879 smp_dev = chan->data; 1880 1881 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1882 memcpy(smp->local_sk, smp_dev->local_sk, 32); 1883 memcpy(smp->lr, smp_dev->local_rand, 16); 1884 1885 if (smp_dev->debug_key) 1886 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1887 1888 goto done; 1889 } 1890 1891 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1892 BT_DBG("Using debug keys"); 1893 memcpy(smp->local_pk, debug_pk, 64); 1894 memcpy(smp->local_sk, debug_sk, 32); 1895 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1896 } else { 1897 while (true) { 1898 /* Generate local key pair for Secure Connections */ 1899 if (!ecc_make_key(smp->local_pk, smp->local_sk)) 1900 return SMP_UNSPECIFIED; 1901 1902 /* This is unlikely, but we need to check that 1903 * we didn't accidentially generate a debug key. 1904 */ 1905 if (memcmp(smp->local_sk, debug_sk, 32)) 1906 break; 1907 } 1908 } 1909 1910 done: 1911 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1912 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1913 SMP_DBG("Local Private Key: %32phN", smp->local_sk); 1914 1915 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1916 1917 return 0; 1918 } 1919 1920 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1921 { 1922 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1923 struct l2cap_chan *chan = conn->smp; 1924 struct smp_chan *smp = chan->data; 1925 struct hci_dev *hdev = conn->hcon->hdev; 1926 u8 key_size, auth; 1927 int ret; 1928 1929 BT_DBG("conn %p", conn); 1930 1931 if (skb->len < sizeof(*rsp)) 1932 return SMP_INVALID_PARAMS; 1933 1934 if (conn->hcon->role != HCI_ROLE_MASTER) 1935 return SMP_CMD_NOTSUPP; 1936 1937 skb_pull(skb, sizeof(*rsp)); 1938 1939 req = (void *) &smp->preq[1]; 1940 1941 key_size = min(req->max_key_size, rsp->max_key_size); 1942 if (check_enc_key_size(conn, key_size)) 1943 return SMP_ENC_KEY_SIZE; 1944 1945 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1946 1947 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1948 return SMP_AUTH_REQUIREMENTS; 1949 1950 /* If the remote side's OOB flag is set it means it has 1951 * successfully received our local OOB data - therefore set the 1952 * flag to indicate that local OOB is in use. 1953 */ 1954 if (rsp->oob_flag == SMP_OOB_PRESENT) 1955 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1956 1957 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1958 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1959 1960 /* Update remote key distribution in case the remote cleared 1961 * some bits that we had enabled in our request. 1962 */ 1963 smp->remote_key_dist &= rsp->resp_key_dist; 1964 1965 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1966 set_bit(SMP_FLAG_CT2, &smp->flags); 1967 1968 /* For BR/EDR this means we're done and can start phase 3 */ 1969 if (conn->hcon->type == ACL_LINK) { 1970 /* Clear bits which are generated but not distributed */ 1971 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1972 smp_distribute_keys(smp); 1973 return 0; 1974 } 1975 1976 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1977 set_bit(SMP_FLAG_SC, &smp->flags); 1978 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1979 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1980 1981 /* If we need MITM check that it can be achieved */ 1982 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1983 u8 method; 1984 1985 method = get_auth_method(smp, req->io_capability, 1986 rsp->io_capability); 1987 if (method == JUST_WORKS || method == JUST_CFM) 1988 return SMP_AUTH_REQUIREMENTS; 1989 } 1990 1991 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1992 1993 /* Update remote key distribution in case the remote cleared 1994 * some bits that we had enabled in our request. 1995 */ 1996 smp->remote_key_dist &= rsp->resp_key_dist; 1997 1998 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1999 /* Clear bits which are generated but not distributed */ 2000 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 2001 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 2002 return sc_send_public_key(smp); 2003 } 2004 2005 auth |= req->auth_req; 2006 2007 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2008 if (ret) 2009 return SMP_UNSPECIFIED; 2010 2011 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2012 2013 /* Can't compose response until we have been confirmed */ 2014 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2015 return smp_confirm(smp); 2016 2017 return 0; 2018 } 2019 2020 static u8 sc_check_confirm(struct smp_chan *smp) 2021 { 2022 struct l2cap_conn *conn = smp->conn; 2023 2024 BT_DBG(""); 2025 2026 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2027 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2028 2029 if (conn->hcon->out) { 2030 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2031 smp->prnd); 2032 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2033 } 2034 2035 return 0; 2036 } 2037 2038 /* Work-around for some implementations that incorrectly copy RFU bits 2039 * from our security request and thereby create the impression that 2040 * we're doing SC when in fact the remote doesn't support it. 2041 */ 2042 static int fixup_sc_false_positive(struct smp_chan *smp) 2043 { 2044 struct l2cap_conn *conn = smp->conn; 2045 struct hci_conn *hcon = conn->hcon; 2046 struct hci_dev *hdev = hcon->hdev; 2047 struct smp_cmd_pairing *req, *rsp; 2048 u8 auth; 2049 2050 /* The issue is only observed when we're in slave role */ 2051 if (hcon->out) 2052 return SMP_UNSPECIFIED; 2053 2054 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2055 BT_ERR("Refusing SMP SC -> legacy fallback in SC-only mode"); 2056 return SMP_UNSPECIFIED; 2057 } 2058 2059 BT_ERR("Trying to fall back to legacy SMP"); 2060 2061 req = (void *) &smp->preq[1]; 2062 rsp = (void *) &smp->prsp[1]; 2063 2064 /* Rebuild key dist flags which may have been cleared for SC */ 2065 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2066 2067 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2068 2069 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2070 BT_ERR("Failed to fall back to legacy SMP"); 2071 return SMP_UNSPECIFIED; 2072 } 2073 2074 clear_bit(SMP_FLAG_SC, &smp->flags); 2075 2076 return 0; 2077 } 2078 2079 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2080 { 2081 struct l2cap_chan *chan = conn->smp; 2082 struct smp_chan *smp = chan->data; 2083 2084 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 2085 2086 if (skb->len < sizeof(smp->pcnf)) 2087 return SMP_INVALID_PARAMS; 2088 2089 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2090 skb_pull(skb, sizeof(smp->pcnf)); 2091 2092 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2093 int ret; 2094 2095 /* Public Key exchange must happen before any other steps */ 2096 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2097 return sc_check_confirm(smp); 2098 2099 BT_ERR("Unexpected SMP Pairing Confirm"); 2100 2101 ret = fixup_sc_false_positive(smp); 2102 if (ret) 2103 return ret; 2104 } 2105 2106 if (conn->hcon->out) { 2107 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2108 smp->prnd); 2109 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2110 return 0; 2111 } 2112 2113 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2114 return smp_confirm(smp); 2115 2116 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2117 2118 return 0; 2119 } 2120 2121 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2122 { 2123 struct l2cap_chan *chan = conn->smp; 2124 struct smp_chan *smp = chan->data; 2125 struct hci_conn *hcon = conn->hcon; 2126 u8 *pkax, *pkbx, *na, *nb; 2127 u32 passkey; 2128 int err; 2129 2130 BT_DBG("conn %p", conn); 2131 2132 if (skb->len < sizeof(smp->rrnd)) 2133 return SMP_INVALID_PARAMS; 2134 2135 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2136 skb_pull(skb, sizeof(smp->rrnd)); 2137 2138 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2139 return smp_random(smp); 2140 2141 if (hcon->out) { 2142 pkax = smp->local_pk; 2143 pkbx = smp->remote_pk; 2144 na = smp->prnd; 2145 nb = smp->rrnd; 2146 } else { 2147 pkax = smp->remote_pk; 2148 pkbx = smp->local_pk; 2149 na = smp->rrnd; 2150 nb = smp->prnd; 2151 } 2152 2153 if (smp->method == REQ_OOB) { 2154 if (!hcon->out) 2155 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2156 sizeof(smp->prnd), smp->prnd); 2157 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2158 goto mackey_and_ltk; 2159 } 2160 2161 /* Passkey entry has special treatment */ 2162 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2163 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2164 2165 if (hcon->out) { 2166 u8 cfm[16]; 2167 2168 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2169 smp->rrnd, 0, cfm); 2170 if (err) 2171 return SMP_UNSPECIFIED; 2172 2173 if (memcmp(smp->pcnf, cfm, 16)) 2174 return SMP_CONFIRM_FAILED; 2175 } else { 2176 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2177 smp->prnd); 2178 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2179 } 2180 2181 mackey_and_ltk: 2182 /* Generate MacKey and LTK */ 2183 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); 2184 if (err) 2185 return SMP_UNSPECIFIED; 2186 2187 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) { 2188 if (hcon->out) { 2189 sc_dhkey_check(smp); 2190 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2191 } 2192 return 0; 2193 } 2194 2195 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); 2196 if (err) 2197 return SMP_UNSPECIFIED; 2198 2199 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2200 hcon->dst_type, passkey, 0); 2201 if (err) 2202 return SMP_UNSPECIFIED; 2203 2204 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2205 2206 return 0; 2207 } 2208 2209 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2210 { 2211 struct smp_ltk *key; 2212 struct hci_conn *hcon = conn->hcon; 2213 2214 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2215 if (!key) 2216 return false; 2217 2218 if (smp_ltk_sec_level(key) < sec_level) 2219 return false; 2220 2221 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2222 return true; 2223 2224 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2225 hcon->enc_key_size = key->enc_size; 2226 2227 /* We never store STKs for master role, so clear this flag */ 2228 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2229 2230 return true; 2231 } 2232 2233 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2234 enum smp_key_pref key_pref) 2235 { 2236 if (sec_level == BT_SECURITY_LOW) 2237 return true; 2238 2239 /* If we're encrypted with an STK but the caller prefers using 2240 * LTK claim insufficient security. This way we allow the 2241 * connection to be re-encrypted with an LTK, even if the LTK 2242 * provides the same level of security. Only exception is if we 2243 * don't have an LTK (e.g. because of key distribution bits). 2244 */ 2245 if (key_pref == SMP_USE_LTK && 2246 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2247 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2248 return false; 2249 2250 if (hcon->sec_level >= sec_level) 2251 return true; 2252 2253 return false; 2254 } 2255 2256 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2257 { 2258 struct smp_cmd_security_req *rp = (void *) skb->data; 2259 struct smp_cmd_pairing cp; 2260 struct hci_conn *hcon = conn->hcon; 2261 struct hci_dev *hdev = hcon->hdev; 2262 struct smp_chan *smp; 2263 u8 sec_level, auth; 2264 2265 BT_DBG("conn %p", conn); 2266 2267 if (skb->len < sizeof(*rp)) 2268 return SMP_INVALID_PARAMS; 2269 2270 if (hcon->role != HCI_ROLE_MASTER) 2271 return SMP_CMD_NOTSUPP; 2272 2273 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2274 2275 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2276 return SMP_AUTH_REQUIREMENTS; 2277 2278 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2279 sec_level = BT_SECURITY_MEDIUM; 2280 else 2281 sec_level = authreq_to_seclevel(auth); 2282 2283 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2284 return 0; 2285 2286 if (sec_level > hcon->pending_sec_level) 2287 hcon->pending_sec_level = sec_level; 2288 2289 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2290 return 0; 2291 2292 smp = smp_chan_create(conn); 2293 if (!smp) 2294 return SMP_UNSPECIFIED; 2295 2296 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2297 (auth & SMP_AUTH_BONDING)) 2298 return SMP_PAIRING_NOTSUPP; 2299 2300 skb_pull(skb, sizeof(*rp)); 2301 2302 memset(&cp, 0, sizeof(cp)); 2303 build_pairing_cmd(conn, &cp, NULL, auth); 2304 2305 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2306 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2307 2308 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2309 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2310 2311 return 0; 2312 } 2313 2314 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2315 { 2316 struct l2cap_conn *conn = hcon->l2cap_data; 2317 struct l2cap_chan *chan; 2318 struct smp_chan *smp; 2319 __u8 authreq; 2320 int ret; 2321 2322 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); 2323 2324 /* This may be NULL if there's an unexpected disconnection */ 2325 if (!conn) 2326 return 1; 2327 2328 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2329 return 1; 2330 2331 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2332 return 1; 2333 2334 if (sec_level > hcon->pending_sec_level) 2335 hcon->pending_sec_level = sec_level; 2336 2337 if (hcon->role == HCI_ROLE_MASTER) 2338 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2339 return 0; 2340 2341 chan = conn->smp; 2342 if (!chan) { 2343 BT_ERR("SMP security requested but not available"); 2344 return 1; 2345 } 2346 2347 l2cap_chan_lock(chan); 2348 2349 /* If SMP is already in progress ignore this request */ 2350 if (chan->data) { 2351 ret = 0; 2352 goto unlock; 2353 } 2354 2355 smp = smp_chan_create(conn); 2356 if (!smp) { 2357 ret = 1; 2358 goto unlock; 2359 } 2360 2361 authreq = seclevel_to_authreq(sec_level); 2362 2363 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2364 authreq |= SMP_AUTH_SC; 2365 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2366 authreq |= SMP_AUTH_CT2; 2367 } 2368 2369 /* Require MITM if IO Capability allows or the security level 2370 * requires it. 2371 */ 2372 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2373 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2374 authreq |= SMP_AUTH_MITM; 2375 2376 if (hcon->role == HCI_ROLE_MASTER) { 2377 struct smp_cmd_pairing cp; 2378 2379 build_pairing_cmd(conn, &cp, NULL, authreq); 2380 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2381 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2382 2383 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2384 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2385 } else { 2386 struct smp_cmd_security_req cp; 2387 cp.auth_req = authreq; 2388 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2389 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2390 } 2391 2392 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2393 ret = 0; 2394 2395 unlock: 2396 l2cap_chan_unlock(chan); 2397 return ret; 2398 } 2399 2400 void smp_cancel_pairing(struct hci_conn *hcon) 2401 { 2402 struct l2cap_conn *conn = hcon->l2cap_data; 2403 struct l2cap_chan *chan; 2404 struct smp_chan *smp; 2405 2406 if (!conn) 2407 return; 2408 2409 chan = conn->smp; 2410 if (!chan) 2411 return; 2412 2413 l2cap_chan_lock(chan); 2414 2415 smp = chan->data; 2416 if (smp) { 2417 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2418 smp_failure(conn, 0); 2419 else 2420 smp_failure(conn, SMP_UNSPECIFIED); 2421 } 2422 2423 l2cap_chan_unlock(chan); 2424 } 2425 2426 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2427 { 2428 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2429 struct l2cap_chan *chan = conn->smp; 2430 struct smp_chan *smp = chan->data; 2431 2432 BT_DBG("conn %p", conn); 2433 2434 if (skb->len < sizeof(*rp)) 2435 return SMP_INVALID_PARAMS; 2436 2437 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); 2438 2439 skb_pull(skb, sizeof(*rp)); 2440 2441 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2442 2443 return 0; 2444 } 2445 2446 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2447 { 2448 struct smp_cmd_master_ident *rp = (void *) skb->data; 2449 struct l2cap_chan *chan = conn->smp; 2450 struct smp_chan *smp = chan->data; 2451 struct hci_dev *hdev = conn->hcon->hdev; 2452 struct hci_conn *hcon = conn->hcon; 2453 struct smp_ltk *ltk; 2454 u8 authenticated; 2455 2456 BT_DBG("conn %p", conn); 2457 2458 if (skb->len < sizeof(*rp)) 2459 return SMP_INVALID_PARAMS; 2460 2461 /* Mark the information as received */ 2462 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2463 2464 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2465 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2466 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2467 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2468 2469 skb_pull(skb, sizeof(*rp)); 2470 2471 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2472 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2473 authenticated, smp->tk, smp->enc_key_size, 2474 rp->ediv, rp->rand); 2475 smp->ltk = ltk; 2476 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2477 smp_distribute_keys(smp); 2478 2479 return 0; 2480 } 2481 2482 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2483 { 2484 struct smp_cmd_ident_info *info = (void *) skb->data; 2485 struct l2cap_chan *chan = conn->smp; 2486 struct smp_chan *smp = chan->data; 2487 2488 BT_DBG(""); 2489 2490 if (skb->len < sizeof(*info)) 2491 return SMP_INVALID_PARAMS; 2492 2493 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2494 2495 skb_pull(skb, sizeof(*info)); 2496 2497 memcpy(smp->irk, info->irk, 16); 2498 2499 return 0; 2500 } 2501 2502 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2503 struct sk_buff *skb) 2504 { 2505 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2506 struct l2cap_chan *chan = conn->smp; 2507 struct smp_chan *smp = chan->data; 2508 struct hci_conn *hcon = conn->hcon; 2509 bdaddr_t rpa; 2510 2511 BT_DBG(""); 2512 2513 if (skb->len < sizeof(*info)) 2514 return SMP_INVALID_PARAMS; 2515 2516 /* Mark the information as received */ 2517 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2518 2519 if (smp->remote_key_dist & SMP_DIST_SIGN) 2520 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2521 2522 skb_pull(skb, sizeof(*info)); 2523 2524 /* Strictly speaking the Core Specification (4.1) allows sending 2525 * an empty address which would force us to rely on just the IRK 2526 * as "identity information". However, since such 2527 * implementations are not known of and in order to not over 2528 * complicate our implementation, simply pretend that we never 2529 * received an IRK for such a device. 2530 * 2531 * The Identity Address must also be a Static Random or Public 2532 * Address, which hci_is_identity_address() checks for. 2533 */ 2534 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2535 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2536 BT_ERR("Ignoring IRK with no identity address"); 2537 goto distribute; 2538 } 2539 2540 bacpy(&smp->id_addr, &info->bdaddr); 2541 smp->id_addr_type = info->addr_type; 2542 2543 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2544 bacpy(&rpa, &hcon->dst); 2545 else 2546 bacpy(&rpa, BDADDR_ANY); 2547 2548 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2549 smp->id_addr_type, smp->irk, &rpa); 2550 2551 distribute: 2552 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2553 smp_distribute_keys(smp); 2554 2555 return 0; 2556 } 2557 2558 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2559 { 2560 struct smp_cmd_sign_info *rp = (void *) skb->data; 2561 struct l2cap_chan *chan = conn->smp; 2562 struct smp_chan *smp = chan->data; 2563 struct smp_csrk *csrk; 2564 2565 BT_DBG("conn %p", conn); 2566 2567 if (skb->len < sizeof(*rp)) 2568 return SMP_INVALID_PARAMS; 2569 2570 /* Mark the information as received */ 2571 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2572 2573 skb_pull(skb, sizeof(*rp)); 2574 2575 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2576 if (csrk) { 2577 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2578 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2579 else 2580 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2581 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2582 } 2583 smp->csrk = csrk; 2584 smp_distribute_keys(smp); 2585 2586 return 0; 2587 } 2588 2589 static u8 sc_select_method(struct smp_chan *smp) 2590 { 2591 struct l2cap_conn *conn = smp->conn; 2592 struct hci_conn *hcon = conn->hcon; 2593 struct smp_cmd_pairing *local, *remote; 2594 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2595 2596 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2597 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2598 return REQ_OOB; 2599 2600 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2601 * which are needed as inputs to some crypto functions. To get 2602 * the "struct smp_cmd_pairing" from them we need to skip the 2603 * first byte which contains the opcode. 2604 */ 2605 if (hcon->out) { 2606 local = (void *) &smp->preq[1]; 2607 remote = (void *) &smp->prsp[1]; 2608 } else { 2609 local = (void *) &smp->prsp[1]; 2610 remote = (void *) &smp->preq[1]; 2611 } 2612 2613 local_io = local->io_capability; 2614 remote_io = remote->io_capability; 2615 2616 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2617 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2618 2619 /* If either side wants MITM, look up the method from the table, 2620 * otherwise use JUST WORKS. 2621 */ 2622 if (local_mitm || remote_mitm) 2623 method = get_auth_method(smp, local_io, remote_io); 2624 else 2625 method = JUST_WORKS; 2626 2627 /* Don't confirm locally initiated pairing attempts */ 2628 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2629 method = JUST_WORKS; 2630 2631 return method; 2632 } 2633 2634 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2635 { 2636 struct smp_cmd_public_key *key = (void *) skb->data; 2637 struct hci_conn *hcon = conn->hcon; 2638 struct l2cap_chan *chan = conn->smp; 2639 struct smp_chan *smp = chan->data; 2640 struct hci_dev *hdev = hcon->hdev; 2641 struct smp_cmd_pairing_confirm cfm; 2642 int err; 2643 2644 BT_DBG("conn %p", conn); 2645 2646 if (skb->len < sizeof(*key)) 2647 return SMP_INVALID_PARAMS; 2648 2649 memcpy(smp->remote_pk, key, 64); 2650 2651 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2652 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2653 smp->rr, 0, cfm.confirm_val); 2654 if (err) 2655 return SMP_UNSPECIFIED; 2656 2657 if (memcmp(cfm.confirm_val, smp->pcnf, 16)) 2658 return SMP_CONFIRM_FAILED; 2659 } 2660 2661 /* Non-initiating device sends its public key after receiving 2662 * the key from the initiating device. 2663 */ 2664 if (!hcon->out) { 2665 err = sc_send_public_key(smp); 2666 if (err) 2667 return err; 2668 } 2669 2670 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2671 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2672 2673 if (!ecdh_shared_secret(smp->remote_pk, smp->local_sk, smp->dhkey)) 2674 return SMP_UNSPECIFIED; 2675 2676 SMP_DBG("DHKey %32phN", smp->dhkey); 2677 2678 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2679 2680 smp->method = sc_select_method(smp); 2681 2682 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method); 2683 2684 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2685 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2686 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2687 else 2688 hcon->pending_sec_level = BT_SECURITY_FIPS; 2689 2690 if (!memcmp(debug_pk, smp->remote_pk, 64)) 2691 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2692 2693 if (smp->method == DSP_PASSKEY) { 2694 get_random_bytes(&hcon->passkey_notify, 2695 sizeof(hcon->passkey_notify)); 2696 hcon->passkey_notify %= 1000000; 2697 hcon->passkey_entered = 0; 2698 smp->passkey_round = 0; 2699 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2700 hcon->dst_type, 2701 hcon->passkey_notify, 2702 hcon->passkey_entered)) 2703 return SMP_UNSPECIFIED; 2704 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2705 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2706 } 2707 2708 if (smp->method == REQ_OOB) { 2709 if (hcon->out) 2710 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2711 sizeof(smp->prnd), smp->prnd); 2712 2713 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2714 2715 return 0; 2716 } 2717 2718 if (hcon->out) 2719 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2720 2721 if (smp->method == REQ_PASSKEY) { 2722 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2723 hcon->dst_type)) 2724 return SMP_UNSPECIFIED; 2725 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2726 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2727 return 0; 2728 } 2729 2730 /* The Initiating device waits for the non-initiating device to 2731 * send the confirm value. 2732 */ 2733 if (conn->hcon->out) 2734 return 0; 2735 2736 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2737 0, cfm.confirm_val); 2738 if (err) 2739 return SMP_UNSPECIFIED; 2740 2741 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2742 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2743 2744 return 0; 2745 } 2746 2747 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2748 { 2749 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2750 struct l2cap_chan *chan = conn->smp; 2751 struct hci_conn *hcon = conn->hcon; 2752 struct smp_chan *smp = chan->data; 2753 u8 a[7], b[7], *local_addr, *remote_addr; 2754 u8 io_cap[3], r[16], e[16]; 2755 int err; 2756 2757 BT_DBG("conn %p", conn); 2758 2759 if (skb->len < sizeof(*check)) 2760 return SMP_INVALID_PARAMS; 2761 2762 memcpy(a, &hcon->init_addr, 6); 2763 memcpy(b, &hcon->resp_addr, 6); 2764 a[6] = hcon->init_addr_type; 2765 b[6] = hcon->resp_addr_type; 2766 2767 if (hcon->out) { 2768 local_addr = a; 2769 remote_addr = b; 2770 memcpy(io_cap, &smp->prsp[1], 3); 2771 } else { 2772 local_addr = b; 2773 remote_addr = a; 2774 memcpy(io_cap, &smp->preq[1], 3); 2775 } 2776 2777 memset(r, 0, sizeof(r)); 2778 2779 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2780 put_unaligned_le32(hcon->passkey_notify, r); 2781 else if (smp->method == REQ_OOB) 2782 memcpy(r, smp->lr, 16); 2783 2784 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2785 io_cap, remote_addr, local_addr, e); 2786 if (err) 2787 return SMP_UNSPECIFIED; 2788 2789 if (memcmp(check->e, e, 16)) 2790 return SMP_DHKEY_CHECK_FAILED; 2791 2792 if (!hcon->out) { 2793 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2794 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2795 return 0; 2796 } 2797 2798 /* Slave sends DHKey check as response to master */ 2799 sc_dhkey_check(smp); 2800 } 2801 2802 sc_add_ltk(smp); 2803 2804 if (hcon->out) { 2805 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2806 hcon->enc_key_size = smp->enc_key_size; 2807 } 2808 2809 return 0; 2810 } 2811 2812 static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2813 struct sk_buff *skb) 2814 { 2815 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2816 2817 BT_DBG("value 0x%02x", kp->value); 2818 2819 return 0; 2820 } 2821 2822 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2823 { 2824 struct l2cap_conn *conn = chan->conn; 2825 struct hci_conn *hcon = conn->hcon; 2826 struct smp_chan *smp; 2827 __u8 code, reason; 2828 int err = 0; 2829 2830 if (skb->len < 1) 2831 return -EILSEQ; 2832 2833 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2834 reason = SMP_PAIRING_NOTSUPP; 2835 goto done; 2836 } 2837 2838 code = skb->data[0]; 2839 skb_pull(skb, sizeof(code)); 2840 2841 smp = chan->data; 2842 2843 if (code > SMP_CMD_MAX) 2844 goto drop; 2845 2846 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2847 goto drop; 2848 2849 /* If we don't have a context the only allowed commands are 2850 * pairing request and security request. 2851 */ 2852 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2853 goto drop; 2854 2855 switch (code) { 2856 case SMP_CMD_PAIRING_REQ: 2857 reason = smp_cmd_pairing_req(conn, skb); 2858 break; 2859 2860 case SMP_CMD_PAIRING_FAIL: 2861 smp_failure(conn, 0); 2862 err = -EPERM; 2863 break; 2864 2865 case SMP_CMD_PAIRING_RSP: 2866 reason = smp_cmd_pairing_rsp(conn, skb); 2867 break; 2868 2869 case SMP_CMD_SECURITY_REQ: 2870 reason = smp_cmd_security_req(conn, skb); 2871 break; 2872 2873 case SMP_CMD_PAIRING_CONFIRM: 2874 reason = smp_cmd_pairing_confirm(conn, skb); 2875 break; 2876 2877 case SMP_CMD_PAIRING_RANDOM: 2878 reason = smp_cmd_pairing_random(conn, skb); 2879 break; 2880 2881 case SMP_CMD_ENCRYPT_INFO: 2882 reason = smp_cmd_encrypt_info(conn, skb); 2883 break; 2884 2885 case SMP_CMD_MASTER_IDENT: 2886 reason = smp_cmd_master_ident(conn, skb); 2887 break; 2888 2889 case SMP_CMD_IDENT_INFO: 2890 reason = smp_cmd_ident_info(conn, skb); 2891 break; 2892 2893 case SMP_CMD_IDENT_ADDR_INFO: 2894 reason = smp_cmd_ident_addr_info(conn, skb); 2895 break; 2896 2897 case SMP_CMD_SIGN_INFO: 2898 reason = smp_cmd_sign_info(conn, skb); 2899 break; 2900 2901 case SMP_CMD_PUBLIC_KEY: 2902 reason = smp_cmd_public_key(conn, skb); 2903 break; 2904 2905 case SMP_CMD_DHKEY_CHECK: 2906 reason = smp_cmd_dhkey_check(conn, skb); 2907 break; 2908 2909 case SMP_CMD_KEYPRESS_NOTIFY: 2910 reason = smp_cmd_keypress_notify(conn, skb); 2911 break; 2912 2913 default: 2914 BT_DBG("Unknown command code 0x%2.2x", code); 2915 reason = SMP_CMD_NOTSUPP; 2916 goto done; 2917 } 2918 2919 done: 2920 if (!err) { 2921 if (reason) 2922 smp_failure(conn, reason); 2923 kfree_skb(skb); 2924 } 2925 2926 return err; 2927 2928 drop: 2929 BT_ERR("%s unexpected SMP command 0x%02x from %pMR", hcon->hdev->name, 2930 code, &hcon->dst); 2931 kfree_skb(skb); 2932 return 0; 2933 } 2934 2935 static void smp_teardown_cb(struct l2cap_chan *chan, int err) 2936 { 2937 struct l2cap_conn *conn = chan->conn; 2938 2939 BT_DBG("chan %p", chan); 2940 2941 if (chan->data) 2942 smp_chan_destroy(conn); 2943 2944 conn->smp = NULL; 2945 l2cap_chan_put(chan); 2946 } 2947 2948 static void bredr_pairing(struct l2cap_chan *chan) 2949 { 2950 struct l2cap_conn *conn = chan->conn; 2951 struct hci_conn *hcon = conn->hcon; 2952 struct hci_dev *hdev = hcon->hdev; 2953 struct smp_cmd_pairing req; 2954 struct smp_chan *smp; 2955 2956 BT_DBG("chan %p", chan); 2957 2958 /* Only new pairings are interesting */ 2959 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 2960 return; 2961 2962 /* Don't bother if we're not encrypted */ 2963 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 2964 return; 2965 2966 /* Only master may initiate SMP over BR/EDR */ 2967 if (hcon->role != HCI_ROLE_MASTER) 2968 return; 2969 2970 /* Secure Connections support must be enabled */ 2971 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 2972 return; 2973 2974 /* BR/EDR must use Secure Connections for SMP */ 2975 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 2976 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 2977 return; 2978 2979 /* If our LE support is not enabled don't do anything */ 2980 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 2981 return; 2982 2983 /* Don't bother if remote LE support is not enabled */ 2984 if (!lmp_host_le_capable(hcon)) 2985 return; 2986 2987 /* Remote must support SMP fixed chan for BR/EDR */ 2988 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 2989 return; 2990 2991 /* Don't bother if SMP is already ongoing */ 2992 if (chan->data) 2993 return; 2994 2995 smp = smp_chan_create(conn); 2996 if (!smp) { 2997 BT_ERR("%s unable to create SMP context for BR/EDR", 2998 hdev->name); 2999 return; 3000 } 3001 3002 set_bit(SMP_FLAG_SC, &smp->flags); 3003 3004 BT_DBG("%s starting SMP over BR/EDR", hdev->name); 3005 3006 /* Prepare and send the BR/EDR SMP Pairing Request */ 3007 build_bredr_pairing_cmd(smp, &req, NULL); 3008 3009 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3010 memcpy(&smp->preq[1], &req, sizeof(req)); 3011 3012 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3013 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3014 } 3015 3016 static void smp_resume_cb(struct l2cap_chan *chan) 3017 { 3018 struct smp_chan *smp = chan->data; 3019 struct l2cap_conn *conn = chan->conn; 3020 struct hci_conn *hcon = conn->hcon; 3021 3022 BT_DBG("chan %p", chan); 3023 3024 if (hcon->type == ACL_LINK) { 3025 bredr_pairing(chan); 3026 return; 3027 } 3028 3029 if (!smp) 3030 return; 3031 3032 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3033 return; 3034 3035 cancel_delayed_work(&smp->security_timer); 3036 3037 smp_distribute_keys(smp); 3038 } 3039 3040 static void smp_ready_cb(struct l2cap_chan *chan) 3041 { 3042 struct l2cap_conn *conn = chan->conn; 3043 struct hci_conn *hcon = conn->hcon; 3044 3045 BT_DBG("chan %p", chan); 3046 3047 /* No need to call l2cap_chan_hold() here since we already own 3048 * the reference taken in smp_new_conn_cb(). This is just the 3049 * first time that we tie it to a specific pointer. The code in 3050 * l2cap_core.c ensures that there's no risk this function wont 3051 * get called if smp_new_conn_cb was previously called. 3052 */ 3053 conn->smp = chan; 3054 3055 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3056 bredr_pairing(chan); 3057 } 3058 3059 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3060 { 3061 int err; 3062 3063 BT_DBG("chan %p", chan); 3064 3065 err = smp_sig_channel(chan, skb); 3066 if (err) { 3067 struct smp_chan *smp = chan->data; 3068 3069 if (smp) 3070 cancel_delayed_work_sync(&smp->security_timer); 3071 3072 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3073 } 3074 3075 return err; 3076 } 3077 3078 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3079 unsigned long hdr_len, 3080 unsigned long len, int nb) 3081 { 3082 struct sk_buff *skb; 3083 3084 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3085 if (!skb) 3086 return ERR_PTR(-ENOMEM); 3087 3088 skb->priority = HCI_PRIO_MAX; 3089 bt_cb(skb)->l2cap.chan = chan; 3090 3091 return skb; 3092 } 3093 3094 static const struct l2cap_ops smp_chan_ops = { 3095 .name = "Security Manager", 3096 .ready = smp_ready_cb, 3097 .recv = smp_recv_cb, 3098 .alloc_skb = smp_alloc_skb_cb, 3099 .teardown = smp_teardown_cb, 3100 .resume = smp_resume_cb, 3101 3102 .new_connection = l2cap_chan_no_new_connection, 3103 .state_change = l2cap_chan_no_state_change, 3104 .close = l2cap_chan_no_close, 3105 .defer = l2cap_chan_no_defer, 3106 .suspend = l2cap_chan_no_suspend, 3107 .set_shutdown = l2cap_chan_no_set_shutdown, 3108 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3109 }; 3110 3111 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3112 { 3113 struct l2cap_chan *chan; 3114 3115 BT_DBG("pchan %p", pchan); 3116 3117 chan = l2cap_chan_create(); 3118 if (!chan) 3119 return NULL; 3120 3121 chan->chan_type = pchan->chan_type; 3122 chan->ops = &smp_chan_ops; 3123 chan->scid = pchan->scid; 3124 chan->dcid = chan->scid; 3125 chan->imtu = pchan->imtu; 3126 chan->omtu = pchan->omtu; 3127 chan->mode = pchan->mode; 3128 3129 /* Other L2CAP channels may request SMP routines in order to 3130 * change the security level. This means that the SMP channel 3131 * lock must be considered in its own category to avoid lockdep 3132 * warnings. 3133 */ 3134 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3135 3136 BT_DBG("created chan %p", chan); 3137 3138 return chan; 3139 } 3140 3141 static const struct l2cap_ops smp_root_chan_ops = { 3142 .name = "Security Manager Root", 3143 .new_connection = smp_new_conn_cb, 3144 3145 /* None of these are implemented for the root channel */ 3146 .close = l2cap_chan_no_close, 3147 .alloc_skb = l2cap_chan_no_alloc_skb, 3148 .recv = l2cap_chan_no_recv, 3149 .state_change = l2cap_chan_no_state_change, 3150 .teardown = l2cap_chan_no_teardown, 3151 .ready = l2cap_chan_no_ready, 3152 .defer = l2cap_chan_no_defer, 3153 .suspend = l2cap_chan_no_suspend, 3154 .resume = l2cap_chan_no_resume, 3155 .set_shutdown = l2cap_chan_no_set_shutdown, 3156 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3157 }; 3158 3159 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3160 { 3161 struct l2cap_chan *chan; 3162 struct smp_dev *smp; 3163 struct crypto_cipher *tfm_aes; 3164 struct crypto_shash *tfm_cmac; 3165 3166 if (cid == L2CAP_CID_SMP_BREDR) { 3167 smp = NULL; 3168 goto create_chan; 3169 } 3170 3171 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3172 if (!smp) 3173 return ERR_PTR(-ENOMEM); 3174 3175 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 3176 if (IS_ERR(tfm_aes)) { 3177 BT_ERR("Unable to create AES crypto context"); 3178 kzfree(smp); 3179 return ERR_CAST(tfm_aes); 3180 } 3181 3182 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3183 if (IS_ERR(tfm_cmac)) { 3184 BT_ERR("Unable to create CMAC crypto context"); 3185 crypto_free_cipher(tfm_aes); 3186 kzfree(smp); 3187 return ERR_CAST(tfm_cmac); 3188 } 3189 3190 smp->tfm_aes = tfm_aes; 3191 smp->tfm_cmac = tfm_cmac; 3192 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE; 3193 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE; 3194 3195 create_chan: 3196 chan = l2cap_chan_create(); 3197 if (!chan) { 3198 if (smp) { 3199 crypto_free_cipher(smp->tfm_aes); 3200 crypto_free_shash(smp->tfm_cmac); 3201 kzfree(smp); 3202 } 3203 return ERR_PTR(-ENOMEM); 3204 } 3205 3206 chan->data = smp; 3207 3208 l2cap_add_scid(chan, cid); 3209 3210 l2cap_chan_set_defaults(chan); 3211 3212 if (cid == L2CAP_CID_SMP) { 3213 u8 bdaddr_type; 3214 3215 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3216 3217 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3218 chan->src_type = BDADDR_LE_PUBLIC; 3219 else 3220 chan->src_type = BDADDR_LE_RANDOM; 3221 } else { 3222 bacpy(&chan->src, &hdev->bdaddr); 3223 chan->src_type = BDADDR_BREDR; 3224 } 3225 3226 chan->state = BT_LISTEN; 3227 chan->mode = L2CAP_MODE_BASIC; 3228 chan->imtu = L2CAP_DEFAULT_MTU; 3229 chan->ops = &smp_root_chan_ops; 3230 3231 /* Set correct nesting level for a parent/listening channel */ 3232 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3233 3234 return chan; 3235 } 3236 3237 static void smp_del_chan(struct l2cap_chan *chan) 3238 { 3239 struct smp_dev *smp; 3240 3241 BT_DBG("chan %p", chan); 3242 3243 smp = chan->data; 3244 if (smp) { 3245 chan->data = NULL; 3246 crypto_free_cipher(smp->tfm_aes); 3247 crypto_free_shash(smp->tfm_cmac); 3248 kzfree(smp); 3249 } 3250 3251 l2cap_chan_put(chan); 3252 } 3253 3254 static ssize_t force_bredr_smp_read(struct file *file, 3255 char __user *user_buf, 3256 size_t count, loff_t *ppos) 3257 { 3258 struct hci_dev *hdev = file->private_data; 3259 char buf[3]; 3260 3261 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N'; 3262 buf[1] = '\n'; 3263 buf[2] = '\0'; 3264 return simple_read_from_buffer(user_buf, count, ppos, buf, 2); 3265 } 3266 3267 static ssize_t force_bredr_smp_write(struct file *file, 3268 const char __user *user_buf, 3269 size_t count, loff_t *ppos) 3270 { 3271 struct hci_dev *hdev = file->private_data; 3272 char buf[32]; 3273 size_t buf_size = min(count, (sizeof(buf)-1)); 3274 bool enable; 3275 3276 if (copy_from_user(buf, user_buf, buf_size)) 3277 return -EFAULT; 3278 3279 buf[buf_size] = '\0'; 3280 if (strtobool(buf, &enable)) 3281 return -EINVAL; 3282 3283 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3284 return -EALREADY; 3285 3286 if (enable) { 3287 struct l2cap_chan *chan; 3288 3289 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3290 if (IS_ERR(chan)) 3291 return PTR_ERR(chan); 3292 3293 hdev->smp_bredr_data = chan; 3294 } else { 3295 struct l2cap_chan *chan; 3296 3297 chan = hdev->smp_bredr_data; 3298 hdev->smp_bredr_data = NULL; 3299 smp_del_chan(chan); 3300 } 3301 3302 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3303 3304 return count; 3305 } 3306 3307 static const struct file_operations force_bredr_smp_fops = { 3308 .open = simple_open, 3309 .read = force_bredr_smp_read, 3310 .write = force_bredr_smp_write, 3311 .llseek = default_llseek, 3312 }; 3313 3314 static ssize_t le_min_key_size_read(struct file *file, 3315 char __user *user_buf, 3316 size_t count, loff_t *ppos) 3317 { 3318 struct hci_dev *hdev = file->private_data; 3319 char buf[4]; 3320 3321 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size); 3322 3323 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); 3324 } 3325 3326 static ssize_t le_min_key_size_write(struct file *file, 3327 const char __user *user_buf, 3328 size_t count, loff_t *ppos) 3329 { 3330 struct hci_dev *hdev = file->private_data; 3331 char buf[32]; 3332 size_t buf_size = min(count, (sizeof(buf) - 1)); 3333 u8 key_size; 3334 3335 if (copy_from_user(buf, user_buf, buf_size)) 3336 return -EFAULT; 3337 3338 buf[buf_size] = '\0'; 3339 3340 sscanf(buf, "%hhu", &key_size); 3341 3342 if (key_size > SMP_DEV(hdev)->max_key_size || 3343 key_size < SMP_MIN_ENC_KEY_SIZE) 3344 return -EINVAL; 3345 3346 SMP_DEV(hdev)->min_key_size = key_size; 3347 3348 return count; 3349 } 3350 3351 static const struct file_operations le_min_key_size_fops = { 3352 .open = simple_open, 3353 .read = le_min_key_size_read, 3354 .write = le_min_key_size_write, 3355 .llseek = default_llseek, 3356 }; 3357 3358 static ssize_t le_max_key_size_read(struct file *file, 3359 char __user *user_buf, 3360 size_t count, loff_t *ppos) 3361 { 3362 struct hci_dev *hdev = file->private_data; 3363 char buf[4]; 3364 3365 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size); 3366 3367 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); 3368 } 3369 3370 static ssize_t le_max_key_size_write(struct file *file, 3371 const char __user *user_buf, 3372 size_t count, loff_t *ppos) 3373 { 3374 struct hci_dev *hdev = file->private_data; 3375 char buf[32]; 3376 size_t buf_size = min(count, (sizeof(buf) - 1)); 3377 u8 key_size; 3378 3379 if (copy_from_user(buf, user_buf, buf_size)) 3380 return -EFAULT; 3381 3382 buf[buf_size] = '\0'; 3383 3384 sscanf(buf, "%hhu", &key_size); 3385 3386 if (key_size > SMP_MAX_ENC_KEY_SIZE || 3387 key_size < SMP_DEV(hdev)->min_key_size) 3388 return -EINVAL; 3389 3390 SMP_DEV(hdev)->max_key_size = key_size; 3391 3392 return count; 3393 } 3394 3395 static const struct file_operations le_max_key_size_fops = { 3396 .open = simple_open, 3397 .read = le_max_key_size_read, 3398 .write = le_max_key_size_write, 3399 .llseek = default_llseek, 3400 }; 3401 3402 int smp_register(struct hci_dev *hdev) 3403 { 3404 struct l2cap_chan *chan; 3405 3406 BT_DBG("%s", hdev->name); 3407 3408 /* If the controller does not support Low Energy operation, then 3409 * there is also no need to register any SMP channel. 3410 */ 3411 if (!lmp_le_capable(hdev)) 3412 return 0; 3413 3414 if (WARN_ON(hdev->smp_data)) { 3415 chan = hdev->smp_data; 3416 hdev->smp_data = NULL; 3417 smp_del_chan(chan); 3418 } 3419 3420 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3421 if (IS_ERR(chan)) 3422 return PTR_ERR(chan); 3423 3424 hdev->smp_data = chan; 3425 3426 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev, 3427 &le_min_key_size_fops); 3428 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev, 3429 &le_max_key_size_fops); 3430 3431 /* If the controller does not support BR/EDR Secure Connections 3432 * feature, then the BR/EDR SMP channel shall not be present. 3433 * 3434 * To test this with Bluetooth 4.0 controllers, create a debugfs 3435 * switch that allows forcing BR/EDR SMP support and accepting 3436 * cross-transport pairing on non-AES encrypted connections. 3437 */ 3438 if (!lmp_sc_capable(hdev)) { 3439 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs, 3440 hdev, &force_bredr_smp_fops); 3441 3442 /* Flag can be already set here (due to power toggle) */ 3443 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3444 return 0; 3445 } 3446 3447 if (WARN_ON(hdev->smp_bredr_data)) { 3448 chan = hdev->smp_bredr_data; 3449 hdev->smp_bredr_data = NULL; 3450 smp_del_chan(chan); 3451 } 3452 3453 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3454 if (IS_ERR(chan)) { 3455 int err = PTR_ERR(chan); 3456 chan = hdev->smp_data; 3457 hdev->smp_data = NULL; 3458 smp_del_chan(chan); 3459 return err; 3460 } 3461 3462 hdev->smp_bredr_data = chan; 3463 3464 return 0; 3465 } 3466 3467 void smp_unregister(struct hci_dev *hdev) 3468 { 3469 struct l2cap_chan *chan; 3470 3471 if (hdev->smp_bredr_data) { 3472 chan = hdev->smp_bredr_data; 3473 hdev->smp_bredr_data = NULL; 3474 smp_del_chan(chan); 3475 } 3476 3477 if (hdev->smp_data) { 3478 chan = hdev->smp_data; 3479 hdev->smp_data = NULL; 3480 smp_del_chan(chan); 3481 } 3482 } 3483 3484 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3485 3486 static int __init test_ah(struct crypto_cipher *tfm_aes) 3487 { 3488 const u8 irk[16] = { 3489 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3490 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3491 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3492 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3493 u8 res[3]; 3494 int err; 3495 3496 err = smp_ah(tfm_aes, irk, r, res); 3497 if (err) 3498 return err; 3499 3500 if (memcmp(res, exp, 3)) 3501 return -EINVAL; 3502 3503 return 0; 3504 } 3505 3506 static int __init test_c1(struct crypto_cipher *tfm_aes) 3507 { 3508 const u8 k[16] = { 3509 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3510 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3511 const u8 r[16] = { 3512 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3513 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3514 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3515 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3516 const u8 _iat = 0x01; 3517 const u8 _rat = 0x00; 3518 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3519 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3520 const u8 exp[16] = { 3521 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3522 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3523 u8 res[16]; 3524 int err; 3525 3526 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3527 if (err) 3528 return err; 3529 3530 if (memcmp(res, exp, 16)) 3531 return -EINVAL; 3532 3533 return 0; 3534 } 3535 3536 static int __init test_s1(struct crypto_cipher *tfm_aes) 3537 { 3538 const u8 k[16] = { 3539 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3540 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3541 const u8 r1[16] = { 3542 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3543 const u8 r2[16] = { 3544 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3545 const u8 exp[16] = { 3546 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3547 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3548 u8 res[16]; 3549 int err; 3550 3551 err = smp_s1(tfm_aes, k, r1, r2, res); 3552 if (err) 3553 return err; 3554 3555 if (memcmp(res, exp, 16)) 3556 return -EINVAL; 3557 3558 return 0; 3559 } 3560 3561 static int __init test_f4(struct crypto_shash *tfm_cmac) 3562 { 3563 const u8 u[32] = { 3564 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3565 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3566 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3567 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3568 const u8 v[32] = { 3569 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3570 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3571 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3572 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3573 const u8 x[16] = { 3574 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3575 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3576 const u8 z = 0x00; 3577 const u8 exp[16] = { 3578 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3579 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3580 u8 res[16]; 3581 int err; 3582 3583 err = smp_f4(tfm_cmac, u, v, x, z, res); 3584 if (err) 3585 return err; 3586 3587 if (memcmp(res, exp, 16)) 3588 return -EINVAL; 3589 3590 return 0; 3591 } 3592 3593 static int __init test_f5(struct crypto_shash *tfm_cmac) 3594 { 3595 const u8 w[32] = { 3596 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3597 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3598 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3599 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3600 const u8 n1[16] = { 3601 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3602 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3603 const u8 n2[16] = { 3604 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3605 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3606 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3607 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3608 const u8 exp_ltk[16] = { 3609 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3610 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3611 const u8 exp_mackey[16] = { 3612 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3613 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3614 u8 mackey[16], ltk[16]; 3615 int err; 3616 3617 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3618 if (err) 3619 return err; 3620 3621 if (memcmp(mackey, exp_mackey, 16)) 3622 return -EINVAL; 3623 3624 if (memcmp(ltk, exp_ltk, 16)) 3625 return -EINVAL; 3626 3627 return 0; 3628 } 3629 3630 static int __init test_f6(struct crypto_shash *tfm_cmac) 3631 { 3632 const u8 w[16] = { 3633 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3634 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3635 const u8 n1[16] = { 3636 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3637 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3638 const u8 n2[16] = { 3639 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3640 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3641 const u8 r[16] = { 3642 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3643 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3644 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3645 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3646 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3647 const u8 exp[16] = { 3648 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3649 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3650 u8 res[16]; 3651 int err; 3652 3653 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3654 if (err) 3655 return err; 3656 3657 if (memcmp(res, exp, 16)) 3658 return -EINVAL; 3659 3660 return 0; 3661 } 3662 3663 static int __init test_g2(struct crypto_shash *tfm_cmac) 3664 { 3665 const u8 u[32] = { 3666 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3667 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3668 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3669 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3670 const u8 v[32] = { 3671 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3672 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3673 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3674 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3675 const u8 x[16] = { 3676 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3677 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3678 const u8 y[16] = { 3679 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3680 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3681 const u32 exp_val = 0x2f9ed5ba % 1000000; 3682 u32 val; 3683 int err; 3684 3685 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3686 if (err) 3687 return err; 3688 3689 if (val != exp_val) 3690 return -EINVAL; 3691 3692 return 0; 3693 } 3694 3695 static int __init test_h6(struct crypto_shash *tfm_cmac) 3696 { 3697 const u8 w[16] = { 3698 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3699 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3700 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3701 const u8 exp[16] = { 3702 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3703 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3704 u8 res[16]; 3705 int err; 3706 3707 err = smp_h6(tfm_cmac, w, key_id, res); 3708 if (err) 3709 return err; 3710 3711 if (memcmp(res, exp, 16)) 3712 return -EINVAL; 3713 3714 return 0; 3715 } 3716 3717 static char test_smp_buffer[32]; 3718 3719 static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3720 size_t count, loff_t *ppos) 3721 { 3722 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3723 strlen(test_smp_buffer)); 3724 } 3725 3726 static const struct file_operations test_smp_fops = { 3727 .open = simple_open, 3728 .read = test_smp_read, 3729 .llseek = default_llseek, 3730 }; 3731 3732 static int __init run_selftests(struct crypto_cipher *tfm_aes, 3733 struct crypto_shash *tfm_cmac) 3734 { 3735 ktime_t calltime, delta, rettime; 3736 unsigned long long duration; 3737 int err; 3738 3739 calltime = ktime_get(); 3740 3741 err = test_ah(tfm_aes); 3742 if (err) { 3743 BT_ERR("smp_ah test failed"); 3744 goto done; 3745 } 3746 3747 err = test_c1(tfm_aes); 3748 if (err) { 3749 BT_ERR("smp_c1 test failed"); 3750 goto done; 3751 } 3752 3753 err = test_s1(tfm_aes); 3754 if (err) { 3755 BT_ERR("smp_s1 test failed"); 3756 goto done; 3757 } 3758 3759 err = test_f4(tfm_cmac); 3760 if (err) { 3761 BT_ERR("smp_f4 test failed"); 3762 goto done; 3763 } 3764 3765 err = test_f5(tfm_cmac); 3766 if (err) { 3767 BT_ERR("smp_f5 test failed"); 3768 goto done; 3769 } 3770 3771 err = test_f6(tfm_cmac); 3772 if (err) { 3773 BT_ERR("smp_f6 test failed"); 3774 goto done; 3775 } 3776 3777 err = test_g2(tfm_cmac); 3778 if (err) { 3779 BT_ERR("smp_g2 test failed"); 3780 goto done; 3781 } 3782 3783 err = test_h6(tfm_cmac); 3784 if (err) { 3785 BT_ERR("smp_h6 test failed"); 3786 goto done; 3787 } 3788 3789 rettime = ktime_get(); 3790 delta = ktime_sub(rettime, calltime); 3791 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3792 3793 BT_INFO("SMP test passed in %llu usecs", duration); 3794 3795 done: 3796 if (!err) 3797 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3798 "PASS (%llu usecs)\n", duration); 3799 else 3800 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3801 3802 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3803 &test_smp_fops); 3804 3805 return err; 3806 } 3807 3808 int __init bt_selftest_smp(void) 3809 { 3810 struct crypto_cipher *tfm_aes; 3811 struct crypto_shash *tfm_cmac; 3812 int err; 3813 3814 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 3815 if (IS_ERR(tfm_aes)) { 3816 BT_ERR("Unable to create AES crypto context"); 3817 return PTR_ERR(tfm_aes); 3818 } 3819 3820 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC); 3821 if (IS_ERR(tfm_cmac)) { 3822 BT_ERR("Unable to create CMAC crypto context"); 3823 crypto_free_cipher(tfm_aes); 3824 return PTR_ERR(tfm_cmac); 3825 } 3826 3827 err = run_selftests(tfm_aes, tfm_cmac); 3828 3829 crypto_free_shash(tfm_cmac); 3830 crypto_free_cipher(tfm_aes); 3831 3832 return err; 3833 } 3834 3835 #endif 3836