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/algapi.h> 27 #include <crypto/b128ops.h> 28 #include <crypto/hash.h> 29 #include <crypto/kpp.h> 30 31 #include <net/bluetooth/bluetooth.h> 32 #include <net/bluetooth/hci_core.h> 33 #include <net/bluetooth/l2cap.h> 34 #include <net/bluetooth/mgmt.h> 35 36 #include "ecdh_helper.h" 37 #include "smp.h" 38 39 #define SMP_DEV(hdev) \ 40 ((struct smp_dev *)((struct l2cap_chan *)((hdev)->smp_data))->data) 41 42 /* Low-level debug macros to be used for stuff that we don't want 43 * accidentially in dmesg, i.e. the values of the various crypto keys 44 * and the inputs & outputs of crypto functions. 45 */ 46 #ifdef DEBUG 47 #define SMP_DBG(fmt, ...) printk(KERN_DEBUG "%s: " fmt, __func__, \ 48 ##__VA_ARGS__) 49 #else 50 #define SMP_DBG(fmt, ...) no_printk(KERN_DEBUG "%s: " fmt, __func__, \ 51 ##__VA_ARGS__) 52 #endif 53 54 #define SMP_ALLOW_CMD(smp, code) set_bit(code, &smp->allow_cmd) 55 56 /* Keys which are not distributed with Secure Connections */ 57 #define SMP_SC_NO_DIST (SMP_DIST_ENC_KEY | SMP_DIST_LINK_KEY); 58 59 #define SMP_TIMEOUT msecs_to_jiffies(30000) 60 61 #define AUTH_REQ_MASK(dev) (hci_dev_test_flag(dev, HCI_SC_ENABLED) ? \ 62 0x3f : 0x07) 63 #define KEY_DIST_MASK 0x07 64 65 /* Maximum message length that can be passed to aes_cmac */ 66 #define CMAC_MSG_MAX 80 67 68 enum { 69 SMP_FLAG_TK_VALID, 70 SMP_FLAG_CFM_PENDING, 71 SMP_FLAG_MITM_AUTH, 72 SMP_FLAG_COMPLETE, 73 SMP_FLAG_INITIATOR, 74 SMP_FLAG_SC, 75 SMP_FLAG_REMOTE_PK, 76 SMP_FLAG_DEBUG_KEY, 77 SMP_FLAG_WAIT_USER, 78 SMP_FLAG_DHKEY_PENDING, 79 SMP_FLAG_REMOTE_OOB, 80 SMP_FLAG_LOCAL_OOB, 81 SMP_FLAG_CT2, 82 }; 83 84 struct smp_dev { 85 /* Secure Connections OOB data */ 86 u8 local_pk[64]; 87 u8 local_rand[16]; 88 bool debug_key; 89 90 u8 min_key_size; 91 u8 max_key_size; 92 93 struct crypto_cipher *tfm_aes; 94 struct crypto_shash *tfm_cmac; 95 struct crypto_kpp *tfm_ecdh; 96 }; 97 98 struct smp_chan { 99 struct l2cap_conn *conn; 100 struct delayed_work security_timer; 101 unsigned long allow_cmd; /* Bitmask of allowed commands */ 102 103 u8 preq[7]; /* SMP Pairing Request */ 104 u8 prsp[7]; /* SMP Pairing Response */ 105 u8 prnd[16]; /* SMP Pairing Random (local) */ 106 u8 rrnd[16]; /* SMP Pairing Random (remote) */ 107 u8 pcnf[16]; /* SMP Pairing Confirm */ 108 u8 tk[16]; /* SMP Temporary Key */ 109 u8 rr[16]; /* Remote OOB ra/rb value */ 110 u8 lr[16]; /* Local OOB ra/rb value */ 111 u8 enc_key_size; 112 u8 remote_key_dist; 113 bdaddr_t id_addr; 114 u8 id_addr_type; 115 u8 irk[16]; 116 struct smp_csrk *csrk; 117 struct smp_csrk *slave_csrk; 118 struct smp_ltk *ltk; 119 struct smp_ltk *slave_ltk; 120 struct smp_irk *remote_irk; 121 u8 *link_key; 122 unsigned long flags; 123 u8 method; 124 u8 passkey_round; 125 126 /* Secure Connections variables */ 127 u8 local_pk[64]; 128 u8 remote_pk[64]; 129 u8 dhkey[32]; 130 u8 mackey[16]; 131 132 struct crypto_cipher *tfm_aes; 133 struct crypto_shash *tfm_cmac; 134 struct crypto_kpp *tfm_ecdh; 135 }; 136 137 /* These debug key values are defined in the SMP section of the core 138 * specification. debug_pk is the public debug key and debug_sk the 139 * private debug key. 140 */ 141 static const u8 debug_pk[64] = { 142 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 143 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 144 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 145 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 146 147 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 148 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 149 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 150 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 151 }; 152 153 static const u8 debug_sk[32] = { 154 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 155 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 156 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 157 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 158 }; 159 160 static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 161 { 162 size_t i; 163 164 for (i = 0; i < len; i++) 165 dst[len - 1 - i] = src[i]; 166 } 167 168 /* The following functions map to the LE SC SMP crypto functions 169 * AES-CMAC, f4, f5, f6, g2 and h6. 170 */ 171 172 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 173 size_t len, u8 mac[16]) 174 { 175 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 176 SHASH_DESC_ON_STACK(desc, tfm); 177 int err; 178 179 if (len > CMAC_MSG_MAX) 180 return -EFBIG; 181 182 if (!tfm) { 183 BT_ERR("tfm %p", tfm); 184 return -EINVAL; 185 } 186 187 desc->tfm = tfm; 188 desc->flags = 0; 189 190 /* Swap key and message from LSB to MSB */ 191 swap_buf(k, tmp, 16); 192 swap_buf(m, msg_msb, len); 193 194 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 195 SMP_DBG("key %16phN", k); 196 197 err = crypto_shash_setkey(tfm, tmp, 16); 198 if (err) { 199 BT_ERR("cipher setkey failed: %d", err); 200 return err; 201 } 202 203 err = crypto_shash_digest(desc, msg_msb, len, mac_msb); 204 shash_desc_zero(desc); 205 if (err) { 206 BT_ERR("Hash computation error %d", err); 207 return err; 208 } 209 210 swap_buf(mac_msb, mac, 16); 211 212 SMP_DBG("mac %16phN", mac); 213 214 return 0; 215 } 216 217 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 218 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 219 { 220 u8 m[65]; 221 int err; 222 223 SMP_DBG("u %32phN", u); 224 SMP_DBG("v %32phN", v); 225 SMP_DBG("x %16phN z %02x", x, z); 226 227 m[0] = z; 228 memcpy(m + 1, v, 32); 229 memcpy(m + 33, u, 32); 230 231 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 232 if (err) 233 return err; 234 235 SMP_DBG("res %16phN", res); 236 237 return err; 238 } 239 240 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 241 const u8 n1[16], const u8 n2[16], const u8 a1[7], 242 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 243 { 244 /* The btle, salt and length "magic" values are as defined in 245 * the SMP section of the Bluetooth core specification. In ASCII 246 * the btle value ends up being 'btle'. The salt is just a 247 * random number whereas length is the value 256 in little 248 * endian format. 249 */ 250 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 251 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 252 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 253 const u8 length[2] = { 0x00, 0x01 }; 254 u8 m[53], t[16]; 255 int err; 256 257 SMP_DBG("w %32phN", w); 258 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 259 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 260 261 err = aes_cmac(tfm_cmac, salt, w, 32, t); 262 if (err) 263 return err; 264 265 SMP_DBG("t %16phN", t); 266 267 memcpy(m, length, 2); 268 memcpy(m + 2, a2, 7); 269 memcpy(m + 9, a1, 7); 270 memcpy(m + 16, n2, 16); 271 memcpy(m + 32, n1, 16); 272 memcpy(m + 48, btle, 4); 273 274 m[52] = 0; /* Counter */ 275 276 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 277 if (err) 278 return err; 279 280 SMP_DBG("mackey %16phN", mackey); 281 282 m[52] = 1; /* Counter */ 283 284 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 285 if (err) 286 return err; 287 288 SMP_DBG("ltk %16phN", ltk); 289 290 return 0; 291 } 292 293 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 294 const u8 n1[16], const u8 n2[16], const u8 r[16], 295 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 296 u8 res[16]) 297 { 298 u8 m[65]; 299 int err; 300 301 SMP_DBG("w %16phN", w); 302 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 303 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 304 305 memcpy(m, a2, 7); 306 memcpy(m + 7, a1, 7); 307 memcpy(m + 14, io_cap, 3); 308 memcpy(m + 17, r, 16); 309 memcpy(m + 33, n2, 16); 310 memcpy(m + 49, n1, 16); 311 312 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 313 if (err) 314 return err; 315 316 SMP_DBG("res %16phN", res); 317 318 return err; 319 } 320 321 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 322 const u8 x[16], const u8 y[16], u32 *val) 323 { 324 u8 m[80], tmp[16]; 325 int err; 326 327 SMP_DBG("u %32phN", u); 328 SMP_DBG("v %32phN", v); 329 SMP_DBG("x %16phN y %16phN", x, y); 330 331 memcpy(m, y, 16); 332 memcpy(m + 16, v, 32); 333 memcpy(m + 48, u, 32); 334 335 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 336 if (err) 337 return err; 338 339 *val = get_unaligned_le32(tmp); 340 *val %= 1000000; 341 342 SMP_DBG("val %06u", *val); 343 344 return 0; 345 } 346 347 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 348 const u8 key_id[4], u8 res[16]) 349 { 350 int err; 351 352 SMP_DBG("w %16phN key_id %4phN", w, key_id); 353 354 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 355 if (err) 356 return err; 357 358 SMP_DBG("res %16phN", res); 359 360 return err; 361 } 362 363 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 364 const u8 salt[16], u8 res[16]) 365 { 366 int err; 367 368 SMP_DBG("w %16phN salt %16phN", w, salt); 369 370 err = aes_cmac(tfm_cmac, salt, w, 16, res); 371 if (err) 372 return err; 373 374 SMP_DBG("res %16phN", res); 375 376 return err; 377 } 378 379 /* The following functions map to the legacy SMP crypto functions e, c1, 380 * s1 and ah. 381 */ 382 383 static int smp_e(struct crypto_cipher *tfm, const u8 *k, u8 *r) 384 { 385 uint8_t tmp[16], data[16]; 386 int err; 387 388 SMP_DBG("k %16phN r %16phN", k, r); 389 390 if (!tfm) { 391 BT_ERR("tfm %p", tfm); 392 return -EINVAL; 393 } 394 395 /* The most significant octet of key corresponds to k[0] */ 396 swap_buf(k, tmp, 16); 397 398 err = crypto_cipher_setkey(tfm, tmp, 16); 399 if (err) { 400 BT_ERR("cipher setkey failed: %d", err); 401 return err; 402 } 403 404 /* Most significant octet of plaintextData corresponds to data[0] */ 405 swap_buf(r, data, 16); 406 407 crypto_cipher_encrypt_one(tfm, data, data); 408 409 /* Most significant octet of encryptedData corresponds to data[0] */ 410 swap_buf(data, r, 16); 411 412 SMP_DBG("r %16phN", r); 413 414 return err; 415 } 416 417 static int smp_c1(struct crypto_cipher *tfm_aes, const u8 k[16], 418 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 419 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 420 { 421 u8 p1[16], p2[16]; 422 int err; 423 424 SMP_DBG("k %16phN r %16phN", k, r); 425 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 426 SMP_DBG("preq %7phN pres %7phN", preq, pres); 427 428 memset(p1, 0, 16); 429 430 /* p1 = pres || preq || _rat || _iat */ 431 p1[0] = _iat; 432 p1[1] = _rat; 433 memcpy(p1 + 2, preq, 7); 434 memcpy(p1 + 9, pres, 7); 435 436 SMP_DBG("p1 %16phN", p1); 437 438 /* res = r XOR p1 */ 439 u128_xor((u128 *) res, (u128 *) r, (u128 *) p1); 440 441 /* res = e(k, res) */ 442 err = smp_e(tfm_aes, k, res); 443 if (err) { 444 BT_ERR("Encrypt data error"); 445 return err; 446 } 447 448 /* p2 = padding || ia || ra */ 449 memcpy(p2, ra, 6); 450 memcpy(p2 + 6, ia, 6); 451 memset(p2 + 12, 0, 4); 452 453 SMP_DBG("p2 %16phN", p2); 454 455 /* res = res XOR p2 */ 456 u128_xor((u128 *) res, (u128 *) res, (u128 *) p2); 457 458 /* res = e(k, res) */ 459 err = smp_e(tfm_aes, k, res); 460 if (err) 461 BT_ERR("Encrypt data error"); 462 463 return err; 464 } 465 466 static int smp_s1(struct crypto_cipher *tfm_aes, const u8 k[16], 467 const u8 r1[16], const u8 r2[16], u8 _r[16]) 468 { 469 int err; 470 471 /* Just least significant octets from r1 and r2 are considered */ 472 memcpy(_r, r2, 8); 473 memcpy(_r + 8, r1, 8); 474 475 err = smp_e(tfm_aes, k, _r); 476 if (err) 477 BT_ERR("Encrypt data error"); 478 479 return err; 480 } 481 482 static int smp_ah(struct crypto_cipher *tfm, const u8 irk[16], 483 const u8 r[3], u8 res[3]) 484 { 485 u8 _res[16]; 486 int err; 487 488 /* r' = padding || r */ 489 memcpy(_res, r, 3); 490 memset(_res + 3, 0, 13); 491 492 err = smp_e(tfm, irk, _res); 493 if (err) { 494 BT_ERR("Encrypt error"); 495 return err; 496 } 497 498 /* The output of the random address function ah is: 499 * ah(k, r) = e(k, r') mod 2^24 500 * The output of the security function e is then truncated to 24 bits 501 * by taking the least significant 24 bits of the output of e as the 502 * result of ah. 503 */ 504 memcpy(res, _res, 3); 505 506 return 0; 507 } 508 509 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 510 const bdaddr_t *bdaddr) 511 { 512 struct l2cap_chan *chan = hdev->smp_data; 513 struct smp_dev *smp; 514 u8 hash[3]; 515 int err; 516 517 if (!chan || !chan->data) 518 return false; 519 520 smp = chan->data; 521 522 BT_DBG("RPA %pMR IRK %*phN", bdaddr, 16, irk); 523 524 err = smp_ah(smp->tfm_aes, irk, &bdaddr->b[3], hash); 525 if (err) 526 return false; 527 528 return !crypto_memneq(bdaddr->b, hash, 3); 529 } 530 531 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 532 { 533 struct l2cap_chan *chan = hdev->smp_data; 534 struct smp_dev *smp; 535 int err; 536 537 if (!chan || !chan->data) 538 return -EOPNOTSUPP; 539 540 smp = chan->data; 541 542 get_random_bytes(&rpa->b[3], 3); 543 544 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 545 rpa->b[5] |= 0x40; /* Set second most significant bit */ 546 547 err = smp_ah(smp->tfm_aes, irk, &rpa->b[3], rpa->b); 548 if (err < 0) 549 return err; 550 551 BT_DBG("RPA %pMR", rpa); 552 553 return 0; 554 } 555 556 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 557 { 558 struct l2cap_chan *chan = hdev->smp_data; 559 struct smp_dev *smp; 560 int err; 561 562 if (!chan || !chan->data) 563 return -EOPNOTSUPP; 564 565 smp = chan->data; 566 567 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 568 BT_DBG("Using debug keys"); 569 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk); 570 if (err) 571 return err; 572 memcpy(smp->local_pk, debug_pk, 64); 573 smp->debug_key = true; 574 } else { 575 while (true) { 576 /* Generate key pair for Secure Connections */ 577 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk); 578 if (err) 579 return err; 580 581 /* This is unlikely, but we need to check that 582 * we didn't accidentially generate a debug key. 583 */ 584 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 585 break; 586 } 587 smp->debug_key = false; 588 } 589 590 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 591 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 592 593 get_random_bytes(smp->local_rand, 16); 594 595 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 596 smp->local_rand, 0, hash); 597 if (err < 0) 598 return err; 599 600 memcpy(rand, smp->local_rand, 16); 601 602 return 0; 603 } 604 605 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 606 { 607 struct l2cap_chan *chan = conn->smp; 608 struct smp_chan *smp; 609 struct kvec iv[2]; 610 struct msghdr msg; 611 612 if (!chan) 613 return; 614 615 BT_DBG("code 0x%2.2x", code); 616 617 iv[0].iov_base = &code; 618 iv[0].iov_len = 1; 619 620 iv[1].iov_base = data; 621 iv[1].iov_len = len; 622 623 memset(&msg, 0, sizeof(msg)); 624 625 iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, iv, 2, 1 + len); 626 627 l2cap_chan_send(chan, &msg, 1 + len); 628 629 if (!chan->data) 630 return; 631 632 smp = chan->data; 633 634 cancel_delayed_work_sync(&smp->security_timer); 635 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 636 } 637 638 static u8 authreq_to_seclevel(u8 authreq) 639 { 640 if (authreq & SMP_AUTH_MITM) { 641 if (authreq & SMP_AUTH_SC) 642 return BT_SECURITY_FIPS; 643 else 644 return BT_SECURITY_HIGH; 645 } else { 646 return BT_SECURITY_MEDIUM; 647 } 648 } 649 650 static __u8 seclevel_to_authreq(__u8 sec_level) 651 { 652 switch (sec_level) { 653 case BT_SECURITY_FIPS: 654 case BT_SECURITY_HIGH: 655 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 656 case BT_SECURITY_MEDIUM: 657 return SMP_AUTH_BONDING; 658 default: 659 return SMP_AUTH_NONE; 660 } 661 } 662 663 static void build_pairing_cmd(struct l2cap_conn *conn, 664 struct smp_cmd_pairing *req, 665 struct smp_cmd_pairing *rsp, __u8 authreq) 666 { 667 struct l2cap_chan *chan = conn->smp; 668 struct smp_chan *smp = chan->data; 669 struct hci_conn *hcon = conn->hcon; 670 struct hci_dev *hdev = hcon->hdev; 671 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 672 673 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 674 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 675 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 676 authreq |= SMP_AUTH_BONDING; 677 } else { 678 authreq &= ~SMP_AUTH_BONDING; 679 } 680 681 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 682 remote_dist |= SMP_DIST_ID_KEY; 683 684 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 685 local_dist |= SMP_DIST_ID_KEY; 686 687 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 688 (authreq & SMP_AUTH_SC)) { 689 struct oob_data *oob_data; 690 u8 bdaddr_type; 691 692 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 693 local_dist |= SMP_DIST_LINK_KEY; 694 remote_dist |= SMP_DIST_LINK_KEY; 695 } 696 697 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 698 bdaddr_type = BDADDR_LE_PUBLIC; 699 else 700 bdaddr_type = BDADDR_LE_RANDOM; 701 702 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 703 bdaddr_type); 704 if (oob_data && oob_data->present) { 705 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 706 oob_flag = SMP_OOB_PRESENT; 707 memcpy(smp->rr, oob_data->rand256, 16); 708 memcpy(smp->pcnf, oob_data->hash256, 16); 709 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 710 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 711 } 712 713 } else { 714 authreq &= ~SMP_AUTH_SC; 715 } 716 717 if (rsp == NULL) { 718 req->io_capability = conn->hcon->io_capability; 719 req->oob_flag = oob_flag; 720 req->max_key_size = SMP_DEV(hdev)->max_key_size; 721 req->init_key_dist = local_dist; 722 req->resp_key_dist = remote_dist; 723 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 724 725 smp->remote_key_dist = remote_dist; 726 return; 727 } 728 729 rsp->io_capability = conn->hcon->io_capability; 730 rsp->oob_flag = oob_flag; 731 rsp->max_key_size = SMP_DEV(hdev)->max_key_size; 732 rsp->init_key_dist = req->init_key_dist & remote_dist; 733 rsp->resp_key_dist = req->resp_key_dist & local_dist; 734 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 735 736 smp->remote_key_dist = rsp->init_key_dist; 737 } 738 739 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 740 { 741 struct l2cap_chan *chan = conn->smp; 742 struct hci_dev *hdev = conn->hcon->hdev; 743 struct smp_chan *smp = chan->data; 744 745 if (max_key_size > SMP_DEV(hdev)->max_key_size || 746 max_key_size < SMP_MIN_ENC_KEY_SIZE) 747 return SMP_ENC_KEY_SIZE; 748 749 smp->enc_key_size = max_key_size; 750 751 return 0; 752 } 753 754 static void smp_chan_destroy(struct l2cap_conn *conn) 755 { 756 struct l2cap_chan *chan = conn->smp; 757 struct smp_chan *smp = chan->data; 758 struct hci_conn *hcon = conn->hcon; 759 bool complete; 760 761 BUG_ON(!smp); 762 763 cancel_delayed_work_sync(&smp->security_timer); 764 765 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 766 mgmt_smp_complete(hcon, complete); 767 768 kzfree(smp->csrk); 769 kzfree(smp->slave_csrk); 770 kzfree(smp->link_key); 771 772 crypto_free_cipher(smp->tfm_aes); 773 crypto_free_shash(smp->tfm_cmac); 774 crypto_free_kpp(smp->tfm_ecdh); 775 776 /* Ensure that we don't leave any debug key around if debug key 777 * support hasn't been explicitly enabled. 778 */ 779 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 780 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 781 list_del_rcu(&smp->ltk->list); 782 kfree_rcu(smp->ltk, rcu); 783 smp->ltk = NULL; 784 } 785 786 /* If pairing failed clean up any keys we might have */ 787 if (!complete) { 788 if (smp->ltk) { 789 list_del_rcu(&smp->ltk->list); 790 kfree_rcu(smp->ltk, rcu); 791 } 792 793 if (smp->slave_ltk) { 794 list_del_rcu(&smp->slave_ltk->list); 795 kfree_rcu(smp->slave_ltk, rcu); 796 } 797 798 if (smp->remote_irk) { 799 list_del_rcu(&smp->remote_irk->list); 800 kfree_rcu(smp->remote_irk, rcu); 801 } 802 } 803 804 chan->data = NULL; 805 kzfree(smp); 806 hci_conn_drop(hcon); 807 } 808 809 static void smp_failure(struct l2cap_conn *conn, u8 reason) 810 { 811 struct hci_conn *hcon = conn->hcon; 812 struct l2cap_chan *chan = conn->smp; 813 814 if (reason) 815 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 816 &reason); 817 818 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 819 820 if (chan->data) 821 smp_chan_destroy(conn); 822 } 823 824 #define JUST_WORKS 0x00 825 #define JUST_CFM 0x01 826 #define REQ_PASSKEY 0x02 827 #define CFM_PASSKEY 0x03 828 #define REQ_OOB 0x04 829 #define DSP_PASSKEY 0x05 830 #define OVERLAP 0xFF 831 832 static const u8 gen_method[5][5] = { 833 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 834 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 835 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 836 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 837 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 838 }; 839 840 static const u8 sc_method[5][5] = { 841 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 842 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 843 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 844 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 845 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 846 }; 847 848 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 849 { 850 /* If either side has unknown io_caps, use JUST_CFM (which gets 851 * converted later to JUST_WORKS if we're initiators. 852 */ 853 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 854 remote_io > SMP_IO_KEYBOARD_DISPLAY) 855 return JUST_CFM; 856 857 if (test_bit(SMP_FLAG_SC, &smp->flags)) 858 return sc_method[remote_io][local_io]; 859 860 return gen_method[remote_io][local_io]; 861 } 862 863 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 864 u8 local_io, u8 remote_io) 865 { 866 struct hci_conn *hcon = conn->hcon; 867 struct l2cap_chan *chan = conn->smp; 868 struct smp_chan *smp = chan->data; 869 u32 passkey = 0; 870 int ret = 0; 871 872 /* Initialize key for JUST WORKS */ 873 memset(smp->tk, 0, sizeof(smp->tk)); 874 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 875 876 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); 877 878 /* If neither side wants MITM, either "just" confirm an incoming 879 * request or use just-works for outgoing ones. The JUST_CFM 880 * will be converted to JUST_WORKS if necessary later in this 881 * function. If either side has MITM look up the method from the 882 * table. 883 */ 884 if (!(auth & SMP_AUTH_MITM)) 885 smp->method = JUST_CFM; 886 else 887 smp->method = get_auth_method(smp, local_io, remote_io); 888 889 /* Don't confirm locally initiated pairing attempts */ 890 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 891 &smp->flags)) 892 smp->method = JUST_WORKS; 893 894 /* Don't bother user space with no IO capabilities */ 895 if (smp->method == JUST_CFM && 896 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 897 smp->method = JUST_WORKS; 898 899 /* If Just Works, Continue with Zero TK */ 900 if (smp->method == JUST_WORKS) { 901 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 902 return 0; 903 } 904 905 /* If this function is used for SC -> legacy fallback we 906 * can only recover the just-works case. 907 */ 908 if (test_bit(SMP_FLAG_SC, &smp->flags)) 909 return -EINVAL; 910 911 /* Not Just Works/Confirm results in MITM Authentication */ 912 if (smp->method != JUST_CFM) { 913 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); 914 if (hcon->pending_sec_level < BT_SECURITY_HIGH) 915 hcon->pending_sec_level = BT_SECURITY_HIGH; 916 } 917 918 /* If both devices have Keyoard-Display I/O, the master 919 * Confirms and the slave Enters the passkey. 920 */ 921 if (smp->method == OVERLAP) { 922 if (hcon->role == HCI_ROLE_MASTER) 923 smp->method = CFM_PASSKEY; 924 else 925 smp->method = REQ_PASSKEY; 926 } 927 928 /* Generate random passkey. */ 929 if (smp->method == CFM_PASSKEY) { 930 memset(smp->tk, 0, sizeof(smp->tk)); 931 get_random_bytes(&passkey, sizeof(passkey)); 932 passkey %= 1000000; 933 put_unaligned_le32(passkey, smp->tk); 934 BT_DBG("PassKey: %d", passkey); 935 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 936 } 937 938 if (smp->method == REQ_PASSKEY) 939 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, 940 hcon->type, hcon->dst_type); 941 else if (smp->method == JUST_CFM) 942 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 943 hcon->type, hcon->dst_type, 944 passkey, 1); 945 else 946 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, 947 hcon->type, hcon->dst_type, 948 passkey, 0); 949 950 return ret; 951 } 952 953 static u8 smp_confirm(struct smp_chan *smp) 954 { 955 struct l2cap_conn *conn = smp->conn; 956 struct smp_cmd_pairing_confirm cp; 957 int ret; 958 959 BT_DBG("conn %p", conn); 960 961 ret = smp_c1(smp->tfm_aes, smp->tk, smp->prnd, smp->preq, smp->prsp, 962 conn->hcon->init_addr_type, &conn->hcon->init_addr, 963 conn->hcon->resp_addr_type, &conn->hcon->resp_addr, 964 cp.confirm_val); 965 if (ret) 966 return SMP_UNSPECIFIED; 967 968 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 969 970 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); 971 972 if (conn->hcon->out) 973 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 974 else 975 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 976 977 return 0; 978 } 979 980 static u8 smp_random(struct smp_chan *smp) 981 { 982 struct l2cap_conn *conn = smp->conn; 983 struct hci_conn *hcon = conn->hcon; 984 u8 confirm[16]; 985 int ret; 986 987 if (IS_ERR_OR_NULL(smp->tfm_aes)) 988 return SMP_UNSPECIFIED; 989 990 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 991 992 ret = smp_c1(smp->tfm_aes, smp->tk, smp->rrnd, smp->preq, smp->prsp, 993 hcon->init_addr_type, &hcon->init_addr, 994 hcon->resp_addr_type, &hcon->resp_addr, confirm); 995 if (ret) 996 return SMP_UNSPECIFIED; 997 998 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) { 999 bt_dev_err(hcon->hdev, "pairing failed " 1000 "(confirmation values mismatch)"); 1001 return SMP_CONFIRM_FAILED; 1002 } 1003 1004 if (hcon->out) { 1005 u8 stk[16]; 1006 __le64 rand = 0; 1007 __le16 ediv = 0; 1008 1009 smp_s1(smp->tfm_aes, smp->tk, smp->rrnd, smp->prnd, stk); 1010 1011 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 1012 return SMP_UNSPECIFIED; 1013 1014 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 1015 hcon->enc_key_size = smp->enc_key_size; 1016 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1017 } else { 1018 u8 stk[16], auth; 1019 __le64 rand = 0; 1020 __le16 ediv = 0; 1021 1022 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1023 smp->prnd); 1024 1025 smp_s1(smp->tfm_aes, smp->tk, smp->prnd, smp->rrnd, stk); 1026 1027 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1028 auth = 1; 1029 else 1030 auth = 0; 1031 1032 /* Even though there's no _SLAVE suffix this is the 1033 * slave STK we're adding for later lookup (the master 1034 * STK never needs to be stored). 1035 */ 1036 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1037 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1038 } 1039 1040 return 0; 1041 } 1042 1043 static void smp_notify_keys(struct l2cap_conn *conn) 1044 { 1045 struct l2cap_chan *chan = conn->smp; 1046 struct smp_chan *smp = chan->data; 1047 struct hci_conn *hcon = conn->hcon; 1048 struct hci_dev *hdev = hcon->hdev; 1049 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1050 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1051 bool persistent; 1052 1053 if (hcon->type == ACL_LINK) { 1054 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1055 persistent = false; 1056 else 1057 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1058 &hcon->flags); 1059 } else { 1060 /* The LTKs, IRKs and CSRKs should be persistent only if 1061 * both sides had the bonding bit set in their 1062 * authentication requests. 1063 */ 1064 persistent = !!((req->auth_req & rsp->auth_req) & 1065 SMP_AUTH_BONDING); 1066 } 1067 1068 if (smp->remote_irk) { 1069 mgmt_new_irk(hdev, smp->remote_irk, persistent); 1070 1071 /* Now that user space can be considered to know the 1072 * identity address track the connection based on it 1073 * from now on (assuming this is an LE link). 1074 */ 1075 if (hcon->type == LE_LINK) { 1076 bacpy(&hcon->dst, &smp->remote_irk->bdaddr); 1077 hcon->dst_type = smp->remote_irk->addr_type; 1078 queue_work(hdev->workqueue, &conn->id_addr_update_work); 1079 } 1080 } 1081 1082 if (smp->csrk) { 1083 smp->csrk->bdaddr_type = hcon->dst_type; 1084 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1085 mgmt_new_csrk(hdev, smp->csrk, persistent); 1086 } 1087 1088 if (smp->slave_csrk) { 1089 smp->slave_csrk->bdaddr_type = hcon->dst_type; 1090 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); 1091 mgmt_new_csrk(hdev, smp->slave_csrk, persistent); 1092 } 1093 1094 if (smp->ltk) { 1095 smp->ltk->bdaddr_type = hcon->dst_type; 1096 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1097 mgmt_new_ltk(hdev, smp->ltk, persistent); 1098 } 1099 1100 if (smp->slave_ltk) { 1101 smp->slave_ltk->bdaddr_type = hcon->dst_type; 1102 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); 1103 mgmt_new_ltk(hdev, smp->slave_ltk, persistent); 1104 } 1105 1106 if (smp->link_key) { 1107 struct link_key *key; 1108 u8 type; 1109 1110 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1111 type = HCI_LK_DEBUG_COMBINATION; 1112 else if (hcon->sec_level == BT_SECURITY_FIPS) 1113 type = HCI_LK_AUTH_COMBINATION_P256; 1114 else 1115 type = HCI_LK_UNAUTH_COMBINATION_P256; 1116 1117 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1118 smp->link_key, type, 0, &persistent); 1119 if (key) { 1120 mgmt_new_link_key(hdev, key, persistent); 1121 1122 /* Don't keep debug keys around if the relevant 1123 * flag is not set. 1124 */ 1125 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1126 key->type == HCI_LK_DEBUG_COMBINATION) { 1127 list_del_rcu(&key->list); 1128 kfree_rcu(key, rcu); 1129 } 1130 } 1131 } 1132 } 1133 1134 static void sc_add_ltk(struct smp_chan *smp) 1135 { 1136 struct hci_conn *hcon = smp->conn->hcon; 1137 u8 key_type, auth; 1138 1139 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1140 key_type = SMP_LTK_P256_DEBUG; 1141 else 1142 key_type = SMP_LTK_P256; 1143 1144 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1145 auth = 1; 1146 else 1147 auth = 0; 1148 1149 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1150 key_type, auth, smp->tk, smp->enc_key_size, 1151 0, 0); 1152 } 1153 1154 static void sc_generate_link_key(struct smp_chan *smp) 1155 { 1156 /* From core spec. Spells out in ASCII as 'lebr'. */ 1157 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1158 1159 smp->link_key = kzalloc(16, GFP_KERNEL); 1160 if (!smp->link_key) 1161 return; 1162 1163 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1164 /* SALT = 0x00000000000000000000000000000000746D7031 */ 1165 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1166 1167 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1168 kzfree(smp->link_key); 1169 smp->link_key = NULL; 1170 return; 1171 } 1172 } else { 1173 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1174 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1175 1176 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1177 kzfree(smp->link_key); 1178 smp->link_key = NULL; 1179 return; 1180 } 1181 } 1182 1183 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1184 kzfree(smp->link_key); 1185 smp->link_key = NULL; 1186 return; 1187 } 1188 } 1189 1190 static void smp_allow_key_dist(struct smp_chan *smp) 1191 { 1192 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1193 * will be allowed in each PDU handler to ensure we receive 1194 * them in the correct order. 1195 */ 1196 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1197 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1198 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1199 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1200 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1201 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1202 } 1203 1204 static void sc_generate_ltk(struct smp_chan *smp) 1205 { 1206 /* From core spec. Spells out in ASCII as 'brle'. */ 1207 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1208 struct hci_conn *hcon = smp->conn->hcon; 1209 struct hci_dev *hdev = hcon->hdev; 1210 struct link_key *key; 1211 1212 key = hci_find_link_key(hdev, &hcon->dst); 1213 if (!key) { 1214 bt_dev_err(hdev, "no Link Key found to generate LTK"); 1215 return; 1216 } 1217 1218 if (key->type == HCI_LK_DEBUG_COMBINATION) 1219 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1220 1221 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1222 /* SALT = 0x00000000000000000000000000000000746D7032 */ 1223 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1224 1225 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1226 return; 1227 } else { 1228 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1229 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1230 1231 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1232 return; 1233 } 1234 1235 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1236 return; 1237 1238 sc_add_ltk(smp); 1239 } 1240 1241 static void smp_distribute_keys(struct smp_chan *smp) 1242 { 1243 struct smp_cmd_pairing *req, *rsp; 1244 struct l2cap_conn *conn = smp->conn; 1245 struct hci_conn *hcon = conn->hcon; 1246 struct hci_dev *hdev = hcon->hdev; 1247 __u8 *keydist; 1248 1249 BT_DBG("conn %p", conn); 1250 1251 rsp = (void *) &smp->prsp[1]; 1252 1253 /* The responder sends its keys first */ 1254 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1255 smp_allow_key_dist(smp); 1256 return; 1257 } 1258 1259 req = (void *) &smp->preq[1]; 1260 1261 if (hcon->out) { 1262 keydist = &rsp->init_key_dist; 1263 *keydist &= req->init_key_dist; 1264 } else { 1265 keydist = &rsp->resp_key_dist; 1266 *keydist &= req->resp_key_dist; 1267 } 1268 1269 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1270 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1271 sc_generate_link_key(smp); 1272 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1273 sc_generate_ltk(smp); 1274 1275 /* Clear the keys which are generated but not distributed */ 1276 *keydist &= ~SMP_SC_NO_DIST; 1277 } 1278 1279 BT_DBG("keydist 0x%x", *keydist); 1280 1281 if (*keydist & SMP_DIST_ENC_KEY) { 1282 struct smp_cmd_encrypt_info enc; 1283 struct smp_cmd_master_ident ident; 1284 struct smp_ltk *ltk; 1285 u8 authenticated; 1286 __le16 ediv; 1287 __le64 rand; 1288 1289 /* Make sure we generate only the significant amount of 1290 * bytes based on the encryption key size, and set the rest 1291 * of the value to zeroes. 1292 */ 1293 get_random_bytes(enc.ltk, smp->enc_key_size); 1294 memset(enc.ltk + smp->enc_key_size, 0, 1295 sizeof(enc.ltk) - smp->enc_key_size); 1296 1297 get_random_bytes(&ediv, sizeof(ediv)); 1298 get_random_bytes(&rand, sizeof(rand)); 1299 1300 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1301 1302 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1303 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1304 SMP_LTK_SLAVE, authenticated, enc.ltk, 1305 smp->enc_key_size, ediv, rand); 1306 smp->slave_ltk = ltk; 1307 1308 ident.ediv = ediv; 1309 ident.rand = rand; 1310 1311 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); 1312 1313 *keydist &= ~SMP_DIST_ENC_KEY; 1314 } 1315 1316 if (*keydist & SMP_DIST_ID_KEY) { 1317 struct smp_cmd_ident_addr_info addrinfo; 1318 struct smp_cmd_ident_info idinfo; 1319 1320 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1321 1322 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1323 1324 /* The hci_conn contains the local identity address 1325 * after the connection has been established. 1326 * 1327 * This is true even when the connection has been 1328 * established using a resolvable random address. 1329 */ 1330 bacpy(&addrinfo.bdaddr, &hcon->src); 1331 addrinfo.addr_type = hcon->src_type; 1332 1333 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1334 &addrinfo); 1335 1336 *keydist &= ~SMP_DIST_ID_KEY; 1337 } 1338 1339 if (*keydist & SMP_DIST_SIGN) { 1340 struct smp_cmd_sign_info sign; 1341 struct smp_csrk *csrk; 1342 1343 /* Generate a new random key */ 1344 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1345 1346 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1347 if (csrk) { 1348 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1349 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1350 else 1351 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1352 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1353 } 1354 smp->slave_csrk = csrk; 1355 1356 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1357 1358 *keydist &= ~SMP_DIST_SIGN; 1359 } 1360 1361 /* If there are still keys to be received wait for them */ 1362 if (smp->remote_key_dist & KEY_DIST_MASK) { 1363 smp_allow_key_dist(smp); 1364 return; 1365 } 1366 1367 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1368 smp_notify_keys(conn); 1369 1370 smp_chan_destroy(conn); 1371 } 1372 1373 static void smp_timeout(struct work_struct *work) 1374 { 1375 struct smp_chan *smp = container_of(work, struct smp_chan, 1376 security_timer.work); 1377 struct l2cap_conn *conn = smp->conn; 1378 1379 BT_DBG("conn %p", conn); 1380 1381 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1382 } 1383 1384 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1385 { 1386 struct l2cap_chan *chan = conn->smp; 1387 struct smp_chan *smp; 1388 1389 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1390 if (!smp) 1391 return NULL; 1392 1393 smp->tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 1394 if (IS_ERR(smp->tfm_aes)) { 1395 BT_ERR("Unable to create AES crypto context"); 1396 goto zfree_smp; 1397 } 1398 1399 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1400 if (IS_ERR(smp->tfm_cmac)) { 1401 BT_ERR("Unable to create CMAC crypto context"); 1402 goto free_cipher; 1403 } 1404 1405 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 1406 if (IS_ERR(smp->tfm_ecdh)) { 1407 BT_ERR("Unable to create ECDH crypto context"); 1408 goto free_shash; 1409 } 1410 1411 smp->conn = conn; 1412 chan->data = smp; 1413 1414 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1415 1416 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1417 1418 hci_conn_hold(conn->hcon); 1419 1420 return smp; 1421 1422 free_shash: 1423 crypto_free_shash(smp->tfm_cmac); 1424 free_cipher: 1425 crypto_free_cipher(smp->tfm_aes); 1426 zfree_smp: 1427 kzfree(smp); 1428 return NULL; 1429 } 1430 1431 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1432 { 1433 struct hci_conn *hcon = smp->conn->hcon; 1434 u8 *na, *nb, a[7], b[7]; 1435 1436 if (hcon->out) { 1437 na = smp->prnd; 1438 nb = smp->rrnd; 1439 } else { 1440 na = smp->rrnd; 1441 nb = smp->prnd; 1442 } 1443 1444 memcpy(a, &hcon->init_addr, 6); 1445 memcpy(b, &hcon->resp_addr, 6); 1446 a[6] = hcon->init_addr_type; 1447 b[6] = hcon->resp_addr_type; 1448 1449 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1450 } 1451 1452 static void sc_dhkey_check(struct smp_chan *smp) 1453 { 1454 struct hci_conn *hcon = smp->conn->hcon; 1455 struct smp_cmd_dhkey_check check; 1456 u8 a[7], b[7], *local_addr, *remote_addr; 1457 u8 io_cap[3], r[16]; 1458 1459 memcpy(a, &hcon->init_addr, 6); 1460 memcpy(b, &hcon->resp_addr, 6); 1461 a[6] = hcon->init_addr_type; 1462 b[6] = hcon->resp_addr_type; 1463 1464 if (hcon->out) { 1465 local_addr = a; 1466 remote_addr = b; 1467 memcpy(io_cap, &smp->preq[1], 3); 1468 } else { 1469 local_addr = b; 1470 remote_addr = a; 1471 memcpy(io_cap, &smp->prsp[1], 3); 1472 } 1473 1474 memset(r, 0, sizeof(r)); 1475 1476 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1477 put_unaligned_le32(hcon->passkey_notify, r); 1478 1479 if (smp->method == REQ_OOB) 1480 memcpy(r, smp->rr, 16); 1481 1482 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1483 local_addr, remote_addr, check.e); 1484 1485 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1486 } 1487 1488 static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1489 { 1490 struct l2cap_conn *conn = smp->conn; 1491 struct hci_conn *hcon = conn->hcon; 1492 struct smp_cmd_pairing_confirm cfm; 1493 u8 r; 1494 1495 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1496 r |= 0x80; 1497 1498 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1499 1500 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1501 cfm.confirm_val)) 1502 return SMP_UNSPECIFIED; 1503 1504 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1505 1506 return 0; 1507 } 1508 1509 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1510 { 1511 struct l2cap_conn *conn = smp->conn; 1512 struct hci_conn *hcon = conn->hcon; 1513 struct hci_dev *hdev = hcon->hdev; 1514 u8 cfm[16], r; 1515 1516 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1517 if (smp->passkey_round >= 20) 1518 return 0; 1519 1520 switch (smp_op) { 1521 case SMP_CMD_PAIRING_RANDOM: 1522 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1523 r |= 0x80; 1524 1525 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1526 smp->rrnd, r, cfm)) 1527 return SMP_UNSPECIFIED; 1528 1529 if (crypto_memneq(smp->pcnf, cfm, 16)) 1530 return SMP_CONFIRM_FAILED; 1531 1532 smp->passkey_round++; 1533 1534 if (smp->passkey_round == 20) { 1535 /* Generate MacKey and LTK */ 1536 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1537 return SMP_UNSPECIFIED; 1538 } 1539 1540 /* The round is only complete when the initiator 1541 * receives pairing random. 1542 */ 1543 if (!hcon->out) { 1544 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1545 sizeof(smp->prnd), smp->prnd); 1546 if (smp->passkey_round == 20) 1547 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1548 else 1549 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1550 return 0; 1551 } 1552 1553 /* Start the next round */ 1554 if (smp->passkey_round != 20) 1555 return sc_passkey_round(smp, 0); 1556 1557 /* Passkey rounds are complete - start DHKey Check */ 1558 sc_dhkey_check(smp); 1559 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1560 1561 break; 1562 1563 case SMP_CMD_PAIRING_CONFIRM: 1564 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1565 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1566 return 0; 1567 } 1568 1569 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1570 1571 if (hcon->out) { 1572 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1573 sizeof(smp->prnd), smp->prnd); 1574 return 0; 1575 } 1576 1577 return sc_passkey_send_confirm(smp); 1578 1579 case SMP_CMD_PUBLIC_KEY: 1580 default: 1581 /* Initiating device starts the round */ 1582 if (!hcon->out) 1583 return 0; 1584 1585 BT_DBG("%s Starting passkey round %u", hdev->name, 1586 smp->passkey_round + 1); 1587 1588 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1589 1590 return sc_passkey_send_confirm(smp); 1591 } 1592 1593 return 0; 1594 } 1595 1596 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1597 { 1598 struct l2cap_conn *conn = smp->conn; 1599 struct hci_conn *hcon = conn->hcon; 1600 u8 smp_op; 1601 1602 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1603 1604 switch (mgmt_op) { 1605 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1606 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1607 return 0; 1608 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1609 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1610 return 0; 1611 case MGMT_OP_USER_PASSKEY_REPLY: 1612 hcon->passkey_notify = le32_to_cpu(passkey); 1613 smp->passkey_round = 0; 1614 1615 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1616 smp_op = SMP_CMD_PAIRING_CONFIRM; 1617 else 1618 smp_op = 0; 1619 1620 if (sc_passkey_round(smp, smp_op)) 1621 return -EIO; 1622 1623 return 0; 1624 } 1625 1626 /* Initiator sends DHKey check first */ 1627 if (hcon->out) { 1628 sc_dhkey_check(smp); 1629 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1630 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1631 sc_dhkey_check(smp); 1632 sc_add_ltk(smp); 1633 } 1634 1635 return 0; 1636 } 1637 1638 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1639 { 1640 struct l2cap_conn *conn = hcon->l2cap_data; 1641 struct l2cap_chan *chan; 1642 struct smp_chan *smp; 1643 u32 value; 1644 int err; 1645 1646 BT_DBG(""); 1647 1648 if (!conn) 1649 return -ENOTCONN; 1650 1651 chan = conn->smp; 1652 if (!chan) 1653 return -ENOTCONN; 1654 1655 l2cap_chan_lock(chan); 1656 if (!chan->data) { 1657 err = -ENOTCONN; 1658 goto unlock; 1659 } 1660 1661 smp = chan->data; 1662 1663 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1664 err = sc_user_reply(smp, mgmt_op, passkey); 1665 goto unlock; 1666 } 1667 1668 switch (mgmt_op) { 1669 case MGMT_OP_USER_PASSKEY_REPLY: 1670 value = le32_to_cpu(passkey); 1671 memset(smp->tk, 0, sizeof(smp->tk)); 1672 BT_DBG("PassKey: %d", value); 1673 put_unaligned_le32(value, smp->tk); 1674 /* Fall Through */ 1675 case MGMT_OP_USER_CONFIRM_REPLY: 1676 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1677 break; 1678 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1679 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1680 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1681 err = 0; 1682 goto unlock; 1683 default: 1684 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1685 err = -EOPNOTSUPP; 1686 goto unlock; 1687 } 1688 1689 err = 0; 1690 1691 /* If it is our turn to send Pairing Confirm, do so now */ 1692 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1693 u8 rsp = smp_confirm(smp); 1694 if (rsp) 1695 smp_failure(conn, rsp); 1696 } 1697 1698 unlock: 1699 l2cap_chan_unlock(chan); 1700 return err; 1701 } 1702 1703 static void build_bredr_pairing_cmd(struct smp_chan *smp, 1704 struct smp_cmd_pairing *req, 1705 struct smp_cmd_pairing *rsp) 1706 { 1707 struct l2cap_conn *conn = smp->conn; 1708 struct hci_dev *hdev = conn->hcon->hdev; 1709 u8 local_dist = 0, remote_dist = 0; 1710 1711 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1712 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1713 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1714 } 1715 1716 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1717 remote_dist |= SMP_DIST_ID_KEY; 1718 1719 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1720 local_dist |= SMP_DIST_ID_KEY; 1721 1722 if (!rsp) { 1723 memset(req, 0, sizeof(*req)); 1724 1725 req->auth_req = SMP_AUTH_CT2; 1726 req->init_key_dist = local_dist; 1727 req->resp_key_dist = remote_dist; 1728 req->max_key_size = conn->hcon->enc_key_size; 1729 1730 smp->remote_key_dist = remote_dist; 1731 1732 return; 1733 } 1734 1735 memset(rsp, 0, sizeof(*rsp)); 1736 1737 rsp->auth_req = SMP_AUTH_CT2; 1738 rsp->max_key_size = conn->hcon->enc_key_size; 1739 rsp->init_key_dist = req->init_key_dist & remote_dist; 1740 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1741 1742 smp->remote_key_dist = rsp->init_key_dist; 1743 } 1744 1745 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1746 { 1747 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1748 struct l2cap_chan *chan = conn->smp; 1749 struct hci_dev *hdev = conn->hcon->hdev; 1750 struct smp_chan *smp; 1751 u8 key_size, auth, sec_level; 1752 int ret; 1753 1754 BT_DBG("conn %p", conn); 1755 1756 if (skb->len < sizeof(*req)) 1757 return SMP_INVALID_PARAMS; 1758 1759 if (conn->hcon->role != HCI_ROLE_SLAVE) 1760 return SMP_CMD_NOTSUPP; 1761 1762 if (!chan->data) 1763 smp = smp_chan_create(conn); 1764 else 1765 smp = chan->data; 1766 1767 if (!smp) 1768 return SMP_UNSPECIFIED; 1769 1770 /* We didn't start the pairing, so match remote */ 1771 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1772 1773 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1774 (auth & SMP_AUTH_BONDING)) 1775 return SMP_PAIRING_NOTSUPP; 1776 1777 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1778 return SMP_AUTH_REQUIREMENTS; 1779 1780 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1781 memcpy(&smp->preq[1], req, sizeof(*req)); 1782 skb_pull(skb, sizeof(*req)); 1783 1784 /* If the remote side's OOB flag is set it means it has 1785 * successfully received our local OOB data - therefore set the 1786 * flag to indicate that local OOB is in use. 1787 */ 1788 if (req->oob_flag == SMP_OOB_PRESENT) 1789 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1790 1791 /* SMP over BR/EDR requires special treatment */ 1792 if (conn->hcon->type == ACL_LINK) { 1793 /* We must have a BR/EDR SC link */ 1794 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1795 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1796 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1797 1798 set_bit(SMP_FLAG_SC, &smp->flags); 1799 1800 build_bredr_pairing_cmd(smp, req, &rsp); 1801 1802 if (req->auth_req & SMP_AUTH_CT2) 1803 set_bit(SMP_FLAG_CT2, &smp->flags); 1804 1805 key_size = min(req->max_key_size, rsp.max_key_size); 1806 if (check_enc_key_size(conn, key_size)) 1807 return SMP_ENC_KEY_SIZE; 1808 1809 /* Clear bits which are generated but not distributed */ 1810 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1811 1812 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1813 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1814 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1815 1816 smp_distribute_keys(smp); 1817 return 0; 1818 } 1819 1820 build_pairing_cmd(conn, req, &rsp, auth); 1821 1822 if (rsp.auth_req & SMP_AUTH_SC) { 1823 set_bit(SMP_FLAG_SC, &smp->flags); 1824 1825 if (rsp.auth_req & SMP_AUTH_CT2) 1826 set_bit(SMP_FLAG_CT2, &smp->flags); 1827 } 1828 1829 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1830 sec_level = BT_SECURITY_MEDIUM; 1831 else 1832 sec_level = authreq_to_seclevel(auth); 1833 1834 if (sec_level > conn->hcon->pending_sec_level) 1835 conn->hcon->pending_sec_level = sec_level; 1836 1837 /* If we need MITM check that it can be achieved */ 1838 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1839 u8 method; 1840 1841 method = get_auth_method(smp, conn->hcon->io_capability, 1842 req->io_capability); 1843 if (method == JUST_WORKS || method == JUST_CFM) 1844 return SMP_AUTH_REQUIREMENTS; 1845 } 1846 1847 key_size = min(req->max_key_size, rsp.max_key_size); 1848 if (check_enc_key_size(conn, key_size)) 1849 return SMP_ENC_KEY_SIZE; 1850 1851 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1852 1853 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1854 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1855 1856 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1857 1858 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1859 1860 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1861 * SC case, however some implementations incorrectly copy RFU auth 1862 * req bits from our security request, which may create a false 1863 * positive SC enablement. 1864 */ 1865 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1866 1867 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1868 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1869 /* Clear bits which are generated but not distributed */ 1870 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1871 /* Wait for Public Key from Initiating Device */ 1872 return 0; 1873 } 1874 1875 /* Request setup of TK */ 1876 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1877 if (ret) 1878 return SMP_UNSPECIFIED; 1879 1880 return 0; 1881 } 1882 1883 static u8 sc_send_public_key(struct smp_chan *smp) 1884 { 1885 struct hci_dev *hdev = smp->conn->hcon->hdev; 1886 1887 BT_DBG(""); 1888 1889 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1890 struct l2cap_chan *chan = hdev->smp_data; 1891 struct smp_dev *smp_dev; 1892 1893 if (!chan || !chan->data) 1894 return SMP_UNSPECIFIED; 1895 1896 smp_dev = chan->data; 1897 1898 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1899 memcpy(smp->lr, smp_dev->local_rand, 16); 1900 1901 if (smp_dev->debug_key) 1902 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1903 1904 goto done; 1905 } 1906 1907 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1908 BT_DBG("Using debug keys"); 1909 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk)) 1910 return SMP_UNSPECIFIED; 1911 memcpy(smp->local_pk, debug_pk, 64); 1912 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1913 } else { 1914 while (true) { 1915 /* Generate key pair for Secure Connections */ 1916 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk)) 1917 return SMP_UNSPECIFIED; 1918 1919 /* This is unlikely, but we need to check that 1920 * we didn't accidentially generate a debug key. 1921 */ 1922 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 1923 break; 1924 } 1925 } 1926 1927 done: 1928 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1929 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1930 1931 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1932 1933 return 0; 1934 } 1935 1936 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1937 { 1938 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1939 struct l2cap_chan *chan = conn->smp; 1940 struct smp_chan *smp = chan->data; 1941 struct hci_dev *hdev = conn->hcon->hdev; 1942 u8 key_size, auth; 1943 int ret; 1944 1945 BT_DBG("conn %p", conn); 1946 1947 if (skb->len < sizeof(*rsp)) 1948 return SMP_INVALID_PARAMS; 1949 1950 if (conn->hcon->role != HCI_ROLE_MASTER) 1951 return SMP_CMD_NOTSUPP; 1952 1953 skb_pull(skb, sizeof(*rsp)); 1954 1955 req = (void *) &smp->preq[1]; 1956 1957 key_size = min(req->max_key_size, rsp->max_key_size); 1958 if (check_enc_key_size(conn, key_size)) 1959 return SMP_ENC_KEY_SIZE; 1960 1961 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1962 1963 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1964 return SMP_AUTH_REQUIREMENTS; 1965 1966 /* If the remote side's OOB flag is set it means it has 1967 * successfully received our local OOB data - therefore set the 1968 * flag to indicate that local OOB is in use. 1969 */ 1970 if (rsp->oob_flag == SMP_OOB_PRESENT) 1971 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1972 1973 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1974 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1975 1976 /* Update remote key distribution in case the remote cleared 1977 * some bits that we had enabled in our request. 1978 */ 1979 smp->remote_key_dist &= rsp->resp_key_dist; 1980 1981 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1982 set_bit(SMP_FLAG_CT2, &smp->flags); 1983 1984 /* For BR/EDR this means we're done and can start phase 3 */ 1985 if (conn->hcon->type == ACL_LINK) { 1986 /* Clear bits which are generated but not distributed */ 1987 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1988 smp_distribute_keys(smp); 1989 return 0; 1990 } 1991 1992 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1993 set_bit(SMP_FLAG_SC, &smp->flags); 1994 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1995 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1996 1997 /* If we need MITM check that it can be achieved */ 1998 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1999 u8 method; 2000 2001 method = get_auth_method(smp, req->io_capability, 2002 rsp->io_capability); 2003 if (method == JUST_WORKS || method == JUST_CFM) 2004 return SMP_AUTH_REQUIREMENTS; 2005 } 2006 2007 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 2008 2009 /* Update remote key distribution in case the remote cleared 2010 * some bits that we had enabled in our request. 2011 */ 2012 smp->remote_key_dist &= rsp->resp_key_dist; 2013 2014 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2015 /* Clear bits which are generated but not distributed */ 2016 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 2017 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 2018 return sc_send_public_key(smp); 2019 } 2020 2021 auth |= req->auth_req; 2022 2023 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2024 if (ret) 2025 return SMP_UNSPECIFIED; 2026 2027 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2028 2029 /* Can't compose response until we have been confirmed */ 2030 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2031 return smp_confirm(smp); 2032 2033 return 0; 2034 } 2035 2036 static u8 sc_check_confirm(struct smp_chan *smp) 2037 { 2038 struct l2cap_conn *conn = smp->conn; 2039 2040 BT_DBG(""); 2041 2042 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2043 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2044 2045 if (conn->hcon->out) { 2046 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2047 smp->prnd); 2048 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2049 } 2050 2051 return 0; 2052 } 2053 2054 /* Work-around for some implementations that incorrectly copy RFU bits 2055 * from our security request and thereby create the impression that 2056 * we're doing SC when in fact the remote doesn't support it. 2057 */ 2058 static int fixup_sc_false_positive(struct smp_chan *smp) 2059 { 2060 struct l2cap_conn *conn = smp->conn; 2061 struct hci_conn *hcon = conn->hcon; 2062 struct hci_dev *hdev = hcon->hdev; 2063 struct smp_cmd_pairing *req, *rsp; 2064 u8 auth; 2065 2066 /* The issue is only observed when we're in slave role */ 2067 if (hcon->out) 2068 return SMP_UNSPECIFIED; 2069 2070 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2071 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode"); 2072 return SMP_UNSPECIFIED; 2073 } 2074 2075 bt_dev_err(hdev, "trying to fall back to legacy SMP"); 2076 2077 req = (void *) &smp->preq[1]; 2078 rsp = (void *) &smp->prsp[1]; 2079 2080 /* Rebuild key dist flags which may have been cleared for SC */ 2081 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2082 2083 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2084 2085 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2086 bt_dev_err(hdev, "failed to fall back to legacy SMP"); 2087 return SMP_UNSPECIFIED; 2088 } 2089 2090 clear_bit(SMP_FLAG_SC, &smp->flags); 2091 2092 return 0; 2093 } 2094 2095 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2096 { 2097 struct l2cap_chan *chan = conn->smp; 2098 struct smp_chan *smp = chan->data; 2099 2100 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 2101 2102 if (skb->len < sizeof(smp->pcnf)) 2103 return SMP_INVALID_PARAMS; 2104 2105 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2106 skb_pull(skb, sizeof(smp->pcnf)); 2107 2108 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2109 int ret; 2110 2111 /* Public Key exchange must happen before any other steps */ 2112 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2113 return sc_check_confirm(smp); 2114 2115 BT_ERR("Unexpected SMP Pairing Confirm"); 2116 2117 ret = fixup_sc_false_positive(smp); 2118 if (ret) 2119 return ret; 2120 } 2121 2122 if (conn->hcon->out) { 2123 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2124 smp->prnd); 2125 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2126 return 0; 2127 } 2128 2129 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2130 return smp_confirm(smp); 2131 2132 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2133 2134 return 0; 2135 } 2136 2137 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2138 { 2139 struct l2cap_chan *chan = conn->smp; 2140 struct smp_chan *smp = chan->data; 2141 struct hci_conn *hcon = conn->hcon; 2142 u8 *pkax, *pkbx, *na, *nb; 2143 u32 passkey; 2144 int err; 2145 2146 BT_DBG("conn %p", conn); 2147 2148 if (skb->len < sizeof(smp->rrnd)) 2149 return SMP_INVALID_PARAMS; 2150 2151 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2152 skb_pull(skb, sizeof(smp->rrnd)); 2153 2154 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2155 return smp_random(smp); 2156 2157 if (hcon->out) { 2158 pkax = smp->local_pk; 2159 pkbx = smp->remote_pk; 2160 na = smp->prnd; 2161 nb = smp->rrnd; 2162 } else { 2163 pkax = smp->remote_pk; 2164 pkbx = smp->local_pk; 2165 na = smp->rrnd; 2166 nb = smp->prnd; 2167 } 2168 2169 if (smp->method == REQ_OOB) { 2170 if (!hcon->out) 2171 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2172 sizeof(smp->prnd), smp->prnd); 2173 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2174 goto mackey_and_ltk; 2175 } 2176 2177 /* Passkey entry has special treatment */ 2178 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2179 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2180 2181 if (hcon->out) { 2182 u8 cfm[16]; 2183 2184 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2185 smp->rrnd, 0, cfm); 2186 if (err) 2187 return SMP_UNSPECIFIED; 2188 2189 if (crypto_memneq(smp->pcnf, cfm, 16)) 2190 return SMP_CONFIRM_FAILED; 2191 } else { 2192 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2193 smp->prnd); 2194 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2195 } 2196 2197 mackey_and_ltk: 2198 /* Generate MacKey and LTK */ 2199 err = sc_mackey_and_ltk(smp, smp->mackey, smp->tk); 2200 if (err) 2201 return SMP_UNSPECIFIED; 2202 2203 if (smp->method == JUST_WORKS || smp->method == REQ_OOB) { 2204 if (hcon->out) { 2205 sc_dhkey_check(smp); 2206 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2207 } 2208 return 0; 2209 } 2210 2211 err = smp_g2(smp->tfm_cmac, pkax, pkbx, na, nb, &passkey); 2212 if (err) 2213 return SMP_UNSPECIFIED; 2214 2215 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2216 hcon->dst_type, passkey, 0); 2217 if (err) 2218 return SMP_UNSPECIFIED; 2219 2220 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2221 2222 return 0; 2223 } 2224 2225 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2226 { 2227 struct smp_ltk *key; 2228 struct hci_conn *hcon = conn->hcon; 2229 2230 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2231 if (!key) 2232 return false; 2233 2234 if (smp_ltk_sec_level(key) < sec_level) 2235 return false; 2236 2237 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2238 return true; 2239 2240 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2241 hcon->enc_key_size = key->enc_size; 2242 2243 /* We never store STKs for master role, so clear this flag */ 2244 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2245 2246 return true; 2247 } 2248 2249 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2250 enum smp_key_pref key_pref) 2251 { 2252 if (sec_level == BT_SECURITY_LOW) 2253 return true; 2254 2255 /* If we're encrypted with an STK but the caller prefers using 2256 * LTK claim insufficient security. This way we allow the 2257 * connection to be re-encrypted with an LTK, even if the LTK 2258 * provides the same level of security. Only exception is if we 2259 * don't have an LTK (e.g. because of key distribution bits). 2260 */ 2261 if (key_pref == SMP_USE_LTK && 2262 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2263 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2264 return false; 2265 2266 if (hcon->sec_level >= sec_level) 2267 return true; 2268 2269 return false; 2270 } 2271 2272 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2273 { 2274 struct smp_cmd_security_req *rp = (void *) skb->data; 2275 struct smp_cmd_pairing cp; 2276 struct hci_conn *hcon = conn->hcon; 2277 struct hci_dev *hdev = hcon->hdev; 2278 struct smp_chan *smp; 2279 u8 sec_level, auth; 2280 2281 BT_DBG("conn %p", conn); 2282 2283 if (skb->len < sizeof(*rp)) 2284 return SMP_INVALID_PARAMS; 2285 2286 if (hcon->role != HCI_ROLE_MASTER) 2287 return SMP_CMD_NOTSUPP; 2288 2289 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2290 2291 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2292 return SMP_AUTH_REQUIREMENTS; 2293 2294 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2295 sec_level = BT_SECURITY_MEDIUM; 2296 else 2297 sec_level = authreq_to_seclevel(auth); 2298 2299 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2300 return 0; 2301 2302 if (sec_level > hcon->pending_sec_level) 2303 hcon->pending_sec_level = sec_level; 2304 2305 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2306 return 0; 2307 2308 smp = smp_chan_create(conn); 2309 if (!smp) 2310 return SMP_UNSPECIFIED; 2311 2312 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2313 (auth & SMP_AUTH_BONDING)) 2314 return SMP_PAIRING_NOTSUPP; 2315 2316 skb_pull(skb, sizeof(*rp)); 2317 2318 memset(&cp, 0, sizeof(cp)); 2319 build_pairing_cmd(conn, &cp, NULL, auth); 2320 2321 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2322 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2323 2324 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2325 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2326 2327 return 0; 2328 } 2329 2330 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2331 { 2332 struct l2cap_conn *conn = hcon->l2cap_data; 2333 struct l2cap_chan *chan; 2334 struct smp_chan *smp; 2335 __u8 authreq; 2336 int ret; 2337 2338 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); 2339 2340 /* This may be NULL if there's an unexpected disconnection */ 2341 if (!conn) 2342 return 1; 2343 2344 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2345 return 1; 2346 2347 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2348 return 1; 2349 2350 if (sec_level > hcon->pending_sec_level) 2351 hcon->pending_sec_level = sec_level; 2352 2353 if (hcon->role == HCI_ROLE_MASTER) 2354 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2355 return 0; 2356 2357 chan = conn->smp; 2358 if (!chan) { 2359 bt_dev_err(hcon->hdev, "security requested but not available"); 2360 return 1; 2361 } 2362 2363 l2cap_chan_lock(chan); 2364 2365 /* If SMP is already in progress ignore this request */ 2366 if (chan->data) { 2367 ret = 0; 2368 goto unlock; 2369 } 2370 2371 smp = smp_chan_create(conn); 2372 if (!smp) { 2373 ret = 1; 2374 goto unlock; 2375 } 2376 2377 authreq = seclevel_to_authreq(sec_level); 2378 2379 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2380 authreq |= SMP_AUTH_SC; 2381 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2382 authreq |= SMP_AUTH_CT2; 2383 } 2384 2385 /* Require MITM if IO Capability allows or the security level 2386 * requires it. 2387 */ 2388 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2389 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2390 authreq |= SMP_AUTH_MITM; 2391 2392 if (hcon->role == HCI_ROLE_MASTER) { 2393 struct smp_cmd_pairing cp; 2394 2395 build_pairing_cmd(conn, &cp, NULL, authreq); 2396 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2397 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2398 2399 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2400 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2401 } else { 2402 struct smp_cmd_security_req cp; 2403 cp.auth_req = authreq; 2404 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2405 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2406 } 2407 2408 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2409 ret = 0; 2410 2411 unlock: 2412 l2cap_chan_unlock(chan); 2413 return ret; 2414 } 2415 2416 void smp_cancel_pairing(struct hci_conn *hcon) 2417 { 2418 struct l2cap_conn *conn = hcon->l2cap_data; 2419 struct l2cap_chan *chan; 2420 struct smp_chan *smp; 2421 2422 if (!conn) 2423 return; 2424 2425 chan = conn->smp; 2426 if (!chan) 2427 return; 2428 2429 l2cap_chan_lock(chan); 2430 2431 smp = chan->data; 2432 if (smp) { 2433 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2434 smp_failure(conn, 0); 2435 else 2436 smp_failure(conn, SMP_UNSPECIFIED); 2437 } 2438 2439 l2cap_chan_unlock(chan); 2440 } 2441 2442 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2443 { 2444 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2445 struct l2cap_chan *chan = conn->smp; 2446 struct smp_chan *smp = chan->data; 2447 2448 BT_DBG("conn %p", conn); 2449 2450 if (skb->len < sizeof(*rp)) 2451 return SMP_INVALID_PARAMS; 2452 2453 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); 2454 2455 skb_pull(skb, sizeof(*rp)); 2456 2457 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2458 2459 return 0; 2460 } 2461 2462 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2463 { 2464 struct smp_cmd_master_ident *rp = (void *) skb->data; 2465 struct l2cap_chan *chan = conn->smp; 2466 struct smp_chan *smp = chan->data; 2467 struct hci_dev *hdev = conn->hcon->hdev; 2468 struct hci_conn *hcon = conn->hcon; 2469 struct smp_ltk *ltk; 2470 u8 authenticated; 2471 2472 BT_DBG("conn %p", conn); 2473 2474 if (skb->len < sizeof(*rp)) 2475 return SMP_INVALID_PARAMS; 2476 2477 /* Mark the information as received */ 2478 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2479 2480 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2481 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2482 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2483 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2484 2485 skb_pull(skb, sizeof(*rp)); 2486 2487 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2488 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2489 authenticated, smp->tk, smp->enc_key_size, 2490 rp->ediv, rp->rand); 2491 smp->ltk = ltk; 2492 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2493 smp_distribute_keys(smp); 2494 2495 return 0; 2496 } 2497 2498 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2499 { 2500 struct smp_cmd_ident_info *info = (void *) skb->data; 2501 struct l2cap_chan *chan = conn->smp; 2502 struct smp_chan *smp = chan->data; 2503 2504 BT_DBG(""); 2505 2506 if (skb->len < sizeof(*info)) 2507 return SMP_INVALID_PARAMS; 2508 2509 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2510 2511 skb_pull(skb, sizeof(*info)); 2512 2513 memcpy(smp->irk, info->irk, 16); 2514 2515 return 0; 2516 } 2517 2518 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2519 struct sk_buff *skb) 2520 { 2521 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2522 struct l2cap_chan *chan = conn->smp; 2523 struct smp_chan *smp = chan->data; 2524 struct hci_conn *hcon = conn->hcon; 2525 bdaddr_t rpa; 2526 2527 BT_DBG(""); 2528 2529 if (skb->len < sizeof(*info)) 2530 return SMP_INVALID_PARAMS; 2531 2532 /* Mark the information as received */ 2533 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2534 2535 if (smp->remote_key_dist & SMP_DIST_SIGN) 2536 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2537 2538 skb_pull(skb, sizeof(*info)); 2539 2540 /* Strictly speaking the Core Specification (4.1) allows sending 2541 * an empty address which would force us to rely on just the IRK 2542 * as "identity information". However, since such 2543 * implementations are not known of and in order to not over 2544 * complicate our implementation, simply pretend that we never 2545 * received an IRK for such a device. 2546 * 2547 * The Identity Address must also be a Static Random or Public 2548 * Address, which hci_is_identity_address() checks for. 2549 */ 2550 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2551 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2552 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address"); 2553 goto distribute; 2554 } 2555 2556 bacpy(&smp->id_addr, &info->bdaddr); 2557 smp->id_addr_type = info->addr_type; 2558 2559 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2560 bacpy(&rpa, &hcon->dst); 2561 else 2562 bacpy(&rpa, BDADDR_ANY); 2563 2564 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2565 smp->id_addr_type, smp->irk, &rpa); 2566 2567 distribute: 2568 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2569 smp_distribute_keys(smp); 2570 2571 return 0; 2572 } 2573 2574 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2575 { 2576 struct smp_cmd_sign_info *rp = (void *) skb->data; 2577 struct l2cap_chan *chan = conn->smp; 2578 struct smp_chan *smp = chan->data; 2579 struct smp_csrk *csrk; 2580 2581 BT_DBG("conn %p", conn); 2582 2583 if (skb->len < sizeof(*rp)) 2584 return SMP_INVALID_PARAMS; 2585 2586 /* Mark the information as received */ 2587 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2588 2589 skb_pull(skb, sizeof(*rp)); 2590 2591 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2592 if (csrk) { 2593 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2594 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2595 else 2596 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2597 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2598 } 2599 smp->csrk = csrk; 2600 smp_distribute_keys(smp); 2601 2602 return 0; 2603 } 2604 2605 static u8 sc_select_method(struct smp_chan *smp) 2606 { 2607 struct l2cap_conn *conn = smp->conn; 2608 struct hci_conn *hcon = conn->hcon; 2609 struct smp_cmd_pairing *local, *remote; 2610 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2611 2612 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2613 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2614 return REQ_OOB; 2615 2616 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2617 * which are needed as inputs to some crypto functions. To get 2618 * the "struct smp_cmd_pairing" from them we need to skip the 2619 * first byte which contains the opcode. 2620 */ 2621 if (hcon->out) { 2622 local = (void *) &smp->preq[1]; 2623 remote = (void *) &smp->prsp[1]; 2624 } else { 2625 local = (void *) &smp->prsp[1]; 2626 remote = (void *) &smp->preq[1]; 2627 } 2628 2629 local_io = local->io_capability; 2630 remote_io = remote->io_capability; 2631 2632 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2633 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2634 2635 /* If either side wants MITM, look up the method from the table, 2636 * otherwise use JUST WORKS. 2637 */ 2638 if (local_mitm || remote_mitm) 2639 method = get_auth_method(smp, local_io, remote_io); 2640 else 2641 method = JUST_WORKS; 2642 2643 /* Don't confirm locally initiated pairing attempts */ 2644 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2645 method = JUST_WORKS; 2646 2647 return method; 2648 } 2649 2650 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2651 { 2652 struct smp_cmd_public_key *key = (void *) skb->data; 2653 struct hci_conn *hcon = conn->hcon; 2654 struct l2cap_chan *chan = conn->smp; 2655 struct smp_chan *smp = chan->data; 2656 struct hci_dev *hdev = hcon->hdev; 2657 struct crypto_kpp *tfm_ecdh; 2658 struct smp_cmd_pairing_confirm cfm; 2659 int err; 2660 2661 BT_DBG("conn %p", conn); 2662 2663 if (skb->len < sizeof(*key)) 2664 return SMP_INVALID_PARAMS; 2665 2666 memcpy(smp->remote_pk, key, 64); 2667 2668 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2669 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2670 smp->rr, 0, cfm.confirm_val); 2671 if (err) 2672 return SMP_UNSPECIFIED; 2673 2674 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16)) 2675 return SMP_CONFIRM_FAILED; 2676 } 2677 2678 /* Non-initiating device sends its public key after receiving 2679 * the key from the initiating device. 2680 */ 2681 if (!hcon->out) { 2682 err = sc_send_public_key(smp); 2683 if (err) 2684 return err; 2685 } 2686 2687 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2688 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2689 2690 /* Compute the shared secret on the same crypto tfm on which the private 2691 * key was set/generated. 2692 */ 2693 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 2694 struct smp_dev *smp_dev = chan->data; 2695 2696 tfm_ecdh = smp_dev->tfm_ecdh; 2697 } else { 2698 tfm_ecdh = smp->tfm_ecdh; 2699 } 2700 2701 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey)) 2702 return SMP_UNSPECIFIED; 2703 2704 SMP_DBG("DHKey %32phN", smp->dhkey); 2705 2706 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2707 2708 smp->method = sc_select_method(smp); 2709 2710 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method); 2711 2712 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2713 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2714 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2715 else 2716 hcon->pending_sec_level = BT_SECURITY_FIPS; 2717 2718 if (!crypto_memneq(debug_pk, smp->remote_pk, 64)) 2719 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2720 2721 if (smp->method == DSP_PASSKEY) { 2722 get_random_bytes(&hcon->passkey_notify, 2723 sizeof(hcon->passkey_notify)); 2724 hcon->passkey_notify %= 1000000; 2725 hcon->passkey_entered = 0; 2726 smp->passkey_round = 0; 2727 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2728 hcon->dst_type, 2729 hcon->passkey_notify, 2730 hcon->passkey_entered)) 2731 return SMP_UNSPECIFIED; 2732 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2733 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2734 } 2735 2736 if (smp->method == REQ_OOB) { 2737 if (hcon->out) 2738 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2739 sizeof(smp->prnd), smp->prnd); 2740 2741 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2742 2743 return 0; 2744 } 2745 2746 if (hcon->out) 2747 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2748 2749 if (smp->method == REQ_PASSKEY) { 2750 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2751 hcon->dst_type)) 2752 return SMP_UNSPECIFIED; 2753 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2754 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2755 return 0; 2756 } 2757 2758 /* The Initiating device waits for the non-initiating device to 2759 * send the confirm value. 2760 */ 2761 if (conn->hcon->out) 2762 return 0; 2763 2764 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2765 0, cfm.confirm_val); 2766 if (err) 2767 return SMP_UNSPECIFIED; 2768 2769 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2770 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2771 2772 return 0; 2773 } 2774 2775 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2776 { 2777 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2778 struct l2cap_chan *chan = conn->smp; 2779 struct hci_conn *hcon = conn->hcon; 2780 struct smp_chan *smp = chan->data; 2781 u8 a[7], b[7], *local_addr, *remote_addr; 2782 u8 io_cap[3], r[16], e[16]; 2783 int err; 2784 2785 BT_DBG("conn %p", conn); 2786 2787 if (skb->len < sizeof(*check)) 2788 return SMP_INVALID_PARAMS; 2789 2790 memcpy(a, &hcon->init_addr, 6); 2791 memcpy(b, &hcon->resp_addr, 6); 2792 a[6] = hcon->init_addr_type; 2793 b[6] = hcon->resp_addr_type; 2794 2795 if (hcon->out) { 2796 local_addr = a; 2797 remote_addr = b; 2798 memcpy(io_cap, &smp->prsp[1], 3); 2799 } else { 2800 local_addr = b; 2801 remote_addr = a; 2802 memcpy(io_cap, &smp->preq[1], 3); 2803 } 2804 2805 memset(r, 0, sizeof(r)); 2806 2807 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2808 put_unaligned_le32(hcon->passkey_notify, r); 2809 else if (smp->method == REQ_OOB) 2810 memcpy(r, smp->lr, 16); 2811 2812 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2813 io_cap, remote_addr, local_addr, e); 2814 if (err) 2815 return SMP_UNSPECIFIED; 2816 2817 if (crypto_memneq(check->e, e, 16)) 2818 return SMP_DHKEY_CHECK_FAILED; 2819 2820 if (!hcon->out) { 2821 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2822 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2823 return 0; 2824 } 2825 2826 /* Slave sends DHKey check as response to master */ 2827 sc_dhkey_check(smp); 2828 } 2829 2830 sc_add_ltk(smp); 2831 2832 if (hcon->out) { 2833 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2834 hcon->enc_key_size = smp->enc_key_size; 2835 } 2836 2837 return 0; 2838 } 2839 2840 static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2841 struct sk_buff *skb) 2842 { 2843 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2844 2845 BT_DBG("value 0x%02x", kp->value); 2846 2847 return 0; 2848 } 2849 2850 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2851 { 2852 struct l2cap_conn *conn = chan->conn; 2853 struct hci_conn *hcon = conn->hcon; 2854 struct smp_chan *smp; 2855 __u8 code, reason; 2856 int err = 0; 2857 2858 if (skb->len < 1) 2859 return -EILSEQ; 2860 2861 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2862 reason = SMP_PAIRING_NOTSUPP; 2863 goto done; 2864 } 2865 2866 code = skb->data[0]; 2867 skb_pull(skb, sizeof(code)); 2868 2869 smp = chan->data; 2870 2871 if (code > SMP_CMD_MAX) 2872 goto drop; 2873 2874 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2875 goto drop; 2876 2877 /* If we don't have a context the only allowed commands are 2878 * pairing request and security request. 2879 */ 2880 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2881 goto drop; 2882 2883 switch (code) { 2884 case SMP_CMD_PAIRING_REQ: 2885 reason = smp_cmd_pairing_req(conn, skb); 2886 break; 2887 2888 case SMP_CMD_PAIRING_FAIL: 2889 smp_failure(conn, 0); 2890 err = -EPERM; 2891 break; 2892 2893 case SMP_CMD_PAIRING_RSP: 2894 reason = smp_cmd_pairing_rsp(conn, skb); 2895 break; 2896 2897 case SMP_CMD_SECURITY_REQ: 2898 reason = smp_cmd_security_req(conn, skb); 2899 break; 2900 2901 case SMP_CMD_PAIRING_CONFIRM: 2902 reason = smp_cmd_pairing_confirm(conn, skb); 2903 break; 2904 2905 case SMP_CMD_PAIRING_RANDOM: 2906 reason = smp_cmd_pairing_random(conn, skb); 2907 break; 2908 2909 case SMP_CMD_ENCRYPT_INFO: 2910 reason = smp_cmd_encrypt_info(conn, skb); 2911 break; 2912 2913 case SMP_CMD_MASTER_IDENT: 2914 reason = smp_cmd_master_ident(conn, skb); 2915 break; 2916 2917 case SMP_CMD_IDENT_INFO: 2918 reason = smp_cmd_ident_info(conn, skb); 2919 break; 2920 2921 case SMP_CMD_IDENT_ADDR_INFO: 2922 reason = smp_cmd_ident_addr_info(conn, skb); 2923 break; 2924 2925 case SMP_CMD_SIGN_INFO: 2926 reason = smp_cmd_sign_info(conn, skb); 2927 break; 2928 2929 case SMP_CMD_PUBLIC_KEY: 2930 reason = smp_cmd_public_key(conn, skb); 2931 break; 2932 2933 case SMP_CMD_DHKEY_CHECK: 2934 reason = smp_cmd_dhkey_check(conn, skb); 2935 break; 2936 2937 case SMP_CMD_KEYPRESS_NOTIFY: 2938 reason = smp_cmd_keypress_notify(conn, skb); 2939 break; 2940 2941 default: 2942 BT_DBG("Unknown command code 0x%2.2x", code); 2943 reason = SMP_CMD_NOTSUPP; 2944 goto done; 2945 } 2946 2947 done: 2948 if (!err) { 2949 if (reason) 2950 smp_failure(conn, reason); 2951 kfree_skb(skb); 2952 } 2953 2954 return err; 2955 2956 drop: 2957 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR", 2958 code, &hcon->dst); 2959 kfree_skb(skb); 2960 return 0; 2961 } 2962 2963 static void smp_teardown_cb(struct l2cap_chan *chan, int err) 2964 { 2965 struct l2cap_conn *conn = chan->conn; 2966 2967 BT_DBG("chan %p", chan); 2968 2969 if (chan->data) 2970 smp_chan_destroy(conn); 2971 2972 conn->smp = NULL; 2973 l2cap_chan_put(chan); 2974 } 2975 2976 static void bredr_pairing(struct l2cap_chan *chan) 2977 { 2978 struct l2cap_conn *conn = chan->conn; 2979 struct hci_conn *hcon = conn->hcon; 2980 struct hci_dev *hdev = hcon->hdev; 2981 struct smp_cmd_pairing req; 2982 struct smp_chan *smp; 2983 2984 BT_DBG("chan %p", chan); 2985 2986 /* Only new pairings are interesting */ 2987 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 2988 return; 2989 2990 /* Don't bother if we're not encrypted */ 2991 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 2992 return; 2993 2994 /* Only master may initiate SMP over BR/EDR */ 2995 if (hcon->role != HCI_ROLE_MASTER) 2996 return; 2997 2998 /* Secure Connections support must be enabled */ 2999 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 3000 return; 3001 3002 /* BR/EDR must use Secure Connections for SMP */ 3003 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 3004 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3005 return; 3006 3007 /* If our LE support is not enabled don't do anything */ 3008 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 3009 return; 3010 3011 /* Don't bother if remote LE support is not enabled */ 3012 if (!lmp_host_le_capable(hcon)) 3013 return; 3014 3015 /* Remote must support SMP fixed chan for BR/EDR */ 3016 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 3017 return; 3018 3019 /* Don't bother if SMP is already ongoing */ 3020 if (chan->data) 3021 return; 3022 3023 smp = smp_chan_create(conn); 3024 if (!smp) { 3025 bt_dev_err(hdev, "unable to create SMP context for BR/EDR"); 3026 return; 3027 } 3028 3029 set_bit(SMP_FLAG_SC, &smp->flags); 3030 3031 BT_DBG("%s starting SMP over BR/EDR", hdev->name); 3032 3033 /* Prepare and send the BR/EDR SMP Pairing Request */ 3034 build_bredr_pairing_cmd(smp, &req, NULL); 3035 3036 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3037 memcpy(&smp->preq[1], &req, sizeof(req)); 3038 3039 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3040 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3041 } 3042 3043 static void smp_resume_cb(struct l2cap_chan *chan) 3044 { 3045 struct smp_chan *smp = chan->data; 3046 struct l2cap_conn *conn = chan->conn; 3047 struct hci_conn *hcon = conn->hcon; 3048 3049 BT_DBG("chan %p", chan); 3050 3051 if (hcon->type == ACL_LINK) { 3052 bredr_pairing(chan); 3053 return; 3054 } 3055 3056 if (!smp) 3057 return; 3058 3059 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3060 return; 3061 3062 cancel_delayed_work(&smp->security_timer); 3063 3064 smp_distribute_keys(smp); 3065 } 3066 3067 static void smp_ready_cb(struct l2cap_chan *chan) 3068 { 3069 struct l2cap_conn *conn = chan->conn; 3070 struct hci_conn *hcon = conn->hcon; 3071 3072 BT_DBG("chan %p", chan); 3073 3074 /* No need to call l2cap_chan_hold() here since we already own 3075 * the reference taken in smp_new_conn_cb(). This is just the 3076 * first time that we tie it to a specific pointer. The code in 3077 * l2cap_core.c ensures that there's no risk this function wont 3078 * get called if smp_new_conn_cb was previously called. 3079 */ 3080 conn->smp = chan; 3081 3082 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3083 bredr_pairing(chan); 3084 } 3085 3086 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3087 { 3088 int err; 3089 3090 BT_DBG("chan %p", chan); 3091 3092 err = smp_sig_channel(chan, skb); 3093 if (err) { 3094 struct smp_chan *smp = chan->data; 3095 3096 if (smp) 3097 cancel_delayed_work_sync(&smp->security_timer); 3098 3099 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3100 } 3101 3102 return err; 3103 } 3104 3105 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3106 unsigned long hdr_len, 3107 unsigned long len, int nb) 3108 { 3109 struct sk_buff *skb; 3110 3111 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3112 if (!skb) 3113 return ERR_PTR(-ENOMEM); 3114 3115 skb->priority = HCI_PRIO_MAX; 3116 bt_cb(skb)->l2cap.chan = chan; 3117 3118 return skb; 3119 } 3120 3121 static const struct l2cap_ops smp_chan_ops = { 3122 .name = "Security Manager", 3123 .ready = smp_ready_cb, 3124 .recv = smp_recv_cb, 3125 .alloc_skb = smp_alloc_skb_cb, 3126 .teardown = smp_teardown_cb, 3127 .resume = smp_resume_cb, 3128 3129 .new_connection = l2cap_chan_no_new_connection, 3130 .state_change = l2cap_chan_no_state_change, 3131 .close = l2cap_chan_no_close, 3132 .defer = l2cap_chan_no_defer, 3133 .suspend = l2cap_chan_no_suspend, 3134 .set_shutdown = l2cap_chan_no_set_shutdown, 3135 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3136 }; 3137 3138 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3139 { 3140 struct l2cap_chan *chan; 3141 3142 BT_DBG("pchan %p", pchan); 3143 3144 chan = l2cap_chan_create(); 3145 if (!chan) 3146 return NULL; 3147 3148 chan->chan_type = pchan->chan_type; 3149 chan->ops = &smp_chan_ops; 3150 chan->scid = pchan->scid; 3151 chan->dcid = chan->scid; 3152 chan->imtu = pchan->imtu; 3153 chan->omtu = pchan->omtu; 3154 chan->mode = pchan->mode; 3155 3156 /* Other L2CAP channels may request SMP routines in order to 3157 * change the security level. This means that the SMP channel 3158 * lock must be considered in its own category to avoid lockdep 3159 * warnings. 3160 */ 3161 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3162 3163 BT_DBG("created chan %p", chan); 3164 3165 return chan; 3166 } 3167 3168 static const struct l2cap_ops smp_root_chan_ops = { 3169 .name = "Security Manager Root", 3170 .new_connection = smp_new_conn_cb, 3171 3172 /* None of these are implemented for the root channel */ 3173 .close = l2cap_chan_no_close, 3174 .alloc_skb = l2cap_chan_no_alloc_skb, 3175 .recv = l2cap_chan_no_recv, 3176 .state_change = l2cap_chan_no_state_change, 3177 .teardown = l2cap_chan_no_teardown, 3178 .ready = l2cap_chan_no_ready, 3179 .defer = l2cap_chan_no_defer, 3180 .suspend = l2cap_chan_no_suspend, 3181 .resume = l2cap_chan_no_resume, 3182 .set_shutdown = l2cap_chan_no_set_shutdown, 3183 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3184 }; 3185 3186 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3187 { 3188 struct l2cap_chan *chan; 3189 struct smp_dev *smp; 3190 struct crypto_cipher *tfm_aes; 3191 struct crypto_shash *tfm_cmac; 3192 struct crypto_kpp *tfm_ecdh; 3193 3194 if (cid == L2CAP_CID_SMP_BREDR) { 3195 smp = NULL; 3196 goto create_chan; 3197 } 3198 3199 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3200 if (!smp) 3201 return ERR_PTR(-ENOMEM); 3202 3203 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 3204 if (IS_ERR(tfm_aes)) { 3205 BT_ERR("Unable to create AES crypto context"); 3206 kzfree(smp); 3207 return ERR_CAST(tfm_aes); 3208 } 3209 3210 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3211 if (IS_ERR(tfm_cmac)) { 3212 BT_ERR("Unable to create CMAC crypto context"); 3213 crypto_free_cipher(tfm_aes); 3214 kzfree(smp); 3215 return ERR_CAST(tfm_cmac); 3216 } 3217 3218 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 3219 if (IS_ERR(tfm_ecdh)) { 3220 BT_ERR("Unable to create ECDH crypto context"); 3221 crypto_free_shash(tfm_cmac); 3222 crypto_free_cipher(tfm_aes); 3223 kzfree(smp); 3224 return ERR_CAST(tfm_ecdh); 3225 } 3226 3227 smp->tfm_aes = tfm_aes; 3228 smp->tfm_cmac = tfm_cmac; 3229 smp->tfm_ecdh = tfm_ecdh; 3230 smp->min_key_size = SMP_MIN_ENC_KEY_SIZE; 3231 smp->max_key_size = SMP_MAX_ENC_KEY_SIZE; 3232 3233 create_chan: 3234 chan = l2cap_chan_create(); 3235 if (!chan) { 3236 if (smp) { 3237 crypto_free_cipher(smp->tfm_aes); 3238 crypto_free_shash(smp->tfm_cmac); 3239 crypto_free_kpp(smp->tfm_ecdh); 3240 kzfree(smp); 3241 } 3242 return ERR_PTR(-ENOMEM); 3243 } 3244 3245 chan->data = smp; 3246 3247 l2cap_add_scid(chan, cid); 3248 3249 l2cap_chan_set_defaults(chan); 3250 3251 if (cid == L2CAP_CID_SMP) { 3252 u8 bdaddr_type; 3253 3254 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3255 3256 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3257 chan->src_type = BDADDR_LE_PUBLIC; 3258 else 3259 chan->src_type = BDADDR_LE_RANDOM; 3260 } else { 3261 bacpy(&chan->src, &hdev->bdaddr); 3262 chan->src_type = BDADDR_BREDR; 3263 } 3264 3265 chan->state = BT_LISTEN; 3266 chan->mode = L2CAP_MODE_BASIC; 3267 chan->imtu = L2CAP_DEFAULT_MTU; 3268 chan->ops = &smp_root_chan_ops; 3269 3270 /* Set correct nesting level for a parent/listening channel */ 3271 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3272 3273 return chan; 3274 } 3275 3276 static void smp_del_chan(struct l2cap_chan *chan) 3277 { 3278 struct smp_dev *smp; 3279 3280 BT_DBG("chan %p", chan); 3281 3282 smp = chan->data; 3283 if (smp) { 3284 chan->data = NULL; 3285 crypto_free_cipher(smp->tfm_aes); 3286 crypto_free_shash(smp->tfm_cmac); 3287 crypto_free_kpp(smp->tfm_ecdh); 3288 kzfree(smp); 3289 } 3290 3291 l2cap_chan_put(chan); 3292 } 3293 3294 static ssize_t force_bredr_smp_read(struct file *file, 3295 char __user *user_buf, 3296 size_t count, loff_t *ppos) 3297 { 3298 struct hci_dev *hdev = file->private_data; 3299 char buf[3]; 3300 3301 buf[0] = hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP) ? 'Y': 'N'; 3302 buf[1] = '\n'; 3303 buf[2] = '\0'; 3304 return simple_read_from_buffer(user_buf, count, ppos, buf, 2); 3305 } 3306 3307 static ssize_t force_bredr_smp_write(struct file *file, 3308 const char __user *user_buf, 3309 size_t count, loff_t *ppos) 3310 { 3311 struct hci_dev *hdev = file->private_data; 3312 char buf[32]; 3313 size_t buf_size = min(count, (sizeof(buf)-1)); 3314 bool enable; 3315 3316 if (copy_from_user(buf, user_buf, buf_size)) 3317 return -EFAULT; 3318 3319 buf[buf_size] = '\0'; 3320 if (strtobool(buf, &enable)) 3321 return -EINVAL; 3322 3323 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3324 return -EALREADY; 3325 3326 if (enable) { 3327 struct l2cap_chan *chan; 3328 3329 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3330 if (IS_ERR(chan)) 3331 return PTR_ERR(chan); 3332 3333 hdev->smp_bredr_data = chan; 3334 } else { 3335 struct l2cap_chan *chan; 3336 3337 chan = hdev->smp_bredr_data; 3338 hdev->smp_bredr_data = NULL; 3339 smp_del_chan(chan); 3340 } 3341 3342 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3343 3344 return count; 3345 } 3346 3347 static const struct file_operations force_bredr_smp_fops = { 3348 .open = simple_open, 3349 .read = force_bredr_smp_read, 3350 .write = force_bredr_smp_write, 3351 .llseek = default_llseek, 3352 }; 3353 3354 static ssize_t le_min_key_size_read(struct file *file, 3355 char __user *user_buf, 3356 size_t count, loff_t *ppos) 3357 { 3358 struct hci_dev *hdev = file->private_data; 3359 char buf[4]; 3360 3361 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->min_key_size); 3362 3363 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); 3364 } 3365 3366 static ssize_t le_min_key_size_write(struct file *file, 3367 const char __user *user_buf, 3368 size_t count, loff_t *ppos) 3369 { 3370 struct hci_dev *hdev = file->private_data; 3371 char buf[32]; 3372 size_t buf_size = min(count, (sizeof(buf) - 1)); 3373 u8 key_size; 3374 3375 if (copy_from_user(buf, user_buf, buf_size)) 3376 return -EFAULT; 3377 3378 buf[buf_size] = '\0'; 3379 3380 sscanf(buf, "%hhu", &key_size); 3381 3382 if (key_size > SMP_DEV(hdev)->max_key_size || 3383 key_size < SMP_MIN_ENC_KEY_SIZE) 3384 return -EINVAL; 3385 3386 SMP_DEV(hdev)->min_key_size = key_size; 3387 3388 return count; 3389 } 3390 3391 static const struct file_operations le_min_key_size_fops = { 3392 .open = simple_open, 3393 .read = le_min_key_size_read, 3394 .write = le_min_key_size_write, 3395 .llseek = default_llseek, 3396 }; 3397 3398 static ssize_t le_max_key_size_read(struct file *file, 3399 char __user *user_buf, 3400 size_t count, loff_t *ppos) 3401 { 3402 struct hci_dev *hdev = file->private_data; 3403 char buf[4]; 3404 3405 snprintf(buf, sizeof(buf), "%2u\n", SMP_DEV(hdev)->max_key_size); 3406 3407 return simple_read_from_buffer(user_buf, count, ppos, buf, strlen(buf)); 3408 } 3409 3410 static ssize_t le_max_key_size_write(struct file *file, 3411 const char __user *user_buf, 3412 size_t count, loff_t *ppos) 3413 { 3414 struct hci_dev *hdev = file->private_data; 3415 char buf[32]; 3416 size_t buf_size = min(count, (sizeof(buf) - 1)); 3417 u8 key_size; 3418 3419 if (copy_from_user(buf, user_buf, buf_size)) 3420 return -EFAULT; 3421 3422 buf[buf_size] = '\0'; 3423 3424 sscanf(buf, "%hhu", &key_size); 3425 3426 if (key_size > SMP_MAX_ENC_KEY_SIZE || 3427 key_size < SMP_DEV(hdev)->min_key_size) 3428 return -EINVAL; 3429 3430 SMP_DEV(hdev)->max_key_size = key_size; 3431 3432 return count; 3433 } 3434 3435 static const struct file_operations le_max_key_size_fops = { 3436 .open = simple_open, 3437 .read = le_max_key_size_read, 3438 .write = le_max_key_size_write, 3439 .llseek = default_llseek, 3440 }; 3441 3442 int smp_register(struct hci_dev *hdev) 3443 { 3444 struct l2cap_chan *chan; 3445 3446 BT_DBG("%s", hdev->name); 3447 3448 /* If the controller does not support Low Energy operation, then 3449 * there is also no need to register any SMP channel. 3450 */ 3451 if (!lmp_le_capable(hdev)) 3452 return 0; 3453 3454 if (WARN_ON(hdev->smp_data)) { 3455 chan = hdev->smp_data; 3456 hdev->smp_data = NULL; 3457 smp_del_chan(chan); 3458 } 3459 3460 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3461 if (IS_ERR(chan)) 3462 return PTR_ERR(chan); 3463 3464 hdev->smp_data = chan; 3465 3466 debugfs_create_file("le_min_key_size", 0644, hdev->debugfs, hdev, 3467 &le_min_key_size_fops); 3468 debugfs_create_file("le_max_key_size", 0644, hdev->debugfs, hdev, 3469 &le_max_key_size_fops); 3470 3471 /* If the controller does not support BR/EDR Secure Connections 3472 * feature, then the BR/EDR SMP channel shall not be present. 3473 * 3474 * To test this with Bluetooth 4.0 controllers, create a debugfs 3475 * switch that allows forcing BR/EDR SMP support and accepting 3476 * cross-transport pairing on non-AES encrypted connections. 3477 */ 3478 if (!lmp_sc_capable(hdev)) { 3479 debugfs_create_file("force_bredr_smp", 0644, hdev->debugfs, 3480 hdev, &force_bredr_smp_fops); 3481 3482 /* Flag can be already set here (due to power toggle) */ 3483 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3484 return 0; 3485 } 3486 3487 if (WARN_ON(hdev->smp_bredr_data)) { 3488 chan = hdev->smp_bredr_data; 3489 hdev->smp_bredr_data = NULL; 3490 smp_del_chan(chan); 3491 } 3492 3493 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3494 if (IS_ERR(chan)) { 3495 int err = PTR_ERR(chan); 3496 chan = hdev->smp_data; 3497 hdev->smp_data = NULL; 3498 smp_del_chan(chan); 3499 return err; 3500 } 3501 3502 hdev->smp_bredr_data = chan; 3503 3504 return 0; 3505 } 3506 3507 void smp_unregister(struct hci_dev *hdev) 3508 { 3509 struct l2cap_chan *chan; 3510 3511 if (hdev->smp_bredr_data) { 3512 chan = hdev->smp_bredr_data; 3513 hdev->smp_bredr_data = NULL; 3514 smp_del_chan(chan); 3515 } 3516 3517 if (hdev->smp_data) { 3518 chan = hdev->smp_data; 3519 hdev->smp_data = NULL; 3520 smp_del_chan(chan); 3521 } 3522 } 3523 3524 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3525 3526 static int __init test_debug_key(struct crypto_kpp *tfm_ecdh) 3527 { 3528 u8 pk[64]; 3529 int err; 3530 3531 err = set_ecdh_privkey(tfm_ecdh, debug_sk); 3532 if (err) 3533 return err; 3534 3535 err = generate_ecdh_public_key(tfm_ecdh, pk); 3536 if (err) 3537 return err; 3538 3539 if (crypto_memneq(pk, debug_pk, 64)) 3540 return -EINVAL; 3541 3542 return 0; 3543 } 3544 3545 static int __init test_ah(struct crypto_cipher *tfm_aes) 3546 { 3547 const u8 irk[16] = { 3548 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3549 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3550 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3551 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3552 u8 res[3]; 3553 int err; 3554 3555 err = smp_ah(tfm_aes, irk, r, res); 3556 if (err) 3557 return err; 3558 3559 if (crypto_memneq(res, exp, 3)) 3560 return -EINVAL; 3561 3562 return 0; 3563 } 3564 3565 static int __init test_c1(struct crypto_cipher *tfm_aes) 3566 { 3567 const u8 k[16] = { 3568 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3569 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3570 const u8 r[16] = { 3571 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3572 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3573 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3574 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3575 const u8 _iat = 0x01; 3576 const u8 _rat = 0x00; 3577 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3578 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3579 const u8 exp[16] = { 3580 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3581 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3582 u8 res[16]; 3583 int err; 3584 3585 err = smp_c1(tfm_aes, k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3586 if (err) 3587 return err; 3588 3589 if (crypto_memneq(res, exp, 16)) 3590 return -EINVAL; 3591 3592 return 0; 3593 } 3594 3595 static int __init test_s1(struct crypto_cipher *tfm_aes) 3596 { 3597 const u8 k[16] = { 3598 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3599 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3600 const u8 r1[16] = { 3601 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3602 const u8 r2[16] = { 3603 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3604 const u8 exp[16] = { 3605 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3606 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3607 u8 res[16]; 3608 int err; 3609 3610 err = smp_s1(tfm_aes, k, r1, r2, res); 3611 if (err) 3612 return err; 3613 3614 if (crypto_memneq(res, exp, 16)) 3615 return -EINVAL; 3616 3617 return 0; 3618 } 3619 3620 static int __init test_f4(struct crypto_shash *tfm_cmac) 3621 { 3622 const u8 u[32] = { 3623 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3624 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3625 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3626 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3627 const u8 v[32] = { 3628 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3629 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3630 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3631 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3632 const u8 x[16] = { 3633 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3634 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3635 const u8 z = 0x00; 3636 const u8 exp[16] = { 3637 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3638 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3639 u8 res[16]; 3640 int err; 3641 3642 err = smp_f4(tfm_cmac, u, v, x, z, res); 3643 if (err) 3644 return err; 3645 3646 if (crypto_memneq(res, exp, 16)) 3647 return -EINVAL; 3648 3649 return 0; 3650 } 3651 3652 static int __init test_f5(struct crypto_shash *tfm_cmac) 3653 { 3654 const u8 w[32] = { 3655 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3656 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3657 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3658 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3659 const u8 n1[16] = { 3660 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3661 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3662 const u8 n2[16] = { 3663 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3664 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3665 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3666 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3667 const u8 exp_ltk[16] = { 3668 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3669 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3670 const u8 exp_mackey[16] = { 3671 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3672 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3673 u8 mackey[16], ltk[16]; 3674 int err; 3675 3676 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3677 if (err) 3678 return err; 3679 3680 if (crypto_memneq(mackey, exp_mackey, 16)) 3681 return -EINVAL; 3682 3683 if (crypto_memneq(ltk, exp_ltk, 16)) 3684 return -EINVAL; 3685 3686 return 0; 3687 } 3688 3689 static int __init test_f6(struct crypto_shash *tfm_cmac) 3690 { 3691 const u8 w[16] = { 3692 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3693 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3694 const u8 n1[16] = { 3695 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3696 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3697 const u8 n2[16] = { 3698 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3699 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3700 const u8 r[16] = { 3701 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3702 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3703 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3704 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3705 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3706 const u8 exp[16] = { 3707 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3708 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3709 u8 res[16]; 3710 int err; 3711 3712 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3713 if (err) 3714 return err; 3715 3716 if (crypto_memneq(res, exp, 16)) 3717 return -EINVAL; 3718 3719 return 0; 3720 } 3721 3722 static int __init test_g2(struct crypto_shash *tfm_cmac) 3723 { 3724 const u8 u[32] = { 3725 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3726 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3727 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3728 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3729 const u8 v[32] = { 3730 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3731 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3732 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3733 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3734 const u8 x[16] = { 3735 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3736 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3737 const u8 y[16] = { 3738 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3739 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3740 const u32 exp_val = 0x2f9ed5ba % 1000000; 3741 u32 val; 3742 int err; 3743 3744 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3745 if (err) 3746 return err; 3747 3748 if (val != exp_val) 3749 return -EINVAL; 3750 3751 return 0; 3752 } 3753 3754 static int __init test_h6(struct crypto_shash *tfm_cmac) 3755 { 3756 const u8 w[16] = { 3757 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3758 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3759 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3760 const u8 exp[16] = { 3761 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3762 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3763 u8 res[16]; 3764 int err; 3765 3766 err = smp_h6(tfm_cmac, w, key_id, res); 3767 if (err) 3768 return err; 3769 3770 if (crypto_memneq(res, exp, 16)) 3771 return -EINVAL; 3772 3773 return 0; 3774 } 3775 3776 static char test_smp_buffer[32]; 3777 3778 static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3779 size_t count, loff_t *ppos) 3780 { 3781 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3782 strlen(test_smp_buffer)); 3783 } 3784 3785 static const struct file_operations test_smp_fops = { 3786 .open = simple_open, 3787 .read = test_smp_read, 3788 .llseek = default_llseek, 3789 }; 3790 3791 static int __init run_selftests(struct crypto_cipher *tfm_aes, 3792 struct crypto_shash *tfm_cmac, 3793 struct crypto_kpp *tfm_ecdh) 3794 { 3795 ktime_t calltime, delta, rettime; 3796 unsigned long long duration; 3797 int err; 3798 3799 calltime = ktime_get(); 3800 3801 err = test_debug_key(tfm_ecdh); 3802 if (err) { 3803 BT_ERR("debug_key test failed"); 3804 goto done; 3805 } 3806 3807 err = test_ah(tfm_aes); 3808 if (err) { 3809 BT_ERR("smp_ah test failed"); 3810 goto done; 3811 } 3812 3813 err = test_c1(tfm_aes); 3814 if (err) { 3815 BT_ERR("smp_c1 test failed"); 3816 goto done; 3817 } 3818 3819 err = test_s1(tfm_aes); 3820 if (err) { 3821 BT_ERR("smp_s1 test failed"); 3822 goto done; 3823 } 3824 3825 err = test_f4(tfm_cmac); 3826 if (err) { 3827 BT_ERR("smp_f4 test failed"); 3828 goto done; 3829 } 3830 3831 err = test_f5(tfm_cmac); 3832 if (err) { 3833 BT_ERR("smp_f5 test failed"); 3834 goto done; 3835 } 3836 3837 err = test_f6(tfm_cmac); 3838 if (err) { 3839 BT_ERR("smp_f6 test failed"); 3840 goto done; 3841 } 3842 3843 err = test_g2(tfm_cmac); 3844 if (err) { 3845 BT_ERR("smp_g2 test failed"); 3846 goto done; 3847 } 3848 3849 err = test_h6(tfm_cmac); 3850 if (err) { 3851 BT_ERR("smp_h6 test failed"); 3852 goto done; 3853 } 3854 3855 rettime = ktime_get(); 3856 delta = ktime_sub(rettime, calltime); 3857 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3858 3859 BT_INFO("SMP test passed in %llu usecs", duration); 3860 3861 done: 3862 if (!err) 3863 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3864 "PASS (%llu usecs)\n", duration); 3865 else 3866 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3867 3868 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3869 &test_smp_fops); 3870 3871 return err; 3872 } 3873 3874 int __init bt_selftest_smp(void) 3875 { 3876 struct crypto_cipher *tfm_aes; 3877 struct crypto_shash *tfm_cmac; 3878 struct crypto_kpp *tfm_ecdh; 3879 int err; 3880 3881 tfm_aes = crypto_alloc_cipher("aes", 0, CRYPTO_ALG_ASYNC); 3882 if (IS_ERR(tfm_aes)) { 3883 BT_ERR("Unable to create AES crypto context"); 3884 return PTR_ERR(tfm_aes); 3885 } 3886 3887 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, CRYPTO_ALG_ASYNC); 3888 if (IS_ERR(tfm_cmac)) { 3889 BT_ERR("Unable to create CMAC crypto context"); 3890 crypto_free_cipher(tfm_aes); 3891 return PTR_ERR(tfm_cmac); 3892 } 3893 3894 tfm_ecdh = crypto_alloc_kpp("ecdh", CRYPTO_ALG_INTERNAL, 0); 3895 if (IS_ERR(tfm_ecdh)) { 3896 BT_ERR("Unable to create ECDH crypto context"); 3897 crypto_free_shash(tfm_cmac); 3898 crypto_free_cipher(tfm_aes); 3899 return PTR_ERR(tfm_ecdh); 3900 } 3901 3902 err = run_selftests(tfm_aes, tfm_cmac, tfm_ecdh); 3903 3904 crypto_free_shash(tfm_cmac); 3905 crypto_free_cipher(tfm_aes); 3906 crypto_free_kpp(tfm_ecdh); 3907 3908 return err; 3909 } 3910 3911 #endif 3912