1 /* 2 BlueZ - Bluetooth protocol stack for Linux 3 Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License version 2 as 7 published by the Free Software Foundation; 8 9 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 10 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 11 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. 12 IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY 13 CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES 14 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 18 ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS, 19 COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS 20 SOFTWARE IS DISCLAIMED. 21 */ 22 23 #include <linux/debugfs.h> 24 #include <linux/scatterlist.h> 25 #include <linux/crypto.h> 26 #include <crypto/aes.h> 27 #include <crypto/algapi.h> 28 #include <crypto/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 bool local_oob; 87 u8 local_pk[64]; 88 u8 local_rand[16]; 89 bool debug_key; 90 91 struct crypto_shash *tfm_cmac; 92 struct crypto_kpp *tfm_ecdh; 93 }; 94 95 struct smp_chan { 96 struct l2cap_conn *conn; 97 struct delayed_work security_timer; 98 unsigned long allow_cmd; /* Bitmask of allowed commands */ 99 100 u8 preq[7]; /* SMP Pairing Request */ 101 u8 prsp[7]; /* SMP Pairing Response */ 102 u8 prnd[16]; /* SMP Pairing Random (local) */ 103 u8 rrnd[16]; /* SMP Pairing Random (remote) */ 104 u8 pcnf[16]; /* SMP Pairing Confirm */ 105 u8 tk[16]; /* SMP Temporary Key */ 106 u8 rr[16]; /* Remote OOB ra/rb value */ 107 u8 lr[16]; /* Local OOB ra/rb value */ 108 u8 enc_key_size; 109 u8 remote_key_dist; 110 bdaddr_t id_addr; 111 u8 id_addr_type; 112 u8 irk[16]; 113 struct smp_csrk *csrk; 114 struct smp_csrk *slave_csrk; 115 struct smp_ltk *ltk; 116 struct smp_ltk *slave_ltk; 117 struct smp_irk *remote_irk; 118 u8 *link_key; 119 unsigned long flags; 120 u8 method; 121 u8 passkey_round; 122 123 /* Secure Connections variables */ 124 u8 local_pk[64]; 125 u8 remote_pk[64]; 126 u8 dhkey[32]; 127 u8 mackey[16]; 128 129 struct crypto_shash *tfm_cmac; 130 struct crypto_kpp *tfm_ecdh; 131 }; 132 133 /* These debug key values are defined in the SMP section of the core 134 * specification. debug_pk is the public debug key and debug_sk the 135 * private debug key. 136 */ 137 static const u8 debug_pk[64] = { 138 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 139 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 140 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 141 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20, 142 143 0x8b, 0xd2, 0x89, 0x15, 0xd0, 0x8e, 0x1c, 0x74, 144 0x24, 0x30, 0xed, 0x8f, 0xc2, 0x45, 0x63, 0x76, 145 0x5c, 0x15, 0x52, 0x5a, 0xbf, 0x9a, 0x32, 0x63, 146 0x6d, 0xeb, 0x2a, 0x65, 0x49, 0x9c, 0x80, 0xdc, 147 }; 148 149 static const u8 debug_sk[32] = { 150 0xbd, 0x1a, 0x3c, 0xcd, 0xa6, 0xb8, 0x99, 0x58, 151 0x99, 0xb7, 0x40, 0xeb, 0x7b, 0x60, 0xff, 0x4a, 152 0x50, 0x3f, 0x10, 0xd2, 0xe3, 0xb3, 0xc9, 0x74, 153 0x38, 0x5f, 0xc5, 0xa3, 0xd4, 0xf6, 0x49, 0x3f, 154 }; 155 156 static inline void swap_buf(const u8 *src, u8 *dst, size_t len) 157 { 158 size_t i; 159 160 for (i = 0; i < len; i++) 161 dst[len - 1 - i] = src[i]; 162 } 163 164 /* The following functions map to the LE SC SMP crypto functions 165 * AES-CMAC, f4, f5, f6, g2 and h6. 166 */ 167 168 static int aes_cmac(struct crypto_shash *tfm, const u8 k[16], const u8 *m, 169 size_t len, u8 mac[16]) 170 { 171 uint8_t tmp[16], mac_msb[16], msg_msb[CMAC_MSG_MAX]; 172 int err; 173 174 if (len > CMAC_MSG_MAX) 175 return -EFBIG; 176 177 if (!tfm) { 178 BT_ERR("tfm %p", tfm); 179 return -EINVAL; 180 } 181 182 /* Swap key and message from LSB to MSB */ 183 swap_buf(k, tmp, 16); 184 swap_buf(m, msg_msb, len); 185 186 SMP_DBG("msg (len %zu) %*phN", len, (int) len, m); 187 SMP_DBG("key %16phN", k); 188 189 err = crypto_shash_setkey(tfm, tmp, 16); 190 if (err) { 191 BT_ERR("cipher setkey failed: %d", err); 192 return err; 193 } 194 195 err = crypto_shash_tfm_digest(tfm, msg_msb, len, mac_msb); 196 if (err) { 197 BT_ERR("Hash computation error %d", err); 198 return err; 199 } 200 201 swap_buf(mac_msb, mac, 16); 202 203 SMP_DBG("mac %16phN", mac); 204 205 return 0; 206 } 207 208 static int smp_f4(struct crypto_shash *tfm_cmac, const u8 u[32], 209 const u8 v[32], const u8 x[16], u8 z, u8 res[16]) 210 { 211 u8 m[65]; 212 int err; 213 214 SMP_DBG("u %32phN", u); 215 SMP_DBG("v %32phN", v); 216 SMP_DBG("x %16phN z %02x", x, z); 217 218 m[0] = z; 219 memcpy(m + 1, v, 32); 220 memcpy(m + 33, u, 32); 221 222 err = aes_cmac(tfm_cmac, x, m, sizeof(m), res); 223 if (err) 224 return err; 225 226 SMP_DBG("res %16phN", res); 227 228 return err; 229 } 230 231 static int smp_f5(struct crypto_shash *tfm_cmac, const u8 w[32], 232 const u8 n1[16], const u8 n2[16], const u8 a1[7], 233 const u8 a2[7], u8 mackey[16], u8 ltk[16]) 234 { 235 /* The btle, salt and length "magic" values are as defined in 236 * the SMP section of the Bluetooth core specification. In ASCII 237 * the btle value ends up being 'btle'. The salt is just a 238 * random number whereas length is the value 256 in little 239 * endian format. 240 */ 241 const u8 btle[4] = { 0x65, 0x6c, 0x74, 0x62 }; 242 const u8 salt[16] = { 0xbe, 0x83, 0x60, 0x5a, 0xdb, 0x0b, 0x37, 0x60, 243 0x38, 0xa5, 0xf5, 0xaa, 0x91, 0x83, 0x88, 0x6c }; 244 const u8 length[2] = { 0x00, 0x01 }; 245 u8 m[53], t[16]; 246 int err; 247 248 SMP_DBG("w %32phN", w); 249 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 250 SMP_DBG("a1 %7phN a2 %7phN", a1, a2); 251 252 err = aes_cmac(tfm_cmac, salt, w, 32, t); 253 if (err) 254 return err; 255 256 SMP_DBG("t %16phN", t); 257 258 memcpy(m, length, 2); 259 memcpy(m + 2, a2, 7); 260 memcpy(m + 9, a1, 7); 261 memcpy(m + 16, n2, 16); 262 memcpy(m + 32, n1, 16); 263 memcpy(m + 48, btle, 4); 264 265 m[52] = 0; /* Counter */ 266 267 err = aes_cmac(tfm_cmac, t, m, sizeof(m), mackey); 268 if (err) 269 return err; 270 271 SMP_DBG("mackey %16phN", mackey); 272 273 m[52] = 1; /* Counter */ 274 275 err = aes_cmac(tfm_cmac, t, m, sizeof(m), ltk); 276 if (err) 277 return err; 278 279 SMP_DBG("ltk %16phN", ltk); 280 281 return 0; 282 } 283 284 static int smp_f6(struct crypto_shash *tfm_cmac, const u8 w[16], 285 const u8 n1[16], const u8 n2[16], const u8 r[16], 286 const u8 io_cap[3], const u8 a1[7], const u8 a2[7], 287 u8 res[16]) 288 { 289 u8 m[65]; 290 int err; 291 292 SMP_DBG("w %16phN", w); 293 SMP_DBG("n1 %16phN n2 %16phN", n1, n2); 294 SMP_DBG("r %16phN io_cap %3phN a1 %7phN a2 %7phN", r, io_cap, a1, a2); 295 296 memcpy(m, a2, 7); 297 memcpy(m + 7, a1, 7); 298 memcpy(m + 14, io_cap, 3); 299 memcpy(m + 17, r, 16); 300 memcpy(m + 33, n2, 16); 301 memcpy(m + 49, n1, 16); 302 303 err = aes_cmac(tfm_cmac, w, m, sizeof(m), res); 304 if (err) 305 return err; 306 307 SMP_DBG("res %16phN", res); 308 309 return err; 310 } 311 312 static int smp_g2(struct crypto_shash *tfm_cmac, const u8 u[32], const u8 v[32], 313 const u8 x[16], const u8 y[16], u32 *val) 314 { 315 u8 m[80], tmp[16]; 316 int err; 317 318 SMP_DBG("u %32phN", u); 319 SMP_DBG("v %32phN", v); 320 SMP_DBG("x %16phN y %16phN", x, y); 321 322 memcpy(m, y, 16); 323 memcpy(m + 16, v, 32); 324 memcpy(m + 48, u, 32); 325 326 err = aes_cmac(tfm_cmac, x, m, sizeof(m), tmp); 327 if (err) 328 return err; 329 330 *val = get_unaligned_le32(tmp); 331 *val %= 1000000; 332 333 SMP_DBG("val %06u", *val); 334 335 return 0; 336 } 337 338 static int smp_h6(struct crypto_shash *tfm_cmac, const u8 w[16], 339 const u8 key_id[4], u8 res[16]) 340 { 341 int err; 342 343 SMP_DBG("w %16phN key_id %4phN", w, key_id); 344 345 err = aes_cmac(tfm_cmac, w, key_id, 4, res); 346 if (err) 347 return err; 348 349 SMP_DBG("res %16phN", res); 350 351 return err; 352 } 353 354 static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16], 355 const u8 salt[16], u8 res[16]) 356 { 357 int err; 358 359 SMP_DBG("w %16phN salt %16phN", w, salt); 360 361 err = aes_cmac(tfm_cmac, salt, w, 16, res); 362 if (err) 363 return err; 364 365 SMP_DBG("res %16phN", res); 366 367 return err; 368 } 369 370 /* The following functions map to the legacy SMP crypto functions e, c1, 371 * s1 and ah. 372 */ 373 374 static int smp_e(const u8 *k, u8 *r) 375 { 376 struct crypto_aes_ctx ctx; 377 uint8_t tmp[16], data[16]; 378 int err; 379 380 SMP_DBG("k %16phN r %16phN", k, r); 381 382 /* The most significant octet of key corresponds to k[0] */ 383 swap_buf(k, tmp, 16); 384 385 err = aes_expandkey(&ctx, tmp, 16); 386 if (err) { 387 BT_ERR("cipher setkey failed: %d", err); 388 return err; 389 } 390 391 /* Most significant octet of plaintextData corresponds to data[0] */ 392 swap_buf(r, data, 16); 393 394 aes_encrypt(&ctx, data, data); 395 396 /* Most significant octet of encryptedData corresponds to data[0] */ 397 swap_buf(data, r, 16); 398 399 SMP_DBG("r %16phN", r); 400 401 memzero_explicit(&ctx, sizeof (ctx)); 402 return err; 403 } 404 405 static int smp_c1(const u8 k[16], 406 const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat, 407 const bdaddr_t *ia, u8 _rat, const bdaddr_t *ra, u8 res[16]) 408 { 409 u8 p1[16], p2[16]; 410 int err; 411 412 SMP_DBG("k %16phN r %16phN", k, r); 413 SMP_DBG("iat %u ia %6phN rat %u ra %6phN", _iat, ia, _rat, ra); 414 SMP_DBG("preq %7phN pres %7phN", preq, pres); 415 416 memset(p1, 0, 16); 417 418 /* p1 = pres || preq || _rat || _iat */ 419 p1[0] = _iat; 420 p1[1] = _rat; 421 memcpy(p1 + 2, preq, 7); 422 memcpy(p1 + 9, pres, 7); 423 424 SMP_DBG("p1 %16phN", p1); 425 426 /* res = r XOR p1 */ 427 crypto_xor_cpy(res, r, p1, sizeof(p1)); 428 429 /* res = e(k, res) */ 430 err = smp_e(k, res); 431 if (err) { 432 BT_ERR("Encrypt data error"); 433 return err; 434 } 435 436 /* p2 = padding || ia || ra */ 437 memcpy(p2, ra, 6); 438 memcpy(p2 + 6, ia, 6); 439 memset(p2 + 12, 0, 4); 440 441 SMP_DBG("p2 %16phN", p2); 442 443 /* res = res XOR p2 */ 444 crypto_xor(res, p2, sizeof(p2)); 445 446 /* res = e(k, res) */ 447 err = smp_e(k, res); 448 if (err) 449 BT_ERR("Encrypt data error"); 450 451 return err; 452 } 453 454 static int smp_s1(const u8 k[16], 455 const u8 r1[16], const u8 r2[16], u8 _r[16]) 456 { 457 int err; 458 459 /* Just least significant octets from r1 and r2 are considered */ 460 memcpy(_r, r2, 8); 461 memcpy(_r + 8, r1, 8); 462 463 err = smp_e(k, _r); 464 if (err) 465 BT_ERR("Encrypt data error"); 466 467 return err; 468 } 469 470 static int smp_ah(const u8 irk[16], const u8 r[3], u8 res[3]) 471 { 472 u8 _res[16]; 473 int err; 474 475 /* r' = padding || r */ 476 memcpy(_res, r, 3); 477 memset(_res + 3, 0, 13); 478 479 err = smp_e(irk, _res); 480 if (err) { 481 BT_ERR("Encrypt error"); 482 return err; 483 } 484 485 /* The output of the random address function ah is: 486 * ah(k, r) = e(k, r') mod 2^24 487 * The output of the security function e is then truncated to 24 bits 488 * by taking the least significant 24 bits of the output of e as the 489 * result of ah. 490 */ 491 memcpy(res, _res, 3); 492 493 return 0; 494 } 495 496 bool smp_irk_matches(struct hci_dev *hdev, const u8 irk[16], 497 const bdaddr_t *bdaddr) 498 { 499 struct l2cap_chan *chan = hdev->smp_data; 500 u8 hash[3]; 501 int err; 502 503 if (!chan || !chan->data) 504 return false; 505 506 bt_dev_dbg(hdev, "RPA %pMR IRK %*phN", bdaddr, 16, irk); 507 508 err = smp_ah(irk, &bdaddr->b[3], hash); 509 if (err) 510 return false; 511 512 return !crypto_memneq(bdaddr->b, hash, 3); 513 } 514 515 int smp_generate_rpa(struct hci_dev *hdev, const u8 irk[16], bdaddr_t *rpa) 516 { 517 struct l2cap_chan *chan = hdev->smp_data; 518 int err; 519 520 if (!chan || !chan->data) 521 return -EOPNOTSUPP; 522 523 get_random_bytes(&rpa->b[3], 3); 524 525 rpa->b[5] &= 0x3f; /* Clear two most significant bits */ 526 rpa->b[5] |= 0x40; /* Set second most significant bit */ 527 528 err = smp_ah(irk, &rpa->b[3], rpa->b); 529 if (err < 0) 530 return err; 531 532 bt_dev_dbg(hdev, "RPA %pMR", rpa); 533 534 return 0; 535 } 536 537 int smp_generate_oob(struct hci_dev *hdev, u8 hash[16], u8 rand[16]) 538 { 539 struct l2cap_chan *chan = hdev->smp_data; 540 struct smp_dev *smp; 541 int err; 542 543 if (!chan || !chan->data) 544 return -EOPNOTSUPP; 545 546 smp = chan->data; 547 548 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 549 bt_dev_dbg(hdev, "Using debug keys"); 550 err = set_ecdh_privkey(smp->tfm_ecdh, debug_sk); 551 if (err) 552 return err; 553 memcpy(smp->local_pk, debug_pk, 64); 554 smp->debug_key = true; 555 } else { 556 while (true) { 557 /* Generate key pair for Secure Connections */ 558 err = generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk); 559 if (err) 560 return err; 561 562 /* This is unlikely, but we need to check that 563 * we didn't accidentially generate a debug key. 564 */ 565 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 566 break; 567 } 568 smp->debug_key = false; 569 } 570 571 SMP_DBG("OOB Public Key X: %32phN", smp->local_pk); 572 SMP_DBG("OOB Public Key Y: %32phN", smp->local_pk + 32); 573 574 get_random_bytes(smp->local_rand, 16); 575 576 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->local_pk, 577 smp->local_rand, 0, hash); 578 if (err < 0) 579 return err; 580 581 memcpy(rand, smp->local_rand, 16); 582 583 smp->local_oob = true; 584 585 return 0; 586 } 587 588 static void smp_send_cmd(struct l2cap_conn *conn, u8 code, u16 len, void *data) 589 { 590 struct l2cap_chan *chan = conn->smp; 591 struct smp_chan *smp; 592 struct kvec iv[2]; 593 struct msghdr msg; 594 595 if (!chan) 596 return; 597 598 BT_DBG("code 0x%2.2x", code); 599 600 iv[0].iov_base = &code; 601 iv[0].iov_len = 1; 602 603 iv[1].iov_base = data; 604 iv[1].iov_len = len; 605 606 memset(&msg, 0, sizeof(msg)); 607 608 iov_iter_kvec(&msg.msg_iter, WRITE, iv, 2, 1 + len); 609 610 l2cap_chan_send(chan, &msg, 1 + len); 611 612 if (!chan->data) 613 return; 614 615 smp = chan->data; 616 617 cancel_delayed_work_sync(&smp->security_timer); 618 schedule_delayed_work(&smp->security_timer, SMP_TIMEOUT); 619 } 620 621 static u8 authreq_to_seclevel(u8 authreq) 622 { 623 if (authreq & SMP_AUTH_MITM) { 624 if (authreq & SMP_AUTH_SC) 625 return BT_SECURITY_FIPS; 626 else 627 return BT_SECURITY_HIGH; 628 } else { 629 return BT_SECURITY_MEDIUM; 630 } 631 } 632 633 static __u8 seclevel_to_authreq(__u8 sec_level) 634 { 635 switch (sec_level) { 636 case BT_SECURITY_FIPS: 637 case BT_SECURITY_HIGH: 638 return SMP_AUTH_MITM | SMP_AUTH_BONDING; 639 case BT_SECURITY_MEDIUM: 640 return SMP_AUTH_BONDING; 641 default: 642 return SMP_AUTH_NONE; 643 } 644 } 645 646 static void build_pairing_cmd(struct l2cap_conn *conn, 647 struct smp_cmd_pairing *req, 648 struct smp_cmd_pairing *rsp, __u8 authreq) 649 { 650 struct l2cap_chan *chan = conn->smp; 651 struct smp_chan *smp = chan->data; 652 struct hci_conn *hcon = conn->hcon; 653 struct hci_dev *hdev = hcon->hdev; 654 u8 local_dist = 0, remote_dist = 0, oob_flag = SMP_OOB_NOT_PRESENT; 655 656 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 657 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 658 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 659 authreq |= SMP_AUTH_BONDING; 660 } else { 661 authreq &= ~SMP_AUTH_BONDING; 662 } 663 664 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 665 remote_dist |= SMP_DIST_ID_KEY; 666 667 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 668 local_dist |= SMP_DIST_ID_KEY; 669 670 if (hci_dev_test_flag(hdev, HCI_SC_ENABLED) && 671 (authreq & SMP_AUTH_SC)) { 672 struct oob_data *oob_data; 673 u8 bdaddr_type; 674 675 if (hci_dev_test_flag(hdev, HCI_SSP_ENABLED)) { 676 local_dist |= SMP_DIST_LINK_KEY; 677 remote_dist |= SMP_DIST_LINK_KEY; 678 } 679 680 if (hcon->dst_type == ADDR_LE_DEV_PUBLIC) 681 bdaddr_type = BDADDR_LE_PUBLIC; 682 else 683 bdaddr_type = BDADDR_LE_RANDOM; 684 685 oob_data = hci_find_remote_oob_data(hdev, &hcon->dst, 686 bdaddr_type); 687 if (oob_data && oob_data->present) { 688 set_bit(SMP_FLAG_REMOTE_OOB, &smp->flags); 689 oob_flag = SMP_OOB_PRESENT; 690 memcpy(smp->rr, oob_data->rand256, 16); 691 memcpy(smp->pcnf, oob_data->hash256, 16); 692 SMP_DBG("OOB Remote Confirmation: %16phN", smp->pcnf); 693 SMP_DBG("OOB Remote Random: %16phN", smp->rr); 694 } 695 696 } else { 697 authreq &= ~SMP_AUTH_SC; 698 } 699 700 if (rsp == NULL) { 701 req->io_capability = conn->hcon->io_capability; 702 req->oob_flag = oob_flag; 703 req->max_key_size = hdev->le_max_key_size; 704 req->init_key_dist = local_dist; 705 req->resp_key_dist = remote_dist; 706 req->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 707 708 smp->remote_key_dist = remote_dist; 709 return; 710 } 711 712 rsp->io_capability = conn->hcon->io_capability; 713 rsp->oob_flag = oob_flag; 714 rsp->max_key_size = hdev->le_max_key_size; 715 rsp->init_key_dist = req->init_key_dist & remote_dist; 716 rsp->resp_key_dist = req->resp_key_dist & local_dist; 717 rsp->auth_req = (authreq & AUTH_REQ_MASK(hdev)); 718 719 smp->remote_key_dist = rsp->init_key_dist; 720 } 721 722 static u8 check_enc_key_size(struct l2cap_conn *conn, __u8 max_key_size) 723 { 724 struct l2cap_chan *chan = conn->smp; 725 struct hci_dev *hdev = conn->hcon->hdev; 726 struct smp_chan *smp = chan->data; 727 728 if (conn->hcon->pending_sec_level == BT_SECURITY_FIPS && 729 max_key_size != SMP_MAX_ENC_KEY_SIZE) 730 return SMP_ENC_KEY_SIZE; 731 732 if (max_key_size > hdev->le_max_key_size || 733 max_key_size < SMP_MIN_ENC_KEY_SIZE) 734 return SMP_ENC_KEY_SIZE; 735 736 smp->enc_key_size = max_key_size; 737 738 return 0; 739 } 740 741 static void smp_chan_destroy(struct l2cap_conn *conn) 742 { 743 struct l2cap_chan *chan = conn->smp; 744 struct smp_chan *smp = chan->data; 745 struct hci_conn *hcon = conn->hcon; 746 bool complete; 747 748 BUG_ON(!smp); 749 750 cancel_delayed_work_sync(&smp->security_timer); 751 752 complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags); 753 mgmt_smp_complete(hcon, complete); 754 755 kfree_sensitive(smp->csrk); 756 kfree_sensitive(smp->slave_csrk); 757 kfree_sensitive(smp->link_key); 758 759 crypto_free_shash(smp->tfm_cmac); 760 crypto_free_kpp(smp->tfm_ecdh); 761 762 /* Ensure that we don't leave any debug key around if debug key 763 * support hasn't been explicitly enabled. 764 */ 765 if (smp->ltk && smp->ltk->type == SMP_LTK_P256_DEBUG && 766 !hci_dev_test_flag(hcon->hdev, HCI_KEEP_DEBUG_KEYS)) { 767 list_del_rcu(&smp->ltk->list); 768 kfree_rcu(smp->ltk, rcu); 769 smp->ltk = NULL; 770 } 771 772 /* If pairing failed clean up any keys we might have */ 773 if (!complete) { 774 if (smp->ltk) { 775 list_del_rcu(&smp->ltk->list); 776 kfree_rcu(smp->ltk, rcu); 777 } 778 779 if (smp->slave_ltk) { 780 list_del_rcu(&smp->slave_ltk->list); 781 kfree_rcu(smp->slave_ltk, rcu); 782 } 783 784 if (smp->remote_irk) { 785 list_del_rcu(&smp->remote_irk->list); 786 kfree_rcu(smp->remote_irk, rcu); 787 } 788 } 789 790 chan->data = NULL; 791 kfree_sensitive(smp); 792 hci_conn_drop(hcon); 793 } 794 795 static void smp_failure(struct l2cap_conn *conn, u8 reason) 796 { 797 struct hci_conn *hcon = conn->hcon; 798 struct l2cap_chan *chan = conn->smp; 799 800 if (reason) 801 smp_send_cmd(conn, SMP_CMD_PAIRING_FAIL, sizeof(reason), 802 &reason); 803 804 mgmt_auth_failed(hcon, HCI_ERROR_AUTH_FAILURE); 805 806 if (chan->data) 807 smp_chan_destroy(conn); 808 } 809 810 #define JUST_WORKS 0x00 811 #define JUST_CFM 0x01 812 #define REQ_PASSKEY 0x02 813 #define CFM_PASSKEY 0x03 814 #define REQ_OOB 0x04 815 #define DSP_PASSKEY 0x05 816 #define OVERLAP 0xFF 817 818 static const u8 gen_method[5][5] = { 819 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 820 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 821 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 822 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 823 { CFM_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, OVERLAP }, 824 }; 825 826 static const u8 sc_method[5][5] = { 827 { JUST_WORKS, JUST_CFM, REQ_PASSKEY, JUST_WORKS, REQ_PASSKEY }, 828 { JUST_WORKS, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 829 { DSP_PASSKEY, DSP_PASSKEY, REQ_PASSKEY, JUST_WORKS, DSP_PASSKEY }, 830 { JUST_WORKS, JUST_CFM, JUST_WORKS, JUST_WORKS, JUST_CFM }, 831 { DSP_PASSKEY, CFM_PASSKEY, REQ_PASSKEY, JUST_WORKS, CFM_PASSKEY }, 832 }; 833 834 static u8 get_auth_method(struct smp_chan *smp, u8 local_io, u8 remote_io) 835 { 836 /* If either side has unknown io_caps, use JUST_CFM (which gets 837 * converted later to JUST_WORKS if we're initiators. 838 */ 839 if (local_io > SMP_IO_KEYBOARD_DISPLAY || 840 remote_io > SMP_IO_KEYBOARD_DISPLAY) 841 return JUST_CFM; 842 843 if (test_bit(SMP_FLAG_SC, &smp->flags)) 844 return sc_method[remote_io][local_io]; 845 846 return gen_method[remote_io][local_io]; 847 } 848 849 static int tk_request(struct l2cap_conn *conn, u8 remote_oob, u8 auth, 850 u8 local_io, u8 remote_io) 851 { 852 struct hci_conn *hcon = conn->hcon; 853 struct l2cap_chan *chan = conn->smp; 854 struct smp_chan *smp = chan->data; 855 u32 passkey = 0; 856 int ret; 857 858 /* Initialize key for JUST WORKS */ 859 memset(smp->tk, 0, sizeof(smp->tk)); 860 clear_bit(SMP_FLAG_TK_VALID, &smp->flags); 861 862 BT_DBG("tk_request: auth:%d lcl:%d rem:%d", auth, local_io, remote_io); 863 864 /* If neither side wants MITM, either "just" confirm an incoming 865 * request or use just-works for outgoing ones. The JUST_CFM 866 * will be converted to JUST_WORKS if necessary later in this 867 * function. If either side has MITM look up the method from the 868 * table. 869 */ 870 if (!(auth & SMP_AUTH_MITM)) 871 smp->method = JUST_CFM; 872 else 873 smp->method = get_auth_method(smp, local_io, remote_io); 874 875 /* Don't confirm locally initiated pairing attempts */ 876 if (smp->method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, 877 &smp->flags)) 878 smp->method = JUST_WORKS; 879 880 /* Don't bother user space with no IO capabilities */ 881 if (smp->method == JUST_CFM && 882 hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 883 smp->method = JUST_WORKS; 884 885 /* If Just Works, Continue with Zero TK and ask user-space for 886 * confirmation */ 887 if (smp->method == JUST_WORKS) { 888 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 889 hcon->type, 890 hcon->dst_type, 891 passkey, 1); 892 if (ret) 893 return ret; 894 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 895 return 0; 896 } 897 898 /* If this function is used for SC -> legacy fallback we 899 * can only recover the just-works case. 900 */ 901 if (test_bit(SMP_FLAG_SC, &smp->flags)) 902 return -EINVAL; 903 904 /* Not Just Works/Confirm results in MITM Authentication */ 905 if (smp->method != JUST_CFM) { 906 set_bit(SMP_FLAG_MITM_AUTH, &smp->flags); 907 if (hcon->pending_sec_level < BT_SECURITY_HIGH) 908 hcon->pending_sec_level = BT_SECURITY_HIGH; 909 } 910 911 /* If both devices have Keyoard-Display I/O, the master 912 * Confirms and the slave Enters the passkey. 913 */ 914 if (smp->method == OVERLAP) { 915 if (hcon->role == HCI_ROLE_MASTER) 916 smp->method = CFM_PASSKEY; 917 else 918 smp->method = REQ_PASSKEY; 919 } 920 921 /* Generate random passkey. */ 922 if (smp->method == CFM_PASSKEY) { 923 memset(smp->tk, 0, sizeof(smp->tk)); 924 get_random_bytes(&passkey, sizeof(passkey)); 925 passkey %= 1000000; 926 put_unaligned_le32(passkey, smp->tk); 927 BT_DBG("PassKey: %d", passkey); 928 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 929 } 930 931 if (smp->method == REQ_PASSKEY) 932 ret = mgmt_user_passkey_request(hcon->hdev, &hcon->dst, 933 hcon->type, hcon->dst_type); 934 else if (smp->method == JUST_CFM) 935 ret = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, 936 hcon->type, hcon->dst_type, 937 passkey, 1); 938 else 939 ret = mgmt_user_passkey_notify(hcon->hdev, &hcon->dst, 940 hcon->type, hcon->dst_type, 941 passkey, 0); 942 943 return ret; 944 } 945 946 static u8 smp_confirm(struct smp_chan *smp) 947 { 948 struct l2cap_conn *conn = smp->conn; 949 struct smp_cmd_pairing_confirm cp; 950 int ret; 951 952 BT_DBG("conn %p", conn); 953 954 ret = smp_c1(smp->tk, smp->prnd, smp->preq, smp->prsp, 955 conn->hcon->init_addr_type, &conn->hcon->init_addr, 956 conn->hcon->resp_addr_type, &conn->hcon->resp_addr, 957 cp.confirm_val); 958 if (ret) 959 return SMP_UNSPECIFIED; 960 961 clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 962 963 smp_send_cmd(smp->conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cp), &cp); 964 965 if (conn->hcon->out) 966 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 967 else 968 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 969 970 return 0; 971 } 972 973 static u8 smp_random(struct smp_chan *smp) 974 { 975 struct l2cap_conn *conn = smp->conn; 976 struct hci_conn *hcon = conn->hcon; 977 u8 confirm[16]; 978 int ret; 979 980 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 981 982 ret = smp_c1(smp->tk, smp->rrnd, smp->preq, smp->prsp, 983 hcon->init_addr_type, &hcon->init_addr, 984 hcon->resp_addr_type, &hcon->resp_addr, confirm); 985 if (ret) 986 return SMP_UNSPECIFIED; 987 988 if (crypto_memneq(smp->pcnf, confirm, sizeof(smp->pcnf))) { 989 bt_dev_err(hcon->hdev, "pairing failed " 990 "(confirmation values mismatch)"); 991 return SMP_CONFIRM_FAILED; 992 } 993 994 if (hcon->out) { 995 u8 stk[16]; 996 __le64 rand = 0; 997 __le16 ediv = 0; 998 999 smp_s1(smp->tk, smp->rrnd, smp->prnd, stk); 1000 1001 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 1002 return SMP_UNSPECIFIED; 1003 1004 hci_le_start_enc(hcon, ediv, rand, stk, smp->enc_key_size); 1005 hcon->enc_key_size = smp->enc_key_size; 1006 set_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 1007 } else { 1008 u8 stk[16], auth; 1009 __le64 rand = 0; 1010 __le16 ediv = 0; 1011 1012 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 1013 smp->prnd); 1014 1015 smp_s1(smp->tk, smp->prnd, smp->rrnd, stk); 1016 1017 if (hcon->pending_sec_level == BT_SECURITY_HIGH) 1018 auth = 1; 1019 else 1020 auth = 0; 1021 1022 /* Even though there's no _SLAVE suffix this is the 1023 * slave STK we're adding for later lookup (the master 1024 * STK never needs to be stored). 1025 */ 1026 hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1027 SMP_STK, auth, stk, smp->enc_key_size, ediv, rand); 1028 } 1029 1030 return 0; 1031 } 1032 1033 static void smp_notify_keys(struct l2cap_conn *conn) 1034 { 1035 struct l2cap_chan *chan = conn->smp; 1036 struct smp_chan *smp = chan->data; 1037 struct hci_conn *hcon = conn->hcon; 1038 struct hci_dev *hdev = hcon->hdev; 1039 struct smp_cmd_pairing *req = (void *) &smp->preq[1]; 1040 struct smp_cmd_pairing *rsp = (void *) &smp->prsp[1]; 1041 bool persistent; 1042 1043 if (hcon->type == ACL_LINK) { 1044 if (hcon->key_type == HCI_LK_DEBUG_COMBINATION) 1045 persistent = false; 1046 else 1047 persistent = !test_bit(HCI_CONN_FLUSH_KEY, 1048 &hcon->flags); 1049 } else { 1050 /* The LTKs, IRKs and CSRKs should be persistent only if 1051 * both sides had the bonding bit set in their 1052 * authentication requests. 1053 */ 1054 persistent = !!((req->auth_req & rsp->auth_req) & 1055 SMP_AUTH_BONDING); 1056 } 1057 1058 if (smp->remote_irk) { 1059 mgmt_new_irk(hdev, smp->remote_irk, persistent); 1060 1061 /* Now that user space can be considered to know the 1062 * identity address track the connection based on it 1063 * from now on (assuming this is an LE link). 1064 */ 1065 if (hcon->type == LE_LINK) { 1066 bacpy(&hcon->dst, &smp->remote_irk->bdaddr); 1067 hcon->dst_type = smp->remote_irk->addr_type; 1068 queue_work(hdev->workqueue, &conn->id_addr_update_work); 1069 } 1070 } 1071 1072 if (smp->csrk) { 1073 smp->csrk->bdaddr_type = hcon->dst_type; 1074 bacpy(&smp->csrk->bdaddr, &hcon->dst); 1075 mgmt_new_csrk(hdev, smp->csrk, persistent); 1076 } 1077 1078 if (smp->slave_csrk) { 1079 smp->slave_csrk->bdaddr_type = hcon->dst_type; 1080 bacpy(&smp->slave_csrk->bdaddr, &hcon->dst); 1081 mgmt_new_csrk(hdev, smp->slave_csrk, persistent); 1082 } 1083 1084 if (smp->ltk) { 1085 smp->ltk->bdaddr_type = hcon->dst_type; 1086 bacpy(&smp->ltk->bdaddr, &hcon->dst); 1087 mgmt_new_ltk(hdev, smp->ltk, persistent); 1088 } 1089 1090 if (smp->slave_ltk) { 1091 smp->slave_ltk->bdaddr_type = hcon->dst_type; 1092 bacpy(&smp->slave_ltk->bdaddr, &hcon->dst); 1093 mgmt_new_ltk(hdev, smp->slave_ltk, persistent); 1094 } 1095 1096 if (smp->link_key) { 1097 struct link_key *key; 1098 u8 type; 1099 1100 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1101 type = HCI_LK_DEBUG_COMBINATION; 1102 else if (hcon->sec_level == BT_SECURITY_FIPS) 1103 type = HCI_LK_AUTH_COMBINATION_P256; 1104 else 1105 type = HCI_LK_UNAUTH_COMBINATION_P256; 1106 1107 key = hci_add_link_key(hdev, smp->conn->hcon, &hcon->dst, 1108 smp->link_key, type, 0, &persistent); 1109 if (key) { 1110 mgmt_new_link_key(hdev, key, persistent); 1111 1112 /* Don't keep debug keys around if the relevant 1113 * flag is not set. 1114 */ 1115 if (!hci_dev_test_flag(hdev, HCI_KEEP_DEBUG_KEYS) && 1116 key->type == HCI_LK_DEBUG_COMBINATION) { 1117 list_del_rcu(&key->list); 1118 kfree_rcu(key, rcu); 1119 } 1120 } 1121 } 1122 } 1123 1124 static void sc_add_ltk(struct smp_chan *smp) 1125 { 1126 struct hci_conn *hcon = smp->conn->hcon; 1127 u8 key_type, auth; 1128 1129 if (test_bit(SMP_FLAG_DEBUG_KEY, &smp->flags)) 1130 key_type = SMP_LTK_P256_DEBUG; 1131 else 1132 key_type = SMP_LTK_P256; 1133 1134 if (hcon->pending_sec_level == BT_SECURITY_FIPS) 1135 auth = 1; 1136 else 1137 auth = 0; 1138 1139 smp->ltk = hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 1140 key_type, auth, smp->tk, smp->enc_key_size, 1141 0, 0); 1142 } 1143 1144 static void sc_generate_link_key(struct smp_chan *smp) 1145 { 1146 /* From core spec. Spells out in ASCII as 'lebr'. */ 1147 const u8 lebr[4] = { 0x72, 0x62, 0x65, 0x6c }; 1148 1149 smp->link_key = kzalloc(16, GFP_KERNEL); 1150 if (!smp->link_key) 1151 return; 1152 1153 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1154 /* SALT = 0x000000000000000000000000746D7031 */ 1155 const u8 salt[16] = { 0x31, 0x70, 0x6d, 0x74 }; 1156 1157 if (smp_h7(smp->tfm_cmac, smp->tk, salt, smp->link_key)) { 1158 kfree_sensitive(smp->link_key); 1159 smp->link_key = NULL; 1160 return; 1161 } 1162 } else { 1163 /* From core spec. Spells out in ASCII as 'tmp1'. */ 1164 const u8 tmp1[4] = { 0x31, 0x70, 0x6d, 0x74 }; 1165 1166 if (smp_h6(smp->tfm_cmac, smp->tk, tmp1, smp->link_key)) { 1167 kfree_sensitive(smp->link_key); 1168 smp->link_key = NULL; 1169 return; 1170 } 1171 } 1172 1173 if (smp_h6(smp->tfm_cmac, smp->link_key, lebr, smp->link_key)) { 1174 kfree_sensitive(smp->link_key); 1175 smp->link_key = NULL; 1176 return; 1177 } 1178 } 1179 1180 static void smp_allow_key_dist(struct smp_chan *smp) 1181 { 1182 /* Allow the first expected phase 3 PDU. The rest of the PDUs 1183 * will be allowed in each PDU handler to ensure we receive 1184 * them in the correct order. 1185 */ 1186 if (smp->remote_key_dist & SMP_DIST_ENC_KEY) 1187 SMP_ALLOW_CMD(smp, SMP_CMD_ENCRYPT_INFO); 1188 else if (smp->remote_key_dist & SMP_DIST_ID_KEY) 1189 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 1190 else if (smp->remote_key_dist & SMP_DIST_SIGN) 1191 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 1192 } 1193 1194 static void sc_generate_ltk(struct smp_chan *smp) 1195 { 1196 /* From core spec. Spells out in ASCII as 'brle'. */ 1197 const u8 brle[4] = { 0x65, 0x6c, 0x72, 0x62 }; 1198 struct hci_conn *hcon = smp->conn->hcon; 1199 struct hci_dev *hdev = hcon->hdev; 1200 struct link_key *key; 1201 1202 key = hci_find_link_key(hdev, &hcon->dst); 1203 if (!key) { 1204 bt_dev_err(hdev, "no Link Key found to generate LTK"); 1205 return; 1206 } 1207 1208 if (key->type == HCI_LK_DEBUG_COMBINATION) 1209 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1210 1211 if (test_bit(SMP_FLAG_CT2, &smp->flags)) { 1212 /* SALT = 0x000000000000000000000000746D7032 */ 1213 const u8 salt[16] = { 0x32, 0x70, 0x6d, 0x74 }; 1214 1215 if (smp_h7(smp->tfm_cmac, key->val, salt, smp->tk)) 1216 return; 1217 } else { 1218 /* From core spec. Spells out in ASCII as 'tmp2'. */ 1219 const u8 tmp2[4] = { 0x32, 0x70, 0x6d, 0x74 }; 1220 1221 if (smp_h6(smp->tfm_cmac, key->val, tmp2, smp->tk)) 1222 return; 1223 } 1224 1225 if (smp_h6(smp->tfm_cmac, smp->tk, brle, smp->tk)) 1226 return; 1227 1228 sc_add_ltk(smp); 1229 } 1230 1231 static void smp_distribute_keys(struct smp_chan *smp) 1232 { 1233 struct smp_cmd_pairing *req, *rsp; 1234 struct l2cap_conn *conn = smp->conn; 1235 struct hci_conn *hcon = conn->hcon; 1236 struct hci_dev *hdev = hcon->hdev; 1237 __u8 *keydist; 1238 1239 BT_DBG("conn %p", conn); 1240 1241 rsp = (void *) &smp->prsp[1]; 1242 1243 /* The responder sends its keys first */ 1244 if (hcon->out && (smp->remote_key_dist & KEY_DIST_MASK)) { 1245 smp_allow_key_dist(smp); 1246 return; 1247 } 1248 1249 req = (void *) &smp->preq[1]; 1250 1251 if (hcon->out) { 1252 keydist = &rsp->init_key_dist; 1253 *keydist &= req->init_key_dist; 1254 } else { 1255 keydist = &rsp->resp_key_dist; 1256 *keydist &= req->resp_key_dist; 1257 } 1258 1259 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1260 if (hcon->type == LE_LINK && (*keydist & SMP_DIST_LINK_KEY)) 1261 sc_generate_link_key(smp); 1262 if (hcon->type == ACL_LINK && (*keydist & SMP_DIST_ENC_KEY)) 1263 sc_generate_ltk(smp); 1264 1265 /* Clear the keys which are generated but not distributed */ 1266 *keydist &= ~SMP_SC_NO_DIST; 1267 } 1268 1269 BT_DBG("keydist 0x%x", *keydist); 1270 1271 if (*keydist & SMP_DIST_ENC_KEY) { 1272 struct smp_cmd_encrypt_info enc; 1273 struct smp_cmd_master_ident ident; 1274 struct smp_ltk *ltk; 1275 u8 authenticated; 1276 __le16 ediv; 1277 __le64 rand; 1278 1279 /* Make sure we generate only the significant amount of 1280 * bytes based on the encryption key size, and set the rest 1281 * of the value to zeroes. 1282 */ 1283 get_random_bytes(enc.ltk, smp->enc_key_size); 1284 memset(enc.ltk + smp->enc_key_size, 0, 1285 sizeof(enc.ltk) - smp->enc_key_size); 1286 1287 get_random_bytes(&ediv, sizeof(ediv)); 1288 get_random_bytes(&rand, sizeof(rand)); 1289 1290 smp_send_cmd(conn, SMP_CMD_ENCRYPT_INFO, sizeof(enc), &enc); 1291 1292 authenticated = hcon->sec_level == BT_SECURITY_HIGH; 1293 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, 1294 SMP_LTK_SLAVE, authenticated, enc.ltk, 1295 smp->enc_key_size, ediv, rand); 1296 smp->slave_ltk = ltk; 1297 1298 ident.ediv = ediv; 1299 ident.rand = rand; 1300 1301 smp_send_cmd(conn, SMP_CMD_MASTER_IDENT, sizeof(ident), &ident); 1302 1303 *keydist &= ~SMP_DIST_ENC_KEY; 1304 } 1305 1306 if (*keydist & SMP_DIST_ID_KEY) { 1307 struct smp_cmd_ident_addr_info addrinfo; 1308 struct smp_cmd_ident_info idinfo; 1309 1310 memcpy(idinfo.irk, hdev->irk, sizeof(idinfo.irk)); 1311 1312 smp_send_cmd(conn, SMP_CMD_IDENT_INFO, sizeof(idinfo), &idinfo); 1313 1314 /* The hci_conn contains the local identity address 1315 * after the connection has been established. 1316 * 1317 * This is true even when the connection has been 1318 * established using a resolvable random address. 1319 */ 1320 bacpy(&addrinfo.bdaddr, &hcon->src); 1321 addrinfo.addr_type = hcon->src_type; 1322 1323 smp_send_cmd(conn, SMP_CMD_IDENT_ADDR_INFO, sizeof(addrinfo), 1324 &addrinfo); 1325 1326 *keydist &= ~SMP_DIST_ID_KEY; 1327 } 1328 1329 if (*keydist & SMP_DIST_SIGN) { 1330 struct smp_cmd_sign_info sign; 1331 struct smp_csrk *csrk; 1332 1333 /* Generate a new random key */ 1334 get_random_bytes(sign.csrk, sizeof(sign.csrk)); 1335 1336 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 1337 if (csrk) { 1338 if (hcon->sec_level > BT_SECURITY_MEDIUM) 1339 csrk->type = MGMT_CSRK_LOCAL_AUTHENTICATED; 1340 else 1341 csrk->type = MGMT_CSRK_LOCAL_UNAUTHENTICATED; 1342 memcpy(csrk->val, sign.csrk, sizeof(csrk->val)); 1343 } 1344 smp->slave_csrk = csrk; 1345 1346 smp_send_cmd(conn, SMP_CMD_SIGN_INFO, sizeof(sign), &sign); 1347 1348 *keydist &= ~SMP_DIST_SIGN; 1349 } 1350 1351 /* If there are still keys to be received wait for them */ 1352 if (smp->remote_key_dist & KEY_DIST_MASK) { 1353 smp_allow_key_dist(smp); 1354 return; 1355 } 1356 1357 set_bit(SMP_FLAG_COMPLETE, &smp->flags); 1358 smp_notify_keys(conn); 1359 1360 smp_chan_destroy(conn); 1361 } 1362 1363 static void smp_timeout(struct work_struct *work) 1364 { 1365 struct smp_chan *smp = container_of(work, struct smp_chan, 1366 security_timer.work); 1367 struct l2cap_conn *conn = smp->conn; 1368 1369 BT_DBG("conn %p", conn); 1370 1371 hci_disconnect(conn->hcon, HCI_ERROR_REMOTE_USER_TERM); 1372 } 1373 1374 static struct smp_chan *smp_chan_create(struct l2cap_conn *conn) 1375 { 1376 struct l2cap_chan *chan = conn->smp; 1377 struct smp_chan *smp; 1378 1379 smp = kzalloc(sizeof(*smp), GFP_ATOMIC); 1380 if (!smp) 1381 return NULL; 1382 1383 smp->tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 1384 if (IS_ERR(smp->tfm_cmac)) { 1385 BT_ERR("Unable to create CMAC crypto context"); 1386 goto zfree_smp; 1387 } 1388 1389 smp->tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 1390 if (IS_ERR(smp->tfm_ecdh)) { 1391 BT_ERR("Unable to create ECDH crypto context"); 1392 goto free_shash; 1393 } 1394 1395 smp->conn = conn; 1396 chan->data = smp; 1397 1398 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_FAIL); 1399 1400 INIT_DELAYED_WORK(&smp->security_timer, smp_timeout); 1401 1402 hci_conn_hold(conn->hcon); 1403 1404 return smp; 1405 1406 free_shash: 1407 crypto_free_shash(smp->tfm_cmac); 1408 zfree_smp: 1409 kfree_sensitive(smp); 1410 return NULL; 1411 } 1412 1413 static int sc_mackey_and_ltk(struct smp_chan *smp, u8 mackey[16], u8 ltk[16]) 1414 { 1415 struct hci_conn *hcon = smp->conn->hcon; 1416 u8 *na, *nb, a[7], b[7]; 1417 1418 if (hcon->out) { 1419 na = smp->prnd; 1420 nb = smp->rrnd; 1421 } else { 1422 na = smp->rrnd; 1423 nb = smp->prnd; 1424 } 1425 1426 memcpy(a, &hcon->init_addr, 6); 1427 memcpy(b, &hcon->resp_addr, 6); 1428 a[6] = hcon->init_addr_type; 1429 b[6] = hcon->resp_addr_type; 1430 1431 return smp_f5(smp->tfm_cmac, smp->dhkey, na, nb, a, b, mackey, ltk); 1432 } 1433 1434 static void sc_dhkey_check(struct smp_chan *smp) 1435 { 1436 struct hci_conn *hcon = smp->conn->hcon; 1437 struct smp_cmd_dhkey_check check; 1438 u8 a[7], b[7], *local_addr, *remote_addr; 1439 u8 io_cap[3], r[16]; 1440 1441 memcpy(a, &hcon->init_addr, 6); 1442 memcpy(b, &hcon->resp_addr, 6); 1443 a[6] = hcon->init_addr_type; 1444 b[6] = hcon->resp_addr_type; 1445 1446 if (hcon->out) { 1447 local_addr = a; 1448 remote_addr = b; 1449 memcpy(io_cap, &smp->preq[1], 3); 1450 } else { 1451 local_addr = b; 1452 remote_addr = a; 1453 memcpy(io_cap, &smp->prsp[1], 3); 1454 } 1455 1456 memset(r, 0, sizeof(r)); 1457 1458 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 1459 put_unaligned_le32(hcon->passkey_notify, r); 1460 1461 if (smp->method == REQ_OOB) 1462 memcpy(r, smp->rr, 16); 1463 1464 smp_f6(smp->tfm_cmac, smp->mackey, smp->prnd, smp->rrnd, r, io_cap, 1465 local_addr, remote_addr, check.e); 1466 1467 smp_send_cmd(smp->conn, SMP_CMD_DHKEY_CHECK, sizeof(check), &check); 1468 } 1469 1470 static u8 sc_passkey_send_confirm(struct smp_chan *smp) 1471 { 1472 struct l2cap_conn *conn = smp->conn; 1473 struct hci_conn *hcon = conn->hcon; 1474 struct smp_cmd_pairing_confirm cfm; 1475 u8 r; 1476 1477 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1478 r |= 0x80; 1479 1480 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1481 1482 if (smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, r, 1483 cfm.confirm_val)) 1484 return SMP_UNSPECIFIED; 1485 1486 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 1487 1488 return 0; 1489 } 1490 1491 static u8 sc_passkey_round(struct smp_chan *smp, u8 smp_op) 1492 { 1493 struct l2cap_conn *conn = smp->conn; 1494 struct hci_conn *hcon = conn->hcon; 1495 struct hci_dev *hdev = hcon->hdev; 1496 u8 cfm[16], r; 1497 1498 /* Ignore the PDU if we've already done 20 rounds (0 - 19) */ 1499 if (smp->passkey_round >= 20) 1500 return 0; 1501 1502 switch (smp_op) { 1503 case SMP_CMD_PAIRING_RANDOM: 1504 r = ((hcon->passkey_notify >> smp->passkey_round) & 0x01); 1505 r |= 0x80; 1506 1507 if (smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 1508 smp->rrnd, r, cfm)) 1509 return SMP_UNSPECIFIED; 1510 1511 if (crypto_memneq(smp->pcnf, cfm, 16)) 1512 return SMP_CONFIRM_FAILED; 1513 1514 smp->passkey_round++; 1515 1516 if (smp->passkey_round == 20) { 1517 /* Generate MacKey and LTK */ 1518 if (sc_mackey_and_ltk(smp, smp->mackey, smp->tk)) 1519 return SMP_UNSPECIFIED; 1520 } 1521 1522 /* The round is only complete when the initiator 1523 * receives pairing random. 1524 */ 1525 if (!hcon->out) { 1526 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1527 sizeof(smp->prnd), smp->prnd); 1528 if (smp->passkey_round == 20) 1529 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1530 else 1531 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1532 return 0; 1533 } 1534 1535 /* Start the next round */ 1536 if (smp->passkey_round != 20) 1537 return sc_passkey_round(smp, 0); 1538 1539 /* Passkey rounds are complete - start DHKey Check */ 1540 sc_dhkey_check(smp); 1541 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1542 1543 break; 1544 1545 case SMP_CMD_PAIRING_CONFIRM: 1546 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 1547 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 1548 return 0; 1549 } 1550 1551 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 1552 1553 if (hcon->out) { 1554 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 1555 sizeof(smp->prnd), smp->prnd); 1556 return 0; 1557 } 1558 1559 return sc_passkey_send_confirm(smp); 1560 1561 case SMP_CMD_PUBLIC_KEY: 1562 default: 1563 /* Initiating device starts the round */ 1564 if (!hcon->out) 1565 return 0; 1566 1567 BT_DBG("%s Starting passkey round %u", hdev->name, 1568 smp->passkey_round + 1); 1569 1570 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1571 1572 return sc_passkey_send_confirm(smp); 1573 } 1574 1575 return 0; 1576 } 1577 1578 static int sc_user_reply(struct smp_chan *smp, u16 mgmt_op, __le32 passkey) 1579 { 1580 struct l2cap_conn *conn = smp->conn; 1581 struct hci_conn *hcon = conn->hcon; 1582 u8 smp_op; 1583 1584 clear_bit(SMP_FLAG_WAIT_USER, &smp->flags); 1585 1586 switch (mgmt_op) { 1587 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1588 smp_failure(smp->conn, SMP_PASSKEY_ENTRY_FAILED); 1589 return 0; 1590 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1591 smp_failure(smp->conn, SMP_NUMERIC_COMP_FAILED); 1592 return 0; 1593 case MGMT_OP_USER_PASSKEY_REPLY: 1594 hcon->passkey_notify = le32_to_cpu(passkey); 1595 smp->passkey_round = 0; 1596 1597 if (test_and_clear_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) 1598 smp_op = SMP_CMD_PAIRING_CONFIRM; 1599 else 1600 smp_op = 0; 1601 1602 if (sc_passkey_round(smp, smp_op)) 1603 return -EIO; 1604 1605 return 0; 1606 } 1607 1608 /* Initiator sends DHKey check first */ 1609 if (hcon->out) { 1610 sc_dhkey_check(smp); 1611 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 1612 } else if (test_and_clear_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags)) { 1613 sc_dhkey_check(smp); 1614 sc_add_ltk(smp); 1615 } 1616 1617 return 0; 1618 } 1619 1620 int smp_user_confirm_reply(struct hci_conn *hcon, u16 mgmt_op, __le32 passkey) 1621 { 1622 struct l2cap_conn *conn = hcon->l2cap_data; 1623 struct l2cap_chan *chan; 1624 struct smp_chan *smp; 1625 u32 value; 1626 int err; 1627 1628 BT_DBG(""); 1629 1630 if (!conn) 1631 return -ENOTCONN; 1632 1633 chan = conn->smp; 1634 if (!chan) 1635 return -ENOTCONN; 1636 1637 l2cap_chan_lock(chan); 1638 if (!chan->data) { 1639 err = -ENOTCONN; 1640 goto unlock; 1641 } 1642 1643 smp = chan->data; 1644 1645 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1646 err = sc_user_reply(smp, mgmt_op, passkey); 1647 goto unlock; 1648 } 1649 1650 switch (mgmt_op) { 1651 case MGMT_OP_USER_PASSKEY_REPLY: 1652 value = le32_to_cpu(passkey); 1653 memset(smp->tk, 0, sizeof(smp->tk)); 1654 BT_DBG("PassKey: %d", value); 1655 put_unaligned_le32(value, smp->tk); 1656 fallthrough; 1657 case MGMT_OP_USER_CONFIRM_REPLY: 1658 set_bit(SMP_FLAG_TK_VALID, &smp->flags); 1659 break; 1660 case MGMT_OP_USER_PASSKEY_NEG_REPLY: 1661 case MGMT_OP_USER_CONFIRM_NEG_REPLY: 1662 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1663 err = 0; 1664 goto unlock; 1665 default: 1666 smp_failure(conn, SMP_PASSKEY_ENTRY_FAILED); 1667 err = -EOPNOTSUPP; 1668 goto unlock; 1669 } 1670 1671 err = 0; 1672 1673 /* If it is our turn to send Pairing Confirm, do so now */ 1674 if (test_bit(SMP_FLAG_CFM_PENDING, &smp->flags)) { 1675 u8 rsp = smp_confirm(smp); 1676 if (rsp) 1677 smp_failure(conn, rsp); 1678 } 1679 1680 unlock: 1681 l2cap_chan_unlock(chan); 1682 return err; 1683 } 1684 1685 static void build_bredr_pairing_cmd(struct smp_chan *smp, 1686 struct smp_cmd_pairing *req, 1687 struct smp_cmd_pairing *rsp) 1688 { 1689 struct l2cap_conn *conn = smp->conn; 1690 struct hci_dev *hdev = conn->hcon->hdev; 1691 u8 local_dist = 0, remote_dist = 0; 1692 1693 if (hci_dev_test_flag(hdev, HCI_BONDABLE)) { 1694 local_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1695 remote_dist = SMP_DIST_ENC_KEY | SMP_DIST_SIGN; 1696 } 1697 1698 if (hci_dev_test_flag(hdev, HCI_RPA_RESOLVING)) 1699 remote_dist |= SMP_DIST_ID_KEY; 1700 1701 if (hci_dev_test_flag(hdev, HCI_PRIVACY)) 1702 local_dist |= SMP_DIST_ID_KEY; 1703 1704 if (!rsp) { 1705 memset(req, 0, sizeof(*req)); 1706 1707 req->auth_req = SMP_AUTH_CT2; 1708 req->init_key_dist = local_dist; 1709 req->resp_key_dist = remote_dist; 1710 req->max_key_size = conn->hcon->enc_key_size; 1711 1712 smp->remote_key_dist = remote_dist; 1713 1714 return; 1715 } 1716 1717 memset(rsp, 0, sizeof(*rsp)); 1718 1719 rsp->auth_req = SMP_AUTH_CT2; 1720 rsp->max_key_size = conn->hcon->enc_key_size; 1721 rsp->init_key_dist = req->init_key_dist & remote_dist; 1722 rsp->resp_key_dist = req->resp_key_dist & local_dist; 1723 1724 smp->remote_key_dist = rsp->init_key_dist; 1725 } 1726 1727 static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) 1728 { 1729 struct smp_cmd_pairing rsp, *req = (void *) skb->data; 1730 struct l2cap_chan *chan = conn->smp; 1731 struct hci_dev *hdev = conn->hcon->hdev; 1732 struct smp_chan *smp; 1733 u8 key_size, auth, sec_level; 1734 int ret; 1735 1736 BT_DBG("conn %p", conn); 1737 1738 if (skb->len < sizeof(*req)) 1739 return SMP_INVALID_PARAMS; 1740 1741 if (conn->hcon->role != HCI_ROLE_SLAVE) 1742 return SMP_CMD_NOTSUPP; 1743 1744 if (!chan->data) 1745 smp = smp_chan_create(conn); 1746 else 1747 smp = chan->data; 1748 1749 if (!smp) 1750 return SMP_UNSPECIFIED; 1751 1752 /* We didn't start the pairing, so match remote */ 1753 auth = req->auth_req & AUTH_REQ_MASK(hdev); 1754 1755 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 1756 (auth & SMP_AUTH_BONDING)) 1757 return SMP_PAIRING_NOTSUPP; 1758 1759 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1760 return SMP_AUTH_REQUIREMENTS; 1761 1762 smp->preq[0] = SMP_CMD_PAIRING_REQ; 1763 memcpy(&smp->preq[1], req, sizeof(*req)); 1764 skb_pull(skb, sizeof(*req)); 1765 1766 /* If the remote side's OOB flag is set it means it has 1767 * successfully received our local OOB data - therefore set the 1768 * flag to indicate that local OOB is in use. 1769 */ 1770 if (req->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1771 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1772 1773 /* SMP over BR/EDR requires special treatment */ 1774 if (conn->hcon->type == ACL_LINK) { 1775 /* We must have a BR/EDR SC link */ 1776 if (!test_bit(HCI_CONN_AES_CCM, &conn->hcon->flags) && 1777 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 1778 return SMP_CROSS_TRANSP_NOT_ALLOWED; 1779 1780 set_bit(SMP_FLAG_SC, &smp->flags); 1781 1782 build_bredr_pairing_cmd(smp, req, &rsp); 1783 1784 if (req->auth_req & SMP_AUTH_CT2) 1785 set_bit(SMP_FLAG_CT2, &smp->flags); 1786 1787 key_size = min(req->max_key_size, rsp.max_key_size); 1788 if (check_enc_key_size(conn, key_size)) 1789 return SMP_ENC_KEY_SIZE; 1790 1791 /* Clear bits which are generated but not distributed */ 1792 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1793 1794 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1795 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1796 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1797 1798 smp_distribute_keys(smp); 1799 return 0; 1800 } 1801 1802 build_pairing_cmd(conn, req, &rsp, auth); 1803 1804 if (rsp.auth_req & SMP_AUTH_SC) { 1805 set_bit(SMP_FLAG_SC, &smp->flags); 1806 1807 if (rsp.auth_req & SMP_AUTH_CT2) 1808 set_bit(SMP_FLAG_CT2, &smp->flags); 1809 } 1810 1811 if (conn->hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 1812 sec_level = BT_SECURITY_MEDIUM; 1813 else 1814 sec_level = authreq_to_seclevel(auth); 1815 1816 if (sec_level > conn->hcon->pending_sec_level) 1817 conn->hcon->pending_sec_level = sec_level; 1818 1819 /* If we need MITM check that it can be achieved */ 1820 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1821 u8 method; 1822 1823 method = get_auth_method(smp, conn->hcon->io_capability, 1824 req->io_capability); 1825 if (method == JUST_WORKS || method == JUST_CFM) 1826 return SMP_AUTH_REQUIREMENTS; 1827 } 1828 1829 key_size = min(req->max_key_size, rsp.max_key_size); 1830 if (check_enc_key_size(conn, key_size)) 1831 return SMP_ENC_KEY_SIZE; 1832 1833 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1834 1835 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1836 memcpy(&smp->prsp[1], &rsp, sizeof(rsp)); 1837 1838 smp_send_cmd(conn, SMP_CMD_PAIRING_RSP, sizeof(rsp), &rsp); 1839 1840 clear_bit(SMP_FLAG_INITIATOR, &smp->flags); 1841 1842 /* Strictly speaking we shouldn't allow Pairing Confirm for the 1843 * SC case, however some implementations incorrectly copy RFU auth 1844 * req bits from our security request, which may create a false 1845 * positive SC enablement. 1846 */ 1847 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 1848 1849 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1850 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 1851 /* Clear bits which are generated but not distributed */ 1852 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1853 /* Wait for Public Key from Initiating Device */ 1854 return 0; 1855 } 1856 1857 /* Request setup of TK */ 1858 ret = tk_request(conn, 0, auth, rsp.io_capability, req->io_capability); 1859 if (ret) 1860 return SMP_UNSPECIFIED; 1861 1862 return 0; 1863 } 1864 1865 static u8 sc_send_public_key(struct smp_chan *smp) 1866 { 1867 struct hci_dev *hdev = smp->conn->hcon->hdev; 1868 1869 bt_dev_dbg(hdev, ""); 1870 1871 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 1872 struct l2cap_chan *chan = hdev->smp_data; 1873 struct smp_dev *smp_dev; 1874 1875 if (!chan || !chan->data) 1876 return SMP_UNSPECIFIED; 1877 1878 smp_dev = chan->data; 1879 1880 memcpy(smp->local_pk, smp_dev->local_pk, 64); 1881 memcpy(smp->lr, smp_dev->local_rand, 16); 1882 1883 if (smp_dev->debug_key) 1884 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1885 1886 goto done; 1887 } 1888 1889 if (hci_dev_test_flag(hdev, HCI_USE_DEBUG_KEYS)) { 1890 BT_DBG("Using debug keys"); 1891 if (set_ecdh_privkey(smp->tfm_ecdh, debug_sk)) 1892 return SMP_UNSPECIFIED; 1893 memcpy(smp->local_pk, debug_pk, 64); 1894 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 1895 } else { 1896 while (true) { 1897 /* Generate key pair for Secure Connections */ 1898 if (generate_ecdh_keys(smp->tfm_ecdh, smp->local_pk)) 1899 return SMP_UNSPECIFIED; 1900 1901 /* This is unlikely, but we need to check that 1902 * we didn't accidentially generate a debug key. 1903 */ 1904 if (crypto_memneq(smp->local_pk, debug_pk, 64)) 1905 break; 1906 } 1907 } 1908 1909 done: 1910 SMP_DBG("Local Public Key X: %32phN", smp->local_pk); 1911 SMP_DBG("Local Public Key Y: %32phN", smp->local_pk + 32); 1912 1913 smp_send_cmd(smp->conn, SMP_CMD_PUBLIC_KEY, 64, smp->local_pk); 1914 1915 return 0; 1916 } 1917 1918 static u8 smp_cmd_pairing_rsp(struct l2cap_conn *conn, struct sk_buff *skb) 1919 { 1920 struct smp_cmd_pairing *req, *rsp = (void *) skb->data; 1921 struct l2cap_chan *chan = conn->smp; 1922 struct smp_chan *smp = chan->data; 1923 struct hci_dev *hdev = conn->hcon->hdev; 1924 u8 key_size, auth; 1925 int ret; 1926 1927 BT_DBG("conn %p", conn); 1928 1929 if (skb->len < sizeof(*rsp)) 1930 return SMP_INVALID_PARAMS; 1931 1932 if (conn->hcon->role != HCI_ROLE_MASTER) 1933 return SMP_CMD_NOTSUPP; 1934 1935 skb_pull(skb, sizeof(*rsp)); 1936 1937 req = (void *) &smp->preq[1]; 1938 1939 key_size = min(req->max_key_size, rsp->max_key_size); 1940 if (check_enc_key_size(conn, key_size)) 1941 return SMP_ENC_KEY_SIZE; 1942 1943 auth = rsp->auth_req & AUTH_REQ_MASK(hdev); 1944 1945 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 1946 return SMP_AUTH_REQUIREMENTS; 1947 1948 /* If the remote side's OOB flag is set it means it has 1949 * successfully received our local OOB data - therefore set the 1950 * flag to indicate that local OOB is in use. 1951 */ 1952 if (rsp->oob_flag == SMP_OOB_PRESENT && SMP_DEV(hdev)->local_oob) 1953 set_bit(SMP_FLAG_LOCAL_OOB, &smp->flags); 1954 1955 smp->prsp[0] = SMP_CMD_PAIRING_RSP; 1956 memcpy(&smp->prsp[1], rsp, sizeof(*rsp)); 1957 1958 /* Update remote key distribution in case the remote cleared 1959 * some bits that we had enabled in our request. 1960 */ 1961 smp->remote_key_dist &= rsp->resp_key_dist; 1962 1963 if ((req->auth_req & SMP_AUTH_CT2) && (auth & SMP_AUTH_CT2)) 1964 set_bit(SMP_FLAG_CT2, &smp->flags); 1965 1966 /* For BR/EDR this means we're done and can start phase 3 */ 1967 if (conn->hcon->type == ACL_LINK) { 1968 /* Clear bits which are generated but not distributed */ 1969 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1970 smp_distribute_keys(smp); 1971 return 0; 1972 } 1973 1974 if ((req->auth_req & SMP_AUTH_SC) && (auth & SMP_AUTH_SC)) 1975 set_bit(SMP_FLAG_SC, &smp->flags); 1976 else if (conn->hcon->pending_sec_level > BT_SECURITY_HIGH) 1977 conn->hcon->pending_sec_level = BT_SECURITY_HIGH; 1978 1979 /* If we need MITM check that it can be achieved */ 1980 if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { 1981 u8 method; 1982 1983 method = get_auth_method(smp, req->io_capability, 1984 rsp->io_capability); 1985 if (method == JUST_WORKS || method == JUST_CFM) 1986 return SMP_AUTH_REQUIREMENTS; 1987 } 1988 1989 get_random_bytes(smp->prnd, sizeof(smp->prnd)); 1990 1991 /* Update remote key distribution in case the remote cleared 1992 * some bits that we had enabled in our request. 1993 */ 1994 smp->remote_key_dist &= rsp->resp_key_dist; 1995 1996 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 1997 /* Clear bits which are generated but not distributed */ 1998 smp->remote_key_dist &= ~SMP_SC_NO_DIST; 1999 SMP_ALLOW_CMD(smp, SMP_CMD_PUBLIC_KEY); 2000 return sc_send_public_key(smp); 2001 } 2002 2003 auth |= req->auth_req; 2004 2005 ret = tk_request(conn, 0, auth, req->io_capability, rsp->io_capability); 2006 if (ret) 2007 return SMP_UNSPECIFIED; 2008 2009 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2010 2011 /* Can't compose response until we have been confirmed */ 2012 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2013 return smp_confirm(smp); 2014 2015 return 0; 2016 } 2017 2018 static u8 sc_check_confirm(struct smp_chan *smp) 2019 { 2020 struct l2cap_conn *conn = smp->conn; 2021 2022 BT_DBG(""); 2023 2024 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2025 return sc_passkey_round(smp, SMP_CMD_PAIRING_CONFIRM); 2026 2027 if (conn->hcon->out) { 2028 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2029 smp->prnd); 2030 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2031 } 2032 2033 return 0; 2034 } 2035 2036 /* Work-around for some implementations that incorrectly copy RFU bits 2037 * from our security request and thereby create the impression that 2038 * we're doing SC when in fact the remote doesn't support it. 2039 */ 2040 static int fixup_sc_false_positive(struct smp_chan *smp) 2041 { 2042 struct l2cap_conn *conn = smp->conn; 2043 struct hci_conn *hcon = conn->hcon; 2044 struct hci_dev *hdev = hcon->hdev; 2045 struct smp_cmd_pairing *req, *rsp; 2046 u8 auth; 2047 2048 /* The issue is only observed when we're in slave role */ 2049 if (hcon->out) 2050 return SMP_UNSPECIFIED; 2051 2052 if (hci_dev_test_flag(hdev, HCI_SC_ONLY)) { 2053 bt_dev_err(hdev, "refusing legacy fallback in SC-only mode"); 2054 return SMP_UNSPECIFIED; 2055 } 2056 2057 bt_dev_err(hdev, "trying to fall back to legacy SMP"); 2058 2059 req = (void *) &smp->preq[1]; 2060 rsp = (void *) &smp->prsp[1]; 2061 2062 /* Rebuild key dist flags which may have been cleared for SC */ 2063 smp->remote_key_dist = (req->init_key_dist & rsp->resp_key_dist); 2064 2065 auth = req->auth_req & AUTH_REQ_MASK(hdev); 2066 2067 if (tk_request(conn, 0, auth, rsp->io_capability, req->io_capability)) { 2068 bt_dev_err(hdev, "failed to fall back to legacy SMP"); 2069 return SMP_UNSPECIFIED; 2070 } 2071 2072 clear_bit(SMP_FLAG_SC, &smp->flags); 2073 2074 return 0; 2075 } 2076 2077 static u8 smp_cmd_pairing_confirm(struct l2cap_conn *conn, struct sk_buff *skb) 2078 { 2079 struct l2cap_chan *chan = conn->smp; 2080 struct smp_chan *smp = chan->data; 2081 2082 BT_DBG("conn %p %s", conn, conn->hcon->out ? "master" : "slave"); 2083 2084 if (skb->len < sizeof(smp->pcnf)) 2085 return SMP_INVALID_PARAMS; 2086 2087 memcpy(smp->pcnf, skb->data, sizeof(smp->pcnf)); 2088 skb_pull(skb, sizeof(smp->pcnf)); 2089 2090 if (test_bit(SMP_FLAG_SC, &smp->flags)) { 2091 int ret; 2092 2093 /* Public Key exchange must happen before any other steps */ 2094 if (test_bit(SMP_FLAG_REMOTE_PK, &smp->flags)) 2095 return sc_check_confirm(smp); 2096 2097 BT_ERR("Unexpected SMP Pairing Confirm"); 2098 2099 ret = fixup_sc_false_positive(smp); 2100 if (ret) 2101 return ret; 2102 } 2103 2104 if (conn->hcon->out) { 2105 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2106 smp->prnd); 2107 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2108 return 0; 2109 } 2110 2111 if (test_bit(SMP_FLAG_TK_VALID, &smp->flags)) 2112 return smp_confirm(smp); 2113 2114 set_bit(SMP_FLAG_CFM_PENDING, &smp->flags); 2115 2116 return 0; 2117 } 2118 2119 static u8 smp_cmd_pairing_random(struct l2cap_conn *conn, struct sk_buff *skb) 2120 { 2121 struct l2cap_chan *chan = conn->smp; 2122 struct smp_chan *smp = chan->data; 2123 struct hci_conn *hcon = conn->hcon; 2124 u8 *pkax, *pkbx, *na, *nb, confirm_hint; 2125 u32 passkey; 2126 int err; 2127 2128 BT_DBG("conn %p", conn); 2129 2130 if (skb->len < sizeof(smp->rrnd)) 2131 return SMP_INVALID_PARAMS; 2132 2133 memcpy(smp->rrnd, skb->data, sizeof(smp->rrnd)); 2134 skb_pull(skb, sizeof(smp->rrnd)); 2135 2136 if (!test_bit(SMP_FLAG_SC, &smp->flags)) 2137 return smp_random(smp); 2138 2139 if (hcon->out) { 2140 pkax = smp->local_pk; 2141 pkbx = smp->remote_pk; 2142 na = smp->prnd; 2143 nb = smp->rrnd; 2144 } else { 2145 pkax = smp->remote_pk; 2146 pkbx = smp->local_pk; 2147 na = smp->rrnd; 2148 nb = smp->prnd; 2149 } 2150 2151 if (smp->method == REQ_OOB) { 2152 if (!hcon->out) 2153 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2154 sizeof(smp->prnd), smp->prnd); 2155 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2156 goto mackey_and_ltk; 2157 } 2158 2159 /* Passkey entry has special treatment */ 2160 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2161 return sc_passkey_round(smp, SMP_CMD_PAIRING_RANDOM); 2162 2163 if (hcon->out) { 2164 u8 cfm[16]; 2165 2166 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->local_pk, 2167 smp->rrnd, 0, cfm); 2168 if (err) 2169 return SMP_UNSPECIFIED; 2170 2171 if (crypto_memneq(smp->pcnf, cfm, 16)) 2172 return SMP_CONFIRM_FAILED; 2173 } else { 2174 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, sizeof(smp->prnd), 2175 smp->prnd); 2176 SMP_ALLOW_CMD(smp, SMP_CMD_DHKEY_CHECK); 2177 2178 /* Only Just-Works pairing requires extra checks */ 2179 if (smp->method != JUST_WORKS) 2180 goto mackey_and_ltk; 2181 2182 /* If there already exists long term key in local host, leave 2183 * the decision to user space since the remote device could 2184 * be legitimate or malicious. 2185 */ 2186 if (hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, 2187 hcon->role)) { 2188 /* Set passkey to 0. The value can be any number since 2189 * it'll be ignored anyway. 2190 */ 2191 passkey = 0; 2192 confirm_hint = 1; 2193 goto confirm; 2194 } 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 == 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 confirm_hint = 0; 2216 2217 confirm: 2218 if (smp->method == JUST_WORKS) 2219 confirm_hint = 1; 2220 2221 err = mgmt_user_confirm_request(hcon->hdev, &hcon->dst, hcon->type, 2222 hcon->dst_type, passkey, confirm_hint); 2223 if (err) 2224 return SMP_UNSPECIFIED; 2225 2226 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2227 2228 return 0; 2229 } 2230 2231 static bool smp_ltk_encrypt(struct l2cap_conn *conn, u8 sec_level) 2232 { 2233 struct smp_ltk *key; 2234 struct hci_conn *hcon = conn->hcon; 2235 2236 key = hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role); 2237 if (!key) 2238 return false; 2239 2240 if (smp_ltk_sec_level(key) < sec_level) 2241 return false; 2242 2243 if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &hcon->flags)) 2244 return true; 2245 2246 hci_le_start_enc(hcon, key->ediv, key->rand, key->val, key->enc_size); 2247 hcon->enc_key_size = key->enc_size; 2248 2249 /* We never store STKs for master role, so clear this flag */ 2250 clear_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags); 2251 2252 return true; 2253 } 2254 2255 bool smp_sufficient_security(struct hci_conn *hcon, u8 sec_level, 2256 enum smp_key_pref key_pref) 2257 { 2258 if (sec_level == BT_SECURITY_LOW) 2259 return true; 2260 2261 /* If we're encrypted with an STK but the caller prefers using 2262 * LTK claim insufficient security. This way we allow the 2263 * connection to be re-encrypted with an LTK, even if the LTK 2264 * provides the same level of security. Only exception is if we 2265 * don't have an LTK (e.g. because of key distribution bits). 2266 */ 2267 if (key_pref == SMP_USE_LTK && 2268 test_bit(HCI_CONN_STK_ENCRYPT, &hcon->flags) && 2269 hci_find_ltk(hcon->hdev, &hcon->dst, hcon->dst_type, hcon->role)) 2270 return false; 2271 2272 if (hcon->sec_level >= sec_level) 2273 return true; 2274 2275 return false; 2276 } 2277 2278 static u8 smp_cmd_security_req(struct l2cap_conn *conn, struct sk_buff *skb) 2279 { 2280 struct smp_cmd_security_req *rp = (void *) skb->data; 2281 struct smp_cmd_pairing cp; 2282 struct hci_conn *hcon = conn->hcon; 2283 struct hci_dev *hdev = hcon->hdev; 2284 struct smp_chan *smp; 2285 u8 sec_level, auth; 2286 2287 BT_DBG("conn %p", conn); 2288 2289 if (skb->len < sizeof(*rp)) 2290 return SMP_INVALID_PARAMS; 2291 2292 if (hcon->role != HCI_ROLE_MASTER) 2293 return SMP_CMD_NOTSUPP; 2294 2295 auth = rp->auth_req & AUTH_REQ_MASK(hdev); 2296 2297 if (hci_dev_test_flag(hdev, HCI_SC_ONLY) && !(auth & SMP_AUTH_SC)) 2298 return SMP_AUTH_REQUIREMENTS; 2299 2300 if (hcon->io_capability == HCI_IO_NO_INPUT_OUTPUT) 2301 sec_level = BT_SECURITY_MEDIUM; 2302 else 2303 sec_level = authreq_to_seclevel(auth); 2304 2305 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) { 2306 /* If link is already encrypted with sufficient security we 2307 * still need refresh encryption as per Core Spec 5.0 Vol 3, 2308 * Part H 2.4.6 2309 */ 2310 smp_ltk_encrypt(conn, hcon->sec_level); 2311 return 0; 2312 } 2313 2314 if (sec_level > hcon->pending_sec_level) 2315 hcon->pending_sec_level = sec_level; 2316 2317 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2318 return 0; 2319 2320 smp = smp_chan_create(conn); 2321 if (!smp) 2322 return SMP_UNSPECIFIED; 2323 2324 if (!hci_dev_test_flag(hdev, HCI_BONDABLE) && 2325 (auth & SMP_AUTH_BONDING)) 2326 return SMP_PAIRING_NOTSUPP; 2327 2328 skb_pull(skb, sizeof(*rp)); 2329 2330 memset(&cp, 0, sizeof(cp)); 2331 build_pairing_cmd(conn, &cp, NULL, auth); 2332 2333 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2334 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2335 2336 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2337 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2338 2339 return 0; 2340 } 2341 2342 int smp_conn_security(struct hci_conn *hcon, __u8 sec_level) 2343 { 2344 struct l2cap_conn *conn = hcon->l2cap_data; 2345 struct l2cap_chan *chan; 2346 struct smp_chan *smp; 2347 __u8 authreq; 2348 int ret; 2349 2350 BT_DBG("conn %p hcon %p level 0x%2.2x", conn, hcon, sec_level); 2351 2352 /* This may be NULL if there's an unexpected disconnection */ 2353 if (!conn) 2354 return 1; 2355 2356 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) 2357 return 1; 2358 2359 if (smp_sufficient_security(hcon, sec_level, SMP_USE_LTK)) 2360 return 1; 2361 2362 if (sec_level > hcon->pending_sec_level) 2363 hcon->pending_sec_level = sec_level; 2364 2365 if (hcon->role == HCI_ROLE_MASTER) 2366 if (smp_ltk_encrypt(conn, hcon->pending_sec_level)) 2367 return 0; 2368 2369 chan = conn->smp; 2370 if (!chan) { 2371 bt_dev_err(hcon->hdev, "security requested but not available"); 2372 return 1; 2373 } 2374 2375 l2cap_chan_lock(chan); 2376 2377 /* If SMP is already in progress ignore this request */ 2378 if (chan->data) { 2379 ret = 0; 2380 goto unlock; 2381 } 2382 2383 smp = smp_chan_create(conn); 2384 if (!smp) { 2385 ret = 1; 2386 goto unlock; 2387 } 2388 2389 authreq = seclevel_to_authreq(sec_level); 2390 2391 if (hci_dev_test_flag(hcon->hdev, HCI_SC_ENABLED)) { 2392 authreq |= SMP_AUTH_SC; 2393 if (hci_dev_test_flag(hcon->hdev, HCI_SSP_ENABLED)) 2394 authreq |= SMP_AUTH_CT2; 2395 } 2396 2397 /* Don't attempt to set MITM if setting is overridden by debugfs 2398 * Needed to pass certification test SM/MAS/PKE/BV-01-C 2399 */ 2400 if (!hci_dev_test_flag(hcon->hdev, HCI_FORCE_NO_MITM)) { 2401 /* Require MITM if IO Capability allows or the security level 2402 * requires it. 2403 */ 2404 if (hcon->io_capability != HCI_IO_NO_INPUT_OUTPUT || 2405 hcon->pending_sec_level > BT_SECURITY_MEDIUM) 2406 authreq |= SMP_AUTH_MITM; 2407 } 2408 2409 if (hcon->role == HCI_ROLE_MASTER) { 2410 struct smp_cmd_pairing cp; 2411 2412 build_pairing_cmd(conn, &cp, NULL, authreq); 2413 smp->preq[0] = SMP_CMD_PAIRING_REQ; 2414 memcpy(&smp->preq[1], &cp, sizeof(cp)); 2415 2416 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(cp), &cp); 2417 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 2418 } else { 2419 struct smp_cmd_security_req cp; 2420 cp.auth_req = authreq; 2421 smp_send_cmd(conn, SMP_CMD_SECURITY_REQ, sizeof(cp), &cp); 2422 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_REQ); 2423 } 2424 2425 set_bit(SMP_FLAG_INITIATOR, &smp->flags); 2426 ret = 0; 2427 2428 unlock: 2429 l2cap_chan_unlock(chan); 2430 return ret; 2431 } 2432 2433 int smp_cancel_and_remove_pairing(struct hci_dev *hdev, bdaddr_t *bdaddr, 2434 u8 addr_type) 2435 { 2436 struct hci_conn *hcon; 2437 struct l2cap_conn *conn; 2438 struct l2cap_chan *chan; 2439 struct smp_chan *smp; 2440 int err; 2441 2442 err = hci_remove_ltk(hdev, bdaddr, addr_type); 2443 hci_remove_irk(hdev, bdaddr, addr_type); 2444 2445 hcon = hci_conn_hash_lookup_le(hdev, bdaddr, addr_type); 2446 if (!hcon) 2447 goto done; 2448 2449 conn = hcon->l2cap_data; 2450 if (!conn) 2451 goto done; 2452 2453 chan = conn->smp; 2454 if (!chan) 2455 goto done; 2456 2457 l2cap_chan_lock(chan); 2458 2459 smp = chan->data; 2460 if (smp) { 2461 /* Set keys to NULL to make sure smp_failure() does not try to 2462 * remove and free already invalidated rcu list entries. */ 2463 smp->ltk = NULL; 2464 smp->slave_ltk = NULL; 2465 smp->remote_irk = NULL; 2466 2467 if (test_bit(SMP_FLAG_COMPLETE, &smp->flags)) 2468 smp_failure(conn, 0); 2469 else 2470 smp_failure(conn, SMP_UNSPECIFIED); 2471 err = 0; 2472 } 2473 2474 l2cap_chan_unlock(chan); 2475 2476 done: 2477 return err; 2478 } 2479 2480 static int smp_cmd_encrypt_info(struct l2cap_conn *conn, struct sk_buff *skb) 2481 { 2482 struct smp_cmd_encrypt_info *rp = (void *) skb->data; 2483 struct l2cap_chan *chan = conn->smp; 2484 struct smp_chan *smp = chan->data; 2485 2486 BT_DBG("conn %p", conn); 2487 2488 if (skb->len < sizeof(*rp)) 2489 return SMP_INVALID_PARAMS; 2490 2491 /* Pairing is aborted if any blocked keys are distributed */ 2492 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_LTK, 2493 rp->ltk)) { 2494 bt_dev_warn_ratelimited(conn->hcon->hdev, 2495 "LTK blocked for %pMR", 2496 &conn->hcon->dst); 2497 return SMP_INVALID_PARAMS; 2498 } 2499 2500 SMP_ALLOW_CMD(smp, SMP_CMD_MASTER_IDENT); 2501 2502 skb_pull(skb, sizeof(*rp)); 2503 2504 memcpy(smp->tk, rp->ltk, sizeof(smp->tk)); 2505 2506 return 0; 2507 } 2508 2509 static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb) 2510 { 2511 struct smp_cmd_master_ident *rp = (void *) skb->data; 2512 struct l2cap_chan *chan = conn->smp; 2513 struct smp_chan *smp = chan->data; 2514 struct hci_dev *hdev = conn->hcon->hdev; 2515 struct hci_conn *hcon = conn->hcon; 2516 struct smp_ltk *ltk; 2517 u8 authenticated; 2518 2519 BT_DBG("conn %p", conn); 2520 2521 if (skb->len < sizeof(*rp)) 2522 return SMP_INVALID_PARAMS; 2523 2524 /* Mark the information as received */ 2525 smp->remote_key_dist &= ~SMP_DIST_ENC_KEY; 2526 2527 if (smp->remote_key_dist & SMP_DIST_ID_KEY) 2528 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_INFO); 2529 else if (smp->remote_key_dist & SMP_DIST_SIGN) 2530 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2531 2532 skb_pull(skb, sizeof(*rp)); 2533 2534 authenticated = (hcon->sec_level == BT_SECURITY_HIGH); 2535 ltk = hci_add_ltk(hdev, &hcon->dst, hcon->dst_type, SMP_LTK, 2536 authenticated, smp->tk, smp->enc_key_size, 2537 rp->ediv, rp->rand); 2538 smp->ltk = ltk; 2539 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2540 smp_distribute_keys(smp); 2541 2542 return 0; 2543 } 2544 2545 static int smp_cmd_ident_info(struct l2cap_conn *conn, struct sk_buff *skb) 2546 { 2547 struct smp_cmd_ident_info *info = (void *) skb->data; 2548 struct l2cap_chan *chan = conn->smp; 2549 struct smp_chan *smp = chan->data; 2550 2551 BT_DBG(""); 2552 2553 if (skb->len < sizeof(*info)) 2554 return SMP_INVALID_PARAMS; 2555 2556 /* Pairing is aborted if any blocked keys are distributed */ 2557 if (hci_is_blocked_key(conn->hcon->hdev, HCI_BLOCKED_KEY_TYPE_IRK, 2558 info->irk)) { 2559 bt_dev_warn_ratelimited(conn->hcon->hdev, 2560 "Identity key blocked for %pMR", 2561 &conn->hcon->dst); 2562 return SMP_INVALID_PARAMS; 2563 } 2564 2565 SMP_ALLOW_CMD(smp, SMP_CMD_IDENT_ADDR_INFO); 2566 2567 skb_pull(skb, sizeof(*info)); 2568 2569 memcpy(smp->irk, info->irk, 16); 2570 2571 return 0; 2572 } 2573 2574 static int smp_cmd_ident_addr_info(struct l2cap_conn *conn, 2575 struct sk_buff *skb) 2576 { 2577 struct smp_cmd_ident_addr_info *info = (void *) skb->data; 2578 struct l2cap_chan *chan = conn->smp; 2579 struct smp_chan *smp = chan->data; 2580 struct hci_conn *hcon = conn->hcon; 2581 bdaddr_t rpa; 2582 2583 BT_DBG(""); 2584 2585 if (skb->len < sizeof(*info)) 2586 return SMP_INVALID_PARAMS; 2587 2588 /* Mark the information as received */ 2589 smp->remote_key_dist &= ~SMP_DIST_ID_KEY; 2590 2591 if (smp->remote_key_dist & SMP_DIST_SIGN) 2592 SMP_ALLOW_CMD(smp, SMP_CMD_SIGN_INFO); 2593 2594 skb_pull(skb, sizeof(*info)); 2595 2596 /* Strictly speaking the Core Specification (4.1) allows sending 2597 * an empty address which would force us to rely on just the IRK 2598 * as "identity information". However, since such 2599 * implementations are not known of and in order to not over 2600 * complicate our implementation, simply pretend that we never 2601 * received an IRK for such a device. 2602 * 2603 * The Identity Address must also be a Static Random or Public 2604 * Address, which hci_is_identity_address() checks for. 2605 */ 2606 if (!bacmp(&info->bdaddr, BDADDR_ANY) || 2607 !hci_is_identity_address(&info->bdaddr, info->addr_type)) { 2608 bt_dev_err(hcon->hdev, "ignoring IRK with no identity address"); 2609 goto distribute; 2610 } 2611 2612 /* Drop IRK if peer is using identity address during pairing but is 2613 * providing different address as identity information. 2614 * 2615 * Microsoft Surface Precision Mouse is known to have this bug. 2616 */ 2617 if (hci_is_identity_address(&hcon->dst, hcon->dst_type) && 2618 (bacmp(&info->bdaddr, &hcon->dst) || 2619 info->addr_type != hcon->dst_type)) { 2620 bt_dev_err(hcon->hdev, 2621 "ignoring IRK with invalid identity address"); 2622 goto distribute; 2623 } 2624 2625 bacpy(&smp->id_addr, &info->bdaddr); 2626 smp->id_addr_type = info->addr_type; 2627 2628 if (hci_bdaddr_is_rpa(&hcon->dst, hcon->dst_type)) 2629 bacpy(&rpa, &hcon->dst); 2630 else 2631 bacpy(&rpa, BDADDR_ANY); 2632 2633 smp->remote_irk = hci_add_irk(conn->hcon->hdev, &smp->id_addr, 2634 smp->id_addr_type, smp->irk, &rpa); 2635 2636 distribute: 2637 if (!(smp->remote_key_dist & KEY_DIST_MASK)) 2638 smp_distribute_keys(smp); 2639 2640 return 0; 2641 } 2642 2643 static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb) 2644 { 2645 struct smp_cmd_sign_info *rp = (void *) skb->data; 2646 struct l2cap_chan *chan = conn->smp; 2647 struct smp_chan *smp = chan->data; 2648 struct smp_csrk *csrk; 2649 2650 BT_DBG("conn %p", conn); 2651 2652 if (skb->len < sizeof(*rp)) 2653 return SMP_INVALID_PARAMS; 2654 2655 /* Mark the information as received */ 2656 smp->remote_key_dist &= ~SMP_DIST_SIGN; 2657 2658 skb_pull(skb, sizeof(*rp)); 2659 2660 csrk = kzalloc(sizeof(*csrk), GFP_KERNEL); 2661 if (csrk) { 2662 if (conn->hcon->sec_level > BT_SECURITY_MEDIUM) 2663 csrk->type = MGMT_CSRK_REMOTE_AUTHENTICATED; 2664 else 2665 csrk->type = MGMT_CSRK_REMOTE_UNAUTHENTICATED; 2666 memcpy(csrk->val, rp->csrk, sizeof(csrk->val)); 2667 } 2668 smp->csrk = csrk; 2669 smp_distribute_keys(smp); 2670 2671 return 0; 2672 } 2673 2674 static u8 sc_select_method(struct smp_chan *smp) 2675 { 2676 struct l2cap_conn *conn = smp->conn; 2677 struct hci_conn *hcon = conn->hcon; 2678 struct smp_cmd_pairing *local, *remote; 2679 u8 local_mitm, remote_mitm, local_io, remote_io, method; 2680 2681 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags) || 2682 test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) 2683 return REQ_OOB; 2684 2685 /* The preq/prsp contain the raw Pairing Request/Response PDUs 2686 * which are needed as inputs to some crypto functions. To get 2687 * the "struct smp_cmd_pairing" from them we need to skip the 2688 * first byte which contains the opcode. 2689 */ 2690 if (hcon->out) { 2691 local = (void *) &smp->preq[1]; 2692 remote = (void *) &smp->prsp[1]; 2693 } else { 2694 local = (void *) &smp->prsp[1]; 2695 remote = (void *) &smp->preq[1]; 2696 } 2697 2698 local_io = local->io_capability; 2699 remote_io = remote->io_capability; 2700 2701 local_mitm = (local->auth_req & SMP_AUTH_MITM); 2702 remote_mitm = (remote->auth_req & SMP_AUTH_MITM); 2703 2704 /* If either side wants MITM, look up the method from the table, 2705 * otherwise use JUST WORKS. 2706 */ 2707 if (local_mitm || remote_mitm) 2708 method = get_auth_method(smp, local_io, remote_io); 2709 else 2710 method = JUST_WORKS; 2711 2712 /* Don't confirm locally initiated pairing attempts */ 2713 if (method == JUST_CFM && test_bit(SMP_FLAG_INITIATOR, &smp->flags)) 2714 method = JUST_WORKS; 2715 2716 return method; 2717 } 2718 2719 static int smp_cmd_public_key(struct l2cap_conn *conn, struct sk_buff *skb) 2720 { 2721 struct smp_cmd_public_key *key = (void *) skb->data; 2722 struct hci_conn *hcon = conn->hcon; 2723 struct l2cap_chan *chan = conn->smp; 2724 struct smp_chan *smp = chan->data; 2725 struct hci_dev *hdev = hcon->hdev; 2726 struct crypto_kpp *tfm_ecdh; 2727 struct smp_cmd_pairing_confirm cfm; 2728 int err; 2729 2730 BT_DBG("conn %p", conn); 2731 2732 if (skb->len < sizeof(*key)) 2733 return SMP_INVALID_PARAMS; 2734 2735 memcpy(smp->remote_pk, key, 64); 2736 2737 if (test_bit(SMP_FLAG_REMOTE_OOB, &smp->flags)) { 2738 err = smp_f4(smp->tfm_cmac, smp->remote_pk, smp->remote_pk, 2739 smp->rr, 0, cfm.confirm_val); 2740 if (err) 2741 return SMP_UNSPECIFIED; 2742 2743 if (crypto_memneq(cfm.confirm_val, smp->pcnf, 16)) 2744 return SMP_CONFIRM_FAILED; 2745 } 2746 2747 /* Non-initiating device sends its public key after receiving 2748 * the key from the initiating device. 2749 */ 2750 if (!hcon->out) { 2751 err = sc_send_public_key(smp); 2752 if (err) 2753 return err; 2754 } 2755 2756 SMP_DBG("Remote Public Key X: %32phN", smp->remote_pk); 2757 SMP_DBG("Remote Public Key Y: %32phN", smp->remote_pk + 32); 2758 2759 /* Compute the shared secret on the same crypto tfm on which the private 2760 * key was set/generated. 2761 */ 2762 if (test_bit(SMP_FLAG_LOCAL_OOB, &smp->flags)) { 2763 struct l2cap_chan *hchan = hdev->smp_data; 2764 struct smp_dev *smp_dev; 2765 2766 if (!hchan || !hchan->data) 2767 return SMP_UNSPECIFIED; 2768 2769 smp_dev = hchan->data; 2770 2771 tfm_ecdh = smp_dev->tfm_ecdh; 2772 } else { 2773 tfm_ecdh = smp->tfm_ecdh; 2774 } 2775 2776 if (compute_ecdh_secret(tfm_ecdh, smp->remote_pk, smp->dhkey)) 2777 return SMP_UNSPECIFIED; 2778 2779 SMP_DBG("DHKey %32phN", smp->dhkey); 2780 2781 set_bit(SMP_FLAG_REMOTE_PK, &smp->flags); 2782 2783 smp->method = sc_select_method(smp); 2784 2785 BT_DBG("%s selected method 0x%02x", hdev->name, smp->method); 2786 2787 /* JUST_WORKS and JUST_CFM result in an unauthenticated key */ 2788 if (smp->method == JUST_WORKS || smp->method == JUST_CFM) 2789 hcon->pending_sec_level = BT_SECURITY_MEDIUM; 2790 else 2791 hcon->pending_sec_level = BT_SECURITY_FIPS; 2792 2793 if (!crypto_memneq(debug_pk, smp->remote_pk, 64)) 2794 set_bit(SMP_FLAG_DEBUG_KEY, &smp->flags); 2795 2796 if (smp->method == DSP_PASSKEY) { 2797 get_random_bytes(&hcon->passkey_notify, 2798 sizeof(hcon->passkey_notify)); 2799 hcon->passkey_notify %= 1000000; 2800 hcon->passkey_entered = 0; 2801 smp->passkey_round = 0; 2802 if (mgmt_user_passkey_notify(hdev, &hcon->dst, hcon->type, 2803 hcon->dst_type, 2804 hcon->passkey_notify, 2805 hcon->passkey_entered)) 2806 return SMP_UNSPECIFIED; 2807 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2808 return sc_passkey_round(smp, SMP_CMD_PUBLIC_KEY); 2809 } 2810 2811 if (smp->method == REQ_OOB) { 2812 if (hcon->out) 2813 smp_send_cmd(conn, SMP_CMD_PAIRING_RANDOM, 2814 sizeof(smp->prnd), smp->prnd); 2815 2816 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2817 2818 return 0; 2819 } 2820 2821 if (hcon->out) 2822 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2823 2824 if (smp->method == REQ_PASSKEY) { 2825 if (mgmt_user_passkey_request(hdev, &hcon->dst, hcon->type, 2826 hcon->dst_type)) 2827 return SMP_UNSPECIFIED; 2828 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_CONFIRM); 2829 set_bit(SMP_FLAG_WAIT_USER, &smp->flags); 2830 return 0; 2831 } 2832 2833 /* The Initiating device waits for the non-initiating device to 2834 * send the confirm value. 2835 */ 2836 if (conn->hcon->out) 2837 return 0; 2838 2839 err = smp_f4(smp->tfm_cmac, smp->local_pk, smp->remote_pk, smp->prnd, 2840 0, cfm.confirm_val); 2841 if (err) 2842 return SMP_UNSPECIFIED; 2843 2844 smp_send_cmd(conn, SMP_CMD_PAIRING_CONFIRM, sizeof(cfm), &cfm); 2845 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RANDOM); 2846 2847 return 0; 2848 } 2849 2850 static int smp_cmd_dhkey_check(struct l2cap_conn *conn, struct sk_buff *skb) 2851 { 2852 struct smp_cmd_dhkey_check *check = (void *) skb->data; 2853 struct l2cap_chan *chan = conn->smp; 2854 struct hci_conn *hcon = conn->hcon; 2855 struct smp_chan *smp = chan->data; 2856 u8 a[7], b[7], *local_addr, *remote_addr; 2857 u8 io_cap[3], r[16], e[16]; 2858 int err; 2859 2860 BT_DBG("conn %p", conn); 2861 2862 if (skb->len < sizeof(*check)) 2863 return SMP_INVALID_PARAMS; 2864 2865 memcpy(a, &hcon->init_addr, 6); 2866 memcpy(b, &hcon->resp_addr, 6); 2867 a[6] = hcon->init_addr_type; 2868 b[6] = hcon->resp_addr_type; 2869 2870 if (hcon->out) { 2871 local_addr = a; 2872 remote_addr = b; 2873 memcpy(io_cap, &smp->prsp[1], 3); 2874 } else { 2875 local_addr = b; 2876 remote_addr = a; 2877 memcpy(io_cap, &smp->preq[1], 3); 2878 } 2879 2880 memset(r, 0, sizeof(r)); 2881 2882 if (smp->method == REQ_PASSKEY || smp->method == DSP_PASSKEY) 2883 put_unaligned_le32(hcon->passkey_notify, r); 2884 else if (smp->method == REQ_OOB) 2885 memcpy(r, smp->lr, 16); 2886 2887 err = smp_f6(smp->tfm_cmac, smp->mackey, smp->rrnd, smp->prnd, r, 2888 io_cap, remote_addr, local_addr, e); 2889 if (err) 2890 return SMP_UNSPECIFIED; 2891 2892 if (crypto_memneq(check->e, e, 16)) 2893 return SMP_DHKEY_CHECK_FAILED; 2894 2895 if (!hcon->out) { 2896 if (test_bit(SMP_FLAG_WAIT_USER, &smp->flags)) { 2897 set_bit(SMP_FLAG_DHKEY_PENDING, &smp->flags); 2898 return 0; 2899 } 2900 2901 /* Slave sends DHKey check as response to master */ 2902 sc_dhkey_check(smp); 2903 } 2904 2905 sc_add_ltk(smp); 2906 2907 if (hcon->out) { 2908 hci_le_start_enc(hcon, 0, 0, smp->tk, smp->enc_key_size); 2909 hcon->enc_key_size = smp->enc_key_size; 2910 } 2911 2912 return 0; 2913 } 2914 2915 static int smp_cmd_keypress_notify(struct l2cap_conn *conn, 2916 struct sk_buff *skb) 2917 { 2918 struct smp_cmd_keypress_notify *kp = (void *) skb->data; 2919 2920 BT_DBG("value 0x%02x", kp->value); 2921 2922 return 0; 2923 } 2924 2925 static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb) 2926 { 2927 struct l2cap_conn *conn = chan->conn; 2928 struct hci_conn *hcon = conn->hcon; 2929 struct smp_chan *smp; 2930 __u8 code, reason; 2931 int err = 0; 2932 2933 if (skb->len < 1) 2934 return -EILSEQ; 2935 2936 if (!hci_dev_test_flag(hcon->hdev, HCI_LE_ENABLED)) { 2937 reason = SMP_PAIRING_NOTSUPP; 2938 goto done; 2939 } 2940 2941 code = skb->data[0]; 2942 skb_pull(skb, sizeof(code)); 2943 2944 smp = chan->data; 2945 2946 if (code > SMP_CMD_MAX) 2947 goto drop; 2948 2949 if (smp && !test_and_clear_bit(code, &smp->allow_cmd)) 2950 goto drop; 2951 2952 /* If we don't have a context the only allowed commands are 2953 * pairing request and security request. 2954 */ 2955 if (!smp && code != SMP_CMD_PAIRING_REQ && code != SMP_CMD_SECURITY_REQ) 2956 goto drop; 2957 2958 switch (code) { 2959 case SMP_CMD_PAIRING_REQ: 2960 reason = smp_cmd_pairing_req(conn, skb); 2961 break; 2962 2963 case SMP_CMD_PAIRING_FAIL: 2964 smp_failure(conn, 0); 2965 err = -EPERM; 2966 break; 2967 2968 case SMP_CMD_PAIRING_RSP: 2969 reason = smp_cmd_pairing_rsp(conn, skb); 2970 break; 2971 2972 case SMP_CMD_SECURITY_REQ: 2973 reason = smp_cmd_security_req(conn, skb); 2974 break; 2975 2976 case SMP_CMD_PAIRING_CONFIRM: 2977 reason = smp_cmd_pairing_confirm(conn, skb); 2978 break; 2979 2980 case SMP_CMD_PAIRING_RANDOM: 2981 reason = smp_cmd_pairing_random(conn, skb); 2982 break; 2983 2984 case SMP_CMD_ENCRYPT_INFO: 2985 reason = smp_cmd_encrypt_info(conn, skb); 2986 break; 2987 2988 case SMP_CMD_MASTER_IDENT: 2989 reason = smp_cmd_master_ident(conn, skb); 2990 break; 2991 2992 case SMP_CMD_IDENT_INFO: 2993 reason = smp_cmd_ident_info(conn, skb); 2994 break; 2995 2996 case SMP_CMD_IDENT_ADDR_INFO: 2997 reason = smp_cmd_ident_addr_info(conn, skb); 2998 break; 2999 3000 case SMP_CMD_SIGN_INFO: 3001 reason = smp_cmd_sign_info(conn, skb); 3002 break; 3003 3004 case SMP_CMD_PUBLIC_KEY: 3005 reason = smp_cmd_public_key(conn, skb); 3006 break; 3007 3008 case SMP_CMD_DHKEY_CHECK: 3009 reason = smp_cmd_dhkey_check(conn, skb); 3010 break; 3011 3012 case SMP_CMD_KEYPRESS_NOTIFY: 3013 reason = smp_cmd_keypress_notify(conn, skb); 3014 break; 3015 3016 default: 3017 BT_DBG("Unknown command code 0x%2.2x", code); 3018 reason = SMP_CMD_NOTSUPP; 3019 goto done; 3020 } 3021 3022 done: 3023 if (!err) { 3024 if (reason) 3025 smp_failure(conn, reason); 3026 kfree_skb(skb); 3027 } 3028 3029 return err; 3030 3031 drop: 3032 bt_dev_err(hcon->hdev, "unexpected SMP command 0x%02x from %pMR", 3033 code, &hcon->dst); 3034 kfree_skb(skb); 3035 return 0; 3036 } 3037 3038 static void smp_teardown_cb(struct l2cap_chan *chan, int err) 3039 { 3040 struct l2cap_conn *conn = chan->conn; 3041 3042 BT_DBG("chan %p", chan); 3043 3044 if (chan->data) 3045 smp_chan_destroy(conn); 3046 3047 conn->smp = NULL; 3048 l2cap_chan_put(chan); 3049 } 3050 3051 static void bredr_pairing(struct l2cap_chan *chan) 3052 { 3053 struct l2cap_conn *conn = chan->conn; 3054 struct hci_conn *hcon = conn->hcon; 3055 struct hci_dev *hdev = hcon->hdev; 3056 struct smp_cmd_pairing req; 3057 struct smp_chan *smp; 3058 3059 BT_DBG("chan %p", chan); 3060 3061 /* Only new pairings are interesting */ 3062 if (!test_bit(HCI_CONN_NEW_LINK_KEY, &hcon->flags)) 3063 return; 3064 3065 /* Don't bother if we're not encrypted */ 3066 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3067 return; 3068 3069 /* Only master may initiate SMP over BR/EDR */ 3070 if (hcon->role != HCI_ROLE_MASTER) 3071 return; 3072 3073 /* Secure Connections support must be enabled */ 3074 if (!hci_dev_test_flag(hdev, HCI_SC_ENABLED)) 3075 return; 3076 3077 /* BR/EDR must use Secure Connections for SMP */ 3078 if (!test_bit(HCI_CONN_AES_CCM, &hcon->flags) && 3079 !hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3080 return; 3081 3082 /* If our LE support is not enabled don't do anything */ 3083 if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) 3084 return; 3085 3086 /* Don't bother if remote LE support is not enabled */ 3087 if (!lmp_host_le_capable(hcon)) 3088 return; 3089 3090 /* Remote must support SMP fixed chan for BR/EDR */ 3091 if (!(conn->remote_fixed_chan & L2CAP_FC_SMP_BREDR)) 3092 return; 3093 3094 /* Don't bother if SMP is already ongoing */ 3095 if (chan->data) 3096 return; 3097 3098 smp = smp_chan_create(conn); 3099 if (!smp) { 3100 bt_dev_err(hdev, "unable to create SMP context for BR/EDR"); 3101 return; 3102 } 3103 3104 set_bit(SMP_FLAG_SC, &smp->flags); 3105 3106 BT_DBG("%s starting SMP over BR/EDR", hdev->name); 3107 3108 /* Prepare and send the BR/EDR SMP Pairing Request */ 3109 build_bredr_pairing_cmd(smp, &req, NULL); 3110 3111 smp->preq[0] = SMP_CMD_PAIRING_REQ; 3112 memcpy(&smp->preq[1], &req, sizeof(req)); 3113 3114 smp_send_cmd(conn, SMP_CMD_PAIRING_REQ, sizeof(req), &req); 3115 SMP_ALLOW_CMD(smp, SMP_CMD_PAIRING_RSP); 3116 } 3117 3118 static void smp_resume_cb(struct l2cap_chan *chan) 3119 { 3120 struct smp_chan *smp = chan->data; 3121 struct l2cap_conn *conn = chan->conn; 3122 struct hci_conn *hcon = conn->hcon; 3123 3124 BT_DBG("chan %p", chan); 3125 3126 if (hcon->type == ACL_LINK) { 3127 bredr_pairing(chan); 3128 return; 3129 } 3130 3131 if (!smp) 3132 return; 3133 3134 if (!test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3135 return; 3136 3137 cancel_delayed_work(&smp->security_timer); 3138 3139 smp_distribute_keys(smp); 3140 } 3141 3142 static void smp_ready_cb(struct l2cap_chan *chan) 3143 { 3144 struct l2cap_conn *conn = chan->conn; 3145 struct hci_conn *hcon = conn->hcon; 3146 3147 BT_DBG("chan %p", chan); 3148 3149 /* No need to call l2cap_chan_hold() here since we already own 3150 * the reference taken in smp_new_conn_cb(). This is just the 3151 * first time that we tie it to a specific pointer. The code in 3152 * l2cap_core.c ensures that there's no risk this function wont 3153 * get called if smp_new_conn_cb was previously called. 3154 */ 3155 conn->smp = chan; 3156 3157 if (hcon->type == ACL_LINK && test_bit(HCI_CONN_ENCRYPT, &hcon->flags)) 3158 bredr_pairing(chan); 3159 } 3160 3161 static int smp_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb) 3162 { 3163 int err; 3164 3165 BT_DBG("chan %p", chan); 3166 3167 err = smp_sig_channel(chan, skb); 3168 if (err) { 3169 struct smp_chan *smp = chan->data; 3170 3171 if (smp) 3172 cancel_delayed_work_sync(&smp->security_timer); 3173 3174 hci_disconnect(chan->conn->hcon, HCI_ERROR_AUTH_FAILURE); 3175 } 3176 3177 return err; 3178 } 3179 3180 static struct sk_buff *smp_alloc_skb_cb(struct l2cap_chan *chan, 3181 unsigned long hdr_len, 3182 unsigned long len, int nb) 3183 { 3184 struct sk_buff *skb; 3185 3186 skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL); 3187 if (!skb) 3188 return ERR_PTR(-ENOMEM); 3189 3190 skb->priority = HCI_PRIO_MAX; 3191 bt_cb(skb)->l2cap.chan = chan; 3192 3193 return skb; 3194 } 3195 3196 static const struct l2cap_ops smp_chan_ops = { 3197 .name = "Security Manager", 3198 .ready = smp_ready_cb, 3199 .recv = smp_recv_cb, 3200 .alloc_skb = smp_alloc_skb_cb, 3201 .teardown = smp_teardown_cb, 3202 .resume = smp_resume_cb, 3203 3204 .new_connection = l2cap_chan_no_new_connection, 3205 .state_change = l2cap_chan_no_state_change, 3206 .close = l2cap_chan_no_close, 3207 .defer = l2cap_chan_no_defer, 3208 .suspend = l2cap_chan_no_suspend, 3209 .set_shutdown = l2cap_chan_no_set_shutdown, 3210 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3211 }; 3212 3213 static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan) 3214 { 3215 struct l2cap_chan *chan; 3216 3217 BT_DBG("pchan %p", pchan); 3218 3219 chan = l2cap_chan_create(); 3220 if (!chan) 3221 return NULL; 3222 3223 chan->chan_type = pchan->chan_type; 3224 chan->ops = &smp_chan_ops; 3225 chan->scid = pchan->scid; 3226 chan->dcid = chan->scid; 3227 chan->imtu = pchan->imtu; 3228 chan->omtu = pchan->omtu; 3229 chan->mode = pchan->mode; 3230 3231 /* Other L2CAP channels may request SMP routines in order to 3232 * change the security level. This means that the SMP channel 3233 * lock must be considered in its own category to avoid lockdep 3234 * warnings. 3235 */ 3236 atomic_set(&chan->nesting, L2CAP_NESTING_SMP); 3237 3238 BT_DBG("created chan %p", chan); 3239 3240 return chan; 3241 } 3242 3243 static const struct l2cap_ops smp_root_chan_ops = { 3244 .name = "Security Manager Root", 3245 .new_connection = smp_new_conn_cb, 3246 3247 /* None of these are implemented for the root channel */ 3248 .close = l2cap_chan_no_close, 3249 .alloc_skb = l2cap_chan_no_alloc_skb, 3250 .recv = l2cap_chan_no_recv, 3251 .state_change = l2cap_chan_no_state_change, 3252 .teardown = l2cap_chan_no_teardown, 3253 .ready = l2cap_chan_no_ready, 3254 .defer = l2cap_chan_no_defer, 3255 .suspend = l2cap_chan_no_suspend, 3256 .resume = l2cap_chan_no_resume, 3257 .set_shutdown = l2cap_chan_no_set_shutdown, 3258 .get_sndtimeo = l2cap_chan_no_get_sndtimeo, 3259 }; 3260 3261 static struct l2cap_chan *smp_add_cid(struct hci_dev *hdev, u16 cid) 3262 { 3263 struct l2cap_chan *chan; 3264 struct smp_dev *smp; 3265 struct crypto_shash *tfm_cmac; 3266 struct crypto_kpp *tfm_ecdh; 3267 3268 if (cid == L2CAP_CID_SMP_BREDR) { 3269 smp = NULL; 3270 goto create_chan; 3271 } 3272 3273 smp = kzalloc(sizeof(*smp), GFP_KERNEL); 3274 if (!smp) 3275 return ERR_PTR(-ENOMEM); 3276 3277 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3278 if (IS_ERR(tfm_cmac)) { 3279 BT_ERR("Unable to create CMAC crypto context"); 3280 kfree_sensitive(smp); 3281 return ERR_CAST(tfm_cmac); 3282 } 3283 3284 tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 3285 if (IS_ERR(tfm_ecdh)) { 3286 BT_ERR("Unable to create ECDH crypto context"); 3287 crypto_free_shash(tfm_cmac); 3288 kfree_sensitive(smp); 3289 return ERR_CAST(tfm_ecdh); 3290 } 3291 3292 smp->local_oob = false; 3293 smp->tfm_cmac = tfm_cmac; 3294 smp->tfm_ecdh = tfm_ecdh; 3295 3296 create_chan: 3297 chan = l2cap_chan_create(); 3298 if (!chan) { 3299 if (smp) { 3300 crypto_free_shash(smp->tfm_cmac); 3301 crypto_free_kpp(smp->tfm_ecdh); 3302 kfree_sensitive(smp); 3303 } 3304 return ERR_PTR(-ENOMEM); 3305 } 3306 3307 chan->data = smp; 3308 3309 l2cap_add_scid(chan, cid); 3310 3311 l2cap_chan_set_defaults(chan); 3312 3313 if (cid == L2CAP_CID_SMP) { 3314 u8 bdaddr_type; 3315 3316 hci_copy_identity_address(hdev, &chan->src, &bdaddr_type); 3317 3318 if (bdaddr_type == ADDR_LE_DEV_PUBLIC) 3319 chan->src_type = BDADDR_LE_PUBLIC; 3320 else 3321 chan->src_type = BDADDR_LE_RANDOM; 3322 } else { 3323 bacpy(&chan->src, &hdev->bdaddr); 3324 chan->src_type = BDADDR_BREDR; 3325 } 3326 3327 chan->state = BT_LISTEN; 3328 chan->mode = L2CAP_MODE_BASIC; 3329 chan->imtu = L2CAP_DEFAULT_MTU; 3330 chan->ops = &smp_root_chan_ops; 3331 3332 /* Set correct nesting level for a parent/listening channel */ 3333 atomic_set(&chan->nesting, L2CAP_NESTING_PARENT); 3334 3335 return chan; 3336 } 3337 3338 static void smp_del_chan(struct l2cap_chan *chan) 3339 { 3340 struct smp_dev *smp; 3341 3342 BT_DBG("chan %p", chan); 3343 3344 smp = chan->data; 3345 if (smp) { 3346 chan->data = NULL; 3347 crypto_free_shash(smp->tfm_cmac); 3348 crypto_free_kpp(smp->tfm_ecdh); 3349 kfree_sensitive(smp); 3350 } 3351 3352 l2cap_chan_put(chan); 3353 } 3354 3355 int smp_force_bredr(struct hci_dev *hdev, bool enable) 3356 { 3357 if (enable == hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3358 return -EALREADY; 3359 3360 if (enable) { 3361 struct l2cap_chan *chan; 3362 3363 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3364 if (IS_ERR(chan)) 3365 return PTR_ERR(chan); 3366 3367 hdev->smp_bredr_data = chan; 3368 } else { 3369 struct l2cap_chan *chan; 3370 3371 chan = hdev->smp_bredr_data; 3372 hdev->smp_bredr_data = NULL; 3373 smp_del_chan(chan); 3374 } 3375 3376 hci_dev_change_flag(hdev, HCI_FORCE_BREDR_SMP); 3377 3378 return 0; 3379 } 3380 3381 int smp_register(struct hci_dev *hdev) 3382 { 3383 struct l2cap_chan *chan; 3384 3385 BT_DBG("%s", hdev->name); 3386 3387 /* If the controller does not support Low Energy operation, then 3388 * there is also no need to register any SMP channel. 3389 */ 3390 if (!lmp_le_capable(hdev)) 3391 return 0; 3392 3393 if (WARN_ON(hdev->smp_data)) { 3394 chan = hdev->smp_data; 3395 hdev->smp_data = NULL; 3396 smp_del_chan(chan); 3397 } 3398 3399 chan = smp_add_cid(hdev, L2CAP_CID_SMP); 3400 if (IS_ERR(chan)) 3401 return PTR_ERR(chan); 3402 3403 hdev->smp_data = chan; 3404 3405 if (!lmp_sc_capable(hdev)) { 3406 /* Flag can be already set here (due to power toggle) */ 3407 if (!hci_dev_test_flag(hdev, HCI_FORCE_BREDR_SMP)) 3408 return 0; 3409 } 3410 3411 if (WARN_ON(hdev->smp_bredr_data)) { 3412 chan = hdev->smp_bredr_data; 3413 hdev->smp_bredr_data = NULL; 3414 smp_del_chan(chan); 3415 } 3416 3417 chan = smp_add_cid(hdev, L2CAP_CID_SMP_BREDR); 3418 if (IS_ERR(chan)) { 3419 int err = PTR_ERR(chan); 3420 chan = hdev->smp_data; 3421 hdev->smp_data = NULL; 3422 smp_del_chan(chan); 3423 return err; 3424 } 3425 3426 hdev->smp_bredr_data = chan; 3427 3428 return 0; 3429 } 3430 3431 void smp_unregister(struct hci_dev *hdev) 3432 { 3433 struct l2cap_chan *chan; 3434 3435 if (hdev->smp_bredr_data) { 3436 chan = hdev->smp_bredr_data; 3437 hdev->smp_bredr_data = NULL; 3438 smp_del_chan(chan); 3439 } 3440 3441 if (hdev->smp_data) { 3442 chan = hdev->smp_data; 3443 hdev->smp_data = NULL; 3444 smp_del_chan(chan); 3445 } 3446 } 3447 3448 #if IS_ENABLED(CONFIG_BT_SELFTEST_SMP) 3449 3450 static int __init test_debug_key(struct crypto_kpp *tfm_ecdh) 3451 { 3452 u8 pk[64]; 3453 int err; 3454 3455 err = set_ecdh_privkey(tfm_ecdh, debug_sk); 3456 if (err) 3457 return err; 3458 3459 err = generate_ecdh_public_key(tfm_ecdh, pk); 3460 if (err) 3461 return err; 3462 3463 if (crypto_memneq(pk, debug_pk, 64)) 3464 return -EINVAL; 3465 3466 return 0; 3467 } 3468 3469 static int __init test_ah(void) 3470 { 3471 const u8 irk[16] = { 3472 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3473 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3474 const u8 r[3] = { 0x94, 0x81, 0x70 }; 3475 const u8 exp[3] = { 0xaa, 0xfb, 0x0d }; 3476 u8 res[3]; 3477 int err; 3478 3479 err = smp_ah(irk, r, res); 3480 if (err) 3481 return err; 3482 3483 if (crypto_memneq(res, exp, 3)) 3484 return -EINVAL; 3485 3486 return 0; 3487 } 3488 3489 static int __init test_c1(void) 3490 { 3491 const u8 k[16] = { 3492 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3493 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3494 const u8 r[16] = { 3495 0xe0, 0x2e, 0x70, 0xc6, 0x4e, 0x27, 0x88, 0x63, 3496 0x0e, 0x6f, 0xad, 0x56, 0x21, 0xd5, 0x83, 0x57 }; 3497 const u8 preq[7] = { 0x01, 0x01, 0x00, 0x00, 0x10, 0x07, 0x07 }; 3498 const u8 pres[7] = { 0x02, 0x03, 0x00, 0x00, 0x08, 0x00, 0x05 }; 3499 const u8 _iat = 0x01; 3500 const u8 _rat = 0x00; 3501 const bdaddr_t ra = { { 0xb6, 0xb5, 0xb4, 0xb3, 0xb2, 0xb1 } }; 3502 const bdaddr_t ia = { { 0xa6, 0xa5, 0xa4, 0xa3, 0xa2, 0xa1 } }; 3503 const u8 exp[16] = { 3504 0x86, 0x3b, 0xf1, 0xbe, 0xc5, 0x4d, 0xa7, 0xd2, 3505 0xea, 0x88, 0x89, 0x87, 0xef, 0x3f, 0x1e, 0x1e }; 3506 u8 res[16]; 3507 int err; 3508 3509 err = smp_c1(k, r, preq, pres, _iat, &ia, _rat, &ra, res); 3510 if (err) 3511 return err; 3512 3513 if (crypto_memneq(res, exp, 16)) 3514 return -EINVAL; 3515 3516 return 0; 3517 } 3518 3519 static int __init test_s1(void) 3520 { 3521 const u8 k[16] = { 3522 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 3523 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; 3524 const u8 r1[16] = { 3525 0x88, 0x77, 0x66, 0x55, 0x44, 0x33, 0x22, 0x11 }; 3526 const u8 r2[16] = { 3527 0x00, 0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99 }; 3528 const u8 exp[16] = { 3529 0x62, 0xa0, 0x6d, 0x79, 0xae, 0x16, 0x42, 0x5b, 3530 0x9b, 0xf4, 0xb0, 0xe8, 0xf0, 0xe1, 0x1f, 0x9a }; 3531 u8 res[16]; 3532 int err; 3533 3534 err = smp_s1(k, r1, r2, res); 3535 if (err) 3536 return err; 3537 3538 if (crypto_memneq(res, exp, 16)) 3539 return -EINVAL; 3540 3541 return 0; 3542 } 3543 3544 static int __init test_f4(struct crypto_shash *tfm_cmac) 3545 { 3546 const u8 u[32] = { 3547 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3548 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3549 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3550 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3551 const u8 v[32] = { 3552 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3553 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3554 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3555 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3556 const u8 x[16] = { 3557 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3558 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3559 const u8 z = 0x00; 3560 const u8 exp[16] = { 3561 0x2d, 0x87, 0x74, 0xa9, 0xbe, 0xa1, 0xed, 0xf1, 3562 0x1c, 0xbd, 0xa9, 0x07, 0xf1, 0x16, 0xc9, 0xf2 }; 3563 u8 res[16]; 3564 int err; 3565 3566 err = smp_f4(tfm_cmac, u, v, x, z, res); 3567 if (err) 3568 return err; 3569 3570 if (crypto_memneq(res, exp, 16)) 3571 return -EINVAL; 3572 3573 return 0; 3574 } 3575 3576 static int __init test_f5(struct crypto_shash *tfm_cmac) 3577 { 3578 const u8 w[32] = { 3579 0x98, 0xa6, 0xbf, 0x73, 0xf3, 0x34, 0x8d, 0x86, 3580 0xf1, 0x66, 0xf8, 0xb4, 0x13, 0x6b, 0x79, 0x99, 3581 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3582 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3583 const u8 n1[16] = { 3584 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3585 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3586 const u8 n2[16] = { 3587 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3588 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3589 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3590 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3591 const u8 exp_ltk[16] = { 3592 0x38, 0x0a, 0x75, 0x94, 0xb5, 0x22, 0x05, 0x98, 3593 0x23, 0xcd, 0xd7, 0x69, 0x11, 0x79, 0x86, 0x69 }; 3594 const u8 exp_mackey[16] = { 3595 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3596 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3597 u8 mackey[16], ltk[16]; 3598 int err; 3599 3600 err = smp_f5(tfm_cmac, w, n1, n2, a1, a2, mackey, ltk); 3601 if (err) 3602 return err; 3603 3604 if (crypto_memneq(mackey, exp_mackey, 16)) 3605 return -EINVAL; 3606 3607 if (crypto_memneq(ltk, exp_ltk, 16)) 3608 return -EINVAL; 3609 3610 return 0; 3611 } 3612 3613 static int __init test_f6(struct crypto_shash *tfm_cmac) 3614 { 3615 const u8 w[16] = { 3616 0x20, 0x6e, 0x63, 0xce, 0x20, 0x6a, 0x3f, 0xfd, 3617 0x02, 0x4a, 0x08, 0xa1, 0x76, 0xf1, 0x65, 0x29 }; 3618 const u8 n1[16] = { 3619 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3620 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3621 const u8 n2[16] = { 3622 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3623 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3624 const u8 r[16] = { 3625 0xc8, 0x0f, 0x2d, 0x0c, 0xd2, 0x42, 0xda, 0x08, 3626 0x54, 0xbb, 0x53, 0xb4, 0x3b, 0x34, 0xa3, 0x12 }; 3627 const u8 io_cap[3] = { 0x02, 0x01, 0x01 }; 3628 const u8 a1[7] = { 0xce, 0xbf, 0x37, 0x37, 0x12, 0x56, 0x00 }; 3629 const u8 a2[7] = { 0xc1, 0xcf, 0x2d, 0x70, 0x13, 0xa7, 0x00 }; 3630 const u8 exp[16] = { 3631 0x61, 0x8f, 0x95, 0xda, 0x09, 0x0b, 0x6c, 0xd2, 3632 0xc5, 0xe8, 0xd0, 0x9c, 0x98, 0x73, 0xc4, 0xe3 }; 3633 u8 res[16]; 3634 int err; 3635 3636 err = smp_f6(tfm_cmac, w, n1, n2, r, io_cap, a1, a2, res); 3637 if (err) 3638 return err; 3639 3640 if (crypto_memneq(res, exp, 16)) 3641 return -EINVAL; 3642 3643 return 0; 3644 } 3645 3646 static int __init test_g2(struct crypto_shash *tfm_cmac) 3647 { 3648 const u8 u[32] = { 3649 0xe6, 0x9d, 0x35, 0x0e, 0x48, 0x01, 0x03, 0xcc, 3650 0xdb, 0xfd, 0xf4, 0xac, 0x11, 0x91, 0xf4, 0xef, 3651 0xb9, 0xa5, 0xf9, 0xe9, 0xa7, 0x83, 0x2c, 0x5e, 3652 0x2c, 0xbe, 0x97, 0xf2, 0xd2, 0x03, 0xb0, 0x20 }; 3653 const u8 v[32] = { 3654 0xfd, 0xc5, 0x7f, 0xf4, 0x49, 0xdd, 0x4f, 0x6b, 3655 0xfb, 0x7c, 0x9d, 0xf1, 0xc2, 0x9a, 0xcb, 0x59, 3656 0x2a, 0xe7, 0xd4, 0xee, 0xfb, 0xfc, 0x0a, 0x90, 3657 0x9a, 0xbb, 0xf6, 0x32, 0x3d, 0x8b, 0x18, 0x55 }; 3658 const u8 x[16] = { 3659 0xab, 0xae, 0x2b, 0x71, 0xec, 0xb2, 0xff, 0xff, 3660 0x3e, 0x73, 0x77, 0xd1, 0x54, 0x84, 0xcb, 0xd5 }; 3661 const u8 y[16] = { 3662 0xcf, 0xc4, 0x3d, 0xff, 0xf7, 0x83, 0x65, 0x21, 3663 0x6e, 0x5f, 0xa7, 0x25, 0xcc, 0xe7, 0xe8, 0xa6 }; 3664 const u32 exp_val = 0x2f9ed5ba % 1000000; 3665 u32 val; 3666 int err; 3667 3668 err = smp_g2(tfm_cmac, u, v, x, y, &val); 3669 if (err) 3670 return err; 3671 3672 if (val != exp_val) 3673 return -EINVAL; 3674 3675 return 0; 3676 } 3677 3678 static int __init test_h6(struct crypto_shash *tfm_cmac) 3679 { 3680 const u8 w[16] = { 3681 0x9b, 0x7d, 0x39, 0x0a, 0xa6, 0x10, 0x10, 0x34, 3682 0x05, 0xad, 0xc8, 0x57, 0xa3, 0x34, 0x02, 0xec }; 3683 const u8 key_id[4] = { 0x72, 0x62, 0x65, 0x6c }; 3684 const u8 exp[16] = { 3685 0x99, 0x63, 0xb1, 0x80, 0xe2, 0xa9, 0xd3, 0xe8, 3686 0x1c, 0xc9, 0x6d, 0xe7, 0x02, 0xe1, 0x9a, 0x2d }; 3687 u8 res[16]; 3688 int err; 3689 3690 err = smp_h6(tfm_cmac, w, key_id, res); 3691 if (err) 3692 return err; 3693 3694 if (crypto_memneq(res, exp, 16)) 3695 return -EINVAL; 3696 3697 return 0; 3698 } 3699 3700 static char test_smp_buffer[32]; 3701 3702 static ssize_t test_smp_read(struct file *file, char __user *user_buf, 3703 size_t count, loff_t *ppos) 3704 { 3705 return simple_read_from_buffer(user_buf, count, ppos, test_smp_buffer, 3706 strlen(test_smp_buffer)); 3707 } 3708 3709 static const struct file_operations test_smp_fops = { 3710 .open = simple_open, 3711 .read = test_smp_read, 3712 .llseek = default_llseek, 3713 }; 3714 3715 static int __init run_selftests(struct crypto_shash *tfm_cmac, 3716 struct crypto_kpp *tfm_ecdh) 3717 { 3718 ktime_t calltime, delta, rettime; 3719 unsigned long long duration; 3720 int err; 3721 3722 calltime = ktime_get(); 3723 3724 err = test_debug_key(tfm_ecdh); 3725 if (err) { 3726 BT_ERR("debug_key test failed"); 3727 goto done; 3728 } 3729 3730 err = test_ah(); 3731 if (err) { 3732 BT_ERR("smp_ah test failed"); 3733 goto done; 3734 } 3735 3736 err = test_c1(); 3737 if (err) { 3738 BT_ERR("smp_c1 test failed"); 3739 goto done; 3740 } 3741 3742 err = test_s1(); 3743 if (err) { 3744 BT_ERR("smp_s1 test failed"); 3745 goto done; 3746 } 3747 3748 err = test_f4(tfm_cmac); 3749 if (err) { 3750 BT_ERR("smp_f4 test failed"); 3751 goto done; 3752 } 3753 3754 err = test_f5(tfm_cmac); 3755 if (err) { 3756 BT_ERR("smp_f5 test failed"); 3757 goto done; 3758 } 3759 3760 err = test_f6(tfm_cmac); 3761 if (err) { 3762 BT_ERR("smp_f6 test failed"); 3763 goto done; 3764 } 3765 3766 err = test_g2(tfm_cmac); 3767 if (err) { 3768 BT_ERR("smp_g2 test failed"); 3769 goto done; 3770 } 3771 3772 err = test_h6(tfm_cmac); 3773 if (err) { 3774 BT_ERR("smp_h6 test failed"); 3775 goto done; 3776 } 3777 3778 rettime = ktime_get(); 3779 delta = ktime_sub(rettime, calltime); 3780 duration = (unsigned long long) ktime_to_ns(delta) >> 10; 3781 3782 BT_INFO("SMP test passed in %llu usecs", duration); 3783 3784 done: 3785 if (!err) 3786 snprintf(test_smp_buffer, sizeof(test_smp_buffer), 3787 "PASS (%llu usecs)\n", duration); 3788 else 3789 snprintf(test_smp_buffer, sizeof(test_smp_buffer), "FAIL\n"); 3790 3791 debugfs_create_file("selftest_smp", 0444, bt_debugfs, NULL, 3792 &test_smp_fops); 3793 3794 return err; 3795 } 3796 3797 int __init bt_selftest_smp(void) 3798 { 3799 struct crypto_shash *tfm_cmac; 3800 struct crypto_kpp *tfm_ecdh; 3801 int err; 3802 3803 tfm_cmac = crypto_alloc_shash("cmac(aes)", 0, 0); 3804 if (IS_ERR(tfm_cmac)) { 3805 BT_ERR("Unable to create CMAC crypto context"); 3806 return PTR_ERR(tfm_cmac); 3807 } 3808 3809 tfm_ecdh = crypto_alloc_kpp("ecdh", 0, 0); 3810 if (IS_ERR(tfm_ecdh)) { 3811 BT_ERR("Unable to create ECDH crypto context"); 3812 crypto_free_shash(tfm_cmac); 3813 return PTR_ERR(tfm_ecdh); 3814 } 3815 3816 err = run_selftests(tfm_cmac, tfm_ecdh); 3817 3818 crypto_free_shash(tfm_cmac); 3819 crypto_free_kpp(tfm_ecdh); 3820 3821 return err; 3822 } 3823 3824 #endif 3825