1 2 #include <linux/ceph/ceph_debug.h> 3 4 #include <linux/err.h> 5 #include <linux/module.h> 6 #include <linux/random.h> 7 #include <linux/slab.h> 8 9 #include <linux/ceph/decode.h> 10 #include <linux/ceph/auth.h> 11 12 #include "crypto.h" 13 #include "auth_x.h" 14 #include "auth_x_protocol.h" 15 16 #define TEMP_TICKET_BUF_LEN 256 17 18 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed); 19 20 static int ceph_x_is_authenticated(struct ceph_auth_client *ac) 21 { 22 struct ceph_x_info *xi = ac->private; 23 int need; 24 25 ceph_x_validate_tickets(ac, &need); 26 dout("ceph_x_is_authenticated want=%d need=%d have=%d\n", 27 ac->want_keys, need, xi->have_keys); 28 return (ac->want_keys & xi->have_keys) == ac->want_keys; 29 } 30 31 static int ceph_x_should_authenticate(struct ceph_auth_client *ac) 32 { 33 struct ceph_x_info *xi = ac->private; 34 int need; 35 36 ceph_x_validate_tickets(ac, &need); 37 dout("ceph_x_should_authenticate want=%d need=%d have=%d\n", 38 ac->want_keys, need, xi->have_keys); 39 return need != 0; 40 } 41 42 static int ceph_x_encrypt_buflen(int ilen) 43 { 44 return sizeof(struct ceph_x_encrypt_header) + ilen + 16 + 45 sizeof(u32); 46 } 47 48 static int ceph_x_encrypt(struct ceph_crypto_key *secret, 49 void *ibuf, int ilen, void *obuf, size_t olen) 50 { 51 struct ceph_x_encrypt_header head = { 52 .struct_v = 1, 53 .magic = cpu_to_le64(CEPHX_ENC_MAGIC) 54 }; 55 size_t len = olen - sizeof(u32); 56 int ret; 57 58 ret = ceph_encrypt2(secret, obuf + sizeof(u32), &len, 59 &head, sizeof(head), ibuf, ilen); 60 if (ret) 61 return ret; 62 ceph_encode_32(&obuf, len); 63 return len + sizeof(u32); 64 } 65 66 static int ceph_x_decrypt(struct ceph_crypto_key *secret, 67 void **p, void *end, void *obuf, size_t olen) 68 { 69 struct ceph_x_encrypt_header head; 70 size_t head_len = sizeof(head); 71 int len, ret; 72 73 len = ceph_decode_32(p); 74 if (*p + len > end) 75 return -EINVAL; 76 77 dout("ceph_x_decrypt len %d\n", len); 78 ret = ceph_decrypt2(secret, &head, &head_len, obuf, &olen, 79 *p, len); 80 if (ret) 81 return ret; 82 if (head.struct_v != 1 || le64_to_cpu(head.magic) != CEPHX_ENC_MAGIC) 83 return -EPERM; 84 *p += len; 85 return olen; 86 } 87 88 /* 89 * get existing (or insert new) ticket handler 90 */ 91 static struct ceph_x_ticket_handler * 92 get_ticket_handler(struct ceph_auth_client *ac, int service) 93 { 94 struct ceph_x_ticket_handler *th; 95 struct ceph_x_info *xi = ac->private; 96 struct rb_node *parent = NULL, **p = &xi->ticket_handlers.rb_node; 97 98 while (*p) { 99 parent = *p; 100 th = rb_entry(parent, struct ceph_x_ticket_handler, node); 101 if (service < th->service) 102 p = &(*p)->rb_left; 103 else if (service > th->service) 104 p = &(*p)->rb_right; 105 else 106 return th; 107 } 108 109 /* add it */ 110 th = kzalloc(sizeof(*th), GFP_NOFS); 111 if (!th) 112 return ERR_PTR(-ENOMEM); 113 th->service = service; 114 rb_link_node(&th->node, parent, p); 115 rb_insert_color(&th->node, &xi->ticket_handlers); 116 return th; 117 } 118 119 static void remove_ticket_handler(struct ceph_auth_client *ac, 120 struct ceph_x_ticket_handler *th) 121 { 122 struct ceph_x_info *xi = ac->private; 123 124 dout("remove_ticket_handler %p %d\n", th, th->service); 125 rb_erase(&th->node, &xi->ticket_handlers); 126 ceph_crypto_key_destroy(&th->session_key); 127 if (th->ticket_blob) 128 ceph_buffer_put(th->ticket_blob); 129 kfree(th); 130 } 131 132 static int ceph_x_proc_ticket_reply(struct ceph_auth_client *ac, 133 struct ceph_crypto_key *secret, 134 void *buf, void *end) 135 { 136 struct ceph_x_info *xi = ac->private; 137 int num; 138 void *p = buf; 139 int ret; 140 char *dbuf; 141 char *ticket_buf; 142 u8 reply_struct_v; 143 144 dbuf = kmalloc(TEMP_TICKET_BUF_LEN, GFP_NOFS); 145 if (!dbuf) 146 return -ENOMEM; 147 148 ret = -ENOMEM; 149 ticket_buf = kmalloc(TEMP_TICKET_BUF_LEN, GFP_NOFS); 150 if (!ticket_buf) 151 goto out_dbuf; 152 153 ceph_decode_need(&p, end, 1 + sizeof(u32), bad); 154 reply_struct_v = ceph_decode_8(&p); 155 if (reply_struct_v != 1) 156 goto bad; 157 num = ceph_decode_32(&p); 158 dout("%d tickets\n", num); 159 while (num--) { 160 int type; 161 u8 tkt_struct_v, blob_struct_v; 162 struct ceph_x_ticket_handler *th; 163 void *dp, *dend; 164 int dlen; 165 char is_enc; 166 struct timespec validity; 167 struct ceph_crypto_key old_key; 168 void *tp, *tpend; 169 struct ceph_timespec new_validity; 170 struct ceph_crypto_key new_session_key; 171 struct ceph_buffer *new_ticket_blob; 172 unsigned long new_expires, new_renew_after; 173 u64 new_secret_id; 174 175 ceph_decode_need(&p, end, sizeof(u32) + 1, bad); 176 177 type = ceph_decode_32(&p); 178 dout(" ticket type %d %s\n", type, ceph_entity_type_name(type)); 179 180 tkt_struct_v = ceph_decode_8(&p); 181 if (tkt_struct_v != 1) 182 goto bad; 183 184 th = get_ticket_handler(ac, type); 185 if (IS_ERR(th)) { 186 ret = PTR_ERR(th); 187 goto out; 188 } 189 190 /* blob for me */ 191 dlen = ceph_x_decrypt(secret, &p, end, dbuf, 192 TEMP_TICKET_BUF_LEN); 193 if (dlen <= 0) { 194 ret = dlen; 195 goto out; 196 } 197 dout(" decrypted %d bytes\n", dlen); 198 dend = dbuf + dlen; 199 dp = dbuf; 200 201 tkt_struct_v = ceph_decode_8(&dp); 202 if (tkt_struct_v != 1) 203 goto bad; 204 205 memcpy(&old_key, &th->session_key, sizeof(old_key)); 206 ret = ceph_crypto_key_decode(&new_session_key, &dp, dend); 207 if (ret) 208 goto out; 209 210 ceph_decode_copy(&dp, &new_validity, sizeof(new_validity)); 211 ceph_decode_timespec(&validity, &new_validity); 212 new_expires = get_seconds() + validity.tv_sec; 213 new_renew_after = new_expires - (validity.tv_sec / 4); 214 dout(" expires=%lu renew_after=%lu\n", new_expires, 215 new_renew_after); 216 217 /* ticket blob for service */ 218 ceph_decode_8_safe(&p, end, is_enc, bad); 219 tp = ticket_buf; 220 if (is_enc) { 221 /* encrypted */ 222 dout(" encrypted ticket\n"); 223 dlen = ceph_x_decrypt(&old_key, &p, end, ticket_buf, 224 TEMP_TICKET_BUF_LEN); 225 if (dlen < 0) { 226 ret = dlen; 227 goto out; 228 } 229 dlen = ceph_decode_32(&tp); 230 } else { 231 /* unencrypted */ 232 ceph_decode_32_safe(&p, end, dlen, bad); 233 ceph_decode_need(&p, end, dlen, bad); 234 ceph_decode_copy(&p, ticket_buf, dlen); 235 } 236 tpend = tp + dlen; 237 dout(" ticket blob is %d bytes\n", dlen); 238 ceph_decode_need(&tp, tpend, 1 + sizeof(u64), bad); 239 blob_struct_v = ceph_decode_8(&tp); 240 new_secret_id = ceph_decode_64(&tp); 241 ret = ceph_decode_buffer(&new_ticket_blob, &tp, tpend); 242 if (ret) 243 goto out; 244 245 /* all is well, update our ticket */ 246 ceph_crypto_key_destroy(&th->session_key); 247 if (th->ticket_blob) 248 ceph_buffer_put(th->ticket_blob); 249 th->session_key = new_session_key; 250 th->ticket_blob = new_ticket_blob; 251 th->validity = new_validity; 252 th->secret_id = new_secret_id; 253 th->expires = new_expires; 254 th->renew_after = new_renew_after; 255 dout(" got ticket service %d (%s) secret_id %lld len %d\n", 256 type, ceph_entity_type_name(type), th->secret_id, 257 (int)th->ticket_blob->vec.iov_len); 258 xi->have_keys |= th->service; 259 } 260 261 ret = 0; 262 out: 263 kfree(ticket_buf); 264 out_dbuf: 265 kfree(dbuf); 266 return ret; 267 268 bad: 269 ret = -EINVAL; 270 goto out; 271 } 272 273 static int ceph_x_build_authorizer(struct ceph_auth_client *ac, 274 struct ceph_x_ticket_handler *th, 275 struct ceph_x_authorizer *au) 276 { 277 int maxlen; 278 struct ceph_x_authorize_a *msg_a; 279 struct ceph_x_authorize_b msg_b; 280 void *p, *end; 281 int ret; 282 int ticket_blob_len = 283 (th->ticket_blob ? th->ticket_blob->vec.iov_len : 0); 284 285 dout("build_authorizer for %s %p\n", 286 ceph_entity_type_name(th->service), au); 287 288 maxlen = sizeof(*msg_a) + sizeof(msg_b) + 289 ceph_x_encrypt_buflen(ticket_blob_len); 290 dout(" need len %d\n", maxlen); 291 if (au->buf && au->buf->alloc_len < maxlen) { 292 ceph_buffer_put(au->buf); 293 au->buf = NULL; 294 } 295 if (!au->buf) { 296 au->buf = ceph_buffer_new(maxlen, GFP_NOFS); 297 if (!au->buf) 298 return -ENOMEM; 299 } 300 au->service = th->service; 301 302 msg_a = au->buf->vec.iov_base; 303 msg_a->struct_v = 1; 304 msg_a->global_id = cpu_to_le64(ac->global_id); 305 msg_a->service_id = cpu_to_le32(th->service); 306 msg_a->ticket_blob.struct_v = 1; 307 msg_a->ticket_blob.secret_id = cpu_to_le64(th->secret_id); 308 msg_a->ticket_blob.blob_len = cpu_to_le32(ticket_blob_len); 309 if (ticket_blob_len) { 310 memcpy(msg_a->ticket_blob.blob, th->ticket_blob->vec.iov_base, 311 th->ticket_blob->vec.iov_len); 312 } 313 dout(" th %p secret_id %lld %lld\n", th, th->secret_id, 314 le64_to_cpu(msg_a->ticket_blob.secret_id)); 315 316 p = msg_a + 1; 317 p += ticket_blob_len; 318 end = au->buf->vec.iov_base + au->buf->vec.iov_len; 319 320 get_random_bytes(&au->nonce, sizeof(au->nonce)); 321 msg_b.struct_v = 1; 322 msg_b.nonce = cpu_to_le64(au->nonce); 323 ret = ceph_x_encrypt(&th->session_key, &msg_b, sizeof(msg_b), 324 p, end - p); 325 if (ret < 0) 326 goto out_buf; 327 p += ret; 328 au->buf->vec.iov_len = p - au->buf->vec.iov_base; 329 dout(" built authorizer nonce %llx len %d\n", au->nonce, 330 (int)au->buf->vec.iov_len); 331 BUG_ON(au->buf->vec.iov_len > maxlen); 332 return 0; 333 334 out_buf: 335 ceph_buffer_put(au->buf); 336 au->buf = NULL; 337 return ret; 338 } 339 340 static int ceph_x_encode_ticket(struct ceph_x_ticket_handler *th, 341 void **p, void *end) 342 { 343 ceph_decode_need(p, end, 1 + sizeof(u64), bad); 344 ceph_encode_8(p, 1); 345 ceph_encode_64(p, th->secret_id); 346 if (th->ticket_blob) { 347 const char *buf = th->ticket_blob->vec.iov_base; 348 u32 len = th->ticket_blob->vec.iov_len; 349 350 ceph_encode_32_safe(p, end, len, bad); 351 ceph_encode_copy_safe(p, end, buf, len, bad); 352 } else { 353 ceph_encode_32_safe(p, end, 0, bad); 354 } 355 356 return 0; 357 bad: 358 return -ERANGE; 359 } 360 361 static void ceph_x_validate_tickets(struct ceph_auth_client *ac, int *pneed) 362 { 363 int want = ac->want_keys; 364 struct ceph_x_info *xi = ac->private; 365 int service; 366 367 *pneed = ac->want_keys & ~(xi->have_keys); 368 369 for (service = 1; service <= want; service <<= 1) { 370 struct ceph_x_ticket_handler *th; 371 372 if (!(ac->want_keys & service)) 373 continue; 374 375 if (*pneed & service) 376 continue; 377 378 th = get_ticket_handler(ac, service); 379 380 if (IS_ERR(th)) { 381 *pneed |= service; 382 continue; 383 } 384 385 if (get_seconds() >= th->renew_after) 386 *pneed |= service; 387 if (get_seconds() >= th->expires) 388 xi->have_keys &= ~service; 389 } 390 } 391 392 393 static int ceph_x_build_request(struct ceph_auth_client *ac, 394 void *buf, void *end) 395 { 396 struct ceph_x_info *xi = ac->private; 397 int need; 398 struct ceph_x_request_header *head = buf; 399 int ret; 400 struct ceph_x_ticket_handler *th = 401 get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH); 402 403 if (IS_ERR(th)) 404 return PTR_ERR(th); 405 406 ceph_x_validate_tickets(ac, &need); 407 408 dout("build_request want %x have %x need %x\n", 409 ac->want_keys, xi->have_keys, need); 410 411 if (need & CEPH_ENTITY_TYPE_AUTH) { 412 struct ceph_x_authenticate *auth = (void *)(head + 1); 413 void *p = auth + 1; 414 struct ceph_x_challenge_blob tmp; 415 char tmp_enc[40]; 416 u64 *u; 417 418 if (p > end) 419 return -ERANGE; 420 421 dout(" get_auth_session_key\n"); 422 head->op = cpu_to_le16(CEPHX_GET_AUTH_SESSION_KEY); 423 424 /* encrypt and hash */ 425 get_random_bytes(&auth->client_challenge, sizeof(u64)); 426 tmp.client_challenge = auth->client_challenge; 427 tmp.server_challenge = cpu_to_le64(xi->server_challenge); 428 ret = ceph_x_encrypt(&xi->secret, &tmp, sizeof(tmp), 429 tmp_enc, sizeof(tmp_enc)); 430 if (ret < 0) 431 return ret; 432 433 auth->struct_v = 1; 434 auth->key = 0; 435 for (u = (u64 *)tmp_enc; u + 1 <= (u64 *)(tmp_enc + ret); u++) 436 auth->key ^= *(__le64 *)u; 437 dout(" server_challenge %llx client_challenge %llx key %llx\n", 438 xi->server_challenge, le64_to_cpu(auth->client_challenge), 439 le64_to_cpu(auth->key)); 440 441 /* now encode the old ticket if exists */ 442 ret = ceph_x_encode_ticket(th, &p, end); 443 if (ret < 0) 444 return ret; 445 446 return p - buf; 447 } 448 449 if (need) { 450 void *p = head + 1; 451 struct ceph_x_service_ticket_request *req; 452 453 if (p > end) 454 return -ERANGE; 455 head->op = cpu_to_le16(CEPHX_GET_PRINCIPAL_SESSION_KEY); 456 457 ret = ceph_x_build_authorizer(ac, th, &xi->auth_authorizer); 458 if (ret) 459 return ret; 460 ceph_encode_copy(&p, xi->auth_authorizer.buf->vec.iov_base, 461 xi->auth_authorizer.buf->vec.iov_len); 462 463 req = p; 464 req->keys = cpu_to_le32(need); 465 p += sizeof(*req); 466 return p - buf; 467 } 468 469 return 0; 470 } 471 472 static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result, 473 void *buf, void *end) 474 { 475 struct ceph_x_info *xi = ac->private; 476 struct ceph_x_reply_header *head = buf; 477 struct ceph_x_ticket_handler *th; 478 int len = end - buf; 479 int op; 480 int ret; 481 482 if (result) 483 return result; /* XXX hmm? */ 484 485 if (xi->starting) { 486 /* it's a hello */ 487 struct ceph_x_server_challenge *sc = buf; 488 489 if (len != sizeof(*sc)) 490 return -EINVAL; 491 xi->server_challenge = le64_to_cpu(sc->server_challenge); 492 dout("handle_reply got server challenge %llx\n", 493 xi->server_challenge); 494 xi->starting = false; 495 xi->have_keys &= ~CEPH_ENTITY_TYPE_AUTH; 496 return -EAGAIN; 497 } 498 499 op = le16_to_cpu(head->op); 500 result = le32_to_cpu(head->result); 501 dout("handle_reply op %d result %d\n", op, result); 502 switch (op) { 503 case CEPHX_GET_AUTH_SESSION_KEY: 504 /* verify auth key */ 505 ret = ceph_x_proc_ticket_reply(ac, &xi->secret, 506 buf + sizeof(*head), end); 507 break; 508 509 case CEPHX_GET_PRINCIPAL_SESSION_KEY: 510 th = get_ticket_handler(ac, CEPH_ENTITY_TYPE_AUTH); 511 if (IS_ERR(th)) 512 return PTR_ERR(th); 513 ret = ceph_x_proc_ticket_reply(ac, &th->session_key, 514 buf + sizeof(*head), end); 515 break; 516 517 default: 518 return -EINVAL; 519 } 520 if (ret) 521 return ret; 522 if (ac->want_keys == xi->have_keys) 523 return 0; 524 return -EAGAIN; 525 } 526 527 static int ceph_x_create_authorizer( 528 struct ceph_auth_client *ac, int peer_type, 529 struct ceph_auth_handshake *auth) 530 { 531 struct ceph_x_authorizer *au; 532 struct ceph_x_ticket_handler *th; 533 int ret; 534 535 th = get_ticket_handler(ac, peer_type); 536 if (IS_ERR(th)) 537 return PTR_ERR(th); 538 539 au = kzalloc(sizeof(*au), GFP_NOFS); 540 if (!au) 541 return -ENOMEM; 542 543 ret = ceph_x_build_authorizer(ac, th, au); 544 if (ret) { 545 kfree(au); 546 return ret; 547 } 548 549 auth->authorizer = (struct ceph_authorizer *) au; 550 auth->authorizer_buf = au->buf->vec.iov_base; 551 auth->authorizer_buf_len = au->buf->vec.iov_len; 552 auth->authorizer_reply_buf = au->reply_buf; 553 auth->authorizer_reply_buf_len = sizeof (au->reply_buf); 554 555 return 0; 556 } 557 558 static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac, 559 struct ceph_authorizer *a, size_t len) 560 { 561 struct ceph_x_authorizer *au = (void *)a; 562 struct ceph_x_ticket_handler *th; 563 int ret = 0; 564 struct ceph_x_authorize_reply reply; 565 void *p = au->reply_buf; 566 void *end = p + sizeof(au->reply_buf); 567 568 th = get_ticket_handler(ac, au->service); 569 if (IS_ERR(th)) 570 return PTR_ERR(th); 571 ret = ceph_x_decrypt(&th->session_key, &p, end, &reply, sizeof(reply)); 572 if (ret < 0) 573 return ret; 574 if (ret != sizeof(reply)) 575 return -EPERM; 576 577 if (au->nonce + 1 != le64_to_cpu(reply.nonce_plus_one)) 578 ret = -EPERM; 579 else 580 ret = 0; 581 dout("verify_authorizer_reply nonce %llx got %llx ret %d\n", 582 au->nonce, le64_to_cpu(reply.nonce_plus_one), ret); 583 return ret; 584 } 585 586 static void ceph_x_destroy_authorizer(struct ceph_auth_client *ac, 587 struct ceph_authorizer *a) 588 { 589 struct ceph_x_authorizer *au = (void *)a; 590 591 ceph_buffer_put(au->buf); 592 kfree(au); 593 } 594 595 596 static void ceph_x_reset(struct ceph_auth_client *ac) 597 { 598 struct ceph_x_info *xi = ac->private; 599 600 dout("reset\n"); 601 xi->starting = true; 602 xi->server_challenge = 0; 603 } 604 605 static void ceph_x_destroy(struct ceph_auth_client *ac) 606 { 607 struct ceph_x_info *xi = ac->private; 608 struct rb_node *p; 609 610 dout("ceph_x_destroy %p\n", ac); 611 ceph_crypto_key_destroy(&xi->secret); 612 613 while ((p = rb_first(&xi->ticket_handlers)) != NULL) { 614 struct ceph_x_ticket_handler *th = 615 rb_entry(p, struct ceph_x_ticket_handler, node); 616 remove_ticket_handler(ac, th); 617 } 618 619 if (xi->auth_authorizer.buf) 620 ceph_buffer_put(xi->auth_authorizer.buf); 621 622 kfree(ac->private); 623 ac->private = NULL; 624 } 625 626 static void ceph_x_invalidate_authorizer(struct ceph_auth_client *ac, 627 int peer_type) 628 { 629 struct ceph_x_ticket_handler *th; 630 631 th = get_ticket_handler(ac, peer_type); 632 if (!IS_ERR(th)) 633 remove_ticket_handler(ac, th); 634 } 635 636 637 static const struct ceph_auth_client_ops ceph_x_ops = { 638 .name = "x", 639 .is_authenticated = ceph_x_is_authenticated, 640 .should_authenticate = ceph_x_should_authenticate, 641 .build_request = ceph_x_build_request, 642 .handle_reply = ceph_x_handle_reply, 643 .create_authorizer = ceph_x_create_authorizer, 644 .verify_authorizer_reply = ceph_x_verify_authorizer_reply, 645 .destroy_authorizer = ceph_x_destroy_authorizer, 646 .invalidate_authorizer = ceph_x_invalidate_authorizer, 647 .reset = ceph_x_reset, 648 .destroy = ceph_x_destroy, 649 }; 650 651 652 int ceph_x_init(struct ceph_auth_client *ac) 653 { 654 struct ceph_x_info *xi; 655 int ret; 656 657 dout("ceph_x_init %p\n", ac); 658 ret = -ENOMEM; 659 xi = kzalloc(sizeof(*xi), GFP_NOFS); 660 if (!xi) 661 goto out; 662 663 ret = -EINVAL; 664 if (!ac->key) { 665 pr_err("no secret set (for auth_x protocol)\n"); 666 goto out_nomem; 667 } 668 669 ret = ceph_crypto_key_clone(&xi->secret, ac->key); 670 if (ret < 0) { 671 pr_err("cannot clone key: %d\n", ret); 672 goto out_nomem; 673 } 674 675 xi->starting = true; 676 xi->ticket_handlers = RB_ROOT; 677 678 ac->protocol = CEPH_AUTH_CEPHX; 679 ac->private = xi; 680 ac->ops = &ceph_x_ops; 681 return 0; 682 683 out_nomem: 684 kfree(xi); 685 out: 686 return ret; 687 } 688 689 690