1/*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2012 The FreeBSD Foundation 5 * 6 * This software was developed by Edward Tomasz Napierala under sponsorship 7 * from the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD$"); 34 35#include <assert.h> 36#include <stdbool.h> 37#include <stdlib.h> 38#include <string.h> 39#include <unistd.h> 40#include <netinet/in.h> 41 42#include "ctld.h" 43#include "iscsi_proto.h" 44 45static void login_send_error(struct pdu *request, 46 char class, char detail); 47 48static void 49login_set_nsg(struct pdu *response, int nsg) 50{ 51 struct iscsi_bhs_login_response *bhslr; 52 53 assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION || 54 nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION || 55 nsg == BHSLR_STAGE_FULL_FEATURE_PHASE); 56 57 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 58 59 bhslr->bhslr_flags &= 0xFC; 60 bhslr->bhslr_flags |= nsg; 61 bhslr->bhslr_flags |= BHSLR_FLAGS_TRANSIT; 62} 63 64static int 65login_csg(const struct pdu *request) 66{ 67 struct iscsi_bhs_login_request *bhslr; 68 69 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 70 71 return ((bhslr->bhslr_flags & 0x0C) >> 2); 72} 73 74static void 75login_set_csg(struct pdu *response, int csg) 76{ 77 struct iscsi_bhs_login_response *bhslr; 78 79 assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION || 80 csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION || 81 csg == BHSLR_STAGE_FULL_FEATURE_PHASE); 82 83 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 84 85 bhslr->bhslr_flags &= 0xF3; 86 bhslr->bhslr_flags |= csg << 2; 87} 88 89static struct pdu * 90login_receive(struct connection *conn, bool initial) 91{ 92 struct pdu *request; 93 struct iscsi_bhs_login_request *bhslr; 94 95 request = pdu_new(conn); 96 pdu_receive(request); 97 if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) != 98 ISCSI_BHS_OPCODE_LOGIN_REQUEST) { 99 /* 100 * The first PDU in session is special - if we receive any PDU 101 * different than login request, we have to drop the connection 102 * without sending response ("A target receiving any PDU 103 * except a Login request before the Login Phase is started MUST 104 * immediately terminate the connection on which the PDU 105 * was received.") 106 */ 107 if (initial == false) 108 login_send_error(request, 0x02, 0x0b); 109 log_errx(1, "protocol error: received invalid opcode 0x%x", 110 request->pdu_bhs->bhs_opcode); 111 } 112 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 113 /* 114 * XXX: Implement the C flag some day. 115 */ 116 if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) { 117 login_send_error(request, 0x03, 0x00); 118 log_errx(1, "received Login PDU with unsupported \"C\" flag"); 119 } 120 if (bhslr->bhslr_version_max != 0x00) { 121 login_send_error(request, 0x02, 0x05); 122 log_errx(1, "received Login PDU with unsupported " 123 "Version-max 0x%x", bhslr->bhslr_version_max); 124 } 125 if (bhslr->bhslr_version_min != 0x00) { 126 login_send_error(request, 0x02, 0x05); 127 log_errx(1, "received Login PDU with unsupported " 128 "Version-min 0x%x", bhslr->bhslr_version_min); 129 } 130 if (initial == false && 131 ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) { 132 login_send_error(request, 0x02, 0x00); 133 log_errx(1, "received Login PDU with decreasing CmdSN: " 134 "was %u, is %u", conn->conn_cmdsn, 135 ntohl(bhslr->bhslr_cmdsn)); 136 } 137 if (initial == false && 138 ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) { 139 login_send_error(request, 0x02, 0x00); 140 log_errx(1, "received Login PDU with wrong ExpStatSN: " 141 "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn), 142 conn->conn_statsn); 143 } 144 conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn); 145 146 return (request); 147} 148 149static struct pdu * 150login_new_response(struct pdu *request) 151{ 152 struct pdu *response; 153 struct connection *conn; 154 struct iscsi_bhs_login_request *bhslr; 155 struct iscsi_bhs_login_response *bhslr2; 156 157 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 158 conn = request->pdu_connection; 159 160 response = pdu_new_response(request); 161 bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs; 162 bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_RESPONSE; 163 login_set_csg(response, BHSLR_STAGE_SECURITY_NEGOTIATION); 164 memcpy(bhslr2->bhslr_isid, 165 bhslr->bhslr_isid, sizeof(bhslr2->bhslr_isid)); 166 bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag; 167 bhslr2->bhslr_statsn = htonl(conn->conn_statsn++); 168 bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn); 169 bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn); 170 171 return (response); 172} 173 174static void 175login_send_error(struct pdu *request, char class, char detail) 176{ 177 struct pdu *response; 178 struct iscsi_bhs_login_response *bhslr2; 179 180 log_debugx("sending Login Response PDU with failure class 0x%x/0x%x; " 181 "see next line for reason", class, detail); 182 response = login_new_response(request); 183 bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs; 184 bhslr2->bhslr_status_class = class; 185 bhslr2->bhslr_status_detail = detail; 186 187 pdu_send(response); 188 pdu_delete(response); 189} 190 191static int 192login_list_contains(const char *list, const char *what) 193{ 194 char *tofree, *str, *token; 195 196 tofree = str = checked_strdup(list); 197 198 while ((token = strsep(&str, ",")) != NULL) { 199 if (strcmp(token, what) == 0) { 200 free(tofree); 201 return (1); 202 } 203 } 204 free(tofree); 205 return (0); 206} 207 208static int 209login_list_prefers(const char *list, 210 const char *choice1, const char *choice2) 211{ 212 char *tofree, *str, *token; 213 214 tofree = str = checked_strdup(list); 215 216 while ((token = strsep(&str, ",")) != NULL) { 217 if (strcmp(token, choice1) == 0) { 218 free(tofree); 219 return (1); 220 } 221 if (strcmp(token, choice2) == 0) { 222 free(tofree); 223 return (2); 224 } 225 } 226 free(tofree); 227 return (-1); 228} 229 230static struct pdu * 231login_receive_chap_a(struct connection *conn) 232{ 233 struct pdu *request; 234 struct keys *request_keys; 235 const char *chap_a; 236 237 request = login_receive(conn, false); 238 request_keys = keys_new(); 239 keys_load(request_keys, request); 240 241 chap_a = keys_find(request_keys, "CHAP_A"); 242 if (chap_a == NULL) { 243 login_send_error(request, 0x02, 0x07); 244 log_errx(1, "received CHAP Login PDU without CHAP_A"); 245 } 246 if (login_list_contains(chap_a, "5") == 0) { 247 login_send_error(request, 0x02, 0x01); 248 log_errx(1, "received CHAP Login PDU with unsupported CHAP_A " 249 "\"%s\"", chap_a); 250 } 251 keys_delete(request_keys); 252 253 return (request); 254} 255 256static void 257login_send_chap_c(struct pdu *request, struct chap *chap) 258{ 259 struct pdu *response; 260 struct keys *response_keys; 261 char *chap_c, *chap_i; 262 263 chap_c = chap_get_challenge(chap); 264 chap_i = chap_get_id(chap); 265 266 response = login_new_response(request); 267 response_keys = keys_new(); 268 keys_add(response_keys, "CHAP_A", "5"); 269 keys_add(response_keys, "CHAP_I", chap_i); 270 keys_add(response_keys, "CHAP_C", chap_c); 271 free(chap_i); 272 free(chap_c); 273 keys_save(response_keys, response); 274 pdu_send(response); 275 pdu_delete(response); 276 keys_delete(response_keys); 277} 278 279static struct pdu * 280login_receive_chap_r(struct connection *conn, struct auth_group *ag, 281 struct chap *chap, const struct auth **authp) 282{ 283 struct pdu *request; 284 struct keys *request_keys; 285 const char *chap_n, *chap_r; 286 const struct auth *auth; 287 int error; 288 289 request = login_receive(conn, false); 290 request_keys = keys_new(); 291 keys_load(request_keys, request); 292 293 chap_n = keys_find(request_keys, "CHAP_N"); 294 if (chap_n == NULL) { 295 login_send_error(request, 0x02, 0x07); 296 log_errx(1, "received CHAP Login PDU without CHAP_N"); 297 } 298 chap_r = keys_find(request_keys, "CHAP_R"); 299 if (chap_r == NULL) { 300 login_send_error(request, 0x02, 0x07); 301 log_errx(1, "received CHAP Login PDU without CHAP_R"); 302 } 303 error = chap_receive(chap, chap_r); 304 if (error != 0) { 305 login_send_error(request, 0x02, 0x07); 306 log_errx(1, "received CHAP Login PDU with malformed CHAP_R"); 307 } 308 309 /* 310 * Verify the response. 311 */ 312 assert(ag->ag_type == AG_TYPE_CHAP || 313 ag->ag_type == AG_TYPE_CHAP_MUTUAL); 314 auth = auth_find(ag, chap_n); 315 if (auth == NULL) { 316 login_send_error(request, 0x02, 0x01); 317 log_errx(1, "received CHAP Login with invalid user \"%s\"", 318 chap_n); 319 } 320 321 assert(auth->a_secret != NULL); 322 assert(strlen(auth->a_secret) > 0); 323 324 error = chap_authenticate(chap, auth->a_secret); 325 if (error != 0) { 326 login_send_error(request, 0x02, 0x01); 327 log_errx(1, "CHAP authentication failed for user \"%s\"", 328 auth->a_user); 329 } 330 331 keys_delete(request_keys); 332 333 *authp = auth; 334 return (request); 335} 336 337static void 338login_send_chap_success(struct pdu *request, 339 const struct auth *auth) 340{ 341 struct pdu *response; 342 struct keys *request_keys, *response_keys; 343 struct rchap *rchap; 344 const char *chap_i, *chap_c; 345 char *chap_r; 346 int error; 347 348 response = login_new_response(request); 349 login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 350 351 /* 352 * Actually, one more thing: mutual authentication. 353 */ 354 request_keys = keys_new(); 355 keys_load(request_keys, request); 356 chap_i = keys_find(request_keys, "CHAP_I"); 357 chap_c = keys_find(request_keys, "CHAP_C"); 358 if (chap_i != NULL || chap_c != NULL) { 359 if (chap_i == NULL) { 360 login_send_error(request, 0x02, 0x07); 361 log_errx(1, "initiator requested target " 362 "authentication, but didn't send CHAP_I"); 363 } 364 if (chap_c == NULL) { 365 login_send_error(request, 0x02, 0x07); 366 log_errx(1, "initiator requested target " 367 "authentication, but didn't send CHAP_C"); 368 } 369 if (auth->a_auth_group->ag_type != AG_TYPE_CHAP_MUTUAL) { 370 login_send_error(request, 0x02, 0x01); 371 log_errx(1, "initiator requests target authentication " 372 "for user \"%s\", but mutual user/secret " 373 "is not set", auth->a_user); 374 } 375 376 log_debugx("performing mutual authentication as user \"%s\"", 377 auth->a_mutual_user); 378 379 rchap = rchap_new(auth->a_mutual_secret); 380 error = rchap_receive(rchap, chap_i, chap_c); 381 if (error != 0) { 382 login_send_error(request, 0x02, 0x07); 383 log_errx(1, "received CHAP Login PDU with malformed " 384 "CHAP_I or CHAP_C"); 385 } 386 chap_r = rchap_get_response(rchap); 387 rchap_delete(rchap); 388 response_keys = keys_new(); 389 keys_add(response_keys, "CHAP_N", auth->a_mutual_user); 390 keys_add(response_keys, "CHAP_R", chap_r); 391 free(chap_r); 392 keys_save(response_keys, response); 393 keys_delete(response_keys); 394 } else { 395 log_debugx("initiator did not request target authentication"); 396 } 397 398 keys_delete(request_keys); 399 pdu_send(response); 400 pdu_delete(response); 401} 402 403static void 404login_chap(struct connection *conn, struct auth_group *ag) 405{ 406 const struct auth *auth; 407 struct chap *chap; 408 struct pdu *request; 409 410 /* 411 * Receive CHAP_A PDU. 412 */ 413 log_debugx("beginning CHAP authentication; waiting for CHAP_A"); 414 request = login_receive_chap_a(conn); 415 416 /* 417 * Generate the challenge. 418 */ 419 chap = chap_new(); 420 421 /* 422 * Send the challenge. 423 */ 424 log_debugx("sending CHAP_C, binary challenge size is %zd bytes", 425 sizeof(chap->chap_challenge)); 426 login_send_chap_c(request, chap); 427 pdu_delete(request); 428 429 /* 430 * Receive CHAP_N/CHAP_R PDU and authenticate. 431 */ 432 log_debugx("waiting for CHAP_N/CHAP_R"); 433 request = login_receive_chap_r(conn, ag, chap, &auth); 434 435 /* 436 * Yay, authentication succeeded! 437 */ 438 log_debugx("authentication succeeded for user \"%s\"; " 439 "transitioning to operational parameter negotiation", auth->a_user); 440 login_send_chap_success(request, auth); 441 pdu_delete(request); 442 443 /* 444 * Leave username and CHAP information for discovery(). 445 */ 446 conn->conn_user = auth->a_user; 447 conn->conn_chap = chap; 448} 449 450static void 451login_negotiate_key(struct pdu *request, const char *name, 452 const char *value, bool skipped_security, struct keys *response_keys) 453{ 454 int which; 455 size_t tmp; 456 struct connection *conn; 457 458 conn = request->pdu_connection; 459 460 if (strcmp(name, "InitiatorName") == 0) { 461 if (!skipped_security) 462 log_errx(1, "initiator resent InitiatorName"); 463 } else if (strcmp(name, "SessionType") == 0) { 464 if (!skipped_security) 465 log_errx(1, "initiator resent SessionType"); 466 } else if (strcmp(name, "TargetName") == 0) { 467 if (!skipped_security) 468 log_errx(1, "initiator resent TargetName"); 469 } else if (strcmp(name, "InitiatorAlias") == 0) { 470 if (conn->conn_initiator_alias != NULL) 471 free(conn->conn_initiator_alias); 472 conn->conn_initiator_alias = checked_strdup(value); 473 } else if (strcmp(value, "Irrelevant") == 0) { 474 /* Ignore. */ 475 } else if (strcmp(name, "HeaderDigest") == 0) { 476 /* 477 * We don't handle digests for discovery sessions. 478 */ 479 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) { 480 log_debugx("discovery session; digests disabled"); 481 keys_add(response_keys, name, "None"); 482 return; 483 } 484 485 which = login_list_prefers(value, "CRC32C", "None"); 486 switch (which) { 487 case 1: 488 log_debugx("initiator prefers CRC32C " 489 "for header digest; we'll use it"); 490 conn->conn_header_digest = CONN_DIGEST_CRC32C; 491 keys_add(response_keys, name, "CRC32C"); 492 break; 493 case 2: 494 log_debugx("initiator prefers not to do " 495 "header digest; we'll comply"); 496 keys_add(response_keys, name, "None"); 497 break; 498 default: 499 log_warnx("initiator sent unrecognized " 500 "HeaderDigest value \"%s\"; will use None", value); 501 keys_add(response_keys, name, "None"); 502 break; 503 } 504 } else if (strcmp(name, "DataDigest") == 0) { 505 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) { 506 log_debugx("discovery session; digests disabled"); 507 keys_add(response_keys, name, "None"); 508 return; 509 } 510 511 which = login_list_prefers(value, "CRC32C", "None"); 512 switch (which) { 513 case 1: 514 log_debugx("initiator prefers CRC32C " 515 "for data digest; we'll use it"); 516 conn->conn_data_digest = CONN_DIGEST_CRC32C; 517 keys_add(response_keys, name, "CRC32C"); 518 break; 519 case 2: 520 log_debugx("initiator prefers not to do " 521 "data digest; we'll comply"); 522 keys_add(response_keys, name, "None"); 523 break; 524 default: 525 log_warnx("initiator sent unrecognized " 526 "DataDigest value \"%s\"; will use None", value); 527 keys_add(response_keys, name, "None"); 528 break; 529 } 530 } else if (strcmp(name, "MaxConnections") == 0) { 531 keys_add(response_keys, name, "1"); 532 } else if (strcmp(name, "InitialR2T") == 0) { 533 keys_add(response_keys, name, "Yes"); 534 } else if (strcmp(name, "ImmediateData") == 0) { 535 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) { 536 log_debugx("discovery session; ImmediateData irrelevant"); 537 keys_add(response_keys, name, "Irrelevant"); 538 } else { 539 if (strcmp(value, "Yes") == 0) { 540 conn->conn_immediate_data = true; 541 keys_add(response_keys, name, "Yes"); 542 } else { 543 conn->conn_immediate_data = false; 544 keys_add(response_keys, name, "No"); 545 } 546 } 547 } else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) { 548 tmp = strtoul(value, NULL, 10); 549 if (tmp <= 0) { 550 login_send_error(request, 0x02, 0x00); 551 log_errx(1, "received invalid " 552 "MaxRecvDataSegmentLength"); 553 } 554 555 /* 556 * MaxRecvDataSegmentLength is a direction-specific parameter. 557 * We'll limit our _send_ to what the initiator can handle but 558 * our MaxRecvDataSegmentLength is not influenced by the 559 * initiator in any way. 560 */ 561 if ((int)tmp > conn->conn_max_send_data_segment_limit) { 562 log_debugx("capping MaxRecvDataSegmentLength " 563 "from %zd to %d", tmp, 564 conn->conn_max_send_data_segment_limit); 565 tmp = conn->conn_max_send_data_segment_limit; 566 } 567 conn->conn_max_send_data_segment_length = tmp; 568 conn->conn_max_recv_data_segment_length = 569 conn->conn_max_recv_data_segment_limit; 570 keys_add_int(response_keys, name, 571 conn->conn_max_recv_data_segment_length); 572 } else if (strcmp(name, "MaxBurstLength") == 0) { 573 tmp = strtoul(value, NULL, 10); 574 if (tmp <= 0) { 575 login_send_error(request, 0x02, 0x00); 576 log_errx(1, "received invalid MaxBurstLength"); 577 } 578 if ((int)tmp > conn->conn_max_burst_limit) { 579 log_debugx("capping MaxBurstLength from %zd to %d", 580 tmp, conn->conn_max_burst_limit); 581 tmp = conn->conn_max_burst_limit; 582 } 583 conn->conn_max_burst_length = tmp; 584 keys_add_int(response_keys, name, tmp); 585 } else if (strcmp(name, "FirstBurstLength") == 0) { 586 tmp = strtoul(value, NULL, 10); 587 if (tmp <= 0) { 588 login_send_error(request, 0x02, 0x00); 589 log_errx(1, "received invalid FirstBurstLength"); 590 } 591 if ((int)tmp > conn->conn_first_burst_limit) { 592 log_debugx("capping FirstBurstLength from %zd to %d", 593 tmp, conn->conn_first_burst_limit); 594 tmp = conn->conn_first_burst_limit; 595 } 596 conn->conn_first_burst_length = tmp; 597 keys_add_int(response_keys, name, tmp); 598 } else if (strcmp(name, "DefaultTime2Wait") == 0) { 599 keys_add(response_keys, name, value); 600 } else if (strcmp(name, "DefaultTime2Retain") == 0) { 601 keys_add(response_keys, name, "0"); 602 } else if (strcmp(name, "MaxOutstandingR2T") == 0) { 603 keys_add(response_keys, name, "1"); 604 } else if (strcmp(name, "DataPDUInOrder") == 0) { 605 keys_add(response_keys, name, "Yes"); 606 } else if (strcmp(name, "DataSequenceInOrder") == 0) { 607 keys_add(response_keys, name, "Yes"); 608 } else if (strcmp(name, "ErrorRecoveryLevel") == 0) { 609 keys_add(response_keys, name, "0"); 610 } else if (strcmp(name, "OFMarker") == 0) { 611 keys_add(response_keys, name, "No"); 612 } else if (strcmp(name, "IFMarker") == 0) { 613 keys_add(response_keys, name, "No"); 614 } else if (strcmp(name, "iSCSIProtocolLevel") == 0) { 615 tmp = strtoul(value, NULL, 10); 616 if (tmp > 2) 617 tmp = 2; 618 keys_add_int(response_keys, name, tmp); 619 } else { 620 log_debugx("unknown key \"%s\"; responding " 621 "with NotUnderstood", name); 622 keys_add(response_keys, name, "NotUnderstood"); 623 } 624} 625 626static void 627login_redirect(struct pdu *request, const char *target_address) 628{ 629 struct pdu *response; 630 struct iscsi_bhs_login_response *bhslr2; 631 struct keys *response_keys; 632 633 response = login_new_response(request); 634 login_set_csg(response, login_csg(request)); 635 bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs; 636 bhslr2->bhslr_status_class = 0x01; 637 bhslr2->bhslr_status_detail = 0x01; 638 639 response_keys = keys_new(); 640 keys_add(response_keys, "TargetAddress", target_address); 641 642 keys_save(response_keys, response); 643 pdu_send(response); 644 pdu_delete(response); 645 keys_delete(response_keys); 646} 647 648static bool 649login_portal_redirect(struct connection *conn, struct pdu *request) 650{ 651 const struct portal_group *pg; 652 653 pg = conn->conn_portal->p_portal_group; 654 if (pg->pg_redirection == NULL) 655 return (false); 656 657 log_debugx("portal-group \"%s\" configured to redirect to %s", 658 pg->pg_name, pg->pg_redirection); 659 login_redirect(request, pg->pg_redirection); 660 661 return (true); 662} 663 664static bool 665login_target_redirect(struct connection *conn, struct pdu *request) 666{ 667 const char *target_address; 668 669 assert(conn->conn_portal->p_portal_group->pg_redirection == NULL); 670 671 if (conn->conn_target == NULL) 672 return (false); 673 674 target_address = conn->conn_target->t_redirection; 675 if (target_address == NULL) 676 return (false); 677 678 log_debugx("target \"%s\" configured to redirect to %s", 679 conn->conn_target->t_name, target_address); 680 login_redirect(request, target_address); 681 682 return (true); 683} 684 685static void 686login_negotiate(struct connection *conn, struct pdu *request) 687{ 688 struct pdu *response; 689 struct iscsi_bhs_login_response *bhslr2; 690 struct keys *request_keys, *response_keys; 691 int i; 692 bool redirected, skipped_security; 693 694 if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) { 695 /* 696 * Query the kernel for various size limits. In case of 697 * offload, it depends on hardware capabilities. 698 */ 699 assert(conn->conn_target != NULL); 700 conn->conn_max_recv_data_segment_limit = (1 << 24) - 1; 701 conn->conn_max_send_data_segment_limit = (1 << 24) - 1; 702 conn->conn_max_burst_limit = (1 << 24) - 1; 703 conn->conn_first_burst_limit = (1 << 24) - 1; 704 kernel_limits(conn->conn_portal->p_portal_group->pg_offload, 705 &conn->conn_max_recv_data_segment_limit, 706 &conn->conn_max_send_data_segment_limit, 707 &conn->conn_max_burst_limit, 708 &conn->conn_first_burst_limit); 709 710 /* We expect legal, usable values at this point. */ 711 assert(conn->conn_max_recv_data_segment_limit >= 512); 712 assert(conn->conn_max_recv_data_segment_limit < (1 << 24)); 713 assert(conn->conn_max_send_data_segment_limit >= 512); 714 assert(conn->conn_max_send_data_segment_limit < (1 << 24)); 715 assert(conn->conn_max_burst_limit >= 512); 716 assert(conn->conn_max_burst_limit < (1 << 24)); 717 assert(conn->conn_first_burst_limit >= 512); 718 assert(conn->conn_first_burst_limit < (1 << 24)); 719 assert(conn->conn_first_burst_limit <= 720 conn->conn_max_burst_limit); 721 722 /* 723 * Limit default send length in case it won't be negotiated. 724 * We can't do it for other limits, since they may affect both 725 * sender and receiver operation, and we must obey defaults. 726 */ 727 if (conn->conn_max_send_data_segment_limit < 728 conn->conn_max_send_data_segment_length) { 729 conn->conn_max_send_data_segment_length = 730 conn->conn_max_send_data_segment_limit; 731 } 732 } else { 733 conn->conn_max_recv_data_segment_limit = 734 MAX_DATA_SEGMENT_LENGTH; 735 conn->conn_max_send_data_segment_limit = 736 MAX_DATA_SEGMENT_LENGTH; 737 } 738 739 if (request == NULL) { 740 log_debugx("beginning operational parameter negotiation; " 741 "waiting for Login PDU"); 742 request = login_receive(conn, false); 743 skipped_security = false; 744 } else 745 skipped_security = true; 746 747 /* 748 * RFC 3720, 10.13.5. Status-Class and Status-Detail, says 749 * the redirection SHOULD be accepted by the initiator before 750 * authentication, but MUST be accepted afterwards; that's 751 * why we're doing it here and not earlier. 752 */ 753 redirected = login_target_redirect(conn, request); 754 if (redirected) { 755 log_debugx("initiator redirected; exiting"); 756 exit(0); 757 } 758 759 request_keys = keys_new(); 760 keys_load(request_keys, request); 761 762 response = login_new_response(request); 763 bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs; 764 bhslr2->bhslr_tsih = htons(0xbadd); 765 login_set_csg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 766 login_set_nsg(response, BHSLR_STAGE_FULL_FEATURE_PHASE); 767 response_keys = keys_new(); 768 769 if (skipped_security && 770 conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) { 771 if (conn->conn_target->t_alias != NULL) 772 keys_add(response_keys, 773 "TargetAlias", conn->conn_target->t_alias); 774 keys_add_int(response_keys, "TargetPortalGroupTag", 775 conn->conn_portal->p_portal_group->pg_tag); 776 } 777 778 for (i = 0; i < KEYS_MAX; i++) { 779 if (request_keys->keys_names[i] == NULL) 780 break; 781 782 login_negotiate_key(request, request_keys->keys_names[i], 783 request_keys->keys_values[i], skipped_security, 784 response_keys); 785 } 786 787 /* 788 * We'd started with usable values at our end. But a bad initiator 789 * could have presented a large FirstBurstLength and then a smaller 790 * MaxBurstLength (in that order) and because we process the key/value 791 * pairs in the order they are in the request we might have ended up 792 * with illegal values here. 793 */ 794 if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL && 795 conn->conn_first_burst_length > conn->conn_max_burst_length) { 796 log_errx(1, "initiator sent FirstBurstLength > MaxBurstLength"); 797 } 798 799 log_debugx("operational parameter negotiation done; " 800 "transitioning to Full Feature Phase"); 801 802 keys_save(response_keys, response); 803 pdu_send(response); 804 pdu_delete(response); 805 keys_delete(response_keys); 806 pdu_delete(request); 807 keys_delete(request_keys); 808} 809 810static void 811login_wait_transition(struct connection *conn) 812{ 813 struct pdu *request, *response; 814 struct iscsi_bhs_login_request *bhslr; 815 816 log_debugx("waiting for state transition request"); 817 request = login_receive(conn, false); 818 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 819 if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0) { 820 login_send_error(request, 0x02, 0x00); 821 log_errx(1, "got no \"T\" flag after answering AuthMethod"); 822 } 823 824 log_debugx("got state transition request"); 825 response = login_new_response(request); 826 pdu_delete(request); 827 login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 828 pdu_send(response); 829 pdu_delete(response); 830 831 login_negotiate(conn, NULL); 832} 833 834void 835login(struct connection *conn) 836{ 837 struct pdu *request, *response; 838 struct iscsi_bhs_login_request *bhslr; 839 struct keys *request_keys, *response_keys; 840 struct auth_group *ag; 841 struct portal_group *pg; 842 const char *initiator_name, *initiator_alias, *session_type, 843 *target_name, *auth_method; 844 bool redirected, fail, trans; 845 846 /* 847 * Handle the initial Login Request - figure out required authentication 848 * method and either transition to the next phase, if no authentication 849 * is required, or call appropriate authentication code. 850 */ 851 log_debugx("beginning Login Phase; waiting for Login PDU"); 852 request = login_receive(conn, true); 853 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 854 if (bhslr->bhslr_tsih != 0) { 855 login_send_error(request, 0x02, 0x0a); 856 log_errx(1, "received Login PDU with non-zero TSIH"); 857 } 858 859 pg = conn->conn_portal->p_portal_group; 860 861 memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid, 862 sizeof(conn->conn_initiator_isid)); 863 864 /* 865 * XXX: Implement the C flag some day. 866 */ 867 request_keys = keys_new(); 868 keys_load(request_keys, request); 869 870 assert(conn->conn_initiator_name == NULL); 871 initiator_name = keys_find(request_keys, "InitiatorName"); 872 if (initiator_name == NULL) { 873 login_send_error(request, 0x02, 0x07); 874 log_errx(1, "received Login PDU without InitiatorName"); 875 } 876 if (valid_iscsi_name(initiator_name) == false) { 877 login_send_error(request, 0x02, 0x00); 878 log_errx(1, "received Login PDU with invalid InitiatorName"); 879 } 880 conn->conn_initiator_name = checked_strdup(initiator_name); 881 log_set_peer_name(conn->conn_initiator_name); 882 setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name); 883 884 redirected = login_portal_redirect(conn, request); 885 if (redirected) { 886 log_debugx("initiator redirected; exiting"); 887 exit(0); 888 } 889 890 initiator_alias = keys_find(request_keys, "InitiatorAlias"); 891 if (initiator_alias != NULL) 892 conn->conn_initiator_alias = checked_strdup(initiator_alias); 893 894 assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE); 895 session_type = keys_find(request_keys, "SessionType"); 896 if (session_type != NULL) { 897 if (strcmp(session_type, "Normal") == 0) { 898 conn->conn_session_type = CONN_SESSION_TYPE_NORMAL; 899 } else if (strcmp(session_type, "Discovery") == 0) { 900 conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY; 901 } else { 902 login_send_error(request, 0x02, 0x00); 903 log_errx(1, "received Login PDU with invalid " 904 "SessionType \"%s\"", session_type); 905 } 906 } else 907 conn->conn_session_type = CONN_SESSION_TYPE_NORMAL; 908 909 assert(conn->conn_target == NULL); 910 if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) { 911 target_name = keys_find(request_keys, "TargetName"); 912 if (target_name == NULL) { 913 login_send_error(request, 0x02, 0x07); 914 log_errx(1, "received Login PDU without TargetName"); 915 } 916 917 conn->conn_port = port_find_in_pg(pg, target_name); 918 if (conn->conn_port == NULL) { 919 login_send_error(request, 0x02, 0x03); 920 log_errx(1, "requested target \"%s\" not found", 921 target_name); 922 } 923 conn->conn_target = conn->conn_port->p_target; 924 } 925 926 /* 927 * At this point we know what kind of authentication we need. 928 */ 929 if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) { 930 ag = conn->conn_port->p_auth_group; 931 if (ag == NULL) 932 ag = conn->conn_target->t_auth_group; 933 if (ag->ag_name != NULL) { 934 log_debugx("initiator requests to connect " 935 "to target \"%s\"; auth-group \"%s\"", 936 conn->conn_target->t_name, 937 ag->ag_name); 938 } else { 939 log_debugx("initiator requests to connect " 940 "to target \"%s\"", conn->conn_target->t_name); 941 } 942 } else { 943 assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY); 944 ag = pg->pg_discovery_auth_group; 945 if (ag->ag_name != NULL) { 946 log_debugx("initiator requests " 947 "discovery session; auth-group \"%s\"", ag->ag_name); 948 } else { 949 log_debugx("initiator requests discovery session"); 950 } 951 } 952 953 if (ag->ag_type == AG_TYPE_DENY) { 954 login_send_error(request, 0x02, 0x01); 955 log_errx(1, "auth-type is \"deny\""); 956 } 957 958 if (ag->ag_type == AG_TYPE_UNKNOWN) { 959 /* 960 * This can happen with empty auth-group. 961 */ 962 login_send_error(request, 0x02, 0x01); 963 log_errx(1, "auth-type not set, denying access"); 964 } 965 966 /* 967 * Enforce initiator-name and initiator-portal. 968 */ 969 if (auth_name_check(ag, initiator_name) != 0) { 970 login_send_error(request, 0x02, 0x02); 971 log_errx(1, "initiator does not match allowed initiator names"); 972 } 973 974 if (auth_portal_check(ag, &conn->conn_initiator_sa) != 0) { 975 login_send_error(request, 0x02, 0x02); 976 log_errx(1, "initiator does not match allowed " 977 "initiator portals"); 978 } 979 980 /* 981 * Let's see if the initiator intends to do any kind of authentication 982 * at all. 983 */ 984 if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) { 985 if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) { 986 login_send_error(request, 0x02, 0x01); 987 log_errx(1, "initiator skipped the authentication, " 988 "but authentication is required"); 989 } 990 991 keys_delete(request_keys); 992 993 log_debugx("initiator skipped the authentication, " 994 "and we don't need it; proceeding with negotiation"); 995 login_negotiate(conn, request); 996 return; 997 } 998 999 fail = false; 1000 response = login_new_response(request); 1001 response_keys = keys_new(); 1002 trans = (bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0; 1003 auth_method = keys_find(request_keys, "AuthMethod"); 1004 if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) { 1005 log_debugx("authentication not required"); 1006 if (auth_method == NULL || 1007 login_list_contains(auth_method, "None")) { 1008 keys_add(response_keys, "AuthMethod", "None"); 1009 } else { 1010 log_warnx("initiator requests " 1011 "AuthMethod \"%s\" instead of \"None\"", 1012 auth_method); 1013 keys_add(response_keys, "AuthMethod", "Reject"); 1014 } 1015 if (trans) 1016 login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 1017 } else { 1018 log_debugx("CHAP authentication required"); 1019 if (auth_method == NULL || 1020 login_list_contains(auth_method, "CHAP")) { 1021 keys_add(response_keys, "AuthMethod", "CHAP"); 1022 } else { 1023 log_warnx("initiator requests unsupported " 1024 "AuthMethod \"%s\" instead of \"CHAP\"", 1025 auth_method); 1026 keys_add(response_keys, "AuthMethod", "Reject"); 1027 fail = true; 1028 } 1029 } 1030 if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) { 1031 if (conn->conn_target->t_alias != NULL) 1032 keys_add(response_keys, 1033 "TargetAlias", conn->conn_target->t_alias); 1034 keys_add_int(response_keys, 1035 "TargetPortalGroupTag", pg->pg_tag); 1036 } 1037 keys_save(response_keys, response); 1038 1039 pdu_send(response); 1040 pdu_delete(response); 1041 keys_delete(response_keys); 1042 pdu_delete(request); 1043 keys_delete(request_keys); 1044 1045 if (fail) { 1046 log_debugx("sent reject for AuthMethod; exiting"); 1047 exit(1); 1048 } 1049 1050 if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) { 1051 login_chap(conn, ag); 1052 login_negotiate(conn, NULL); 1053 } else if (trans) { 1054 login_negotiate(conn, NULL); 1055 } else { 1056 login_wait_transition(conn); 1057 } 1058} 1059