1/*- 2 * Copyright (c) 2012 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Edward Tomasz Napierala under sponsorship 6 * from the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 */ 30 31#include <sys/cdefs.h> 32__FBSDID("$FreeBSD$"); 33 34#include <sys/types.h> 35#include <sys/ioctl.h> 36#include <assert.h> 37#include <stdbool.h> 38#include <stdio.h> 39#include <stdlib.h> 40#include <string.h> 41#include <netinet/in.h> 42 43#include "iscsid.h" 44#include "iscsi_proto.h" 45 46static int 47login_nsg(const struct pdu *response) 48{ 49 struct iscsi_bhs_login_response *bhslr; 50 51 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 52 53 return (bhslr->bhslr_flags & 0x03); 54} 55 56static void 57login_set_nsg(struct pdu *request, int nsg) 58{ 59 struct iscsi_bhs_login_request *bhslr; 60 61 assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION || 62 nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION || 63 nsg == BHSLR_STAGE_FULL_FEATURE_PHASE); 64 65 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 66 67 bhslr->bhslr_flags &= 0xFC; 68 bhslr->bhslr_flags |= nsg; 69} 70 71static void 72login_set_csg(struct pdu *request, int csg) 73{ 74 struct iscsi_bhs_login_request *bhslr; 75 76 assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION || 77 csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION || 78 csg == BHSLR_STAGE_FULL_FEATURE_PHASE); 79 80 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 81 82 bhslr->bhslr_flags &= 0xF3; 83 bhslr->bhslr_flags |= csg << 2; 84} 85 86static const char * 87login_target_error_str(int class, int detail) 88{ 89 static char msg[128]; 90 91 /* 92 * RFC 3270, 10.13.5. Status-Class and Status-Detail 93 */ 94 switch (class) { 95 case 0x01: 96 switch (detail) { 97 case 0x01: 98 return ("Target moved temporarily"); 99 case 0x02: 100 return ("Target moved permanently"); 101 default: 102 snprintf(msg, sizeof(msg), "unknown redirection; " 103 "Status-Class 0x%x, Status-Detail 0x%x", 104 class, detail); 105 return (msg); 106 } 107 case 0x02: 108 switch (detail) { 109 case 0x00: 110 return ("Initiator error"); 111 case 0x01: 112 return ("Authentication failure"); 113 case 0x02: 114 return ("Authorization failure"); 115 case 0x03: 116 return ("Not found"); 117 case 0x04: 118 return ("Target removed"); 119 case 0x05: 120 return ("Unsupported version"); 121 case 0x06: 122 return ("Too many connections"); 123 case 0x07: 124 return ("Missing parameter"); 125 case 0x08: 126 return ("Can't include in session"); 127 case 0x09: 128 return ("Session type not supported"); 129 case 0x0a: 130 return ("Session does not exist"); 131 case 0x0b: 132 return ("Invalid during login"); 133 default: 134 snprintf(msg, sizeof(msg), "unknown initiator error; " 135 "Status-Class 0x%x, Status-Detail 0x%x", 136 class, detail); 137 return (msg); 138 } 139 case 0x03: 140 switch (detail) { 141 case 0x00: 142 return ("Target error"); 143 case 0x01: 144 return ("Service unavailable"); 145 case 0x02: 146 return ("Out of resources"); 147 default: 148 snprintf(msg, sizeof(msg), "unknown target error; " 149 "Status-Class 0x%x, Status-Detail 0x%x", 150 class, detail); 151 return (msg); 152 } 153 default: 154 snprintf(msg, sizeof(msg), "unknown error; " 155 "Status-Class 0x%x, Status-Detail 0x%x", 156 class, detail); 157 return (msg); 158 } 159} 160 161static void 162kernel_modify(const struct connection *conn, const char *target_address) 163{ 164 struct iscsi_session_modify ism; 165 int error; 166 167 memset(&ism, 0, sizeof(ism)); 168 ism.ism_session_id = conn->conn_session_id; 169 memcpy(&ism.ism_conf, &conn->conn_conf, sizeof(ism.ism_conf)); 170 strlcpy(ism.ism_conf.isc_target_addr, target_address, 171 sizeof(ism.ism_conf.isc_target)); 172 error = ioctl(conn->conn_iscsi_fd, ISCSISMODIFY, &ism); 173 if (error != 0) { 174 log_err(1, "failed to redirect to %s: ISCSISMODIFY", 175 target_address); 176 } 177} 178 179/* 180 * XXX: The way it works is suboptimal; what should happen is described 181 * in draft-gilligan-iscsi-fault-tolerance-00. That, however, would 182 * be much more complicated: we would need to keep "dependencies" 183 * for sessions, so that, in case described in draft and using draft 184 * terminology, we would have three sessions: one for discovery, 185 * one for initial target portal, and one for redirect portal. 186 * This would allow us to "backtrack" on connection failure, 187 * as described in draft. 188 */ 189static void 190login_handle_redirection(struct connection *conn, struct pdu *response) 191{ 192 struct iscsi_bhs_login_response *bhslr; 193 struct keys *response_keys; 194 const char *target_address; 195 196 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 197 assert (bhslr->bhslr_status_class == 1); 198 199 response_keys = keys_new(); 200 keys_load(response_keys, response); 201 202 target_address = keys_find(response_keys, "TargetAddress"); 203 if (target_address == NULL) 204 log_errx(1, "received redirection without TargetAddress"); 205 if (target_address[0] == '\0') 206 log_errx(1, "received redirection with empty TargetAddress"); 207 if (strlen(target_address) >= 208 sizeof(conn->conn_conf.isc_target_addr) - 1) 209 log_errx(1, "received TargetAddress is too long"); 210 211 log_debugx("received redirection to \"%s\"", target_address); 212 kernel_modify(conn, target_address); 213 keys_delete(response_keys); 214} 215 216static struct pdu * 217login_receive(struct connection *conn) 218{ 219 struct pdu *response; 220 struct iscsi_bhs_login_response *bhslr; 221 const char *errorstr; 222 static bool initial = true; 223 224 response = pdu_new(conn); 225 pdu_receive(response); 226 if (response->pdu_bhs->bhs_opcode != ISCSI_BHS_OPCODE_LOGIN_RESPONSE) { 227 log_errx(1, "protocol error: received invalid opcode 0x%x", 228 response->pdu_bhs->bhs_opcode); 229 } 230 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 231 /* 232 * XXX: Implement the C flag some day. 233 */ 234 if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) 235 log_errx(1, "received Login PDU with unsupported \"C\" flag"); 236 if (bhslr->bhslr_version_max != 0x00) 237 log_errx(1, "received Login PDU with unsupported " 238 "Version-max 0x%x", bhslr->bhslr_version_max); 239 if (bhslr->bhslr_version_active != 0x00) 240 log_errx(1, "received Login PDU with unsupported " 241 "Version-active 0x%x", bhslr->bhslr_version_active); 242 if (bhslr->bhslr_status_class == 1) { 243 login_handle_redirection(conn, response); 244 log_debugx("redirection handled; exiting"); 245 exit(0); 246 } 247 if (bhslr->bhslr_status_class != 0) { 248 errorstr = login_target_error_str(bhslr->bhslr_status_class, 249 bhslr->bhslr_status_detail); 250 fail(conn, errorstr); 251 log_errx(1, "target returned error: %s", errorstr); 252 } 253 if (initial == false && 254 ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) { 255 /* 256 * It's a warning, not an error, to work around what seems 257 * to be bug in NetBSD iSCSI target. 258 */ 259 log_warnx("received Login PDU with wrong StatSN: " 260 "is %u, should be %u", ntohl(bhslr->bhslr_statsn), 261 conn->conn_statsn + 1); 262 } 263 conn->conn_tsih = ntohs(bhslr->bhslr_tsih); 264 conn->conn_statsn = ntohl(bhslr->bhslr_statsn); 265 266 initial = false; 267 268 return (response); 269} 270 271static struct pdu * 272login_new_request(struct connection *conn, int csg) 273{ 274 struct pdu *request; 275 struct iscsi_bhs_login_request *bhslr; 276 int nsg; 277 278 request = pdu_new(conn); 279 bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs; 280 bhslr->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_REQUEST | 281 ISCSI_BHS_OPCODE_IMMEDIATE; 282 283 bhslr->bhslr_flags = BHSLR_FLAGS_TRANSIT; 284 switch (csg) { 285 case BHSLR_STAGE_SECURITY_NEGOTIATION: 286 nsg = BHSLR_STAGE_OPERATIONAL_NEGOTIATION; 287 break; 288 case BHSLR_STAGE_OPERATIONAL_NEGOTIATION: 289 nsg = BHSLR_STAGE_FULL_FEATURE_PHASE; 290 break; 291 default: 292 assert(!"invalid csg"); 293 log_errx(1, "invalid csg %d", csg); 294 } 295 login_set_csg(request, csg); 296 login_set_nsg(request, nsg); 297 298 memcpy(bhslr->bhslr_isid, &conn->conn_isid, sizeof(bhslr->bhslr_isid)); 299 bhslr->bhslr_tsih = htons(conn->conn_tsih); 300 bhslr->bhslr_initiator_task_tag = 0; 301 bhslr->bhslr_cmdsn = 0; 302 bhslr->bhslr_expstatsn = htonl(conn->conn_statsn + 1); 303 304 return (request); 305} 306 307static int 308login_list_prefers(const char *list, 309 const char *choice1, const char *choice2) 310{ 311 char *tofree, *str, *token; 312 313 tofree = str = checked_strdup(list); 314 315 while ((token = strsep(&str, ",")) != NULL) { 316 if (strcmp(token, choice1) == 0) { 317 free(tofree); 318 return (1); 319 } 320 if (strcmp(token, choice2) == 0) { 321 free(tofree); 322 return (2); 323 } 324 } 325 free(tofree); 326 return (-1); 327} 328 329static void 330login_negotiate_key(struct connection *conn, const char *name, 331 const char *value) 332{ 333 int which, tmp; 334 335 if (strcmp(name, "TargetAlias") == 0) { 336 strlcpy(conn->conn_target_alias, value, 337 sizeof(conn->conn_target_alias)); 338 } else if (strcmp(value, "Irrelevant") == 0) { 339 /* Ignore. */ 340 } else if (strcmp(name, "HeaderDigest") == 0) { 341 which = login_list_prefers(value, "CRC32C", "None"); 342 switch (which) { 343 case 1: 344 log_debugx("target prefers CRC32C " 345 "for header digest; we'll use it"); 346 conn->conn_header_digest = CONN_DIGEST_CRC32C; 347 break; 348 case 2: 349 log_debugx("target prefers not to do " 350 "header digest; we'll comply"); 351 break; 352 default: 353 log_warnx("target sent unrecognized " 354 "HeaderDigest value \"%s\"; will use None", value); 355 break; 356 } 357 } else if (strcmp(name, "DataDigest") == 0) { 358 which = login_list_prefers(value, "CRC32C", "None"); 359 switch (which) { 360 case 1: 361 log_debugx("target prefers CRC32C " 362 "for data digest; we'll use it"); 363 conn->conn_data_digest = CONN_DIGEST_CRC32C; 364 break; 365 case 2: 366 log_debugx("target prefers not to do " 367 "data digest; we'll comply"); 368 break; 369 default: 370 log_warnx("target sent unrecognized " 371 "DataDigest value \"%s\"; will use None", value); 372 break; 373 } 374 } else if (strcmp(name, "MaxConnections") == 0) { 375 /* Ignore. */ 376 } else if (strcmp(name, "InitialR2T") == 0) { 377 if (strcmp(value, "Yes") == 0) 378 conn->conn_initial_r2t = true; 379 else 380 conn->conn_initial_r2t = false; 381 } else if (strcmp(name, "ImmediateData") == 0) { 382 if (strcmp(value, "Yes") == 0) 383 conn->conn_immediate_data = true; 384 else 385 conn->conn_immediate_data = false; 386 } else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) { 387 tmp = strtoul(value, NULL, 10); 388 if (tmp <= 0) 389 log_errx(1, "received invalid " 390 "MaxRecvDataSegmentLength"); 391 if (tmp > ISCSI_MAX_DATA_SEGMENT_LENGTH) { 392 log_debugx("capping MaxRecvDataSegmentLength " 393 "from %d to %d", tmp, ISCSI_MAX_DATA_SEGMENT_LENGTH); 394 tmp = ISCSI_MAX_DATA_SEGMENT_LENGTH; 395 } 396 conn->conn_max_data_segment_length = tmp; 397 } else if (strcmp(name, "MaxBurstLength") == 0) { 398 if (conn->conn_immediate_data) { 399 tmp = strtoul(value, NULL, 10); 400 if (tmp <= 0) 401 log_errx(1, "received invalid MaxBurstLength"); 402 conn->conn_max_burst_length = tmp; 403 } 404 } else if (strcmp(name, "FirstBurstLength") == 0) { 405 tmp = strtoul(value, NULL, 10); 406 if (tmp <= 0) 407 log_errx(1, "received invalid FirstBurstLength"); 408 conn->conn_first_burst_length = tmp; 409 } else if (strcmp(name, "DefaultTime2Wait") == 0) { 410 /* Ignore */ 411 } else if (strcmp(name, "DefaultTime2Retain") == 0) { 412 /* Ignore */ 413 } else if (strcmp(name, "MaxOutstandingR2T") == 0) { 414 /* Ignore */ 415 } else if (strcmp(name, "DataPDUInOrder") == 0) { 416 /* Ignore */ 417 } else if (strcmp(name, "DataSequenceInOrder") == 0) { 418 /* Ignore */ 419 } else if (strcmp(name, "ErrorRecoveryLevel") == 0) { 420 /* Ignore */ 421 } else if (strcmp(name, "OFMarker") == 0) { 422 /* Ignore */ 423 } else if (strcmp(name, "IFMarker") == 0) { 424 /* Ignore */ 425 } else if (strcmp(name, "TargetPortalGroupTag") == 0) { 426 /* Ignore */ 427 } else { 428 log_debugx("unknown key \"%s\"; ignoring", name); 429 } 430} 431 432static void 433login_negotiate(struct connection *conn) 434{ 435 struct pdu *request, *response; 436 struct keys *request_keys, *response_keys; 437 struct iscsi_bhs_login_response *bhslr; 438 int i, nrequests = 0; 439 440 log_debugx("beginning operational parameter negotiation"); 441 request = login_new_request(conn, BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 442 request_keys = keys_new(); 443 444 /* 445 * The following keys are irrelevant for discovery sessions. 446 */ 447 if (conn->conn_conf.isc_discovery == 0) { 448 if (conn->conn_conf.isc_header_digest != 0) 449 keys_add(request_keys, "HeaderDigest", "CRC32C"); 450 else 451 keys_add(request_keys, "HeaderDigest", "None"); 452 if (conn->conn_conf.isc_data_digest != 0) 453 keys_add(request_keys, "DataDigest", "CRC32C"); 454 else 455 keys_add(request_keys, "DataDigest", "None"); 456 457 keys_add(request_keys, "ImmediateData", "Yes"); 458 keys_add_int(request_keys, "MaxBurstLength", 459 2 * ISCSI_MAX_DATA_SEGMENT_LENGTH); 460 keys_add_int(request_keys, "FirstBurstLength", 461 ISCSI_MAX_DATA_SEGMENT_LENGTH); 462 keys_add(request_keys, "InitialR2T", "Yes"); 463 keys_add(request_keys, "MaxOutstandingR2T", "1"); 464 } else { 465 keys_add(request_keys, "HeaderDigest", "None"); 466 keys_add(request_keys, "DataDigest", "None"); 467 } 468 469 keys_add_int(request_keys, "MaxRecvDataSegmentLength", 470 ISCSI_MAX_DATA_SEGMENT_LENGTH); 471 keys_add(request_keys, "DefaultTime2Wait", "0"); 472 keys_add(request_keys, "DefaultTime2Retain", "0"); 473 keys_add(request_keys, "ErrorRecoveryLevel", "0"); 474 keys_save(request_keys, request); 475 keys_delete(request_keys); 476 request_keys = NULL; 477 pdu_send(request); 478 pdu_delete(request); 479 request = NULL; 480 481 response = login_receive(conn); 482 response_keys = keys_new(); 483 keys_load(response_keys, response); 484 for (i = 0; i < KEYS_MAX; i++) { 485 if (response_keys->keys_names[i] == NULL) 486 break; 487 488 login_negotiate_key(conn, 489 response_keys->keys_names[i], response_keys->keys_values[i]); 490 } 491 492 keys_delete(response_keys); 493 response_keys = NULL; 494 495 for (;;) { 496 bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs; 497 if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0) 498 break; 499 500 nrequests++; 501 if (nrequests > 5) { 502 log_warnx("received login response " 503 "without the \"T\" flag too many times; giving up"); 504 break; 505 } 506 507 log_debugx("received login response " 508 "without the \"T\" flag; sending another request"); 509 510 pdu_delete(response); 511 512 request = login_new_request(conn, 513 BHSLR_STAGE_OPERATIONAL_NEGOTIATION); 514 pdu_send(request); 515 pdu_delete(request); 516 517 response = login_receive(conn); 518 } 519 520 if (login_nsg(response) != BHSLR_STAGE_FULL_FEATURE_PHASE) 521 log_warnx("received final login response with wrong NSG 0x%x", 522 login_nsg(response)); 523 pdu_delete(response); 524 525 log_debugx("operational parameter negotiation done; " 526 "transitioning to Full Feature phase"); 527} 528 529static void 530login_send_chap_a(struct connection *conn) 531{ 532 struct pdu *request; 533 struct keys *request_keys; 534 535 request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION); 536 request_keys = keys_new(); 537 keys_add(request_keys, "CHAP_A", "5"); 538 keys_save(request_keys, request); 539 keys_delete(request_keys); 540 pdu_send(request); 541 pdu_delete(request); 542} 543 544static void 545login_send_chap_r(struct pdu *response) 546{ 547 struct connection *conn; 548 struct pdu *request; 549 struct keys *request_keys, *response_keys; 550 struct rchap *rchap; 551 const char *chap_a, *chap_c, *chap_i; 552 char *chap_r; 553 int error; 554 char *mutual_chap_c, *mutual_chap_i; 555 556 /* 557 * As in the rest of the initiator, 'request' means 558 * 'initiator -> target', and 'response' means 'target -> initiator', 559 * 560 * So, here the 'response' from the target is the packet that contains 561 * CHAP challenge; our CHAP response goes into 'request'. 562 */ 563 564 conn = response->pdu_connection; 565 566 response_keys = keys_new(); 567 keys_load(response_keys, response); 568 569 /* 570 * First, compute the response. 571 */ 572 chap_a = keys_find(response_keys, "CHAP_A"); 573 if (chap_a == NULL) 574 log_errx(1, "received CHAP packet without CHAP_A"); 575 chap_c = keys_find(response_keys, "CHAP_C"); 576 if (chap_c == NULL) 577 log_errx(1, "received CHAP packet without CHAP_C"); 578 chap_i = keys_find(response_keys, "CHAP_I"); 579 if (chap_i == NULL) 580 log_errx(1, "received CHAP packet without CHAP_I"); 581 582 if (strcmp(chap_a, "5") != 0) { 583 log_errx(1, "received CHAP packet " 584 "with unsupported CHAP_A \"%s\"", chap_a); 585 } 586 587 rchap = rchap_new(conn->conn_conf.isc_secret); 588 error = rchap_receive(rchap, chap_i, chap_c); 589 if (error != 0) { 590 log_errx(1, "received CHAP packet " 591 "with malformed CHAP_I or CHAP_C"); 592 } 593 chap_r = rchap_get_response(rchap); 594 rchap_delete(rchap); 595 596 keys_delete(response_keys); 597 598 request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION); 599 request_keys = keys_new(); 600 keys_add(request_keys, "CHAP_N", conn->conn_conf.isc_user); 601 keys_add(request_keys, "CHAP_R", chap_r); 602 free(chap_r); 603 604 /* 605 * If we want mutual authentication, we're expected to send 606 * our CHAP_I/CHAP_C now. 607 */ 608 if (conn->conn_conf.isc_mutual_user[0] != '\0') { 609 log_debugx("requesting mutual authentication; " 610 "binary challenge size is %zd bytes", 611 sizeof(conn->conn_mutual_chap->chap_challenge)); 612 613 assert(conn->conn_mutual_chap == NULL); 614 conn->conn_mutual_chap = chap_new(); 615 mutual_chap_i = chap_get_id(conn->conn_mutual_chap); 616 mutual_chap_c = chap_get_challenge(conn->conn_mutual_chap); 617 keys_add(request_keys, "CHAP_I", mutual_chap_i); 618 keys_add(request_keys, "CHAP_C", mutual_chap_c); 619 free(mutual_chap_i); 620 free(mutual_chap_c); 621 } 622 623 keys_save(request_keys, request); 624 keys_delete(request_keys); 625 pdu_send(request); 626 pdu_delete(request); 627} 628 629static void 630login_verify_mutual(const struct pdu *response) 631{ 632 struct connection *conn; 633 struct keys *response_keys; 634 const char *chap_n, *chap_r; 635 int error; 636 637 conn = response->pdu_connection; 638 639 response_keys = keys_new(); 640 keys_load(response_keys, response); 641 642 chap_n = keys_find(response_keys, "CHAP_N"); 643 if (chap_n == NULL) 644 log_errx(1, "received CHAP Response PDU without CHAP_N"); 645 chap_r = keys_find(response_keys, "CHAP_R"); 646 if (chap_r == NULL) 647 log_errx(1, "received CHAP Response PDU without CHAP_R"); 648 649 error = chap_receive(conn->conn_mutual_chap, chap_r); 650 if (error != 0) 651 log_errx(1, "received CHAP Response PDU with invalid CHAP_R"); 652 653 if (strcmp(chap_n, conn->conn_conf.isc_mutual_user) != 0) { 654 fail(conn, "Mutual CHAP failed"); 655 log_errx(1, "mutual CHAP authentication failed: wrong user"); 656 } 657 658 error = chap_authenticate(conn->conn_mutual_chap, 659 conn->conn_conf.isc_mutual_secret); 660 if (error != 0) { 661 fail(conn, "Mutual CHAP failed"); 662 log_errx(1, "mutual CHAP authentication failed: wrong secret"); 663 } 664 665 keys_delete(response_keys); 666 chap_delete(conn->conn_mutual_chap); 667 conn->conn_mutual_chap = NULL; 668 669 log_debugx("mutual CHAP authentication succeeded"); 670} 671 672static void 673login_chap(struct connection *conn) 674{ 675 struct pdu *response; 676 677 log_debugx("beginning CHAP authentication; sending CHAP_A"); 678 login_send_chap_a(conn); 679 680 log_debugx("waiting for CHAP_A/CHAP_C/CHAP_I"); 681 response = login_receive(conn); 682 683 log_debugx("sending CHAP_N/CHAP_R"); 684 login_send_chap_r(response); 685 pdu_delete(response); 686 687 /* 688 * XXX: Make sure this is not susceptible to MITM. 689 */ 690 691 log_debugx("waiting for CHAP result"); 692 response = login_receive(conn); 693 if (conn->conn_conf.isc_mutual_user[0] != '\0') 694 login_verify_mutual(response); 695 pdu_delete(response); 696 697 log_debugx("CHAP authentication done"); 698} 699 700void 701login(struct connection *conn) 702{ 703 struct pdu *request, *response; 704 struct keys *request_keys, *response_keys; 705 struct iscsi_bhs_login_response *bhslr2; 706 const char *auth_method; 707 int i; 708 709 log_debugx("beginning Login phase; sending Login PDU"); 710 request = login_new_request(conn, BHSLR_STAGE_SECURITY_NEGOTIATION); 711 request_keys = keys_new(); 712 if (conn->conn_conf.isc_mutual_user[0] != '\0') { 713 keys_add(request_keys, "AuthMethod", "CHAP"); 714 } else if (conn->conn_conf.isc_user[0] != '\0') { 715 /* 716 * Give target a chance to skip authentication if it 717 * doesn't feel like it. 718 * 719 * None is first, CHAP second; this is to work around 720 * what seems to be LIO (Linux target) bug: otherwise, 721 * if target is configured with no authentication, 722 * and we are configured to authenticate, the target 723 * will erroneously respond with AuthMethod=CHAP 724 * instead of AuthMethod=None, and will subsequently 725 * fail the connection. This usually happens with 726 * Discovery sessions, which default to no authentication. 727 */ 728 keys_add(request_keys, "AuthMethod", "None,CHAP"); 729 } else { 730 keys_add(request_keys, "AuthMethod", "None"); 731 } 732 keys_add(request_keys, "InitiatorName", 733 conn->conn_conf.isc_initiator); 734 if (conn->conn_conf.isc_initiator_alias[0] != '\0') { 735 keys_add(request_keys, "InitiatorAlias", 736 conn->conn_conf.isc_initiator_alias); 737 } 738 if (conn->conn_conf.isc_discovery == 0) { 739 keys_add(request_keys, "SessionType", "Normal"); 740 keys_add(request_keys, 741 "TargetName", conn->conn_conf.isc_target); 742 } else { 743 keys_add(request_keys, "SessionType", "Discovery"); 744 } 745 keys_save(request_keys, request); 746 keys_delete(request_keys); 747 pdu_send(request); 748 pdu_delete(request); 749 750 response = login_receive(conn); 751 752 response_keys = keys_new(); 753 keys_load(response_keys, response); 754 755 for (i = 0; i < KEYS_MAX; i++) { 756 if (response_keys->keys_names[i] == NULL) 757 break; 758 759 /* 760 * Not interested in AuthMethod at this point; we only need 761 * to parse things such as TargetAlias. 762 * 763 * XXX: This is somewhat ugly. We should have a way to apply 764 * all the keys to the session and use that by default 765 * instead of discarding them. 766 */ 767 if (strcmp(response_keys->keys_names[i], "AuthMethod") == 0) 768 continue; 769 770 login_negotiate_key(conn, 771 response_keys->keys_names[i], response_keys->keys_values[i]); 772 } 773 774 bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs; 775 if ((bhslr2->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0 && 776 login_nsg(response) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) { 777 if (conn->conn_conf.isc_mutual_user[0] != '\0') { 778 log_errx(1, "target requested transition " 779 "to operational parameter negotiation, " 780 "but we require mutual CHAP"); 781 } 782 783 log_debugx("target requested transition " 784 "to operational parameter negotiation"); 785 keys_delete(response_keys); 786 pdu_delete(response); 787 login_negotiate(conn); 788 return; 789 } 790 791 auth_method = keys_find(response_keys, "AuthMethod"); 792 if (auth_method == NULL) 793 log_errx(1, "received response without AuthMethod"); 794 if (strcmp(auth_method, "None") == 0) { 795 if (conn->conn_conf.isc_mutual_user[0] != '\0') { 796 log_errx(1, "target does not require authantication, " 797 "but we require mutual CHAP"); 798 } 799 800 log_debugx("target does not require authentication"); 801 keys_delete(response_keys); 802 pdu_delete(response); 803 login_negotiate(conn); 804 return; 805 } 806 807 if (strcmp(auth_method, "CHAP") != 0) { 808 fail(conn, "Unsupported AuthMethod"); 809 log_errx(1, "received response " 810 "with unsupported AuthMethod \"%s\"", auth_method); 811 } 812 813 if (conn->conn_conf.isc_user[0] == '\0' || 814 conn->conn_conf.isc_secret[0] == '\0') { 815 fail(conn, "Authentication required"); 816 log_errx(1, "target requests CHAP authentication, but we don't " 817 "have user and secret"); 818 } 819 820 keys_delete(response_keys); 821 response_keys = NULL; 822 pdu_delete(response); 823 response = NULL; 824 825 login_chap(conn); 826 login_negotiate(conn); 827} 828