usr.sbin/ctld/login.c

   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 <assert.h>
  35 #include <stdbool.h>
  36 #include <stdint.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <unistd.h>
  41 #include <netinet/in.h>
  42
  43 #include "ctld.h"
  44 #include "iscsi_proto.h"
  45
  46 static void login_send_error(struct pdu *request,
  47     char class, char detail);
  48
  49 static void
  50 login_set_nsg(struct pdu *response, int nsg)
  51 {
  52         struct iscsi_bhs_login_response *bhslr;
  53
  54         assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
  55             nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
  56             nsg == BHSLR_STAGE_FULL_FEATURE_PHASE);
  57
  58         bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
  59
  60         bhslr->bhslr_flags &= 0xFC;
  61         bhslr->bhslr_flags |= nsg;
  62         bhslr->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
  63 }
  64
  65 static int
  66 login_csg(const struct pdu *request)
  67 {
  68         struct iscsi_bhs_login_request *bhslr;
  69
  70         bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
  71
  72         return ((bhslr->bhslr_flags & 0x0C) >> 2);
  73 }
  74
  75 static void
  76 login_set_csg(struct pdu *response, int csg)
  77 {
  78         struct iscsi_bhs_login_response *bhslr;
  79
  80         assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
  81             csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
  82             csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
  83
  84         bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
  85
  86         bhslr->bhslr_flags &= 0xF3;
  87         bhslr->bhslr_flags |= csg << 2;
  88 }
  89
  90 static struct pdu *
  91 login_receive(struct connection *conn, bool initial)
  92 {
  93         struct pdu *request;
  94         struct iscsi_bhs_login_request *bhslr;
  95
  96         request = pdu_new(conn);
  97         pdu_receive(request);
  98         if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
  99             ISCSI_BHS_OPCODE_LOGIN_REQUEST) {
 100                 /*
 101                  * The first PDU in session is special - if we receive any PDU
 102                  * different than login request, we have to drop the connection
 103                  * without sending response ("A target receiving any PDU
 104                  * except a Login request before the Login Phase is started MUST
 105                  * immediately terminate the connection on which the PDU
 106                  * was received.")
 107                  */
 108                 if (initial == false)
 109                         login_send_error(request, 0x02, 0x0b);
 110                 log_errx(1, "protocol error: received invalid opcode 0x%x",
 111                     request->pdu_bhs->bhs_opcode);
 112         }
 113         bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
 114         /*
 115          * XXX: Implement the C flag some day.
 116          */
 117         if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) {
 118                 login_send_error(request, 0x03, 0x00);
 119                 log_errx(1, "received Login PDU with unsupported \"C\" flag");
 120         }
 121         if (bhslr->bhslr_version_max != 0x00) {
 122                 login_send_error(request, 0x02, 0x05);
 123                 log_errx(1, "received Login PDU with unsupported "
 124                     "Version-max 0x%x", bhslr->bhslr_version_max);
 125         }
 126         if (bhslr->bhslr_version_min != 0x00) {
 127                 login_send_error(request, 0x02, 0x05);
 128                 log_errx(1, "received Login PDU with unsupported "
 129                     "Version-min 0x%x", bhslr->bhslr_version_min);
 130         }
 131         if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
 132                 login_send_error(request, 0x02, 0x05);
 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, 0x05);
 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
 149 static struct pdu *
 150 login_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
 174 static void
 175 login_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
 191 static int
 192 login_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
 208 static int
 209 login_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
 230 static struct pdu *
 231 login_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
 256 static void
 257 login_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
 279 static struct pdu *
 280 login_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
 337 static void
 338 login_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
 403 static void
 404 login_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 Negotiation Phase", 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
 450 static void
 451 login_negotiate_key(struct pdu *request, const char *name,
 452     const char *value, bool skipped_security, struct keys *response_keys)
 453 {
 454         int which, tmp;
 455         struct connection *conn;
 456
 457         conn = request->pdu_connection;
 458
 459         if (strcmp(name, "InitiatorName") == 0) {
 460                 if (!skipped_security)
 461                         log_errx(1, "initiator resent InitiatorName");
 462         } else if (strcmp(name, "SessionType") == 0) {
 463                 if (!skipped_security)
 464                         log_errx(1, "initiator resent SessionType");
 465         } else if (strcmp(name, "TargetName") == 0) {
 466                 if (!skipped_security)
 467                         log_errx(1, "initiator resent TargetName");
 468         } else if (strcmp(name, "InitiatorAlias") == 0) {
 469                 if (conn->conn_initiator_alias != NULL)
 470                         free(conn->conn_initiator_alias);
 471                 conn->conn_initiator_alias = checked_strdup(value);
 472         } else if (strcmp(value, "Irrelevant") == 0) {
 473                 /* Ignore. */
 474         } else if (strcmp(name, "HeaderDigest") == 0) {
 475                 /*
 476                  * We don't handle digests for discovery sessions.
 477                  */
 478                 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
 479                         log_debugx("discovery session; digests disabled");
 480                         keys_add(response_keys, name, "None");
 481                         return;
 482                 }
 483
 484                 which = login_list_prefers(value, "CRC32C", "None");
 485                 switch (which) {
 486                 case 1:
 487                         log_debugx("initiator prefers CRC32C "
 488                             "for header digest; we'll use it");
 489                         conn->conn_header_digest = CONN_DIGEST_CRC32C;
 490                         keys_add(response_keys, name, "CRC32C");
 491                         break;
 492                 case 2:
 493                         log_debugx("initiator prefers not to do "
 494                             "header digest; we'll comply");
 495                         keys_add(response_keys, name, "None");
 496                         break;
 497                 default:
 498                         log_warnx("initiator sent unrecognized "
 499                             "HeaderDigest value \"%s\"; will use None", value);
 500                         keys_add(response_keys, name, "None");
 501                         break;
 502                 }
 503         } else if (strcmp(name, "DataDigest") == 0) {
 504                 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
 505                         log_debugx("discovery session; digests disabled");
 506                         keys_add(response_keys, name, "None");
 507                         return;
 508                 }
 509
 510                 which = login_list_prefers(value, "CRC32C", "None");
 511                 switch (which) {
 512                 case 1:
 513                         log_debugx("initiator prefers CRC32C "
 514                             "for data digest; we'll use it");
 515                         conn->conn_data_digest = CONN_DIGEST_CRC32C;
 516                         keys_add(response_keys, name, "CRC32C");
 517                         break;
 518                 case 2:
 519                         log_debugx("initiator prefers not to do "
 520                             "data digest; we'll comply");
 521                         keys_add(response_keys, name, "None");
 522                         break;
 523                 default:
 524                         log_warnx("initiator sent unrecognized "
 525                             "DataDigest value \"%s\"; will use None", value);
 526                         keys_add(response_keys, name, "None");
 527                         break;
 528                 }
 529         } else if (strcmp(name, "MaxConnections") == 0) {
 530                 keys_add(response_keys, name, "1");
 531         } else if (strcmp(name, "InitialR2T") == 0) {
 532                 keys_add(response_keys, name, "Yes");
 533         } else if (strcmp(name, "ImmediateData") == 0) {
 534                 if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
 535                         log_debugx("discovery session; ImmediateData irrelevant");
 536                         keys_add(response_keys, name, "Irrelevant");
 537                 } else {
 538                         if (strcmp(value, "Yes") == 0) {
 539                                 conn->conn_immediate_data = true;
 540                                 keys_add(response_keys, name, "Yes");
 541                         } else {
 542                                 conn->conn_immediate_data = false;
 543                                 keys_add(response_keys, name, "No");
 544                         }
 545                 }
 546         } else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
 547                 tmp = strtoul(value, NULL, 10);
 548                 if (tmp <= 0) {
 549                         login_send_error(request, 0x02, 0x00);
 550                         log_errx(1, "received invalid "
 551                             "MaxRecvDataSegmentLength");
 552                 }
 553                 if (tmp > MAX_DATA_SEGMENT_LENGTH) {
 554                         log_debugx("capping MaxRecvDataSegmentLength "
 555                             "from %d to %d", tmp, MAX_DATA_SEGMENT_LENGTH);
 556                         tmp = MAX_DATA_SEGMENT_LENGTH;
 557                 }
 558                 conn->conn_max_data_segment_length = tmp;
 559                 keys_add_int(response_keys, name, MAX_DATA_SEGMENT_LENGTH);
 560         } else if (strcmp(name, "MaxBurstLength") == 0) {
 561                 tmp = strtoul(value, NULL, 10);
 562                 if (tmp <= 0) {
 563                         login_send_error(request, 0x02, 0x00);
 564                         log_errx(1, "received invalid MaxBurstLength");
 565                 }
 566                 if (tmp > MAX_BURST_LENGTH) {
 567                         log_debugx("capping MaxBurstLength from %d to %d",
 568                             tmp, MAX_BURST_LENGTH);
 569                         tmp = MAX_BURST_LENGTH;
 570                 }
 571                 conn->conn_max_burst_length = tmp;
 572                 keys_add(response_keys, name, value);
 573         } else if (strcmp(name, "FirstBurstLength") == 0) {
 574                 tmp = strtoul(value, NULL, 10);
 575                 if (tmp <= 0) {
 576                         login_send_error(request, 0x02, 0x00);
 577                         log_errx(1, "received invalid "
 578                             "FirstBurstLength");
 579                 }
 580                 if (tmp > MAX_DATA_SEGMENT_LENGTH) {
 581                         log_debugx("capping FirstBurstLength from %d to %d",
 582                             tmp, MAX_DATA_SEGMENT_LENGTH);
 583                         tmp = MAX_DATA_SEGMENT_LENGTH;
 584                 }
 585                 /*
 586                  * We don't pass the value to the kernel; it only enforces
 587                  * hardcoded limit anyway.
 588                  */
 589                 keys_add_int(response_keys, name, tmp);
 590         } else if (strcmp(name, "DefaultTime2Wait") == 0) {
 591                 keys_add(response_keys, name, value);
 592         } else if (strcmp(name, "DefaultTime2Retain") == 0) {
 593                 keys_add(response_keys, name, "0");
 594         } else if (strcmp(name, "MaxOutstandingR2T") == 0) {
 595                 keys_add(response_keys, name, "1");
 596         } else if (strcmp(name, "DataPDUInOrder") == 0) {
 597                 keys_add(response_keys, name, "Yes");
 598         } else if (strcmp(name, "DataSequenceInOrder") == 0) {
 599                 keys_add(response_keys, name, "Yes");
 600         } else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
 601                 keys_add(response_keys, name, "0");
 602         } else if (strcmp(name, "OFMarker") == 0) {
 603                 keys_add(response_keys, name, "No");
 604         } else if (strcmp(name, "IFMarker") == 0) {
 605                 keys_add(response_keys, name, "No");
 606         } else {
 607                 log_debugx("unknown key \"%s\"; responding "
 608                     "with NotUnderstood", name);
 609                 keys_add(response_keys, name, "NotUnderstood");
 610         }
 611 }
 612
 613 static void
 614 login_redirect(struct pdu *request, const char *target_address)
 615 {
 616         struct pdu *response;
 617         struct iscsi_bhs_login_response *bhslr2;
 618         struct keys *response_keys;
 619
 620         response = login_new_response(request);
 621         login_set_csg(response, login_csg(request));
 622         bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
 623         bhslr2->bhslr_status_class = 0x01;
 624         bhslr2->bhslr_status_detail = 0x01;
 625
 626         response_keys = keys_new();
 627         keys_add(response_keys, "TargetAddress", target_address);
 628
 629         keys_save(response_keys, response);
 630         pdu_send(response);
 631         pdu_delete(response);
 632         keys_delete(response_keys);
 633 }
 634
 635 static bool
 636 login_portal_redirect(struct connection *conn, struct pdu *request)
 637 {
 638         const struct portal_group *pg;
 639
 640         pg = conn->conn_portal->p_portal_group;
 641         if (pg->pg_redirection == NULL)
 642                 return (false);
 643
 644         log_debugx("portal-group \"%s\" configured to redirect to %s",
 645             pg->pg_name, pg->pg_redirection);
 646         login_redirect(request, pg->pg_redirection);
 647
 648         return (true);
 649 }
 650
 651 static bool
 652 login_target_redirect(struct connection *conn, struct pdu *request)
 653 {
 654         const char *target_address;
 655
 656         assert(conn->conn_portal->p_portal_group->pg_redirection == NULL);
 657
 658         if (conn->conn_target == NULL)
 659                 return (false);
 660
 661         target_address = conn->conn_target->t_redirection;
 662         if (target_address == NULL)
 663                 return (false);
 664
 665         log_debugx("target \"%s\" configured to redirect to %s",
 666           conn->conn_target->t_name, target_address);
 667         login_redirect(request, target_address);
 668
 669         return (true);
 670 }
 671
 672 static void
 673 login_negotiate(struct connection *conn, struct pdu *request)
 674 {
 675         struct pdu *response;
 676         struct iscsi_bhs_login_response *bhslr2;
 677         struct keys *request_keys, *response_keys;
 678         int i;
 679         bool redirected, skipped_security;
 680
 681         if (request == NULL) {
 682                 log_debugx("beginning operational parameter negotiation; "
 683                     "waiting for Login PDU");
 684                 request = login_receive(conn, false);
 685                 skipped_security = false;
 686         } else
 687                 skipped_security = true;
 688
 689         /*
 690          * RFC 3720, 10.13.5.  Status-Class and Status-Detail, says
 691          * the redirection SHOULD be accepted by the initiator before
 692          * authentication, but MUST be be accepted afterwards; that's
 693          * why we're doing it here and not earlier.
 694          */
 695         redirected = login_target_redirect(conn, request);
 696         if (redirected) {
 697                 log_debugx("initiator redirected; exiting");
 698                 exit(0);
 699         }
 700
 701         request_keys = keys_new();
 702         keys_load(request_keys, request);
 703
 704         response = login_new_response(request);
 705         bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
 706         bhslr2->bhslr_tsih = htons(0xbadd);
 707         login_set_csg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
 708         login_set_nsg(response, BHSLR_STAGE_FULL_FEATURE_PHASE);
 709         response_keys = keys_new();
 710
 711         if (skipped_security &&
 712             conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
 713                 if (conn->conn_target->t_alias != NULL)
 714                         keys_add(response_keys,
 715                             "TargetAlias", conn->conn_target->t_alias);
 716                 keys_add_int(response_keys, "TargetPortalGroupTag",
 717                     conn->conn_portal->p_portal_group->pg_tag);
 718         }
 719
 720         for (i = 0; i < KEYS_MAX; i++) {
 721                 if (request_keys->keys_names[i] == NULL)
 722                         break;
 723
 724                 login_negotiate_key(request, request_keys->keys_names[i],
 725                     request_keys->keys_values[i], skipped_security,
 726                     response_keys);
 727         }
 728
 729         log_debugx("operational parameter negotiation done; "
 730             "transitioning to Full Feature Phase");
 731
 732         keys_save(response_keys, response);
 733         pdu_send(response);
 734         pdu_delete(response);
 735         keys_delete(response_keys);
 736         pdu_delete(request);
 737         keys_delete(request_keys);
 738 }
 739
 740 static void
 741 login_wait_transition(struct connection *conn)
 742 {
 743         struct pdu *request, *response;
 744         struct iscsi_bhs_login_request *bhslr;
 745
 746         log_debugx("waiting for state transition request");
 747         request = login_receive(conn, false);
 748         bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
 749         if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0) {
 750                 login_send_error(request, 0x02, 0x00);
 751                 log_errx(1, "got no \"T\" flag after answering AuthMethod");
 752         }
 753         pdu_delete(request);
 754
 755         log_debugx("got state transition request");
 756         response = login_new_response(request);
 757         login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
 758         pdu_send(response);
 759         pdu_delete(response);
 760
 761         login_negotiate(conn, NULL);
 762 }
 763
 764 void
 765 login(struct connection *conn)
 766 {
 767         struct pdu *request, *response;
 768         struct iscsi_bhs_login_request *bhslr;
 769         struct keys *request_keys, *response_keys;
 770         struct auth_group *ag;
 771         struct portal_group *pg;
 772         const char *initiator_name, *initiator_alias, *session_type,
 773             *target_name, *auth_method;
 774         bool redirected, fail, trans;
 775
 776         /*
 777          * Handle the initial Login Request - figure out required authentication
 778          * method and either transition to the next phase, if no authentication
 779          * is required, or call appropriate authentication code.
 780          */
 781         log_debugx("beginning Login Phase; waiting for Login PDU");
 782         request = login_receive(conn, true);
 783         bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
 784         if (bhslr->bhslr_tsih != 0) {
 785                 login_send_error(request, 0x02, 0x0a);
 786                 log_errx(1, "received Login PDU with non-zero TSIH");
 787         }
 788
 789         pg = conn->conn_portal->p_portal_group;
 790
 791         memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid,
 792             sizeof(conn->conn_initiator_isid));
 793
 794         /*
 795          * XXX: Implement the C flag some day.
 796          */
 797         request_keys = keys_new();
 798         keys_load(request_keys, request);
 799
 800         assert(conn->conn_initiator_name == NULL);
 801         initiator_name = keys_find(request_keys, "InitiatorName");
 802         if (initiator_name == NULL) {
 803                 login_send_error(request, 0x02, 0x07);
 804                 log_errx(1, "received Login PDU without InitiatorName");
 805         }
 806         if (valid_iscsi_name(initiator_name) == false) {
 807                 login_send_error(request, 0x02, 0x00);
 808                 log_errx(1, "received Login PDU with invalid InitiatorName");
 809         }
 810         conn->conn_initiator_name = checked_strdup(initiator_name);
 811         log_set_peer_name(conn->conn_initiator_name);
 812         setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name);
 813
 814         redirected = login_portal_redirect(conn, request);
 815         if (redirected) {
 816                 log_debugx("initiator redirected; exiting");
 817                 exit(0);
 818         }
 819
 820         initiator_alias = keys_find(request_keys, "InitiatorAlias");
 821         if (initiator_alias != NULL)
 822                 conn->conn_initiator_alias = checked_strdup(initiator_alias);
 823
 824         assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE);
 825         session_type = keys_find(request_keys, "SessionType");
 826         if (session_type != NULL) {
 827                 if (strcmp(session_type, "Normal") == 0) {
 828                         conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
 829                 } else if (strcmp(session_type, "Discovery") == 0) {
 830                         conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY;
 831                 } else {
 832                         login_send_error(request, 0x02, 0x00);
 833                         log_errx(1, "received Login PDU with invalid "
 834                             "SessionType \"%s\"", session_type);
 835                 }
 836         } else
 837                 conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
 838
 839         assert(conn->conn_target == NULL);
 840         if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
 841                 target_name = keys_find(request_keys, "TargetName");
 842                 if (target_name == NULL) {
 843                         login_send_error(request, 0x02, 0x07);
 844                         log_errx(1, "received Login PDU without TargetName");
 845                 }
 846
 847                 conn->conn_port = port_find_in_pg(pg, target_name);
 848                 if (conn->conn_port == NULL) {
 849                         login_send_error(request, 0x02, 0x03);
 850                         log_errx(1, "requested target \"%s\" not found",
 851                             target_name);
 852                 }
 853                 conn->conn_target = conn->conn_port->p_target;
 854         }
 855
 856         /*
 857          * At this point we know what kind of authentication we need.
 858          */
 859         if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
 860                 ag = conn->conn_port->p_auth_group;
 861                 if (ag == NULL)
 862                         ag = conn->conn_target->t_auth_group;
 863                 if (ag->ag_name != NULL) {
 864                         log_debugx("initiator requests to connect "
 865                             "to target \"%s\"; auth-group \"%s\"",
 866                             conn->conn_target->t_name,
 867                             ag->ag_name);
 868                 } else {
 869                         log_debugx("initiator requests to connect "
 870                             "to target \"%s\"", conn->conn_target->t_name);
 871                 }
 872         } else {
 873                 assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY);
 874                 ag = pg->pg_discovery_auth_group;
 875                 if (ag->ag_name != NULL) {
 876                         log_debugx("initiator requests "
 877                             "discovery session; auth-group \"%s\"", ag->ag_name);
 878                 } else {
 879                         log_debugx("initiator requests discovery session");
 880                 }
 881         }
 882
 883         if (ag->ag_type == AG_TYPE_DENY) {
 884                 login_send_error(request, 0x02, 0x01);
 885                 log_errx(1, "auth-type is \"deny\"");
 886         }
 887
 888         if (ag->ag_type == AG_TYPE_UNKNOWN) {
 889                 /*
 890                  * This can happen with empty auth-group.
 891                  */
 892                 login_send_error(request, 0x02, 0x01);
 893                 log_errx(1, "auth-type not set, denying access");
 894         }
 895
 896         /*
 897          * Enforce initiator-name and initiator-portal.
 898          */
 899         if (auth_name_check(ag, initiator_name) != 0) {
 900                 login_send_error(request, 0x02, 0x02);
 901                 log_errx(1, "initiator does not match allowed initiator names");
 902         }
 903
 904         if (auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
 905                 login_send_error(request, 0x02, 0x02);
 906                 log_errx(1, "initiator does not match allowed "
 907                     "initiator portals");
 908         }
 909
 910         /*
 911          * Let's see if the initiator intends to do any kind of authentication
 912          * at all.
 913          */
 914         if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
 915                 if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
 916                         login_send_error(request, 0x02, 0x01);
 917                         log_errx(1, "initiator skipped the authentication, "
 918                             "but authentication is required");
 919                 }
 920
 921                 keys_delete(request_keys);
 922
 923                 log_debugx("initiator skipped the authentication, "
 924                     "and we don't need it; proceeding with negotiation");
 925                 login_negotiate(conn, request);
 926                 return;
 927         }
 928
 929         fail = false;
 930         response = login_new_response(request);
 931         response_keys = keys_new();
 932         trans = (bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0;
 933         auth_method = keys_find(request_keys, "AuthMethod");
 934         if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) {
 935                 log_debugx("authentication not required");
 936                 if (auth_method == NULL ||
 937                     login_list_contains(auth_method, "None")) {
 938                         keys_add(response_keys, "AuthMethod", "None");
 939                 } else {
 940                         log_warnx("initiator requests "
 941                             "AuthMethod \"%s\" instead of \"None\"",
 942                             auth_method);
 943                         keys_add(response_keys, "AuthMethod", "Reject");
 944                 }
 945                 if (trans)
 946                         login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
 947         } else {
 948                 log_debugx("CHAP authentication required");
 949                 if (auth_method == NULL ||
 950                     login_list_contains(auth_method, "CHAP")) {
 951                         keys_add(response_keys, "AuthMethod", "CHAP");
 952                 } else {
 953                         log_warnx("initiator requests unsupported "
 954                             "AuthMethod \"%s\" instead of \"CHAP\"",
 955                             auth_method);
 956                         keys_add(response_keys, "AuthMethod", "Reject");
 957                         fail = true;
 958                 }
 959         }
 960         if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
 961                 if (conn->conn_target->t_alias != NULL)
 962                         keys_add(response_keys,
 963                             "TargetAlias", conn->conn_target->t_alias);
 964                 keys_add_int(response_keys,
 965                     "TargetPortalGroupTag", pg->pg_tag);
 966         }
 967         keys_save(response_keys, response);
 968
 969         pdu_send(response);
 970         pdu_delete(response);
 971         keys_delete(response_keys);
 972         pdu_delete(request);
 973         keys_delete(request_keys);
 974
 975         if (fail) {
 976                 log_debugx("sent reject for AuthMethod; exiting");
 977                 exit(1);
 978         }
 979
 980         if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
 981                 login_chap(conn, ag);
 982                 login_negotiate(conn, NULL);
 983         } else if (trans) {
 984                 login_negotiate(conn, NULL);
 985         } else {
 986                 login_wait_transition(conn);
 987         }
 988 }