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