drivers/target/iscsi/iscsi_target_nego.c

   1 /*******************************************************************************
   2  * This file contains main functions related to iSCSI Parameter negotiation.
   3  *
   4  * \u00a9 Copyright 2007-2011 RisingTide Systems LLC.
   5  *
   6  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   7  *
   8  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  ******************************************************************************/
  20
  21 #include <linux/ctype.h>
  22 #include <scsi/iscsi_proto.h>
  23 #include <target/target_core_base.h>
  24 #include <target/target_core_fabric.h>
  25 #include <target/iscsi/iscsi_transport.h>
  26
  27 #include "iscsi_target_core.h"
  28 #include "iscsi_target_parameters.h"
  29 #include "iscsi_target_login.h"
  30 #include "iscsi_target_nego.h"
  31 #include "iscsi_target_tpg.h"
  32 #include "iscsi_target_util.h"
  33 #include "iscsi_target.h"
  34 #include "iscsi_target_auth.h"
  35
  36 #define MAX_LOGIN_PDUS  7
  37 #define TEXT_LEN        4096
  38
  39 void convert_null_to_semi(char *buf, int len)
  40 {
  41         int i;
  42
  43         for (i = 0; i < len; i++)
  44                 if (buf[i] == '\0')
  45                         buf[i] = ';';
  46 }
  47
  48 static int strlen_semi(char *buf)
  49 {
  50         int i = 0;
  51
  52         while (buf[i] != '\0') {
  53                 if (buf[i] == ';')
  54                         return i;
  55                 i++;
  56         }
  57
  58         return -1;
  59 }
  60
  61 int extract_param(
  62         const char *in_buf,
  63         const char *pattern,
  64         unsigned int max_length,
  65         char *out_buf,
  66         unsigned char *type)
  67 {
  68         char *ptr;
  69         int len;
  70
  71         if (!in_buf || !pattern || !out_buf || !type)
  72                 return -1;
  73
  74         ptr = strstr(in_buf, pattern);
  75         if (!ptr)
  76                 return -1;
  77
  78         ptr = strstr(ptr, "=");
  79         if (!ptr)
  80                 return -1;
  81
  82         ptr += 1;
  83         if (*ptr == '0' && (*(ptr+1) == 'x' || *(ptr+1) == 'X')) {
  84                 ptr += 2; /* skip 0x */
  85                 *type = HEX;
  86         } else
  87                 *type = DECIMAL;
  88
  89         len = strlen_semi(ptr);
  90         if (len < 0)
  91                 return -1;
  92
  93         if (len > max_length) {
  94                 pr_err("Length of input: %d exceeds max_length:"
  95                         " %d\n", len, max_length);
  96                 return -1;
  97         }
  98         memcpy(out_buf, ptr, len);
  99         out_buf[len] = '\0';
 100
 101         return 0;
 102 }
 103
 104 static u32 iscsi_handle_authentication(
 105         struct iscsi_conn *conn,
 106         char *in_buf,
 107         char *out_buf,
 108         int in_length,
 109         int *out_length,
 110         unsigned char *authtype)
 111 {
 112         struct iscsi_session *sess = conn->sess;
 113         struct iscsi_node_auth *auth;
 114         struct iscsi_node_acl *iscsi_nacl;
 115         struct se_node_acl *se_nacl;
 116
 117         if (!sess->sess_ops->SessionType) {
 118                 /*
 119                  * For SessionType=Normal
 120                  */
 121                 se_nacl = conn->sess->se_sess->se_node_acl;
 122                 if (!se_nacl) {
 123                         pr_err("Unable to locate struct se_node_acl for"
 124                                         " CHAP auth\n");
 125                         return -1;
 126                 }
 127                 iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
 128                                 se_node_acl);
 129                 if (!iscsi_nacl) {
 130                         pr_err("Unable to locate struct iscsi_node_acl for"
 131                                         " CHAP auth\n");
 132                         return -1;
 133                 }
 134
 135                 auth = ISCSI_NODE_AUTH(iscsi_nacl);
 136         } else {
 137                 /*
 138                  * For SessionType=Discovery
 139                  */
 140                 auth = &iscsit_global->discovery_acl.node_auth;
 141         }
 142
 143         if (strstr("CHAP", authtype))
 144                 strcpy(conn->sess->auth_type, "CHAP");
 145         else
 146                 strcpy(conn->sess->auth_type, NONE);
 147
 148         if (strstr("None", authtype))
 149                 return 1;
 150 #ifdef CANSRP
 151         else if (strstr("SRP", authtype))
 152                 return srp_main_loop(conn, auth, in_buf, out_buf,
 153                                 &in_length, out_length);
 154 #endif
 155         else if (strstr("CHAP", authtype))
 156                 return chap_main_loop(conn, auth, in_buf, out_buf,
 157                                 &in_length, out_length);
 158         else if (strstr("SPKM1", authtype))
 159                 return 2;
 160         else if (strstr("SPKM2", authtype))
 161                 return 2;
 162         else if (strstr("KRB5", authtype))
 163                 return 2;
 164         else
 165                 return 2;
 166 }
 167
 168 static void iscsi_remove_failed_auth_entry(struct iscsi_conn *conn)
 169 {
 170         kfree(conn->auth_protocol);
 171 }
 172
 173 int iscsi_target_check_login_request(
 174         struct iscsi_conn *conn,
 175         struct iscsi_login *login)
 176 {
 177         int req_csg, req_nsg;
 178         u32 payload_length;
 179         struct iscsi_login_req *login_req;
 180
 181         login_req = (struct iscsi_login_req *) login->req;
 182         payload_length = ntoh24(login_req->dlength);
 183
 184         switch (login_req->opcode & ISCSI_OPCODE_MASK) {
 185         case ISCSI_OP_LOGIN:
 186                 break;
 187         default:
 188                 pr_err("Received unknown opcode 0x%02x.\n",
 189                                 login_req->opcode & ISCSI_OPCODE_MASK);
 190                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 191                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 192                 return -1;
 193         }
 194
 195         if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
 196             (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 197                 pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
 198                         " and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
 199                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 200                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 201                 return -1;
 202         }
 203
 204         req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
 205         req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);
 206
 207         if (req_csg != login->current_stage) {
 208                 pr_err("Initiator unexpectedly changed login stage"
 209                         " from %d to %d, login failed.\n", login->current_stage,
 210                         req_csg);
 211                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 212                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 213                 return -1;
 214         }
 215
 216         if ((req_nsg == 2) || (req_csg >= 2) ||
 217            ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
 218             (req_nsg <= req_csg))) {
 219                 pr_err("Illegal login_req->flags Combination, CSG: %d,"
 220                         " NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
 221                         req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
 222                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 223                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 224                 return -1;
 225         }
 226
 227         if ((login_req->max_version != login->version_max) ||
 228             (login_req->min_version != login->version_min)) {
 229                 pr_err("Login request changed Version Max/Nin"
 230                         " unexpectedly to 0x%02x/0x%02x, protocol error\n",
 231                         login_req->max_version, login_req->min_version);
 232                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 233                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 234                 return -1;
 235         }
 236
 237         if (memcmp(login_req->isid, login->isid, 6) != 0) {
 238                 pr_err("Login request changed ISID unexpectedly,"
 239                                 " protocol error.\n");
 240                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 241                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 242                 return -1;
 243         }
 244
 245         if (login_req->itt != login->init_task_tag) {
 246                 pr_err("Login request changed ITT unexpectedly to"
 247                         " 0x%08x, protocol error.\n", login_req->itt);
 248                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 249                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 250                 return -1;
 251         }
 252
 253         if (payload_length > MAX_KEY_VALUE_PAIRS) {
 254                 pr_err("Login request payload exceeds default"
 255                         " MaxRecvDataSegmentLength: %u, protocol error.\n",
 256                                 MAX_KEY_VALUE_PAIRS);
 257                 return -1;
 258         }
 259
 260         return 0;
 261 }
 262
 263 static int iscsi_target_check_first_request(
 264         struct iscsi_conn *conn,
 265         struct iscsi_login *login)
 266 {
 267         struct iscsi_param *param = NULL;
 268         struct se_node_acl *se_nacl;
 269
 270         login->first_request = 0;
 271
 272         list_for_each_entry(param, &conn->param_list->param_list, p_list) {
 273                 if (!strncmp(param->name, SESSIONTYPE, 11)) {
 274                         if (!IS_PSTATE_ACCEPTOR(param)) {
 275                                 pr_err("SessionType key not received"
 276                                         " in first login request.\n");
 277                                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 278                                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 279                                 return -1;
 280                         }
 281                         if (!strncmp(param->value, DISCOVERY, 9))
 282                                 return 0;
 283                 }
 284
 285                 if (!strncmp(param->name, INITIATORNAME, 13)) {
 286                         if (!IS_PSTATE_ACCEPTOR(param)) {
 287                                 if (!login->leading_connection)
 288                                         continue;
 289
 290                                 pr_err("InitiatorName key not received"
 291                                         " in first login request.\n");
 292                                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 293                                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 294                                 return -1;
 295                         }
 296
 297                         /*
 298                          * For non-leading connections, double check that the
 299                          * received InitiatorName matches the existing session's
 300                          * struct iscsi_node_acl.
 301                          */
 302                         if (!login->leading_connection) {
 303                                 se_nacl = conn->sess->se_sess->se_node_acl;
 304                                 if (!se_nacl) {
 305                                         pr_err("Unable to locate"
 306                                                 " struct se_node_acl\n");
 307                                         iscsit_tx_login_rsp(conn,
 308                                                         ISCSI_STATUS_CLS_INITIATOR_ERR,
 309                                                         ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
 310                                         return -1;
 311                                 }
 312
 313                                 if (strcmp(param->value,
 314                                                 se_nacl->initiatorname)) {
 315                                         pr_err("Incorrect"
 316                                                 " InitiatorName: %s for this"
 317                                                 " iSCSI Initiator Node.\n",
 318                                                 param->value);
 319                                         iscsit_tx_login_rsp(conn,
 320                                                         ISCSI_STATUS_CLS_INITIATOR_ERR,
 321                                                         ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
 322                                         return -1;
 323                                 }
 324                         }
 325                 }
 326         }
 327
 328         return 0;
 329 }
 330
 331 static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
 332 {
 333         u32 padding = 0;
 334         struct iscsi_session *sess = conn->sess;
 335         struct iscsi_login_rsp *login_rsp;
 336
 337         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 338
 339         login_rsp->opcode               = ISCSI_OP_LOGIN_RSP;
 340         hton24(login_rsp->dlength, login->rsp_length);
 341         memcpy(login_rsp->isid, login->isid, 6);
 342         login_rsp->tsih                 = cpu_to_be16(login->tsih);
 343         login_rsp->itt                  = login->init_task_tag;
 344         login_rsp->statsn               = cpu_to_be32(conn->stat_sn++);
 345         login_rsp->exp_cmdsn            = cpu_to_be32(conn->sess->exp_cmd_sn);
 346         login_rsp->max_cmdsn            = cpu_to_be32(conn->sess->max_cmd_sn);
 347
 348         pr_debug("Sending Login Response, Flags: 0x%02x, ITT: 0x%08x,"
 349                 " ExpCmdSN; 0x%08x, MaxCmdSN: 0x%08x, StatSN: 0x%08x, Length:"
 350                 " %u\n", login_rsp->flags, (__force u32)login_rsp->itt,
 351                 ntohl(login_rsp->exp_cmdsn), ntohl(login_rsp->max_cmdsn),
 352                 ntohl(login_rsp->statsn), login->rsp_length);
 353
 354         padding = ((-login->rsp_length) & 3);
 355
 356         if (conn->conn_transport->iscsit_put_login_tx(conn, login,
 357                                         login->rsp_length + padding) < 0)
 358                 return -1;
 359
 360         login->rsp_length               = 0;
 361         mutex_lock(&sess->cmdsn_mutex);
 362         login_rsp->exp_cmdsn            = cpu_to_be32(sess->exp_cmd_sn);
 363         login_rsp->max_cmdsn            = cpu_to_be32(sess->max_cmd_sn);
 364         mutex_unlock(&sess->cmdsn_mutex);
 365
 366         return 0;
 367 }
 368
 369 static int iscsi_target_do_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
 370 {
 371         if (iscsi_target_do_tx_login_io(conn, login) < 0)
 372                 return -1;
 373
 374         if (conn->conn_transport->iscsit_get_login_rx(conn, login) < 0)
 375                 return -1;
 376
 377         return 0;
 378 }
 379
 380 /*
 381  *      NOTE: We check for existing sessions or connections AFTER the initiator
 382  *      has been successfully authenticated in order to protect against faked
 383  *      ISID/TSIH combinations.
 384  */
 385 static int iscsi_target_check_for_existing_instances(
 386         struct iscsi_conn *conn,
 387         struct iscsi_login *login)
 388 {
 389         if (login->checked_for_existing)
 390                 return 0;
 391
 392         login->checked_for_existing = 1;
 393
 394         if (!login->tsih)
 395                 return iscsi_check_for_session_reinstatement(conn);
 396         else
 397                 return iscsi_login_post_auth_non_zero_tsih(conn, login->cid,
 398                                 login->initial_exp_statsn);
 399 }
 400
 401 static int iscsi_target_do_authentication(
 402         struct iscsi_conn *conn,
 403         struct iscsi_login *login)
 404 {
 405         int authret;
 406         u32 payload_length;
 407         struct iscsi_param *param;
 408         struct iscsi_login_req *login_req;
 409         struct iscsi_login_rsp *login_rsp;
 410
 411         login_req = (struct iscsi_login_req *) login->req;
 412         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 413         payload_length = ntoh24(login_req->dlength);
 414
 415         param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
 416         if (!param)
 417                 return -1;
 418
 419         authret = iscsi_handle_authentication(
 420                         conn,
 421                         login->req_buf,
 422                         login->rsp_buf,
 423                         payload_length,
 424                         &login->rsp_length,
 425                         param->value);
 426         switch (authret) {
 427         case 0:
 428                 pr_debug("Received OK response"
 429                 " from LIO Authentication, continuing.\n");
 430                 break;
 431         case 1:
 432                 pr_debug("iSCSI security negotiation"
 433                         " completed successfully.\n");
 434                 login->auth_complete = 1;
 435                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
 436                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 437                         login_rsp->flags |= (ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
 438                                              ISCSI_FLAG_LOGIN_TRANSIT);
 439                         login->current_stage = 1;
 440                 }
 441                 return iscsi_target_check_for_existing_instances(
 442                                 conn, login);
 443         case 2:
 444                 pr_err("Security negotiation"
 445                         " failed.\n");
 446                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 447                                 ISCSI_LOGIN_STATUS_AUTH_FAILED);
 448                 return -1;
 449         default:
 450                 pr_err("Received unknown error %d from LIO"
 451                                 " Authentication\n", authret);
 452                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 453                                 ISCSI_LOGIN_STATUS_TARGET_ERROR);
 454                 return -1;
 455         }
 456
 457         return 0;
 458 }
 459
 460 static int iscsi_target_handle_csg_zero(
 461         struct iscsi_conn *conn,
 462         struct iscsi_login *login)
 463 {
 464         int ret;
 465         u32 payload_length;
 466         struct iscsi_param *param;
 467         struct iscsi_login_req *login_req;
 468         struct iscsi_login_rsp *login_rsp;
 469
 470         login_req = (struct iscsi_login_req *) login->req;
 471         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 472         payload_length = ntoh24(login_req->dlength);
 473
 474         param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
 475         if (!param)
 476                 return -1;
 477
 478         ret = iscsi_decode_text_input(
 479                         PHASE_SECURITY|PHASE_DECLARATIVE,
 480                         SENDER_INITIATOR|SENDER_RECEIVER,
 481                         login->req_buf,
 482                         payload_length,
 483                         conn);
 484         if (ret < 0)
 485                 return -1;
 486
 487         if (ret > 0) {
 488                 if (login->auth_complete) {
 489                         pr_err("Initiator has already been"
 490                                 " successfully authenticated, but is still"
 491                                 " sending %s keys.\n", param->value);
 492                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 493                                         ISCSI_LOGIN_STATUS_INIT_ERR);
 494                         return -1;
 495                 }
 496
 497                 goto do_auth;
 498         }
 499
 500         if (login->first_request)
 501                 if (iscsi_target_check_first_request(conn, login) < 0)
 502                         return -1;
 503
 504         ret = iscsi_encode_text_output(
 505                         PHASE_SECURITY|PHASE_DECLARATIVE,
 506                         SENDER_TARGET,
 507                         login->rsp_buf,
 508                         &login->rsp_length,
 509                         conn->param_list);
 510         if (ret < 0)
 511                 return -1;
 512
 513         if (!iscsi_check_negotiated_keys(conn->param_list)) {
 514                 if (ISCSI_TPG_ATTRIB(ISCSI_TPG_C(conn))->authentication &&
 515                     !strncmp(param->value, NONE, 4)) {
 516                         pr_err("Initiator sent AuthMethod=None but"
 517                                 " Target is enforcing iSCSI Authentication,"
 518                                         " login failed.\n");
 519                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 520                                         ISCSI_LOGIN_STATUS_AUTH_FAILED);
 521                         return -1;
 522                 }
 523
 524                 if (ISCSI_TPG_ATTRIB(ISCSI_TPG_C(conn))->authentication &&
 525                     !login->auth_complete)
 526                         return 0;
 527
 528                 if (strncmp(param->value, NONE, 4) && !login->auth_complete)
 529                         return 0;
 530
 531                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
 532                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 533                         login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
 534                                             ISCSI_FLAG_LOGIN_TRANSIT;
 535                         login->current_stage = 1;
 536                 }
 537         }
 538
 539         return 0;
 540 do_auth:
 541         return iscsi_target_do_authentication(conn, login);
 542 }
 543
 544 static int iscsi_target_handle_csg_one(struct iscsi_conn *conn, struct iscsi_login *login)
 545 {
 546         int ret;
 547         u32 payload_length;
 548         struct iscsi_login_req *login_req;
 549         struct iscsi_login_rsp *login_rsp;
 550
 551         login_req = (struct iscsi_login_req *) login->req;
 552         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 553         payload_length = ntoh24(login_req->dlength);
 554
 555         ret = iscsi_decode_text_input(
 556                         PHASE_OPERATIONAL|PHASE_DECLARATIVE,
 557                         SENDER_INITIATOR|SENDER_RECEIVER,
 558                         login->req_buf,
 559                         payload_length,
 560                         conn);
 561         if (ret < 0) {
 562                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 563                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 564                 return -1;
 565         }
 566
 567         if (login->first_request)
 568                 if (iscsi_target_check_first_request(conn, login) < 0)
 569                         return -1;
 570
 571         if (iscsi_target_check_for_existing_instances(conn, login) < 0)
 572                 return -1;
 573
 574         ret = iscsi_encode_text_output(
 575                         PHASE_OPERATIONAL|PHASE_DECLARATIVE,
 576                         SENDER_TARGET,
 577                         login->rsp_buf,
 578                         &login->rsp_length,
 579                         conn->param_list);
 580         if (ret < 0) {
 581                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 582                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 583                 return -1;
 584         }
 585
 586         if (!login->auth_complete &&
 587              ISCSI_TPG_ATTRIB(ISCSI_TPG_C(conn))->authentication) {
 588                 pr_err("Initiator is requesting CSG: 1, has not been"
 589                          " successfully authenticated, and the Target is"
 590                         " enforcing iSCSI Authentication, login failed.\n");
 591                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 592                                 ISCSI_LOGIN_STATUS_AUTH_FAILED);
 593                 return -1;
 594         }
 595
 596         if (!iscsi_check_negotiated_keys(conn->param_list))
 597                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE3) &&
 598                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT))
 599                         login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE3 |
 600                                             ISCSI_FLAG_LOGIN_TRANSIT;
 601
 602         return 0;
 603 }
 604
 605 static int iscsi_target_do_login(struct iscsi_conn *conn, struct iscsi_login *login)
 606 {
 607         int pdu_count = 0;
 608         struct iscsi_login_req *login_req;
 609         struct iscsi_login_rsp *login_rsp;
 610
 611         login_req = (struct iscsi_login_req *) login->req;
 612         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 613
 614         while (1) {
 615                 if (++pdu_count > MAX_LOGIN_PDUS) {
 616                         pr_err("MAX_LOGIN_PDUS count reached.\n");
 617                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 618                                         ISCSI_LOGIN_STATUS_TARGET_ERROR);
 619                         return -1;
 620                 }
 621
 622                 switch (ISCSI_LOGIN_CURRENT_STAGE(login_req->flags)) {
 623                 case 0:
 624                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK;
 625                         if (iscsi_target_handle_csg_zero(conn, login) < 0)
 626                                 return -1;
 627                         break;
 628                 case 1:
 629                         login_rsp->flags |= ISCSI_FLAG_LOGIN_CURRENT_STAGE1;
 630                         if (iscsi_target_handle_csg_one(conn, login) < 0)
 631                                 return -1;
 632                         if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
 633                                 login->tsih = conn->sess->tsih;
 634                                 login->login_complete = 1;
 635                                 if (iscsi_target_do_tx_login_io(conn,
 636                                                 login) < 0)
 637                                         return -1;
 638                                 return 0;
 639                         }
 640                         break;
 641                 default:
 642                         pr_err("Illegal CSG: %d received from"
 643                                 " Initiator, protocol error.\n",
 644                                 ISCSI_LOGIN_CURRENT_STAGE(login_req->flags));
 645                         break;
 646                 }
 647
 648                 if (iscsi_target_do_login_io(conn, login) < 0)
 649                         return -1;
 650
 651                 if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
 652                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_TRANSIT;
 653                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
 654                 }
 655         }
 656
 657         return 0;
 658 }
 659
 660 static void iscsi_initiatorname_tolower(
 661         char *param_buf)
 662 {
 663         char *c;
 664         u32 iqn_size = strlen(param_buf), i;
 665
 666         for (i = 0; i < iqn_size; i++) {
 667                 c = &param_buf[i];
 668                 if (!isupper(*c))
 669                         continue;
 670
 671                 *c = tolower(*c);
 672         }
 673 }
 674
 675 /*
 676  * Processes the first Login Request..
 677  */
 678 int iscsi_target_locate_portal(
 679         struct iscsi_np *np,
 680         struct iscsi_conn *conn,
 681         struct iscsi_login *login)
 682 {
 683         char *i_buf = NULL, *s_buf = NULL, *t_buf = NULL;
 684         char *tmpbuf, *start = NULL, *end = NULL, *key, *value;
 685         struct iscsi_session *sess = conn->sess;
 686         struct iscsi_tiqn *tiqn;
 687         struct iscsi_login_req *login_req;
 688         u32 payload_length;
 689         int sessiontype = 0, ret = 0;
 690
 691         login_req = (struct iscsi_login_req *) login->req;
 692         payload_length = ntoh24(login_req->dlength);
 693
 694         tmpbuf = kzalloc(payload_length + 1, GFP_KERNEL);
 695         if (!tmpbuf) {
 696                 pr_err("Unable to allocate memory for tmpbuf.\n");
 697                 return -1;
 698         }
 699
 700         memcpy(tmpbuf, login->req_buf, payload_length);
 701         tmpbuf[payload_length] = '\0';
 702         start = tmpbuf;
 703         end = (start + payload_length);
 704
 705         /*
 706          * Locate the initial keys expected from the Initiator node in
 707          * the first login request in order to progress with the login phase.
 708          */
 709         while (start < end) {
 710                 if (iscsi_extract_key_value(start, &key, &value) < 0) {
 711                         ret = -1;
 712                         goto out;
 713                 }
 714
 715                 if (!strncmp(key, "InitiatorName", 13))
 716                         i_buf = value;
 717                 else if (!strncmp(key, "SessionType", 11))
 718                         s_buf = value;
 719                 else if (!strncmp(key, "TargetName", 10))
 720                         t_buf = value;
 721
 722                 start += strlen(key) + strlen(value) + 2;
 723         }
 724         /*
 725          * See 5.3.  Login Phase.
 726          */
 727         if (!i_buf) {
 728                 pr_err("InitiatorName key not received"
 729                         " in first login request.\n");
 730                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 731                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 732                 ret = -1;
 733                 goto out;
 734         }
 735         /*
 736          * Convert the incoming InitiatorName to lowercase following
 737          * RFC-3720 3.2.6.1. section c) that says that iSCSI IQNs
 738          * are NOT case sensitive.
 739          */
 740         iscsi_initiatorname_tolower(i_buf);
 741
 742         if (!s_buf) {
 743                 if (!login->leading_connection)
 744                         goto get_target;
 745
 746                 pr_err("SessionType key not received"
 747                         " in first login request.\n");
 748                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 749                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 750                 ret = -1;
 751                 goto out;
 752         }
 753
 754         /*
 755          * Use default portal group for discovery sessions.
 756          */
 757         sessiontype = strncmp(s_buf, DISCOVERY, 9);
 758         if (!sessiontype) {
 759                 conn->tpg = iscsit_global->discovery_tpg;
 760                 if (!login->leading_connection)
 761                         goto get_target;
 762
 763                 sess->sess_ops->SessionType = 1;
 764                 /*
 765                  * Setup crc32c modules from libcrypto
 766                  */
 767                 if (iscsi_login_setup_crypto(conn) < 0) {
 768                         pr_err("iscsi_login_setup_crypto() failed\n");
 769                         ret = -1;
 770                         goto out;
 771                 }
 772                 /*
 773                  * Serialize access across the discovery struct iscsi_portal_group to
 774                  * process login attempt.
 775                  */
 776                 if (iscsit_access_np(np, conn->tpg) < 0) {
 777                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 778                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
 779                         ret = -1;
 780                         goto out;
 781                 }
 782                 ret = 0;
 783                 goto out;
 784         }
 785
 786 get_target:
 787         if (!t_buf) {
 788                 pr_err("TargetName key not received"
 789                         " in first login request while"
 790                         " SessionType=Normal.\n");
 791                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 792                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 793                 ret = -1;
 794                 goto out;
 795         }
 796
 797         /*
 798          * Locate Target IQN from Storage Node.
 799          */
 800         tiqn = iscsit_get_tiqn_for_login(t_buf);
 801         if (!tiqn) {
 802                 pr_err("Unable to locate Target IQN: %s in"
 803                         " Storage Node\n", t_buf);
 804                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 805                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
 806                 ret = -1;
 807                 goto out;
 808         }
 809         pr_debug("Located Storage Object: %s\n", tiqn->tiqn);
 810
 811         /*
 812          * Locate Target Portal Group from Storage Node.
 813          */
 814         conn->tpg = iscsit_get_tpg_from_np(tiqn, np);
 815         if (!conn->tpg) {
 816                 pr_err("Unable to locate Target Portal Group"
 817                                 " on %s\n", tiqn->tiqn);
 818                 iscsit_put_tiqn_for_login(tiqn);
 819                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 820                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
 821                 ret = -1;
 822                 goto out;
 823         }
 824         pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
 825         /*
 826          * Setup crc32c modules from libcrypto
 827          */
 828         if (iscsi_login_setup_crypto(conn) < 0) {
 829                 pr_err("iscsi_login_setup_crypto() failed\n");
 830                 ret = -1;
 831                 goto out;
 832         }
 833         /*
 834          * Serialize access across the struct iscsi_portal_group to
 835          * process login attempt.
 836          */
 837         if (iscsit_access_np(np, conn->tpg) < 0) {
 838                 iscsit_put_tiqn_for_login(tiqn);
 839                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 840                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
 841                 ret = -1;
 842                 conn->tpg = NULL;
 843                 goto out;
 844         }
 845
 846         /*
 847          * conn->sess->node_acl will be set when the referenced
 848          * struct iscsi_session is located from received ISID+TSIH in
 849          * iscsi_login_non_zero_tsih_s2().
 850          */
 851         if (!login->leading_connection) {
 852                 ret = 0;
 853                 goto out;
 854         }
 855
 856         /*
 857          * This value is required in iscsi_login_zero_tsih_s2()
 858          */
 859         sess->sess_ops->SessionType = 0;
 860
 861         /*
 862          * Locate incoming Initiator IQN reference from Storage Node.
 863          */
 864         sess->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
 865                         &conn->tpg->tpg_se_tpg, i_buf);
 866         if (!sess->se_sess->se_node_acl) {
 867                 pr_err("iSCSI Initiator Node: %s is not authorized to"
 868                         " access iSCSI target portal group: %hu.\n",
 869                                 i_buf, conn->tpg->tpgt);
 870                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 871                                 ISCSI_LOGIN_STATUS_TGT_FORBIDDEN);
 872                 ret = -1;
 873                 goto out;
 874         }
 875
 876         ret = 0;
 877 out:
 878         kfree(tmpbuf);
 879         return ret;
 880 }
 881
 882 int iscsi_target_start_negotiation(
 883         struct iscsi_login *login,
 884         struct iscsi_conn *conn)
 885 {
 886         int ret;
 887
 888         ret = iscsi_target_do_login(conn, login);
 889         if (ret != 0)
 890                 iscsi_remove_failed_auth_entry(conn);
 891
 892         iscsi_target_nego_release(conn);
 893         return ret;
 894 }
 895
 896 void iscsi_target_nego_release(struct iscsi_conn *conn)
 897 {
 898         struct iscsi_login *login = conn->conn_login;
 899
 900         if (!login)
 901                 return;
 902
 903         kfree(login->req_buf);
 904         kfree(login->rsp_buf);
 905         kfree(login);
 906
 907         conn->conn_login = NULL;
 908 }