drivers/target/iscsi/iscsi_target_nego.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*******************************************************************************
   3  * This file contains main functions related to iSCSI Parameter negotiation.
   4  *
   5  * (c) Copyright 2007-2013 Datera, Inc.
   6  *
   7  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
   8  *
   9  ******************************************************************************/
  10
  11 #include <linux/ctype.h>
  12 #include <linux/kthread.h>
  13 #include <linux/slab.h>
  14 #include <linux/sched/signal.h>
  15 #include <net/sock.h>
  16 #include <scsi/iscsi_proto.h>
  17 #include <target/target_core_base.h>
  18 #include <target/target_core_fabric.h>
  19 #include <target/iscsi/iscsi_transport.h>
  20
  21 #include <target/iscsi/iscsi_target_core.h>
  22 #include "iscsi_target_parameters.h"
  23 #include "iscsi_target_login.h"
  24 #include "iscsi_target_nego.h"
  25 #include "iscsi_target_tpg.h"
  26 #include "iscsi_target_util.h"
  27 #include "iscsi_target.h"
  28 #include "iscsi_target_auth.h"
  29
  30 #define MAX_LOGIN_PDUS  7
  31 #define TEXT_LEN        4096
  32
  33 void convert_null_to_semi(char *buf, int len)
  34 {
  35         int i;
  36
  37         for (i = 0; i < len; i++)
  38                 if (buf[i] == '\0')
  39                         buf[i] = ';';
  40 }
  41
  42 static int strlen_semi(char *buf)
  43 {
  44         int i = 0;
  45
  46         while (buf[i] != '\0') {
  47                 if (buf[i] == ';')
  48                         return i;
  49                 i++;
  50         }
  51
  52         return -1;
  53 }
  54
  55 int extract_param(
  56         const char *in_buf,
  57         const char *pattern,
  58         unsigned int max_length,
  59         char *out_buf,
  60         unsigned char *type)
  61 {
  62         char *ptr;
  63         int len;
  64
  65         if (!in_buf || !pattern || !out_buf || !type)
  66                 return -1;
  67
  68         ptr = strstr(in_buf, pattern);
  69         if (!ptr)
  70                 return -1;
  71
  72         ptr = strstr(ptr, "=");
  73         if (!ptr)
  74                 return -1;
  75
  76         ptr += 1;
  77         if (*ptr == '0' && (*(ptr+1) == 'x' || *(ptr+1) == 'X')) {
  78                 ptr += 2; /* skip 0x */
  79                 *type = HEX;
  80         } else
  81                 *type = DECIMAL;
  82
  83         len = strlen_semi(ptr);
  84         if (len < 0)
  85                 return -1;
  86
  87         if (len >= max_length) {
  88                 pr_err("Length of input: %d exceeds max_length:"
  89                         " %d\n", len, max_length);
  90                 return -1;
  91         }
  92         memcpy(out_buf, ptr, len);
  93         out_buf[len] = '\0';
  94
  95         return 0;
  96 }
  97
  98 static u32 iscsi_handle_authentication(
  99         struct iscsi_conn *conn,
 100         char *in_buf,
 101         char *out_buf,
 102         int in_length,
 103         int *out_length,
 104         unsigned char *authtype)
 105 {
 106         struct iscsi_session *sess = conn->sess;
 107         struct iscsi_node_auth *auth;
 108         struct iscsi_node_acl *iscsi_nacl;
 109         struct iscsi_portal_group *iscsi_tpg;
 110         struct se_node_acl *se_nacl;
 111
 112         if (!sess->sess_ops->SessionType) {
 113                 /*
 114                  * For SessionType=Normal
 115                  */
 116                 se_nacl = conn->sess->se_sess->se_node_acl;
 117                 if (!se_nacl) {
 118                         pr_err("Unable to locate struct se_node_acl for"
 119                                         " CHAP auth\n");
 120                         return -1;
 121                 }
 122                 iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
 123                                 se_node_acl);
 124                 if (!iscsi_nacl) {
 125                         pr_err("Unable to locate struct iscsi_node_acl for"
 126                                         " CHAP auth\n");
 127                         return -1;
 128                 }
 129
 130                 if (se_nacl->dynamic_node_acl) {
 131                         iscsi_tpg = container_of(se_nacl->se_tpg,
 132                                         struct iscsi_portal_group, tpg_se_tpg);
 133
 134                         auth = &iscsi_tpg->tpg_demo_auth;
 135                 } else {
 136                         iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
 137                                                   se_node_acl);
 138
 139                         auth = &iscsi_nacl->node_auth;
 140                 }
 141         } else {
 142                 /*
 143                  * For SessionType=Discovery
 144                  */
 145                 auth = &iscsit_global->discovery_acl.node_auth;
 146         }
 147
 148         if (strstr("CHAP", authtype))
 149                 strcpy(conn->sess->auth_type, "CHAP");
 150         else
 151                 strcpy(conn->sess->auth_type, NONE);
 152
 153         if (strstr("None", authtype))
 154                 return 1;
 155 #ifdef CANSRP
 156         else if (strstr("SRP", authtype))
 157                 return srp_main_loop(conn, auth, in_buf, out_buf,
 158                                 &in_length, out_length);
 159 #endif
 160         else if (strstr("CHAP", authtype))
 161                 return chap_main_loop(conn, auth, in_buf, out_buf,
 162                                 &in_length, out_length);
 163         else if (strstr("SPKM1", authtype))
 164                 return 2;
 165         else if (strstr("SPKM2", authtype))
 166                 return 2;
 167         else if (strstr("KRB5", authtype))
 168                 return 2;
 169         else
 170                 return 2;
 171 }
 172
 173 static void iscsi_remove_failed_auth_entry(struct iscsi_conn *conn)
 174 {
 175         kfree(conn->auth_protocol);
 176 }
 177
 178 int iscsi_target_check_login_request(
 179         struct iscsi_conn *conn,
 180         struct iscsi_login *login)
 181 {
 182         int req_csg, req_nsg;
 183         u32 payload_length;
 184         struct iscsi_login_req *login_req;
 185
 186         login_req = (struct iscsi_login_req *) login->req;
 187         payload_length = ntoh24(login_req->dlength);
 188
 189         switch (login_req->opcode & ISCSI_OPCODE_MASK) {
 190         case ISCSI_OP_LOGIN:
 191                 break;
 192         default:
 193                 pr_err("Received unknown opcode 0x%02x.\n",
 194                                 login_req->opcode & ISCSI_OPCODE_MASK);
 195                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 196                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 197                 return -1;
 198         }
 199
 200         if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
 201             (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 202                 pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
 203                         " and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
 204                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 205                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 206                 return -1;
 207         }
 208
 209         req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
 210         req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);
 211
 212         if (req_csg != login->current_stage) {
 213                 pr_err("Initiator unexpectedly changed login stage"
 214                         " from %d to %d, login failed.\n", login->current_stage,
 215                         req_csg);
 216                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 217                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 218                 return -1;
 219         }
 220
 221         if ((req_nsg == 2) || (req_csg >= 2) ||
 222            ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
 223             (req_nsg <= req_csg))) {
 224                 pr_err("Illegal login_req->flags Combination, CSG: %d,"
 225                         " NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
 226                         req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
 227                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 228                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 229                 return -1;
 230         }
 231
 232         if ((login_req->max_version != login->version_max) ||
 233             (login_req->min_version != login->version_min)) {
 234                 pr_err("Login request changed Version Max/Nin"
 235                         " unexpectedly to 0x%02x/0x%02x, protocol error\n",
 236                         login_req->max_version, login_req->min_version);
 237                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 238                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 239                 return -1;
 240         }
 241
 242         if (memcmp(login_req->isid, login->isid, 6) != 0) {
 243                 pr_err("Login request changed ISID unexpectedly,"
 244                                 " protocol error.\n");
 245                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 246                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 247                 return -1;
 248         }
 249
 250         if (login_req->itt != login->init_task_tag) {
 251                 pr_err("Login request changed ITT unexpectedly to"
 252                         " 0x%08x, protocol error.\n", login_req->itt);
 253                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 254                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 255                 return -1;
 256         }
 257
 258         if (payload_length > MAX_KEY_VALUE_PAIRS) {
 259                 pr_err("Login request payload exceeds default"
 260                         " MaxRecvDataSegmentLength: %u, protocol error.\n",
 261                                 MAX_KEY_VALUE_PAIRS);
 262                 return -1;
 263         }
 264
 265         return 0;
 266 }
 267 EXPORT_SYMBOL(iscsi_target_check_login_request);
 268
 269 static int iscsi_target_check_first_request(
 270         struct iscsi_conn *conn,
 271         struct iscsi_login *login)
 272 {
 273         struct iscsi_param *param = NULL;
 274         struct se_node_acl *se_nacl;
 275
 276         login->first_request = 0;
 277
 278         list_for_each_entry(param, &conn->param_list->param_list, p_list) {
 279                 if (!strncmp(param->name, SESSIONTYPE, 11)) {
 280                         if (!IS_PSTATE_ACCEPTOR(param)) {
 281                                 pr_err("SessionType key not received"
 282                                         " in first login request.\n");
 283                                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 284                                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 285                                 return -1;
 286                         }
 287                         if (!strncmp(param->value, DISCOVERY, 9))
 288                                 return 0;
 289                 }
 290
 291                 if (!strncmp(param->name, INITIATORNAME, 13)) {
 292                         if (!IS_PSTATE_ACCEPTOR(param)) {
 293                                 if (!login->leading_connection)
 294                                         continue;
 295
 296                                 pr_err("InitiatorName key not received"
 297                                         " in first login request.\n");
 298                                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 299                                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
 300                                 return -1;
 301                         }
 302
 303                         /*
 304                          * For non-leading connections, double check that the
 305                          * received InitiatorName matches the existing session's
 306                          * struct iscsi_node_acl.
 307                          */
 308                         if (!login->leading_connection) {
 309                                 se_nacl = conn->sess->se_sess->se_node_acl;
 310                                 if (!se_nacl) {
 311                                         pr_err("Unable to locate"
 312                                                 " struct se_node_acl\n");
 313                                         iscsit_tx_login_rsp(conn,
 314                                                         ISCSI_STATUS_CLS_INITIATOR_ERR,
 315                                                         ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
 316                                         return -1;
 317                                 }
 318
 319                                 if (strcmp(param->value,
 320                                                 se_nacl->initiatorname)) {
 321                                         pr_err("Incorrect"
 322                                                 " InitiatorName: %s for this"
 323                                                 " iSCSI Initiator Node.\n",
 324                                                 param->value);
 325                                         iscsit_tx_login_rsp(conn,
 326                                                         ISCSI_STATUS_CLS_INITIATOR_ERR,
 327                                                         ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
 328                                         return -1;
 329                                 }
 330                         }
 331                 }
 332         }
 333
 334         return 0;
 335 }
 336
 337 static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
 338 {
 339         u32 padding = 0;
 340         struct iscsi_login_rsp *login_rsp;
 341
 342         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 343
 344         login_rsp->opcode               = ISCSI_OP_LOGIN_RSP;
 345         hton24(login_rsp->dlength, login->rsp_length);
 346         memcpy(login_rsp->isid, login->isid, 6);
 347         login_rsp->tsih                 = cpu_to_be16(login->tsih);
 348         login_rsp->itt                  = login->init_task_tag;
 349         login_rsp->statsn               = cpu_to_be32(conn->stat_sn++);
 350         login_rsp->exp_cmdsn            = cpu_to_be32(conn->sess->exp_cmd_sn);
 351         login_rsp->max_cmdsn            = cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
 352
 353         pr_debug("Sending Login Response, Flags: 0x%02x, ITT: 0x%08x,"
 354                 " ExpCmdSN; 0x%08x, MaxCmdSN: 0x%08x, StatSN: 0x%08x, Length:"
 355                 " %u\n", login_rsp->flags, (__force u32)login_rsp->itt,
 356                 ntohl(login_rsp->exp_cmdsn), ntohl(login_rsp->max_cmdsn),
 357                 ntohl(login_rsp->statsn), login->rsp_length);
 358
 359         padding = ((-login->rsp_length) & 3);
 360         /*
 361          * Before sending the last login response containing the transition
 362          * bit for full-feature-phase, go ahead and start up TX/RX threads
 363          * now to avoid potential resource allocation failures after the
 364          * final login response has been sent.
 365          */
 366         if (login->login_complete) {
 367                 int rc = iscsit_start_kthreads(conn);
 368                 if (rc) {
 369                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 370                                             ISCSI_LOGIN_STATUS_NO_RESOURCES);
 371                         return -1;
 372                 }
 373         }
 374
 375         if (conn->conn_transport->iscsit_put_login_tx(conn, login,
 376                                         login->rsp_length + padding) < 0)
 377                 goto err;
 378
 379         login->rsp_length               = 0;
 380
 381         return 0;
 382
 383 err:
 384         if (login->login_complete) {
 385                 if (conn->rx_thread && conn->rx_thread_active) {
 386                         send_sig(SIGINT, conn->rx_thread, 1);
 387                         complete(&conn->rx_login_comp);
 388                         kthread_stop(conn->rx_thread);
 389                 }
 390                 if (conn->tx_thread && conn->tx_thread_active) {
 391                         send_sig(SIGINT, conn->tx_thread, 1);
 392                         kthread_stop(conn->tx_thread);
 393                 }
 394                 spin_lock(&iscsit_global->ts_bitmap_lock);
 395                 bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
 396                                       get_order(1));
 397                 spin_unlock(&iscsit_global->ts_bitmap_lock);
 398         }
 399         return -1;
 400 }
 401
 402 static void iscsi_target_sk_data_ready(struct sock *sk)
 403 {
 404         struct iscsi_conn *conn = sk->sk_user_data;
 405         bool rc;
 406
 407         pr_debug("Entering iscsi_target_sk_data_ready: conn: %p\n", conn);
 408
 409         write_lock_bh(&sk->sk_callback_lock);
 410         if (!sk->sk_user_data) {
 411                 write_unlock_bh(&sk->sk_callback_lock);
 412                 return;
 413         }
 414         if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
 415                 write_unlock_bh(&sk->sk_callback_lock);
 416                 pr_debug("Got LOGIN_FLAGS_READY=0, conn: %p >>>>\n", conn);
 417                 return;
 418         }
 419         if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
 420                 write_unlock_bh(&sk->sk_callback_lock);
 421                 pr_debug("Got LOGIN_FLAGS_CLOSED=1, conn: %p >>>>\n", conn);
 422                 return;
 423         }
 424         if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) {
 425                 write_unlock_bh(&sk->sk_callback_lock);
 426                 pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p >>>>\n", conn);
 427                 if (iscsi_target_sk_data_ready == conn->orig_data_ready)
 428                         return;
 429                 conn->orig_data_ready(sk);
 430                 return;
 431         }
 432
 433         rc = schedule_delayed_work(&conn->login_work, 0);
 434         if (!rc) {
 435                 pr_debug("iscsi_target_sk_data_ready, schedule_delayed_work"
 436                          " got false\n");
 437         }
 438         write_unlock_bh(&sk->sk_callback_lock);
 439 }
 440
 441 static void iscsi_target_sk_state_change(struct sock *);
 442
 443 static void iscsi_target_set_sock_callbacks(struct iscsi_conn *conn)
 444 {
 445         struct sock *sk;
 446
 447         if (!conn->sock)
 448                 return;
 449
 450         sk = conn->sock->sk;
 451         pr_debug("Entering iscsi_target_set_sock_callbacks: conn: %p\n", conn);
 452
 453         write_lock_bh(&sk->sk_callback_lock);
 454         sk->sk_user_data = conn;
 455         conn->orig_data_ready = sk->sk_data_ready;
 456         conn->orig_state_change = sk->sk_state_change;
 457         sk->sk_data_ready = iscsi_target_sk_data_ready;
 458         sk->sk_state_change = iscsi_target_sk_state_change;
 459         write_unlock_bh(&sk->sk_callback_lock);
 460
 461         sk->sk_sndtimeo = TA_LOGIN_TIMEOUT * HZ;
 462         sk->sk_rcvtimeo = TA_LOGIN_TIMEOUT * HZ;
 463 }
 464
 465 static void iscsi_target_restore_sock_callbacks(struct iscsi_conn *conn)
 466 {
 467         struct sock *sk;
 468
 469         if (!conn->sock)
 470                 return;
 471
 472         sk = conn->sock->sk;
 473         pr_debug("Entering iscsi_target_restore_sock_callbacks: conn: %p\n", conn);
 474
 475         write_lock_bh(&sk->sk_callback_lock);
 476         if (!sk->sk_user_data) {
 477                 write_unlock_bh(&sk->sk_callback_lock);
 478                 return;
 479         }
 480         sk->sk_user_data = NULL;
 481         sk->sk_data_ready = conn->orig_data_ready;
 482         sk->sk_state_change = conn->orig_state_change;
 483         write_unlock_bh(&sk->sk_callback_lock);
 484
 485         sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
 486         sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
 487 }
 488
 489 static int iscsi_target_do_login(struct iscsi_conn *, struct iscsi_login *);
 490
 491 static bool __iscsi_target_sk_check_close(struct sock *sk)
 492 {
 493         if (sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) {
 494                 pr_debug("__iscsi_target_sk_check_close: TCP_CLOSE_WAIT|TCP_CLOSE,"
 495                         "returning FALSE\n");
 496                 return true;
 497         }
 498         return false;
 499 }
 500
 501 static bool iscsi_target_sk_check_close(struct iscsi_conn *conn)
 502 {
 503         bool state = false;
 504
 505         if (conn->sock) {
 506                 struct sock *sk = conn->sock->sk;
 507
 508                 read_lock_bh(&sk->sk_callback_lock);
 509                 state = (__iscsi_target_sk_check_close(sk) ||
 510                          test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
 511                 read_unlock_bh(&sk->sk_callback_lock);
 512         }
 513         return state;
 514 }
 515
 516 static bool iscsi_target_sk_check_flag(struct iscsi_conn *conn, unsigned int flag)
 517 {
 518         bool state = false;
 519
 520         if (conn->sock) {
 521                 struct sock *sk = conn->sock->sk;
 522
 523                 read_lock_bh(&sk->sk_callback_lock);
 524                 state = test_bit(flag, &conn->login_flags);
 525                 read_unlock_bh(&sk->sk_callback_lock);
 526         }
 527         return state;
 528 }
 529
 530 static bool iscsi_target_sk_check_and_clear(struct iscsi_conn *conn, unsigned int flag)
 531 {
 532         bool state = false;
 533
 534         if (conn->sock) {
 535                 struct sock *sk = conn->sock->sk;
 536
 537                 write_lock_bh(&sk->sk_callback_lock);
 538                 state = (__iscsi_target_sk_check_close(sk) ||
 539                          test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
 540                 if (!state)
 541                         clear_bit(flag, &conn->login_flags);
 542                 write_unlock_bh(&sk->sk_callback_lock);
 543         }
 544         return state;
 545 }
 546
 547 static void iscsi_target_login_drop(struct iscsi_conn *conn, struct iscsi_login *login)
 548 {
 549         struct iscsi_np *np = login->np;
 550         bool zero_tsih = login->zero_tsih;
 551
 552         iscsi_remove_failed_auth_entry(conn);
 553         iscsi_target_nego_release(conn);
 554         iscsi_target_login_sess_out(conn, np, zero_tsih, true);
 555 }
 556
 557 struct conn_timeout {
 558         struct timer_list timer;
 559         struct iscsi_conn *conn;
 560 };
 561
 562 static void iscsi_target_login_timeout(struct timer_list *t)
 563 {
 564         struct conn_timeout *timeout = from_timer(timeout, t, timer);
 565         struct iscsi_conn *conn = timeout->conn;
 566
 567         pr_debug("Entering iscsi_target_login_timeout >>>>>>>>>>>>>>>>>>>\n");
 568
 569         if (conn->login_kworker) {
 570                 pr_debug("Sending SIGINT to conn->login_kworker %s/%d\n",
 571                          conn->login_kworker->comm, conn->login_kworker->pid);
 572                 send_sig(SIGINT, conn->login_kworker, 1);
 573         }
 574 }
 575
 576 static void iscsi_target_do_login_rx(struct work_struct *work)
 577 {
 578         struct iscsi_conn *conn = container_of(work,
 579                                 struct iscsi_conn, login_work.work);
 580         struct iscsi_login *login = conn->login;
 581         struct iscsi_np *np = login->np;
 582         struct iscsi_portal_group *tpg = conn->tpg;
 583         struct iscsi_tpg_np *tpg_np = conn->tpg_np;
 584         struct conn_timeout timeout;
 585         int rc, zero_tsih = login->zero_tsih;
 586         bool state;
 587
 588         pr_debug("entering iscsi_target_do_login_rx, conn: %p, %s:%d\n",
 589                         conn, current->comm, current->pid);
 590         /*
 591          * If iscsi_target_do_login_rx() has been invoked by ->sk_data_ready()
 592          * before initial PDU processing in iscsi_target_start_negotiation()
 593          * has completed, go ahead and retry until it's cleared.
 594          *
 595          * Otherwise if the TCP connection drops while this is occuring,
 596          * iscsi_target_start_negotiation() will detect the failure, call
 597          * cancel_delayed_work_sync(&conn->login_work), and cleanup the
 598          * remaining iscsi connection resources from iscsi_np process context.
 599          */
 600         if (iscsi_target_sk_check_flag(conn, LOGIN_FLAGS_INITIAL_PDU)) {
 601                 schedule_delayed_work(&conn->login_work, msecs_to_jiffies(10));
 602                 return;
 603         }
 604
 605         spin_lock(&tpg->tpg_state_lock);
 606         state = (tpg->tpg_state == TPG_STATE_ACTIVE);
 607         spin_unlock(&tpg->tpg_state_lock);
 608
 609         if (!state) {
 610                 pr_debug("iscsi_target_do_login_rx: tpg_state != TPG_STATE_ACTIVE\n");
 611                 goto err;
 612         }
 613
 614         if (iscsi_target_sk_check_close(conn)) {
 615                 pr_debug("iscsi_target_do_login_rx, TCP state CLOSE\n");
 616                 goto err;
 617         }
 618
 619         conn->login_kworker = current;
 620         allow_signal(SIGINT);
 621
 622         timeout.conn = conn;
 623         timer_setup_on_stack(&timeout.timer, iscsi_target_login_timeout, 0);
 624         mod_timer(&timeout.timer, jiffies + TA_LOGIN_TIMEOUT * HZ);
 625         pr_debug("Starting login timer for %s/%d\n", current->comm, current->pid);
 626
 627         rc = conn->conn_transport->iscsit_get_login_rx(conn, login);
 628         del_timer_sync(&timeout.timer);
 629         destroy_timer_on_stack(&timeout.timer);
 630         flush_signals(current);
 631         conn->login_kworker = NULL;
 632
 633         if (rc < 0)
 634                 goto err;
 635
 636         pr_debug("iscsi_target_do_login_rx after rx_login_io, %p, %s:%d\n",
 637                         conn, current->comm, current->pid);
 638
 639         rc = iscsi_target_do_login(conn, login);
 640         if (rc < 0) {
 641                 goto err;
 642         } else if (!rc) {
 643                 if (iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_READ_ACTIVE))
 644                         goto err;
 645         } else if (rc == 1) {
 646                 iscsi_target_nego_release(conn);
 647                 iscsi_post_login_handler(np, conn, zero_tsih);
 648                 iscsit_deaccess_np(np, tpg, tpg_np);
 649         }
 650         return;
 651
 652 err:
 653         iscsi_target_restore_sock_callbacks(conn);
 654         iscsi_target_login_drop(conn, login);
 655         iscsit_deaccess_np(np, tpg, tpg_np);
 656 }
 657
 658 static void iscsi_target_sk_state_change(struct sock *sk)
 659 {
 660         struct iscsi_conn *conn;
 661         void (*orig_state_change)(struct sock *);
 662         bool state;
 663
 664         pr_debug("Entering iscsi_target_sk_state_change\n");
 665
 666         write_lock_bh(&sk->sk_callback_lock);
 667         conn = sk->sk_user_data;
 668         if (!conn) {
 669                 write_unlock_bh(&sk->sk_callback_lock);
 670                 return;
 671         }
 672         orig_state_change = conn->orig_state_change;
 673
 674         if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
 675                 pr_debug("Got LOGIN_FLAGS_READY=0 sk_state_change conn: %p\n",
 676                          conn);
 677                 write_unlock_bh(&sk->sk_callback_lock);
 678                 orig_state_change(sk);
 679                 return;
 680         }
 681         state = __iscsi_target_sk_check_close(sk);
 682         pr_debug("__iscsi_target_sk_close_change: state: %d\n", state);
 683
 684         if (test_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) {
 685                 pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1 sk_state_change"
 686                          " conn: %p\n", conn);
 687                 if (state)
 688                         set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
 689                 write_unlock_bh(&sk->sk_callback_lock);
 690                 orig_state_change(sk);
 691                 return;
 692         }
 693         if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
 694                 pr_debug("Got LOGIN_FLAGS_CLOSED=1 sk_state_change conn: %p\n",
 695                          conn);
 696                 write_unlock_bh(&sk->sk_callback_lock);
 697                 orig_state_change(sk);
 698                 return;
 699         }
 700         /*
 701          * If the TCP connection has dropped, go ahead and set LOGIN_FLAGS_CLOSED,
 702          * but only queue conn->login_work -> iscsi_target_do_login_rx()
 703          * processing if LOGIN_FLAGS_INITIAL_PDU has already been cleared.
 704          *
 705          * When iscsi_target_do_login_rx() runs, iscsi_target_sk_check_close()
 706          * will detect the dropped TCP connection from delayed workqueue context.
 707          *
 708          * If LOGIN_FLAGS_INITIAL_PDU is still set, which means the initial
 709          * iscsi_target_start_negotiation() is running, iscsi_target_do_login()
 710          * via iscsi_target_sk_check_close() or iscsi_target_start_negotiation()
 711          * via iscsi_target_sk_check_and_clear() is responsible for detecting the
 712          * dropped TCP connection in iscsi_np process context, and cleaning up
 713          * the remaining iscsi connection resources.
 714          */
 715         if (state) {
 716                 pr_debug("iscsi_target_sk_state_change got failed state\n");
 717                 set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
 718                 state = test_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
 719                 write_unlock_bh(&sk->sk_callback_lock);
 720
 721                 orig_state_change(sk);
 722
 723                 if (!state)
 724                         schedule_delayed_work(&conn->login_work, 0);
 725                 return;
 726         }
 727         write_unlock_bh(&sk->sk_callback_lock);
 728
 729         orig_state_change(sk);
 730 }
 731
 732 /*
 733  *      NOTE: We check for existing sessions or connections AFTER the initiator
 734  *      has been successfully authenticated in order to protect against faked
 735  *      ISID/TSIH combinations.
 736  */
 737 static int iscsi_target_check_for_existing_instances(
 738         struct iscsi_conn *conn,
 739         struct iscsi_login *login)
 740 {
 741         if (login->checked_for_existing)
 742                 return 0;
 743
 744         login->checked_for_existing = 1;
 745
 746         if (!login->tsih)
 747                 return iscsi_check_for_session_reinstatement(conn);
 748         else
 749                 return iscsi_login_post_auth_non_zero_tsih(conn, login->cid,
 750                                 login->initial_exp_statsn);
 751 }
 752
 753 static int iscsi_target_do_authentication(
 754         struct iscsi_conn *conn,
 755         struct iscsi_login *login)
 756 {
 757         int authret;
 758         u32 payload_length;
 759         struct iscsi_param *param;
 760         struct iscsi_login_req *login_req;
 761         struct iscsi_login_rsp *login_rsp;
 762
 763         login_req = (struct iscsi_login_req *) login->req;
 764         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 765         payload_length = ntoh24(login_req->dlength);
 766
 767         param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
 768         if (!param)
 769                 return -1;
 770
 771         authret = iscsi_handle_authentication(
 772                         conn,
 773                         login->req_buf,
 774                         login->rsp_buf,
 775                         payload_length,
 776                         &login->rsp_length,
 777                         param->value);
 778         switch (authret) {
 779         case 0:
 780                 pr_debug("Received OK response"
 781                 " from LIO Authentication, continuing.\n");
 782                 break;
 783         case 1:
 784                 pr_debug("iSCSI security negotiation"
 785                         " completed successfully.\n");
 786                 login->auth_complete = 1;
 787                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
 788                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 789                         login_rsp->flags |= (ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
 790                                              ISCSI_FLAG_LOGIN_TRANSIT);
 791                         login->current_stage = 1;
 792                 }
 793                 return iscsi_target_check_for_existing_instances(
 794                                 conn, login);
 795         case 2:
 796                 pr_err("Security negotiation"
 797                         " failed.\n");
 798                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 799                                 ISCSI_LOGIN_STATUS_AUTH_FAILED);
 800                 return -1;
 801         default:
 802                 pr_err("Received unknown error %d from LIO"
 803                                 " Authentication\n", authret);
 804                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 805                                 ISCSI_LOGIN_STATUS_TARGET_ERROR);
 806                 return -1;
 807         }
 808
 809         return 0;
 810 }
 811
 812 static int iscsi_target_handle_csg_zero(
 813         struct iscsi_conn *conn,
 814         struct iscsi_login *login)
 815 {
 816         int ret;
 817         u32 payload_length;
 818         struct iscsi_param *param;
 819         struct iscsi_login_req *login_req;
 820         struct iscsi_login_rsp *login_rsp;
 821
 822         login_req = (struct iscsi_login_req *) login->req;
 823         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 824         payload_length = ntoh24(login_req->dlength);
 825
 826         param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
 827         if (!param)
 828                 return -1;
 829
 830         ret = iscsi_decode_text_input(
 831                         PHASE_SECURITY|PHASE_DECLARATIVE,
 832                         SENDER_INITIATOR|SENDER_RECEIVER,
 833                         login->req_buf,
 834                         payload_length,
 835                         conn);
 836         if (ret < 0)
 837                 return -1;
 838
 839         if (ret > 0) {
 840                 if (login->auth_complete) {
 841                         pr_err("Initiator has already been"
 842                                 " successfully authenticated, but is still"
 843                                 " sending %s keys.\n", param->value);
 844                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 845                                         ISCSI_LOGIN_STATUS_INIT_ERR);
 846                         return -1;
 847                 }
 848
 849                 goto do_auth;
 850         } else if (!payload_length) {
 851                 pr_err("Initiator sent zero length security payload,"
 852                        " login failed\n");
 853                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 854                                     ISCSI_LOGIN_STATUS_AUTH_FAILED);
 855                 return -1;
 856         }
 857
 858         if (login->first_request)
 859                 if (iscsi_target_check_first_request(conn, login) < 0)
 860                         return -1;
 861
 862         ret = iscsi_encode_text_output(
 863                         PHASE_SECURITY|PHASE_DECLARATIVE,
 864                         SENDER_TARGET,
 865                         login->rsp_buf,
 866                         &login->rsp_length,
 867                         conn->param_list,
 868                         conn->tpg->tpg_attrib.login_keys_workaround);
 869         if (ret < 0)
 870                 return -1;
 871
 872         if (!iscsi_check_negotiated_keys(conn->param_list)) {
 873                 if (conn->tpg->tpg_attrib.authentication &&
 874                     !strncmp(param->value, NONE, 4)) {
 875                         pr_err("Initiator sent AuthMethod=None but"
 876                                 " Target is enforcing iSCSI Authentication,"
 877                                         " login failed.\n");
 878                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 879                                         ISCSI_LOGIN_STATUS_AUTH_FAILED);
 880                         return -1;
 881                 }
 882
 883                 if (conn->tpg->tpg_attrib.authentication &&
 884                     !login->auth_complete)
 885                         return 0;
 886
 887                 if (strncmp(param->value, NONE, 4) && !login->auth_complete)
 888                         return 0;
 889
 890                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
 891                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
 892                         login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
 893                                             ISCSI_FLAG_LOGIN_TRANSIT;
 894                         login->current_stage = 1;
 895                 }
 896         }
 897
 898         return 0;
 899 do_auth:
 900         return iscsi_target_do_authentication(conn, login);
 901 }
 902
 903 static int iscsi_target_handle_csg_one(struct iscsi_conn *conn, struct iscsi_login *login)
 904 {
 905         int ret;
 906         u32 payload_length;
 907         struct iscsi_login_req *login_req;
 908         struct iscsi_login_rsp *login_rsp;
 909
 910         login_req = (struct iscsi_login_req *) login->req;
 911         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 912         payload_length = ntoh24(login_req->dlength);
 913
 914         ret = iscsi_decode_text_input(
 915                         PHASE_OPERATIONAL|PHASE_DECLARATIVE,
 916                         SENDER_INITIATOR|SENDER_RECEIVER,
 917                         login->req_buf,
 918                         payload_length,
 919                         conn);
 920         if (ret < 0) {
 921                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 922                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 923                 return -1;
 924         }
 925
 926         if (login->first_request)
 927                 if (iscsi_target_check_first_request(conn, login) < 0)
 928                         return -1;
 929
 930         if (iscsi_target_check_for_existing_instances(conn, login) < 0)
 931                 return -1;
 932
 933         ret = iscsi_encode_text_output(
 934                         PHASE_OPERATIONAL|PHASE_DECLARATIVE,
 935                         SENDER_TARGET,
 936                         login->rsp_buf,
 937                         &login->rsp_length,
 938                         conn->param_list,
 939                         conn->tpg->tpg_attrib.login_keys_workaround);
 940         if (ret < 0) {
 941                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 942                                 ISCSI_LOGIN_STATUS_INIT_ERR);
 943                 return -1;
 944         }
 945
 946         if (!login->auth_complete &&
 947              conn->tpg->tpg_attrib.authentication) {
 948                 pr_err("Initiator is requesting CSG: 1, has not been"
 949                          " successfully authenticated, and the Target is"
 950                         " enforcing iSCSI Authentication, login failed.\n");
 951                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
 952                                 ISCSI_LOGIN_STATUS_AUTH_FAILED);
 953                 return -1;
 954         }
 955
 956         if (!iscsi_check_negotiated_keys(conn->param_list))
 957                 if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE3) &&
 958                     (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT))
 959                         login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE3 |
 960                                             ISCSI_FLAG_LOGIN_TRANSIT;
 961
 962         return 0;
 963 }
 964
 965 static int iscsi_target_do_login(struct iscsi_conn *conn, struct iscsi_login *login)
 966 {
 967         int pdu_count = 0;
 968         struct iscsi_login_req *login_req;
 969         struct iscsi_login_rsp *login_rsp;
 970
 971         login_req = (struct iscsi_login_req *) login->req;
 972         login_rsp = (struct iscsi_login_rsp *) login->rsp;
 973
 974         while (1) {
 975                 if (++pdu_count > MAX_LOGIN_PDUS) {
 976                         pr_err("MAX_LOGIN_PDUS count reached.\n");
 977                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
 978                                         ISCSI_LOGIN_STATUS_TARGET_ERROR);
 979                         return -1;
 980                 }
 981
 982                 switch (ISCSI_LOGIN_CURRENT_STAGE(login_req->flags)) {
 983                 case 0:
 984                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK;
 985                         if (iscsi_target_handle_csg_zero(conn, login) < 0)
 986                                 return -1;
 987                         break;
 988                 case 1:
 989                         login_rsp->flags |= ISCSI_FLAG_LOGIN_CURRENT_STAGE1;
 990                         if (iscsi_target_handle_csg_one(conn, login) < 0)
 991                                 return -1;
 992                         if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
 993                                 /*
 994                                  * Check to make sure the TCP connection has not
 995                                  * dropped asynchronously while session reinstatement
 996                                  * was occuring in this kthread context, before
 997                                  * transitioning to full feature phase operation.
 998                                  */
 999                                 if (iscsi_target_sk_check_close(conn))
1000                                         return -1;
1001
1002                                 login->tsih = conn->sess->tsih;
1003                                 login->login_complete = 1;
1004                                 iscsi_target_restore_sock_callbacks(conn);
1005                                 if (iscsi_target_do_tx_login_io(conn,
1006                                                 login) < 0)
1007                                         return -1;
1008                                 return 1;
1009                         }
1010                         break;
1011                 default:
1012                         pr_err("Illegal CSG: %d received from"
1013                                 " Initiator, protocol error.\n",
1014                                 ISCSI_LOGIN_CURRENT_STAGE(login_req->flags));
1015                         break;
1016                 }
1017
1018                 if (iscsi_target_do_tx_login_io(conn, login) < 0)
1019                         return -1;
1020
1021                 if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
1022                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_TRANSIT;
1023                         login_rsp->flags &= ~ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
1024                 }
1025                 break;
1026         }
1027
1028         return 0;
1029 }
1030
1031 static void iscsi_initiatorname_tolower(
1032         char *param_buf)
1033 {
1034         char *c;
1035         u32 iqn_size = strlen(param_buf), i;
1036
1037         for (i = 0; i < iqn_size; i++) {
1038                 c = &param_buf[i];
1039                 if (!isupper(*c))
1040                         continue;
1041
1042                 *c = tolower(*c);
1043         }
1044 }
1045
1046 /*
1047  * Processes the first Login Request..
1048  */
1049 int iscsi_target_locate_portal(
1050         struct iscsi_np *np,
1051         struct iscsi_conn *conn,
1052         struct iscsi_login *login)
1053 {
1054         char *i_buf = NULL, *s_buf = NULL, *t_buf = NULL;
1055         char *tmpbuf, *start = NULL, *end = NULL, *key, *value;
1056         struct iscsi_session *sess = conn->sess;
1057         struct iscsi_tiqn *tiqn;
1058         struct iscsi_tpg_np *tpg_np = NULL;
1059         struct iscsi_login_req *login_req;
1060         struct se_node_acl *se_nacl;
1061         u32 payload_length, queue_depth = 0;
1062         int sessiontype = 0, ret = 0, tag_num, tag_size;
1063
1064         INIT_DELAYED_WORK(&conn->login_work, iscsi_target_do_login_rx);
1065         iscsi_target_set_sock_callbacks(conn);
1066
1067         login->np = np;
1068
1069         login_req = (struct iscsi_login_req *) login->req;
1070         payload_length = ntoh24(login_req->dlength);
1071
1072         tmpbuf = kzalloc(payload_length + 1, GFP_KERNEL);
1073         if (!tmpbuf) {
1074                 pr_err("Unable to allocate memory for tmpbuf.\n");
1075                 return -1;
1076         }
1077
1078         memcpy(tmpbuf, login->req_buf, payload_length);
1079         tmpbuf[payload_length] = '\0';
1080         start = tmpbuf;
1081         end = (start + payload_length);
1082
1083         /*
1084          * Locate the initial keys expected from the Initiator node in
1085          * the first login request in order to progress with the login phase.
1086          */
1087         while (start < end) {
1088                 if (iscsi_extract_key_value(start, &key, &value) < 0) {
1089                         ret = -1;
1090                         goto out;
1091                 }
1092
1093                 if (!strncmp(key, "InitiatorName", 13))
1094                         i_buf = value;
1095                 else if (!strncmp(key, "SessionType", 11))
1096                         s_buf = value;
1097                 else if (!strncmp(key, "TargetName", 10))
1098                         t_buf = value;
1099
1100                 start += strlen(key) + strlen(value) + 2;
1101         }
1102         /*
1103          * See 5.3.  Login Phase.
1104          */
1105         if (!i_buf) {
1106                 pr_err("InitiatorName key not received"
1107                         " in first login request.\n");
1108                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1109                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1110                 ret = -1;
1111                 goto out;
1112         }
1113         /*
1114          * Convert the incoming InitiatorName to lowercase following
1115          * RFC-3720 3.2.6.1. section c) that says that iSCSI IQNs
1116          * are NOT case sensitive.
1117          */
1118         iscsi_initiatorname_tolower(i_buf);
1119
1120         if (!s_buf) {
1121                 if (!login->leading_connection)
1122                         goto get_target;
1123
1124                 pr_err("SessionType key not received"
1125                         " in first login request.\n");
1126                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1127                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1128                 ret = -1;
1129                 goto out;
1130         }
1131
1132         /*
1133          * Use default portal group for discovery sessions.
1134          */
1135         sessiontype = strncmp(s_buf, DISCOVERY, 9);
1136         if (!sessiontype) {
1137                 conn->tpg = iscsit_global->discovery_tpg;
1138                 if (!login->leading_connection)
1139                         goto get_target;
1140
1141                 sess->sess_ops->SessionType = 1;
1142                 /*
1143                  * Setup crc32c modules from libcrypto
1144                  */
1145                 if (iscsi_login_setup_crypto(conn) < 0) {
1146                         pr_err("iscsi_login_setup_crypto() failed\n");
1147                         ret = -1;
1148                         goto out;
1149                 }
1150                 /*
1151                  * Serialize access across the discovery struct iscsi_portal_group to
1152                  * process login attempt.
1153                  */
1154                 if (iscsit_access_np(np, conn->tpg) < 0) {
1155                         iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1156                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1157                         ret = -1;
1158                         goto out;
1159                 }
1160                 ret = 0;
1161                 goto alloc_tags;
1162         }
1163
1164 get_target:
1165         if (!t_buf) {
1166                 pr_err("TargetName key not received"
1167                         " in first login request while"
1168                         " SessionType=Normal.\n");
1169                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1170                         ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1171                 ret = -1;
1172                 goto out;
1173         }
1174
1175         /*
1176          * Locate Target IQN from Storage Node.
1177          */
1178         tiqn = iscsit_get_tiqn_for_login(t_buf);
1179         if (!tiqn) {
1180                 pr_err("Unable to locate Target IQN: %s in"
1181                         " Storage Node\n", t_buf);
1182                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1183                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1184                 ret = -1;
1185                 goto out;
1186         }
1187         pr_debug("Located Storage Object: %s\n", tiqn->tiqn);
1188
1189         /*
1190          * Locate Target Portal Group from Storage Node.
1191          */
1192         conn->tpg = iscsit_get_tpg_from_np(tiqn, np, &tpg_np);
1193         if (!conn->tpg) {
1194                 pr_err("Unable to locate Target Portal Group"
1195                                 " on %s\n", tiqn->tiqn);
1196                 iscsit_put_tiqn_for_login(tiqn);
1197                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1198                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1199                 ret = -1;
1200                 goto out;
1201         }
1202         conn->tpg_np = tpg_np;
1203         pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
1204         /*
1205          * Setup crc32c modules from libcrypto
1206          */
1207         if (iscsi_login_setup_crypto(conn) < 0) {
1208                 pr_err("iscsi_login_setup_crypto() failed\n");
1209                 kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1210                 iscsit_put_tiqn_for_login(tiqn);
1211                 conn->tpg = NULL;
1212                 ret = -1;
1213                 goto out;
1214         }
1215         /*
1216          * Serialize access across the struct iscsi_portal_group to
1217          * process login attempt.
1218          */
1219         if (iscsit_access_np(np, conn->tpg) < 0) {
1220                 kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1221                 iscsit_put_tiqn_for_login(tiqn);
1222                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1223                                 ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1224                 conn->tpg = NULL;
1225                 ret = -1;
1226                 goto out;
1227         }
1228
1229         /*
1230          * conn->sess->node_acl will be set when the referenced
1231          * struct iscsi_session is located from received ISID+TSIH in
1232          * iscsi_login_non_zero_tsih_s2().
1233          */
1234         if (!login->leading_connection) {
1235                 ret = 0;
1236                 goto out;
1237         }
1238
1239         /*
1240          * This value is required in iscsi_login_zero_tsih_s2()
1241          */
1242         sess->sess_ops->SessionType = 0;
1243
1244         /*
1245          * Locate incoming Initiator IQN reference from Storage Node.
1246          */
1247         sess->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1248                         &conn->tpg->tpg_se_tpg, i_buf);
1249         if (!sess->se_sess->se_node_acl) {
1250                 pr_err("iSCSI Initiator Node: %s is not authorized to"
1251                         " access iSCSI target portal group: %hu.\n",
1252                                 i_buf, conn->tpg->tpgt);
1253                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1254                                 ISCSI_LOGIN_STATUS_TGT_FORBIDDEN);
1255                 ret = -1;
1256                 goto out;
1257         }
1258         se_nacl = sess->se_sess->se_node_acl;
1259         queue_depth = se_nacl->queue_depth;
1260         /*
1261          * Setup pre-allocated tags based upon allowed per NodeACL CmdSN
1262          * depth for non immediate commands, plus extra tags for immediate
1263          * commands.
1264          *
1265          * Also enforce a ISCSIT_MIN_TAGS to prevent unnecessary contention
1266          * in per-cpu-ida tag allocation logic + small queue_depth.
1267          */
1268 alloc_tags:
1269         tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
1270         tag_num = (tag_num * 2) + ISCSIT_EXTRA_TAGS;
1271         tag_size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
1272
1273         ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);
1274         if (ret < 0) {
1275                 iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1276                                     ISCSI_LOGIN_STATUS_NO_RESOURCES);
1277                 ret = -1;
1278         }
1279 out:
1280         kfree(tmpbuf);
1281         return ret;
1282 }
1283
1284 int iscsi_target_start_negotiation(
1285         struct iscsi_login *login,
1286         struct iscsi_conn *conn)
1287 {
1288         int ret;
1289
1290         if (conn->sock) {
1291                 struct sock *sk = conn->sock->sk;
1292
1293                 write_lock_bh(&sk->sk_callback_lock);
1294                 set_bit(LOGIN_FLAGS_READY, &conn->login_flags);
1295                 set_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
1296                 write_unlock_bh(&sk->sk_callback_lock);
1297         }
1298         /*
1299          * If iscsi_target_do_login returns zero to signal more PDU
1300          * exchanges are required to complete the login, go ahead and
1301          * clear LOGIN_FLAGS_INITIAL_PDU but only if the TCP connection
1302          * is still active.
1303          *
1304          * Otherwise if TCP connection dropped asynchronously, go ahead
1305          * and perform connection cleanup now.
1306          */
1307         ret = iscsi_target_do_login(conn, login);
1308         if (!ret && iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_INITIAL_PDU))
1309                 ret = -1;
1310
1311         if (ret < 0) {
1312                 cancel_delayed_work_sync(&conn->login_work);
1313                 iscsi_target_restore_sock_callbacks(conn);
1314                 iscsi_remove_failed_auth_entry(conn);
1315         }
1316         if (ret != 0)
1317                 iscsi_target_nego_release(conn);
1318
1319         return ret;
1320 }
1321
1322 void iscsi_target_nego_release(struct iscsi_conn *conn)
1323 {
1324         struct iscsi_login *login = conn->conn_login;
1325
1326         if (!login)
1327                 return;
1328
1329         kfree(login->req_buf);
1330         kfree(login->rsp_buf);
1331         kfree(login);
1332
1333         conn->conn_login = NULL;
1334 }