xref: /linux/drivers/target/iscsi/iscsi_target_nego.c (revision f5db340f19f14a8df9dfd22d71fba1513e9f1f7e)
1 /*******************************************************************************
2  * This file contains main functions related to iSCSI Parameter negotiation.
3  *
4  * (c) Copyright 2007-2013 Datera, Inc.
5  *
6  * Author: Nicholas A. Bellinger <nab@linux-iscsi.org>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  ******************************************************************************/
18 
19 #include <linux/ctype.h>
20 #include <linux/kthread.h>
21 #include <linux/slab.h>
22 #include <linux/sched/signal.h>
23 #include <net/sock.h>
24 #include <scsi/iscsi_proto.h>
25 #include <target/target_core_base.h>
26 #include <target/target_core_fabric.h>
27 #include <target/iscsi/iscsi_transport.h>
28 
29 #include <target/iscsi/iscsi_target_core.h>
30 #include "iscsi_target_parameters.h"
31 #include "iscsi_target_login.h"
32 #include "iscsi_target_nego.h"
33 #include "iscsi_target_tpg.h"
34 #include "iscsi_target_util.h"
35 #include "iscsi_target.h"
36 #include "iscsi_target_auth.h"
37 
38 #define MAX_LOGIN_PDUS  7
39 #define TEXT_LEN	4096
40 
41 void convert_null_to_semi(char *buf, int len)
42 {
43 	int i;
44 
45 	for (i = 0; i < len; i++)
46 		if (buf[i] == '\0')
47 			buf[i] = ';';
48 }
49 
50 static int strlen_semi(char *buf)
51 {
52 	int i = 0;
53 
54 	while (buf[i] != '\0') {
55 		if (buf[i] == ';')
56 			return i;
57 		i++;
58 	}
59 
60 	return -1;
61 }
62 
63 int extract_param(
64 	const char *in_buf,
65 	const char *pattern,
66 	unsigned int max_length,
67 	char *out_buf,
68 	unsigned char *type)
69 {
70 	char *ptr;
71 	int len;
72 
73 	if (!in_buf || !pattern || !out_buf || !type)
74 		return -1;
75 
76 	ptr = strstr(in_buf, pattern);
77 	if (!ptr)
78 		return -1;
79 
80 	ptr = strstr(ptr, "=");
81 	if (!ptr)
82 		return -1;
83 
84 	ptr += 1;
85 	if (*ptr == '0' && (*(ptr+1) == 'x' || *(ptr+1) == 'X')) {
86 		ptr += 2; /* skip 0x */
87 		*type = HEX;
88 	} else
89 		*type = DECIMAL;
90 
91 	len = strlen_semi(ptr);
92 	if (len < 0)
93 		return -1;
94 
95 	if (len >= max_length) {
96 		pr_err("Length of input: %d exceeds max_length:"
97 			" %d\n", len, max_length);
98 		return -1;
99 	}
100 	memcpy(out_buf, ptr, len);
101 	out_buf[len] = '\0';
102 
103 	return 0;
104 }
105 
106 static u32 iscsi_handle_authentication(
107 	struct iscsi_conn *conn,
108 	char *in_buf,
109 	char *out_buf,
110 	int in_length,
111 	int *out_length,
112 	unsigned char *authtype)
113 {
114 	struct iscsi_session *sess = conn->sess;
115 	struct iscsi_node_auth *auth;
116 	struct iscsi_node_acl *iscsi_nacl;
117 	struct iscsi_portal_group *iscsi_tpg;
118 	struct se_node_acl *se_nacl;
119 
120 	if (!sess->sess_ops->SessionType) {
121 		/*
122 		 * For SessionType=Normal
123 		 */
124 		se_nacl = conn->sess->se_sess->se_node_acl;
125 		if (!se_nacl) {
126 			pr_err("Unable to locate struct se_node_acl for"
127 					" CHAP auth\n");
128 			return -1;
129 		}
130 		iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
131 				se_node_acl);
132 		if (!iscsi_nacl) {
133 			pr_err("Unable to locate struct iscsi_node_acl for"
134 					" CHAP auth\n");
135 			return -1;
136 		}
137 
138 		if (se_nacl->dynamic_node_acl) {
139 			iscsi_tpg = container_of(se_nacl->se_tpg,
140 					struct iscsi_portal_group, tpg_se_tpg);
141 
142 			auth = &iscsi_tpg->tpg_demo_auth;
143 		} else {
144 			iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
145 						  se_node_acl);
146 
147 			auth = &iscsi_nacl->node_auth;
148 		}
149 	} else {
150 		/*
151 		 * For SessionType=Discovery
152 		 */
153 		auth = &iscsit_global->discovery_acl.node_auth;
154 	}
155 
156 	if (strstr("CHAP", authtype))
157 		strcpy(conn->sess->auth_type, "CHAP");
158 	else
159 		strcpy(conn->sess->auth_type, NONE);
160 
161 	if (strstr("None", authtype))
162 		return 1;
163 #ifdef CANSRP
164 	else if (strstr("SRP", authtype))
165 		return srp_main_loop(conn, auth, in_buf, out_buf,
166 				&in_length, out_length);
167 #endif
168 	else if (strstr("CHAP", authtype))
169 		return chap_main_loop(conn, auth, in_buf, out_buf,
170 				&in_length, out_length);
171 	else if (strstr("SPKM1", authtype))
172 		return 2;
173 	else if (strstr("SPKM2", authtype))
174 		return 2;
175 	else if (strstr("KRB5", authtype))
176 		return 2;
177 	else
178 		return 2;
179 }
180 
181 static void iscsi_remove_failed_auth_entry(struct iscsi_conn *conn)
182 {
183 	kfree(conn->auth_protocol);
184 }
185 
186 int iscsi_target_check_login_request(
187 	struct iscsi_conn *conn,
188 	struct iscsi_login *login)
189 {
190 	int req_csg, req_nsg;
191 	u32 payload_length;
192 	struct iscsi_login_req *login_req;
193 
194 	login_req = (struct iscsi_login_req *) login->req;
195 	payload_length = ntoh24(login_req->dlength);
196 
197 	switch (login_req->opcode & ISCSI_OPCODE_MASK) {
198 	case ISCSI_OP_LOGIN:
199 		break;
200 	default:
201 		pr_err("Received unknown opcode 0x%02x.\n",
202 				login_req->opcode & ISCSI_OPCODE_MASK);
203 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
204 				ISCSI_LOGIN_STATUS_INIT_ERR);
205 		return -1;
206 	}
207 
208 	if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
209 	    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
210 		pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
211 			" and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
212 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
213 				ISCSI_LOGIN_STATUS_INIT_ERR);
214 		return -1;
215 	}
216 
217 	req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
218 	req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);
219 
220 	if (req_csg != login->current_stage) {
221 		pr_err("Initiator unexpectedly changed login stage"
222 			" from %d to %d, login failed.\n", login->current_stage,
223 			req_csg);
224 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
225 				ISCSI_LOGIN_STATUS_INIT_ERR);
226 		return -1;
227 	}
228 
229 	if ((req_nsg == 2) || (req_csg >= 2) ||
230 	   ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
231 	    (req_nsg <= req_csg))) {
232 		pr_err("Illegal login_req->flags Combination, CSG: %d,"
233 			" NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
234 			req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
235 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
236 				ISCSI_LOGIN_STATUS_INIT_ERR);
237 		return -1;
238 	}
239 
240 	if ((login_req->max_version != login->version_max) ||
241 	    (login_req->min_version != login->version_min)) {
242 		pr_err("Login request changed Version Max/Nin"
243 			" unexpectedly to 0x%02x/0x%02x, protocol error\n",
244 			login_req->max_version, login_req->min_version);
245 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
246 				ISCSI_LOGIN_STATUS_INIT_ERR);
247 		return -1;
248 	}
249 
250 	if (memcmp(login_req->isid, login->isid, 6) != 0) {
251 		pr_err("Login request changed ISID unexpectedly,"
252 				" protocol error.\n");
253 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
254 				ISCSI_LOGIN_STATUS_INIT_ERR);
255 		return -1;
256 	}
257 
258 	if (login_req->itt != login->init_task_tag) {
259 		pr_err("Login request changed ITT unexpectedly to"
260 			" 0x%08x, protocol error.\n", login_req->itt);
261 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
262 				ISCSI_LOGIN_STATUS_INIT_ERR);
263 		return -1;
264 	}
265 
266 	if (payload_length > MAX_KEY_VALUE_PAIRS) {
267 		pr_err("Login request payload exceeds default"
268 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
269 				MAX_KEY_VALUE_PAIRS);
270 		return -1;
271 	}
272 
273 	return 0;
274 }
275 EXPORT_SYMBOL(iscsi_target_check_login_request);
276 
277 static int iscsi_target_check_first_request(
278 	struct iscsi_conn *conn,
279 	struct iscsi_login *login)
280 {
281 	struct iscsi_param *param = NULL;
282 	struct se_node_acl *se_nacl;
283 
284 	login->first_request = 0;
285 
286 	list_for_each_entry(param, &conn->param_list->param_list, p_list) {
287 		if (!strncmp(param->name, SESSIONTYPE, 11)) {
288 			if (!IS_PSTATE_ACCEPTOR(param)) {
289 				pr_err("SessionType key not received"
290 					" in first login request.\n");
291 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
292 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
293 				return -1;
294 			}
295 			if (!strncmp(param->value, DISCOVERY, 9))
296 				return 0;
297 		}
298 
299 		if (!strncmp(param->name, INITIATORNAME, 13)) {
300 			if (!IS_PSTATE_ACCEPTOR(param)) {
301 				if (!login->leading_connection)
302 					continue;
303 
304 				pr_err("InitiatorName key not received"
305 					" in first login request.\n");
306 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
307 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
308 				return -1;
309 			}
310 
311 			/*
312 			 * For non-leading connections, double check that the
313 			 * received InitiatorName matches the existing session's
314 			 * struct iscsi_node_acl.
315 			 */
316 			if (!login->leading_connection) {
317 				se_nacl = conn->sess->se_sess->se_node_acl;
318 				if (!se_nacl) {
319 					pr_err("Unable to locate"
320 						" struct se_node_acl\n");
321 					iscsit_tx_login_rsp(conn,
322 							ISCSI_STATUS_CLS_INITIATOR_ERR,
323 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
324 					return -1;
325 				}
326 
327 				if (strcmp(param->value,
328 						se_nacl->initiatorname)) {
329 					pr_err("Incorrect"
330 						" InitiatorName: %s for this"
331 						" iSCSI Initiator Node.\n",
332 						param->value);
333 					iscsit_tx_login_rsp(conn,
334 							ISCSI_STATUS_CLS_INITIATOR_ERR,
335 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
336 					return -1;
337 				}
338 			}
339 		}
340 	}
341 
342 	return 0;
343 }
344 
345 static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
346 {
347 	u32 padding = 0;
348 	struct iscsi_login_rsp *login_rsp;
349 
350 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
351 
352 	login_rsp->opcode		= ISCSI_OP_LOGIN_RSP;
353 	hton24(login_rsp->dlength, login->rsp_length);
354 	memcpy(login_rsp->isid, login->isid, 6);
355 	login_rsp->tsih			= cpu_to_be16(login->tsih);
356 	login_rsp->itt			= login->init_task_tag;
357 	login_rsp->statsn		= cpu_to_be32(conn->stat_sn++);
358 	login_rsp->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
359 	login_rsp->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
360 
361 	pr_debug("Sending Login Response, Flags: 0x%02x, ITT: 0x%08x,"
362 		" ExpCmdSN; 0x%08x, MaxCmdSN: 0x%08x, StatSN: 0x%08x, Length:"
363 		" %u\n", login_rsp->flags, (__force u32)login_rsp->itt,
364 		ntohl(login_rsp->exp_cmdsn), ntohl(login_rsp->max_cmdsn),
365 		ntohl(login_rsp->statsn), login->rsp_length);
366 
367 	padding = ((-login->rsp_length) & 3);
368 	/*
369 	 * Before sending the last login response containing the transition
370 	 * bit for full-feature-phase, go ahead and start up TX/RX threads
371 	 * now to avoid potential resource allocation failures after the
372 	 * final login response has been sent.
373 	 */
374 	if (login->login_complete) {
375 		int rc = iscsit_start_kthreads(conn);
376 		if (rc) {
377 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
378 					    ISCSI_LOGIN_STATUS_NO_RESOURCES);
379 			return -1;
380 		}
381 	}
382 
383 	if (conn->conn_transport->iscsit_put_login_tx(conn, login,
384 					login->rsp_length + padding) < 0)
385 		goto err;
386 
387 	login->rsp_length		= 0;
388 
389 	return 0;
390 
391 err:
392 	if (login->login_complete) {
393 		if (conn->rx_thread && conn->rx_thread_active) {
394 			send_sig(SIGINT, conn->rx_thread, 1);
395 			complete(&conn->rx_login_comp);
396 			kthread_stop(conn->rx_thread);
397 		}
398 		if (conn->tx_thread && conn->tx_thread_active) {
399 			send_sig(SIGINT, conn->tx_thread, 1);
400 			kthread_stop(conn->tx_thread);
401 		}
402 		spin_lock(&iscsit_global->ts_bitmap_lock);
403 		bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
404 				      get_order(1));
405 		spin_unlock(&iscsit_global->ts_bitmap_lock);
406 	}
407 	return -1;
408 }
409 
410 static void iscsi_target_sk_data_ready(struct sock *sk)
411 {
412 	struct iscsi_conn *conn = sk->sk_user_data;
413 	bool rc;
414 
415 	pr_debug("Entering iscsi_target_sk_data_ready: conn: %p\n", conn);
416 
417 	write_lock_bh(&sk->sk_callback_lock);
418 	if (!sk->sk_user_data) {
419 		write_unlock_bh(&sk->sk_callback_lock);
420 		return;
421 	}
422 	if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
423 		write_unlock_bh(&sk->sk_callback_lock);
424 		pr_debug("Got LOGIN_FLAGS_READY=0, conn: %p >>>>\n", conn);
425 		return;
426 	}
427 	if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
428 		write_unlock_bh(&sk->sk_callback_lock);
429 		pr_debug("Got LOGIN_FLAGS_CLOSED=1, conn: %p >>>>\n", conn);
430 		return;
431 	}
432 	if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) {
433 		write_unlock_bh(&sk->sk_callback_lock);
434 		pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p >>>>\n", conn);
435 		return;
436 	}
437 
438 	rc = schedule_delayed_work(&conn->login_work, 0);
439 	if (!rc) {
440 		pr_debug("iscsi_target_sk_data_ready, schedule_delayed_work"
441 			 " got false\n");
442 	}
443 	write_unlock_bh(&sk->sk_callback_lock);
444 }
445 
446 static void iscsi_target_sk_state_change(struct sock *);
447 
448 static void iscsi_target_set_sock_callbacks(struct iscsi_conn *conn)
449 {
450 	struct sock *sk;
451 
452 	if (!conn->sock)
453 		return;
454 
455 	sk = conn->sock->sk;
456 	pr_debug("Entering iscsi_target_set_sock_callbacks: conn: %p\n", conn);
457 
458 	write_lock_bh(&sk->sk_callback_lock);
459 	sk->sk_user_data = conn;
460 	conn->orig_data_ready = sk->sk_data_ready;
461 	conn->orig_state_change = sk->sk_state_change;
462 	sk->sk_data_ready = iscsi_target_sk_data_ready;
463 	sk->sk_state_change = iscsi_target_sk_state_change;
464 	write_unlock_bh(&sk->sk_callback_lock);
465 
466 	sk->sk_sndtimeo = TA_LOGIN_TIMEOUT * HZ;
467 	sk->sk_rcvtimeo = TA_LOGIN_TIMEOUT * HZ;
468 }
469 
470 static void iscsi_target_restore_sock_callbacks(struct iscsi_conn *conn)
471 {
472 	struct sock *sk;
473 
474 	if (!conn->sock)
475 		return;
476 
477 	sk = conn->sock->sk;
478 	pr_debug("Entering iscsi_target_restore_sock_callbacks: conn: %p\n", conn);
479 
480 	write_lock_bh(&sk->sk_callback_lock);
481 	if (!sk->sk_user_data) {
482 		write_unlock_bh(&sk->sk_callback_lock);
483 		return;
484 	}
485 	sk->sk_user_data = NULL;
486 	sk->sk_data_ready = conn->orig_data_ready;
487 	sk->sk_state_change = conn->orig_state_change;
488 	write_unlock_bh(&sk->sk_callback_lock);
489 
490 	sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
491 	sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
492 }
493 
494 static int iscsi_target_do_login(struct iscsi_conn *, struct iscsi_login *);
495 
496 static bool __iscsi_target_sk_check_close(struct sock *sk)
497 {
498 	if (sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) {
499 		pr_debug("__iscsi_target_sk_check_close: TCP_CLOSE_WAIT|TCP_CLOSE,"
500 			"returning FALSE\n");
501 		return true;
502 	}
503 	return false;
504 }
505 
506 static bool iscsi_target_sk_check_close(struct iscsi_conn *conn)
507 {
508 	bool state = false;
509 
510 	if (conn->sock) {
511 		struct sock *sk = conn->sock->sk;
512 
513 		read_lock_bh(&sk->sk_callback_lock);
514 		state = (__iscsi_target_sk_check_close(sk) ||
515 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
516 		read_unlock_bh(&sk->sk_callback_lock);
517 	}
518 	return state;
519 }
520 
521 static bool iscsi_target_sk_check_flag(struct iscsi_conn *conn, unsigned int flag)
522 {
523 	bool state = false;
524 
525 	if (conn->sock) {
526 		struct sock *sk = conn->sock->sk;
527 
528 		read_lock_bh(&sk->sk_callback_lock);
529 		state = test_bit(flag, &conn->login_flags);
530 		read_unlock_bh(&sk->sk_callback_lock);
531 	}
532 	return state;
533 }
534 
535 static bool iscsi_target_sk_check_and_clear(struct iscsi_conn *conn, unsigned int flag)
536 {
537 	bool state = false;
538 
539 	if (conn->sock) {
540 		struct sock *sk = conn->sock->sk;
541 
542 		write_lock_bh(&sk->sk_callback_lock);
543 		state = (__iscsi_target_sk_check_close(sk) ||
544 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
545 		if (!state)
546 			clear_bit(flag, &conn->login_flags);
547 		write_unlock_bh(&sk->sk_callback_lock);
548 	}
549 	return state;
550 }
551 
552 static void iscsi_target_login_drop(struct iscsi_conn *conn, struct iscsi_login *login)
553 {
554 	struct iscsi_np *np = login->np;
555 	bool zero_tsih = login->zero_tsih;
556 
557 	iscsi_remove_failed_auth_entry(conn);
558 	iscsi_target_nego_release(conn);
559 	iscsi_target_login_sess_out(conn, np, zero_tsih, true);
560 }
561 
562 static void iscsi_target_login_timeout(unsigned long data)
563 {
564 	struct iscsi_conn *conn = (struct iscsi_conn *)data;
565 
566 	pr_debug("Entering iscsi_target_login_timeout >>>>>>>>>>>>>>>>>>>\n");
567 
568 	if (conn->login_kworker) {
569 		pr_debug("Sending SIGINT to conn->login_kworker %s/%d\n",
570 			 conn->login_kworker->comm, conn->login_kworker->pid);
571 		send_sig(SIGINT, conn->login_kworker, 1);
572 	}
573 }
574 
575 static void iscsi_target_do_login_rx(struct work_struct *work)
576 {
577 	struct iscsi_conn *conn = container_of(work,
578 				struct iscsi_conn, login_work.work);
579 	struct iscsi_login *login = conn->login;
580 	struct iscsi_np *np = login->np;
581 	struct iscsi_portal_group *tpg = conn->tpg;
582 	struct iscsi_tpg_np *tpg_np = conn->tpg_np;
583 	struct timer_list login_timer;
584 	int rc, zero_tsih = login->zero_tsih;
585 	bool state;
586 
587 	pr_debug("entering iscsi_target_do_login_rx, conn: %p, %s:%d\n",
588 			conn, current->comm, current->pid);
589 	/*
590 	 * If iscsi_target_do_login_rx() has been invoked by ->sk_data_ready()
591 	 * before initial PDU processing in iscsi_target_start_negotiation()
592 	 * has completed, go ahead and retry until it's cleared.
593 	 *
594 	 * Otherwise if the TCP connection drops while this is occuring,
595 	 * iscsi_target_start_negotiation() will detect the failure, call
596 	 * cancel_delayed_work_sync(&conn->login_work), and cleanup the
597 	 * remaining iscsi connection resources from iscsi_np process context.
598 	 */
599 	if (iscsi_target_sk_check_flag(conn, LOGIN_FLAGS_INITIAL_PDU)) {
600 		schedule_delayed_work(&conn->login_work, msecs_to_jiffies(10));
601 		return;
602 	}
603 
604 	spin_lock(&tpg->tpg_state_lock);
605 	state = (tpg->tpg_state == TPG_STATE_ACTIVE);
606 	spin_unlock(&tpg->tpg_state_lock);
607 
608 	if (!state) {
609 		pr_debug("iscsi_target_do_login_rx: tpg_state != TPG_STATE_ACTIVE\n");
610 		goto err;
611 	}
612 
613 	if (iscsi_target_sk_check_close(conn)) {
614 		pr_debug("iscsi_target_do_login_rx, TCP state CLOSE\n");
615 		goto err;
616 	}
617 
618 	conn->login_kworker = current;
619 	allow_signal(SIGINT);
620 
621 	init_timer(&login_timer);
622 	login_timer.expires = (get_jiffies_64() + TA_LOGIN_TIMEOUT * HZ);
623 	login_timer.data = (unsigned long)conn;
624 	login_timer.function = iscsi_target_login_timeout;
625 	add_timer(&login_timer);
626 	pr_debug("Starting login_timer for %s/%d\n", current->comm, current->pid);
627 
628 	rc = conn->conn_transport->iscsit_get_login_rx(conn, login);
629 	del_timer_sync(&login_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 }
1335