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 
32 void convert_null_to_semi(char *buf, int len)
33 {
34 	int i;
35 
36 	for (i = 0; i < len; i++)
37 		if (buf[i] == '\0')
38 			buf[i] = ';';
39 }
40 
41 static int strlen_semi(char *buf)
42 {
43 	int i = 0;
44 
45 	while (buf[i] != '\0') {
46 		if (buf[i] == ';')
47 			return i;
48 		i++;
49 	}
50 
51 	return -1;
52 }
53 
54 int extract_param(
55 	const char *in_buf,
56 	const char *pattern,
57 	unsigned int max_length,
58 	char *out_buf,
59 	unsigned char *type)
60 {
61 	char *ptr;
62 	int len;
63 
64 	if (!in_buf || !pattern || !out_buf || !type)
65 		return -1;
66 
67 	ptr = strstr(in_buf, pattern);
68 	if (!ptr)
69 		return -1;
70 
71 	ptr = strstr(ptr, "=");
72 	if (!ptr)
73 		return -1;
74 
75 	ptr += 1;
76 	if (*ptr == '0' && (*(ptr+1) == 'x' || *(ptr+1) == 'X')) {
77 		ptr += 2; /* skip 0x */
78 		*type = HEX;
79 	} else
80 		*type = DECIMAL;
81 
82 	len = strlen_semi(ptr);
83 	if (len < 0)
84 		return -1;
85 
86 	if (len >= max_length) {
87 		pr_err("Length of input: %d exceeds max_length:"
88 			" %d\n", len, max_length);
89 		return -1;
90 	}
91 	memcpy(out_buf, ptr, len);
92 	out_buf[len] = '\0';
93 
94 	return 0;
95 }
96 
97 static u32 iscsi_handle_authentication(
98 	struct iscsi_conn *conn,
99 	char *in_buf,
100 	char *out_buf,
101 	int in_length,
102 	int *out_length,
103 	unsigned char *authtype)
104 {
105 	struct iscsi_session *sess = conn->sess;
106 	struct iscsi_node_auth *auth;
107 	struct iscsi_node_acl *iscsi_nacl;
108 	struct iscsi_portal_group *iscsi_tpg;
109 	struct se_node_acl *se_nacl;
110 
111 	if (!sess->sess_ops->SessionType) {
112 		/*
113 		 * For SessionType=Normal
114 		 */
115 		se_nacl = conn->sess->se_sess->se_node_acl;
116 		if (!se_nacl) {
117 			pr_err("Unable to locate struct se_node_acl for"
118 					" CHAP auth\n");
119 			return -1;
120 		}
121 
122 		if (se_nacl->dynamic_node_acl) {
123 			iscsi_tpg = container_of(se_nacl->se_tpg,
124 					struct iscsi_portal_group, tpg_se_tpg);
125 
126 			auth = &iscsi_tpg->tpg_demo_auth;
127 		} else {
128 			iscsi_nacl = container_of(se_nacl, struct iscsi_node_acl,
129 						  se_node_acl);
130 
131 			auth = &iscsi_nacl->node_auth;
132 		}
133 	} else {
134 		/*
135 		 * For SessionType=Discovery
136 		 */
137 		auth = &iscsit_global->discovery_acl.node_auth;
138 	}
139 
140 	if (strstr("CHAP", authtype))
141 		strcpy(conn->sess->auth_type, "CHAP");
142 	else
143 		strcpy(conn->sess->auth_type, NONE);
144 
145 	if (strstr("None", authtype))
146 		return 1;
147 	else if (strstr("CHAP", authtype))
148 		return chap_main_loop(conn, auth, in_buf, out_buf,
149 				&in_length, out_length);
150 	/* SRP, SPKM1, SPKM2 and KRB5 are unsupported */
151 	return 2;
152 }
153 
154 static void iscsi_remove_failed_auth_entry(struct iscsi_conn *conn)
155 {
156 	kfree(conn->auth_protocol);
157 }
158 
159 int iscsi_target_check_login_request(
160 	struct iscsi_conn *conn,
161 	struct iscsi_login *login)
162 {
163 	int req_csg, req_nsg;
164 	u32 payload_length;
165 	struct iscsi_login_req *login_req;
166 
167 	login_req = (struct iscsi_login_req *) login->req;
168 	payload_length = ntoh24(login_req->dlength);
169 
170 	switch (login_req->opcode & ISCSI_OPCODE_MASK) {
171 	case ISCSI_OP_LOGIN:
172 		break;
173 	default:
174 		pr_err("Received unknown opcode 0x%02x.\n",
175 				login_req->opcode & ISCSI_OPCODE_MASK);
176 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
177 				ISCSI_LOGIN_STATUS_INIT_ERR);
178 		return -1;
179 	}
180 
181 	if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
182 	    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
183 		pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
184 			" and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
185 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
186 				ISCSI_LOGIN_STATUS_INIT_ERR);
187 		return -1;
188 	}
189 
190 	req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
191 	req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);
192 
193 	if (req_csg != login->current_stage) {
194 		pr_err("Initiator unexpectedly changed login stage"
195 			" from %d to %d, login failed.\n", login->current_stage,
196 			req_csg);
197 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
198 				ISCSI_LOGIN_STATUS_INIT_ERR);
199 		return -1;
200 	}
201 
202 	if ((req_nsg == 2) || (req_csg >= 2) ||
203 	   ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
204 	    (req_nsg <= req_csg))) {
205 		pr_err("Illegal login_req->flags Combination, CSG: %d,"
206 			" NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
207 			req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
208 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
209 				ISCSI_LOGIN_STATUS_INIT_ERR);
210 		return -1;
211 	}
212 
213 	if ((login_req->max_version != login->version_max) ||
214 	    (login_req->min_version != login->version_min)) {
215 		pr_err("Login request changed Version Max/Nin"
216 			" unexpectedly to 0x%02x/0x%02x, protocol error\n",
217 			login_req->max_version, login_req->min_version);
218 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
219 				ISCSI_LOGIN_STATUS_INIT_ERR);
220 		return -1;
221 	}
222 
223 	if (memcmp(login_req->isid, login->isid, 6) != 0) {
224 		pr_err("Login request changed ISID unexpectedly,"
225 				" protocol error.\n");
226 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
227 				ISCSI_LOGIN_STATUS_INIT_ERR);
228 		return -1;
229 	}
230 
231 	if (login_req->itt != login->init_task_tag) {
232 		pr_err("Login request changed ITT unexpectedly to"
233 			" 0x%08x, protocol error.\n", login_req->itt);
234 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
235 				ISCSI_LOGIN_STATUS_INIT_ERR);
236 		return -1;
237 	}
238 
239 	if (payload_length > MAX_KEY_VALUE_PAIRS) {
240 		pr_err("Login request payload exceeds default"
241 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
242 				MAX_KEY_VALUE_PAIRS);
243 		return -1;
244 	}
245 
246 	return 0;
247 }
248 EXPORT_SYMBOL(iscsi_target_check_login_request);
249 
250 static int iscsi_target_check_first_request(
251 	struct iscsi_conn *conn,
252 	struct iscsi_login *login)
253 {
254 	struct iscsi_param *param = NULL;
255 	struct se_node_acl *se_nacl;
256 
257 	login->first_request = 0;
258 
259 	list_for_each_entry(param, &conn->param_list->param_list, p_list) {
260 		if (!strncmp(param->name, SESSIONTYPE, 11)) {
261 			if (!IS_PSTATE_ACCEPTOR(param)) {
262 				pr_err("SessionType key not received"
263 					" in first login request.\n");
264 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
265 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
266 				return -1;
267 			}
268 			if (!strncmp(param->value, DISCOVERY, 9))
269 				return 0;
270 		}
271 
272 		if (!strncmp(param->name, INITIATORNAME, 13)) {
273 			if (!IS_PSTATE_ACCEPTOR(param)) {
274 				if (!login->leading_connection)
275 					continue;
276 
277 				pr_err("InitiatorName key not received"
278 					" in first login request.\n");
279 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
280 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
281 				return -1;
282 			}
283 
284 			/*
285 			 * For non-leading connections, double check that the
286 			 * received InitiatorName matches the existing session's
287 			 * struct iscsi_node_acl.
288 			 */
289 			if (!login->leading_connection) {
290 				se_nacl = conn->sess->se_sess->se_node_acl;
291 				if (!se_nacl) {
292 					pr_err("Unable to locate"
293 						" struct se_node_acl\n");
294 					iscsit_tx_login_rsp(conn,
295 							ISCSI_STATUS_CLS_INITIATOR_ERR,
296 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
297 					return -1;
298 				}
299 
300 				if (strcmp(param->value,
301 						se_nacl->initiatorname)) {
302 					pr_err("Incorrect"
303 						" InitiatorName: %s for this"
304 						" iSCSI Initiator Node.\n",
305 						param->value);
306 					iscsit_tx_login_rsp(conn,
307 							ISCSI_STATUS_CLS_INITIATOR_ERR,
308 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
309 					return -1;
310 				}
311 			}
312 		}
313 	}
314 
315 	return 0;
316 }
317 
318 static int iscsi_target_do_tx_login_io(struct iscsi_conn *conn, struct iscsi_login *login)
319 {
320 	u32 padding = 0;
321 	struct iscsi_login_rsp *login_rsp;
322 
323 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
324 
325 	login_rsp->opcode		= ISCSI_OP_LOGIN_RSP;
326 	hton24(login_rsp->dlength, login->rsp_length);
327 	memcpy(login_rsp->isid, login->isid, 6);
328 	login_rsp->tsih			= cpu_to_be16(login->tsih);
329 	login_rsp->itt			= login->init_task_tag;
330 	login_rsp->statsn		= cpu_to_be32(conn->stat_sn++);
331 	login_rsp->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
332 	login_rsp->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
333 
334 	pr_debug("Sending Login Response, Flags: 0x%02x, ITT: 0x%08x,"
335 		" ExpCmdSN; 0x%08x, MaxCmdSN: 0x%08x, StatSN: 0x%08x, Length:"
336 		" %u\n", login_rsp->flags, (__force u32)login_rsp->itt,
337 		ntohl(login_rsp->exp_cmdsn), ntohl(login_rsp->max_cmdsn),
338 		ntohl(login_rsp->statsn), login->rsp_length);
339 
340 	padding = ((-login->rsp_length) & 3);
341 	/*
342 	 * Before sending the last login response containing the transition
343 	 * bit for full-feature-phase, go ahead and start up TX/RX threads
344 	 * now to avoid potential resource allocation failures after the
345 	 * final login response has been sent.
346 	 */
347 	if (login->login_complete) {
348 		int rc = iscsit_start_kthreads(conn);
349 		if (rc) {
350 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
351 					    ISCSI_LOGIN_STATUS_NO_RESOURCES);
352 			return -1;
353 		}
354 	}
355 
356 	if (conn->conn_transport->iscsit_put_login_tx(conn, login,
357 					login->rsp_length + padding) < 0)
358 		goto err;
359 
360 	login->rsp_length		= 0;
361 
362 	return 0;
363 
364 err:
365 	if (login->login_complete) {
366 		if (conn->rx_thread && conn->rx_thread_active) {
367 			send_sig(SIGINT, conn->rx_thread, 1);
368 			complete(&conn->rx_login_comp);
369 			kthread_stop(conn->rx_thread);
370 		}
371 		if (conn->tx_thread && conn->tx_thread_active) {
372 			send_sig(SIGINT, conn->tx_thread, 1);
373 			kthread_stop(conn->tx_thread);
374 		}
375 		spin_lock(&iscsit_global->ts_bitmap_lock);
376 		bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
377 				      get_order(1));
378 		spin_unlock(&iscsit_global->ts_bitmap_lock);
379 	}
380 	return -1;
381 }
382 
383 static void iscsi_target_sk_data_ready(struct sock *sk)
384 {
385 	struct iscsi_conn *conn = sk->sk_user_data;
386 	bool rc;
387 
388 	pr_debug("Entering iscsi_target_sk_data_ready: conn: %p\n", conn);
389 
390 	write_lock_bh(&sk->sk_callback_lock);
391 	if (!sk->sk_user_data) {
392 		write_unlock_bh(&sk->sk_callback_lock);
393 		return;
394 	}
395 	if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
396 		write_unlock_bh(&sk->sk_callback_lock);
397 		pr_debug("Got LOGIN_FLAGS_READY=0, conn: %p >>>>\n", conn);
398 		return;
399 	}
400 	if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
401 		write_unlock_bh(&sk->sk_callback_lock);
402 		pr_debug("Got LOGIN_FLAGS_CLOSED=1, conn: %p >>>>\n", conn);
403 		return;
404 	}
405 	if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) {
406 		write_unlock_bh(&sk->sk_callback_lock);
407 		pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p >>>>\n", conn);
408 		if (iscsi_target_sk_data_ready == conn->orig_data_ready)
409 			return;
410 		conn->orig_data_ready(sk);
411 		return;
412 	}
413 
414 	rc = schedule_delayed_work(&conn->login_work, 0);
415 	if (!rc) {
416 		pr_debug("iscsi_target_sk_data_ready, schedule_delayed_work"
417 			 " got false\n");
418 	}
419 	write_unlock_bh(&sk->sk_callback_lock);
420 }
421 
422 static void iscsi_target_sk_state_change(struct sock *);
423 
424 static void iscsi_target_set_sock_callbacks(struct iscsi_conn *conn)
425 {
426 	struct sock *sk;
427 
428 	if (!conn->sock)
429 		return;
430 
431 	sk = conn->sock->sk;
432 	pr_debug("Entering iscsi_target_set_sock_callbacks: conn: %p\n", conn);
433 
434 	write_lock_bh(&sk->sk_callback_lock);
435 	sk->sk_user_data = conn;
436 	conn->orig_data_ready = sk->sk_data_ready;
437 	conn->orig_state_change = sk->sk_state_change;
438 	sk->sk_data_ready = iscsi_target_sk_data_ready;
439 	sk->sk_state_change = iscsi_target_sk_state_change;
440 	write_unlock_bh(&sk->sk_callback_lock);
441 
442 	sk->sk_sndtimeo = TA_LOGIN_TIMEOUT * HZ;
443 	sk->sk_rcvtimeo = TA_LOGIN_TIMEOUT * HZ;
444 }
445 
446 static void iscsi_target_restore_sock_callbacks(struct iscsi_conn *conn)
447 {
448 	struct sock *sk;
449 
450 	if (!conn->sock)
451 		return;
452 
453 	sk = conn->sock->sk;
454 	pr_debug("Entering iscsi_target_restore_sock_callbacks: conn: %p\n", conn);
455 
456 	write_lock_bh(&sk->sk_callback_lock);
457 	if (!sk->sk_user_data) {
458 		write_unlock_bh(&sk->sk_callback_lock);
459 		return;
460 	}
461 	sk->sk_user_data = NULL;
462 	sk->sk_data_ready = conn->orig_data_ready;
463 	sk->sk_state_change = conn->orig_state_change;
464 	write_unlock_bh(&sk->sk_callback_lock);
465 
466 	sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
467 	sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
468 }
469 
470 static int iscsi_target_do_login(struct iscsi_conn *, struct iscsi_login *);
471 
472 static bool __iscsi_target_sk_check_close(struct sock *sk)
473 {
474 	if (sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) {
475 		pr_debug("__iscsi_target_sk_check_close: TCP_CLOSE_WAIT|TCP_CLOSE,"
476 			"returning TRUE\n");
477 		return true;
478 	}
479 	return false;
480 }
481 
482 static bool iscsi_target_sk_check_close(struct iscsi_conn *conn)
483 {
484 	bool state = false;
485 
486 	if (conn->sock) {
487 		struct sock *sk = conn->sock->sk;
488 
489 		read_lock_bh(&sk->sk_callback_lock);
490 		state = (__iscsi_target_sk_check_close(sk) ||
491 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
492 		read_unlock_bh(&sk->sk_callback_lock);
493 	}
494 	return state;
495 }
496 
497 static bool iscsi_target_sk_check_flag(struct iscsi_conn *conn, unsigned int flag)
498 {
499 	bool state = false;
500 
501 	if (conn->sock) {
502 		struct sock *sk = conn->sock->sk;
503 
504 		read_lock_bh(&sk->sk_callback_lock);
505 		state = test_bit(flag, &conn->login_flags);
506 		read_unlock_bh(&sk->sk_callback_lock);
507 	}
508 	return state;
509 }
510 
511 static bool iscsi_target_sk_check_and_clear(struct iscsi_conn *conn, unsigned int flag)
512 {
513 	bool state = false;
514 
515 	if (conn->sock) {
516 		struct sock *sk = conn->sock->sk;
517 
518 		write_lock_bh(&sk->sk_callback_lock);
519 		state = (__iscsi_target_sk_check_close(sk) ||
520 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
521 		if (!state)
522 			clear_bit(flag, &conn->login_flags);
523 		write_unlock_bh(&sk->sk_callback_lock);
524 	}
525 	return state;
526 }
527 
528 static void iscsi_target_login_drop(struct iscsi_conn *conn, struct iscsi_login *login)
529 {
530 	bool zero_tsih = login->zero_tsih;
531 
532 	iscsi_remove_failed_auth_entry(conn);
533 	iscsi_target_nego_release(conn);
534 	iscsi_target_login_sess_out(conn, zero_tsih, true);
535 }
536 
537 struct conn_timeout {
538 	struct timer_list timer;
539 	struct iscsi_conn *conn;
540 };
541 
542 static void iscsi_target_login_timeout(struct timer_list *t)
543 {
544 	struct conn_timeout *timeout = from_timer(timeout, t, timer);
545 	struct iscsi_conn *conn = timeout->conn;
546 
547 	pr_debug("Entering iscsi_target_login_timeout >>>>>>>>>>>>>>>>>>>\n");
548 
549 	if (conn->login_kworker) {
550 		pr_debug("Sending SIGINT to conn->login_kworker %s/%d\n",
551 			 conn->login_kworker->comm, conn->login_kworker->pid);
552 		send_sig(SIGINT, conn->login_kworker, 1);
553 	}
554 }
555 
556 static void iscsi_target_do_login_rx(struct work_struct *work)
557 {
558 	struct iscsi_conn *conn = container_of(work,
559 				struct iscsi_conn, login_work.work);
560 	struct iscsi_login *login = conn->login;
561 	struct iscsi_np *np = login->np;
562 	struct iscsi_portal_group *tpg = conn->tpg;
563 	struct iscsi_tpg_np *tpg_np = conn->tpg_np;
564 	struct conn_timeout timeout;
565 	int rc, zero_tsih = login->zero_tsih;
566 	bool state;
567 
568 	pr_debug("entering iscsi_target_do_login_rx, conn: %p, %s:%d\n",
569 			conn, current->comm, current->pid);
570 	/*
571 	 * If iscsi_target_do_login_rx() has been invoked by ->sk_data_ready()
572 	 * before initial PDU processing in iscsi_target_start_negotiation()
573 	 * has completed, go ahead and retry until it's cleared.
574 	 *
575 	 * Otherwise if the TCP connection drops while this is occuring,
576 	 * iscsi_target_start_negotiation() will detect the failure, call
577 	 * cancel_delayed_work_sync(&conn->login_work), and cleanup the
578 	 * remaining iscsi connection resources from iscsi_np process context.
579 	 */
580 	if (iscsi_target_sk_check_flag(conn, LOGIN_FLAGS_INITIAL_PDU)) {
581 		schedule_delayed_work(&conn->login_work, msecs_to_jiffies(10));
582 		return;
583 	}
584 
585 	spin_lock(&tpg->tpg_state_lock);
586 	state = (tpg->tpg_state == TPG_STATE_ACTIVE);
587 	spin_unlock(&tpg->tpg_state_lock);
588 
589 	if (!state) {
590 		pr_debug("iscsi_target_do_login_rx: tpg_state != TPG_STATE_ACTIVE\n");
591 		goto err;
592 	}
593 
594 	if (iscsi_target_sk_check_close(conn)) {
595 		pr_debug("iscsi_target_do_login_rx, TCP state CLOSE\n");
596 		goto err;
597 	}
598 
599 	conn->login_kworker = current;
600 	allow_signal(SIGINT);
601 
602 	timeout.conn = conn;
603 	timer_setup_on_stack(&timeout.timer, iscsi_target_login_timeout, 0);
604 	mod_timer(&timeout.timer, jiffies + TA_LOGIN_TIMEOUT * HZ);
605 	pr_debug("Starting login timer for %s/%d\n", current->comm, current->pid);
606 
607 	rc = conn->conn_transport->iscsit_get_login_rx(conn, login);
608 	del_timer_sync(&timeout.timer);
609 	destroy_timer_on_stack(&timeout.timer);
610 	flush_signals(current);
611 	conn->login_kworker = NULL;
612 
613 	if (rc < 0)
614 		goto err;
615 
616 	pr_debug("iscsi_target_do_login_rx after rx_login_io, %p, %s:%d\n",
617 			conn, current->comm, current->pid);
618 
619 	/*
620 	 * LOGIN_FLAGS_READ_ACTIVE is cleared so that sk_data_ready
621 	 * could be triggered again after this.
622 	 *
623 	 * LOGIN_FLAGS_WRITE_ACTIVE is cleared after we successfully
624 	 * process a login PDU, so that sk_state_chage can do login
625 	 * cleanup as needed if the socket is closed. If a delayed work is
626 	 * ongoing (LOGIN_FLAGS_WRITE_ACTIVE or LOGIN_FLAGS_READ_ACTIVE),
627 	 * sk_state_change will leave the cleanup to the delayed work or
628 	 * it will schedule a delayed work to do cleanup.
629 	 */
630 	if (conn->sock) {
631 		struct sock *sk = conn->sock->sk;
632 
633 		write_lock_bh(&sk->sk_callback_lock);
634 		if (!test_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags)) {
635 			clear_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags);
636 			set_bit(LOGIN_FLAGS_WRITE_ACTIVE, &conn->login_flags);
637 		}
638 		write_unlock_bh(&sk->sk_callback_lock);
639 	}
640 
641 	rc = iscsi_target_do_login(conn, login);
642 	if (rc < 0) {
643 		goto err;
644 	} else if (!rc) {
645 		if (iscsi_target_sk_check_and_clear(conn,
646 						    LOGIN_FLAGS_WRITE_ACTIVE))
647 			goto err;
648 	} else if (rc == 1) {
649 		cancel_delayed_work(&conn->login_work);
650 		iscsi_target_nego_release(conn);
651 		iscsi_post_login_handler(np, conn, zero_tsih);
652 		iscsit_deaccess_np(np, tpg, tpg_np);
653 	}
654 	return;
655 
656 err:
657 	iscsi_target_restore_sock_callbacks(conn);
658 	cancel_delayed_work(&conn->login_work);
659 	iscsi_target_login_drop(conn, login);
660 	iscsit_deaccess_np(np, tpg, tpg_np);
661 }
662 
663 static void iscsi_target_sk_state_change(struct sock *sk)
664 {
665 	struct iscsi_conn *conn;
666 	void (*orig_state_change)(struct sock *);
667 	bool state;
668 
669 	pr_debug("Entering iscsi_target_sk_state_change\n");
670 
671 	write_lock_bh(&sk->sk_callback_lock);
672 	conn = sk->sk_user_data;
673 	if (!conn) {
674 		write_unlock_bh(&sk->sk_callback_lock);
675 		return;
676 	}
677 	orig_state_change = conn->orig_state_change;
678 
679 	if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
680 		pr_debug("Got LOGIN_FLAGS_READY=0 sk_state_change conn: %p\n",
681 			 conn);
682 		write_unlock_bh(&sk->sk_callback_lock);
683 		orig_state_change(sk);
684 		return;
685 	}
686 	state = __iscsi_target_sk_check_close(sk);
687 	pr_debug("__iscsi_target_sk_close_change: state: %d\n", state);
688 
689 	if (test_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags) ||
690 	    test_bit(LOGIN_FLAGS_WRITE_ACTIVE, &conn->login_flags)) {
691 		pr_debug("Got LOGIN_FLAGS_{READ|WRITE}_ACTIVE=1"
692 			 " sk_state_change conn: %p\n", conn);
693 		if (state)
694 			set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
695 		write_unlock_bh(&sk->sk_callback_lock);
696 		orig_state_change(sk);
697 		return;
698 	}
699 	if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
700 		pr_debug("Got LOGIN_FLAGS_CLOSED=1 sk_state_change conn: %p\n",
701 			 conn);
702 		write_unlock_bh(&sk->sk_callback_lock);
703 		orig_state_change(sk);
704 		return;
705 	}
706 	/*
707 	 * If the TCP connection has dropped, go ahead and set LOGIN_FLAGS_CLOSED,
708 	 * but only queue conn->login_work -> iscsi_target_do_login_rx()
709 	 * processing if LOGIN_FLAGS_INITIAL_PDU has already been cleared.
710 	 *
711 	 * When iscsi_target_do_login_rx() runs, iscsi_target_sk_check_close()
712 	 * will detect the dropped TCP connection from delayed workqueue context.
713 	 *
714 	 * If LOGIN_FLAGS_INITIAL_PDU is still set, which means the initial
715 	 * iscsi_target_start_negotiation() is running, iscsi_target_do_login()
716 	 * via iscsi_target_sk_check_close() or iscsi_target_start_negotiation()
717 	 * via iscsi_target_sk_check_and_clear() is responsible for detecting the
718 	 * dropped TCP connection in iscsi_np process context, and cleaning up
719 	 * the remaining iscsi connection resources.
720 	 */
721 	if (state) {
722 		pr_debug("iscsi_target_sk_state_change got failed state\n");
723 		set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
724 		state = test_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
725 		write_unlock_bh(&sk->sk_callback_lock);
726 
727 		orig_state_change(sk);
728 
729 		if (!state)
730 			schedule_delayed_work(&conn->login_work, 0);
731 		return;
732 	}
733 	write_unlock_bh(&sk->sk_callback_lock);
734 
735 	orig_state_change(sk);
736 }
737 
738 /*
739  *	NOTE: We check for existing sessions or connections AFTER the initiator
740  *	has been successfully authenticated in order to protect against faked
741  *	ISID/TSIH combinations.
742  */
743 static int iscsi_target_check_for_existing_instances(
744 	struct iscsi_conn *conn,
745 	struct iscsi_login *login)
746 {
747 	if (login->checked_for_existing)
748 		return 0;
749 
750 	login->checked_for_existing = 1;
751 
752 	if (!login->tsih)
753 		return iscsi_check_for_session_reinstatement(conn);
754 	else
755 		return iscsi_login_post_auth_non_zero_tsih(conn, login->cid,
756 				login->initial_exp_statsn);
757 }
758 
759 static int iscsi_target_do_authentication(
760 	struct iscsi_conn *conn,
761 	struct iscsi_login *login)
762 {
763 	int authret;
764 	u32 payload_length;
765 	struct iscsi_param *param;
766 	struct iscsi_login_req *login_req;
767 	struct iscsi_login_rsp *login_rsp;
768 
769 	login_req = (struct iscsi_login_req *) login->req;
770 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
771 	payload_length = ntoh24(login_req->dlength);
772 
773 	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
774 	if (!param)
775 		return -1;
776 
777 	authret = iscsi_handle_authentication(
778 			conn,
779 			login->req_buf,
780 			login->rsp_buf,
781 			payload_length,
782 			&login->rsp_length,
783 			param->value);
784 	switch (authret) {
785 	case 0:
786 		pr_debug("Received OK response"
787 		" from LIO Authentication, continuing.\n");
788 		break;
789 	case 1:
790 		pr_debug("iSCSI security negotiation"
791 			" completed successfully.\n");
792 		login->auth_complete = 1;
793 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
794 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
795 			login_rsp->flags |= (ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
796 					     ISCSI_FLAG_LOGIN_TRANSIT);
797 			login->current_stage = 1;
798 		}
799 		return iscsi_target_check_for_existing_instances(
800 				conn, login);
801 	case 2:
802 		pr_err("Security negotiation"
803 			" failed.\n");
804 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
805 				ISCSI_LOGIN_STATUS_AUTH_FAILED);
806 		return -1;
807 	default:
808 		pr_err("Received unknown error %d from LIO"
809 				" Authentication\n", authret);
810 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
811 				ISCSI_LOGIN_STATUS_TARGET_ERROR);
812 		return -1;
813 	}
814 
815 	return 0;
816 }
817 
818 static int iscsi_target_handle_csg_zero(
819 	struct iscsi_conn *conn,
820 	struct iscsi_login *login)
821 {
822 	int ret;
823 	u32 payload_length;
824 	struct iscsi_param *param;
825 	struct iscsi_login_req *login_req;
826 	struct iscsi_login_rsp *login_rsp;
827 
828 	login_req = (struct iscsi_login_req *) login->req;
829 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
830 	payload_length = ntoh24(login_req->dlength);
831 
832 	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
833 	if (!param)
834 		return -1;
835 
836 	ret = iscsi_decode_text_input(
837 			PHASE_SECURITY|PHASE_DECLARATIVE,
838 			SENDER_INITIATOR|SENDER_RECEIVER,
839 			login->req_buf,
840 			payload_length,
841 			conn);
842 	if (ret < 0)
843 		return -1;
844 
845 	if (ret > 0) {
846 		if (login->auth_complete) {
847 			pr_err("Initiator has already been"
848 				" successfully authenticated, but is still"
849 				" sending %s keys.\n", param->value);
850 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
851 					ISCSI_LOGIN_STATUS_INIT_ERR);
852 			return -1;
853 		}
854 
855 		goto do_auth;
856 	} else if (!payload_length) {
857 		pr_err("Initiator sent zero length security payload,"
858 		       " login failed\n");
859 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
860 				    ISCSI_LOGIN_STATUS_AUTH_FAILED);
861 		return -1;
862 	}
863 
864 	if (login->first_request)
865 		if (iscsi_target_check_first_request(conn, login) < 0)
866 			return -1;
867 
868 	ret = iscsi_encode_text_output(
869 			PHASE_SECURITY|PHASE_DECLARATIVE,
870 			SENDER_TARGET,
871 			login->rsp_buf,
872 			&login->rsp_length,
873 			conn->param_list,
874 			conn->tpg->tpg_attrib.login_keys_workaround);
875 	if (ret < 0)
876 		return -1;
877 
878 	if (!iscsi_check_negotiated_keys(conn->param_list)) {
879 		if (conn->tpg->tpg_attrib.authentication &&
880 		    !strncmp(param->value, NONE, 4)) {
881 			pr_err("Initiator sent AuthMethod=None but"
882 				" Target is enforcing iSCSI Authentication,"
883 					" login failed.\n");
884 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
885 					ISCSI_LOGIN_STATUS_AUTH_FAILED);
886 			return -1;
887 		}
888 
889 		if (conn->tpg->tpg_attrib.authentication &&
890 		    !login->auth_complete)
891 			return 0;
892 
893 		if (strncmp(param->value, NONE, 4) && !login->auth_complete)
894 			return 0;
895 
896 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
897 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
898 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
899 					    ISCSI_FLAG_LOGIN_TRANSIT;
900 			login->current_stage = 1;
901 		}
902 	}
903 
904 	return 0;
905 do_auth:
906 	return iscsi_target_do_authentication(conn, login);
907 }
908 
909 static int iscsi_target_handle_csg_one(struct iscsi_conn *conn, struct iscsi_login *login)
910 {
911 	int ret;
912 	u32 payload_length;
913 	struct iscsi_login_req *login_req;
914 	struct iscsi_login_rsp *login_rsp;
915 
916 	login_req = (struct iscsi_login_req *) login->req;
917 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
918 	payload_length = ntoh24(login_req->dlength);
919 
920 	ret = iscsi_decode_text_input(
921 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
922 			SENDER_INITIATOR|SENDER_RECEIVER,
923 			login->req_buf,
924 			payload_length,
925 			conn);
926 	if (ret < 0) {
927 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
928 				ISCSI_LOGIN_STATUS_INIT_ERR);
929 		return -1;
930 	}
931 
932 	if (login->first_request)
933 		if (iscsi_target_check_first_request(conn, login) < 0)
934 			return -1;
935 
936 	if (iscsi_target_check_for_existing_instances(conn, login) < 0)
937 		return -1;
938 
939 	ret = iscsi_encode_text_output(
940 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
941 			SENDER_TARGET,
942 			login->rsp_buf,
943 			&login->rsp_length,
944 			conn->param_list,
945 			conn->tpg->tpg_attrib.login_keys_workaround);
946 	if (ret < 0) {
947 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
948 				ISCSI_LOGIN_STATUS_INIT_ERR);
949 		return -1;
950 	}
951 
952 	if (!login->auth_complete &&
953 	     conn->tpg->tpg_attrib.authentication) {
954 		pr_err("Initiator is requesting CSG: 1, has not been"
955 			 " successfully authenticated, and the Target is"
956 			" enforcing iSCSI Authentication, login failed.\n");
957 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
958 				ISCSI_LOGIN_STATUS_AUTH_FAILED);
959 		return -1;
960 	}
961 
962 	if (!iscsi_check_negotiated_keys(conn->param_list))
963 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE3) &&
964 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT))
965 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE3 |
966 					    ISCSI_FLAG_LOGIN_TRANSIT;
967 
968 	return 0;
969 }
970 
971 static int iscsi_target_do_login(struct iscsi_conn *conn, struct iscsi_login *login)
972 {
973 	int pdu_count = 0;
974 	struct iscsi_login_req *login_req;
975 	struct iscsi_login_rsp *login_rsp;
976 
977 	login_req = (struct iscsi_login_req *) login->req;
978 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
979 
980 	while (1) {
981 		if (++pdu_count > MAX_LOGIN_PDUS) {
982 			pr_err("MAX_LOGIN_PDUS count reached.\n");
983 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
984 					ISCSI_LOGIN_STATUS_TARGET_ERROR);
985 			return -1;
986 		}
987 
988 		switch (ISCSI_LOGIN_CURRENT_STAGE(login_req->flags)) {
989 		case 0:
990 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK;
991 			if (iscsi_target_handle_csg_zero(conn, login) < 0)
992 				return -1;
993 			break;
994 		case 1:
995 			login_rsp->flags |= ISCSI_FLAG_LOGIN_CURRENT_STAGE1;
996 			if (iscsi_target_handle_csg_one(conn, login) < 0)
997 				return -1;
998 			if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
999 				/*
1000 				 * Check to make sure the TCP connection has not
1001 				 * dropped asynchronously while session reinstatement
1002 				 * was occuring in this kthread context, before
1003 				 * transitioning to full feature phase operation.
1004 				 */
1005 				if (iscsi_target_sk_check_close(conn))
1006 					return -1;
1007 
1008 				login->tsih = conn->sess->tsih;
1009 				login->login_complete = 1;
1010 				iscsi_target_restore_sock_callbacks(conn);
1011 				if (iscsi_target_do_tx_login_io(conn,
1012 						login) < 0)
1013 					return -1;
1014 				return 1;
1015 			}
1016 			break;
1017 		default:
1018 			pr_err("Illegal CSG: %d received from"
1019 				" Initiator, protocol error.\n",
1020 				ISCSI_LOGIN_CURRENT_STAGE(login_req->flags));
1021 			break;
1022 		}
1023 
1024 		if (iscsi_target_do_tx_login_io(conn, login) < 0)
1025 			return -1;
1026 
1027 		if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
1028 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_TRANSIT;
1029 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
1030 		}
1031 		break;
1032 	}
1033 
1034 	return 0;
1035 }
1036 
1037 static void iscsi_initiatorname_tolower(
1038 	char *param_buf)
1039 {
1040 	char *c;
1041 	u32 iqn_size = strlen(param_buf), i;
1042 
1043 	for (i = 0; i < iqn_size; i++) {
1044 		c = &param_buf[i];
1045 		if (!isupper(*c))
1046 			continue;
1047 
1048 		*c = tolower(*c);
1049 	}
1050 }
1051 
1052 /*
1053  * Processes the first Login Request..
1054  */
1055 int iscsi_target_locate_portal(
1056 	struct iscsi_np *np,
1057 	struct iscsi_conn *conn,
1058 	struct iscsi_login *login)
1059 {
1060 	char *i_buf = NULL, *s_buf = NULL, *t_buf = NULL;
1061 	char *tmpbuf, *start = NULL, *end = NULL, *key, *value;
1062 	struct iscsi_session *sess = conn->sess;
1063 	struct iscsi_tiqn *tiqn;
1064 	struct iscsi_tpg_np *tpg_np = NULL;
1065 	struct iscsi_login_req *login_req;
1066 	struct se_node_acl *se_nacl;
1067 	u32 payload_length, queue_depth = 0;
1068 	int sessiontype = 0, ret = 0, tag_num, tag_size;
1069 
1070 	INIT_DELAYED_WORK(&conn->login_work, iscsi_target_do_login_rx);
1071 	iscsi_target_set_sock_callbacks(conn);
1072 
1073 	login->np = np;
1074 
1075 	login_req = (struct iscsi_login_req *) login->req;
1076 	payload_length = ntoh24(login_req->dlength);
1077 
1078 	tmpbuf = kmemdup_nul(login->req_buf, payload_length, GFP_KERNEL);
1079 	if (!tmpbuf) {
1080 		pr_err("Unable to allocate memory for tmpbuf.\n");
1081 		return -1;
1082 	}
1083 
1084 	start = tmpbuf;
1085 	end = (start + payload_length);
1086 
1087 	/*
1088 	 * Locate the initial keys expected from the Initiator node in
1089 	 * the first login request in order to progress with the login phase.
1090 	 */
1091 	while (start < end) {
1092 		if (iscsi_extract_key_value(start, &key, &value) < 0) {
1093 			ret = -1;
1094 			goto out;
1095 		}
1096 
1097 		if (!strncmp(key, "InitiatorName", 13))
1098 			i_buf = value;
1099 		else if (!strncmp(key, "SessionType", 11))
1100 			s_buf = value;
1101 		else if (!strncmp(key, "TargetName", 10))
1102 			t_buf = value;
1103 
1104 		start += strlen(key) + strlen(value) + 2;
1105 	}
1106 	/*
1107 	 * See 5.3.  Login Phase.
1108 	 */
1109 	if (!i_buf) {
1110 		pr_err("InitiatorName key not received"
1111 			" in first login request.\n");
1112 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1113 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1114 		ret = -1;
1115 		goto out;
1116 	}
1117 	/*
1118 	 * Convert the incoming InitiatorName to lowercase following
1119 	 * RFC-3720 3.2.6.1. section c) that says that iSCSI IQNs
1120 	 * are NOT case sensitive.
1121 	 */
1122 	iscsi_initiatorname_tolower(i_buf);
1123 
1124 	if (!s_buf) {
1125 		if (!login->leading_connection)
1126 			goto get_target;
1127 
1128 		pr_err("SessionType key not received"
1129 			" in first login request.\n");
1130 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1131 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1132 		ret = -1;
1133 		goto out;
1134 	}
1135 
1136 	/*
1137 	 * Use default portal group for discovery sessions.
1138 	 */
1139 	sessiontype = strncmp(s_buf, DISCOVERY, 9);
1140 	if (!sessiontype) {
1141 		conn->tpg = iscsit_global->discovery_tpg;
1142 		if (!login->leading_connection)
1143 			goto get_target;
1144 
1145 		sess->sess_ops->SessionType = 1;
1146 		/*
1147 		 * Setup crc32c modules from libcrypto
1148 		 */
1149 		if (iscsi_login_setup_crypto(conn) < 0) {
1150 			pr_err("iscsi_login_setup_crypto() failed\n");
1151 			ret = -1;
1152 			goto out;
1153 		}
1154 		/*
1155 		 * Serialize access across the discovery struct iscsi_portal_group to
1156 		 * process login attempt.
1157 		 */
1158 		if (iscsit_access_np(np, conn->tpg) < 0) {
1159 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1160 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1161 			ret = -1;
1162 			goto out;
1163 		}
1164 		ret = 0;
1165 		goto alloc_tags;
1166 	}
1167 
1168 get_target:
1169 	if (!t_buf) {
1170 		pr_err("TargetName key not received"
1171 			" in first login request while"
1172 			" SessionType=Normal.\n");
1173 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1174 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1175 		ret = -1;
1176 		goto out;
1177 	}
1178 
1179 	/*
1180 	 * Locate Target IQN from Storage Node.
1181 	 */
1182 	tiqn = iscsit_get_tiqn_for_login(t_buf);
1183 	if (!tiqn) {
1184 		pr_err("Unable to locate Target IQN: %s in"
1185 			" Storage Node\n", t_buf);
1186 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1187 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1188 		ret = -1;
1189 		goto out;
1190 	}
1191 	pr_debug("Located Storage Object: %s\n", tiqn->tiqn);
1192 
1193 	/*
1194 	 * Locate Target Portal Group from Storage Node.
1195 	 */
1196 	conn->tpg = iscsit_get_tpg_from_np(tiqn, np, &tpg_np);
1197 	if (!conn->tpg) {
1198 		pr_err("Unable to locate Target Portal Group"
1199 				" on %s\n", tiqn->tiqn);
1200 		iscsit_put_tiqn_for_login(tiqn);
1201 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1202 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1203 		ret = -1;
1204 		goto out;
1205 	}
1206 	conn->tpg_np = tpg_np;
1207 	pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
1208 	/*
1209 	 * Setup crc32c modules from libcrypto
1210 	 */
1211 	if (iscsi_login_setup_crypto(conn) < 0) {
1212 		pr_err("iscsi_login_setup_crypto() failed\n");
1213 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1214 		iscsit_put_tiqn_for_login(tiqn);
1215 		conn->tpg = NULL;
1216 		ret = -1;
1217 		goto out;
1218 	}
1219 	/*
1220 	 * Serialize access across the struct iscsi_portal_group to
1221 	 * process login attempt.
1222 	 */
1223 	if (iscsit_access_np(np, conn->tpg) < 0) {
1224 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1225 		iscsit_put_tiqn_for_login(tiqn);
1226 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1227 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1228 		conn->tpg = NULL;
1229 		ret = -1;
1230 		goto out;
1231 	}
1232 
1233 	/*
1234 	 * conn->sess->node_acl will be set when the referenced
1235 	 * struct iscsi_session is located from received ISID+TSIH in
1236 	 * iscsi_login_non_zero_tsih_s2().
1237 	 */
1238 	if (!login->leading_connection) {
1239 		ret = 0;
1240 		goto out;
1241 	}
1242 
1243 	/*
1244 	 * This value is required in iscsi_login_zero_tsih_s2()
1245 	 */
1246 	sess->sess_ops->SessionType = 0;
1247 
1248 	/*
1249 	 * Locate incoming Initiator IQN reference from Storage Node.
1250 	 */
1251 	sess->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1252 			&conn->tpg->tpg_se_tpg, i_buf);
1253 	if (!sess->se_sess->se_node_acl) {
1254 		pr_err("iSCSI Initiator Node: %s is not authorized to"
1255 			" access iSCSI target portal group: %hu.\n",
1256 				i_buf, conn->tpg->tpgt);
1257 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1258 				ISCSI_LOGIN_STATUS_TGT_FORBIDDEN);
1259 		ret = -1;
1260 		goto out;
1261 	}
1262 	se_nacl = sess->se_sess->se_node_acl;
1263 	queue_depth = se_nacl->queue_depth;
1264 	/*
1265 	 * Setup pre-allocated tags based upon allowed per NodeACL CmdSN
1266 	 * depth for non immediate commands, plus extra tags for immediate
1267 	 * commands.
1268 	 *
1269 	 * Also enforce a ISCSIT_MIN_TAGS to prevent unnecessary contention
1270 	 * in per-cpu-ida tag allocation logic + small queue_depth.
1271 	 */
1272 alloc_tags:
1273 	tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
1274 	tag_num = (tag_num * 2) + ISCSIT_EXTRA_TAGS;
1275 	tag_size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
1276 
1277 	ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);
1278 	if (ret < 0) {
1279 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1280 				    ISCSI_LOGIN_STATUS_NO_RESOURCES);
1281 		ret = -1;
1282 	}
1283 out:
1284 	kfree(tmpbuf);
1285 	return ret;
1286 }
1287 
1288 int iscsi_target_start_negotiation(
1289 	struct iscsi_login *login,
1290 	struct iscsi_conn *conn)
1291 {
1292 	int ret;
1293 
1294 	if (conn->sock) {
1295 		struct sock *sk = conn->sock->sk;
1296 
1297 		write_lock_bh(&sk->sk_callback_lock);
1298 		set_bit(LOGIN_FLAGS_READY, &conn->login_flags);
1299 		set_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
1300 		write_unlock_bh(&sk->sk_callback_lock);
1301 	}
1302 	/*
1303 	 * If iscsi_target_do_login returns zero to signal more PDU
1304 	 * exchanges are required to complete the login, go ahead and
1305 	 * clear LOGIN_FLAGS_INITIAL_PDU but only if the TCP connection
1306 	 * is still active.
1307 	 *
1308 	 * Otherwise if TCP connection dropped asynchronously, go ahead
1309 	 * and perform connection cleanup now.
1310 	 */
1311 	ret = iscsi_target_do_login(conn, login);
1312 	if (!ret && iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_INITIAL_PDU))
1313 		ret = -1;
1314 
1315 	if (ret < 0) {
1316 		cancel_delayed_work_sync(&conn->login_work);
1317 		iscsi_target_restore_sock_callbacks(conn);
1318 		iscsi_remove_failed_auth_entry(conn);
1319 	}
1320 	if (ret != 0)
1321 		iscsi_target_nego_release(conn);
1322 
1323 	return ret;
1324 }
1325 
1326 void iscsi_target_nego_release(struct iscsi_conn *conn)
1327 {
1328 	struct iscsi_login *login = conn->conn_login;
1329 
1330 	if (!login)
1331 		return;
1332 
1333 	kfree(login->req_buf);
1334 	kfree(login->rsp_buf);
1335 	kfree(login);
1336 
1337 	conn->conn_login = NULL;
1338 }
1339