xref: /linux/drivers/target/iscsi/iscsi_target_nego.c (revision 050ab10a645097e47c01cfab3ccf24167e9b266b)
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 struct conn_timeout {
563 	struct timer_list timer;
564 	struct iscsi_conn *conn;
565 };
566 
567 static void iscsi_target_login_timeout(struct timer_list *t)
568 {
569 	struct conn_timeout *timeout = from_timer(timeout, t, timer);
570 	struct iscsi_conn *conn = timeout->conn;
571 
572 	pr_debug("Entering iscsi_target_login_timeout >>>>>>>>>>>>>>>>>>>\n");
573 
574 	if (conn->login_kworker) {
575 		pr_debug("Sending SIGINT to conn->login_kworker %s/%d\n",
576 			 conn->login_kworker->comm, conn->login_kworker->pid);
577 		send_sig(SIGINT, conn->login_kworker, 1);
578 	}
579 }
580 
581 static void iscsi_target_do_login_rx(struct work_struct *work)
582 {
583 	struct iscsi_conn *conn = container_of(work,
584 				struct iscsi_conn, login_work.work);
585 	struct iscsi_login *login = conn->login;
586 	struct iscsi_np *np = login->np;
587 	struct iscsi_portal_group *tpg = conn->tpg;
588 	struct iscsi_tpg_np *tpg_np = conn->tpg_np;
589 	struct conn_timeout timeout;
590 	int rc, zero_tsih = login->zero_tsih;
591 	bool state;
592 
593 	pr_debug("entering iscsi_target_do_login_rx, conn: %p, %s:%d\n",
594 			conn, current->comm, current->pid);
595 	/*
596 	 * If iscsi_target_do_login_rx() has been invoked by ->sk_data_ready()
597 	 * before initial PDU processing in iscsi_target_start_negotiation()
598 	 * has completed, go ahead and retry until it's cleared.
599 	 *
600 	 * Otherwise if the TCP connection drops while this is occuring,
601 	 * iscsi_target_start_negotiation() will detect the failure, call
602 	 * cancel_delayed_work_sync(&conn->login_work), and cleanup the
603 	 * remaining iscsi connection resources from iscsi_np process context.
604 	 */
605 	if (iscsi_target_sk_check_flag(conn, LOGIN_FLAGS_INITIAL_PDU)) {
606 		schedule_delayed_work(&conn->login_work, msecs_to_jiffies(10));
607 		return;
608 	}
609 
610 	spin_lock(&tpg->tpg_state_lock);
611 	state = (tpg->tpg_state == TPG_STATE_ACTIVE);
612 	spin_unlock(&tpg->tpg_state_lock);
613 
614 	if (!state) {
615 		pr_debug("iscsi_target_do_login_rx: tpg_state != TPG_STATE_ACTIVE\n");
616 		goto err;
617 	}
618 
619 	if (iscsi_target_sk_check_close(conn)) {
620 		pr_debug("iscsi_target_do_login_rx, TCP state CLOSE\n");
621 		goto err;
622 	}
623 
624 	conn->login_kworker = current;
625 	allow_signal(SIGINT);
626 
627 	timeout.conn = conn;
628 	timer_setup_on_stack(&timeout.timer, iscsi_target_login_timeout, 0);
629 	mod_timer(&timeout.timer, jiffies + TA_LOGIN_TIMEOUT * HZ);
630 	pr_debug("Starting login timer for %s/%d\n", current->comm, current->pid);
631 
632 	rc = conn->conn_transport->iscsit_get_login_rx(conn, login);
633 	del_timer_sync(&timeout.timer);
634 	destroy_timer_on_stack(&timeout.timer);
635 	flush_signals(current);
636 	conn->login_kworker = NULL;
637 
638 	if (rc < 0)
639 		goto err;
640 
641 	pr_debug("iscsi_target_do_login_rx after rx_login_io, %p, %s:%d\n",
642 			conn, current->comm, current->pid);
643 
644 	rc = iscsi_target_do_login(conn, login);
645 	if (rc < 0) {
646 		goto err;
647 	} else if (!rc) {
648 		if (iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_READ_ACTIVE))
649 			goto err;
650 	} else if (rc == 1) {
651 		iscsi_target_nego_release(conn);
652 		iscsi_post_login_handler(np, conn, zero_tsih);
653 		iscsit_deaccess_np(np, tpg, tpg_np);
654 	}
655 	return;
656 
657 err:
658 	iscsi_target_restore_sock_callbacks(conn);
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 		pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1 sk_state_change"
691 			 " conn: %p\n", conn);
692 		if (state)
693 			set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
694 		write_unlock_bh(&sk->sk_callback_lock);
695 		orig_state_change(sk);
696 		return;
697 	}
698 	if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
699 		pr_debug("Got LOGIN_FLAGS_CLOSED=1 sk_state_change conn: %p\n",
700 			 conn);
701 		write_unlock_bh(&sk->sk_callback_lock);
702 		orig_state_change(sk);
703 		return;
704 	}
705 	/*
706 	 * If the TCP connection has dropped, go ahead and set LOGIN_FLAGS_CLOSED,
707 	 * but only queue conn->login_work -> iscsi_target_do_login_rx()
708 	 * processing if LOGIN_FLAGS_INITIAL_PDU has already been cleared.
709 	 *
710 	 * When iscsi_target_do_login_rx() runs, iscsi_target_sk_check_close()
711 	 * will detect the dropped TCP connection from delayed workqueue context.
712 	 *
713 	 * If LOGIN_FLAGS_INITIAL_PDU is still set, which means the initial
714 	 * iscsi_target_start_negotiation() is running, iscsi_target_do_login()
715 	 * via iscsi_target_sk_check_close() or iscsi_target_start_negotiation()
716 	 * via iscsi_target_sk_check_and_clear() is responsible for detecting the
717 	 * dropped TCP connection in iscsi_np process context, and cleaning up
718 	 * the remaining iscsi connection resources.
719 	 */
720 	if (state) {
721 		pr_debug("iscsi_target_sk_state_change got failed state\n");
722 		set_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags);
723 		state = test_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
724 		write_unlock_bh(&sk->sk_callback_lock);
725 
726 		orig_state_change(sk);
727 
728 		if (!state)
729 			schedule_delayed_work(&conn->login_work, 0);
730 		return;
731 	}
732 	write_unlock_bh(&sk->sk_callback_lock);
733 
734 	orig_state_change(sk);
735 }
736 
737 /*
738  *	NOTE: We check for existing sessions or connections AFTER the initiator
739  *	has been successfully authenticated in order to protect against faked
740  *	ISID/TSIH combinations.
741  */
742 static int iscsi_target_check_for_existing_instances(
743 	struct iscsi_conn *conn,
744 	struct iscsi_login *login)
745 {
746 	if (login->checked_for_existing)
747 		return 0;
748 
749 	login->checked_for_existing = 1;
750 
751 	if (!login->tsih)
752 		return iscsi_check_for_session_reinstatement(conn);
753 	else
754 		return iscsi_login_post_auth_non_zero_tsih(conn, login->cid,
755 				login->initial_exp_statsn);
756 }
757 
758 static int iscsi_target_do_authentication(
759 	struct iscsi_conn *conn,
760 	struct iscsi_login *login)
761 {
762 	int authret;
763 	u32 payload_length;
764 	struct iscsi_param *param;
765 	struct iscsi_login_req *login_req;
766 	struct iscsi_login_rsp *login_rsp;
767 
768 	login_req = (struct iscsi_login_req *) login->req;
769 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
770 	payload_length = ntoh24(login_req->dlength);
771 
772 	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
773 	if (!param)
774 		return -1;
775 
776 	authret = iscsi_handle_authentication(
777 			conn,
778 			login->req_buf,
779 			login->rsp_buf,
780 			payload_length,
781 			&login->rsp_length,
782 			param->value);
783 	switch (authret) {
784 	case 0:
785 		pr_debug("Received OK response"
786 		" from LIO Authentication, continuing.\n");
787 		break;
788 	case 1:
789 		pr_debug("iSCSI security negotiation"
790 			" completed successfully.\n");
791 		login->auth_complete = 1;
792 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
793 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
794 			login_rsp->flags |= (ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
795 					     ISCSI_FLAG_LOGIN_TRANSIT);
796 			login->current_stage = 1;
797 		}
798 		return iscsi_target_check_for_existing_instances(
799 				conn, login);
800 	case 2:
801 		pr_err("Security negotiation"
802 			" failed.\n");
803 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
804 				ISCSI_LOGIN_STATUS_AUTH_FAILED);
805 		return -1;
806 	default:
807 		pr_err("Received unknown error %d from LIO"
808 				" Authentication\n", authret);
809 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
810 				ISCSI_LOGIN_STATUS_TARGET_ERROR);
811 		return -1;
812 	}
813 
814 	return 0;
815 }
816 
817 static int iscsi_target_handle_csg_zero(
818 	struct iscsi_conn *conn,
819 	struct iscsi_login *login)
820 {
821 	int ret;
822 	u32 payload_length;
823 	struct iscsi_param *param;
824 	struct iscsi_login_req *login_req;
825 	struct iscsi_login_rsp *login_rsp;
826 
827 	login_req = (struct iscsi_login_req *) login->req;
828 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
829 	payload_length = ntoh24(login_req->dlength);
830 
831 	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
832 	if (!param)
833 		return -1;
834 
835 	ret = iscsi_decode_text_input(
836 			PHASE_SECURITY|PHASE_DECLARATIVE,
837 			SENDER_INITIATOR|SENDER_RECEIVER,
838 			login->req_buf,
839 			payload_length,
840 			conn);
841 	if (ret < 0)
842 		return -1;
843 
844 	if (ret > 0) {
845 		if (login->auth_complete) {
846 			pr_err("Initiator has already been"
847 				" successfully authenticated, but is still"
848 				" sending %s keys.\n", param->value);
849 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
850 					ISCSI_LOGIN_STATUS_INIT_ERR);
851 			return -1;
852 		}
853 
854 		goto do_auth;
855 	} else if (!payload_length) {
856 		pr_err("Initiator sent zero length security payload,"
857 		       " login failed\n");
858 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
859 				    ISCSI_LOGIN_STATUS_AUTH_FAILED);
860 		return -1;
861 	}
862 
863 	if (login->first_request)
864 		if (iscsi_target_check_first_request(conn, login) < 0)
865 			return -1;
866 
867 	ret = iscsi_encode_text_output(
868 			PHASE_SECURITY|PHASE_DECLARATIVE,
869 			SENDER_TARGET,
870 			login->rsp_buf,
871 			&login->rsp_length,
872 			conn->param_list,
873 			conn->tpg->tpg_attrib.login_keys_workaround);
874 	if (ret < 0)
875 		return -1;
876 
877 	if (!iscsi_check_negotiated_keys(conn->param_list)) {
878 		if (conn->tpg->tpg_attrib.authentication &&
879 		    !strncmp(param->value, NONE, 4)) {
880 			pr_err("Initiator sent AuthMethod=None but"
881 				" Target is enforcing iSCSI Authentication,"
882 					" login failed.\n");
883 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
884 					ISCSI_LOGIN_STATUS_AUTH_FAILED);
885 			return -1;
886 		}
887 
888 		if (conn->tpg->tpg_attrib.authentication &&
889 		    !login->auth_complete)
890 			return 0;
891 
892 		if (strncmp(param->value, NONE, 4) && !login->auth_complete)
893 			return 0;
894 
895 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
896 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
897 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
898 					    ISCSI_FLAG_LOGIN_TRANSIT;
899 			login->current_stage = 1;
900 		}
901 	}
902 
903 	return 0;
904 do_auth:
905 	return iscsi_target_do_authentication(conn, login);
906 }
907 
908 static int iscsi_target_handle_csg_one(struct iscsi_conn *conn, struct iscsi_login *login)
909 {
910 	int ret;
911 	u32 payload_length;
912 	struct iscsi_login_req *login_req;
913 	struct iscsi_login_rsp *login_rsp;
914 
915 	login_req = (struct iscsi_login_req *) login->req;
916 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
917 	payload_length = ntoh24(login_req->dlength);
918 
919 	ret = iscsi_decode_text_input(
920 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
921 			SENDER_INITIATOR|SENDER_RECEIVER,
922 			login->req_buf,
923 			payload_length,
924 			conn);
925 	if (ret < 0) {
926 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
927 				ISCSI_LOGIN_STATUS_INIT_ERR);
928 		return -1;
929 	}
930 
931 	if (login->first_request)
932 		if (iscsi_target_check_first_request(conn, login) < 0)
933 			return -1;
934 
935 	if (iscsi_target_check_for_existing_instances(conn, login) < 0)
936 		return -1;
937 
938 	ret = iscsi_encode_text_output(
939 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
940 			SENDER_TARGET,
941 			login->rsp_buf,
942 			&login->rsp_length,
943 			conn->param_list,
944 			conn->tpg->tpg_attrib.login_keys_workaround);
945 	if (ret < 0) {
946 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
947 				ISCSI_LOGIN_STATUS_INIT_ERR);
948 		return -1;
949 	}
950 
951 	if (!login->auth_complete &&
952 	     conn->tpg->tpg_attrib.authentication) {
953 		pr_err("Initiator is requesting CSG: 1, has not been"
954 			 " successfully authenticated, and the Target is"
955 			" enforcing iSCSI Authentication, login failed.\n");
956 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
957 				ISCSI_LOGIN_STATUS_AUTH_FAILED);
958 		return -1;
959 	}
960 
961 	if (!iscsi_check_negotiated_keys(conn->param_list))
962 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE3) &&
963 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT))
964 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE3 |
965 					    ISCSI_FLAG_LOGIN_TRANSIT;
966 
967 	return 0;
968 }
969 
970 static int iscsi_target_do_login(struct iscsi_conn *conn, struct iscsi_login *login)
971 {
972 	int pdu_count = 0;
973 	struct iscsi_login_req *login_req;
974 	struct iscsi_login_rsp *login_rsp;
975 
976 	login_req = (struct iscsi_login_req *) login->req;
977 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
978 
979 	while (1) {
980 		if (++pdu_count > MAX_LOGIN_PDUS) {
981 			pr_err("MAX_LOGIN_PDUS count reached.\n");
982 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
983 					ISCSI_LOGIN_STATUS_TARGET_ERROR);
984 			return -1;
985 		}
986 
987 		switch (ISCSI_LOGIN_CURRENT_STAGE(login_req->flags)) {
988 		case 0:
989 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK;
990 			if (iscsi_target_handle_csg_zero(conn, login) < 0)
991 				return -1;
992 			break;
993 		case 1:
994 			login_rsp->flags |= ISCSI_FLAG_LOGIN_CURRENT_STAGE1;
995 			if (iscsi_target_handle_csg_one(conn, login) < 0)
996 				return -1;
997 			if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
998 				/*
999 				 * Check to make sure the TCP connection has not
1000 				 * dropped asynchronously while session reinstatement
1001 				 * was occuring in this kthread context, before
1002 				 * transitioning to full feature phase operation.
1003 				 */
1004 				if (iscsi_target_sk_check_close(conn))
1005 					return -1;
1006 
1007 				login->tsih = conn->sess->tsih;
1008 				login->login_complete = 1;
1009 				iscsi_target_restore_sock_callbacks(conn);
1010 				if (iscsi_target_do_tx_login_io(conn,
1011 						login) < 0)
1012 					return -1;
1013 				return 1;
1014 			}
1015 			break;
1016 		default:
1017 			pr_err("Illegal CSG: %d received from"
1018 				" Initiator, protocol error.\n",
1019 				ISCSI_LOGIN_CURRENT_STAGE(login_req->flags));
1020 			break;
1021 		}
1022 
1023 		if (iscsi_target_do_tx_login_io(conn, login) < 0)
1024 			return -1;
1025 
1026 		if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
1027 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_TRANSIT;
1028 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
1029 		}
1030 		break;
1031 	}
1032 
1033 	return 0;
1034 }
1035 
1036 static void iscsi_initiatorname_tolower(
1037 	char *param_buf)
1038 {
1039 	char *c;
1040 	u32 iqn_size = strlen(param_buf), i;
1041 
1042 	for (i = 0; i < iqn_size; i++) {
1043 		c = &param_buf[i];
1044 		if (!isupper(*c))
1045 			continue;
1046 
1047 		*c = tolower(*c);
1048 	}
1049 }
1050 
1051 /*
1052  * Processes the first Login Request..
1053  */
1054 int iscsi_target_locate_portal(
1055 	struct iscsi_np *np,
1056 	struct iscsi_conn *conn,
1057 	struct iscsi_login *login)
1058 {
1059 	char *i_buf = NULL, *s_buf = NULL, *t_buf = NULL;
1060 	char *tmpbuf, *start = NULL, *end = NULL, *key, *value;
1061 	struct iscsi_session *sess = conn->sess;
1062 	struct iscsi_tiqn *tiqn;
1063 	struct iscsi_tpg_np *tpg_np = NULL;
1064 	struct iscsi_login_req *login_req;
1065 	struct se_node_acl *se_nacl;
1066 	u32 payload_length, queue_depth = 0;
1067 	int sessiontype = 0, ret = 0, tag_num, tag_size;
1068 
1069 	INIT_DELAYED_WORK(&conn->login_work, iscsi_target_do_login_rx);
1070 	iscsi_target_set_sock_callbacks(conn);
1071 
1072 	login->np = np;
1073 
1074 	login_req = (struct iscsi_login_req *) login->req;
1075 	payload_length = ntoh24(login_req->dlength);
1076 
1077 	tmpbuf = kzalloc(payload_length + 1, GFP_KERNEL);
1078 	if (!tmpbuf) {
1079 		pr_err("Unable to allocate memory for tmpbuf.\n");
1080 		return -1;
1081 	}
1082 
1083 	memcpy(tmpbuf, login->req_buf, payload_length);
1084 	tmpbuf[payload_length] = '\0';
1085 	start = tmpbuf;
1086 	end = (start + payload_length);
1087 
1088 	/*
1089 	 * Locate the initial keys expected from the Initiator node in
1090 	 * the first login request in order to progress with the login phase.
1091 	 */
1092 	while (start < end) {
1093 		if (iscsi_extract_key_value(start, &key, &value) < 0) {
1094 			ret = -1;
1095 			goto out;
1096 		}
1097 
1098 		if (!strncmp(key, "InitiatorName", 13))
1099 			i_buf = value;
1100 		else if (!strncmp(key, "SessionType", 11))
1101 			s_buf = value;
1102 		else if (!strncmp(key, "TargetName", 10))
1103 			t_buf = value;
1104 
1105 		start += strlen(key) + strlen(value) + 2;
1106 	}
1107 	/*
1108 	 * See 5.3.  Login Phase.
1109 	 */
1110 	if (!i_buf) {
1111 		pr_err("InitiatorName key not received"
1112 			" in first login request.\n");
1113 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1114 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1115 		ret = -1;
1116 		goto out;
1117 	}
1118 	/*
1119 	 * Convert the incoming InitiatorName to lowercase following
1120 	 * RFC-3720 3.2.6.1. section c) that says that iSCSI IQNs
1121 	 * are NOT case sensitive.
1122 	 */
1123 	iscsi_initiatorname_tolower(i_buf);
1124 
1125 	if (!s_buf) {
1126 		if (!login->leading_connection)
1127 			goto get_target;
1128 
1129 		pr_err("SessionType key not received"
1130 			" in first login request.\n");
1131 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1132 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1133 		ret = -1;
1134 		goto out;
1135 	}
1136 
1137 	/*
1138 	 * Use default portal group for discovery sessions.
1139 	 */
1140 	sessiontype = strncmp(s_buf, DISCOVERY, 9);
1141 	if (!sessiontype) {
1142 		conn->tpg = iscsit_global->discovery_tpg;
1143 		if (!login->leading_connection)
1144 			goto get_target;
1145 
1146 		sess->sess_ops->SessionType = 1;
1147 		/*
1148 		 * Setup crc32c modules from libcrypto
1149 		 */
1150 		if (iscsi_login_setup_crypto(conn) < 0) {
1151 			pr_err("iscsi_login_setup_crypto() failed\n");
1152 			ret = -1;
1153 			goto out;
1154 		}
1155 		/*
1156 		 * Serialize access across the discovery struct iscsi_portal_group to
1157 		 * process login attempt.
1158 		 */
1159 		if (iscsit_access_np(np, conn->tpg) < 0) {
1160 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1161 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1162 			ret = -1;
1163 			goto out;
1164 		}
1165 		ret = 0;
1166 		goto alloc_tags;
1167 	}
1168 
1169 get_target:
1170 	if (!t_buf) {
1171 		pr_err("TargetName key not received"
1172 			" in first login request while"
1173 			" SessionType=Normal.\n");
1174 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1175 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1176 		ret = -1;
1177 		goto out;
1178 	}
1179 
1180 	/*
1181 	 * Locate Target IQN from Storage Node.
1182 	 */
1183 	tiqn = iscsit_get_tiqn_for_login(t_buf);
1184 	if (!tiqn) {
1185 		pr_err("Unable to locate Target IQN: %s in"
1186 			" Storage Node\n", t_buf);
1187 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1188 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1189 		ret = -1;
1190 		goto out;
1191 	}
1192 	pr_debug("Located Storage Object: %s\n", tiqn->tiqn);
1193 
1194 	/*
1195 	 * Locate Target Portal Group from Storage Node.
1196 	 */
1197 	conn->tpg = iscsit_get_tpg_from_np(tiqn, np, &tpg_np);
1198 	if (!conn->tpg) {
1199 		pr_err("Unable to locate Target Portal Group"
1200 				" on %s\n", tiqn->tiqn);
1201 		iscsit_put_tiqn_for_login(tiqn);
1202 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1203 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1204 		ret = -1;
1205 		goto out;
1206 	}
1207 	conn->tpg_np = tpg_np;
1208 	pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
1209 	/*
1210 	 * Setup crc32c modules from libcrypto
1211 	 */
1212 	if (iscsi_login_setup_crypto(conn) < 0) {
1213 		pr_err("iscsi_login_setup_crypto() failed\n");
1214 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1215 		iscsit_put_tiqn_for_login(tiqn);
1216 		conn->tpg = NULL;
1217 		ret = -1;
1218 		goto out;
1219 	}
1220 	/*
1221 	 * Serialize access across the struct iscsi_portal_group to
1222 	 * process login attempt.
1223 	 */
1224 	if (iscsit_access_np(np, conn->tpg) < 0) {
1225 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1226 		iscsit_put_tiqn_for_login(tiqn);
1227 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1228 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1229 		conn->tpg = NULL;
1230 		ret = -1;
1231 		goto out;
1232 	}
1233 
1234 	/*
1235 	 * conn->sess->node_acl will be set when the referenced
1236 	 * struct iscsi_session is located from received ISID+TSIH in
1237 	 * iscsi_login_non_zero_tsih_s2().
1238 	 */
1239 	if (!login->leading_connection) {
1240 		ret = 0;
1241 		goto out;
1242 	}
1243 
1244 	/*
1245 	 * This value is required in iscsi_login_zero_tsih_s2()
1246 	 */
1247 	sess->sess_ops->SessionType = 0;
1248 
1249 	/*
1250 	 * Locate incoming Initiator IQN reference from Storage Node.
1251 	 */
1252 	sess->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1253 			&conn->tpg->tpg_se_tpg, i_buf);
1254 	if (!sess->se_sess->se_node_acl) {
1255 		pr_err("iSCSI Initiator Node: %s is not authorized to"
1256 			" access iSCSI target portal group: %hu.\n",
1257 				i_buf, conn->tpg->tpgt);
1258 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1259 				ISCSI_LOGIN_STATUS_TGT_FORBIDDEN);
1260 		ret = -1;
1261 		goto out;
1262 	}
1263 	se_nacl = sess->se_sess->se_node_acl;
1264 	queue_depth = se_nacl->queue_depth;
1265 	/*
1266 	 * Setup pre-allocated tags based upon allowed per NodeACL CmdSN
1267 	 * depth for non immediate commands, plus extra tags for immediate
1268 	 * commands.
1269 	 *
1270 	 * Also enforce a ISCSIT_MIN_TAGS to prevent unnecessary contention
1271 	 * in per-cpu-ida tag allocation logic + small queue_depth.
1272 	 */
1273 alloc_tags:
1274 	tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
1275 	tag_num = (tag_num * 2) + ISCSIT_EXTRA_TAGS;
1276 	tag_size = sizeof(struct iscsi_cmd) + conn->conn_transport->priv_size;
1277 
1278 	ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);
1279 	if (ret < 0) {
1280 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1281 				    ISCSI_LOGIN_STATUS_NO_RESOURCES);
1282 		ret = -1;
1283 	}
1284 out:
1285 	kfree(tmpbuf);
1286 	return ret;
1287 }
1288 
1289 int iscsi_target_start_negotiation(
1290 	struct iscsi_login *login,
1291 	struct iscsi_conn *conn)
1292 {
1293 	int ret;
1294 
1295 	if (conn->sock) {
1296 		struct sock *sk = conn->sock->sk;
1297 
1298 		write_lock_bh(&sk->sk_callback_lock);
1299 		set_bit(LOGIN_FLAGS_READY, &conn->login_flags);
1300 		set_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
1301 		write_unlock_bh(&sk->sk_callback_lock);
1302 	}
1303 	/*
1304 	 * If iscsi_target_do_login returns zero to signal more PDU
1305 	 * exchanges are required to complete the login, go ahead and
1306 	 * clear LOGIN_FLAGS_INITIAL_PDU but only if the TCP connection
1307 	 * is still active.
1308 	 *
1309 	 * Otherwise if TCP connection dropped asynchronously, go ahead
1310 	 * and perform connection cleanup now.
1311 	 */
1312 	ret = iscsi_target_do_login(conn, login);
1313 	if (!ret && iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_INITIAL_PDU))
1314 		ret = -1;
1315 
1316 	if (ret < 0) {
1317 		cancel_delayed_work_sync(&conn->login_work);
1318 		iscsi_target_restore_sock_callbacks(conn);
1319 		iscsi_remove_failed_auth_entry(conn);
1320 	}
1321 	if (ret != 0)
1322 		iscsi_target_nego_release(conn);
1323 
1324 	return ret;
1325 }
1326 
1327 void iscsi_target_nego_release(struct iscsi_conn *conn)
1328 {
1329 	struct iscsi_login *login = conn->conn_login;
1330 
1331 	if (!login)
1332 		return;
1333 
1334 	kfree(login->req_buf);
1335 	kfree(login->rsp_buf);
1336 	kfree(login);
1337 
1338 	conn->conn_login = NULL;
1339 }
1340