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 -EINVAL;
66 
67 	ptr = strstr(in_buf, pattern);
68 	if (!ptr)
69 		return -ENOENT;
70 
71 	ptr = strstr(ptr, "=");
72 	if (!ptr)
73 		return -EINVAL;
74 
75 	ptr += 1;
76 	if (*ptr == '0' && (*(ptr+1) == 'x' || *(ptr+1) == 'X')) {
77 		ptr += 2; /* skip 0x */
78 		*type = HEX;
79 	} else if (*ptr == '0' && (*(ptr+1) == 'b' || *(ptr+1) == 'B')) {
80 		ptr += 2; /* skip 0b */
81 		*type = BASE64;
82 	} else
83 		*type = DECIMAL;
84 
85 	len = strlen_semi(ptr);
86 	if (len < 0)
87 		return -EINVAL;
88 
89 	if (len >= max_length) {
90 		pr_err("Length of input: %d exceeds max_length:"
91 			" %d\n", len, max_length);
92 		return -EINVAL;
93 	}
94 	memcpy(out_buf, ptr, len);
95 	out_buf[len] = '\0';
96 
97 	return 0;
98 }
99 
100 static struct iscsi_node_auth *iscsi_get_node_auth(struct iscsit_conn *conn)
101 {
102 	struct iscsi_portal_group *tpg;
103 	struct iscsi_node_acl *nacl;
104 	struct se_node_acl *se_nacl;
105 
106 	if (conn->sess->sess_ops->SessionType)
107 		return &iscsit_global->discovery_acl.node_auth;
108 
109 	se_nacl = conn->sess->se_sess->se_node_acl;
110 	if (!se_nacl) {
111 		pr_err("Unable to locate struct se_node_acl for CHAP auth\n");
112 		return NULL;
113 	}
114 
115 	if (se_nacl->dynamic_node_acl) {
116 		tpg = to_iscsi_tpg(se_nacl->se_tpg);
117 		return &tpg->tpg_demo_auth;
118 	}
119 
120 	nacl = to_iscsi_nacl(se_nacl);
121 
122 	return &nacl->node_auth;
123 }
124 
125 static u32 iscsi_handle_authentication(
126 	struct iscsit_conn *conn,
127 	char *in_buf,
128 	char *out_buf,
129 	int in_length,
130 	int *out_length,
131 	unsigned char *authtype)
132 {
133 	struct iscsi_node_auth *auth;
134 
135 	auth = iscsi_get_node_auth(conn);
136 	if (!auth)
137 		return -1;
138 
139 	if (strstr("CHAP", authtype))
140 		strcpy(conn->sess->auth_type, "CHAP");
141 	else
142 		strcpy(conn->sess->auth_type, NONE);
143 
144 	if (strstr("None", authtype))
145 		return 1;
146 	else if (strstr("CHAP", authtype))
147 		return chap_main_loop(conn, auth, in_buf, out_buf,
148 				&in_length, out_length);
149 	/* SRP, SPKM1, SPKM2 and KRB5 are unsupported */
150 	return 2;
151 }
152 
153 static void iscsi_remove_failed_auth_entry(struct iscsit_conn *conn)
154 {
155 	kfree(conn->auth_protocol);
156 }
157 
158 int iscsi_target_check_login_request(
159 	struct iscsit_conn *conn,
160 	struct iscsi_login *login)
161 {
162 	int req_csg, req_nsg;
163 	u32 payload_length;
164 	struct iscsi_login_req *login_req;
165 
166 	login_req = (struct iscsi_login_req *) login->req;
167 	payload_length = ntoh24(login_req->dlength);
168 
169 	switch (login_req->opcode & ISCSI_OPCODE_MASK) {
170 	case ISCSI_OP_LOGIN:
171 		break;
172 	default:
173 		pr_err("Received unknown opcode 0x%02x.\n",
174 				login_req->opcode & ISCSI_OPCODE_MASK);
175 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
176 				ISCSI_LOGIN_STATUS_INIT_ERR);
177 		return -1;
178 	}
179 
180 	if ((login_req->flags & ISCSI_FLAG_LOGIN_CONTINUE) &&
181 	    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
182 		pr_err("Login request has both ISCSI_FLAG_LOGIN_CONTINUE"
183 			" and ISCSI_FLAG_LOGIN_TRANSIT set, protocol error.\n");
184 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
185 				ISCSI_LOGIN_STATUS_INIT_ERR);
186 		return -1;
187 	}
188 
189 	req_csg = ISCSI_LOGIN_CURRENT_STAGE(login_req->flags);
190 	req_nsg = ISCSI_LOGIN_NEXT_STAGE(login_req->flags);
191 
192 	if (req_csg != login->current_stage) {
193 		pr_err("Initiator unexpectedly changed login stage"
194 			" from %d to %d, login failed.\n", login->current_stage,
195 			req_csg);
196 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
197 				ISCSI_LOGIN_STATUS_INIT_ERR);
198 		return -1;
199 	}
200 
201 	if ((req_nsg == 2) || (req_csg >= 2) ||
202 	   ((login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT) &&
203 	    (req_nsg <= req_csg))) {
204 		pr_err("Illegal login_req->flags Combination, CSG: %d,"
205 			" NSG: %d, ISCSI_FLAG_LOGIN_TRANSIT: %d.\n", req_csg,
206 			req_nsg, (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT));
207 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
208 				ISCSI_LOGIN_STATUS_INIT_ERR);
209 		return -1;
210 	}
211 
212 	if ((login_req->max_version != login->version_max) ||
213 	    (login_req->min_version != login->version_min)) {
214 		pr_err("Login request changed Version Max/Nin"
215 			" unexpectedly to 0x%02x/0x%02x, protocol error\n",
216 			login_req->max_version, login_req->min_version);
217 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
218 				ISCSI_LOGIN_STATUS_INIT_ERR);
219 		return -1;
220 	}
221 
222 	if (memcmp(login_req->isid, login->isid, 6) != 0) {
223 		pr_err("Login request changed ISID unexpectedly,"
224 				" protocol error.\n");
225 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
226 				ISCSI_LOGIN_STATUS_INIT_ERR);
227 		return -1;
228 	}
229 
230 	if (login_req->itt != login->init_task_tag) {
231 		pr_err("Login request changed ITT unexpectedly to"
232 			" 0x%08x, protocol error.\n", login_req->itt);
233 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
234 				ISCSI_LOGIN_STATUS_INIT_ERR);
235 		return -1;
236 	}
237 
238 	if (payload_length > MAX_KEY_VALUE_PAIRS) {
239 		pr_err("Login request payload exceeds default"
240 			" MaxRecvDataSegmentLength: %u, protocol error.\n",
241 				MAX_KEY_VALUE_PAIRS);
242 		return -1;
243 	}
244 
245 	return 0;
246 }
247 EXPORT_SYMBOL(iscsi_target_check_login_request);
248 
249 static int iscsi_target_check_first_request(
250 	struct iscsit_conn *conn,
251 	struct iscsi_login *login)
252 {
253 	struct iscsi_param *param = NULL;
254 	struct se_node_acl *se_nacl;
255 
256 	login->first_request = 0;
257 
258 	list_for_each_entry(param, &conn->param_list->param_list, p_list) {
259 		if (!strncmp(param->name, SESSIONTYPE, 11)) {
260 			if (!IS_PSTATE_ACCEPTOR(param)) {
261 				pr_err("SessionType key not received"
262 					" in first login request.\n");
263 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
264 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
265 				return -1;
266 			}
267 			if (!strncmp(param->value, DISCOVERY, 9))
268 				return 0;
269 		}
270 
271 		if (!strncmp(param->name, INITIATORNAME, 13)) {
272 			if (!IS_PSTATE_ACCEPTOR(param)) {
273 				if (!login->leading_connection)
274 					continue;
275 
276 				pr_err("InitiatorName key not received"
277 					" in first login request.\n");
278 				iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
279 					ISCSI_LOGIN_STATUS_MISSING_FIELDS);
280 				return -1;
281 			}
282 
283 			/*
284 			 * For non-leading connections, double check that the
285 			 * received InitiatorName matches the existing session's
286 			 * struct iscsi_node_acl.
287 			 */
288 			if (!login->leading_connection) {
289 				se_nacl = conn->sess->se_sess->se_node_acl;
290 				if (!se_nacl) {
291 					pr_err("Unable to locate"
292 						" struct se_node_acl\n");
293 					iscsit_tx_login_rsp(conn,
294 							ISCSI_STATUS_CLS_INITIATOR_ERR,
295 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
296 					return -1;
297 				}
298 
299 				if (strcmp(param->value,
300 						se_nacl->initiatorname)) {
301 					pr_err("Incorrect"
302 						" InitiatorName: %s for this"
303 						" iSCSI Initiator Node.\n",
304 						param->value);
305 					iscsit_tx_login_rsp(conn,
306 							ISCSI_STATUS_CLS_INITIATOR_ERR,
307 							ISCSI_LOGIN_STATUS_TGT_NOT_FOUND);
308 					return -1;
309 				}
310 			}
311 		}
312 	}
313 
314 	return 0;
315 }
316 
317 static int iscsi_target_do_tx_login_io(struct iscsit_conn *conn, struct iscsi_login *login)
318 {
319 	u32 padding = 0;
320 	struct iscsi_login_rsp *login_rsp;
321 
322 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
323 
324 	login_rsp->opcode		= ISCSI_OP_LOGIN_RSP;
325 	hton24(login_rsp->dlength, login->rsp_length);
326 	memcpy(login_rsp->isid, login->isid, 6);
327 	login_rsp->tsih			= cpu_to_be16(login->tsih);
328 	login_rsp->itt			= login->init_task_tag;
329 	login_rsp->statsn		= cpu_to_be32(conn->stat_sn++);
330 	login_rsp->exp_cmdsn		= cpu_to_be32(conn->sess->exp_cmd_sn);
331 	login_rsp->max_cmdsn		= cpu_to_be32((u32) atomic_read(&conn->sess->max_cmd_sn));
332 
333 	pr_debug("Sending Login Response, Flags: 0x%02x, ITT: 0x%08x,"
334 		" ExpCmdSN; 0x%08x, MaxCmdSN: 0x%08x, StatSN: 0x%08x, Length:"
335 		" %u\n", login_rsp->flags, (__force u32)login_rsp->itt,
336 		ntohl(login_rsp->exp_cmdsn), ntohl(login_rsp->max_cmdsn),
337 		ntohl(login_rsp->statsn), login->rsp_length);
338 
339 	padding = ((-login->rsp_length) & 3);
340 	/*
341 	 * Before sending the last login response containing the transition
342 	 * bit for full-feature-phase, go ahead and start up TX/RX threads
343 	 * now to avoid potential resource allocation failures after the
344 	 * final login response has been sent.
345 	 */
346 	if (login->login_complete) {
347 		int rc = iscsit_start_kthreads(conn);
348 		if (rc) {
349 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
350 					    ISCSI_LOGIN_STATUS_NO_RESOURCES);
351 			return -1;
352 		}
353 	}
354 
355 	if (conn->conn_transport->iscsit_put_login_tx(conn, login,
356 					login->rsp_length + padding) < 0)
357 		goto err;
358 
359 	login->rsp_length		= 0;
360 
361 	return 0;
362 
363 err:
364 	if (login->login_complete) {
365 		if (conn->rx_thread && conn->rx_thread_active) {
366 			send_sig(SIGINT, conn->rx_thread, 1);
367 			complete(&conn->rx_login_comp);
368 			kthread_stop(conn->rx_thread);
369 		}
370 		if (conn->tx_thread && conn->tx_thread_active) {
371 			send_sig(SIGINT, conn->tx_thread, 1);
372 			kthread_stop(conn->tx_thread);
373 		}
374 		spin_lock(&iscsit_global->ts_bitmap_lock);
375 		bitmap_release_region(iscsit_global->ts_bitmap, conn->bitmap_id,
376 				      get_order(1));
377 		spin_unlock(&iscsit_global->ts_bitmap_lock);
378 	}
379 	return -1;
380 }
381 
382 static void iscsi_target_sk_data_ready(struct sock *sk)
383 {
384 	struct iscsit_conn *conn = sk->sk_user_data;
385 	bool rc;
386 
387 	pr_debug("Entering iscsi_target_sk_data_ready: conn: %p\n", conn);
388 
389 	write_lock_bh(&sk->sk_callback_lock);
390 	if (!sk->sk_user_data) {
391 		write_unlock_bh(&sk->sk_callback_lock);
392 		return;
393 	}
394 	if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
395 		write_unlock_bh(&sk->sk_callback_lock);
396 		pr_debug("Got LOGIN_FLAGS_READY=0, conn: %p >>>>\n", conn);
397 		return;
398 	}
399 	if (test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags)) {
400 		write_unlock_bh(&sk->sk_callback_lock);
401 		pr_debug("Got LOGIN_FLAGS_CLOSED=1, conn: %p >>>>\n", conn);
402 		return;
403 	}
404 	if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags)) {
405 		write_unlock_bh(&sk->sk_callback_lock);
406 		pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p >>>>\n", conn);
407 		if (iscsi_target_sk_data_ready == conn->orig_data_ready)
408 			return;
409 		conn->orig_data_ready(sk);
410 		return;
411 	}
412 
413 	rc = schedule_delayed_work(&conn->login_work, 0);
414 	if (!rc) {
415 		pr_debug("iscsi_target_sk_data_ready, schedule_delayed_work"
416 			 " got false\n");
417 	}
418 	write_unlock_bh(&sk->sk_callback_lock);
419 }
420 
421 static void iscsi_target_sk_state_change(struct sock *);
422 
423 static void iscsi_target_set_sock_callbacks(struct iscsit_conn *conn)
424 {
425 	struct sock *sk;
426 
427 	if (!conn->sock)
428 		return;
429 
430 	sk = conn->sock->sk;
431 	pr_debug("Entering iscsi_target_set_sock_callbacks: conn: %p\n", conn);
432 
433 	write_lock_bh(&sk->sk_callback_lock);
434 	sk->sk_user_data = conn;
435 	conn->orig_data_ready = sk->sk_data_ready;
436 	conn->orig_state_change = sk->sk_state_change;
437 	sk->sk_data_ready = iscsi_target_sk_data_ready;
438 	sk->sk_state_change = iscsi_target_sk_state_change;
439 	write_unlock_bh(&sk->sk_callback_lock);
440 
441 	sk->sk_sndtimeo = TA_LOGIN_TIMEOUT * HZ;
442 	sk->sk_rcvtimeo = TA_LOGIN_TIMEOUT * HZ;
443 }
444 
445 static void iscsi_target_restore_sock_callbacks(struct iscsit_conn *conn)
446 {
447 	struct sock *sk;
448 
449 	if (!conn->sock)
450 		return;
451 
452 	sk = conn->sock->sk;
453 	pr_debug("Entering iscsi_target_restore_sock_callbacks: conn: %p\n", conn);
454 
455 	write_lock_bh(&sk->sk_callback_lock);
456 	if (!sk->sk_user_data) {
457 		write_unlock_bh(&sk->sk_callback_lock);
458 		return;
459 	}
460 	sk->sk_user_data = NULL;
461 	sk->sk_data_ready = conn->orig_data_ready;
462 	sk->sk_state_change = conn->orig_state_change;
463 	write_unlock_bh(&sk->sk_callback_lock);
464 
465 	sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
466 	sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
467 }
468 
469 static int iscsi_target_do_login(struct iscsit_conn *, struct iscsi_login *);
470 
471 static bool __iscsi_target_sk_check_close(struct sock *sk)
472 {
473 	if (sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) {
474 		pr_debug("__iscsi_target_sk_check_close: TCP_CLOSE_WAIT|TCP_CLOSE,"
475 			"returning TRUE\n");
476 		return true;
477 	}
478 	return false;
479 }
480 
481 static bool iscsi_target_sk_check_close(struct iscsit_conn *conn)
482 {
483 	bool state = false;
484 
485 	if (conn->sock) {
486 		struct sock *sk = conn->sock->sk;
487 
488 		read_lock_bh(&sk->sk_callback_lock);
489 		state = (__iscsi_target_sk_check_close(sk) ||
490 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
491 		read_unlock_bh(&sk->sk_callback_lock);
492 	}
493 	return state;
494 }
495 
496 static bool iscsi_target_sk_check_flag(struct iscsit_conn *conn, unsigned int flag)
497 {
498 	bool state = false;
499 
500 	if (conn->sock) {
501 		struct sock *sk = conn->sock->sk;
502 
503 		read_lock_bh(&sk->sk_callback_lock);
504 		state = test_bit(flag, &conn->login_flags);
505 		read_unlock_bh(&sk->sk_callback_lock);
506 	}
507 	return state;
508 }
509 
510 static bool iscsi_target_sk_check_and_clear(struct iscsit_conn *conn, unsigned int flag)
511 {
512 	bool state = false;
513 
514 	if (conn->sock) {
515 		struct sock *sk = conn->sock->sk;
516 
517 		write_lock_bh(&sk->sk_callback_lock);
518 		state = (__iscsi_target_sk_check_close(sk) ||
519 			 test_bit(LOGIN_FLAGS_CLOSED, &conn->login_flags));
520 		if (!state)
521 			clear_bit(flag, &conn->login_flags);
522 		write_unlock_bh(&sk->sk_callback_lock);
523 	}
524 	return state;
525 }
526 
527 static void iscsi_target_login_drop(struct iscsit_conn *conn, struct iscsi_login *login)
528 {
529 	bool zero_tsih = login->zero_tsih;
530 
531 	iscsi_remove_failed_auth_entry(conn);
532 	iscsi_target_nego_release(conn);
533 	iscsi_target_login_sess_out(conn, zero_tsih, true);
534 }
535 
536 struct conn_timeout {
537 	struct timer_list timer;
538 	struct iscsit_conn *conn;
539 };
540 
541 static void iscsi_target_login_timeout(struct timer_list *t)
542 {
543 	struct conn_timeout *timeout = from_timer(timeout, t, timer);
544 	struct iscsit_conn *conn = timeout->conn;
545 
546 	pr_debug("Entering iscsi_target_login_timeout >>>>>>>>>>>>>>>>>>>\n");
547 
548 	if (conn->login_kworker) {
549 		pr_debug("Sending SIGINT to conn->login_kworker %s/%d\n",
550 			 conn->login_kworker->comm, conn->login_kworker->pid);
551 		send_sig(SIGINT, conn->login_kworker, 1);
552 	}
553 }
554 
555 static void iscsi_target_do_login_rx(struct work_struct *work)
556 {
557 	struct iscsit_conn *conn = container_of(work,
558 				struct iscsit_conn, login_work.work);
559 	struct iscsi_login *login = conn->login;
560 	struct iscsi_np *np = login->np;
561 	struct iscsi_portal_group *tpg = conn->tpg;
562 	struct iscsi_tpg_np *tpg_np = conn->tpg_np;
563 	struct conn_timeout timeout;
564 	int rc, zero_tsih = login->zero_tsih;
565 	bool state;
566 
567 	pr_debug("entering iscsi_target_do_login_rx, conn: %p, %s:%d\n",
568 			conn, current->comm, current->pid);
569 	/*
570 	 * If iscsi_target_do_login_rx() has been invoked by ->sk_data_ready()
571 	 * before initial PDU processing in iscsi_target_start_negotiation()
572 	 * has completed, go ahead and retry until it's cleared.
573 	 *
574 	 * Otherwise if the TCP connection drops while this is occuring,
575 	 * iscsi_target_start_negotiation() will detect the failure, call
576 	 * cancel_delayed_work_sync(&conn->login_work), and cleanup the
577 	 * remaining iscsi connection resources from iscsi_np process context.
578 	 */
579 	if (iscsi_target_sk_check_flag(conn, LOGIN_FLAGS_INITIAL_PDU)) {
580 		schedule_delayed_work(&conn->login_work, msecs_to_jiffies(10));
581 		return;
582 	}
583 
584 	spin_lock(&tpg->tpg_state_lock);
585 	state = (tpg->tpg_state == TPG_STATE_ACTIVE);
586 	spin_unlock(&tpg->tpg_state_lock);
587 
588 	if (!state) {
589 		pr_debug("iscsi_target_do_login_rx: tpg_state != TPG_STATE_ACTIVE\n");
590 		goto err;
591 	}
592 
593 	if (iscsi_target_sk_check_close(conn)) {
594 		pr_debug("iscsi_target_do_login_rx, TCP state CLOSE\n");
595 		goto err;
596 	}
597 
598 	conn->login_kworker = current;
599 	allow_signal(SIGINT);
600 
601 	timeout.conn = conn;
602 	timer_setup_on_stack(&timeout.timer, iscsi_target_login_timeout, 0);
603 	mod_timer(&timeout.timer, jiffies + TA_LOGIN_TIMEOUT * HZ);
604 	pr_debug("Starting login timer for %s/%d\n", current->comm, current->pid);
605 
606 	rc = conn->conn_transport->iscsit_get_login_rx(conn, login);
607 	del_timer_sync(&timeout.timer);
608 	destroy_timer_on_stack(&timeout.timer);
609 	flush_signals(current);
610 	conn->login_kworker = NULL;
611 
612 	if (rc < 0)
613 		goto err;
614 
615 	pr_debug("iscsi_target_do_login_rx after rx_login_io, %p, %s:%d\n",
616 			conn, current->comm, current->pid);
617 
618 	/*
619 	 * LOGIN_FLAGS_READ_ACTIVE is cleared so that sk_data_ready
620 	 * could be triggered again after this.
621 	 *
622 	 * LOGIN_FLAGS_WRITE_ACTIVE is cleared after we successfully
623 	 * process a login PDU, so that sk_state_chage can do login
624 	 * cleanup as needed if the socket is closed. If a delayed work is
625 	 * ongoing (LOGIN_FLAGS_WRITE_ACTIVE or LOGIN_FLAGS_READ_ACTIVE),
626 	 * sk_state_change will leave the cleanup to the delayed work or
627 	 * it will schedule a delayed work to do cleanup.
628 	 */
629 	if (conn->sock) {
630 		struct sock *sk = conn->sock->sk;
631 
632 		write_lock_bh(&sk->sk_callback_lock);
633 		if (!test_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags)) {
634 			clear_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags);
635 			set_bit(LOGIN_FLAGS_WRITE_ACTIVE, &conn->login_flags);
636 		}
637 		write_unlock_bh(&sk->sk_callback_lock);
638 	}
639 
640 	rc = iscsi_target_do_login(conn, login);
641 	if (rc < 0) {
642 		goto err;
643 	} else if (!rc) {
644 		if (iscsi_target_sk_check_and_clear(conn,
645 						    LOGIN_FLAGS_WRITE_ACTIVE))
646 			goto err;
647 	} else if (rc == 1) {
648 		cancel_delayed_work(&conn->login_work);
649 		iscsi_target_nego_release(conn);
650 		iscsi_post_login_handler(np, conn, zero_tsih);
651 		iscsit_deaccess_np(np, tpg, tpg_np);
652 	}
653 	return;
654 
655 err:
656 	iscsi_target_restore_sock_callbacks(conn);
657 	cancel_delayed_work(&conn->login_work);
658 	iscsi_target_login_drop(conn, login);
659 	iscsit_deaccess_np(np, tpg, tpg_np);
660 }
661 
662 static void iscsi_target_sk_state_change(struct sock *sk)
663 {
664 	struct iscsit_conn *conn;
665 	void (*orig_state_change)(struct sock *);
666 	bool state;
667 
668 	pr_debug("Entering iscsi_target_sk_state_change\n");
669 
670 	write_lock_bh(&sk->sk_callback_lock);
671 	conn = sk->sk_user_data;
672 	if (!conn) {
673 		write_unlock_bh(&sk->sk_callback_lock);
674 		return;
675 	}
676 	orig_state_change = conn->orig_state_change;
677 
678 	if (!test_bit(LOGIN_FLAGS_READY, &conn->login_flags)) {
679 		pr_debug("Got LOGIN_FLAGS_READY=0 sk_state_change conn: %p\n",
680 			 conn);
681 		write_unlock_bh(&sk->sk_callback_lock);
682 		orig_state_change(sk);
683 		return;
684 	}
685 	state = __iscsi_target_sk_check_close(sk);
686 	pr_debug("__iscsi_target_sk_close_change: state: %d\n", state);
687 
688 	if (test_bit(LOGIN_FLAGS_READ_ACTIVE, &conn->login_flags) ||
689 	    test_bit(LOGIN_FLAGS_WRITE_ACTIVE, &conn->login_flags)) {
690 		pr_debug("Got LOGIN_FLAGS_{READ|WRITE}_ACTIVE=1"
691 			 " sk_state_change 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 iscsit_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 iscsit_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 bool iscsi_conn_auth_required(struct iscsit_conn *conn)
818 {
819 	struct iscsi_node_acl *nacl;
820 	struct se_node_acl *se_nacl;
821 
822 	if (conn->sess->sess_ops->SessionType) {
823 		/*
824 		 * For SessionType=Discovery
825 		 */
826 		return conn->tpg->tpg_attrib.authentication;
827 	}
828 	/*
829 	 * For SessionType=Normal
830 	 */
831 	se_nacl = conn->sess->se_sess->se_node_acl;
832 	if (!se_nacl) {
833 		pr_debug("Unknown ACL is trying to connect\n");
834 		return true;
835 	}
836 
837 	if (se_nacl->dynamic_node_acl) {
838 		pr_debug("Dynamic ACL %s is trying to connect\n",
839 			 se_nacl->initiatorname);
840 		return conn->tpg->tpg_attrib.authentication;
841 	}
842 
843 	pr_debug("Known ACL %s is trying to connect\n",
844 		 se_nacl->initiatorname);
845 
846 	nacl = to_iscsi_nacl(se_nacl);
847 	if (nacl->node_attrib.authentication == NA_AUTHENTICATION_INHERITED)
848 		return conn->tpg->tpg_attrib.authentication;
849 
850 	return nacl->node_attrib.authentication;
851 }
852 
853 static int iscsi_target_handle_csg_zero(
854 	struct iscsit_conn *conn,
855 	struct iscsi_login *login)
856 {
857 	int ret;
858 	u32 payload_length;
859 	struct iscsi_param *param;
860 	struct iscsi_login_req *login_req;
861 	struct iscsi_login_rsp *login_rsp;
862 
863 	login_req = (struct iscsi_login_req *) login->req;
864 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
865 	payload_length = ntoh24(login_req->dlength);
866 
867 	param = iscsi_find_param_from_key(AUTHMETHOD, conn->param_list);
868 	if (!param)
869 		return -1;
870 
871 	ret = iscsi_decode_text_input(
872 			PHASE_SECURITY|PHASE_DECLARATIVE,
873 			SENDER_INITIATOR|SENDER_RECEIVER,
874 			login->req_buf,
875 			payload_length,
876 			conn);
877 	if (ret < 0)
878 		return -1;
879 
880 	if (ret > 0) {
881 		if (login->auth_complete) {
882 			pr_err("Initiator has already been"
883 				" successfully authenticated, but is still"
884 				" sending %s keys.\n", param->value);
885 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
886 					ISCSI_LOGIN_STATUS_INIT_ERR);
887 			return -1;
888 		}
889 
890 		goto do_auth;
891 	} else if (!payload_length) {
892 		pr_err("Initiator sent zero length security payload,"
893 		       " login failed\n");
894 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
895 				    ISCSI_LOGIN_STATUS_AUTH_FAILED);
896 		return -1;
897 	}
898 
899 	if (login->first_request)
900 		if (iscsi_target_check_first_request(conn, login) < 0)
901 			return -1;
902 
903 	ret = iscsi_encode_text_output(
904 			PHASE_SECURITY|PHASE_DECLARATIVE,
905 			SENDER_TARGET,
906 			login->rsp_buf,
907 			&login->rsp_length,
908 			conn->param_list,
909 			conn->tpg->tpg_attrib.login_keys_workaround);
910 	if (ret < 0)
911 		return -1;
912 
913 	if (!iscsi_check_negotiated_keys(conn->param_list)) {
914 		bool auth_required = iscsi_conn_auth_required(conn);
915 
916 		if (auth_required) {
917 			if (!strncmp(param->value, NONE, 4)) {
918 				pr_err("Initiator sent AuthMethod=None but"
919 				       " Target is enforcing iSCSI Authentication,"
920 				       " login failed.\n");
921 				iscsit_tx_login_rsp(conn,
922 						ISCSI_STATUS_CLS_INITIATOR_ERR,
923 						ISCSI_LOGIN_STATUS_AUTH_FAILED);
924 				return -1;
925 			}
926 
927 			if (!login->auth_complete)
928 				return 0;
929 
930 			if (strncmp(param->value, NONE, 4) &&
931 			    !login->auth_complete)
932 				return 0;
933 		}
934 
935 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE1) &&
936 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT)) {
937 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE1 |
938 					    ISCSI_FLAG_LOGIN_TRANSIT;
939 			login->current_stage = 1;
940 		}
941 	}
942 
943 	return 0;
944 do_auth:
945 	return iscsi_target_do_authentication(conn, login);
946 }
947 
948 static bool iscsi_conn_authenticated(struct iscsit_conn *conn,
949 				     struct iscsi_login *login)
950 {
951 	if (!iscsi_conn_auth_required(conn))
952 		return true;
953 
954 	if (login->auth_complete)
955 		return true;
956 
957 	return false;
958 }
959 
960 static int iscsi_target_handle_csg_one(struct iscsit_conn *conn, struct iscsi_login *login)
961 {
962 	int ret;
963 	u32 payload_length;
964 	struct iscsi_login_req *login_req;
965 	struct iscsi_login_rsp *login_rsp;
966 
967 	login_req = (struct iscsi_login_req *) login->req;
968 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
969 	payload_length = ntoh24(login_req->dlength);
970 
971 	ret = iscsi_decode_text_input(
972 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
973 			SENDER_INITIATOR|SENDER_RECEIVER,
974 			login->req_buf,
975 			payload_length,
976 			conn);
977 	if (ret < 0) {
978 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
979 				ISCSI_LOGIN_STATUS_INIT_ERR);
980 		return -1;
981 	}
982 
983 	if (login->first_request)
984 		if (iscsi_target_check_first_request(conn, login) < 0)
985 			return -1;
986 
987 	if (iscsi_target_check_for_existing_instances(conn, login) < 0)
988 		return -1;
989 
990 	ret = iscsi_encode_text_output(
991 			PHASE_OPERATIONAL|PHASE_DECLARATIVE,
992 			SENDER_TARGET,
993 			login->rsp_buf,
994 			&login->rsp_length,
995 			conn->param_list,
996 			conn->tpg->tpg_attrib.login_keys_workaround);
997 	if (ret < 0) {
998 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
999 				ISCSI_LOGIN_STATUS_INIT_ERR);
1000 		return -1;
1001 	}
1002 
1003 	if (!iscsi_conn_authenticated(conn, login)) {
1004 		pr_err("Initiator is requesting CSG: 1, has not been"
1005 		       " successfully authenticated, and the Target is"
1006 		       " enforcing iSCSI Authentication, login failed.\n");
1007 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1008 				ISCSI_LOGIN_STATUS_AUTH_FAILED);
1009 		return -1;
1010 	}
1011 
1012 	if (!iscsi_check_negotiated_keys(conn->param_list))
1013 		if ((login_req->flags & ISCSI_FLAG_LOGIN_NEXT_STAGE3) &&
1014 		    (login_req->flags & ISCSI_FLAG_LOGIN_TRANSIT))
1015 			login_rsp->flags |= ISCSI_FLAG_LOGIN_NEXT_STAGE3 |
1016 					    ISCSI_FLAG_LOGIN_TRANSIT;
1017 
1018 	return 0;
1019 }
1020 
1021 static int iscsi_target_do_login(struct iscsit_conn *conn, struct iscsi_login *login)
1022 {
1023 	int pdu_count = 0;
1024 	struct iscsi_login_req *login_req;
1025 	struct iscsi_login_rsp *login_rsp;
1026 
1027 	login_req = (struct iscsi_login_req *) login->req;
1028 	login_rsp = (struct iscsi_login_rsp *) login->rsp;
1029 
1030 	while (1) {
1031 		if (++pdu_count > MAX_LOGIN_PDUS) {
1032 			pr_err("MAX_LOGIN_PDUS count reached.\n");
1033 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1034 					ISCSI_LOGIN_STATUS_TARGET_ERROR);
1035 			return -1;
1036 		}
1037 
1038 		switch (ISCSI_LOGIN_CURRENT_STAGE(login_req->flags)) {
1039 		case 0:
1040 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK;
1041 			if (iscsi_target_handle_csg_zero(conn, login) < 0)
1042 				return -1;
1043 			break;
1044 		case 1:
1045 			login_rsp->flags |= ISCSI_FLAG_LOGIN_CURRENT_STAGE1;
1046 			if (iscsi_target_handle_csg_one(conn, login) < 0)
1047 				return -1;
1048 			if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
1049 				/*
1050 				 * Check to make sure the TCP connection has not
1051 				 * dropped asynchronously while session reinstatement
1052 				 * was occuring in this kthread context, before
1053 				 * transitioning to full feature phase operation.
1054 				 */
1055 				if (iscsi_target_sk_check_close(conn))
1056 					return -1;
1057 
1058 				login->tsih = conn->sess->tsih;
1059 				login->login_complete = 1;
1060 				iscsi_target_restore_sock_callbacks(conn);
1061 				if (iscsi_target_do_tx_login_io(conn,
1062 						login) < 0)
1063 					return -1;
1064 				return 1;
1065 			}
1066 			break;
1067 		default:
1068 			pr_err("Illegal CSG: %d received from"
1069 				" Initiator, protocol error.\n",
1070 				ISCSI_LOGIN_CURRENT_STAGE(login_req->flags));
1071 			break;
1072 		}
1073 
1074 		if (iscsi_target_do_tx_login_io(conn, login) < 0)
1075 			return -1;
1076 
1077 		if (login_rsp->flags & ISCSI_FLAG_LOGIN_TRANSIT) {
1078 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_TRANSIT;
1079 			login_rsp->flags &= ~ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
1080 		}
1081 		break;
1082 	}
1083 
1084 	return 0;
1085 }
1086 
1087 static void iscsi_initiatorname_tolower(
1088 	char *param_buf)
1089 {
1090 	char *c;
1091 	u32 iqn_size = strlen(param_buf), i;
1092 
1093 	for (i = 0; i < iqn_size; i++) {
1094 		c = &param_buf[i];
1095 		if (!isupper(*c))
1096 			continue;
1097 
1098 		*c = tolower(*c);
1099 	}
1100 }
1101 
1102 /*
1103  * Processes the first Login Request..
1104  */
1105 int iscsi_target_locate_portal(
1106 	struct iscsi_np *np,
1107 	struct iscsit_conn *conn,
1108 	struct iscsi_login *login)
1109 {
1110 	char *i_buf = NULL, *s_buf = NULL, *t_buf = NULL;
1111 	char *tmpbuf, *start = NULL, *end = NULL, *key, *value;
1112 	struct iscsit_session *sess = conn->sess;
1113 	struct iscsi_tiqn *tiqn;
1114 	struct iscsi_tpg_np *tpg_np = NULL;
1115 	struct iscsi_login_req *login_req;
1116 	struct se_node_acl *se_nacl;
1117 	u32 payload_length, queue_depth = 0;
1118 	int sessiontype = 0, ret = 0, tag_num, tag_size;
1119 
1120 	INIT_DELAYED_WORK(&conn->login_work, iscsi_target_do_login_rx);
1121 	iscsi_target_set_sock_callbacks(conn);
1122 
1123 	login->np = np;
1124 
1125 	login_req = (struct iscsi_login_req *) login->req;
1126 	payload_length = ntoh24(login_req->dlength);
1127 
1128 	tmpbuf = kmemdup_nul(login->req_buf, payload_length, GFP_KERNEL);
1129 	if (!tmpbuf) {
1130 		pr_err("Unable to allocate memory for tmpbuf.\n");
1131 		return -1;
1132 	}
1133 
1134 	start = tmpbuf;
1135 	end = (start + payload_length);
1136 
1137 	/*
1138 	 * Locate the initial keys expected from the Initiator node in
1139 	 * the first login request in order to progress with the login phase.
1140 	 */
1141 	while (start < end) {
1142 		if (iscsi_extract_key_value(start, &key, &value) < 0) {
1143 			ret = -1;
1144 			goto out;
1145 		}
1146 
1147 		if (!strncmp(key, "InitiatorName", 13))
1148 			i_buf = value;
1149 		else if (!strncmp(key, "SessionType", 11))
1150 			s_buf = value;
1151 		else if (!strncmp(key, "TargetName", 10))
1152 			t_buf = value;
1153 
1154 		start += strlen(key) + strlen(value) + 2;
1155 	}
1156 	/*
1157 	 * See 5.3.  Login Phase.
1158 	 */
1159 	if (!i_buf) {
1160 		pr_err("InitiatorName key not received"
1161 			" in first login request.\n");
1162 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1163 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1164 		ret = -1;
1165 		goto out;
1166 	}
1167 	/*
1168 	 * Convert the incoming InitiatorName to lowercase following
1169 	 * RFC-3720 3.2.6.1. section c) that says that iSCSI IQNs
1170 	 * are NOT case sensitive.
1171 	 */
1172 	iscsi_initiatorname_tolower(i_buf);
1173 
1174 	if (!s_buf) {
1175 		if (!login->leading_connection)
1176 			goto get_target;
1177 
1178 		pr_err("SessionType key not received"
1179 			" in first login request.\n");
1180 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1181 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1182 		ret = -1;
1183 		goto out;
1184 	}
1185 
1186 	/*
1187 	 * Use default portal group for discovery sessions.
1188 	 */
1189 	sessiontype = strncmp(s_buf, DISCOVERY, 9);
1190 	if (!sessiontype) {
1191 		conn->tpg = iscsit_global->discovery_tpg;
1192 		if (!login->leading_connection)
1193 			goto get_target;
1194 
1195 		sess->sess_ops->SessionType = 1;
1196 		/*
1197 		 * Setup crc32c modules from libcrypto
1198 		 */
1199 		if (iscsi_login_setup_crypto(conn) < 0) {
1200 			pr_err("iscsi_login_setup_crypto() failed\n");
1201 			ret = -1;
1202 			goto out;
1203 		}
1204 		/*
1205 		 * Serialize access across the discovery struct iscsi_portal_group to
1206 		 * process login attempt.
1207 		 */
1208 		if (iscsit_access_np(np, conn->tpg) < 0) {
1209 			iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1210 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1211 			ret = -1;
1212 			goto out;
1213 		}
1214 		ret = 0;
1215 		goto alloc_tags;
1216 	}
1217 
1218 get_target:
1219 	if (!t_buf) {
1220 		pr_err("TargetName key not received"
1221 			" in first login request while"
1222 			" SessionType=Normal.\n");
1223 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1224 			ISCSI_LOGIN_STATUS_MISSING_FIELDS);
1225 		ret = -1;
1226 		goto out;
1227 	}
1228 
1229 	/*
1230 	 * Locate Target IQN from Storage Node.
1231 	 */
1232 	tiqn = iscsit_get_tiqn_for_login(t_buf);
1233 	if (!tiqn) {
1234 		pr_err("Unable to locate Target IQN: %s in"
1235 			" Storage Node\n", t_buf);
1236 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1237 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1238 		ret = -1;
1239 		goto out;
1240 	}
1241 	pr_debug("Located Storage Object: %s\n", tiqn->tiqn);
1242 
1243 	/*
1244 	 * Locate Target Portal Group from Storage Node.
1245 	 */
1246 	conn->tpg = iscsit_get_tpg_from_np(tiqn, np, &tpg_np);
1247 	if (!conn->tpg) {
1248 		pr_err("Unable to locate Target Portal Group"
1249 				" on %s\n", tiqn->tiqn);
1250 		iscsit_put_tiqn_for_login(tiqn);
1251 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1252 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1253 		ret = -1;
1254 		goto out;
1255 	}
1256 	conn->tpg_np = tpg_np;
1257 	pr_debug("Located Portal Group Object: %hu\n", conn->tpg->tpgt);
1258 	/*
1259 	 * Setup crc32c modules from libcrypto
1260 	 */
1261 	if (iscsi_login_setup_crypto(conn) < 0) {
1262 		pr_err("iscsi_login_setup_crypto() failed\n");
1263 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1264 		iscsit_put_tiqn_for_login(tiqn);
1265 		conn->tpg = NULL;
1266 		ret = -1;
1267 		goto out;
1268 	}
1269 	/*
1270 	 * Serialize access across the struct iscsi_portal_group to
1271 	 * process login attempt.
1272 	 */
1273 	if (iscsit_access_np(np, conn->tpg) < 0) {
1274 		kref_put(&tpg_np->tpg_np_kref, iscsit_login_kref_put);
1275 		iscsit_put_tiqn_for_login(tiqn);
1276 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1277 				ISCSI_LOGIN_STATUS_SVC_UNAVAILABLE);
1278 		conn->tpg = NULL;
1279 		ret = -1;
1280 		goto out;
1281 	}
1282 
1283 	/*
1284 	 * conn->sess->node_acl will be set when the referenced
1285 	 * struct iscsit_session is located from received ISID+TSIH in
1286 	 * iscsi_login_non_zero_tsih_s2().
1287 	 */
1288 	if (!login->leading_connection) {
1289 		ret = 0;
1290 		goto out;
1291 	}
1292 
1293 	/*
1294 	 * This value is required in iscsi_login_zero_tsih_s2()
1295 	 */
1296 	sess->sess_ops->SessionType = 0;
1297 
1298 	/*
1299 	 * Locate incoming Initiator IQN reference from Storage Node.
1300 	 */
1301 	sess->se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1302 			&conn->tpg->tpg_se_tpg, i_buf);
1303 	if (!sess->se_sess->se_node_acl) {
1304 		pr_err("iSCSI Initiator Node: %s is not authorized to"
1305 			" access iSCSI target portal group: %hu.\n",
1306 				i_buf, conn->tpg->tpgt);
1307 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
1308 				ISCSI_LOGIN_STATUS_TGT_FORBIDDEN);
1309 		ret = -1;
1310 		goto out;
1311 	}
1312 	se_nacl = sess->se_sess->se_node_acl;
1313 	queue_depth = se_nacl->queue_depth;
1314 	/*
1315 	 * Setup pre-allocated tags based upon allowed per NodeACL CmdSN
1316 	 * depth for non immediate commands, plus extra tags for immediate
1317 	 * commands.
1318 	 *
1319 	 * Also enforce a ISCSIT_MIN_TAGS to prevent unnecessary contention
1320 	 * in per-cpu-ida tag allocation logic + small queue_depth.
1321 	 */
1322 alloc_tags:
1323 	tag_num = max_t(u32, ISCSIT_MIN_TAGS, queue_depth);
1324 	tag_num = (tag_num * 2) + ISCSIT_EXTRA_TAGS;
1325 	tag_size = sizeof(struct iscsit_cmd) + conn->conn_transport->priv_size;
1326 
1327 	ret = transport_alloc_session_tags(sess->se_sess, tag_num, tag_size);
1328 	if (ret < 0) {
1329 		iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_TARGET_ERR,
1330 				    ISCSI_LOGIN_STATUS_NO_RESOURCES);
1331 		ret = -1;
1332 	}
1333 out:
1334 	kfree(tmpbuf);
1335 	return ret;
1336 }
1337 
1338 int iscsi_target_start_negotiation(
1339 	struct iscsi_login *login,
1340 	struct iscsit_conn *conn)
1341 {
1342 	int ret;
1343 
1344 	if (conn->sock) {
1345 		struct sock *sk = conn->sock->sk;
1346 
1347 		write_lock_bh(&sk->sk_callback_lock);
1348 		set_bit(LOGIN_FLAGS_READY, &conn->login_flags);
1349 		set_bit(LOGIN_FLAGS_INITIAL_PDU, &conn->login_flags);
1350 		write_unlock_bh(&sk->sk_callback_lock);
1351 	}
1352 	/*
1353 	 * If iscsi_target_do_login returns zero to signal more PDU
1354 	 * exchanges are required to complete the login, go ahead and
1355 	 * clear LOGIN_FLAGS_INITIAL_PDU but only if the TCP connection
1356 	 * is still active.
1357 	 *
1358 	 * Otherwise if TCP connection dropped asynchronously, go ahead
1359 	 * and perform connection cleanup now.
1360 	 */
1361 	ret = iscsi_target_do_login(conn, login);
1362 	if (!ret && iscsi_target_sk_check_and_clear(conn, LOGIN_FLAGS_INITIAL_PDU))
1363 		ret = -1;
1364 
1365 	if (ret < 0) {
1366 		cancel_delayed_work_sync(&conn->login_work);
1367 		iscsi_target_restore_sock_callbacks(conn);
1368 		iscsi_remove_failed_auth_entry(conn);
1369 	}
1370 	if (ret != 0)
1371 		iscsi_target_nego_release(conn);
1372 
1373 	return ret;
1374 }
1375 
1376 void iscsi_target_nego_release(struct iscsit_conn *conn)
1377 {
1378 	struct iscsi_login *login = conn->conn_login;
1379 
1380 	if (!login)
1381 		return;
1382 
1383 	kfree(login->req_buf);
1384 	kfree(login->rsp_buf);
1385 	kfree(login);
1386 
1387 	conn->conn_login = NULL;
1388 }
1389