login.c revision 286222
1/*-
2 * Copyright (c) 2012 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Edward Tomasz Napierala under sponsorship
6 * from the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: stable/10/usr.sbin/ctld/login.c 286222 2015-08-03 08:04:31Z trasz $");
33
34#include <assert.h>
35#include <stdbool.h>
36#include <stdint.h>
37#include <stdio.h>
38#include <stdlib.h>
39#include <string.h>
40#include <unistd.h>
41#include <netinet/in.h>
42
43#include "ctld.h"
44#include "iscsi_proto.h"
45
46static void login_send_error(struct pdu *request,
47    char class, char detail);
48
49static void
50login_set_nsg(struct pdu *response, int nsg)
51{
52	struct iscsi_bhs_login_response *bhslr;
53
54	assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
55	    nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
56	    nsg == BHSLR_STAGE_FULL_FEATURE_PHASE);
57
58	bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
59
60	bhslr->bhslr_flags &= 0xFC;
61	bhslr->bhslr_flags |= nsg;
62}
63
64static int
65login_csg(const struct pdu *request)
66{
67	struct iscsi_bhs_login_request *bhslr;
68
69	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
70
71	return ((bhslr->bhslr_flags & 0x0C) >> 2);
72}
73
74static void
75login_set_csg(struct pdu *response, int csg)
76{
77	struct iscsi_bhs_login_response *bhslr;
78
79	assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
80	    csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
81	    csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
82
83	bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
84
85	bhslr->bhslr_flags &= 0xF3;
86	bhslr->bhslr_flags |= csg << 2;
87}
88
89static struct pdu *
90login_receive(struct connection *conn, bool initial)
91{
92	struct pdu *request;
93	struct iscsi_bhs_login_request *bhslr;
94
95	request = pdu_new(conn);
96	pdu_receive(request);
97	if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
98	    ISCSI_BHS_OPCODE_LOGIN_REQUEST) {
99		/*
100		 * The first PDU in session is special - if we receive any PDU
101		 * different than login request, we have to drop the connection
102		 * without sending response ("A target receiving any PDU
103		 * except a Login request before the Login Phase is started MUST
104		 * immediately terminate the connection on which the PDU
105		 * was received.")
106		 */
107		if (initial == false)
108			login_send_error(request, 0x02, 0x0b);
109		log_errx(1, "protocol error: received invalid opcode 0x%x",
110		    request->pdu_bhs->bhs_opcode);
111	}
112	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
113	/*
114	 * XXX: Implement the C flag some day.
115	 */
116	if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) {
117		login_send_error(request, 0x03, 0x00);
118		log_errx(1, "received Login PDU with unsupported \"C\" flag");
119	}
120	if (bhslr->bhslr_version_max != 0x00) {
121		login_send_error(request, 0x02, 0x05);
122		log_errx(1, "received Login PDU with unsupported "
123		    "Version-max 0x%x", bhslr->bhslr_version_max);
124	}
125	if (bhslr->bhslr_version_min != 0x00) {
126		login_send_error(request, 0x02, 0x05);
127		log_errx(1, "received Login PDU with unsupported "
128		    "Version-min 0x%x", bhslr->bhslr_version_min);
129	}
130	if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
131		login_send_error(request, 0x02, 0x05);
132		log_errx(1, "received Login PDU with decreasing CmdSN: "
133		    "was %u, is %u", conn->conn_cmdsn,
134		    ntohl(bhslr->bhslr_cmdsn));
135	}
136	if (initial == false &&
137	    ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
138		login_send_error(request, 0x02, 0x05);
139		log_errx(1, "received Login PDU with wrong ExpStatSN: "
140		    "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
141		    conn->conn_statsn);
142	}
143	conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
144
145	return (request);
146}
147
148static struct pdu *
149login_new_response(struct pdu *request)
150{
151	struct pdu *response;
152	struct connection *conn;
153	struct iscsi_bhs_login_request *bhslr;
154	struct iscsi_bhs_login_response *bhslr2;
155
156	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
157	conn = request->pdu_connection;
158
159	response = pdu_new_response(request);
160	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
161	bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_RESPONSE;
162	login_set_csg(response, BHSLR_STAGE_SECURITY_NEGOTIATION);
163	memcpy(bhslr2->bhslr_isid,
164	    bhslr->bhslr_isid, sizeof(bhslr2->bhslr_isid));
165	bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
166	bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
167	bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
168	bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
169
170	return (response);
171}
172
173static void
174login_send_error(struct pdu *request, char class, char detail)
175{
176	struct pdu *response;
177	struct iscsi_bhs_login_response *bhslr2;
178
179	log_debugx("sending Login Response PDU with failure class 0x%x/0x%x; "
180	    "see next line for reason", class, detail);
181	response = login_new_response(request);
182	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
183	bhslr2->bhslr_status_class = class;
184	bhslr2->bhslr_status_detail = detail;
185
186	pdu_send(response);
187	pdu_delete(response);
188}
189
190static int
191login_list_contains(const char *list, const char *what)
192{
193	char *tofree, *str, *token;
194
195	tofree = str = checked_strdup(list);
196
197	while ((token = strsep(&str, ",")) != NULL) {
198		if (strcmp(token, what) == 0) {
199			free(tofree);
200			return (1);
201		}
202	}
203	free(tofree);
204	return (0);
205}
206
207static int
208login_list_prefers(const char *list,
209    const char *choice1, const char *choice2)
210{
211	char *tofree, *str, *token;
212
213	tofree = str = checked_strdup(list);
214
215	while ((token = strsep(&str, ",")) != NULL) {
216		if (strcmp(token, choice1) == 0) {
217			free(tofree);
218			return (1);
219		}
220		if (strcmp(token, choice2) == 0) {
221			free(tofree);
222			return (2);
223		}
224	}
225	free(tofree);
226	return (-1);
227}
228
229static struct pdu *
230login_receive_chap_a(struct connection *conn)
231{
232	struct pdu *request;
233	struct keys *request_keys;
234	const char *chap_a;
235
236	request = login_receive(conn, false);
237	request_keys = keys_new();
238	keys_load(request_keys, request);
239
240	chap_a = keys_find(request_keys, "CHAP_A");
241	if (chap_a == NULL) {
242		login_send_error(request, 0x02, 0x07);
243		log_errx(1, "received CHAP Login PDU without CHAP_A");
244	}
245	if (login_list_contains(chap_a, "5") == 0) {
246		login_send_error(request, 0x02, 0x01);
247		log_errx(1, "received CHAP Login PDU with unsupported CHAP_A "
248		    "\"%s\"", chap_a);
249	}
250	keys_delete(request_keys);
251
252	return (request);
253}
254
255static void
256login_send_chap_c(struct pdu *request, struct chap *chap)
257{
258	struct pdu *response;
259	struct keys *response_keys;
260	char *chap_c, *chap_i;
261
262	chap_c = chap_get_challenge(chap);
263	chap_i = chap_get_id(chap);
264
265	response = login_new_response(request);
266	response_keys = keys_new();
267	keys_add(response_keys, "CHAP_A", "5");
268	keys_add(response_keys, "CHAP_I", chap_i);
269	keys_add(response_keys, "CHAP_C", chap_c);
270	free(chap_i);
271	free(chap_c);
272	keys_save(response_keys, response);
273	pdu_send(response);
274	pdu_delete(response);
275	keys_delete(response_keys);
276}
277
278static struct pdu *
279login_receive_chap_r(struct connection *conn, struct auth_group *ag,
280    struct chap *chap, const struct auth **authp)
281{
282	struct pdu *request;
283	struct keys *request_keys;
284	const char *chap_n, *chap_r;
285	const struct auth *auth;
286	int error;
287
288	request = login_receive(conn, false);
289	request_keys = keys_new();
290	keys_load(request_keys, request);
291
292	chap_n = keys_find(request_keys, "CHAP_N");
293	if (chap_n == NULL) {
294		login_send_error(request, 0x02, 0x07);
295		log_errx(1, "received CHAP Login PDU without CHAP_N");
296	}
297	chap_r = keys_find(request_keys, "CHAP_R");
298	if (chap_r == NULL) {
299		login_send_error(request, 0x02, 0x07);
300		log_errx(1, "received CHAP Login PDU without CHAP_R");
301	}
302	error = chap_receive(chap, chap_r);
303	if (error != 0) {
304		login_send_error(request, 0x02, 0x07);
305		log_errx(1, "received CHAP Login PDU with malformed CHAP_R");
306	}
307
308	/*
309	 * Verify the response.
310	 */
311	assert(ag->ag_type == AG_TYPE_CHAP ||
312	    ag->ag_type == AG_TYPE_CHAP_MUTUAL);
313	auth = auth_find(ag, chap_n);
314	if (auth == NULL) {
315		login_send_error(request, 0x02, 0x01);
316		log_errx(1, "received CHAP Login with invalid user \"%s\"",
317		    chap_n);
318	}
319
320	assert(auth->a_secret != NULL);
321	assert(strlen(auth->a_secret) > 0);
322
323	error = chap_authenticate(chap, auth->a_secret);
324	if (error != 0) {
325		login_send_error(request, 0x02, 0x01);
326		log_errx(1, "CHAP authentication failed for user \"%s\"",
327		    auth->a_user);
328	}
329
330	keys_delete(request_keys);
331
332	*authp = auth;
333	return (request);
334}
335
336static void
337login_send_chap_success(struct pdu *request,
338    const struct auth *auth)
339{
340	struct pdu *response;
341	struct keys *request_keys, *response_keys;
342	struct iscsi_bhs_login_response *bhslr2;
343	struct rchap *rchap;
344	const char *chap_i, *chap_c;
345	char *chap_r;
346	int error;
347
348	response = login_new_response(request);
349	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
350	bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
351	login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
352
353	/*
354	 * Actually, one more thing: mutual authentication.
355	 */
356	request_keys = keys_new();
357	keys_load(request_keys, request);
358	chap_i = keys_find(request_keys, "CHAP_I");
359	chap_c = keys_find(request_keys, "CHAP_C");
360	if (chap_i != NULL || chap_c != NULL) {
361		if (chap_i == NULL) {
362			login_send_error(request, 0x02, 0x07);
363			log_errx(1, "initiator requested target "
364			    "authentication, but didn't send CHAP_I");
365		}
366		if (chap_c == NULL) {
367			login_send_error(request, 0x02, 0x07);
368			log_errx(1, "initiator requested target "
369			    "authentication, but didn't send CHAP_C");
370		}
371		if (auth->a_auth_group->ag_type != AG_TYPE_CHAP_MUTUAL) {
372			login_send_error(request, 0x02, 0x01);
373			log_errx(1, "initiator requests target authentication "
374			    "for user \"%s\", but mutual user/secret "
375			    "is not set", auth->a_user);
376		}
377
378		log_debugx("performing mutual authentication as user \"%s\"",
379		    auth->a_mutual_user);
380
381		rchap = rchap_new(auth->a_mutual_secret);
382		error = rchap_receive(rchap, chap_i, chap_c);
383		if (error != 0) {
384			login_send_error(request, 0x02, 0x07);
385			log_errx(1, "received CHAP Login PDU with malformed "
386			    "CHAP_I or CHAP_C");
387		}
388		chap_r = rchap_get_response(rchap);
389		rchap_delete(rchap);
390		response_keys = keys_new();
391		keys_add(response_keys, "CHAP_N", auth->a_mutual_user);
392		keys_add(response_keys, "CHAP_R", chap_r);
393		free(chap_r);
394		keys_save(response_keys, response);
395		keys_delete(response_keys);
396	} else {
397		log_debugx("initiator did not request target authentication");
398	}
399
400	keys_delete(request_keys);
401	pdu_send(response);
402	pdu_delete(response);
403}
404
405static void
406login_chap(struct connection *conn, struct auth_group *ag)
407{
408	const struct auth *auth;
409	struct chap *chap;
410	struct pdu *request;
411
412	/*
413	 * Receive CHAP_A PDU.
414	 */
415	log_debugx("beginning CHAP authentication; waiting for CHAP_A");
416	request = login_receive_chap_a(conn);
417
418	/*
419	 * Generate the challenge.
420	 */
421	chap = chap_new();
422
423	/*
424	 * Send the challenge.
425	 */
426	log_debugx("sending CHAP_C, binary challenge size is %zd bytes",
427	    sizeof(chap->chap_challenge));
428	login_send_chap_c(request, chap);
429	pdu_delete(request);
430
431	/*
432	 * Receive CHAP_N/CHAP_R PDU and authenticate.
433	 */
434	log_debugx("waiting for CHAP_N/CHAP_R");
435	request = login_receive_chap_r(conn, ag, chap, &auth);
436
437	/*
438	 * Yay, authentication succeeded!
439	 */
440	log_debugx("authentication succeeded for user \"%s\"; "
441	    "transitioning to Negotiation Phase", auth->a_user);
442	login_send_chap_success(request, auth);
443	pdu_delete(request);
444
445	/*
446	 * Leave username and CHAP information for discovery().
447	 */
448	conn->conn_user = auth->a_user;
449	conn->conn_chap = chap;
450}
451
452static void
453login_negotiate_key(struct pdu *request, const char *name,
454    const char *value, bool skipped_security, struct keys *response_keys)
455{
456	int which, tmp;
457	struct connection *conn;
458
459	conn = request->pdu_connection;
460
461	if (strcmp(name, "InitiatorName") == 0) {
462		if (!skipped_security)
463			log_errx(1, "initiator resent InitiatorName");
464	} else if (strcmp(name, "SessionType") == 0) {
465		if (!skipped_security)
466			log_errx(1, "initiator resent SessionType");
467	} else if (strcmp(name, "TargetName") == 0) {
468		if (!skipped_security)
469			log_errx(1, "initiator resent TargetName");
470	} else if (strcmp(name, "InitiatorAlias") == 0) {
471		if (conn->conn_initiator_alias != NULL)
472			free(conn->conn_initiator_alias);
473		conn->conn_initiator_alias = checked_strdup(value);
474	} else if (strcmp(value, "Irrelevant") == 0) {
475		/* Ignore. */
476	} else if (strcmp(name, "HeaderDigest") == 0) {
477		/*
478		 * We don't handle digests for discovery sessions.
479		 */
480		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
481			log_debugx("discovery session; digests disabled");
482			keys_add(response_keys, name, "None");
483			return;
484		}
485
486		which = login_list_prefers(value, "CRC32C", "None");
487		switch (which) {
488		case 1:
489			log_debugx("initiator prefers CRC32C "
490			    "for header digest; we'll use it");
491			conn->conn_header_digest = CONN_DIGEST_CRC32C;
492			keys_add(response_keys, name, "CRC32C");
493			break;
494		case 2:
495			log_debugx("initiator prefers not to do "
496			    "header digest; we'll comply");
497			keys_add(response_keys, name, "None");
498			break;
499		default:
500			log_warnx("initiator sent unrecognized "
501			    "HeaderDigest value \"%s\"; will use None", value);
502			keys_add(response_keys, name, "None");
503			break;
504		}
505	} else if (strcmp(name, "DataDigest") == 0) {
506		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
507			log_debugx("discovery session; digests disabled");
508			keys_add(response_keys, name, "None");
509			return;
510		}
511
512		which = login_list_prefers(value, "CRC32C", "None");
513		switch (which) {
514		case 1:
515			log_debugx("initiator prefers CRC32C "
516			    "for data digest; we'll use it");
517			conn->conn_data_digest = CONN_DIGEST_CRC32C;
518			keys_add(response_keys, name, "CRC32C");
519			break;
520		case 2:
521			log_debugx("initiator prefers not to do "
522			    "data digest; we'll comply");
523			keys_add(response_keys, name, "None");
524			break;
525		default:
526			log_warnx("initiator sent unrecognized "
527			    "DataDigest value \"%s\"; will use None", value);
528			keys_add(response_keys, name, "None");
529			break;
530		}
531	} else if (strcmp(name, "MaxConnections") == 0) {
532		keys_add(response_keys, name, "1");
533	} else if (strcmp(name, "InitialR2T") == 0) {
534		keys_add(response_keys, name, "Yes");
535	} else if (strcmp(name, "ImmediateData") == 0) {
536		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
537			log_debugx("discovery session; ImmediateData irrelevant");
538			keys_add(response_keys, name, "Irrelevant");
539		} else {
540			if (strcmp(value, "Yes") == 0) {
541				conn->conn_immediate_data = true;
542				keys_add(response_keys, name, "Yes");
543			} else {
544				conn->conn_immediate_data = false;
545				keys_add(response_keys, name, "No");
546			}
547		}
548	} else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
549		tmp = strtoul(value, NULL, 10);
550		if (tmp <= 0) {
551			login_send_error(request, 0x02, 0x00);
552			log_errx(1, "received invalid "
553			    "MaxRecvDataSegmentLength");
554		}
555		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
556			log_debugx("capping MaxRecvDataSegmentLength "
557			    "from %d to %d", tmp, MAX_DATA_SEGMENT_LENGTH);
558			tmp = MAX_DATA_SEGMENT_LENGTH;
559		}
560		conn->conn_max_data_segment_length = tmp;
561		keys_add_int(response_keys, name, MAX_DATA_SEGMENT_LENGTH);
562	} else if (strcmp(name, "MaxBurstLength") == 0) {
563		tmp = strtoul(value, NULL, 10);
564		if (tmp <= 0) {
565			login_send_error(request, 0x02, 0x00);
566			log_errx(1, "received invalid MaxBurstLength");
567		}
568		if (tmp > MAX_BURST_LENGTH) {
569			log_debugx("capping MaxBurstLength from %d to %d",
570			    tmp, MAX_BURST_LENGTH);
571			tmp = MAX_BURST_LENGTH;
572		}
573		conn->conn_max_burst_length = tmp;
574		keys_add(response_keys, name, value);
575	} else if (strcmp(name, "FirstBurstLength") == 0) {
576		tmp = strtoul(value, NULL, 10);
577		if (tmp <= 0) {
578			login_send_error(request, 0x02, 0x00);
579			log_errx(1, "received invalid "
580			    "FirstBurstLength");
581		}
582		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
583			log_debugx("capping FirstBurstLength from %d to %d",
584			    tmp, MAX_DATA_SEGMENT_LENGTH);
585			tmp = MAX_DATA_SEGMENT_LENGTH;
586		}
587		/*
588		 * We don't pass the value to the kernel; it only enforces
589		 * hardcoded limit anyway.
590		 */
591		keys_add_int(response_keys, name, tmp);
592	} else if (strcmp(name, "DefaultTime2Wait") == 0) {
593		keys_add(response_keys, name, value);
594	} else if (strcmp(name, "DefaultTime2Retain") == 0) {
595		keys_add(response_keys, name, "0");
596	} else if (strcmp(name, "MaxOutstandingR2T") == 0) {
597		keys_add(response_keys, name, "1");
598	} else if (strcmp(name, "DataPDUInOrder") == 0) {
599		keys_add(response_keys, name, "Yes");
600	} else if (strcmp(name, "DataSequenceInOrder") == 0) {
601		keys_add(response_keys, name, "Yes");
602	} else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
603		keys_add(response_keys, name, "0");
604	} else if (strcmp(name, "OFMarker") == 0) {
605		keys_add(response_keys, name, "No");
606	} else if (strcmp(name, "IFMarker") == 0) {
607		keys_add(response_keys, name, "No");
608	} else {
609		log_debugx("unknown key \"%s\"; responding "
610		    "with NotUnderstood", name);
611		keys_add(response_keys, name, "NotUnderstood");
612	}
613}
614
615static void
616login_redirect(struct pdu *request, const char *target_address)
617{
618	struct pdu *response;
619	struct iscsi_bhs_login_response *bhslr2;
620	struct keys *response_keys;
621
622	response = login_new_response(request);
623	login_set_csg(response, login_csg(request));
624	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
625	bhslr2->bhslr_status_class = 0x01;
626	bhslr2->bhslr_status_detail = 0x01;
627
628	response_keys = keys_new();
629	keys_add(response_keys, "TargetAddress", target_address);
630
631	keys_save(response_keys, response);
632	pdu_send(response);
633	pdu_delete(response);
634	keys_delete(response_keys);
635}
636
637static bool
638login_portal_redirect(struct connection *conn, struct pdu *request)
639{
640	const struct portal_group *pg;
641
642	pg = conn->conn_portal->p_portal_group;
643	if (pg->pg_redirection == NULL)
644		return (false);
645
646	log_debugx("portal-group \"%s\" configured to redirect to %s",
647	    pg->pg_name, pg->pg_redirection);
648	login_redirect(request, pg->pg_redirection);
649
650	return (true);
651}
652
653static bool
654login_target_redirect(struct connection *conn, struct pdu *request)
655{
656	const char *target_address;
657
658	assert(conn->conn_portal->p_portal_group->pg_redirection == NULL);
659
660	if (conn->conn_target == NULL)
661		return (false);
662
663	target_address = conn->conn_target->t_redirection;
664	if (target_address == NULL)
665		return (false);
666
667	log_debugx("target \"%s\" configured to redirect to %s",
668	  conn->conn_target->t_name, target_address);
669	login_redirect(request, target_address);
670
671	return (true);
672}
673
674static void
675login_negotiate(struct connection *conn, struct pdu *request)
676{
677	struct pdu *response;
678	struct iscsi_bhs_login_response *bhslr2;
679	struct keys *request_keys, *response_keys;
680	int i;
681	bool redirected, skipped_security;
682
683	if (request == NULL) {
684		log_debugx("beginning operational parameter negotiation; "
685		    "waiting for Login PDU");
686		request = login_receive(conn, false);
687		skipped_security = false;
688	} else
689		skipped_security = true;
690
691	/*
692	 * RFC 3720, 10.13.5.  Status-Class and Status-Detail, says
693	 * the redirection SHOULD be accepted by the initiator before
694	 * authentication, but MUST be be accepted afterwards; that's
695	 * why we're doing it here and not earlier.
696	 */
697	redirected = login_target_redirect(conn, request);
698	if (redirected) {
699		log_debugx("initiator redirected; exiting");
700		exit(0);
701	}
702
703	request_keys = keys_new();
704	keys_load(request_keys, request);
705
706	response = login_new_response(request);
707	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
708	bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
709	bhslr2->bhslr_tsih = htons(0xbadd);
710	login_set_csg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
711	login_set_nsg(response, BHSLR_STAGE_FULL_FEATURE_PHASE);
712	response_keys = keys_new();
713
714	if (skipped_security &&
715	    conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
716		if (conn->conn_target->t_alias != NULL)
717			keys_add(response_keys,
718			    "TargetAlias", conn->conn_target->t_alias);
719		keys_add_int(response_keys, "TargetPortalGroupTag",
720		    conn->conn_portal->p_portal_group->pg_tag);
721	}
722
723	for (i = 0; i < KEYS_MAX; i++) {
724		if (request_keys->keys_names[i] == NULL)
725			break;
726
727		login_negotiate_key(request, request_keys->keys_names[i],
728		    request_keys->keys_values[i], skipped_security,
729		    response_keys);
730	}
731
732	log_debugx("operational parameter negotiation done; "
733	    "transitioning to Full Feature Phase");
734
735	keys_save(response_keys, response);
736	pdu_send(response);
737	pdu_delete(response);
738	keys_delete(response_keys);
739	pdu_delete(request);
740	keys_delete(request_keys);
741}
742
743void
744login(struct connection *conn)
745{
746	struct pdu *request, *response;
747	struct iscsi_bhs_login_request *bhslr;
748	struct iscsi_bhs_login_response *bhslr2;
749	struct keys *request_keys, *response_keys;
750	struct auth_group *ag;
751	struct portal_group *pg;
752	const char *initiator_name, *initiator_alias, *session_type,
753	    *target_name, *auth_method;
754	bool redirected;
755
756	/*
757	 * Handle the initial Login Request - figure out required authentication
758	 * method and either transition to the next phase, if no authentication
759	 * is required, or call appropriate authentication code.
760	 */
761	log_debugx("beginning Login Phase; waiting for Login PDU");
762	request = login_receive(conn, true);
763	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
764	if (bhslr->bhslr_tsih != 0) {
765		login_send_error(request, 0x02, 0x0a);
766		log_errx(1, "received Login PDU with non-zero TSIH");
767	}
768
769	pg = conn->conn_portal->p_portal_group;
770
771	memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid,
772	    sizeof(conn->conn_initiator_isid));
773
774	/*
775	 * XXX: Implement the C flag some day.
776	 */
777	request_keys = keys_new();
778	keys_load(request_keys, request);
779
780	assert(conn->conn_initiator_name == NULL);
781	initiator_name = keys_find(request_keys, "InitiatorName");
782	if (initiator_name == NULL) {
783		login_send_error(request, 0x02, 0x07);
784		log_errx(1, "received Login PDU without InitiatorName");
785	}
786	if (valid_iscsi_name(initiator_name) == false) {
787		login_send_error(request, 0x02, 0x00);
788		log_errx(1, "received Login PDU with invalid InitiatorName");
789	}
790	conn->conn_initiator_name = checked_strdup(initiator_name);
791	log_set_peer_name(conn->conn_initiator_name);
792	setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name);
793
794	redirected = login_portal_redirect(conn, request);
795	if (redirected) {
796		log_debugx("initiator redirected; exiting");
797		exit(0);
798	}
799
800	initiator_alias = keys_find(request_keys, "InitiatorAlias");
801	if (initiator_alias != NULL)
802		conn->conn_initiator_alias = checked_strdup(initiator_alias);
803
804	assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE);
805	session_type = keys_find(request_keys, "SessionType");
806	if (session_type != NULL) {
807		if (strcmp(session_type, "Normal") == 0) {
808			conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
809		} else if (strcmp(session_type, "Discovery") == 0) {
810			conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY;
811		} else {
812			login_send_error(request, 0x02, 0x00);
813			log_errx(1, "received Login PDU with invalid "
814			    "SessionType \"%s\"", session_type);
815		}
816	} else
817		conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
818
819	assert(conn->conn_target == NULL);
820	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
821		target_name = keys_find(request_keys, "TargetName");
822		if (target_name == NULL) {
823			login_send_error(request, 0x02, 0x07);
824			log_errx(1, "received Login PDU without TargetName");
825		}
826
827		conn->conn_port = port_find_in_pg(pg, target_name);
828		if (conn->conn_port == NULL) {
829			login_send_error(request, 0x02, 0x03);
830			log_errx(1, "requested target \"%s\" not found",
831			    target_name);
832		}
833		conn->conn_target = conn->conn_port->p_target;
834	}
835
836	/*
837	 * At this point we know what kind of authentication we need.
838	 */
839	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
840		ag = conn->conn_port->p_auth_group;
841		if (ag == NULL)
842			ag = conn->conn_target->t_auth_group;
843		if (ag->ag_name != NULL) {
844			log_debugx("initiator requests to connect "
845			    "to target \"%s\"; auth-group \"%s\"",
846			    conn->conn_target->t_name,
847			    ag->ag_name);
848		} else {
849			log_debugx("initiator requests to connect "
850			    "to target \"%s\"", conn->conn_target->t_name);
851		}
852	} else {
853		assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY);
854		ag = pg->pg_discovery_auth_group;
855		if (ag->ag_name != NULL) {
856			log_debugx("initiator requests "
857			    "discovery session; auth-group \"%s\"", ag->ag_name);
858		} else {
859			log_debugx("initiator requests discovery session");
860		}
861	}
862
863	/*
864	 * Enforce initiator-name and initiator-portal.
865	 */
866	if (auth_name_check(ag, initiator_name) != 0) {
867		login_send_error(request, 0x02, 0x02);
868		log_errx(1, "initiator does not match allowed initiator names");
869	}
870
871	if (auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
872		login_send_error(request, 0x02, 0x02);
873		log_errx(1, "initiator does not match allowed "
874		    "initiator portals");
875	}
876
877	/*
878	 * Let's see if the initiator intends to do any kind of authentication
879	 * at all.
880	 */
881	if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
882		if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
883			login_send_error(request, 0x02, 0x01);
884			log_errx(1, "initiator skipped the authentication, "
885			    "but authentication is required");
886		}
887
888		keys_delete(request_keys);
889
890		log_debugx("initiator skipped the authentication, "
891		    "and we don't need it; proceeding with negotiation");
892		login_negotiate(conn, request);
893		return;
894	}
895
896	if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) {
897		/*
898		 * Initiator might want to to authenticate,
899		 * but we don't need it.
900		 */
901		log_debugx("authentication not required; "
902		    "transitioning to operational parameter negotiation");
903
904		if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0)
905			log_warnx("initiator did not set the \"T\" flag; "
906			    "transitioning anyway");
907
908		response = login_new_response(request);
909		bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
910		bhslr2->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
911		login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
912		response_keys = keys_new();
913		/*
914		 * Required by Linux initiator.
915		 */
916		auth_method = keys_find(request_keys, "AuthMethod");
917		if (auth_method != NULL &&
918		    login_list_contains(auth_method, "None"))
919			keys_add(response_keys, "AuthMethod", "None");
920
921		if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
922			if (conn->conn_target->t_alias != NULL)
923				keys_add(response_keys,
924				    "TargetAlias", conn->conn_target->t_alias);
925			keys_add_int(response_keys,
926			    "TargetPortalGroupTag", pg->pg_tag);
927		}
928		keys_save(response_keys, response);
929		pdu_send(response);
930		pdu_delete(response);
931		keys_delete(response_keys);
932		pdu_delete(request);
933		keys_delete(request_keys);
934
935		login_negotiate(conn, NULL);
936		return;
937	}
938
939	if (ag->ag_type == AG_TYPE_DENY) {
940		login_send_error(request, 0x02, 0x01);
941		log_errx(1, "auth-type is \"deny\"");
942	}
943
944	if (ag->ag_type == AG_TYPE_UNKNOWN) {
945		/*
946		 * This can happen with empty auth-group.
947		 */
948		login_send_error(request, 0x02, 0x01);
949		log_errx(1, "auth-type not set, denying access");
950	}
951
952	log_debugx("CHAP authentication required");
953
954	auth_method = keys_find(request_keys, "AuthMethod");
955	if (auth_method == NULL) {
956		login_send_error(request, 0x02, 0x07);
957		log_errx(1, "received Login PDU without AuthMethod");
958	}
959	/*
960	 * XXX: This should be Reject, not just a login failure (5.3.2).
961	 */
962	if (login_list_contains(auth_method, "CHAP") == 0) {
963		login_send_error(request, 0x02, 0x01);
964		log_errx(1, "initiator requests unsupported AuthMethod \"%s\" "
965		    "instead of \"CHAP\"", auth_method);
966	}
967
968	response = login_new_response(request);
969
970	response_keys = keys_new();
971	keys_add(response_keys, "AuthMethod", "CHAP");
972	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
973		if (conn->conn_target->t_alias != NULL)
974			keys_add(response_keys,
975			    "TargetAlias", conn->conn_target->t_alias);
976		keys_add_int(response_keys,
977		    "TargetPortalGroupTag", pg->pg_tag);
978	}
979	keys_save(response_keys, response);
980
981	pdu_send(response);
982	pdu_delete(response);
983	keys_delete(response_keys);
984	pdu_delete(request);
985	keys_delete(request_keys);
986
987	login_chap(conn, ag);
988
989	login_negotiate(conn, NULL);
990}
991