login.c revision 288753
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 288753 2015-10-05 09:16:01Z mav $");
33
34#include <assert.h>
35#include <stdbool.h>
36#include <stdlib.h>
37#include <string.h>
38#include <unistd.h>
39#include <netinet/in.h>
40
41#include "ctld.h"
42#include "iscsi_proto.h"
43
44static void login_send_error(struct pdu *request,
45    char class, char detail);
46
47static void
48login_set_nsg(struct pdu *response, int nsg)
49{
50	struct iscsi_bhs_login_response *bhslr;
51
52	assert(nsg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
53	    nsg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
54	    nsg == BHSLR_STAGE_FULL_FEATURE_PHASE);
55
56	bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
57
58	bhslr->bhslr_flags &= 0xFC;
59	bhslr->bhslr_flags |= nsg;
60	bhslr->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
61}
62
63static int
64login_csg(const struct pdu *request)
65{
66	struct iscsi_bhs_login_request *bhslr;
67
68	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
69
70	return ((bhslr->bhslr_flags & 0x0C) >> 2);
71}
72
73static void
74login_set_csg(struct pdu *response, int csg)
75{
76	struct iscsi_bhs_login_response *bhslr;
77
78	assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
79	    csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
80	    csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
81
82	bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
83
84	bhslr->bhslr_flags &= 0xF3;
85	bhslr->bhslr_flags |= csg << 2;
86}
87
88static struct pdu *
89login_receive(struct connection *conn, bool initial)
90{
91	struct pdu *request;
92	struct iscsi_bhs_login_request *bhslr;
93
94	request = pdu_new(conn);
95	pdu_receive(request);
96	if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
97	    ISCSI_BHS_OPCODE_LOGIN_REQUEST) {
98		/*
99		 * The first PDU in session is special - if we receive any PDU
100		 * different than login request, we have to drop the connection
101		 * without sending response ("A target receiving any PDU
102		 * except a Login request before the Login Phase is started MUST
103		 * immediately terminate the connection on which the PDU
104		 * was received.")
105		 */
106		if (initial == false)
107			login_send_error(request, 0x02, 0x0b);
108		log_errx(1, "protocol error: received invalid opcode 0x%x",
109		    request->pdu_bhs->bhs_opcode);
110	}
111	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
112	/*
113	 * XXX: Implement the C flag some day.
114	 */
115	if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) {
116		login_send_error(request, 0x03, 0x00);
117		log_errx(1, "received Login PDU with unsupported \"C\" flag");
118	}
119	if (bhslr->bhslr_version_max != 0x00) {
120		login_send_error(request, 0x02, 0x05);
121		log_errx(1, "received Login PDU with unsupported "
122		    "Version-max 0x%x", bhslr->bhslr_version_max);
123	}
124	if (bhslr->bhslr_version_min != 0x00) {
125		login_send_error(request, 0x02, 0x05);
126		log_errx(1, "received Login PDU with unsupported "
127		    "Version-min 0x%x", bhslr->bhslr_version_min);
128	}
129	if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
130		login_send_error(request, 0x02, 0x05);
131		log_errx(1, "received Login PDU with decreasing CmdSN: "
132		    "was %u, is %u", conn->conn_cmdsn,
133		    ntohl(bhslr->bhslr_cmdsn));
134	}
135	if (initial == false &&
136	    ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
137		login_send_error(request, 0x02, 0x05);
138		log_errx(1, "received Login PDU with wrong ExpStatSN: "
139		    "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
140		    conn->conn_statsn);
141	}
142	conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
143
144	return (request);
145}
146
147static struct pdu *
148login_new_response(struct pdu *request)
149{
150	struct pdu *response;
151	struct connection *conn;
152	struct iscsi_bhs_login_request *bhslr;
153	struct iscsi_bhs_login_response *bhslr2;
154
155	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
156	conn = request->pdu_connection;
157
158	response = pdu_new_response(request);
159	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
160	bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_RESPONSE;
161	login_set_csg(response, BHSLR_STAGE_SECURITY_NEGOTIATION);
162	memcpy(bhslr2->bhslr_isid,
163	    bhslr->bhslr_isid, sizeof(bhslr2->bhslr_isid));
164	bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
165	bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
166	bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
167	bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
168
169	return (response);
170}
171
172static void
173login_send_error(struct pdu *request, char class, char detail)
174{
175	struct pdu *response;
176	struct iscsi_bhs_login_response *bhslr2;
177
178	log_debugx("sending Login Response PDU with failure class 0x%x/0x%x; "
179	    "see next line for reason", class, detail);
180	response = login_new_response(request);
181	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
182	bhslr2->bhslr_status_class = class;
183	bhslr2->bhslr_status_detail = detail;
184
185	pdu_send(response);
186	pdu_delete(response);
187}
188
189static int
190login_list_contains(const char *list, const char *what)
191{
192	char *tofree, *str, *token;
193
194	tofree = str = checked_strdup(list);
195
196	while ((token = strsep(&str, ",")) != NULL) {
197		if (strcmp(token, what) == 0) {
198			free(tofree);
199			return (1);
200		}
201	}
202	free(tofree);
203	return (0);
204}
205
206static int
207login_list_prefers(const char *list,
208    const char *choice1, const char *choice2)
209{
210	char *tofree, *str, *token;
211
212	tofree = str = checked_strdup(list);
213
214	while ((token = strsep(&str, ",")) != NULL) {
215		if (strcmp(token, choice1) == 0) {
216			free(tofree);
217			return (1);
218		}
219		if (strcmp(token, choice2) == 0) {
220			free(tofree);
221			return (2);
222		}
223	}
224	free(tofree);
225	return (-1);
226}
227
228static struct pdu *
229login_receive_chap_a(struct connection *conn)
230{
231	struct pdu *request;
232	struct keys *request_keys;
233	const char *chap_a;
234
235	request = login_receive(conn, false);
236	request_keys = keys_new();
237	keys_load(request_keys, request);
238
239	chap_a = keys_find(request_keys, "CHAP_A");
240	if (chap_a == NULL) {
241		login_send_error(request, 0x02, 0x07);
242		log_errx(1, "received CHAP Login PDU without CHAP_A");
243	}
244	if (login_list_contains(chap_a, "5") == 0) {
245		login_send_error(request, 0x02, 0x01);
246		log_errx(1, "received CHAP Login PDU with unsupported CHAP_A "
247		    "\"%s\"", chap_a);
248	}
249	keys_delete(request_keys);
250
251	return (request);
252}
253
254static void
255login_send_chap_c(struct pdu *request, struct chap *chap)
256{
257	struct pdu *response;
258	struct keys *response_keys;
259	char *chap_c, *chap_i;
260
261	chap_c = chap_get_challenge(chap);
262	chap_i = chap_get_id(chap);
263
264	response = login_new_response(request);
265	response_keys = keys_new();
266	keys_add(response_keys, "CHAP_A", "5");
267	keys_add(response_keys, "CHAP_I", chap_i);
268	keys_add(response_keys, "CHAP_C", chap_c);
269	free(chap_i);
270	free(chap_c);
271	keys_save(response_keys, response);
272	pdu_send(response);
273	pdu_delete(response);
274	keys_delete(response_keys);
275}
276
277static struct pdu *
278login_receive_chap_r(struct connection *conn, struct auth_group *ag,
279    struct chap *chap, const struct auth **authp)
280{
281	struct pdu *request;
282	struct keys *request_keys;
283	const char *chap_n, *chap_r;
284	const struct auth *auth;
285	int error;
286
287	request = login_receive(conn, false);
288	request_keys = keys_new();
289	keys_load(request_keys, request);
290
291	chap_n = keys_find(request_keys, "CHAP_N");
292	if (chap_n == NULL) {
293		login_send_error(request, 0x02, 0x07);
294		log_errx(1, "received CHAP Login PDU without CHAP_N");
295	}
296	chap_r = keys_find(request_keys, "CHAP_R");
297	if (chap_r == NULL) {
298		login_send_error(request, 0x02, 0x07);
299		log_errx(1, "received CHAP Login PDU without CHAP_R");
300	}
301	error = chap_receive(chap, chap_r);
302	if (error != 0) {
303		login_send_error(request, 0x02, 0x07);
304		log_errx(1, "received CHAP Login PDU with malformed CHAP_R");
305	}
306
307	/*
308	 * Verify the response.
309	 */
310	assert(ag->ag_type == AG_TYPE_CHAP ||
311	    ag->ag_type == AG_TYPE_CHAP_MUTUAL);
312	auth = auth_find(ag, chap_n);
313	if (auth == NULL) {
314		login_send_error(request, 0x02, 0x01);
315		log_errx(1, "received CHAP Login with invalid user \"%s\"",
316		    chap_n);
317	}
318
319	assert(auth->a_secret != NULL);
320	assert(strlen(auth->a_secret) > 0);
321
322	error = chap_authenticate(chap, auth->a_secret);
323	if (error != 0) {
324		login_send_error(request, 0x02, 0x01);
325		log_errx(1, "CHAP authentication failed for user \"%s\"",
326		    auth->a_user);
327	}
328
329	keys_delete(request_keys);
330
331	*authp = auth;
332	return (request);
333}
334
335static void
336login_send_chap_success(struct pdu *request,
337    const struct auth *auth)
338{
339	struct pdu *response;
340	struct keys *request_keys, *response_keys;
341	struct rchap *rchap;
342	const char *chap_i, *chap_c;
343	char *chap_r;
344	int error;
345
346	response = login_new_response(request);
347	login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
348
349	/*
350	 * Actually, one more thing: mutual authentication.
351	 */
352	request_keys = keys_new();
353	keys_load(request_keys, request);
354	chap_i = keys_find(request_keys, "CHAP_I");
355	chap_c = keys_find(request_keys, "CHAP_C");
356	if (chap_i != NULL || chap_c != NULL) {
357		if (chap_i == NULL) {
358			login_send_error(request, 0x02, 0x07);
359			log_errx(1, "initiator requested target "
360			    "authentication, but didn't send CHAP_I");
361		}
362		if (chap_c == NULL) {
363			login_send_error(request, 0x02, 0x07);
364			log_errx(1, "initiator requested target "
365			    "authentication, but didn't send CHAP_C");
366		}
367		if (auth->a_auth_group->ag_type != AG_TYPE_CHAP_MUTUAL) {
368			login_send_error(request, 0x02, 0x01);
369			log_errx(1, "initiator requests target authentication "
370			    "for user \"%s\", but mutual user/secret "
371			    "is not set", auth->a_user);
372		}
373
374		log_debugx("performing mutual authentication as user \"%s\"",
375		    auth->a_mutual_user);
376
377		rchap = rchap_new(auth->a_mutual_secret);
378		error = rchap_receive(rchap, chap_i, chap_c);
379		if (error != 0) {
380			login_send_error(request, 0x02, 0x07);
381			log_errx(1, "received CHAP Login PDU with malformed "
382			    "CHAP_I or CHAP_C");
383		}
384		chap_r = rchap_get_response(rchap);
385		rchap_delete(rchap);
386		response_keys = keys_new();
387		keys_add(response_keys, "CHAP_N", auth->a_mutual_user);
388		keys_add(response_keys, "CHAP_R", chap_r);
389		free(chap_r);
390		keys_save(response_keys, response);
391		keys_delete(response_keys);
392	} else {
393		log_debugx("initiator did not request target authentication");
394	}
395
396	keys_delete(request_keys);
397	pdu_send(response);
398	pdu_delete(response);
399}
400
401static void
402login_chap(struct connection *conn, struct auth_group *ag)
403{
404	const struct auth *auth;
405	struct chap *chap;
406	struct pdu *request;
407
408	/*
409	 * Receive CHAP_A PDU.
410	 */
411	log_debugx("beginning CHAP authentication; waiting for CHAP_A");
412	request = login_receive_chap_a(conn);
413
414	/*
415	 * Generate the challenge.
416	 */
417	chap = chap_new();
418
419	/*
420	 * Send the challenge.
421	 */
422	log_debugx("sending CHAP_C, binary challenge size is %zd bytes",
423	    sizeof(chap->chap_challenge));
424	login_send_chap_c(request, chap);
425	pdu_delete(request);
426
427	/*
428	 * Receive CHAP_N/CHAP_R PDU and authenticate.
429	 */
430	log_debugx("waiting for CHAP_N/CHAP_R");
431	request = login_receive_chap_r(conn, ag, chap, &auth);
432
433	/*
434	 * Yay, authentication succeeded!
435	 */
436	log_debugx("authentication succeeded for user \"%s\"; "
437	    "transitioning to Negotiation Phase", auth->a_user);
438	login_send_chap_success(request, auth);
439	pdu_delete(request);
440
441	/*
442	 * Leave username and CHAP information for discovery().
443	 */
444	conn->conn_user = auth->a_user;
445	conn->conn_chap = chap;
446}
447
448static void
449login_negotiate_key(struct pdu *request, const char *name,
450    const char *value, bool skipped_security, struct keys *response_keys)
451{
452	int which, tmp;
453	struct connection *conn;
454
455	conn = request->pdu_connection;
456
457	if (strcmp(name, "InitiatorName") == 0) {
458		if (!skipped_security)
459			log_errx(1, "initiator resent InitiatorName");
460	} else if (strcmp(name, "SessionType") == 0) {
461		if (!skipped_security)
462			log_errx(1, "initiator resent SessionType");
463	} else if (strcmp(name, "TargetName") == 0) {
464		if (!skipped_security)
465			log_errx(1, "initiator resent TargetName");
466	} else if (strcmp(name, "InitiatorAlias") == 0) {
467		if (conn->conn_initiator_alias != NULL)
468			free(conn->conn_initiator_alias);
469		conn->conn_initiator_alias = checked_strdup(value);
470	} else if (strcmp(value, "Irrelevant") == 0) {
471		/* Ignore. */
472	} else if (strcmp(name, "HeaderDigest") == 0) {
473		/*
474		 * We don't handle digests for discovery sessions.
475		 */
476		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
477			log_debugx("discovery session; digests disabled");
478			keys_add(response_keys, name, "None");
479			return;
480		}
481
482		which = login_list_prefers(value, "CRC32C", "None");
483		switch (which) {
484		case 1:
485			log_debugx("initiator prefers CRC32C "
486			    "for header digest; we'll use it");
487			conn->conn_header_digest = CONN_DIGEST_CRC32C;
488			keys_add(response_keys, name, "CRC32C");
489			break;
490		case 2:
491			log_debugx("initiator prefers not to do "
492			    "header digest; we'll comply");
493			keys_add(response_keys, name, "None");
494			break;
495		default:
496			log_warnx("initiator sent unrecognized "
497			    "HeaderDigest value \"%s\"; will use None", value);
498			keys_add(response_keys, name, "None");
499			break;
500		}
501	} else if (strcmp(name, "DataDigest") == 0) {
502		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
503			log_debugx("discovery session; digests disabled");
504			keys_add(response_keys, name, "None");
505			return;
506		}
507
508		which = login_list_prefers(value, "CRC32C", "None");
509		switch (which) {
510		case 1:
511			log_debugx("initiator prefers CRC32C "
512			    "for data digest; we'll use it");
513			conn->conn_data_digest = CONN_DIGEST_CRC32C;
514			keys_add(response_keys, name, "CRC32C");
515			break;
516		case 2:
517			log_debugx("initiator prefers not to do "
518			    "data digest; we'll comply");
519			keys_add(response_keys, name, "None");
520			break;
521		default:
522			log_warnx("initiator sent unrecognized "
523			    "DataDigest value \"%s\"; will use None", value);
524			keys_add(response_keys, name, "None");
525			break;
526		}
527	} else if (strcmp(name, "MaxConnections") == 0) {
528		keys_add(response_keys, name, "1");
529	} else if (strcmp(name, "InitialR2T") == 0) {
530		keys_add(response_keys, name, "Yes");
531	} else if (strcmp(name, "ImmediateData") == 0) {
532		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
533			log_debugx("discovery session; ImmediateData irrelevant");
534			keys_add(response_keys, name, "Irrelevant");
535		} else {
536			if (strcmp(value, "Yes") == 0) {
537				conn->conn_immediate_data = true;
538				keys_add(response_keys, name, "Yes");
539			} else {
540				conn->conn_immediate_data = false;
541				keys_add(response_keys, name, "No");
542			}
543		}
544	} else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
545		tmp = strtoul(value, NULL, 10);
546		if (tmp <= 0) {
547			login_send_error(request, 0x02, 0x00);
548			log_errx(1, "received invalid "
549			    "MaxRecvDataSegmentLength");
550		}
551		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
552			log_debugx("capping MaxRecvDataSegmentLength "
553			    "from %d to %d", tmp, MAX_DATA_SEGMENT_LENGTH);
554			tmp = MAX_DATA_SEGMENT_LENGTH;
555		}
556		conn->conn_max_data_segment_length = tmp;
557		keys_add_int(response_keys, name, MAX_DATA_SEGMENT_LENGTH);
558	} else if (strcmp(name, "MaxBurstLength") == 0) {
559		tmp = strtoul(value, NULL, 10);
560		if (tmp <= 0) {
561			login_send_error(request, 0x02, 0x00);
562			log_errx(1, "received invalid MaxBurstLength");
563		}
564		if (tmp > MAX_BURST_LENGTH) {
565			log_debugx("capping MaxBurstLength from %d to %d",
566			    tmp, MAX_BURST_LENGTH);
567			tmp = MAX_BURST_LENGTH;
568		}
569		conn->conn_max_burst_length = tmp;
570		keys_add(response_keys, name, value);
571	} else if (strcmp(name, "FirstBurstLength") == 0) {
572		tmp = strtoul(value, NULL, 10);
573		if (tmp <= 0) {
574			login_send_error(request, 0x02, 0x00);
575			log_errx(1, "received invalid "
576			    "FirstBurstLength");
577		}
578		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
579			log_debugx("capping FirstBurstLength from %d to %d",
580			    tmp, MAX_DATA_SEGMENT_LENGTH);
581			tmp = MAX_DATA_SEGMENT_LENGTH;
582		}
583		/*
584		 * We don't pass the value to the kernel; it only enforces
585		 * hardcoded limit anyway.
586		 */
587		keys_add_int(response_keys, name, tmp);
588	} else if (strcmp(name, "DefaultTime2Wait") == 0) {
589		keys_add(response_keys, name, value);
590	} else if (strcmp(name, "DefaultTime2Retain") == 0) {
591		keys_add(response_keys, name, "0");
592	} else if (strcmp(name, "MaxOutstandingR2T") == 0) {
593		keys_add(response_keys, name, "1");
594	} else if (strcmp(name, "DataPDUInOrder") == 0) {
595		keys_add(response_keys, name, "Yes");
596	} else if (strcmp(name, "DataSequenceInOrder") == 0) {
597		keys_add(response_keys, name, "Yes");
598	} else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
599		keys_add(response_keys, name, "0");
600	} else if (strcmp(name, "OFMarker") == 0) {
601		keys_add(response_keys, name, "No");
602	} else if (strcmp(name, "IFMarker") == 0) {
603		keys_add(response_keys, name, "No");
604	} else if (strcmp(name, "iSCSIProtocolLevel") == 0) {
605		tmp = strtoul(value, NULL, 10);
606		if (tmp > 2)
607			tmp = 2;
608		keys_add_int(response_keys, name, tmp);
609	} else {
610		log_debugx("unknown key \"%s\"; responding "
611		    "with NotUnderstood", name);
612		keys_add(response_keys, name, "NotUnderstood");
613	}
614}
615
616static void
617login_redirect(struct pdu *request, const char *target_address)
618{
619	struct pdu *response;
620	struct iscsi_bhs_login_response *bhslr2;
621	struct keys *response_keys;
622
623	response = login_new_response(request);
624	login_set_csg(response, login_csg(request));
625	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
626	bhslr2->bhslr_status_class = 0x01;
627	bhslr2->bhslr_status_detail = 0x01;
628
629	response_keys = keys_new();
630	keys_add(response_keys, "TargetAddress", target_address);
631
632	keys_save(response_keys, response);
633	pdu_send(response);
634	pdu_delete(response);
635	keys_delete(response_keys);
636}
637
638static bool
639login_portal_redirect(struct connection *conn, struct pdu *request)
640{
641	const struct portal_group *pg;
642
643	pg = conn->conn_portal->p_portal_group;
644	if (pg->pg_redirection == NULL)
645		return (false);
646
647	log_debugx("portal-group \"%s\" configured to redirect to %s",
648	    pg->pg_name, pg->pg_redirection);
649	login_redirect(request, pg->pg_redirection);
650
651	return (true);
652}
653
654static bool
655login_target_redirect(struct connection *conn, struct pdu *request)
656{
657	const char *target_address;
658
659	assert(conn->conn_portal->p_portal_group->pg_redirection == NULL);
660
661	if (conn->conn_target == NULL)
662		return (false);
663
664	target_address = conn->conn_target->t_redirection;
665	if (target_address == NULL)
666		return (false);
667
668	log_debugx("target \"%s\" configured to redirect to %s",
669	  conn->conn_target->t_name, target_address);
670	login_redirect(request, target_address);
671
672	return (true);
673}
674
675static void
676login_negotiate(struct connection *conn, struct pdu *request)
677{
678	struct pdu *response;
679	struct iscsi_bhs_login_response *bhslr2;
680	struct keys *request_keys, *response_keys;
681	int i;
682	bool redirected, skipped_security;
683
684	if (request == NULL) {
685		log_debugx("beginning operational parameter negotiation; "
686		    "waiting for Login PDU");
687		request = login_receive(conn, false);
688		skipped_security = false;
689	} else
690		skipped_security = true;
691
692	/*
693	 * RFC 3720, 10.13.5.  Status-Class and Status-Detail, says
694	 * the redirection SHOULD be accepted by the initiator before
695	 * authentication, but MUST be be accepted afterwards; that's
696	 * why we're doing it here and not earlier.
697	 */
698	redirected = login_target_redirect(conn, request);
699	if (redirected) {
700		log_debugx("initiator redirected; exiting");
701		exit(0);
702	}
703
704	request_keys = keys_new();
705	keys_load(request_keys, request);
706
707	response = login_new_response(request);
708	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
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
743static void
744login_wait_transition(struct connection *conn)
745{
746	struct pdu *request, *response;
747	struct iscsi_bhs_login_request *bhslr;
748
749	log_debugx("waiting for state transition request");
750	request = login_receive(conn, false);
751	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
752	if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0) {
753		login_send_error(request, 0x02, 0x00);
754		log_errx(1, "got no \"T\" flag after answering AuthMethod");
755	}
756	pdu_delete(request);
757
758	log_debugx("got state transition request");
759	response = login_new_response(request);
760	login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
761	pdu_send(response);
762	pdu_delete(response);
763
764	login_negotiate(conn, NULL);
765}
766
767void
768login(struct connection *conn)
769{
770	struct pdu *request, *response;
771	struct iscsi_bhs_login_request *bhslr;
772	struct keys *request_keys, *response_keys;
773	struct auth_group *ag;
774	struct portal_group *pg;
775	const char *initiator_name, *initiator_alias, *session_type,
776	    *target_name, *auth_method;
777	bool redirected, fail, trans;
778
779	/*
780	 * Handle the initial Login Request - figure out required authentication
781	 * method and either transition to the next phase, if no authentication
782	 * is required, or call appropriate authentication code.
783	 */
784	log_debugx("beginning Login Phase; waiting for Login PDU");
785	request = login_receive(conn, true);
786	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
787	if (bhslr->bhslr_tsih != 0) {
788		login_send_error(request, 0x02, 0x0a);
789		log_errx(1, "received Login PDU with non-zero TSIH");
790	}
791
792	pg = conn->conn_portal->p_portal_group;
793
794	memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid,
795	    sizeof(conn->conn_initiator_isid));
796
797	/*
798	 * XXX: Implement the C flag some day.
799	 */
800	request_keys = keys_new();
801	keys_load(request_keys, request);
802
803	assert(conn->conn_initiator_name == NULL);
804	initiator_name = keys_find(request_keys, "InitiatorName");
805	if (initiator_name == NULL) {
806		login_send_error(request, 0x02, 0x07);
807		log_errx(1, "received Login PDU without InitiatorName");
808	}
809	if (valid_iscsi_name(initiator_name) == false) {
810		login_send_error(request, 0x02, 0x00);
811		log_errx(1, "received Login PDU with invalid InitiatorName");
812	}
813	conn->conn_initiator_name = checked_strdup(initiator_name);
814	log_set_peer_name(conn->conn_initiator_name);
815	setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name);
816
817	redirected = login_portal_redirect(conn, request);
818	if (redirected) {
819		log_debugx("initiator redirected; exiting");
820		exit(0);
821	}
822
823	initiator_alias = keys_find(request_keys, "InitiatorAlias");
824	if (initiator_alias != NULL)
825		conn->conn_initiator_alias = checked_strdup(initiator_alias);
826
827	assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE);
828	session_type = keys_find(request_keys, "SessionType");
829	if (session_type != NULL) {
830		if (strcmp(session_type, "Normal") == 0) {
831			conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
832		} else if (strcmp(session_type, "Discovery") == 0) {
833			conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY;
834		} else {
835			login_send_error(request, 0x02, 0x00);
836			log_errx(1, "received Login PDU with invalid "
837			    "SessionType \"%s\"", session_type);
838		}
839	} else
840		conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
841
842	assert(conn->conn_target == NULL);
843	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
844		target_name = keys_find(request_keys, "TargetName");
845		if (target_name == NULL) {
846			login_send_error(request, 0x02, 0x07);
847			log_errx(1, "received Login PDU without TargetName");
848		}
849
850		conn->conn_port = port_find_in_pg(pg, target_name);
851		if (conn->conn_port == NULL) {
852			login_send_error(request, 0x02, 0x03);
853			log_errx(1, "requested target \"%s\" not found",
854			    target_name);
855		}
856		conn->conn_target = conn->conn_port->p_target;
857	}
858
859	/*
860	 * At this point we know what kind of authentication we need.
861	 */
862	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
863		ag = conn->conn_port->p_auth_group;
864		if (ag == NULL)
865			ag = conn->conn_target->t_auth_group;
866		if (ag->ag_name != NULL) {
867			log_debugx("initiator requests to connect "
868			    "to target \"%s\"; auth-group \"%s\"",
869			    conn->conn_target->t_name,
870			    ag->ag_name);
871		} else {
872			log_debugx("initiator requests to connect "
873			    "to target \"%s\"", conn->conn_target->t_name);
874		}
875	} else {
876		assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY);
877		ag = pg->pg_discovery_auth_group;
878		if (ag->ag_name != NULL) {
879			log_debugx("initiator requests "
880			    "discovery session; auth-group \"%s\"", ag->ag_name);
881		} else {
882			log_debugx("initiator requests discovery session");
883		}
884	}
885
886	if (ag->ag_type == AG_TYPE_DENY) {
887		login_send_error(request, 0x02, 0x01);
888		log_errx(1, "auth-type is \"deny\"");
889	}
890
891	if (ag->ag_type == AG_TYPE_UNKNOWN) {
892		/*
893		 * This can happen with empty auth-group.
894		 */
895		login_send_error(request, 0x02, 0x01);
896		log_errx(1, "auth-type not set, denying access");
897	}
898
899	/*
900	 * Enforce initiator-name and initiator-portal.
901	 */
902	if (auth_name_check(ag, initiator_name) != 0) {
903		login_send_error(request, 0x02, 0x02);
904		log_errx(1, "initiator does not match allowed initiator names");
905	}
906
907	if (auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
908		login_send_error(request, 0x02, 0x02);
909		log_errx(1, "initiator does not match allowed "
910		    "initiator portals");
911	}
912
913	/*
914	 * Let's see if the initiator intends to do any kind of authentication
915	 * at all.
916	 */
917	if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
918		if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
919			login_send_error(request, 0x02, 0x01);
920			log_errx(1, "initiator skipped the authentication, "
921			    "but authentication is required");
922		}
923
924		keys_delete(request_keys);
925
926		log_debugx("initiator skipped the authentication, "
927		    "and we don't need it; proceeding with negotiation");
928		login_negotiate(conn, request);
929		return;
930	}
931
932	fail = false;
933	response = login_new_response(request);
934	response_keys = keys_new();
935	trans = (bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) != 0;
936	auth_method = keys_find(request_keys, "AuthMethod");
937	if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) {
938		log_debugx("authentication not required");
939		if (auth_method == NULL ||
940		    login_list_contains(auth_method, "None")) {
941			keys_add(response_keys, "AuthMethod", "None");
942		} else {
943			log_warnx("initiator requests "
944			    "AuthMethod \"%s\" instead of \"None\"",
945			    auth_method);
946			keys_add(response_keys, "AuthMethod", "Reject");
947		}
948		if (trans)
949			login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
950	} else {
951		log_debugx("CHAP authentication required");
952		if (auth_method == NULL ||
953		    login_list_contains(auth_method, "CHAP")) {
954			keys_add(response_keys, "AuthMethod", "CHAP");
955		} else {
956			log_warnx("initiator requests unsupported "
957			    "AuthMethod \"%s\" instead of \"CHAP\"",
958			    auth_method);
959			keys_add(response_keys, "AuthMethod", "Reject");
960			fail = true;
961		}
962	}
963	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
964		if (conn->conn_target->t_alias != NULL)
965			keys_add(response_keys,
966			    "TargetAlias", conn->conn_target->t_alias);
967		keys_add_int(response_keys,
968		    "TargetPortalGroupTag", pg->pg_tag);
969	}
970	keys_save(response_keys, response);
971
972	pdu_send(response);
973	pdu_delete(response);
974	keys_delete(response_keys);
975	pdu_delete(request);
976	keys_delete(request_keys);
977
978	if (fail) {
979		log_debugx("sent reject for AuthMethod; exiting");
980		exit(1);
981	}
982
983	if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
984		login_chap(conn, ag);
985		login_negotiate(conn, NULL);
986	} else if (trans) {
987		login_negotiate(conn, NULL);
988	} else {
989		login_wait_transition(conn);
990	}
991}
992