login.c revision 286801
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 286801 2015-08-15 11:08:30Z mav $");
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	bhslr->bhslr_flags |= BHSLR_FLAGS_TRANSIT;
63}
64
65static int
66login_csg(const struct pdu *request)
67{
68	struct iscsi_bhs_login_request *bhslr;
69
70	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
71
72	return ((bhslr->bhslr_flags & 0x0C) >> 2);
73}
74
75static void
76login_set_csg(struct pdu *response, int csg)
77{
78	struct iscsi_bhs_login_response *bhslr;
79
80	assert(csg == BHSLR_STAGE_SECURITY_NEGOTIATION ||
81	    csg == BHSLR_STAGE_OPERATIONAL_NEGOTIATION ||
82	    csg == BHSLR_STAGE_FULL_FEATURE_PHASE);
83
84	bhslr = (struct iscsi_bhs_login_response *)response->pdu_bhs;
85
86	bhslr->bhslr_flags &= 0xF3;
87	bhslr->bhslr_flags |= csg << 2;
88}
89
90static struct pdu *
91login_receive(struct connection *conn, bool initial)
92{
93	struct pdu *request;
94	struct iscsi_bhs_login_request *bhslr;
95
96	request = pdu_new(conn);
97	pdu_receive(request);
98	if ((request->pdu_bhs->bhs_opcode & ~ISCSI_BHS_OPCODE_IMMEDIATE) !=
99	    ISCSI_BHS_OPCODE_LOGIN_REQUEST) {
100		/*
101		 * The first PDU in session is special - if we receive any PDU
102		 * different than login request, we have to drop the connection
103		 * without sending response ("A target receiving any PDU
104		 * except a Login request before the Login Phase is started MUST
105		 * immediately terminate the connection on which the PDU
106		 * was received.")
107		 */
108		if (initial == false)
109			login_send_error(request, 0x02, 0x0b);
110		log_errx(1, "protocol error: received invalid opcode 0x%x",
111		    request->pdu_bhs->bhs_opcode);
112	}
113	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
114	/*
115	 * XXX: Implement the C flag some day.
116	 */
117	if ((bhslr->bhslr_flags & BHSLR_FLAGS_CONTINUE) != 0) {
118		login_send_error(request, 0x03, 0x00);
119		log_errx(1, "received Login PDU with unsupported \"C\" flag");
120	}
121	if (bhslr->bhslr_version_max != 0x00) {
122		login_send_error(request, 0x02, 0x05);
123		log_errx(1, "received Login PDU with unsupported "
124		    "Version-max 0x%x", bhslr->bhslr_version_max);
125	}
126	if (bhslr->bhslr_version_min != 0x00) {
127		login_send_error(request, 0x02, 0x05);
128		log_errx(1, "received Login PDU with unsupported "
129		    "Version-min 0x%x", bhslr->bhslr_version_min);
130	}
131	if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
132		login_send_error(request, 0x02, 0x05);
133		log_errx(1, "received Login PDU with decreasing CmdSN: "
134		    "was %u, is %u", conn->conn_cmdsn,
135		    ntohl(bhslr->bhslr_cmdsn));
136	}
137	if (initial == false &&
138	    ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
139		login_send_error(request, 0x02, 0x05);
140		log_errx(1, "received Login PDU with wrong ExpStatSN: "
141		    "is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
142		    conn->conn_statsn);
143	}
144	conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);
145
146	return (request);
147}
148
149static struct pdu *
150login_new_response(struct pdu *request)
151{
152	struct pdu *response;
153	struct connection *conn;
154	struct iscsi_bhs_login_request *bhslr;
155	struct iscsi_bhs_login_response *bhslr2;
156
157	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
158	conn = request->pdu_connection;
159
160	response = pdu_new_response(request);
161	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
162	bhslr2->bhslr_opcode = ISCSI_BHS_OPCODE_LOGIN_RESPONSE;
163	login_set_csg(response, BHSLR_STAGE_SECURITY_NEGOTIATION);
164	memcpy(bhslr2->bhslr_isid,
165	    bhslr->bhslr_isid, sizeof(bhslr2->bhslr_isid));
166	bhslr2->bhslr_initiator_task_tag = bhslr->bhslr_initiator_task_tag;
167	bhslr2->bhslr_statsn = htonl(conn->conn_statsn++);
168	bhslr2->bhslr_expcmdsn = htonl(conn->conn_cmdsn);
169	bhslr2->bhslr_maxcmdsn = htonl(conn->conn_cmdsn);
170
171	return (response);
172}
173
174static void
175login_send_error(struct pdu *request, char class, char detail)
176{
177	struct pdu *response;
178	struct iscsi_bhs_login_response *bhslr2;
179
180	log_debugx("sending Login Response PDU with failure class 0x%x/0x%x; "
181	    "see next line for reason", class, detail);
182	response = login_new_response(request);
183	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
184	bhslr2->bhslr_status_class = class;
185	bhslr2->bhslr_status_detail = detail;
186
187	pdu_send(response);
188	pdu_delete(response);
189}
190
191static int
192login_list_contains(const char *list, const char *what)
193{
194	char *tofree, *str, *token;
195
196	tofree = str = checked_strdup(list);
197
198	while ((token = strsep(&str, ",")) != NULL) {
199		if (strcmp(token, what) == 0) {
200			free(tofree);
201			return (1);
202		}
203	}
204	free(tofree);
205	return (0);
206}
207
208static int
209login_list_prefers(const char *list,
210    const char *choice1, const char *choice2)
211{
212	char *tofree, *str, *token;
213
214	tofree = str = checked_strdup(list);
215
216	while ((token = strsep(&str, ",")) != NULL) {
217		if (strcmp(token, choice1) == 0) {
218			free(tofree);
219			return (1);
220		}
221		if (strcmp(token, choice2) == 0) {
222			free(tofree);
223			return (2);
224		}
225	}
226	free(tofree);
227	return (-1);
228}
229
230static struct pdu *
231login_receive_chap_a(struct connection *conn)
232{
233	struct pdu *request;
234	struct keys *request_keys;
235	const char *chap_a;
236
237	request = login_receive(conn, false);
238	request_keys = keys_new();
239	keys_load(request_keys, request);
240
241	chap_a = keys_find(request_keys, "CHAP_A");
242	if (chap_a == NULL) {
243		login_send_error(request, 0x02, 0x07);
244		log_errx(1, "received CHAP Login PDU without CHAP_A");
245	}
246	if (login_list_contains(chap_a, "5") == 0) {
247		login_send_error(request, 0x02, 0x01);
248		log_errx(1, "received CHAP Login PDU with unsupported CHAP_A "
249		    "\"%s\"", chap_a);
250	}
251	keys_delete(request_keys);
252
253	return (request);
254}
255
256static void
257login_send_chap_c(struct pdu *request, struct chap *chap)
258{
259	struct pdu *response;
260	struct keys *response_keys;
261	char *chap_c, *chap_i;
262
263	chap_c = chap_get_challenge(chap);
264	chap_i = chap_get_id(chap);
265
266	response = login_new_response(request);
267	response_keys = keys_new();
268	keys_add(response_keys, "CHAP_A", "5");
269	keys_add(response_keys, "CHAP_I", chap_i);
270	keys_add(response_keys, "CHAP_C", chap_c);
271	free(chap_i);
272	free(chap_c);
273	keys_save(response_keys, response);
274	pdu_send(response);
275	pdu_delete(response);
276	keys_delete(response_keys);
277}
278
279static struct pdu *
280login_receive_chap_r(struct connection *conn, struct auth_group *ag,
281    struct chap *chap, const struct auth **authp)
282{
283	struct pdu *request;
284	struct keys *request_keys;
285	const char *chap_n, *chap_r;
286	const struct auth *auth;
287	int error;
288
289	request = login_receive(conn, false);
290	request_keys = keys_new();
291	keys_load(request_keys, request);
292
293	chap_n = keys_find(request_keys, "CHAP_N");
294	if (chap_n == NULL) {
295		login_send_error(request, 0x02, 0x07);
296		log_errx(1, "received CHAP Login PDU without CHAP_N");
297	}
298	chap_r = keys_find(request_keys, "CHAP_R");
299	if (chap_r == NULL) {
300		login_send_error(request, 0x02, 0x07);
301		log_errx(1, "received CHAP Login PDU without CHAP_R");
302	}
303	error = chap_receive(chap, chap_r);
304	if (error != 0) {
305		login_send_error(request, 0x02, 0x07);
306		log_errx(1, "received CHAP Login PDU with malformed CHAP_R");
307	}
308
309	/*
310	 * Verify the response.
311	 */
312	assert(ag->ag_type == AG_TYPE_CHAP ||
313	    ag->ag_type == AG_TYPE_CHAP_MUTUAL);
314	auth = auth_find(ag, chap_n);
315	if (auth == NULL) {
316		login_send_error(request, 0x02, 0x01);
317		log_errx(1, "received CHAP Login with invalid user \"%s\"",
318		    chap_n);
319	}
320
321	assert(auth->a_secret != NULL);
322	assert(strlen(auth->a_secret) > 0);
323
324	error = chap_authenticate(chap, auth->a_secret);
325	if (error != 0) {
326		login_send_error(request, 0x02, 0x01);
327		log_errx(1, "CHAP authentication failed for user \"%s\"",
328		    auth->a_user);
329	}
330
331	keys_delete(request_keys);
332
333	*authp = auth;
334	return (request);
335}
336
337static void
338login_send_chap_success(struct pdu *request,
339    const struct auth *auth)
340{
341	struct pdu *response;
342	struct keys *request_keys, *response_keys;
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	login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
350
351	/*
352	 * Actually, one more thing: mutual authentication.
353	 */
354	request_keys = keys_new();
355	keys_load(request_keys, request);
356	chap_i = keys_find(request_keys, "CHAP_I");
357	chap_c = keys_find(request_keys, "CHAP_C");
358	if (chap_i != NULL || chap_c != NULL) {
359		if (chap_i == NULL) {
360			login_send_error(request, 0x02, 0x07);
361			log_errx(1, "initiator requested target "
362			    "authentication, but didn't send CHAP_I");
363		}
364		if (chap_c == NULL) {
365			login_send_error(request, 0x02, 0x07);
366			log_errx(1, "initiator requested target "
367			    "authentication, but didn't send CHAP_C");
368		}
369		if (auth->a_auth_group->ag_type != AG_TYPE_CHAP_MUTUAL) {
370			login_send_error(request, 0x02, 0x01);
371			log_errx(1, "initiator requests target authentication "
372			    "for user \"%s\", but mutual user/secret "
373			    "is not set", auth->a_user);
374		}
375
376		log_debugx("performing mutual authentication as user \"%s\"",
377		    auth->a_mutual_user);
378
379		rchap = rchap_new(auth->a_mutual_secret);
380		error = rchap_receive(rchap, chap_i, chap_c);
381		if (error != 0) {
382			login_send_error(request, 0x02, 0x07);
383			log_errx(1, "received CHAP Login PDU with malformed "
384			    "CHAP_I or CHAP_C");
385		}
386		chap_r = rchap_get_response(rchap);
387		rchap_delete(rchap);
388		response_keys = keys_new();
389		keys_add(response_keys, "CHAP_N", auth->a_mutual_user);
390		keys_add(response_keys, "CHAP_R", chap_r);
391		free(chap_r);
392		keys_save(response_keys, response);
393		keys_delete(response_keys);
394	} else {
395		log_debugx("initiator did not request target authentication");
396	}
397
398	keys_delete(request_keys);
399	pdu_send(response);
400	pdu_delete(response);
401}
402
403static void
404login_chap(struct connection *conn, struct auth_group *ag)
405{
406	const struct auth *auth;
407	struct chap *chap;
408	struct pdu *request;
409
410	/*
411	 * Receive CHAP_A PDU.
412	 */
413	log_debugx("beginning CHAP authentication; waiting for CHAP_A");
414	request = login_receive_chap_a(conn);
415
416	/*
417	 * Generate the challenge.
418	 */
419	chap = chap_new();
420
421	/*
422	 * Send the challenge.
423	 */
424	log_debugx("sending CHAP_C, binary challenge size is %zd bytes",
425	    sizeof(chap->chap_challenge));
426	login_send_chap_c(request, chap);
427	pdu_delete(request);
428
429	/*
430	 * Receive CHAP_N/CHAP_R PDU and authenticate.
431	 */
432	log_debugx("waiting for CHAP_N/CHAP_R");
433	request = login_receive_chap_r(conn, ag, chap, &auth);
434
435	/*
436	 * Yay, authentication succeeded!
437	 */
438	log_debugx("authentication succeeded for user \"%s\"; "
439	    "transitioning to Negotiation Phase", auth->a_user);
440	login_send_chap_success(request, auth);
441	pdu_delete(request);
442
443	/*
444	 * Leave username and CHAP information for discovery().
445	 */
446	conn->conn_user = auth->a_user;
447	conn->conn_chap = chap;
448}
449
450static void
451login_negotiate_key(struct pdu *request, const char *name,
452    const char *value, bool skipped_security, struct keys *response_keys)
453{
454	int which, tmp;
455	struct connection *conn;
456
457	conn = request->pdu_connection;
458
459	if (strcmp(name, "InitiatorName") == 0) {
460		if (!skipped_security)
461			log_errx(1, "initiator resent InitiatorName");
462	} else if (strcmp(name, "SessionType") == 0) {
463		if (!skipped_security)
464			log_errx(1, "initiator resent SessionType");
465	} else if (strcmp(name, "TargetName") == 0) {
466		if (!skipped_security)
467			log_errx(1, "initiator resent TargetName");
468	} else if (strcmp(name, "InitiatorAlias") == 0) {
469		if (conn->conn_initiator_alias != NULL)
470			free(conn->conn_initiator_alias);
471		conn->conn_initiator_alias = checked_strdup(value);
472	} else if (strcmp(value, "Irrelevant") == 0) {
473		/* Ignore. */
474	} else if (strcmp(name, "HeaderDigest") == 0) {
475		/*
476		 * We don't handle digests for discovery sessions.
477		 */
478		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
479			log_debugx("discovery session; digests disabled");
480			keys_add(response_keys, name, "None");
481			return;
482		}
483
484		which = login_list_prefers(value, "CRC32C", "None");
485		switch (which) {
486		case 1:
487			log_debugx("initiator prefers CRC32C "
488			    "for header digest; we'll use it");
489			conn->conn_header_digest = CONN_DIGEST_CRC32C;
490			keys_add(response_keys, name, "CRC32C");
491			break;
492		case 2:
493			log_debugx("initiator prefers not to do "
494			    "header digest; we'll comply");
495			keys_add(response_keys, name, "None");
496			break;
497		default:
498			log_warnx("initiator sent unrecognized "
499			    "HeaderDigest value \"%s\"; will use None", value);
500			keys_add(response_keys, name, "None");
501			break;
502		}
503	} else if (strcmp(name, "DataDigest") == 0) {
504		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
505			log_debugx("discovery session; digests disabled");
506			keys_add(response_keys, name, "None");
507			return;
508		}
509
510		which = login_list_prefers(value, "CRC32C", "None");
511		switch (which) {
512		case 1:
513			log_debugx("initiator prefers CRC32C "
514			    "for data digest; we'll use it");
515			conn->conn_data_digest = CONN_DIGEST_CRC32C;
516			keys_add(response_keys, name, "CRC32C");
517			break;
518		case 2:
519			log_debugx("initiator prefers not to do "
520			    "data digest; we'll comply");
521			keys_add(response_keys, name, "None");
522			break;
523		default:
524			log_warnx("initiator sent unrecognized "
525			    "DataDigest value \"%s\"; will use None", value);
526			keys_add(response_keys, name, "None");
527			break;
528		}
529	} else if (strcmp(name, "MaxConnections") == 0) {
530		keys_add(response_keys, name, "1");
531	} else if (strcmp(name, "InitialR2T") == 0) {
532		keys_add(response_keys, name, "Yes");
533	} else if (strcmp(name, "ImmediateData") == 0) {
534		if (conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY) {
535			log_debugx("discovery session; ImmediateData irrelevant");
536			keys_add(response_keys, name, "Irrelevant");
537		} else {
538			if (strcmp(value, "Yes") == 0) {
539				conn->conn_immediate_data = true;
540				keys_add(response_keys, name, "Yes");
541			} else {
542				conn->conn_immediate_data = false;
543				keys_add(response_keys, name, "No");
544			}
545		}
546	} else if (strcmp(name, "MaxRecvDataSegmentLength") == 0) {
547		tmp = strtoul(value, NULL, 10);
548		if (tmp <= 0) {
549			login_send_error(request, 0x02, 0x00);
550			log_errx(1, "received invalid "
551			    "MaxRecvDataSegmentLength");
552		}
553		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
554			log_debugx("capping MaxRecvDataSegmentLength "
555			    "from %d to %d", tmp, MAX_DATA_SEGMENT_LENGTH);
556			tmp = MAX_DATA_SEGMENT_LENGTH;
557		}
558		conn->conn_max_data_segment_length = tmp;
559		keys_add_int(response_keys, name, MAX_DATA_SEGMENT_LENGTH);
560	} else if (strcmp(name, "MaxBurstLength") == 0) {
561		tmp = strtoul(value, NULL, 10);
562		if (tmp <= 0) {
563			login_send_error(request, 0x02, 0x00);
564			log_errx(1, "received invalid MaxBurstLength");
565		}
566		if (tmp > MAX_BURST_LENGTH) {
567			log_debugx("capping MaxBurstLength from %d to %d",
568			    tmp, MAX_BURST_LENGTH);
569			tmp = MAX_BURST_LENGTH;
570		}
571		conn->conn_max_burst_length = tmp;
572		keys_add(response_keys, name, value);
573	} else if (strcmp(name, "FirstBurstLength") == 0) {
574		tmp = strtoul(value, NULL, 10);
575		if (tmp <= 0) {
576			login_send_error(request, 0x02, 0x00);
577			log_errx(1, "received invalid "
578			    "FirstBurstLength");
579		}
580		if (tmp > MAX_DATA_SEGMENT_LENGTH) {
581			log_debugx("capping FirstBurstLength from %d to %d",
582			    tmp, MAX_DATA_SEGMENT_LENGTH);
583			tmp = MAX_DATA_SEGMENT_LENGTH;
584		}
585		/*
586		 * We don't pass the value to the kernel; it only enforces
587		 * hardcoded limit anyway.
588		 */
589		keys_add_int(response_keys, name, tmp);
590	} else if (strcmp(name, "DefaultTime2Wait") == 0) {
591		keys_add(response_keys, name, value);
592	} else if (strcmp(name, "DefaultTime2Retain") == 0) {
593		keys_add(response_keys, name, "0");
594	} else if (strcmp(name, "MaxOutstandingR2T") == 0) {
595		keys_add(response_keys, name, "1");
596	} else if (strcmp(name, "DataPDUInOrder") == 0) {
597		keys_add(response_keys, name, "Yes");
598	} else if (strcmp(name, "DataSequenceInOrder") == 0) {
599		keys_add(response_keys, name, "Yes");
600	} else if (strcmp(name, "ErrorRecoveryLevel") == 0) {
601		keys_add(response_keys, name, "0");
602	} else if (strcmp(name, "OFMarker") == 0) {
603		keys_add(response_keys, name, "No");
604	} else if (strcmp(name, "IFMarker") == 0) {
605		keys_add(response_keys, name, "No");
606	} else {
607		log_debugx("unknown key \"%s\"; responding "
608		    "with NotUnderstood", name);
609		keys_add(response_keys, name, "NotUnderstood");
610	}
611}
612
613static void
614login_redirect(struct pdu *request, const char *target_address)
615{
616	struct pdu *response;
617	struct iscsi_bhs_login_response *bhslr2;
618	struct keys *response_keys;
619
620	response = login_new_response(request);
621	login_set_csg(response, login_csg(request));
622	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
623	bhslr2->bhslr_status_class = 0x01;
624	bhslr2->bhslr_status_detail = 0x01;
625
626	response_keys = keys_new();
627	keys_add(response_keys, "TargetAddress", target_address);
628
629	keys_save(response_keys, response);
630	pdu_send(response);
631	pdu_delete(response);
632	keys_delete(response_keys);
633}
634
635static bool
636login_portal_redirect(struct connection *conn, struct pdu *request)
637{
638	const struct portal_group *pg;
639
640	pg = conn->conn_portal->p_portal_group;
641	if (pg->pg_redirection == NULL)
642		return (false);
643
644	log_debugx("portal-group \"%s\" configured to redirect to %s",
645	    pg->pg_name, pg->pg_redirection);
646	login_redirect(request, pg->pg_redirection);
647
648	return (true);
649}
650
651static bool
652login_target_redirect(struct connection *conn, struct pdu *request)
653{
654	const char *target_address;
655
656	assert(conn->conn_portal->p_portal_group->pg_redirection == NULL);
657
658	if (conn->conn_target == NULL)
659		return (false);
660
661	target_address = conn->conn_target->t_redirection;
662	if (target_address == NULL)
663		return (false);
664
665	log_debugx("target \"%s\" configured to redirect to %s",
666	  conn->conn_target->t_name, target_address);
667	login_redirect(request, target_address);
668
669	return (true);
670}
671
672static void
673login_negotiate(struct connection *conn, struct pdu *request)
674{
675	struct pdu *response;
676	struct iscsi_bhs_login_response *bhslr2;
677	struct keys *request_keys, *response_keys;
678	int i;
679	bool redirected, skipped_security;
680
681	if (request == NULL) {
682		log_debugx("beginning operational parameter negotiation; "
683		    "waiting for Login PDU");
684		request = login_receive(conn, false);
685		skipped_security = false;
686	} else
687		skipped_security = true;
688
689	/*
690	 * RFC 3720, 10.13.5.  Status-Class and Status-Detail, says
691	 * the redirection SHOULD be accepted by the initiator before
692	 * authentication, but MUST be be accepted afterwards; that's
693	 * why we're doing it here and not earlier.
694	 */
695	redirected = login_target_redirect(conn, request);
696	if (redirected) {
697		log_debugx("initiator redirected; exiting");
698		exit(0);
699	}
700
701	request_keys = keys_new();
702	keys_load(request_keys, request);
703
704	response = login_new_response(request);
705	bhslr2 = (struct iscsi_bhs_login_response *)response->pdu_bhs;
706	bhslr2->bhslr_tsih = htons(0xbadd);
707	login_set_csg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
708	login_set_nsg(response, BHSLR_STAGE_FULL_FEATURE_PHASE);
709	response_keys = keys_new();
710
711	if (skipped_security &&
712	    conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
713		if (conn->conn_target->t_alias != NULL)
714			keys_add(response_keys,
715			    "TargetAlias", conn->conn_target->t_alias);
716		keys_add_int(response_keys, "TargetPortalGroupTag",
717		    conn->conn_portal->p_portal_group->pg_tag);
718	}
719
720	for (i = 0; i < KEYS_MAX; i++) {
721		if (request_keys->keys_names[i] == NULL)
722			break;
723
724		login_negotiate_key(request, request_keys->keys_names[i],
725		    request_keys->keys_values[i], skipped_security,
726		    response_keys);
727	}
728
729	log_debugx("operational parameter negotiation done; "
730	    "transitioning to Full Feature Phase");
731
732	keys_save(response_keys, response);
733	pdu_send(response);
734	pdu_delete(response);
735	keys_delete(response_keys);
736	pdu_delete(request);
737	keys_delete(request_keys);
738}
739
740void
741login(struct connection *conn)
742{
743	struct pdu *request, *response;
744	struct iscsi_bhs_login_request *bhslr;
745	struct keys *request_keys, *response_keys;
746	struct auth_group *ag;
747	struct portal_group *pg;
748	const char *initiator_name, *initiator_alias, *session_type,
749	    *target_name, *auth_method;
750	bool redirected;
751
752	/*
753	 * Handle the initial Login Request - figure out required authentication
754	 * method and either transition to the next phase, if no authentication
755	 * is required, or call appropriate authentication code.
756	 */
757	log_debugx("beginning Login Phase; waiting for Login PDU");
758	request = login_receive(conn, true);
759	bhslr = (struct iscsi_bhs_login_request *)request->pdu_bhs;
760	if (bhslr->bhslr_tsih != 0) {
761		login_send_error(request, 0x02, 0x0a);
762		log_errx(1, "received Login PDU with non-zero TSIH");
763	}
764
765	pg = conn->conn_portal->p_portal_group;
766
767	memcpy(conn->conn_initiator_isid, bhslr->bhslr_isid,
768	    sizeof(conn->conn_initiator_isid));
769
770	/*
771	 * XXX: Implement the C flag some day.
772	 */
773	request_keys = keys_new();
774	keys_load(request_keys, request);
775
776	assert(conn->conn_initiator_name == NULL);
777	initiator_name = keys_find(request_keys, "InitiatorName");
778	if (initiator_name == NULL) {
779		login_send_error(request, 0x02, 0x07);
780		log_errx(1, "received Login PDU without InitiatorName");
781	}
782	if (valid_iscsi_name(initiator_name) == false) {
783		login_send_error(request, 0x02, 0x00);
784		log_errx(1, "received Login PDU with invalid InitiatorName");
785	}
786	conn->conn_initiator_name = checked_strdup(initiator_name);
787	log_set_peer_name(conn->conn_initiator_name);
788	setproctitle("%s (%s)", conn->conn_initiator_addr, conn->conn_initiator_name);
789
790	redirected = login_portal_redirect(conn, request);
791	if (redirected) {
792		log_debugx("initiator redirected; exiting");
793		exit(0);
794	}
795
796	initiator_alias = keys_find(request_keys, "InitiatorAlias");
797	if (initiator_alias != NULL)
798		conn->conn_initiator_alias = checked_strdup(initiator_alias);
799
800	assert(conn->conn_session_type == CONN_SESSION_TYPE_NONE);
801	session_type = keys_find(request_keys, "SessionType");
802	if (session_type != NULL) {
803		if (strcmp(session_type, "Normal") == 0) {
804			conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
805		} else if (strcmp(session_type, "Discovery") == 0) {
806			conn->conn_session_type = CONN_SESSION_TYPE_DISCOVERY;
807		} else {
808			login_send_error(request, 0x02, 0x00);
809			log_errx(1, "received Login PDU with invalid "
810			    "SessionType \"%s\"", session_type);
811		}
812	} else
813		conn->conn_session_type = CONN_SESSION_TYPE_NORMAL;
814
815	assert(conn->conn_target == NULL);
816	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
817		target_name = keys_find(request_keys, "TargetName");
818		if (target_name == NULL) {
819			login_send_error(request, 0x02, 0x07);
820			log_errx(1, "received Login PDU without TargetName");
821		}
822
823		conn->conn_port = port_find_in_pg(pg, target_name);
824		if (conn->conn_port == NULL) {
825			login_send_error(request, 0x02, 0x03);
826			log_errx(1, "requested target \"%s\" not found",
827			    target_name);
828		}
829		conn->conn_target = conn->conn_port->p_target;
830	}
831
832	/*
833	 * At this point we know what kind of authentication we need.
834	 */
835	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
836		ag = conn->conn_port->p_auth_group;
837		if (ag == NULL)
838			ag = conn->conn_target->t_auth_group;
839		if (ag->ag_name != NULL) {
840			log_debugx("initiator requests to connect "
841			    "to target \"%s\"; auth-group \"%s\"",
842			    conn->conn_target->t_name,
843			    ag->ag_name);
844		} else {
845			log_debugx("initiator requests to connect "
846			    "to target \"%s\"", conn->conn_target->t_name);
847		}
848	} else {
849		assert(conn->conn_session_type == CONN_SESSION_TYPE_DISCOVERY);
850		ag = pg->pg_discovery_auth_group;
851		if (ag->ag_name != NULL) {
852			log_debugx("initiator requests "
853			    "discovery session; auth-group \"%s\"", ag->ag_name);
854		} else {
855			log_debugx("initiator requests discovery session");
856		}
857	}
858
859	/*
860	 * Enforce initiator-name and initiator-portal.
861	 */
862	if (auth_name_check(ag, initiator_name) != 0) {
863		login_send_error(request, 0x02, 0x02);
864		log_errx(1, "initiator does not match allowed initiator names");
865	}
866
867	if (auth_portal_check(ag, &conn->conn_initiator_sa) != 0) {
868		login_send_error(request, 0x02, 0x02);
869		log_errx(1, "initiator does not match allowed "
870		    "initiator portals");
871	}
872
873	/*
874	 * Let's see if the initiator intends to do any kind of authentication
875	 * at all.
876	 */
877	if (login_csg(request) == BHSLR_STAGE_OPERATIONAL_NEGOTIATION) {
878		if (ag->ag_type != AG_TYPE_NO_AUTHENTICATION) {
879			login_send_error(request, 0x02, 0x01);
880			log_errx(1, "initiator skipped the authentication, "
881			    "but authentication is required");
882		}
883
884		keys_delete(request_keys);
885
886		log_debugx("initiator skipped the authentication, "
887		    "and we don't need it; proceeding with negotiation");
888		login_negotiate(conn, request);
889		return;
890	}
891
892	if (ag->ag_type == AG_TYPE_NO_AUTHENTICATION) {
893		/*
894		 * Initiator might want to to authenticate,
895		 * but we don't need it.
896		 */
897		log_debugx("authentication not required; "
898		    "transitioning to operational parameter negotiation");
899
900		if ((bhslr->bhslr_flags & BHSLR_FLAGS_TRANSIT) == 0)
901			log_warnx("initiator did not set the \"T\" flag; "
902			    "transitioning anyway");
903
904		response = login_new_response(request);
905		login_set_nsg(response, BHSLR_STAGE_OPERATIONAL_NEGOTIATION);
906		response_keys = keys_new();
907		/*
908		 * Required by Linux initiator.
909		 */
910		auth_method = keys_find(request_keys, "AuthMethod");
911		if (auth_method != NULL &&
912		    login_list_contains(auth_method, "None"))
913			keys_add(response_keys, "AuthMethod", "None");
914
915		if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
916			if (conn->conn_target->t_alias != NULL)
917				keys_add(response_keys,
918				    "TargetAlias", conn->conn_target->t_alias);
919			keys_add_int(response_keys,
920			    "TargetPortalGroupTag", pg->pg_tag);
921		}
922		keys_save(response_keys, response);
923		pdu_send(response);
924		pdu_delete(response);
925		keys_delete(response_keys);
926		pdu_delete(request);
927		keys_delete(request_keys);
928
929		login_negotiate(conn, NULL);
930		return;
931	}
932
933	if (ag->ag_type == AG_TYPE_DENY) {
934		login_send_error(request, 0x02, 0x01);
935		log_errx(1, "auth-type is \"deny\"");
936	}
937
938	if (ag->ag_type == AG_TYPE_UNKNOWN) {
939		/*
940		 * This can happen with empty auth-group.
941		 */
942		login_send_error(request, 0x02, 0x01);
943		log_errx(1, "auth-type not set, denying access");
944	}
945
946	log_debugx("CHAP authentication required");
947
948	auth_method = keys_find(request_keys, "AuthMethod");
949	if (auth_method == NULL) {
950		login_send_error(request, 0x02, 0x07);
951		log_errx(1, "received Login PDU without AuthMethod");
952	}
953	/*
954	 * XXX: This should be Reject, not just a login failure (5.3.2).
955	 */
956	if (login_list_contains(auth_method, "CHAP") == 0) {
957		login_send_error(request, 0x02, 0x01);
958		log_errx(1, "initiator requests unsupported AuthMethod \"%s\" "
959		    "instead of \"CHAP\"", auth_method);
960	}
961
962	response = login_new_response(request);
963
964	response_keys = keys_new();
965	keys_add(response_keys, "AuthMethod", "CHAP");
966	if (conn->conn_session_type == CONN_SESSION_TYPE_NORMAL) {
967		if (conn->conn_target->t_alias != NULL)
968			keys_add(response_keys,
969			    "TargetAlias", conn->conn_target->t_alias);
970		keys_add_int(response_keys,
971		    "TargetPortalGroupTag", pg->pg_tag);
972	}
973	keys_save(response_keys, response);
974
975	pdu_send(response);
976	pdu_delete(response);
977	keys_delete(response_keys);
978	pdu_delete(request);
979	keys_delete(request_keys);
980
981	login_chap(conn, ag);
982
983	login_negotiate(conn, NULL);
984}
985