xref: /illumos-gate/usr/src/cmd/iscsid/iscsid.c (revision 148c5f43199ca0b43fc8e3b643aab11cd66ea327)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/socket.h>
29 #include <signal.h>
30 #include <locale.h>
31 #include <syslog.h>
32 #include <netdb.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <fcntl.h>
36 #include <unistd.h>
37 #include <stdio.h>
38 #include <errno.h>
39 #include <door.h>
40 #include <meta.h>
41 #include <libsysevent.h>
42 #include <wait.h>
43 #include <semaphore.h>
44 #include <libscf.h>
45 
46 #include <sys/scsi/adapters/iscsi_door.h>
47 #include <sys/scsi/adapters/iscsi_if.h>
48 
49 /*
50  * Local Defines
51  * -------------
52  */
53 #define	ISCSI_DOOR_DAEMON_SYSLOG_PP		"iscsid"
54 #define	ISCSI_DISCOVERY_POLL_DELAY1		1	/* Seconds */
55 #define	ISCSI_DISCOVERY_POLL_DELAY2		60	/* Seconds */
56 #define	ISCSI_SMF_OFFLINE_DELAY			10	/* Seconds */
57 #define	ISCSI_SMF_OFFLINE_MAX_RETRY_TIMES	60
58 
59 #if !defined(SMF_EXIT_ERR_OTHER)
60 #define	SMF_EXIT_ERR_OTHER	-1
61 #endif
62 
63 /*
64  * Global Variables related to the synchronization of the child process
65  * --------------------------------------------------------------------
66  */
67 static	pid_t		iscsi_child_pid;
68 static	sem_t		iscsi_child_sem;
69 static	int		iscsi_child_door_handle;
70 static	int		iscsi_child_smf_exit_code;
71 
72 /*
73  * Global Variables related to the door accessed by the kernel
74  * -----------------------------------------------------------
75  */
76 static	int		iscsi_dev_handle;
77 static	int		iscsi_kernel_door_handle;
78 
79 /*
80  * Prototypes of Functions the body of which is defined farther down
81  * in this file.
82  * -----------------------------------------------------------------
83  */
84 static	void		call_child_door(int value);
85 static	void		sigchld_handler(int sig);
86 static	boolean_t	discovery_event_wait(int did);
87 static	void		signone(int, siginfo_t *, void *);
88 
89 static
90 void
91 iscsi_child_door(
92 	void			*cookie,
93 	char			*args,
94 	size_t			alen,
95 	door_desc_t		*ddp,
96 	uint_t			ndid
97 );
98 
99 static
100 void
101 iscsi_kernel_door(
102 	void			*cookie,
103 	char			*args,
104 	size_t			alen,
105 	door_desc_t		*ddp,
106 	uint_t			ndid
107 );
108 
109 static
110 iscsi_door_cnf_t *
111 _getipnodebyname_req(
112 	getipnodebyname_req_t	*req,
113 	int			req_len,
114 	size_t			*pcnf_len
115 );
116 
117 /*
118  * main -- Entry point of the iSCSI door server daemon
119  *
120  * This function forks, waits for the child process feedback and exits.
121  */
122 /* ARGSUSED */
123 int
124 main(
125 	int	argc,
126 	char	*argv[]
127 )
128 {
129 	int			i;
130 	int			sig;
131 	int			ret = -1;
132 	int			retry = 0;
133 	sigset_t		sigs, allsigs;
134 	struct sigaction	act;
135 	uint32_t		rval;
136 
137 	/*
138 	 * Get the locale set up before calling any other routines
139 	 * with messages to ouput.
140 	 */
141 	(void) setlocale(LC_ALL, "");
142 	openlog("ISCSI_DOOR_DAEMON_SYSLOG_PP", LOG_PID, LOG_DAEMON);
143 
144 	/* The child semaphore is created. */
145 	if (sem_init(&iscsi_child_sem, 0, 0) == -1) {
146 		exit(SMF_EXIT_ERR_OTHER);
147 	}
148 
149 	/* The door for the child is created. */
150 	iscsi_child_door_handle = door_create(iscsi_child_door, NULL, 0);
151 	if (iscsi_child_door_handle == -1) {
152 		(void) sem_destroy(&iscsi_child_sem);
153 		exit(SMF_EXIT_ERR_OTHER);
154 	}
155 
156 	/* A signal handler is set for SIGCHLD. */
157 	(void) signal(SIGCHLD, sigchld_handler);
158 
159 	/*
160 	 * Here begins the daemonizing code
161 	 * --------------------------------
162 	 */
163 	iscsi_child_pid = fork();
164 	if (iscsi_child_pid < 0) {
165 		/* The fork failed. */
166 		syslog(LOG_DAEMON | LOG_ERR, gettext("Cannot fork"));
167 		(void) sem_destroy(&iscsi_child_sem);
168 		exit(SMF_EXIT_ERR_OTHER);
169 	}
170 
171 	if (iscsi_child_pid) {
172 		/*
173 		 * The parent exits after the child has provided feedback. This
174 		 * waiting phase is to meet one of greenline's requirements.
175 		 * We shouldn't return till we are sure the service is ready to
176 		 * be provided.
177 		 */
178 		(void) sem_wait(&iscsi_child_sem);
179 		(void) sem_destroy(&iscsi_child_sem);
180 		exit(iscsi_child_smf_exit_code);
181 	}
182 
183 	/*
184 	 * stdout and stderr are redirected to "/dev/null".
185 	 */
186 	i = open("/dev/null", O_RDWR);
187 	(void) dup2(i, 1);
188 	(void) dup2(i, 2);
189 
190 	/*
191 	 * Here ends the daemonizing code
192 	 * ------------------------------
193 	 */
194 
195 	/*
196 	 * Block out all signals
197 	 */
198 	(void) sigfillset(&allsigs);
199 	(void) pthread_sigmask(SIG_BLOCK, &allsigs, NULL);
200 
201 	/* setup the door handle */
202 	iscsi_kernel_door_handle = door_create(iscsi_kernel_door, NULL, 0);
203 	if (iscsi_kernel_door_handle == -1) {
204 		perror(gettext("door_create failed"));
205 		syslog(LOG_DAEMON | LOG_ERR, gettext("door_create failed"));
206 		exit(SMF_EXIT_ERR_OTHER);
207 	}
208 
209 	/*
210 	 * The iSCSI driver is opened.
211 	 */
212 	iscsi_dev_handle = open(ISCSI_DRIVER_DEVCTL, O_RDWR);
213 	if (iscsi_dev_handle == -1) {
214 		/* The driver couldn't be opened. */
215 		perror(gettext("iscsi device open failed"));
216 		exit(SMF_EXIT_ERR_OTHER);
217 	}
218 
219 	if (ioctl(
220 	    iscsi_dev_handle,
221 	    ISCSI_SMF_ONLINE,
222 	    &iscsi_kernel_door_handle) == -1) {
223 		(void) close(iscsi_dev_handle);
224 		perror(gettext("ioctl: enable iscsi initiator"));
225 		exit(SMF_EXIT_ERR_OTHER);
226 	}
227 
228 	/*
229 	 * Keep the dev open, so to keep iscsi module from unloaded.
230 	 * This is crutial to guarantee the consistency of the
231 	 * door_handle and service state in kernel.
232 	 */
233 
234 	/* We have to wait for the discovery process to finish. */
235 	(void) discovery_event_wait(iscsi_dev_handle);
236 
237 	/* We let the parent know that everything is ok. */
238 	call_child_door(SMF_EXIT_OK);
239 
240 	/* now set up signals we care about */
241 
242 	(void) sigemptyset(&sigs);
243 	(void) sigaddset(&sigs, SIGTERM);
244 	(void) sigaddset(&sigs, SIGINT);
245 	(void) sigaddset(&sigs, SIGQUIT);
246 
247 	/* make sure signals to be enqueued */
248 	act.sa_flags = SA_SIGINFO;
249 	act.sa_sigaction = signone;
250 
251 	(void) sigaction(SIGTERM, &act, NULL);
252 	(void) sigaction(SIGINT, &act, NULL);
253 	(void) sigaction(SIGQUIT, &act, NULL);
254 
255 	/* wait and process signals */
256 	for (;;) {
257 		sig = sigwait(&sigs);
258 		if (sig < 0)
259 			continue;
260 		switch (sig) {
261 		case SIGQUIT:
262 		case SIGINT:
263 		case SIGTERM:
264 			do {
265 				ret = ioctl(iscsi_dev_handle,
266 				    ISCSI_SMF_OFFLINE, &rval);
267 				if (ret == -1) {
268 					/*
269 					 * Keep retrying if unable
270 					 * to stop
271 					 */
272 					(void) sleep(ISCSI_SMF_OFFLINE_DELAY);
273 					retry++;
274 				}
275 			} while ((ret == -1) &&
276 			    (retry < ISCSI_SMF_OFFLINE_MAX_RETRY_TIMES));
277 			(void) close(iscsi_dev_handle);
278 			if (rval == B_FALSE) {
279 				syslog(LOG_DAEMON, gettext("iSCSI initiator"
280 				    " service exited with sessions left."));
281 			}
282 			return (0);
283 			break;
284 		default:
285 			break;
286 		}
287 	}
288 }
289 
290 /*
291  * sigchld_handler -- SIGCHLD Handler
292  *
293  */
294 /* ARGSUSED */
295 static
296 void
297 sigchld_handler(
298 	int	sig
299 )
300 {
301 	int	status;
302 	pid_t	ret_pid;
303 
304 	/* This is the default code. */
305 	iscsi_child_smf_exit_code = SMF_EXIT_ERR_OTHER;
306 
307 	ret_pid = waitpid(iscsi_child_pid, &status, WNOHANG);
308 
309 	if (ret_pid == iscsi_child_pid) {
310 		if (WIFEXITED(status)) {
311 			iscsi_child_smf_exit_code = WEXITSTATUS(status);
312 		}
313 	}
314 	(void) sem_post(&iscsi_child_sem);
315 }
316 
317 /*
318  * iscsi_child_door -- Child process door entry point
319  *
320  * This function is executed when a driver calls door_ki_upcall().
321  */
322 /* ARGSUSED */
323 static
324 void
325 iscsi_child_door(
326 	void		*cookie,
327 	char		*args,
328 	size_t		alen,
329 	door_desc_t	*ddp,
330 	uint_t		ndid
331 )
332 {
333 	int		*ptr = (int *)args;
334 
335 	iscsi_child_smf_exit_code = SMF_EXIT_ERR_OTHER;
336 
337 	if (alen >= sizeof (iscsi_child_smf_exit_code)) {
338 		iscsi_child_smf_exit_code = *ptr;
339 	}
340 	(void) sem_post(&iscsi_child_sem);
341 	(void) door_return(NULL, 0, NULL, 0);
342 }
343 
344 /*
345  * iscsi_kernel_door -- Kernel door entry point
346  *
347  * This function is executed when a driver calls door_ki_upcall().
348  */
349 /* ARGSUSED */
350 static
351 void
352 iscsi_kernel_door(
353 	void		*cookie,
354 	char		*args,
355 	size_t		alen,
356 	door_desc_t	*ddp,
357 	uint_t		ndid
358 )
359 {
360 	iscsi_door_msg_hdr_t	err_ind;
361 	iscsi_door_req_t	*req;
362 	iscsi_door_cnf_t	*cnf;
363 	size_t			cnf_len;
364 	char			*err_txt;
365 	int			err_code;
366 
367 	/* Local variables pre-initialization */
368 	err_ind.signature = ISCSI_DOOR_REQ_SIGNATURE;
369 	err_ind.version	  = ISCSI_DOOR_REQ_VERSION_1;
370 	err_ind.opcode	  = ISCSI_DOOR_ERROR_IND;
371 
372 	req = (iscsi_door_req_t *)args;
373 	cnf = (iscsi_door_cnf_t *)&err_ind;
374 	cnf_len = sizeof (err_ind);
375 
376 	/*
377 	 * The validity of the request is checked before going any farther.
378 	 */
379 	if (req == NULL) {
380 		/*
381 		 * A request has to be passed.
382 		 */
383 		err_ind.status = ISCSI_DOOR_STATUS_REQ_INVALID;
384 	} else if (alen < sizeof (iscsi_door_msg_hdr_t)) {
385 		/*
386 		 * The buffer containing the request must be at least as big
387 		 * as message header.
388 		 */
389 		err_ind.status = ISCSI_DOOR_STATUS_REQ_LENGTH;
390 	} else if (req->hdr.signature != ISCSI_DOOR_REQ_SIGNATURE) {
391 		/*
392 		 * The request must be correctly signed.
393 		 */
394 		err_ind.status = ISCSI_DOOR_STATUS_REQ_INVALID;
395 	} else if (req->hdr.version != ISCSI_DOOR_REQ_VERSION_1) {
396 		/*
397 		 * The version of the request must be supported by the server.
398 		 */
399 		err_ind.status = ISCSI_DOOR_STATUS_REQ_VERSION;
400 	} else {
401 		/*
402 		 * The request is treated according to the opcode.
403 		 */
404 		switch (req->hdr.opcode) {
405 
406 		case ISCSI_DOOR_GETIPNODEBYNAME_REQ:
407 			cnf = _getipnodebyname_req(
408 			    &req->ginbn_req,
409 			    alen,
410 			    &cnf_len);
411 			break;
412 		default:
413 			err_ind.status = ISCSI_DOOR_STATUS_REQ_INVALID;
414 			break;
415 		}
416 	}
417 	err_code = door_return((char *)cnf, cnf_len, NULL, 0);
418 
419 	switch (err_code) {
420 	case E2BIG:
421 		err_txt = "E2BIG";
422 		break;
423 	case EFAULT:
424 		err_txt = "EFAULT";
425 		break;
426 	case EINVAL:
427 		err_txt = "EINVAL";
428 		break;
429 	case EMFILE:
430 		err_txt = "EMFILE";
431 		break;
432 	default:
433 		err_txt = "?";
434 		break;
435 	}
436 	(void) fprintf(stderr, "door_return error(%s,%d)", err_txt, err_code);
437 	syslog(
438 	    LOG_DAEMON | LOG_ERR,
439 	    gettext("!door_return error(%s,%d)"),
440 	    err_txt,
441 	    err_code);
442 }
443 
444 /*
445  * _getipnodebyname_req
446  *
447  * This function executes the request ISCSI_DOOR_GETIPNODEBYNAME_REQ.  It
448  * calls getipnodebyname() but doesn't return all the information.  The
449  * confirmation structure only contains one IP address of the list returned
450  * by getipnodebyname().
451  */
452 static
453 iscsi_door_cnf_t *
454 _getipnodebyname_req(
455 	getipnodebyname_req_t	*req,
456 	int			req_len,
457 	size_t			*pcnf_len
458 ) {
459 	getipnodebyname_cnf_t	*cnf = (getipnodebyname_cnf_t *)req;
460 	size_t			cnf_len;
461 	struct hostent		*hptr;
462 	char			*name;
463 
464 	/* The opcode is changed immediately. */
465 	cnf->hdr.opcode = ISCSI_DOOR_GETIPNODEBYNAME_CNF;
466 
467 	/* The size of the request is checked against the minimum required. */
468 	if (req_len < sizeof (getipnodebyname_cnf_t)) {
469 		cnf->hdr.status = ISCSI_DOOR_STATUS_REQ_FORMAT;
470 		*pcnf_len = req_len;
471 		return ((iscsi_door_cnf_t *)cnf);
472 	}
473 
474 	name = (char *)req + req->name_offset;
475 
476 	/*
477 	 * The pointer to the name has to stay inside the request but
478 	 * after the header.
479 	 */
480 	if ((name < ((char *)req + sizeof (getipnodebyname_req_t))) ||
481 	    ((name + req->name_length) > ((char *)req + req_len))) {
482 		cnf->hdr.status = ISCSI_DOOR_STATUS_REQ_FORMAT;
483 		*pcnf_len = req_len;
484 		return ((iscsi_door_cnf_t *)cnf);
485 	}
486 
487 	/* The library function is called. */
488 	hptr = getipnodebyname(
489 			name,
490 			(int)req->af,
491 			(int)req->flags,
492 			(int *)&cnf->error_num);
493 
494 	if (hptr) {
495 		/*
496 		 * The call was successful. Now starts the painful work of
497 		 * parsing the data.  However, for version 1 we will only
498 		 * return the first address.
499 		 */
500 		cnf_len = sizeof (getipnodebyname_cnf_t);
501 		cnf->h_size_needed = sizeof (getipnodebyname_cnf_t);
502 		cnf->h_alias_list_length = 0;
503 		cnf->h_alias_list_offset = 0;
504 		cnf->h_name_len = 0;
505 		cnf->h_name_offset = 0;
506 
507 		cnf->h_addrlen = (uint32_t)hptr->h_length;
508 		cnf->h_addrtype = (uint32_t)hptr->h_addrtype;
509 		cnf->h_addr_list_offset = sizeof (getipnodebyname_cnf_t);
510 
511 		if (*hptr->h_addr_list != NULL) {
512 			(void) memcpy(
513 				((char *)cnf + sizeof (getipnodebyname_cnf_t)),
514 				*hptr->h_addr_list,
515 				hptr->h_length);
516 			cnf->h_addr_list_length = 1;
517 			cnf->h_size_needed += cnf->h_addrlen;
518 			cnf_len += hptr->h_length;
519 		} else {
520 			cnf->h_addr_list_length = 0;
521 			cnf->h_size_needed += hptr->h_length;
522 		}
523 		*pcnf_len = cnf_len;
524 		cnf->hdr.status = ISCSI_DOOR_STATUS_SUCCESS;
525 		freehostent(hptr);
526 	} else {
527 		cnf->hdr.status = ISCSI_DOOR_STATUS_SUCCESS;
528 		cnf->h_addrlen = 0;
529 		cnf->h_addrtype = 0;
530 		cnf->h_addr_list_offset = sizeof (getipnodebyname_cnf_t);
531 		cnf->h_addr_list_length = 0;
532 		cnf->h_name_offset = sizeof (getipnodebyname_cnf_t);
533 		cnf->h_name_len = 0;
534 		cnf->h_alias_list_offset = sizeof (getipnodebyname_cnf_t);
535 		cnf->h_alias_list_length = 0;
536 		cnf->h_size_needed = sizeof (getipnodebyname_cnf_t);
537 		*pcnf_len = sizeof (getipnodebyname_cnf_t);
538 	}
539 	return ((iscsi_door_cnf_t *)cnf);
540 }
541 
542 /*
543  * call_child_door -- This function calls the child door with the value
544  *		      provided by the caller.
545  *
546  */
547 static
548 void
549 call_child_door(
550 	int		value
551 )
552 {
553 	door_arg_t	door_arg;
554 
555 	(void) memset(&door_arg, 0, sizeof (door_arg));
556 	door_arg.data_ptr = (char *)&value;
557 	door_arg.data_size = sizeof (value);
558 	(void) door_call(iscsi_child_door_handle, &door_arg);
559 }
560 
561 /*
562  * get_luns_count --
563  */
564 static
565 uint32_t
566 get_luns_count(
567 	int		did
568 )
569 {
570 	iscsi_lun_list_t	*lun_list;
571 	iscsi_lun_list_t	*tmp;
572 	size_t			len;
573 	uint32_t		lun_count;
574 
575 	lun_list = (iscsi_lun_list_t *)malloc(sizeof (*lun_list));
576 
577 	(void) memset(lun_list, 0, sizeof (*lun_list));
578 	lun_list->ll_vers = ISCSI_INTERFACE_VERSION;
579 	lun_list->ll_in_cnt = 1;
580 	lun_list->ll_all_tgts = B_TRUE;
581 
582 	for (;;) {
583 
584 		if (ioctl(
585 		    did,
586 		    ISCSI_LUN_OID_LIST_GET,
587 		    lun_list) == -1) {
588 			free(lun_list);
589 			/* The Ioctl didn't go well. */
590 			return (0);
591 		}
592 		if (lun_list->ll_in_cnt >= lun_list->ll_out_cnt) {
593 			/* We got it all. */
594 			break;
595 		}
596 		/*
597 		 * We didn't get all the targets. Let's build a new Ioctl with
598 		 * a new size.
599 		 */
600 		tmp  = lun_list;
601 		len  = tmp->ll_out_cnt * sizeof (tmp->ll_luns);
602 		len += sizeof (*tmp) - sizeof (tmp->ll_luns);
603 		lun_list = (iscsi_lun_list_t *)malloc(len);
604 		if (lun_list == NULL) {
605 			/* No resources. */
606 			free(tmp);
607 			return (0);
608 		}
609 		(void) memset(lun_list, 0, len);
610 		lun_list->ll_vers = ISCSI_INTERFACE_VERSION;
611 		lun_list->ll_in_cnt = tmp->ll_out_cnt;
612 		lun_list->ll_all_tgts = B_TRUE;
613 		free(tmp);
614 	}
615 	lun_count = lun_list->ll_out_cnt;
616 	free(lun_list);
617 	return (lun_count);
618 }
619 
620 /*
621  * discovery_event_wait -- Waits for the discovery process to finish.
622  *
623  */
624 static
625 boolean_t
626 discovery_event_wait(
627 	int		did
628 )
629 {
630 	boolean_t		rc;
631 	uint32_t		lun_count;
632 	uint32_t		lun_timer;
633 	uint32_t		tmp;
634 	iSCSIDiscoveryMethod_t  discovery_flags;
635 	iSCSIDiscoveryMethod_t  discovery_all;
636 
637 	rc = B_FALSE;
638 	lun_count = 0;
639 	lun_timer = 0;
640 	discovery_flags = 0;
641 	discovery_all = iSCSIDiscoveryMethodStatic |
642 	    iSCSIDiscoveryMethodSLP |
643 	    iSCSIDiscoveryMethodISNS |
644 	    iSCSIDiscoveryMethodSendTargets;
645 
646 	for (;;) {
647 
648 		/* The status discovery flags are read. */
649 		if (ioctl(
650 		    did,
651 		    ISCSI_DISCOVERY_EVENTS,
652 		    &discovery_flags) == -1) {
653 			/* IO problem */
654 			break;
655 		}
656 
657 		if (discovery_flags == discovery_all) {
658 			/* Discovery over */
659 			rc = B_TRUE;
660 			break;
661 		}
662 
663 		if (lun_timer >= ISCSI_DISCOVERY_POLL_DELAY2) {
664 			/* Let's check if the driver is making progress. */
665 			tmp = get_luns_count(did);
666 			if (tmp <= lun_count) {
667 				/* No progress */
668 				break;
669 			}
670 			lun_count = tmp;
671 			lun_timer = 0;
672 		}
673 		(void) sleep(ISCSI_DISCOVERY_POLL_DELAY1);
674 		lun_timer += ISCSI_DISCOVERY_POLL_DELAY1;
675 	}
676 	return (rc);
677 }
678 
679 /*ARGSUSED*/
680 static void
681 signone(int sig, siginfo_t *sip, void *utp)
682 {
683 }
684