xref: /illumos-gate/usr/src/lib/libdladm/common/libdladm.c (revision 1f6352c601b7f3c744b4684ff673c813927da24c)
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 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <unistd.h>
27 #include <errno.h>
28 #include <ctype.h>
29 #include <fcntl.h>
30 #include <strings.h>
31 #include <dirent.h>
32 #include <stdlib.h>
33 #include <sys/param.h>
34 #include <sys/stat.h>
35 #include <sys/dld.h>
36 #include <libdladm_impl.h>
37 #include <libintl.h>
38 #include <libdlpi.h>
39 
40 static char	dladm_rootdir[MAXPATHLEN] = "/";
41 
42 dladm_status_t
43 dladm_open(dladm_handle_t *handle)
44 {
45 	int dld_fd;
46 
47 	if (handle == NULL)
48 		return (DLADM_STATUS_BADARG);
49 
50 	if ((dld_fd = open(DLD_CONTROL_DEV, O_RDWR)) < 0)
51 		return (dladm_errno2status(errno));
52 
53 	/*
54 	 * Don't open DLMGMT_DOOR now.  dlmgmtd(1M) is not able to
55 	 * open the door when the dladm handle is opened because the
56 	 * door hasn't been created yet at that time.  Thus, we must
57 	 * open it on-demand in dladm_door_fd().  Move the open()
58 	 * to dladm_door_fd() for all cases.
59 	 */
60 
61 	if ((*handle = malloc(sizeof (struct dladm_handle))) == NULL) {
62 		(void) close(dld_fd);
63 		return (DLADM_STATUS_NOMEM);
64 	}
65 
66 	(*handle)->dld_fd = dld_fd;
67 	(*handle)->door_fd = -1;
68 
69 	return (DLADM_STATUS_OK);
70 }
71 
72 void
73 dladm_close(dladm_handle_t handle)
74 {
75 	if (handle != NULL) {
76 		(void) close(handle->dld_fd);
77 		if (handle->door_fd != -1)
78 			(void) close(handle->door_fd);
79 		free(handle);
80 	}
81 }
82 
83 int
84 dladm_dld_fd(dladm_handle_t handle)
85 {
86 	return (handle->dld_fd);
87 }
88 
89 /*
90  * If DLMGMT_DOOR hasn't been opened in the handle yet, open it.
91  */
92 dladm_status_t
93 dladm_door_fd(dladm_handle_t handle, int *door_fd)
94 {
95 	int fd;
96 
97 	if (handle->door_fd == -1) {
98 		if ((fd = open(DLMGMT_DOOR, O_RDONLY)) < 0)
99 			return (dladm_errno2status(errno));
100 		handle->door_fd = fd;
101 	}
102 	*door_fd = handle->door_fd;
103 
104 	return (DLADM_STATUS_OK);
105 }
106 
107 const char *
108 dladm_status2str(dladm_status_t status, char *buf)
109 {
110 	const char	*s;
111 
112 	switch (status) {
113 	case DLADM_STATUS_OK:
114 		s = "ok";
115 		break;
116 	case DLADM_STATUS_BADARG:
117 		s = "invalid argument";
118 		break;
119 	case DLADM_STATUS_FAILED:
120 		s = "operation failed";
121 		break;
122 	case DLADM_STATUS_TOOSMALL:
123 		s = "buffer size too small";
124 		break;
125 	case DLADM_STATUS_NOTSUP:
126 		s = "operation not supported";
127 		break;
128 	case DLADM_STATUS_NOTFOUND:
129 		s = "object not found";
130 		break;
131 	case DLADM_STATUS_BADVAL:
132 		s = "invalid value";
133 		break;
134 	case DLADM_STATUS_NOMEM:
135 		s = "insufficient memory";
136 		break;
137 	case DLADM_STATUS_EXIST:
138 		s = "object already exists";
139 		break;
140 	case DLADM_STATUS_LINKINVAL:
141 		s = "invalid link";
142 		break;
143 	case DLADM_STATUS_PROPRDONLY:
144 		s = "read-only property";
145 		break;
146 	case DLADM_STATUS_BADVALCNT:
147 		s = "invalid number of values";
148 		break;
149 	case DLADM_STATUS_DBNOTFOUND:
150 		s = "database not found";
151 		break;
152 	case DLADM_STATUS_DENIED:
153 		s = "permission denied";
154 		break;
155 	case DLADM_STATUS_IOERR:
156 		s = "I/O error";
157 		break;
158 	case DLADM_STATUS_TEMPONLY:
159 		s = "change cannot be persistent";
160 		break;
161 	case DLADM_STATUS_TIMEDOUT:
162 		s = "operation timed out";
163 		break;
164 	case DLADM_STATUS_ISCONN:
165 		s = "already connected";
166 		break;
167 	case DLADM_STATUS_NOTCONN:
168 		s = "not connected";
169 		break;
170 	case DLADM_STATUS_REPOSITORYINVAL:
171 		s = "invalid configuration repository";
172 		break;
173 	case DLADM_STATUS_MACADDRINVAL:
174 		s = "invalid MAC address";
175 		break;
176 	case DLADM_STATUS_KEYINVAL:
177 		s = "invalid key";
178 		break;
179 	case DLADM_STATUS_INVALIDMACADDRLEN:
180 		s = "invalid MAC address length";
181 		break;
182 	case DLADM_STATUS_INVALIDMACADDRTYPE:
183 		s = "invalid MAC address type";
184 		break;
185 	case DLADM_STATUS_LINKBUSY:
186 		s = "link busy";
187 		break;
188 	case DLADM_STATUS_VIDINVAL:
189 		s = "invalid VLAN identifier";
190 		break;
191 	case DLADM_STATUS_TRYAGAIN:
192 		s = "try again later";
193 		break;
194 	case DLADM_STATUS_NONOTIF:
195 		s = "link notification is not supported";
196 		break;
197 	case DLADM_STATUS_BADTIMEVAL:
198 		s = "invalid time range";
199 		break;
200 	case DLADM_STATUS_INVALIDMACADDR:
201 		s = "invalid MAC address value";
202 		break;
203 	case DLADM_STATUS_INVALIDMACADDRNIC:
204 		s = "MAC address reserved for use by underlying data-link";
205 		break;
206 	case DLADM_STATUS_INVALIDMACADDRINUSE:
207 		s = "MAC address is already in use";
208 		break;
209 	case DLADM_STATUS_MACFACTORYSLOTINVALID:
210 		s = "invalid factory MAC address slot";
211 		break;
212 	case DLADM_STATUS_MACFACTORYSLOTUSED:
213 		s = "factory MAC address slot already used";
214 		break;
215 	case DLADM_STATUS_MACFACTORYSLOTALLUSED:
216 		s = "all factory MAC address slots are in use";
217 		break;
218 	case DLADM_STATUS_MACFACTORYNOTSUP:
219 		s = "factory MAC address slots not supported";
220 		break;
221 	case DLADM_STATUS_INVALIDMACPREFIX:
222 		s = "Invalid MAC address prefix value";
223 		break;
224 	case DLADM_STATUS_INVALIDMACPREFIXLEN:
225 		s = "Invalid MAC address prefix length";
226 		break;
227 	case DLADM_STATUS_CPUMAX:
228 		s = "non-existent processor ID";
229 		break;
230 	case DLADM_STATUS_CPUERR:
231 		s = "could not determine processor status";
232 		break;
233 	case DLADM_STATUS_CPUNOTONLINE:
234 		s = "processor not online";
235 		break;
236 	case DLADM_STATUS_DB_NOTFOUND:
237 		s = "database not found";
238 		break;
239 	case DLADM_STATUS_DB_PARSE_ERR:
240 		s = "database parse error";
241 		break;
242 	case DLADM_STATUS_PROP_PARSE_ERR:
243 		s = "property parse error";
244 		break;
245 	case DLADM_STATUS_ATTR_PARSE_ERR:
246 		s = "attribute parse error";
247 		break;
248 	case DLADM_STATUS_FLOW_DB_ERR:
249 		s = "flow database error";
250 		break;
251 	case DLADM_STATUS_FLOW_DB_OPEN_ERR:
252 		s = "flow database open error";
253 		break;
254 	case DLADM_STATUS_FLOW_DB_PARSE_ERR:
255 		s = "flow database parse error";
256 		break;
257 	case DLADM_STATUS_FLOWPROP_DB_PARSE_ERR:
258 		s = "flow property database parse error";
259 		break;
260 	case DLADM_STATUS_FLOW_ADD_ERR:
261 		s = "flow add error";
262 		break;
263 	case DLADM_STATUS_FLOW_WALK_ERR:
264 		s = "flow walk error";
265 		break;
266 	case DLADM_STATUS_FLOW_IDENTICAL:
267 		s = "a flow with identical attributes exists";
268 		break;
269 	case DLADM_STATUS_FLOW_INCOMPATIBLE:
270 		s = "flow(s) with incompatible attributes exists";
271 		break;
272 	case DLADM_STATUS_FLOW_EXISTS:
273 		s = "link still has flows";
274 		break;
275 	case DLADM_STATUS_PERSIST_FLOW_EXISTS:
276 		s = "persistent flow with the same name exists";
277 		break;
278 	case DLADM_STATUS_INVALID_IP:
279 		s = "invalid IP address";
280 		break;
281 	case DLADM_STATUS_INVALID_PREFIXLEN:
282 		s = "invalid IP prefix length";
283 		break;
284 	case DLADM_STATUS_INVALID_PROTOCOL:
285 		s = "invalid IP protocol";
286 		break;
287 	case DLADM_STATUS_INVALID_PORT:
288 		s = "invalid port number";
289 		break;
290 	case DLADM_STATUS_INVALID_DSF:
291 		s = "invalid dsfield";
292 		break;
293 	case DLADM_STATUS_INVALID_DSFMASK:
294 		s = "invalid dsfield mask";
295 		break;
296 	case DLADM_STATUS_INVALID_MACMARGIN:
297 		s = "MTU check failed, use lower MTU or -f option";
298 		break;
299 	case DLADM_STATUS_BADPROP:
300 		s = "invalid property";
301 		break;
302 	case DLADM_STATUS_MINMAXBW:
303 		s = "minimum value for maxbw is 1.2M";
304 		break;
305 	case DLADM_STATUS_NO_HWRINGS:
306 		s = "request hw rings failed";
307 		break;
308 	default:
309 		s = "<unknown error>";
310 		break;
311 	}
312 	(void) snprintf(buf, DLADM_STRSIZE, "%s", dgettext(TEXT_DOMAIN, s));
313 	return (buf);
314 }
315 
316 /*
317  * Convert a unix errno to a dladm_status_t.
318  * We only convert errnos that are likely to be encountered. All others
319  * are mapped to DLADM_STATUS_FAILED.
320  */
321 dladm_status_t
322 dladm_errno2status(int err)
323 {
324 	switch (err) {
325 	case 0:
326 		return (DLADM_STATUS_OK);
327 	case EINVAL:
328 		return (DLADM_STATUS_BADARG);
329 	case EEXIST:
330 		return (DLADM_STATUS_EXIST);
331 	case ENOENT:
332 		return (DLADM_STATUS_NOTFOUND);
333 	case ENOSPC:
334 		return (DLADM_STATUS_TOOSMALL);
335 	case ENOMEM:
336 		return (DLADM_STATUS_NOMEM);
337 	case ENOTSUP:
338 		return (DLADM_STATUS_NOTSUP);
339 	case ENETDOWN:
340 		return (DLADM_STATUS_NONOTIF);
341 	case EACCES:
342 	case EPERM:
343 		return (DLADM_STATUS_DENIED);
344 	case EIO:
345 		return (DLADM_STATUS_IOERR);
346 	case EBUSY:
347 		return (DLADM_STATUS_LINKBUSY);
348 	case EAGAIN:
349 		return (DLADM_STATUS_TRYAGAIN);
350 	case ENOTEMPTY:
351 		return (DLADM_STATUS_FLOW_EXISTS);
352 	case EOPNOTSUPP:
353 		return (DLADM_STATUS_FLOW_INCOMPATIBLE);
354 	case EALREADY:
355 		return (DLADM_STATUS_FLOW_IDENTICAL);
356 	default:
357 		return (DLADM_STATUS_FAILED);
358 	}
359 }
360 
361 dladm_status_t
362 dladm_str2bw(char *oarg, uint64_t *bw)
363 {
364 	char		*endp = NULL;
365 	int64_t		n;
366 	int		mult = 1;
367 
368 	n = strtoull(oarg, &endp, 10);
369 
370 	if ((errno != 0) || (strlen(endp) > 1))
371 		return (DLADM_STATUS_BADARG);
372 
373 	if (n < 0)
374 		return (DLADM_STATUS_BADVAL);
375 
376 	switch (*endp) {
377 	case 'k':
378 	case 'K':
379 		mult = 1000;
380 		break;
381 	case 'm':
382 	case 'M':
383 	case '\0':
384 		mult = 1000000;
385 		break;
386 	case 'g':
387 	case 'G':
388 		mult = 1000000000;
389 		break;
390 	case '%':
391 		/*
392 		 * percentages not supported for now,
393 		 * see RFE 6540675
394 		 */
395 		return (DLADM_STATUS_NOTSUP);
396 	default:
397 		return (DLADM_STATUS_BADVAL);
398 	}
399 
400 	*bw = n * mult;
401 
402 	/* check for overflow */
403 	if (*bw / mult != n)
404 		return (DLADM_STATUS_BADARG);
405 
406 	return (DLADM_STATUS_OK);
407 }
408 
409 /*
410  * Convert bandwidth in bps to a string in mpbs.  For values greater
411  * than 1mbps or 1000000, print a whole mbps value.  For values that
412  * have fractional Mbps in whole Kbps , print the bandwidth in a manner
413  * simlilar to a floating point format.
414  *
415  *        bps       string
416  *          0            0
417  *        100            0
418  *       2000        0.002
419  *     431000        0.431
420  *    1000000            1
421  *    1030000        1.030
422  *  100000000          100
423  */
424 const char *
425 dladm_bw2str(int64_t bw, char *buf)
426 {
427 	int kbps, mbps;
428 
429 	kbps = (bw%1000000)/1000;
430 	mbps = bw/1000000;
431 	if (kbps != 0) {
432 		if (mbps == 0)
433 			(void) snprintf(buf, DLADM_STRSIZE, "0.%03u", kbps);
434 		else
435 			(void) snprintf(buf, DLADM_STRSIZE, "%5u.%03u", mbps,
436 			    kbps);
437 	} else {
438 		(void) snprintf(buf, DLADM_STRSIZE, "%5u", mbps);
439 	}
440 
441 	return (buf);
442 }
443 
444 #define	LOCK_DB_PERMS	S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH
445 
446 static int
447 i_dladm_lock_db(const char *lock_file, short type)
448 {
449 	int	lock_fd;
450 	struct	flock lock;
451 
452 	if ((lock_fd = open(lock_file, O_RDWR | O_CREAT | O_TRUNC,
453 	    LOCK_DB_PERMS)) < 0)
454 		return (-1);
455 
456 	lock.l_type = type;
457 	lock.l_whence = SEEK_SET;
458 	lock.l_start = 0;
459 	lock.l_len = 0;
460 
461 	if (fcntl(lock_fd, F_SETLKW, &lock) < 0) {
462 		int err = errno;
463 
464 		(void) close(lock_fd);
465 		(void) unlink(lock_file);
466 		errno = err;
467 		return (-1);
468 	}
469 	return (lock_fd);
470 }
471 
472 static void
473 i_dladm_unlock_db(const char *lock_file, int fd)
474 {
475 	struct flock lock;
476 
477 	if (fd < 0)
478 		return;
479 
480 	lock.l_type = F_UNLCK;
481 	lock.l_whence = SEEK_SET;
482 	lock.l_start = 0;
483 	lock.l_len = 0;
484 
485 	(void) fcntl(fd, F_SETLKW, &lock);
486 	(void) close(fd);
487 	(void) unlink(lock_file);
488 }
489 
490 /*
491  * Given a link class, returns its class string.
492  */
493 const char *
494 dladm_class2str(datalink_class_t class, char *buf)
495 {
496 	const char *s;
497 
498 	switch (class) {
499 	case DATALINK_CLASS_PHYS:
500 		s = "phys";
501 		break;
502 	case DATALINK_CLASS_VLAN:
503 		s = "vlan";
504 		break;
505 	case DATALINK_CLASS_AGGR:
506 		s = "aggr";
507 		break;
508 	case DATALINK_CLASS_VNIC:
509 		s = "vnic";
510 		break;
511 	case DATALINK_CLASS_ETHERSTUB:
512 		s = "etherstub";
513 		break;
514 	default:
515 		s = "unknown";
516 		break;
517 	}
518 
519 	(void) snprintf(buf, DLADM_STRSIZE, "%s", s);
520 	return (buf);
521 }
522 
523 /*
524  * Given a physical link media type, returns its media type string.
525  */
526 const char *
527 dladm_media2str(uint32_t media, char *buf)
528 {
529 	const char *s;
530 
531 	switch (media) {
532 	case DL_ETHER:
533 		s = "Ethernet";
534 		break;
535 	case DL_WIFI:
536 		s = "WiFi";
537 		break;
538 	case DL_IB:
539 		s = "Infiniband";
540 		break;
541 	case DL_IPV4:
542 		s = "IPv4Tunnel";
543 		break;
544 	case DL_IPV6:
545 		s = "IPv6Tunnel";
546 		break;
547 	case DL_CSMACD:
548 		s = "CSMA/CD";
549 		break;
550 	case DL_TPB:
551 		s = "TokenBus";
552 		break;
553 	case DL_TPR:
554 		s = "TokenRing";
555 		break;
556 	case DL_METRO:
557 		s = "MetroNet";
558 		break;
559 	case DL_HDLC:
560 		s = "HDLC";
561 		break;
562 	case DL_CHAR:
563 		s = "SyncCharacter";
564 		break;
565 	case DL_CTCA:
566 		s = "CTCA";
567 		break;
568 	case DL_FDDI:
569 		s = "FDDI";
570 		break;
571 	case DL_FC:
572 		s = "FiberChannel";
573 		break;
574 	case DL_ATM:
575 		s = "ATM";
576 		break;
577 	case DL_IPATM:
578 		s = "ATM(ClassicIP)";
579 		break;
580 	case DL_X25:
581 		s = "X.25";
582 		break;
583 	case DL_IPX25:
584 		s = "X.25(ClassicIP)";
585 		break;
586 	case DL_ISDN:
587 		s = "ISDN";
588 		break;
589 	case DL_HIPPI:
590 		s = "HIPPI";
591 		break;
592 	case DL_100VG:
593 		s = "100BaseVGEthernet";
594 		break;
595 	case DL_100VGTPR:
596 		s = "100BaseVGTokenRing";
597 		break;
598 	case DL_ETH_CSMA:
599 		s = "IEEE802.3";
600 		break;
601 	case DL_100BT:
602 		s = "100BaseT";
603 		break;
604 	case DL_FRAME:
605 		s = "FrameRelay";
606 		break;
607 	case DL_MPFRAME:
608 		s = "MPFrameRelay";
609 		break;
610 	case DL_ASYNC:
611 		s = "AsyncCharacter";
612 		break;
613 	case DL_IPNET:
614 		s = "IPNET";
615 		break;
616 	default:
617 		s = "--";
618 		break;
619 	}
620 
621 	(void) snprintf(buf, DLADM_STRSIZE, "%s", s);
622 	return (buf);
623 }
624 
625 dladm_status_t
626 i_dladm_rw_db(dladm_handle_t handle, const char *db_file, mode_t db_perms,
627     dladm_status_t (*process_db)(dladm_handle_t, void *, FILE *, FILE *),
628     void *arg, boolean_t writeop)
629 {
630 	dladm_status_t	status = DLADM_STATUS_OK;
631 	FILE		*fp, *nfp = NULL;
632 	char		lock[MAXPATHLEN];
633 	char		file[MAXPATHLEN];
634 	char		newfile[MAXPATHLEN];
635 	char		*db_basename;
636 	int		nfd, lock_fd;
637 
638 	/*
639 	 * If we are called from a boot script such as net-physical,
640 	 * it's quite likely that the root fs is still not writable.
641 	 * For this case, it's ok for the lock creation to fail since
642 	 * no one else could be accessing our configuration file.
643 	 */
644 	db_basename = strrchr(db_file, '/');
645 	if (db_basename == NULL || db_basename[1] == '\0')
646 		return (dladm_errno2status(EINVAL));
647 	db_basename++;
648 	(void) snprintf(lock, MAXPATHLEN, "/tmp/%s.lock", db_basename);
649 	if ((lock_fd = i_dladm_lock_db
650 	    (lock, (writeop ? F_WRLCK : F_RDLCK))) < 0 && errno != EROFS)
651 		return (dladm_errno2status(errno));
652 
653 	(void) snprintf(file, MAXPATHLEN, "%s/%s", dladm_rootdir, db_file);
654 	if ((fp = fopen(file, (writeop ? "r+" : "r"))) == NULL) {
655 		int	err = errno;
656 
657 		i_dladm_unlock_db(lock, lock_fd);
658 		if (err == ENOENT)
659 			return (DLADM_STATUS_DBNOTFOUND);
660 
661 		return (dladm_errno2status(err));
662 	}
663 
664 	if (writeop) {
665 		(void) snprintf(newfile, MAXPATHLEN, "%s/%s.new",
666 		    dladm_rootdir, db_file);
667 		if ((nfd = open(newfile, O_WRONLY | O_CREAT | O_TRUNC,
668 		    db_perms)) < 0) {
669 			(void) fclose(fp);
670 			i_dladm_unlock_db(lock, lock_fd);
671 			return (dladm_errno2status(errno));
672 		}
673 
674 		if ((nfp = fdopen(nfd, "w")) == NULL) {
675 			(void) close(nfd);
676 			(void) fclose(fp);
677 			(void) unlink(newfile);
678 			i_dladm_unlock_db(lock, lock_fd);
679 			return (dladm_errno2status(errno));
680 		}
681 	}
682 	status = (*process_db)(handle, arg, fp, nfp);
683 	if (!writeop || status != DLADM_STATUS_OK)
684 		goto done;
685 
686 	/*
687 	 * Configuration files need to be owned by the 'dladm' user.
688 	 * If we are invoked by root, the file ownership needs to be fixed.
689 	 */
690 	if (getuid() == 0 || geteuid() == 0) {
691 		if (fchown(nfd, UID_DLADM, GID_SYS) < 0) {
692 			status = dladm_errno2status(errno);
693 			goto done;
694 		}
695 	}
696 
697 	if (fflush(nfp) == EOF) {
698 		status = dladm_errno2status(errno);
699 		goto done;
700 	}
701 	(void) fclose(fp);
702 	(void) fclose(nfp);
703 
704 	if (rename(newfile, file) < 0) {
705 		(void) unlink(newfile);
706 		i_dladm_unlock_db(lock, lock_fd);
707 		return (dladm_errno2status(errno));
708 	}
709 
710 	i_dladm_unlock_db(lock, lock_fd);
711 	return (DLADM_STATUS_OK);
712 
713 done:
714 	if (nfp != NULL) {
715 		(void) fclose(nfp);
716 		if (status != DLADM_STATUS_OK)
717 			(void) unlink(newfile);
718 	}
719 	(void) fclose(fp);
720 	i_dladm_unlock_db(lock, lock_fd);
721 	return (status);
722 }
723 
724 dladm_status_t
725 dladm_set_rootdir(const char *rootdir)
726 {
727 	DIR	*dp;
728 
729 	if (rootdir == NULL || *rootdir != '/' ||
730 	    (dp = opendir(rootdir)) == NULL)
731 		return (DLADM_STATUS_BADARG);
732 
733 	(void) strncpy(dladm_rootdir, rootdir, MAXPATHLEN);
734 	(void) closedir(dp);
735 	return (DLADM_STATUS_OK);
736 }
737 
738 boolean_t
739 dladm_valid_linkname(const char *link)
740 {
741 	size_t		len = strlen(link);
742 	const char	*cp;
743 
744 	if (len + 1 >= MAXLINKNAMELEN)
745 		return (B_FALSE);
746 
747 	/*
748 	 * The link name cannot start with a digit and must end with a digit.
749 	 */
750 	if ((isdigit(link[0]) != 0) || (isdigit(link[len - 1]) == 0))
751 		return (B_FALSE);
752 
753 	/*
754 	 * The legal characters in a link name are:
755 	 * alphanumeric (a-z,  A-Z,  0-9), and the underscore ('_').
756 	 */
757 	for (cp = link; *cp != '\0'; cp++) {
758 		if ((isalnum(*cp) == 0) && (*cp != '_'))
759 			return (B_FALSE);
760 	}
761 
762 	return (B_TRUE);
763 }
764 
765 /*
766  * Convert priority string to a value.
767  */
768 dladm_status_t
769 dladm_str2pri(char *token, mac_priority_level_t *pri)
770 {
771 	if (strlen(token) == strlen("low") &&
772 	    strncasecmp(token, "low", strlen("low")) == 0) {
773 		*pri = MPL_LOW;
774 	} else if (strlen(token) == strlen("medium") &&
775 	    strncasecmp(token, "medium", strlen("medium")) == 0) {
776 		*pri = MPL_MEDIUM;
777 	} else if (strlen(token) == strlen("high") &&
778 	    strncasecmp(token, "high", strlen("high")) == 0) {
779 		*pri = MPL_HIGH;
780 	} else {
781 		return (DLADM_STATUS_BADVAL);
782 	}
783 	return (DLADM_STATUS_OK);
784 }
785 
786 /*
787  * Convert priority value to a string.
788  */
789 const char *
790 dladm_pri2str(mac_priority_level_t pri, char *buf)
791 {
792 	const char	*s;
793 
794 	switch (pri) {
795 	case MPL_LOW:
796 		s = "low";
797 		break;
798 	case MPL_MEDIUM:
799 		s = "medium";
800 		break;
801 	case MPL_HIGH:
802 		s = "high";
803 		break;
804 	default:
805 		s = "--";
806 		break;
807 	}
808 	(void) snprintf(buf, DLADM_STRSIZE, "%s", dgettext(TEXT_DOMAIN, s));
809 	return (buf);
810 }
811 
812 void
813 dladm_free_args(dladm_arg_list_t *list)
814 {
815 	if (list != NULL) {
816 		free(list->al_buf);
817 		free(list);
818 	}
819 }
820 
821 dladm_status_t
822 dladm_parse_args(char *str, dladm_arg_list_t **listp, boolean_t novalues)
823 {
824 	dladm_arg_list_t	*list;
825 	dladm_arg_info_t	*aip;
826 	char			*buf, *curr;
827 	int			len, i;
828 
829 	list = malloc(sizeof (dladm_arg_list_t));
830 	if (list == NULL)
831 		return (dladm_errno2status(errno));
832 
833 	list->al_count = 0;
834 	list->al_buf = buf = strdup(str);
835 	if (buf == NULL)
836 		return (dladm_errno2status(errno));
837 
838 	curr = buf;
839 	len = strlen(buf);
840 	aip = NULL;
841 	for (i = 0; i < len; i++) {
842 		char		c = buf[i];
843 		boolean_t	match = (c == '=' || c == ',');
844 
845 		if (!match && i != len - 1)
846 			continue;
847 
848 		if (match) {
849 			buf[i] = '\0';
850 			if (*curr == '\0')
851 				goto fail;
852 		}
853 
854 		if (aip != NULL && c != '=') {
855 			if (aip->ai_count > DLADM_MAX_ARG_VALS)
856 				goto fail;
857 
858 			if (novalues)
859 				goto fail;
860 
861 			aip->ai_val[aip->ai_count] = curr;
862 			aip->ai_count++;
863 		} else {
864 			if (list->al_count > DLADM_MAX_ARG_VALS)
865 				goto fail;
866 
867 			aip = &list->al_info[list->al_count];
868 			aip->ai_name = curr;
869 			aip->ai_count = 0;
870 			list->al_count++;
871 			if (c == ',')
872 				aip = NULL;
873 		}
874 		curr = buf + i + 1;
875 	}
876 
877 	*listp = list;
878 	return (DLADM_STATUS_OK);
879 
880 fail:
881 	dladm_free_args(list);
882 	return (DLADM_STATUS_FAILED);
883 }
884