xref: /illumos-gate/usr/src/common/devid/devid.c (revision 014740de)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*
28  * Copyright (c) 2018, Joyent, Inc.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/stropts.h>
33 #include <sys/debug.h>
34 #include <sys/isa_defs.h>
35 #include <sys/dditypes.h>
36 #include <sys/ddi_impldefs.h>
37 #include "devid_impl.h"
38 
39 static int devid_str_decode_id(char *devidstr, ddi_devid_t *devidp,
40     char **minor_namep, impl_devid_t *id);
41 
42 
43 /*
44  * Validate device id.
45  */
46 int
47 #ifdef	_KERNEL
48 ddi_devid_valid(ddi_devid_t devid)
49 #else	/* !_KERNEL */
50 devid_valid(ddi_devid_t devid)
51 #endif	/* _KERNEL */
52 {
53 	impl_devid_t	*id = (impl_devid_t *)devid;
54 	ushort_t	type;
55 
56 	DEVID_ASSERT(devid != NULL);
57 
58 	if (id->did_magic_hi != DEVID_MAGIC_MSB)
59 		return (DEVID_RET_INVALID);
60 
61 	if (id->did_magic_lo != DEVID_MAGIC_LSB)
62 		return (DEVID_RET_INVALID);
63 
64 	if (id->did_rev_hi != DEVID_REV_MSB)
65 		return (DEVID_RET_INVALID);
66 
67 	if (id->did_rev_lo != DEVID_REV_LSB)
68 		return (DEVID_RET_INVALID);
69 
70 	type = DEVID_GETTYPE(id);
71 	if ((type == DEVID_NONE) || (type > DEVID_MAXTYPE))
72 		return (DEVID_RET_INVALID);
73 
74 	return (DEVID_RET_VALID);
75 }
76 
77 /*
78  * Return the sizeof a device id. If called with NULL devid it returns
79  * the amount of space needed to determine the size.
80  */
81 size_t
82 #ifdef	_KERNEL
83 ddi_devid_sizeof(ddi_devid_t devid)
84 #else	/* !_KERNEL */
85 devid_sizeof(ddi_devid_t devid)
86 #endif	/* _KERNEL */
87 {
88 	impl_devid_t	*id = (impl_devid_t *)devid;
89 
90 	if (id == NULL)
91 		return (sizeof (*id) - sizeof (id->did_id));
92 
93 	DEVID_ASSERT(DEVID_FUNC(devid_valid)(devid) == DEVID_RET_VALID);
94 
95 	return (sizeof (*id) + DEVID_GETLEN(id) - sizeof (id->did_id));
96 }
97 
98 /*
99  * Compare two device id's.
100  *	-1 - less than
101  *	0  - equal
102  * 	1  - greater than
103  */
104 int
105 #ifdef	_KERNEL
106 ddi_devid_compare(ddi_devid_t id1, ddi_devid_t id2)
107 #else	/* !_KERNEL */
108 devid_compare(ddi_devid_t id1, ddi_devid_t id2)
109 #endif	/* _KERNEL */
110 {
111 	int		rval;
112 	impl_devid_t	*i_id1	= (impl_devid_t *)id1;
113 	impl_devid_t	*i_id2	= (impl_devid_t *)id2;
114 	ushort_t	i_id1_type;
115 	ushort_t	i_id2_type;
116 
117 	DEVID_ASSERT((id1 != NULL) && (id2 != NULL));
118 	DEVID_ASSERT(DEVID_FUNC(devid_valid)(id1) == DEVID_RET_VALID);
119 	DEVID_ASSERT(DEVID_FUNC(devid_valid)(id2) == DEVID_RET_VALID);
120 
121 	/* magic and revision comparison */
122 	if ((rval = bcmp(id1, id2, 4)) != 0) {
123 		return (rval);
124 	}
125 
126 	/* get current devid types */
127 	i_id1_type = DEVID_GETTYPE(i_id1);
128 	i_id2_type = DEVID_GETTYPE(i_id2);
129 
130 	/*
131 	 * Originaly all page83 devids used DEVID_SCSI3_WWN.
132 	 * To avoid a possible uniqueness issue each type of page83
133 	 * encoding supported is represented as a separate
134 	 * devid type.  If comparing DEVID_SCSI3_WWN against
135 	 * one of the new page83 encodings we assume that no
136 	 * uniqueness issue exists (since we had apparently been
137 	 * running with the old DEVID_SCSI3_WWN encoding without
138 	 * a problem).
139 	 */
140 	if ((i_id1_type == DEVID_SCSI3_WWN) ||
141 	    (i_id2_type == DEVID_SCSI3_WWN)) {
142 		/*
143 		 * Atleast one devid is using old scsi
144 		 * encode algorithm.  Force devid types
145 		 * to same scheme for comparison.
146 		 */
147 		if (IS_DEVID_SCSI3_VPD_TYPE(i_id1_type)) {
148 			i_id1_type = DEVID_SCSI3_WWN;
149 		}
150 		if (IS_DEVID_SCSI3_VPD_TYPE(i_id2_type)) {
151 			i_id2_type = DEVID_SCSI3_WWN;
152 		}
153 	}
154 
155 	/* type comparison */
156 	if (i_id1_type != i_id2_type) {
157 		return ((i_id1_type < i_id2_type) ? -1 : 1);
158 	}
159 
160 	/* length comparison */
161 	if (DEVID_GETLEN(i_id1) != DEVID_GETLEN(i_id2)) {
162 		return (DEVID_GETLEN(i_id1) < DEVID_GETLEN(i_id2) ? -1 : 1);
163 	}
164 
165 	/* id comparison */
166 	rval = bcmp(i_id1->did_id, i_id2->did_id, DEVID_GETLEN(i_id1));
167 
168 	return (rval);
169 }
170 
171 /*
172  * Free a Device Id
173  */
174 void
175 #ifdef	_KERNEL
176 ddi_devid_free(ddi_devid_t devid)
177 #else	/* !_KERNEL */
178 devid_free(ddi_devid_t devid)
179 #endif	/* _KERNEL */
180 {
181 	DEVID_ASSERT(devid != NULL);
182 	DEVID_FREE(devid, DEVID_FUNC(devid_sizeof)(devid));
183 }
184 
185 /*
186  * Encode a device id into a string.  See ddi_impldefs.h for details.
187  */
188 char *
189 #ifdef	_KERNEL
190 ddi_devid_str_encode(ddi_devid_t devid, char *minor_name)
191 #else	/* !_KERNEL */
192 devid_str_encode(ddi_devid_t devid, char *minor_name)
193 #endif	/* _KERNEL */
194 {
195 	impl_devid_t	*id = (impl_devid_t *)devid;
196 	size_t		driver_len, devid_len, slen;
197 	char		*sbuf, *dsp, *dp, ta;
198 	int		i, n, ascii;
199 
200 	/* "id0" is the encoded representation of a NULL device id */
201 	if (devid == NULL) {
202 		if ((sbuf = DEVID_MALLOC(4)) == NULL)
203 			return (NULL);
204 		*(sbuf+0) = DEVID_MAGIC_MSB;
205 		*(sbuf+1) = DEVID_MAGIC_LSB;
206 		*(sbuf+2) = '0';
207 		*(sbuf+3) = 0;
208 		return (sbuf);
209 	}
210 
211 	/* verify input */
212 	if (DEVID_FUNC(devid_valid)(devid) != DEVID_RET_VALID)
213 		return (NULL);
214 
215 	/* scan the driver hint to see how long the hint is */
216 	for (driver_len = 0; driver_len < DEVID_HINT_SIZE; driver_len++)
217 		if (id->did_driver[driver_len] == '\0')
218 			break;
219 
220 	/* scan the contained did_id to see if it meets ascii requirements */
221 	devid_len = DEVID_GETLEN(id);
222 	for (ascii = 1, i = 0; i < devid_len; i++)
223 		if (!DEVID_IDBYTE_ISASCII(id->did_id[i])) {
224 			ascii = 0;
225 			break;
226 		}
227 
228 	/* some types should always go hex even if they look ascii */
229 	if (DEVID_TYPE_BIN_FORCEHEX(id->did_type_lo))
230 		ascii = 0;
231 
232 	/* set the length of the resulting string */
233 	slen = 2 + 1;					/* <magic><rev> "id1" */
234 	slen += 1 + driver_len + 1 + 1;			/* ",<driver>@<type>" */
235 	slen += ascii ? devid_len : (devid_len * 2);	/* did_id field */
236 	if (minor_name) {
237 		slen += 1;				/* '/' */
238 		slen += strlen(minor_name);		/* len of minor_name */
239 	}
240 	slen += 1;					/* NULL */
241 
242 	/* allocate string */
243 	if ((sbuf = DEVID_MALLOC(slen)) == NULL)
244 		return (NULL);
245 
246 	/* perform encode of id to hex string */
247 	dsp = sbuf;
248 	*dsp++ = id->did_magic_hi;
249 	*dsp++ = id->did_magic_lo;
250 	*dsp++ = DEVID_REV_BINTOASCII(id->did_rev_lo);
251 	*dsp++ = ',';
252 	for (i = 0; i < driver_len; i++)
253 		*dsp++ = id->did_driver[i];
254 	*dsp++ = '@';
255 	ta = DEVID_TYPE_BINTOASCII(id->did_type_lo);
256 	if (ascii)
257 		ta = DEVID_TYPE_SETASCII(ta);
258 	*dsp++ = ta;
259 	for (i = 0, dp = &id->did_id[0]; i < devid_len; i++, dp++) {
260 		if (ascii) {
261 			if (*dp == ' ')
262 				*dsp++ = '_';
263 			else if (*dp == 0x00)
264 				*dsp++ = '~';
265 			else
266 				*dsp++ = *dp;
267 		} else {
268 			n = ((*dp) >> 4) & 0xF;
269 			*dsp++ = (n < 10) ? (n + '0') : (n + ('a' - 10));
270 			n = (*dp) & 0xF;
271 			*dsp++ = (n < 10) ? (n + '0') : (n + ('a' - 10));
272 		}
273 	}
274 
275 	if (minor_name) {
276 		*dsp++ = '/';
277 		(void) strcpy(dsp, minor_name);
278 	} else
279 		*dsp++ = 0;
280 
281 	/* ensure that (strlen + 1) is correct length for free */
282 	DEVID_ASSERT((strlen(sbuf) + 1) == slen);
283 	return (sbuf);
284 }
285 
286 /* free the string returned by devid_str_encode */
287 void
288 #ifdef	_KERNEL
289 ddi_devid_str_free(char *devidstr)
290 #else	/* !_KERNEL */
291 devid_str_free(char *devidstr)
292 #endif	/* _KERNEL */
293 {
294 	DEVID_FREE(devidstr, strlen(devidstr) + 1);
295 }
296 
297 /*
298  * given the string representation of a device id returned by calling
299  * devid_str_encode (passed in as devidstr), return pointers to the
300  * broken out devid and minor_name as requested. Devidstr remains
301  * allocated and unmodified. The devid returned in *devidp should be freed by
302  * calling devid_free.  The minor_name returned in minor_namep should
303  * be freed by calling devid_str_free(minor_namep).
304  *
305  * See ddi_impldefs.h for format details.
306  */
307 int
308 #ifdef	_KERNEL
309 ddi_devid_str_decode(
310 #else	/* !_KERNEL */
311 devid_str_decode(
312 #endif	/* _KERNEL */
313     char *devidstr, ddi_devid_t *devidp, char **minor_namep)
314 {
315 	return (devid_str_decode_id(devidstr, devidp, minor_namep, NULL));
316 }
317 
318 /* implementation for (ddi_)devid_str_decode */
319 static int
320 devid_str_decode_id(char *devidstr, ddi_devid_t *devidp,
321     char **minor_namep, impl_devid_t *id)
322 {
323 	char		*str, *msp, *dsp, *dp, ta;
324 	int		slen, devid_len, ascii, i, n, c, pre_alloc = FALSE;
325 	unsigned short	id_len, type;		/* for hibyte/lobyte */
326 
327 	devid_len = 0;
328 	if (devidp != NULL)
329 		*devidp = NULL;
330 	if (minor_namep != NULL)
331 		*minor_namep = NULL;
332 	if (id != NULL)
333 		pre_alloc = TRUE;
334 
335 	if (devidstr == NULL)
336 		return (DEVID_FAILURE);
337 
338 	/* the string must atleast contain the ascii two byte header */
339 	slen = strlen(devidstr);
340 	if ((slen < 3) || (devidstr[0] != DEVID_MAGIC_MSB) ||
341 	    (devidstr[1] != DEVID_MAGIC_LSB))
342 		return (DEVID_FAILURE);
343 
344 	/* "id0" is the encoded representation of a NULL device id */
345 	if ((devidstr[2] == '0') && (slen == 3))
346 		return (DEVID_SUCCESS);
347 
348 	/* "id1,@S0" is the shortest possible, reject if shorter */
349 	if (slen <  7)
350 		return (DEVID_FAILURE);
351 
352 	/* find the optional minor name, start after ',' */
353 	if ((msp = strchr(&devidstr[4], '/')) != NULL)
354 		msp++;
355 
356 	/* skip devid processing if we are not asked to return it */
357 	if (devidp) {
358 		/* find the required '@' separator */
359 		if ((str = strchr(devidstr, '@')) == NULL)
360 			return (DEVID_FAILURE);
361 		str++;					/* skip '@' */
362 
363 		/* pick up <type> after the '@' and verify */
364 		ta = *str++;
365 		ascii = DEVID_TYPE_ISASCII(ta);
366 		type = DEVID_TYPE_ASCIITOBIN(ta);
367 		if (type > DEVID_MAXTYPE)
368 			return (DEVID_FAILURE);
369 
370 		/* determine length of id->did_id field */
371 		if (msp == NULL)
372 			id_len = strlen(str);
373 		else
374 			id_len = msp - str - 1;
375 
376 		/* account for encoding: with hex, binary is half the size */
377 		if (!ascii) {
378 			/* hex id field must be even length */
379 			if (id_len & 1)
380 				return (DEVID_FAILURE);
381 			id_len /= 2;
382 		}
383 
384 		/* add in size of the binary devid header */
385 		devid_len = id_len + sizeof (*id) - sizeof (id->did_id);
386 
387 		/*
388 		 * Allocate space for devid if we are asked to decode it
389 		 * decode it and space wasn't pre-allocated.
390 		 */
391 		if (pre_alloc == FALSE) {
392 			if ((id = (impl_devid_t *)DEVID_MALLOC(
393 			    devid_len)) == NULL)
394 				return (DEVID_FAILURE);
395 		}
396 
397 		/* decode header portion of the string into the binary devid */
398 		dsp = devidstr;
399 		id->did_magic_hi = *dsp++;		/* <magic> "id" */
400 		id->did_magic_lo = *dsp++;
401 		id->did_rev_hi = 0;
402 		id->did_rev_lo =
403 		    DEVID_REV_ASCIITOBIN(*dsp);		/* <rev> "1" */
404 		dsp++;					/* skip "1" */
405 		dsp++;					/* skip "," */
406 		for (i = 0; i < DEVID_HINT_SIZE; i++) {	/* <driver>@ */
407 			if (*dsp == '@')
408 				break;
409 			id->did_driver[i] = *dsp++;
410 		}
411 		for (; i < DEVID_HINT_SIZE; i++)
412 			id->did_driver[i] = 0;
413 
414 		/* we must now be at the '@' */
415 		if (*dsp != '@')
416 			goto efree;
417 
418 		/* set the type and length */
419 		DEVID_FORMTYPE(id, type);
420 		DEVID_FORMLEN(id, id_len);
421 
422 		/* decode devid portion of string into the binary */
423 		for (i = 0, dsp = str, dp = &id->did_id[0];
424 		    i < id_len; i++, dp++) {
425 			if (ascii) {
426 				if (*dsp == '_')
427 					*dp = ' ';
428 				else if (*dsp == '~')
429 					*dp = 0x00;
430 				else
431 					*dp = *dsp;
432 				dsp++;
433 			} else {
434 				c = *dsp++;
435 				if (c >= '0' && c <= '9')
436 					n = (c - '0') & 0xFF;
437 				else if (c >= 'a' && c <= 'f')
438 					n = (c - ('a' - 10)) & 0xFF;
439 				else
440 					goto efree;
441 				n <<= 4;
442 				c = *dsp++;
443 				if (c >= '0' && c <= '9')
444 					n |= (c - '0') & 0xFF;
445 				else if (c >= 'a' && c <= 'f')
446 					n |= (c - ('a' - 10)) & 0xFF;
447 				else
448 					goto efree;
449 				*dp = n;
450 			}
451 		}
452 
453 		/* verify result */
454 		if (DEVID_FUNC(devid_valid)((ddi_devid_t)id) != DEVID_RET_VALID)
455 			goto efree;
456 	}
457 
458 	/* duplicate minor_name if we are asked to decode it */
459 	if (minor_namep && msp) {
460 		if ((*minor_namep = DEVID_MALLOC(strlen(msp) + 1)) == NULL)
461 			goto efree;
462 		(void) strcpy(*minor_namep, msp);
463 	}
464 
465 	/* return pointer to binary */
466 	if (devidp)
467 		*devidp = (ddi_devid_t)id;
468 	return (DEVID_SUCCESS);
469 
470 efree:
471 	if ((pre_alloc == FALSE) && (id))
472 		DEVID_FREE(id, devid_len);
473 	return (DEVID_FAILURE);
474 }
475 
476 
477 /*
478  * Compare two device id's in string form
479  *	-1 - id1 less than id2
480  *	0  - equal
481  * 	1  - id1 greater than id2
482  */
483 int
484 #ifdef	_KERNEL
485 ddi_devid_str_compare(char *id1_str, char *id2_str)
486 #else	/* !_KERNEL */
487 devid_str_compare(char *id1_str, char *id2_str)
488 #endif	/* _KERNEL */
489 {
490 	int		rval	= DEVID_FAILURE;
491 	ddi_devid_t	devid1;
492 	ddi_devid_t	devid2;
493 #ifdef	_KERNEL
494 	/* kernel use static protected by lock. */
495 	static kmutex_t	id_lock;
496 	static uchar_t	id1[sizeof (impl_devid_t) + MAXPATHLEN];
497 	static uchar_t	id2[sizeof (impl_devid_t) + MAXPATHLEN];
498 #else	/* !_KERNEL */
499 	/* userland place on stack, since malloc might fail */
500 	uchar_t		id1[sizeof (impl_devid_t) + MAXPATHLEN];
501 	uchar_t		id2[sizeof (impl_devid_t) + MAXPATHLEN];
502 #endif	/* _KERNEL */
503 
504 #ifdef	_KERNEL
505 	mutex_enter(&id_lock);
506 #endif	/* _KERNEL */
507 
508 	/*
509 	 * encode string form of devid
510 	 */
511 	if ((devid_str_decode_id(id1_str, &devid1, NULL, (impl_devid_t *)id1) ==
512 	    DEVID_SUCCESS) &&
513 	    (devid_str_decode_id(id2_str, &devid2, NULL, (impl_devid_t *)id2) ==
514 	    DEVID_SUCCESS)) {
515 		rval = DEVID_FUNC(devid_compare)(devid1, devid2);
516 	}
517 
518 #ifdef	_KERNEL
519 	mutex_exit(&id_lock);
520 #endif	/* _KERNEL */
521 
522 	return (rval);
523 }
524