1 /* $NetBSD: fdt_ro.c,v 1.1.1.3 2019/12/22 12:30:36 skrll Exp $ */
2
3 // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
4 /*
5 * libfdt - Flat Device Tree manipulation
6 * Copyright (C) 2006 David Gibson, IBM Corporation.
7 */
8 #include "libfdt_env.h"
9
10 #include <fdt.h>
11 #include <libfdt.h>
12
13 #include "libfdt_internal.h"
14
fdt_nodename_eq_(const void * fdt,int offset,const char * s,int len)15 static int fdt_nodename_eq_(const void *fdt, int offset,
16 const char *s, int len)
17 {
18 int olen;
19 const char *p = fdt_get_name(fdt, offset, &olen);
20
21 if (!p || olen < len)
22 /* short match */
23 return 0;
24
25 if (memcmp(p, s, len) != 0)
26 return 0;
27
28 if (p[len] == '\0')
29 return 1;
30 else if (!memchr(s, '@', len) && (p[len] == '@'))
31 return 1;
32 else
33 return 0;
34 }
35
fdt_get_string(const void * fdt,int stroffset,int * lenp)36 const char *fdt_get_string(const void *fdt, int stroffset, int *lenp)
37 {
38 int32_t totalsize = fdt_ro_probe_(fdt);
39 uint32_t absoffset = stroffset + fdt_off_dt_strings(fdt);
40 size_t len;
41 int err;
42 const char *s, *n;
43
44 err = totalsize;
45 if (totalsize < 0)
46 goto fail;
47
48 err = -FDT_ERR_BADOFFSET;
49 if (absoffset >= totalsize)
50 goto fail;
51 len = totalsize - absoffset;
52
53 if (fdt_magic(fdt) == FDT_MAGIC) {
54 if (stroffset < 0)
55 goto fail;
56 if (fdt_version(fdt) >= 17) {
57 if (stroffset >= fdt_size_dt_strings(fdt))
58 goto fail;
59 if ((fdt_size_dt_strings(fdt) - stroffset) < len)
60 len = fdt_size_dt_strings(fdt) - stroffset;
61 }
62 } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
63 if ((stroffset >= 0)
64 || (stroffset < -fdt_size_dt_strings(fdt)))
65 goto fail;
66 if ((-stroffset) < len)
67 len = -stroffset;
68 } else {
69 err = -FDT_ERR_INTERNAL;
70 goto fail;
71 }
72
73 s = (const char *)fdt + absoffset;
74 n = memchr(s, '\0', len);
75 if (!n) {
76 /* missing terminating NULL */
77 err = -FDT_ERR_TRUNCATED;
78 goto fail;
79 }
80
81 if (lenp)
82 *lenp = n - s;
83 return s;
84
85 fail:
86 if (lenp)
87 *lenp = err;
88 return NULL;
89 }
90
fdt_string(const void * fdt,int stroffset)91 const char *fdt_string(const void *fdt, int stroffset)
92 {
93 return fdt_get_string(fdt, stroffset, NULL);
94 }
95
fdt_string_eq_(const void * fdt,int stroffset,const char * s,int len)96 static int fdt_string_eq_(const void *fdt, int stroffset,
97 const char *s, int len)
98 {
99 int slen;
100 const char *p = fdt_get_string(fdt, stroffset, &slen);
101
102 return p && (slen == len) && (memcmp(p, s, len) == 0);
103 }
104
fdt_find_max_phandle(const void * fdt,uint32_t * phandle)105 int fdt_find_max_phandle(const void *fdt, uint32_t *phandle)
106 {
107 uint32_t max = 0;
108 int offset = -1;
109
110 while (true) {
111 uint32_t value;
112
113 offset = fdt_next_node(fdt, offset, NULL);
114 if (offset < 0) {
115 if (offset == -FDT_ERR_NOTFOUND)
116 break;
117
118 return offset;
119 }
120
121 value = fdt_get_phandle(fdt, offset);
122
123 if (value > max)
124 max = value;
125 }
126
127 if (phandle)
128 *phandle = max;
129
130 return 0;
131 }
132
fdt_generate_phandle(const void * fdt,uint32_t * phandle)133 int fdt_generate_phandle(const void *fdt, uint32_t *phandle)
134 {
135 uint32_t max;
136 int err;
137
138 err = fdt_find_max_phandle(fdt, &max);
139 if (err < 0)
140 return err;
141
142 if (max == FDT_MAX_PHANDLE)
143 return -FDT_ERR_NOPHANDLES;
144
145 if (phandle)
146 *phandle = max + 1;
147
148 return 0;
149 }
150
fdt_mem_rsv(const void * fdt,int n)151 static const struct fdt_reserve_entry *fdt_mem_rsv(const void *fdt, int n)
152 {
153 int offset = n * sizeof(struct fdt_reserve_entry);
154 int absoffset = fdt_off_mem_rsvmap(fdt) + offset;
155
156 if (absoffset < fdt_off_mem_rsvmap(fdt))
157 return NULL;
158 if (absoffset > fdt_totalsize(fdt) - sizeof(struct fdt_reserve_entry))
159 return NULL;
160 return fdt_mem_rsv_(fdt, n);
161 }
162
fdt_get_mem_rsv(const void * fdt,int n,uint64_t * address,uint64_t * size)163 int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
164 {
165 const struct fdt_reserve_entry *re;
166
167 FDT_RO_PROBE(fdt);
168 re = fdt_mem_rsv(fdt, n);
169 if (!re)
170 return -FDT_ERR_BADOFFSET;
171
172 *address = fdt64_ld(&re->address);
173 *size = fdt64_ld(&re->size);
174 return 0;
175 }
176
fdt_num_mem_rsv(const void * fdt)177 int fdt_num_mem_rsv(const void *fdt)
178 {
179 int i;
180 const struct fdt_reserve_entry *re;
181
182 for (i = 0; (re = fdt_mem_rsv(fdt, i)) != NULL; i++) {
183 if (fdt64_ld(&re->size) == 0)
184 return i;
185 }
186 return -FDT_ERR_TRUNCATED;
187 }
188
nextprop_(const void * fdt,int offset)189 static int nextprop_(const void *fdt, int offset)
190 {
191 uint32_t tag;
192 int nextoffset;
193
194 do {
195 tag = fdt_next_tag(fdt, offset, &nextoffset);
196
197 switch (tag) {
198 case FDT_END:
199 if (nextoffset >= 0)
200 return -FDT_ERR_BADSTRUCTURE;
201 else
202 return nextoffset;
203
204 case FDT_PROP:
205 return offset;
206 }
207 offset = nextoffset;
208 } while (tag == FDT_NOP);
209
210 return -FDT_ERR_NOTFOUND;
211 }
212
fdt_subnode_offset_namelen(const void * fdt,int offset,const char * name,int namelen)213 int fdt_subnode_offset_namelen(const void *fdt, int offset,
214 const char *name, int namelen)
215 {
216 int depth;
217
218 FDT_RO_PROBE(fdt);
219
220 for (depth = 0;
221 (offset >= 0) && (depth >= 0);
222 offset = fdt_next_node(fdt, offset, &depth))
223 if ((depth == 1)
224 && fdt_nodename_eq_(fdt, offset, name, namelen))
225 return offset;
226
227 if (depth < 0)
228 return -FDT_ERR_NOTFOUND;
229 return offset; /* error */
230 }
231
fdt_subnode_offset(const void * fdt,int parentoffset,const char * name)232 int fdt_subnode_offset(const void *fdt, int parentoffset,
233 const char *name)
234 {
235 return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
236 }
237
fdt_path_offset_namelen(const void * fdt,const char * path,int namelen)238 int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen)
239 {
240 const char *end = path + namelen;
241 const char *p = path;
242 int offset = 0;
243
244 FDT_RO_PROBE(fdt);
245
246 /* see if we have an alias */
247 if (*path != '/') {
248 const char *q = memchr(path, '/', end - p);
249
250 if (!q)
251 q = end;
252
253 p = fdt_get_alias_namelen(fdt, p, q - p);
254 if (!p)
255 return -FDT_ERR_BADPATH;
256 offset = fdt_path_offset(fdt, p);
257
258 p = q;
259 }
260
261 while (p < end) {
262 const char *q;
263
264 while (*p == '/') {
265 p++;
266 if (p == end)
267 return offset;
268 }
269 q = memchr(p, '/', end - p);
270 if (! q)
271 q = end;
272
273 offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
274 if (offset < 0)
275 return offset;
276
277 p = q;
278 }
279
280 return offset;
281 }
282
fdt_path_offset(const void * fdt,const char * path)283 int fdt_path_offset(const void *fdt, const char *path)
284 {
285 return fdt_path_offset_namelen(fdt, path, strlen(path));
286 }
287
fdt_get_name(const void * fdt,int nodeoffset,int * len)288 const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
289 {
290 const struct fdt_node_header *nh = fdt_offset_ptr_(fdt, nodeoffset);
291 const char *nameptr;
292 int err;
293
294 if (((err = fdt_ro_probe_(fdt)) < 0)
295 || ((err = fdt_check_node_offset_(fdt, nodeoffset)) < 0))
296 goto fail;
297
298 nameptr = nh->name;
299
300 if (fdt_version(fdt) < 0x10) {
301 /*
302 * For old FDT versions, match the naming conventions of V16:
303 * give only the leaf name (after all /). The actual tree
304 * contents are loosely checked.
305 */
306 const char *leaf;
307 leaf = strrchr(nameptr, '/');
308 if (leaf == NULL) {
309 err = -FDT_ERR_BADSTRUCTURE;
310 goto fail;
311 }
312 nameptr = leaf+1;
313 }
314
315 if (len)
316 *len = strlen(nameptr);
317
318 return nameptr;
319
320 fail:
321 if (len)
322 *len = err;
323 return NULL;
324 }
325
fdt_first_property_offset(const void * fdt,int nodeoffset)326 int fdt_first_property_offset(const void *fdt, int nodeoffset)
327 {
328 int offset;
329
330 if ((offset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
331 return offset;
332
333 return nextprop_(fdt, offset);
334 }
335
fdt_next_property_offset(const void * fdt,int offset)336 int fdt_next_property_offset(const void *fdt, int offset)
337 {
338 if ((offset = fdt_check_prop_offset_(fdt, offset)) < 0)
339 return offset;
340
341 return nextprop_(fdt, offset);
342 }
343
fdt_get_property_by_offset_(const void * fdt,int offset,int * lenp)344 static const struct fdt_property *fdt_get_property_by_offset_(const void *fdt,
345 int offset,
346 int *lenp)
347 {
348 int err;
349 const struct fdt_property *prop;
350
351 if ((err = fdt_check_prop_offset_(fdt, offset)) < 0) {
352 if (lenp)
353 *lenp = err;
354 return NULL;
355 }
356
357 prop = fdt_offset_ptr_(fdt, offset);
358
359 if (lenp)
360 *lenp = fdt32_ld(&prop->len);
361
362 return prop;
363 }
364
fdt_get_property_by_offset(const void * fdt,int offset,int * lenp)365 const struct fdt_property *fdt_get_property_by_offset(const void *fdt,
366 int offset,
367 int *lenp)
368 {
369 /* Prior to version 16, properties may need realignment
370 * and this API does not work. fdt_getprop_*() will, however. */
371
372 if (fdt_version(fdt) < 0x10) {
373 if (lenp)
374 *lenp = -FDT_ERR_BADVERSION;
375 return NULL;
376 }
377
378 return fdt_get_property_by_offset_(fdt, offset, lenp);
379 }
380
fdt_get_property_namelen_(const void * fdt,int offset,const char * name,int namelen,int * lenp,int * poffset)381 static const struct fdt_property *fdt_get_property_namelen_(const void *fdt,
382 int offset,
383 const char *name,
384 int namelen,
385 int *lenp,
386 int *poffset)
387 {
388 for (offset = fdt_first_property_offset(fdt, offset);
389 (offset >= 0);
390 (offset = fdt_next_property_offset(fdt, offset))) {
391 const struct fdt_property *prop;
392
393 if (!(prop = fdt_get_property_by_offset_(fdt, offset, lenp))) {
394 offset = -FDT_ERR_INTERNAL;
395 break;
396 }
397 if (fdt_string_eq_(fdt, fdt32_ld(&prop->nameoff),
398 name, namelen)) {
399 if (poffset)
400 *poffset = offset;
401 return prop;
402 }
403 }
404
405 if (lenp)
406 *lenp = offset;
407 return NULL;
408 }
409
410
fdt_get_property_namelen(const void * fdt,int offset,const char * name,int namelen,int * lenp)411 const struct fdt_property *fdt_get_property_namelen(const void *fdt,
412 int offset,
413 const char *name,
414 int namelen, int *lenp)
415 {
416 /* Prior to version 16, properties may need realignment
417 * and this API does not work. fdt_getprop_*() will, however. */
418 if (fdt_version(fdt) < 0x10) {
419 if (lenp)
420 *lenp = -FDT_ERR_BADVERSION;
421 return NULL;
422 }
423
424 return fdt_get_property_namelen_(fdt, offset, name, namelen, lenp,
425 NULL);
426 }
427
428
fdt_get_property(const void * fdt,int nodeoffset,const char * name,int * lenp)429 const struct fdt_property *fdt_get_property(const void *fdt,
430 int nodeoffset,
431 const char *name, int *lenp)
432 {
433 return fdt_get_property_namelen(fdt, nodeoffset, name,
434 strlen(name), lenp);
435 }
436
fdt_getprop_namelen(const void * fdt,int nodeoffset,const char * name,int namelen,int * lenp)437 const void *fdt_getprop_namelen(const void *fdt, int nodeoffset,
438 const char *name, int namelen, int *lenp)
439 {
440 int poffset;
441 const struct fdt_property *prop;
442
443 prop = fdt_get_property_namelen_(fdt, nodeoffset, name, namelen, lenp,
444 &poffset);
445 if (!prop)
446 return NULL;
447
448 /* Handle realignment */
449 if (fdt_version(fdt) < 0x10 && (poffset + sizeof(*prop)) % 8 &&
450 fdt32_ld(&prop->len) >= 8)
451 return prop->data + 4;
452 return prop->data;
453 }
454
fdt_getprop_by_offset(const void * fdt,int offset,const char ** namep,int * lenp)455 const void *fdt_getprop_by_offset(const void *fdt, int offset,
456 const char **namep, int *lenp)
457 {
458 const struct fdt_property *prop;
459
460 prop = fdt_get_property_by_offset_(fdt, offset, lenp);
461 if (!prop)
462 return NULL;
463 if (namep) {
464 const char *name;
465 int namelen;
466 name = fdt_get_string(fdt, fdt32_ld(&prop->nameoff),
467 &namelen);
468 if (!name) {
469 if (lenp)
470 *lenp = namelen;
471 return NULL;
472 }
473 *namep = name;
474 }
475
476 /* Handle realignment */
477 if (fdt_version(fdt) < 0x10 && (offset + sizeof(*prop)) % 8 &&
478 fdt32_ld(&prop->len) >= 8)
479 return prop->data + 4;
480 return prop->data;
481 }
482
fdt_getprop(const void * fdt,int nodeoffset,const char * name,int * lenp)483 const void *fdt_getprop(const void *fdt, int nodeoffset,
484 const char *name, int *lenp)
485 {
486 return fdt_getprop_namelen(fdt, nodeoffset, name, strlen(name), lenp);
487 }
488
fdt_get_phandle(const void * fdt,int nodeoffset)489 uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
490 {
491 const fdt32_t *php;
492 int len;
493
494 /* FIXME: This is a bit sub-optimal, since we potentially scan
495 * over all the properties twice. */
496 php = fdt_getprop(fdt, nodeoffset, "phandle", &len);
497 if (!php || (len != sizeof(*php))) {
498 php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
499 if (!php || (len != sizeof(*php)))
500 return 0;
501 }
502
503 return fdt32_ld(php);
504 }
505
fdt_get_alias_namelen(const void * fdt,const char * name,int namelen)506 const char *fdt_get_alias_namelen(const void *fdt,
507 const char *name, int namelen)
508 {
509 int aliasoffset;
510
511 aliasoffset = fdt_path_offset(fdt, "/aliases");
512 if (aliasoffset < 0)
513 return NULL;
514
515 return fdt_getprop_namelen(fdt, aliasoffset, name, namelen, NULL);
516 }
517
fdt_get_alias(const void * fdt,const char * name)518 const char *fdt_get_alias(const void *fdt, const char *name)
519 {
520 return fdt_get_alias_namelen(fdt, name, strlen(name));
521 }
522
fdt_get_path(const void * fdt,int nodeoffset,char * buf,int buflen)523 int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
524 {
525 int pdepth = 0, p = 0;
526 int offset, depth, namelen;
527 const char *name;
528
529 FDT_RO_PROBE(fdt);
530
531 if (buflen < 2)
532 return -FDT_ERR_NOSPACE;
533
534 for (offset = 0, depth = 0;
535 (offset >= 0) && (offset <= nodeoffset);
536 offset = fdt_next_node(fdt, offset, &depth)) {
537 while (pdepth > depth) {
538 do {
539 p--;
540 } while (buf[p-1] != '/');
541 pdepth--;
542 }
543
544 if (pdepth >= depth) {
545 name = fdt_get_name(fdt, offset, &namelen);
546 if (!name)
547 return namelen;
548 if ((p + namelen + 1) <= buflen) {
549 memcpy(buf + p, name, namelen);
550 p += namelen;
551 buf[p++] = '/';
552 pdepth++;
553 }
554 }
555
556 if (offset == nodeoffset) {
557 if (pdepth < (depth + 1))
558 return -FDT_ERR_NOSPACE;
559
560 if (p > 1) /* special case so that root path is "/", not "" */
561 p--;
562 buf[p] = '\0';
563 return 0;
564 }
565 }
566
567 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
568 return -FDT_ERR_BADOFFSET;
569 else if (offset == -FDT_ERR_BADOFFSET)
570 return -FDT_ERR_BADSTRUCTURE;
571
572 return offset; /* error from fdt_next_node() */
573 }
574
fdt_supernode_atdepth_offset(const void * fdt,int nodeoffset,int supernodedepth,int * nodedepth)575 int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
576 int supernodedepth, int *nodedepth)
577 {
578 int offset, depth;
579 int supernodeoffset = -FDT_ERR_INTERNAL;
580
581 FDT_RO_PROBE(fdt);
582
583 if (supernodedepth < 0)
584 return -FDT_ERR_NOTFOUND;
585
586 for (offset = 0, depth = 0;
587 (offset >= 0) && (offset <= nodeoffset);
588 offset = fdt_next_node(fdt, offset, &depth)) {
589 if (depth == supernodedepth)
590 supernodeoffset = offset;
591
592 if (offset == nodeoffset) {
593 if (nodedepth)
594 *nodedepth = depth;
595
596 if (supernodedepth > depth)
597 return -FDT_ERR_NOTFOUND;
598 else
599 return supernodeoffset;
600 }
601 }
602
603 if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
604 return -FDT_ERR_BADOFFSET;
605 else if (offset == -FDT_ERR_BADOFFSET)
606 return -FDT_ERR_BADSTRUCTURE;
607
608 return offset; /* error from fdt_next_node() */
609 }
610
fdt_node_depth(const void * fdt,int nodeoffset)611 int fdt_node_depth(const void *fdt, int nodeoffset)
612 {
613 int nodedepth;
614 int err;
615
616 err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
617 if (err)
618 return (err < 0) ? err : -FDT_ERR_INTERNAL;
619 return nodedepth;
620 }
621
fdt_parent_offset(const void * fdt,int nodeoffset)622 int fdt_parent_offset(const void *fdt, int nodeoffset)
623 {
624 int nodedepth = fdt_node_depth(fdt, nodeoffset);
625
626 if (nodedepth < 0)
627 return nodedepth;
628 return fdt_supernode_atdepth_offset(fdt, nodeoffset,
629 nodedepth - 1, NULL);
630 }
631
fdt_node_offset_by_prop_value(const void * fdt,int startoffset,const char * propname,const void * propval,int proplen)632 int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
633 const char *propname,
634 const void *propval, int proplen)
635 {
636 int offset;
637 const void *val;
638 int len;
639
640 FDT_RO_PROBE(fdt);
641
642 /* FIXME: The algorithm here is pretty horrible: we scan each
643 * property of a node in fdt_getprop(), then if that didn't
644 * find what we want, we scan over them again making our way
645 * to the next node. Still it's the easiest to implement
646 * approach; performance can come later. */
647 for (offset = fdt_next_node(fdt, startoffset, NULL);
648 offset >= 0;
649 offset = fdt_next_node(fdt, offset, NULL)) {
650 val = fdt_getprop(fdt, offset, propname, &len);
651 if (val && (len == proplen)
652 && (memcmp(val, propval, len) == 0))
653 return offset;
654 }
655
656 return offset; /* error from fdt_next_node() */
657 }
658
fdt_node_offset_by_phandle(const void * fdt,uint32_t phandle)659 int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
660 {
661 int offset;
662
663 if ((phandle == 0) || (phandle == -1))
664 return -FDT_ERR_BADPHANDLE;
665
666 FDT_RO_PROBE(fdt);
667
668 /* FIXME: The algorithm here is pretty horrible: we
669 * potentially scan each property of a node in
670 * fdt_get_phandle(), then if that didn't find what
671 * we want, we scan over them again making our way to the next
672 * node. Still it's the easiest to implement approach;
673 * performance can come later. */
674 for (offset = fdt_next_node(fdt, -1, NULL);
675 offset >= 0;
676 offset = fdt_next_node(fdt, offset, NULL)) {
677 if (fdt_get_phandle(fdt, offset) == phandle)
678 return offset;
679 }
680
681 return offset; /* error from fdt_next_node() */
682 }
683
fdt_stringlist_contains(const char * strlist,int listlen,const char * str)684 int fdt_stringlist_contains(const char *strlist, int listlen, const char *str)
685 {
686 int len = strlen(str);
687 const char *p;
688
689 while (listlen >= len) {
690 if (memcmp(str, strlist, len+1) == 0)
691 return 1;
692 p = memchr(strlist, '\0', listlen);
693 if (!p)
694 return 0; /* malformed strlist.. */
695 listlen -= (p-strlist) + 1;
696 strlist = p + 1;
697 }
698 return 0;
699 }
700
fdt_stringlist_count(const void * fdt,int nodeoffset,const char * property)701 int fdt_stringlist_count(const void *fdt, int nodeoffset, const char *property)
702 {
703 const char *list, *end;
704 int length, count = 0;
705
706 list = fdt_getprop(fdt, nodeoffset, property, &length);
707 if (!list)
708 return length;
709
710 end = list + length;
711
712 while (list < end) {
713 length = strnlen(list, end - list) + 1;
714
715 /* Abort if the last string isn't properly NUL-terminated. */
716 if (list + length > end)
717 return -FDT_ERR_BADVALUE;
718
719 list += length;
720 count++;
721 }
722
723 return count;
724 }
725
fdt_stringlist_search(const void * fdt,int nodeoffset,const char * property,const char * string)726 int fdt_stringlist_search(const void *fdt, int nodeoffset, const char *property,
727 const char *string)
728 {
729 int length, len, idx = 0;
730 const char *list, *end;
731
732 list = fdt_getprop(fdt, nodeoffset, property, &length);
733 if (!list)
734 return length;
735
736 len = strlen(string) + 1;
737 end = list + length;
738
739 while (list < end) {
740 length = strnlen(list, end - list) + 1;
741
742 /* Abort if the last string isn't properly NUL-terminated. */
743 if (list + length > end)
744 return -FDT_ERR_BADVALUE;
745
746 if (length == len && memcmp(list, string, length) == 0)
747 return idx;
748
749 list += length;
750 idx++;
751 }
752
753 return -FDT_ERR_NOTFOUND;
754 }
755
fdt_stringlist_get(const void * fdt,int nodeoffset,const char * property,int idx,int * lenp)756 const char *fdt_stringlist_get(const void *fdt, int nodeoffset,
757 const char *property, int idx,
758 int *lenp)
759 {
760 const char *list, *end;
761 int length;
762
763 list = fdt_getprop(fdt, nodeoffset, property, &length);
764 if (!list) {
765 if (lenp)
766 *lenp = length;
767
768 return NULL;
769 }
770
771 end = list + length;
772
773 while (list < end) {
774 length = strnlen(list, end - list) + 1;
775
776 /* Abort if the last string isn't properly NUL-terminated. */
777 if (list + length > end) {
778 if (lenp)
779 *lenp = -FDT_ERR_BADVALUE;
780
781 return NULL;
782 }
783
784 if (idx == 0) {
785 if (lenp)
786 *lenp = length - 1;
787
788 return list;
789 }
790
791 list += length;
792 idx--;
793 }
794
795 if (lenp)
796 *lenp = -FDT_ERR_NOTFOUND;
797
798 return NULL;
799 }
800
fdt_node_check_compatible(const void * fdt,int nodeoffset,const char * compatible)801 int fdt_node_check_compatible(const void *fdt, int nodeoffset,
802 const char *compatible)
803 {
804 const void *prop;
805 int len;
806
807 prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
808 if (!prop)
809 return len;
810
811 return !fdt_stringlist_contains(prop, len, compatible);
812 }
813
fdt_node_offset_by_compatible(const void * fdt,int startoffset,const char * compatible)814 int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
815 const char *compatible)
816 {
817 int offset, err;
818
819 FDT_RO_PROBE(fdt);
820
821 /* FIXME: The algorithm here is pretty horrible: we scan each
822 * property of a node in fdt_node_check_compatible(), then if
823 * that didn't find what we want, we scan over them again
824 * making our way to the next node. Still it's the easiest to
825 * implement approach; performance can come later. */
826 for (offset = fdt_next_node(fdt, startoffset, NULL);
827 offset >= 0;
828 offset = fdt_next_node(fdt, offset, NULL)) {
829 err = fdt_node_check_compatible(fdt, offset, compatible);
830 if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
831 return err;
832 else if (err == 0)
833 return offset;
834 }
835
836 return offset; /* error from fdt_next_node() */
837 }
838
fdt_check_full(const void * fdt,size_t bufsize)839 int fdt_check_full(const void *fdt, size_t bufsize)
840 {
841 int err;
842 int num_memrsv;
843 int offset, nextoffset = 0;
844 uint32_t tag;
845 unsigned depth = 0;
846 const void *prop;
847 const char *propname;
848
849 if (bufsize < FDT_V1_SIZE)
850 return -FDT_ERR_TRUNCATED;
851 err = fdt_check_header(fdt);
852 if (err != 0)
853 return err;
854 if (bufsize < fdt_totalsize(fdt))
855 return -FDT_ERR_TRUNCATED;
856
857 num_memrsv = fdt_num_mem_rsv(fdt);
858 if (num_memrsv < 0)
859 return num_memrsv;
860
861 while (1) {
862 offset = nextoffset;
863 tag = fdt_next_tag(fdt, offset, &nextoffset);
864
865 if (nextoffset < 0)
866 return nextoffset;
867
868 switch (tag) {
869 case FDT_NOP:
870 break;
871
872 case FDT_END:
873 if (depth != 0)
874 return -FDT_ERR_BADSTRUCTURE;
875 return 0;
876
877 case FDT_BEGIN_NODE:
878 depth++;
879 if (depth > INT_MAX)
880 return -FDT_ERR_BADSTRUCTURE;
881 break;
882
883 case FDT_END_NODE:
884 if (depth == 0)
885 return -FDT_ERR_BADSTRUCTURE;
886 depth--;
887 break;
888
889 case FDT_PROP:
890 prop = fdt_getprop_by_offset(fdt, offset, &propname,
891 &err);
892 if (!prop)
893 return err;
894 break;
895
896 default:
897 return -FDT_ERR_INTERNAL;
898 }
899 }
900 }
901