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1// SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause)
2/*
3 * libfdt - Flat Device Tree manipulation
4 * Copyright (C) 2006 David Gibson, IBM Corporation.
5 */
6#include "libfdt_env.h"
7
8#include <fdt.h>
9#include <libfdt.h>
10
11#include "libfdt_internal.h"
12
13static int fdt_blocks_misordered_(const void *fdt,
14 int mem_rsv_size, int struct_size)
15{
16 return (fdt_off_mem_rsvmap(fdt) < FDT_ALIGN(sizeof(struct fdt_header), 8))
17 || (fdt_off_dt_struct(fdt) <
18 (fdt_off_mem_rsvmap(fdt) + mem_rsv_size))
19 || (fdt_off_dt_strings(fdt) <
20 (fdt_off_dt_struct(fdt) + struct_size))
21 || (fdt_totalsize(fdt) <
22 (fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt)));
23}
24
25static void fdt_downgrade_version(void *fdt)
26{
27 if (!can_assume(LATEST) && fdt_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
28 fdt_set_version(fdt, FDT_LAST_SUPPORTED_VERSION);
29}
30
31static int fdt_rw_probe_(void *fdt)
32{
33 if (can_assume(VALID_DTB))
34 return 0;
35 FDT_RO_PROBE(fdt);
36
37 if (!can_assume(LATEST) && fdt_version(fdt) < 17)
38 return -FDT_ERR_BADVERSION;
39 if (fdt_blocks_misordered_(fdt, sizeof(struct fdt_reserve_entry),
40 fdt_size_dt_struct(fdt)))
41 return -FDT_ERR_BADLAYOUT;
42
43 fdt_downgrade_version(fdt);
44 return 0;
45}
46
47#define FDT_RW_PROBE(fdt) \
48 { \
49 int err_; \
50 if ((err_ = fdt_rw_probe_(fdt)) != 0) \
51 return err_; \
52 }
53
54static inline unsigned int fdt_data_size_(void *fdt)
55{
56 return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
57}
58
59static int fdt_splice_(void *fdt, void *splicepoint, int oldlen, int newlen)
60{
61 char *p = splicepoint;
62 unsigned int dsize = fdt_data_size_(fdt);
63 size_t soff = p - (char *)fdt;
64
65 if ((oldlen < 0) || (soff + oldlen < soff) || (soff + oldlen > dsize))
66 return -FDT_ERR_BADOFFSET;
67 if ((p < (char *)fdt) || (dsize + newlen < (unsigned)oldlen))
68 return -FDT_ERR_BADOFFSET;
69 if (dsize - oldlen + newlen > fdt_totalsize(fdt))
70 return -FDT_ERR_NOSPACE;
71 memmove(p + newlen, p + oldlen, ((char *)fdt + dsize) - (p + oldlen));
72 return 0;
73}
74
75static int fdt_splice_mem_rsv_(void *fdt, struct fdt_reserve_entry *p,
76 int oldn, int newn)
77{
78 int delta = (newn - oldn) * sizeof(*p);
79 int err;
80 err = fdt_splice_(fdt, p, oldn * sizeof(*p), newn * sizeof(*p));
81 if (err)
82 return err;
83 fdt_set_off_dt_struct(fdt, fdt_off_dt_struct(fdt) + delta);
84 fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
85 return 0;
86}
87
88static int fdt_splice_struct_(void *fdt, void *p,
89 int oldlen, int newlen)
90{
91 int delta = newlen - oldlen;
92 int err;
93
94 if ((err = fdt_splice_(fdt, p, oldlen, newlen)))
95 return err;
96
97 fdt_set_size_dt_struct(fdt, fdt_size_dt_struct(fdt) + delta);
98 fdt_set_off_dt_strings(fdt, fdt_off_dt_strings(fdt) + delta);
99 return 0;
100}
101
102/* Must only be used to roll back in case of error */
103static void fdt_del_last_string_(void *fdt, const char *s)
104{
105 int newlen = strlen(s) + 1;
106
107 fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) - newlen);
108}
109
110static int fdt_splice_string_(void *fdt, int newlen)
111{
112 void *p = (char *)fdt
113 + fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt);
114 int err;
115
116 if ((err = fdt_splice_(fdt, p, 0, newlen)))
117 return err;
118
119 fdt_set_size_dt_strings(fdt, fdt_size_dt_strings(fdt) + newlen);
120 return 0;
121}
122
123/**
124 * fdt_find_add_string_() - Find or allocate a string
125 *
126 * @fdt: pointer to the device tree to check/adjust
127 * @s: string to find/add
128 * @allocated: Set to 0 if the string was found, 1 if not found and so
129 * allocated. Ignored if can_assume(NO_ROLLBACK)
130 * @return offset of string in the string table (whether found or added)
131 */
132static int fdt_find_add_string_(void *fdt, const char *s, int slen,
133 int *allocated)
134{
135 char *strtab = (char *)fdt + fdt_off_dt_strings(fdt);
136 const char *p;
137 char *new;
138 int err;
139
140 if (!can_assume(NO_ROLLBACK))
141 *allocated = 0;
142
143 p = fdt_find_string_len_(strtab, fdt_size_dt_strings(fdt), s, slen);
144 if (p)
145 /* found it */
146 return (p - strtab);
147
148 new = strtab + fdt_size_dt_strings(fdt);
149 err = fdt_splice_string_(fdt, slen + 1);
150 if (err)
151 return err;
152
153 if (!can_assume(NO_ROLLBACK))
154 *allocated = 1;
155
156 memcpy(new, s, slen);
157 new[slen] = '\0';
158
159 return (new - strtab);
160}
161
162int fdt_add_mem_rsv(void *fdt, uint64_t address, uint64_t size)
163{
164 struct fdt_reserve_entry *re;
165 int err;
166
167 FDT_RW_PROBE(fdt);
168
169 re = fdt_mem_rsv_w_(fdt, fdt_num_mem_rsv(fdt));
170 err = fdt_splice_mem_rsv_(fdt, re, 0, 1);
171 if (err)
172 return err;
173
174 re->address = cpu_to_fdt64(address);
175 re->size = cpu_to_fdt64(size);
176 return 0;
177}
178
179int fdt_del_mem_rsv(void *fdt, int n)
180{
181 struct fdt_reserve_entry *re = fdt_mem_rsv_w_(fdt, n);
182
183 FDT_RW_PROBE(fdt);
184
185 if (n >= fdt_num_mem_rsv(fdt))
186 return -FDT_ERR_NOTFOUND;
187
188 return fdt_splice_mem_rsv_(fdt, re, 1, 0);
189}
190
191static int fdt_resize_property_(void *fdt, int nodeoffset,
192 const char *name, int namelen,
193 int len, struct fdt_property **prop)
194{
195 int oldlen;
196 int err;
197
198 *prop = fdt_get_property_namelen_w(fdt, nodeoffset, name, namelen,
199 &oldlen);
200 if (!*prop)
201 return oldlen;
202
203 if ((err = fdt_splice_struct_(fdt, (*prop)->data, FDT_TAGALIGN(oldlen),
204 FDT_TAGALIGN(len))))
205 return err;
206
207 (*prop)->len = cpu_to_fdt32(len);
208 return 0;
209}
210
211static int fdt_add_property_(void *fdt, int nodeoffset, const char *name,
212 int namelen, int len, struct fdt_property **prop)
213{
214 int proplen;
215 int nextoffset;
216 int namestroff;
217 int err;
218 int allocated;
219
220 if ((nextoffset = fdt_check_node_offset_(fdt, nodeoffset)) < 0)
221 return nextoffset;
222
223 namestroff = fdt_find_add_string_(fdt, name, namelen, &allocated);
224 if (namestroff < 0)
225 return namestroff;
226
227 *prop = fdt_offset_ptr_w_(fdt, nextoffset);
228 proplen = sizeof(**prop) + FDT_TAGALIGN(len);
229
230 err = fdt_splice_struct_(fdt, *prop, 0, proplen);
231 if (err) {
232 /* Delete the string if we failed to add it */
233 if (!can_assume(NO_ROLLBACK) && allocated)
234 fdt_del_last_string_(fdt, name);
235 return err;
236 }
237
238 (*prop)->tag = cpu_to_fdt32(FDT_PROP);
239 (*prop)->nameoff = cpu_to_fdt32(namestroff);
240 (*prop)->len = cpu_to_fdt32(len);
241 return 0;
242}
243
244int fdt_set_name(void *fdt, int nodeoffset, const char *name)
245{
246 char *namep;
247 int oldlen, newlen;
248 int err;
249
250 FDT_RW_PROBE(fdt);
251
252 namep = (char *)(uintptr_t)fdt_get_name(fdt, nodeoffset, &oldlen);
253 if (!namep)
254 return oldlen;
255
256 newlen = strlen(name);
257
258 err = fdt_splice_struct_(fdt, namep, FDT_TAGALIGN(oldlen+1),
259 FDT_TAGALIGN(newlen+1));
260 if (err)
261 return err;
262
263 memcpy(namep, name, newlen+1);
264 return 0;
265}
266
267int fdt_setprop_placeholder_namelen(void *fdt, int nodeoffset, const char *name,
268 int namelen, int len, void **prop_data)
269{
270 struct fdt_property *prop;
271 int err;
272
273 FDT_RW_PROBE(fdt);
274
275 err = fdt_resize_property_(fdt, nodeoffset, name, namelen, len, &prop);
276 if (err == -FDT_ERR_NOTFOUND)
277 err = fdt_add_property_(fdt, nodeoffset, name, namelen, len,
278 &prop);
279 if (err)
280 return err;
281
282 *prop_data = prop->data;
283 return 0;
284}
285
286int fdt_setprop_namelen(void *fdt, int nodeoffset, const char *name,
287 int namelen, const void *val, int len)
288{
289 void *prop_data;
290 int err;
291
292 err = fdt_setprop_placeholder_namelen(fdt, nodeoffset, name, namelen,
293 len, &prop_data);
294 if (err)
295 return err;
296
297 if (len)
298 memcpy(prop_data, val, len);
299 return 0;
300}
301
302int fdt_appendprop(void *fdt, int nodeoffset, const char *name,
303 const void *val, int len)
304{
305 struct fdt_property *prop;
306 int err, oldlen, newlen;
307
308 FDT_RW_PROBE(fdt);
309
310 prop = fdt_get_property_w(fdt, nodeoffset, name, &oldlen);
311 if (prop) {
312 newlen = len + oldlen;
313 err = fdt_splice_struct_(fdt, prop->data,
314 FDT_TAGALIGN(oldlen),
315 FDT_TAGALIGN(newlen));
316 if (err)
317 return err;
318 prop->len = cpu_to_fdt32(newlen);
319 memcpy(prop->data + oldlen, val, len);
320 } else {
321 err = fdt_add_property_(fdt, nodeoffset, name, strlen(name),
322 len, &prop);
323 if (err)
324 return err;
325 memcpy(prop->data, val, len);
326 }
327 return 0;
328}
329
330int fdt_delprop(void *fdt, int nodeoffset, const char *name)
331{
332 struct fdt_property *prop;
333 int len, proplen;
334
335 FDT_RW_PROBE(fdt);
336
337 prop = fdt_get_property_w(fdt, nodeoffset, name, &len);
338 if (!prop)
339 return len;
340
341 proplen = sizeof(*prop) + FDT_TAGALIGN(len);
342 return fdt_splice_struct_(fdt, prop, proplen, 0);
343}
344
345int fdt_add_subnode_namelen(void *fdt, int parentoffset,
346 const char *name, int namelen)
347{
348 struct fdt_node_header *nh;
349 int offset, nextoffset;
350 int nodelen;
351 int err;
352 uint32_t tag;
353 fdt32_t *endtag;
354
355 FDT_RW_PROBE(fdt);
356
357 offset = fdt_subnode_offset_namelen(fdt, parentoffset, name, namelen);
358 if (offset >= 0)
359 return -FDT_ERR_EXISTS;
360 else if (offset != -FDT_ERR_NOTFOUND)
361 return offset;
362
363 /* Try to place the new node after the parent's properties */
364 tag = fdt_next_tag(fdt, parentoffset, &nextoffset);
365 /* the fdt_subnode_offset_namelen() should ensure this never hits */
366 if (!can_assume(LIBFDT_FLAWLESS) && (tag != FDT_BEGIN_NODE))
367 return -FDT_ERR_INTERNAL;
368 do {
369 offset = nextoffset;
370 tag = fdt_next_tag(fdt, offset, &nextoffset);
371 } while ((tag == FDT_PROP) || (tag == FDT_NOP));
372
373 nh = fdt_offset_ptr_w_(fdt, offset);
374 nodelen = sizeof(*nh) + FDT_TAGALIGN(namelen+1) + FDT_TAGSIZE;
375
376 err = fdt_splice_struct_(fdt, nh, 0, nodelen);
377 if (err)
378 return err;
379
380 nh->tag = cpu_to_fdt32(FDT_BEGIN_NODE);
381 memset(nh->name, 0, FDT_TAGALIGN(namelen+1));
382 memcpy(nh->name, name, namelen);
383 endtag = (fdt32_t *)((char *)nh + nodelen - FDT_TAGSIZE);
384 *endtag = cpu_to_fdt32(FDT_END_NODE);
385
386 return offset;
387}
388
389int fdt_add_subnode(void *fdt, int parentoffset, const char *name)
390{
391 return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name));
392}
393
394int fdt_del_node(void *fdt, int nodeoffset)
395{
396 int endoffset;
397
398 FDT_RW_PROBE(fdt);
399
400 endoffset = fdt_node_end_offset_(fdt, nodeoffset);
401 if (endoffset < 0)
402 return endoffset;
403
404 return fdt_splice_struct_(fdt, fdt_offset_ptr_w_(fdt, nodeoffset),
405 endoffset - nodeoffset, 0);
406}
407
408static void fdt_packblocks_(const char *old, char *new,
409 int mem_rsv_size,
410 int struct_size,
411 int strings_size)
412{
413 int mem_rsv_off, struct_off, strings_off;
414
415 mem_rsv_off = FDT_ALIGN(sizeof(struct fdt_header), 8);
416 struct_off = mem_rsv_off + mem_rsv_size;
417 strings_off = struct_off + struct_size;
418
419 memmove(new + mem_rsv_off, old + fdt_off_mem_rsvmap(old), mem_rsv_size);
420 fdt_set_off_mem_rsvmap(new, mem_rsv_off);
421
422 memmove(new + struct_off, old + fdt_off_dt_struct(old), struct_size);
423 fdt_set_off_dt_struct(new, struct_off);
424 fdt_set_size_dt_struct(new, struct_size);
425
426 memmove(new + strings_off, old + fdt_off_dt_strings(old), strings_size);
427 fdt_set_off_dt_strings(new, strings_off);
428 fdt_set_size_dt_strings(new, fdt_size_dt_strings(old));
429}
430
431int fdt_open_into(const void *fdt, void *buf, int bufsize)
432{
433 int err;
434 int mem_rsv_size, struct_size;
435 int newsize;
436 const char *fdtstart = fdt;
437 const char *fdtend = fdtstart + fdt_totalsize(fdt);
438 char *tmp;
439
440 FDT_RO_PROBE(fdt);
441
442 mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
443 * sizeof(struct fdt_reserve_entry);
444
445 if (can_assume(LATEST) || fdt_version(fdt) >= 17) {
446 struct_size = fdt_size_dt_struct(fdt);
447 } else if (fdt_version(fdt) == 16) {
448 struct_size = 0;
449 while (fdt_next_tag(fdt, struct_size, &struct_size) != FDT_END)
450 ;
451 if (struct_size < 0)
452 return struct_size;
453 } else {
454 return -FDT_ERR_BADVERSION;
455 }
456
457 if (can_assume(LIBFDT_ORDER) ||
458 !fdt_blocks_misordered_(fdt, mem_rsv_size, struct_size)) {
459 /* no further work necessary */
460 err = fdt_move(fdt, buf, bufsize);
461 if (err)
462 return err;
463 fdt_set_version(buf, 17);
464 fdt_set_size_dt_struct(buf, struct_size);
465 fdt_set_totalsize(buf, bufsize);
466 return 0;
467 }
468
469 /* Need to reorder */
470 newsize = FDT_ALIGN(sizeof(struct fdt_header), 8) + mem_rsv_size
471 + struct_size + fdt_size_dt_strings(fdt);
472
473 if (bufsize < newsize)
474 return -FDT_ERR_NOSPACE;
475
476 /* First attempt to build converted tree at beginning of buffer */
477 tmp = buf;
478 /* But if that overlaps with the old tree... */
479 if (((tmp + newsize) > fdtstart) && (tmp < fdtend)) {
480 /* Try right after the old tree instead */
481 tmp = (char *)(uintptr_t)fdtend;
482 if ((tmp + newsize) > ((char *)buf + bufsize))
483 return -FDT_ERR_NOSPACE;
484 }
485
486 fdt_packblocks_(fdt, tmp, mem_rsv_size, struct_size,
487 fdt_size_dt_strings(fdt));
488 memmove(buf, tmp, newsize);
489
490 fdt_set_magic(buf, FDT_MAGIC);
491 fdt_set_totalsize(buf, bufsize);
492 fdt_set_version(buf, 17);
493 fdt_set_last_comp_version(buf, 16);
494 fdt_set_boot_cpuid_phys(buf, fdt_boot_cpuid_phys(fdt));
495
496 return 0;
497}
498
499int fdt_pack(void *fdt)
500{
501 int mem_rsv_size;
502
503 FDT_RW_PROBE(fdt);
504
505 mem_rsv_size = (fdt_num_mem_rsv(fdt)+1)
506 * sizeof(struct fdt_reserve_entry);
507 fdt_packblocks_(fdt, fdt, mem_rsv_size, fdt_size_dt_struct(fdt),
508 fdt_size_dt_strings(fdt));
509 fdt_set_totalsize(fdt, fdt_data_size_(fdt));
510
511 return 0;
512}