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