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 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 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 47 static inline int fdt_data_size_(void *fdt) 48 { 49 return fdt_off_dt_strings(fdt) + fdt_size_dt_strings(fdt); 50 } 51 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 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 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 */ 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 } 101 102 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 } 114 115 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 } 140 141 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 } 157 158 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 } 169 170 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 } 187 188 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 } 219 220 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 } 242 243 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 } 260 261 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 } 275 276 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 } 302 303 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 } 317 318 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 } 358 359 int fdt_add_subnode(void *fdt, int parentoffset, const char *name) 360 { 361 return fdt_add_subnode_namelen(fdt, parentoffset, name, strlen(name)); 362 } 363 364 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 } 377 378 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 } 399 400 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 } 463 464 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