Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 1 | // SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-Clause) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 2 | /* |
| 3 | * libfdt - Flat Device Tree manipulation |
| 4 | * Copyright (C) 2006 David Gibson, IBM Corporation. |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 5 | */ |
| 6 | #include "libfdt_env.h" |
| 7 | |
| 8 | #include <fdt.h> |
| 9 | #include <libfdt.h> |
| 10 | |
| 11 | #include "libfdt_internal.h" |
| 12 | |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 13 | /* |
| 14 | * Minimal sanity check for a read-only tree. fdt_ro_probe_() checks |
| 15 | * that the given buffer contains what appears to be a flattened |
| 16 | * device tree with sane information in its header. |
| 17 | */ |
| 18 | int32_t fdt_ro_probe_(const void *fdt) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 19 | { |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 20 | uint32_t totalsize = fdt_totalsize(fdt); |
| 21 | |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 22 | if (fdt_magic(fdt) == FDT_MAGIC) { |
| 23 | /* Complete tree */ |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 24 | if (fdt_chk_version()) { |
| 25 | if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION) |
| 26 | return -FDT_ERR_BADVERSION; |
| 27 | if (fdt_last_comp_version(fdt) > |
| 28 | FDT_LAST_SUPPORTED_VERSION) |
| 29 | return -FDT_ERR_BADVERSION; |
| 30 | } |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 31 | } else if (fdt_magic(fdt) == FDT_SW_MAGIC) { |
| 32 | /* Unfinished sequential-write blob */ |
| 33 | if (fdt_size_dt_struct(fdt) == 0) |
| 34 | return -FDT_ERR_BADSTATE; |
| 35 | } else { |
| 36 | return -FDT_ERR_BADMAGIC; |
| 37 | } |
| 38 | |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 39 | if (totalsize < INT32_MAX) |
| 40 | return totalsize; |
| 41 | else |
| 42 | return -FDT_ERR_TRUNCATED; |
| 43 | } |
| 44 | |
| 45 | static int check_off_(uint32_t hdrsize, uint32_t totalsize, uint32_t off) |
| 46 | { |
| 47 | return (off >= hdrsize) && (off <= totalsize); |
| 48 | } |
| 49 | |
| 50 | static int check_block_(uint32_t hdrsize, uint32_t totalsize, |
| 51 | uint32_t base, uint32_t size) |
| 52 | { |
| 53 | if (!check_off_(hdrsize, totalsize, base)) |
| 54 | return 0; /* block start out of bounds */ |
| 55 | if ((base + size) < base) |
| 56 | return 0; /* overflow */ |
| 57 | if (!check_off_(hdrsize, totalsize, base + size)) |
| 58 | return 0; /* block end out of bounds */ |
| 59 | return 1; |
| 60 | } |
| 61 | |
| 62 | size_t fdt_header_size_(uint32_t version) |
| 63 | { |
| 64 | if (version <= 1) |
| 65 | return FDT_V1_SIZE; |
| 66 | else if (version <= 2) |
| 67 | return FDT_V2_SIZE; |
| 68 | else if (version <= 3) |
| 69 | return FDT_V3_SIZE; |
| 70 | else if (version <= 16) |
| 71 | return FDT_V16_SIZE; |
| 72 | else |
| 73 | return FDT_V17_SIZE; |
| 74 | } |
| 75 | |
| 76 | size_t fdt_header_size(const void *fdt) |
| 77 | { |
| 78 | return fdt_chk_version() ? fdt_header_size_(fdt_version(fdt)) : |
| 79 | FDT_V17_SIZE; |
| 80 | } |
| 81 | |
| 82 | int fdt_check_header(const void *fdt) |
| 83 | { |
| 84 | size_t hdrsize; |
| 85 | |
| 86 | if (fdt_magic(fdt) != FDT_MAGIC) |
| 87 | return -FDT_ERR_BADMAGIC; |
| 88 | if (fdt_chk_version()) { |
| 89 | if ((fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION) |
| 90 | || (fdt_last_comp_version(fdt) > |
| 91 | FDT_LAST_SUPPORTED_VERSION)) |
| 92 | return -FDT_ERR_BADVERSION; |
| 93 | if (fdt_version(fdt) < fdt_last_comp_version(fdt)) |
| 94 | return -FDT_ERR_BADVERSION; |
| 95 | } |
| 96 | hdrsize = fdt_header_size(fdt); |
| 97 | if (fdt_chk_basic()) { |
| 98 | |
| 99 | if ((fdt_totalsize(fdt) < hdrsize) |
| 100 | || (fdt_totalsize(fdt) > INT_MAX)) |
| 101 | return -FDT_ERR_TRUNCATED; |
| 102 | |
| 103 | /* Bounds check memrsv block */ |
| 104 | if (!check_off_(hdrsize, fdt_totalsize(fdt), |
| 105 | fdt_off_mem_rsvmap(fdt))) |
| 106 | return -FDT_ERR_TRUNCATED; |
| 107 | } |
| 108 | |
| 109 | if (fdt_chk_extra()) { |
| 110 | /* Bounds check structure block */ |
| 111 | if (fdt_chk_version() && fdt_version(fdt) < 17) { |
| 112 | if (!check_off_(hdrsize, fdt_totalsize(fdt), |
| 113 | fdt_off_dt_struct(fdt))) |
| 114 | return -FDT_ERR_TRUNCATED; |
| 115 | } else { |
| 116 | if (!check_block_(hdrsize, fdt_totalsize(fdt), |
| 117 | fdt_off_dt_struct(fdt), |
| 118 | fdt_size_dt_struct(fdt))) |
| 119 | return -FDT_ERR_TRUNCATED; |
| 120 | } |
| 121 | |
| 122 | /* Bounds check strings block */ |
| 123 | if (!check_block_(hdrsize, fdt_totalsize(fdt), |
| 124 | fdt_off_dt_strings(fdt), |
| 125 | fdt_size_dt_strings(fdt))) |
| 126 | return -FDT_ERR_TRUNCATED; |
| 127 | } |
| 128 | |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 129 | return 0; |
| 130 | } |
| 131 | |
| 132 | const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len) |
| 133 | { |
| 134 | unsigned absoffset = offset + fdt_off_dt_struct(fdt); |
| 135 | |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 136 | if (fdt_chk_basic()) |
| 137 | if ((absoffset < offset) |
| 138 | || ((absoffset + len) < absoffset) |
| 139 | || (absoffset + len) > fdt_totalsize(fdt)) |
| 140 | return NULL; |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 141 | |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 142 | if (!fdt_chk_version() || fdt_version(fdt) >= 0x11) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 143 | if (((offset + len) < offset) |
| 144 | || ((offset + len) > fdt_size_dt_struct(fdt))) |
| 145 | return NULL; |
| 146 | |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 147 | return fdt_offset_ptr_(fdt, offset); |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 148 | } |
| 149 | |
| 150 | uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset) |
| 151 | { |
| 152 | const fdt32_t *tagp, *lenp; |
| 153 | uint32_t tag; |
| 154 | int offset = startoffset; |
| 155 | const char *p; |
| 156 | |
| 157 | *nextoffset = -FDT_ERR_TRUNCATED; |
| 158 | tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE); |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 159 | if (fdt_chk_basic() && !tagp) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 160 | return FDT_END; /* premature end */ |
| 161 | tag = fdt32_to_cpu(*tagp); |
| 162 | offset += FDT_TAGSIZE; |
| 163 | |
| 164 | *nextoffset = -FDT_ERR_BADSTRUCTURE; |
| 165 | switch (tag) { |
| 166 | case FDT_BEGIN_NODE: |
| 167 | /* skip name */ |
| 168 | do { |
| 169 | p = fdt_offset_ptr(fdt, offset++, 1); |
| 170 | } while (p && (*p != '\0')); |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 171 | if (fdt_chk_basic() && !p) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 172 | return FDT_END; /* premature end */ |
| 173 | break; |
| 174 | |
| 175 | case FDT_PROP: |
| 176 | lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp)); |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 177 | if (fdt_chk_basic() && !lenp) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 178 | return FDT_END; /* premature end */ |
| 179 | /* skip-name offset, length and value */ |
| 180 | offset += sizeof(struct fdt_property) - FDT_TAGSIZE |
| 181 | + fdt32_to_cpu(*lenp); |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 182 | if (fdt_chk_version() && |
| 183 | fdt_version(fdt) < 0x10 && fdt32_to_cpu(*lenp) >= 8 && |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 184 | ((offset - fdt32_to_cpu(*lenp)) % 8) != 0) |
| 185 | offset += 4; |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 186 | break; |
| 187 | |
| 188 | case FDT_END: |
| 189 | case FDT_END_NODE: |
| 190 | case FDT_NOP: |
| 191 | break; |
| 192 | |
| 193 | default: |
| 194 | return FDT_END; |
| 195 | } |
| 196 | |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 197 | if (fdt_chk_basic() && |
| 198 | !fdt_offset_ptr(fdt, startoffset, offset - startoffset)) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 199 | return FDT_END; /* premature end */ |
| 200 | |
| 201 | *nextoffset = FDT_TAGALIGN(offset); |
| 202 | return tag; |
| 203 | } |
| 204 | |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 205 | int fdt_check_node_offset_(const void *fdt, int offset) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 206 | { |
| 207 | if ((offset < 0) || (offset % FDT_TAGSIZE) |
| 208 | || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE)) |
| 209 | return -FDT_ERR_BADOFFSET; |
| 210 | |
| 211 | return offset; |
| 212 | } |
| 213 | |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 214 | int fdt_check_prop_offset_(const void *fdt, int offset) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 215 | { |
| 216 | if ((offset < 0) || (offset % FDT_TAGSIZE) |
| 217 | || (fdt_next_tag(fdt, offset, &offset) != FDT_PROP)) |
| 218 | return -FDT_ERR_BADOFFSET; |
| 219 | |
| 220 | return offset; |
| 221 | } |
| 222 | |
| 223 | int fdt_next_node(const void *fdt, int offset, int *depth) |
| 224 | { |
| 225 | int nextoffset = 0; |
| 226 | uint32_t tag; |
| 227 | |
| 228 | if (offset >= 0) |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 229 | if ((nextoffset = fdt_check_node_offset_(fdt, offset)) < 0) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 230 | return nextoffset; |
| 231 | |
| 232 | do { |
| 233 | offset = nextoffset; |
| 234 | tag = fdt_next_tag(fdt, offset, &nextoffset); |
| 235 | |
| 236 | switch (tag) { |
| 237 | case FDT_PROP: |
| 238 | case FDT_NOP: |
| 239 | break; |
| 240 | |
| 241 | case FDT_BEGIN_NODE: |
| 242 | if (depth) |
| 243 | (*depth)++; |
| 244 | break; |
| 245 | |
| 246 | case FDT_END_NODE: |
| 247 | if (depth && ((--(*depth)) < 0)) |
| 248 | return nextoffset; |
| 249 | break; |
| 250 | |
| 251 | case FDT_END: |
| 252 | if ((nextoffset >= 0) |
| 253 | || ((nextoffset == -FDT_ERR_TRUNCATED) && !depth)) |
| 254 | return -FDT_ERR_NOTFOUND; |
| 255 | else |
| 256 | return nextoffset; |
| 257 | } |
| 258 | } while (tag != FDT_BEGIN_NODE); |
| 259 | |
| 260 | return offset; |
| 261 | } |
| 262 | |
| 263 | int fdt_first_subnode(const void *fdt, int offset) |
| 264 | { |
| 265 | int depth = 0; |
| 266 | |
| 267 | offset = fdt_next_node(fdt, offset, &depth); |
| 268 | if (offset < 0 || depth != 1) |
| 269 | return -FDT_ERR_NOTFOUND; |
| 270 | |
| 271 | return offset; |
| 272 | } |
| 273 | |
| 274 | int fdt_next_subnode(const void *fdt, int offset) |
| 275 | { |
| 276 | int depth = 1; |
| 277 | |
| 278 | /* |
| 279 | * With respect to the parent, the depth of the next subnode will be |
| 280 | * the same as the last. |
| 281 | */ |
| 282 | do { |
| 283 | offset = fdt_next_node(fdt, offset, &depth); |
| 284 | if (offset < 0 || depth < 1) |
| 285 | return -FDT_ERR_NOTFOUND; |
| 286 | } while (depth > 1); |
| 287 | |
| 288 | return offset; |
| 289 | } |
| 290 | |
Rob Herring | cd5f70d | 2018-05-19 14:13:53 +0200 | [diff] [blame] | 291 | const char *fdt_find_string_(const char *strtab, int tabsize, const char *s) |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 292 | { |
| 293 | int len = strlen(s) + 1; |
| 294 | const char *last = strtab + tabsize - len; |
| 295 | const char *p; |
| 296 | |
| 297 | for (p = strtab; p <= last; p++) |
| 298 | if (memcmp(p, s, len) == 0) |
| 299 | return p; |
| 300 | return NULL; |
| 301 | } |
| 302 | |
| 303 | int fdt_move(const void *fdt, void *buf, int bufsize) |
| 304 | { |
Simon Glass | a5e1a58 | 2019-10-27 09:47:42 -0600 | [diff] [blame^] | 305 | FDT_RO_PROBE(fdt); |
Tom Rini | bd39173 | 2017-09-23 12:52:44 -0400 | [diff] [blame] | 306 | |
| 307 | if (fdt_totalsize(fdt) > bufsize) |
| 308 | return -FDT_ERR_NOSPACE; |
| 309 | |
| 310 | memmove(buf, fdt, fdt_totalsize(fdt)); |
| 311 | return 0; |
| 312 | } |