git.sur5r.net Git - u-boot/blob - lib/efi_loader/efi_file.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI utils
   4  *
   5  *  Copyright (c) 2017 Rob Clark
   6  */
   7
   8 #include <common.h>
   9 #include <charset.h>
  10 #include <efi_loader.h>
  11 #include <malloc.h>
  12 #include <fs.h>
  13
  14 /* GUID for file system information */
  15 const efi_guid_t efi_file_system_info_guid = EFI_FILE_SYSTEM_INFO_GUID;
  16
  17 struct file_system {
  18         struct efi_simple_file_system_protocol base;
  19         struct efi_device_path *dp;
  20         struct blk_desc *desc;
  21         int part;
  22 };
  23 #define to_fs(x) container_of(x, struct file_system, base)
  24
  25 struct file_handle {
  26         struct efi_file_handle base;
  27         struct file_system *fs;
  28         loff_t offset;       /* current file position/cursor */
  29         int isdir;
  30
  31         /* for reading a directory: */
  32         struct fs_dir_stream *dirs;
  33         struct fs_dirent *dent;
  34
  35         char path[0];
  36 };
  37 #define to_fh(x) container_of(x, struct file_handle, base)
  38
  39 static const struct efi_file_handle efi_file_handle_protocol;
  40
  41 static char *basename(struct file_handle *fh)
  42 {
  43         char *s = strrchr(fh->path, '/');
  44         if (s)
  45                 return s + 1;
  46         return fh->path;
  47 }
  48
  49 static int set_blk_dev(struct file_handle *fh)
  50 {
  51         return fs_set_blk_dev_with_part(fh->fs->desc, fh->fs->part);
  52 }
  53
  54 static int is_dir(struct file_handle *fh)
  55 {
  56         struct fs_dir_stream *dirs;
  57
  58         set_blk_dev(fh);
  59         dirs = fs_opendir(fh->path);
  60         if (!dirs)
  61                 return 0;
  62
  63         fs_closedir(dirs);
  64
  65         return 1;
  66 }
  67
  68 /*
  69  * Normalize a path which may include either back or fwd slashes,
  70  * double slashes, . or .. entries in the path, etc.
  71  */
  72 static int sanitize_path(char *path)
  73 {
  74         char *p;
  75
  76         /* backslash to slash: */
  77         p = path;
  78         while ((p = strchr(p, '\\')))
  79                 *p++ = '/';
  80
  81         /* handle double-slashes: */
  82         p = path;
  83         while ((p = strstr(p, "//"))) {
  84                 char *src = p + 1;
  85                 memmove(p, src, strlen(src) + 1);
  86         }
  87
  88         /* handle extra /.'s */
  89         p = path;
  90         while ((p = strstr(p, "/."))) {
  91                 /*
  92                  * You'd be tempted to do this *after* handling ".."s
  93                  * below to avoid having to check if "/." is start of
  94                  * a "/..", but that won't have the correct results..
  95                  * for example, "/foo/./../bar" would get resolved to
  96                  * "/foo/bar" if you did these two passes in the other
  97                  * order
  98                  */
  99                 if (p[2] == '.') {
 100                         p += 2;
 101                         continue;
 102                 }
 103                 char *src = p + 2;
 104                 memmove(p, src, strlen(src) + 1);
 105         }
 106
 107         /* handle extra /..'s: */
 108         p = path;
 109         while ((p = strstr(p, "/.."))) {
 110                 char *src = p + 3;
 111
 112                 p--;
 113
 114                 /* find beginning of previous path entry: */
 115                 while (true) {
 116                         if (p < path)
 117                                 return -1;
 118                         if (*p == '/')
 119                                 break;
 120                         p--;
 121                 }
 122
 123                 memmove(p, src, strlen(src) + 1);
 124         }
 125
 126         return 0;
 127 }
 128
 129 /* NOTE: despite what you would expect, 'file_name' is actually a path.
 130  * With windoze style backlashes, ofc.
 131  */
 132 static struct efi_file_handle *file_open(struct file_system *fs,
 133                 struct file_handle *parent, s16 *file_name, u64 mode)
 134 {
 135         struct file_handle *fh;
 136         char f0[MAX_UTF8_PER_UTF16] = {0};
 137         int plen = 0;
 138         int flen = 0;
 139
 140         if (file_name) {
 141                 utf16_to_utf8((u8 *)f0, (u16 *)file_name, 1);
 142                 flen = utf16_strlen((u16 *)file_name);
 143         }
 144
 145         /* we could have a parent, but also an absolute path: */
 146         if (f0[0] == '\\') {
 147                 plen = 0;
 148         } else if (parent) {
 149                 plen = strlen(parent->path) + 1;
 150         }
 151
 152         /* +2 is for null and '/' */
 153         fh = calloc(1, sizeof(*fh) + plen + (flen * MAX_UTF8_PER_UTF16) + 2);
 154
 155         fh->base = efi_file_handle_protocol;
 156         fh->fs = fs;
 157
 158         if (parent) {
 159                 char *p = fh->path;
 160
 161                 if (plen > 0) {
 162                         strcpy(p, parent->path);
 163                         p += plen - 1;
 164                         *p++ = '/';
 165                 }
 166
 167                 utf16_to_utf8((u8 *)p, (u16 *)file_name, flen);
 168
 169                 if (sanitize_path(fh->path))
 170                         goto error;
 171
 172                 /* check if file exists: */
 173                 if (set_blk_dev(fh))
 174                         goto error;
 175
 176                 if (!((mode & EFI_FILE_MODE_CREATE) || fs_exists(fh->path)))
 177                         goto error;
 178
 179                 /* figure out if file is a directory: */
 180                 fh->isdir = is_dir(fh);
 181         } else {
 182                 fh->isdir = 1;
 183                 strcpy(fh->path, "");
 184         }
 185
 186         return &fh->base;
 187
 188 error:
 189         free(fh);
 190         return NULL;
 191 }
 192
 193 static efi_status_t EFIAPI efi_file_open(struct efi_file_handle *file,
 194                 struct efi_file_handle **new_handle,
 195                 s16 *file_name, u64 open_mode, u64 attributes)
 196 {
 197         struct file_handle *fh = to_fh(file);
 198
 199         EFI_ENTRY("%p, %p, \"%ls\", %llx, %llu", file, new_handle, file_name,
 200                   open_mode, attributes);
 201
 202         *new_handle = file_open(fh->fs, fh, file_name, open_mode);
 203         if (!*new_handle)
 204                 return EFI_EXIT(EFI_NOT_FOUND);
 205
 206         return EFI_EXIT(EFI_SUCCESS);
 207 }
 208
 209 static efi_status_t file_close(struct file_handle *fh)
 210 {
 211         fs_closedir(fh->dirs);
 212         free(fh);
 213         return EFI_SUCCESS;
 214 }
 215
 216 static efi_status_t EFIAPI efi_file_close(struct efi_file_handle *file)
 217 {
 218         struct file_handle *fh = to_fh(file);
 219         EFI_ENTRY("%p", file);
 220         return EFI_EXIT(file_close(fh));
 221 }
 222
 223 static efi_status_t EFIAPI efi_file_delete(struct efi_file_handle *file)
 224 {
 225         struct file_handle *fh = to_fh(file);
 226         EFI_ENTRY("%p", file);
 227         file_close(fh);
 228         return EFI_EXIT(EFI_WARN_DELETE_FAILURE);
 229 }
 230
 231 static efi_status_t file_read(struct file_handle *fh, u64 *buffer_size,
 232                 void *buffer)
 233 {
 234         loff_t actread;
 235
 236         if (fs_read(fh->path, (ulong)buffer, fh->offset,
 237                     *buffer_size, &actread))
 238                 return EFI_DEVICE_ERROR;
 239
 240         *buffer_size = actread;
 241         fh->offset += actread;
 242
 243         return EFI_SUCCESS;
 244 }
 245
 246 static efi_status_t dir_read(struct file_handle *fh, u64 *buffer_size,
 247                 void *buffer)
 248 {
 249         struct efi_file_info *info = buffer;
 250         struct fs_dirent *dent;
 251         unsigned int required_size;
 252
 253         if (!fh->dirs) {
 254                 assert(fh->offset == 0);
 255                 fh->dirs = fs_opendir(fh->path);
 256                 if (!fh->dirs)
 257                         return EFI_DEVICE_ERROR;
 258         }
 259
 260         /*
 261          * So this is a bit awkward.  Since fs layer is stateful and we
 262          * can't rewind an entry, in the EFI_BUFFER_TOO_SMALL case below
 263          * we might have to return without consuming the dent.. so we
 264          * have to stash it for next call.
 265          */
 266         if (fh->dent) {
 267                 dent = fh->dent;
 268                 fh->dent = NULL;
 269         } else {
 270                 dent = fs_readdir(fh->dirs);
 271         }
 272
 273
 274         if (!dent) {
 275                 /* no more files in directory: */
 276                 /* workaround shim.efi bug/quirk.. as find_boot_csv()
 277                  * loops through directory contents, it initially calls
 278                  * read w/ zero length buffer to find out how much mem
 279                  * to allocate for the EFI_FILE_INFO, then allocates,
 280                  * and then calls a 2nd time.  If we return size of
 281                  * zero the first time, it happily passes that to
 282                  * AllocateZeroPool(), and when that returns NULL it
 283                  * thinks it is EFI_OUT_OF_RESOURCES.  So on first
 284                  * call return a non-zero size:
 285                  */
 286                 if (*buffer_size == 0)
 287                         *buffer_size = sizeof(*info);
 288                 else
 289                         *buffer_size = 0;
 290                 return EFI_SUCCESS;
 291         }
 292
 293         /* check buffer size: */
 294         required_size = sizeof(*info) + 2 * (strlen(dent->name) + 1);
 295         if (*buffer_size < required_size) {
 296                 *buffer_size = required_size;
 297                 fh->dent = dent;
 298                 return EFI_BUFFER_TOO_SMALL;
 299         }
 300
 301         *buffer_size = required_size;
 302         memset(info, 0, required_size);
 303
 304         info->size = required_size;
 305         info->file_size = dent->size;
 306         info->physical_size = dent->size;
 307
 308         if (dent->type == FS_DT_DIR)
 309                 info->attribute |= EFI_FILE_DIRECTORY;
 310
 311         ascii2unicode((u16 *)info->file_name, dent->name);
 312
 313         fh->offset++;
 314
 315         return EFI_SUCCESS;
 316 }
 317
 318 static efi_status_t EFIAPI efi_file_read(struct efi_file_handle *file,
 319                                          efi_uintn_t *buffer_size, void *buffer)
 320 {
 321         struct file_handle *fh = to_fh(file);
 322         efi_status_t ret = EFI_SUCCESS;
 323         u64 bs;
 324
 325         EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
 326
 327         if (!buffer_size || !buffer) {
 328                 ret = EFI_INVALID_PARAMETER;
 329                 goto error;
 330         }
 331
 332         if (set_blk_dev(fh)) {
 333                 ret = EFI_DEVICE_ERROR;
 334                 goto error;
 335         }
 336
 337         bs = *buffer_size;
 338         if (fh->isdir)
 339                 ret = dir_read(fh, &bs, buffer);
 340         else
 341                 ret = file_read(fh, &bs, buffer);
 342         if (bs <= SIZE_MAX)
 343                 *buffer_size = bs;
 344         else
 345                 *buffer_size = SIZE_MAX;
 346
 347 error:
 348         return EFI_EXIT(ret);
 349 }
 350
 351 static efi_status_t EFIAPI efi_file_write(struct efi_file_handle *file,
 352                                           efi_uintn_t *buffer_size,
 353                                           void *buffer)
 354 {
 355         struct file_handle *fh = to_fh(file);
 356         efi_status_t ret = EFI_SUCCESS;
 357         loff_t actwrite;
 358
 359         EFI_ENTRY("%p, %p, %p", file, buffer_size, buffer);
 360
 361         if (set_blk_dev(fh)) {
 362                 ret = EFI_DEVICE_ERROR;
 363                 goto error;
 364         }
 365
 366         if (fs_write(fh->path, (ulong)buffer, fh->offset, *buffer_size,
 367                      &actwrite)) {
 368                 ret = EFI_DEVICE_ERROR;
 369                 goto error;
 370         }
 371
 372         *buffer_size = actwrite;
 373         fh->offset += actwrite;
 374
 375 error:
 376         return EFI_EXIT(ret);
 377 }
 378
 379 static efi_status_t EFIAPI efi_file_getpos(struct efi_file_handle *file,
 380                                            efi_uintn_t *pos)
 381 {
 382         struct file_handle *fh = to_fh(file);
 383
 384         EFI_ENTRY("%p, %p", file, pos);
 385
 386         if (fh->offset <= SIZE_MAX) {
 387                 *pos = fh->offset;
 388                 return EFI_EXIT(EFI_SUCCESS);
 389         } else {
 390                 return EFI_EXIT(EFI_DEVICE_ERROR);
 391         }
 392 }
 393
 394 static efi_status_t EFIAPI efi_file_setpos(struct efi_file_handle *file,
 395                 efi_uintn_t pos)
 396 {
 397         struct file_handle *fh = to_fh(file);
 398         efi_status_t ret = EFI_SUCCESS;
 399
 400         EFI_ENTRY("%p, %zu", file, pos);
 401
 402         if (fh->isdir) {
 403                 if (pos != 0) {
 404                         ret = EFI_UNSUPPORTED;
 405                         goto error;
 406                 }
 407                 fs_closedir(fh->dirs);
 408                 fh->dirs = NULL;
 409         }
 410
 411         if (pos == ~0ULL) {
 412                 loff_t file_size;
 413
 414                 if (set_blk_dev(fh)) {
 415                         ret = EFI_DEVICE_ERROR;
 416                         goto error;
 417                 }
 418
 419                 if (fs_size(fh->path, &file_size)) {
 420                         ret = EFI_DEVICE_ERROR;
 421                         goto error;
 422                 }
 423
 424                 pos = file_size;
 425         }
 426
 427         fh->offset = pos;
 428
 429 error:
 430         return EFI_EXIT(ret);
 431 }
 432
 433 static efi_status_t EFIAPI efi_file_getinfo(struct efi_file_handle *file,
 434                                             const efi_guid_t *info_type,
 435                                             efi_uintn_t *buffer_size,
 436                                             void *buffer)
 437 {
 438         struct file_handle *fh = to_fh(file);
 439         efi_status_t ret = EFI_SUCCESS;
 440
 441         EFI_ENTRY("%p, %p, %p, %p", file, info_type, buffer_size, buffer);
 442
 443         if (!guidcmp(info_type, &efi_file_info_guid)) {
 444                 struct efi_file_info *info = buffer;
 445                 char *filename = basename(fh);
 446                 unsigned int required_size;
 447                 loff_t file_size;
 448
 449                 /* check buffer size: */
 450                 required_size = sizeof(*info) + 2 * (strlen(filename) + 1);
 451                 if (*buffer_size < required_size) {
 452                         *buffer_size = required_size;
 453                         ret = EFI_BUFFER_TOO_SMALL;
 454                         goto error;
 455                 }
 456
 457                 if (set_blk_dev(fh)) {
 458                         ret = EFI_DEVICE_ERROR;
 459                         goto error;
 460                 }
 461
 462                 if (fs_size(fh->path, &file_size)) {
 463                         ret = EFI_DEVICE_ERROR;
 464                         goto error;
 465                 }
 466
 467                 memset(info, 0, required_size);
 468
 469                 info->size = required_size;
 470                 info->file_size = file_size;
 471                 info->physical_size = file_size;
 472
 473                 if (fh->isdir)
 474                         info->attribute |= EFI_FILE_DIRECTORY;
 475
 476                 ascii2unicode((u16 *)info->file_name, filename);
 477         } else if (!guidcmp(info_type, &efi_file_system_info_guid)) {
 478                 struct efi_file_system_info *info = buffer;
 479                 disk_partition_t part;
 480                 efi_uintn_t required_size;
 481                 int r;
 482
 483                 if (fh->fs->part >= 1)
 484                         r = part_get_info(fh->fs->desc, fh->fs->part, &part);
 485                 else
 486                         r = part_get_info_whole_disk(fh->fs->desc, &part);
 487                 if (r < 0) {
 488                         ret = EFI_DEVICE_ERROR;
 489                         goto error;
 490                 }
 491                 required_size = sizeof(info) + 2 *
 492                                 (strlen((const char *)part.name) + 1);
 493                 if (*buffer_size < required_size) {
 494                         *buffer_size = required_size;
 495                         ret = EFI_BUFFER_TOO_SMALL;
 496                         goto error;
 497                 }
 498
 499                 memset(info, 0, required_size);
 500
 501                 info->size = required_size;
 502                 info->read_only = true;
 503                 info->volume_size = part.size * part.blksz;
 504                 info->free_space = 0;
 505                 info->block_size = part.blksz;
 506                 /*
 507                  * TODO: The volume label is not available in U-Boot.
 508                  * Use the partition name as substitute.
 509                  */
 510                 ascii2unicode((u16 *)info->volume_label,
 511                               (const char *)part.name);
 512         } else {
 513                 ret = EFI_UNSUPPORTED;
 514         }
 515
 516 error:
 517         return EFI_EXIT(ret);
 518 }
 519
 520 static efi_status_t EFIAPI efi_file_setinfo(struct efi_file_handle *file,
 521                                             const efi_guid_t *info_type,
 522                                             efi_uintn_t buffer_size,
 523                                             void *buffer)
 524 {
 525         EFI_ENTRY("%p, %p, %zu, %p", file, info_type, buffer_size, buffer);
 526
 527         return EFI_EXIT(EFI_UNSUPPORTED);
 528 }
 529
 530 static efi_status_t EFIAPI efi_file_flush(struct efi_file_handle *file)
 531 {
 532         EFI_ENTRY("%p", file);
 533         return EFI_EXIT(EFI_SUCCESS);
 534 }
 535
 536 static const struct efi_file_handle efi_file_handle_protocol = {
 537         .rev = EFI_FILE_PROTOCOL_REVISION,
 538         .open = efi_file_open,
 539         .close = efi_file_close,
 540         .delete = efi_file_delete,
 541         .read = efi_file_read,
 542         .write = efi_file_write,
 543         .getpos = efi_file_getpos,
 544         .setpos = efi_file_setpos,
 545         .getinfo = efi_file_getinfo,
 546         .setinfo = efi_file_setinfo,
 547         .flush = efi_file_flush,
 548 };
 549
 550 struct efi_file_handle *efi_file_from_path(struct efi_device_path *fp)
 551 {
 552         struct efi_simple_file_system_protocol *v;
 553         struct efi_file_handle *f;
 554         efi_status_t ret;
 555
 556         v = efi_fs_from_path(fp);
 557         if (!v)
 558                 return NULL;
 559
 560         EFI_CALL(ret = v->open_volume(v, &f));
 561         if (ret != EFI_SUCCESS)
 562                 return NULL;
 563
 564         /* skip over device-path nodes before the file path: */
 565         while (fp && !EFI_DP_TYPE(fp, MEDIA_DEVICE, FILE_PATH))
 566                 fp = efi_dp_next(fp);
 567
 568         while (fp) {
 569                 struct efi_device_path_file_path *fdp =
 570                         container_of(fp, struct efi_device_path_file_path, dp);
 571                 struct efi_file_handle *f2;
 572
 573                 if (!EFI_DP_TYPE(fp, MEDIA_DEVICE, FILE_PATH)) {
 574                         printf("bad file path!\n");
 575                         f->close(f);
 576                         return NULL;
 577                 }
 578
 579                 EFI_CALL(ret = f->open(f, &f2, (s16 *)fdp->str,
 580                                        EFI_FILE_MODE_READ, 0));
 581                 if (ret != EFI_SUCCESS)
 582                         return NULL;
 583
 584                 fp = efi_dp_next(fp);
 585
 586                 EFI_CALL(f->close(f));
 587                 f = f2;
 588         }
 589
 590         return f;
 591 }
 592
 593 static efi_status_t EFIAPI
 594 efi_open_volume(struct efi_simple_file_system_protocol *this,
 595                 struct efi_file_handle **root)
 596 {
 597         struct file_system *fs = to_fs(this);
 598
 599         EFI_ENTRY("%p, %p", this, root);
 600
 601         *root = file_open(fs, NULL, NULL, 0);
 602
 603         return EFI_EXIT(EFI_SUCCESS);
 604 }
 605
 606 struct efi_simple_file_system_protocol *
 607 efi_simple_file_system(struct blk_desc *desc, int part,
 608                        struct efi_device_path *dp)
 609 {
 610         struct file_system *fs;
 611
 612         fs = calloc(1, sizeof(*fs));
 613         fs->base.rev = EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_REVISION;
 614         fs->base.open_volume = efi_open_volume;
 615         fs->desc = desc;
 616         fs->part = part;
 617         fs->dp = dp;
 618
 619         return &fs->base;
 620 }