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

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