cmd/bootefi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI application loader
   4  *
   5  *  Copyright (c) 2016 Alexander Graf
   6  */
   7
   8 #include <common.h>
   9 #include <bootm.h>
  10 #include <charset.h>
  11 #include <command.h>
  12 #include <dm.h>
  13 #include <efi_loader.h>
  14 #include <efi_selftest.h>
  15 #include <errno.h>
  16 #include <linux/libfdt.h>
  17 #include <linux/libfdt_env.h>
  18 #include <mapmem.h>
  19 #include <memalign.h>
  20 #include <asm/global_data.h>
  21 #include <asm-generic/sections.h>
  22 #include <asm-generic/unaligned.h>
  23 #include <linux/linkage.h>
  24
  25 DECLARE_GLOBAL_DATA_PTR;
  26
  27 static struct efi_device_path *bootefi_image_path;
  28 static struct efi_device_path *bootefi_device_path;
  29
  30 /*
  31  * Allow unaligned memory access.
  32  *
  33  * This routine is overridden by architectures providing this feature.
  34  */
  35 void __weak allow_unaligned(void)
  36 {
  37 }
  38
  39 /*
  40  * Set the load options of an image from an environment variable.
  41  *
  42  * @loaded_image_info:  the image
  43  * @env_var:            name of the environment variable
  44  */
  45 static void set_load_options(struct efi_loaded_image *loaded_image_info,
  46                              const char *env_var)
  47 {
  48         size_t size;
  49         const char *env = env_get(env_var);
  50         u16 *pos;
  51
  52         loaded_image_info->load_options = NULL;
  53         loaded_image_info->load_options_size = 0;
  54         if (!env)
  55                 return;
  56         size = utf8_utf16_strlen(env) + 1;
  57         loaded_image_info->load_options = calloc(size, sizeof(u16));
  58         if (!loaded_image_info->load_options) {
  59                 printf("ERROR: Out of memory\n");
  60                 return;
  61         }
  62         pos = loaded_image_info->load_options;
  63         utf8_utf16_strcpy(&pos, env);
  64         loaded_image_info->load_options_size = size * 2;
  65 }
  66
  67 /**
  68  * copy_fdt() - Copy the device tree to a new location available to EFI
  69  *
  70  * The FDT is copied to a suitable location within the EFI memory map.
  71  * Additional 12 KiB are added to the space in case the device tree needs to be
  72  * expanded later with fdt_open_into().
  73  *
  74  * @fdtp:       On entry a pointer to the flattened device tree.
  75  *              On exit a pointer to the copy of the flattened device tree.
  76  *              FDT start
  77  * Return:      status code
  78  */
  79 static efi_status_t copy_fdt(void **fdtp)
  80 {
  81         unsigned long fdt_ram_start = -1L, fdt_pages;
  82         efi_status_t ret = 0;
  83         void *fdt, *new_fdt;
  84         u64 new_fdt_addr;
  85         uint fdt_size;
  86         int i;
  87
  88         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
  89                 u64 ram_start = gd->bd->bi_dram[i].start;
  90                 u64 ram_size = gd->bd->bi_dram[i].size;
  91
  92                 if (!ram_size)
  93                         continue;
  94
  95                 if (ram_start < fdt_ram_start)
  96                         fdt_ram_start = ram_start;
  97         }
  98
  99         /*
 100          * Give us at least 12 KiB of breathing room in case the device tree
 101          * needs to be expanded later.
 102          */
 103         fdt = *fdtp;
 104         fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
 105         fdt_size = fdt_pages << EFI_PAGE_SHIFT;
 106
 107         /*
 108          * Safe fdt location is at 127 MiB.
 109          * On the sandbox convert from the sandbox address space.
 110          */
 111         new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
 112                                              fdt_size, 0);
 113         ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 114                                  EFI_RUNTIME_SERVICES_DATA, fdt_pages,
 115                                  &new_fdt_addr);
 116         if (ret != EFI_SUCCESS) {
 117                 /* If we can't put it there, put it somewhere */
 118                 new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
 119                 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 120                                          EFI_RUNTIME_SERVICES_DATA, fdt_pages,
 121                                          &new_fdt_addr);
 122                 if (ret != EFI_SUCCESS) {
 123                         printf("ERROR: Failed to reserve space for FDT\n");
 124                         goto done;
 125                 }
 126         }
 127         new_fdt = (void *)(uintptr_t)new_fdt_addr;
 128         memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 129         fdt_set_totalsize(new_fdt, fdt_size);
 130
 131         *fdtp = (void *)(uintptr_t)new_fdt_addr;
 132 done:
 133         return ret;
 134 }
 135
 136 static efi_status_t efi_do_enter(
 137                         efi_handle_t image_handle, struct efi_system_table *st,
 138                         EFIAPI efi_status_t (*entry)(
 139                                 efi_handle_t image_handle,
 140                                 struct efi_system_table *st))
 141 {
 142         efi_status_t ret = EFI_LOAD_ERROR;
 143
 144         if (entry)
 145                 ret = entry(image_handle, st);
 146         st->boottime->exit(image_handle, ret, 0, NULL);
 147         return ret;
 148 }
 149
 150 /*
 151  * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
 152  *
 153  * The mem_rsv entries of the FDT are added to the memory map. Any failures are
 154  * ignored because this is not critical and we would rather continue to try to
 155  * boot.
 156  *
 157  * @fdt: Pointer to device tree
 158  */
 159 static void efi_carve_out_dt_rsv(void *fdt)
 160 {
 161         int nr_rsv, i;
 162         uint64_t addr, size, pages;
 163
 164         nr_rsv = fdt_num_mem_rsv(fdt);
 165
 166         /* Look for an existing entry and add it to the efi mem map. */
 167         for (i = 0; i < nr_rsv; i++) {
 168                 if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
 169                         continue;
 170
 171                 /* Convert from sandbox address space. */
 172                 addr = (uintptr_t)map_sysmem(addr, 0);
 173
 174                 pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
 175                 addr &= ~EFI_PAGE_MASK;
 176                 if (!efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
 177                                         false))
 178                         printf("FDT memrsv map %d: Failed to add to map\n", i);
 179         }
 180 }
 181
 182 static efi_status_t efi_install_fdt(ulong fdt_addr)
 183 {
 184         bootm_headers_t img = { 0 };
 185         efi_status_t ret;
 186         void *fdt;
 187
 188         fdt = map_sysmem(fdt_addr, 0);
 189         if (fdt_check_header(fdt)) {
 190                 printf("ERROR: invalid device tree\n");
 191                 return EFI_INVALID_PARAMETER;
 192         }
 193
 194         /* Create memory reservation as indicated by the device tree */
 195         efi_carve_out_dt_rsv(fdt);
 196
 197         /* Prepare fdt for payload */
 198         ret = copy_fdt(&fdt);
 199         if (ret)
 200                 return ret;
 201
 202         if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 203                 printf("ERROR: failed to process device tree\n");
 204                 return EFI_LOAD_ERROR;
 205         }
 206
 207         /* Link to it in the efi tables */
 208         ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
 209         if (ret != EFI_SUCCESS)
 210                 return EFI_OUT_OF_RESOURCES;
 211
 212         return ret;
 213 }
 214
 215 static efi_status_t bootefi_run_prepare(const char *load_options_path,
 216                 struct efi_device_path *device_path,
 217                 struct efi_device_path *image_path,
 218                 struct efi_loaded_image_obj **image_objp,
 219                 struct efi_loaded_image **loaded_image_infop)
 220 {
 221         efi_status_t ret;
 222
 223         ret = efi_setup_loaded_image(device_path, image_path, image_objp,
 224                                      loaded_image_infop);
 225         if (ret != EFI_SUCCESS)
 226                 return ret;
 227
 228         /* Transfer environment variable as load options */
 229         set_load_options(*loaded_image_infop, load_options_path);
 230
 231         return 0;
 232 }
 233
 234 /**
 235  * bootefi_run_finish() - finish up after running an EFI test
 236  *
 237  * @loaded_image_info: Pointer to a struct which holds the loaded image info
 238  * @image_objj: Pointer to a struct which holds the loaded image object
 239  */
 240 static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
 241                                struct efi_loaded_image *loaded_image_info)
 242 {
 243         efi_restore_gd();
 244         free(loaded_image_info->load_options);
 245         efi_delete_handle(&image_obj->header);
 246 }
 247
 248 /**
 249  * do_bootefi_exec() - execute EFI binary
 250  *
 251  * @efi:                address of the binary
 252  * @device_path:        path of the device from which the binary was loaded
 253  * @image_path:         device path of the binary
 254  * Return:              status code
 255  *
 256  * Load the EFI binary into a newly assigned memory unwinding the relocation
 257  * information, install the loaded image protocol, and call the binary.
 258  */
 259 static efi_status_t do_bootefi_exec(void *efi,
 260                                     struct efi_device_path *device_path,
 261                                     struct efi_device_path *image_path)
 262 {
 263         efi_handle_t mem_handle = NULL;
 264         struct efi_device_path *memdp = NULL;
 265         efi_status_t ret;
 266         struct efi_loaded_image_obj *image_obj = NULL;
 267         struct efi_loaded_image *loaded_image_info = NULL;
 268
 269         EFIAPI efi_status_t (*entry)(efi_handle_t image_handle,
 270                                      struct efi_system_table *st);
 271
 272         /*
 273          * Special case for efi payload not loaded from disk, such as
 274          * 'bootefi hello' or for example payload loaded directly into
 275          * memory via JTAG, etc:
 276          */
 277         if (!device_path && !image_path) {
 278                 printf("WARNING: using memory device/image path, this may confuse some payloads!\n");
 279                 /* actual addresses filled in after efi_load_pe() */
 280                 memdp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 281                 device_path = image_path = memdp;
 282                 /*
 283                  * Grub expects that the device path of the loaded image is
 284                  * installed on a handle.
 285                  */
 286                 ret = efi_create_handle(&mem_handle);
 287                 if (ret != EFI_SUCCESS)
 288                         return ret; /* TODO: leaks device_path */
 289                 ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
 290                                        device_path);
 291                 if (ret != EFI_SUCCESS)
 292                         goto err_add_protocol;
 293         } else {
 294                 assert(device_path && image_path);
 295         }
 296
 297         ret = bootefi_run_prepare("bootargs", device_path, image_path,
 298                                   &image_obj, &loaded_image_info);
 299         if (ret)
 300                 goto err_prepare;
 301
 302         /* Load the EFI payload */
 303         entry = efi_load_pe(image_obj, efi, loaded_image_info);
 304         if (!entry) {
 305                 ret = EFI_LOAD_ERROR;
 306                 goto err_prepare;
 307         }
 308
 309         if (memdp) {
 310                 struct efi_device_path_memory *mdp = (void *)memdp;
 311                 mdp->memory_type = loaded_image_info->image_code_type;
 312                 mdp->start_address = (uintptr_t)loaded_image_info->image_base;
 313                 mdp->end_address = mdp->start_address +
 314                                 loaded_image_info->image_size;
 315         }
 316
 317         /* we don't support much: */
 318         env_set("efi_8be4df61-93ca-11d2-aa0d-00e098032b8c_OsIndicationsSupported",
 319                 "{ro,boot}(blob)0000000000000000");
 320
 321         /* Call our payload! */
 322         debug("%s: Jumping to 0x%p\n", __func__, entry);
 323
 324         if (setjmp(&image_obj->exit_jmp)) {
 325                 ret = image_obj->exit_status;
 326                 goto err_prepare;
 327         }
 328
 329         ret = efi_do_enter(&image_obj->header, &systab, entry);
 330
 331 err_prepare:
 332         /* image has returned, loaded-image obj goes *poof*: */
 333         bootefi_run_finish(image_obj, loaded_image_info);
 334
 335 err_add_protocol:
 336         if (mem_handle)
 337                 efi_delete_handle(mem_handle);
 338
 339         return ret;
 340 }
 341
 342 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 343 /**
 344  * bootefi_test_prepare() - prepare to run an EFI test
 345  *
 346  * This sets things up so we can call EFI functions. This involves preparing
 347  * the 'gd' pointer and setting up the load ed image data structures.
 348  *
 349  * @image_objp: loaded_image_infop: Pointer to a struct which will hold the
 350  *    loaded image object. This struct will be inited by this function before
 351  *    use.
 352  * @loaded_image_infop: Pointer to a struct which will hold the loaded image
 353  *    info. This struct will be inited by this function before use.
 354  * @path: File path to the test being run (often just the test name with a
 355  *    backslash before it
 356  * @test_func: Address of the test function that is being run
 357  * @load_options_path: U-Boot environment variable to use as load options
 358  * @return 0 if OK, -ve on error
 359  */
 360 static efi_status_t bootefi_test_prepare
 361                 (struct efi_loaded_image_obj **image_objp,
 362                 struct efi_loaded_image **loaded_image_infop, const char *path,
 363                 ulong test_func, const char *load_options_path)
 364 {
 365         /* Construct a dummy device path */
 366         bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
 367                                               (uintptr_t)test_func,
 368                                               (uintptr_t)test_func);
 369         if (!bootefi_device_path)
 370                 return EFI_OUT_OF_RESOURCES;
 371         bootefi_image_path = efi_dp_from_file(NULL, 0, path);
 372         if (!bootefi_image_path)
 373                 return EFI_OUT_OF_RESOURCES;
 374
 375         return bootefi_run_prepare(load_options_path, bootefi_device_path,
 376                                    bootefi_image_path, image_objp,
 377                                    loaded_image_infop);
 378 }
 379
 380 #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
 381
 382 static int do_bootefi_bootmgr_exec(void)
 383 {
 384         struct efi_device_path *device_path, *file_path;
 385         void *addr;
 386         efi_status_t r;
 387
 388         addr = efi_bootmgr_load(&device_path, &file_path);
 389         if (!addr)
 390                 return 1;
 391
 392         printf("## Starting EFI application at %p ...\n", addr);
 393         r = do_bootefi_exec(addr, device_path, file_path);
 394         printf("## Application terminated, r = %lu\n",
 395                r & ~EFI_ERROR_MASK);
 396
 397         if (r != EFI_SUCCESS)
 398                 return 1;
 399
 400         return 0;
 401 }
 402
 403 /* Interpreter command to boot an arbitrary EFI image from memory */
 404 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 405 {
 406         unsigned long addr;
 407         char *saddr;
 408         efi_status_t r;
 409         unsigned long fdt_addr;
 410
 411         /* Allow unaligned memory access */
 412         allow_unaligned();
 413
 414         switch_to_non_secure_mode();
 415
 416         /* Initialize EFI drivers */
 417         r = efi_init_obj_list();
 418         if (r != EFI_SUCCESS) {
 419                 printf("Error: Cannot set up EFI drivers, r = %lu\n",
 420                        r & ~EFI_ERROR_MASK);
 421                 return CMD_RET_FAILURE;
 422         }
 423
 424         if (argc < 2)
 425                 return CMD_RET_USAGE;
 426
 427         if (argc > 2) {
 428                 fdt_addr = simple_strtoul(argv[2], NULL, 16);
 429                 if (!fdt_addr && *argv[2] != '0')
 430                         return CMD_RET_USAGE;
 431                 /* Install device tree */
 432                 r = efi_install_fdt(fdt_addr);
 433                 if (r != EFI_SUCCESS) {
 434                         printf("ERROR: failed to install device tree\n");
 435                         return CMD_RET_FAILURE;
 436                 }
 437         } else {
 438                 /* Remove device tree. EFI_NOT_FOUND can be ignored here */
 439                 efi_install_configuration_table(&efi_guid_fdt, NULL);
 440                 printf("WARNING: booting without device tree\n");
 441         }
 442 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 443         if (!strcmp(argv[1], "hello")) {
 444                 ulong size = __efi_helloworld_end - __efi_helloworld_begin;
 445
 446                 saddr = env_get("loadaddr");
 447                 if (saddr)
 448                         addr = simple_strtoul(saddr, NULL, 16);
 449                 else
 450                         addr = CONFIG_SYS_LOAD_ADDR;
 451                 memcpy(map_sysmem(addr, size), __efi_helloworld_begin, size);
 452         } else
 453 #endif
 454 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 455         if (!strcmp(argv[1], "selftest")) {
 456                 struct efi_loaded_image_obj *image_obj;
 457                 struct efi_loaded_image *loaded_image_info;
 458
 459                 if (bootefi_test_prepare(&image_obj, &loaded_image_info,
 460                                          "\\selftest", (uintptr_t)&efi_selftest,
 461                                          "efi_selftest"))
 462                         return CMD_RET_FAILURE;
 463
 464                 /* Execute the test */
 465                 r = efi_selftest(&image_obj->header, &systab);
 466                 bootefi_run_finish(image_obj, loaded_image_info);
 467                 return r != EFI_SUCCESS;
 468         } else
 469 #endif
 470         if (!strcmp(argv[1], "bootmgr")) {
 471                 return do_bootefi_bootmgr_exec();
 472         } else {
 473                 saddr = argv[1];
 474
 475                 addr = simple_strtoul(saddr, NULL, 16);
 476                 /* Check that a numeric value was passed */
 477                 if (!addr && *saddr != '0')
 478                         return CMD_RET_USAGE;
 479
 480         }
 481
 482         printf("## Starting EFI application at %08lx ...\n", addr);
 483         r = do_bootefi_exec(map_sysmem(addr, 0), bootefi_device_path,
 484                             bootefi_image_path);
 485         printf("## Application terminated, r = %lu\n",
 486                r & ~EFI_ERROR_MASK);
 487
 488         if (r != EFI_SUCCESS)
 489                 return 1;
 490         else
 491                 return 0;
 492 }
 493
 494 #ifdef CONFIG_SYS_LONGHELP
 495 static char bootefi_help_text[] =
 496         "<image address> [fdt address]\n"
 497         "  - boot EFI payload stored at address <image address>.\n"
 498         "    If specified, the device tree located at <fdt address> gets\n"
 499         "    exposed as EFI configuration table.\n"
 500 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 501         "bootefi hello\n"
 502         "  - boot a sample Hello World application stored within U-Boot\n"
 503 #endif
 504 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 505         "bootefi selftest [fdt address]\n"
 506         "  - boot an EFI selftest application stored within U-Boot\n"
 507         "    Use environment variable efi_selftest to select a single test.\n"
 508         "    Use 'setenv efi_selftest list' to enumerate all tests.\n"
 509 #endif
 510         "bootefi bootmgr [fdt addr]\n"
 511         "  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
 512         "\n"
 513         "    If specified, the device tree located at <fdt address> gets\n"
 514         "    exposed as EFI configuration table.\n";
 515 #endif
 516
 517 U_BOOT_CMD(
 518         bootefi, 3, 0, do_bootefi,
 519         "Boots an EFI payload from memory",
 520         bootefi_help_text
 521 );
 522
 523 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 524 {
 525         struct efi_device_path *device, *image;
 526         efi_status_t ret;
 527
 528         /* efi_set_bootdev is typically called repeatedly, recover memory */
 529         efi_free_pool(bootefi_device_path);
 530         efi_free_pool(bootefi_image_path);
 531
 532         ret = efi_dp_from_name(dev, devnr, path, &device, &image);
 533         if (ret == EFI_SUCCESS) {
 534                 bootefi_device_path = device;
 535                 bootefi_image_path = image;
 536         } else {
 537                 bootefi_device_path = NULL;
 538                 bootefi_image_path = NULL;
 539         }
 540 }