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_BOOT_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_BOOT_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 /*
 137  * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
 138  *
 139  * The mem_rsv entries of the FDT are added to the memory map. Any failures are
 140  * ignored because this is not critical and we would rather continue to try to
 141  * boot.
 142  *
 143  * @fdt: Pointer to device tree
 144  */
 145 static void efi_carve_out_dt_rsv(void *fdt)
 146 {
 147         int nr_rsv, i;
 148         uint64_t addr, size, pages;
 149
 150         nr_rsv = fdt_num_mem_rsv(fdt);
 151
 152         /* Look for an existing entry and add it to the efi mem map. */
 153         for (i = 0; i < nr_rsv; i++) {
 154                 if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
 155                         continue;
 156
 157                 /* Convert from sandbox address space. */
 158                 addr = (uintptr_t)map_sysmem(addr, 0);
 159
 160                 pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
 161                 addr &= ~EFI_PAGE_MASK;
 162                 if (!efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
 163                                         false))
 164                         printf("FDT memrsv map %d: Failed to add to map\n", i);
 165         }
 166 }
 167
 168 static efi_status_t efi_install_fdt(ulong fdt_addr)
 169 {
 170         bootm_headers_t img = { 0 };
 171         efi_status_t ret;
 172         void *fdt;
 173
 174         fdt = map_sysmem(fdt_addr, 0);
 175         if (fdt_check_header(fdt)) {
 176                 printf("ERROR: invalid device tree\n");
 177                 return EFI_INVALID_PARAMETER;
 178         }
 179
 180         /* Create memory reservation as indicated by the device tree */
 181         efi_carve_out_dt_rsv(fdt);
 182
 183         /* Prepare fdt for payload */
 184         ret = copy_fdt(&fdt);
 185         if (ret)
 186                 return ret;
 187
 188         if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 189                 printf("ERROR: failed to process device tree\n");
 190                 return EFI_LOAD_ERROR;
 191         }
 192
 193         /* Link to it in the efi tables */
 194         ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
 195         if (ret != EFI_SUCCESS)
 196                 return EFI_OUT_OF_RESOURCES;
 197
 198         return ret;
 199 }
 200
 201 static efi_status_t bootefi_run_prepare(const char *load_options_path,
 202                 struct efi_device_path *device_path,
 203                 struct efi_device_path *image_path,
 204                 struct efi_loaded_image_obj **image_objp,
 205                 struct efi_loaded_image **loaded_image_infop)
 206 {
 207         efi_status_t ret;
 208
 209         ret = efi_setup_loaded_image(device_path, image_path, image_objp,
 210                                      loaded_image_infop);
 211         if (ret != EFI_SUCCESS)
 212                 return ret;
 213
 214         /* Transfer environment variable as load options */
 215         set_load_options(*loaded_image_infop, load_options_path);
 216
 217         return 0;
 218 }
 219
 220 /**
 221  * bootefi_run_finish() - finish up after running an EFI test
 222  *
 223  * @loaded_image_info: Pointer to a struct which holds the loaded image info
 224  * @image_objj: Pointer to a struct which holds the loaded image object
 225  */
 226 static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
 227                                struct efi_loaded_image *loaded_image_info)
 228 {
 229         efi_restore_gd();
 230         free(loaded_image_info->load_options);
 231         efi_delete_handle(&image_obj->header);
 232 }
 233
 234 /**
 235  * do_bootefi_exec() - execute EFI binary
 236  *
 237  * @efi:                address of the binary
 238  * @device_path:        path of the device from which the binary was loaded
 239  * @image_path:         device path of the binary
 240  * Return:              status code
 241  *
 242  * Load the EFI binary into a newly assigned memory unwinding the relocation
 243  * information, install the loaded image protocol, and call the binary.
 244  */
 245 static efi_status_t do_bootefi_exec(void *efi,
 246                                     struct efi_device_path *device_path,
 247                                     struct efi_device_path *image_path)
 248 {
 249         efi_handle_t mem_handle = NULL;
 250         struct efi_device_path *memdp = NULL;
 251         efi_status_t ret;
 252         struct efi_loaded_image_obj *image_obj = NULL;
 253         struct efi_loaded_image *loaded_image_info = NULL;
 254
 255         /*
 256          * Special case for efi payload not loaded from disk, such as
 257          * 'bootefi hello' or for example payload loaded directly into
 258          * memory via JTAG, etc:
 259          */
 260         if (!device_path && !image_path) {
 261                 printf("WARNING: using memory device/image path, this may confuse some payloads!\n");
 262                 /* actual addresses filled in after efi_load_pe() */
 263                 memdp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 264                 device_path = image_path = memdp;
 265                 /*
 266                  * Grub expects that the device path of the loaded image is
 267                  * installed on a handle.
 268                  */
 269                 ret = efi_create_handle(&mem_handle);
 270                 if (ret != EFI_SUCCESS)
 271                         return ret; /* TODO: leaks device_path */
 272                 ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
 273                                        device_path);
 274                 if (ret != EFI_SUCCESS)
 275                         goto err_add_protocol;
 276         } else {
 277                 assert(device_path && image_path);
 278         }
 279
 280         ret = bootefi_run_prepare("bootargs", device_path, image_path,
 281                                   &image_obj, &loaded_image_info);
 282         if (ret)
 283                 goto err_prepare;
 284
 285         /* Load the EFI payload */
 286         ret = efi_load_pe(image_obj, efi, loaded_image_info);
 287         if (ret != EFI_SUCCESS)
 288                 goto err_prepare;
 289
 290         if (memdp) {
 291                 struct efi_device_path_memory *mdp = (void *)memdp;
 292                 mdp->memory_type = loaded_image_info->image_code_type;
 293                 mdp->start_address = (uintptr_t)loaded_image_info->image_base;
 294                 mdp->end_address = mdp->start_address +
 295                                 loaded_image_info->image_size;
 296         }
 297
 298         /* we don't support much: */
 299         env_set("efi_8be4df61-93ca-11d2-aa0d-00e098032b8c_OsIndicationsSupported",
 300                 "{ro,boot}(blob)0000000000000000");
 301
 302         /* Call our payload! */
 303         debug("%s: Jumping to 0x%p\n", __func__, image_obj->entry);
 304         ret = EFI_CALL(efi_start_image(&image_obj->header, NULL, NULL));
 305
 306 err_prepare:
 307         /* image has returned, loaded-image obj goes *poof*: */
 308         bootefi_run_finish(image_obj, loaded_image_info);
 309
 310 err_add_protocol:
 311         if (mem_handle)
 312                 efi_delete_handle(mem_handle);
 313
 314         return ret;
 315 }
 316
 317 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 318 /**
 319  * bootefi_test_prepare() - prepare to run an EFI test
 320  *
 321  * Prepare to run a test as if it were provided by a loaded image.
 322  *
 323  * @image_objp:         pointer to be set to the loaded image handle
 324  * @loaded_image_infop: pointer to be set to the loaded image protocol
 325  * @path:               dummy file path used to construct the device path
 326  *                      set in the loaded image protocol
 327  * @load_options_path:  name of a U-Boot environment variable. Its value is
 328  *                      set as load options in the loaded image protocol.
 329  * Return:              status code
 330  */
 331 static efi_status_t bootefi_test_prepare
 332                 (struct efi_loaded_image_obj **image_objp,
 333                  struct efi_loaded_image **loaded_image_infop, const char *path,
 334                  const char *load_options_path)
 335 {
 336         efi_status_t ret;
 337
 338         /* Construct a dummy device path */
 339         bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 340         if (!bootefi_device_path)
 341                 return EFI_OUT_OF_RESOURCES;
 342
 343         bootefi_image_path = efi_dp_from_file(NULL, 0, path);
 344         if (!bootefi_image_path) {
 345                 ret = EFI_OUT_OF_RESOURCES;
 346                 goto failure;
 347         }
 348
 349         ret = bootefi_run_prepare(load_options_path, bootefi_device_path,
 350                                   bootefi_image_path, image_objp,
 351                                   loaded_image_infop);
 352         if (ret == EFI_SUCCESS)
 353                 return ret;
 354
 355         efi_free_pool(bootefi_image_path);
 356         bootefi_image_path = NULL;
 357 failure:
 358         efi_free_pool(bootefi_device_path);
 359         bootefi_device_path = NULL;
 360         return ret;
 361 }
 362
 363 #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
 364
 365 static int do_bootefi_bootmgr_exec(void)
 366 {
 367         struct efi_device_path *device_path, *file_path;
 368         void *addr;
 369         efi_status_t r;
 370
 371         addr = efi_bootmgr_load(&device_path, &file_path);
 372         if (!addr)
 373                 return 1;
 374
 375         printf("## Starting EFI application at %p ...\n", addr);
 376         r = do_bootefi_exec(addr, device_path, file_path);
 377         printf("## Application terminated, r = %lu\n",
 378                r & ~EFI_ERROR_MASK);
 379
 380         if (r != EFI_SUCCESS)
 381                 return 1;
 382
 383         return 0;
 384 }
 385
 386 /* Interpreter command to boot an arbitrary EFI image from memory */
 387 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 388 {
 389         unsigned long addr;
 390         char *saddr;
 391         efi_status_t r;
 392         unsigned long fdt_addr;
 393
 394         /* Allow unaligned memory access */
 395         allow_unaligned();
 396
 397         switch_to_non_secure_mode();
 398
 399         /* Initialize EFI drivers */
 400         r = efi_init_obj_list();
 401         if (r != EFI_SUCCESS) {
 402                 printf("Error: Cannot set up EFI drivers, r = %lu\n",
 403                        r & ~EFI_ERROR_MASK);
 404                 return CMD_RET_FAILURE;
 405         }
 406
 407         if (argc < 2)
 408                 return CMD_RET_USAGE;
 409
 410         if (argc > 2) {
 411                 fdt_addr = simple_strtoul(argv[2], NULL, 16);
 412                 if (!fdt_addr && *argv[2] != '0')
 413                         return CMD_RET_USAGE;
 414                 /* Install device tree */
 415                 r = efi_install_fdt(fdt_addr);
 416                 if (r != EFI_SUCCESS) {
 417                         printf("ERROR: failed to install device tree\n");
 418                         return CMD_RET_FAILURE;
 419                 }
 420         } else {
 421                 /* Remove device tree. EFI_NOT_FOUND can be ignored here */
 422                 efi_install_configuration_table(&efi_guid_fdt, NULL);
 423                 printf("WARNING: booting without device tree\n");
 424         }
 425 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 426         if (!strcmp(argv[1], "hello")) {
 427                 ulong size = __efi_helloworld_end - __efi_helloworld_begin;
 428
 429                 saddr = env_get("loadaddr");
 430                 if (saddr)
 431                         addr = simple_strtoul(saddr, NULL, 16);
 432                 else
 433                         addr = CONFIG_SYS_LOAD_ADDR;
 434                 memcpy(map_sysmem(addr, size), __efi_helloworld_begin, size);
 435         } else
 436 #endif
 437 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 438         if (!strcmp(argv[1], "selftest")) {
 439                 struct efi_loaded_image_obj *image_obj;
 440                 struct efi_loaded_image *loaded_image_info;
 441
 442                 r = bootefi_test_prepare(&image_obj, &loaded_image_info,
 443                                          "\\selftest", "efi_selftest");
 444                 if (r != EFI_SUCCESS)
 445                         return CMD_RET_FAILURE;
 446
 447                 /* Execute the test */
 448                 r = EFI_CALL(efi_selftest(&image_obj->header, &systab));
 449                 bootefi_run_finish(image_obj, loaded_image_info);
 450                 return r != EFI_SUCCESS;
 451         } else
 452 #endif
 453         if (!strcmp(argv[1], "bootmgr")) {
 454                 return do_bootefi_bootmgr_exec();
 455         } else {
 456                 saddr = argv[1];
 457
 458                 addr = simple_strtoul(saddr, NULL, 16);
 459                 /* Check that a numeric value was passed */
 460                 if (!addr && *saddr != '0')
 461                         return CMD_RET_USAGE;
 462
 463         }
 464
 465         printf("## Starting EFI application at %08lx ...\n", addr);
 466         r = do_bootefi_exec(map_sysmem(addr, 0), bootefi_device_path,
 467                             bootefi_image_path);
 468         printf("## Application terminated, r = %lu\n",
 469                r & ~EFI_ERROR_MASK);
 470
 471         if (r != EFI_SUCCESS)
 472                 return 1;
 473         else
 474                 return 0;
 475 }
 476
 477 #ifdef CONFIG_SYS_LONGHELP
 478 static char bootefi_help_text[] =
 479         "<image address> [fdt address]\n"
 480         "  - boot EFI payload stored at address <image address>.\n"
 481         "    If specified, the device tree located at <fdt address> gets\n"
 482         "    exposed as EFI configuration table.\n"
 483 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 484         "bootefi hello\n"
 485         "  - boot a sample Hello World application stored within U-Boot\n"
 486 #endif
 487 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 488         "bootefi selftest [fdt address]\n"
 489         "  - boot an EFI selftest application stored within U-Boot\n"
 490         "    Use environment variable efi_selftest to select a single test.\n"
 491         "    Use 'setenv efi_selftest list' to enumerate all tests.\n"
 492 #endif
 493         "bootefi bootmgr [fdt addr]\n"
 494         "  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
 495         "\n"
 496         "    If specified, the device tree located at <fdt address> gets\n"
 497         "    exposed as EFI configuration table.\n";
 498 #endif
 499
 500 U_BOOT_CMD(
 501         bootefi, 3, 0, do_bootefi,
 502         "Boots an EFI payload from memory",
 503         bootefi_help_text
 504 );
 505
 506 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 507 {
 508         struct efi_device_path *device, *image;
 509         efi_status_t ret;
 510
 511         /* efi_set_bootdev is typically called repeatedly, recover memory */
 512         efi_free_pool(bootefi_device_path);
 513         efi_free_pool(bootefi_image_path);
 514
 515         ret = efi_dp_from_name(dev, devnr, path, &device, &image);
 516         if (ret == EFI_SUCCESS) {
 517                 bootefi_device_path = device;
 518                 bootefi_image_path = image;
 519         } else {
 520                 bootefi_device_path = NULL;
 521                 bootefi_image_path = NULL;
 522         }
 523 }