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 <charset.h>
   9 #include <common.h>
  10 #include <command.h>
  11 #include <dm.h>
  12 #include <efi_loader.h>
  13 #include <efi_selftest.h>
  14 #include <errno.h>
  15 #include <linux/libfdt.h>
  16 #include <linux/libfdt_env.h>
  17 #include <mapmem.h>
  18 #include <memalign.h>
  19 #include <asm/global_data.h>
  20 #include <asm-generic/sections.h>
  21 #include <asm-generic/unaligned.h>
  22 #include <linux/linkage.h>
  23
  24 #ifdef CONFIG_ARMV7_NONSEC
  25 #include <asm/armv7.h>
  26 #include <asm/secure.h>
  27 #endif
  28
  29 DECLARE_GLOBAL_DATA_PTR;
  30
  31 static struct efi_device_path *bootefi_image_path;
  32 static struct efi_device_path *bootefi_device_path;
  33
  34 /*
  35  * Allow unaligned memory access.
  36  *
  37  * This routine is overridden by architectures providing this feature.
  38  */
  39 void __weak allow_unaligned(void)
  40 {
  41 }
  42
  43 /*
  44  * Set the load options of an image from an environment variable.
  45  *
  46  * @loaded_image_info:  the image
  47  * @env_var:            name of the environment variable
  48  */
  49 static void set_load_options(struct efi_loaded_image *loaded_image_info,
  50                              const char *env_var)
  51 {
  52         size_t size;
  53         const char *env = env_get(env_var);
  54         u16 *pos;
  55
  56         loaded_image_info->load_options = NULL;
  57         loaded_image_info->load_options_size = 0;
  58         if (!env)
  59                 return;
  60         size = utf8_utf16_strlen(env) + 1;
  61         loaded_image_info->load_options = calloc(size, sizeof(u16));
  62         if (!loaded_image_info->load_options) {
  63                 printf("ERROR: Out of memory\n");
  64                 return;
  65         }
  66         pos = loaded_image_info->load_options;
  67         utf8_utf16_strcpy(&pos, env);
  68         loaded_image_info->load_options_size = size * 2;
  69 }
  70
  71 /**
  72  * copy_fdt() - Copy the device tree to a new location available to EFI
  73  *
  74  * The FDT is copied to a suitable location within the EFI memory map.
  75  * Additional 12 KiB are added to the space in case the device tree needs to be
  76  * expanded later with fdt_open_into().
  77  *
  78  * @fdtp:       On entry a pointer to the flattened device tree.
  79  *              On exit a pointer to the copy of the flattened device tree.
  80  *              FDT start
  81  * Return:      status code
  82  */
  83 static efi_status_t copy_fdt(void **fdtp)
  84 {
  85         unsigned long fdt_ram_start = -1L, fdt_pages;
  86         efi_status_t ret = 0;
  87         void *fdt, *new_fdt;
  88         u64 new_fdt_addr;
  89         uint fdt_size;
  90         int i;
  91
  92         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
  93                 u64 ram_start = gd->bd->bi_dram[i].start;
  94                 u64 ram_size = gd->bd->bi_dram[i].size;
  95
  96                 if (!ram_size)
  97                         continue;
  98
  99                 if (ram_start < fdt_ram_start)
 100                         fdt_ram_start = ram_start;
 101         }
 102
 103         /*
 104          * Give us at least 12 KiB of breathing room in case the device tree
 105          * needs to be expanded later.
 106          */
 107         fdt = *fdtp;
 108         fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
 109         fdt_size = fdt_pages << EFI_PAGE_SHIFT;
 110
 111         /*
 112          * Safe fdt location is at 127 MiB.
 113          * On the sandbox convert from the sandbox address space.
 114          */
 115         new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
 116                                              fdt_size, 0);
 117         ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 118                                  EFI_RUNTIME_SERVICES_DATA, fdt_pages,
 119                                  &new_fdt_addr);
 120         if (ret != EFI_SUCCESS) {
 121                 /* If we can't put it there, put it somewhere */
 122                 new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
 123                 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 124                                          EFI_RUNTIME_SERVICES_DATA, fdt_pages,
 125                                          &new_fdt_addr);
 126                 if (ret != EFI_SUCCESS) {
 127                         printf("ERROR: Failed to reserve space for FDT\n");
 128                         goto done;
 129                 }
 130         }
 131         new_fdt = (void *)(uintptr_t)new_fdt_addr;
 132         memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 133         fdt_set_totalsize(new_fdt, fdt_size);
 134
 135         *fdtp = (void *)(uintptr_t)new_fdt_addr;
 136 done:
 137         return ret;
 138 }
 139
 140 static efi_status_t efi_do_enter(
 141                         efi_handle_t image_handle, struct efi_system_table *st,
 142                         EFIAPI efi_status_t (*entry)(
 143                                 efi_handle_t image_handle,
 144                                 struct efi_system_table *st))
 145 {
 146         efi_status_t ret = EFI_LOAD_ERROR;
 147
 148         if (entry)
 149                 ret = entry(image_handle, st);
 150         st->boottime->exit(image_handle, ret, 0, NULL);
 151         return ret;
 152 }
 153
 154 #ifdef CONFIG_ARM64
 155 static efi_status_t efi_run_in_el2(EFIAPI efi_status_t (*entry)(
 156                         efi_handle_t image_handle, struct efi_system_table *st),
 157                         efi_handle_t image_handle, struct efi_system_table *st)
 158 {
 159         /* Enable caches again */
 160         dcache_enable();
 161
 162         return efi_do_enter(image_handle, st, entry);
 163 }
 164 #endif
 165
 166 #ifdef CONFIG_ARMV7_NONSEC
 167 static bool is_nonsec;
 168
 169 static efi_status_t efi_run_in_hyp(EFIAPI efi_status_t (*entry)(
 170                         efi_handle_t image_handle, struct efi_system_table *st),
 171                         efi_handle_t image_handle, struct efi_system_table *st)
 172 {
 173         /* Enable caches again */
 174         dcache_enable();
 175
 176         is_nonsec = true;
 177
 178         return efi_do_enter(image_handle, st, entry);
 179 }
 180 #endif
 181
 182 /*
 183  * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
 184  *
 185  * The mem_rsv entries of the FDT are added to the memory map. Any failures are
 186  * ignored because this is not critical and we would rather continue to try to
 187  * boot.
 188  *
 189  * @fdt: Pointer to device tree
 190  */
 191 static void efi_carve_out_dt_rsv(void *fdt)
 192 {
 193         int nr_rsv, i;
 194         uint64_t addr, size, pages;
 195
 196         nr_rsv = fdt_num_mem_rsv(fdt);
 197
 198         /* Look for an existing entry and add it to the efi mem map. */
 199         for (i = 0; i < nr_rsv; i++) {
 200                 if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
 201                         continue;
 202
 203                 /* Convert from sandbox address space. */
 204                 addr = (uintptr_t)map_sysmem(addr, 0);
 205
 206                 pages = efi_size_in_pages(size + (addr & EFI_PAGE_MASK));
 207                 addr &= ~EFI_PAGE_MASK;
 208                 if (!efi_add_memory_map(addr, pages, EFI_RESERVED_MEMORY_TYPE,
 209                                         false))
 210                         printf("FDT memrsv map %d: Failed to add to map\n", i);
 211         }
 212 }
 213
 214 static efi_status_t efi_install_fdt(ulong fdt_addr)
 215 {
 216         bootm_headers_t img = { 0 };
 217         efi_status_t ret;
 218         void *fdt;
 219
 220         fdt = map_sysmem(fdt_addr, 0);
 221         if (fdt_check_header(fdt)) {
 222                 printf("ERROR: invalid device tree\n");
 223                 return EFI_INVALID_PARAMETER;
 224         }
 225
 226         /* Create memory reservation as indicated by the device tree */
 227         efi_carve_out_dt_rsv(fdt);
 228
 229         /* Prepare fdt for payload */
 230         ret = copy_fdt(&fdt);
 231         if (ret)
 232                 return ret;
 233
 234         if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 235                 printf("ERROR: failed to process device tree\n");
 236                 return EFI_LOAD_ERROR;
 237         }
 238
 239         /* Link to it in the efi tables */
 240         ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
 241         if (ret != EFI_SUCCESS)
 242                 return EFI_OUT_OF_RESOURCES;
 243
 244         return ret;
 245 }
 246
 247 static efi_status_t bootefi_run_prepare(const char *load_options_path,
 248                 struct efi_device_path *device_path,
 249                 struct efi_device_path *image_path,
 250                 struct efi_loaded_image_obj **image_objp,
 251                 struct efi_loaded_image **loaded_image_infop)
 252 {
 253         efi_status_t ret;
 254
 255         ret = efi_setup_loaded_image(device_path, image_path, image_objp,
 256                                      loaded_image_infop);
 257         if (ret != EFI_SUCCESS)
 258                 return ret;
 259
 260         /* Transfer environment variable as load options */
 261         set_load_options(*loaded_image_infop, load_options_path);
 262
 263         return 0;
 264 }
 265
 266 /**
 267  * bootefi_run_finish() - finish up after running an EFI test
 268  *
 269  * @loaded_image_info: Pointer to a struct which holds the loaded image info
 270  * @image_objj: Pointer to a struct which holds the loaded image object
 271  */
 272 static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
 273                                struct efi_loaded_image *loaded_image_info)
 274 {
 275         efi_restore_gd();
 276         free(loaded_image_info->load_options);
 277         efi_delete_handle(&image_obj->header);
 278 }
 279
 280 /**
 281  * do_bootefi_exec() - execute EFI binary
 282  *
 283  * @efi:                address of the binary
 284  * @device_path:        path of the device from which the binary was loaded
 285  * @image_path:         device path of the binary
 286  * Return:              status code
 287  *
 288  * Load the EFI binary into a newly assigned memory unwinding the relocation
 289  * information, install the loaded image protocol, and call the binary.
 290  */
 291 static efi_status_t do_bootefi_exec(void *efi,
 292                                     struct efi_device_path *device_path,
 293                                     struct efi_device_path *image_path)
 294 {
 295         efi_handle_t mem_handle = NULL;
 296         struct efi_device_path *memdp = NULL;
 297         efi_status_t ret;
 298         struct efi_loaded_image_obj *image_obj = NULL;
 299         struct efi_loaded_image *loaded_image_info = NULL;
 300
 301         EFIAPI efi_status_t (*entry)(efi_handle_t image_handle,
 302                                      struct efi_system_table *st);
 303
 304         /*
 305          * Special case for efi payload not loaded from disk, such as
 306          * 'bootefi hello' or for example payload loaded directly into
 307          * memory via JTAG, etc:
 308          */
 309         if (!device_path && !image_path) {
 310                 printf("WARNING: using memory device/image path, this may confuse some payloads!\n");
 311                 /* actual addresses filled in after efi_load_pe() */
 312                 memdp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 313                 device_path = image_path = memdp;
 314                 /*
 315                  * Grub expects that the device path of the loaded image is
 316                  * installed on a handle.
 317                  */
 318                 ret = efi_create_handle(&mem_handle);
 319                 if (ret != EFI_SUCCESS)
 320                         return ret; /* TODO: leaks device_path */
 321                 ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
 322                                        device_path);
 323                 if (ret != EFI_SUCCESS)
 324                         goto err_add_protocol;
 325         } else {
 326                 assert(device_path && image_path);
 327         }
 328
 329         ret = bootefi_run_prepare("bootargs", device_path, image_path,
 330                                   &image_obj, &loaded_image_info);
 331         if (ret)
 332                 goto err_prepare;
 333
 334         /* Load the EFI payload */
 335         entry = efi_load_pe(image_obj, efi, loaded_image_info);
 336         if (!entry) {
 337                 ret = EFI_LOAD_ERROR;
 338                 goto err_prepare;
 339         }
 340
 341         if (memdp) {
 342                 struct efi_device_path_memory *mdp = (void *)memdp;
 343                 mdp->memory_type = loaded_image_info->image_code_type;
 344                 mdp->start_address = (uintptr_t)loaded_image_info->image_base;
 345                 mdp->end_address = mdp->start_address +
 346                                 loaded_image_info->image_size;
 347         }
 348
 349         /* we don't support much: */
 350         env_set("efi_8be4df61-93ca-11d2-aa0d-00e098032b8c_OsIndicationsSupported",
 351                 "{ro,boot}(blob)0000000000000000");
 352
 353         /* Call our payload! */
 354         debug("%s: Jumping to 0x%p\n", __func__, entry);
 355
 356         if (setjmp(&image_obj->exit_jmp)) {
 357                 ret = image_obj->exit_status;
 358                 goto err_prepare;
 359         }
 360
 361 #ifdef CONFIG_ARM64
 362         /* On AArch64 we need to make sure we call our payload in < EL3 */
 363         if (current_el() == 3) {
 364                 smp_kick_all_cpus();
 365                 dcache_disable();       /* flush cache before switch to EL2 */
 366
 367                 /* Move into EL2 and keep running there */
 368                 armv8_switch_to_el2((ulong)entry,
 369                                     (ulong)&image_obj->header,
 370                                     (ulong)&systab, 0, (ulong)efi_run_in_el2,
 371                                     ES_TO_AARCH64);
 372
 373                 /* Should never reach here, efi exits with longjmp */
 374                 while (1) { }
 375         }
 376 #endif
 377
 378 #ifdef CONFIG_ARMV7_NONSEC
 379         if (armv7_boot_nonsec() && !is_nonsec) {
 380                 dcache_disable();       /* flush cache before switch to HYP */
 381
 382                 armv7_init_nonsec();
 383                 secure_ram_addr(_do_nonsec_entry)(
 384                                         efi_run_in_hyp,
 385                                         (uintptr_t)entry,
 386                                         (uintptr_t)&image_obj->header,
 387                                         (uintptr_t)&systab);
 388
 389                 /* Should never reach here, efi exits with longjmp */
 390                 while (1) { }
 391         }
 392 #endif
 393
 394         ret = efi_do_enter(&image_obj->header, &systab, entry);
 395
 396 err_prepare:
 397         /* image has returned, loaded-image obj goes *poof*: */
 398         bootefi_run_finish(image_obj, loaded_image_info);
 399
 400 err_add_protocol:
 401         if (mem_handle)
 402                 efi_delete_handle(mem_handle);
 403
 404         return ret;
 405 }
 406
 407 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 408 /**
 409  * bootefi_test_prepare() - prepare to run an EFI test
 410  *
 411  * This sets things up so we can call EFI functions. This involves preparing
 412  * the 'gd' pointer and setting up the load ed image data structures.
 413  *
 414  * @image_objp: loaded_image_infop: Pointer to a struct which will hold the
 415  *    loaded image object. This struct will be inited by this function before
 416  *    use.
 417  * @loaded_image_infop: Pointer to a struct which will hold the loaded image
 418  *    info. This struct will be inited by this function before use.
 419  * @path: File path to the test being run (often just the test name with a
 420  *    backslash before it
 421  * @test_func: Address of the test function that is being run
 422  * @load_options_path: U-Boot environment variable to use as load options
 423  * @return 0 if OK, -ve on error
 424  */
 425 static efi_status_t bootefi_test_prepare
 426                 (struct efi_loaded_image_obj **image_objp,
 427                 struct efi_loaded_image **loaded_image_infop, const char *path,
 428                 ulong test_func, const char *load_options_path)
 429 {
 430         /* Construct a dummy device path */
 431         bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
 432                                               (uintptr_t)test_func,
 433                                               (uintptr_t)test_func);
 434         if (!bootefi_device_path)
 435                 return EFI_OUT_OF_RESOURCES;
 436         bootefi_image_path = efi_dp_from_file(NULL, 0, path);
 437         if (!bootefi_image_path)
 438                 return EFI_OUT_OF_RESOURCES;
 439
 440         return bootefi_run_prepare(load_options_path, bootefi_device_path,
 441                                    bootefi_image_path, image_objp,
 442                                    loaded_image_infop);
 443 }
 444
 445 #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
 446
 447 static int do_bootefi_bootmgr_exec(void)
 448 {
 449         struct efi_device_path *device_path, *file_path;
 450         void *addr;
 451         efi_status_t r;
 452
 453         addr = efi_bootmgr_load(&device_path, &file_path);
 454         if (!addr)
 455                 return 1;
 456
 457         printf("## Starting EFI application at %p ...\n", addr);
 458         r = do_bootefi_exec(addr, device_path, file_path);
 459         printf("## Application terminated, r = %lu\n",
 460                r & ~EFI_ERROR_MASK);
 461
 462         if (r != EFI_SUCCESS)
 463                 return 1;
 464
 465         return 0;
 466 }
 467
 468 /* Interpreter command to boot an arbitrary EFI image from memory */
 469 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 470 {
 471         unsigned long addr;
 472         char *saddr;
 473         efi_status_t r;
 474         unsigned long fdt_addr;
 475
 476         /* Allow unaligned memory access */
 477         allow_unaligned();
 478
 479         /* Initialize EFI drivers */
 480         r = efi_init_obj_list();
 481         if (r != EFI_SUCCESS) {
 482                 printf("Error: Cannot set up EFI drivers, r = %lu\n",
 483                        r & ~EFI_ERROR_MASK);
 484                 return CMD_RET_FAILURE;
 485         }
 486
 487         if (argc < 2)
 488                 return CMD_RET_USAGE;
 489
 490         if (argc > 2) {
 491                 fdt_addr = simple_strtoul(argv[2], NULL, 16);
 492                 if (!fdt_addr && *argv[2] != '0')
 493                         return CMD_RET_USAGE;
 494                 /* Install device tree */
 495                 r = efi_install_fdt(fdt_addr);
 496                 if (r != EFI_SUCCESS) {
 497                         printf("ERROR: failed to install device tree\n");
 498                         return CMD_RET_FAILURE;
 499                 }
 500         } else {
 501                 /* Remove device tree. EFI_NOT_FOUND can be ignored here */
 502                 efi_install_configuration_table(&efi_guid_fdt, NULL);
 503                 printf("WARNING: booting without device tree\n");
 504         }
 505 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 506         if (!strcmp(argv[1], "hello")) {
 507                 ulong size = __efi_helloworld_end - __efi_helloworld_begin;
 508
 509                 saddr = env_get("loadaddr");
 510                 if (saddr)
 511                         addr = simple_strtoul(saddr, NULL, 16);
 512                 else
 513                         addr = CONFIG_SYS_LOAD_ADDR;
 514                 memcpy(map_sysmem(addr, size), __efi_helloworld_begin, size);
 515         } else
 516 #endif
 517 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 518         if (!strcmp(argv[1], "selftest")) {
 519                 struct efi_loaded_image_obj *image_obj;
 520                 struct efi_loaded_image *loaded_image_info;
 521
 522                 if (bootefi_test_prepare(&image_obj, &loaded_image_info,
 523                                          "\\selftest", (uintptr_t)&efi_selftest,
 524                                          "efi_selftest"))
 525                         return CMD_RET_FAILURE;
 526
 527                 /* Execute the test */
 528                 r = efi_selftest(&image_obj->header, &systab);
 529                 bootefi_run_finish(image_obj, loaded_image_info);
 530                 return r != EFI_SUCCESS;
 531         } else
 532 #endif
 533         if (!strcmp(argv[1], "bootmgr")) {
 534                 return do_bootefi_bootmgr_exec();
 535         } else {
 536                 saddr = argv[1];
 537
 538                 addr = simple_strtoul(saddr, NULL, 16);
 539                 /* Check that a numeric value was passed */
 540                 if (!addr && *saddr != '0')
 541                         return CMD_RET_USAGE;
 542
 543         }
 544
 545         printf("## Starting EFI application at %08lx ...\n", addr);
 546         r = do_bootefi_exec(map_sysmem(addr, 0), bootefi_device_path,
 547                             bootefi_image_path);
 548         printf("## Application terminated, r = %lu\n",
 549                r & ~EFI_ERROR_MASK);
 550
 551         if (r != EFI_SUCCESS)
 552                 return 1;
 553         else
 554                 return 0;
 555 }
 556
 557 #ifdef CONFIG_SYS_LONGHELP
 558 static char bootefi_help_text[] =
 559         "<image address> [fdt address]\n"
 560         "  - boot EFI payload stored at address <image address>.\n"
 561         "    If specified, the device tree located at <fdt address> gets\n"
 562         "    exposed as EFI configuration table.\n"
 563 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 564         "bootefi hello\n"
 565         "  - boot a sample Hello World application stored within U-Boot\n"
 566 #endif
 567 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 568         "bootefi selftest [fdt address]\n"
 569         "  - boot an EFI selftest application stored within U-Boot\n"
 570         "    Use environment variable efi_selftest to select a single test.\n"
 571         "    Use 'setenv efi_selftest list' to enumerate all tests.\n"
 572 #endif
 573         "bootefi bootmgr [fdt addr]\n"
 574         "  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
 575         "\n"
 576         "    If specified, the device tree located at <fdt address> gets\n"
 577         "    exposed as EFI configuration table.\n";
 578 #endif
 579
 580 U_BOOT_CMD(
 581         bootefi, 3, 0, do_bootefi,
 582         "Boots an EFI payload from memory",
 583         bootefi_help_text
 584 );
 585
 586 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 587 {
 588         struct efi_device_path *device, *image;
 589         efi_status_t ret;
 590
 591         /* efi_set_bootdev is typically called repeatedly, recover memory */
 592         efi_free_pool(bootefi_device_path);
 593         efi_free_pool(bootefi_image_path);
 594
 595         ret = efi_dp_from_name(dev, devnr, path, &device, &image);
 596         if (ret == EFI_SUCCESS) {
 597                 bootefi_device_path = device;
 598                 bootefi_image_path = image;
 599         } else {
 600                 bootefi_device_path = NULL;
 601                 bootefi_image_path = NULL;
 602         }
 603 }