cmd/avb.c

   1
   2 /*
   3  * (C) Copyright 2018, Linaro Limited
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <avb_verify.h>
   9 #include <command.h>
  10 #include <image.h>
  11 #include <malloc.h>
  12 #include <mmc.h>
  13
  14 #define AVB_BOOTARGS    "avb_bootargs"
  15 static struct AvbOps *avb_ops;
  16
  17 static const char * const requested_partitions[] = {"boot",
  18                                              "system",
  19                                              "vendor",
  20                                              NULL};
  21
  22 int do_avb_init(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  23 {
  24         unsigned long mmc_dev;
  25
  26         if (argc != 2)
  27                 return CMD_RET_USAGE;
  28
  29         mmc_dev = simple_strtoul(argv[1], NULL, 16);
  30
  31         if (avb_ops)
  32                 avb_ops_free(avb_ops);
  33
  34         avb_ops = avb_ops_alloc(mmc_dev);
  35         if (avb_ops)
  36                 return CMD_RET_SUCCESS;
  37
  38         printf("Failed to initialize avb2\n");
  39
  40         return CMD_RET_FAILURE;
  41 }
  42
  43 int do_avb_read_part(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  44 {
  45         const char *part;
  46         s64 offset;
  47         size_t bytes, bytes_read = 0;
  48         void *buffer;
  49
  50         if (!avb_ops) {
  51                 printf("AVB 2.0 is not initialized, please run 'avb init'\n");
  52                 return CMD_RET_USAGE;
  53         }
  54
  55         if (argc != 5)
  56                 return CMD_RET_USAGE;
  57
  58         part = argv[1];
  59         offset = simple_strtoul(argv[2], NULL, 16);
  60         bytes = simple_strtoul(argv[3], NULL, 16);
  61         buffer = (void *)simple_strtoul(argv[4], NULL, 16);
  62
  63         if (avb_ops->read_from_partition(avb_ops, part, offset, bytes,
  64                                          buffer, &bytes_read) ==
  65                                          AVB_IO_RESULT_OK) {
  66                 printf("Read %zu bytes\n", bytes_read);
  67                 return CMD_RET_SUCCESS;
  68         }
  69
  70         printf("Failed to read from partition\n");
  71
  72         return CMD_RET_FAILURE;
  73 }
  74
  75 int do_avb_read_part_hex(cmd_tbl_t *cmdtp, int flag, int argc,
  76                          char *const argv[])
  77 {
  78         const char *part;
  79         s64 offset;
  80         size_t bytes, bytes_read = 0;
  81         char *buffer;
  82
  83         if (!avb_ops) {
  84                 printf("AVB 2.0 is not initialized, please run 'avb init'\n");
  85                 return CMD_RET_USAGE;
  86         }
  87
  88         if (argc != 4)
  89                 return CMD_RET_USAGE;
  90
  91         part = argv[1];
  92         offset = simple_strtoul(argv[2], NULL, 16);
  93         bytes = simple_strtoul(argv[3], NULL, 16);
  94
  95         buffer = malloc(bytes);
  96         if (!buffer) {
  97                 printf("Failed to tlb_allocate buffer for data\n");
  98                 return CMD_RET_FAILURE;
  99         }
 100         memset(buffer, 0, bytes);
 101
 102         if (avb_ops->read_from_partition(avb_ops, part, offset, bytes, buffer,
 103                                          &bytes_read) == AVB_IO_RESULT_OK) {
 104                 printf("Requested %zu, read %zu bytes\n", bytes, bytes_read);
 105                 printf("Data: ");
 106                 for (int i = 0; i < bytes_read; i++)
 107                         printf("%02X", buffer[i]);
 108
 109                 printf("\n");
 110
 111                 free(buffer);
 112                 return CMD_RET_SUCCESS;
 113         }
 114
 115         printf("Failed to read from partition\n");
 116
 117         free(buffer);
 118         return CMD_RET_FAILURE;
 119 }
 120
 121 int do_avb_write_part(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 122 {
 123         const char *part;
 124         s64 offset;
 125         size_t bytes;
 126         void *buffer;
 127
 128         if (!avb_ops) {
 129                 printf("AVB 2.0 is not initialized, run 'avb init' first\n");
 130                 return CMD_RET_FAILURE;
 131         }
 132
 133         if (argc != 5)
 134                 return CMD_RET_USAGE;
 135
 136         part = argv[1];
 137         offset = simple_strtoul(argv[2], NULL, 16);
 138         bytes = simple_strtoul(argv[3], NULL, 16);
 139         buffer = (void *)simple_strtoul(argv[4], NULL, 16);
 140
 141         if (avb_ops->write_to_partition(avb_ops, part, offset, bytes, buffer) ==
 142             AVB_IO_RESULT_OK) {
 143                 printf("Wrote %zu bytes\n", bytes);
 144                 return CMD_RET_SUCCESS;
 145         }
 146
 147         printf("Failed to write in partition\n");
 148
 149         return CMD_RET_FAILURE;
 150 }
 151
 152 int do_avb_read_rb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 153 {
 154         size_t index;
 155         u64 rb_idx;
 156
 157         if (!avb_ops) {
 158                 printf("AVB 2.0 is not initialized, run 'avb init' first\n");
 159                 return CMD_RET_FAILURE;
 160         }
 161
 162         if (argc != 2)
 163                 return CMD_RET_USAGE;
 164
 165         index = (size_t)simple_strtoul(argv[1], NULL, 16);
 166
 167         if (avb_ops->read_rollback_index(avb_ops, index, &rb_idx) ==
 168             AVB_IO_RESULT_OK) {
 169                 printf("Rollback index: %llx\n", rb_idx);
 170                 return CMD_RET_SUCCESS;
 171         }
 172
 173         printf("Failed to read rollback index\n");
 174
 175         return CMD_RET_FAILURE;
 176 }
 177
 178 int do_avb_write_rb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 179 {
 180         size_t index;
 181         u64 rb_idx;
 182
 183         if (!avb_ops) {
 184                 printf("AVB 2.0 is not initialized, run 'avb init' first\n");
 185                 return CMD_RET_FAILURE;
 186         }
 187
 188         if (argc != 3)
 189                 return CMD_RET_USAGE;
 190
 191         index = (size_t)simple_strtoul(argv[1], NULL, 16);
 192         rb_idx = simple_strtoul(argv[2], NULL, 16);
 193
 194         if (avb_ops->write_rollback_index(avb_ops, index, rb_idx) ==
 195             AVB_IO_RESULT_OK)
 196                 return CMD_RET_SUCCESS;
 197
 198         printf("Failed to write rollback index\n");
 199
 200         return CMD_RET_FAILURE;
 201 }
 202
 203 int do_avb_get_uuid(cmd_tbl_t *cmdtp, int flag,
 204                     int argc, char * const argv[])
 205 {
 206         const char *part;
 207         char buffer[UUID_STR_LEN + 1];
 208
 209         if (!avb_ops) {
 210                 printf("AVB 2.0 is not initialized, run 'avb init' first\n");
 211                 return CMD_RET_FAILURE;
 212         }
 213
 214         if (argc != 2)
 215                 return CMD_RET_USAGE;
 216
 217         part = argv[1];
 218
 219         if (avb_ops->get_unique_guid_for_partition(avb_ops, part, buffer,
 220                                                    UUID_STR_LEN + 1) ==
 221                                                    AVB_IO_RESULT_OK) {
 222                 printf("'%s' UUID: %s\n", part, buffer);
 223                 return CMD_RET_SUCCESS;
 224         }
 225
 226         printf("Failed to read UUID\n");
 227
 228         return CMD_RET_FAILURE;
 229 }
 230
 231 int do_avb_verify_part(cmd_tbl_t *cmdtp, int flag,
 232                        int argc, char *const argv[])
 233 {
 234         AvbSlotVerifyResult slot_result;
 235         AvbSlotVerifyData *out_data;
 236         char *cmdline;
 237         char *extra_args;
 238
 239         bool unlocked = false;
 240         int res = CMD_RET_FAILURE;
 241
 242         if (!avb_ops) {
 243                 printf("AVB 2.0 is not initialized, run 'avb init' first\n");
 244                 return CMD_RET_FAILURE;
 245         }
 246
 247         if (argc != 1)
 248                 return CMD_RET_USAGE;
 249
 250         printf("## Android Verified Boot 2.0 version %s\n",
 251                avb_version_string());
 252
 253         if (avb_ops->read_is_device_unlocked(avb_ops, &unlocked) !=
 254             AVB_IO_RESULT_OK) {
 255                 printf("Can't determine device lock state.\n");
 256                 return CMD_RET_FAILURE;
 257         }
 258
 259         slot_result =
 260                 avb_slot_verify(avb_ops,
 261                                 requested_partitions,
 262                                 "",
 263                                 unlocked,
 264                                 AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
 265                                 &out_data);
 266
 267         switch (slot_result) {
 268         case AVB_SLOT_VERIFY_RESULT_OK:
 269                 /* Until we don't have support of changing unlock states, we
 270                  * assume that we are by default in locked state.
 271                  * So in this case we can boot only when verification is
 272                  * successful; we also supply in cmdline GREEN boot state
 273                  */
 274                 printf("Verification passed successfully\n");
 275
 276                 /* export additional bootargs to AVB_BOOTARGS env var */
 277
 278                 extra_args = avb_set_state(avb_ops, AVB_GREEN);
 279                 if (extra_args)
 280                         cmdline = append_cmd_line(out_data->cmdline,
 281                                                   extra_args);
 282                 else
 283                         cmdline = out_data->cmdline;
 284
 285                 env_set(AVB_BOOTARGS, cmdline);
 286
 287                 res = CMD_RET_SUCCESS;
 288                 break;
 289         case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION:
 290                 printf("Verification failed\n");
 291                 break;
 292         case AVB_SLOT_VERIFY_RESULT_ERROR_IO:
 293                 printf("I/O error occurred during verification\n");
 294                 break;
 295         case AVB_SLOT_VERIFY_RESULT_ERROR_OOM:
 296                 printf("OOM error occurred during verification\n");
 297                 break;
 298         case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA:
 299                 printf("Corrupted dm-verity metadata detected\n");
 300                 break;
 301         case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION:
 302                 printf("Unsupported version avbtool was used\n");
 303                 break;
 304         case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX:
 305                 printf("Checking rollback index failed\n");
 306                 break;
 307         case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED:
 308                 printf("Public key was rejected\n");
 309                 break;
 310         default:
 311                 printf("Unknown error occurred\n");
 312         }
 313
 314         return res;
 315 }
 316
 317 int do_avb_is_unlocked(cmd_tbl_t *cmdtp, int flag,
 318                        int argc, char * const argv[])
 319 {
 320         bool unlock;
 321
 322         if (!avb_ops) {
 323                 printf("AVB not initialized, run 'avb init' first\n");
 324                 return CMD_RET_FAILURE;
 325         }
 326
 327         if (argc != 1) {
 328                 printf("--%s(-1)\n", __func__);
 329                 return CMD_RET_USAGE;
 330         }
 331
 332         if (avb_ops->read_is_device_unlocked(avb_ops, &unlock) ==
 333             AVB_IO_RESULT_OK) {
 334                 printf("Unlocked = %d\n", unlock);
 335                 return CMD_RET_SUCCESS;
 336         }
 337
 338         printf("Can't determine device lock state.\n");
 339
 340         return CMD_RET_FAILURE;
 341 }
 342
 343 static cmd_tbl_t cmd_avb[] = {
 344         U_BOOT_CMD_MKENT(init, 2, 0, do_avb_init, "", ""),
 345         U_BOOT_CMD_MKENT(read_rb, 2, 0, do_avb_read_rb, "", ""),
 346         U_BOOT_CMD_MKENT(write_rb, 3, 0, do_avb_write_rb, "", ""),
 347         U_BOOT_CMD_MKENT(is_unlocked, 1, 0, do_avb_is_unlocked, "", ""),
 348         U_BOOT_CMD_MKENT(get_uuid, 2, 0, do_avb_get_uuid, "", ""),
 349         U_BOOT_CMD_MKENT(read_part, 5, 0, do_avb_read_part, "", ""),
 350         U_BOOT_CMD_MKENT(read_part_hex, 4, 0, do_avb_read_part_hex, "", ""),
 351         U_BOOT_CMD_MKENT(write_part, 5, 0, do_avb_write_part, "", ""),
 352         U_BOOT_CMD_MKENT(verify, 1, 0, do_avb_verify_part, "", ""),
 353 };
 354
 355 static int do_avb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 356 {
 357         cmd_tbl_t *cp;
 358
 359         cp = find_cmd_tbl(argv[1], cmd_avb, ARRAY_SIZE(cmd_avb));
 360
 361         argc--;
 362         argv++;
 363
 364         if (!cp || argc > cp->maxargs)
 365                 return CMD_RET_USAGE;
 366
 367         if (flag == CMD_FLAG_REPEAT)
 368                 return CMD_RET_FAILURE;
 369
 370         return cp->cmd(cmdtp, flag, argc, argv);
 371 }
 372
 373 U_BOOT_CMD(
 374         avb, 29, 0, do_avb,
 375         "Provides commands for testing Android Verified Boot 2.0 functionality",
 376         "init <dev> - initialize avb2 for <dev>\n"
 377         "avb read_rb <num> - read rollback index at location <num>\n"
 378         "avb write_rb <num> <rb> - write rollback index <rb> to <num>\n"
 379         "avb is_unlocked - returns unlock status of the device\n"
 380         "avb get_uuid <partname> - read and print uuid of partition <part>\n"
 381         "avb read_part <partname> <offset> <num> <addr> - read <num> bytes from\n"
 382         "    partition <partname> to buffer <addr>\n"
 383         "avb read_part_hex <partname> <offset> <num> - read <num> bytes from\n"
 384         "    partition <partname> and print to stdout\n"
 385         "avb write_part <partname> <offset> <num> <addr> - write <num> bytes to\n"
 386         "    <partname> by <offset> using data from <addr>\n"
 387         "avb verify - run verification process using hash data\n"
 388         "    from vbmeta structure\n"
 389         );