lib/efi_loader/efi_tcg2.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Defines APIs that allow an OS to interact with UEFI firmware to query
   4  * information about the device.
   5  * https://trustedcomputinggroup.org/resource/tcg-efi-protocol-specification/
   6  *
   7  * Copyright (c) 2020, Linaro Limited
   8  */
   9
  10 #define LOG_CATEGORY LOGC_EFI
  11 #include <common.h>
  12 #include <dm.h>
  13 #include <efi_loader.h>
  14 #include <efi_variable.h>
  15 #include <efi_tcg2.h>
  16 #include <log.h>
  17 #include <malloc.h>
  18 #include <smbios.h>
  19 #include <version_string.h>
  20 #include <tpm-v2.h>
  21 #include <tpm_api.h>
  22 #include <u-boot/hash-checksum.h>
  23 #include <u-boot/sha1.h>
  24 #include <u-boot/sha256.h>
  25 #include <u-boot/sha512.h>
  26 #include <linux/unaligned/be_byteshift.h>
  27 #include <linux/unaligned/le_byteshift.h>
  28 #include <linux/unaligned/generic.h>
  29 #include <hexdump.h>
  30
  31 /**
  32  * struct event_log_buffer - internal eventlog management structure
  33  *
  34  * @buffer:             eventlog buffer
  35  * @final_buffer:       finalevent config table buffer
  36  * @pos:                current position of 'buffer'
  37  * @final_pos:          current position of 'final_buffer'
  38  * @get_event_called:   true if GetEventLog has been invoked at least once
  39  * @ebs_called:         true if ExitBootServices has been invoked
  40  * @truncated:          true if the 'buffer' is truncated
  41  */
  42 struct event_log_buffer {
  43         void *buffer;
  44         void *final_buffer;
  45         size_t pos; /* eventlog position */
  46         size_t final_pos; /* final events config table position */
  47         size_t last_event_size;
  48         bool get_event_called;
  49         bool ebs_called;
  50         bool truncated;
  51 };
  52
  53 static struct event_log_buffer event_log;
  54 static bool tcg2_efi_app_invoked;
  55 /*
  56  * When requesting TPM2_CAP_TPM_PROPERTIES the value is on a standard offset.
  57  * Since the current tpm2_get_capability() response buffers starts at
  58  * 'union tpmu_capabilities data' of 'struct tpms_capability_data', calculate
  59  * the response size and offset once for all consumers
  60  */
  61 #define TPM2_RESPONSE_BUFFER_SIZE (sizeof(struct tpms_capability_data) - \
  62                                    offsetof(struct tpms_capability_data, data))
  63 #define properties_offset (offsetof(struct tpml_tagged_tpm_property, tpm_property) + \
  64                            offsetof(struct tpms_tagged_property, value))
  65
  66 static const efi_guid_t efi_guid_tcg2_protocol = EFI_TCG2_PROTOCOL_GUID;
  67 static const efi_guid_t efi_guid_final_events = EFI_TCG2_FINAL_EVENTS_TABLE_GUID;
  68
  69 struct digest_info {
  70         u16 hash_alg;
  71         u32 hash_mask;
  72         u16 hash_len;
  73 };
  74
  75 static const struct digest_info hash_algo_list[] = {
  76         {
  77                 TPM2_ALG_SHA1,
  78                 EFI_TCG2_BOOT_HASH_ALG_SHA1,
  79                 TPM2_SHA1_DIGEST_SIZE,
  80         },
  81         {
  82                 TPM2_ALG_SHA256,
  83                 EFI_TCG2_BOOT_HASH_ALG_SHA256,
  84                 TPM2_SHA256_DIGEST_SIZE,
  85         },
  86         {
  87                 TPM2_ALG_SHA384,
  88                 EFI_TCG2_BOOT_HASH_ALG_SHA384,
  89                 TPM2_SHA384_DIGEST_SIZE,
  90         },
  91         {
  92                 TPM2_ALG_SHA512,
  93                 EFI_TCG2_BOOT_HASH_ALG_SHA512,
  94                 TPM2_SHA512_DIGEST_SIZE,
  95         },
  96 };
  97
  98 struct variable_info {
  99         const u16       *name;
 100         bool            accept_empty;
 101         u32             pcr_index;
 102 };
 103
 104 static struct variable_info secure_variables[] = {
 105         {u"SecureBoot",         true,   7},
 106         {u"PK",                 true,   7},
 107         {u"KEK",                true,   7},
 108         {u"db",                 true,   7},
 109         {u"dbx",                true,   7},
 110         {u"dbt",                false,  7},
 111         {u"dbr",                false,  7},
 112         {u"DeployedMode",       false,  1},
 113         {u"AuditMode",          false,  1},
 114 };
 115
 116 #define MAX_HASH_COUNT ARRAY_SIZE(hash_algo_list)
 117
 118 /**
 119  * alg_to_mask - Get a TCG hash mask for algorithms
 120  *
 121  * @hash_alg: TCG defined algorithm
 122  *
 123  * @Return: TCG hashing algorithm bitmaps, 0 if the algorithm is not supported
 124  */
 125 static u32 alg_to_mask(u16 hash_alg)
 126 {
 127         size_t i;
 128
 129         for (i = 0; i < MAX_HASH_COUNT; i++) {
 130                 if (hash_algo_list[i].hash_alg == hash_alg)
 131                         return hash_algo_list[i].hash_mask;
 132         }
 133
 134         return 0;
 135 }
 136
 137 /**
 138  * alg_to_len - Get a TCG hash len for algorithms
 139  *
 140  * @hash_alg: TCG defined algorithm
 141  *
 142  * @Return: len of chosen algorithm, 0 if the algorithm is not supported
 143  */
 144 static u16 alg_to_len(u16 hash_alg)
 145 {
 146         size_t i;
 147
 148         for (i = 0; i < MAX_HASH_COUNT; i++) {
 149                 if (hash_algo_list[i].hash_alg == hash_alg)
 150                         return hash_algo_list[i].hash_len;
 151         }
 152
 153         return 0;
 154 }
 155
 156 static u32 tcg_event_final_size(struct tpml_digest_values *digest_list)
 157 {
 158         u32 len;
 159         size_t i;
 160
 161         len = offsetof(struct tcg_pcr_event2, digests);
 162         len += offsetof(struct tpml_digest_values, digests);
 163         for (i = 0; i < digest_list->count; i++) {
 164                 u16 hash_alg = digest_list->digests[i].hash_alg;
 165
 166                 len += offsetof(struct tpmt_ha, digest);
 167                 len += alg_to_len(hash_alg);
 168         }
 169         len += sizeof(u32); /* tcg_pcr_event2 event_size*/
 170
 171         return len;
 172 }
 173
 174 /* tcg2_pcr_extend - Extend PCRs for a TPM2 device for a given tpml_digest_values
 175  *
 176  * @dev:                device
 177  * @digest_list:        list of digest algorithms to extend
 178  *
 179  * @Return: status code
 180  */
 181 static efi_status_t tcg2_pcr_extend(struct udevice *dev, u32 pcr_index,
 182                                     struct tpml_digest_values *digest_list)
 183 {
 184         u32 rc;
 185         size_t i;
 186
 187         for (i = 0; i < digest_list->count; i++) {
 188                 u32 alg = digest_list->digests[i].hash_alg;
 189
 190                 rc = tpm2_pcr_extend(dev, pcr_index, alg,
 191                                      (u8 *)&digest_list->digests[i].digest,
 192                                      alg_to_len(alg));
 193                 if (rc) {
 194                         EFI_PRINT("Failed to extend PCR\n");
 195                         return EFI_DEVICE_ERROR;
 196                 }
 197         }
 198
 199         return EFI_SUCCESS;
 200 }
 201
 202 /* put_event - Append an agile event to an eventlog
 203  *
 204  * @pcr_index:          PCR index
 205  * @event_type:         type of event added
 206  * @digest_list:        list of digest algorithms to add
 207  * @size:               size of event
 208  * @event:              event to add
 209  * @log:                log buffer to append the event
 210  *
 211  */
 212 static void put_event(u32 pcr_index, u32 event_type,
 213                       struct tpml_digest_values *digest_list, u32 size,
 214                       u8 event[], void *log)
 215 {
 216         size_t pos;
 217         size_t i;
 218         u32 event_size;
 219
 220         /*
 221          * size refers to the length of event[] only, we need to check against
 222          * the final tcg_pcr_event2 size
 223          */
 224         event_size = size + tcg_event_final_size(digest_list);
 225
 226         put_unaligned_le32(pcr_index, log);
 227         pos = offsetof(struct tcg_pcr_event2, event_type);
 228         put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos));
 229         pos = offsetof(struct tcg_pcr_event2, digests); /* count */
 230         put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos));
 231
 232         pos += offsetof(struct tpml_digest_values, digests);
 233         for (i = 0; i < digest_list->count; i++) {
 234                 u16 hash_alg = digest_list->digests[i].hash_alg;
 235                 u8 *digest = (u8 *)&digest_list->digests[i].digest;
 236
 237                 put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos));
 238                 pos += offsetof(struct tpmt_ha, digest);
 239                 memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg));
 240                 pos += alg_to_len(hash_alg);
 241         }
 242
 243         put_unaligned_le32(size, (void *)((uintptr_t)log + pos));
 244         pos += sizeof(u32); /* tcg_pcr_event2 event_size*/
 245         memcpy((void *)((uintptr_t)log + pos), event, size);
 246         pos += size;
 247
 248         /*
 249          * make sure the calculated buffer is what we checked against
 250          * This check should never fail.  It checks the code above is
 251          * calculating the right length for the event we are adding
 252          */
 253         if (pos != event_size)
 254                 log_err("Appending to the EventLog failed\n");
 255 }
 256
 257 /* tcg2_agile_log_append - Append an agile event to an eventlog
 258  *
 259  * @pcr_index:          PCR index
 260  * @event_type:         type of event added
 261  * @digest_list:        list of digest algorithms to add
 262  * @size:               size of event
 263  * @event:              event to add
 264  * @log:                log buffer to append the event
 265  *
 266  * @Return: status code
 267  */
 268 static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type,
 269                                           struct tpml_digest_values *digest_list,
 270                                           u32 size, u8 event[])
 271 {
 272         void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos);
 273         u32 event_size = size + tcg_event_final_size(digest_list);
 274         struct efi_tcg2_final_events_table *final_event;
 275         efi_status_t ret = EFI_SUCCESS;
 276
 277         /* if ExitBootServices hasn't been called update the normal log */
 278         if (!event_log.ebs_called) {
 279                 if (event_log.truncated ||
 280                     event_log.pos + event_size > TPM2_EVENT_LOG_SIZE) {
 281                         event_log.truncated = true;
 282                         return EFI_VOLUME_FULL;
 283                 }
 284                 put_event(pcr_index, event_type, digest_list, size, event, log);
 285                 event_log.pos += event_size;
 286                 event_log.last_event_size = event_size;
 287         }
 288
 289         if (!event_log.get_event_called)
 290                 return ret;
 291
 292         /* if GetEventLog has been called update FinalEventLog as well */
 293         if (event_log.final_pos + event_size > TPM2_EVENT_LOG_SIZE)
 294                 return EFI_VOLUME_FULL;
 295
 296         log = (void *)((uintptr_t)event_log.final_buffer + event_log.final_pos);
 297         put_event(pcr_index, event_type, digest_list, size, event, log);
 298
 299         final_event = event_log.final_buffer;
 300         final_event->number_of_events++;
 301         event_log.final_pos += event_size;
 302
 303         return ret;
 304 }
 305
 306 /**
 307  * platform_get_tpm_device() - retrieve TPM device
 308  *
 309  * This function retrieves the udevice implementing a TPM
 310  *
 311  * This function may be overridden if special initialization is needed.
 312  *
 313  * @dev:        udevice
 314  * Return:      status code
 315  */
 316 __weak efi_status_t platform_get_tpm2_device(struct udevice **dev)
 317 {
 318         for_each_tpm_device(*dev) {
 319                 /* Only support TPMv2 devices */
 320                 if (tpm_get_version(*dev) == TPM_V2)
 321                         return EFI_SUCCESS;
 322         }
 323
 324         return EFI_NOT_FOUND;
 325 }
 326
 327 /**
 328  * tpm2_get_max_command_size() - get the supported max command size
 329  *
 330  * @dev:                TPM device
 331  * @max_command_size:   output buffer for the size
 332  *
 333  * Return: 0 on success, -1 on error
 334  */
 335 static int tpm2_get_max_command_size(struct udevice *dev, u16 *max_command_size)
 336 {
 337         u8 response[TPM2_RESPONSE_BUFFER_SIZE];
 338         u32 ret;
 339
 340         memset(response, 0, sizeof(response));
 341         ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
 342                                   TPM2_PT_MAX_COMMAND_SIZE, response, 1);
 343         if (ret)
 344                 return -1;
 345
 346         *max_command_size = (uint16_t)get_unaligned_be32(response +
 347                                                          properties_offset);
 348
 349         return 0;
 350 }
 351
 352 /**
 353  * tpm2_get_max_response_size() - get the supported max response size
 354  *
 355  * @dev:                TPM device
 356  * @max_response_size:  output buffer for the size
 357  *
 358  * Return: 0 on success, -1 on error
 359  */
 360 static int tpm2_get_max_response_size(struct udevice *dev,
 361                                       u16 *max_response_size)
 362 {
 363         u8 response[TPM2_RESPONSE_BUFFER_SIZE];
 364         u32 ret;
 365
 366         memset(response, 0, sizeof(response));
 367         ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
 368                                   TPM2_PT_MAX_RESPONSE_SIZE, response, 1);
 369         if (ret)
 370                 return -1;
 371
 372         *max_response_size = (uint16_t)get_unaligned_be32(response +
 373                                                           properties_offset);
 374
 375         return 0;
 376 }
 377
 378 /**
 379  * tpm2_get_manufacturer_id() - get the manufacturer ID
 380  *
 381  * @dev:                TPM device
 382  * @manufacturer_id:    output buffer for the id
 383  *
 384  * Return: 0 on success, -1 on error
 385  */
 386 static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id)
 387 {
 388         u8 response[TPM2_RESPONSE_BUFFER_SIZE];
 389         u32 ret;
 390
 391         memset(response, 0, sizeof(response));
 392         ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
 393                                   TPM2_PT_MANUFACTURER, response, 1);
 394         if (ret)
 395                 return -1;
 396
 397         *manufacturer_id = get_unaligned_be32(response + properties_offset);
 398
 399         return 0;
 400 }
 401
 402 /**
 403  * tpm2_get_num_pcr() - get the number of PCRs
 404  *
 405  * @dev:                TPM device
 406  * @manufacturer_id:    output buffer for the number
 407  *
 408  * Return: 0 on success, -1 on error
 409  */
 410 static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr)
 411 {
 412         u8 response[TPM2_RESPONSE_BUFFER_SIZE];
 413         u32 ret;
 414
 415         memset(response, 0, sizeof(response));
 416         ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES,
 417                                   TPM2_PT_PCR_COUNT, response, 1);
 418         if (ret)
 419                 return -1;
 420
 421         *num_pcr = get_unaligned_be32(response + properties_offset);
 422         if (*num_pcr > TPM2_MAX_PCRS)
 423                 return -1;
 424
 425         return 0;
 426 }
 427
 428 /**
 429  * is_active_pcr() - Check if a supported algorithm is active
 430  *
 431  * @dev:                TPM device
 432  * @selection:          struct of PCR information
 433  *
 434  * Return: true if PCR is active
 435  */
 436 static bool is_active_pcr(struct tpms_pcr_selection *selection)
 437 {
 438         int i;
 439         /*
 440          * check the pcr_select. If at least one of the PCRs supports the
 441          * algorithm add it on the active ones
 442          */
 443         for (i = 0; i < selection->size_of_select; i++) {
 444                 if (selection->pcr_select[i])
 445                         return true;
 446         }
 447
 448         return false;
 449 }
 450
 451 /**
 452  * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks
 453  *
 454  * @dev:                TPM device
 455  * @supported_pcr:      bitmask with the algorithms supported
 456  * @active_pcr:         bitmask with the active algorithms
 457  * @pcr_banks:          number of PCR banks
 458  *
 459  * Return: 0 on success, -1 on error
 460  */
 461 static int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr,
 462                              u32 *active_pcr, u32 *pcr_banks)
 463 {
 464         u8 response[TPM2_RESPONSE_BUFFER_SIZE];
 465         struct tpml_pcr_selection pcrs;
 466         u32 ret, num_pcr;
 467         size_t i;
 468         int tpm_ret;
 469
 470         *supported_pcr = 0;
 471         *active_pcr = 0;
 472         *pcr_banks = 0;
 473         memset(response, 0, sizeof(response));
 474         ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1);
 475         if (ret)
 476                 goto out;
 477
 478         pcrs.count = get_unaligned_be32(response);
 479         /*
 480          * We only support 5 algorithms for now so check against that
 481          * instead of TPM2_NUM_PCR_BANKS
 482          */
 483         if (pcrs.count > MAX_HASH_COUNT || pcrs.count < 1)
 484                 goto out;
 485
 486         tpm_ret = tpm2_get_num_pcr(dev, &num_pcr);
 487         if (tpm_ret)
 488                 goto out;
 489
 490         for (i = 0; i < pcrs.count; i++) {
 491                 /*
 492                  * Definition of TPMS_PCR_SELECTION Structure
 493                  * hash: u16
 494                  * size_of_select: u8
 495                  * pcr_select: u8 array
 496                  *
 497                  * The offsets depend on the number of the device PCRs
 498                  * so we have to calculate them based on that
 499                  */
 500                 u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) +
 501                         i * offsetof(struct tpms_pcr_selection, pcr_select) +
 502                         i * ((num_pcr + 7) / 8);
 503                 u32 size_select_offset =
 504                         hash_offset + offsetof(struct tpms_pcr_selection,
 505                                                size_of_select);
 506                 u32 pcr_select_offset =
 507                         hash_offset + offsetof(struct tpms_pcr_selection,
 508                                                pcr_select);
 509
 510                 pcrs.selection[i].hash =
 511                         get_unaligned_be16(response + hash_offset);
 512                 pcrs.selection[i].size_of_select =
 513                         __get_unaligned_be(response + size_select_offset);
 514                 if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX)
 515                         goto out;
 516                 /* copy the array of pcr_select */
 517                 memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset,
 518                        pcrs.selection[i].size_of_select);
 519         }
 520
 521         for (i = 0; i < pcrs.count; i++) {
 522                 u32 hash_mask = alg_to_mask(pcrs.selection[i].hash);
 523
 524                 if (hash_mask) {
 525                         *supported_pcr |= hash_mask;
 526                         if (is_active_pcr(&pcrs.selection[i]))
 527                                 *active_pcr |= hash_mask;
 528                 } else {
 529                         EFI_PRINT("Unknown algorithm %x\n", pcrs.selection[i].hash);
 530                 }
 531         }
 532
 533         *pcr_banks = pcrs.count;
 534
 535         return 0;
 536 out:
 537         return -1;
 538 }
 539
 540 /**
 541  * __get_active_pcr_banks() - returns the currently active PCR banks
 542  *
 543  * @active_pcr_banks:           pointer for receiving the bitmap of currently
 544  *                              active PCR banks
 545  *
 546  * Return:      status code
 547  */
 548 static efi_status_t __get_active_pcr_banks(u32 *active_pcr_banks)
 549 {
 550         struct udevice *dev;
 551         u32 active = 0, supported = 0, pcr_banks = 0;
 552         efi_status_t ret;
 553         int err;
 554
 555         ret = platform_get_tpm2_device(&dev);
 556         if (ret != EFI_SUCCESS)
 557                 goto out;
 558
 559         err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks);
 560         if (err) {
 561                 ret = EFI_DEVICE_ERROR;
 562                 goto out;
 563         }
 564
 565         *active_pcr_banks = active;
 566
 567 out:
 568         return ret;
 569 }
 570
 571 /* tcg2_create_digest - create a list of digests of the supported PCR banks
 572  *                      for a given memory range
 573  *
 574  * @input:              input memory
 575  * @length:             length of buffer to calculate the digest
 576  * @digest_list:        list of digests to fill in
 577  *
 578  * Return:              status code
 579  */
 580 static efi_status_t tcg2_create_digest(const u8 *input, u32 length,
 581                                        struct tpml_digest_values *digest_list)
 582 {
 583         sha1_context ctx;
 584         sha256_context ctx_256;
 585         sha512_context ctx_512;
 586         u8 final[TPM2_SHA512_DIGEST_SIZE];
 587         efi_status_t ret;
 588         u32 active;
 589         size_t i;
 590
 591         ret = __get_active_pcr_banks(&active);
 592         if (ret != EFI_SUCCESS)
 593                 return ret;
 594
 595         digest_list->count = 0;
 596         for (i = 0; i < MAX_HASH_COUNT; i++) {
 597                 u16 hash_alg = hash_algo_list[i].hash_alg;
 598
 599                 if (!(active & alg_to_mask(hash_alg)))
 600                         continue;
 601                 switch (hash_alg) {
 602                 case TPM2_ALG_SHA1:
 603                         sha1_starts(&ctx);
 604                         sha1_update(&ctx, input, length);
 605                         sha1_finish(&ctx, final);
 606                         break;
 607                 case TPM2_ALG_SHA256:
 608                         sha256_starts(&ctx_256);
 609                         sha256_update(&ctx_256, input, length);
 610                         sha256_finish(&ctx_256, final);
 611                         break;
 612                 case TPM2_ALG_SHA384:
 613                         sha384_starts(&ctx_512);
 614                         sha384_update(&ctx_512, input, length);
 615                         sha384_finish(&ctx_512, final);
 616                         break;
 617                 case TPM2_ALG_SHA512:
 618                         sha512_starts(&ctx_512);
 619                         sha512_update(&ctx_512, input, length);
 620                         sha512_finish(&ctx_512, final);
 621                         break;
 622                 default:
 623                         EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
 624                         return EFI_INVALID_PARAMETER;
 625                 }
 626                 digest_list->digests[digest_list->count].hash_alg = hash_alg;
 627                 memcpy(&digest_list->digests[digest_list->count].digest, final,
 628                        (u32)alg_to_len(hash_alg));
 629                 digest_list->count++;
 630         }
 631
 632         return EFI_SUCCESS;
 633 }
 634
 635 /**
 636  * efi_tcg2_get_capability() - protocol capability information and state information
 637  *
 638  * @this:               TCG2 protocol instance
 639  * @capability:         caller allocated memory with size field to the size of
 640  *                      the structure allocated
 641
 642  * Return:      status code
 643  */
 644 static efi_status_t EFIAPI
 645 efi_tcg2_get_capability(struct efi_tcg2_protocol *this,
 646                         struct efi_tcg2_boot_service_capability *capability)
 647 {
 648         struct udevice *dev;
 649         efi_status_t efi_ret;
 650         int ret;
 651
 652         EFI_ENTRY("%p, %p", this, capability);
 653
 654         if (!this || !capability) {
 655                 efi_ret = EFI_INVALID_PARAMETER;
 656                 goto out;
 657         }
 658
 659         if (capability->size < BOOT_SERVICE_CAPABILITY_MIN) {
 660                 capability->size = BOOT_SERVICE_CAPABILITY_MIN;
 661                 efi_ret = EFI_BUFFER_TOO_SMALL;
 662                 goto out;
 663         }
 664
 665         if (capability->size < sizeof(*capability)) {
 666                 capability->size = sizeof(*capability);
 667                 efi_ret = EFI_BUFFER_TOO_SMALL;
 668                 goto out;
 669         }
 670
 671         capability->structure_version.major = 1;
 672         capability->structure_version.minor = 1;
 673         capability->protocol_version.major = 1;
 674         capability->protocol_version.minor = 1;
 675
 676         efi_ret = platform_get_tpm2_device(&dev);
 677         if (efi_ret != EFI_SUCCESS) {
 678                 capability->supported_event_logs = 0;
 679                 capability->hash_algorithm_bitmap = 0;
 680                 capability->tpm_present_flag = false;
 681                 capability->max_command_size = 0;
 682                 capability->max_response_size = 0;
 683                 capability->manufacturer_id = 0;
 684                 capability->number_of_pcr_banks = 0;
 685                 capability->active_pcr_banks = 0;
 686
 687                 efi_ret = EFI_SUCCESS;
 688                 goto out;
 689         }
 690
 691         /* We only allow a TPMv2 device to register the EFI protocol */
 692         capability->supported_event_logs = TCG2_EVENT_LOG_FORMAT_TCG_2;
 693
 694         capability->tpm_present_flag = true;
 695
 696         /* Supported and active PCRs */
 697         capability->hash_algorithm_bitmap = 0;
 698         capability->active_pcr_banks = 0;
 699         ret = tpm2_get_pcr_info(dev, &capability->hash_algorithm_bitmap,
 700                                 &capability->active_pcr_banks,
 701                                 &capability->number_of_pcr_banks);
 702         if (ret) {
 703                 efi_ret = EFI_DEVICE_ERROR;
 704                 goto out;
 705         }
 706
 707         /* Max command size */
 708         ret = tpm2_get_max_command_size(dev, &capability->max_command_size);
 709         if (ret) {
 710                 efi_ret = EFI_DEVICE_ERROR;
 711                 goto out;
 712         }
 713
 714         /* Max response size */
 715         ret = tpm2_get_max_response_size(dev, &capability->max_response_size);
 716         if (ret) {
 717                 efi_ret = EFI_DEVICE_ERROR;
 718                 goto out;
 719         }
 720
 721         /* Manufacturer ID */
 722         ret = tpm2_get_manufacturer_id(dev, &capability->manufacturer_id);
 723         if (ret) {
 724                 efi_ret = EFI_DEVICE_ERROR;
 725                 goto out;
 726         }
 727
 728         return EFI_EXIT(EFI_SUCCESS);
 729 out:
 730         return EFI_EXIT(efi_ret);
 731 }
 732
 733 /**
 734  * efi_tcg2_get_eventlog() -    retrieve the the address of an event log and its
 735  *                              last entry
 736  *
 737  * @this:                       TCG2 protocol instance
 738  * @log_format:                 type of event log format
 739  * @event_log_location:         pointer to the memory address of the event log
 740  * @event_log_last_entry:       pointer to the address of the start of the last
 741  *                              entry in the event log in memory, if log contains
 742  *                              more than 1 entry
 743  * @event_log_truncated:        set to true, if the Event Log is missing at i
 744  *                              least one entry
 745  *
 746  * Return:      status code
 747  */
 748 static efi_status_t EFIAPI
 749 efi_tcg2_get_eventlog(struct efi_tcg2_protocol *this,
 750                       efi_tcg_event_log_format log_format,
 751                       u64 *event_log_location, u64 *event_log_last_entry,
 752                       bool *event_log_truncated)
 753 {
 754         efi_status_t ret = EFI_SUCCESS;
 755         struct udevice *dev;
 756
 757         EFI_ENTRY("%p, %u, %p, %p,  %p", this, log_format, event_log_location,
 758                   event_log_last_entry, event_log_truncated);
 759
 760         if (!this || !event_log_location || !event_log_last_entry ||
 761             !event_log_truncated) {
 762                 ret = EFI_INVALID_PARAMETER;
 763                 goto out;
 764         }
 765
 766         /* Only support TPMV2 */
 767         if (log_format != TCG2_EVENT_LOG_FORMAT_TCG_2) {
 768                 ret = EFI_INVALID_PARAMETER;
 769                 goto out;
 770         }
 771
 772         ret = platform_get_tpm2_device(&dev);
 773         if (ret != EFI_SUCCESS) {
 774                 event_log_location = NULL;
 775                 event_log_last_entry = NULL;
 776                 *event_log_truncated = false;
 777                 ret = EFI_SUCCESS;
 778                 goto out;
 779         }
 780         *event_log_location = (uintptr_t)event_log.buffer;
 781         *event_log_last_entry = (uintptr_t)(event_log.buffer + event_log.pos -
 782                                             event_log.last_event_size);
 783         *event_log_truncated = event_log.truncated;
 784         event_log.get_event_called = true;
 785
 786 out:
 787         return EFI_EXIT(ret);
 788 }
 789
 790 /**
 791  * tcg2_hash_pe_image() - calculate PE/COFF image hash
 792  *
 793  * @efi:                pointer to the EFI binary
 794  * @efi_size:           size of @efi binary
 795  * @digest_list:        list of digest algorithms to extend
 796  *
 797  * Return:      status code
 798  */
 799 static efi_status_t tcg2_hash_pe_image(void *efi, u64 efi_size,
 800                                        struct tpml_digest_values *digest_list)
 801 {
 802         WIN_CERTIFICATE *wincerts = NULL;
 803         size_t wincerts_len;
 804         struct efi_image_regions *regs = NULL;
 805         void *new_efi = NULL;
 806         u8 hash[TPM2_SHA512_DIGEST_SIZE];
 807         efi_status_t ret;
 808         u32 active;
 809         int i;
 810
 811         new_efi = efi_prepare_aligned_image(efi, &efi_size);
 812         if (!new_efi)
 813                 return EFI_OUT_OF_RESOURCES;
 814
 815         if (!efi_image_parse(new_efi, efi_size, &regs, &wincerts,
 816                              &wincerts_len)) {
 817                 log_err("Parsing PE executable image failed\n");
 818                 ret = EFI_UNSUPPORTED;
 819                 goto out;
 820         }
 821
 822         ret = __get_active_pcr_banks(&active);
 823         if (ret != EFI_SUCCESS) {
 824                 goto out;
 825         }
 826
 827         digest_list->count = 0;
 828         for (i = 0; i < MAX_HASH_COUNT; i++) {
 829                 u16 hash_alg = hash_algo_list[i].hash_alg;
 830
 831                 if (!(active & alg_to_mask(hash_alg)))
 832                         continue;
 833                 switch (hash_alg) {
 834                 case TPM2_ALG_SHA1:
 835                         hash_calculate("sha1", regs->reg, regs->num, hash);
 836                         break;
 837                 case TPM2_ALG_SHA256:
 838                         hash_calculate("sha256", regs->reg, regs->num, hash);
 839                         break;
 840                 case TPM2_ALG_SHA384:
 841                         hash_calculate("sha384", regs->reg, regs->num, hash);
 842                         break;
 843                 case TPM2_ALG_SHA512:
 844                         hash_calculate("sha512", regs->reg, regs->num, hash);
 845                         break;
 846                 default:
 847                         EFI_PRINT("Unsupported algorithm %x\n", hash_alg);
 848                         return EFI_INVALID_PARAMETER;
 849                 }
 850                 digest_list->digests[digest_list->count].hash_alg = hash_alg;
 851                 memcpy(&digest_list->digests[digest_list->count].digest, hash,
 852                        (u32)alg_to_len(hash_alg));
 853                 digest_list->count++;
 854         }
 855
 856 out:
 857         if (new_efi != efi)
 858                 free(new_efi);
 859         free(regs);
 860
 861         return ret;
 862 }
 863
 864 /**
 865  * tcg2_measure_pe_image() - measure PE/COFF image
 866  *
 867  * @efi:                pointer to the EFI binary
 868  * @efi_size:           size of @efi binary
 869  * @handle:             loaded image handle
 870  * @loaded_image:       loaded image protocol
 871  *
 872  * Return:      status code
 873  */
 874 efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size,
 875                                    struct efi_loaded_image_obj *handle,
 876                                    struct efi_loaded_image *loaded_image)
 877 {
 878         struct tpml_digest_values digest_list;
 879         efi_status_t ret;
 880         struct udevice *dev;
 881         u32 pcr_index, event_type, event_size;
 882         struct uefi_image_load_event *image_load_event;
 883         struct efi_device_path *device_path;
 884         u32 device_path_length;
 885         IMAGE_DOS_HEADER *dos;
 886         IMAGE_NT_HEADERS32 *nt;
 887         struct efi_handler *handler;
 888
 889         ret = platform_get_tpm2_device(&dev);
 890         if (ret != EFI_SUCCESS)
 891                 return ret;
 892
 893         switch (handle->image_type) {
 894         case IMAGE_SUBSYSTEM_EFI_APPLICATION:
 895                 pcr_index = 4;
 896                 event_type = EV_EFI_BOOT_SERVICES_APPLICATION;
 897                 break;
 898         case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
 899                 pcr_index = 2;
 900                 event_type = EV_EFI_BOOT_SERVICES_DRIVER;
 901                 break;
 902         case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
 903                 pcr_index = 2;
 904                 event_type = EV_EFI_RUNTIME_SERVICES_DRIVER;
 905                 break;
 906         default:
 907                 return EFI_UNSUPPORTED;
 908         }
 909
 910         ret = tcg2_hash_pe_image(efi, efi_size, &digest_list);
 911         if (ret != EFI_SUCCESS)
 912                 return ret;
 913
 914         ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
 915         if (ret != EFI_SUCCESS)
 916                 return ret;
 917
 918         ret = efi_search_protocol(&handle->header,
 919                                   &efi_guid_loaded_image_device_path, &handler);
 920         if (ret != EFI_SUCCESS)
 921                 return ret;
 922
 923         device_path = handler->protocol_interface;
 924         device_path_length = efi_dp_size(device_path);
 925         if (device_path_length > 0) {
 926                 /* add end node size */
 927                 device_path_length += sizeof(struct efi_device_path);
 928         }
 929         event_size = sizeof(struct uefi_image_load_event) + device_path_length;
 930         image_load_event = calloc(1, event_size);
 931         if (!image_load_event)
 932                 return EFI_OUT_OF_RESOURCES;
 933
 934         image_load_event->image_location_in_memory = (uintptr_t)efi;
 935         image_load_event->image_length_in_memory = efi_size;
 936         image_load_event->length_of_device_path = device_path_length;
 937
 938         dos = (IMAGE_DOS_HEADER *)efi;
 939         nt = (IMAGE_NT_HEADERS32 *)(efi + dos->e_lfanew);
 940         if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 941                 IMAGE_NT_HEADERS64 *nt64 = (IMAGE_NT_HEADERS64 *)nt;
 942
 943                 image_load_event->image_link_time_address =
 944                                 nt64->OptionalHeader.ImageBase;
 945         } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 946                 image_load_event->image_link_time_address =
 947                                 nt->OptionalHeader.ImageBase;
 948         } else {
 949                 ret = EFI_INVALID_PARAMETER;
 950                 goto out;
 951         }
 952
 953         /* device_path_length might be zero */
 954         memcpy(image_load_event->device_path, device_path, device_path_length);
 955
 956         ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
 957                                     event_size, (u8 *)image_load_event);
 958
 959 out:
 960         free(image_load_event);
 961
 962         return ret;
 963 }
 964
 965 /**
 966  * efi_tcg2_hash_log_extend_event() - extend and optionally log events
 967  *
 968  * @this:                       TCG2 protocol instance
 969  * @flags:                      bitmap providing additional information on the
 970  *                              operation
 971  * @data_to_hash:               physical address of the start of the data buffer
 972  *                              to be hashed
 973  * @data_to_hash_len:           the length in bytes of the buffer referenced by
 974  *                              data_to_hash
 975  * @efi_tcg_event:              pointer to data buffer containing information
 976  *                              about the event
 977  *
 978  * Return:      status code
 979  */
 980 static efi_status_t EFIAPI
 981 efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags,
 982                                u64 data_to_hash, u64 data_to_hash_len,
 983                                struct efi_tcg2_event *efi_tcg_event)
 984 {
 985         struct udevice *dev;
 986         efi_status_t ret;
 987         u32 event_type, pcr_index, event_size;
 988         struct tpml_digest_values digest_list;
 989
 990         EFI_ENTRY("%p, %llu, %llu, %llu, %p", this, flags, data_to_hash,
 991                   data_to_hash_len, efi_tcg_event);
 992
 993         if (!this || !data_to_hash || !efi_tcg_event) {
 994                 ret = EFI_INVALID_PARAMETER;
 995                 goto out;
 996         }
 997
 998         ret = platform_get_tpm2_device(&dev);
 999         if (ret != EFI_SUCCESS)
1000                 goto out;
1001
1002         if (efi_tcg_event->size < efi_tcg_event->header.header_size +
1003             sizeof(u32)) {
1004                 ret = EFI_INVALID_PARAMETER;
1005                 goto out;
1006         }
1007
1008         if (efi_tcg_event->header.pcr_index > EFI_TCG2_MAX_PCR_INDEX) {
1009                 ret = EFI_INVALID_PARAMETER;
1010                 goto out;
1011         }
1012
1013         /*
1014          * if PE_COFF_IMAGE is set we need to make sure the image is not
1015          * corrupted, verify it and hash the PE/COFF image in accordance with
1016          * the procedure specified in "Calculating the PE Image Hash"
1017          * section of the "Windows Authenticode Portable Executable Signature
1018          * Format"
1019          */
1020         if (flags & PE_COFF_IMAGE) {
1021                 IMAGE_NT_HEADERS32 *nt;
1022
1023                 ret = efi_check_pe((void *)(uintptr_t)data_to_hash,
1024                                    data_to_hash_len, (void **)&nt);
1025                 if (ret != EFI_SUCCESS) {
1026                         log_err("Not a valid PE-COFF file\n");
1027                         ret = EFI_UNSUPPORTED;
1028                         goto out;
1029                 }
1030                 ret = tcg2_hash_pe_image((void *)(uintptr_t)data_to_hash,
1031                                          data_to_hash_len, &digest_list);
1032         } else {
1033                 ret = tcg2_create_digest((u8 *)(uintptr_t)data_to_hash,
1034                                          data_to_hash_len, &digest_list);
1035         }
1036
1037         if (ret != EFI_SUCCESS)
1038                 goto out;
1039
1040         pcr_index = efi_tcg_event->header.pcr_index;
1041         event_type = efi_tcg_event->header.event_type;
1042
1043         ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
1044         if (ret != EFI_SUCCESS)
1045                 goto out;
1046
1047         if (flags & EFI_TCG2_EXTEND_ONLY) {
1048                 if (event_log.truncated)
1049                         ret = EFI_VOLUME_FULL;
1050                 goto out;
1051         }
1052
1053         /*
1054          * The efi_tcg_event size includes the size component and the
1055          * headersize
1056          */
1057         event_size = efi_tcg_event->size - sizeof(efi_tcg_event->size) -
1058                 efi_tcg_event->header.header_size;
1059         ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
1060                                     event_size, efi_tcg_event->event);
1061 out:
1062         return EFI_EXIT(ret);
1063 }
1064
1065 /**
1066  * efi_tcg2_submit_command() - Send command to the TPM
1067  *
1068  * @this:                       TCG2 protocol instance
1069  * @input_param_block_size:     size of the TPM input parameter block
1070  * @input_param_block:          pointer to the TPM input parameter block
1071  * @output_param_block_size:    size of the TPM output parameter block
1072  * @output_param_block:         pointer to the TPM output parameter block
1073  *
1074  * Return:      status code
1075  */
1076 static efi_status_t EFIAPI
1077 efi_tcg2_submit_command(struct efi_tcg2_protocol *this,
1078                         u32 input_param_block_size,
1079                         u8 *input_param_block,
1080                         u32 output_param_block_size,
1081                         u8 *output_param_block)
1082 {
1083         struct udevice *dev;
1084         efi_status_t ret;
1085         u32 rc;
1086         size_t resp_buf_size = output_param_block_size;
1087
1088         EFI_ENTRY("%p, %u, %p, %u, %p", this, input_param_block_size,
1089                   input_param_block, output_param_block_size, output_param_block);
1090
1091         if (!this || !input_param_block || !input_param_block_size) {
1092                 ret = EFI_INVALID_PARAMETER;
1093                 goto out;
1094         }
1095
1096         ret = platform_get_tpm2_device(&dev);
1097         if (ret != EFI_SUCCESS)
1098                 goto out;
1099
1100         rc = tpm2_submit_command(dev, input_param_block,
1101                                  output_param_block, &resp_buf_size);
1102         if (rc) {
1103                 ret = (rc == -ENOSPC) ? EFI_OUT_OF_RESOURCES : EFI_DEVICE_ERROR;
1104
1105                 goto out;
1106         }
1107
1108 out:
1109         return EFI_EXIT(ret);
1110 }
1111
1112 /**
1113  * efi_tcg2_get_active_pcr_banks() - returns the currently active PCR banks
1114  *
1115  * @this:                       TCG2 protocol instance
1116  * @active_pcr_banks:           pointer for receiving the bitmap of currently
1117  *                              active PCR banks
1118  *
1119  * Return:      status code
1120  */
1121 static efi_status_t EFIAPI
1122 efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this,
1123                               u32 *active_pcr_banks)
1124 {
1125         efi_status_t ret;
1126
1127         if (!this || !active_pcr_banks) {
1128                 ret = EFI_INVALID_PARAMETER;
1129                 goto out;
1130         }
1131
1132         EFI_ENTRY("%p, %p", this, active_pcr_banks);
1133         ret = __get_active_pcr_banks(active_pcr_banks);
1134
1135 out:
1136         return EFI_EXIT(ret);
1137 }
1138
1139 /**
1140  * efi_tcg2_set_active_pcr_banks() - sets the currently active PCR banks
1141  *
1142  * @this:                       TCG2 protocol instance
1143  * @active_pcr_banks:           bitmap of the requested active PCR banks
1144  *
1145  * Return:      status code
1146  */
1147 static efi_status_t EFIAPI
1148 efi_tcg2_set_active_pcr_banks(__maybe_unused struct efi_tcg2_protocol *this,
1149                               u32 __maybe_unused active_pcr_banks)
1150 {
1151         return EFI_UNSUPPORTED;
1152 }
1153
1154 /**
1155  * efi_tcg2_get_result_of_set_active_pcr_banks() - retrieve result for previous
1156  *                                                 set_active_pcr_banks()
1157  *
1158  * @this:                       TCG2 protocol instance
1159  * @operation_present:          non-zero value to indicate a
1160  *                              set_active_pcr_banks operation was
1161  *                              invoked during last boot
1162  * @response:                   result value could be returned
1163  *
1164  * Return:      status code
1165  */
1166 static efi_status_t EFIAPI
1167 efi_tcg2_get_result_of_set_active_pcr_banks(__maybe_unused struct efi_tcg2_protocol *this,
1168                                             u32 __maybe_unused *operation_present,
1169                                             u32 __maybe_unused *response)
1170 {
1171         return EFI_UNSUPPORTED;
1172 }
1173
1174 static const struct efi_tcg2_protocol efi_tcg2_protocol = {
1175         .get_capability = efi_tcg2_get_capability,
1176         .get_eventlog = efi_tcg2_get_eventlog,
1177         .hash_log_extend_event = efi_tcg2_hash_log_extend_event,
1178         .submit_command = efi_tcg2_submit_command,
1179         .get_active_pcr_banks = efi_tcg2_get_active_pcr_banks,
1180         .set_active_pcr_banks = efi_tcg2_set_active_pcr_banks,
1181         .get_result_of_set_active_pcr_banks = efi_tcg2_get_result_of_set_active_pcr_banks,
1182 };
1183
1184 /**
1185  * create_specid_event() - Create the first event in the eventlog
1186  *
1187  * @dev:                        tpm device
1188  * @event_header:               Pointer to the final event header
1189  * @event_size:                 final spec event size
1190  *
1191  * Return:      status code
1192  */
1193 static efi_status_t create_specid_event(struct udevice *dev, void *buffer,
1194                                         size_t *event_size)
1195 {
1196         struct tcg_efi_spec_id_event *spec_event;
1197         size_t spec_event_size;
1198         efi_status_t ret = EFI_DEVICE_ERROR;
1199         u32 active = 0, supported = 0, pcr_count = 0, alg_count = 0;
1200         int err;
1201         size_t i;
1202
1203         /*
1204          * Create Spec event. This needs to be the first event in the log
1205          * according to the TCG EFI protocol spec
1206          */
1207
1208         /* Setup specID event data */
1209         spec_event = (struct tcg_efi_spec_id_event *)buffer;
1210         memcpy(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03,
1211                sizeof(spec_event->signature));
1212         put_unaligned_le32(0, &spec_event->platform_class); /* type client */
1213         spec_event->spec_version_minor =
1214                 TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2;
1215         spec_event->spec_version_major =
1216                 TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2;
1217         spec_event->spec_errata =
1218                 TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2;
1219         spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32);
1220
1221         err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_count);
1222
1223         if (err)
1224                 goto out;
1225
1226         for (i = 0; i < pcr_count; i++) {
1227                 u16 hash_alg = hash_algo_list[i].hash_alg;
1228                 u16 hash_len = hash_algo_list[i].hash_len;
1229
1230                 if (active & alg_to_mask(hash_alg)) {
1231                         put_unaligned_le16(hash_alg,
1232                                            &spec_event->digest_sizes[alg_count].algorithm_id);
1233                         put_unaligned_le16(hash_len,
1234                                            &spec_event->digest_sizes[alg_count].digest_size);
1235                         alg_count++;
1236                 }
1237         }
1238
1239         spec_event->number_of_algorithms = alg_count;
1240         if (spec_event->number_of_algorithms > MAX_HASH_COUNT ||
1241             spec_event->number_of_algorithms < 1)
1242                 goto out;
1243
1244         /*
1245          * the size of the spec event and placement of vendor_info_size
1246          * depends on supported algoriths
1247          */
1248         spec_event_size =
1249                 offsetof(struct tcg_efi_spec_id_event, digest_sizes) +
1250                 spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]);
1251         /* no vendor info for us */
1252         memset(buffer + spec_event_size, 0, 1);
1253         /* add a byte for vendor_info_size in the spec event */
1254         spec_event_size += 1;
1255         *event_size = spec_event_size;
1256
1257         return EFI_SUCCESS;
1258
1259 out:
1260         return ret;
1261 }
1262
1263 /**
1264  * tcg2_uninit - remove the final event table and free efi memory on failures
1265  */
1266 void tcg2_uninit(void)
1267 {
1268         efi_status_t ret;
1269
1270         ret = efi_install_configuration_table(&efi_guid_final_events, NULL);
1271         if (ret != EFI_SUCCESS)
1272                 log_err("Failed to delete final events config table\n");
1273
1274         efi_free_pool(event_log.buffer);
1275         event_log.buffer = NULL;
1276         efi_free_pool(event_log.final_buffer);
1277         event_log.final_buffer = NULL;
1278 }
1279
1280 /**
1281  * create_final_event() - Create the final event and install the config
1282  *                      defined by the TCG EFI spec
1283  */
1284 static efi_status_t create_final_event(void)
1285 {
1286         struct efi_tcg2_final_events_table *final_event;
1287         efi_status_t ret;
1288
1289         /*
1290          * All events generated after the invocation of
1291          * EFI_TCG2_GET_EVENT_LOGS need to be stored in an instance of an
1292          * EFI_CONFIGURATION_TABLE
1293          */
1294         ret = efi_allocate_pool(EFI_ACPI_MEMORY_NVS, TPM2_EVENT_LOG_SIZE,
1295                                 &event_log.final_buffer);
1296         if (ret != EFI_SUCCESS)
1297                 goto out;
1298
1299         memset(event_log.final_buffer, 0xff, TPM2_EVENT_LOG_SIZE);
1300         final_event = event_log.final_buffer;
1301         final_event->number_of_events = 0;
1302         final_event->version = EFI_TCG2_FINAL_EVENTS_TABLE_VERSION;
1303         event_log.final_pos = sizeof(*final_event);
1304         ret = efi_install_configuration_table(&efi_guid_final_events,
1305                                               final_event);
1306         if (ret != EFI_SUCCESS) {
1307                 efi_free_pool(event_log.final_buffer);
1308                 event_log.final_buffer = NULL;
1309         }
1310
1311 out:
1312         return ret;
1313 }
1314
1315 /**
1316  * efi_init_event_log() - initialize an eventlog
1317  */
1318 static efi_status_t efi_init_event_log(void)
1319 {
1320         /*
1321          * vendor_info_size is currently set to 0, we need to change the length
1322          * and allocate the flexible array member if this changes
1323          */
1324         struct tcg_pcr_event *event_header = NULL;
1325         struct udevice *dev;
1326         size_t spec_event_size;
1327         efi_status_t ret;
1328
1329         ret = platform_get_tpm2_device(&dev);
1330         if (ret != EFI_SUCCESS)
1331                 goto out;
1332
1333         ret = efi_allocate_pool(EFI_BOOT_SERVICES_DATA, TPM2_EVENT_LOG_SIZE,
1334                                 (void **)&event_log.buffer);
1335         if (ret != EFI_SUCCESS)
1336                 goto out;
1337
1338         /*
1339          * initialize log area as 0xff so the OS can easily figure out the
1340          * last log entry
1341          */
1342         memset(event_log.buffer, 0xff, TPM2_EVENT_LOG_SIZE);
1343         event_log.pos = 0;
1344         event_log.last_event_size = 0;
1345         event_log.get_event_called = false;
1346         event_log.ebs_called = false;
1347         event_log.truncated = false;
1348
1349         /*
1350          * The log header is defined to be in SHA1 event log entry format.
1351          * Setup event header
1352          */
1353         event_header =  (struct tcg_pcr_event *)event_log.buffer;
1354         put_unaligned_le32(0, &event_header->pcr_index);
1355         put_unaligned_le32(EV_NO_ACTION, &event_header->event_type);
1356         memset(&event_header->digest, 0, sizeof(event_header->digest));
1357         ret = create_specid_event(dev, (void *)((uintptr_t)event_log.buffer + sizeof(*event_header)),
1358                                   &spec_event_size);
1359         if (ret != EFI_SUCCESS)
1360                 goto free_pool;
1361         put_unaligned_le32(spec_event_size, &event_header->event_size);
1362         event_log.pos = spec_event_size + sizeof(*event_header);
1363         event_log.last_event_size = event_log.pos;
1364
1365         ret = create_final_event();
1366         if (ret != EFI_SUCCESS)
1367                 goto free_pool;
1368
1369 out:
1370         return ret;
1371
1372 free_pool:
1373         efi_free_pool(event_log.buffer);
1374         event_log.buffer = NULL;
1375         return ret;
1376 }
1377
1378 /**
1379  * tcg2_measure_event() - common function to add event log and extend PCR
1380  *
1381  * @dev:                TPM device
1382  * @pcr_index:          PCR index
1383  * @event_type:         type of event added
1384  * @size:               event size
1385  * @event:              event data
1386  *
1387  * Return:      status code
1388  */
1389 static efi_status_t
1390 tcg2_measure_event(struct udevice *dev, u32 pcr_index, u32 event_type,
1391                    u32 size, u8 event[])
1392 {
1393         struct tpml_digest_values digest_list;
1394         efi_status_t ret;
1395
1396         ret = tcg2_create_digest(event, size, &digest_list);
1397         if (ret != EFI_SUCCESS)
1398                 goto out;
1399
1400         ret = tcg2_pcr_extend(dev, pcr_index, &digest_list);
1401         if (ret != EFI_SUCCESS)
1402                 goto out;
1403
1404         ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list,
1405                                     size, event);
1406
1407 out:
1408         return ret;
1409 }
1410
1411 /**
1412  * efi_append_scrtm_version - Append an S-CRTM EV_S_CRTM_VERSION event on the
1413  *                            eventlog and extend the PCRs
1414  *
1415  * @dev:        TPM device
1416  *
1417  * @Return:     status code
1418  */
1419 static efi_status_t efi_append_scrtm_version(struct udevice *dev)
1420 {
1421         efi_status_t ret;
1422
1423         ret = tcg2_measure_event(dev, 0, EV_S_CRTM_VERSION,
1424                                  strlen(version_string) + 1,
1425                                  (u8 *)version_string);
1426
1427         return ret;
1428 }
1429
1430 /**
1431  * tcg2_measure_variable() - add variable event log and extend PCR
1432  *
1433  * @dev:                TPM device
1434  * @pcr_index:          PCR index
1435  * @event_type:         type of event added
1436  * @var_name:           variable name
1437  * @guid:               guid
1438  * @data_size:          variable data size
1439  * @data:               variable data
1440  *
1441  * Return:      status code
1442  */
1443 static efi_status_t tcg2_measure_variable(struct udevice *dev, u32 pcr_index,
1444                                           u32 event_type, const u16 *var_name,
1445                                           const efi_guid_t *guid,
1446                                           efi_uintn_t data_size, u8 *data)
1447 {
1448         u32 event_size;
1449         efi_status_t ret;
1450         struct efi_tcg2_uefi_variable_data *event;
1451
1452         event_size = sizeof(event->variable_name) +
1453                      sizeof(event->unicode_name_length) +
1454                      sizeof(event->variable_data_length) +
1455                      (u16_strlen(var_name) * sizeof(u16)) + data_size;
1456         event = malloc(event_size);
1457         if (!event)
1458                 return EFI_OUT_OF_RESOURCES;
1459
1460         guidcpy(&event->variable_name, guid);
1461         event->unicode_name_length = u16_strlen(var_name);
1462         event->variable_data_length = data_size;
1463         memcpy(event->unicode_name, var_name,
1464                (event->unicode_name_length * sizeof(u16)));
1465         if (data) {
1466                 memcpy((u16 *)event->unicode_name + event->unicode_name_length,
1467                        data, data_size);
1468         }
1469         ret = tcg2_measure_event(dev, pcr_index, event_type, event_size,
1470                                  (u8 *)event);
1471         free(event);
1472         return ret;
1473 }
1474
1475 /**
1476  * tcg2_measure_boot_variable() - measure boot variables
1477  *
1478  * @dev:        TPM device
1479  *
1480  * Return:      status code
1481  */
1482 static efi_status_t tcg2_measure_boot_variable(struct udevice *dev)
1483 {
1484         u16 *boot_order;
1485         u16 *boot_index;
1486         u16 var_name[] = L"BootOrder";
1487         u16 boot_name[] = L"Boot####";
1488         u8 *bootvar;
1489         efi_uintn_t var_data_size;
1490         u32 count, i;
1491         efi_status_t ret;
1492
1493         boot_order = efi_get_var(var_name, &efi_global_variable_guid,
1494                                  &var_data_size);
1495         if (!boot_order) {
1496                 /* If "BootOrder" is not defined, skip the boot variable measurement */
1497                 return EFI_SUCCESS;
1498         }
1499
1500         ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2, var_name,
1501                                     &efi_global_variable_guid, var_data_size,
1502                                     (u8 *)boot_order);
1503         if (ret != EFI_SUCCESS)
1504                 goto error;
1505
1506         count = var_data_size / sizeof(*boot_order);
1507         boot_index = boot_order;
1508         for (i = 0; i < count; i++) {
1509                 efi_create_indexed_name(boot_name, sizeof(boot_name),
1510                                         "Boot", *boot_index++);
1511
1512                 bootvar = efi_get_var(boot_name, &efi_global_variable_guid,
1513                                       &var_data_size);
1514
1515                 if (!bootvar) {
1516                         log_debug("%ls not found\n", boot_name);
1517                         continue;
1518                 }
1519
1520                 ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2,
1521                                             boot_name,
1522                                             &efi_global_variable_guid,
1523                                             var_data_size, bootvar);
1524                 free(bootvar);
1525                 if (ret != EFI_SUCCESS)
1526                         goto error;
1527         }
1528
1529 error:
1530         free(boot_order);
1531         return ret;
1532 }
1533
1534 /**
1535  * tcg2_measure_smbios() - measure smbios table
1536  *
1537  * @dev:        TPM device
1538  * @entry:      pointer to the smbios_entry structure
1539  *
1540  * Return:      status code
1541  */
1542 static efi_status_t
1543 tcg2_measure_smbios(struct udevice *dev,
1544                     const struct smbios_entry *entry)
1545 {
1546         efi_status_t ret;
1547         struct smbios_header *smbios_copy;
1548         struct smbios_handoff_table_pointers2 *event = NULL;
1549         u32 event_size;
1550
1551         /*
1552          * TCG PC Client PFP Spec says
1553          * "SMBIOS structures that contain static configuration information
1554          * (e.g. Platform Manufacturer Enterprise Number assigned by IANA,
1555          * platform model number, Vendor and Device IDs for each SMBIOS table)
1556          * that is relevant to the security of the platform MUST be measured".
1557          * Device dependent parameters such as serial number are cleared to
1558          * zero or spaces for the measurement.
1559          */
1560         event_size = sizeof(struct smbios_handoff_table_pointers2) +
1561                      FIELD_SIZEOF(struct efi_configuration_table, guid) +
1562                      entry->struct_table_length;
1563         event = calloc(1, event_size);
1564         if (!event) {
1565                 ret = EFI_OUT_OF_RESOURCES;
1566                 goto out;
1567         }
1568
1569         event->table_description_size = sizeof(SMBIOS_HANDOFF_TABLE_DESC);
1570         memcpy(event->table_description, SMBIOS_HANDOFF_TABLE_DESC,
1571                sizeof(SMBIOS_HANDOFF_TABLE_DESC));
1572         put_unaligned_le64(1, &event->number_of_tables);
1573         guidcpy(&event->table_entry[0].guid, &smbios_guid);
1574         smbios_copy = (struct smbios_header *)((uintptr_t)&event->table_entry[0].table);
1575         memcpy(&event->table_entry[0].table,
1576                (void *)((uintptr_t)entry->struct_table_address),
1577                entry->struct_table_length);
1578
1579         smbios_prepare_measurement(entry, smbios_copy);
1580
1581         ret = tcg2_measure_event(dev, 1, EV_EFI_HANDOFF_TABLES2, event_size,
1582                                  (u8 *)event);
1583         if (ret != EFI_SUCCESS)
1584                 goto out;
1585
1586 out:
1587         free(event);
1588
1589         return ret;
1590 }
1591
1592 /**
1593  * find_smbios_table() - find smbios table
1594  *
1595  * Return:      pointer to the smbios table
1596  */
1597 static void *find_smbios_table(void)
1598 {
1599         u32 i;
1600
1601         for (i = 0; i < systab.nr_tables; i++) {
1602                 if (!guidcmp(&smbios_guid, &systab.tables[i].guid))
1603                         return systab.tables[i].table;
1604         }
1605
1606         return NULL;
1607 }
1608
1609 /**
1610  * tcg2_measure_gpt_table() - measure gpt table
1611  *
1612  * @dev:                TPM device
1613  * @loaded_image:       handle to the loaded image
1614  *
1615  * Return:      status code
1616  */
1617 static efi_status_t
1618 tcg2_measure_gpt_data(struct udevice *dev,
1619                       struct efi_loaded_image_obj *loaded_image)
1620 {
1621         efi_status_t ret;
1622         efi_handle_t handle;
1623         struct efi_handler *dp_handler;
1624         struct efi_device_path *orig_device_path;
1625         struct efi_device_path *device_path;
1626         struct efi_device_path *dp;
1627         struct efi_block_io *block_io;
1628         struct efi_gpt_data *event = NULL;
1629         efi_guid_t null_guid = NULL_GUID;
1630         gpt_header *gpt_h;
1631         gpt_entry *entry = NULL;
1632         gpt_entry *gpt_e;
1633         u32 num_of_valid_entry = 0;
1634         u32 event_size;
1635         u32 i;
1636         u32 total_gpt_entry_size;
1637
1638         ret = efi_search_protocol(&loaded_image->header,
1639                                   &efi_guid_loaded_image_device_path,
1640                                   &dp_handler);
1641         if (ret != EFI_SUCCESS)
1642                 return ret;
1643
1644         orig_device_path = dp_handler->protocol_interface;
1645         if (!orig_device_path) /* no device path, skip GPT measurement */
1646                 return EFI_SUCCESS;
1647
1648         device_path = efi_dp_dup(orig_device_path);
1649         if (!device_path)
1650                 return EFI_OUT_OF_RESOURCES;
1651
1652         dp = search_gpt_dp_node(device_path);
1653         if (!dp) {
1654                 /* no GPT device path node found, skip GPT measurement */
1655                 ret = EFI_SUCCESS;
1656                 goto out1;
1657         }
1658
1659         /* read GPT header */
1660         dp->type = DEVICE_PATH_TYPE_END;
1661         dp->sub_type = DEVICE_PATH_SUB_TYPE_END;
1662         dp = device_path;
1663         ret = EFI_CALL(systab.boottime->locate_device_path(&efi_block_io_guid,
1664                                                            &dp, &handle));
1665         if (ret != EFI_SUCCESS)
1666                 goto out1;
1667
1668         ret = EFI_CALL(efi_handle_protocol(handle,
1669                                            &efi_block_io_guid, (void **)&block_io));
1670         if (ret != EFI_SUCCESS)
1671                 goto out1;
1672
1673         gpt_h = memalign(block_io->media->io_align, block_io->media->block_size);
1674         if (!gpt_h) {
1675                 ret = EFI_OUT_OF_RESOURCES;
1676                 goto out2;
1677         }
1678
1679         ret = block_io->read_blocks(block_io, block_io->media->media_id, 1,
1680                                     block_io->media->block_size, gpt_h);
1681         if (ret != EFI_SUCCESS)
1682                 goto out2;
1683
1684         /* read GPT entry */
1685         total_gpt_entry_size = gpt_h->num_partition_entries *
1686                                gpt_h->sizeof_partition_entry;
1687         entry = memalign(block_io->media->io_align, total_gpt_entry_size);
1688         if (!entry) {
1689                 ret = EFI_OUT_OF_RESOURCES;
1690                 goto out2;
1691         }
1692
1693         ret = block_io->read_blocks(block_io, block_io->media->media_id,
1694                                     gpt_h->partition_entry_lba,
1695                                     total_gpt_entry_size, entry);
1696         if (ret != EFI_SUCCESS)
1697                 goto out2;
1698
1699         /* count valid GPT entry */
1700         gpt_e = entry;
1701         for (i = 0; i < gpt_h->num_partition_entries; i++) {
1702                 if (guidcmp(&null_guid, &gpt_e->partition_type_guid))
1703                         num_of_valid_entry++;
1704
1705                 gpt_e = (gpt_entry *)((u8 *)gpt_e + gpt_h->sizeof_partition_entry);
1706         }
1707
1708         /* prepare event data for measurement */
1709         event_size = sizeof(struct efi_gpt_data) +
1710                 (num_of_valid_entry * gpt_h->sizeof_partition_entry);
1711         event = calloc(1, event_size);
1712         if (!event) {
1713                 ret = EFI_OUT_OF_RESOURCES;
1714                 goto out2;
1715         }
1716         memcpy(event, gpt_h, sizeof(gpt_header));
1717         put_unaligned_le64(num_of_valid_entry, &event->number_of_partitions);
1718
1719         /* copy valid GPT entry */
1720         gpt_e = entry;
1721         num_of_valid_entry = 0;
1722         for (i = 0; i < gpt_h->num_partition_entries; i++) {
1723                 if (guidcmp(&null_guid, &gpt_e->partition_type_guid)) {
1724                         memcpy((u8 *)event->partitions +
1725                                (num_of_valid_entry * gpt_h->sizeof_partition_entry),
1726                                gpt_e, gpt_h->sizeof_partition_entry);
1727                         num_of_valid_entry++;
1728                 }
1729
1730                 gpt_e = (gpt_entry *)((u8 *)gpt_e + gpt_h->sizeof_partition_entry);
1731         }
1732
1733         ret = tcg2_measure_event(dev, 5, EV_EFI_GPT_EVENT, event_size, (u8 *)event);
1734         if (ret != EFI_SUCCESS)
1735                 goto out2;
1736
1737 out2:
1738         EFI_CALL(efi_close_protocol((efi_handle_t)block_io, &efi_block_io_guid,
1739                                     NULL, NULL));
1740         free(gpt_h);
1741         free(entry);
1742         free(event);
1743 out1:
1744         efi_free_pool(device_path);
1745
1746         return ret;
1747 }
1748
1749 /**
1750  * efi_tcg2_measure_efi_app_invocation() - measure efi app invocation
1751  *
1752  * Return:      status code
1753  */
1754 efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *handle)
1755 {
1756         efi_status_t ret;
1757         u32 pcr_index;
1758         struct udevice *dev;
1759         u32 event = 0;
1760         struct smbios_entry *entry;
1761
1762         if (tcg2_efi_app_invoked)
1763                 return EFI_SUCCESS;
1764
1765         ret = platform_get_tpm2_device(&dev);
1766         if (ret != EFI_SUCCESS)
1767                 return ret;
1768
1769         ret = tcg2_measure_boot_variable(dev);
1770         if (ret != EFI_SUCCESS)
1771                 goto out;
1772
1773         ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
1774                                  strlen(EFI_CALLING_EFI_APPLICATION),
1775                                  (u8 *)EFI_CALLING_EFI_APPLICATION);
1776         if (ret != EFI_SUCCESS)
1777                 goto out;
1778
1779         entry = (struct smbios_entry *)find_smbios_table();
1780         if (entry) {
1781                 ret = tcg2_measure_smbios(dev, entry);
1782                 if (ret != EFI_SUCCESS)
1783                         goto out;
1784         }
1785
1786         ret = tcg2_measure_gpt_data(dev, handle);
1787         if (ret != EFI_SUCCESS)
1788                 goto out;
1789
1790         for (pcr_index = 0; pcr_index <= 7; pcr_index++) {
1791                 ret = tcg2_measure_event(dev, pcr_index, EV_SEPARATOR,
1792                                          sizeof(event), (u8 *)&event);
1793                 if (ret != EFI_SUCCESS)
1794                         goto out;
1795         }
1796
1797         tcg2_efi_app_invoked = true;
1798 out:
1799         return ret;
1800 }
1801
1802 /**
1803  * efi_tcg2_measure_efi_app_exit() - measure efi app exit
1804  *
1805  * Return:      status code
1806  */
1807 efi_status_t efi_tcg2_measure_efi_app_exit(void)
1808 {
1809         efi_status_t ret;
1810         struct udevice *dev;
1811
1812         ret = platform_get_tpm2_device(&dev);
1813         if (ret != EFI_SUCCESS)
1814                 return ret;
1815
1816         ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION,
1817                                  strlen(EFI_RETURNING_FROM_EFI_APPLICATION),
1818                                  (u8 *)EFI_RETURNING_FROM_EFI_APPLICATION);
1819         return ret;
1820 }
1821
1822 /**
1823  * efi_tcg2_notify_exit_boot_services() - ExitBootService callback
1824  *
1825  * @event:      callback event
1826  * @context:    callback context
1827  */
1828 static void EFIAPI
1829 efi_tcg2_notify_exit_boot_services(struct efi_event *event, void *context)
1830 {
1831         efi_status_t ret;
1832         struct udevice *dev;
1833
1834         EFI_ENTRY("%p, %p", event, context);
1835
1836         event_log.ebs_called = true;
1837         ret = platform_get_tpm2_device(&dev);
1838         if (ret != EFI_SUCCESS)
1839                 goto out;
1840
1841         ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
1842                                  strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
1843                                  (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
1844         if (ret != EFI_SUCCESS)
1845                 goto out;
1846
1847         ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
1848                                  strlen(EFI_EXIT_BOOT_SERVICES_SUCCEEDED),
1849                                  (u8 *)EFI_EXIT_BOOT_SERVICES_SUCCEEDED);
1850
1851 out:
1852         EFI_EXIT(ret);
1853 }
1854
1855 /**
1856  * efi_tcg2_notify_exit_boot_services_failed()
1857  *  - notify ExitBootServices() is failed
1858  *
1859  * Return:      status code
1860  */
1861 efi_status_t efi_tcg2_notify_exit_boot_services_failed(void)
1862 {
1863         struct udevice *dev;
1864         efi_status_t ret;
1865
1866         ret = platform_get_tpm2_device(&dev);
1867         if (ret != EFI_SUCCESS)
1868                 goto out;
1869
1870         ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
1871                                  strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
1872                                  (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
1873         if (ret != EFI_SUCCESS)
1874                 goto out;
1875
1876         ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
1877                                  strlen(EFI_EXIT_BOOT_SERVICES_FAILED),
1878                                  (u8 *)EFI_EXIT_BOOT_SERVICES_FAILED);
1879
1880 out:
1881         return ret;
1882 }
1883
1884 /**
1885  * tcg2_measure_secure_boot_variable() - measure secure boot variables
1886  *
1887  * @dev:        TPM device
1888  *
1889  * Return:      status code
1890  */
1891 static efi_status_t tcg2_measure_secure_boot_variable(struct udevice *dev)
1892 {
1893         u8 *data;
1894         efi_uintn_t data_size;
1895         u32 count, i;
1896         efi_status_t ret;
1897         u8 deployed_mode;
1898         efi_uintn_t size;
1899         u32 deployed_audit_pcr_index = 1;
1900
1901         size = sizeof(deployed_mode);
1902         ret = efi_get_variable_int(u"DeployedMode", &efi_global_variable_guid,
1903                                    NULL, &size, &deployed_mode, NULL);
1904         if (ret != EFI_SUCCESS || !deployed_mode)
1905                 deployed_audit_pcr_index = 7;
1906
1907         count = ARRAY_SIZE(secure_variables);
1908         for (i = 0; i < count; i++) {
1909                 const efi_guid_t *guid;
1910
1911                 guid = efi_auth_var_get_guid(secure_variables[i].name);
1912
1913                 data = efi_get_var(secure_variables[i].name, guid, &data_size);
1914                 if (!data && !secure_variables[i].accept_empty)
1915                         continue;
1916
1917                 if (u16_strcmp(u"DeployedMode", secure_variables[i].name))
1918                         secure_variables[i].pcr_index = deployed_audit_pcr_index;
1919                 if (u16_strcmp(u"AuditMode", secure_variables[i].name))
1920                         secure_variables[i].pcr_index = deployed_audit_pcr_index;
1921
1922                 ret = tcg2_measure_variable(dev, secure_variables[i].pcr_index,
1923                                             EV_EFI_VARIABLE_DRIVER_CONFIG,
1924                                             secure_variables[i].name, guid,
1925                                             data_size, data);
1926                 free(data);
1927                 if (ret != EFI_SUCCESS)
1928                         goto error;
1929         }
1930
1931 error:
1932         return ret;
1933 }
1934
1935 /**
1936  * efi_tcg2_register() - register EFI_TCG2_PROTOCOL
1937  *
1938  * If a TPM2 device is available, the TPM TCG2 Protocol is registered
1939  *
1940  * Return:      An error status is only returned if adding the protocol fails.
1941  */
1942 efi_status_t efi_tcg2_register(void)
1943 {
1944         efi_status_t ret = EFI_SUCCESS;
1945         struct udevice *dev;
1946         struct efi_event *event;
1947         u32 err;
1948
1949         ret = platform_get_tpm2_device(&dev);
1950         if (ret != EFI_SUCCESS) {
1951                 log_warning("Unable to find TPMv2 device\n");
1952                 return EFI_SUCCESS;
1953         }
1954
1955         /* initialize the TPM as early as possible. */
1956         err = tpm_startup(dev, TPM_ST_CLEAR);
1957         if (err) {
1958                 log_err("TPM startup failed\n");
1959                 goto fail;
1960         }
1961
1962         ret = efi_init_event_log();
1963         if (ret != EFI_SUCCESS)
1964                 goto fail;
1965
1966         ret = efi_append_scrtm_version(dev);
1967         if (ret != EFI_SUCCESS) {
1968                 tcg2_uninit();
1969                 goto fail;
1970         }
1971
1972         ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol,
1973                                (void *)&efi_tcg2_protocol);
1974         if (ret != EFI_SUCCESS) {
1975                 tcg2_uninit();
1976                 goto fail;
1977         }
1978
1979         ret = efi_create_event(EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,
1980                                efi_tcg2_notify_exit_boot_services, NULL,
1981                                NULL, &event);
1982         if (ret != EFI_SUCCESS) {
1983                 tcg2_uninit();
1984                 goto fail;
1985         }
1986
1987         ret = tcg2_measure_secure_boot_variable(dev);
1988         if (ret != EFI_SUCCESS) {
1989                 tcg2_uninit();
1990                 goto fail;
1991         }
1992
1993         return ret;
1994
1995 fail:
1996         log_err("Cannot install EFI_TCG2_PROTOCOL\n");
1997         /*
1998          * Return EFI_SUCCESS and don't stop the EFI subsystem.
1999          * That's done for 2 reasons
2000          * - If the protocol is not installed the PCRs won't be extended.  So
2001          *   someone later in the boot flow will notice that and take the
2002          *   necessary actions.
2003          * - The TPM sandbox is limited and we won't be able to run any efi
2004          *   related tests with TCG2 enabled
2005          */
2006         return EFI_SUCCESS;
2007 }