include/tpm.h

   1 /*
   2  * Copyright (c) 2013 The Chromium OS Authors.
   3  * Coypright (c) 2013 Guntermann & Drunck GmbH
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #ifndef __TPM_H
   9 #define __TPM_H
  10
  11 /*
  12  * Here is a partial implementation of TPM commands.  Please consult TCG Main
  13  * Specification for definitions of TPM commands.
  14  */
  15
  16 #define TPM_HEADER_SIZE         10
  17
  18 enum tpm_duration {
  19         TPM_SHORT = 0,
  20         TPM_MEDIUM = 1,
  21         TPM_LONG = 2,
  22         TPM_UNDEFINED,
  23
  24         TPM_DURATION_COUNT,
  25 };
  26
  27 enum tpm_startup_type {
  28         TPM_ST_CLEAR            = 0x0001,
  29         TPM_ST_STATE            = 0x0002,
  30         TPM_ST_DEACTIVATED      = 0x0003,
  31 };
  32
  33 enum tpm_physical_presence {
  34         TPM_PHYSICAL_PRESENCE_HW_DISABLE        = 0x0200,
  35         TPM_PHYSICAL_PRESENCE_CMD_DISABLE       = 0x0100,
  36         TPM_PHYSICAL_PRESENCE_LIFETIME_LOCK     = 0x0080,
  37         TPM_PHYSICAL_PRESENCE_HW_ENABLE         = 0x0040,
  38         TPM_PHYSICAL_PRESENCE_CMD_ENABLE        = 0x0020,
  39         TPM_PHYSICAL_PRESENCE_NOTPRESENT        = 0x0010,
  40         TPM_PHYSICAL_PRESENCE_PRESENT           = 0x0008,
  41         TPM_PHYSICAL_PRESENCE_LOCK              = 0x0004,
  42 };
  43
  44 enum tpm_nv_index {
  45         TPM_NV_INDEX_LOCK       = 0xffffffff,
  46         TPM_NV_INDEX_0          = 0x00000000,
  47         TPM_NV_INDEX_DIR        = 0x10000001,
  48 };
  49
  50 enum tpm_resource_type {
  51         TPM_RT_KEY      = 0x00000001,
  52         TPM_RT_AUTH     = 0x00000002,
  53         TPM_RT_HASH     = 0x00000003,
  54         TPM_RT_TRANS    = 0x00000004,
  55         TPM_RT_CONTEXT  = 0x00000005,
  56         TPM_RT_COUNTER  = 0x00000006,
  57         TPM_RT_DELEGATE = 0x00000007,
  58         TPM_RT_DAA_TPM  = 0x00000008,
  59         TPM_RT_DAA_V0   = 0x00000009,
  60         TPM_RT_DAA_V1   = 0x0000000A,
  61 };
  62
  63 enum tpm_capability_areas {
  64         TPM_CAP_ORD             = 0x00000001,
  65         TPM_CAP_ALG             = 0x00000002,
  66         TPM_CAP_PID             = 0x00000003,
  67         TPM_CAP_FLAG            = 0x00000004,
  68         TPM_CAP_PROPERTY        = 0x00000005,
  69         TPM_CAP_VERSION         = 0x00000006,
  70         TPM_CAP_KEY_HANDLE      = 0x00000007,
  71         TPM_CAP_CHECK_LOADED    = 0x00000008,
  72         TPM_CAP_SYM_MODE        = 0x00000009,
  73         TPM_CAP_KEY_STATUS      = 0x0000000C,
  74         TPM_CAP_NV_LIST         = 0x0000000D,
  75         TPM_CAP_MFR             = 0x00000010,
  76         TPM_CAP_NV_INDEX        = 0x00000011,
  77         TPM_CAP_TRANS_ALG       = 0x00000012,
  78         TPM_CAP_HANDLE          = 0x00000014,
  79         TPM_CAP_TRANS_ES        = 0x00000015,
  80         TPM_CAP_AUTH_ENCRYPT    = 0x00000017,
  81         TPM_CAP_SELECT_SIZE     = 0x00000018,
  82         TPM_CAP_DA_LOGIC        = 0x00000019,
  83         TPM_CAP_VERSION_VAL     = 0x0000001A,
  84 };
  85
  86 #define TPM_NV_PER_GLOBALLOCK           (1U << 15)
  87 #define TPM_NV_PER_PPWRITE              (1U << 0)
  88 #define TPM_NV_PER_READ_STCLEAR         (1U << 31)
  89 #define TPM_NV_PER_WRITE_STCLEAR        (1U << 14)
  90
  91 enum {
  92         TPM_PUBEK_SIZE                  = 256,
  93 };
  94
  95 /**
  96  * TPM return codes as defined in the TCG Main specification
  97  * (TPM Main Part 2 Structures; Specification version 1.2)
  98  */
  99 enum tpm_return_code {
 100         TPM_BASE        = 0x00000000,
 101         TPM_NON_FATAL   = 0x00000800,
 102         TPM_SUCCESS     = TPM_BASE,
 103         /* TPM-defined fatal error codes */
 104         TPM_AUTHFAIL                    = TPM_BASE +  1,
 105         TPM_BADINDEX                    = TPM_BASE +  2,
 106         TPM_BAD_PARAMETER               = TPM_BASE +  3,
 107         TPM_AUDITFAILURE                = TPM_BASE +  4,
 108         TPM_CLEAR_DISABLED              = TPM_BASE +  5,
 109         TPM_DEACTIVATED                 = TPM_BASE +  6,
 110         TPM_DISABLED                    = TPM_BASE +  7,
 111         TPM_DISABLED_CMD                = TPM_BASE +  8,
 112         TPM_FAIL                        = TPM_BASE +  9,
 113         TPM_BAD_ORDINAL                 = TPM_BASE + 10,
 114         TPM_INSTALL_DISABLED            = TPM_BASE + 11,
 115         TPM_INVALID_KEYHANDLE           = TPM_BASE + 12,
 116         TPM_KEYNOTFOUND                 = TPM_BASE + 13,
 117         TPM_INAPPROPRIATE_ENC           = TPM_BASE + 14,
 118         TPM_MIGRATE_FAIL                = TPM_BASE + 15,
 119         TPM_INVALID_PCR_INFO            = TPM_BASE + 16,
 120         TPM_NOSPACE                     = TPM_BASE + 17,
 121         TPM_NOSRK                       = TPM_BASE + 18,
 122         TPM_NOTSEALED_BLOB              = TPM_BASE + 19,
 123         TPM_OWNER_SET                   = TPM_BASE + 20,
 124         TPM_RESOURCES                   = TPM_BASE + 21,
 125         TPM_SHORTRANDOM                 = TPM_BASE + 22,
 126         TPM_SIZE                        = TPM_BASE + 23,
 127         TPM_WRONGPCRVAL                 = TPM_BASE + 24,
 128         TPM_BAD_PARAM_SIZE              = TPM_BASE + 25,
 129         TPM_SHA_THREAD                  = TPM_BASE + 26,
 130         TPM_SHA_ERROR                   = TPM_BASE + 27,
 131         TPM_FAILEDSELFTEST              = TPM_BASE + 28,
 132         TPM_AUTH2FAIL                   = TPM_BASE + 29,
 133         TPM_BADTAG                      = TPM_BASE + 30,
 134         TPM_IOERROR                     = TPM_BASE + 31,
 135         TPM_ENCRYPT_ERROR               = TPM_BASE + 32,
 136         TPM_DECRYPT_ERROR               = TPM_BASE + 33,
 137         TPM_INVALID_AUTHHANDLE          = TPM_BASE + 34,
 138         TPM_NO_ENDORSEMENT              = TPM_BASE + 35,
 139         TPM_INVALID_KEYUSAGE            = TPM_BASE + 36,
 140         TPM_WRONG_ENTITYTYPE            = TPM_BASE + 37,
 141         TPM_INVALID_POSTINIT            = TPM_BASE + 38,
 142         TPM_INAPPROPRIATE_SIG           = TPM_BASE + 39,
 143         TPM_BAD_KEY_PROPERTY            = TPM_BASE + 40,
 144         TPM_BAD_MIGRATION               = TPM_BASE + 41,
 145         TPM_BAD_SCHEME                  = TPM_BASE + 42,
 146         TPM_BAD_DATASIZE                = TPM_BASE + 43,
 147         TPM_BAD_MODE                    = TPM_BASE + 44,
 148         TPM_BAD_PRESENCE                = TPM_BASE + 45,
 149         TPM_BAD_VERSION                 = TPM_BASE + 46,
 150         TPM_NO_WRAP_TRANSPORT           = TPM_BASE + 47,
 151         TPM_AUDITFAIL_UNSUCCESSFUL      = TPM_BASE + 48,
 152         TPM_AUDITFAIL_SUCCESSFUL        = TPM_BASE + 49,
 153         TPM_NOTRESETABLE                = TPM_BASE + 50,
 154         TPM_NOTLOCAL                    = TPM_BASE + 51,
 155         TPM_BAD_TYPE                    = TPM_BASE + 52,
 156         TPM_INVALID_RESOURCE            = TPM_BASE + 53,
 157         TPM_NOTFIPS                     = TPM_BASE + 54,
 158         TPM_INVALID_FAMILY              = TPM_BASE + 55,
 159         TPM_NO_NV_PERMISSION            = TPM_BASE + 56,
 160         TPM_REQUIRES_SIGN               = TPM_BASE + 57,
 161         TPM_KEY_NOTSUPPORTED            = TPM_BASE + 58,
 162         TPM_AUTH_CONFLICT               = TPM_BASE + 59,
 163         TPM_AREA_LOCKED                 = TPM_BASE + 60,
 164         TPM_BAD_LOCALITY                = TPM_BASE + 61,
 165         TPM_READ_ONLY                   = TPM_BASE + 62,
 166         TPM_PER_NOWRITE                 = TPM_BASE + 63,
 167         TPM_FAMILY_COUNT                = TPM_BASE + 64,
 168         TPM_WRITE_LOCKED                = TPM_BASE + 65,
 169         TPM_BAD_ATTRIBUTES              = TPM_BASE + 66,
 170         TPM_INVALID_STRUCTURE           = TPM_BASE + 67,
 171         TPM_KEY_OWNER_CONTROL           = TPM_BASE + 68,
 172         TPM_BAD_COUNTER                 = TPM_BASE + 69,
 173         TPM_NOT_FULLWRITE               = TPM_BASE + 70,
 174         TPM_CONTEXT_GAP                 = TPM_BASE + 71,
 175         TPM_MAXNVWRITES                 = TPM_BASE + 72,
 176         TPM_NOOPERATOR                  = TPM_BASE + 73,
 177         TPM_RESOURCEMISSING             = TPM_BASE + 74,
 178         TPM_DELEGATE_LOCK               = TPM_BASE + 75,
 179         TPM_DELEGATE_FAMILY             = TPM_BASE + 76,
 180         TPM_DELEGATE_ADMIN              = TPM_BASE + 77,
 181         TPM_TRANSPORT_NOTEXCLUSIVE      = TPM_BASE + 78,
 182         TPM_OWNER_CONTROL               = TPM_BASE + 79,
 183         TPM_DAA_RESOURCES               = TPM_BASE + 80,
 184         TPM_DAA_INPUT_DATA0             = TPM_BASE + 81,
 185         TPM_DAA_INPUT_DATA1             = TPM_BASE + 82,
 186         TPM_DAA_ISSUER_SETTINGS         = TPM_BASE + 83,
 187         TPM_DAA_TPM_SETTINGS            = TPM_BASE + 84,
 188         TPM_DAA_STAGE                   = TPM_BASE + 85,
 189         TPM_DAA_ISSUER_VALIDITY         = TPM_BASE + 86,
 190         TPM_DAA_WRONG_W                 = TPM_BASE + 87,
 191         TPM_BAD_HANDLE                  = TPM_BASE + 88,
 192         TPM_BAD_DELEGATE                = TPM_BASE + 89,
 193         TPM_BADCONTEXT                  = TPM_BASE + 90,
 194         TPM_TOOMANYCONTEXTS             = TPM_BASE + 91,
 195         TPM_MA_TICKET_SIGNATURE         = TPM_BASE + 92,
 196         TPM_MA_DESTINATION              = TPM_BASE + 93,
 197         TPM_MA_SOURCE                   = TPM_BASE + 94,
 198         TPM_MA_AUTHORITY                = TPM_BASE + 95,
 199         TPM_PERMANENTEK                 = TPM_BASE + 97,
 200         TPM_BAD_SIGNATURE               = TPM_BASE + 98,
 201         TPM_NOCONTEXTSPACE              = TPM_BASE + 99,
 202         /* TPM-defined non-fatal errors */
 203         TPM_RETRY               = TPM_BASE + TPM_NON_FATAL,
 204         TPM_NEEDS_SELFTEST      = TPM_BASE + TPM_NON_FATAL + 1,
 205         TPM_DOING_SELFTEST      = TPM_BASE + TPM_NON_FATAL + 2,
 206         TPM_DEFEND_LOCK_RUNNING = TPM_BASE + TPM_NON_FATAL + 3,
 207 };
 208
 209 struct tpm_permanent_flags {
 210         __be16  tag;
 211         u8      disable;
 212         u8      ownership;
 213         u8      deactivated;
 214         u8      read_pubek;
 215         u8      disable_owner_clear;
 216         u8      allow_maintenance;
 217         u8      physical_presence_lifetime_lock;
 218         u8      physical_presence_hw_enable;
 219         u8      physical_presence_cmd_enable;
 220         u8      cekp_used;
 221         u8      tpm_post;
 222         u8      tpm_post_lock;
 223         u8      fips;
 224         u8      operator;
 225         u8      enable_revoke_ek;
 226         u8      nv_locked;
 227         u8      read_srk_pub;
 228         u8      tpm_established;
 229         u8      maintenance_done;
 230         u8      disable_full_da_logic_info;
 231 } __packed;
 232
 233 /* Max buffer size supported by our tpm */
 234 #define TPM_DEV_BUFSIZE         1260
 235
 236 /**
 237  * struct tpm_chip_priv - Information about a TPM, stored by the uclass
 238  *
 239  * These values must be set up by the device's probe() method before
 240  * communcation is attempted. If the device has an xfer() method, this is
 241  * not needed. There is no need to set up @buf.
 242  *
 243  * @duration_ms:        Length of each duration type in milliseconds
 244  * @retry_time_ms:      Time to wait before retrying receive
 245  */
 246 struct tpm_chip_priv {
 247         uint duration_ms[TPM_DURATION_COUNT];
 248         uint retry_time_ms;
 249         u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)];  /* Max buffer size + addr */
 250 };
 251
 252 /**
 253  * struct tpm_ops - low-level TPM operations
 254  *
 255  * These are designed to avoid loops and delays in the driver itself. These
 256  * should be handled in the uclass.
 257  *
 258  * In gneral you should implement everything except xfer(). Where you need
 259  * complete control of the transfer, then xfer() can be provided and will
 260  * override the other methods.
 261  *
 262  * This interface is for low-level TPM access. It does not understand the
 263  * concept of localities or the various TPM messages. That interface is
 264  * defined in the functions later on in this file, but they all translate
 265  * to bytes which are sent and received.
 266  */
 267 struct tpm_ops {
 268         /**
 269          * open() - Request access to locality 0 for the caller
 270          *
 271          * After all commands have been completed the caller should call
 272          * close().
 273          *
 274          * @dev:        Device to close
 275          * @return 0 ok OK, -ve on error
 276          */
 277         int (*open)(struct udevice *dev);
 278
 279         /**
 280          * close() - Close the current session
 281          *
 282          * Releasing the locked locality. Returns 0 on success, -ve 1 on
 283          * failure (in case lock removal did not succeed).
 284          *
 285          * @dev:        Device to close
 286          * @return 0 ok OK, -ve on error
 287          */
 288         int (*close)(struct udevice *dev);
 289
 290         /**
 291          * get_desc() - Get a text description of the TPM
 292          *
 293          * @dev:        Device to check
 294          * @buf:        Buffer to put the string
 295          * @size:       Maximum size of buffer
 296          * @return length of string, or -ENOSPC it no space
 297          */
 298         int (*get_desc)(struct udevice *dev, char *buf, int size);
 299
 300         /**
 301          * send() - send data to the TPM
 302          *
 303          * @dev:        Device to talk to
 304          * @sendbuf:    Buffer of the data to send
 305          * @send_size:  Size of the data to send
 306          *
 307          * Returns 0 on success or -ve on failure.
 308          */
 309         int (*send)(struct udevice *dev, const uint8_t *sendbuf,
 310                     size_t send_size);
 311
 312         /**
 313          * recv() - receive a response from the TPM
 314          *
 315          * @dev:        Device to talk to
 316          * @recvbuf:    Buffer to save the response to
 317          * @max_size:   Maximum number of bytes to receive
 318          *
 319          * Returns number of bytes received on success, -EAGAIN if the TPM
 320          * response is not ready, -EINTR if cancelled, or other -ve value on
 321          * failure.
 322          */
 323         int (*recv)(struct udevice *dev, uint8_t *recvbuf, size_t max_size);
 324
 325         /**
 326          * cleanup() - clean up after an operation in progress
 327          *
 328          * This is called if receiving times out. The TPM may need to abort
 329          * the current transaction if it did not complete, and make itself
 330          * ready for another.
 331          *
 332          * @dev:        Device to talk to
 333          */
 334         int (*cleanup)(struct udevice *dev);
 335
 336         /**
 337          * xfer() - send data to the TPM and get response
 338          *
 339          * This method is optional. If it exists it is used in preference
 340          * to send(), recv() and cleanup(). It should handle all aspects of
 341          * TPM communication for a single transfer.
 342          *
 343          * @dev:        Device to talk to
 344          * @sendbuf:    Buffer of the data to send
 345          * @send_size:  Size of the data to send
 346          * @recvbuf:    Buffer to save the response to
 347          * @recv_size:  Pointer to the size of the response buffer
 348          *
 349          * Returns 0 on success (and places the number of response bytes at
 350          * recv_size) or -ve on failure.
 351          */
 352         int (*xfer)(struct udevice *dev, const uint8_t *sendbuf,
 353                     size_t send_size, uint8_t *recvbuf, size_t *recv_size);
 354 };
 355
 356 #define tpm_get_ops(dev)        ((struct tpm_ops *)device_get_ops(dev))
 357
 358 /**
 359  * tpm_open() - Request access to locality 0 for the caller
 360  *
 361  * After all commands have been completed the caller is supposed to
 362  * call tpm_close().
 363  *
 364  * Returns 0 on success, -ve on failure.
 365  */
 366 int tpm_open(struct udevice *dev);
 367
 368 /**
 369  * tpm_close() - Close the current session
 370  *
 371  * Releasing the locked locality. Returns 0 on success, -ve 1 on
 372  * failure (in case lock removal did not succeed).
 373  */
 374 int tpm_close(struct udevice *dev);
 375
 376 /**
 377  * tpm_get_desc() - Get a text description of the TPM
 378  *
 379  * @dev:        Device to check
 380  * @buf:        Buffer to put the string
 381  * @size:       Maximum size of buffer
 382  * @return length of string, or -ENOSPC it no space
 383  */
 384 int tpm_get_desc(struct udevice *dev, char *buf, int size);
 385
 386 /**
 387  * tpm_xfer() - send data to the TPM and get response
 388  *
 389  * This first uses the device's send() method to send the bytes. Then it calls
 390  * recv() to get the reply. If recv() returns -EAGAIN then it will delay a
 391  * short time and then call recv() again.
 392  *
 393  * Regardless of whether recv() completes successfully, it will then call
 394  * cleanup() to finish the transaction.
 395  *
 396  * Note that the outgoing data is inspected to determine command type
 397  * (ordinal) and a timeout is used for that command type.
 398  *
 399  * @sendbuf - buffer of the data to send
 400  * @send_size size of the data to send
 401  * @recvbuf - memory to save the response to
 402  * @recv_len - pointer to the size of the response buffer
 403  *
 404  * Returns 0 on success (and places the number of response bytes at
 405  * recv_len) or -ve on failure.
 406  */
 407 int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size,
 408              uint8_t *recvbuf, size_t *recv_size);
 409
 410 /**
 411  * Initialize TPM device.  It must be called before any TPM commands.
 412  *
 413  * @return 0 on success, non-0 on error.
 414  */
 415 int tpm_init(void);
 416
 417 /**
 418  * Issue a TPM_Startup command.
 419  *
 420  * @param mode          TPM startup mode
 421  * @return return code of the operation
 422  */
 423 uint32_t tpm_startup(enum tpm_startup_type mode);
 424
 425 /**
 426  * Issue a TPM_SelfTestFull command.
 427  *
 428  * @return return code of the operation
 429  */
 430 uint32_t tpm_self_test_full(void);
 431
 432 /**
 433  * Issue a TPM_ContinueSelfTest command.
 434  *
 435  * @return return code of the operation
 436  */
 437 uint32_t tpm_continue_self_test(void);
 438
 439 /**
 440  * Issue a TPM_NV_DefineSpace command.  The implementation is limited
 441  * to specify TPM_NV_ATTRIBUTES and size of the area.  The area index
 442  * could be one of the special value listed in enum tpm_nv_index.
 443  *
 444  * @param index         index of the area
 445  * @param perm          TPM_NV_ATTRIBUTES of the area
 446  * @param size          size of the area
 447  * @return return code of the operation
 448  */
 449 uint32_t tpm_nv_define_space(uint32_t index, uint32_t perm, uint32_t size);
 450
 451 /**
 452  * Issue a TPM_NV_ReadValue command.  This implementation is limited
 453  * to read the area from offset 0.  The area index could be one of
 454  * the special value listed in enum tpm_nv_index.
 455  *
 456  * @param index         index of the area
 457  * @param data          output buffer of the area contents
 458  * @param count         size of output buffer
 459  * @return return code of the operation
 460  */
 461 uint32_t tpm_nv_read_value(uint32_t index, void *data, uint32_t count);
 462
 463 /**
 464  * Issue a TPM_NV_WriteValue command.  This implementation is limited
 465  * to write the area from offset 0.  The area index could be one of
 466  * the special value listed in enum tpm_nv_index.
 467  *
 468  * @param index         index of the area
 469  * @param data          input buffer to be wrote to the area
 470  * @param length        length of data bytes of input buffer
 471  * @return return code of the operation
 472  */
 473 uint32_t tpm_nv_write_value(uint32_t index, const void *data, uint32_t length);
 474
 475 /**
 476  * Issue a TPM_Extend command.
 477  *
 478  * @param index         index of the PCR
 479  * @param in_digest     160-bit value representing the event to be
 480  *                      recorded
 481  * @param out_digest    160-bit PCR value after execution of the
 482  *                      command
 483  * @return return code of the operation
 484  */
 485 uint32_t tpm_extend(uint32_t index, const void *in_digest, void *out_digest);
 486
 487 /**
 488  * Issue a TPM_PCRRead command.
 489  *
 490  * @param index         index of the PCR
 491  * @param data          output buffer for contents of the named PCR
 492  * @param count         size of output buffer
 493  * @return return code of the operation
 494  */
 495 uint32_t tpm_pcr_read(uint32_t index, void *data, size_t count);
 496
 497 /**
 498  * Issue a TSC_PhysicalPresence command.  TPM physical presence flag
 499  * is bit-wise OR'ed of flags listed in enum tpm_physical_presence.
 500  *
 501  * @param presence      TPM physical presence flag
 502  * @return return code of the operation
 503  */
 504 uint32_t tpm_tsc_physical_presence(uint16_t presence);
 505
 506 /**
 507  * Issue a TPM_ReadPubek command.
 508  *
 509  * @param data          output buffer for the public endorsement key
 510  * @param count         size of ouput buffer
 511  * @return return code of the operation
 512  */
 513 uint32_t tpm_read_pubek(void *data, size_t count);
 514
 515 /**
 516  * Issue a TPM_ForceClear command.
 517  *
 518  * @return return code of the operation
 519  */
 520 uint32_t tpm_force_clear(void);
 521
 522 /**
 523  * Issue a TPM_PhysicalEnable command.
 524  *
 525  * @return return code of the operation
 526  */
 527 uint32_t tpm_physical_enable(void);
 528
 529 /**
 530  * Issue a TPM_PhysicalDisable command.
 531  *
 532  * @return return code of the operation
 533  */
 534 uint32_t tpm_physical_disable(void);
 535
 536 /**
 537  * Issue a TPM_PhysicalSetDeactivated command.
 538  *
 539  * @param state         boolean state of the deactivated flag
 540  * @return return code of the operation
 541  */
 542 uint32_t tpm_physical_set_deactivated(uint8_t state);
 543
 544 /**
 545  * Issue a TPM_GetCapability command.  This implementation is limited
 546  * to query sub_cap index that is 4-byte wide.
 547  *
 548  * @param cap_area      partition of capabilities
 549  * @param sub_cap       further definition of capability, which is
 550  *                      limited to be 4-byte wide
 551  * @param cap           output buffer for capability information
 552  * @param count         size of ouput buffer
 553  * @return return code of the operation
 554  */
 555 uint32_t tpm_get_capability(uint32_t cap_area, uint32_t sub_cap,
 556                 void *cap, size_t count);
 557
 558 /**
 559  * Issue a TPM_FlushSpecific command for a AUTH ressource.
 560  *
 561  * @param auth_handle   handle of the auth session
 562  * @return return code of the operation
 563  */
 564 uint32_t tpm_terminate_auth_session(uint32_t auth_handle);
 565
 566 /**
 567  * Issue a TPM_OIAP command to setup an object independant authorization
 568  * session.
 569  * Information about the session is stored internally.
 570  * If there was already an OIAP session active it is terminated and a new
 571  * session is set up.
 572  *
 573  * @param auth_handle   pointer to the (new) auth handle or NULL.
 574  * @return return code of the operation
 575  */
 576 uint32_t tpm_oiap(uint32_t *auth_handle);
 577
 578 /**
 579  * Ends an active OIAP session.
 580  *
 581  * @return return code of the operation
 582  */
 583 uint32_t tpm_end_oiap(void);
 584
 585 /**
 586  * Issue a TPM_LoadKey2 (Auth1) command using an OIAP session for authenticating
 587  * the usage of the parent key.
 588  *
 589  * @param parent_handle handle of the parent key.
 590  * @param key           pointer to the key structure (TPM_KEY or TPM_KEY12).
 591  * @param key_length    size of the key structure
 592  * @param parent_key_usage_auth usage auth for the parent key
 593  * @param key_handle    pointer to the key handle
 594  * @return return code of the operation
 595  */
 596 uint32_t tpm_load_key2_oiap(uint32_t parent_handle,
 597                 const void *key, size_t key_length,
 598                 const void *parent_key_usage_auth,
 599                 uint32_t *key_handle);
 600
 601 /**
 602  * Issue a TPM_GetPubKey (Auth1) command using an OIAP session for
 603  * authenticating the usage of the key.
 604  *
 605  * @param key_handle    handle of the key
 606  * @param usage_auth    usage auth for the key
 607  * @param pubkey        pointer to the pub key buffer; may be NULL if the pubkey
 608  *                      should not be stored.
 609  * @param pubkey_len    pointer to the pub key buffer len. On entry: the size of
 610  *                      the provided pubkey buffer. On successful exit: the size
 611  *                      of the stored TPM_PUBKEY structure (iff pubkey != NULL).
 612  * @return return code of the operation
 613  */
 614 uint32_t tpm_get_pub_key_oiap(uint32_t key_handle, const void *usage_auth,
 615                 void *pubkey, size_t *pubkey_len);
 616
 617 /**
 618  * Get the TPM permanent flags value
 619  *
 620  * @param pflags        Place to put permanent flags
 621  * @return return code of the operation
 622  */
 623 uint32_t tpm_get_permanent_flags(struct tpm_permanent_flags *pflags);
 624
 625 /**
 626  * Get the TPM permissions
 627  *
 628  * @param perm          Returns permissions value
 629  * @return return code of the operation
 630  */
 631 uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm);
 632
 633 /**
 634  * Flush a resource with a given handle and type from the TPM
 635  *
 636  * @param key_handle           handle of the resource
 637  * @param resource_type                type of the resource
 638  * @return return code of the operation
 639  */
 640 uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type);
 641
 642 #ifdef CONFIG_TPM_LOAD_KEY_BY_SHA1
 643 /**
 644  * Search for a key by usage AuthData and the hash of the parent's pub key.
 645  *
 646  * @param auth          Usage auth of the key to search for
 647  * @param pubkey_digest SHA1 hash of the pub key structure of the key
 648  * @param[out] handle   The handle of the key (Non-null iff found)
 649  * @return 0 if key was found in TPM; != 0 if not.
 650  */
 651 uint32_t tpm_find_key_sha1(const uint8_t auth[20], const uint8_t
 652                            pubkey_digest[20], uint32_t *handle);
 653 #endif /* CONFIG_TPM_LOAD_KEY_BY_SHA1 */
 654 #endif /* __TPM_H */