drivers/char/tpm/tpm2-cmd.c

   1 /*
   2  * Copyright (C) 2014, 2015 Intel Corporation
   3  *
   4  * Authors:
   5  * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
   6  *
   7  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
   8  *
   9  * This file contains TPM2 protocol implementations of the commands
  10  * used by the kernel internally.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; version 2
  15  * of the License.
  16  */
  17
  18 #include "tpm.h"
  19 #include <keys/trusted-type.h>
  20
  21 enum tpm2_object_attributes {
  22         TPM2_ATTR_USER_WITH_AUTH        = BIT(6),
  23 };
  24
  25 struct tpm2_startup_in {
  26         __be16  startup_type;
  27 } __packed;
  28
  29 struct tpm2_self_test_in {
  30         u8      full_test;
  31 } __packed;
  32
  33 struct tpm2_pcr_read_in {
  34         __be32  pcr_selects_cnt;
  35         __be16  hash_alg;
  36         u8      pcr_select_size;
  37         u8      pcr_select[TPM2_PCR_SELECT_MIN];
  38 } __packed;
  39
  40 struct tpm2_pcr_read_out {
  41         __be32  update_cnt;
  42         __be32  pcr_selects_cnt;
  43         __be16  hash_alg;
  44         u8      pcr_select_size;
  45         u8      pcr_select[TPM2_PCR_SELECT_MIN];
  46         __be32  digests_cnt;
  47         __be16  digest_size;
  48         u8      digest[TPM_DIGEST_SIZE];
  49 } __packed;
  50
  51 struct tpm2_null_auth_area {
  52         __be32                  handle;
  53         __be16                  nonce_size;
  54         u8                      attributes;
  55         __be16                  auth_size;
  56 } __packed;
  57
  58 struct tpm2_pcr_extend_in {
  59         __be32                          pcr_idx;
  60         __be32                          auth_area_size;
  61         struct tpm2_null_auth_area      auth_area;
  62         __be32                          digest_cnt;
  63         __be16                          hash_alg;
  64         u8                              digest[TPM_DIGEST_SIZE];
  65 } __packed;
  66
  67 struct tpm2_get_tpm_pt_in {
  68         __be32  cap_id;
  69         __be32  property_id;
  70         __be32  property_cnt;
  71 } __packed;
  72
  73 struct tpm2_get_tpm_pt_out {
  74         u8      more_data;
  75         __be32  subcap_id;
  76         __be32  property_cnt;
  77         __be32  property_id;
  78         __be32  value;
  79 } __packed;
  80
  81 struct tpm2_get_random_in {
  82         __be16  size;
  83 } __packed;
  84
  85 struct tpm2_get_random_out {
  86         __be16  size;
  87         u8      buffer[TPM_MAX_RNG_DATA];
  88 } __packed;
  89
  90 union tpm2_cmd_params {
  91         struct  tpm2_startup_in         startup_in;
  92         struct  tpm2_self_test_in       selftest_in;
  93         struct  tpm2_pcr_read_in        pcrread_in;
  94         struct  tpm2_pcr_read_out       pcrread_out;
  95         struct  tpm2_pcr_extend_in      pcrextend_in;
  96         struct  tpm2_get_tpm_pt_in      get_tpm_pt_in;
  97         struct  tpm2_get_tpm_pt_out     get_tpm_pt_out;
  98         struct  tpm2_get_random_in      getrandom_in;
  99         struct  tpm2_get_random_out     getrandom_out;
 100 };
 101
 102 struct tpm2_cmd {
 103         tpm_cmd_header          header;
 104         union tpm2_cmd_params   params;
 105 } __packed;
 106
 107 /*
 108  * Array with one entry per ordinal defining the maximum amount
 109  * of time the chip could take to return the result. The values
 110  * of the SHORT, MEDIUM, and LONG durations are taken from the
 111  * PC Client Profile (PTP) specification.
 112  */
 113 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
 114         TPM_UNDEFINED,          /* 11F */
 115         TPM_UNDEFINED,          /* 120 */
 116         TPM_LONG,               /* 121 */
 117         TPM_UNDEFINED,          /* 122 */
 118         TPM_UNDEFINED,          /* 123 */
 119         TPM_UNDEFINED,          /* 124 */
 120         TPM_UNDEFINED,          /* 125 */
 121         TPM_UNDEFINED,          /* 126 */
 122         TPM_UNDEFINED,          /* 127 */
 123         TPM_UNDEFINED,          /* 128 */
 124         TPM_LONG,               /* 129 */
 125         TPM_UNDEFINED,          /* 12a */
 126         TPM_UNDEFINED,          /* 12b */
 127         TPM_UNDEFINED,          /* 12c */
 128         TPM_UNDEFINED,          /* 12d */
 129         TPM_UNDEFINED,          /* 12e */
 130         TPM_UNDEFINED,          /* 12f */
 131         TPM_UNDEFINED,          /* 130 */
 132         TPM_UNDEFINED,          /* 131 */
 133         TPM_UNDEFINED,          /* 132 */
 134         TPM_UNDEFINED,          /* 133 */
 135         TPM_UNDEFINED,          /* 134 */
 136         TPM_UNDEFINED,          /* 135 */
 137         TPM_UNDEFINED,          /* 136 */
 138         TPM_UNDEFINED,          /* 137 */
 139         TPM_UNDEFINED,          /* 138 */
 140         TPM_UNDEFINED,          /* 139 */
 141         TPM_UNDEFINED,          /* 13a */
 142         TPM_UNDEFINED,          /* 13b */
 143         TPM_UNDEFINED,          /* 13c */
 144         TPM_UNDEFINED,          /* 13d */
 145         TPM_MEDIUM,             /* 13e */
 146         TPM_UNDEFINED,          /* 13f */
 147         TPM_UNDEFINED,          /* 140 */
 148         TPM_UNDEFINED,          /* 141 */
 149         TPM_UNDEFINED,          /* 142 */
 150         TPM_LONG,               /* 143 */
 151         TPM_MEDIUM,             /* 144 */
 152         TPM_UNDEFINED,          /* 145 */
 153         TPM_UNDEFINED,          /* 146 */
 154         TPM_UNDEFINED,          /* 147 */
 155         TPM_UNDEFINED,          /* 148 */
 156         TPM_UNDEFINED,          /* 149 */
 157         TPM_UNDEFINED,          /* 14a */
 158         TPM_UNDEFINED,          /* 14b */
 159         TPM_UNDEFINED,          /* 14c */
 160         TPM_UNDEFINED,          /* 14d */
 161         TPM_LONG,               /* 14e */
 162         TPM_UNDEFINED,          /* 14f */
 163         TPM_UNDEFINED,          /* 150 */
 164         TPM_UNDEFINED,          /* 151 */
 165         TPM_UNDEFINED,          /* 152 */
 166         TPM_UNDEFINED,          /* 153 */
 167         TPM_UNDEFINED,          /* 154 */
 168         TPM_UNDEFINED,          /* 155 */
 169         TPM_UNDEFINED,          /* 156 */
 170         TPM_UNDEFINED,          /* 157 */
 171         TPM_UNDEFINED,          /* 158 */
 172         TPM_UNDEFINED,          /* 159 */
 173         TPM_UNDEFINED,          /* 15a */
 174         TPM_UNDEFINED,          /* 15b */
 175         TPM_MEDIUM,             /* 15c */
 176         TPM_UNDEFINED,          /* 15d */
 177         TPM_UNDEFINED,          /* 15e */
 178         TPM_UNDEFINED,          /* 15f */
 179         TPM_UNDEFINED,          /* 160 */
 180         TPM_UNDEFINED,          /* 161 */
 181         TPM_UNDEFINED,          /* 162 */
 182         TPM_UNDEFINED,          /* 163 */
 183         TPM_UNDEFINED,          /* 164 */
 184         TPM_UNDEFINED,          /* 165 */
 185         TPM_UNDEFINED,          /* 166 */
 186         TPM_UNDEFINED,          /* 167 */
 187         TPM_UNDEFINED,          /* 168 */
 188         TPM_UNDEFINED,          /* 169 */
 189         TPM_UNDEFINED,          /* 16a */
 190         TPM_UNDEFINED,          /* 16b */
 191         TPM_UNDEFINED,          /* 16c */
 192         TPM_UNDEFINED,          /* 16d */
 193         TPM_UNDEFINED,          /* 16e */
 194         TPM_UNDEFINED,          /* 16f */
 195         TPM_UNDEFINED,          /* 170 */
 196         TPM_UNDEFINED,          /* 171 */
 197         TPM_UNDEFINED,          /* 172 */
 198         TPM_UNDEFINED,          /* 173 */
 199         TPM_UNDEFINED,          /* 174 */
 200         TPM_UNDEFINED,          /* 175 */
 201         TPM_UNDEFINED,          /* 176 */
 202         TPM_LONG,               /* 177 */
 203         TPM_UNDEFINED,          /* 178 */
 204         TPM_UNDEFINED,          /* 179 */
 205         TPM_MEDIUM,             /* 17a */
 206         TPM_LONG,               /* 17b */
 207         TPM_UNDEFINED,          /* 17c */
 208         TPM_UNDEFINED,          /* 17d */
 209         TPM_UNDEFINED,          /* 17e */
 210         TPM_UNDEFINED,          /* 17f */
 211         TPM_UNDEFINED,          /* 180 */
 212         TPM_UNDEFINED,          /* 181 */
 213         TPM_MEDIUM,             /* 182 */
 214         TPM_UNDEFINED,          /* 183 */
 215         TPM_UNDEFINED,          /* 184 */
 216         TPM_MEDIUM,             /* 185 */
 217         TPM_MEDIUM,             /* 186 */
 218         TPM_UNDEFINED,          /* 187 */
 219         TPM_UNDEFINED,          /* 188 */
 220         TPM_UNDEFINED,          /* 189 */
 221         TPM_UNDEFINED,          /* 18a */
 222         TPM_UNDEFINED,          /* 18b */
 223         TPM_UNDEFINED,          /* 18c */
 224         TPM_UNDEFINED,          /* 18d */
 225         TPM_UNDEFINED,          /* 18e */
 226         TPM_UNDEFINED           /* 18f */
 227 };
 228
 229 #define TPM2_PCR_READ_IN_SIZE \
 230         (sizeof(struct tpm_input_header) + \
 231          sizeof(struct tpm2_pcr_read_in))
 232
 233 static const struct tpm_input_header tpm2_pcrread_header = {
 234         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 235         .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
 236         .ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
 237 };
 238
 239 /**
 240  * tpm2_pcr_read() - read a PCR value
 241  * @chip:       TPM chip to use.
 242  * @pcr_idx:    index of the PCR to read.
 243  * @ref_buf:    buffer to store the resulting hash,
 244  *
 245  * 0 is returned when the operation is successful. If a negative number is
 246  * returned it remarks a POSIX error code. If a positive number is returned
 247  * it remarks a TPM error.
 248  */
 249 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 250 {
 251         int rc;
 252         struct tpm2_cmd cmd;
 253         u8 *buf;
 254
 255         if (pcr_idx >= TPM2_PLATFORM_PCR)
 256                 return -EINVAL;
 257
 258         cmd.header.in = tpm2_pcrread_header;
 259         cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
 260         cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 261         cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
 262
 263         memset(cmd.params.pcrread_in.pcr_select, 0,
 264                sizeof(cmd.params.pcrread_in.pcr_select));
 265         cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
 266
 267         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 268                               "attempting to read a pcr value");
 269         if (rc == 0) {
 270                 buf = cmd.params.pcrread_out.digest;
 271                 memcpy(res_buf, buf, TPM_DIGEST_SIZE);
 272         }
 273
 274         return rc;
 275 }
 276
 277 #define TPM2_GET_PCREXTEND_IN_SIZE \
 278         (sizeof(struct tpm_input_header) + \
 279          sizeof(struct tpm2_pcr_extend_in))
 280
 281 static const struct tpm_input_header tpm2_pcrextend_header = {
 282         .tag = cpu_to_be16(TPM2_ST_SESSIONS),
 283         .length = cpu_to_be32(TPM2_GET_PCREXTEND_IN_SIZE),
 284         .ordinal = cpu_to_be32(TPM2_CC_PCR_EXTEND)
 285 };
 286
 287 /**
 288  * tpm2_pcr_extend() - extend a PCR value
 289  * @chip:       TPM chip to use.
 290  * @pcr_idx:    index of the PCR.
 291  * @hash:       hash value to use for the extend operation.
 292  *
 293  * 0 is returned when the operation is successful. If a negative number is
 294  * returned it remarks a POSIX error code. If a positive number is returned
 295  * it remarks a TPM error.
 296  */
 297 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
 298 {
 299         struct tpm2_cmd cmd;
 300         int rc;
 301
 302         cmd.header.in = tpm2_pcrextend_header;
 303         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 304         cmd.params.pcrextend_in.auth_area_size =
 305                 cpu_to_be32(sizeof(struct tpm2_null_auth_area));
 306         cmd.params.pcrextend_in.auth_area.handle =
 307                 cpu_to_be32(TPM2_RS_PW);
 308         cmd.params.pcrextend_in.auth_area.nonce_size = 0;
 309         cmd.params.pcrextend_in.auth_area.attributes = 0;
 310         cmd.params.pcrextend_in.auth_area.auth_size = 0;
 311         cmd.params.pcrextend_in.digest_cnt = cpu_to_be32(1);
 312         cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 313         memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);
 314
 315         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 316                               "attempting extend a PCR value");
 317
 318         return rc;
 319 }
 320
 321 #define TPM2_GETRANDOM_IN_SIZE \
 322         (sizeof(struct tpm_input_header) + \
 323          sizeof(struct tpm2_get_random_in))
 324
 325 static const struct tpm_input_header tpm2_getrandom_header = {
 326         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 327         .length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
 328         .ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
 329 };
 330
 331 /**
 332  * tpm2_get_random() - get random bytes from the TPM RNG
 333  * @chip: TPM chip to use
 334  * @out: destination buffer for the random bytes
 335  * @max: the max number of bytes to write to @out
 336  *
 337  * 0 is returned when the operation is successful. If a negative number is
 338  * returned it remarks a POSIX error code. If a positive number is returned
 339  * it remarks a TPM error.
 340  */
 341 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
 342 {
 343         struct tpm2_cmd cmd;
 344         u32 recd;
 345         u32 num_bytes;
 346         int err;
 347         int total = 0;
 348         int retries = 5;
 349         u8 *dest = out;
 350
 351         num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
 352
 353         if (!out || !num_bytes ||
 354             max > sizeof(cmd.params.getrandom_out.buffer))
 355                 return -EINVAL;
 356
 357         do {
 358                 cmd.header.in = tpm2_getrandom_header;
 359                 cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
 360
 361                 err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 362                                        "attempting get random");
 363                 if (err)
 364                         break;
 365
 366                 recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
 367                              num_bytes);
 368                 memcpy(dest, cmd.params.getrandom_out.buffer, recd);
 369
 370                 dest += recd;
 371                 total += recd;
 372                 num_bytes -= recd;
 373         } while (retries-- && total < max);
 374
 375         return total ? total : -EIO;
 376 }
 377
 378 #define TPM2_GET_TPM_PT_IN_SIZE \
 379         (sizeof(struct tpm_input_header) + \
 380          sizeof(struct tpm2_get_tpm_pt_in))
 381
 382 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
 383         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 384         .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
 385         .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
 386 };
 387
 388 /**
 389  * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated with
 390  * tpm_buf_alloc().
 391  *
 392  * @param buf: an allocated tpm_buf instance
 393  * @param nonce: the session nonce, may be NULL if not used
 394  * @param nonce_len: the session nonce length, may be 0 if not used
 395  * @param attributes: the session attributes
 396  * @param hmac: the session HMAC or password, may be NULL if not used
 397  * @param hmac_len: the session HMAC or password length, maybe 0 if not used
 398  */
 399 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
 400                                  const u8 *nonce, u16 nonce_len,
 401                                  u8 attributes,
 402                                  const u8 *hmac, u16 hmac_len)
 403 {
 404         tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
 405         tpm_buf_append_u32(buf, session_handle);
 406         tpm_buf_append_u16(buf, nonce_len);
 407
 408         if (nonce && nonce_len)
 409                 tpm_buf_append(buf, nonce, nonce_len);
 410
 411         tpm_buf_append_u8(buf, attributes);
 412         tpm_buf_append_u16(buf, hmac_len);
 413
 414         if (hmac && hmac_len)
 415                 tpm_buf_append(buf, hmac, hmac_len);
 416 }
 417
 418 /**
 419  * tpm2_seal_trusted() - seal a trusted key
 420  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
 421  * @options: authentication values and other options
 422  * @payload: the key data in clear and encrypted form
 423  *
 424  * Returns < 0 on error and 0 on success.
 425  */
 426 int tpm2_seal_trusted(struct tpm_chip *chip,
 427                       struct trusted_key_payload *payload,
 428                       struct trusted_key_options *options)
 429 {
 430         unsigned int blob_len;
 431         struct tpm_buf buf;
 432         int rc;
 433
 434         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
 435         if (rc)
 436                 return rc;
 437
 438         tpm_buf_append_u32(&buf, options->keyhandle);
 439         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 440                              NULL /* nonce */, 0,
 441                              0 /* session_attributes */,
 442                              options->keyauth /* hmac */,
 443                              TPM_DIGEST_SIZE);
 444
 445         /* sensitive */
 446         tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len);
 447
 448         tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
 449         tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
 450         tpm_buf_append_u16(&buf, payload->key_len);
 451         tpm_buf_append(&buf, payload->key, payload->key_len);
 452
 453         /* public */
 454         tpm_buf_append_u16(&buf, 14);
 455
 456         tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
 457         tpm_buf_append_u16(&buf, TPM2_ALG_SHA256);
 458         tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH);
 459         tpm_buf_append_u16(&buf, 0); /* policy digest size */
 460         tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
 461         tpm_buf_append_u16(&buf, 0);
 462
 463         /* outside info */
 464         tpm_buf_append_u16(&buf, 0);
 465
 466         /* creation PCR */
 467         tpm_buf_append_u32(&buf, 0);
 468
 469         if (buf.flags & TPM_BUF_OVERFLOW) {
 470                 rc = -E2BIG;
 471                 goto out;
 472         }
 473
 474         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "sealing data");
 475         if (rc)
 476                 goto out;
 477
 478         blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
 479         if (blob_len > MAX_BLOB_SIZE) {
 480                 rc = -E2BIG;
 481                 goto out;
 482         }
 483
 484         memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
 485         payload->blob_len = blob_len;
 486
 487 out:
 488         tpm_buf_destroy(&buf);
 489
 490         if (rc > 0)
 491                 rc = -EPERM;
 492
 493         return rc;
 494 }
 495
 496 static int tpm2_load(struct tpm_chip *chip,
 497                      struct trusted_key_payload *payload,
 498                      struct trusted_key_options *options,
 499                      u32 *blob_handle)
 500 {
 501         struct tpm_buf buf;
 502         unsigned int private_len;
 503         unsigned int public_len;
 504         unsigned int blob_len;
 505         int rc;
 506
 507         private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
 508         if (private_len > (payload->blob_len - 2))
 509                 return -E2BIG;
 510
 511         public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
 512         blob_len = private_len + public_len + 4;
 513         if (blob_len > payload->blob_len)
 514                 return -E2BIG;
 515
 516         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
 517         if (rc)
 518                 return rc;
 519
 520         tpm_buf_append_u32(&buf, options->keyhandle);
 521         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 522                              NULL /* nonce */, 0,
 523                              0 /* session_attributes */,
 524                              options->keyauth /* hmac */,
 525                              TPM_DIGEST_SIZE);
 526
 527         tpm_buf_append(&buf, payload->blob, blob_len);
 528
 529         if (buf.flags & TPM_BUF_OVERFLOW) {
 530                 rc = -E2BIG;
 531                 goto out;
 532         }
 533
 534         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "loading blob");
 535         if (!rc)
 536                 *blob_handle = be32_to_cpup(
 537                         (__be32 *) &buf.data[TPM_HEADER_SIZE]);
 538
 539 out:
 540         tpm_buf_destroy(&buf);
 541
 542         if (rc > 0)
 543                 rc = -EPERM;
 544
 545         return rc;
 546 }
 547
 548 static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
 549 {
 550         struct tpm_buf buf;
 551         int rc;
 552
 553         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
 554         if (rc) {
 555                 dev_warn(chip->pdev, "0x%08x was not flushed, out of memory\n",
 556                          handle);
 557                 return;
 558         }
 559
 560         tpm_buf_append_u32(&buf, handle);
 561
 562         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "flushing context");
 563         if (rc)
 564                 dev_warn(chip->pdev, "0x%08x was not flushed, rc=%d\n", handle,
 565                          rc);
 566
 567         tpm_buf_destroy(&buf);
 568 }
 569
 570 static int tpm2_unseal(struct tpm_chip *chip,
 571                        struct trusted_key_payload *payload,
 572                        struct trusted_key_options *options,
 573                        u32 blob_handle)
 574 {
 575         struct tpm_buf buf;
 576         int rc;
 577
 578         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
 579         if (rc)
 580                 return rc;
 581
 582         tpm_buf_append_u32(&buf, blob_handle);
 583         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 584                              NULL /* nonce */, 0,
 585                              0 /* session_attributes */,
 586                              options->blobauth /* hmac */,
 587                              TPM_DIGEST_SIZE);
 588
 589         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "unsealing");
 590         if (rc > 0)
 591                 rc = -EPERM;
 592
 593         if (!rc) {
 594                 payload->key_len = be16_to_cpup(
 595                         (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
 596
 597                 memcpy(payload->key, &buf.data[TPM_HEADER_SIZE + 6],
 598                        payload->key_len);
 599         }
 600
 601         tpm_buf_destroy(&buf);
 602         return rc;
 603 }
 604
 605 /**
 606  * tpm_unseal_trusted() - unseal a trusted key
 607  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
 608  * @options: authentication values and other options
 609  * @payload: the key data in clear and encrypted form
 610  *
 611  * Returns < 0 on error and 0 on success.
 612  */
 613 int tpm2_unseal_trusted(struct tpm_chip *chip,
 614                         struct trusted_key_payload *payload,
 615                         struct trusted_key_options *options)
 616 {
 617         u32 blob_handle;
 618         int rc;
 619
 620         rc = tpm2_load(chip, payload, options, &blob_handle);
 621         if (rc)
 622                 return rc;
 623
 624         rc = tpm2_unseal(chip, payload, options, blob_handle);
 625
 626         tpm2_flush_context(chip, blob_handle);
 627
 628         return rc;
 629 }
 630
 631 /**
 632  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
 633  * @chip:               TPM chip to use.
 634  * @property_id:        property ID.
 635  * @value:              output variable.
 636  * @desc:               passed to tpm_transmit_cmd()
 637  *
 638  * 0 is returned when the operation is successful. If a negative number is
 639  * returned it remarks a POSIX error code. If a positive number is returned
 640  * it remarks a TPM error.
 641  */
 642 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 643                         const char *desc)
 644 {
 645         struct tpm2_cmd cmd;
 646         int rc;
 647
 648         cmd.header.in = tpm2_get_tpm_pt_header;
 649         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
 650         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
 651         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 652
 653         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), desc);
 654         if (!rc)
 655                 *value = cmd.params.get_tpm_pt_out.value;
 656
 657         return rc;
 658 }
 659
 660 #define TPM2_STARTUP_IN_SIZE \
 661         (sizeof(struct tpm_input_header) + \
 662          sizeof(struct tpm2_startup_in))
 663
 664 static const struct tpm_input_header tpm2_startup_header = {
 665         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 666         .length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
 667         .ordinal = cpu_to_be32(TPM2_CC_STARTUP)
 668 };
 669
 670 /**
 671  * tpm2_startup() - send startup command to the TPM chip
 672  * @chip:               TPM chip to use.
 673  * @startup_type        startup type. The value is either
 674  *                      TPM_SU_CLEAR or TPM_SU_STATE.
 675  *
 676  * 0 is returned when the operation is successful. If a negative number is
 677  * returned it remarks a POSIX error code. If a positive number is returned
 678  * it remarks a TPM error.
 679  */
 680 int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 681 {
 682         struct tpm2_cmd cmd;
 683
 684         cmd.header.in = tpm2_startup_header;
 685
 686         cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
 687         return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 688                                 "attempting to start the TPM");
 689 }
 690 EXPORT_SYMBOL_GPL(tpm2_startup);
 691
 692 #define TPM2_SHUTDOWN_IN_SIZE \
 693         (sizeof(struct tpm_input_header) + \
 694          sizeof(struct tpm2_startup_in))
 695
 696 static const struct tpm_input_header tpm2_shutdown_header = {
 697         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 698         .length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
 699         .ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
 700 };
 701
 702 /**
 703  * tpm2_shutdown() - send shutdown command to the TPM chip
 704  * @chip:               TPM chip to use.
 705  * @shutdown_type       shutdown type. The value is either
 706  *                      TPM_SU_CLEAR or TPM_SU_STATE.
 707  */
 708 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
 709 {
 710         struct tpm2_cmd cmd;
 711         int rc;
 712
 713         cmd.header.in = tpm2_shutdown_header;
 714         cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
 715
 716         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), "stopping the TPM");
 717
 718         /* In places where shutdown command is sent there's no much we can do
 719          * except print the error code on a system failure.
 720          */
 721         if (rc < 0)
 722                 dev_warn(chip->pdev, "transmit returned %d while stopping the TPM",
 723                          rc);
 724 }
 725 EXPORT_SYMBOL_GPL(tpm2_shutdown);
 726
 727 /*
 728  * tpm2_calc_ordinal_duration() - maximum duration for a command
 729  * @chip:       TPM chip to use.
 730  * @ordinal:    command code number.
 731  *
 732  * 0 is returned when the operation is successful. If a negative number is
 733  * returned it remarks a POSIX error code. If a positive number is returned
 734  * it remarks a TPM error.
 735  */
 736 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
 737 {
 738         int index = TPM_UNDEFINED;
 739         int duration = 0;
 740
 741         if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
 742                 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
 743
 744         if (index != TPM_UNDEFINED)
 745                 duration = chip->vendor.duration[index];
 746
 747         if (duration <= 0)
 748                 duration = 2 * 60 * HZ;
 749
 750         return duration;
 751 }
 752 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
 753
 754 #define TPM2_SELF_TEST_IN_SIZE \
 755         (sizeof(struct tpm_input_header) + \
 756          sizeof(struct tpm2_self_test_in))
 757
 758 static const struct tpm_input_header tpm2_selftest_header = {
 759         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 760         .length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
 761         .ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
 762 };
 763
 764 /**
 765  * tpm2_continue_selftest() - start a self test
 766  * @chip: TPM chip to use
 767  * @full: test all commands instead of testing only those that were not
 768  *        previously tested.
 769  *
 770  * 0 is returned when the operation is successful. If a negative number is
 771  * returned it remarks a POSIX error code. If a positive number is returned
 772  * it remarks a TPM error.
 773  */
 774 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
 775 {
 776         int rc;
 777         struct tpm2_cmd cmd;
 778
 779         cmd.header.in = tpm2_selftest_header;
 780         cmd.params.selftest_in.full_test = full;
 781
 782         rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE,
 783                               "continue selftest");
 784
 785         /* At least some prototype chips seem to give RC_TESTING error
 786          * immediately. This is a workaround for that.
 787          */
 788         if (rc == TPM2_RC_TESTING) {
 789                 dev_warn(chip->pdev, "Got RC_TESTING, ignoring\n");
 790                 rc = 0;
 791         }
 792
 793         return rc;
 794 }
 795
 796 /**
 797  * tpm2_do_selftest() - run a full self test
 798  * @chip: TPM chip to use
 799  *
 800  * During the self test TPM2 commands return with the error code RC_TESTING.
 801  * Waiting is done by issuing PCR read until it executes successfully.
 802  *
 803  * 0 is returned when the operation is successful. If a negative number is
 804  * returned it remarks a POSIX error code. If a positive number is returned
 805  * it remarks a TPM error.
 806  */
 807 int tpm2_do_selftest(struct tpm_chip *chip)
 808 {
 809         int rc;
 810         unsigned int loops;
 811         unsigned int delay_msec = 100;
 812         unsigned long duration;
 813         struct tpm2_cmd cmd;
 814         int i;
 815
 816         duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
 817
 818         loops = jiffies_to_msecs(duration) / delay_msec;
 819
 820         rc = tpm2_start_selftest(chip, true);
 821         if (rc)
 822                 return rc;
 823
 824         for (i = 0; i < loops; i++) {
 825                 /* Attempt to read a PCR value */
 826                 cmd.header.in = tpm2_pcrread_header;
 827                 cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
 828                 cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 829                 cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
 830                 cmd.params.pcrread_in.pcr_select[0] = 0x01;
 831                 cmd.params.pcrread_in.pcr_select[1] = 0x00;
 832                 cmd.params.pcrread_in.pcr_select[2] = 0x00;
 833
 834                 rc = tpm_transmit_cmd(chip, (u8 *) &cmd, sizeof(cmd), NULL);
 835                 if (rc < 0)
 836                         break;
 837
 838                 rc = be32_to_cpu(cmd.header.out.return_code);
 839                 if (rc != TPM2_RC_TESTING)
 840                         break;
 841
 842                 msleep(delay_msec);
 843         }
 844
 845         return rc;
 846 }
 847 EXPORT_SYMBOL_GPL(tpm2_do_selftest);
 848
 849 /**
 850  * tpm2_gen_interrupt() - generate an interrupt
 851  * @chip: TPM chip to use
 852  *
 853  * 0 is returned when the operation is successful. If a negative number is
 854  * returned it remarks a POSIX error code. If a positive number is returned
 855  * it remarks a TPM error.
 856  */
 857 int tpm2_gen_interrupt(struct tpm_chip *chip)
 858 {
 859         u32 dummy;
 860
 861         return tpm2_get_tpm_pt(chip, 0x100, &dummy,
 862                                "attempting to generate an interrupt");
 863 }
 864 EXPORT_SYMBOL_GPL(tpm2_gen_interrupt);
 865
 866 /**
 867  * tpm2_probe() - probe TPM 2.0
 868  * @chip: TPM chip to use
 869  *
 870  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
 871  * the reply tag.
 872  */
 873 int tpm2_probe(struct tpm_chip *chip)
 874 {
 875         struct tpm2_cmd cmd;
 876         int rc;
 877
 878         cmd.header.in = tpm2_get_tpm_pt_header;
 879         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
 880         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
 881         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 882
 883         rc = tpm_transmit(chip, (const char *) &cmd, sizeof(cmd));
 884         if (rc <  0)
 885                 return rc;
 886         else if (rc < TPM_HEADER_SIZE)
 887                 return -EFAULT;
 888
 889         if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
 890                 chip->flags |= TPM_CHIP_FLAG_TPM2;
 891
 892         return 0;
 893 }
 894 EXPORT_SYMBOL_GPL(tpm2_probe);