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 <crypto/hash_info.h>
  20 #include <keys/trusted-type.h>
  21
  22 enum tpm2_object_attributes {
  23         TPM2_ATTR_USER_WITH_AUTH        = BIT(6),
  24 };
  25
  26 struct tpm2_startup_in {
  27         __be16  startup_type;
  28 } __packed;
  29
  30 struct tpm2_self_test_in {
  31         u8      full_test;
  32 } __packed;
  33
  34 struct tpm2_pcr_read_in {
  35         __be32  pcr_selects_cnt;
  36         __be16  hash_alg;
  37         u8      pcr_select_size;
  38         u8      pcr_select[TPM2_PCR_SELECT_MIN];
  39 } __packed;
  40
  41 struct tpm2_pcr_read_out {
  42         __be32  update_cnt;
  43         __be32  pcr_selects_cnt;
  44         __be16  hash_alg;
  45         u8      pcr_select_size;
  46         u8      pcr_select[TPM2_PCR_SELECT_MIN];
  47         __be32  digests_cnt;
  48         __be16  digest_size;
  49         u8      digest[TPM_DIGEST_SIZE];
  50 } __packed;
  51
  52 struct tpm2_null_auth_area {
  53         __be32                  handle;
  54         __be16                  nonce_size;
  55         u8                      attributes;
  56         __be16                  auth_size;
  57 } __packed;
  58
  59 struct tpm2_pcr_extend_in {
  60         __be32                          pcr_idx;
  61         __be32                          auth_area_size;
  62         struct tpm2_null_auth_area      auth_area;
  63         __be32                          digest_cnt;
  64         __be16                          hash_alg;
  65         u8                              digest[TPM_DIGEST_SIZE];
  66 } __packed;
  67
  68 struct tpm2_get_tpm_pt_in {
  69         __be32  cap_id;
  70         __be32  property_id;
  71         __be32  property_cnt;
  72 } __packed;
  73
  74 struct tpm2_get_tpm_pt_out {
  75         u8      more_data;
  76         __be32  subcap_id;
  77         __be32  property_cnt;
  78         __be32  property_id;
  79         __be32  value;
  80 } __packed;
  81
  82 struct tpm2_get_random_in {
  83         __be16  size;
  84 } __packed;
  85
  86 struct tpm2_get_random_out {
  87         __be16  size;
  88         u8      buffer[TPM_MAX_RNG_DATA];
  89 } __packed;
  90
  91 union tpm2_cmd_params {
  92         struct  tpm2_startup_in         startup_in;
  93         struct  tpm2_self_test_in       selftest_in;
  94         struct  tpm2_pcr_read_in        pcrread_in;
  95         struct  tpm2_pcr_read_out       pcrread_out;
  96         struct  tpm2_pcr_extend_in      pcrextend_in;
  97         struct  tpm2_get_tpm_pt_in      get_tpm_pt_in;
  98         struct  tpm2_get_tpm_pt_out     get_tpm_pt_out;
  99         struct  tpm2_get_random_in      getrandom_in;
 100         struct  tpm2_get_random_out     getrandom_out;
 101 };
 102
 103 struct tpm2_cmd {
 104         tpm_cmd_header          header;
 105         union tpm2_cmd_params   params;
 106 } __packed;
 107
 108 struct tpm2_hash {
 109         unsigned int crypto_id;
 110         unsigned int tpm_id;
 111 };
 112
 113 static struct tpm2_hash tpm2_hash_map[] = {
 114         {HASH_ALGO_SHA1, TPM2_ALG_SHA1},
 115         {HASH_ALGO_SHA256, TPM2_ALG_SHA256},
 116         {HASH_ALGO_SHA384, TPM2_ALG_SHA384},
 117         {HASH_ALGO_SHA512, TPM2_ALG_SHA512},
 118         {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
 119 };
 120
 121 /*
 122  * Array with one entry per ordinal defining the maximum amount
 123  * of time the chip could take to return the result. The values
 124  * of the SHORT, MEDIUM, and LONG durations are taken from the
 125  * PC Client Profile (PTP) specification.
 126  */
 127 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
 128         TPM_UNDEFINED,          /* 11F */
 129         TPM_UNDEFINED,          /* 120 */
 130         TPM_LONG,               /* 121 */
 131         TPM_UNDEFINED,          /* 122 */
 132         TPM_UNDEFINED,          /* 123 */
 133         TPM_UNDEFINED,          /* 124 */
 134         TPM_UNDEFINED,          /* 125 */
 135         TPM_UNDEFINED,          /* 126 */
 136         TPM_UNDEFINED,          /* 127 */
 137         TPM_UNDEFINED,          /* 128 */
 138         TPM_LONG,               /* 129 */
 139         TPM_UNDEFINED,          /* 12a */
 140         TPM_UNDEFINED,          /* 12b */
 141         TPM_UNDEFINED,          /* 12c */
 142         TPM_UNDEFINED,          /* 12d */
 143         TPM_UNDEFINED,          /* 12e */
 144         TPM_UNDEFINED,          /* 12f */
 145         TPM_UNDEFINED,          /* 130 */
 146         TPM_UNDEFINED,          /* 131 */
 147         TPM_UNDEFINED,          /* 132 */
 148         TPM_UNDEFINED,          /* 133 */
 149         TPM_UNDEFINED,          /* 134 */
 150         TPM_UNDEFINED,          /* 135 */
 151         TPM_UNDEFINED,          /* 136 */
 152         TPM_UNDEFINED,          /* 137 */
 153         TPM_UNDEFINED,          /* 138 */
 154         TPM_UNDEFINED,          /* 139 */
 155         TPM_UNDEFINED,          /* 13a */
 156         TPM_UNDEFINED,          /* 13b */
 157         TPM_UNDEFINED,          /* 13c */
 158         TPM_UNDEFINED,          /* 13d */
 159         TPM_MEDIUM,             /* 13e */
 160         TPM_UNDEFINED,          /* 13f */
 161         TPM_UNDEFINED,          /* 140 */
 162         TPM_UNDEFINED,          /* 141 */
 163         TPM_UNDEFINED,          /* 142 */
 164         TPM_LONG,               /* 143 */
 165         TPM_MEDIUM,             /* 144 */
 166         TPM_UNDEFINED,          /* 145 */
 167         TPM_UNDEFINED,          /* 146 */
 168         TPM_UNDEFINED,          /* 147 */
 169         TPM_UNDEFINED,          /* 148 */
 170         TPM_UNDEFINED,          /* 149 */
 171         TPM_UNDEFINED,          /* 14a */
 172         TPM_UNDEFINED,          /* 14b */
 173         TPM_UNDEFINED,          /* 14c */
 174         TPM_UNDEFINED,          /* 14d */
 175         TPM_LONG,               /* 14e */
 176         TPM_UNDEFINED,          /* 14f */
 177         TPM_UNDEFINED,          /* 150 */
 178         TPM_UNDEFINED,          /* 151 */
 179         TPM_UNDEFINED,          /* 152 */
 180         TPM_UNDEFINED,          /* 153 */
 181         TPM_UNDEFINED,          /* 154 */
 182         TPM_UNDEFINED,          /* 155 */
 183         TPM_UNDEFINED,          /* 156 */
 184         TPM_UNDEFINED,          /* 157 */
 185         TPM_UNDEFINED,          /* 158 */
 186         TPM_UNDEFINED,          /* 159 */
 187         TPM_UNDEFINED,          /* 15a */
 188         TPM_UNDEFINED,          /* 15b */
 189         TPM_MEDIUM,             /* 15c */
 190         TPM_UNDEFINED,          /* 15d */
 191         TPM_UNDEFINED,          /* 15e */
 192         TPM_UNDEFINED,          /* 15f */
 193         TPM_UNDEFINED,          /* 160 */
 194         TPM_UNDEFINED,          /* 161 */
 195         TPM_UNDEFINED,          /* 162 */
 196         TPM_UNDEFINED,          /* 163 */
 197         TPM_UNDEFINED,          /* 164 */
 198         TPM_UNDEFINED,          /* 165 */
 199         TPM_UNDEFINED,          /* 166 */
 200         TPM_UNDEFINED,          /* 167 */
 201         TPM_UNDEFINED,          /* 168 */
 202         TPM_UNDEFINED,          /* 169 */
 203         TPM_UNDEFINED,          /* 16a */
 204         TPM_UNDEFINED,          /* 16b */
 205         TPM_UNDEFINED,          /* 16c */
 206         TPM_UNDEFINED,          /* 16d */
 207         TPM_UNDEFINED,          /* 16e */
 208         TPM_UNDEFINED,          /* 16f */
 209         TPM_UNDEFINED,          /* 170 */
 210         TPM_UNDEFINED,          /* 171 */
 211         TPM_UNDEFINED,          /* 172 */
 212         TPM_UNDEFINED,          /* 173 */
 213         TPM_UNDEFINED,          /* 174 */
 214         TPM_UNDEFINED,          /* 175 */
 215         TPM_UNDEFINED,          /* 176 */
 216         TPM_LONG,               /* 177 */
 217         TPM_UNDEFINED,          /* 178 */
 218         TPM_UNDEFINED,          /* 179 */
 219         TPM_MEDIUM,             /* 17a */
 220         TPM_LONG,               /* 17b */
 221         TPM_UNDEFINED,          /* 17c */
 222         TPM_UNDEFINED,          /* 17d */
 223         TPM_UNDEFINED,          /* 17e */
 224         TPM_UNDEFINED,          /* 17f */
 225         TPM_UNDEFINED,          /* 180 */
 226         TPM_UNDEFINED,          /* 181 */
 227         TPM_MEDIUM,             /* 182 */
 228         TPM_UNDEFINED,          /* 183 */
 229         TPM_UNDEFINED,          /* 184 */
 230         TPM_MEDIUM,             /* 185 */
 231         TPM_MEDIUM,             /* 186 */
 232         TPM_UNDEFINED,          /* 187 */
 233         TPM_UNDEFINED,          /* 188 */
 234         TPM_UNDEFINED,          /* 189 */
 235         TPM_UNDEFINED,          /* 18a */
 236         TPM_UNDEFINED,          /* 18b */
 237         TPM_UNDEFINED,          /* 18c */
 238         TPM_UNDEFINED,          /* 18d */
 239         TPM_UNDEFINED,          /* 18e */
 240         TPM_UNDEFINED           /* 18f */
 241 };
 242
 243 #define TPM2_PCR_READ_IN_SIZE \
 244         (sizeof(struct tpm_input_header) + \
 245          sizeof(struct tpm2_pcr_read_in))
 246
 247 static const struct tpm_input_header tpm2_pcrread_header = {
 248         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 249         .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
 250         .ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
 251 };
 252
 253 /**
 254  * tpm2_pcr_read() - read a PCR value
 255  * @chip:       TPM chip to use.
 256  * @pcr_idx:    index of the PCR to read.
 257  * @ref_buf:    buffer to store the resulting hash,
 258  *
 259  * 0 is returned when the operation is successful. If a negative number is
 260  * returned it remarks a POSIX error code. If a positive number is returned
 261  * it remarks a TPM error.
 262  */
 263 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 264 {
 265         int rc;
 266         struct tpm2_cmd cmd;
 267         u8 *buf;
 268
 269         if (pcr_idx >= TPM2_PLATFORM_PCR)
 270                 return -EINVAL;
 271
 272         cmd.header.in = tpm2_pcrread_header;
 273         cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
 274         cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 275         cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
 276
 277         memset(cmd.params.pcrread_in.pcr_select, 0,
 278                sizeof(cmd.params.pcrread_in.pcr_select));
 279         cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
 280
 281         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 282                               "attempting to read a pcr value");
 283         if (rc == 0) {
 284                 buf = cmd.params.pcrread_out.digest;
 285                 memcpy(res_buf, buf, TPM_DIGEST_SIZE);
 286         }
 287
 288         return rc;
 289 }
 290
 291 #define TPM2_GET_PCREXTEND_IN_SIZE \
 292         (sizeof(struct tpm_input_header) + \
 293          sizeof(struct tpm2_pcr_extend_in))
 294
 295 static const struct tpm_input_header tpm2_pcrextend_header = {
 296         .tag = cpu_to_be16(TPM2_ST_SESSIONS),
 297         .length = cpu_to_be32(TPM2_GET_PCREXTEND_IN_SIZE),
 298         .ordinal = cpu_to_be32(TPM2_CC_PCR_EXTEND)
 299 };
 300
 301 /**
 302  * tpm2_pcr_extend() - extend a PCR value
 303  * @chip:       TPM chip to use.
 304  * @pcr_idx:    index of the PCR.
 305  * @hash:       hash value to use for the extend operation.
 306  *
 307  * 0 is returned when the operation is successful. If a negative number is
 308  * returned it remarks a POSIX error code. If a positive number is returned
 309  * it remarks a TPM error.
 310  */
 311 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
 312 {
 313         struct tpm2_cmd cmd;
 314         int rc;
 315
 316         cmd.header.in = tpm2_pcrextend_header;
 317         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 318         cmd.params.pcrextend_in.auth_area_size =
 319                 cpu_to_be32(sizeof(struct tpm2_null_auth_area));
 320         cmd.params.pcrextend_in.auth_area.handle =
 321                 cpu_to_be32(TPM2_RS_PW);
 322         cmd.params.pcrextend_in.auth_area.nonce_size = 0;
 323         cmd.params.pcrextend_in.auth_area.attributes = 0;
 324         cmd.params.pcrextend_in.auth_area.auth_size = 0;
 325         cmd.params.pcrextend_in.digest_cnt = cpu_to_be32(1);
 326         cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 327         memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);
 328
 329         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 330                               "attempting extend a PCR value");
 331
 332         return rc;
 333 }
 334
 335 #define TPM2_GETRANDOM_IN_SIZE \
 336         (sizeof(struct tpm_input_header) + \
 337          sizeof(struct tpm2_get_random_in))
 338
 339 static const struct tpm_input_header tpm2_getrandom_header = {
 340         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 341         .length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
 342         .ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
 343 };
 344
 345 /**
 346  * tpm2_get_random() - get random bytes from the TPM RNG
 347  * @chip: TPM chip to use
 348  * @out: destination buffer for the random bytes
 349  * @max: the max number of bytes to write to @out
 350  *
 351  * 0 is returned when the operation is successful. If a negative number is
 352  * returned it remarks a POSIX error code. If a positive number is returned
 353  * it remarks a TPM error.
 354  */
 355 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
 356 {
 357         struct tpm2_cmd cmd;
 358         u32 recd;
 359         u32 num_bytes;
 360         int err;
 361         int total = 0;
 362         int retries = 5;
 363         u8 *dest = out;
 364
 365         num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
 366
 367         if (!out || !num_bytes ||
 368             max > sizeof(cmd.params.getrandom_out.buffer))
 369                 return -EINVAL;
 370
 371         do {
 372                 cmd.header.in = tpm2_getrandom_header;
 373                 cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
 374
 375                 err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 376                                        "attempting get random");
 377                 if (err)
 378                         break;
 379
 380                 recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
 381                              num_bytes);
 382                 memcpy(dest, cmd.params.getrandom_out.buffer, recd);
 383
 384                 dest += recd;
 385                 total += recd;
 386                 num_bytes -= recd;
 387         } while (retries-- && total < max);
 388
 389         return total ? total : -EIO;
 390 }
 391
 392 #define TPM2_GET_TPM_PT_IN_SIZE \
 393         (sizeof(struct tpm_input_header) + \
 394          sizeof(struct tpm2_get_tpm_pt_in))
 395
 396 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
 397         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 398         .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
 399         .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
 400 };
 401
 402 /**
 403  * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated with
 404  * tpm_buf_alloc().
 405  *
 406  * @param buf: an allocated tpm_buf instance
 407  * @param nonce: the session nonce, may be NULL if not used
 408  * @param nonce_len: the session nonce length, may be 0 if not used
 409  * @param attributes: the session attributes
 410  * @param hmac: the session HMAC or password, may be NULL if not used
 411  * @param hmac_len: the session HMAC or password length, maybe 0 if not used
 412  */
 413 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
 414                                  const u8 *nonce, u16 nonce_len,
 415                                  u8 attributes,
 416                                  const u8 *hmac, u16 hmac_len)
 417 {
 418         tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
 419         tpm_buf_append_u32(buf, session_handle);
 420         tpm_buf_append_u16(buf, nonce_len);
 421
 422         if (nonce && nonce_len)
 423                 tpm_buf_append(buf, nonce, nonce_len);
 424
 425         tpm_buf_append_u8(buf, attributes);
 426         tpm_buf_append_u16(buf, hmac_len);
 427
 428         if (hmac && hmac_len)
 429                 tpm_buf_append(buf, hmac, hmac_len);
 430 }
 431
 432 /**
 433  * tpm2_seal_trusted() - seal a trusted key
 434  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
 435  * @options: authentication values and other options
 436  * @payload: the key data in clear and encrypted form
 437  *
 438  * Returns < 0 on error and 0 on success.
 439  */
 440 int tpm2_seal_trusted(struct tpm_chip *chip,
 441                       struct trusted_key_payload *payload,
 442                       struct trusted_key_options *options)
 443 {
 444         unsigned int blob_len;
 445         struct tpm_buf buf;
 446         u32 hash;
 447         int i;
 448         int rc;
 449
 450         for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
 451                 if (options->hash == tpm2_hash_map[i].crypto_id) {
 452                         hash = tpm2_hash_map[i].tpm_id;
 453                         break;
 454                 }
 455         }
 456
 457         if (i == ARRAY_SIZE(tpm2_hash_map))
 458                 return -EINVAL;
 459
 460         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
 461         if (rc)
 462                 return rc;
 463
 464         tpm_buf_append_u32(&buf, options->keyhandle);
 465         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 466                              NULL /* nonce */, 0,
 467                              0 /* session_attributes */,
 468                              options->keyauth /* hmac */,
 469                              TPM_DIGEST_SIZE);
 470
 471         /* sensitive */
 472         tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
 473
 474         tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
 475         tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
 476         tpm_buf_append_u16(&buf, payload->key_len + 1);
 477         tpm_buf_append(&buf, payload->key, payload->key_len);
 478         tpm_buf_append_u8(&buf, payload->migratable);
 479
 480         /* public */
 481         tpm_buf_append_u16(&buf, 14);
 482
 483         tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
 484         tpm_buf_append_u16(&buf, hash);
 485         tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH);
 486         tpm_buf_append_u16(&buf, 0); /* policy digest size */
 487         tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
 488         tpm_buf_append_u16(&buf, 0);
 489
 490         /* outside info */
 491         tpm_buf_append_u16(&buf, 0);
 492
 493         /* creation PCR */
 494         tpm_buf_append_u32(&buf, 0);
 495
 496         if (buf.flags & TPM_BUF_OVERFLOW) {
 497                 rc = -E2BIG;
 498                 goto out;
 499         }
 500
 501         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "sealing data");
 502         if (rc)
 503                 goto out;
 504
 505         blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
 506         if (blob_len > MAX_BLOB_SIZE) {
 507                 rc = -E2BIG;
 508                 goto out;
 509         }
 510
 511         memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
 512         payload->blob_len = blob_len;
 513
 514 out:
 515         tpm_buf_destroy(&buf);
 516
 517         if (rc > 0) {
 518                 if ((rc & TPM2_RC_HASH) == TPM2_RC_HASH)
 519                         rc = -EINVAL;
 520                 else
 521                         rc = -EPERM;
 522         }
 523
 524         return rc;
 525 }
 526
 527 static int tpm2_load(struct tpm_chip *chip,
 528                      struct trusted_key_payload *payload,
 529                      struct trusted_key_options *options,
 530                      u32 *blob_handle)
 531 {
 532         struct tpm_buf buf;
 533         unsigned int private_len;
 534         unsigned int public_len;
 535         unsigned int blob_len;
 536         int rc;
 537
 538         private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
 539         if (private_len > (payload->blob_len - 2))
 540                 return -E2BIG;
 541
 542         public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
 543         blob_len = private_len + public_len + 4;
 544         if (blob_len > payload->blob_len)
 545                 return -E2BIG;
 546
 547         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
 548         if (rc)
 549                 return rc;
 550
 551         tpm_buf_append_u32(&buf, options->keyhandle);
 552         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 553                              NULL /* nonce */, 0,
 554                              0 /* session_attributes */,
 555                              options->keyauth /* hmac */,
 556                              TPM_DIGEST_SIZE);
 557
 558         tpm_buf_append(&buf, payload->blob, blob_len);
 559
 560         if (buf.flags & TPM_BUF_OVERFLOW) {
 561                 rc = -E2BIG;
 562                 goto out;
 563         }
 564
 565         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "loading blob");
 566         if (!rc)
 567                 *blob_handle = be32_to_cpup(
 568                         (__be32 *) &buf.data[TPM_HEADER_SIZE]);
 569
 570 out:
 571         tpm_buf_destroy(&buf);
 572
 573         if (rc > 0)
 574                 rc = -EPERM;
 575
 576         return rc;
 577 }
 578
 579 static void tpm2_flush_context(struct tpm_chip *chip, u32 handle)
 580 {
 581         struct tpm_buf buf;
 582         int rc;
 583
 584         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
 585         if (rc) {
 586                 dev_warn(chip->pdev, "0x%08x was not flushed, out of memory\n",
 587                          handle);
 588                 return;
 589         }
 590
 591         tpm_buf_append_u32(&buf, handle);
 592
 593         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "flushing context");
 594         if (rc)
 595                 dev_warn(chip->pdev, "0x%08x was not flushed, rc=%d\n", handle,
 596                          rc);
 597
 598         tpm_buf_destroy(&buf);
 599 }
 600
 601 static int tpm2_unseal(struct tpm_chip *chip,
 602                        struct trusted_key_payload *payload,
 603                        struct trusted_key_options *options,
 604                        u32 blob_handle)
 605 {
 606         struct tpm_buf buf;
 607         u16 data_len;
 608         u8 *data;
 609         int rc;
 610
 611         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
 612         if (rc)
 613                 return rc;
 614
 615         tpm_buf_append_u32(&buf, blob_handle);
 616         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
 617                              NULL /* nonce */, 0,
 618                              0 /* session_attributes */,
 619                              options->blobauth /* hmac */,
 620                              TPM_DIGEST_SIZE);
 621
 622         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, "unsealing");
 623         if (rc > 0)
 624                 rc = -EPERM;
 625
 626         if (!rc) {
 627                 data_len = be16_to_cpup(
 628                         (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
 629                 data = &buf.data[TPM_HEADER_SIZE + 6];
 630
 631                 memcpy(payload->key, data, data_len - 1);
 632                 payload->key_len = data_len - 1;
 633                 payload->migratable = data[data_len - 1];
 634         }
 635
 636         tpm_buf_destroy(&buf);
 637         return rc;
 638 }
 639
 640 /**
 641  * tpm_unseal_trusted() - unseal a trusted key
 642  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
 643  * @options: authentication values and other options
 644  * @payload: the key data in clear and encrypted form
 645  *
 646  * Returns < 0 on error and 0 on success.
 647  */
 648 int tpm2_unseal_trusted(struct tpm_chip *chip,
 649                         struct trusted_key_payload *payload,
 650                         struct trusted_key_options *options)
 651 {
 652         u32 blob_handle;
 653         int rc;
 654
 655         rc = tpm2_load(chip, payload, options, &blob_handle);
 656         if (rc)
 657                 return rc;
 658
 659         rc = tpm2_unseal(chip, payload, options, blob_handle);
 660
 661         tpm2_flush_context(chip, blob_handle);
 662
 663         return rc;
 664 }
 665
 666 /**
 667  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
 668  * @chip:               TPM chip to use.
 669  * @property_id:        property ID.
 670  * @value:              output variable.
 671  * @desc:               passed to tpm_transmit_cmd()
 672  *
 673  * 0 is returned when the operation is successful. If a negative number is
 674  * returned it remarks a POSIX error code. If a positive number is returned
 675  * it remarks a TPM error.
 676  */
 677 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
 678                         const char *desc)
 679 {
 680         struct tpm2_cmd cmd;
 681         int rc;
 682
 683         cmd.header.in = tpm2_get_tpm_pt_header;
 684         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
 685         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
 686         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 687
 688         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), desc);
 689         if (!rc)
 690                 *value = cmd.params.get_tpm_pt_out.value;
 691
 692         return rc;
 693 }
 694
 695 #define TPM2_STARTUP_IN_SIZE \
 696         (sizeof(struct tpm_input_header) + \
 697          sizeof(struct tpm2_startup_in))
 698
 699 static const struct tpm_input_header tpm2_startup_header = {
 700         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 701         .length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
 702         .ordinal = cpu_to_be32(TPM2_CC_STARTUP)
 703 };
 704
 705 /**
 706  * tpm2_startup() - send startup command to the TPM chip
 707  * @chip:               TPM chip to use.
 708  * @startup_type        startup type. The value is either
 709  *                      TPM_SU_CLEAR or TPM_SU_STATE.
 710  *
 711  * 0 is returned when the operation is successful. If a negative number is
 712  * returned it remarks a POSIX error code. If a positive number is returned
 713  * it remarks a TPM error.
 714  */
 715 int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
 716 {
 717         struct tpm2_cmd cmd;
 718
 719         cmd.header.in = tpm2_startup_header;
 720
 721         cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
 722         return tpm_transmit_cmd(chip, &cmd, sizeof(cmd),
 723                                 "attempting to start the TPM");
 724 }
 725 EXPORT_SYMBOL_GPL(tpm2_startup);
 726
 727 #define TPM2_SHUTDOWN_IN_SIZE \
 728         (sizeof(struct tpm_input_header) + \
 729          sizeof(struct tpm2_startup_in))
 730
 731 static const struct tpm_input_header tpm2_shutdown_header = {
 732         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 733         .length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
 734         .ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
 735 };
 736
 737 /**
 738  * tpm2_shutdown() - send shutdown command to the TPM chip
 739  * @chip:               TPM chip to use.
 740  * @shutdown_type       shutdown type. The value is either
 741  *                      TPM_SU_CLEAR or TPM_SU_STATE.
 742  */
 743 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
 744 {
 745         struct tpm2_cmd cmd;
 746         int rc;
 747
 748         cmd.header.in = tpm2_shutdown_header;
 749         cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
 750
 751         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), "stopping the TPM");
 752
 753         /* In places where shutdown command is sent there's no much we can do
 754          * except print the error code on a system failure.
 755          */
 756         if (rc < 0)
 757                 dev_warn(chip->pdev, "transmit returned %d while stopping the TPM",
 758                          rc);
 759 }
 760 EXPORT_SYMBOL_GPL(tpm2_shutdown);
 761
 762 /*
 763  * tpm2_calc_ordinal_duration() - maximum duration for a command
 764  * @chip:       TPM chip to use.
 765  * @ordinal:    command code number.
 766  *
 767  * 0 is returned when the operation is successful. If a negative number is
 768  * returned it remarks a POSIX error code. If a positive number is returned
 769  * it remarks a TPM error.
 770  */
 771 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
 772 {
 773         int index = TPM_UNDEFINED;
 774         int duration = 0;
 775
 776         if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
 777                 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
 778
 779         if (index != TPM_UNDEFINED)
 780                 duration = chip->vendor.duration[index];
 781
 782         if (duration <= 0)
 783                 duration = 2 * 60 * HZ;
 784
 785         return duration;
 786 }
 787 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
 788
 789 #define TPM2_SELF_TEST_IN_SIZE \
 790         (sizeof(struct tpm_input_header) + \
 791          sizeof(struct tpm2_self_test_in))
 792
 793 static const struct tpm_input_header tpm2_selftest_header = {
 794         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
 795         .length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
 796         .ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
 797 };
 798
 799 /**
 800  * tpm2_continue_selftest() - start a self test
 801  * @chip: TPM chip to use
 802  * @full: test all commands instead of testing only those that were not
 803  *        previously tested.
 804  *
 805  * 0 is returned when the operation is successful. If a negative number is
 806  * returned it remarks a POSIX error code. If a positive number is returned
 807  * it remarks a TPM error.
 808  */
 809 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
 810 {
 811         int rc;
 812         struct tpm2_cmd cmd;
 813
 814         cmd.header.in = tpm2_selftest_header;
 815         cmd.params.selftest_in.full_test = full;
 816
 817         rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE,
 818                               "continue selftest");
 819
 820         /* At least some prototype chips seem to give RC_TESTING error
 821          * immediately. This is a workaround for that.
 822          */
 823         if (rc == TPM2_RC_TESTING) {
 824                 dev_warn(chip->pdev, "Got RC_TESTING, ignoring\n");
 825                 rc = 0;
 826         }
 827
 828         return rc;
 829 }
 830
 831 /**
 832  * tpm2_do_selftest() - run a full self test
 833  * @chip: TPM chip to use
 834  *
 835  * During the self test TPM2 commands return with the error code RC_TESTING.
 836  * Waiting is done by issuing PCR read until it executes successfully.
 837  *
 838  * 0 is returned when the operation is successful. If a negative number is
 839  * returned it remarks a POSIX error code. If a positive number is returned
 840  * it remarks a TPM error.
 841  */
 842 int tpm2_do_selftest(struct tpm_chip *chip)
 843 {
 844         int rc;
 845         unsigned int loops;
 846         unsigned int delay_msec = 100;
 847         unsigned long duration;
 848         struct tpm2_cmd cmd;
 849         int i;
 850
 851         duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
 852
 853         loops = jiffies_to_msecs(duration) / delay_msec;
 854
 855         rc = tpm2_start_selftest(chip, true);
 856         if (rc)
 857                 return rc;
 858
 859         for (i = 0; i < loops; i++) {
 860                 /* Attempt to read a PCR value */
 861                 cmd.header.in = tpm2_pcrread_header;
 862                 cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
 863                 cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
 864                 cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
 865                 cmd.params.pcrread_in.pcr_select[0] = 0x01;
 866                 cmd.params.pcrread_in.pcr_select[1] = 0x00;
 867                 cmd.params.pcrread_in.pcr_select[2] = 0x00;
 868
 869                 rc = tpm_transmit_cmd(chip, (u8 *) &cmd, sizeof(cmd), NULL);
 870                 if (rc < 0)
 871                         break;
 872
 873                 rc = be32_to_cpu(cmd.header.out.return_code);
 874                 if (rc != TPM2_RC_TESTING)
 875                         break;
 876
 877                 msleep(delay_msec);
 878         }
 879
 880         return rc;
 881 }
 882 EXPORT_SYMBOL_GPL(tpm2_do_selftest);
 883
 884 /**
 885  * tpm2_gen_interrupt() - generate an interrupt
 886  * @chip: TPM chip to use
 887  *
 888  * 0 is returned when the operation is successful. If a negative number is
 889  * returned it remarks a POSIX error code. If a positive number is returned
 890  * it remarks a TPM error.
 891  */
 892 int tpm2_gen_interrupt(struct tpm_chip *chip)
 893 {
 894         u32 dummy;
 895
 896         return tpm2_get_tpm_pt(chip, 0x100, &dummy,
 897                                "attempting to generate an interrupt");
 898 }
 899 EXPORT_SYMBOL_GPL(tpm2_gen_interrupt);
 900
 901 /**
 902  * tpm2_probe() - probe TPM 2.0
 903  * @chip: TPM chip to use
 904  *
 905  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
 906  * the reply tag.
 907  */
 908 int tpm2_probe(struct tpm_chip *chip)
 909 {
 910         struct tpm2_cmd cmd;
 911         int rc;
 912
 913         cmd.header.in = tpm2_get_tpm_pt_header;
 914         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
 915         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
 916         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
 917
 918         rc = tpm_transmit(chip, (const char *) &cmd, sizeof(cmd));
 919         if (rc <  0)
 920                 return rc;
 921         else if (rc < TPM_HEADER_SIZE)
 922                 return -EFAULT;
 923
 924         if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
 925                 chip->flags |= TPM_CHIP_FLAG_TPM2;
 926
 927         return 0;
 928 }
 929 EXPORT_SYMBOL_GPL(tpm2_probe);