backends/tpm/tpm_emulator.c

   1 /*
   2  *  Emulator TPM driver
   3  *
   4  *  Copyright (c) 2017 Intel Corporation
   5  *  Author: Amarnath Valluri <amarnath.valluri@intel.com>
   6  *
   7  *  Copyright (c) 2010 - 2013, 2018 IBM Corporation
   8  *  Authors:
   9  *    Stefan Berger <stefanb@us.ibm.com>
  10  *
  11  *  Copyright (C) 2011 IAIK, Graz University of Technology
  12  *    Author: Andreas Niederl
  13  *
  14  * This library is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU Lesser General Public
  16  * License as published by the Free Software Foundation; either
  17  * version 2.1 of the License, or (at your option) any later version.
  18  *
  19  * This library is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  22  * Lesser General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Lesser General Public
  25  * License along with this library; if not, see <http://www.gnu.org/licenses/>
  26  *
  27  */
  28
  29 #include "qemu/osdep.h"
  30 #include "qemu/error-report.h"
  31 #include "qemu/module.h"
  32 #include "qemu/sockets.h"
  33 #include "qemu/lockable.h"
  34 #include "io/channel-socket.h"
  35 #include "sysemu/runstate.h"
  36 #include "sysemu/tpm_backend.h"
  37 #include "sysemu/tpm_util.h"
  38 #include "tpm_int.h"
  39 #include "tpm_ioctl.h"
  40 #include "migration/blocker.h"
  41 #include "migration/vmstate.h"
  42 #include "qapi/error.h"
  43 #include "qapi/clone-visitor.h"
  44 #include "qapi/qapi-visit-tpm.h"
  45 #include "chardev/char-fe.h"
  46 #include "trace.h"
  47 #include "qom/object.h"
  48
  49 #define TYPE_TPM_EMULATOR "tpm-emulator"
  50 OBJECT_DECLARE_SIMPLE_TYPE(TPMEmulator, TPM_EMULATOR)
  51
  52 #define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
  53
  54 /* data structures */
  55
  56 /* blobs from the TPM; part of VM state when migrating */
  57 typedef struct TPMBlobBuffers {
  58     uint32_t permanent_flags;
  59     TPMSizedBuffer permanent;
  60
  61     uint32_t volatil_flags;
  62     TPMSizedBuffer volatil;
  63
  64     uint32_t savestate_flags;
  65     TPMSizedBuffer savestate;
  66 } TPMBlobBuffers;
  67
  68 struct TPMEmulator {
  69     TPMBackend parent;
  70
  71     TPMEmulatorOptions *options;
  72     CharBackend ctrl_chr;
  73     QIOChannel *data_ioc;
  74     TPMVersion tpm_version;
  75     ptm_cap caps; /* capabilities of the TPM */
  76     uint8_t cur_locty_number; /* last set locality */
  77     Error *migration_blocker;
  78
  79     QemuMutex mutex;
  80
  81     unsigned int established_flag:1;
  82     unsigned int established_flag_cached:1;
  83
  84     TPMBlobBuffers state_blobs;
  85
  86     bool relock_storage;
  87     VMChangeStateEntry *vmstate;
  88 };
  89
  90 struct tpm_error {
  91     uint32_t tpm_result;
  92     const char *string;
  93 };
  94
  95 static const struct tpm_error tpm_errors[] = {
  96     /* TPM 1.2 error codes */
  97     { TPM_BAD_PARAMETER   , "a parameter is bad" },
  98     { TPM_FAIL            , "operation failed" },
  99     { TPM_KEYNOTFOUND     , "key could not be found" },
 100     { TPM_BAD_PARAM_SIZE  , "bad parameter size"},
 101     { TPM_ENCRYPT_ERROR   , "encryption error" },
 102     { TPM_DECRYPT_ERROR   , "decryption error" },
 103     { TPM_BAD_KEY_PROPERTY, "bad key property" },
 104     { TPM_BAD_MODE        , "bad (encryption) mode" },
 105     { TPM_BAD_VERSION     , "bad version identifier" },
 106     { TPM_BAD_LOCALITY    , "bad locality" },
 107     /* TPM 2 error codes */
 108     { TPM_RC_FAILURE     , "operation failed" },
 109     { TPM_RC_LOCALITY    , "bad locality"     },
 110     { TPM_RC_INSUFFICIENT, "insufficient amount of data" },
 111 };
 112
 113 static const char *tpm_emulator_strerror(uint32_t tpm_result)
 114 {
 115     size_t i;
 116
 117     for (i = 0; i < ARRAY_SIZE(tpm_errors); i++) {
 118         if (tpm_errors[i].tpm_result == tpm_result) {
 119             return tpm_errors[i].string;
 120         }
 121     }
 122     return "";
 123 }
 124
 125 static int tpm_emulator_ctrlcmd(TPMEmulator *tpm, unsigned long cmd, void *msg,
 126                                 size_t msg_len_in, size_t msg_len_out)
 127 {
 128     CharBackend *dev = &tpm->ctrl_chr;
 129     uint32_t cmd_no = cpu_to_be32(cmd);
 130     ssize_t n = sizeof(uint32_t) + msg_len_in;
 131     uint8_t *buf = NULL;
 132
 133     WITH_QEMU_LOCK_GUARD(&tpm->mutex) {
 134         buf = g_alloca(n);
 135         memcpy(buf, &cmd_no, sizeof(cmd_no));
 136         memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
 137
 138         n = qemu_chr_fe_write_all(dev, buf, n);
 139         if (n <= 0) {
 140             return -1;
 141         }
 142
 143         if (msg_len_out != 0) {
 144             n = qemu_chr_fe_read_all(dev, msg, msg_len_out);
 145             if (n <= 0) {
 146                 return -1;
 147             }
 148         }
 149     }
 150
 151     return 0;
 152 }
 153
 154 static int tpm_emulator_unix_tx_bufs(TPMEmulator *tpm_emu,
 155                                      const uint8_t *in, uint32_t in_len,
 156                                      uint8_t *out, uint32_t out_len,
 157                                      bool *selftest_done,
 158                                      Error **errp)
 159 {
 160     ssize_t ret;
 161     bool is_selftest = false;
 162
 163     if (selftest_done) {
 164         *selftest_done = false;
 165         is_selftest = tpm_util_is_selftest(in, in_len);
 166     }
 167
 168     ret = qio_channel_write_all(tpm_emu->data_ioc, (char *)in, in_len, errp);
 169     if (ret != 0) {
 170         return -1;
 171     }
 172
 173     ret = qio_channel_read_all(tpm_emu->data_ioc, (char *)out,
 174               sizeof(struct tpm_resp_hdr), errp);
 175     if (ret != 0) {
 176         return -1;
 177     }
 178
 179     ret = qio_channel_read_all(tpm_emu->data_ioc,
 180               (char *)out + sizeof(struct tpm_resp_hdr),
 181               tpm_cmd_get_size(out) - sizeof(struct tpm_resp_hdr), errp);
 182     if (ret != 0) {
 183         return -1;
 184     }
 185
 186     if (is_selftest) {
 187         *selftest_done = tpm_cmd_get_errcode(out) == 0;
 188     }
 189
 190     return 0;
 191 }
 192
 193 static int tpm_emulator_set_locality(TPMEmulator *tpm_emu, uint8_t locty_number,
 194                                      Error **errp)
 195 {
 196     ptm_loc loc;
 197
 198     if (tpm_emu->cur_locty_number == locty_number) {
 199         return 0;
 200     }
 201
 202     trace_tpm_emulator_set_locality(locty_number);
 203
 204     memset(&loc, 0, sizeof(loc));
 205     loc.u.req.loc = locty_number;
 206     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_LOCALITY, &loc,
 207                              sizeof(loc), sizeof(loc)) < 0) {
 208         error_setg(errp, "tpm-emulator: could not set locality : %s",
 209                    strerror(errno));
 210         return -1;
 211     }
 212
 213     loc.u.resp.tpm_result = be32_to_cpu(loc.u.resp.tpm_result);
 214     if (loc.u.resp.tpm_result != 0) {
 215         error_setg(errp, "tpm-emulator: TPM result for set locality : 0x%x",
 216                    loc.u.resp.tpm_result);
 217         return -1;
 218     }
 219
 220     tpm_emu->cur_locty_number = locty_number;
 221
 222     return 0;
 223 }
 224
 225 static void tpm_emulator_handle_request(TPMBackend *tb, TPMBackendCmd *cmd,
 226                                         Error **errp)
 227 {
 228     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 229
 230     trace_tpm_emulator_handle_request();
 231
 232     if (tpm_emulator_set_locality(tpm_emu, cmd->locty, errp) < 0 ||
 233         tpm_emulator_unix_tx_bufs(tpm_emu, cmd->in, cmd->in_len,
 234                                   cmd->out, cmd->out_len,
 235                                   &cmd->selftest_done, errp) < 0) {
 236         tpm_util_write_fatal_error_response(cmd->out, cmd->out_len);
 237     }
 238 }
 239
 240 static int tpm_emulator_probe_caps(TPMEmulator *tpm_emu)
 241 {
 242     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_GET_CAPABILITY,
 243                              &tpm_emu->caps, 0, sizeof(tpm_emu->caps)) < 0) {
 244         error_report("tpm-emulator: probing failed : %s", strerror(errno));
 245         return -1;
 246     }
 247
 248     tpm_emu->caps = be64_to_cpu(tpm_emu->caps);
 249
 250     trace_tpm_emulator_probe_caps(tpm_emu->caps);
 251
 252     return 0;
 253 }
 254
 255 static int tpm_emulator_check_caps(TPMEmulator *tpm_emu)
 256 {
 257     ptm_cap caps = 0;
 258     const char *tpm = NULL;
 259
 260     /* check for min. required capabilities */
 261     switch (tpm_emu->tpm_version) {
 262     case TPM_VERSION_1_2:
 263         caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
 264                PTM_CAP_SET_LOCALITY | PTM_CAP_SET_DATAFD | PTM_CAP_STOP |
 265                PTM_CAP_SET_BUFFERSIZE;
 266         tpm = "1.2";
 267         break;
 268     case TPM_VERSION_2_0:
 269         caps = PTM_CAP_INIT | PTM_CAP_SHUTDOWN | PTM_CAP_GET_TPMESTABLISHED |
 270                PTM_CAP_SET_LOCALITY | PTM_CAP_RESET_TPMESTABLISHED |
 271                PTM_CAP_SET_DATAFD | PTM_CAP_STOP | PTM_CAP_SET_BUFFERSIZE;
 272         tpm = "2";
 273         break;
 274     case TPM_VERSION_UNSPEC:
 275         error_report("tpm-emulator: TPM version has not been set");
 276         return -1;
 277     }
 278
 279     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, caps)) {
 280         error_report("tpm-emulator: TPM does not implement minimum set of "
 281                      "required capabilities for TPM %s (0x%x)", tpm, (int)caps);
 282         return -1;
 283     }
 284
 285     return 0;
 286 }
 287
 288 static int tpm_emulator_stop_tpm(TPMBackend *tb)
 289 {
 290     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 291     ptm_res res;
 292
 293     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_STOP, &res, 0, sizeof(res)) < 0) {
 294         error_report("tpm-emulator: Could not stop TPM: %s",
 295                      strerror(errno));
 296         return -1;
 297     }
 298
 299     res = be32_to_cpu(res);
 300     if (res) {
 301         error_report("tpm-emulator: TPM result for CMD_STOP: 0x%x %s", res,
 302                      tpm_emulator_strerror(res));
 303         return -1;
 304     }
 305
 306     return 0;
 307 }
 308
 309 static int tpm_emulator_lock_storage(TPMEmulator *tpm_emu)
 310 {
 311     ptm_lockstorage pls;
 312
 313     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, PTM_CAP_LOCK_STORAGE)) {
 314         trace_tpm_emulator_lock_storage_cmd_not_supt();
 315         return 0;
 316     }
 317
 318     /* give failing side 300 * 10ms time to release lock */
 319     pls.u.req.retries = cpu_to_be32(300);
 320     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_LOCK_STORAGE, &pls,
 321                              sizeof(pls.u.req), sizeof(pls.u.resp)) < 0) {
 322         error_report("tpm-emulator: Could not lock storage within 3 seconds: "
 323                      "%s", strerror(errno));
 324         return -1;
 325     }
 326
 327     pls.u.resp.tpm_result = be32_to_cpu(pls.u.resp.tpm_result);
 328     if (pls.u.resp.tpm_result != 0) {
 329         error_report("tpm-emulator: TPM result for CMD_LOCK_STORAGE: 0x%x %s",
 330                      pls.u.resp.tpm_result,
 331                      tpm_emulator_strerror(pls.u.resp.tpm_result));
 332         return -1;
 333     }
 334
 335     return 0;
 336 }
 337
 338 static int tpm_emulator_set_buffer_size(TPMBackend *tb,
 339                                         size_t wanted_size,
 340                                         size_t *actual_size)
 341 {
 342     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 343     ptm_setbuffersize psbs;
 344
 345     if (tpm_emulator_stop_tpm(tb) < 0) {
 346         return -1;
 347     }
 348
 349     psbs.u.req.buffersize = cpu_to_be32(wanted_size);
 350
 351     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_BUFFERSIZE, &psbs,
 352                              sizeof(psbs.u.req), sizeof(psbs.u.resp)) < 0) {
 353         error_report("tpm-emulator: Could not set buffer size: %s",
 354                      strerror(errno));
 355         return -1;
 356     }
 357
 358     psbs.u.resp.tpm_result = be32_to_cpu(psbs.u.resp.tpm_result);
 359     if (psbs.u.resp.tpm_result != 0) {
 360         error_report("tpm-emulator: TPM result for set buffer size : 0x%x %s",
 361                      psbs.u.resp.tpm_result,
 362                      tpm_emulator_strerror(psbs.u.resp.tpm_result));
 363         return -1;
 364     }
 365
 366     if (actual_size) {
 367         *actual_size = be32_to_cpu(psbs.u.resp.buffersize);
 368     }
 369
 370     trace_tpm_emulator_set_buffer_size(
 371             be32_to_cpu(psbs.u.resp.buffersize),
 372             be32_to_cpu(psbs.u.resp.minsize),
 373             be32_to_cpu(psbs.u.resp.maxsize));
 374
 375     return 0;
 376 }
 377
 378 static int tpm_emulator_startup_tpm_resume(TPMBackend *tb, size_t buffersize,
 379                                      bool is_resume)
 380 {
 381     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 382     ptm_init init = {
 383         .u.req.init_flags = 0,
 384     };
 385     ptm_res res;
 386
 387     trace_tpm_emulator_startup_tpm_resume(is_resume, buffersize);
 388
 389     if (buffersize != 0 &&
 390         tpm_emulator_set_buffer_size(tb, buffersize, NULL) < 0) {
 391         goto err_exit;
 392     }
 393
 394     if (is_resume) {
 395         init.u.req.init_flags |= cpu_to_be32(PTM_INIT_FLAG_DELETE_VOLATILE);
 396     }
 397
 398     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_INIT, &init, sizeof(init),
 399                              sizeof(init)) < 0) {
 400         error_report("tpm-emulator: could not send INIT: %s",
 401                      strerror(errno));
 402         goto err_exit;
 403     }
 404
 405     res = be32_to_cpu(init.u.resp.tpm_result);
 406     if (res) {
 407         error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x %s", res,
 408                      tpm_emulator_strerror(res));
 409         goto err_exit;
 410     }
 411     return 0;
 412
 413 err_exit:
 414     return -1;
 415 }
 416
 417 static int tpm_emulator_startup_tpm(TPMBackend *tb, size_t buffersize)
 418 {
 419     /* TPM startup will be done from post_load hook */
 420     if (runstate_check(RUN_STATE_INMIGRATE)) {
 421         if (buffersize != 0) {
 422             return tpm_emulator_set_buffer_size(tb, buffersize, NULL);
 423         }
 424
 425         return 0;
 426     }
 427
 428     return tpm_emulator_startup_tpm_resume(tb, buffersize, false);
 429 }
 430
 431 static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
 432 {
 433     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 434     ptm_est est;
 435
 436     if (tpm_emu->established_flag_cached) {
 437         return tpm_emu->established_flag;
 438     }
 439
 440     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_GET_TPMESTABLISHED, &est,
 441                              0, sizeof(est)) < 0) {
 442         error_report("tpm-emulator: Could not get the TPM established flag: %s",
 443                      strerror(errno));
 444         return false;
 445     }
 446     trace_tpm_emulator_get_tpm_established_flag(est.u.resp.bit);
 447
 448     tpm_emu->established_flag_cached = 1;
 449     tpm_emu->established_flag = (est.u.resp.bit != 0);
 450
 451     return tpm_emu->established_flag;
 452 }
 453
 454 static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
 455                                                    uint8_t locty)
 456 {
 457     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 458     ptm_reset_est reset_est;
 459     ptm_res res;
 460
 461     /* only a TPM 2.0 will support this */
 462     if (tpm_emu->tpm_version != TPM_VERSION_2_0) {
 463         return 0;
 464     }
 465
 466     reset_est.u.req.loc = tpm_emu->cur_locty_number;
 467     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_RESET_TPMESTABLISHED,
 468                              &reset_est, sizeof(reset_est),
 469                              sizeof(reset_est)) < 0) {
 470         error_report("tpm-emulator: Could not reset the establishment bit: %s",
 471                      strerror(errno));
 472         return -1;
 473     }
 474
 475     res = be32_to_cpu(reset_est.u.resp.tpm_result);
 476     if (res) {
 477         error_report(
 478             "tpm-emulator: TPM result for rest established flag: 0x%x %s",
 479             res, tpm_emulator_strerror(res));
 480         return -1;
 481     }
 482
 483     tpm_emu->established_flag_cached = 0;
 484
 485     return 0;
 486 }
 487
 488 static void tpm_emulator_cancel_cmd(TPMBackend *tb)
 489 {
 490     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 491     ptm_res res;
 492
 493     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, PTM_CAP_CANCEL_TPM_CMD)) {
 494         trace_tpm_emulator_cancel_cmd_not_supt();
 495         return;
 496     }
 497
 498     /* FIXME: make the function non-blocking, or it may block a VCPU */
 499     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_CANCEL_TPM_CMD, &res, 0,
 500                              sizeof(res)) < 0) {
 501         error_report("tpm-emulator: Could not cancel command: %s",
 502                      strerror(errno));
 503     } else if (res != 0) {
 504         error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
 505                      be32_to_cpu(res));
 506     }
 507 }
 508
 509 static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
 510 {
 511     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 512
 513     return tpm_emu->tpm_version;
 514 }
 515
 516 static size_t tpm_emulator_get_buffer_size(TPMBackend *tb)
 517 {
 518     size_t actual_size;
 519
 520     if (tpm_emulator_set_buffer_size(tb, 0, &actual_size) < 0) {
 521         return 4096;
 522     }
 523
 524     return actual_size;
 525 }
 526
 527 static int tpm_emulator_block_migration(TPMEmulator *tpm_emu)
 528 {
 529     Error *err = NULL;
 530     ptm_cap caps = PTM_CAP_GET_STATEBLOB | PTM_CAP_SET_STATEBLOB |
 531                    PTM_CAP_STOP;
 532
 533     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, caps)) {
 534         error_setg(&tpm_emu->migration_blocker,
 535                    "Migration disabled: TPM emulator does not support "
 536                    "migration");
 537         if (migrate_add_blocker(&tpm_emu->migration_blocker, &err) < 0) {
 538             error_report_err(err);
 539             return -1;
 540         }
 541     }
 542
 543     return 0;
 544 }
 545
 546 static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_emu)
 547 {
 548     ptm_res res;
 549     Error *err = NULL;
 550     int fds[2] = { -1, -1 };
 551
 552     if (qemu_socketpair(AF_UNIX, SOCK_STREAM, 0, fds) < 0) {
 553         error_report("tpm-emulator: Failed to create socketpair");
 554         return -1;
 555     }
 556
 557     qemu_chr_fe_set_msgfds(&tpm_emu->ctrl_chr, fds + 1, 1);
 558
 559     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_DATAFD, &res, 0,
 560                              sizeof(res)) < 0 || res != 0) {
 561         error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
 562                      strerror(errno));
 563         goto err_exit;
 564     }
 565
 566     tpm_emu->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
 567     if (err) {
 568         error_prepend(&err, "tpm-emulator: Failed to create io channel: ");
 569         error_report_err(err);
 570         goto err_exit;
 571     }
 572
 573     close(fds[1]);
 574
 575     return 0;
 576
 577 err_exit:
 578     close(fds[0]);
 579     close(fds[1]);
 580     return -1;
 581 }
 582
 583 static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_emu, QemuOpts *opts)
 584 {
 585     const char *value;
 586     Error *err = NULL;
 587     Chardev *dev;
 588
 589     value = qemu_opt_get(opts, "chardev");
 590     if (!value) {
 591         error_report("tpm-emulator: parameter 'chardev' is missing");
 592         goto err;
 593     }
 594
 595     dev = qemu_chr_find(value);
 596     if (!dev) {
 597         error_report("tpm-emulator: tpm chardev '%s' not found", value);
 598         goto err;
 599     }
 600
 601     if (!qemu_chr_fe_init(&tpm_emu->ctrl_chr, dev, &err)) {
 602         error_prepend(&err, "tpm-emulator: No valid chardev found at '%s':",
 603                       value);
 604         error_report_err(err);
 605         goto err;
 606     }
 607
 608     tpm_emu->options->chardev = g_strdup(value);
 609
 610     if (tpm_emulator_prepare_data_fd(tpm_emu) < 0) {
 611         goto err;
 612     }
 613
 614     /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
 615      * by passthrough driver, which not yet using GIOChannel.
 616      */
 617     if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_emu->data_ioc)->fd,
 618                              &tpm_emu->tpm_version)) {
 619         error_report("'%s' is not emulating TPM device. Error: %s",
 620                       tpm_emu->options->chardev, strerror(errno));
 621         goto err;
 622     }
 623
 624     switch (tpm_emu->tpm_version) {
 625     case TPM_VERSION_1_2:
 626         trace_tpm_emulator_handle_device_opts_tpm12();
 627         break;
 628     case TPM_VERSION_2_0:
 629         trace_tpm_emulator_handle_device_opts_tpm2();
 630         break;
 631     default:
 632         trace_tpm_emulator_handle_device_opts_unspec();
 633     }
 634
 635     if (tpm_emulator_probe_caps(tpm_emu) ||
 636         tpm_emulator_check_caps(tpm_emu)) {
 637         goto err;
 638     }
 639
 640     return tpm_emulator_block_migration(tpm_emu);
 641
 642 err:
 643     trace_tpm_emulator_handle_device_opts_startup_error();
 644
 645     return -1;
 646 }
 647
 648 static TPMBackend *tpm_emulator_create(QemuOpts *opts)
 649 {
 650     TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
 651
 652     if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
 653         object_unref(OBJECT(tb));
 654         return NULL;
 655     }
 656
 657     return tb;
 658 }
 659
 660 static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
 661 {
 662     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 663     TpmTypeOptions *options = g_new0(TpmTypeOptions, 1);
 664
 665     options->type = TPM_TYPE_EMULATOR;
 666     options->u.emulator.data = QAPI_CLONE(TPMEmulatorOptions, tpm_emu->options);
 667
 668     return options;
 669 }
 670
 671 static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
 672     TPM_STANDARD_CMDLINE_OPTS,
 673     {
 674         .name = "chardev",
 675         .type = QEMU_OPT_STRING,
 676         .help = "Character device to use for out-of-band control messages",
 677     },
 678     { /* end of list */ },
 679 };
 680
 681 /*
 682  * Transfer a TPM state blob from the TPM into a provided buffer.
 683  *
 684  * @tpm_emu: TPMEmulator
 685  * @type: the type of blob to transfer
 686  * @tsb: the TPMSizeBuffer to fill with the blob
 687  * @flags: the flags to return to the caller
 688  */
 689 static int tpm_emulator_get_state_blob(TPMEmulator *tpm_emu,
 690                                        uint8_t type,
 691                                        TPMSizedBuffer *tsb,
 692                                        uint32_t *flags)
 693 {
 694     ptm_getstate pgs;
 695     ptm_res res;
 696     ssize_t n;
 697     uint32_t totlength, length;
 698
 699     tpm_sized_buffer_reset(tsb);
 700
 701     pgs.u.req.state_flags = cpu_to_be32(PTM_STATE_FLAG_DECRYPTED);
 702     pgs.u.req.type = cpu_to_be32(type);
 703     pgs.u.req.offset = 0;
 704
 705     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_GET_STATEBLOB,
 706                              &pgs, sizeof(pgs.u.req),
 707                              offsetof(ptm_getstate, u.resp.data)) < 0) {
 708         error_report("tpm-emulator: could not get state blob type %d : %s",
 709                      type, strerror(errno));
 710         return -1;
 711     }
 712
 713     res = be32_to_cpu(pgs.u.resp.tpm_result);
 714     if (res != 0 && (res & 0x800) == 0) {
 715         error_report("tpm-emulator: Getting the stateblob (type %d) failed "
 716                      "with a TPM error 0x%x %s", type, res,
 717                      tpm_emulator_strerror(res));
 718         return -1;
 719     }
 720
 721     totlength = be32_to_cpu(pgs.u.resp.totlength);
 722     length = be32_to_cpu(pgs.u.resp.length);
 723     if (totlength != length) {
 724         error_report("tpm-emulator: Expecting to read %u bytes "
 725                      "but would get %u", totlength, length);
 726         return -1;
 727     }
 728
 729     *flags = be32_to_cpu(pgs.u.resp.state_flags);
 730
 731     if (totlength > 0) {
 732         tsb->buffer = g_try_malloc(totlength);
 733         if (!tsb->buffer) {
 734             error_report("tpm-emulator: Out of memory allocating %u bytes",
 735                          totlength);
 736             return -1;
 737         }
 738
 739         n = qemu_chr_fe_read_all(&tpm_emu->ctrl_chr, tsb->buffer, totlength);
 740         if (n != totlength) {
 741             error_report("tpm-emulator: Could not read stateblob (type %d); "
 742                          "expected %u bytes, got %zd",
 743                          type, totlength, n);
 744             return -1;
 745         }
 746     }
 747     tsb->size = totlength;
 748
 749     trace_tpm_emulator_get_state_blob(type, tsb->size, *flags);
 750
 751     return 0;
 752 }
 753
 754 static int tpm_emulator_get_state_blobs(TPMEmulator *tpm_emu)
 755 {
 756     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
 757
 758     if (tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_PERMANENT,
 759                                     &state_blobs->permanent,
 760                                     &state_blobs->permanent_flags) < 0 ||
 761         tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_VOLATILE,
 762                                     &state_blobs->volatil,
 763                                     &state_blobs->volatil_flags) < 0 ||
 764         tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_SAVESTATE,
 765                                     &state_blobs->savestate,
 766                                     &state_blobs->savestate_flags) < 0) {
 767         goto err_exit;
 768     }
 769
 770     return 0;
 771
 772  err_exit:
 773     tpm_sized_buffer_reset(&state_blobs->volatil);
 774     tpm_sized_buffer_reset(&state_blobs->permanent);
 775     tpm_sized_buffer_reset(&state_blobs->savestate);
 776
 777     return -1;
 778 }
 779
 780 /*
 781  * Transfer a TPM state blob to the TPM emulator.
 782  *
 783  * @tpm_emu: TPMEmulator
 784  * @type: the type of TPM state blob to transfer
 785  * @tsb: TPMSizedBuffer containing the TPM state blob
 786  * @flags: Flags describing the (encryption) state of the TPM state blob
 787  */
 788 static int tpm_emulator_set_state_blob(TPMEmulator *tpm_emu,
 789                                        uint32_t type,
 790                                        TPMSizedBuffer *tsb,
 791                                        uint32_t flags)
 792 {
 793     ssize_t n;
 794     ptm_setstate pss;
 795     ptm_res tpm_result;
 796
 797     if (tsb->size == 0) {
 798         return 0;
 799     }
 800
 801     pss = (ptm_setstate) {
 802         .u.req.state_flags = cpu_to_be32(flags),
 803         .u.req.type = cpu_to_be32(type),
 804         .u.req.length = cpu_to_be32(tsb->size),
 805     };
 806
 807     /* write the header only */
 808     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_STATEBLOB, &pss,
 809                              offsetof(ptm_setstate, u.req.data), 0) < 0) {
 810         error_report("tpm-emulator: could not set state blob type %d : %s",
 811                      type, strerror(errno));
 812         return -1;
 813     }
 814
 815     /* now the body */
 816     n = qemu_chr_fe_write_all(&tpm_emu->ctrl_chr, tsb->buffer, tsb->size);
 817     if (n != tsb->size) {
 818         error_report("tpm-emulator: Writing the stateblob (type %d) "
 819                      "failed; could not write %u bytes, but only %zd",
 820                      type, tsb->size, n);
 821         return -1;
 822     }
 823
 824     /* now get the result */
 825     n = qemu_chr_fe_read_all(&tpm_emu->ctrl_chr,
 826                              (uint8_t *)&pss, sizeof(pss.u.resp));
 827     if (n != sizeof(pss.u.resp)) {
 828         error_report("tpm-emulator: Reading response from writing stateblob "
 829                      "(type %d) failed; expected %zu bytes, got %zd", type,
 830                      sizeof(pss.u.resp), n);
 831         return -1;
 832     }
 833
 834     tpm_result = be32_to_cpu(pss.u.resp.tpm_result);
 835     if (tpm_result != 0) {
 836         error_report("tpm-emulator: Setting the stateblob (type %d) failed "
 837                      "with a TPM error 0x%x %s", type, tpm_result,
 838                      tpm_emulator_strerror(tpm_result));
 839         return -1;
 840     }
 841
 842     trace_tpm_emulator_set_state_blob(type, tsb->size, flags);
 843
 844     return 0;
 845 }
 846
 847 /*
 848  * Set all the TPM state blobs.
 849  *
 850  * Returns a negative errno code in case of error.
 851  */
 852 static int tpm_emulator_set_state_blobs(TPMBackend *tb)
 853 {
 854     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 855     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
 856
 857     trace_tpm_emulator_set_state_blobs();
 858
 859     if (tpm_emulator_stop_tpm(tb) < 0) {
 860         trace_tpm_emulator_set_state_blobs_error("Could not stop TPM");
 861         return -EIO;
 862     }
 863
 864     if (tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_PERMANENT,
 865                                     &state_blobs->permanent,
 866                                     state_blobs->permanent_flags) < 0 ||
 867         tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_VOLATILE,
 868                                     &state_blobs->volatil,
 869                                     state_blobs->volatil_flags) < 0 ||
 870         tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_SAVESTATE,
 871                                     &state_blobs->savestate,
 872                                     state_blobs->savestate_flags) < 0) {
 873         return -EIO;
 874     }
 875
 876     trace_tpm_emulator_set_state_blobs_done();
 877
 878     return 0;
 879 }
 880
 881 static int tpm_emulator_pre_save(void *opaque)
 882 {
 883     TPMBackend *tb = opaque;
 884     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 885     int ret;
 886
 887     trace_tpm_emulator_pre_save();
 888
 889     tpm_backend_finish_sync(tb);
 890
 891     /* get the state blobs from the TPM */
 892     ret = tpm_emulator_get_state_blobs(tpm_emu);
 893
 894     tpm_emu->relock_storage = ret == 0;
 895
 896     return ret;
 897 }
 898
 899 static void tpm_emulator_vm_state_change(void *opaque, bool running,
 900                                          RunState state)
 901 {
 902     TPMBackend *tb = opaque;
 903     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
 904
 905     trace_tpm_emulator_vm_state_change(running, state);
 906
 907     if (!running || state != RUN_STATE_RUNNING || !tpm_emu->relock_storage) {
 908         return;
 909     }
 910
 911     /* lock storage after migration fall-back */
 912     tpm_emulator_lock_storage(tpm_emu);
 913 }
 914
 915 /*
 916  * Load the TPM state blobs into the TPM.
 917  *
 918  * Returns negative errno codes in case of error.
 919  */
 920 static int tpm_emulator_post_load(void *opaque, int version_id)
 921 {
 922     TPMBackend *tb = opaque;
 923     int ret;
 924
 925     ret = tpm_emulator_set_state_blobs(tb);
 926     if (ret < 0) {
 927         return ret;
 928     }
 929
 930     if (tpm_emulator_startup_tpm_resume(tb, 0, true) < 0) {
 931         return -EIO;
 932     }
 933
 934     return 0;
 935 }
 936
 937 static const VMStateDescription vmstate_tpm_emulator = {
 938     .name = "tpm-emulator",
 939     .version_id = 0,
 940     .pre_save = tpm_emulator_pre_save,
 941     .post_load = tpm_emulator_post_load,
 942     .fields = (VMStateField[]) {
 943         VMSTATE_UINT32(state_blobs.permanent_flags, TPMEmulator),
 944         VMSTATE_UINT32(state_blobs.permanent.size, TPMEmulator),
 945         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.permanent.buffer,
 946                                      TPMEmulator, 0, 0,
 947                                      state_blobs.permanent.size),
 948
 949         VMSTATE_UINT32(state_blobs.volatil_flags, TPMEmulator),
 950         VMSTATE_UINT32(state_blobs.volatil.size, TPMEmulator),
 951         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.volatil.buffer,
 952                                      TPMEmulator, 0, 0,
 953                                      state_blobs.volatil.size),
 954
 955         VMSTATE_UINT32(state_blobs.savestate_flags, TPMEmulator),
 956         VMSTATE_UINT32(state_blobs.savestate.size, TPMEmulator),
 957         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.savestate.buffer,
 958                                      TPMEmulator, 0, 0,
 959                                      state_blobs.savestate.size),
 960
 961         VMSTATE_END_OF_LIST()
 962     }
 963 };
 964
 965 static void tpm_emulator_inst_init(Object *obj)
 966 {
 967     TPMEmulator *tpm_emu = TPM_EMULATOR(obj);
 968
 969     trace_tpm_emulator_inst_init();
 970
 971     tpm_emu->options = g_new0(TPMEmulatorOptions, 1);
 972     tpm_emu->cur_locty_number = ~0;
 973     qemu_mutex_init(&tpm_emu->mutex);
 974     tpm_emu->vmstate =
 975         qemu_add_vm_change_state_handler(tpm_emulator_vm_state_change,
 976                                          tpm_emu);
 977
 978     vmstate_register_any(NULL, &vmstate_tpm_emulator, obj);
 979 }
 980
 981 /*
 982  * Gracefully shut down the external TPM
 983  */
 984 static void tpm_emulator_shutdown(TPMEmulator *tpm_emu)
 985 {
 986     ptm_res res;
 987
 988     if (!tpm_emu->options->chardev) {
 989         /* was never properly initialized */
 990         return;
 991     }
 992
 993     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SHUTDOWN, &res, 0, sizeof(res)) < 0) {
 994         error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
 995                      strerror(errno));
 996     } else if (res != 0) {
 997         error_report("tpm-emulator: TPM result for shutdown: 0x%x %s",
 998                      be32_to_cpu(res), tpm_emulator_strerror(be32_to_cpu(res)));
 999     }
1000 }
1001
1002 static void tpm_emulator_inst_finalize(Object *obj)
1003 {
1004     TPMEmulator *tpm_emu = TPM_EMULATOR(obj);
1005     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
1006
1007     tpm_emulator_shutdown(tpm_emu);
1008
1009     object_unref(OBJECT(tpm_emu->data_ioc));
1010
1011     qemu_chr_fe_deinit(&tpm_emu->ctrl_chr, false);
1012
1013     qapi_free_TPMEmulatorOptions(tpm_emu->options);
1014
1015     migrate_del_blocker(&tpm_emu->migration_blocker);
1016
1017     tpm_sized_buffer_reset(&state_blobs->volatil);
1018     tpm_sized_buffer_reset(&state_blobs->permanent);
1019     tpm_sized_buffer_reset(&state_blobs->savestate);
1020
1021     qemu_mutex_destroy(&tpm_emu->mutex);
1022     qemu_del_vm_change_state_handler(tpm_emu->vmstate);
1023
1024     vmstate_unregister(NULL, &vmstate_tpm_emulator, obj);
1025 }
1026
1027 static void tpm_emulator_class_init(ObjectClass *klass, void *data)
1028 {
1029     TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
1030
1031     tbc->type = TPM_TYPE_EMULATOR;
1032     tbc->opts = tpm_emulator_cmdline_opts;
1033     tbc->desc = "TPM emulator backend driver";
1034     tbc->create = tpm_emulator_create;
1035     tbc->startup_tpm = tpm_emulator_startup_tpm;
1036     tbc->cancel_cmd = tpm_emulator_cancel_cmd;
1037     tbc->get_tpm_established_flag = tpm_emulator_get_tpm_established_flag;
1038     tbc->reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag;
1039     tbc->get_tpm_version = tpm_emulator_get_tpm_version;
1040     tbc->get_buffer_size = tpm_emulator_get_buffer_size;
1041     tbc->get_tpm_options = tpm_emulator_get_tpm_options;
1042
1043     tbc->handle_request = tpm_emulator_handle_request;
1044 }
1045
1046 static const TypeInfo tpm_emulator_info = {
1047     .name = TYPE_TPM_EMULATOR,
1048     .parent = TYPE_TPM_BACKEND,
1049     .instance_size = sizeof(TPMEmulator),
1050     .class_init = tpm_emulator_class_init,
1051     .instance_init = tpm_emulator_inst_init,
1052     .instance_finalize = tpm_emulator_inst_finalize,
1053 };
1054
1055 static void tpm_emulator_register(void)
1056 {
1057     type_register_static(&tpm_emulator_info);
1058 }
1059
1060 type_init(tpm_emulator_register)