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