xref: /openbmc/qemu/backends/tpm/tpm_emulator.c (revision 7fb3949d)
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/module.h"
32 #include "qemu/sockets.h"
33 #include "io/channel-socket.h"
34 #include "sysemu/tpm_backend.h"
35 #include "sysemu/tpm_util.h"
36 #include "tpm_int.h"
37 #include "tpm_ioctl.h"
38 #include "migration/blocker.h"
39 #include "migration/vmstate.h"
40 #include "qapi/error.h"
41 #include "qapi/clone-visitor.h"
42 #include "qapi/qapi-visit-tpm.h"
43 #include "chardev/char-fe.h"
44 #include "trace.h"
45 
46 #define TYPE_TPM_EMULATOR "tpm-emulator"
47 #define TPM_EMULATOR(obj) \
48     OBJECT_CHECK(TPMEmulator, (obj), TYPE_TPM_EMULATOR)
49 
50 #define TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(S, cap) (((S)->caps & (cap)) == (cap))
51 
52 /* data structures */
53 
54 /* blobs from the TPM; part of VM state when migrating */
55 typedef struct TPMBlobBuffers {
56     uint32_t permanent_flags;
57     TPMSizedBuffer permanent;
58 
59     uint32_t volatil_flags;
60     TPMSizedBuffer volatil;
61 
62     uint32_t savestate_flags;
63     TPMSizedBuffer savestate;
64 } TPMBlobBuffers;
65 
66 typedef struct TPMEmulator {
67     TPMBackend parent;
68 
69     TPMEmulatorOptions *options;
70     CharBackend ctrl_chr;
71     QIOChannel *data_ioc;
72     TPMVersion tpm_version;
73     ptm_cap caps; /* capabilities of the TPM */
74     uint8_t cur_locty_number; /* last set locality */
75     Error *migration_blocker;
76 
77     QemuMutex mutex;
78 
79     unsigned int established_flag:1;
80     unsigned int established_flag_cached:1;
81 
82     TPMBlobBuffers state_blobs;
83 } TPMEmulator;
84 
85 struct tpm_error {
86     uint32_t tpm_result;
87     const char *string;
88 };
89 
90 static const struct tpm_error tpm_errors[] = {
91     /* TPM 1.2 error codes */
92     { TPM_BAD_PARAMETER   , "a parameter is bad" },
93     { TPM_FAIL            , "operation failed" },
94     { TPM_KEYNOTFOUND     , "key could not be found" },
95     { TPM_BAD_PARAM_SIZE  , "bad parameter size"},
96     { TPM_ENCRYPT_ERROR   , "encryption error" },
97     { TPM_DECRYPT_ERROR   , "decryption error" },
98     { TPM_BAD_KEY_PROPERTY, "bad key property" },
99     { TPM_BAD_MODE        , "bad (encryption) mode" },
100     { TPM_BAD_VERSION     , "bad version identifier" },
101     { TPM_BAD_LOCALITY    , "bad locality" },
102     /* TPM 2 error codes */
103     { TPM_RC_FAILURE     , "operation failed" },
104     { TPM_RC_LOCALITY    , "bad locality"     },
105     { TPM_RC_INSUFFICIENT, "insufficient amount of data" },
106 };
107 
108 static const char *tpm_emulator_strerror(uint32_t tpm_result)
109 {
110     size_t i;
111 
112     for (i = 0; i < ARRAY_SIZE(tpm_errors); i++) {
113         if (tpm_errors[i].tpm_result == tpm_result) {
114             return tpm_errors[i].string;
115         }
116     }
117     return "";
118 }
119 
120 static int tpm_emulator_ctrlcmd(TPMEmulator *tpm, unsigned long cmd, void *msg,
121                                 size_t msg_len_in, size_t msg_len_out)
122 {
123     CharBackend *dev = &tpm->ctrl_chr;
124     uint32_t cmd_no = cpu_to_be32(cmd);
125     ssize_t n = sizeof(uint32_t) + msg_len_in;
126     uint8_t *buf = NULL;
127     int ret = -1;
128 
129     qemu_mutex_lock(&tpm->mutex);
130 
131     buf = g_alloca(n);
132     memcpy(buf, &cmd_no, sizeof(cmd_no));
133     memcpy(buf + sizeof(cmd_no), msg, msg_len_in);
134 
135     n = qemu_chr_fe_write_all(dev, buf, n);
136     if (n <= 0) {
137         goto end;
138     }
139 
140     if (msg_len_out != 0) {
141         n = qemu_chr_fe_read_all(dev, msg, msg_len_out);
142         if (n <= 0) {
143             goto end;
144         }
145     }
146 
147     ret = 0;
148 
149 end:
150     qemu_mutex_unlock(&tpm->mutex);
151     return ret;
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_set_buffer_size(TPMBackend *tb,
310                                         size_t wanted_size,
311                                         size_t *actual_size)
312 {
313     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
314     ptm_setbuffersize psbs;
315 
316     if (tpm_emulator_stop_tpm(tb) < 0) {
317         return -1;
318     }
319 
320     psbs.u.req.buffersize = cpu_to_be32(wanted_size);
321 
322     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_BUFFERSIZE, &psbs,
323                              sizeof(psbs.u.req), sizeof(psbs.u.resp)) < 0) {
324         error_report("tpm-emulator: Could not set buffer size: %s",
325                      strerror(errno));
326         return -1;
327     }
328 
329     psbs.u.resp.tpm_result = be32_to_cpu(psbs.u.resp.tpm_result);
330     if (psbs.u.resp.tpm_result != 0) {
331         error_report("tpm-emulator: TPM result for set buffer size : 0x%x %s",
332                      psbs.u.resp.tpm_result,
333                      tpm_emulator_strerror(psbs.u.resp.tpm_result));
334         return -1;
335     }
336 
337     if (actual_size) {
338         *actual_size = be32_to_cpu(psbs.u.resp.buffersize);
339     }
340 
341     trace_tpm_emulator_set_buffer_size(
342             be32_to_cpu(psbs.u.resp.buffersize),
343             be32_to_cpu(psbs.u.resp.minsize),
344             be32_to_cpu(psbs.u.resp.maxsize));
345 
346     return 0;
347 }
348 
349 static int tpm_emulator_startup_tpm_resume(TPMBackend *tb, size_t buffersize,
350                                      bool is_resume)
351 {
352     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
353     ptm_init init = {
354         .u.req.init_flags = 0,
355     };
356     ptm_res res;
357 
358     trace_tpm_emulator_startup_tpm_resume(is_resume, buffersize);
359 
360     if (buffersize != 0 &&
361         tpm_emulator_set_buffer_size(tb, buffersize, NULL) < 0) {
362         goto err_exit;
363     }
364 
365     if (is_resume) {
366         init.u.req.init_flags |= cpu_to_be32(PTM_INIT_FLAG_DELETE_VOLATILE);
367     }
368 
369     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_INIT, &init, sizeof(init),
370                              sizeof(init)) < 0) {
371         error_report("tpm-emulator: could not send INIT: %s",
372                      strerror(errno));
373         goto err_exit;
374     }
375 
376     res = be32_to_cpu(init.u.resp.tpm_result);
377     if (res) {
378         error_report("tpm-emulator: TPM result for CMD_INIT: 0x%x %s", res,
379                      tpm_emulator_strerror(res));
380         goto err_exit;
381     }
382     return 0;
383 
384 err_exit:
385     return -1;
386 }
387 
388 static int tpm_emulator_startup_tpm(TPMBackend *tb, size_t buffersize)
389 {
390     return tpm_emulator_startup_tpm_resume(tb, buffersize, false);
391 }
392 
393 static bool tpm_emulator_get_tpm_established_flag(TPMBackend *tb)
394 {
395     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
396     ptm_est est;
397 
398     if (tpm_emu->established_flag_cached) {
399         return tpm_emu->established_flag;
400     }
401 
402     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_GET_TPMESTABLISHED, &est,
403                              0, sizeof(est)) < 0) {
404         error_report("tpm-emulator: Could not get the TPM established flag: %s",
405                      strerror(errno));
406         return false;
407     }
408     trace_tpm_emulator_get_tpm_established_flag(est.u.resp.bit);
409 
410     tpm_emu->established_flag_cached = 1;
411     tpm_emu->established_flag = (est.u.resp.bit != 0);
412 
413     return tpm_emu->established_flag;
414 }
415 
416 static int tpm_emulator_reset_tpm_established_flag(TPMBackend *tb,
417                                                    uint8_t locty)
418 {
419     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
420     ptm_reset_est reset_est;
421     ptm_res res;
422 
423     /* only a TPM 2.0 will support this */
424     if (tpm_emu->tpm_version != TPM_VERSION_2_0) {
425         return 0;
426     }
427 
428     reset_est.u.req.loc = tpm_emu->cur_locty_number;
429     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_RESET_TPMESTABLISHED,
430                              &reset_est, sizeof(reset_est),
431                              sizeof(reset_est)) < 0) {
432         error_report("tpm-emulator: Could not reset the establishment bit: %s",
433                      strerror(errno));
434         return -1;
435     }
436 
437     res = be32_to_cpu(reset_est.u.resp.tpm_result);
438     if (res) {
439         error_report(
440             "tpm-emulator: TPM result for rest established flag: 0x%x %s",
441             res, tpm_emulator_strerror(res));
442         return -1;
443     }
444 
445     tpm_emu->established_flag_cached = 0;
446 
447     return 0;
448 }
449 
450 static void tpm_emulator_cancel_cmd(TPMBackend *tb)
451 {
452     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
453     ptm_res res;
454 
455     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, PTM_CAP_CANCEL_TPM_CMD)) {
456         trace_tpm_emulator_cancel_cmd_not_supt();
457         return;
458     }
459 
460     /* FIXME: make the function non-blocking, or it may block a VCPU */
461     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_CANCEL_TPM_CMD, &res, 0,
462                              sizeof(res)) < 0) {
463         error_report("tpm-emulator: Could not cancel command: %s",
464                      strerror(errno));
465     } else if (res != 0) {
466         error_report("tpm-emulator: Failed to cancel TPM: 0x%x",
467                      be32_to_cpu(res));
468     }
469 }
470 
471 static TPMVersion tpm_emulator_get_tpm_version(TPMBackend *tb)
472 {
473     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
474 
475     return tpm_emu->tpm_version;
476 }
477 
478 static size_t tpm_emulator_get_buffer_size(TPMBackend *tb)
479 {
480     size_t actual_size;
481 
482     if (tpm_emulator_set_buffer_size(tb, 0, &actual_size) < 0) {
483         return 4096;
484     }
485 
486     return actual_size;
487 }
488 
489 static int tpm_emulator_block_migration(TPMEmulator *tpm_emu)
490 {
491     Error *err = NULL;
492     ptm_cap caps = PTM_CAP_GET_STATEBLOB | PTM_CAP_SET_STATEBLOB |
493                    PTM_CAP_STOP;
494 
495     if (!TPM_EMULATOR_IMPLEMENTS_ALL_CAPS(tpm_emu, caps)) {
496         error_setg(&tpm_emu->migration_blocker,
497                    "Migration disabled: TPM emulator does not support "
498                    "migration");
499         migrate_add_blocker(tpm_emu->migration_blocker, &err);
500         if (err) {
501             error_report_err(err);
502             error_free(tpm_emu->migration_blocker);
503             tpm_emu->migration_blocker = NULL;
504 
505             return -1;
506         }
507     }
508 
509     return 0;
510 }
511 
512 static int tpm_emulator_prepare_data_fd(TPMEmulator *tpm_emu)
513 {
514     ptm_res res;
515     Error *err = NULL;
516     int fds[2] = { -1, -1 };
517 
518     if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) < 0) {
519         error_report("tpm-emulator: Failed to create socketpair");
520         return -1;
521     }
522 
523     qemu_chr_fe_set_msgfds(&tpm_emu->ctrl_chr, fds + 1, 1);
524 
525     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_DATAFD, &res, 0,
526                              sizeof(res)) < 0 || res != 0) {
527         error_report("tpm-emulator: Failed to send CMD_SET_DATAFD: %s",
528                      strerror(errno));
529         goto err_exit;
530     }
531 
532     tpm_emu->data_ioc = QIO_CHANNEL(qio_channel_socket_new_fd(fds[0], &err));
533     if (err) {
534         error_prepend(&err, "tpm-emulator: Failed to create io channel: ");
535         error_report_err(err);
536         goto err_exit;
537     }
538 
539     closesocket(fds[1]);
540 
541     return 0;
542 
543 err_exit:
544     closesocket(fds[0]);
545     closesocket(fds[1]);
546     return -1;
547 }
548 
549 static int tpm_emulator_handle_device_opts(TPMEmulator *tpm_emu, QemuOpts *opts)
550 {
551     const char *value;
552 
553     value = qemu_opt_get(opts, "chardev");
554     if (value) {
555         Error *err = NULL;
556         Chardev *dev = qemu_chr_find(value);
557 
558         if (!dev) {
559             error_report("tpm-emulator: tpm chardev '%s' not found.", value);
560             goto err;
561         }
562 
563         if (!qemu_chr_fe_init(&tpm_emu->ctrl_chr, dev, &err)) {
564             error_prepend(&err, "tpm-emulator: No valid chardev found at '%s':",
565                           value);
566             error_report_err(err);
567             goto err;
568         }
569 
570         tpm_emu->options->chardev = g_strdup(value);
571     }
572 
573     if (tpm_emulator_prepare_data_fd(tpm_emu) < 0) {
574         goto err;
575     }
576 
577     /* FIXME: tpm_util_test_tpmdev() accepts only on socket fd, as it also used
578      * by passthrough driver, which not yet using GIOChannel.
579      */
580     if (tpm_util_test_tpmdev(QIO_CHANNEL_SOCKET(tpm_emu->data_ioc)->fd,
581                              &tpm_emu->tpm_version)) {
582         error_report("'%s' is not emulating TPM device. Error: %s",
583                       tpm_emu->options->chardev, strerror(errno));
584         goto err;
585     }
586 
587     switch (tpm_emu->tpm_version) {
588     case TPM_VERSION_1_2:
589         trace_tpm_emulator_handle_device_opts_tpm12();
590         break;
591     case TPM_VERSION_2_0:
592         trace_tpm_emulator_handle_device_opts_tpm2();
593         break;
594     default:
595         trace_tpm_emulator_handle_device_opts_unspec();
596     }
597 
598     if (tpm_emulator_probe_caps(tpm_emu) ||
599         tpm_emulator_check_caps(tpm_emu)) {
600         goto err;
601     }
602 
603     return tpm_emulator_block_migration(tpm_emu);
604 
605 err:
606     trace_tpm_emulator_handle_device_opts_startup_error();
607 
608     return -1;
609 }
610 
611 static TPMBackend *tpm_emulator_create(QemuOpts *opts)
612 {
613     TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
614 
615     if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
616         object_unref(OBJECT(tb));
617         return NULL;
618     }
619 
620     return tb;
621 }
622 
623 static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
624 {
625     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
626     TpmTypeOptions *options = g_new0(TpmTypeOptions, 1);
627 
628     options->type = TPM_TYPE_OPTIONS_KIND_EMULATOR;
629     options->u.emulator.data = QAPI_CLONE(TPMEmulatorOptions, tpm_emu->options);
630 
631     return options;
632 }
633 
634 static const QemuOptDesc tpm_emulator_cmdline_opts[] = {
635     TPM_STANDARD_CMDLINE_OPTS,
636     {
637         .name = "chardev",
638         .type = QEMU_OPT_STRING,
639         .help = "Character device to use for out-of-band control messages",
640     },
641     { /* end of list */ },
642 };
643 
644 /*
645  * Transfer a TPM state blob from the TPM into a provided buffer.
646  *
647  * @tpm_emu: TPMEmulator
648  * @type: the type of blob to transfer
649  * @tsb: the TPMSizeBuffer to fill with the blob
650  * @flags: the flags to return to the caller
651  */
652 static int tpm_emulator_get_state_blob(TPMEmulator *tpm_emu,
653                                        uint8_t type,
654                                        TPMSizedBuffer *tsb,
655                                        uint32_t *flags)
656 {
657     ptm_getstate pgs;
658     ptm_res res;
659     ssize_t n;
660     uint32_t totlength, length;
661 
662     tpm_sized_buffer_reset(tsb);
663 
664     pgs.u.req.state_flags = cpu_to_be32(PTM_STATE_FLAG_DECRYPTED);
665     pgs.u.req.type = cpu_to_be32(type);
666     pgs.u.req.offset = 0;
667 
668     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_GET_STATEBLOB,
669                              &pgs, sizeof(pgs.u.req),
670                              offsetof(ptm_getstate, u.resp.data)) < 0) {
671         error_report("tpm-emulator: could not get state blob type %d : %s",
672                      type, strerror(errno));
673         return -1;
674     }
675 
676     res = be32_to_cpu(pgs.u.resp.tpm_result);
677     if (res != 0 && (res & 0x800) == 0) {
678         error_report("tpm-emulator: Getting the stateblob (type %d) failed "
679                      "with a TPM error 0x%x %s", type, res,
680                      tpm_emulator_strerror(res));
681         return -1;
682     }
683 
684     totlength = be32_to_cpu(pgs.u.resp.totlength);
685     length = be32_to_cpu(pgs.u.resp.length);
686     if (totlength != length) {
687         error_report("tpm-emulator: Expecting to read %u bytes "
688                      "but would get %u", totlength, length);
689         return -1;
690     }
691 
692     *flags = be32_to_cpu(pgs.u.resp.state_flags);
693 
694     if (totlength > 0) {
695         tsb->buffer = g_try_malloc(totlength);
696         if (!tsb->buffer) {
697             error_report("tpm-emulator: Out of memory allocating %u bytes",
698                          totlength);
699             return -1;
700         }
701 
702         n = qemu_chr_fe_read_all(&tpm_emu->ctrl_chr, tsb->buffer, totlength);
703         if (n != totlength) {
704             error_report("tpm-emulator: Could not read stateblob (type %d); "
705                          "expected %u bytes, got %zd",
706                          type, totlength, n);
707             return -1;
708         }
709     }
710     tsb->size = totlength;
711 
712     trace_tpm_emulator_get_state_blob(type, tsb->size, *flags);
713 
714     return 0;
715 }
716 
717 static int tpm_emulator_get_state_blobs(TPMEmulator *tpm_emu)
718 {
719     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
720 
721     if (tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_PERMANENT,
722                                     &state_blobs->permanent,
723                                     &state_blobs->permanent_flags) < 0 ||
724         tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_VOLATILE,
725                                     &state_blobs->volatil,
726                                     &state_blobs->volatil_flags) < 0 ||
727         tpm_emulator_get_state_blob(tpm_emu, PTM_BLOB_TYPE_SAVESTATE,
728                                     &state_blobs->savestate,
729                                     &state_blobs->savestate_flags) < 0) {
730         goto err_exit;
731     }
732 
733     return 0;
734 
735  err_exit:
736     tpm_sized_buffer_reset(&state_blobs->volatil);
737     tpm_sized_buffer_reset(&state_blobs->permanent);
738     tpm_sized_buffer_reset(&state_blobs->savestate);
739 
740     return -1;
741 }
742 
743 /*
744  * Transfer a TPM state blob to the TPM emulator.
745  *
746  * @tpm_emu: TPMEmulator
747  * @type: the type of TPM state blob to transfer
748  * @tsb: TPMSizedBuffer containing the TPM state blob
749  * @flags: Flags describing the (encryption) state of the TPM state blob
750  */
751 static int tpm_emulator_set_state_blob(TPMEmulator *tpm_emu,
752                                        uint32_t type,
753                                        TPMSizedBuffer *tsb,
754                                        uint32_t flags)
755 {
756     ssize_t n;
757     ptm_setstate pss;
758     ptm_res tpm_result;
759 
760     if (tsb->size == 0) {
761         return 0;
762     }
763 
764     pss = (ptm_setstate) {
765         .u.req.state_flags = cpu_to_be32(flags),
766         .u.req.type = cpu_to_be32(type),
767         .u.req.length = cpu_to_be32(tsb->size),
768     };
769 
770     /* write the header only */
771     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SET_STATEBLOB, &pss,
772                              offsetof(ptm_setstate, u.req.data), 0) < 0) {
773         error_report("tpm-emulator: could not set state blob type %d : %s",
774                      type, strerror(errno));
775         return -1;
776     }
777 
778     /* now the body */
779     n = qemu_chr_fe_write_all(&tpm_emu->ctrl_chr, tsb->buffer, tsb->size);
780     if (n != tsb->size) {
781         error_report("tpm-emulator: Writing the stateblob (type %d) "
782                      "failed; could not write %u bytes, but only %zd",
783                      type, tsb->size, n);
784         return -1;
785     }
786 
787     /* now get the result */
788     n = qemu_chr_fe_read_all(&tpm_emu->ctrl_chr,
789                              (uint8_t *)&pss, sizeof(pss.u.resp));
790     if (n != sizeof(pss.u.resp)) {
791         error_report("tpm-emulator: Reading response from writing stateblob "
792                      "(type %d) failed; expected %zu bytes, got %zd", type,
793                      sizeof(pss.u.resp), n);
794         return -1;
795     }
796 
797     tpm_result = be32_to_cpu(pss.u.resp.tpm_result);
798     if (tpm_result != 0) {
799         error_report("tpm-emulator: Setting the stateblob (type %d) failed "
800                      "with a TPM error 0x%x %s", type, tpm_result,
801                      tpm_emulator_strerror(tpm_result));
802         return -1;
803     }
804 
805     trace_tpm_emulator_set_state_blob(type, tsb->size, flags);
806 
807     return 0;
808 }
809 
810 /*
811  * Set all the TPM state blobs.
812  *
813  * Returns a negative errno code in case of error.
814  */
815 static int tpm_emulator_set_state_blobs(TPMBackend *tb)
816 {
817     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
818     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
819 
820     trace_tpm_emulator_set_state_blobs();
821 
822     if (tpm_emulator_stop_tpm(tb) < 0) {
823         trace_tpm_emulator_set_state_blobs_error("Could not stop TPM");
824         return -EIO;
825     }
826 
827     if (tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_PERMANENT,
828                                     &state_blobs->permanent,
829                                     state_blobs->permanent_flags) < 0 ||
830         tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_VOLATILE,
831                                     &state_blobs->volatil,
832                                     state_blobs->volatil_flags) < 0 ||
833         tpm_emulator_set_state_blob(tpm_emu, PTM_BLOB_TYPE_SAVESTATE,
834                                     &state_blobs->savestate,
835                                     state_blobs->savestate_flags) < 0) {
836         return -EIO;
837     }
838 
839     trace_tpm_emulator_set_state_blobs_done();
840 
841     return 0;
842 }
843 
844 static int tpm_emulator_pre_save(void *opaque)
845 {
846     TPMBackend *tb = opaque;
847     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
848 
849     trace_tpm_emulator_pre_save();
850 
851     tpm_backend_finish_sync(tb);
852 
853     /* get the state blobs from the TPM */
854     return tpm_emulator_get_state_blobs(tpm_emu);
855 }
856 
857 /*
858  * Load the TPM state blobs into the TPM.
859  *
860  * Returns negative errno codes in case of error.
861  */
862 static int tpm_emulator_post_load(void *opaque, int version_id)
863 {
864     TPMBackend *tb = opaque;
865     int ret;
866 
867     ret = tpm_emulator_set_state_blobs(tb);
868     if (ret < 0) {
869         return ret;
870     }
871 
872     if (tpm_emulator_startup_tpm_resume(tb, 0, true) < 0) {
873         return -EIO;
874     }
875 
876     return 0;
877 }
878 
879 static const VMStateDescription vmstate_tpm_emulator = {
880     .name = "tpm-emulator",
881     .version_id = 0,
882     .pre_save = tpm_emulator_pre_save,
883     .post_load = tpm_emulator_post_load,
884     .fields = (VMStateField[]) {
885         VMSTATE_UINT32(state_blobs.permanent_flags, TPMEmulator),
886         VMSTATE_UINT32(state_blobs.permanent.size, TPMEmulator),
887         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.permanent.buffer,
888                                      TPMEmulator, 0, 0,
889                                      state_blobs.permanent.size),
890 
891         VMSTATE_UINT32(state_blobs.volatil_flags, TPMEmulator),
892         VMSTATE_UINT32(state_blobs.volatil.size, TPMEmulator),
893         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.volatil.buffer,
894                                      TPMEmulator, 0, 0,
895                                      state_blobs.volatil.size),
896 
897         VMSTATE_UINT32(state_blobs.savestate_flags, TPMEmulator),
898         VMSTATE_UINT32(state_blobs.savestate.size, TPMEmulator),
899         VMSTATE_VBUFFER_ALLOC_UINT32(state_blobs.savestate.buffer,
900                                      TPMEmulator, 0, 0,
901                                      state_blobs.savestate.size),
902 
903         VMSTATE_END_OF_LIST()
904     }
905 };
906 
907 static void tpm_emulator_inst_init(Object *obj)
908 {
909     TPMEmulator *tpm_emu = TPM_EMULATOR(obj);
910 
911     trace_tpm_emulator_inst_init();
912 
913     tpm_emu->options = g_new0(TPMEmulatorOptions, 1);
914     tpm_emu->cur_locty_number = ~0;
915     qemu_mutex_init(&tpm_emu->mutex);
916 
917     vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY,
918                      &vmstate_tpm_emulator, obj);
919 }
920 
921 /*
922  * Gracefully shut down the external TPM
923  */
924 static void tpm_emulator_shutdown(TPMEmulator *tpm_emu)
925 {
926     ptm_res res;
927 
928     if (tpm_emulator_ctrlcmd(tpm_emu, CMD_SHUTDOWN, &res, 0, sizeof(res)) < 0) {
929         error_report("tpm-emulator: Could not cleanly shutdown the TPM: %s",
930                      strerror(errno));
931     } else if (res != 0) {
932         error_report("tpm-emulator: TPM result for shutdown: 0x%x %s",
933                      be32_to_cpu(res), tpm_emulator_strerror(be32_to_cpu(res)));
934     }
935 }
936 
937 static void tpm_emulator_inst_finalize(Object *obj)
938 {
939     TPMEmulator *tpm_emu = TPM_EMULATOR(obj);
940     TPMBlobBuffers *state_blobs = &tpm_emu->state_blobs;
941 
942     tpm_emulator_shutdown(tpm_emu);
943 
944     object_unref(OBJECT(tpm_emu->data_ioc));
945 
946     qemu_chr_fe_deinit(&tpm_emu->ctrl_chr, false);
947 
948     qapi_free_TPMEmulatorOptions(tpm_emu->options);
949 
950     if (tpm_emu->migration_blocker) {
951         migrate_del_blocker(tpm_emu->migration_blocker);
952         error_free(tpm_emu->migration_blocker);
953     }
954 
955     tpm_sized_buffer_reset(&state_blobs->volatil);
956     tpm_sized_buffer_reset(&state_blobs->permanent);
957     tpm_sized_buffer_reset(&state_blobs->savestate);
958 
959     qemu_mutex_destroy(&tpm_emu->mutex);
960 
961     vmstate_unregister(NULL, &vmstate_tpm_emulator, obj);
962 }
963 
964 static void tpm_emulator_class_init(ObjectClass *klass, void *data)
965 {
966     TPMBackendClass *tbc = TPM_BACKEND_CLASS(klass);
967 
968     tbc->type = TPM_TYPE_EMULATOR;
969     tbc->opts = tpm_emulator_cmdline_opts;
970     tbc->desc = "TPM emulator backend driver";
971     tbc->create = tpm_emulator_create;
972     tbc->startup_tpm = tpm_emulator_startup_tpm;
973     tbc->cancel_cmd = tpm_emulator_cancel_cmd;
974     tbc->get_tpm_established_flag = tpm_emulator_get_tpm_established_flag;
975     tbc->reset_tpm_established_flag = tpm_emulator_reset_tpm_established_flag;
976     tbc->get_tpm_version = tpm_emulator_get_tpm_version;
977     tbc->get_buffer_size = tpm_emulator_get_buffer_size;
978     tbc->get_tpm_options = tpm_emulator_get_tpm_options;
979 
980     tbc->handle_request = tpm_emulator_handle_request;
981 }
982 
983 static const TypeInfo tpm_emulator_info = {
984     .name = TYPE_TPM_EMULATOR,
985     .parent = TYPE_TPM_BACKEND,
986     .instance_size = sizeof(TPMEmulator),
987     .class_init = tpm_emulator_class_init,
988     .instance_init = tpm_emulator_inst_init,
989     .instance_finalize = tpm_emulator_inst_finalize,
990 };
991 
992 static void tpm_emulator_register(void)
993 {
994     type_register_static(&tpm_emulator_info);
995 }
996 
997 type_init(tpm_emulator_register)
998