GNU Linux-libre 4.9.333-gnu1
[releases.git] / drivers / char / tpm / tpm2-cmd.c
1 /*
2  * Copyright (C) 2014, 2015 Intel Corporation
3  *
4  * Authors:
5  * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
6  *
7  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
8  *
9  * This file contains TPM2 protocol implementations of the commands
10  * used by the kernel internally.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; version 2
15  * of the License.
16  */
17
18 #include "tpm.h"
19 #include <crypto/hash_info.h>
20 #include <keys/trusted-type.h>
21
22 enum tpm2_object_attributes {
23         TPM2_OA_USER_WITH_AUTH          = BIT(6),
24 };
25
26 enum tpm2_session_attributes {
27         TPM2_SA_CONTINUE_SESSION        = BIT(0),
28 };
29
30 struct tpm2_startup_in {
31         __be16  startup_type;
32 } __packed;
33
34 struct tpm2_self_test_in {
35         u8      full_test;
36 } __packed;
37
38 struct tpm2_pcr_read_in {
39         __be32  pcr_selects_cnt;
40         __be16  hash_alg;
41         u8      pcr_select_size;
42         u8      pcr_select[TPM2_PCR_SELECT_MIN];
43 } __packed;
44
45 struct tpm2_pcr_read_out {
46         __be32  update_cnt;
47         __be32  pcr_selects_cnt;
48         __be16  hash_alg;
49         u8      pcr_select_size;
50         u8      pcr_select[TPM2_PCR_SELECT_MIN];
51         __be32  digests_cnt;
52         __be16  digest_size;
53         u8      digest[TPM_DIGEST_SIZE];
54 } __packed;
55
56 struct tpm2_null_auth_area {
57         __be32                  handle;
58         __be16                  nonce_size;
59         u8                      attributes;
60         __be16                  auth_size;
61 } __packed;
62
63 struct tpm2_pcr_extend_in {
64         __be32                          pcr_idx;
65         __be32                          auth_area_size;
66         struct tpm2_null_auth_area      auth_area;
67         __be32                          digest_cnt;
68         __be16                          hash_alg;
69         u8                              digest[TPM_DIGEST_SIZE];
70 } __packed;
71
72 struct tpm2_get_tpm_pt_in {
73         __be32  cap_id;
74         __be32  property_id;
75         __be32  property_cnt;
76 } __packed;
77
78 struct tpm2_get_tpm_pt_out {
79         u8      more_data;
80         __be32  subcap_id;
81         __be32  property_cnt;
82         __be32  property_id;
83         __be32  value;
84 } __packed;
85
86 struct tpm2_get_random_in {
87         __be16  size;
88 } __packed;
89
90 struct tpm2_get_random_out {
91         __be16  size;
92         u8      buffer[TPM_MAX_RNG_DATA];
93 } __packed;
94
95 union tpm2_cmd_params {
96         struct  tpm2_startup_in         startup_in;
97         struct  tpm2_self_test_in       selftest_in;
98         struct  tpm2_pcr_read_in        pcrread_in;
99         struct  tpm2_pcr_read_out       pcrread_out;
100         struct  tpm2_pcr_extend_in      pcrextend_in;
101         struct  tpm2_get_tpm_pt_in      get_tpm_pt_in;
102         struct  tpm2_get_tpm_pt_out     get_tpm_pt_out;
103         struct  tpm2_get_random_in      getrandom_in;
104         struct  tpm2_get_random_out     getrandom_out;
105 };
106
107 struct tpm2_cmd {
108         tpm_cmd_header          header;
109         union tpm2_cmd_params   params;
110 } __packed;
111
112 struct tpm2_hash {
113         unsigned int crypto_id;
114         unsigned int tpm_id;
115 };
116
117 static struct tpm2_hash tpm2_hash_map[] = {
118         {HASH_ALGO_SHA1, TPM2_ALG_SHA1},
119         {HASH_ALGO_SHA256, TPM2_ALG_SHA256},
120         {HASH_ALGO_SHA384, TPM2_ALG_SHA384},
121         {HASH_ALGO_SHA512, TPM2_ALG_SHA512},
122         {HASH_ALGO_SM3_256, TPM2_ALG_SM3_256},
123 };
124
125 /*
126  * Array with one entry per ordinal defining the maximum amount
127  * of time the chip could take to return the result. The values
128  * of the SHORT, MEDIUM, and LONG durations are taken from the
129  * PC Client Profile (PTP) specification.
130  */
131 static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
132         TPM_UNDEFINED,          /* 11F */
133         TPM_UNDEFINED,          /* 120 */
134         TPM_LONG,               /* 121 */
135         TPM_UNDEFINED,          /* 122 */
136         TPM_UNDEFINED,          /* 123 */
137         TPM_UNDEFINED,          /* 124 */
138         TPM_UNDEFINED,          /* 125 */
139         TPM_UNDEFINED,          /* 126 */
140         TPM_UNDEFINED,          /* 127 */
141         TPM_UNDEFINED,          /* 128 */
142         TPM_LONG,               /* 129 */
143         TPM_UNDEFINED,          /* 12a */
144         TPM_UNDEFINED,          /* 12b */
145         TPM_UNDEFINED,          /* 12c */
146         TPM_UNDEFINED,          /* 12d */
147         TPM_UNDEFINED,          /* 12e */
148         TPM_UNDEFINED,          /* 12f */
149         TPM_UNDEFINED,          /* 130 */
150         TPM_UNDEFINED,          /* 131 */
151         TPM_UNDEFINED,          /* 132 */
152         TPM_UNDEFINED,          /* 133 */
153         TPM_UNDEFINED,          /* 134 */
154         TPM_UNDEFINED,          /* 135 */
155         TPM_UNDEFINED,          /* 136 */
156         TPM_UNDEFINED,          /* 137 */
157         TPM_UNDEFINED,          /* 138 */
158         TPM_UNDEFINED,          /* 139 */
159         TPM_UNDEFINED,          /* 13a */
160         TPM_UNDEFINED,          /* 13b */
161         TPM_UNDEFINED,          /* 13c */
162         TPM_UNDEFINED,          /* 13d */
163         TPM_MEDIUM,             /* 13e */
164         TPM_UNDEFINED,          /* 13f */
165         TPM_UNDEFINED,          /* 140 */
166         TPM_UNDEFINED,          /* 141 */
167         TPM_UNDEFINED,          /* 142 */
168         TPM_LONG,               /* 143 */
169         TPM_MEDIUM,             /* 144 */
170         TPM_UNDEFINED,          /* 145 */
171         TPM_UNDEFINED,          /* 146 */
172         TPM_UNDEFINED,          /* 147 */
173         TPM_UNDEFINED,          /* 148 */
174         TPM_UNDEFINED,          /* 149 */
175         TPM_UNDEFINED,          /* 14a */
176         TPM_UNDEFINED,          /* 14b */
177         TPM_UNDEFINED,          /* 14c */
178         TPM_UNDEFINED,          /* 14d */
179         TPM_LONG,               /* 14e */
180         TPM_UNDEFINED,          /* 14f */
181         TPM_UNDEFINED,          /* 150 */
182         TPM_UNDEFINED,          /* 151 */
183         TPM_UNDEFINED,          /* 152 */
184         TPM_UNDEFINED,          /* 153 */
185         TPM_UNDEFINED,          /* 154 */
186         TPM_UNDEFINED,          /* 155 */
187         TPM_UNDEFINED,          /* 156 */
188         TPM_UNDEFINED,          /* 157 */
189         TPM_UNDEFINED,          /* 158 */
190         TPM_UNDEFINED,          /* 159 */
191         TPM_UNDEFINED,          /* 15a */
192         TPM_UNDEFINED,          /* 15b */
193         TPM_MEDIUM,             /* 15c */
194         TPM_UNDEFINED,          /* 15d */
195         TPM_UNDEFINED,          /* 15e */
196         TPM_UNDEFINED,          /* 15f */
197         TPM_UNDEFINED,          /* 160 */
198         TPM_UNDEFINED,          /* 161 */
199         TPM_UNDEFINED,          /* 162 */
200         TPM_UNDEFINED,          /* 163 */
201         TPM_UNDEFINED,          /* 164 */
202         TPM_UNDEFINED,          /* 165 */
203         TPM_UNDEFINED,          /* 166 */
204         TPM_UNDEFINED,          /* 167 */
205         TPM_UNDEFINED,          /* 168 */
206         TPM_UNDEFINED,          /* 169 */
207         TPM_UNDEFINED,          /* 16a */
208         TPM_UNDEFINED,          /* 16b */
209         TPM_UNDEFINED,          /* 16c */
210         TPM_UNDEFINED,          /* 16d */
211         TPM_UNDEFINED,          /* 16e */
212         TPM_UNDEFINED,          /* 16f */
213         TPM_UNDEFINED,          /* 170 */
214         TPM_UNDEFINED,          /* 171 */
215         TPM_UNDEFINED,          /* 172 */
216         TPM_UNDEFINED,          /* 173 */
217         TPM_UNDEFINED,          /* 174 */
218         TPM_UNDEFINED,          /* 175 */
219         TPM_UNDEFINED,          /* 176 */
220         TPM_LONG,               /* 177 */
221         TPM_UNDEFINED,          /* 178 */
222         TPM_UNDEFINED,          /* 179 */
223         TPM_MEDIUM,             /* 17a */
224         TPM_LONG,               /* 17b */
225         TPM_UNDEFINED,          /* 17c */
226         TPM_UNDEFINED,          /* 17d */
227         TPM_UNDEFINED,          /* 17e */
228         TPM_UNDEFINED,          /* 17f */
229         TPM_UNDEFINED,          /* 180 */
230         TPM_UNDEFINED,          /* 181 */
231         TPM_MEDIUM,             /* 182 */
232         TPM_UNDEFINED,          /* 183 */
233         TPM_UNDEFINED,          /* 184 */
234         TPM_MEDIUM,             /* 185 */
235         TPM_MEDIUM,             /* 186 */
236         TPM_UNDEFINED,          /* 187 */
237         TPM_UNDEFINED,          /* 188 */
238         TPM_UNDEFINED,          /* 189 */
239         TPM_UNDEFINED,          /* 18a */
240         TPM_UNDEFINED,          /* 18b */
241         TPM_UNDEFINED,          /* 18c */
242         TPM_UNDEFINED,          /* 18d */
243         TPM_UNDEFINED,          /* 18e */
244         TPM_UNDEFINED           /* 18f */
245 };
246
247 #define TPM2_PCR_READ_IN_SIZE \
248         (sizeof(struct tpm_input_header) + \
249          sizeof(struct tpm2_pcr_read_in))
250
251 static const struct tpm_input_header tpm2_pcrread_header = {
252         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
253         .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE),
254         .ordinal = cpu_to_be32(TPM2_CC_PCR_READ)
255 };
256
257 /**
258  * tpm2_pcr_read() - read a PCR value
259  * @chip:       TPM chip to use.
260  * @pcr_idx:    index of the PCR to read.
261  * @ref_buf:    buffer to store the resulting hash,
262  *
263  * 0 is returned when the operation is successful. If a negative number is
264  * returned it remarks a POSIX error code. If a positive number is returned
265  * it remarks a TPM error.
266  */
267 int tpm2_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
268 {
269         int rc;
270         struct tpm2_cmd cmd;
271         u8 *buf;
272
273         if (pcr_idx >= TPM2_PLATFORM_PCR)
274                 return -EINVAL;
275
276         cmd.header.in = tpm2_pcrread_header;
277         cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
278         cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
279         cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
280
281         memset(cmd.params.pcrread_in.pcr_select, 0,
282                sizeof(cmd.params.pcrread_in.pcr_select));
283         cmd.params.pcrread_in.pcr_select[pcr_idx >> 3] = 1 << (pcr_idx & 0x7);
284
285         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
286                               "attempting to read a pcr value");
287         if (rc == 0) {
288                 buf = cmd.params.pcrread_out.digest;
289                 memcpy(res_buf, buf, TPM_DIGEST_SIZE);
290         }
291
292         return rc;
293 }
294
295 #define TPM2_GET_PCREXTEND_IN_SIZE \
296         (sizeof(struct tpm_input_header) + \
297          sizeof(struct tpm2_pcr_extend_in))
298
299 static const struct tpm_input_header tpm2_pcrextend_header = {
300         .tag = cpu_to_be16(TPM2_ST_SESSIONS),
301         .length = cpu_to_be32(TPM2_GET_PCREXTEND_IN_SIZE),
302         .ordinal = cpu_to_be32(TPM2_CC_PCR_EXTEND)
303 };
304
305 /**
306  * tpm2_pcr_extend() - extend a PCR value
307  * @chip:       TPM chip to use.
308  * @pcr_idx:    index of the PCR.
309  * @hash:       hash value to use for the extend operation.
310  *
311  * 0 is returned when the operation is successful. If a negative number is
312  * returned it remarks a POSIX error code. If a positive number is returned
313  * it remarks a TPM error.
314  */
315 int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
316 {
317         struct tpm2_cmd cmd;
318         int rc;
319
320         cmd.header.in = tpm2_pcrextend_header;
321         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
322         cmd.params.pcrextend_in.auth_area_size =
323                 cpu_to_be32(sizeof(struct tpm2_null_auth_area));
324         cmd.params.pcrextend_in.auth_area.handle =
325                 cpu_to_be32(TPM2_RS_PW);
326         cmd.params.pcrextend_in.auth_area.nonce_size = 0;
327         cmd.params.pcrextend_in.auth_area.attributes = 0;
328         cmd.params.pcrextend_in.auth_area.auth_size = 0;
329         cmd.params.pcrextend_in.digest_cnt = cpu_to_be32(1);
330         cmd.params.pcrextend_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
331         memcpy(cmd.params.pcrextend_in.digest, hash, TPM_DIGEST_SIZE);
332
333         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
334                               "attempting extend a PCR value");
335
336         return rc;
337 }
338
339 #define TPM2_GETRANDOM_IN_SIZE \
340         (sizeof(struct tpm_input_header) + \
341          sizeof(struct tpm2_get_random_in))
342
343 static const struct tpm_input_header tpm2_getrandom_header = {
344         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
345         .length = cpu_to_be32(TPM2_GETRANDOM_IN_SIZE),
346         .ordinal = cpu_to_be32(TPM2_CC_GET_RANDOM)
347 };
348
349 /**
350  * tpm2_get_random() - get random bytes from the TPM RNG
351  * @chip: TPM chip to use
352  * @out: destination buffer for the random bytes
353  * @max: the max number of bytes to write to @out
354  *
355  * 0 is returned when the operation is successful. If a negative number is
356  * returned it remarks a POSIX error code. If a positive number is returned
357  * it remarks a TPM error.
358  */
359 int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
360 {
361         struct tpm2_cmd cmd;
362         u32 recd;
363         u32 num_bytes;
364         int err;
365         int total = 0;
366         int retries = 5;
367         u8 *dest = out;
368
369         num_bytes = min_t(u32, max, sizeof(cmd.params.getrandom_out.buffer));
370
371         if (!out || !num_bytes ||
372             max > sizeof(cmd.params.getrandom_out.buffer))
373                 return -EINVAL;
374
375         do {
376                 cmd.header.in = tpm2_getrandom_header;
377                 cmd.params.getrandom_in.size = cpu_to_be16(num_bytes);
378
379                 err = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
380                                        "attempting get random");
381                 if (err)
382                         break;
383
384                 recd = min_t(u32, be16_to_cpu(cmd.params.getrandom_out.size),
385                              num_bytes);
386                 memcpy(dest, cmd.params.getrandom_out.buffer, recd);
387
388                 dest += recd;
389                 total += recd;
390                 num_bytes -= recd;
391         } while (retries-- && total < max);
392
393         return total ? total : -EIO;
394 }
395
396 #define TPM2_GET_TPM_PT_IN_SIZE \
397         (sizeof(struct tpm_input_header) + \
398          sizeof(struct tpm2_get_tpm_pt_in))
399
400 static const struct tpm_input_header tpm2_get_tpm_pt_header = {
401         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
402         .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
403         .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
404 };
405
406 /**
407  * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated with
408  * tpm_buf_alloc().
409  *
410  * @param buf: an allocated tpm_buf instance
411  * @param nonce: the session nonce, may be NULL if not used
412  * @param nonce_len: the session nonce length, may be 0 if not used
413  * @param attributes: the session attributes
414  * @param hmac: the session HMAC or password, may be NULL if not used
415  * @param hmac_len: the session HMAC or password length, maybe 0 if not used
416  */
417 static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle,
418                                  const u8 *nonce, u16 nonce_len,
419                                  u8 attributes,
420                                  const u8 *hmac, u16 hmac_len)
421 {
422         tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len);
423         tpm_buf_append_u32(buf, session_handle);
424         tpm_buf_append_u16(buf, nonce_len);
425
426         if (nonce && nonce_len)
427                 tpm_buf_append(buf, nonce, nonce_len);
428
429         tpm_buf_append_u8(buf, attributes);
430         tpm_buf_append_u16(buf, hmac_len);
431
432         if (hmac && hmac_len)
433                 tpm_buf_append(buf, hmac, hmac_len);
434 }
435
436 /**
437  * tpm2_seal_trusted() - seal the payload of a trusted key
438  * @chip_num: TPM chip to use
439  * @payload: the key data in clear and encrypted form
440  * @options: authentication values and other options
441  *
442  * Return: < 0 on error and 0 on success.
443  */
444 int tpm2_seal_trusted(struct tpm_chip *chip,
445                       struct trusted_key_payload *payload,
446                       struct trusted_key_options *options)
447 {
448         unsigned int blob_len;
449         struct tpm_buf buf;
450         u32 hash;
451         int i;
452         int rc;
453
454         for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) {
455                 if (options->hash == tpm2_hash_map[i].crypto_id) {
456                         hash = tpm2_hash_map[i].tpm_id;
457                         break;
458                 }
459         }
460
461         if (i == ARRAY_SIZE(tpm2_hash_map))
462                 return -EINVAL;
463
464         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
465         if (rc)
466                 return rc;
467
468         tpm_buf_append_u32(&buf, options->keyhandle);
469         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
470                              NULL /* nonce */, 0,
471                              0 /* session_attributes */,
472                              options->keyauth /* hmac */,
473                              TPM_DIGEST_SIZE);
474
475         /* sensitive */
476         tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1);
477
478         tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE);
479         tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE);
480         tpm_buf_append_u16(&buf, payload->key_len + 1);
481         tpm_buf_append(&buf, payload->key, payload->key_len);
482         tpm_buf_append_u8(&buf, payload->migratable);
483
484         /* public */
485         tpm_buf_append_u16(&buf, 14 + options->policydigest_len);
486         tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH);
487         tpm_buf_append_u16(&buf, hash);
488
489         /* policy */
490         if (options->policydigest_len) {
491                 tpm_buf_append_u32(&buf, 0);
492                 tpm_buf_append_u16(&buf, options->policydigest_len);
493                 tpm_buf_append(&buf, options->policydigest,
494                                options->policydigest_len);
495         } else {
496                 tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH);
497                 tpm_buf_append_u16(&buf, 0);
498         }
499
500         /* public parameters */
501         tpm_buf_append_u16(&buf, TPM2_ALG_NULL);
502         tpm_buf_append_u16(&buf, 0);
503
504         /* outside info */
505         tpm_buf_append_u16(&buf, 0);
506
507         /* creation PCR */
508         tpm_buf_append_u32(&buf, 0);
509
510         if (buf.flags & TPM_BUF_OVERFLOW) {
511                 rc = -E2BIG;
512                 goto out;
513         }
514
515         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, "sealing data");
516         if (rc)
517                 goto out;
518
519         blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]);
520         if (blob_len > MAX_BLOB_SIZE) {
521                 rc = -E2BIG;
522                 goto out;
523         }
524
525         memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len);
526         payload->blob_len = blob_len;
527
528 out:
529         tpm_buf_destroy(&buf);
530
531         if (rc > 0) {
532                 if (tpm2_rc_value(rc) == TPM2_RC_HASH)
533                         rc = -EINVAL;
534                 else
535                         rc = -EPERM;
536         }
537
538         return rc;
539 }
540
541 /**
542  * tpm2_load_cmd() - execute a TPM2_Load command
543  * @chip_num: TPM chip to use
544  * @payload: the key data in clear and encrypted form
545  * @options: authentication values and other options
546  *
547  * Return: same as with tpm_transmit_cmd
548  */
549 static int tpm2_load_cmd(struct tpm_chip *chip,
550                          struct trusted_key_payload *payload,
551                          struct trusted_key_options *options,
552                          u32 *blob_handle, unsigned int flags)
553 {
554         struct tpm_buf buf;
555         unsigned int private_len;
556         unsigned int public_len;
557         unsigned int blob_len;
558         int rc;
559
560         private_len = be16_to_cpup((__be16 *) &payload->blob[0]);
561         if (private_len > (payload->blob_len - 2))
562                 return -E2BIG;
563
564         public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]);
565         blob_len = private_len + public_len + 4;
566         if (blob_len > payload->blob_len)
567                 return -E2BIG;
568
569         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
570         if (rc)
571                 return rc;
572
573         tpm_buf_append_u32(&buf, options->keyhandle);
574         tpm2_buf_append_auth(&buf, TPM2_RS_PW,
575                              NULL /* nonce */, 0,
576                              0 /* session_attributes */,
577                              options->keyauth /* hmac */,
578                              TPM_DIGEST_SIZE);
579
580         tpm_buf_append(&buf, payload->blob, blob_len);
581
582         if (buf.flags & TPM_BUF_OVERFLOW) {
583                 rc = -E2BIG;
584                 goto out;
585         }
586
587         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "loading blob");
588         if (!rc)
589                 *blob_handle = be32_to_cpup(
590                         (__be32 *) &buf.data[TPM_HEADER_SIZE]);
591
592 out:
593         tpm_buf_destroy(&buf);
594
595         if (rc > 0)
596                 rc = -EPERM;
597
598         return rc;
599 }
600
601 /**
602  * tpm2_flush_context_cmd() - execute a TPM2_FlushContext command
603  * @chip_num: TPM chip to use
604  * @payload: the key data in clear and encrypted form
605  * @options: authentication values and other options
606  *
607  * Return: same as with tpm_transmit_cmd
608  */
609 static void tpm2_flush_context_cmd(struct tpm_chip *chip, u32 handle,
610                                    unsigned int flags)
611 {
612         struct tpm_buf buf;
613         int rc;
614
615         rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT);
616         if (rc) {
617                 dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n",
618                          handle);
619                 return;
620         }
621
622         tpm_buf_append_u32(&buf, handle);
623
624         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags,
625                               "flushing context");
626         if (rc)
627                 dev_warn(&chip->dev, "0x%08x was not flushed, rc=%d\n", handle,
628                          rc);
629
630         tpm_buf_destroy(&buf);
631 }
632
633 /**
634  * tpm2_unseal_cmd() - execute a TPM2_Unload command
635  * @chip_num: TPM chip to use
636  * @payload: the key data in clear and encrypted form
637  * @options: authentication values and other options
638  *
639  * Return: same as with tpm_transmit_cmd
640  */
641 static int tpm2_unseal_cmd(struct tpm_chip *chip,
642                            struct trusted_key_payload *payload,
643                            struct trusted_key_options *options,
644                            u32 blob_handle, unsigned int flags)
645 {
646         struct tpm_buf buf;
647         u16 data_len;
648         u8 *data;
649         int rc;
650
651         rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
652         if (rc)
653                 return rc;
654
655         tpm_buf_append_u32(&buf, blob_handle);
656         tpm2_buf_append_auth(&buf,
657                              options->policyhandle ?
658                              options->policyhandle : TPM2_RS_PW,
659                              NULL /* nonce */, 0,
660                              TPM2_SA_CONTINUE_SESSION,
661                              options->blobauth /* hmac */,
662                              TPM_DIGEST_SIZE);
663
664         rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, flags, "unsealing");
665         if (rc > 0)
666                 rc = -EPERM;
667
668         if (!rc) {
669                 data_len = be16_to_cpup(
670                         (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]);
671                 if (data_len < MIN_KEY_SIZE ||  data_len > MAX_KEY_SIZE + 1) {
672                         rc = -EFAULT;
673                         goto out;
674                 }
675
676                 data = &buf.data[TPM_HEADER_SIZE + 6];
677
678                 memcpy(payload->key, data, data_len - 1);
679                 payload->key_len = data_len - 1;
680                 payload->migratable = data[data_len - 1];
681         }
682
683 out:
684         tpm_buf_destroy(&buf);
685         return rc;
686 }
687
688 /**
689  * tpm_unseal_trusted() - unseal the payload of a trusted key
690  * @chip_num: TPM chip to use
691  * @payload: the key data in clear and encrypted form
692  * @options: authentication values and other options
693  *
694  * Return: < 0 on error and 0 on success.
695  */
696 int tpm2_unseal_trusted(struct tpm_chip *chip,
697                         struct trusted_key_payload *payload,
698                         struct trusted_key_options *options)
699 {
700         u32 blob_handle;
701         int rc;
702
703         mutex_lock(&chip->tpm_mutex);
704         rc = tpm2_load_cmd(chip, payload, options, &blob_handle,
705                            TPM_TRANSMIT_UNLOCKED);
706         if (rc)
707                 goto out;
708
709         rc = tpm2_unseal_cmd(chip, payload, options, blob_handle,
710                              TPM_TRANSMIT_UNLOCKED);
711         tpm2_flush_context_cmd(chip, blob_handle, TPM_TRANSMIT_UNLOCKED);
712 out:
713         mutex_unlock(&chip->tpm_mutex);
714         return rc;
715 }
716
717 /**
718  * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
719  * @chip:               TPM chip to use.
720  * @property_id:        property ID.
721  * @value:              output variable.
722  * @desc:               passed to tpm_transmit_cmd()
723  *
724  * 0 is returned when the operation is successful. If a negative number is
725  * returned it remarks a POSIX error code. If a positive number is returned
726  * it remarks a TPM error.
727  */
728 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
729                         const char *desc)
730 {
731         struct tpm2_cmd cmd;
732         int rc;
733
734         cmd.header.in = tpm2_get_tpm_pt_header;
735         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
736         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(property_id);
737         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
738
739         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, desc);
740         if (!rc)
741                 *value = be32_to_cpu(cmd.params.get_tpm_pt_out.value);
742
743         return rc;
744 }
745 EXPORT_SYMBOL_GPL(tpm2_get_tpm_pt);
746
747 #define TPM2_STARTUP_IN_SIZE \
748         (sizeof(struct tpm_input_header) + \
749          sizeof(struct tpm2_startup_in))
750
751 static const struct tpm_input_header tpm2_startup_header = {
752         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
753         .length = cpu_to_be32(TPM2_STARTUP_IN_SIZE),
754         .ordinal = cpu_to_be32(TPM2_CC_STARTUP)
755 };
756
757 /**
758  * tpm2_startup() - send startup command to the TPM chip
759  * @chip:               TPM chip to use.
760  * @startup_type        startup type. The value is either
761  *                      TPM_SU_CLEAR or TPM_SU_STATE.
762  *
763  * 0 is returned when the operation is successful. If a negative number is
764  * returned it remarks a POSIX error code. If a positive number is returned
765  * it remarks a TPM error.
766  */
767 static int tpm2_startup(struct tpm_chip *chip, u16 startup_type)
768 {
769         struct tpm2_cmd cmd;
770
771         cmd.header.in = tpm2_startup_header;
772
773         cmd.params.startup_in.startup_type = cpu_to_be16(startup_type);
774         return tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0,
775                                 "attempting to start the TPM");
776 }
777
778 #define TPM2_SHUTDOWN_IN_SIZE \
779         (sizeof(struct tpm_input_header) + \
780          sizeof(struct tpm2_startup_in))
781
782 static const struct tpm_input_header tpm2_shutdown_header = {
783         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
784         .length = cpu_to_be32(TPM2_SHUTDOWN_IN_SIZE),
785         .ordinal = cpu_to_be32(TPM2_CC_SHUTDOWN)
786 };
787
788 /**
789  * tpm2_shutdown() - send shutdown command to the TPM chip
790  * @chip:               TPM chip to use.
791  * @shutdown_type       shutdown type. The value is either
792  *                      TPM_SU_CLEAR or TPM_SU_STATE.
793  */
794 void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
795 {
796         struct tpm2_cmd cmd;
797         int rc;
798
799         cmd.header.in = tpm2_shutdown_header;
800         cmd.params.startup_in.startup_type = cpu_to_be16(shutdown_type);
801
802         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, "stopping the TPM");
803
804         /* In places where shutdown command is sent there's no much we can do
805          * except print the error code on a system failure.
806          */
807         if (rc < 0)
808                 dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
809                          rc);
810 }
811
812 /*
813  * tpm2_calc_ordinal_duration() - maximum duration for a command
814  * @chip:       TPM chip to use.
815  * @ordinal:    command code number.
816  *
817  * 0 is returned when the operation is successful. If a negative number is
818  * returned it remarks a POSIX error code. If a positive number is returned
819  * it remarks a TPM error.
820  */
821 unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
822 {
823         int index = TPM_UNDEFINED;
824         int duration = 0;
825
826         if (ordinal >= TPM2_CC_FIRST && ordinal <= TPM2_CC_LAST)
827                 index = tpm2_ordinal_duration[ordinal - TPM2_CC_FIRST];
828
829         if (index != TPM_UNDEFINED)
830                 duration = chip->duration[index];
831
832         if (duration <= 0)
833                 duration = 2 * 60 * HZ;
834
835         return duration;
836 }
837 EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration);
838
839 #define TPM2_SELF_TEST_IN_SIZE \
840         (sizeof(struct tpm_input_header) + \
841          sizeof(struct tpm2_self_test_in))
842
843 static const struct tpm_input_header tpm2_selftest_header = {
844         .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
845         .length = cpu_to_be32(TPM2_SELF_TEST_IN_SIZE),
846         .ordinal = cpu_to_be32(TPM2_CC_SELF_TEST)
847 };
848
849 /**
850  * tpm2_continue_selftest() - start a self test
851  * @chip: TPM chip to use
852  * @full: test all commands instead of testing only those that were not
853  *        previously tested.
854  *
855  * 0 is returned when the operation is successful. If a negative number is
856  * returned it remarks a POSIX error code. If a positive number is returned
857  * it remarks a TPM error.
858  */
859 static int tpm2_start_selftest(struct tpm_chip *chip, bool full)
860 {
861         int rc;
862         struct tpm2_cmd cmd;
863
864         cmd.header.in = tpm2_selftest_header;
865         cmd.params.selftest_in.full_test = full;
866
867         rc = tpm_transmit_cmd(chip, &cmd, TPM2_SELF_TEST_IN_SIZE, 0,
868                               "continue selftest");
869
870         /* At least some prototype chips seem to give RC_TESTING error
871          * immediately. This is a workaround for that.
872          */
873         if (rc == TPM2_RC_TESTING) {
874                 dev_warn(&chip->dev, "Got RC_TESTING, ignoring\n");
875                 rc = 0;
876         }
877
878         return rc;
879 }
880
881 /**
882  * tpm2_do_selftest() - run a full self test
883  * @chip: TPM chip to use
884  *
885  * During the self test TPM2 commands return with the error code RC_TESTING.
886  * Waiting is done by issuing PCR read until it executes successfully.
887  *
888  * 0 is returned when the operation is successful. If a negative number is
889  * returned it remarks a POSIX error code. If a positive number is returned
890  * it remarks a TPM error.
891  */
892 static int tpm2_do_selftest(struct tpm_chip *chip)
893 {
894         int rc;
895         unsigned int loops;
896         unsigned int delay_msec = 100;
897         unsigned long duration;
898         struct tpm2_cmd cmd;
899         int i;
900
901         duration = tpm2_calc_ordinal_duration(chip, TPM2_CC_SELF_TEST);
902
903         loops = jiffies_to_msecs(duration) / delay_msec;
904
905         rc = tpm2_start_selftest(chip, true);
906         if (rc)
907                 return rc;
908
909         for (i = 0; i < loops; i++) {
910                 /* Attempt to read a PCR value */
911                 cmd.header.in = tpm2_pcrread_header;
912                 cmd.params.pcrread_in.pcr_selects_cnt = cpu_to_be32(1);
913                 cmd.params.pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1);
914                 cmd.params.pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN;
915                 cmd.params.pcrread_in.pcr_select[0] = 0x01;
916                 cmd.params.pcrread_in.pcr_select[1] = 0x00;
917                 cmd.params.pcrread_in.pcr_select[2] = 0x00;
918
919                 rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), 0, NULL);
920                 if (rc < 0)
921                         break;
922
923                 rc = be32_to_cpu(cmd.header.out.return_code);
924                 if (rc != TPM2_RC_TESTING)
925                         break;
926
927                 msleep(delay_msec);
928         }
929
930         return rc;
931 }
932
933 /**
934  * tpm2_probe() - probe TPM 2.0
935  * @chip: TPM chip to use
936  *
937  * Send idempotent TPM 2.0 command and see whether TPM 2.0 chip replied based on
938  * the reply tag.
939  */
940 int tpm2_probe(struct tpm_chip *chip)
941 {
942         struct tpm2_cmd cmd;
943         int rc;
944
945         cmd.header.in = tpm2_get_tpm_pt_header;
946         cmd.params.get_tpm_pt_in.cap_id = cpu_to_be32(TPM2_CAP_TPM_PROPERTIES);
947         cmd.params.get_tpm_pt_in.property_id = cpu_to_be32(0x100);
948         cmd.params.get_tpm_pt_in.property_cnt = cpu_to_be32(1);
949
950         rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd),  0, NULL);
951         if (rc <  0)
952                 return rc;
953
954         if (be16_to_cpu(cmd.header.out.tag) == TPM2_ST_NO_SESSIONS)
955                 chip->flags |= TPM_CHIP_FLAG_TPM2;
956
957         return 0;
958 }
959 EXPORT_SYMBOL_GPL(tpm2_probe);
960
961 /**
962  * tpm2_auto_startup - Perform the standard automatic TPM initialization
963  *                     sequence
964  * @chip: TPM chip to use
965  *
966  * Returns 0 on success, < 0 in case of fatal error.
967  */
968 int tpm2_auto_startup(struct tpm_chip *chip)
969 {
970         int rc;
971
972         rc = tpm_get_timeouts(chip);
973         if (rc)
974                 goto out;
975
976         rc = tpm2_do_selftest(chip);
977         if (rc != 0 && rc != TPM2_RC_INITIALIZE) {
978                 dev_err(&chip->dev, "TPM self test failed\n");
979                 goto out;
980         }
981
982         if (rc == TPM2_RC_INITIALIZE) {
983                 rc = tpm2_startup(chip, TPM2_SU_CLEAR);
984                 if (rc)
985                         goto out;
986
987                 rc = tpm2_do_selftest(chip);
988                 if (rc) {
989                         dev_err(&chip->dev, "TPM self test failed\n");
990                         goto out;
991                 }
992         }
993
994 out:
995         if (rc > 0)
996                 rc = -ENODEV;
997         return rc;
998 }