1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2010 IBM Corporation
6 * David Safford <safford@us.ibm.com>
8 * See Documentation/security/keys/trusted-encrypted.rst
11 #include <crypto/hash_info.h>
12 #include <linux/uaccess.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <linux/parser.h>
17 #include <linux/string.h>
18 #include <linux/err.h>
19 #include <keys/user-type.h>
20 #include <keys/trusted-type.h>
21 #include <linux/key-type.h>
22 #include <linux/rcupdate.h>
23 #include <linux/crypto.h>
24 #include <crypto/hash.h>
25 #include <crypto/sha.h>
26 #include <linux/capability.h>
27 #include <linux/tpm.h>
28 #include <linux/tpm_command.h>
30 #include <keys/trusted.h>
32 static const char hmac_alg[] = "hmac(sha1)";
33 static const char hash_alg[] = "sha1";
34 static struct tpm_chip *chip;
35 static struct tpm_digest *digests;
38 struct shash_desc shash;
42 static struct crypto_shash *hashalg;
43 static struct crypto_shash *hmacalg;
45 static struct sdesc *init_sdesc(struct crypto_shash *alg)
50 size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
51 sdesc = kmalloc(size, GFP_KERNEL);
53 return ERR_PTR(-ENOMEM);
54 sdesc->shash.tfm = alg;
58 static int TSS_sha1(const unsigned char *data, unsigned int datalen,
59 unsigned char *digest)
64 sdesc = init_sdesc(hashalg);
66 pr_info("trusted_key: can't alloc %s\n", hash_alg);
67 return PTR_ERR(sdesc);
70 ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
75 static int TSS_rawhmac(unsigned char *digest, const unsigned char *key,
76 unsigned int keylen, ...)
84 sdesc = init_sdesc(hmacalg);
86 pr_info("trusted_key: can't alloc %s\n", hmac_alg);
87 return PTR_ERR(sdesc);
90 ret = crypto_shash_setkey(hmacalg, key, keylen);
93 ret = crypto_shash_init(&sdesc->shash);
97 va_start(argp, keylen);
99 dlen = va_arg(argp, unsigned int);
102 data = va_arg(argp, unsigned char *);
107 ret = crypto_shash_update(&sdesc->shash, data, dlen);
113 ret = crypto_shash_final(&sdesc->shash, digest);
120 * calculate authorization info fields to send to TPM
122 int TSS_authhmac(unsigned char *digest, const unsigned char *key,
123 unsigned int keylen, unsigned char *h1,
124 unsigned char *h2, unsigned int h3, ...)
126 unsigned char paramdigest[SHA1_DIGEST_SIZE];
137 sdesc = init_sdesc(hashalg);
139 pr_info("trusted_key: can't alloc %s\n", hash_alg);
140 return PTR_ERR(sdesc);
144 ret = crypto_shash_init(&sdesc->shash);
149 dlen = va_arg(argp, unsigned int);
152 data = va_arg(argp, unsigned char *);
157 ret = crypto_shash_update(&sdesc->shash, data, dlen);
163 ret = crypto_shash_final(&sdesc->shash, paramdigest);
165 ret = TSS_rawhmac(digest, key, keylen, SHA1_DIGEST_SIZE,
166 paramdigest, TPM_NONCE_SIZE, h1,
167 TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
172 EXPORT_SYMBOL_GPL(TSS_authhmac);
175 * verify the AUTH1_COMMAND (Seal) result from TPM
177 int TSS_checkhmac1(unsigned char *buffer,
178 const uint32_t command,
179 const unsigned char *ononce,
180 const unsigned char *key,
181 unsigned int keylen, ...)
187 unsigned char *enonce;
188 unsigned char *continueflag;
189 unsigned char *authdata;
190 unsigned char testhmac[SHA1_DIGEST_SIZE];
191 unsigned char paramdigest[SHA1_DIGEST_SIZE];
201 bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
202 tag = LOAD16(buffer, 0);
204 result = LOAD32N(buffer, TPM_RETURN_OFFSET);
205 if (tag == TPM_TAG_RSP_COMMAND)
207 if (tag != TPM_TAG_RSP_AUTH1_COMMAND)
209 authdata = buffer + bufsize - SHA1_DIGEST_SIZE;
210 continueflag = authdata - 1;
211 enonce = continueflag - TPM_NONCE_SIZE;
213 sdesc = init_sdesc(hashalg);
215 pr_info("trusted_key: can't alloc %s\n", hash_alg);
216 return PTR_ERR(sdesc);
218 ret = crypto_shash_init(&sdesc->shash);
221 ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
225 ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
229 va_start(argp, keylen);
231 dlen = va_arg(argp, unsigned int);
234 dpos = va_arg(argp, unsigned int);
235 ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
241 ret = crypto_shash_final(&sdesc->shash, paramdigest);
245 ret = TSS_rawhmac(testhmac, key, keylen, SHA1_DIGEST_SIZE, paramdigest,
246 TPM_NONCE_SIZE, enonce, TPM_NONCE_SIZE, ononce,
247 1, continueflag, 0, 0);
251 if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
257 EXPORT_SYMBOL_GPL(TSS_checkhmac1);
260 * verify the AUTH2_COMMAND (unseal) result from TPM
262 static int TSS_checkhmac2(unsigned char *buffer,
263 const uint32_t command,
264 const unsigned char *ononce,
265 const unsigned char *key1,
266 unsigned int keylen1,
267 const unsigned char *key2,
268 unsigned int keylen2, ...)
274 unsigned char *enonce1;
275 unsigned char *continueflag1;
276 unsigned char *authdata1;
277 unsigned char *enonce2;
278 unsigned char *continueflag2;
279 unsigned char *authdata2;
280 unsigned char testhmac1[SHA1_DIGEST_SIZE];
281 unsigned char testhmac2[SHA1_DIGEST_SIZE];
282 unsigned char paramdigest[SHA1_DIGEST_SIZE];
289 bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
290 tag = LOAD16(buffer, 0);
292 result = LOAD32N(buffer, TPM_RETURN_OFFSET);
294 if (tag == TPM_TAG_RSP_COMMAND)
296 if (tag != TPM_TAG_RSP_AUTH2_COMMAND)
298 authdata1 = buffer + bufsize - (SHA1_DIGEST_SIZE + 1
299 + SHA1_DIGEST_SIZE + SHA1_DIGEST_SIZE);
300 authdata2 = buffer + bufsize - (SHA1_DIGEST_SIZE);
301 continueflag1 = authdata1 - 1;
302 continueflag2 = authdata2 - 1;
303 enonce1 = continueflag1 - TPM_NONCE_SIZE;
304 enonce2 = continueflag2 - TPM_NONCE_SIZE;
306 sdesc = init_sdesc(hashalg);
308 pr_info("trusted_key: can't alloc %s\n", hash_alg);
309 return PTR_ERR(sdesc);
311 ret = crypto_shash_init(&sdesc->shash);
314 ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
318 ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
323 va_start(argp, keylen2);
325 dlen = va_arg(argp, unsigned int);
328 dpos = va_arg(argp, unsigned int);
329 ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
335 ret = crypto_shash_final(&sdesc->shash, paramdigest);
339 ret = TSS_rawhmac(testhmac1, key1, keylen1, SHA1_DIGEST_SIZE,
340 paramdigest, TPM_NONCE_SIZE, enonce1,
341 TPM_NONCE_SIZE, ononce, 1, continueflag1, 0, 0);
344 if (memcmp(testhmac1, authdata1, SHA1_DIGEST_SIZE)) {
348 ret = TSS_rawhmac(testhmac2, key2, keylen2, SHA1_DIGEST_SIZE,
349 paramdigest, TPM_NONCE_SIZE, enonce2,
350 TPM_NONCE_SIZE, ononce, 1, continueflag2, 0, 0);
353 if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
361 * For key specific tpm requests, we will generate and send our
362 * own TPM command packets using the drivers send function.
364 int trusted_tpm_send(unsigned char *cmd, size_t buflen)
372 rc = tpm_send(chip, cmd, buflen);
375 /* Can't return positive return codes values to keyctl */
379 EXPORT_SYMBOL_GPL(trusted_tpm_send);
382 * Lock a trusted key, by extending a selected PCR.
384 * Prevents a trusted key that is sealed to PCRs from being accessed.
385 * This uses the tpm driver's extend function.
387 static int pcrlock(const int pcrnum)
389 if (!capable(CAP_SYS_ADMIN))
392 return tpm_pcr_extend(chip, pcrnum, digests) ? -EINVAL : 0;
396 * Create an object specific authorisation protocol (OSAP) session
398 static int osap(struct tpm_buf *tb, struct osapsess *s,
399 const unsigned char *key, uint16_t type, uint32_t handle)
401 unsigned char enonce[TPM_NONCE_SIZE];
402 unsigned char ononce[TPM_NONCE_SIZE];
405 ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE);
406 if (ret != TPM_NONCE_SIZE)
410 store16(tb, TPM_TAG_RQU_COMMAND);
411 store32(tb, TPM_OSAP_SIZE);
412 store32(tb, TPM_ORD_OSAP);
415 storebytes(tb, ononce, TPM_NONCE_SIZE);
417 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
421 s->handle = LOAD32(tb->data, TPM_DATA_OFFSET);
422 memcpy(s->enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)]),
424 memcpy(enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t) +
425 TPM_NONCE_SIZE]), TPM_NONCE_SIZE);
426 return TSS_rawhmac(s->secret, key, SHA1_DIGEST_SIZE, TPM_NONCE_SIZE,
427 enonce, TPM_NONCE_SIZE, ononce, 0, 0);
431 * Create an object independent authorisation protocol (oiap) session
433 int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
441 store16(tb, TPM_TAG_RQU_COMMAND);
442 store32(tb, TPM_OIAP_SIZE);
443 store32(tb, TPM_ORD_OIAP);
444 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
448 *handle = LOAD32(tb->data, TPM_DATA_OFFSET);
449 memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
453 EXPORT_SYMBOL_GPL(oiap);
456 unsigned char encauth[SHA1_DIGEST_SIZE];
457 unsigned char pubauth[SHA1_DIGEST_SIZE];
458 unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
459 unsigned char xorhash[SHA1_DIGEST_SIZE];
460 unsigned char nonceodd[TPM_NONCE_SIZE];
464 * Have the TPM seal(encrypt) the trusted key, possibly based on
465 * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
467 static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
468 uint32_t keyhandle, const unsigned char *keyauth,
469 const unsigned char *data, uint32_t datalen,
470 unsigned char *blob, uint32_t *bloblen,
471 const unsigned char *blobauth,
472 const unsigned char *pcrinfo, uint32_t pcrinfosize)
474 struct osapsess sess;
475 struct tpm_digests *td;
486 /* alloc some work space for all the hashes */
487 td = kmalloc(sizeof *td, GFP_KERNEL);
491 /* get session for sealing key */
492 ret = osap(tb, &sess, keyauth, keytype, keyhandle);
497 /* calculate encrypted authorization value */
498 memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
499 memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
500 ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
504 ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
505 if (ret != TPM_NONCE_SIZE)
507 ordinal = htonl(TPM_ORD_SEAL);
508 datsize = htonl(datalen);
509 pcrsize = htonl(pcrinfosize);
512 /* encrypt data authorization key */
513 for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
514 td->encauth[i] = td->xorhash[i] ^ blobauth[i];
516 /* calculate authorization HMAC value */
517 if (pcrinfosize == 0) {
518 /* no pcr info specified */
519 ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
520 sess.enonce, td->nonceodd, cont,
521 sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
522 td->encauth, sizeof(uint32_t), &pcrsize,
523 sizeof(uint32_t), &datsize, datalen, data, 0,
526 /* pcr info specified */
527 ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
528 sess.enonce, td->nonceodd, cont,
529 sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
530 td->encauth, sizeof(uint32_t), &pcrsize,
531 pcrinfosize, pcrinfo, sizeof(uint32_t),
532 &datsize, datalen, data, 0, 0);
537 /* build and send the TPM request packet */
539 store16(tb, TPM_TAG_RQU_AUTH1_COMMAND);
540 store32(tb, TPM_SEAL_SIZE + pcrinfosize + datalen);
541 store32(tb, TPM_ORD_SEAL);
542 store32(tb, keyhandle);
543 storebytes(tb, td->encauth, SHA1_DIGEST_SIZE);
544 store32(tb, pcrinfosize);
545 storebytes(tb, pcrinfo, pcrinfosize);
546 store32(tb, datalen);
547 storebytes(tb, data, datalen);
548 store32(tb, sess.handle);
549 storebytes(tb, td->nonceodd, TPM_NONCE_SIZE);
551 storebytes(tb, td->pubauth, SHA1_DIGEST_SIZE);
553 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
557 /* calculate the size of the returned Blob */
558 sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
559 encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
560 sizeof(uint32_t) + sealinfosize);
561 storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
562 sizeof(uint32_t) + encdatasize;
564 /* check the HMAC in the response */
565 ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
566 SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
569 /* copy the returned blob to caller */
571 memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
572 *bloblen = storedsize;
580 * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
582 static int tpm_unseal(struct tpm_buf *tb,
583 uint32_t keyhandle, const unsigned char *keyauth,
584 const unsigned char *blob, int bloblen,
585 const unsigned char *blobauth,
586 unsigned char *data, unsigned int *datalen)
588 unsigned char nonceodd[TPM_NONCE_SIZE];
589 unsigned char enonce1[TPM_NONCE_SIZE];
590 unsigned char enonce2[TPM_NONCE_SIZE];
591 unsigned char authdata1[SHA1_DIGEST_SIZE];
592 unsigned char authdata2[SHA1_DIGEST_SIZE];
593 uint32_t authhandle1 = 0;
594 uint32_t authhandle2 = 0;
595 unsigned char cont = 0;
600 /* sessions for unsealing key and data */
601 ret = oiap(tb, &authhandle1, enonce1);
603 pr_info("trusted_key: oiap failed (%d)\n", ret);
606 ret = oiap(tb, &authhandle2, enonce2);
608 pr_info("trusted_key: oiap failed (%d)\n", ret);
612 ordinal = htonl(TPM_ORD_UNSEAL);
613 keyhndl = htonl(SRKHANDLE);
614 ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
615 if (ret != TPM_NONCE_SIZE) {
616 pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
619 ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
620 enonce1, nonceodd, cont, sizeof(uint32_t),
621 &ordinal, bloblen, blob, 0, 0);
624 ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
625 enonce2, nonceodd, cont, sizeof(uint32_t),
626 &ordinal, bloblen, blob, 0, 0);
630 /* build and send TPM request packet */
632 store16(tb, TPM_TAG_RQU_AUTH2_COMMAND);
633 store32(tb, TPM_UNSEAL_SIZE + bloblen);
634 store32(tb, TPM_ORD_UNSEAL);
635 store32(tb, keyhandle);
636 storebytes(tb, blob, bloblen);
637 store32(tb, authhandle1);
638 storebytes(tb, nonceodd, TPM_NONCE_SIZE);
640 storebytes(tb, authdata1, SHA1_DIGEST_SIZE);
641 store32(tb, authhandle2);
642 storebytes(tb, nonceodd, TPM_NONCE_SIZE);
644 storebytes(tb, authdata2, SHA1_DIGEST_SIZE);
646 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
648 pr_info("trusted_key: authhmac failed (%d)\n", ret);
652 *datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
653 ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
654 keyauth, SHA1_DIGEST_SIZE,
655 blobauth, SHA1_DIGEST_SIZE,
656 sizeof(uint32_t), TPM_DATA_OFFSET,
657 *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
660 pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
663 memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
668 * Have the TPM seal(encrypt) the symmetric key
670 static int key_seal(struct trusted_key_payload *p,
671 struct trusted_key_options *o)
676 tb = kzalloc(sizeof *tb, GFP_KERNEL);
680 /* include migratable flag at end of sealed key */
681 p->key[p->key_len] = p->migratable;
683 ret = tpm_seal(tb, o->keytype, o->keyhandle, o->keyauth,
684 p->key, p->key_len + 1, p->blob, &p->blob_len,
685 o->blobauth, o->pcrinfo, o->pcrinfo_len);
687 pr_info("trusted_key: srkseal failed (%d)\n", ret);
694 * Have the TPM unseal(decrypt) the symmetric key
696 static int key_unseal(struct trusted_key_payload *p,
697 struct trusted_key_options *o)
702 tb = kzalloc(sizeof *tb, GFP_KERNEL);
706 ret = tpm_unseal(tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
707 o->blobauth, p->key, &p->key_len);
709 pr_info("trusted_key: srkunseal failed (%d)\n", ret);
711 /* pull migratable flag out of sealed key */
712 p->migratable = p->key[--p->key_len];
720 Opt_new, Opt_load, Opt_update,
721 Opt_keyhandle, Opt_keyauth, Opt_blobauth,
722 Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
728 static const match_table_t key_tokens = {
731 {Opt_update, "update"},
732 {Opt_keyhandle, "keyhandle=%s"},
733 {Opt_keyauth, "keyauth=%s"},
734 {Opt_blobauth, "blobauth=%s"},
735 {Opt_pcrinfo, "pcrinfo=%s"},
736 {Opt_pcrlock, "pcrlock=%s"},
737 {Opt_migratable, "migratable=%s"},
738 {Opt_hash, "hash=%s"},
739 {Opt_policydigest, "policydigest=%s"},
740 {Opt_policyhandle, "policyhandle=%s"},
744 /* can have zero or more token= options */
745 static int getoptions(char *c, struct trusted_key_payload *pay,
746 struct trusted_key_options *opt)
748 substring_t args[MAX_OPT_ARGS];
752 unsigned long handle;
754 unsigned long token_mask = 0;
755 unsigned int digest_len;
759 tpm2 = tpm_is_tpm2(chip);
763 opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
765 while ((p = strsep(&c, " \t"))) {
766 if (*p == '\0' || *p == ' ' || *p == '\t')
768 token = match_token(p, key_tokens, args);
769 if (test_and_set_bit(token, &token_mask))
774 opt->pcrinfo_len = strlen(args[0].from) / 2;
775 if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
777 res = hex2bin(opt->pcrinfo, args[0].from,
783 res = kstrtoul(args[0].from, 16, &handle);
786 opt->keytype = SEAL_keytype;
787 opt->keyhandle = handle;
790 if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
792 res = hex2bin(opt->keyauth, args[0].from,
798 if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
800 res = hex2bin(opt->blobauth, args[0].from,
806 if (*args[0].from == '0')
808 else if (*args[0].from != '1')
812 res = kstrtoul(args[0].from, 10, &lock);
818 if (test_bit(Opt_policydigest, &token_mask))
820 for (i = 0; i < HASH_ALGO__LAST; i++) {
821 if (!strcmp(args[0].from, hash_algo_name[i])) {
826 if (i == HASH_ALGO__LAST)
828 if (!tpm2 && i != HASH_ALGO_SHA1) {
829 pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
833 case Opt_policydigest:
834 digest_len = hash_digest_size[opt->hash];
835 if (!tpm2 || strlen(args[0].from) != (2 * digest_len))
837 res = hex2bin(opt->policydigest, args[0].from,
841 opt->policydigest_len = digest_len;
843 case Opt_policyhandle:
846 res = kstrtoul(args[0].from, 16, &handle);
849 opt->policyhandle = handle;
859 * datablob_parse - parse the keyctl data and fill in the
860 * payload and options structures
862 * On success returns 0, otherwise -EINVAL.
864 static int datablob_parse(char *datablob, struct trusted_key_payload *p,
865 struct trusted_key_options *o)
867 substring_t args[MAX_OPT_ARGS];
874 c = strsep(&datablob, " \t");
877 key_cmd = match_token(c, key_tokens, args);
880 /* first argument is key size */
881 c = strsep(&datablob, " \t");
884 ret = kstrtol(c, 10, &keylen);
885 if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
888 ret = getoptions(datablob, p, o);
894 /* first argument is sealed blob */
895 c = strsep(&datablob, " \t");
898 p->blob_len = strlen(c) / 2;
899 if (p->blob_len > MAX_BLOB_SIZE)
901 ret = hex2bin(p->blob, c, p->blob_len);
904 ret = getoptions(datablob, p, o);
910 /* all arguments are options */
911 ret = getoptions(datablob, p, o);
923 static struct trusted_key_options *trusted_options_alloc(void)
925 struct trusted_key_options *options;
928 tpm2 = tpm_is_tpm2(chip);
932 options = kzalloc(sizeof *options, GFP_KERNEL);
934 /* set any non-zero defaults */
935 options->keytype = SRK_keytype;
938 options->keyhandle = SRKHANDLE;
943 static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
945 struct trusted_key_payload *p = NULL;
948 ret = key_payload_reserve(key, sizeof *p);
951 p = kzalloc(sizeof *p, GFP_KERNEL);
953 p->migratable = 1; /* migratable by default */
958 * trusted_instantiate - create a new trusted key
960 * Unseal an existing trusted blob or, for a new key, get a
961 * random key, then seal and create a trusted key-type key,
962 * adding it to the specified keyring.
964 * On success, return 0. Otherwise return errno.
966 static int trusted_instantiate(struct key *key,
967 struct key_preparsed_payload *prep)
969 struct trusted_key_payload *payload = NULL;
970 struct trusted_key_options *options = NULL;
971 size_t datalen = prep->datalen;
978 tpm2 = tpm_is_tpm2(chip);
982 if (datalen <= 0 || datalen > 32767 || !prep->data)
985 datablob = kmalloc(datalen + 1, GFP_KERNEL);
988 memcpy(datablob, prep->data, datalen);
989 datablob[datalen] = '\0';
991 options = trusted_options_alloc();
996 payload = trusted_payload_alloc(key);
1002 key_cmd = datablob_parse(datablob, payload, options);
1008 if (!options->keyhandle) {
1013 dump_payload(payload);
1014 dump_options(options);
1019 ret = tpm_unseal_trusted(chip, payload, options);
1021 ret = key_unseal(payload, options);
1022 dump_payload(payload);
1023 dump_options(options);
1025 pr_info("trusted_key: key_unseal failed (%d)\n", ret);
1028 key_len = payload->key_len;
1029 ret = tpm_get_random(chip, payload->key, key_len);
1030 if (ret != key_len) {
1031 pr_info("trusted_key: key_create failed (%d)\n", ret);
1035 ret = tpm_seal_trusted(chip, payload, options);
1037 ret = key_seal(payload, options);
1039 pr_info("trusted_key: key_seal failed (%d)\n", ret);
1045 if (!ret && options->pcrlock)
1046 ret = pcrlock(options->pcrlock);
1051 rcu_assign_keypointer(key, payload);
1057 static void trusted_rcu_free(struct rcu_head *rcu)
1059 struct trusted_key_payload *p;
1061 p = container_of(rcu, struct trusted_key_payload, rcu);
1066 * trusted_update - reseal an existing key with new PCR values
1068 static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
1070 struct trusted_key_payload *p;
1071 struct trusted_key_payload *new_p;
1072 struct trusted_key_options *new_o;
1073 size_t datalen = prep->datalen;
1077 if (key_is_negative(key))
1079 p = key->payload.data[0];
1082 if (datalen <= 0 || datalen > 32767 || !prep->data)
1085 datablob = kmalloc(datalen + 1, GFP_KERNEL);
1088 new_o = trusted_options_alloc();
1093 new_p = trusted_payload_alloc(key);
1099 memcpy(datablob, prep->data, datalen);
1100 datablob[datalen] = '\0';
1101 ret = datablob_parse(datablob, new_p, new_o);
1102 if (ret != Opt_update) {
1108 if (!new_o->keyhandle) {
1114 /* copy old key values, and reseal with new pcrs */
1115 new_p->migratable = p->migratable;
1116 new_p->key_len = p->key_len;
1117 memcpy(new_p->key, p->key, p->key_len);
1119 dump_payload(new_p);
1121 ret = key_seal(new_p, new_o);
1123 pr_info("trusted_key: key_seal failed (%d)\n", ret);
1127 if (new_o->pcrlock) {
1128 ret = pcrlock(new_o->pcrlock);
1130 pr_info("trusted_key: pcrlock failed (%d)\n", ret);
1135 rcu_assign_keypointer(key, new_p);
1136 call_rcu(&p->rcu, trusted_rcu_free);
1144 * trusted_read - copy the sealed blob data to userspace in hex.
1145 * On success, return to userspace the trusted key datablob size.
1147 static long trusted_read(const struct key *key, char *buffer,
1150 const struct trusted_key_payload *p;
1154 p = dereference_key_locked(key);
1158 if (buffer && buflen >= 2 * p->blob_len) {
1160 for (i = 0; i < p->blob_len; i++)
1161 bufp = hex_byte_pack(bufp, p->blob[i]);
1163 return 2 * p->blob_len;
1167 * trusted_destroy - clear and free the key's payload
1169 static void trusted_destroy(struct key *key)
1171 kzfree(key->payload.data[0]);
1174 struct key_type key_type_trusted = {
1176 .instantiate = trusted_instantiate,
1177 .update = trusted_update,
1178 .destroy = trusted_destroy,
1179 .describe = user_describe,
1180 .read = trusted_read,
1183 EXPORT_SYMBOL_GPL(key_type_trusted);
1185 static void trusted_shash_release(void)
1188 crypto_free_shash(hashalg);
1190 crypto_free_shash(hmacalg);
1193 static int __init trusted_shash_alloc(void)
1197 hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
1198 if (IS_ERR(hmacalg)) {
1199 pr_info("trusted_key: could not allocate crypto %s\n",
1201 return PTR_ERR(hmacalg);
1204 hashalg = crypto_alloc_shash(hash_alg, 0, 0);
1205 if (IS_ERR(hashalg)) {
1206 pr_info("trusted_key: could not allocate crypto %s\n",
1208 ret = PTR_ERR(hashalg);
1215 crypto_free_shash(hmacalg);
1219 static int __init init_digests(void)
1223 digests = kcalloc(chip->nr_allocated_banks, sizeof(*digests),
1228 for (i = 0; i < chip->nr_allocated_banks; i++)
1229 digests[i].alg_id = chip->allocated_banks[i].alg_id;
1234 static int __init init_trusted(void)
1238 /* encrypted_keys.ko depends on successful load of this module even if
1241 chip = tpm_default_chip();
1245 ret = init_digests();
1248 ret = trusted_shash_alloc();
1251 ret = register_key_type(&key_type_trusted);
1256 trusted_shash_release();
1260 put_device(&chip->dev);
1264 static void __exit cleanup_trusted(void)
1267 put_device(&chip->dev);
1269 trusted_shash_release();
1270 unregister_key_type(&key_type_trusted);
1274 late_initcall(init_trusted);
1275 module_exit(cleanup_trusted);
1277 MODULE_LICENSE("GPL");