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/sha1.h>
26 #include <linux/capability.h>
27 #include <linux/tpm.h>
28 #include <linux/tpm_command.h>
30 #include <keys/trusted_tpm.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);
71 kfree_sensitive(sdesc);
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);
115 kfree_sensitive(sdesc);
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);
169 kfree_sensitive(sdesc);
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))
254 kfree_sensitive(sdesc);
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))
356 kfree_sensitive(sdesc);
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);
409 if (ret != TPM_NONCE_SIZE)
412 tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OSAP);
413 tpm_buf_append_u16(tb, type);
414 tpm_buf_append_u32(tb, handle);
415 tpm_buf_append(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)
440 tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OIAP);
441 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
445 *handle = LOAD32(tb->data, TPM_DATA_OFFSET);
446 memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
450 EXPORT_SYMBOL_GPL(oiap);
453 unsigned char encauth[SHA1_DIGEST_SIZE];
454 unsigned char pubauth[SHA1_DIGEST_SIZE];
455 unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
456 unsigned char xorhash[SHA1_DIGEST_SIZE];
457 unsigned char nonceodd[TPM_NONCE_SIZE];
461 * Have the TPM seal(encrypt) the trusted key, possibly based on
462 * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
464 static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
465 uint32_t keyhandle, const unsigned char *keyauth,
466 const unsigned char *data, uint32_t datalen,
467 unsigned char *blob, uint32_t *bloblen,
468 const unsigned char *blobauth,
469 const unsigned char *pcrinfo, uint32_t pcrinfosize)
471 struct osapsess sess;
472 struct tpm_digests *td;
483 /* alloc some work space for all the hashes */
484 td = kmalloc(sizeof *td, GFP_KERNEL);
488 /* get session for sealing key */
489 ret = osap(tb, &sess, keyauth, keytype, keyhandle);
494 /* calculate encrypted authorization value */
495 memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
496 memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
497 ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
501 ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
505 if (ret != TPM_NONCE_SIZE)
508 ordinal = htonl(TPM_ORD_SEAL);
509 datsize = htonl(datalen);
510 pcrsize = htonl(pcrinfosize);
513 /* encrypt data authorization key */
514 for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
515 td->encauth[i] = td->xorhash[i] ^ blobauth[i];
517 /* calculate authorization HMAC value */
518 if (pcrinfosize == 0) {
519 /* no pcr info specified */
520 ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
521 sess.enonce, td->nonceodd, cont,
522 sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
523 td->encauth, sizeof(uint32_t), &pcrsize,
524 sizeof(uint32_t), &datsize, datalen, data, 0,
527 /* pcr info specified */
528 ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
529 sess.enonce, td->nonceodd, cont,
530 sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
531 td->encauth, sizeof(uint32_t), &pcrsize,
532 pcrinfosize, pcrinfo, sizeof(uint32_t),
533 &datsize, datalen, data, 0, 0);
538 /* build and send the TPM request packet */
539 tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_SEAL);
540 tpm_buf_append_u32(tb, keyhandle);
541 tpm_buf_append(tb, td->encauth, SHA1_DIGEST_SIZE);
542 tpm_buf_append_u32(tb, pcrinfosize);
543 tpm_buf_append(tb, pcrinfo, pcrinfosize);
544 tpm_buf_append_u32(tb, datalen);
545 tpm_buf_append(tb, data, datalen);
546 tpm_buf_append_u32(tb, sess.handle);
547 tpm_buf_append(tb, td->nonceodd, TPM_NONCE_SIZE);
548 tpm_buf_append_u8(tb, cont);
549 tpm_buf_append(tb, td->pubauth, SHA1_DIGEST_SIZE);
551 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
555 /* calculate the size of the returned Blob */
556 sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
557 encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
558 sizeof(uint32_t) + sealinfosize);
559 storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
560 sizeof(uint32_t) + encdatasize;
562 /* check the HMAC in the response */
563 ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
564 SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
567 /* copy the returned blob to caller */
569 memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
570 *bloblen = storedsize;
578 * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
580 static int tpm_unseal(struct tpm_buf *tb,
581 uint32_t keyhandle, const unsigned char *keyauth,
582 const unsigned char *blob, int bloblen,
583 const unsigned char *blobauth,
584 unsigned char *data, unsigned int *datalen)
586 unsigned char nonceodd[TPM_NONCE_SIZE];
587 unsigned char enonce1[TPM_NONCE_SIZE];
588 unsigned char enonce2[TPM_NONCE_SIZE];
589 unsigned char authdata1[SHA1_DIGEST_SIZE];
590 unsigned char authdata2[SHA1_DIGEST_SIZE];
591 uint32_t authhandle1 = 0;
592 uint32_t authhandle2 = 0;
593 unsigned char cont = 0;
597 /* sessions for unsealing key and data */
598 ret = oiap(tb, &authhandle1, enonce1);
600 pr_info("trusted_key: oiap failed (%d)\n", ret);
603 ret = oiap(tb, &authhandle2, enonce2);
605 pr_info("trusted_key: oiap failed (%d)\n", ret);
609 ordinal = htonl(TPM_ORD_UNSEAL);
610 ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
614 if (ret != TPM_NONCE_SIZE) {
615 pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
618 ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
619 enonce1, nonceodd, cont, sizeof(uint32_t),
620 &ordinal, bloblen, blob, 0, 0);
623 ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
624 enonce2, nonceodd, cont, sizeof(uint32_t),
625 &ordinal, bloblen, blob, 0, 0);
629 /* build and send TPM request packet */
630 tpm_buf_reset(tb, TPM_TAG_RQU_AUTH2_COMMAND, TPM_ORD_UNSEAL);
631 tpm_buf_append_u32(tb, keyhandle);
632 tpm_buf_append(tb, blob, bloblen);
633 tpm_buf_append_u32(tb, authhandle1);
634 tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
635 tpm_buf_append_u8(tb, cont);
636 tpm_buf_append(tb, authdata1, SHA1_DIGEST_SIZE);
637 tpm_buf_append_u32(tb, authhandle2);
638 tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
639 tpm_buf_append_u8(tb, cont);
640 tpm_buf_append(tb, authdata2, SHA1_DIGEST_SIZE);
642 ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
644 pr_info("trusted_key: authhmac failed (%d)\n", ret);
648 *datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
649 ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
650 keyauth, SHA1_DIGEST_SIZE,
651 blobauth, SHA1_DIGEST_SIZE,
652 sizeof(uint32_t), TPM_DATA_OFFSET,
653 *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
656 pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
659 memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
664 * Have the TPM seal(encrypt) the symmetric key
666 static int key_seal(struct trusted_key_payload *p,
667 struct trusted_key_options *o)
672 ret = tpm_buf_init(&tb, 0, 0);
676 /* include migratable flag at end of sealed key */
677 p->key[p->key_len] = p->migratable;
679 ret = tpm_seal(&tb, o->keytype, o->keyhandle, o->keyauth,
680 p->key, p->key_len + 1, p->blob, &p->blob_len,
681 o->blobauth, o->pcrinfo, o->pcrinfo_len);
683 pr_info("trusted_key: srkseal failed (%d)\n", ret);
685 tpm_buf_destroy(&tb);
690 * Have the TPM unseal(decrypt) the symmetric key
692 static int key_unseal(struct trusted_key_payload *p,
693 struct trusted_key_options *o)
698 ret = tpm_buf_init(&tb, 0, 0);
702 ret = tpm_unseal(&tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
703 o->blobauth, p->key, &p->key_len);
705 pr_info("trusted_key: srkunseal failed (%d)\n", ret);
707 /* pull migratable flag out of sealed key */
708 p->migratable = p->key[--p->key_len];
710 tpm_buf_destroy(&tb);
716 Opt_new, Opt_load, Opt_update,
717 Opt_keyhandle, Opt_keyauth, Opt_blobauth,
718 Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
724 static const match_table_t key_tokens = {
727 {Opt_update, "update"},
728 {Opt_keyhandle, "keyhandle=%s"},
729 {Opt_keyauth, "keyauth=%s"},
730 {Opt_blobauth, "blobauth=%s"},
731 {Opt_pcrinfo, "pcrinfo=%s"},
732 {Opt_pcrlock, "pcrlock=%s"},
733 {Opt_migratable, "migratable=%s"},
734 {Opt_hash, "hash=%s"},
735 {Opt_policydigest, "policydigest=%s"},
736 {Opt_policyhandle, "policyhandle=%s"},
740 /* can have zero or more token= options */
741 static int getoptions(char *c, struct trusted_key_payload *pay,
742 struct trusted_key_options *opt)
744 substring_t args[MAX_OPT_ARGS];
748 unsigned long handle;
750 unsigned long token_mask = 0;
751 unsigned int digest_len;
755 tpm2 = tpm_is_tpm2(chip);
759 opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
761 while ((p = strsep(&c, " \t"))) {
762 if (*p == '\0' || *p == ' ' || *p == '\t')
764 token = match_token(p, key_tokens, args);
765 if (test_and_set_bit(token, &token_mask))
770 opt->pcrinfo_len = strlen(args[0].from) / 2;
771 if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
773 res = hex2bin(opt->pcrinfo, args[0].from,
779 res = kstrtoul(args[0].from, 16, &handle);
782 opt->keytype = SEAL_keytype;
783 opt->keyhandle = handle;
786 if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
788 res = hex2bin(opt->keyauth, args[0].from,
794 if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
796 res = hex2bin(opt->blobauth, args[0].from,
802 if (*args[0].from == '0')
804 else if (*args[0].from != '1')
808 res = kstrtoul(args[0].from, 10, &lock);
814 if (test_bit(Opt_policydigest, &token_mask))
816 for (i = 0; i < HASH_ALGO__LAST; i++) {
817 if (!strcmp(args[0].from, hash_algo_name[i])) {
822 if (i == HASH_ALGO__LAST)
824 if (!tpm2 && i != HASH_ALGO_SHA1) {
825 pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
829 case Opt_policydigest:
830 digest_len = hash_digest_size[opt->hash];
831 if (!tpm2 || strlen(args[0].from) != (2 * digest_len))
833 res = hex2bin(opt->policydigest, args[0].from,
837 opt->policydigest_len = digest_len;
839 case Opt_policyhandle:
842 res = kstrtoul(args[0].from, 16, &handle);
845 opt->policyhandle = handle;
855 * datablob_parse - parse the keyctl data and fill in the
856 * payload and options structures
858 * On success returns 0, otherwise -EINVAL.
860 static int datablob_parse(char *datablob, struct trusted_key_payload *p,
861 struct trusted_key_options *o)
863 substring_t args[MAX_OPT_ARGS];
870 c = strsep(&datablob, " \t");
873 key_cmd = match_token(c, key_tokens, args);
876 /* first argument is key size */
877 c = strsep(&datablob, " \t");
880 ret = kstrtol(c, 10, &keylen);
881 if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
884 ret = getoptions(datablob, p, o);
890 /* first argument is sealed blob */
891 c = strsep(&datablob, " \t");
894 p->blob_len = strlen(c) / 2;
895 if (p->blob_len > MAX_BLOB_SIZE)
897 ret = hex2bin(p->blob, c, p->blob_len);
900 ret = getoptions(datablob, p, o);
906 /* all arguments are options */
907 ret = getoptions(datablob, p, o);
919 static struct trusted_key_options *trusted_options_alloc(void)
921 struct trusted_key_options *options;
924 tpm2 = tpm_is_tpm2(chip);
928 options = kzalloc(sizeof *options, GFP_KERNEL);
930 /* set any non-zero defaults */
931 options->keytype = SRK_keytype;
934 options->keyhandle = SRKHANDLE;
939 static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
941 struct trusted_key_payload *p = NULL;
944 ret = key_payload_reserve(key, sizeof *p);
947 p = kzalloc(sizeof *p, GFP_KERNEL);
949 p->migratable = 1; /* migratable by default */
954 * trusted_instantiate - create a new trusted key
956 * Unseal an existing trusted blob or, for a new key, get a
957 * random key, then seal and create a trusted key-type key,
958 * adding it to the specified keyring.
960 * On success, return 0. Otherwise return errno.
962 static int trusted_instantiate(struct key *key,
963 struct key_preparsed_payload *prep)
965 struct trusted_key_payload *payload = NULL;
966 struct trusted_key_options *options = NULL;
967 size_t datalen = prep->datalen;
974 tpm2 = tpm_is_tpm2(chip);
978 if (datalen <= 0 || datalen > 32767 || !prep->data)
981 datablob = kmalloc(datalen + 1, GFP_KERNEL);
984 memcpy(datablob, prep->data, datalen);
985 datablob[datalen] = '\0';
987 options = trusted_options_alloc();
992 payload = trusted_payload_alloc(key);
998 key_cmd = datablob_parse(datablob, payload, options);
1004 if (!options->keyhandle) {
1009 dump_payload(payload);
1010 dump_options(options);
1015 ret = tpm2_unseal_trusted(chip, payload, options);
1017 ret = key_unseal(payload, options);
1018 dump_payload(payload);
1019 dump_options(options);
1021 pr_info("trusted_key: key_unseal failed (%d)\n", ret);
1024 key_len = payload->key_len;
1025 ret = tpm_get_random(chip, payload->key, key_len);
1029 if (ret != key_len) {
1030 pr_info("trusted_key: key_create failed (%d)\n", ret);
1035 ret = tpm2_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);
1048 kfree_sensitive(datablob);
1049 kfree_sensitive(options);
1051 rcu_assign_keypointer(key, payload);
1053 kfree_sensitive(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) {
1104 kfree_sensitive(new_p);
1108 if (!new_o->keyhandle) {
1110 kfree_sensitive(new_p);
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);
1124 kfree_sensitive(new_p);
1127 if (new_o->pcrlock) {
1128 ret = pcrlock(new_o->pcrlock);
1130 pr_info("trusted_key: pcrlock failed (%d)\n", ret);
1131 kfree_sensitive(new_p);
1135 rcu_assign_keypointer(key, new_p);
1136 call_rcu(&p->rcu, trusted_rcu_free);
1138 kfree_sensitive(datablob);
1139 kfree_sensitive(new_o);
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 kfree_sensitive(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");