KEYS: trusted: Create trusted keys subsystem

Move existing code to trusted keys subsystem. Also, rename files with
"tpm" as suffix which provides the underlying implementation.

Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

2 files changed, 1282 insertions, 0 deletions

diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile
new file mode 100644
index 000000000000..1a24680edc6a
--- /dev/null
+++ b/security/keys/trusted-keys/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for trusted keys
+#
+
+obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
+trusted-y += trusted_tpm1.o
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
new file mode 100644
index 000000000000..e3155fd08f5b
--- /dev/null
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -0,0 +1,1275 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Author:
+ * David Safford <safford@us.ibm.com>
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <crypto/hash_info.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <linux/key-type.h>
+#include <linux/rcupdate.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <linux/capability.h>
+#include <linux/tpm.h>
+#include <linux/tpm_command.h>
+
+#include <keys/trusted_tpm.h>
+
+static const char hmac_alg[] = "hmac(sha1)";
+static const char hash_alg[] = "sha1";
+static struct tpm_chip *chip;
+static struct tpm_digest *digests;
+
+struct sdesc {
+	struct shash_desc shash;
+	char ctx[];
+};
+
+static struct crypto_shash *hashalg;
+static struct crypto_shash *hmacalg;
+
+static struct sdesc *init_sdesc(struct crypto_shash *alg)
+{
+	struct sdesc *sdesc;
+	int size;
+
+	size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
+	sdesc = kmalloc(size, GFP_KERNEL);
+	if (!sdesc)
+		return ERR_PTR(-ENOMEM);
+	sdesc->shash.tfm = alg;
+	return sdesc;
+}
+
+static int TSS_sha1(const unsigned char *data, unsigned int datalen,
+		    unsigned char *digest)
+{
+	struct sdesc *sdesc;
+	int ret;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
+	kzfree(sdesc);
+	return ret;
+}
+
+static int TSS_rawhmac(unsigned char *digest, const unsigned char *key,
+		       unsigned int keylen, ...)
+{
+	struct sdesc *sdesc;
+	va_list argp;
+	unsigned int dlen;
+	unsigned char *data;
+	int ret;
+
+	sdesc = init_sdesc(hmacalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hmac_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	ret = crypto_shash_setkey(hmacalg, key, keylen);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+
+	va_start(argp, keylen);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		data = va_arg(argp, unsigned char *);
+		if (data == NULL) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = crypto_shash_update(&sdesc->shash, data, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, digest);
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * calculate authorization info fields to send to TPM
+ */
+int TSS_authhmac(unsigned char *digest, const unsigned char *key,
+			unsigned int keylen, unsigned char *h1,
+			unsigned char *h2, unsigned int h3, ...)
+{
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned char *data;
+	unsigned char c;
+	int ret;
+	va_list argp;
+
+	if (!chip)
+		return -ENODEV;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+
+	c = !!h3;
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	va_start(argp, h3);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		data = va_arg(argp, unsigned char *);
+		if (!data) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = crypto_shash_update(&sdesc->shash, data, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (!ret)
+		ret = TSS_rawhmac(digest, key, keylen, SHA1_DIGEST_SIZE,
+				  paramdigest, TPM_NONCE_SIZE, h1,
+				  TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
+out:
+	kzfree(sdesc);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(TSS_authhmac);
+
+/*
+ * verify the AUTH1_COMMAND (Seal) result from TPM
+ */
+int TSS_checkhmac1(unsigned char *buffer,
+			  const uint32_t command,
+			  const unsigned char *ononce,
+			  const unsigned char *key,
+			  unsigned int keylen, ...)
+{
+	uint32_t bufsize;
+	uint16_t tag;
+	uint32_t ordinal;
+	uint32_t result;
+	unsigned char *enonce;
+	unsigned char *continueflag;
+	unsigned char *authdata;
+	unsigned char testhmac[SHA1_DIGEST_SIZE];
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned int dpos;
+	va_list argp;
+	int ret;
+
+	if (!chip)
+		return -ENODEV;
+
+	bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+	tag = LOAD16(buffer, 0);
+	ordinal = command;
+	result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+	if (tag == TPM_TAG_RSP_COMMAND)
+		return 0;
+	if (tag != TPM_TAG_RSP_AUTH1_COMMAND)
+		return -EINVAL;
+	authdata = buffer + bufsize - SHA1_DIGEST_SIZE;
+	continueflag = authdata - 1;
+	enonce = continueflag - TPM_NONCE_SIZE;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+				  sizeof result);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+				  sizeof ordinal);
+	if (ret < 0)
+		goto out;
+	va_start(argp, keylen);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		dpos = va_arg(argp, unsigned int);
+		ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (ret < 0)
+		goto out;
+
+	ret = TSS_rawhmac(testhmac, key, keylen, SHA1_DIGEST_SIZE, paramdigest,
+			  TPM_NONCE_SIZE, enonce, TPM_NONCE_SIZE, ononce,
+			  1, continueflag, 0, 0);
+	if (ret < 0)
+		goto out;
+
+	if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
+		ret = -EINVAL;
+out:
+	kzfree(sdesc);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(TSS_checkhmac1);
+
+/*
+ * verify the AUTH2_COMMAND (unseal) result from TPM
+ */
+static int TSS_checkhmac2(unsigned char *buffer,
+			  const uint32_t command,
+			  const unsigned char *ononce,
+			  const unsigned char *key1,
+			  unsigned int keylen1,
+			  const unsigned char *key2,
+			  unsigned int keylen2, ...)
+{
+	uint32_t bufsize;
+	uint16_t tag;
+	uint32_t ordinal;
+	uint32_t result;
+	unsigned char *enonce1;
+	unsigned char *continueflag1;
+	unsigned char *authdata1;
+	unsigned char *enonce2;
+	unsigned char *continueflag2;
+	unsigned char *authdata2;
+	unsigned char testhmac1[SHA1_DIGEST_SIZE];
+	unsigned char testhmac2[SHA1_DIGEST_SIZE];
+	unsigned char paramdigest[SHA1_DIGEST_SIZE];
+	struct sdesc *sdesc;
+	unsigned int dlen;
+	unsigned int dpos;
+	va_list argp;
+	int ret;
+
+	bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+	tag = LOAD16(buffer, 0);
+	ordinal = command;
+	result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+
+	if (tag == TPM_TAG_RSP_COMMAND)
+		return 0;
+	if (tag != TPM_TAG_RSP_AUTH2_COMMAND)
+		return -EINVAL;
+	authdata1 = buffer + bufsize - (SHA1_DIGEST_SIZE + 1
+			+ SHA1_DIGEST_SIZE + SHA1_DIGEST_SIZE);
+	authdata2 = buffer + bufsize - (SHA1_DIGEST_SIZE);
+	continueflag1 = authdata1 - 1;
+	continueflag2 = authdata2 - 1;
+	enonce1 = continueflag1 - TPM_NONCE_SIZE;
+	enonce2 = continueflag2 - TPM_NONCE_SIZE;
+
+	sdesc = init_sdesc(hashalg);
+	if (IS_ERR(sdesc)) {
+		pr_info("trusted_key: can't alloc %s\n", hash_alg);
+		return PTR_ERR(sdesc);
+	}
+	ret = crypto_shash_init(&sdesc->shash);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+				  sizeof result);
+	if (ret < 0)
+		goto out;
+	ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+				  sizeof ordinal);
+	if (ret < 0)
+		goto out;
+
+	va_start(argp, keylen2);
+	for (;;) {
+		dlen = va_arg(argp, unsigned int);
+		if (dlen == 0)
+			break;
+		dpos = va_arg(argp, unsigned int);
+		ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+		if (ret < 0)
+			break;
+	}
+	va_end(argp);
+	if (!ret)
+		ret = crypto_shash_final(&sdesc->shash, paramdigest);
+	if (ret < 0)
+		goto out;
+
+	ret = TSS_rawhmac(testhmac1, key1, keylen1, SHA1_DIGEST_SIZE,
+			  paramdigest, TPM_NONCE_SIZE, enonce1,
+			  TPM_NONCE_SIZE, ononce, 1, continueflag1, 0, 0);
+	if (ret < 0)
+		goto out;
+	if (memcmp(testhmac1, authdata1, SHA1_DIGEST_SIZE)) {
+		ret = -EINVAL;
+		goto out;
+	}
+	ret = TSS_rawhmac(testhmac2, key2, keylen2, SHA1_DIGEST_SIZE,
+			  paramdigest, TPM_NONCE_SIZE, enonce2,
+			  TPM_NONCE_SIZE, ononce, 1, continueflag2, 0, 0);
+	if (ret < 0)
+		goto out;
+	if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
+		ret = -EINVAL;
+out:
+	kzfree(sdesc);
+	return ret;
+}
+
+/*
+ * For key specific tpm requests, we will generate and send our
+ * own TPM command packets using the drivers send function.
+ */
+int trusted_tpm_send(unsigned char *cmd, size_t buflen)
+{
+	int rc;
+
+	if (!chip)
+		return -ENODEV;
+
+	dump_tpm_buf(cmd);
+	rc = tpm_send(chip, cmd, buflen);
+	dump_tpm_buf(cmd);
+	if (rc > 0)
+		/* Can't return positive return codes values to keyctl */
+		rc = -EPERM;
+	return rc;
+}
+EXPORT_SYMBOL_GPL(trusted_tpm_send);
+
+/*
+ * Lock a trusted key, by extending a selected PCR.
+ *
+ * Prevents a trusted key that is sealed to PCRs from being accessed.
+ * This uses the tpm driver's extend function.
+ */
+static int pcrlock(const int pcrnum)
+{
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	return tpm_pcr_extend(chip, pcrnum, digests) ? -EINVAL : 0;
+}
+
+/*
+ * Create an object specific authorisation protocol (OSAP) session
+ */
+static int osap(struct tpm_buf *tb, struct osapsess *s,
+		const unsigned char *key, uint16_t type, uint32_t handle)
+{
+	unsigned char enonce[TPM_NONCE_SIZE];
+	unsigned char ononce[TPM_NONCE_SIZE];
+	int ret;
+
+	ret = tpm_get_random(chip, ononce, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE)
+		return ret;
+
+	tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OSAP);
+	tpm_buf_append_u16(tb, type);
+	tpm_buf_append_u32(tb, handle);
+	tpm_buf_append(tb, ononce, TPM_NONCE_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		return ret;
+
+	s->handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+	memcpy(s->enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)]),
+	       TPM_NONCE_SIZE);
+	memcpy(enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t) +
+				  TPM_NONCE_SIZE]), TPM_NONCE_SIZE);
+	return TSS_rawhmac(s->secret, key, SHA1_DIGEST_SIZE, TPM_NONCE_SIZE,
+			   enonce, TPM_NONCE_SIZE, ononce, 0, 0);
+}
+
+/*
+ * Create an object independent authorisation protocol (oiap) session
+ */
+int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
+{
+	int ret;
+
+	if (!chip)
+		return -ENODEV;
+
+	tpm_buf_reset(tb, TPM_TAG_RQU_COMMAND, TPM_ORD_OIAP);
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		return ret;
+
+	*handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+	memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
+	       TPM_NONCE_SIZE);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(oiap);
+
+struct tpm_digests {
+	unsigned char encauth[SHA1_DIGEST_SIZE];
+	unsigned char pubauth[SHA1_DIGEST_SIZE];
+	unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
+	unsigned char xorhash[SHA1_DIGEST_SIZE];
+	unsigned char nonceodd[TPM_NONCE_SIZE];
+};
+
+/*
+ * Have the TPM seal(encrypt) the trusted key, possibly based on
+ * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
+ */
+static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
+		    uint32_t keyhandle, const unsigned char *keyauth,
+		    const unsigned char *data, uint32_t datalen,
+		    unsigned char *blob, uint32_t *bloblen,
+		    const unsigned char *blobauth,
+		    const unsigned char *pcrinfo, uint32_t pcrinfosize)
+{
+	struct osapsess sess;
+	struct tpm_digests *td;
+	unsigned char cont;
+	uint32_t ordinal;
+	uint32_t pcrsize;
+	uint32_t datsize;
+	int sealinfosize;
+	int encdatasize;
+	int storedsize;
+	int ret;
+	int i;
+
+	/* alloc some work space for all the hashes */
+	td = kmalloc(sizeof *td, GFP_KERNEL);
+	if (!td)
+		return -ENOMEM;
+
+	/* get session for sealing key */
+	ret = osap(tb, &sess, keyauth, keytype, keyhandle);
+	if (ret < 0)
+		goto out;
+	dump_sess(&sess);
+
+	/* calculate encrypted authorization value */
+	memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
+	memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
+	ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
+	if (ret < 0)
+		goto out;
+
+	ret = tpm_get_random(chip, td->nonceodd, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE)
+		goto out;
+	ordinal = htonl(TPM_ORD_SEAL);
+	datsize = htonl(datalen);
+	pcrsize = htonl(pcrinfosize);
+	cont = 0;
+
+	/* encrypt data authorization key */
+	for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
+		td->encauth[i] = td->xorhash[i] ^ blobauth[i];
+
+	/* calculate authorization HMAC value */
+	if (pcrinfosize == 0) {
+		/* no pcr info specified */
+		ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+				   sess.enonce, td->nonceodd, cont,
+				   sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+				   td->encauth, sizeof(uint32_t), &pcrsize,
+				   sizeof(uint32_t), &datsize, datalen, data, 0,
+				   0);
+	} else {
+		/* pcr info specified */
+		ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+				   sess.enonce, td->nonceodd, cont,
+				   sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+				   td->encauth, sizeof(uint32_t), &pcrsize,
+				   pcrinfosize, pcrinfo, sizeof(uint32_t),
+				   &datsize, datalen, data, 0, 0);
+	}
+	if (ret < 0)
+		goto out;
+
+	/* build and send the TPM request packet */
+	tpm_buf_reset(tb, TPM_TAG_RQU_AUTH1_COMMAND, TPM_ORD_SEAL);
+	tpm_buf_append_u32(tb, keyhandle);
+	tpm_buf_append(tb, td->encauth, SHA1_DIGEST_SIZE);
+	tpm_buf_append_u32(tb, pcrinfosize);
+	tpm_buf_append(tb, pcrinfo, pcrinfosize);
+	tpm_buf_append_u32(tb, datalen);
+	tpm_buf_append(tb, data, datalen);
+	tpm_buf_append_u32(tb, sess.handle);
+	tpm_buf_append(tb, td->nonceodd, TPM_NONCE_SIZE);
+	tpm_buf_append_u8(tb, cont);
+	tpm_buf_append(tb, td->pubauth, SHA1_DIGEST_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0)
+		goto out;
+
+	/* calculate the size of the returned Blob */
+	sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
+	encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
+			     sizeof(uint32_t) + sealinfosize);
+	storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
+	    sizeof(uint32_t) + encdatasize;
+
+	/* check the HMAC in the response */
+	ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
+			     SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
+			     0);
+
+	/* copy the returned blob to caller */
+	if (!ret) {
+		memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
+		*bloblen = storedsize;
+	}
+out:
+	kzfree(td);
+	return ret;
+}
+
+/*
+ * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
+ */
+static int tpm_unseal(struct tpm_buf *tb,
+		      uint32_t keyhandle, const unsigned char *keyauth,
+		      const unsigned char *blob, int bloblen,
+		      const unsigned char *blobauth,
+		      unsigned char *data, unsigned int *datalen)
+{
+	unsigned char nonceodd[TPM_NONCE_SIZE];
+	unsigned char enonce1[TPM_NONCE_SIZE];
+	unsigned char enonce2[TPM_NONCE_SIZE];
+	unsigned char authdata1[SHA1_DIGEST_SIZE];
+	unsigned char authdata2[SHA1_DIGEST_SIZE];
+	uint32_t authhandle1 = 0;
+	uint32_t authhandle2 = 0;
+	unsigned char cont = 0;
+	uint32_t ordinal;
+	uint32_t keyhndl;
+	int ret;
+
+	/* sessions for unsealing key and data */
+	ret = oiap(tb, &authhandle1, enonce1);
+	if (ret < 0) {
+		pr_info("trusted_key: oiap failed (%d)\n", ret);
+		return ret;
+	}
+	ret = oiap(tb, &authhandle2, enonce2);
+	if (ret < 0) {
+		pr_info("trusted_key: oiap failed (%d)\n", ret);
+		return ret;
+	}
+
+	ordinal = htonl(TPM_ORD_UNSEAL);
+	keyhndl = htonl(SRKHANDLE);
+	ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
+	if (ret != TPM_NONCE_SIZE) {
+		pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
+		return ret;
+	}
+	ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
+			   enonce1, nonceodd, cont, sizeof(uint32_t),
+			   &ordinal, bloblen, blob, 0, 0);
+	if (ret < 0)
+		return ret;
+	ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
+			   enonce2, nonceodd, cont, sizeof(uint32_t),
+			   &ordinal, bloblen, blob, 0, 0);
+	if (ret < 0)
+		return ret;
+
+	/* build and send TPM request packet */
+	tpm_buf_reset(tb, TPM_TAG_RQU_AUTH2_COMMAND, TPM_ORD_UNSEAL);
+	tpm_buf_append_u32(tb, keyhandle);
+	tpm_buf_append(tb, blob, bloblen);
+	tpm_buf_append_u32(tb, authhandle1);
+	tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
+	tpm_buf_append_u8(tb, cont);
+	tpm_buf_append(tb, authdata1, SHA1_DIGEST_SIZE);
+	tpm_buf_append_u32(tb, authhandle2);
+	tpm_buf_append(tb, nonceodd, TPM_NONCE_SIZE);
+	tpm_buf_append_u8(tb, cont);
+	tpm_buf_append(tb, authdata2, SHA1_DIGEST_SIZE);
+
+	ret = trusted_tpm_send(tb->data, MAX_BUF_SIZE);
+	if (ret < 0) {
+		pr_info("trusted_key: authhmac failed (%d)\n", ret);
+		return ret;
+	}
+
+	*datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
+	ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
+			     keyauth, SHA1_DIGEST_SIZE,
+			     blobauth, SHA1_DIGEST_SIZE,
+			     sizeof(uint32_t), TPM_DATA_OFFSET,
+			     *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
+			     0);
+	if (ret < 0) {
+		pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
+		return ret;
+	}
+	memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
+	return 0;
+}
+
+/*
+ * Have the TPM seal(encrypt) the symmetric key
+ */
+static int key_seal(struct trusted_key_payload *p,
+		    struct trusted_key_options *o)
+{
+	struct tpm_buf tb;
+	int ret;
+
+	ret = tpm_buf_init(&tb, 0, 0);
+	if (ret)
+		return ret;
+
+	/* include migratable flag at end of sealed key */
+	p->key[p->key_len] = p->migratable;
+
+	ret = tpm_seal(&tb, o->keytype, o->keyhandle, o->keyauth,
+		       p->key, p->key_len + 1, p->blob, &p->blob_len,
+		       o->blobauth, o->pcrinfo, o->pcrinfo_len);
+	if (ret < 0)
+		pr_info("trusted_key: srkseal failed (%d)\n", ret);
+
+	tpm_buf_destroy(&tb);
+	return ret;
+}
+
+/*
+ * Have the TPM unseal(decrypt) the symmetric key
+ */
+static int key_unseal(struct trusted_key_payload *p,
+		      struct trusted_key_options *o)
+{
+	struct tpm_buf tb;
+	int ret;
+
+	ret = tpm_buf_init(&tb, 0, 0);
+	if (ret)
+		return ret;
+
+	ret = tpm_unseal(&tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
+			 o->blobauth, p->key, &p->key_len);
+	if (ret < 0)
+		pr_info("trusted_key: srkunseal failed (%d)\n", ret);
+	else
+		/* pull migratable flag out of sealed key */
+		p->migratable = p->key[--p->key_len];
+
+	tpm_buf_destroy(&tb);
+	return ret;
+}
+
+enum {
+	Opt_err,
+	Opt_new, Opt_load, Opt_update,
+	Opt_keyhandle, Opt_keyauth, Opt_blobauth,
+	Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
+	Opt_hash,
+	Opt_policydigest,
+	Opt_policyhandle,
+};
+
+static const match_table_t key_tokens = {
+	{Opt_new, "new"},
+	{Opt_load, "load"},
+	{Opt_update, "update"},
+	{Opt_keyhandle, "keyhandle=%s"},
+	{Opt_keyauth, "keyauth=%s"},
+	{Opt_blobauth, "blobauth=%s"},
+	{Opt_pcrinfo, "pcrinfo=%s"},
+	{Opt_pcrlock, "pcrlock=%s"},
+	{Opt_migratable, "migratable=%s"},
+	{Opt_hash, "hash=%s"},
+	{Opt_policydigest, "policydigest=%s"},
+	{Opt_policyhandle, "policyhandle=%s"},
+	{Opt_err, NULL}
+};
+
+/* can have zero or more token= options */
+static int getoptions(char *c, struct trusted_key_payload *pay,
+		      struct trusted_key_options *opt)
+{
+	substring_t args[MAX_OPT_ARGS];
+	char *p = c;
+	int token;
+	int res;
+	unsigned long handle;
+	unsigned long lock;
+	unsigned long token_mask = 0;
+	unsigned int digest_len;
+	int i;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(chip);
+	if (tpm2 < 0)
+		return tpm2;
+
+	opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1;
+
+	while ((p = strsep(&c, " \t"))) {
+		if (*p == '\0' || *p == ' ' || *p == '\t')
+			continue;
+		token = match_token(p, key_tokens, args);
+		if (test_and_set_bit(token, &token_mask))
+			return -EINVAL;
+
+		switch (token) {
+		case Opt_pcrinfo:
+			opt->pcrinfo_len = strlen(args[0].from) / 2;
+			if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->pcrinfo, args[0].from,
+				      opt->pcrinfo_len);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_keyhandle:
+			res = kstrtoul(args[0].from, 16, &handle);
+			if (res < 0)
+				return -EINVAL;
+			opt->keytype = SEAL_keytype;
+			opt->keyhandle = handle;
+			break;
+		case Opt_keyauth:
+			if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->keyauth, args[0].from,
+				      SHA1_DIGEST_SIZE);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_blobauth:
+			if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+				return -EINVAL;
+			res = hex2bin(opt->blobauth, args[0].from,
+				      SHA1_DIGEST_SIZE);
+			if (res < 0)
+				return -EINVAL;
+			break;
+		case Opt_migratable:
+			if (*args[0].from == '0')
+				pay->migratable = 0;
+			else
+				return -EINVAL;
+			break;
+		case Opt_pcrlock:
+			res = kstrtoul(args[0].from, 10, &lock);
+			if (res < 0)
+				return -EINVAL;
+			opt->pcrlock = lock;
+			break;
+		case Opt_hash:
+			if (test_bit(Opt_policydigest, &token_mask))
+				return -EINVAL;
+			for (i = 0; i < HASH_ALGO__LAST; i++) {
+				if (!strcmp(args[0].from, hash_algo_name[i])) {
+					opt->hash = i;
+					break;
+				}
+			}
+			if (i == HASH_ALGO__LAST)
+				return -EINVAL;
+			if  (!tpm2 && i != HASH_ALGO_SHA1) {
+				pr_info("trusted_key: TPM 1.x only supports SHA-1.\n");
+				return -EINVAL;
+			}
+			break;
+		case Opt_policydigest:
+			digest_len = hash_digest_size[opt->hash];
+			if (!tpm2 || strlen(args[0].from) != (2 * digest_len))
+				return -EINVAL;
+			res = hex2bin(opt->policydigest, args[0].from,
+				      digest_len);
+			if (res < 0)
+				return -EINVAL;
+			opt->policydigest_len = digest_len;
+			break;
+		case Opt_policyhandle:
+			if (!tpm2)
+				return -EINVAL;
+			res = kstrtoul(args[0].from, 16, &handle);
+			if (res < 0)
+				return -EINVAL;
+			opt->policyhandle = handle;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return 0;
+}
+
+/*
+ * datablob_parse - parse the keyctl data and fill in the
+ * 		    payload and options structures
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, struct trusted_key_payload *p,
+			  struct trusted_key_options *o)
+{
+	substring_t args[MAX_OPT_ARGS];
+	long keylen;
+	int ret = -EINVAL;
+	int key_cmd;
+	char *c;
+
+	/* main command */
+	c = strsep(&datablob, " \t");
+	if (!c)
+		return -EINVAL;
+	key_cmd = match_token(c, key_tokens, args);
+	switch (key_cmd) {
+	case Opt_new:
+		/* first argument is key size */
+		c = strsep(&datablob, " \t");
+		if (!c)
+			return -EINVAL;
+		ret = kstrtol(c, 10, &keylen);
+		if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
+			return -EINVAL;
+		p->key_len = keylen;
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_new;
+		break;
+	case Opt_load:
+		/* first argument is sealed blob */
+		c = strsep(&datablob, " \t");
+		if (!c)
+			return -EINVAL;
+		p->blob_len = strlen(c) / 2;
+		if (p->blob_len > MAX_BLOB_SIZE)
+			return -EINVAL;
+		ret = hex2bin(p->blob, c, p->blob_len);
+		if (ret < 0)
+			return -EINVAL;
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_load;
+		break;
+	case Opt_update:
+		/* all arguments are options */
+		ret = getoptions(datablob, p, o);
+		if (ret < 0)
+			return ret;
+		ret = Opt_update;
+		break;
+	case Opt_err:
+		return -EINVAL;
+		break;
+	}
+	return ret;
+}
+
+static struct trusted_key_options *trusted_options_alloc(void)
+{
+	struct trusted_key_options *options;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(chip);
+	if (tpm2 < 0)
+		return NULL;
+
+	options = kzalloc(sizeof *options, GFP_KERNEL);
+	if (options) {
+		/* set any non-zero defaults */
+		options->keytype = SRK_keytype;
+
+		if (!tpm2)
+			options->keyhandle = SRKHANDLE;
+	}
+	return options;
+}
+
+static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
+{
+	struct trusted_key_payload *p = NULL;
+	int ret;
+
+	ret = key_payload_reserve(key, sizeof *p);
+	if (ret < 0)
+		return p;
+	p = kzalloc(sizeof *p, GFP_KERNEL);
+	if (p)
+		p->migratable = 1; /* migratable by default */
+	return p;
+}
+
+/*
+ * trusted_instantiate - create a new trusted key
+ *
+ * Unseal an existing trusted blob or, for a new key, get a
+ * random key, then seal and create a trusted key-type key,
+ * adding it to the specified keyring.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int trusted_instantiate(struct key *key,
+			       struct key_preparsed_payload *prep)
+{
+	struct trusted_key_payload *payload = NULL;
+	struct trusted_key_options *options = NULL;
+	size_t datalen = prep->datalen;
+	char *datablob;
+	int ret = 0;
+	int key_cmd;
+	size_t key_len;
+	int tpm2;
+
+	tpm2 = tpm_is_tpm2(chip);
+	if (tpm2 < 0)
+		return tpm2;
+
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	datablob = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!datablob)
+		return -ENOMEM;
+	memcpy(datablob, prep->data, datalen);
+	datablob[datalen] = '\0';
+
+	options = trusted_options_alloc();
+	if (!options) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	payload = trusted_payload_alloc(key);
+	if (!payload) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	key_cmd = datablob_parse(datablob, payload, options);
+	if (key_cmd < 0) {
+		ret = key_cmd;
+		goto out;
+	}
+
+	if (!options->keyhandle) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	dump_payload(payload);
+	dump_options(options);
+
+	switch (key_cmd) {
+	case Opt_load:
+		if (tpm2)
+			ret = tpm_unseal_trusted(chip, payload, options);
+		else
+			ret = key_unseal(payload, options);
+		dump_payload(payload);
+		dump_options(options);
+		if (ret < 0)
+			pr_info("trusted_key: key_unseal failed (%d)\n", ret);
+		break;
+	case Opt_new:
+		key_len = payload->key_len;
+		ret = tpm_get_random(chip, payload->key, key_len);
+		if (ret != key_len) {
+			pr_info("trusted_key: key_create failed (%d)\n", ret);
+			goto out;
+		}
+		if (tpm2)
+			ret = tpm_seal_trusted(chip, payload, options);
+		else
+			ret = key_seal(payload, options);
+		if (ret < 0)
+			pr_info("trusted_key: key_seal failed (%d)\n", ret);
+		break;
+	default:
+		ret = -EINVAL;
+		goto out;
+	}
+	if (!ret && options->pcrlock)
+		ret = pcrlock(options->pcrlock);
+out:
+	kzfree(datablob);
+	kzfree(options);
+	if (!ret)
+		rcu_assign_keypointer(key, payload);
+	else
+		kzfree(payload);
+	return ret;
+}
+
+static void trusted_rcu_free(struct rcu_head *rcu)
+{
+	struct trusted_key_payload *p;
+
+	p = container_of(rcu, struct trusted_key_payload, rcu);
+	kzfree(p);
+}
+
+/*
+ * trusted_update - reseal an existing key with new PCR values
+ */
+static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
+{
+	struct trusted_key_payload *p;
+	struct trusted_key_payload *new_p;
+	struct trusted_key_options *new_o;
+	size_t datalen = prep->datalen;
+	char *datablob;
+	int ret = 0;
+
+	if (key_is_negative(key))
+		return -ENOKEY;
+	p = key->payload.data[0];
+	if (!p->migratable)
+		return -EPERM;
+	if (datalen <= 0 || datalen > 32767 || !prep->data)
+		return -EINVAL;
+
+	datablob = kmalloc(datalen + 1, GFP_KERNEL);
+	if (!datablob)
+		return -ENOMEM;
+	new_o = trusted_options_alloc();
+	if (!new_o) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	new_p = trusted_payload_alloc(key);
+	if (!new_p) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	memcpy(datablob, prep->data, datalen);
+	datablob[datalen] = '\0';
+	ret = datablob_parse(datablob, new_p, new_o);
+	if (ret != Opt_update) {
+		ret = -EINVAL;
+		kzfree(new_p);
+		goto out;
+	}
+
+	if (!new_o->keyhandle) {
+		ret = -EINVAL;
+		kzfree(new_p);
+		goto out;
+	}
+
+	/* copy old key values, and reseal with new pcrs */
+	new_p->migratable = p->migratable;
+	new_p->key_len = p->key_len;
+	memcpy(new_p->key, p->key, p->key_len);
+	dump_payload(p);
+	dump_payload(new_p);
+
+	ret = key_seal(new_p, new_o);
+	if (ret < 0) {
+		pr_info("trusted_key: key_seal failed (%d)\n", ret);
+		kzfree(new_p);
+		goto out;
+	}
+	if (new_o->pcrlock) {
+		ret = pcrlock(new_o->pcrlock);
+		if (ret < 0) {
+			pr_info("trusted_key: pcrlock failed (%d)\n", ret);
+			kzfree(new_p);
+			goto out;
+		}
+	}
+	rcu_assign_keypointer(key, new_p);
+	call_rcu(&p->rcu, trusted_rcu_free);
+out:
+	kzfree(datablob);
+	kzfree(new_o);
+	return ret;
+}
+
+/*
+ * trusted_read - copy the sealed blob data to userspace in hex.
+ * On success, return to userspace the trusted key datablob size.
+ */
+static long trusted_read(const struct key *key, char __user *buffer,
+			 size_t buflen)
+{
+	const struct trusted_key_payload *p;
+	char *ascii_buf;
+	char *bufp;
+	int i;
+
+	p = dereference_key_locked(key);
+	if (!p)
+		return -EINVAL;
+
+	if (buffer && buflen >= 2 * p->blob_len) {
+		ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
+		if (!ascii_buf)
+			return -ENOMEM;
+
+		bufp = ascii_buf;
+		for (i = 0; i < p->blob_len; i++)
+			bufp = hex_byte_pack(bufp, p->blob[i]);
+		if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
+			kzfree(ascii_buf);
+			return -EFAULT;
+		}
+		kzfree(ascii_buf);
+	}
+	return 2 * p->blob_len;
+}
+
+/*
+ * trusted_destroy - clear and free the key's payload
+ */
+static void trusted_destroy(struct key *key)
+{
+	kzfree(key->payload.data[0]);
+}
+
+struct key_type key_type_trusted = {
+	.name = "trusted",
+	.instantiate = trusted_instantiate,
+	.update = trusted_update,
+	.destroy = trusted_destroy,
+	.describe = user_describe,
+	.read = trusted_read,
+};
+
+EXPORT_SYMBOL_GPL(key_type_trusted);
+
+static void trusted_shash_release(void)
+{
+	if (hashalg)
+		crypto_free_shash(hashalg);
+	if (hmacalg)
+		crypto_free_shash(hmacalg);
+}
+
+static int __init trusted_shash_alloc(void)
+{
+	int ret;
+
+	hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
+	if (IS_ERR(hmacalg)) {
+		pr_info("trusted_key: could not allocate crypto %s\n",
+			hmac_alg);
+		return PTR_ERR(hmacalg);
+	}
+
+	hashalg = crypto_alloc_shash(hash_alg, 0, 0);
+	if (IS_ERR(hashalg)) {
+		pr_info("trusted_key: could not allocate crypto %s\n",
+			hash_alg);
+		ret = PTR_ERR(hashalg);
+		goto hashalg_fail;
+	}
+
+	return 0;
+
+hashalg_fail:
+	crypto_free_shash(hmacalg);
+	return ret;
+}
+
+static int __init init_digests(void)
+{
+	int i;
+
+	digests = kcalloc(chip->nr_allocated_banks, sizeof(*digests),
+			  GFP_KERNEL);
+	if (!digests)
+		return -ENOMEM;
+
+	for (i = 0; i < chip->nr_allocated_banks; i++)
+		digests[i].alg_id = chip->allocated_banks[i].alg_id;
+
+	return 0;
+}
+
+static int __init init_trusted(void)
+{
+	int ret;
+
+	/* encrypted_keys.ko depends on successful load of this module even if
+	 * TPM is not used.
+	 */
+	chip = tpm_default_chip();
+	if (!chip)
+		return 0;
+
+	ret = init_digests();
+	if (ret < 0)
+		goto err_put;
+	ret = trusted_shash_alloc();
+	if (ret < 0)
+		goto err_free;
+	ret = register_key_type(&key_type_trusted);
+	if (ret < 0)
+		goto err_release;
+	return 0;
+err_release:
+	trusted_shash_release();
+err_free:
+	kfree(digests);
+err_put:
+	put_device(&chip->dev);
+	return ret;
+}
+
+static void __exit cleanup_trusted(void)
+{
+	if (chip) {
+		put_device(&chip->dev);
+		kfree(digests);
+		trusted_shash_release();
+		unregister_key_type(&key_type_trusted);
+	}
+}
+
+late_initcall(init_trusted);
+module_exit(cleanup_trusted);
+
+MODULE_LICENSE("GPL");