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-rw-r--r--security/keys/trusted-keys/trusted_tpm1.c1074
1 files changed, 1074 insertions, 0 deletions
diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
new file mode 100644
index 000000000..aa108bea6
--- /dev/null
+++ b/security/keys/trusted-keys/trusted_tpm1.c
@@ -0,0 +1,1074 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2010 IBM Corporation
+ * Copyright (c) 2019-2021, Linaro Limited
+ *
+ * See Documentation/security/keys/trusted-encrypted.rst
+ */
+
+#include <crypto/hash_info.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/trusted-type.h>
+#include <linux/key-type.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/sha1.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("can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
+ kfree_sensitive(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("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:
+ kfree_sensitive(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("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:
+ kfree_sensitive(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("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:
+ kfree_sensitive(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("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:
+ kfree_sensitive(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 < 0)
+ return ret;
+
+ if (ret != TPM_NONCE_SIZE)
+ return -EIO;
+
+ 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 < 0)
+ goto out;
+
+ if (ret != TPM_NONCE_SIZE) {
+ ret = -EIO;
+ 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:
+ kfree_sensitive(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;
+ int ret;
+
+ /* sessions for unsealing key and data */
+ ret = oiap(tb, &authhandle1, enonce1);
+ if (ret < 0) {
+ pr_info("oiap failed (%d)\n", ret);
+ return ret;
+ }
+ ret = oiap(tb, &authhandle2, enonce2);
+ if (ret < 0) {
+ pr_info("oiap failed (%d)\n", ret);
+ return ret;
+ }
+
+ ordinal = htonl(TPM_ORD_UNSEAL);
+ ret = tpm_get_random(chip, nonceodd, TPM_NONCE_SIZE);
+ if (ret < 0)
+ return ret;
+
+ if (ret != TPM_NONCE_SIZE) {
+ pr_info("tpm_get_random failed (%d)\n", ret);
+ return -EIO;
+ }
+ 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("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("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("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("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_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_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;
+
+ if (!c)
+ return 0;
+
+ 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:
+ /*
+ * TPM 1.2 authorizations are sha1 hashes passed in as
+ * hex strings. TPM 2.0 authorizations are simple
+ * passwords (although it can take a hash as well)
+ */
+ opt->blobauth_len = strlen(args[0].from);
+
+ if (opt->blobauth_len == 2 * TPM_DIGEST_SIZE) {
+ res = hex2bin(opt->blobauth, args[0].from,
+ TPM_DIGEST_SIZE);
+ if (res < 0)
+ return -EINVAL;
+
+ opt->blobauth_len = TPM_DIGEST_SIZE;
+ break;
+ }
+
+ if (tpm2 && opt->blobauth_len <= sizeof(opt->blobauth)) {
+ memcpy(opt->blobauth, args[0].from,
+ opt->blobauth_len);
+ break;
+ }
+
+ return -EINVAL;
+
+ break;
+
+ case Opt_migratable:
+ if (*args[0].from == '0')
+ pay->migratable = 0;
+ else if (*args[0].from != '1')
+ 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("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;
+}
+
+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 int trusted_tpm_seal(struct trusted_key_payload *p, char *datablob)
+{
+ struct trusted_key_options *options = NULL;
+ int ret = 0;
+ int tpm2;
+
+ tpm2 = tpm_is_tpm2(chip);
+ if (tpm2 < 0)
+ return tpm2;
+
+ options = trusted_options_alloc();
+ if (!options)
+ return -ENOMEM;
+
+ ret = getoptions(datablob, p, options);
+ if (ret < 0)
+ goto out;
+ dump_options(options);
+
+ if (!options->keyhandle && !tpm2) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (tpm2)
+ ret = tpm2_seal_trusted(chip, p, options);
+ else
+ ret = key_seal(p, options);
+ if (ret < 0) {
+ pr_info("key_seal failed (%d)\n", ret);
+ goto out;
+ }
+
+ if (options->pcrlock) {
+ ret = pcrlock(options->pcrlock);
+ if (ret < 0) {
+ pr_info("pcrlock failed (%d)\n", ret);
+ goto out;
+ }
+ }
+out:
+ kfree_sensitive(options);
+ return ret;
+}
+
+static int trusted_tpm_unseal(struct trusted_key_payload *p, char *datablob)
+{
+ struct trusted_key_options *options = NULL;
+ int ret = 0;
+ int tpm2;
+
+ tpm2 = tpm_is_tpm2(chip);
+ if (tpm2 < 0)
+ return tpm2;
+
+ options = trusted_options_alloc();
+ if (!options)
+ return -ENOMEM;
+
+ ret = getoptions(datablob, p, options);
+ if (ret < 0)
+ goto out;
+ dump_options(options);
+
+ if (!options->keyhandle && !tpm2) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (tpm2)
+ ret = tpm2_unseal_trusted(chip, p, options);
+ else
+ ret = key_unseal(p, options);
+ if (ret < 0)
+ pr_info("key_unseal failed (%d)\n", ret);
+
+ if (options->pcrlock) {
+ ret = pcrlock(options->pcrlock);
+ if (ret < 0) {
+ pr_info("pcrlock failed (%d)\n", ret);
+ goto out;
+ }
+ }
+out:
+ kfree_sensitive(options);
+ return ret;
+}
+
+static int trusted_tpm_get_random(unsigned char *key, size_t key_len)
+{
+ return tpm_get_random(chip, key, key_len);
+}
+
+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("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("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 trusted_tpm_init(void)
+{
+ int ret;
+
+ chip = tpm_default_chip();
+ if (!chip)
+ return -ENODEV;
+
+ 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 trusted_tpm_exit(void)
+{
+ if (chip) {
+ put_device(&chip->dev);
+ kfree(digests);
+ trusted_shash_release();
+ unregister_key_type(&key_type_trusted);
+ }
+}
+
+struct trusted_key_ops trusted_key_tpm_ops = {
+ .migratable = 1, /* migratable by default */
+ .init = trusted_tpm_init,
+ .seal = trusted_tpm_seal,
+ .unseal = trusted_tpm_unseal,
+ .get_random = trusted_tpm_get_random,
+ .exit = trusted_tpm_exit,
+};