Merge branch 'master'; commit 'v2.6.38-rc7' into next

1 files changed, 1181 insertions, 0 deletions

diff --git a/security/keys/trusted.c b/security/keys/trusted.c
new file mode 100644
index 000000000000..83fc92e297cd
--- /dev/null
+++ b/security/keys/trusted.c
@@ -0,0 +1,1181 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Author:
+ * David Safford <safford@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/keys-trusted-encrypted.txt
+ */
+
+#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 "trusted.h"
+
+static const char hmac_alg[] = "hmac(sha1)";
+static const char hash_alg[] = "sha1";
+
+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;
+        sdesc->shash.flags = 0x0;
+        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);
+        kfree(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:
+        kfree(sdesc);
+        return ret;
+}
+
+/*
+ * calculate authorization info fields to send to TPM
+ */
+static int TSS_authhmac(unsigned char *digest, const unsigned char *key,
+                        unsigned int keylen, unsigned char *h1,
+                        unsigned char *h2, unsigned char h3, ...)
+{
+        unsigned char paramdigest[SHA1_DIGEST_SIZE];
+        struct sdesc *sdesc;
+        unsigned int dlen;
+        unsigned char *data;
+        unsigned char c;
+        int ret;
+        va_list argp;
+
+        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:
+        kfree(sdesc);
+        return ret;
+}
+
+/*
+ * verify the AUTH1_COMMAND (Seal) result from TPM
+ */
+static 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;
+
+        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:
+        kfree(sdesc);
+        return ret;
+}
+
+/*
+ * 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:
+        kfree(sdesc);
+        return ret;
+}
+
+/*
+ * For key specific tpm requests, we will generate and send our
+ * own TPM command packets using the drivers send function.
+ */
+static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd,
+                            size_t buflen)
+{
+        int rc;
+
+        dump_tpm_buf(cmd);
+        rc = tpm_send(chip_num, cmd, buflen);
+        dump_tpm_buf(cmd);
+        if (rc > 0)
+                /* Can't return positive return codes values to keyctl */
+                rc = -EPERM;
+        return rc;
+}
+
+/*
+ * get a random value from TPM
+ */
+static int tpm_get_random(struct tpm_buf *tb, unsigned char *buf, uint32_t len)
+{
+        int ret;
+
+        INIT_BUF(tb);
+        store16(tb, TPM_TAG_RQU_COMMAND);
+        store32(tb, TPM_GETRANDOM_SIZE);
+        store32(tb, TPM_ORD_GETRANDOM);
+        store32(tb, len);
+        ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, sizeof tb->data);
+        if (!ret)
+                memcpy(buf, tb->data + TPM_GETRANDOM_SIZE, len);
+        return ret;
+}
+
+static int my_get_random(unsigned char *buf, int len)
+{
+        struct tpm_buf *tb;
+        int ret;
+
+        tb = kmalloc(sizeof *tb, GFP_KERNEL);
+        if (!tb)
+                return -ENOMEM;
+        ret = tpm_get_random(tb, buf, len);
+
+        kfree(tb);
+        return ret;
+}
+
+/*
+ * 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)
+{
+        unsigned char hash[SHA1_DIGEST_SIZE];
+        int ret;
+
+        if (!capable(CAP_SYS_ADMIN))
+                return -EPERM;
+        ret = my_get_random(hash, SHA1_DIGEST_SIZE);
+        if (ret < 0)
+                return ret;
+        return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -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(tb, ononce, TPM_NONCE_SIZE);
+        if (ret < 0)
+                return ret;
+
+        INIT_BUF(tb);
+        store16(tb, TPM_TAG_RQU_COMMAND);
+        store32(tb, TPM_OSAP_SIZE);
+        store32(tb, TPM_ORD_OSAP);
+        store16(tb, type);
+        store32(tb, handle);
+        storebytes(tb, ononce, TPM_NONCE_SIZE);
+
+        ret = trusted_tpm_send(TPM_ANY_NUM, 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
+ */
+static int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
+{
+        int ret;
+
+        INIT_BUF(tb);
+        store16(tb, TPM_TAG_RQU_COMMAND);
+        store32(tb, TPM_OIAP_SIZE);
+        store32(tb, TPM_ORD_OIAP);
+        ret = trusted_tpm_send(TPM_ANY_NUM, 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;
+}
+
+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(tb, td->nonceodd, TPM_NONCE_SIZE);
+        if (ret < 0)
+                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 */
+        INIT_BUF(tb);
+        store16(tb, TPM_TAG_RQU_AUTH1_COMMAND);
+        store32(tb, TPM_SEAL_SIZE + pcrinfosize + datalen);
+        store32(tb, TPM_ORD_SEAL);
+        store32(tb, keyhandle);
+        storebytes(tb, td->encauth, SHA1_DIGEST_SIZE);
+        store32(tb, pcrinfosize);
+        storebytes(tb, pcrinfo, pcrinfosize);
+        store32(tb, datalen);
+        storebytes(tb, data, datalen);
+        store32(tb, sess.handle);
+        storebytes(tb, td->nonceodd, TPM_NONCE_SIZE);
+        store8(tb, cont);
+        storebytes(tb, td->pubauth, SHA1_DIGEST_SIZE);
+
+        ret = trusted_tpm_send(TPM_ANY_NUM, 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(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(tb, nonceodd, TPM_NONCE_SIZE);
+        if (ret < 0) {
+                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 */
+        INIT_BUF(tb);
+        store16(tb, TPM_TAG_RQU_AUTH2_COMMAND);
+        store32(tb, TPM_UNSEAL_SIZE + bloblen);
+        store32(tb, TPM_ORD_UNSEAL);
+        store32(tb, keyhandle);
+        storebytes(tb, blob, bloblen);
+        store32(tb, authhandle1);
+        storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+        store8(tb, cont);
+        storebytes(tb, authdata1, SHA1_DIGEST_SIZE);
+        store32(tb, authhandle2);
+        storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+        store8(tb, cont);
+        storebytes(tb, authdata2, SHA1_DIGEST_SIZE);
+
+        ret = trusted_tpm_send(TPM_ANY_NUM, 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;
+
+        tb = kzalloc(sizeof *tb, GFP_KERNEL);
+        if (!tb)
+                return -ENOMEM;
+
+        /* 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);
+
+        kfree(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;
+
+        tb = kzalloc(sizeof *tb, GFP_KERNEL);
+        if (!tb)
+                return -ENOMEM;
+
+        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];
+
+        kfree(tb);
+        return ret;
+}
+
+enum {
+        Opt_err = -1,
+        Opt_new, Opt_load, Opt_update,
+        Opt_keyhandle, Opt_keyauth, Opt_blobauth,
+        Opt_pcrinfo, Opt_pcrlock, Opt_migratable
+};
+
+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_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;
+
+        while ((p = strsep(&c, " \t"))) {
+                if (*p == '\0' || *p == ' ' || *p == '\t')
+                        continue;
+                token = match_token(p, key_tokens, args);
+
+                switch (token) {
+                case Opt_pcrinfo:
+                        opt->pcrinfo_len = strlen(args[0].from) / 2;
+                        if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
+                                return -EINVAL;
+                        hex2bin(opt->pcrinfo, args[0].from, opt->pcrinfo_len);
+                        break;
+                case Opt_keyhandle:
+                        res = strict_strtoul(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;
+                        hex2bin(opt->keyauth, args[0].from, SHA1_DIGEST_SIZE);
+                        break;
+                case Opt_blobauth:
+                        if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+                                return -EINVAL;
+                        hex2bin(opt->blobauth, args[0].from, SHA1_DIGEST_SIZE);
+                        break;
+                case Opt_migratable:
+                        if (*args[0].from == '0')
+                                pay->migratable = 0;
+                        else
+                                return -EINVAL;
+                        break;
+                case Opt_pcrlock:
+                        res = strict_strtoul(args[0].from, 10, &lock);
+                        if (res < 0)
+                                return -EINVAL;
+                        opt->pcrlock = lock;
+                        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 = strict_strtol(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;
+                hex2bin(p->blob, c, p->blob_len);
+                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;
+
+        options = kzalloc(sizeof *options, GFP_KERNEL);
+        if (options) {
+                /* set any non-zero defaults */
+                options->keytype = SRK_keytype;
+                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, const void *data,
+                               size_t datalen)
+{
+        struct trusted_key_payload *payload = NULL;
+        struct trusted_key_options *options = NULL;
+        char *datablob;
+        int ret = 0;
+        int key_cmd;
+
+        if (datalen <= 0 || datalen > 32767 || !data)
+                return -EINVAL;
+
+        datablob = kmalloc(datalen + 1, GFP_KERNEL);
+        if (!datablob)
+                return -ENOMEM;
+        memcpy(datablob, 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;
+        }
+
+        dump_payload(payload);
+        dump_options(options);
+
+        switch (key_cmd) {
+        case Opt_load:
+                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:
+                ret = my_get_random(payload->key, payload->key_len);
+                if (ret < 0) {
+                        pr_info("trusted_key: key_create failed (%d)\n", ret);
+                        goto out;
+                }
+                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:
+        kfree(datablob);
+        kfree(options);
+        if (!ret)
+                rcu_assign_pointer(key->payload.data, payload);
+        else
+                kfree(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);
+        memset(p->key, 0, p->key_len);
+        kfree(p);
+}
+
+/*
+ * trusted_update - reseal an existing key with new PCR values
+ */
+static int trusted_update(struct key *key, const void *data, size_t datalen)
+{
+        struct trusted_key_payload *p = key->payload.data;
+        struct trusted_key_payload *new_p;
+        struct trusted_key_options *new_o;
+        char *datablob;
+        int ret = 0;
+
+        if (!p->migratable)
+                return -EPERM;
+        if (datalen <= 0 || datalen > 32767 || !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, data, datalen);
+        datablob[datalen] = '\0';
+        ret = datablob_parse(datablob, new_p, new_o);
+        if (ret != Opt_update) {
+                ret = -EINVAL;
+                kfree(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);
+                kfree(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);
+                        kfree(new_p);
+                        goto out;
+                }
+        }
+        rcu_assign_pointer(key->payload.data, new_p);
+        call_rcu(&p->rcu, trusted_rcu_free);
+out:
+        kfree(datablob);
+        kfree(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)
+{
+        struct trusted_key_payload *p;
+        char *ascii_buf;
+        char *bufp;
+        int i;
+
+        p = rcu_dereference_protected(key->payload.data,
+                        rwsem_is_locked(&((struct key *)key)->sem));
+        if (!p)
+                return -EINVAL;
+        if (!buffer || buflen <= 0)
+                return 2 * p->blob_len;
+        ascii_buf = kmalloc(2 * p->blob_len, GFP_KERNEL);
+        if (!ascii_buf)
+                return -ENOMEM;
+
+        bufp = ascii_buf;
+        for (i = 0; i < p->blob_len; i++)
+                bufp = pack_hex_byte(bufp, p->blob[i]);
+        if ((copy_to_user(buffer, ascii_buf, 2 * p->blob_len)) != 0) {
+                kfree(ascii_buf);
+                return -EFAULT;
+        }
+        kfree(ascii_buf);
+        return 2 * p->blob_len;
+}
+
+/*
+ * trusted_destroy - before freeing the key, clear the decrypted data
+ */
+static void trusted_destroy(struct key *key)
+{
+        struct trusted_key_payload *p = key->payload.data;
+
+        if (!p)
+                return;
+        memset(p->key, 0, p->key_len);
+        kfree(key->payload.data);
+}
+
+struct key_type key_type_trusted = {
+        .name = "trusted",
+        .instantiate = trusted_instantiate,
+        .update = trusted_update,
+        .match = user_match,
+        .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, CRYPTO_ALG_ASYNC);
+        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, CRYPTO_ALG_ASYNC);
+        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_trusted(void)
+{
+        int ret;
+
+        ret = trusted_shash_alloc();
+        if (ret < 0)
+                return ret;
+        ret = register_key_type(&key_type_trusted);
+        if (ret < 0)
+                trusted_shash_release();
+        return ret;
+}
+
+static void __exit cleanup_trusted(void)
+{
+        trusted_shash_release();
+        unregister_key_type(&key_type_trusted);
+}
+
+late_initcall(init_trusted);
+module_exit(cleanup_trusted);
+
+MODULE_LICENSE("GPL");