[RFC/RFT v4 5/5] KEYS: trusted: Add generic trusted keys framework

Sumit Garg sumit.garg at linaro.org
Fri Aug 30 09:19:31 UTC 2019


On Tue, 13 Aug 2019 at 13:24, Sumit Garg <sumit.garg at linaro.org> wrote:
>
> Current trusted keys framework is tightly coupled to use TPM device as
> an underlying implementation which makes it difficult for implementations
> like Trusted Execution Environment (TEE) etc. to provide trusked keys
> support in case platform doesn't posses a TPM device.
>
> So this patch tries to add generic trusted keys framework where underlying
> implemtations like TPM, TEE etc. could be easily plugged-in.
>
> Suggested-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
> Signed-off-by: Sumit Garg <sumit.garg at linaro.org>
> ---
>  include/keys/trusted-type.h                 |  45 ++++
>  include/keys/trusted_tpm.h                  |  15 --
>  security/keys/trusted-keys/Makefile         |   1 +
>  security/keys/trusted-keys/trusted-common.c | 343 +++++++++++++++++++++++++++
>  security/keys/trusted-keys/trusted-tpm.c    | 345 +++++-----------------------
>  5 files changed, 447 insertions(+), 302 deletions(-)
>  create mode 100644 security/keys/trusted-keys/trusted-common.c
>

Any comments/feedback on this patch before I send next version of TEE
patch-set with this patch included?

-Sumit

> diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h
> index a94c03a..5559010 100644
> --- a/include/keys/trusted-type.h
> +++ b/include/keys/trusted-type.h
> @@ -40,6 +40,51 @@ struct trusted_key_options {
>         uint32_t policyhandle;
>  };
>
> +struct trusted_key_ops {
> +       /*
> +        * flag to indicate if trusted key implementation supports migration
> +        * or not.
> +        */
> +       unsigned char migratable;
> +
> +       /* trusted key init */
> +       int (*init)(void);
> +
> +       /* seal a trusted key */
> +       int (*seal)(struct trusted_key_payload *p, char *datablob);
> +
> +       /* unseal a trusted key */
> +       int (*unseal)(struct trusted_key_payload *p, char *datablob);
> +
> +       /* get random trusted key */
> +       int (*get_random)(unsigned char *key, size_t key_len);
> +
> +       /* trusted key cleanup */
> +       void (*cleanup)(void);
> +};
> +
>  extern struct key_type key_type_trusted;
> +#if defined(CONFIG_TCG_TPM)
> +extern struct trusted_key_ops tpm_trusted_key_ops;
> +#endif
> +
> +#define TRUSTED_DEBUG 0
> +
> +#if TRUSTED_DEBUG
> +static inline void dump_payload(struct trusted_key_payload *p)
> +{
> +       pr_info("trusted_key: key_len %d\n", p->key_len);
> +       print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
> +                      16, 1, p->key, p->key_len, 0);
> +       pr_info("trusted_key: bloblen %d\n", p->blob_len);
> +       print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
> +                      16, 1, p->blob, p->blob_len, 0);
> +       pr_info("trusted_key: migratable %d\n", p->migratable);
> +}
> +#else
> +static inline void dump_payload(struct trusted_key_payload *p)
> +{
> +}
> +#endif
>
>  #endif /* _KEYS_TRUSTED_TYPE_H */
> diff --git a/include/keys/trusted_tpm.h b/include/keys/trusted_tpm.h
> index 0d72106..7b59344 100644
> --- a/include/keys/trusted_tpm.h
> +++ b/include/keys/trusted_tpm.h
> @@ -57,17 +57,6 @@ static inline void dump_options(struct trusted_key_options *o)
>                        16, 1, o->pcrinfo, o->pcrinfo_len, 0);
>  }
>
> -static inline void dump_payload(struct trusted_key_payload *p)
> -{
> -       pr_info("trusted_key: key_len %d\n", p->key_len);
> -       print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
> -                      16, 1, p->key, p->key_len, 0);
> -       pr_info("trusted_key: bloblen %d\n", p->blob_len);
> -       print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
> -                      16, 1, p->blob, p->blob_len, 0);
> -       pr_info("trusted_key: migratable %d\n", p->migratable);
> -}
> -
>  static inline void dump_sess(struct osapsess *s)
>  {
>         print_hex_dump(KERN_INFO, "trusted-key: handle ", DUMP_PREFIX_NONE,
> @@ -93,10 +82,6 @@ static inline void dump_options(struct trusted_key_options *o)
>  {
>  }
>
> -static inline void dump_payload(struct trusted_key_payload *p)
> -{
> -}
> -
>  static inline void dump_sess(struct osapsess *s)
>  {
>  }
> diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile
> index fb42e94..9a4f721 100644
> --- a/security/keys/trusted-keys/Makefile
> +++ b/security/keys/trusted-keys/Makefile
> @@ -4,5 +4,6 @@
>  #
>
>  obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
> +trusted-y += trusted-common.o
>  trusted-y += trusted-tpm.o
>  trusted-y += trusted-tpm2.o
> diff --git a/security/keys/trusted-keys/trusted-common.c b/security/keys/trusted-keys/trusted-common.c
> new file mode 100644
> index 0000000..8f00fde
> --- /dev/null
> +++ b/security/keys/trusted-keys/trusted-common.c
> @@ -0,0 +1,343 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2010 IBM Corporation
> + * Copyright (c) 2019, Linaro Limited
> + *
> + * Author:
> + * David Safford <safford at us.ibm.com>
> + * Added generic trusted key framework: Sumit Garg <sumit.garg at linaro.org>
> + *
> + * See Documentation/security/keys/trusted-encrypted.rst
> + */
> +
> +#include <keys/user-type.h>
> +#include <keys/trusted-type.h>
> +#include <linux/capability.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/key-type.h>
> +#include <linux/module.h>
> +#include <linux/parser.h>
> +#include <linux/rcupdate.h>
> +#include <linux/slab.h>
> +#include <linux/string.h>
> +#include <linux/uaccess.h>
> +
> +static struct trusted_key_ops *available_tk_ops[] = {
> +#if defined(CONFIG_TCG_TPM)
> +       &tpm_trusted_key_ops,
> +#endif
> +};
> +static struct trusted_key_ops *tk_ops;
> +
> +enum {
> +       Opt_err,
> +       Opt_new, Opt_load, Opt_update,
> +};
> +
> +static const match_table_t key_tokens = {
> +       {Opt_new, "new"},
> +       {Opt_load, "load"},
> +       {Opt_update, "update"},
> +       {Opt_err, NULL}
> +};
> +
> +/*
> + * datablob_parse - parse the keyctl data and fill in the
> + *                  payload structure
> + *
> + * On success returns 0, otherwise -EINVAL.
> + */
> +static int datablob_parse(char *datablob, struct trusted_key_payload *p)
> +{
> +       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 = 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 = Opt_load;
> +               break;
> +       case Opt_update:
> +               ret = Opt_update;
> +               break;
> +       case Opt_err:
> +               return -EINVAL;
> +       }
> +       return ret;
> +}
> +
> +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);
> +
> +       p->migratable = tk_ops->migratable;
> +
> +       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;
> +       size_t datalen = prep->datalen;
> +       char *datablob;
> +       int ret = 0;
> +       int key_cmd;
> +       size_t key_len;
> +
> +       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';
> +
> +       payload = trusted_payload_alloc(key);
> +       if (!payload) {
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       key_cmd = datablob_parse(datablob, payload);
> +       if (key_cmd < 0) {
> +               ret = key_cmd;
> +               goto out;
> +       }
> +
> +       dump_payload(payload);
> +
> +       switch (key_cmd) {
> +       case Opt_load:
> +               ret = tk_ops->unseal(payload, datablob);
> +               dump_payload(payload);
> +               if (ret < 0)
> +                       pr_info("trusted_key: key_unseal failed (%d)\n", ret);
> +               break;
> +       case Opt_new:
> +               key_len = payload->key_len;
> +               ret = tk_ops->get_random(payload->key, key_len);
> +               if (ret != key_len) {
> +                       pr_info("trusted_key: key_create failed (%d)\n", ret);
> +                       goto out;
> +               }
> +
> +               ret = tk_ops->seal(payload, datablob);
> +               if (ret < 0)
> +                       pr_info("trusted_key: key_seal failed (%d)\n", ret);
> +               break;
> +       default:
> +               ret = -EINVAL;
> +       }
> +out:
> +       kzfree(datablob);
> +       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;
> +       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_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);
> +       if (ret != Opt_update) {
> +               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 = tk_ops->seal(new_p, datablob);
> +       if (ret < 0) {
> +               pr_info("trusted_key: key_seal 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);
> +       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 int __init init_trusted(void)
> +{
> +       int i, ret = 0;
> +
> +       for (i = 0; i < sizeof(available_tk_ops); i++) {
> +               tk_ops = available_tk_ops[i];
> +
> +               if (!(tk_ops && tk_ops->init && tk_ops->seal &&
> +                     tk_ops->unseal && tk_ops->get_random))
> +                       continue;
> +
> +               ret = tk_ops->init();
> +               if (ret) {
> +                       if (tk_ops->cleanup)
> +                               tk_ops->cleanup();
> +               } else {
> +                       break;
> +               }
> +       }
> +
> +       /*
> +        * encrypted_keys.ko depends on successful load of this module even if
> +        * trusted key implementation is not found.
> +        */
> +       if (ret == -ENODEV)
> +               return 0;
> +
> +       return ret;
> +}
> +
> +static void __exit cleanup_trusted(void)
> +{
> +       if (tk_ops->cleanup)
> +               tk_ops->cleanup();
> +}
> +
> +late_initcall(init_trusted);
> +module_exit(cleanup_trusted);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/security/keys/trusted-keys/trusted-tpm.c b/security/keys/trusted-keys/trusted-tpm.c
> index 66687e7..dab7c32 100644
> --- a/security/keys/trusted-keys/trusted-tpm.c
> +++ b/security/keys/trusted-keys/trusted-tpm.c
> @@ -1,29 +1,26 @@
>  // SPDX-License-Identifier: GPL-2.0-only
>  /*
>   * Copyright (C) 2010 IBM Corporation
> + * Copyright (c) 2019, Linaro Limited
>   *
>   * Author:
>   * David Safford <safford at us.ibm.com>
> + * Switch to generic trusted key framework: Sumit Garg <sumit.garg at linaro.org>
>   *
>   * 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>
>
> @@ -705,7 +702,6 @@ static int key_unseal(struct trusted_key_payload *p,
>
>  enum {
>         Opt_err,
> -       Opt_new, Opt_load, Opt_update,
>         Opt_keyhandle, Opt_keyauth, Opt_blobauth,
>         Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
>         Opt_hash,
> @@ -714,9 +710,6 @@ enum {
>  };
>
>  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"},
> @@ -843,71 +836,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay,
>         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;
> @@ -928,258 +856,99 @@ static struct trusted_key_options *trusted_options_alloc(void)
>         return options;
>  }
>
> -static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
> +static int tpm_tk_seal(struct trusted_key_payload *p, char *datablob)
>  {
> -       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;
> -       }
> +       if (!options)
> +               return -ENOMEM;
>
> -       key_cmd = datablob_parse(datablob, payload, options);
> -       if (key_cmd < 0) {
> -               ret = key_cmd;
> +       ret = getoptions(datablob, p, options);
> +       if (ret < 0)
>                 goto out;
> -       }
> +       dump_options(options);
>
>         if (!options->keyhandle) {
>                 ret = -EINVAL;
>                 goto out;
>         }
>
> -       dump_payload(payload);
> -       dump_options(options);
> +       if (tpm2)
> +               ret = tpm_seal_trusted(chip, p, options);
> +       else
> +               ret = key_seal(p, options);
> +       if (ret < 0) {
> +               pr_info("tpm_trusted_key: key_seal failed (%d)\n", ret);
> +               goto out;
> +       }
>
> -       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);
> +       if (options->pcrlock) {
> +               ret = pcrlock(options->pcrlock);
> +               if (ret < 0) {
> +                       pr_info("tpm_trusted_key: pcrlock 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)
> +static int tpm_tk_unseal(struct trusted_key_payload *p, char *datablob)
>  {
> -       struct trusted_key_payload *p;
> -       struct trusted_key_payload *new_p;
> -       struct trusted_key_options *new_o;
> -       size_t datalen = prep->datalen;
> -       char *datablob;
> +       struct trusted_key_options *options = NULL;
>         int ret = 0;
> +       int tpm2;
>
> -       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;
> +       tpm2 = tpm_is_tpm2(chip);
> +       if (tpm2 < 0)
> +               return tpm2;
>
> -       datablob = kmalloc(datalen + 1, GFP_KERNEL);
> -       if (!datablob)
> +       options = trusted_options_alloc();
> +       if (!options)
>                 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);
> +       ret = getoptions(datablob, p, options);
> +       if (ret < 0)
>                 goto out;
> -       }
> +       dump_options(options);
>
> -       if (!new_o->keyhandle) {
> +       if (!options->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);
> +       if (tpm2)
> +               ret = tpm_unseal_trusted(chip, p, options);
> +       else
> +               ret = key_unseal(p, options);
> +       if (ret < 0)
> +               pr_info("tpm_trusted_key: key_unseal failed (%d)\n", ret);
>
> -       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 (options->pcrlock) {
> +               ret = pcrlock(options->pcrlock);
>                 if (ret < 0) {
> -                       pr_info("trusted_key: pcrlock failed (%d)\n", ret);
> -                       kzfree(new_p);
> +                       pr_info("tpm_trusted_key: pcrlock failed (%d)\n", ret);
>                         goto out;
>                 }
>         }
> -       rcu_assign_keypointer(key, new_p);
> -       call_rcu(&p->rcu, trusted_rcu_free);
>  out:
> -       kzfree(datablob);
> -       kzfree(new_o);
> +       kzfree(options);
>         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)
> +int tpm_tk_get_random(unsigned char *key, size_t key_len)
>  {
> -       kzfree(key->payload.data[0]);
> +       return tpm_get_random(chip, key, key_len);
>  }
>
> -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)
> @@ -1194,14 +963,14 @@ static int __init trusted_shash_alloc(void)
>
>         hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
>         if (IS_ERR(hmacalg)) {
> -               pr_info("trusted_key: could not allocate crypto %s\n",
> +               pr_info("tpm_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",
> +               pr_info("tpm_trusted_key: could not allocate crypto %s\n",
>                         hash_alg);
>                 ret = PTR_ERR(hashalg);
>                 goto hashalg_fail;
> @@ -1237,16 +1006,13 @@ static int __init init_digests(void)
>         return 0;
>  }
>
> -static int __init init_trusted(void)
> +static int __init init_tpm_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;
> +               return -ENODEV;
>
>         ret = init_digests();
>         if (ret < 0)
> @@ -1267,7 +1033,7 @@ static int __init init_trusted(void)
>         return ret;
>  }
>
> -static void __exit cleanup_trusted(void)
> +static void __exit cleanup_tpm_trusted(void)
>  {
>         if (chip) {
>                 put_device(&chip->dev);
> @@ -1277,7 +1043,12 @@ static void __exit cleanup_trusted(void)
>         }
>  }
>
> -late_initcall(init_trusted);
> -module_exit(cleanup_trusted);
> -
> -MODULE_LICENSE("GPL");
> +struct trusted_key_ops tpm_trusted_key_ops = {
> +       .migratable = 1, /* migratable by default */
> +       .init = init_tpm_trusted,
> +       .seal = tpm_tk_seal,
> +       .unseal = tpm_tk_unseal,
> +       .get_random = tpm_tk_get_random,
> +       .cleanup = cleanup_tpm_trusted,
> +};
> +EXPORT_SYMBOL_GPL(tpm_trusted_key_ops);
> --
> 2.7.4
>



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