Re: [PATCH v8 1/4] KEYS: trusted: Add generic trusted keys framework

Jarkko Sakkinen
2020-11-24T03:42:41Z

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On Tue, Nov 03, 2020 at 09:31:43PM +0530, Sumit Garg 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 trusted keys
> support in case platform doesn't posses a TPM device.
>
> Add a generic trusted keys framework where underlying implementations
> can be easily plugged in. Create struct trusted_key_ops to achieve this,
> which contains necessary functions of a backend.
>
> Also, define a module parameter in order to select a particular trust
> source in case a platform support multiple trust sources. In case its
> not specified then implementation itetrates through trust sources list
> starting with TPM and assign the first trust source as a backend which
> has initiazed successfully during iteration.
>
> Note that current implementation only supports a single trust source at
> runtime which is either selectable at compile time or during boot via
> aforementioned module parameter.
>
> Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
> ---
> Documentation/admin-guide/kernel-parameters.txt | 12 +
> include/keys/trusted-type.h | 47 ++++

> include/keys/trusted_tpm.h | 17 +-
> security/keys/trusted-keys/Makefile | 1 +
> security/keys/trusted-keys/trusted_core.c | 350 ++++++++++++++++++++++++
> security/keys/trusted-keys/trusted_tpm1.c | 336 ++++-------------------
> 6 files changed, 468 insertions(+), 295 deletions(-)
> create mode 100644 security/keys/trusted-keys/trusted_core.c
>
> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index 526d65d..df9b9fe 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -5392,6 +5392,18 @@
> See Documentation/admin-guide/mm/transhuge.rst
> for more details.
>
> + trusted.source= [KEYS]
> + Format: <string>
> + This parameter identifies the trust source as a backend
> + for trusted keys implementation. Supported trust
> + sources:
> + - "tpm"
> + - "tee"
> + If not specified then it defaults to iterating through
> + the trust source list starting with TPM and assigns the
> + first trust source as a backend which is initialized
> + successfully during iteration.
> +
> tsc= Disable clocksource stability checks for TSC.
> Format: <string>
> [x86] reliable: mark tsc clocksource as reliable, this
> diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h
> index a94c03a..a566451 100644
> --- a/include/keys/trusted-type.h
> +++ b/include/keys/trusted-type.h
> @@ -40,6 +40,53 @@ 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;
> +
> + /* Initialize key interface. */
> + int (*init)(void);
> +
> + /* Seal a key. */
> + int (*seal)(struct trusted_key_payload *p, char *datablob);
> +
> + /* Unseal a key. */
> + int (*unseal)(struct trusted_key_payload *p, char *datablob);
> +
> + /* Get a randomized key. */
> + int (*get_random)(unsigned char *key, size_t key_len);
> +
> + /* Exit key interface. */
> + void (*exit)(void);
> +};
> +
> +struct trusted_key_source {
> + char *name;
> + struct trusted_key_ops *ops;
> +};
> +
> extern struct key_type key_type_trusted;
>
> +#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 a56d8e1..fb3280a 100644
> --- a/include/keys/trusted_tpm.h
> +++ b/include/keys/trusted_tpm.h
> @@ -16,6 +16,8 @@
> #define LOAD32N(buffer, offset) (*(uint32_t *)&buffer[offset])
> #define LOAD16(buffer, offset) (ntohs(*(uint16_t *)&buffer[offset]))
>
> +extern struct trusted_key_ops tpm_trusted_key_ops;
> +
> struct osapsess {
> uint32_t handle;
> unsigned char secret[SHA1_DIGEST_SIZE];
> @@ -60,17 +62,6 @@ 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,
> @@ -96,10 +87,6 @@ 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 7b73ceb..49e3bcf 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_core.o
> trusted-y += trusted_tpm1.o
> trusted-y += trusted_tpm2.o
> diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c
> new file mode 100644
> index 0000000..aa4f2a0
> --- /dev/null
> +++ b/security/keys/trusted-keys/trusted_core.c
> @@ -0,0 +1,350 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2010 IBM Corporation
> + * Copyright (c) 2019-2020, Linaro Limited
> + *
> + * See Documentation/security/keys/trusted-encrypted.rst
> + */
> +
> +#include <keys/user-type.h>
> +#include <keys/trusted-type.h>
> +#include <keys/trusted_tpm.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/static_call.h>
> +#include <linux/string.h>
> +#include <linux/uaccess.h>
> +
> +static char *trusted_key_source;
> +module_param_named(source, trusted_key_source, charp, 0);
> +MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)");
> +
> +static const struct trusted_key_source trusted_key_sources[] = {
> +#if defined(CONFIG_TCG_TPM)
> + { "tpm", &tpm_trusted_key_ops },
> +#endif
> +};
> +
> +DEFINE_STATIC_CALL_NULL(trusted_key_init, *trusted_key_sources[0].ops->init);
> +DEFINE_STATIC_CALL_NULL(trusted_key_seal, *trusted_key_sources[0].ops->seal);
> +DEFINE_STATIC_CALL_NULL(trusted_key_unseal,
> + *trusted_key_sources[0].ops->unseal);
> +DEFINE_STATIC_CALL_NULL(trusted_key_get_random,
> + *trusted_key_sources[0].ops->get_random);
> +DEFINE_STATIC_CALL_NULL(trusted_key_exit, *trusted_key_sources[0].ops->exit);
> +static unsigned char migratable;
> +
> +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 = 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 = static_call(trusted_key_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 = static_call(trusted_key_get_random)(payload->key,
> + key_len);
> + if (ret != key_len) {
> + pr_info("trusted_key: key_create failed (%d)\n", ret);
> + goto out;
> + }
> +
> + ret = static_call(trusted_key_seal)(payload, datablob);
> + if (ret < 0)
> + pr_info("trusted_key: key_seal failed (%d)\n", ret);
> + break;
> + default:
> + ret = -EINVAL;
> + }
> +out:
> + kfree_sensitive(datablob);
> + if (!ret)
> + rcu_assign_keypointer(key, payload);
> + else
> + kfree_sensitive(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);
> + kfree_sensitive(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;
> + kfree_sensitive(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 = static_call(trusted_key_seal)(new_p, datablob);
> + if (ret < 0) {
> + pr_info("trusted_key: key_seal failed (%d)\n", ret);
> + kfree_sensitive(new_p);
> + goto out;
> + }
> +
> + rcu_assign_keypointer(key, new_p);
> + call_rcu(&p->rcu, trusted_rcu_free);
> +out:
> + kfree_sensitive(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 *buffer,
> + size_t buflen)
> +{
> + const struct trusted_key_payload *p;
> + char *bufp;
> + int i;
> +
> + p = dereference_key_locked(key);
> + if (!p)
> + return -EINVAL;
> +
> + if (buffer && buflen >= 2 * p->blob_len) {
> + bufp = buffer;
> + for (i = 0; i < p->blob_len; i++)
> + bufp = hex_byte_pack(bufp, p->blob[i]);
> + }
> + return 2 * p->blob_len;
> +}
> +
> +/*
> + * trusted_destroy - clear and free the key's payload
> + */
> +static void trusted_destroy(struct key *key)
> +{
> + kfree_sensitive(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 < ARRAY_SIZE(trusted_key_sources); i++) {
> + if (trusted_key_source &&
> + strncmp(trusted_key_source, trusted_key_sources[i].name,
> + strlen(trusted_key_sources[i].name)))
> + continue;
> +
> + static_call_update(trusted_key_init,
> + trusted_key_sources[i].ops->init);
> + static_call_update(trusted_key_seal,
> + trusted_key_sources[i].ops->seal);
> + static_call_update(trusted_key_unseal,
> + trusted_key_sources[i].ops->unseal);
> + static_call_update(trusted_key_get_random,
> + trusted_key_sources[i].ops->get_random);
> + static_call_update(trusted_key_exit,
> + trusted_key_sources[i].ops->exit);
> + migratable = trusted_key_sources[i].ops->migratable;
> +
> + ret = static_call(trusted_key_init)();
> + if (!ret)
> + 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)
> +{
> + static_call(trusted_key_exit)();
> +}
> +
> +late_initcall(init_trusted);
> +module_exit(cleanup_trusted);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/security/keys/trusted-keys/trusted_tpm1.c b/security/keys/trusted-keys/trusted_tpm1.c
> index b9fe02e..bd03914 100644
> --- a/security/keys/trusted-keys/trusted_tpm1.c
> +++ b/security/keys/trusted-keys/trusted_tpm1.c
> @@ -1,29 +1,22 @@
> // SPDX-License-Identifier: GPL-2.0-only
> /*
> * Copyright (C) 2010 IBM Corporation
> - *
> - * Author:
> - * David Safford <safford@us.ibm.com>
> + * Copyright (c) 2019-2020, Linaro Limited
> *
> * 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>
>
> @@ -703,7 +696,6 @@ 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,
> @@ -712,9 +704,6 @@ 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"},
> @@ -841,71 +830,6 @@ 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;
> @@ -926,248 +850,99 @@ static struct trusted_key_options *trusted_options_alloc(void)
> return options;
> }
>
> -static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
> +static int trusted_tpm_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 = tpm2_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 = tpm2_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 = tpm2_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:
> - kfree_sensitive(datablob);
> kfree_sensitive(options);
> - if (!ret)
> - rcu_assign_keypointer(key, payload);
> - else
> - kfree_sensitive(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);
> - kfree_sensitive(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 trusted_tpm_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;
> - kfree_sensitive(new_p);
> + ret = getoptions(datablob, p, options);
> + if (ret < 0)
> goto out;
> - }
> + dump_options(options);
>
> - if (!new_o->keyhandle) {
> + if (!options->keyhandle) {
> ret = -EINVAL;
> - kfree_sensitive(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 = tpm2_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);
> - kfree_sensitive(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);
> - kfree_sensitive(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:
> - kfree_sensitive(datablob);
> - kfree_sensitive(new_o);
> + kfree_sensitive(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 *buffer,
> - size_t buflen)
> -{
> - const struct trusted_key_payload *p;
> - char *bufp;
> - int i;
> -
> - p = dereference_key_locked(key);
> - if (!p)
> - return -EINVAL;
> -
> - if (buffer && buflen >= 2 * p->blob_len) {
> - bufp = buffer;
> - for (i = 0; i < p->blob_len; i++)
> - bufp = hex_byte_pack(bufp, p->blob[i]);
> - }
> - return 2 * p->blob_len;
> -}
> -
> -/*
> - * trusted_destroy - clear and free the key's payload
> - */
> -static void trusted_destroy(struct key *key)
> +static int trusted_tpm_get_random(unsigned char *key, size_t key_len)
> {
> - kfree_sensitive(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)
> @@ -1182,14 +957,14 @@ 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",

Let's just add interal trusted.h file with:

#undef pr_fmt
#define pr_fmt(fmt) "trusted_key: " fmt

and remove tags from these. Does not add value to have separate tags
for backends. Makes the klog only a bit messier I think.

> hash_alg);
> ret = PTR_ERR(hashalg);
> goto hashalg_fail;
> @@ -1217,16 +992,13 @@ static int __init init_digests(void)
> return 0;
> }
>
> -static int __init init_trusted(void)
> +static int trusted_tpm_init(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)
> @@ -1247,7 +1019,7 @@ static int __init init_trusted(void)
> return ret;
> }
>
> -static void __exit cleanup_trusted(void)
> +static void trusted_tpm_exit(void)
> {
> if (chip) {
> put_device(&chip->dev);
> @@ -1257,7 +1029,11 @@ 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 = trusted_tpm_init,
> + .seal = trusted_tpm_seal,
> + .unseal = trusted_tpm_unseal,
> + .get_random = trusted_tpm_get_random,
> + .exit = trusted_tpm_exit,
> +};
> --
> 2.7.4
>
>

/Jarkko