[PATCH v8 1/4] KEYS: trusted: Add generic trusted keys framework
Sumit Garg
sumit.garg at linaro.org
Mon Feb 15 13:13:39 UTC 2021
On Tue, 24 Nov 2020 at 09:12, Jarkko Sakkinen <jarkko at kernel.org> wrote:
>
> 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 at linux.intel.com>
> > Signed-off-by: Sumit Garg <sumit.garg at 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 at 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.
>
Okay makes sense, will do this in the next version.
-Sumit
>
> > 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
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