| Message ID | 1591107505-6030-2-git-send-email-sumit.garg@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce TEE based Trusted Keys support | expand |
On Tue, Jun 02, 2020 at 07:48:22PM +0530, Sumit Garg wrote: > diff --git a/security/keys/Kconfig b/security/keys/Kconfig > index 47c0415..22632c6 100644 > --- a/security/keys/Kconfig > +++ b/security/keys/Kconfig > @@ -72,17 +72,26 @@ config BIG_KEYS > > config TRUSTED_KEYS > tristate "TRUSTED KEYS" > - depends on KEYS && TCG_TPM > + depends on KEYS > + help > + This option provides support for creating, sealing, and unsealing > + keys in the kernel. Trusted keys are random number symmetric keys, > + generated and sealed by a trust source (TPM or TEE). Userspace will > + only ever see encrypted blobs. > + > + If you are unsure as to whether this is required, answer N. > + > +config TRUSTED_TPM TRUSTED_TPM_KEYS > + bool "TPM based TRUSTED KEYS" > + depends on TRUSTED_KEYS && TCG_TPM > select CRYPTO > select CRYPTO_HMAC > select CRYPTO_SHA1 > select CRYPTO_HASH_INFO > help > - This option provides support for creating, sealing, and unsealing > - keys in the kernel. Trusted keys are random number symmetric keys, > - generated and RSA-sealed by the TPM. The TPM only unseals the keys, > - if the boot PCRs and other criteria match. Userspace will only ever > - see encrypted blobs. > + This option provides support for TPM based trusted keys where TPM acts > + as the trust source. The keys are RSA-sealed by the TPM and it only > + unseals the keys, if the boot PCRs and other criteria match. > > If you are unsure as to whether this is required, answer N. > > diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile > index 7b73ceb..03c3ad4 100644 > --- a/security/keys/trusted-keys/Makefile > +++ b/security/keys/trusted-keys/Makefile > @@ -4,5 +4,6 @@ > # > > obj-$(CONFIG_TRUSTED_KEYS) += trusted.o > -trusted-y += trusted_tpm1.o > -trusted-y += trusted_tpm2.o > +trusted-y += trusted_core.o > +trusted-$(CONFIG_TRUSTED_TPM) += trusted_tpm1.o > +trusted-$(CONFIG_TRUSTED_TPM) += 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..3d07d27 > --- /dev/null > +++ b/security/keys/trusted-keys/trusted_core.c > @@ -0,0 +1,319 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2010 IBM Corporation > + * Copyright (c) 2019, Linaro Limited > + * > + * Author: > + * David Safford <safford@us.ibm.com> > + * Added generic trusted key framework: Sumit Garg <sumit.garg@linaro.org> Rather remove David's because 1. Git log gives a verifiable and exact log of authority. 2. David's commit was done post-epoch of Git. > + * > + * 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> > + > +#if defined(CONFIG_TRUSTED_TPM) > +static struct trusted_key_ops *trusted_key_ops = &tpm_trusted_key_ops; > +#else > +static struct trusted_key_ops *trusted_key_ops; > +#endif You should just have extern trusted_key_ops *trusted_key_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 = trusted_key_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 = trusted_key_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 = trusted_key_ops->get_random(payload->key, key_len); > + if (ret != key_len) { > + pr_info("trusted_key: key_create failed (%d)\n", ret); > + goto out; > + } > + > + ret = trusted_key_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 = trusted_key_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 *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) > +{ > + 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 ret; > + > + /* > + * encrypted_keys.ko depends on successful load of this module even if > + * trusted key implementation is not found. > + */ > + if (!trusted_key_ops) > + return 0; > + > + ret = trusted_key_ops->init(); > + if (ret == -ENODEV) > + return 0; > + > + return ret; > +} > + > +static void __exit cleanup_trusted(void) > +{ > + trusted_key_ops->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 8001ab0..e378b27 100644 > --- a/security/keys/trusted-keys/trusted_tpm1.c > +++ b/security/keys/trusted-keys/trusted_tpm1.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@us.ibm.com> > + * Switch to generic trusted key framework: Sumit Garg <sumit.garg@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> > > @@ -703,7 +700,6 @@ 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 +708,6 @@ 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 +834,6 @@ 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 +854,99 @@ 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_trusted_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: > - 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) > +static int tpm_trusted_unseal(struct trusted_key_payload *p, char *datablob) > { > - 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; > - 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 = 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); > - 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 *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) > +int tpm_trusted_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) > @@ -1182,14 +961,14 @@ 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; > @@ -1217,16 +996,13 @@ 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) > @@ -1247,7 +1023,7 @@ static int __init init_trusted(void) > return ret; > } > > -static void __exit cleanup_trusted(void) > +static void __exit exit_tpm_trusted(void) > { > if (chip) { > put_device(&chip->dev); > @@ -1257,7 +1033,12 @@ 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_trusted_seal, > + .unseal = tpm_trusted_unseal, > + .get_random = tpm_trusted_get_random, > + .exit = exit_tpm_trusted, > +}; > +EXPORT_SYMBOL_GPL(tpm_trusted_key_ops); > -- Rename this as trusted_key_ops and remove EXPORT_SYMBOL_GPL() > 2.7.4 > /Jarkko
+ Luke Hi Jarkko, Prior to addressing your comments below which seems to show your preference for compile time selection of trust source (TPM or TEE), I would just like to hear the reasons for this preference especially if it makes distro vendor's life difficult [1] to make opinionated selection which could rather be achieved dynamically based on platform capability. [1] https://lkml.org/lkml/2020/6/3/405 -Sumit On Mon, 15 Jun 2020 at 23:55, Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> wrote: > > On Tue, Jun 02, 2020 at 07:48:22PM +0530, Sumit Garg wrote: > > diff --git a/security/keys/Kconfig b/security/keys/Kconfig > > index 47c0415..22632c6 100644 > > --- a/security/keys/Kconfig > > +++ b/security/keys/Kconfig > > @@ -72,17 +72,26 @@ config BIG_KEYS > > > > config TRUSTED_KEYS > > tristate "TRUSTED KEYS" > > - depends on KEYS && TCG_TPM > > + depends on KEYS > > + help > > + This option provides support for creating, sealing, and unsealing > > + keys in the kernel. Trusted keys are random number symmetric keys, > > + generated and sealed by a trust source (TPM or TEE). Userspace will > > + only ever see encrypted blobs. > > + > > + If you are unsure as to whether this is required, answer N. > > + > > +config TRUSTED_TPM > > TRUSTED_TPM_KEYS > > > + bool "TPM based TRUSTED KEYS" > > + depends on TRUSTED_KEYS && TCG_TPM > > select CRYPTO > > select CRYPTO_HMAC > > select CRYPTO_SHA1 > > select CRYPTO_HASH_INFO > > help > > - This option provides support for creating, sealing, and unsealing > > - keys in the kernel. Trusted keys are random number symmetric keys, > > - generated and RSA-sealed by the TPM. The TPM only unseals the keys, > > - if the boot PCRs and other criteria match. Userspace will only ever > > - see encrypted blobs. > > + This option provides support for TPM based trusted keys where TPM acts > > + as the trust source. The keys are RSA-sealed by the TPM and it only > > + unseals the keys, if the boot PCRs and other criteria match. > > > > If you are unsure as to whether this is required, answer N. > > > > diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile > > index 7b73ceb..03c3ad4 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_tpm1.o > > -trusted-y += trusted_tpm2.o > > +trusted-y += trusted_core.o > > +trusted-$(CONFIG_TRUSTED_TPM) += trusted_tpm1.o > > +trusted-$(CONFIG_TRUSTED_TPM) += 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..3d07d27 > > --- /dev/null > > +++ b/security/keys/trusted-keys/trusted_core.c > > @@ -0,0 +1,319 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * Copyright (C) 2010 IBM Corporation > > + * Copyright (c) 2019, Linaro Limited > > + * > > + * Author: > > + * David Safford <safford@us.ibm.com> > > + * Added generic trusted key framework: Sumit Garg <sumit.garg@linaro.org> > > Rather remove David's because > > 1. Git log gives a verifiable and exact log of authority. > 2. David's commit was done post-epoch of Git. > > > + * > > + * 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> > > + > > +#if defined(CONFIG_TRUSTED_TPM) > > +static struct trusted_key_ops *trusted_key_ops = &tpm_trusted_key_ops; > > +#else > > +static struct trusted_key_ops *trusted_key_ops; > > +#endif > > You should just have > > extern trusted_key_ops *trusted_key_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 = trusted_key_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 = trusted_key_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 = trusted_key_ops->get_random(payload->key, key_len); > > + if (ret != key_len) { > > + pr_info("trusted_key: key_create failed (%d)\n", ret); > > + goto out; > > + } > > + > > + ret = trusted_key_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 = trusted_key_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 *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) > > +{ > > + 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 ret; > > + > > + /* > > + * encrypted_keys.ko depends on successful load of this module even if > > + * trusted key implementation is not found. > > + */ > > + if (!trusted_key_ops) > > + return 0; > > + > > + ret = trusted_key_ops->init(); > > + if (ret == -ENODEV) > > + return 0; > > + > > + return ret; > > +} > > + > > +static void __exit cleanup_trusted(void) > > +{ > > + trusted_key_ops->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 8001ab0..e378b27 100644 > > --- a/security/keys/trusted-keys/trusted_tpm1.c > > +++ b/security/keys/trusted-keys/trusted_tpm1.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@us.ibm.com> > > + * Switch to generic trusted key framework: Sumit Garg <sumit.garg@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> > > > > @@ -703,7 +700,6 @@ 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 +708,6 @@ 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 +834,6 @@ 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 +854,99 @@ 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_trusted_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: > > - 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) > > +static int tpm_trusted_unseal(struct trusted_key_payload *p, char *datablob) > > { > > - 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; > > - 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 = 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); > > - 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 *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) > > +int tpm_trusted_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) > > @@ -1182,14 +961,14 @@ 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; > > @@ -1217,16 +996,13 @@ 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) > > @@ -1247,7 +1023,7 @@ static int __init init_trusted(void) > > return ret; > > } > > > > -static void __exit cleanup_trusted(void) > > +static void __exit exit_tpm_trusted(void) > > { > > if (chip) { > > put_device(&chip->dev); > > @@ -1257,7 +1033,12 @@ 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_trusted_seal, > > + .unseal = tpm_trusted_unseal, > > + .get_random = tpm_trusted_get_random, > > + .exit = exit_tpm_trusted, > > +}; > > +EXPORT_SYMBOL_GPL(tpm_trusted_key_ops); > -- > > Rename this as trusted_key_ops and remove EXPORT_SYMBOL_GPL() > > > 2.7.4 > > > > /Jarkko
On Tue, Jun 16, 2020 at 07:02:37PM +0530, Sumit Garg wrote: > + Luke > > Hi Jarkko, > > Prior to addressing your comments below which seems to show your > preference for compile time selection of trust source (TPM or TEE), I > would just like to hear the reasons for this preference especially if > it makes distro vendor's life difficult [1] to make opinionated > selection which could rather be achieved dynamically based on platform > capability. > > [1] https://lkml.org/lkml/2020/6/3/405 > > -Sumit Hmm... I do get the distribution kernel point. OK, lets revert to dynamic then. Thanks for the remark. /Jarkko
On Thu, 18 Jun 2020 at 04:44, Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> wrote: > > On Tue, Jun 16, 2020 at 07:02:37PM +0530, Sumit Garg wrote: > > + Luke > > > > Hi Jarkko, > > > > Prior to addressing your comments below which seems to show your > > preference for compile time selection of trust source (TPM or TEE), I > > would just like to hear the reasons for this preference especially if > > it makes distro vendor's life difficult [1] to make opinionated > > selection which could rather be achieved dynamically based on platform > > capability. > > > > [1] https://lkml.org/lkml/2020/6/3/405 > > > > -Sumit > > Hmm... I do get the distribution kernel point. OK, lets revert to > dynamic then. Thanks for the remark. > > /Jarkko Thanks, will revert to dynamic mode in v6. -Sumit
On Thu, Jun 18, 2020 at 12:12:41PM +0530, Sumit Garg wrote: > On Thu, 18 Jun 2020 at 04:44, Jarkko Sakkinen > <jarkko.sakkinen@linux.intel.com> wrote: > > > > On Tue, Jun 16, 2020 at 07:02:37PM +0530, Sumit Garg wrote: > > > + Luke > > > > > > Hi Jarkko, > > > > > > Prior to addressing your comments below which seems to show your > > > preference for compile time selection of trust source (TPM or TEE), I > > > would just like to hear the reasons for this preference especially if > > > it makes distro vendor's life difficult [1] to make opinionated > > > selection which could rather be achieved dynamically based on platform > > > capability. > > > > > > [1] https://lkml.org/lkml/2020/6/3/405 > > > > > > -Sumit > > > > Hmm... I do get the distribution kernel point. OK, lets revert to > > dynamic then. Thanks for the remark. > > > > /Jarkko > > Thanks, will revert to dynamic mode in v6. Sorry about the extra trouble caused by me. /Jarkko
diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h index a94c03a..819a102 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; + + /* 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); +}; + extern struct key_type key_type_trusted; +#if defined(CONFIG_TRUSTED_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 a56d8e1..5753231 100644 --- a/include/keys/trusted_tpm.h +++ b/include/keys/trusted_tpm.h @@ -60,17 +60,6 @@ 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 +85,6 @@ 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/Kconfig b/security/keys/Kconfig index 47c0415..22632c6 100644 --- a/security/keys/Kconfig +++ b/security/keys/Kconfig @@ -72,17 +72,26 @@ config BIG_KEYS config TRUSTED_KEYS tristate "TRUSTED KEYS" - depends on KEYS && TCG_TPM + depends on KEYS + help + This option provides support for creating, sealing, and unsealing + keys in the kernel. Trusted keys are random number symmetric keys, + generated and sealed by a trust source (TPM or TEE). Userspace will + only ever see encrypted blobs. + + If you are unsure as to whether this is required, answer N. + +config TRUSTED_TPM + bool "TPM based TRUSTED KEYS" + depends on TRUSTED_KEYS && TCG_TPM select CRYPTO select CRYPTO_HMAC select CRYPTO_SHA1 select CRYPTO_HASH_INFO help - This option provides support for creating, sealing, and unsealing - keys in the kernel. Trusted keys are random number symmetric keys, - generated and RSA-sealed by the TPM. The TPM only unseals the keys, - if the boot PCRs and other criteria match. Userspace will only ever - see encrypted blobs. + This option provides support for TPM based trusted keys where TPM acts + as the trust source. The keys are RSA-sealed by the TPM and it only + unseals the keys, if the boot PCRs and other criteria match. If you are unsure as to whether this is required, answer N. diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile index 7b73ceb..03c3ad4 100644 --- a/security/keys/trusted-keys/Makefile +++ b/security/keys/trusted-keys/Makefile @@ -4,5 +4,6 @@ # obj-$(CONFIG_TRUSTED_KEYS) += trusted.o -trusted-y += trusted_tpm1.o -trusted-y += trusted_tpm2.o +trusted-y += trusted_core.o +trusted-$(CONFIG_TRUSTED_TPM) += trusted_tpm1.o +trusted-$(CONFIG_TRUSTED_TPM) += 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..3d07d27 --- /dev/null +++ b/security/keys/trusted-keys/trusted_core.c @@ -0,0 +1,319 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2010 IBM Corporation + * Copyright (c) 2019, Linaro Limited + * + * Author: + * David Safford <safford@us.ibm.com> + * Added generic trusted key framework: Sumit Garg <sumit.garg@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> + +#if defined(CONFIG_TRUSTED_TPM) +static struct trusted_key_ops *trusted_key_ops = &tpm_trusted_key_ops; +#else +static struct trusted_key_ops *trusted_key_ops; +#endif + +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 = trusted_key_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 = trusted_key_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 = trusted_key_ops->get_random(payload->key, key_len); + if (ret != key_len) { + pr_info("trusted_key: key_create failed (%d)\n", ret); + goto out; + } + + ret = trusted_key_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 = trusted_key_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 *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) +{ + 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 ret; + + /* + * encrypted_keys.ko depends on successful load of this module even if + * trusted key implementation is not found. + */ + if (!trusted_key_ops) + return 0; + + ret = trusted_key_ops->init(); + if (ret == -ENODEV) + return 0; + + return ret; +} + +static void __exit cleanup_trusted(void) +{ + trusted_key_ops->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 8001ab0..e378b27 100644 --- a/security/keys/trusted-keys/trusted_tpm1.c +++ b/security/keys/trusted-keys/trusted_tpm1.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@us.ibm.com> + * Switch to generic trusted key framework: Sumit Garg <sumit.garg@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> @@ -703,7 +700,6 @@ 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 +708,6 @@ 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 +834,6 @@ 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 +854,99 @@ 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_trusted_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: - 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) +static int tpm_trusted_unseal(struct trusted_key_payload *p, char *datablob) { - 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; - 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 = 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); - 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 *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) +int tpm_trusted_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) @@ -1182,14 +961,14 @@ 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; @@ -1217,16 +996,13 @@ 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) @@ -1247,7 +1023,7 @@ static int __init init_trusted(void) return ret; } -static void __exit cleanup_trusted(void) +static void __exit exit_tpm_trusted(void) { if (chip) { put_device(&chip->dev); @@ -1257,7 +1033,12 @@ 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_trusted_seal, + .unseal = tpm_trusted_unseal, + .get_random = tpm_trusted_get_random, + .exit = exit_tpm_trusted, +}; +EXPORT_SYMBOL_GPL(tpm_trusted_key_ops);
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. So this patch tries to add generic trusted keys framework where underlying implementations like TPM, TEE etc. could be easily plugged-in. Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Signed-off-by: Sumit Garg <sumit.garg@linaro.org> --- include/keys/trusted-type.h | 45 ++++ include/keys/trusted_tpm.h | 15 -- security/keys/Kconfig | 21 +- security/keys/trusted-keys/Makefile | 5 +- security/keys/trusted-keys/trusted_core.c | 319 ++++++++++++++++++++++++++++ security/keys/trusted-keys/trusted_tpm1.c | 335 ++++++------------------------ 6 files changed, 440 insertions(+), 300 deletions(-) create mode 100644 security/keys/trusted-keys/trusted_core.c