From 903be6bb84c544551150a6f5aab9fda1ed9a6895 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Tue, 9 Oct 2018 17:48:02 +0100 Subject: KEYS: asym_tpm: add skeleton for asym_tpm [ver #2] This patch adds the basic skeleton for the asym_tpm asymmetric key subtype. Signed-off-by: Denis Kenzior Signed-off-by: David Howells Tested-by: Marcel Holtmann Reviewed-by: Marcel Holtmann Signed-off-by: James Morris --- crypto/asymmetric_keys/Kconfig | 11 +++++ crypto/asymmetric_keys/Makefile | 1 + crypto/asymmetric_keys/asym_tpm.c | 90 +++++++++++++++++++++++++++++++++++++++ include/crypto/asym_tpm_subtype.h | 16 +++++++ 4 files changed, 118 insertions(+) create mode 100644 crypto/asymmetric_keys/asym_tpm.c create mode 100644 include/crypto/asym_tpm_subtype.h diff --git a/crypto/asymmetric_keys/Kconfig b/crypto/asymmetric_keys/Kconfig index 66a7dad7ed3d..b75555c7d8ae 100644 --- a/crypto/asymmetric_keys/Kconfig +++ b/crypto/asymmetric_keys/Kconfig @@ -21,6 +21,17 @@ config ASYMMETRIC_PUBLIC_KEY_SUBTYPE appropriate hash algorithms (such as SHA-1) must be available. ENOPKG will be reported if the requisite algorithm is unavailable. +config ASYMMETRIC_TPM_KEY_SUBTYPE + tristate "Asymmetric TPM backed private key subtype" + depends on TCG_TPM + select CRYPTO_HMAC + select CRYPTO_SHA1 + select CRYPTO_HASH_INFO + help + This option provides support for TPM backed private key type handling. + Operations such as sign, verify, encrypt, decrypt are performed by + the TPM after the private key is loaded. + config X509_CERTIFICATE_PARSER tristate "X.509 certificate parser" depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE diff --git a/crypto/asymmetric_keys/Makefile b/crypto/asymmetric_keys/Makefile index c38424f55b08..73fbe650ff1d 100644 --- a/crypto/asymmetric_keys/Makefile +++ b/crypto/asymmetric_keys/Makefile @@ -11,6 +11,7 @@ asymmetric_keys-y := \ signature.o obj-$(CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE) += public_key.o +obj-$(CONFIG_ASYMMETRIC_TPM_KEY_SUBTYPE) += asym_tpm.o # # X.509 Certificate handling diff --git a/crypto/asymmetric_keys/asym_tpm.c b/crypto/asymmetric_keys/asym_tpm.c new file mode 100644 index 000000000000..d0b2b97e8e54 --- /dev/null +++ b/crypto/asymmetric_keys/asym_tpm.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0 +#define pr_fmt(fmt) "ASYM-TPM: "fmt +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Provide a part of a description of the key for /proc/keys. + */ +static void asym_tpm_describe(const struct key *asymmetric_key, + struct seq_file *m) +{ + struct tpm_key *tk = asymmetric_key->payload.data[asym_crypto]; + + if (!tk) + return; + + seq_printf(m, "TPM1.2/Blob"); +} + +static void asym_tpm_destroy(void *payload0, void *payload3) +{ + struct tpm_key *tk = payload0; + + if (!tk) + return; + + kfree(tk->blob); + tk->blob_len = 0; + + kfree(tk); +} + +/* Given the blob, parse it and load it into the TPM */ +struct tpm_key *tpm_key_create(const void *blob, uint32_t blob_len) +{ + int r; + struct tpm_key *tk; + + r = tpm_is_tpm2(NULL); + if (r < 0) + goto error; + + /* We don't support TPM2 yet */ + if (r > 0) { + r = -ENODEV; + goto error; + } + + r = -ENOMEM; + tk = kzalloc(sizeof(struct tpm_key), GFP_KERNEL); + if (!tk) + goto error; + + tk->blob = kmemdup(blob, blob_len, GFP_KERNEL); + if (!tk->blob) + goto error_memdup; + + tk->blob_len = blob_len; + + return tk; + +error_memdup: + kfree(tk); +error: + return ERR_PTR(r); +} +EXPORT_SYMBOL_GPL(tpm_key_create); + +/* + * TPM-based asymmetric key subtype + */ +struct asymmetric_key_subtype asym_tpm_subtype = { + .owner = THIS_MODULE, + .name = "asym_tpm", + .name_len = sizeof("asym_tpm") - 1, + .describe = asym_tpm_describe, + .destroy = asym_tpm_destroy, +}; +EXPORT_SYMBOL_GPL(asym_tpm_subtype); + +MODULE_DESCRIPTION("TPM based asymmetric key subtype"); +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2"); diff --git a/include/crypto/asym_tpm_subtype.h b/include/crypto/asym_tpm_subtype.h new file mode 100644 index 000000000000..03550b850998 --- /dev/null +++ b/include/crypto/asym_tpm_subtype.h @@ -0,0 +1,16 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifndef _LINUX_ASYM_TPM_SUBTYPE_H +#define _LINUX_ASYM_TPM_SUBTYPE_H + +#include + +struct tpm_key { + void *blob; + u32 blob_len; +}; + +struct tpm_key *tpm_key_create(const void *blob, uint32_t blob_len); + +extern struct asymmetric_key_subtype asym_tpm_subtype; + +#endif /* _LINUX_ASYM_TPM_SUBTYPE_H */ -- cgit v1.2.3