diff options
-rw-r--r-- | drivers/char/hw_random/Kconfig | 13 | ||||
-rw-r--r-- | drivers/char/hw_random/Makefile | 1 | ||||
-rw-r--r-- | drivers/char/hw_random/tpm-rng.c | 50 |
3 files changed, 64 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 7c0d3919..fbd9b2b 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -289,3 +289,16 @@ config HW_RANDOM_EXYNOS module will be called exynos-rng. If unsure, say Y. + +config HW_RANDOM_TPM + tristate "TPM HW Random Number Generator support" + depends on HW_RANDOM && TCG_TPM + default HW_RANDOM + ---help--- + This driver provides kernel-side support for the Random Number + Generator in the Trusted Platform Module + + To compile this driver as a module, choose M here: the + module will be called tpm-rng. + + If unsure, say Y. diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index 39a757c..1fd7eec 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -25,3 +25,4 @@ obj-$(CONFIG_HW_RANDOM_PICOXCELL) += picoxcell-rng.o obj-$(CONFIG_HW_RANDOM_PPC4XX) += ppc4xx-rng.o obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o obj-$(CONFIG_HW_RANDOM_EXYNOS) += exynos-rng.o +obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o diff --git a/drivers/char/hw_random/tpm-rng.c b/drivers/char/hw_random/tpm-rng.c new file mode 100644 index 0000000..d6d4482 --- /dev/null +++ b/drivers/char/hw_random/tpm-rng.c @@ -0,0 +1,50 @@ +/* + * Copyright (C) 2012 Kent Yoder IBM Corporation + * + * HWRNG interfaces to pull RNG data from a TPM + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <linux/module.h> +#include <linux/hw_random.h> +#include <linux/tpm.h> + +#define MODULE_NAME "tpm-rng" + +static int tpm_rng_read(struct hwrng *rng, void *data, size_t max, bool wait) +{ + return tpm_get_random(TPM_ANY_NUM, data, max); +} + +static struct hwrng tpm_rng = { + .name = MODULE_NAME, + .read = tpm_rng_read, +}; + +static int __init rng_init(void) +{ + return hwrng_register(&tpm_rng); +} +module_init(rng_init); + +static void __exit rng_exit(void) +{ + hwrng_unregister(&tpm_rng); +} +module_exit(rng_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Kent Yoder <key@linux.vnet.ibm.com>"); +MODULE_DESCRIPTION("RNG driver for TPM devices"); |