diff options
Diffstat (limited to 'arch/s390')
-rw-r--r-- | arch/s390/Kbuild | 2 | ||||
-rw-r--r-- | arch/s390/Kconfig | 15 | ||||
-rw-r--r-- | arch/s390/crypto/Makefile | 1 | ||||
-rw-r--r-- | arch/s390/crypto/arch_random.c | 31 | ||||
-rw-r--r-- | arch/s390/include/asm/archrandom.h | 69 |
5 files changed, 117 insertions, 1 deletions
diff --git a/arch/s390/Kbuild b/arch/s390/Kbuild index e256592eb66e..eae2c64cf69d 100644 --- a/arch/s390/Kbuild +++ b/arch/s390/Kbuild @@ -1,7 +1,7 @@ obj-y += kernel/ obj-y += mm/ obj-$(CONFIG_KVM) += kvm/ -obj-$(CONFIG_CRYPTO_HW) += crypto/ +obj-y += crypto/ obj-$(CONFIG_S390_HYPFS_FS) += hypfs/ obj-$(CONFIG_APPLDATA_BASE) += appldata/ obj-y += net/ diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 249c2771be0e..ebc0bf7c84d0 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -507,6 +507,21 @@ source kernel/Kconfig.preempt source kernel/Kconfig.hz +config ARCH_RANDOM + def_bool y + prompt "s390 architectural random number generation API" + help + Enable the s390 architectural random number generation API + to provide random data for all consumers within the Linux + kernel. + + When enabled the arch_random_* functions declared in linux/random.h + are implemented. The implementation is based on the s390 CPACF + instruction subfunction TRNG which provides a real true random + number generator. + + If unsure, say Y. + endmenu menu "Memory setup" diff --git a/arch/s390/crypto/Makefile b/arch/s390/crypto/Makefile index 402c530c6da5..678d9863e3f0 100644 --- a/arch/s390/crypto/Makefile +++ b/arch/s390/crypto/Makefile @@ -10,5 +10,6 @@ obj-$(CONFIG_CRYPTO_AES_S390) += aes_s390.o paes_s390.o obj-$(CONFIG_S390_PRNG) += prng.o obj-$(CONFIG_CRYPTO_GHASH_S390) += ghash_s390.o obj-$(CONFIG_CRYPTO_CRC32_S390) += crc32-vx_s390.o +obj-$(CONFIG_ARCH_RANDOM) += arch_random.o crc32-vx_s390-y := crc32-vx.o crc32le-vx.o crc32be-vx.o diff --git a/arch/s390/crypto/arch_random.c b/arch/s390/crypto/arch_random.c new file mode 100644 index 000000000000..9317b3e645e2 --- /dev/null +++ b/arch/s390/crypto/arch_random.c @@ -0,0 +1,31 @@ +/* + * s390 arch random implementation. + * + * Copyright IBM Corp. 2017 + * Author(s): Harald Freudenberger <freude@de.ibm.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + * + */ + +#include <linux/kernel.h> +#include <linux/atomic.h> +#include <linux/static_key.h> +#include <asm/cpacf.h> + +DEFINE_STATIC_KEY_FALSE(s390_arch_random_available); + +atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0); +EXPORT_SYMBOL(s390_arch_random_counter); + +static int __init s390_arch_random_init(void) +{ + /* check if subfunction CPACF_PRNO_TRNG is available */ + if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG)) + static_branch_enable(&s390_arch_random_available); + + return 0; +} +arch_initcall(s390_arch_random_init); diff --git a/arch/s390/include/asm/archrandom.h b/arch/s390/include/asm/archrandom.h new file mode 100644 index 000000000000..6033901a40b2 --- /dev/null +++ b/arch/s390/include/asm/archrandom.h @@ -0,0 +1,69 @@ +/* + * Kernel interface for the s390 arch_random_* functions + * + * Copyright IBM Corp. 2017 + * + * Author: Harald Freudenberger <freude@de.ibm.com> + * + */ + +#ifndef _ASM_S390_ARCHRANDOM_H +#define _ASM_S390_ARCHRANDOM_H + +#ifdef CONFIG_ARCH_RANDOM + +#include <linux/static_key.h> +#include <linux/atomic.h> +#include <asm/cpacf.h> + +DECLARE_STATIC_KEY_FALSE(s390_arch_random_available); +extern atomic64_t s390_arch_random_counter; + +static void s390_arch_random_generate(u8 *buf, unsigned int nbytes) +{ + cpacf_trng(NULL, 0, buf, nbytes); + atomic64_add(nbytes, &s390_arch_random_counter); +} + +static inline bool arch_has_random(void) +{ + if (static_branch_likely(&s390_arch_random_available)) + return true; + return false; +} + +static inline bool arch_has_random_seed(void) +{ + return arch_has_random(); +} + +static inline bool arch_get_random_long(unsigned long *v) +{ + if (static_branch_likely(&s390_arch_random_available)) { + s390_arch_random_generate((u8 *)v, sizeof(*v)); + return true; + } + return false; +} + +static inline bool arch_get_random_int(unsigned int *v) +{ + if (static_branch_likely(&s390_arch_random_available)) { + s390_arch_random_generate((u8 *)v, sizeof(*v)); + return true; + } + return false; +} + +static inline bool arch_get_random_seed_long(unsigned long *v) +{ + return arch_get_random_long(v); +} + +static inline bool arch_get_random_seed_int(unsigned int *v) +{ + return arch_get_random_int(v); +} + +#endif /* CONFIG_ARCH_RANDOM */ +#endif /* _ASM_S390_ARCHRANDOM_H */ |