diff options
author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2016-01-10 11:29:07 +0100 |
---|---|---|
committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-02-24 15:57:28 +0100 |
commit | e4fbf4767440472f9d23b0f25a2b905e1c63b6a8 (patch) | |
tree | d1f6ba26628fce6a1aee36e81ab754443729cbcf /drivers/firmware | |
parent | arm64: kaslr: randomize the linear region (diff) | |
download | linux-e4fbf4767440472f9d23b0f25a2b905e1c63b6a8.tar.xz linux-e4fbf4767440472f9d23b0f25a2b905e1c63b6a8.zip |
efi: stub: implement efi_get_random_bytes() based on EFI_RNG_PROTOCOL
This exposes the firmware's implementation of EFI_RNG_PROTOCOL via a new
function efi_get_random_bytes().
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'drivers/firmware')
-rw-r--r-- | drivers/firmware/efi/libstub/Makefile | 2 | ||||
-rw-r--r-- | drivers/firmware/efi/libstub/efistub.h | 3 | ||||
-rw-r--r-- | drivers/firmware/efi/libstub/random.c | 35 |
3 files changed, 39 insertions, 1 deletions
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index aaf9c0bab42e..ad077944aa0e 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -36,7 +36,7 @@ lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \ $(patsubst %.c,lib-%.o,$(arm-deps)) lib-$(CONFIG_ARM) += arm32-stub.o -lib-$(CONFIG_ARM64) += arm64-stub.o +lib-$(CONFIG_ARM64) += arm64-stub.o random.o CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) # diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index 6b6548fda089..206b7252b9d1 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -43,4 +43,7 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size, unsigned long desc_size, efi_memory_desc_t *runtime_map, int *count); +efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table, + unsigned long size, u8 *out); + #endif diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c new file mode 100644 index 000000000000..97941ee5954f --- /dev/null +++ b/drivers/firmware/efi/libstub/random.c @@ -0,0 +1,35 @@ +/* + * Copyright (C) 2016 Linaro Ltd; <ard.biesheuvel@linaro.org> + * + * 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. + * + */ + +#include <linux/efi.h> +#include <asm/efi.h> + +#include "efistub.h" + +struct efi_rng_protocol { + efi_status_t (*get_info)(struct efi_rng_protocol *, + unsigned long *, efi_guid_t *); + efi_status_t (*get_rng)(struct efi_rng_protocol *, + efi_guid_t *, unsigned long, u8 *out); +}; + +efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg, + unsigned long size, u8 *out) +{ + efi_guid_t rng_proto = EFI_RNG_PROTOCOL_GUID; + efi_status_t status; + struct efi_rng_protocol *rng; + + status = efi_call_early(locate_protocol, &rng_proto, NULL, + (void **)&rng); + if (status != EFI_SUCCESS) + return status; + + return rng->get_rng(rng, NULL, size, out); +} |