From 41e8a7c249bf50f2f719c2ff21ab92be70651f06 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Wed, 6 Nov 2019 08:06:12 +0100 Subject: efi/random: use arch-independent efi_call_proto() To handle all arch-specific peculiarities when calling an EFI protocol function, a wrapper efi_call_proto() exists on all relevant architectures. On arm/arm64, this is merely a plain function call. On x86, a special EFI entry stub needs to be used, however, as the calling convention differs. To make the efi/random stub arch-independent, use efi_call_proto() instead of the existing non-portable calls to the EFI get_rng protocol function. This also requires the addition of some typedefs. Signed-off-by: Dominik Brodowski Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/random.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/libstub/random.c b/drivers/firmware/efi/libstub/random.c index b4b1d1dcb5fd..53f1466f7de6 100644 --- a/drivers/firmware/efi/libstub/random.c +++ b/drivers/firmware/efi/libstub/random.c @@ -9,6 +9,18 @@ #include "efistub.h" +typedef struct efi_rng_protocol efi_rng_protocol_t; + +typedef struct { + u32 get_info; + u32 get_rng; +} efi_rng_protocol_32_t; + +typedef struct { + u64 get_info; + u64 get_rng; +} efi_rng_protocol_64_t; + struct efi_rng_protocol { efi_status_t (*get_info)(struct efi_rng_protocol *, unsigned long *, efi_guid_t *); @@ -28,7 +40,7 @@ efi_status_t efi_get_random_bytes(efi_system_table_t *sys_table_arg, if (status != EFI_SUCCESS) return status; - return rng->get_rng(rng, NULL, size, out); + return efi_call_proto(efi_rng_protocol, get_rng, rng, NULL, size, out); } /* @@ -161,15 +173,16 @@ efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg) if (status != EFI_SUCCESS) return status; - status = rng->get_rng(rng, &rng_algo_raw, EFI_RANDOM_SEED_SIZE, - seed->bits); + status = efi_call_proto(efi_rng_protocol, get_rng, rng, &rng_algo_raw, + EFI_RANDOM_SEED_SIZE, seed->bits); + if (status == EFI_UNSUPPORTED) /* * Use whatever algorithm we have available if the raw algorithm * is not implemented. */ - status = rng->get_rng(rng, NULL, EFI_RANDOM_SEED_SIZE, - seed->bits); + status = efi_call_proto(efi_rng_protocol, get_rng, rng, NULL, + EFI_RANDOM_SEED_SIZE, seed->bits); if (status != EFI_SUCCESS) goto err_freepool; -- cgit v1.2.3-59-g8ed1b