diff options
Diffstat (limited to 'qemu/roms/ipxe/src/arch/x86/interface/efi')
| -rw-r--r-- | qemu/roms/ipxe/src/arch/x86/interface/efi/efi_entropy.c | 223 | ||||
| -rw-r--r-- | qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c | 53 |
2 files changed, 0 insertions, 276 deletions
diff --git a/qemu/roms/ipxe/src/arch/x86/interface/efi/efi_entropy.c b/qemu/roms/ipxe/src/arch/x86/interface/efi/efi_entropy.c deleted file mode 100644 index a54bd12e6..000000000 --- a/qemu/roms/ipxe/src/arch/x86/interface/efi/efi_entropy.c +++ /dev/null @@ -1,223 +0,0 @@ -/* - * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License, or (at your option) any later version. - * - * 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., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301, USA. - * - * You can also choose to distribute this program under the terms of - * the Unmodified Binary Distribution Licence (as given in the file - * COPYING.UBDL), provided that you have satisfied its requirements. - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#include <errno.h> -#include <ipxe/entropy.h> -#include <ipxe/crc32.h> -#include <ipxe/efi/efi.h> -#include <ipxe/efi/Protocol/Rng.h> - -/** @file - * - * EFI entropy source - * - */ - -/** Random number generator protocol */ -static EFI_RNG_PROTOCOL *efirng; -EFI_REQUEST_PROTOCOL ( EFI_RNG_PROTOCOL, &efirng ); - -/** Minimum number of bytes to request from RNG - * - * The UEFI spec states (for no apparently good reason) that "When a - * Deterministic Random Bit Generator (DRBG) is used on the output of - * a (raw) entropy source, its security level must be at least 256 - * bits." The EDK2 codebase (mis)interprets this to mean that the - * call to GetRNG() should fail if given a buffer less than 32 bytes. - * - * Incidentally, nothing in the EFI RNG protocol provides any way to - * report the actual amount of entropy returned by GetRNG(). - */ -#define EFI_ENTROPY_RNG_LEN 32 - -/** Time (in 100ns units) to delay waiting for timer tick - * - * In theory, UEFI allows us to specify a trigger time of zero to - * simply wait for the next timer tick. In practice, specifying zero - * seems to often return immediately, which produces almost no - * entropy. Specify a delay of 1000ns to try to force an existent - * delay. - */ -#define EFI_ENTROPY_TRIGGER_TIME 10 - -/** Event used to wait for timer tick */ -static EFI_EVENT tick; - -/** - * Enable entropy gathering - * - * @ret rc Return status code - */ -static int efi_entropy_enable ( void ) { - EFI_BOOT_SERVICES *bs = efi_systab->BootServices; - EFI_STATUS efirc; - int rc; - - DBGC ( &tick, "ENTROPY %s RNG protocol\n", - ( efirng ? "has" : "has no" ) ); - - /* Create timer tick event */ - if ( ( efirc = bs->CreateEvent ( EVT_TIMER, TPL_NOTIFY, NULL, NULL, - &tick ) ) != 0 ) { - rc = -EEFI ( efirc ); - DBGC ( &tick, "ENTROPY could not create event: %s\n", - strerror ( rc ) ); - return rc; - } - - return 0; -} - -/** - * Disable entropy gathering - * - */ -static void efi_entropy_disable ( void ) { - EFI_BOOT_SERVICES *bs = efi_systab->BootServices; - - /* Close timer tick event */ - bs->CloseEvent ( tick ); -} - -/** - * Wait for a timer tick - * - * @ret low TSC low-order bits, or negative error - */ -static int efi_entropy_tick ( void ) { - EFI_BOOT_SERVICES *bs = efi_systab->BootServices; - UINTN index; - uint16_t low; - uint32_t discard_d; - EFI_STATUS efirc; - int rc; - - /* Wait for next timer tick */ - if ( ( efirc = bs->SetTimer ( tick, TimerRelative, - EFI_ENTROPY_TRIGGER_TIME ) ) != 0 ) { - rc = -EEFI ( efirc ); - DBGC ( &tick, "ENTROPY could not set timer: %s\n", - strerror ( rc ) ); - return rc; - } - if ( ( efirc = bs->WaitForEvent ( 1, &tick, &index ) ) != 0 ) { - rc = -EEFI ( efirc ); - DBGC ( &tick, "ENTROPY could not wait for timer tick: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Get current TSC low-order bits */ - __asm__ __volatile__ ( "rdtsc" : "=a" ( low ), "=d" ( discard_d ) ); - - return low; -} - -/** - * Get noise sample from timer ticks - * - * @ret noise Noise sample - * @ret rc Return status code - */ -static int efi_get_noise_ticks ( noise_sample_t *noise ) { - int before; - int after; - int rc; - - /* Wait for a timer tick */ - before = efi_entropy_tick(); - if ( before < 0 ) { - rc = before; - return rc; - } - - /* Wait for another timer tick */ - after = efi_entropy_tick(); - if ( after < 0 ) { - rc = after; - return rc; - } - - /* Use TSC delta as noise sample */ - *noise = ( after - before ); - - return 0; -} - -/** - * Get noise sample from RNG protocol - * - * @ret noise Noise sample - * @ret rc Return status code - */ -static int efi_get_noise_rng ( noise_sample_t *noise ) { - uint8_t buf[EFI_ENTROPY_RNG_LEN]; - EFI_STATUS efirc; - int rc; - - /* Fail if we have no EFI RNG protocol */ - if ( ! efirng ) - return -ENOTSUP; - - /* Get the minimum allowed number of random bytes */ - if ( ( efirc = efirng->GetRNG ( efirng, NULL, EFI_ENTROPY_RNG_LEN, - buf ) ) != 0 ) { - rc = -EEFI ( efirc ); - DBGC ( &tick, "ENTROPY could not read from RNG: %s\n", - strerror ( rc ) ); - return rc; - } - - /* Reduce random bytes to a single noise sample. This seems - * like overkill, but we have no way of knowing how much - * entropy is actually present in the bytes returned by the - * RNG protocol. - */ - *noise = crc32_le ( 0, buf, sizeof ( buf ) ); - - return 0; -} - -/** - * Get noise sample - * - * @ret noise Noise sample - * @ret rc Return status code - */ -static int efi_get_noise ( noise_sample_t *noise ) { - int rc; - - /* Try RNG first, falling back to timer ticks */ - if ( ( ( rc = efi_get_noise_rng ( noise ) ) != 0 ) && - ( ( rc = efi_get_noise_ticks ( noise ) ) != 0 ) ) - return rc; - - return 0; -} - -PROVIDE_ENTROPY_INLINE ( efi, min_entropy_per_sample ); -PROVIDE_ENTROPY ( efi, entropy_enable, efi_entropy_enable ); -PROVIDE_ENTROPY ( efi, entropy_disable, efi_entropy_disable ); -PROVIDE_ENTROPY ( efi, get_noise, efi_get_noise ); diff --git a/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c b/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c deleted file mode 100644 index 3ebf0bd68..000000000 --- a/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c +++ /dev/null @@ -1,53 +0,0 @@ -/* - * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of the - * License, or any later version. - * - * 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., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301, USA. - * - * You can also choose to distribute this program under the terms of - * the Unmodified Binary Distribution Licence (as given in the file - * COPYING.UBDL), provided that you have satisfied its requirements. - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#include <ipxe/nap.h> -#include <ipxe/efi/efi.h> - -/** @file - * - * iPXE CPU sleeping API for EFI - * - */ - -/** - * Sleep until next interrupt - * - */ -static void efix86_cpu_nap ( void ) { - /* - * I can't find any EFI API that allows us to put the CPU to - * sleep. The CpuSleep() function is defined in CpuLib.h, but - * isn't part of any exposed protocol so we have no way to - * call it. - * - * The EFI shell doesn't seem to bother sleeping the CPU; it - * just sits there idly burning power. - * - */ - __asm__ __volatile__ ( "hlt" ); -} - -PROVIDE_NAP ( efix86, cpu_nap, efix86_cpu_nap ); |