diff options
Diffstat (limited to 'replacements.c')
| -rw-r--r-- | replacements.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/replacements.c b/replacements.c index bf781a8b..469e73aa 100644 --- a/replacements.c +++ b/replacements.c @@ -78,8 +78,27 @@ replacement_start_image(EFI_HANDLE image_handle, UINTN *exit_data_size, CHAR16 * unhook_system_services(); if (image_handle == last_loaded_image) { + UINT8 retain_protocol = 0; + UINTN retain_protocol_size = sizeof(retain_protocol); + UINT32 retain_protocol_attrs = 0; + loader_is_participating = 1; - uninstall_shim_protocols(); + + /* If a boot component asks us, keep our protocol around - it will be used to + * validate further PE payloads (e.g.: by the UKI stub, before the kernel is booted). + * But also check that the variable was set by a boot component, to ensure that + * nobody at runtime can attempt to change shim's behaviour. */ + efi_status = RT->GetVariable(SHIM_RETAIN_PROTOCOL_VAR_NAME, + &SHIM_LOCK_GUID, + &retain_protocol_attrs, + &retain_protocol_size, + &retain_protocol); + if (EFI_ERROR(efi_status) || + (retain_protocol_attrs & EFI_VARIABLE_NON_VOLATILE) || + !(retain_protocol_attrs & EFI_VARIABLE_BOOTSERVICE_ACCESS) || + retain_protocol_size != sizeof(retain_protocol) || + retain_protocol == 0) + uninstall_shim_protocols(); } efi_status = BS->StartImage(image_handle, exit_data_size, exit_data); if (EFI_ERROR(efi_status)) { @@ -90,7 +109,7 @@ replacement_start_image(EFI_HANDLE image_handle, UINTN *exit_data_size, CHAR16 * console_print(L"Something has gone seriously wrong: %r\n", efi_status2); console_print(L"shim cannot continue, sorry.\n"); - msleep(5000000); + usleep(5000000); RT->ResetSystem(EfiResetShutdown, EFI_SECURITY_VIOLATION, 0, NULL); @@ -118,7 +137,7 @@ exit_boot_services(EFI_HANDLE image_key, UINTN map_key) console_print(L"Bootloader has not verified loaded image.\n"); console_print(L"System is compromised. halting.\n"); - msleep(5000000); + usleep(5000000); RT->ResetSystem(EfiResetShutdown, EFI_SECURITY_VIOLATION, 0, NULL); return EFI_SECURITY_VIOLATION; } @@ -143,7 +162,7 @@ do_exit(EFI_HANDLE ImageHandle, EFI_STATUS ExitStatus, console_print(L"Something has gone seriously wrong: %r\n", efi_status2); console_print(L"shim cannot continue, sorry.\n"); - msleep(5000000); + usleep(5000000); RT->ResetSystem(EfiResetShutdown, EFI_SECURITY_VIOLATION, 0, NULL); } |