diff options
Diffstat (limited to 'shim.c')
| -rw-r--r-- | shim.c | 64 |
1 files changed, 62 insertions, 2 deletions
@@ -42,12 +42,16 @@ #include "netboot.h" #include "shim_cert.h" -#define SECOND_STAGE L"\\grub.efi" +#define DEFAULT_LOADER L"\\grub.efi" #define MOK_MANAGER L"\\MokManager.efi" static EFI_SYSTEM_TABLE *systab; static EFI_STATUS (EFIAPI *entry_point) (EFI_HANDLE image_handle, EFI_SYSTEM_TABLE *system_table); +static CHAR16 *second_stage; +static void *load_options; +static UINT32 load_options_size; + /* * The vendor certificate used for validating the second stage loader */ @@ -881,6 +885,10 @@ static EFI_STATUS handle_image (void *data, unsigned int datasize, li->ImageBase = buffer; li->ImageSize = context.ImageSize; + /* Pass the load options to the second stage loader */ + li->LoadOptions = load_options; + li->LoadOptionsSize = load_options_size; + if (!entry_point) { Print(L"Invalid entry point\n"); FreePool(buffer); @@ -1192,7 +1200,7 @@ EFI_STATUS init_grub(EFI_HANDLE image_handle) { EFI_STATUS efi_status; - efi_status = start_image(image_handle, SECOND_STAGE); + efi_status = start_image(image_handle, second_stage); if (efi_status != EFI_SUCCESS) efi_status = start_image(image_handle, MOK_MANAGER); @@ -1312,6 +1320,55 @@ static EFI_STATUS check_mok_sb (void) return status; } +/* + * Check the load options to specify the second stage loader + */ +EFI_STATUS set_second_stage (EFI_HANDLE image_handle) +{ + EFI_STATUS status; + EFI_LOADED_IMAGE *li; + CHAR16 *start = NULL, *c; + int i, remaining_size = 0; + + second_stage = DEFAULT_LOADER; + load_options = NULL; + load_options_size = 0; + + status = uefi_call_wrapper(BS->HandleProtocol, 3, image_handle, + &LoadedImageProtocol, (void **) &li); + if (status != EFI_SUCCESS) { + Print (L"Failed to get load options\n"); + return status; + } + + /* Expect a CHAR16 string with at least one CHAR16 */ + if (li->LoadOptionsSize < 4 || li->LoadOptionsSize % 2 != 0) { + return EFI_BAD_BUFFER_SIZE; + } + c = (CHAR16 *)(li->LoadOptions + (li->LoadOptionsSize - 2)); + if (*c != L'\0') { + return EFI_BAD_BUFFER_SIZE; + } + + for (i = 0; i < li->LoadOptionsSize; i += 2) { + c = (CHAR16 *)(li->LoadOptions + i); + if (*c == L' ') { + *c = L'\0'; + start = c + 1; + remaining_size = li->LoadOptionsSize - i - 2; + break; + } + } + + second_stage = (CHAR16 *)li->LoadOptions; + if (start && remaining_size > 0) { + load_options = start; + load_options_size = remaining_size; + } + + return EFI_SUCCESS; +} + EFI_STATUS efi_main (EFI_HANDLE image_handle, EFI_SYSTEM_TABLE *passed_systab) { EFI_GUID shim_lock_guid = SHIM_LOCK_GUID; @@ -1334,6 +1391,9 @@ EFI_STATUS efi_main (EFI_HANDLE image_handle, EFI_SYSTEM_TABLE *passed_systab) */ InitializeLib(image_handle, systab); + /* Set the second stage loader */ + set_second_stage (image_handle); + /* * Check whether the user has configured the system to run in * insecure mode |