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/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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
* Lesser General Public License for more details.
*
* Copyright (C) 2015 Kay Sievers <kay@vrfy.org>
*/
#include <efi.h>
#include <efilib.h>
#include "util.h"
#include "pefile.h"
#include "linux.h"
/* magic string to find in the binary image */
static const char __attribute__((used)) magic[] = "#### LoaderInfo: stub " VERSION " ####";
static const EFI_GUID global_guid = EFI_GLOBAL_VARIABLE;
EFI_STATUS efi_main(EFI_HANDLE image, EFI_SYSTEM_TABLE *sys_table) {
EFI_LOADED_IMAGE *loaded_image;
EFI_FILE *root_dir;
CHAR16 *loaded_image_path;
CHAR8 *b;
UINTN size;
BOOLEAN secure = FALSE;
CHAR8 *sections[] = {
(UINT8 *)".cmdline",
(UINT8 *)".linux",
(UINT8 *)".initrd",
NULL
};
UINTN addrs[ELEMENTSOF(sections)-1] = {};
UINTN offs[ELEMENTSOF(sections)-1] = {};
UINTN szs[ELEMENTSOF(sections)-1] = {};
CHAR8 *cmdline = NULL;
UINTN cmdline_len;
EFI_STATUS err;
InitializeLib(image, sys_table);
err = uefi_call_wrapper(BS->OpenProtocol, 6, image, &LoadedImageProtocol, (VOID **)&loaded_image,
image, NULL, EFI_OPEN_PROTOCOL_GET_PROTOCOL);
if (EFI_ERROR(err)) {
Print(L"Error getting a LoadedImageProtocol handle: %r ", err);
uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
return err;
}
root_dir = LibOpenRoot(loaded_image->DeviceHandle);
if (!root_dir) {
Print(L"Unable to open root directory: %r ", err);
uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
return EFI_LOAD_ERROR;
}
loaded_image_path = DevicePathToStr(loaded_image->FilePath);
if (efivar_get_raw(&global_guid, L"SecureBoot", &b, &size) == EFI_SUCCESS) {
if (*b > 0)
secure = TRUE;
FreePool(b);
}
err = pefile_locate_sections(root_dir, loaded_image_path, sections, addrs, offs, szs);
if (EFI_ERROR(err)) {
Print(L"Unable to locate embedded .linux section: %r ", err);
uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
return err;
}
if (szs[0] > 0)
cmdline = (CHAR8 *)(loaded_image->ImageBase + addrs[0]);
cmdline_len = szs[0];
/* if we are not in secure boot mode, accept a custom command line and replace the built-in one */
if (!secure && loaded_image->LoadOptionsSize > 0) {
CHAR16 *options;
CHAR8 *line;
UINTN i;
options = (CHAR16 *)loaded_image->LoadOptions;
cmdline_len = (loaded_image->LoadOptionsSize / sizeof(CHAR16)) * sizeof(CHAR8);
line = AllocatePool(cmdline_len);
for (i = 0; i < cmdline_len; i++)
line[i] = options[i];
cmdline = line;
}
err = linux_exec(image, cmdline, cmdline_len,
(UINTN)loaded_image->ImageBase + addrs[1],
(UINTN)loaded_image->ImageBase + addrs[2], szs[2]);
Print(L"Execution of embedded linux image failed: %r\n", err);
uefi_call_wrapper(BS->Stall, 1, 3 * 1000 * 1000);
return err;
}
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