HardenedBSD/lib/libefi/efi_getvar.c
marcel 89690f20ef Introduce libefi -- a library around EFI runtime services and protocols.
This first commit brings 3 functions for enumerating, retrieving,
adding, removing and modifying EFI variables. The immediate use of these
include the insertion of a new boot option as part of the installation
process.

This library uses ioctl(2) requests implemented by io(4) to pass the
requests down through the kernel to EFI. These ioctl requests are only
implemented on ia64, so libefi is currently only enabled on ia64. The
interface is generic and io(4) on mad64/i386 can easily be taught to
handle these once EFI support has been added to the kernel there.
2010-01-30 04:24:03 +00:00

69 lines
2.1 KiB
C

/*-
* Copyright (c) 2010 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <libefi.h>
#include <stdlib.h>
#include "libefi_int.h"
/*
* EFI_STATUS
* GetVariable(
* IN CHAR16 *VariableName,
* IN EFI_GUID *VendorGuid,
* OUT UINT32 *Attributes OPTIONAL,
* IN OUT UINTN *DataSize,
* OUT VOID *Data
* );
*/
int
efi_getvar(char *name, uuid_t *vendor, uint32_t *attrib, size_t *datasize,
void *data)
{
struct iodev_efivar_req req;
int error;
req.namesize = 0;
error = libefi_utf8_to_ucs2(name, &req.namesize, &req.name);
if (error)
return (error);
req.vendor = *vendor;
req.datasize = *datasize;
req.data = data;
req.access = IODEV_EFIVAR_GETVAR;
error = libefi_efivar(&req);
*datasize = req.datasize;
if (!error && attrib != NULL)
*attrib = req.attrib;
free(req.name);
return (error);
}