/*
* Copyright (C) 2012 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <stdlib.h>
#include <errno.h>
#include <time.h>
#include <syslog.h>
#include <ipxe/uaccess.h>
#include <ipxe/image.h>
#include <ipxe/cms.h>
#include <usr/imgtrust.h>
/** @file
*
* Image trust management
*
*/
/**
* Verify image using downloaded signature
*
* @v image Image to verify
* @v signature Image containing signature
* @v name Required common name, or NULL to allow any name
* @ret rc Return status code
*/
int imgverify ( struct image *image, struct image *signature,
const char *name ) {
size_t len;
void *data;
struct cms_signature sig;
time_t now;
int rc;
/* Mark image as untrusted */
image_untrust ( image );
/* Copy signature to internal memory */
len = signature->len;
data = malloc ( len );
if ( ! data ) {
rc = -ENOMEM;
goto err_alloc;
}
copy_from_user ( data, signature->data, 0, len );
/* Parse signature */
if ( ( rc = cms_parse ( &sig, data, len ) ) != 0 )
goto err_parse;
/* Use signature to verify image */
now = time ( NULL );
if ( ( rc = cms_verify ( &sig, image->data, image->len,
name, now, NULL ) ) != 0 )
goto err_verify;
/* Mark image as trusted */
image_trust ( image );
syslog ( LOG_NOTICE, "Image \"%s\" signature OK\n", image->name );
/* Free internal copy of signature */
free ( data );
return 0;
err_verify:
err_parse:
free ( data );
err_alloc:
syslog ( LOG_ERR, "Image \"%s\" signature bad: %s\n",
image->name, strerror ( rc ) );
return rc;
}
