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/*
* Copyright (C) 2007 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
*
* gPXE scripts
*
*/
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <gpxe/image.h>
#include <gpxe/uri.h>
struct image_type script_image_type __image_type ( PROBE_NORMAL );
/**
* Execute script
*
* @v image Script
* @ret rc Return status code
*/
static int script_exec ( struct image *image ) {
struct uri *old_cwuri;
char cmdbuf[256];
size_t offset = 0;
size_t remaining;
size_t len;
char *eol;
int rc;
/* Temporarily de-register image, so that a "boot" command
* doesn't throw us into an execution loop. Hold a reference
* to avoid the image's being freed.
*/
image_get ( image );
unregister_image ( image );
/* Switch current working directory to be that of the script itself */
old_cwuri = uri_get ( cwuri );
churi ( image->uri );
while ( offset < image->len ) {
/* Read up to cmdbuf bytes from script into buffer */
remaining = ( image->len - offset );
len = sizeof ( cmdbuf );
if ( len > remaining )
len = remaining;
memset ( cmdbuf, 0, sizeof ( cmdbuf ) );
copy_from_user ( cmdbuf, image->data, offset, len );
/* Find end of line */
eol = memchr ( cmdbuf, '\n', sizeof ( cmdbuf ) );
if ( ! eol )
eol = memchr ( cmdbuf, '\0', sizeof ( cmdbuf ) );
if ( ! eol ) {
DBG ( "Script line too long (max %d bytes)\n",
sizeof ( cmdbuf ) );
rc = -ENOEXEC;
goto done;
}
/* Mark end of line and execute command */
*eol = '\0';
DBG ( "$ %s\n", cmdbuf );
if ( ( rc = system ( cmdbuf ) ) != 0 ) {
DBG ( "Command \"%s\" failed: %s\n",
cmdbuf, strerror ( rc ) );
goto done;
}
/* Move to next line */
offset += ( ( eol - cmdbuf ) + 1 );
}
rc = 0;
done:
/* Reset current working directory, re-register image and return */
churi ( old_cwuri );
uri_put ( old_cwuri );
register_image ( image );
image_put ( image );
return rc;
}
/**
* Load script into memory
*
* @v image Script
* @ret rc Return status code
*/
static int script_load ( struct image *image ) {
static const char magic[] = "#!gpxe\n";
char test[ sizeof ( magic ) - 1 ];
/* Check for magic signature */
copy_from_user ( test, image->data, 0, sizeof ( test ) );
if ( memcmp ( test, magic, sizeof ( test ) ) != 0 ) {
DBG ( "Invalid magic signature\n" );
return -ENOEXEC;
}
/* This is a script */
image->type = &script_image_type;
/* We don't actually load it anywhere; we will pick the lines
* out of the image as we need them.
*/
return 0;
}
/** Script image type */
struct image_type script_image_type __image_type ( PROBE_NORMAL ) = {
.name = "script",
.load = script_load,
.exec = script_exec,
};
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