mirror of https://github.com/hak5/openwrt-owl.git
104 lines
2.4 KiB
C
104 lines
2.4 KiB
C
/*
|
|
* Copyright (C) 2013 Gabor Juhos <juhosg@openwrt.org>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published
|
|
* by the Free Software Foundation.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mtd/mtd.h>
|
|
#include <linux/mtd/partitions.h>
|
|
#include <linux/byteorder/generic.h>
|
|
|
|
#include "mtdsplit.h"
|
|
|
|
#define SEAMA_MAGIC 0x5EA3A417
|
|
#define SEAMA_NR_PARTS 2
|
|
#define SEAMA_MIN_ROOTFS_OFFS 0x80000 /* 512KiB */
|
|
|
|
struct seama_header {
|
|
__be32 magic; /* should always be SEAMA_MAGIC. */
|
|
__be16 reserved; /* reserved for */
|
|
__be16 metasize; /* size of the META data */
|
|
__be32 size; /* size of the image */
|
|
};
|
|
|
|
static int mtdsplit_parse_seama(struct mtd_info *master,
|
|
struct mtd_partition **pparts,
|
|
struct mtd_part_parser_data *data)
|
|
{
|
|
struct seama_header hdr;
|
|
size_t hdr_len, retlen, kernel_size;
|
|
size_t rootfs_offset;
|
|
struct mtd_partition *parts;
|
|
int err;
|
|
|
|
hdr_len = sizeof(hdr);
|
|
err = mtd_read(master, 0, hdr_len, &retlen, (void *) &hdr);
|
|
if (err)
|
|
return err;
|
|
|
|
if (retlen != hdr_len)
|
|
return -EIO;
|
|
|
|
/* sanity checks */
|
|
if (be32_to_cpu(hdr.magic) != SEAMA_MAGIC)
|
|
return -EINVAL;
|
|
|
|
kernel_size = hdr_len + be32_to_cpu(hdr.size) +
|
|
be16_to_cpu(hdr.metasize);
|
|
if (kernel_size > master->size)
|
|
return -EINVAL;
|
|
|
|
/* Find the rootfs after the kernel. */
|
|
err = mtd_check_rootfs_magic(master, kernel_size);
|
|
if (!err) {
|
|
rootfs_offset = kernel_size;
|
|
} else {
|
|
/*
|
|
* The size in the header might cover the rootfs as well.
|
|
* Start the search from an arbitrary offset.
|
|
*/
|
|
err = mtd_find_rootfs_from(master, SEAMA_MIN_ROOTFS_OFFS,
|
|
master->size, &rootfs_offset);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
parts = kzalloc(SEAMA_NR_PARTS * sizeof(*parts), GFP_KERNEL);
|
|
if (!parts)
|
|
return -ENOMEM;
|
|
|
|
parts[0].name = KERNEL_PART_NAME;
|
|
parts[0].offset = 0;
|
|
parts[0].size = rootfs_offset;
|
|
|
|
parts[1].name = ROOTFS_PART_NAME;
|
|
parts[1].offset = rootfs_offset;
|
|
parts[1].size = master->size - rootfs_offset;
|
|
|
|
*pparts = parts;
|
|
return SEAMA_NR_PARTS;
|
|
}
|
|
|
|
static struct mtd_part_parser mtdsplit_seama_parser = {
|
|
.owner = THIS_MODULE,
|
|
.name = "seama-fw",
|
|
.parse_fn = mtdsplit_parse_seama,
|
|
.type = MTD_PARSER_TYPE_FIRMWARE,
|
|
};
|
|
|
|
static int __init mtdsplit_seama_init(void)
|
|
{
|
|
register_mtd_parser(&mtdsplit_seama_parser);
|
|
|
|
return 0;
|
|
}
|
|
|
|
subsys_initcall(mtdsplit_seama_init);
|