Gabor Juhos
12 years ago
parent
2323120d5e
commit
ccabe4a1b4
@ -0,0 +1,100 @@ |
||||
/*
|
||||
* RouterBoot helper routines |
||||
* |
||||
* Copyright (C) 2012 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/kernel.h> |
||||
#include <linux/errno.h> |
||||
#include <linux/routerboot.h> |
||||
|
||||
#include "routerboot.h" |
||||
|
||||
static u32 get_u32(void *buf) |
||||
{ |
||||
u8 *p = buf; |
||||
|
||||
return ((u32) p[3] + ((u32) p[2] << 8) + ((u32) p[1] << 16) + |
||||
((u32) p[0] << 24)); |
||||
} |
||||
|
||||
static u16 get_u16(void *buf) |
||||
{ |
||||
u8 *p = buf; |
||||
|
||||
return (u16) p[1] + ((u16) p[0] << 8); |
||||
} |
||||
|
||||
__init int |
||||
routerboot_find_tag(u8 *buf, unsigned int buflen, u16 tag_id, |
||||
u8 **tag_data, u16 *tag_len) |
||||
{ |
||||
uint32_t magic; |
||||
int ret; |
||||
|
||||
if (buflen < 4) |
||||
return -EINVAL; |
||||
|
||||
magic = get_u32(buf); |
||||
switch (magic) { |
||||
case RB_MAGIC_HARD: |
||||
/* skip magic value */ |
||||
buf += 4; |
||||
buflen -= 4; |
||||
break; |
||||
|
||||
case RB_MAGIC_SOFT: |
||||
if (buflen < 8) |
||||
return -EINVAL; |
||||
|
||||
/* skip magic and CRC value */ |
||||
buf += 8; |
||||
buflen -= 8; |
||||
|
||||
break; |
||||
|
||||
default: |
||||
return -EINVAL; |
||||
} |
||||
|
||||
ret = -ENOENT; |
||||
while (buflen > 2) { |
||||
u16 id; |
||||
u16 len; |
||||
|
||||
len = get_u16(buf); |
||||
buf += 2; |
||||
buflen -= 2; |
||||
|
||||
if (buflen < 2) |
||||
break; |
||||
|
||||
id = get_u16(buf); |
||||
buf += 2; |
||||
buflen -= 2; |
||||
|
||||
if (id == RB_ID_TERMINATOR) |
||||
break; |
||||
|
||||
if (buflen < len) |
||||
break; |
||||
|
||||
if (id == tag_id) { |
||||
if (tag_len) |
||||
*tag_len = len; |
||||
if (tag_data) |
||||
*tag_data = buf; |
||||
ret = 0; |
||||
break; |
||||
} |
||||
|
||||
buf += len; |
||||
buflen -= len; |
||||
} |
||||
|
||||
return ret; |
||||
} |
||||
@ -0,0 +1,26 @@ |
||||
/*
|
||||
* RouterBoot definitions |
||||
* |
||||
* Copyright (C) 2012 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. |
||||
*/ |
||||
|
||||
#ifndef _ATH79_ROUTERBOOT_H_ |
||||
#define _ATH79_ROUTERBOOT_H_ |
||||
|
||||
#ifdef CONFIG_ATH79_ROUTERBOOT |
||||
int routerboot_find_tag(u8 *buf, unsigned int buflen, u16 tag_id, |
||||
u8 **tag_data, u16 *tag_len); |
||||
#else |
||||
static inline int |
||||
routerboot_find_tag(u8 *buf, unsigned int buflen, u16 tag_id, |
||||
u8 **tag_data, u16 *tag_len) |
||||
{ |
||||
return -ENOENT; |
||||
} |
||||
#endif |
||||
|
||||
#endif /* _ATH79_ROUTERBOOT_H_ */ |
||||
Loading…
Reference in new issue