55 lines
1.1 KiB
C
55 lines
1.1 KiB
C
|
/* include/net/dsfield.h - Manipulation of the Differentiated Services field */
|
||
|
|
|
||
|
|
/* Written 1998-2000 by Werner Almesberger, EPFL ICA */
|
||
|
|
|
||
|
|
|
||
|
|
#ifndef __NET_DSFIELD_H
|
||
|
|
#define __NET_DSFIELD_H
|
||
|
|
|
||
|
|
#include <linux/types.h>
|
||
|
|
#include <linux/ip.h>
|
||
|
|
#include <linux/ipv6.h>
|
||
|
|
#include <asm/byteorder.h>
|
||
|
|
|
||
|
|
|
||
|
|
static inline __u8 ipv4_get_dsfield(const struct iphdr *iph)
|
||
|
|
{
|
||
|
|
return iph->tos;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h)
|
||
|
|
{
|
||
|
|
return ntohs(*(const __be16 *)ipv6h) >> 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask,
|
||
|
|
__u8 value)
|
||
|
|
{
|
||
|
|
__u32 check = ntohs((__force __be16)iph->check);
|
||
|
|
__u8 dsfield;
|
||
|
|
|
||
|
|
dsfield = (iph->tos & mask) | value;
|
||
|
|
check += iph->tos;
|
||
|
|
if ((check+1) >> 16) check = (check+1) & 0xffff;
|
||
|
|
check -= dsfield;
|
||
|
|
check += check >> 16; /* adjust carry */
|
||
|
|
iph->check = (__force __sum16)htons(check);
|
||
|
|
iph->tos = dsfield;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask,
|
||
|
|
__u8 value)
|
||
|
|
{
|
||
|
|
__u16 tmp;
|
||
|
|
|
||
|
|
tmp = ntohs(*(__be16 *) ipv6h);
|
||
|
|
tmp = (tmp & ((mask << 4) | 0xf00f)) | (value << 4);
|
||
|
|
*(__be16 *) ipv6h = htons(tmp);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
#endif
|