Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
awilliam
GitHub Repository: awilliam/linux-vfio
 Path: blob/master/include/net/dsfield.h
10817 views
1
/* include/net/dsfield.h - Manipulation of the Differentiated Services field */

2


3
/* Written 1998-2000 by Werner Almesberger, EPFL ICA */

4


5


6
#ifndef __NET_DSFIELD_H

7
#define __NET_DSFIELD_H

8


9
#include <linux/types.h>

10
#include <linux/ip.h>

11
#include <linux/ipv6.h>

12
#include <asm/byteorder.h>

13


14


15
static inline __u8 ipv4_get_dsfield(const struct iphdr *iph)

16
{

17
	return iph->tos;

18
}

19


20


21
static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h)

22
{

23
	return ntohs(*(const __be16 *)ipv6h) >> 4;

24
}

25


26


27
static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask,

28
    __u8 value)

29
{

30
        __u32 check = ntohs((__force __be16)iph->check);

31
	__u8 dsfield;

32


33
	dsfield = (iph->tos & mask) | value;

34
	check += iph->tos;

35
	if ((check+1) >> 16) check = (check+1) & 0xffff;

36
	check -= dsfield;

37
	check += check >> 16; /* adjust carry */

38
	iph->check = (__force __sum16)htons(check);

39
	iph->tos = dsfield;

40
}

41


42


43
static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask,

44
    __u8 value)

45
{

46
        __u16 tmp;

47


48
	tmp = ntohs(*(__be16 *) ipv6h);

49
	tmp = (tmp & ((mask << 4) | 0xf00f)) | (value << 4);

50
	*(__be16 *) ipv6h = htons(tmp);

51
}

52


53


54
#endif

55


56