1 /* include/net/dsfield.h - Manipulation of the Differentiated Services field */
3 /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
6 #ifndef __NET_DSFIELD_H
7 #define __NET_DSFIELD_H
9 #include <linux/types.h>
11 #include <linux/ipv6.h>
12 #include <asm/byteorder.h>
15 static inline __u8 ipv4_get_dsfield(const struct iphdr *iph)
21 static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h)
23 return ntohs(*(const __be16 *)ipv6h) >> 4;
27 static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask,
30 __u32 check = ntohs((__force __be16)iph->check);
33 dsfield = (iph->tos & mask) | value;
35 if ((check+1) >> 16) check = (check+1) & 0xffff;
37 check += check >> 16; /* adjust carry */
38 iph->check = (__force __sum16)htons(check);
43 static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask,
48 tmp = ntohs(*(__be16 *) ipv6h);
49 tmp = (tmp & ((mask << 4) | 0xf00f)) | (value << 4);
50 *(__be16 *) ipv6h = htons(tmp);