| 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
|---|---|
| 2 | /* include/net/dsfield.h - Manipulation of the Differentiated Services field */ |
| 3 | |
| 4 | /* Written 1998-2000 by Werner Almesberger, EPFL ICA */ |
| 5 | |
| 6 | |
| 7 | #ifndef __NET_DSFIELD_H |
| 8 | #define __NET_DSFIELD_H |
| 9 | |
| 10 | #include <linux/types.h> |
| 11 | #include <linux/ip.h> |
| 12 | #include <linux/ipv6.h> |
| 13 | #include <asm/byteorder.h> |
| 14 | |
| 15 | |
| 16 | static inline __u8 ipv4_get_dsfield(const struct iphdr *iph) |
| 17 | { |
| 18 | return iph->tos; |
| 19 | } |
| 20 | |
| 21 | |
| 22 | static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h) |
| 23 | { |
| 24 | return ntohs(*(__force const __be16 *)ipv6h) >> 4; |
| 25 | } |
| 26 | |
| 27 | |
| 28 | static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask, |
| 29 | __u8 value) |
| 30 | { |
| 31 | __u32 check = ntohs((__force __be16)iph->check); |
| 32 | __u8 dsfield; |
| 33 | |
| 34 | dsfield = (iph->tos & mask) | value; |
| 35 | check += iph->tos; |
| 36 | if ((check+1) >> 16) check = (check+1) & 0xffff; |
| 37 | check -= dsfield; |
| 38 | check += check >> 16; /* adjust carry */ |
| 39 | iph->check = (__force __sum16)htons(check); |
| 40 | iph->tos = dsfield; |
| 41 | } |
| 42 | |
| 43 | |
| 44 | static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask, |
| 45 | __u8 value) |
| 46 | { |
| 47 | __be16 *p = (__force __be16 *)ipv6h; |
| 48 | |
| 49 | *p = (*p & htons((((u16)mask << 4) | 0xf00f))) | htons((u16)value << 4); |
| 50 | } |
| 51 | |
| 52 | |
| 53 | #endif |
| 54 |