| 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
|---|---|
| 2 | /* |
| 3 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
| 4 | * operating system. INET is implemented using the BSD Socket |
| 5 | * interface as the means of communication with the user level. |
| 6 | * |
| 7 | * Definitions for the IP protocol. |
| 8 | * |
| 9 | * Version: @(#)ip.h 1.0.2 04/28/93 |
| 10 | * |
| 11 | * Authors: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
| 12 | */ |
| 13 | #ifndef _LINUX_IP_H |
| 14 | #define _LINUX_IP_H |
| 15 | |
| 16 | #include <linux/skbuff.h> |
| 17 | #include <uapi/linux/ip.h> |
| 18 | |
| 19 | static inline struct iphdr *ip_hdr(const struct sk_buff *skb) |
| 20 | { |
| 21 | return (struct iphdr *)skb_network_header(skb); |
| 22 | } |
| 23 | |
| 24 | static inline struct iphdr *inner_ip_hdr(const struct sk_buff *skb) |
| 25 | { |
| 26 | return (struct iphdr *)skb_inner_network_header(skb); |
| 27 | } |
| 28 | |
| 29 | static inline struct iphdr *ipip_hdr(const struct sk_buff *skb) |
| 30 | { |
| 31 | return (struct iphdr *)skb_transport_header(skb); |
| 32 | } |
| 33 | |
| 34 | static inline unsigned int ip_transport_len(const struct sk_buff *skb) |
| 35 | { |
| 36 | return ntohs(ip_hdr(skb)->tot_len) - skb_network_header_len(skb); |
| 37 | } |
| 38 | |
| 39 | static inline unsigned int iph_totlen(const struct sk_buff *skb, const struct iphdr *iph) |
| 40 | { |
| 41 | u32 len = ntohs(iph->tot_len); |
| 42 | |
| 43 | return (len || !skb_is_gso(skb) || !skb_is_gso_tcp(skb)) ? |
| 44 | len : skb->len - skb_network_offset(skb); |
| 45 | } |
| 46 | |
| 47 | static inline unsigned int skb_ip_totlen(const struct sk_buff *skb) |
| 48 | { |
| 49 | return iph_totlen(skb, iph: ip_hdr(skb)); |
| 50 | } |
| 51 | |
| 52 | /* IPv4 datagram length is stored into 16bit field (tot_len) */ |
| 53 | #define IP_MAX_MTU 0xFFFFU |
| 54 | |
| 55 | static inline void iph_set_totlen(struct iphdr *iph, unsigned int len) |
| 56 | { |
| 57 | iph->tot_len = len <= IP_MAX_MTU ? htons(len) : 0; |
| 58 | } |
| 59 | #endif /* _LINUX_IP_H */ |
| 60 |