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 * Checksumming functions for IPv6 8 * 9 * Authors: Jorge Cwik, <jorge@laser.satlink.net> 10 * Arnt Gulbrandsen, <agulbra@nvg.unit.no> 11 * Borrows very liberally from tcp.c and ip.c, see those 12 * files for more names. 13 */ 14 15 /* 16 * Fixes: 17 * 18 * Ralf Baechle : generic ipv6 checksum 19 * <ralf@waldorf-gmbh.de> 20 */ 21 22 #ifndef _CHECKSUM_IPV6_H 23 #define _CHECKSUM_IPV6_H 24 25 #include <asm/types.h> 26 #include <asm/byteorder.h> 27 #include <net/ip.h> 28 #include <asm/checksum.h> 29 #include <linux/in6.h> 30 #include <linux/tcp.h> 31 #include <linux/ipv6.h> 32 33 #ifndef _HAVE_ARCH_IPV6_CSUM 34 __sum16 csum_ipv6_magic(const struct in6_addr *saddr, 35 const struct in6_addr *daddr, 36 __u32 len, __u8 proto, __wsum csum); 37 #endif 38 39 static inline __wsum ip6_compute_pseudo(struct sk_buff *skb, int proto) 40 { 41 return ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr, 42 &ipv6_hdr(skb)->daddr, 43 skb->len, proto, 0)); 44 } 45 46 static __inline__ __sum16 tcp_v6_check(int len, 47 const struct in6_addr *saddr, 48 const struct in6_addr *daddr, 49 __wsum base) 50 { 51 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); 52 } 53 54 static inline void __tcp_v6_send_check(struct sk_buff *skb, 55 const struct in6_addr *saddr, 56 const struct in6_addr *daddr) 57 { 58 struct tcphdr *th = tcp_hdr(skb); 59 60 th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0); 61 skb->csum_start = skb_transport_header(skb) - skb->head; 62 skb->csum_offset = offsetof(struct tcphdr, check); 63 } 64 65 static inline void tcp_v6_gso_csum_prep(struct sk_buff *skb) 66 { 67 struct ipv6hdr *ipv6h = ipv6_hdr(skb); 68 struct tcphdr *th = tcp_hdr(skb); 69 70 ipv6h->payload_len = 0; 71 th->check = ~tcp_v6_check(0, &ipv6h->saddr, &ipv6h->daddr, 0); 72 } 73 74 static inline __sum16 udp_v6_check(int len, 75 const struct in6_addr *saddr, 76 const struct in6_addr *daddr, 77 __wsum base) 78 { 79 return csum_ipv6_magic(saddr, daddr, len, IPPROTO_UDP, base); 80 } 81 82 void udp6_set_csum(bool nocheck, struct sk_buff *skb, 83 const struct in6_addr *saddr, 84 const struct in6_addr *daddr, int len); 85 86 int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto); 87 #endif 88