2 * IPV6 GSO/GRO offload support
3 * Linux INET6 implementation
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
10 * TCPv6 GSO/GRO support
12 #include <linux/skbuff.h>
13 #include <net/protocol.h>
15 #include <net/ip6_checksum.h>
16 #include "ip6_offload.h"
18 static int tcp_v6_gso_send_check(struct sk_buff *skb)
20 const struct ipv6hdr *ipv6h;
23 if (!pskb_may_pull(skb, sizeof(*th)))
26 ipv6h = ipv6_hdr(skb);
30 skb->ip_summed = CHECKSUM_PARTIAL;
31 __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
35 static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
38 const struct ipv6hdr *iph = skb_gro_network_header(skb);
41 /* Don't bother verifying checksum if we're going to flush anyway. */
42 if (NAPI_GRO_CB(skb)->flush)
47 switch (skb->ip_summed) {
49 wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb),
54 case CHECKSUM_COMPLETE:
55 if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
57 skb->ip_summed = CHECKSUM_UNNECESSARY;
61 NAPI_GRO_CB(skb)->flush = 1;
66 return tcp_gro_receive(head, skb);
69 static int tcp6_gro_complete(struct sk_buff *skb)
71 const struct ipv6hdr *iph = ipv6_hdr(skb);
72 struct tcphdr *th = tcp_hdr(skb);
74 th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
75 &iph->saddr, &iph->daddr, 0);
76 skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
78 return tcp_gro_complete(skb);
81 static const struct net_offload tcpv6_offload = {
83 .gso_send_check = tcp_v6_gso_send_check,
84 .gso_segment = tcp_gso_segment,
85 .gro_receive = tcp6_gro_receive,
86 .gro_complete = tcp6_gro_complete,
90 int __init tcpv6_offload_init(void)
92 return inet6_add_offload(&tcpv6_offload, IPPROTO_TCP);