| /* |
| * IPV6 GSO/GRO offload support |
| * Linux INET6 implementation |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * TCPv6 GSO/GRO support |
| */ |
| #include <linux/skbuff.h> |
| #include <net/protocol.h> |
| #include <net/tcp.h> |
| #include <net/ip6_checksum.h> |
| #include "ip6_offload.h" |
| |
| static struct sk_buff **tcp6_gro_receive(struct sk_buff **head, |
| struct sk_buff *skb) |
| { |
| /* Don't bother verifying checksum if we're going to flush anyway. */ |
| if (!NAPI_GRO_CB(skb)->flush && |
| skb_gro_checksum_validate(skb, IPPROTO_TCP, |
| ip6_gro_compute_pseudo)) { |
| NAPI_GRO_CB(skb)->flush = 1; |
| return NULL; |
| } |
| |
| return tcp_gro_receive(head, skb); |
| } |
| |
| static int tcp6_gro_complete(struct sk_buff *skb, int thoff) |
| { |
| const struct ipv6hdr *iph = ipv6_hdr(skb); |
| struct tcphdr *th = tcp_hdr(skb); |
| |
| th->check = ~tcp_v6_check(skb->len - thoff, &iph->saddr, |
| &iph->daddr, 0); |
| skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6; |
| |
| return tcp_gro_complete(skb); |
| } |
| |
| static struct sk_buff *tcp6_gso_segment(struct sk_buff *skb, |
| netdev_features_t features) |
| { |
| struct tcphdr *th; |
| |
| if (!(skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)) |
| return ERR_PTR(-EINVAL); |
| |
| if (!pskb_may_pull(skb, sizeof(*th))) |
| return ERR_PTR(-EINVAL); |
| |
| if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { |
| const struct ipv6hdr *ipv6h = ipv6_hdr(skb); |
| struct tcphdr *th = tcp_hdr(skb); |
| |
| /* Set up pseudo header, usually expect stack to have done |
| * this. |
| */ |
| |
| th->check = 0; |
| skb->ip_summed = CHECKSUM_PARTIAL; |
| __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr); |
| } |
| |
| return tcp_gso_segment(skb, features); |
| } |
| static const struct net_offload tcpv6_offload = { |
| .callbacks = { |
| .gso_segment = tcp6_gso_segment, |
| .gro_receive = tcp6_gro_receive, |
| .gro_complete = tcp6_gro_complete, |
| }, |
| }; |
| |
| int __init tcpv6_offload_init(void) |
| { |
| return inet6_add_offload(&tcpv6_offload, IPPROTO_TCP); |
| } |