tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * IPV6 GSO/GRO offload support
3 * Linux INET6 implementation
4 *
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.
9 *
10 * TCPv6 GSO/GRO support
11 */
12#include <linux/indirect_call_wrapper.h>
13#include <linux/skbuff.h>
14#include <net/protocol.h>
15#include <net/tcp.h>
16#include <net/ip6_checksum.h>
17#include "ip6_offload.h"
18
19INDIRECT_CALLABLE_SCOPE
20struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb)
21{
22 /* Don't bother verifying checksum if we're going to flush anyway. */
23 if (!NAPI_GRO_CB(skb)->flush &&
24 skb_gro_checksum_validate(skb, IPPROTO_TCP,
25 ip6_gro_compute_pseudo)) {
26 NAPI_GRO_CB(skb)->flush = 1;
27 return NULL;
28 }
29
30 return tcp_gro_receive(head, skb);
31}
32
33INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff)
34{
35 const struct ipv6hdr *iph = ipv6_hdr(skb);
36 struct tcphdr *th = tcp_hdr(skb);
37
38 th->check = ~tcp_v6_check(skb->len - thoff, &iph->saddr,
39 &iph->daddr, 0);
40 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
41
42 return tcp_gro_complete(skb);
43}
44
45static struct sk_buff *tcp6_gso_segment(struct sk_buff *skb,
46 netdev_features_t features)
47{
48 struct tcphdr *th;
49
50 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6))
51 return ERR_PTR(-EINVAL);
52
53 if (!pskb_may_pull(skb, sizeof(*th)))
54 return ERR_PTR(-EINVAL);
55
56 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
57 const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
58 struct tcphdr *th = tcp_hdr(skb);
59
60 /* Set up pseudo header, usually expect stack to have done
61 * this.
62 */
63
64 th->check = 0;
65 skb->ip_summed = CHECKSUM_PARTIAL;
66 __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
67 }
68
69 return tcp_gso_segment(skb, features);
70}
71static const struct net_offload tcpv6_offload = {
72 .callbacks = {
73 .gso_segment = tcp6_gso_segment,
74 .gro_receive = tcp6_gro_receive,
75 .gro_complete = tcp6_gro_complete,
76 },
77};
78
79int __init tcpv6_offload_init(void)
80{
81 return inet6_add_offload(&tcpv6_offload, IPPROTO_TCP);
82}