1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * IPV6 GSO/GRO offload support 4 * Linux INET6 implementation 5 * 6 * TCPv6 GSO/GRO support 7 */ 8 #include <linux/indirect_call_wrapper.h> 9 #include <linux/skbuff.h> 10 #include <net/protocol.h> 11 #include <net/tcp.h> 12 #include <net/ip6_checksum.h> 13 #include "ip6_offload.h" 14 15 INDIRECT_CALLABLE_SCOPE 16 struct sk_buff *tcp6_gro_receive(struct list_head *head, struct sk_buff *skb) 17 { 18 /* Don't bother verifying checksum if we're going to flush anyway. */ 19 if (!NAPI_GRO_CB(skb)->flush && 20 skb_gro_checksum_validate(skb, IPPROTO_TCP, 21 ip6_gro_compute_pseudo)) { 22 NAPI_GRO_CB(skb)->flush = 1; 23 return NULL; 24 } 25 26 return tcp_gro_receive(head, skb); 27 } 28 29 INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff) 30 { 31 const struct ipv6hdr *iph = ipv6_hdr(skb); 32 struct tcphdr *th = tcp_hdr(skb); 33 34 th->check = ~tcp_v6_check(skb->len - thoff, &iph->saddr, 35 &iph->daddr, 0); 36 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6; 37 38 return tcp_gro_complete(skb); 39 } 40 41 static struct sk_buff *tcp6_gso_segment(struct sk_buff *skb, 42 netdev_features_t features) 43 { 44 struct tcphdr *th; 45 46 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)) 47 return ERR_PTR(-EINVAL); 48 49 if (!pskb_may_pull(skb, sizeof(*th))) 50 return ERR_PTR(-EINVAL); 51 52 if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) { 53 const struct ipv6hdr *ipv6h = ipv6_hdr(skb); 54 struct tcphdr *th = tcp_hdr(skb); 55 56 /* Set up pseudo header, usually expect stack to have done 57 * this. 58 */ 59 60 th->check = 0; 61 skb->ip_summed = CHECKSUM_PARTIAL; 62 __tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr); 63 } 64 65 return tcp_gso_segment(skb, features); 66 } 67 static const struct net_offload tcpv6_offload = { 68 .callbacks = { 69 .gso_segment = tcp6_gso_segment, 70 .gro_receive = tcp6_gro_receive, 71 .gro_complete = tcp6_gro_complete, 72 }, 73 }; 74 75 int __init tcpv6_offload_init(void) 76 { 77 return inet6_add_offload(&tcpv6_offload, IPPROTO_TCP); 78 } 79