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