Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * xfrm6_output.c - Common IPsec encapsulation code for IPv6.
 * Copyright (C) 2002 USAGI/WIDE Project
 * Copyright (c) 2004 Herbert Xu <herbert@gondor.apana.org.au>
 */
 
#include <linux/if_ether.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/icmpv6.h>
#include <linux/netfilter_ipv6.h>
#include <net/dst.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/xfrm.h>
 
int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
<------><------><------>  u8 **prevhdr)
{
<------>return ip6_find_1stfragopt(skb, prevhdr);
}
EXPORT_SYMBOL(xfrm6_find_1stfragopt);
 
void xfrm6_local_rxpmtu(struct sk_buff *skb, u32 mtu)
{
<------>struct flowi6 fl6;
<------>struct sock *sk = skb->sk;
 
<------>fl6.flowi6_oif = sk->sk_bound_dev_if;
<------>fl6.daddr = ipv6_hdr(skb)->daddr;
 
<------>ipv6_local_rxpmtu(sk, &fl6, mtu);
}
 
void xfrm6_local_error(struct sk_buff *skb, u32 mtu)
{
<------>struct flowi6 fl6;
<------>const struct ipv6hdr *hdr;
<------>struct sock *sk = skb->sk;
 
<------>hdr = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
<------>fl6.fl6_dport = inet_sk(sk)->inet_dport;
<------>fl6.daddr = hdr->daddr;
 
<------>ipv6_local_error(sk, EMSGSIZE, &fl6, mtu);
}
 
static int __xfrm6_output_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
{
<------>return xfrm_output(sk, skb);
}
 
static int xfrm6_noneed_fragment(struct sk_buff *skb)
{
<------>struct frag_hdr *fh;
<------>u8 prevhdr = ipv6_hdr(skb)->nexthdr;
 
<------>if (prevhdr != NEXTHDR_FRAGMENT)
<------><------>return 0;
<------>fh = (struct frag_hdr *)(skb->data + sizeof(struct ipv6hdr));
<------>if (fh->nexthdr == NEXTHDR_ESP || fh->nexthdr == NEXTHDR_AUTH)
<------><------>return 1;
<------>return 0;
}
 
static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
<------>struct dst_entry *dst = skb_dst(skb);
<------>struct xfrm_state *x = dst->xfrm;
<------>unsigned int mtu;
<------>bool toobig;
 
#ifdef CONFIG_NETFILTER
<------>if (!x) {
<------><------>IP6CB(skb)->flags |= IP6SKB_REROUTED;
<------><------>return dst_output(net, sk, skb);
<------>}
#endif
 
<------>if (x->props.mode != XFRM_MODE_TUNNEL)
<------><------>goto skip_frag;
 
<------>if (skb->protocol == htons(ETH_P_IPV6))
<------><------>mtu = ip6_skb_dst_mtu(skb);
<------>else
<------><------>mtu = dst_mtu(skb_dst(skb));
 
<------>toobig = skb->len > mtu && !skb_is_gso(skb);
 
<------>if (toobig && xfrm6_local_dontfrag(skb->sk)) {
<------><------>xfrm6_local_rxpmtu(skb, mtu);
<------><------>kfree_skb(skb);
<------><------>return -EMSGSIZE;
<------>} else if (toobig && xfrm6_noneed_fragment(skb)) {
<------><------>skb->ignore_df = 1;
<------><------>goto skip_frag;
<------>} else if (!skb->ignore_df && toobig && skb->sk) {
<------><------>xfrm_local_error(skb, mtu);
<------><------>kfree_skb(skb);
<------><------>return -EMSGSIZE;
<------>}
 
<------>if (toobig || dst_allfrag(skb_dst(skb)))
<------><------>return ip6_fragment(net, sk, skb,
<------><------><------><------>    __xfrm6_output_finish);
 
skip_frag:
<------>return xfrm_output(sk, skb);
}
 
int xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
<------>return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
<------><------><------>    net, sk, skb,  skb->dev, skb_dst(skb)->dev,
<------><------><------>    __xfrm6_output,
<------><------><------>    !(IP6CB(skb)->flags & IP6SKB_REROUTED));
}