v4.19.13 snapshot.
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
new file mode 100644
index 0000000..9ef490d
--- /dev/null
+++ b/net/ipv6/xfrm6_input.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * xfrm6_input.c: based on net/ipv4/xfrm4_input.c
+ *
+ * Authors:
+ * Mitsuru KANDA @USAGI
+ * Kazunori MIYAZAWA @USAGI
+ * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
+ * YOSHIFUJI Hideaki @USAGI
+ * IPv6 support
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+#include <net/ipv6.h>
+#include <net/xfrm.h>
+
+int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+ return xfrm6_extract_header(skb);
+}
+
+int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi,
+ struct ip6_tnl *t)
+{
+ XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
+ XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
+ XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
+ return xfrm_input(skb, nexthdr, spi, 0);
+}
+EXPORT_SYMBOL(xfrm6_rcv_spi);
+
+static int xfrm6_transport_finish2(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ if (xfrm_trans_queue(skb, ip6_rcv_finish))
+ __kfree_skb(skb);
+ return -1;
+}
+
+int xfrm6_transport_finish(struct sk_buff *skb, int async)
+{
+ struct xfrm_offload *xo = xfrm_offload(skb);
+ int nhlen = skb->data - skb_network_header(skb);
+
+ skb_network_header(skb)[IP6CB(skb)->nhoff] =
+ XFRM_MODE_SKB_CB(skb)->protocol;
+
+#ifndef CONFIG_NETFILTER
+ if (!async)
+ return 1;
+#endif
+
+ __skb_push(skb, nhlen);
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_postpush_rcsum(skb, skb_network_header(skb), nhlen);
+
+ if (xo && (xo->flags & XFRM_GRO)) {
+ skb_mac_header_rebuild(skb);
+ skb_reset_transport_header(skb);
+ return -1;
+ }
+
+ NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
+ dev_net(skb->dev), NULL, skb, skb->dev, NULL,
+ xfrm6_transport_finish2);
+ return -1;
+}
+
+int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t)
+{
+ return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
+ 0, t);
+}
+EXPORT_SYMBOL(xfrm6_rcv_tnl);
+
+int xfrm6_rcv(struct sk_buff *skb)
+{
+ return xfrm6_rcv_tnl(skb, NULL);
+}
+EXPORT_SYMBOL(xfrm6_rcv);
+int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
+ xfrm_address_t *saddr, u8 proto)
+{
+ struct net *net = dev_net(skb->dev);
+ struct xfrm_state *x = NULL;
+ int i = 0;
+
+ if (secpath_set(skb)) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+ goto drop;
+ }
+
+ if (1 + skb->sp->len == XFRM_MAX_DEPTH) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
+ goto drop;
+ }
+
+ for (i = 0; i < 3; i++) {
+ xfrm_address_t *dst, *src;
+
+ switch (i) {
+ case 0:
+ dst = daddr;
+ src = saddr;
+ break;
+ case 1:
+ /* lookup state with wild-card source address */
+ dst = daddr;
+ src = (xfrm_address_t *)&in6addr_any;
+ break;
+ default:
+ /* lookup state with wild-card addresses */
+ dst = (xfrm_address_t *)&in6addr_any;
+ src = (xfrm_address_t *)&in6addr_any;
+ break;
+ }
+
+ x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6);
+ if (!x)
+ continue;
+
+ spin_lock(&x->lock);
+
+ if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
+ likely(x->km.state == XFRM_STATE_VALID) &&
+ !xfrm_state_check_expire(x)) {
+ spin_unlock(&x->lock);
+ if (x->type->input(x, skb) > 0) {
+ /* found a valid state */
+ break;
+ }
+ } else
+ spin_unlock(&x->lock);
+
+ xfrm_state_put(x);
+ x = NULL;
+ }
+
+ if (!x) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
+ xfrm_audit_state_notfound_simple(skb, AF_INET6);
+ goto drop;
+ }
+
+ skb->sp->xvec[skb->sp->len++] = x;
+
+ spin_lock(&x->lock);
+
+ x->curlft.bytes += skb->len;
+ x->curlft.packets++;
+
+ spin_unlock(&x->lock);
+
+ return 1;
+
+drop:
+ return -1;
+}
+EXPORT_SYMBOL(xfrm6_input_addr);