v4.19.13 snapshot.
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
new file mode 100644
index 0000000..d73a6d6
--- /dev/null
+++ b/net/ipv4/xfrm4_policy.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * xfrm4_policy.c
+ *
+ * Changes:
+ * Kazunori MIYAZAWA @USAGI
+ * YOSHIFUJI Hideaki @USAGI
+ * Split up af-specific portion
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/inetdevice.h>
+#include <linux/if_tunnel.h>
+#include <net/dst.h>
+#include <net/xfrm.h>
+#include <net/ip.h>
+#include <net/l3mdev.h>
+
+static struct dst_entry *__xfrm4_dst_lookup(struct net *net, struct flowi4 *fl4,
+ int tos, int oif,
+ const xfrm_address_t *saddr,
+ const xfrm_address_t *daddr,
+ u32 mark)
+{
+ struct rtable *rt;
+
+ memset(fl4, 0, sizeof(*fl4));
+ fl4->daddr = daddr->a4;
+ fl4->flowi4_tos = tos;
+ fl4->flowi4_oif = l3mdev_master_ifindex_by_index(net, oif);
+ fl4->flowi4_mark = mark;
+ if (saddr)
+ fl4->saddr = saddr->a4;
+
+ fl4->flowi4_flags = FLOWI_FLAG_SKIP_NH_OIF;
+
+ rt = __ip_route_output_key(net, fl4);
+ if (!IS_ERR(rt))
+ return &rt->dst;
+
+ return ERR_CAST(rt);
+}
+
+static struct dst_entry *xfrm4_dst_lookup(struct net *net, int tos, int oif,
+ const xfrm_address_t *saddr,
+ const xfrm_address_t *daddr,
+ u32 mark)
+{
+ struct flowi4 fl4;
+
+ return __xfrm4_dst_lookup(net, &fl4, tos, oif, saddr, daddr, mark);
+}
+
+static int xfrm4_get_saddr(struct net *net, int oif,
+ xfrm_address_t *saddr, xfrm_address_t *daddr,
+ u32 mark)
+{
+ struct dst_entry *dst;
+ struct flowi4 fl4;
+
+ dst = __xfrm4_dst_lookup(net, &fl4, 0, oif, NULL, daddr, mark);
+ if (IS_ERR(dst))
+ return -EHOSTUNREACH;
+
+ saddr->a4 = fl4.saddr;
+ dst_release(dst);
+ return 0;
+}
+
+static int xfrm4_get_tos(const struct flowi *fl)
+{
+ return IPTOS_RT_MASK & fl->u.ip4.flowi4_tos; /* Strip ECN bits */
+}
+
+static int xfrm4_init_path(struct xfrm_dst *path, struct dst_entry *dst,
+ int nfheader_len)
+{
+ return 0;
+}
+
+static int xfrm4_fill_dst(struct xfrm_dst *xdst, struct net_device *dev,
+ const struct flowi *fl)
+{
+ struct rtable *rt = (struct rtable *)xdst->route;
+ const struct flowi4 *fl4 = &fl->u.ip4;
+
+ xdst->u.rt.rt_iif = fl4->flowi4_iif;
+
+ xdst->u.dst.dev = dev;
+ dev_hold(dev);
+
+ /* Sheit... I remember I did this right. Apparently,
+ * it was magically lost, so this code needs audit */
+ xdst->u.rt.rt_is_input = rt->rt_is_input;
+ xdst->u.rt.rt_flags = rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST |
+ RTCF_LOCAL);
+ xdst->u.rt.rt_type = rt->rt_type;
+ xdst->u.rt.rt_gateway = rt->rt_gateway;
+ xdst->u.rt.rt_uses_gateway = rt->rt_uses_gateway;
+ xdst->u.rt.rt_pmtu = rt->rt_pmtu;
+ xdst->u.rt.rt_mtu_locked = rt->rt_mtu_locked;
+ INIT_LIST_HEAD(&xdst->u.rt.rt_uncached);
+ rt_add_uncached_list(&xdst->u.rt);
+
+ return 0;
+}
+
+static void
+_decode_session4(struct sk_buff *skb, struct flowi *fl, int reverse)
+{
+ const struct iphdr *iph = ip_hdr(skb);
+ u8 *xprth = skb_network_header(skb) + iph->ihl * 4;
+ struct flowi4 *fl4 = &fl->u.ip4;
+ int oif = 0;
+
+ if (skb_dst(skb))
+ oif = skb_dst(skb)->dev->ifindex;
+
+ memset(fl4, 0, sizeof(struct flowi4));
+ fl4->flowi4_mark = skb->mark;
+ fl4->flowi4_oif = reverse ? skb->skb_iif : oif;
+
+ if (!ip_is_fragment(iph)) {
+ switch (iph->protocol) {
+ case IPPROTO_UDP:
+ case IPPROTO_UDPLITE:
+ case IPPROTO_TCP:
+ case IPPROTO_SCTP:
+ case IPPROTO_DCCP:
+ if (xprth + 4 < skb->data ||
+ pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ __be16 *ports;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ ports = (__be16 *)xprth;
+
+ fl4->fl4_sport = ports[!!reverse];
+ fl4->fl4_dport = ports[!reverse];
+ }
+ break;
+
+ case IPPROTO_ICMP:
+ if (xprth + 2 < skb->data ||
+ pskb_may_pull(skb, xprth + 2 - skb->data)) {
+ u8 *icmp;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ icmp = xprth;
+
+ fl4->fl4_icmp_type = icmp[0];
+ fl4->fl4_icmp_code = icmp[1];
+ }
+ break;
+
+ case IPPROTO_ESP:
+ if (xprth + 4 < skb->data ||
+ pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ __be32 *ehdr;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ ehdr = (__be32 *)xprth;
+
+ fl4->fl4_ipsec_spi = ehdr[0];
+ }
+ break;
+
+ case IPPROTO_AH:
+ if (xprth + 8 < skb->data ||
+ pskb_may_pull(skb, xprth + 8 - skb->data)) {
+ __be32 *ah_hdr;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ ah_hdr = (__be32 *)xprth;
+
+ fl4->fl4_ipsec_spi = ah_hdr[1];
+ }
+ break;
+
+ case IPPROTO_COMP:
+ if (xprth + 4 < skb->data ||
+ pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ __be16 *ipcomp_hdr;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ ipcomp_hdr = (__be16 *)xprth;
+
+ fl4->fl4_ipsec_spi = htonl(ntohs(ipcomp_hdr[1]));
+ }
+ break;
+
+ case IPPROTO_GRE:
+ if (xprth + 12 < skb->data ||
+ pskb_may_pull(skb, xprth + 12 - skb->data)) {
+ __be16 *greflags;
+ __be32 *gre_hdr;
+
+ xprth = skb_network_header(skb) + iph->ihl * 4;
+ greflags = (__be16 *)xprth;
+ gre_hdr = (__be32 *)xprth;
+
+ if (greflags[0] & GRE_KEY) {
+ if (greflags[0] & GRE_CSUM)
+ gre_hdr++;
+ fl4->fl4_gre_key = gre_hdr[1];
+ }
+ }
+ break;
+
+ default:
+ fl4->fl4_ipsec_spi = 0;
+ break;
+ }
+ }
+ fl4->flowi4_proto = iph->protocol;
+ fl4->daddr = reverse ? iph->saddr : iph->daddr;
+ fl4->saddr = reverse ? iph->daddr : iph->saddr;
+ fl4->flowi4_tos = iph->tos;
+}
+
+static void xfrm4_update_pmtu(struct dst_entry *dst, struct sock *sk,
+ struct sk_buff *skb, u32 mtu)
+{
+ struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+ struct dst_entry *path = xdst->route;
+
+ path->ops->update_pmtu(path, sk, skb, mtu);
+}
+
+static void xfrm4_redirect(struct dst_entry *dst, struct sock *sk,
+ struct sk_buff *skb)
+{
+ struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+ struct dst_entry *path = xdst->route;
+
+ path->ops->redirect(path, sk, skb);
+}
+
+static void xfrm4_dst_destroy(struct dst_entry *dst)
+{
+ struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
+
+ dst_destroy_metrics_generic(dst);
+ if (xdst->u.rt.rt_uncached_list)
+ rt_del_uncached_list(&xdst->u.rt);
+ xfrm_dst_destroy(xdst);
+}
+
+static void xfrm4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
+ int unregister)
+{
+ if (!unregister)
+ return;
+
+ xfrm_dst_ifdown(dst, dev);
+}
+
+static struct dst_ops xfrm4_dst_ops_template = {
+ .family = AF_INET,
+ .update_pmtu = xfrm4_update_pmtu,
+ .redirect = xfrm4_redirect,
+ .cow_metrics = dst_cow_metrics_generic,
+ .destroy = xfrm4_dst_destroy,
+ .ifdown = xfrm4_dst_ifdown,
+ .local_out = __ip_local_out,
+ .gc_thresh = 32768,
+};
+
+static const struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
+ .dst_ops = &xfrm4_dst_ops_template,
+ .dst_lookup = xfrm4_dst_lookup,
+ .get_saddr = xfrm4_get_saddr,
+ .decode_session = _decode_session4,
+ .get_tos = xfrm4_get_tos,
+ .init_path = xfrm4_init_path,
+ .fill_dst = xfrm4_fill_dst,
+ .blackhole_route = ipv4_blackhole_route,
+};
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table xfrm4_policy_table[] = {
+ {
+ .procname = "xfrm4_gc_thresh",
+ .data = &init_net.xfrm.xfrm4_dst_ops.gc_thresh,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ { }
+};
+
+static __net_init int xfrm4_net_sysctl_init(struct net *net)
+{
+ struct ctl_table *table;
+ struct ctl_table_header *hdr;
+
+ table = xfrm4_policy_table;
+ if (!net_eq(net, &init_net)) {
+ table = kmemdup(table, sizeof(xfrm4_policy_table), GFP_KERNEL);
+ if (!table)
+ goto err_alloc;
+
+ table[0].data = &net->xfrm.xfrm4_dst_ops.gc_thresh;
+ }
+
+ hdr = register_net_sysctl(net, "net/ipv4", table);
+ if (!hdr)
+ goto err_reg;
+
+ net->ipv4.xfrm4_hdr = hdr;
+ return 0;
+
+err_reg:
+ if (!net_eq(net, &init_net))
+ kfree(table);
+err_alloc:
+ return -ENOMEM;
+}
+
+static __net_exit void xfrm4_net_sysctl_exit(struct net *net)
+{
+ struct ctl_table *table;
+
+ if (!net->ipv4.xfrm4_hdr)
+ return;
+
+ table = net->ipv4.xfrm4_hdr->ctl_table_arg;
+ unregister_net_sysctl_table(net->ipv4.xfrm4_hdr);
+ if (!net_eq(net, &init_net))
+ kfree(table);
+}
+#else /* CONFIG_SYSCTL */
+static inline int xfrm4_net_sysctl_init(struct net *net)
+{
+ return 0;
+}
+
+static inline void xfrm4_net_sysctl_exit(struct net *net)
+{
+}
+#endif
+
+static int __net_init xfrm4_net_init(struct net *net)
+{
+ int ret;
+
+ memcpy(&net->xfrm.xfrm4_dst_ops, &xfrm4_dst_ops_template,
+ sizeof(xfrm4_dst_ops_template));
+ ret = dst_entries_init(&net->xfrm.xfrm4_dst_ops);
+ if (ret)
+ return ret;
+
+ ret = xfrm4_net_sysctl_init(net);
+ if (ret)
+ dst_entries_destroy(&net->xfrm.xfrm4_dst_ops);
+
+ return ret;
+}
+
+static void __net_exit xfrm4_net_exit(struct net *net)
+{
+ xfrm4_net_sysctl_exit(net);
+ dst_entries_destroy(&net->xfrm.xfrm4_dst_ops);
+}
+
+static struct pernet_operations __net_initdata xfrm4_net_ops = {
+ .init = xfrm4_net_init,
+ .exit = xfrm4_net_exit,
+};
+
+static void __init xfrm4_policy_init(void)
+{
+ xfrm_policy_register_afinfo(&xfrm4_policy_afinfo, AF_INET);
+}
+
+void __init xfrm4_init(void)
+{
+ xfrm4_state_init();
+ xfrm4_policy_init();
+ xfrm4_protocol_init();
+ register_pernet_subsys(&xfrm4_net_ops);
+}