1 files changed, 186 insertions, 20 deletions

diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index 5113fa0fbcee..5a67b120c4db 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -41,6 +41,7 @@
 #include <net/addrconf.h>
 #include <net/xfrm.h>
 #include <net/net_namespace.h>
+#include <net/dst_metadata.h>
 #include <net/netns/generic.h>
 #include <linux/etherdevice.h>
 
@@ -56,6 +57,89 @@ static const struct net_device_ops xfrmi_netdev_ops;
 struct xfrmi_net {
 	/* lists for storing interfaces in use */
 	struct xfrm_if __rcu *xfrmi[XFRMI_HASH_SIZE];
+	struct xfrm_if __rcu *collect_md_xfrmi;
+};
+
+static const struct nla_policy xfrm_lwt_policy[LWT_XFRM_MAX + 1] = {
+	[LWT_XFRM_IF_ID]	= NLA_POLICY_MIN(NLA_U32, 1),
+	[LWT_XFRM_LINK]		= NLA_POLICY_MIN(NLA_U32, 1),
+};
+
+static void xfrmi_destroy_state(struct lwtunnel_state *lwt)
+{
+}
+
+static int xfrmi_build_state(struct net *net, struct nlattr *nla,
+			     unsigned int family, const void *cfg,
+			     struct lwtunnel_state **ts,
+			     struct netlink_ext_ack *extack)
+{
+	struct nlattr *tb[LWT_XFRM_MAX + 1];
+	struct lwtunnel_state *new_state;
+	struct xfrm_md_info *info;
+	int ret;
+
+	ret = nla_parse_nested(tb, LWT_XFRM_MAX, nla, xfrm_lwt_policy, extack);
+	if (ret < 0)
+		return ret;
+
+	if (!tb[LWT_XFRM_IF_ID]) {
+		NL_SET_ERR_MSG(extack, "if_id must be set");
+		return -EINVAL;
+	}
+
+	new_state = lwtunnel_state_alloc(sizeof(*info));
+	if (!new_state) {
+		NL_SET_ERR_MSG(extack, "failed to create encap info");
+		return -ENOMEM;
+	}
+
+	new_state->type = LWTUNNEL_ENCAP_XFRM;
+
+	info = lwt_xfrm_info(new_state);
+
+	info->if_id = nla_get_u32(tb[LWT_XFRM_IF_ID]);
+
+	if (tb[LWT_XFRM_LINK])
+		info->link = nla_get_u32(tb[LWT_XFRM_LINK]);
+
+	*ts = new_state;
+	return 0;
+}
+
+static int xfrmi_fill_encap_info(struct sk_buff *skb,
+				 struct lwtunnel_state *lwt)
+{
+	struct xfrm_md_info *info = lwt_xfrm_info(lwt);
+
+	if (nla_put_u32(skb, LWT_XFRM_IF_ID, info->if_id) ||
+	    (info->link && nla_put_u32(skb, LWT_XFRM_LINK, info->link)))
+		return -EMSGSIZE;
+
+	return 0;
+}
+
+static int xfrmi_encap_nlsize(struct lwtunnel_state *lwtstate)
+{
+	return nla_total_size(sizeof(u32)) + /* LWT_XFRM_IF_ID */
+		nla_total_size(sizeof(u32)); /* LWT_XFRM_LINK */
+}
+
+static int xfrmi_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b)
+{
+	struct xfrm_md_info *a_info = lwt_xfrm_info(a);
+	struct xfrm_md_info *b_info = lwt_xfrm_info(b);
+
+	return memcmp(a_info, b_info, sizeof(*a_info));
+}
+
+static const struct lwtunnel_encap_ops xfrmi_encap_ops = {
+	.build_state	= xfrmi_build_state,
+	.destroy_state	= xfrmi_destroy_state,
+	.fill_encap	= xfrmi_fill_encap_info,
+	.get_encap_size = xfrmi_encap_nlsize,
+	.cmp_encap	= xfrmi_encap_cmp,
+	.owner		= THIS_MODULE,
 };
 
 #define for_each_xfrmi_rcu(start, xi) \
@@ -77,17 +161,23 @@ static struct xfrm_if *xfrmi_lookup(struct net *net, struct xfrm_state *x)
 			return xi;
 	}
 
+	xi = rcu_dereference(xfrmn->collect_md_xfrmi);
+	if (xi && (xi->dev->flags & IFF_UP))
+		return xi;
+
 	return NULL;
 }
 
-static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
-					    unsigned short family)
+static bool xfrmi_decode_session(struct sk_buff *skb,
+				 unsigned short family,
+				 struct xfrm_if_decode_session_result *res)
 {
 	struct net_device *dev;
+	struct xfrm_if *xi;
 	int ifindex = 0;
 
 	if (!secpath_exists(skb) || !skb->dev)
-		return NULL;
+		return false;
 
 	switch (family) {
 	case AF_INET6:
@@ -107,11 +197,18 @@ static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
 	}
 
 	if (!dev || !(dev->flags & IFF_UP))
-		return NULL;
+		return false;
 	if (dev->netdev_ops != &xfrmi_netdev_ops)
-		return NULL;
+		return false;
 
-	return netdev_priv(dev);
+	xi = netdev_priv(dev);
+	res->net = xi->net;
+
+	if (xi->p.collect_md)
+		res->if_id = xfrm_input_state(skb)->if_id;
+	else
+		res->if_id = xi->p.if_id;
+	return true;
 }
 
 static void xfrmi_link(struct xfrmi_net *xfrmn, struct xfrm_if *xi)
@@ -157,7 +254,10 @@ static int xfrmi_create(struct net_device *dev)
 	if (err < 0)
 		goto out;
 
-	xfrmi_link(xfrmn, xi);
+	if (xi->p.collect_md)
+		rcu_assign_pointer(xfrmn->collect_md_xfrmi, xi);
+	else
+		xfrmi_link(xfrmn, xi);
 
 	return 0;
 
@@ -185,7 +285,10 @@ static void xfrmi_dev_uninit(struct net_device *dev)
 	struct xfrm_if *xi = netdev_priv(dev);
 	struct xfrmi_net *xfrmn = net_generic(xi->net, xfrmi_net_id);
 
-	xfrmi_unlink(xfrmn, xi);
+	if (xi->p.collect_md)
+		RCU_INIT_POINTER(xfrmn->collect_md_xfrmi, NULL);
+	else
+		xfrmi_unlink(xfrmn, xi);
 }
 
 static void xfrmi_scrub_packet(struct sk_buff *skb, bool xnet)
@@ -214,6 +317,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	struct xfrm_state *x;
 	struct xfrm_if *xi;
 	bool xnet;
+	int link;
 
 	if (err && !secpath_exists(skb))
 		return 0;
@@ -224,6 +328,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	if (!xi)
 		return 1;
 
+	link = skb->dev->ifindex;
 	dev = xi->dev;
 	skb->dev = dev;
 
@@ -254,6 +359,17 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
 	}
 
 	xfrmi_scrub_packet(skb, xnet);
+	if (xi->p.collect_md) {
+		struct metadata_dst *md_dst;
+
+		md_dst = metadata_dst_alloc(0, METADATA_XFRM, GFP_ATOMIC);
+		if (!md_dst)
+			return -ENOMEM;
+
+		md_dst->u.xfrm_info.if_id = x->if_id;
+		md_dst->u.xfrm_info.link = link;
+		skb_dst_set(skb, (struct dst_entry *)md_dst);
+	}
 	dev_sw_netstats_rx_add(dev, skb->len);
 
 	return 0;
@@ -269,10 +385,23 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	struct net_device *tdev;
 	struct xfrm_state *x;
 	int err = -1;
+	u32 if_id;
 	int mtu;
 
+	if (xi->p.collect_md) {
+		struct xfrm_md_info *md_info = skb_xfrm_md_info(skb);
+
+		if (unlikely(!md_info))
+			return -EINVAL;
+
+		if_id = md_info->if_id;
+		fl->flowi_oif = md_info->link;
+	} else {
+		if_id = xi->p.if_id;
+	}
+
 	dst_hold(dst);
-	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, xi->p.if_id);
+	dst = xfrm_lookup_with_ifid(xi->net, dst, fl, NULL, 0, if_id);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		dst = NULL;
@@ -283,7 +412,7 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 	if (!x)
 		goto tx_err_link_failure;
 
-	if (x->if_id != xi->p.if_id)
+	if (x->if_id != if_id)
 		goto tx_err_link_failure;
 
 	tdev = dst->dev;
@@ -633,6 +762,9 @@ static void xfrmi_netlink_parms(struct nlattr *data[],
 
 	if (data[IFLA_XFRM_IF_ID])
 		parms->if_id = nla_get_u32(data[IFLA_XFRM_IF_ID]);
+
+	if (data[IFLA_XFRM_COLLECT_METADATA])
+		parms->collect_md = true;
 }
 
 static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
@@ -645,14 +777,27 @@ static int xfrmi_newlink(struct net *src_net, struct net_device *dev,
 	int err;
 
 	xfrmi_netlink_parms(data, &p);
-	if (!p.if_id) {
-		NL_SET_ERR_MSG(extack, "if_id must be non zero");
-		return -EINVAL;
-	}
+	if (p.collect_md) {
+		struct xfrmi_net *xfrmn = net_generic(net, xfrmi_net_id);
 
-	xi = xfrmi_locate(net, &p);
-	if (xi)
-		return -EEXIST;
+		if (p.link || p.if_id) {
+			NL_SET_ERR_MSG(extack, "link and if_id must be zero");
+			return -EINVAL;
+		}
+
+		if (rtnl_dereference(xfrmn->collect_md_xfrmi))
+			return -EEXIST;
+
+	} else {
+		if (!p.if_id) {
+			NL_SET_ERR_MSG(extack, "if_id must be non zero");
+			return -EINVAL;
+		}
+
+		xi = xfrmi_locate(net, &p);
+		if (xi)
+			return -EEXIST;
+	}
 
 	xi = netdev_priv(dev);
 	xi->p = p;
@@ -682,12 +827,22 @@ static int xfrmi_changelink(struct net_device *dev, struct nlattr *tb[],
 		return -EINVAL;
 	}
 
+	if (p.collect_md) {
+		NL_SET_ERR_MSG(extack, "collect_md can't be changed");
+		return -EINVAL;
+	}
+
 	xi = xfrmi_locate(net, &p);
 	if (!xi) {
 		xi = netdev_priv(dev);
 	} else {
 		if (xi->dev != dev)
 			return -EEXIST;
+		if (xi->p.collect_md) {
+			NL_SET_ERR_MSG(extack,
+				       "device can't be changed to collect_md");
+			return -EINVAL;
+		}
 	}
 
 	return xfrmi_update(xi, &p);
@@ -700,6 +855,8 @@ static size_t xfrmi_get_size(const struct net_device *dev)
 		nla_total_size(4) +
 		/* IFLA_XFRM_IF_ID */
 		nla_total_size(4) +
+		/* IFLA_XFRM_COLLECT_METADATA */
+		nla_total_size(0) +
 		0;
 }
 
@@ -709,7 +866,8 @@ static int xfrmi_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	struct xfrm_if_parms *parm = &xi->p;
 
 	if (nla_put_u32(skb, IFLA_XFRM_LINK, parm->link) ||
-	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id))
+	    nla_put_u32(skb, IFLA_XFRM_IF_ID, parm->if_id) ||
+	    (xi->p.collect_md && nla_put_flag(skb, IFLA_XFRM_COLLECT_METADATA)))
 		goto nla_put_failure;
 	return 0;
 
@@ -725,8 +883,10 @@ static struct net *xfrmi_get_link_net(const struct net_device *dev)
 }
 
 static const struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
-	[IFLA_XFRM_LINK]	= { .type = NLA_U32 },
-	[IFLA_XFRM_IF_ID]	= { .type = NLA_U32 },
+	[IFLA_XFRM_UNSPEC]		= { .strict_start_type = IFLA_XFRM_COLLECT_METADATA },
+	[IFLA_XFRM_LINK]		= { .type = NLA_U32 },
+	[IFLA_XFRM_IF_ID]		= { .type = NLA_U32 },
+	[IFLA_XFRM_COLLECT_METADATA]	= { .type = NLA_FLAG },
 };
 
 static struct rtnl_link_ops xfrmi_link_ops __read_mostly = {
@@ -762,6 +922,9 @@ static void __net_exit xfrmi_exit_batch_net(struct list_head *net_exit_list)
 			     xip = &xi->next)
 				unregister_netdevice_queue(xi->dev, &list);
 		}
+		xi = rtnl_dereference(xfrmn->collect_md_xfrmi);
+		if (xi)
+			unregister_netdevice_queue(xi->dev, &list);
 	}
 	unregister_netdevice_many(&list);
 	rtnl_unlock();
@@ -999,6 +1162,8 @@ static int __init xfrmi_init(void)
 	if (err < 0)
 		goto rtnl_link_failed;
 
+	lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
+
 	xfrm_if_register_cb(&xfrm_if_cb);
 
 	return err;
@@ -1017,6 +1182,7 @@ pernet_dev_failed:
 static void __exit xfrmi_fini(void)
 {
 	xfrm_if_unregister_cb();
+	lwtunnel_encap_del_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
 	rtnl_link_unregister(&xfrmi_link_ops);
 	xfrmi4_fini();
 	xfrmi6_fini();