Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
One patch to rename a newly introduced struct. The rest is
the rework of the IPsec virtual tunnel interface for ipv6 to
support inter address family tunneling and namespace crossing.

1) Rename the newly introduced struct xfrm_filter to avoid a
   conflict with iproute2. From Nicolas Dichtel.

2) Introduce xfrm_input_afinfo to access the address family
   dependent tunnel callback functions properly.

3) Add and use a IPsec protocol multiplexer for ipv6.

4) Remove dst_entry caching. vti can lookup multiple different
   dst entries, dependent of the configured xfrm states. Therefore
   it does not make to cache a dst_entry.

5) Remove caching of flow informations. vti6 does not use the the
   tunnel endpoint addresses to do route and xfrm lookups.

6) Update the vti6 to use its own receive hook.

7) Remove the now unused xfrm_tunnel_notifier. This was used from vti
   and is replaced by the IPsec protocol multiplexer hooks.

8) Support inter address family tunneling for vti6.

9) Check if the tunnel endpoints of the xfrm state and the vti interface
   are matching and return an error otherwise.

10) Enable namespace crossing for vti devices.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 217 insertions, 91 deletions

diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
index 864914399391..b7c0f827140b 100644
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -278,7 +278,6 @@ static void vti6_dev_uninit(struct net_device *dev)
 		RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
 	else
 		vti6_tnl_unlink(ip6n, t);
-	ip6_tnl_dst_reset(t);
 	dev_put(dev);
 }
 
@@ -288,11 +287,8 @@ static int vti6_rcv(struct sk_buff *skb)
 	const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
 
 	rcu_read_lock();
-
 	if ((t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr,
 				 &ipv6h->daddr)) != NULL) {
-		struct pcpu_sw_netstats *tstats;
-
 		if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
 			rcu_read_unlock();
 			goto discard;
@@ -309,27 +305,58 @@ static int vti6_rcv(struct sk_buff *skb)
 			goto discard;
 		}
 
-		tstats = this_cpu_ptr(t->dev->tstats);
-		u64_stats_update_begin(&tstats->syncp);
-		tstats->rx_packets++;
-		tstats->rx_bytes += skb->len;
-		u64_stats_update_end(&tstats->syncp);
-
-		skb->mark = 0;
-		secpath_reset(skb);
-		skb->dev = t->dev;
+		XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
+		skb->mark = be32_to_cpu(t->parms.i_key);
 
 		rcu_read_unlock();
-		return 0;
+
+		return xfrm6_rcv(skb);
 	}
 	rcu_read_unlock();
-	return 1;
-
+	return -EINVAL;
 discard:
 	kfree_skb(skb);
 	return 0;
 }
 
+static int vti6_rcv_cb(struct sk_buff *skb, int err)
+{
+	unsigned short family;
+	struct net_device *dev;
+	struct pcpu_sw_netstats *tstats;
+	struct xfrm_state *x;
+	struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
+
+	if (!t)
+		return 1;
+
+	dev = t->dev;
+
+	if (err) {
+		dev->stats.rx_errors++;
+		dev->stats.rx_dropped++;
+
+		return 0;
+	}
+
+	x = xfrm_input_state(skb);
+	family = x->inner_mode->afinfo->family;
+
+	if (!xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family))
+		return -EPERM;
+
+	skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
+	skb->dev = dev;
+
+	tstats = this_cpu_ptr(dev->tstats);
+	u64_stats_update_begin(&tstats->syncp);
+	tstats->rx_packets++;
+	tstats->rx_bytes += skb->len;
+	u64_stats_update_end(&tstats->syncp);
+
+	return 0;
+}
+
 /**
  * vti6_addr_conflict - compare packet addresses to tunnel's own
  *   @t: the outgoing tunnel device
@@ -349,44 +376,56 @@ vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
 	return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
 }
 
+static bool vti6_state_check(const struct xfrm_state *x,
+			     const struct in6_addr *dst,
+			     const struct in6_addr *src)
+{
+	xfrm_address_t *daddr = (xfrm_address_t *)dst;
+	xfrm_address_t *saddr = (xfrm_address_t *)src;
+
+	/* if there is no transform then this tunnel is not functional.
+	 * Or if the xfrm is not mode tunnel.
+	 */
+	if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
+	    x->props.family != AF_INET6)
+		return false;
+
+	if (ipv6_addr_any(dst))
+		return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
+
+	if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
+		return false;
+
+	return true;
+}
+
 /**
  * vti6_xmit - send a packet
  *   @skb: the outgoing socket buffer
  *   @dev: the outgoing tunnel device
+ *   @fl: the flow informations for the xfrm_lookup
  **/
-static int vti6_xmit(struct sk_buff *skb, struct net_device *dev)
+static int
+vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
 {
-	struct net *net = dev_net(dev);
 	struct ip6_tnl *t = netdev_priv(dev);
 	struct net_device_stats *stats = &t->dev->stats;
-	struct dst_entry *dst = NULL, *ndst = NULL;
-	struct flowi6 fl6;
-	struct ipv6hdr *ipv6h = ipv6_hdr(skb);
+	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *tdev;
 	int err = -1;
 
-	if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
-	    !ip6_tnl_xmit_ctl(t) || vti6_addr_conflict(t, ipv6h))
-		return err;
-
-	dst = ip6_tnl_dst_check(t);
-	if (!dst) {
-		memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6));
-
-		ndst = ip6_route_output(net, NULL, &fl6);
+	if (!dst)
+		goto tx_err_link_failure;
 
-		if (ndst->error)
-			goto tx_err_link_failure;
-		ndst = xfrm_lookup(net, ndst, flowi6_to_flowi(&fl6), NULL, 0);
-		if (IS_ERR(ndst)) {
-			err = PTR_ERR(ndst);
-			ndst = NULL;
-			goto tx_err_link_failure;
-		}
-		dst = ndst;
+	dst_hold(dst);
+	dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
+	if (IS_ERR(dst)) {
+		err = PTR_ERR(dst);
+		dst = NULL;
+		goto tx_err_link_failure;
 	}
 
-	if (!dst->xfrm || dst->xfrm->props.mode != XFRM_MODE_TUNNEL)
+	if (!vti6_state_check(dst->xfrm, &t->parms.raddr, &t->parms.laddr))
 		goto tx_err_link_failure;
 
 	tdev = dst->dev;
@@ -398,14 +437,21 @@ static int vti6_xmit(struct sk_buff *skb, struct net_device *dev)
 		goto tx_err_dst_release;
 	}
 
+	skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
+	skb_dst_set(skb, dst);
+	skb->dev = skb_dst(skb)->dev;
 
-	skb_dst_drop(skb);
-	skb_dst_set_noref(skb, dst);
+	err = dst_output(skb);
+	if (net_xmit_eval(err) == 0) {
+		struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
 
-	ip6tunnel_xmit(skb, dev);
-	if (ndst) {
-		dev->mtu = dst_mtu(ndst);
-		ip6_tnl_dst_store(t, ndst);
+		u64_stats_update_begin(&tstats->syncp);
+		tstats->tx_bytes += skb->len;
+		tstats->tx_packets++;
+		u64_stats_update_end(&tstats->syncp);
+	} else {
+		stats->tx_errors++;
+		stats->tx_aborted_errors++;
 	}
 
 	return 0;
@@ -413,7 +459,7 @@ tx_err_link_failure:
 	stats->tx_carrier_errors++;
 	dst_link_failure(skb);
 tx_err_dst_release:
-	dst_release(ndst);
+	dst_release(dst);
 	return err;
 }
 
@@ -422,16 +468,33 @@ vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ip6_tnl *t = netdev_priv(dev);
 	struct net_device_stats *stats = &t->dev->stats;
+	struct ipv6hdr *ipv6h;
+	struct flowi fl;
 	int ret;
 
+	memset(&fl, 0, sizeof(fl));
+	skb->mark = be32_to_cpu(t->parms.o_key);
+
 	switch (skb->protocol) {
 	case htons(ETH_P_IPV6):
-		ret = vti6_xmit(skb, dev);
+		ipv6h = ipv6_hdr(skb);
+
+		if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
+		    !ip6_tnl_xmit_ctl(t) || vti6_addr_conflict(t, ipv6h))
+			goto tx_err;
+
+		xfrm_decode_session(skb, &fl, AF_INET6);
+		memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
+		break;
+	case htons(ETH_P_IP):
+		xfrm_decode_session(skb, &fl, AF_INET);
+		memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
 		break;
 	default:
 		goto tx_err;
 	}
 
+	ret = vti6_xmit(skb, dev, &fl);
 	if (ret < 0)
 		goto tx_err;
 
@@ -444,24 +507,66 @@ tx_err:
 	return NETDEV_TX_OK;
 }
 
+static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+		    u8 type, u8 code, int offset, __be32 info)
+{
+	__be32 spi;
+	struct xfrm_state *x;
+	struct ip6_tnl *t;
+	struct ip_esp_hdr *esph;
+	struct ip_auth_hdr *ah;
+	struct ip_comp_hdr *ipch;
+	struct net *net = dev_net(skb->dev);
+	const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
+	int protocol = iph->nexthdr;
+
+	t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
+	if (!t)
+		return -1;
+
+	switch (protocol) {
+	case IPPROTO_ESP:
+		esph = (struct ip_esp_hdr *)(skb->data + offset);
+		spi = esph->spi;
+		break;
+	case IPPROTO_AH:
+		ah = (struct ip_auth_hdr *)(skb->data + offset);
+		spi = ah->spi;
+		break;
+	case IPPROTO_COMP:
+		ipch = (struct ip_comp_hdr *)(skb->data + offset);
+		spi = htonl(ntohs(ipch->cpi));
+		break;
+	default:
+		return 0;
+	}
+
+	if (type != ICMPV6_PKT_TOOBIG &&
+	    type != NDISC_REDIRECT)
+		return 0;
+
+	x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
+			      spi, protocol, AF_INET6);
+	if (!x)
+		return 0;
+
+	if (type == NDISC_REDIRECT)
+		ip6_redirect(skb, net, skb->dev->ifindex, 0);
+	else
+		ip6_update_pmtu(skb, net, info, 0, 0);
+	xfrm_state_put(x);
+
+	return 0;
+}
+
 static void vti6_link_config(struct ip6_tnl *t)
 {
-	struct dst_entry *dst;
 	struct net_device *dev = t->dev;
 	struct __ip6_tnl_parm *p = &t->parms;
-	struct flowi6 *fl6 = &t->fl.u.ip6;
 
 	memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
 	memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
 
-	/* Set up flowi template */
-	fl6->saddr = p->laddr;
-	fl6->daddr = p->raddr;
-	fl6->flowi6_oif = p->link;
-	fl6->flowi6_mark = be32_to_cpu(p->i_key);
-	fl6->flowi6_proto = p->proto;
-	fl6->flowlabel = 0;
-
 	p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
 		      IP6_TNL_F_CAP_PER_PACKET);
 	p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
@@ -472,28 +577,6 @@ static void vti6_link_config(struct ip6_tnl *t)
 		dev->flags &= ~IFF_POINTOPOINT;
 
 	dev->iflink = p->link;
-
-	if (p->flags & IP6_TNL_F_CAP_XMIT) {
-
-		dst = ip6_route_output(dev_net(dev), NULL, fl6);
-		if (dst->error)
-			return;
-
-		dst = xfrm_lookup(dev_net(dev), dst, flowi6_to_flowi(fl6),
-				  NULL, 0);
-		if (IS_ERR(dst))
-			return;
-
-		if (dst->dev) {
-			dev->hard_header_len = dst->dev->hard_header_len;
-
-			dev->mtu = dst_mtu(dst);
-
-			if (dev->mtu < IPV6_MIN_MTU)
-				dev->mtu = IPV6_MIN_MTU;
-		}
-		dst_release(dst);
-	}
 }
 
 /**
@@ -720,7 +803,6 @@ static void vti6_dev_setup(struct net_device *dev)
 	t = netdev_priv(dev);
 	dev->flags |= IFF_NOARP;
 	dev->addr_len = sizeof(struct in6_addr);
-	dev->features |= NETIF_F_NETNS_LOCAL;
 	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
 }
 
@@ -908,11 +990,6 @@ static struct rtnl_link_ops vti6_link_ops __read_mostly = {
 	.fill_info	= vti6_fill_info,
 };
 
-static struct xfrm_tunnel_notifier vti6_handler __read_mostly = {
-	.handler	= vti6_rcv,
-	.priority	=	1,
-};
-
 static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n)
 {
 	int h;
@@ -984,6 +1061,27 @@ static struct pernet_operations vti6_net_ops = {
 	.size = sizeof(struct vti6_net),
 };
 
+static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
+	.handler	=	vti6_rcv,
+	.cb_handler	=	vti6_rcv_cb,
+	.err_handler	=	vti6_err,
+	.priority	=	100,
+};
+
+static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
+	.handler	=	vti6_rcv,
+	.cb_handler	=	vti6_rcv_cb,
+	.err_handler	=	vti6_err,
+	.priority	=	100,
+};
+
+static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
+	.handler	=	vti6_rcv,
+	.cb_handler	=	vti6_rcv_cb,
+	.err_handler	=	vti6_err,
+	.priority	=	100,
+};
+
 /**
  * vti6_tunnel_init - register protocol and reserve needed resources
  *
@@ -997,11 +1095,33 @@ static int __init vti6_tunnel_init(void)
 	if (err < 0)
 		goto out_pernet;
 
-	err = xfrm6_mode_tunnel_input_register(&vti6_handler);
+	err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
 	if (err < 0) {
-		pr_err("%s: can't register vti6\n", __func__);
+		unregister_pernet_device(&vti6_net_ops);
+		pr_err("%s: can't register vti6 protocol\n", __func__);
+
 		goto out;
 	}
+
+	err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
+	if (err < 0) {
+		xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
+		unregister_pernet_device(&vti6_net_ops);
+		pr_err("%s: can't register vti6 protocol\n", __func__);
+
+		goto out;
+	}
+
+	err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
+	if (err < 0) {
+		xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
+		xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
+		unregister_pernet_device(&vti6_net_ops);
+		pr_err("%s: can't register vti6 protocol\n", __func__);
+
+		goto out;
+	}
+
 	err = rtnl_link_register(&vti6_link_ops);
 	if (err < 0)
 		goto rtnl_link_failed;
@@ -1009,7 +1129,9 @@ static int __init vti6_tunnel_init(void)
 	return 0;
 
 rtnl_link_failed:
-	xfrm6_mode_tunnel_input_deregister(&vti6_handler);
+	xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
+	xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
+	xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
 out:
 	unregister_pernet_device(&vti6_net_ops);
 out_pernet:
@@ -1022,8 +1144,12 @@ out_pernet:
 static void __exit vti6_tunnel_cleanup(void)
 {
 	rtnl_link_unregister(&vti6_link_ops);
-	if (xfrm6_mode_tunnel_input_deregister(&vti6_handler))
-		pr_info("%s: can't deregister vti6\n", __func__);
+	if (xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP))
+		pr_info("%s: can't deregister protocol\n", __func__);
+	if (xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH))
+		pr_info("%s: can't deregister protocol\n", __func__);
+	if (xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP))
+		pr_info("%s: can't deregister protocol\n", __func__);
 
 	unregister_pernet_device(&vti6_net_ops);
 }