Merge branch 'vrf-ipv6'

David Ahern says:

====================
net: VRF support in IPv6 stack

Initial support for VRF in IPv6 stack. Makes IPv6 functionality on par
with IPv4 -- ping, tcp client/server and udp client/server all work fine.
tcpdump on vrf device and external tap (e.g., host side tap device) shows
all packets with proper addresses. IPv6 does not need the source address
operation like IPv4. Verified vti6 works properly in my setup as does use
of an IPv6 address on the VRF device.

v3
- re-based to top of net-next (updates per net namespace changes by Eric)
- fixed dst_entry typecasts as requested by Dave
- added flags to inet6_rtm_getroute (IPv6 version of deaa0a6a930e)

v2
- fixed CONFIG_IPV6 dependency as questioned by Cong
  - if IPV6 is a module, kbuild ensures VRF is a module
  - if IPV6 is disabled IPV6 functionality is compiled out of VRF module
- addressed comments from Nik over IRC
  - removed duplicate call to netif_is_l3_master in l3mdev_rt6_dst_by_oif
  - changed allocation flag from GFP_ATOMIC to GFP_KERNEL since it is init time
  - added free of rt6i_pcpu
  - check_ipv6_frame returns false only if packet is NDISC type
====================

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

6 files changed, 65 insertions, 14 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index c8380f1876f1..f0326aae7a02 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -81,6 +81,7 @@
 #include <net/ip.h>
 #include <net/netlink.h>
 #include <net/pkt_sched.h>
+#include <net/l3mdev.h>
 #include <linux/if_tunnel.h>
 #include <linux/rtnetlink.h>
 #include <linux/netconf.h>
@@ -2146,7 +2147,7 @@ addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
 		      unsigned long expires, u32 flags)
 {
 	struct fib6_config cfg = {
-		.fc_table = RT6_TABLE_PREFIX,
+		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
 		.fc_ifindex = dev->ifindex,
 		.fc_expires = expires,
@@ -2179,8 +2180,9 @@ static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
 	struct fib6_node *fn;
 	struct rt6_info *rt = NULL;
 	struct fib6_table *table;
+	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
 
-	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
+	table = fib6_get_table(dev_net(dev), tb_id);
 	if (!table)
 		return NULL;
 
@@ -2211,7 +2213,7 @@ out:
 static void addrconf_add_mroute(struct net_device *dev)
 {
 	struct fib6_config cfg = {
-		.fc_table = RT6_TABLE_LOCAL,
+		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
 		.fc_ifindex = dev->ifindex,
 		.fc_dst_len = 8,
@@ -3029,6 +3031,10 @@ static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
 {
 	struct in6_addr addr;
 
+	/* no link local addresses on L3 master devices */
+	if (netif_is_l3_master(idev->dev))
+		return;
+
 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
 
 	if (idev->addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY) {
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 6c2b2132c8d3..efb1c00f2270 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -68,6 +68,7 @@
 #include <net/xfrm.h>
 #include <net/inet_common.h>
 #include <net/dsfield.h>
+#include <net/l3mdev.h>
 
 #include <asm/uaccess.h>
 
@@ -496,6 +497,9 @@ static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
 	else if (!fl6.flowi6_oif)
 		fl6.flowi6_oif = np->ucast_oif;
 
+	if (!fl6.flowi6_oif)
+		fl6.flowi6_oif = l3mdev_master_ifindex(skb->dev);
+
 	dst = icmpv6_route_lookup(net, skb, sk, &fl6);
 	if (IS_ERR(dst))
 		goto out;
@@ -575,7 +579,7 @@ static void icmpv6_echo_reply(struct sk_buff *skb)
 	fl6.daddr = ipv6_hdr(skb)->saddr;
 	if (saddr)
 		fl6.saddr = *saddr;
-	fl6.flowi6_oif = skb->dev->ifindex;
+	fl6.flowi6_oif = l3mdev_fib_oif(skb->dev);
 	fl6.fl6_icmp_type = ICMPV6_ECHO_REPLY;
 	fl6.flowi6_mark = mark;
 	security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 7d2e0023c72d..09fddf70cca4 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -264,6 +264,7 @@ struct fib6_table *fib6_get_table(struct net *net, u32 id)
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(fib6_get_table);
 
 static void __net_init fib6_tables_init(struct net *net)
 {
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 32583b507c2e..23f97c4783bb 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -55,6 +55,7 @@
 #include <net/xfrm.h>
 #include <net/checksum.h>
 #include <linux/mroute6.h>
+#include <net/l3mdev.h>
 
 static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
@@ -885,7 +886,8 @@ static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
 #ifdef CONFIG_IPV6_SUBTREES
 	    ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
 #endif
-	    (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex)) {
+	   (!(fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) &&
+	      (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex))) {
 		dst_release(dst);
 		dst = NULL;
 	}
@@ -1037,7 +1039,7 @@ struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
 	if (final_dst)
 		fl6->daddr = *final_dst;
 	if (!fl6->flowi6_oif)
-		fl6->flowi6_oif = dst->dev->ifindex;
+		fl6->flowi6_oif = l3mdev_fib_oif(dst->dev);
 
 	return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
 }
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index b18012f9f9fc..3e0f855e1bea 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -67,6 +67,7 @@
 #include <net/flow.h>
 #include <net/ip6_checksum.h>
 #include <net/inet_common.h>
+#include <net/l3mdev.h>
 #include <linux/proc_fs.h>
 
 #include <linux/netfilter.h>
@@ -147,6 +148,7 @@ struct neigh_table nd_tbl = {
 	.gc_thresh2 =	 512,
 	.gc_thresh3 =	1024,
 };
+EXPORT_SYMBOL_GPL(nd_tbl);
 
 static void ndisc_fill_addr_option(struct sk_buff *skb, int type, void *data)
 {
@@ -441,8 +443,11 @@ static void ndisc_send_skb(struct sk_buff *skb,
 
 	if (!dst) {
 		struct flowi6 fl6;
+		int oif = l3mdev_fib_oif(skb->dev);
 
-		icmpv6_flow_init(sk, &fl6, type, saddr, daddr, skb->dev->ifindex);
+		icmpv6_flow_init(sk, &fl6, type, saddr, daddr, oif);
+		if (oif != skb->dev->ifindex)
+			fl6.flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
 		dst = icmp6_dst_alloc(skb->dev, &fl6);
 		if (IS_ERR(dst)) {
 			kfree_skb(skb);
@@ -766,7 +771,7 @@ static void ndisc_recv_ns(struct sk_buff *skb)
 
 	ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
 	if (ifp) {
-
+have_ifp:
 		if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
 			if (dad) {
 				/*
@@ -792,6 +797,18 @@ static void ndisc_recv_ns(struct sk_buff *skb)
 	} else {
 		struct net *net = dev_net(dev);
 
+		/* perhaps an address on the master device */
+		if (netif_is_l3_slave(dev)) {
+			struct net_device *mdev;
+
+			mdev = netdev_master_upper_dev_get_rcu(dev);
+			if (mdev) {
+				ifp = ipv6_get_ifaddr(net, &msg->target, mdev, 1);
+				if (ifp)
+					goto have_ifp;
+			}
+		}
+
 		idev = in6_dev_get(dev);
 		if (!idev) {
 			/* XXX: count this drop? */
@@ -1483,6 +1500,7 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
 	struct flowi6 fl6;
 	int rd_len;
 	u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
+	int oif = l3mdev_fib_oif(dev);
 	bool ret;
 
 	if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
@@ -1499,7 +1517,10 @@ void ndisc_send_redirect(struct sk_buff *skb, const struct in6_addr *target)
 	}
 
 	icmpv6_flow_init(sk, &fl6, NDISC_REDIRECT,
-			 &saddr_buf, &ipv6_hdr(skb)->saddr, dev->ifindex);
+			 &saddr_buf, &ipv6_hdr(skb)->saddr, oif);
+
+	if (oif != skb->dev->ifindex)
+		fl6.flowi6_flags |= FLOWI_FLAG_L3MDEV_SRC;
 
 	dst = ip6_route_output(net, NULL, &fl6);
 	if (dst->error) {
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index db5b54ad5912..5fc1149fe91d 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -61,6 +61,7 @@
 #include <net/nexthop.h>
 #include <net/lwtunnel.h>
 #include <net/ip_tunnels.h>
+#include <net/l3mdev.h>
 
 #include <asm/uaccess.h>
 
@@ -1044,6 +1045,9 @@ static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
 	fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 	saved_fn = fn;
 
+	if (fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF)
+		oif = 0;
+
 redo_rt6_select:
 	rt = rt6_select(fn, oif, strict);
 	if (rt->rt6i_nsiblings)
@@ -1141,7 +1145,7 @@ void ip6_route_input(struct sk_buff *skb)
 	int flags = RT6_LOOKUP_F_HAS_SADDR;
 	struct ip_tunnel_info *tun_info;
 	struct flowi6 fl6 = {
-		.flowi6_iif = skb->dev->ifindex,
+		.flowi6_iif = l3mdev_fib_oif(skb->dev),
 		.daddr = iph->daddr,
 		.saddr = iph->saddr,
 		.flowlabel = ip6_flowinfo(iph),
@@ -1165,8 +1169,13 @@ static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table
 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
 				    struct flowi6 *fl6)
 {
+	struct dst_entry *dst;
 	int flags = 0;
 
+	dst = l3mdev_rt6_dst_by_oif(net, fl6);
+	if (dst)
+		return dst;
+
 	fl6->flowi6_iif = LOOPBACK_IFINDEX;
 
 	if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr) ||
@@ -2263,7 +2272,6 @@ static struct rt6_info *rt6_add_route_info(struct net *net,
 					   unsigned int pref)
 {
 	struct fib6_config cfg = {
-		.fc_table	= RT6_TABLE_INFO,
 		.fc_metric	= IP6_RT_PRIO_USER,
 		.fc_ifindex	= ifindex,
 		.fc_dst_len	= prefixlen,
@@ -2274,6 +2282,7 @@ static struct rt6_info *rt6_add_route_info(struct net *net,
 		.fc_nlinfo.nl_net = net,
 	};
 
+	cfg.fc_table = l3mdev_fib_table_by_index(net, ifindex) ? : RT6_TABLE_INFO;
 	cfg.fc_dst = *prefix;
 	cfg.fc_gateway = *gwaddr;
 
@@ -2314,7 +2323,7 @@ struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
 				     unsigned int pref)
 {
 	struct fib6_config cfg = {
-		.fc_table	= RT6_TABLE_DFLT,
+		.fc_table	= l3mdev_fib_table(dev) ? : RT6_TABLE_DFLT,
 		.fc_metric	= IP6_RT_PRIO_USER,
 		.fc_ifindex	= dev->ifindex,
 		.fc_flags	= RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
@@ -2361,7 +2370,8 @@ static void rtmsg_to_fib6_config(struct net *net,
 {
 	memset(cfg, 0, sizeof(*cfg));
 
-	cfg->fc_table = RT6_TABLE_MAIN;
+	cfg->fc_table = l3mdev_fib_table_by_index(net, rtmsg->rtmsg_ifindex) ?
+			 : RT6_TABLE_MAIN;
 	cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
 	cfg->fc_metric = rtmsg->rtmsg_metric;
 	cfg->fc_expires = rtmsg->rtmsg_info;
@@ -2470,6 +2480,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 				    const struct in6_addr *addr,
 				    bool anycast)
 {
+	u32 tb_id;
 	struct net *net = dev_net(idev->dev);
 	struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
 					    DST_NOCOUNT);
@@ -2492,7 +2503,8 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 	rt->rt6i_gateway  = *addr;
 	rt->rt6i_dst.addr = *addr;
 	rt->rt6i_dst.plen = 128;
-	rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
+	tb_id = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL;
+	rt->rt6i_table = fib6_get_table(net, tb_id);
 	rt->dst.flags |= DST_NOCACHE;
 
 	atomic_set(&rt->dst.__refcnt, 1);
@@ -3254,6 +3266,11 @@ static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 	} else {
 		fl6.flowi6_oif = oif;
 
+		if (netif_index_is_l3_master(net, oif)) {
+			fl6.flowi6_flags = FLOWI_FLAG_L3MDEV_SRC |
+					   FLOWI_FLAG_SKIP_NH_OIF;
+		}
+
 		rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
 	}