openvswitch: Add vxlan tunneling support.

Following patch adds vxlan vport type for openvswitch using
vxlan api. So now there is vxlan dependency for openvswitch.

CC: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 225 insertions, 0 deletions

diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig
index 27ee56b688a3..bed30e69baa7 100644
--- a/net/openvswitch/Kconfig
+++ b/net/openvswitch/Kconfig
@@ -40,3 +40,16 @@ config OPENVSWITCH_GRE
           Say N to exclude this support and reduce the binary size.
 
           If unsure, say Y.
+
+config OPENVSWITCH_VXLAN
+        bool "Open vSwitch VXLAN tunneling support"
+        depends on INET
+        depends on OPENVSWITCH
+        depends on VXLAN && !(OPENVSWITCH=y && VXLAN=m)
+        default y
+        ---help---
+          If you say Y here, then the Open vSwitch will be able create vxlan vport.
+
+          Say N to exclude this support and reduce the binary size.
+
+          If unsure, say Y.
diff --git a/net/openvswitch/Makefile b/net/openvswitch/Makefile
index 01bddb2991e3..82e4ee54a44b 100644
--- a/net/openvswitch/Makefile
+++ b/net/openvswitch/Makefile
@@ -13,3 +13,7 @@ openvswitch-y := \
         vport-gre.o \
         vport-internal_dev.o \
         vport-netdev.o
+
+ifneq ($(CONFIG_OPENVSWITCH_VXLAN),)
+openvswitch-y += vport-vxlan.o
+endif
diff --git a/net/openvswitch/vport-vxlan.c b/net/openvswitch/vport-vxlan.c
new file mode 100644
index 000000000000..36848bd54a77
--- /dev/null
+++ b/net/openvswitch/vport-vxlan.c
@@ -0,0 +1,204 @@
+/*
+ * Copyright (c) 2013 Nicira, Inc.
+ * Copyright (c) 2013 Cisco Systems, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/net.h>
+#include <linux/rculist.h>
+#include <linux/udp.h>
+
+#include <net/icmp.h>
+#include <net/ip.h>
+#include <net/udp.h>
+#include <net/ip_tunnels.h>
+#include <net/udp.h>
+#include <net/rtnetlink.h>
+#include <net/route.h>
+#include <net/dsfield.h>
+#include <net/inet_ecn.h>
+#include <net/net_namespace.h>
+#include <net/netns/generic.h>
+#include <net/vxlan.h>
+
+#include "datapath.h"
+#include "vport.h"
+
+/**
+ * struct vxlan_port - Keeps track of open UDP ports
+ * @vs: vxlan_sock created for the port.
+ * @name: vport name.
+ */
+struct vxlan_port {
+        struct vxlan_sock *vs;
+        char name[IFNAMSIZ];
+};
+
+static inline struct vxlan_port *vxlan_vport(const struct vport *vport)
+{
+        return vport_priv(vport);
+}
+
+/* Called with rcu_read_lock and BH disabled. */
+static void vxlan_rcv(struct vxlan_sock *vs, struct sk_buff *skb, __be32 vx_vni)
+{
+        struct ovs_key_ipv4_tunnel tun_key;
+        struct vport *vport = vs->data;
+        struct iphdr *iph;
+        __be64 key;
+
+        /* Save outer tunnel values */
+        iph = ip_hdr(skb);
+        key = cpu_to_be64(ntohl(vx_vni) >> 8);
+        ovs_flow_tun_key_init(&tun_key, iph, key, TUNNEL_KEY);
+
+        ovs_vport_receive(vport, skb, &tun_key);
+}
+
+static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
+{
+        struct vxlan_port *vxlan_port = vxlan_vport(vport);
+        __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
+
+        if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
+                return -EMSGSIZE;
+        return 0;
+}
+
+static void vxlan_tnl_destroy(struct vport *vport)
+{
+        struct vxlan_port *vxlan_port = vxlan_vport(vport);
+
+        vxlan_sock_release(vxlan_port->vs);
+
+        ovs_vport_deferred_free(vport);
+}
+
+static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
+{
+        struct net *net = ovs_dp_get_net(parms->dp);
+        struct nlattr *options = parms->options;
+        struct vxlan_port *vxlan_port;
+        struct vxlan_sock *vs;
+        struct vport *vport;
+        struct nlattr *a;
+        u16 dst_port;
+        int err;
+
+        if (!options) {
+                err = -EINVAL;
+                goto error;
+        }
+        a = nla_find_nested(options, OVS_TUNNEL_ATTR_DST_PORT);
+        if (a && nla_len(a) == sizeof(u16)) {
+                dst_port = nla_get_u16(a);
+        } else {
+                /* Require destination port from userspace. */
+                err = -EINVAL;
+                goto error;
+        }
+
+        vport = ovs_vport_alloc(sizeof(struct vxlan_port),
+                                &ovs_vxlan_vport_ops, parms);
+        if (IS_ERR(vport))
+                return vport;
+
+        vxlan_port = vxlan_vport(vport);
+        strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
+
+        vs = vxlan_sock_add(net, htons(dst_port), vxlan_rcv, vport, true);
+        if (IS_ERR(vs)) {
+                ovs_vport_free(vport);
+                return (void *)vs;
+        }
+        vxlan_port->vs = vs;
+
+        return vport;
+
+error:
+        return ERR_PTR(err);
+}
+
+static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
+{
+        struct net *net = ovs_dp_get_net(vport->dp);
+        struct vxlan_port *vxlan_port = vxlan_vport(vport);
+        __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
+        struct rtable *rt;
+        struct flowi4 fl;
+        __be16 src_port;
+        int port_min;
+        int port_max;
+        __be16 df;
+        int err;
+
+        if (unlikely(!OVS_CB(skb)->tun_key)) {
+                err = -EINVAL;
+                goto error;
+        }
+
+        /* Route lookup */
+        memset(&fl, 0, sizeof(fl));
+        fl.daddr = OVS_CB(skb)->tun_key->ipv4_dst;
+        fl.saddr = OVS_CB(skb)->tun_key->ipv4_src;
+        fl.flowi4_tos = RT_TOS(OVS_CB(skb)->tun_key->ipv4_tos);
+        fl.flowi4_mark = skb->mark;
+        fl.flowi4_proto = IPPROTO_UDP;
+
+        rt = ip_route_output_key(net, &fl);
+        if (IS_ERR(rt)) {
+                err = PTR_ERR(rt);
+                goto error;
+        }
+
+        df = OVS_CB(skb)->tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
+                htons(IP_DF) : 0;
+
+        skb->local_df = 1;
+
+        inet_get_local_port_range(&port_min, &port_max);
+        src_port = vxlan_src_port(port_min, port_max, skb);
+
+        err = vxlan_xmit_skb(net, vxlan_port->vs, rt, skb,
+                             fl.saddr, OVS_CB(skb)->tun_key->ipv4_dst,
+                             OVS_CB(skb)->tun_key->ipv4_tos,
+                             OVS_CB(skb)->tun_key->ipv4_ttl, df,
+                             src_port, dst_port,
+                             htonl(be64_to_cpu(OVS_CB(skb)->tun_key->tun_id) << 8));
+        if (err < 0)
+                ip_rt_put(rt);
+error:
+        return err;
+}
+
+static const char *vxlan_get_name(const struct vport *vport)
+{
+        struct vxlan_port *vxlan_port = vxlan_vport(vport);
+        return vxlan_port->name;
+}
+
+const struct vport_ops ovs_vxlan_vport_ops = {
+        .type           = OVS_VPORT_TYPE_VXLAN,
+        .create         = vxlan_tnl_create,
+        .destroy        = vxlan_tnl_destroy,
+        .get_name       = vxlan_get_name,
+        .get_options    = vxlan_get_options,
+        .send           = vxlan_tnl_send,
+};
diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c
index d4c7fa04ce08..d69e0c06dfde 100644
--- a/net/openvswitch/vport.c
+++ b/net/openvswitch/vport.c
@@ -42,6 +42,9 @@ static const struct vport_ops *vport_ops_list[] = {
 #ifdef CONFIG_OPENVSWITCH_GRE
         &ovs_gre_vport_ops,
 #endif
+#ifdef CONFIG_OPENVSWITCH_VXLAN
+        &ovs_vxlan_vport_ops,
+#endif
 };
 
 /* Protected by RCU read lock for reading, ovs_mutex for writing. */
diff --git a/net/openvswitch/vport.h b/net/openvswitch/vport.h
index 376045c42f8b..1a9fbcec6e1b 100644
--- a/net/openvswitch/vport.h
+++ b/net/openvswitch/vport.h
@@ -199,6 +199,7 @@ void ovs_vport_record_error(struct vport *, enum vport_err_type err_type);
 extern const struct vport_ops ovs_netdev_vport_ops;
 extern const struct vport_ops ovs_internal_vport_ops;
 extern const struct vport_ops ovs_gre_vport_ops;
+extern const struct vport_ops ovs_vxlan_vport_ops;
 
 static inline void ovs_skb_postpush_rcsum(struct sk_buff *skb,
                                       const void *start, unsigned int len)