openvswitch: Add support for Geneve tunneling.

The Openvswitch implementation is completely agnostic to the options
that are in use and can handle newly defined options without
further work. It does this by simply matching on a byte array
of options and allowing userspace to setup flows on this array.

Signed-off-by: Jesse Gross <jesse@nicira.com>
Singed-off-by: Ansis Atteka <aatteka@nicira.com>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 236 insertions, 0 deletions

diff --git a/net/openvswitch/vport-geneve.c b/net/openvswitch/vport-geneve.c
new file mode 100644
index 0000000..5572d48
--- /dev/null
+++ b/net/openvswitch/vport-geneve.c
@@ -0,0 +1,236 @@
+/*
+ * Copyright (c) 2014 Nicira, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/version.h>
+
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/net.h>
+#include <linux/rculist.h>
+#include <linux/udp.h>
+#include <linux/if_vlan.h>
+
+#include <net/geneve.h>
+#include <net/icmp.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <net/udp.h>
+#include <net/xfrm.h>
+
+#include "datapath.h"
+#include "vport.h"
+
+/**
+ * struct geneve_port - Keeps track of open UDP ports
+ * @sock: The socket created for this port number.
+ * @name: vport name.
+ */
+struct geneve_port {
+	struct geneve_sock *gs;
+	char name[IFNAMSIZ];
+};
+
+static LIST_HEAD(geneve_ports);
+
+static inline struct geneve_port *geneve_vport(const struct vport *vport)
+{
+	return vport_priv(vport);
+}
+
+static inline struct genevehdr *geneve_hdr(const struct sk_buff *skb)
+{
+	return (struct genevehdr *)(udp_hdr(skb) + 1);
+}
+
+/* Convert 64 bit tunnel ID to 24 bit VNI. */
+static void tunnel_id_to_vni(__be64 tun_id, __u8 *vni)
+{
+#ifdef __BIG_ENDIAN
+	vni[0] = (__force __u8)(tun_id >> 16);
+	vni[1] = (__force __u8)(tun_id >> 8);
+	vni[2] = (__force __u8)tun_id;
+#else
+	vni[0] = (__force __u8)((__force u64)tun_id >> 40);
+	vni[1] = (__force __u8)((__force u64)tun_id >> 48);
+	vni[2] = (__force __u8)((__force u64)tun_id >> 56);
+#endif
+}
+
+/* Convert 24 bit VNI to 64 bit tunnel ID. */
+static __be64 vni_to_tunnel_id(__u8 *vni)
+{
+#ifdef __BIG_ENDIAN
+	return (vni[0] << 16) | (vni[1] << 8) | vni[2];
+#else
+	return (__force __be64)(((__force u64)vni[0] << 40) |
+				((__force u64)vni[1] << 48) |
+				((__force u64)vni[2] << 56));
+#endif
+}
+
+static void geneve_rcv(struct geneve_sock *gs, struct sk_buff *skb)
+{
+	struct vport *vport = gs->rcv_data;
+	struct genevehdr *geneveh = geneve_hdr(skb);
+	int opts_len;
+	struct ovs_tunnel_info tun_info;
+	__be64 key;
+	__be16 flags;
+
+	opts_len = geneveh->opt_len * 4;
+
+	flags = TUNNEL_KEY | TUNNEL_OPTIONS_PRESENT |
+		(udp_hdr(skb)->check != 0 ? TUNNEL_CSUM : 0) |
+		(geneveh->oam ? TUNNEL_OAM : 0) |
+		(geneveh->critical ? TUNNEL_CRIT_OPT : 0);
+
+	key = vni_to_tunnel_id(geneveh->vni);
+
+	ovs_flow_tun_info_init(&tun_info, ip_hdr(skb), key, flags,
+			       geneveh->options, opts_len);
+
+	ovs_vport_receive(vport, skb, &tun_info);
+}
+
+static int geneve_get_options(const struct vport *vport,
+			      struct sk_buff *skb)
+{
+	struct geneve_port *geneve_port = geneve_vport(vport);
+	__be16 sport;
+
+	sport = ntohs(inet_sk(geneve_port->gs->sock->sk)->inet_sport);
+	if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, sport))
+		return -EMSGSIZE;
+	return 0;
+}
+
+static void geneve_tnl_destroy(struct vport *vport)
+{
+	struct geneve_port *geneve_port = geneve_vport(vport);
+
+	geneve_sock_release(geneve_port->gs);
+
+	ovs_vport_deferred_free(vport);
+}
+
+static struct vport *geneve_tnl_create(const struct vport_parms *parms)
+{
+	struct net *net = ovs_dp_get_net(parms->dp);
+	struct nlattr *options = parms->options;
+	struct geneve_port *geneve_port;
+	struct geneve_sock *gs;
+	struct vport *vport;
+	struct nlattr *a;
+	int err;
+	u16 dst_port;
+
+	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 geneve_port),
+				&ovs_geneve_vport_ops, parms);
+	if (IS_ERR(vport))
+		return vport;
+
+	geneve_port = geneve_vport(vport);
+	strncpy(geneve_port->name, parms->name, IFNAMSIZ);
+
+	gs = geneve_sock_add(net, htons(dst_port), geneve_rcv, vport, true, 0);
+	if (IS_ERR(gs)) {
+		ovs_vport_free(vport);
+		return (void *)gs;
+	}
+	geneve_port->gs = gs;
+
+	return vport;
+error:
+	return ERR_PTR(err);
+}
+
+static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
+{
+	struct ovs_key_ipv4_tunnel *tun_key;
+	struct ovs_tunnel_info *tun_info;
+	struct net *net = ovs_dp_get_net(vport->dp);
+	struct geneve_port *geneve_port = geneve_vport(vport);
+	__be16 dport = inet_sk(geneve_port->gs->sock->sk)->inet_sport;
+	__be16 sport;
+	struct rtable *rt;
+	struct flowi4 fl;
+	u8 vni[3];
+	__be16 df;
+	int err;
+
+	tun_info = OVS_CB(skb)->egress_tun_info;
+	if (unlikely(!tun_info)) {
+		err = -EINVAL;
+		goto error;
+	}
+
+	tun_key = &tun_info->tunnel;
+
+	/* Route lookup */
+	memset(&fl, 0, sizeof(fl));
+	fl.daddr = tun_key->ipv4_dst;
+	fl.saddr = tun_key->ipv4_src;
+	fl.flowi4_tos = RT_TOS(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 = tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
+	sport = udp_flow_src_port(net, skb, 1, USHRT_MAX, true);
+	tunnel_id_to_vni(tun_key->tun_id, vni);
+	skb->ignore_df = 1;
+
+	err = geneve_xmit_skb(geneve_port->gs, rt, skb, fl.saddr,
+			      tun_key->ipv4_dst, tun_key->ipv4_tos,
+			      tun_key->ipv4_ttl, df, sport, dport,
+			      tun_key->tun_flags, vni,
+			      tun_info->options_len, (u8 *)tun_info->options,
+			      false);
+	if (err < 0)
+		ip_rt_put(rt);
+error:
+	return err;
+}
+
+static const char *geneve_get_name(const struct vport *vport)
+{
+	struct geneve_port *geneve_port = geneve_vport(vport);
+
+	return geneve_port->name;
+}
+
+const struct vport_ops ovs_geneve_vport_ops = {
+	.type		= OVS_VPORT_TYPE_GENEVE,
+	.create		= geneve_tnl_create,
+	.destroy	= geneve_tnl_destroy,
+	.get_name	= geneve_get_name,
+	.get_options	= geneve_get_options,
+	.send		= geneve_tnl_send,
+};