Commit 2d07dc79 authored by John W. Linville's avatar John W. Linville Committed by David S. Miller
Browse files

geneve: add initial netdev driver for GENEVE tunnels



This is an initial implementation of a netdev driver for GENEVE
tunnels.  This implementation uses a fixed UDP port, and only supports
point-to-point links with specific partner endpoints.  Only IPv4
links are supported at this time.
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d37d29c3
......@@ -179,6 +179,20 @@ config VXLAN
To compile this driver as a module, choose M here: the module
will be called vxlan.
config GENEVE
tristate "Generic Network Virtualization Encapsulation netdev"
depends on INET && GENEVE_CORE
select NET_IP_TUNNEL
---help---
This allows one to create geneve virtual interfaces that provide
Layer 2 Networks over Layer 3 Networks. GENEVE is often used
to tunnel virtual network infrastructure in virtualized environments.
For more information see:
http://tools.ietf.org/html/draft-gross-geneve-02
To compile this driver as a module, choose M here: the module
will be called geneve.
config NETCONSOLE
tristate "Network console logging support"
---help---
......
......@@ -23,6 +23,7 @@ obj-$(CONFIG_TUN) += tun.o
obj-$(CONFIG_VETH) += veth.o
obj-$(CONFIG_VIRTIO_NET) += virtio_net.o
obj-$(CONFIG_VXLAN) += vxlan.o
obj-$(CONFIG_GENEVE) += geneve.o
obj-$(CONFIG_NLMON) += nlmon.o
#
......
/*
* GENEVE: Generic Network Virtualization Encapsulation
*
* Copyright (c) 2015 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/hash.h>
#include <net/rtnetlink.h>
#include <net/geneve.h>
#define GENEVE_NETDEV_VER "0.6"
#define GENEVE_UDP_PORT 6081
#define GENEVE_N_VID (1u << 24)
#define GENEVE_VID_MASK (GENEVE_N_VID - 1)
#define VNI_HASH_BITS 10
#define VNI_HASH_SIZE (1<<VNI_HASH_BITS)
static bool log_ecn_error = true;
module_param(log_ecn_error, bool, 0644);
MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
/* per-network namespace private data for this module */
struct geneve_net {
struct list_head geneve_list;
struct hlist_head vni_list[VNI_HASH_SIZE];
};
/* Pseudo network device */
struct geneve_dev {
struct hlist_node hlist; /* vni hash table */
struct net *net; /* netns for packet i/o */
struct net_device *dev; /* netdev for geneve tunnel */
struct geneve_sock *sock; /* socket used for geneve tunnel */
u8 vni[3]; /* virtual network ID for tunnel */
struct sockaddr_in remote; /* IPv4 address for link partner */
struct list_head next; /* geneve's per namespace list */
};
static int geneve_net_id;
static inline __u32 geneve_net_vni_hash(u8 vni[3])
{
__u32 vnid;
vnid = (vni[0] << 16) | (vni[1] << 8) | vni[2];
return hash_32(vnid, VNI_HASH_BITS);
}
/* geneve receive/decap routine */
static void geneve_rx(struct geneve_sock *gs, struct sk_buff *skb)
{
struct genevehdr *gnvh = geneve_hdr(skb);
struct geneve_dev *dummy, *geneve = NULL;
struct geneve_net *gn;
struct iphdr *iph = NULL;
struct pcpu_sw_netstats *stats;
struct hlist_head *vni_list_head;
int err = 0;
__u32 hash;
iph = ip_hdr(skb); /* Still outer IP header... */
gn = gs->rcv_data;
/* Find the device for this VNI */
hash = geneve_net_vni_hash(gnvh->vni);
vni_list_head = &gn->vni_list[hash];
hlist_for_each_entry_rcu(dummy, vni_list_head, hlist) {
if (!memcmp(gnvh->vni, dummy->vni, sizeof(dummy->vni)) &&
iph->saddr == dummy->remote.sin_addr.s_addr) {
geneve = dummy;
break;
}
}
if (!geneve)
goto drop;
/* Drop packets w/ critical options,
* since we don't support any...
*/
if (gnvh->critical)
goto drop;
skb_reset_mac_header(skb);
skb_scrub_packet(skb, !net_eq(geneve->net, dev_net(geneve->dev)));
skb->protocol = eth_type_trans(skb, geneve->dev);
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
/* Ignore packet loops (and multicast echo) */
if (ether_addr_equal(eth_hdr(skb)->h_source, geneve->dev->dev_addr))
goto drop;
skb_reset_network_header(skb);
iph = ip_hdr(skb); /* Now inner IP header... */
err = IP_ECN_decapsulate(iph, skb);
if (unlikely(err)) {
if (log_ecn_error)
net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
&iph->saddr, iph->tos);
if (err > 1) {
++geneve->dev->stats.rx_frame_errors;
++geneve->dev->stats.rx_errors;
goto drop;
}
}
stats = this_cpu_ptr(geneve->dev->tstats);
u64_stats_update_begin(&stats->syncp);
stats->rx_packets++;
stats->rx_bytes += skb->len;
u64_stats_update_end(&stats->syncp);
netif_rx(skb);
return;
drop:
/* Consume bad packet */
kfree_skb(skb);
}
/* Setup stats when device is created */
static int geneve_init(struct net_device *dev)
{
dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
if (!dev->tstats)
return -ENOMEM;
return 0;
}
static void geneve_uninit(struct net_device *dev)
{
free_percpu(dev->tstats);
}
static int geneve_open(struct net_device *dev)
{
struct geneve_dev *geneve = netdev_priv(dev);
struct net *net = geneve->net;
struct geneve_net *gn = net_generic(geneve->net, geneve_net_id);
struct geneve_sock *gs;
gs = geneve_sock_add(net, htons(GENEVE_UDP_PORT), geneve_rx, gn,
false, false);
if (IS_ERR(gs))
return PTR_ERR(gs);
geneve->sock = gs;
return 0;
}
static int geneve_stop(struct net_device *dev)
{
struct geneve_dev *geneve = netdev_priv(dev);
struct geneve_sock *gs = geneve->sock;
geneve_sock_release(gs);
return 0;
}
static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct geneve_dev *geneve = netdev_priv(dev);
struct geneve_sock *gs = geneve->sock;
struct rtable *rt = NULL;
const struct iphdr *iip; /* interior IP header */
struct flowi4 fl4;
int err;
__be16 sport;
__u8 tos, ttl = 0;
iip = ip_hdr(skb);
skb_reset_mac_header(skb);
/* TODO: port min/max limits should be configurable */
sport = udp_flow_src_port(dev_net(dev), skb, 0, 0, true);
memset(&fl4, 0, sizeof(fl4));
fl4.daddr = geneve->remote.sin_addr.s_addr;
rt = ip_route_output_key(geneve->net, &fl4);
if (IS_ERR(rt)) {
netdev_dbg(dev, "no route to %pI4\n", &fl4.daddr);
dev->stats.tx_carrier_errors++;
goto tx_error;
}
if (rt->dst.dev == dev) { /* is this necessary? */
netdev_dbg(dev, "circular route to %pI4\n", &fl4.daddr);
dev->stats.collisions++;
goto rt_tx_error;
}
/* TODO: tos and ttl should be configurable */
tos = ip_tunnel_ecn_encap(0, iip, skb);
if (IN_MULTICAST(ntohl(fl4.daddr)))
ttl = 1;
ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
/* no need to handle local destination and encap bypass...yet... */
err = geneve_xmit_skb(gs, rt, skb, fl4.saddr, fl4.daddr,
tos, ttl, 0, sport, htons(GENEVE_UDP_PORT), 0,
geneve->vni, 0, NULL, false,
!net_eq(geneve->net, dev_net(geneve->dev)));
if (err < 0)
ip_rt_put(rt);
iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
return NETDEV_TX_OK;
rt_tx_error:
ip_rt_put(rt);
tx_error:
dev->stats.tx_errors++;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
static const struct net_device_ops geneve_netdev_ops = {
.ndo_init = geneve_init,
.ndo_uninit = geneve_uninit,
.ndo_open = geneve_open,
.ndo_stop = geneve_stop,
.ndo_start_xmit = geneve_xmit,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_change_mtu = eth_change_mtu,
.ndo_validate_addr = eth_validate_addr,
.ndo_set_mac_address = eth_mac_addr,
};
static void geneve_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *drvinfo)
{
strlcpy(drvinfo->version, GENEVE_NETDEV_VER, sizeof(drvinfo->version));
strlcpy(drvinfo->driver, "geneve", sizeof(drvinfo->driver));
}
static const struct ethtool_ops geneve_ethtool_ops = {
.get_drvinfo = geneve_get_drvinfo,
.get_link = ethtool_op_get_link,
};
/* Info for udev, that this is a virtual tunnel endpoint */
static struct device_type geneve_type = {
.name = "geneve",
};
/* Initialize the device structure. */
static void geneve_setup(struct net_device *dev)
{
ether_setup(dev);
dev->netdev_ops = &geneve_netdev_ops;
dev->ethtool_ops = &geneve_ethtool_ops;
dev->destructor = free_netdev;
SET_NETDEV_DEVTYPE(dev, &geneve_type);
dev->tx_queue_len = 0;
dev->features |= NETIF_F_LLTX;
dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
dev->features |= NETIF_F_RXCSUM;
dev->features |= NETIF_F_GSO_SOFTWARE;
dev->vlan_features = dev->features;
dev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
dev->hw_features |= NETIF_F_GSO_SOFTWARE;
dev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
netif_keep_dst(dev);
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
}
static const struct nla_policy geneve_policy[IFLA_GENEVE_MAX + 1] = {
[IFLA_GENEVE_ID] = { .type = NLA_U32 },
[IFLA_GENEVE_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) },
};
static int geneve_validate(struct nlattr *tb[], struct nlattr *data[])
{
if (tb[IFLA_ADDRESS]) {
if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
return -EINVAL;
if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
return -EADDRNOTAVAIL;
}
if (!data)
return -EINVAL;
if (data[IFLA_GENEVE_ID]) {
__u32 vni = nla_get_u32(data[IFLA_GENEVE_ID]);
if (vni >= GENEVE_VID_MASK)
return -ERANGE;
}
return 0;
}
static int geneve_newlink(struct net *net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct geneve_net *gn = net_generic(net, geneve_net_id);
struct geneve_dev *dummy, *geneve = netdev_priv(dev);
struct hlist_head *vni_list_head;
struct sockaddr_in remote; /* IPv4 address for link partner */
__u32 vni, hash;
int err;
if (!data[IFLA_GENEVE_ID] || !data[IFLA_GENEVE_REMOTE])
return -EINVAL;
geneve->net = net;
geneve->dev = dev;
vni = nla_get_u32(data[IFLA_GENEVE_ID]);
geneve->vni[0] = (vni & 0x00ff0000) >> 16;
geneve->vni[1] = (vni & 0x0000ff00) >> 8;
geneve->vni[2] = vni & 0x000000ff;
geneve->remote.sin_addr.s_addr =
nla_get_in_addr(data[IFLA_GENEVE_REMOTE]);
if (IN_MULTICAST(ntohl(geneve->remote.sin_addr.s_addr)))
return -EINVAL;
remote = geneve->remote;
hash = geneve_net_vni_hash(geneve->vni);
vni_list_head = &gn->vni_list[hash];
hlist_for_each_entry_rcu(dummy, vni_list_head, hlist) {
if (!memcmp(geneve->vni, dummy->vni, sizeof(dummy->vni)) &&
!memcmp(&remote, &dummy->remote, sizeof(dummy->remote)))
return -EBUSY;
}
if (tb[IFLA_ADDRESS] == NULL)
eth_hw_addr_random(dev);
err = register_netdevice(dev);
if (err)
return err;
list_add(&geneve->next, &gn->geneve_list);
hlist_add_head_rcu(&geneve->hlist, &gn->vni_list[hash]);
return 0;
}
static void geneve_dellink(struct net_device *dev, struct list_head *head)
{
struct geneve_dev *geneve = netdev_priv(dev);
if (!hlist_unhashed(&geneve->hlist))
hlist_del_rcu(&geneve->hlist);
list_del(&geneve->next);
unregister_netdevice_queue(dev, head);
}
static size_t geneve_get_size(const struct net_device *dev)
{
return nla_total_size(sizeof(__u32)) + /* IFLA_GENEVE_ID */
nla_total_size(sizeof(struct in_addr)) + /* IFLA_GENEVE_REMOTE */
0;
}
static int geneve_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct geneve_dev *geneve = netdev_priv(dev);
__u32 vni;
vni = (geneve->vni[0] << 16) | (geneve->vni[1] << 8) | geneve->vni[2];
if (nla_put_u32(skb, IFLA_GENEVE_ID, vni))
goto nla_put_failure;
if (nla_put_in_addr(skb, IFLA_GENEVE_REMOTE,
geneve->remote.sin_addr.s_addr))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static struct rtnl_link_ops geneve_link_ops __read_mostly = {
.kind = "geneve",
.maxtype = IFLA_GENEVE_MAX,
.policy = geneve_policy,
.priv_size = sizeof(struct geneve_dev),
.setup = geneve_setup,
.validate = geneve_validate,
.newlink = geneve_newlink,
.dellink = geneve_dellink,
.get_size = geneve_get_size,
.fill_info = geneve_fill_info,
};
static __net_init int geneve_init_net(struct net *net)
{
struct geneve_net *gn = net_generic(net, geneve_net_id);
unsigned int h;
INIT_LIST_HEAD(&gn->geneve_list);
for (h = 0; h < VNI_HASH_SIZE; ++h)
INIT_HLIST_HEAD(&gn->vni_list[h]);
return 0;
}
static void __net_exit geneve_exit_net(struct net *net)
{
struct geneve_net *gn = net_generic(net, geneve_net_id);
struct geneve_dev *geneve, *next;
struct net_device *dev, *aux;
LIST_HEAD(list);
rtnl_lock();
/* gather any geneve devices that were moved into this ns */
for_each_netdev_safe(net, dev, aux)
if (dev->rtnl_link_ops == &geneve_link_ops)
unregister_netdevice_queue(dev, &list);
/* now gather any other geneve devices that were created in this ns */
list_for_each_entry_safe(geneve, next, &gn->geneve_list, next) {
/* If geneve->dev is in the same netns, it was already added
* to the list by the previous loop.
*/
if (!net_eq(dev_net(geneve->dev), net))
unregister_netdevice_queue(geneve->dev, &list);
}
/* unregister the devices gathered above */
unregister_netdevice_many(&list);
rtnl_unlock();
}
static struct pernet_operations geneve_net_ops = {
.init = geneve_init_net,
.exit = geneve_exit_net,
.id = &geneve_net_id,
.size = sizeof(struct geneve_net),
};
static int __init geneve_init_module(void)
{
int rc;
rc = register_pernet_subsys(&geneve_net_ops);
if (rc)
goto out1;
rc = rtnl_link_register(&geneve_link_ops);
if (rc)
goto out2;
return 0;
out2:
unregister_pernet_subsys(&geneve_net_ops);
out1:
return rc;
}
late_initcall(geneve_init_module);
static void __exit geneve_cleanup_module(void)
{
rtnl_link_unregister(&geneve_link_ops);
unregister_pernet_subsys(&geneve_net_ops);
}
module_exit(geneve_cleanup_module);
MODULE_LICENSE("GPL");
MODULE_VERSION(GENEVE_NETDEV_VER);
MODULE_AUTHOR("John W. Linville <linville@tuxdriver.com>");
MODULE_DESCRIPTION("Interface driver for GENEVE encapsulated traffic");
MODULE_ALIAS_RTNL_LINK("geneve");
......@@ -390,6 +390,15 @@ struct ifla_vxlan_port_range {
__be16 high;
};
/* GENEVE section */
enum {
IFLA_GENEVE_UNSPEC,
IFLA_GENEVE_ID,
IFLA_GENEVE_REMOTE,
__IFLA_GENEVE_MAX
};
#define IFLA_GENEVE_MAX (__IFLA_GENEVE_MAX - 1)
/* Bonding section */
enum {
......
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