diff options
author | John W. Linville <linville@tuxdriver.com> | 2015-05-13 16:57:30 (GMT) |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-05-13 19:59:13 (GMT) |
commit | 2d07dc79fe04a43d82a346ced6bbf07bdb523f1b (patch) | |
tree | 2c6eaa5b8f0cc9931d3db53d60ef2fae12349a02 | |
parent | d37d29c30509854d15401277f39aab0336525f27 (diff) | |
download | linux-2d07dc79fe04a43d82a346ced6bbf07bdb523f1b.tar.xz |
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: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | drivers/net/Kconfig | 14 | ||||
-rw-r--r-- | drivers/net/Makefile | 1 | ||||
-rw-r--r-- | drivers/net/geneve.c | 503 | ||||
-rw-r--r-- | include/uapi/linux/if_link.h | 9 |
4 files changed, 527 insertions, 0 deletions
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index df51d60..019fcef 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -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--- diff --git a/drivers/net/Makefile b/drivers/net/Makefile index e25fdd7..c12cb22 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -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 # diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c new file mode 100644 index 0000000..b7eafa4 --- /dev/null +++ b/drivers/net/geneve.c @@ -0,0 +1,503 @@ +/* + * 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"); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 6d6e502..afccc93 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -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 { |