diff options
Diffstat (limited to 'drivers/net/vxlan.c')
| -rw-r--r-- | drivers/net/vxlan.c | 1219 |
1 files changed, 1219 insertions, 0 deletions
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c new file mode 100644 index 0000000..51de9ed --- /dev/null +++ b/drivers/net/vxlan.c @@ -0,0 +1,1219 @@ +/* + * VXLAN: Virtual eXtensiable Local Area Network + * + * Copyright (c) 2012 Vyatta 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. + * + * TODO + * - use IANA UDP port number (when defined) + * - IPv6 (not in RFC) + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/rculist.h> +#include <linux/netdevice.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/udp.h> +#include <linux/igmp.h> +#include <linux/etherdevice.h> +#include <linux/if_ether.h> +#include <linux/version.h> +#include <linux/hash.h> +#include <net/ip.h> +#include <net/icmp.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> + +#define VXLAN_VERSION "0.1" + +#define VNI_HASH_BITS 10 +#define VNI_HASH_SIZE (1<<VNI_HASH_BITS) +#define FDB_HASH_BITS 8 +#define FDB_HASH_SIZE (1<<FDB_HASH_BITS) +#define FDB_AGE_DEFAULT 300 /* 5 min */ +#define FDB_AGE_INTERVAL (10 * HZ) /* rescan interval */ + +#define VXLAN_N_VID (1u << 24) +#define VXLAN_VID_MASK (VXLAN_N_VID - 1) +/* VLAN + IP header + UDP + VXLAN */ +#define VXLAN_HEADROOM (4 + 20 + 8 + 8) + +#define VXLAN_FLAGS 0x08000000 /* struct vxlanhdr.vx_flags required value. */ + +/* VXLAN protocol header */ +struct vxlanhdr { + __be32 vx_flags; + __be32 vx_vni; +}; + +/* UDP port for VXLAN traffic. */ +static unsigned int vxlan_port __read_mostly = 8472; +module_param_named(udp_port, vxlan_port, uint, 0444); +MODULE_PARM_DESC(udp_port, "Destination UDP port"); + +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-net private data for this module */ +static unsigned int vxlan_net_id; +struct vxlan_net { + struct socket *sock; /* UDP encap socket */ + struct hlist_head vni_list[VNI_HASH_SIZE]; +}; + +/* Forwarding table entry */ +struct vxlan_fdb { + struct hlist_node hlist; /* linked list of entries */ + struct rcu_head rcu; + unsigned long updated; /* jiffies */ + unsigned long used; + __be32 remote_ip; + u16 state; /* see ndm_state */ + u8 eth_addr[ETH_ALEN]; +}; + +/* Per-cpu network traffic stats */ +struct vxlan_stats { + u64 rx_packets; + u64 rx_bytes; + u64 tx_packets; + u64 tx_bytes; + struct u64_stats_sync syncp; +}; + +/* Pseudo network device */ +struct vxlan_dev { + struct hlist_node hlist; + struct net_device *dev; + struct vxlan_stats __percpu *stats; + __u32 vni; /* virtual network id */ + __be32 gaddr; /* multicast group */ + __be32 saddr; /* source address */ + unsigned int link; /* link to multicast over */ + __u8 tos; /* TOS override */ + __u8 ttl; + bool learn; + + unsigned long age_interval; + struct timer_list age_timer; + spinlock_t hash_lock; + unsigned int addrcnt; + unsigned int addrmax; + unsigned int addrexceeded; + + struct hlist_head fdb_head[FDB_HASH_SIZE]; +}; + +/* salt for hash table */ +static u32 vxlan_salt __read_mostly; + +static inline struct hlist_head *vni_head(struct net *net, u32 id) +{ + struct vxlan_net *vn = net_generic(net, vxlan_net_id); + + return &vn->vni_list[hash_32(id, VNI_HASH_BITS)]; +} + +/* Look up VNI in a per net namespace table */ +static struct vxlan_dev *vxlan_find_vni(struct net *net, u32 id) +{ + struct vxlan_dev *vxlan; + struct hlist_node *node; + + hlist_for_each_entry_rcu(vxlan, node, vni_head(net, id), hlist) { + if (vxlan->vni == id) + return vxlan; + } + + return NULL; +} + +/* Fill in neighbour message in skbuff. */ +static int vxlan_fdb_info(struct sk_buff *skb, struct vxlan_dev *vxlan, + const struct vxlan_fdb *fdb, + u32 portid, u32 seq, int type, unsigned int flags) +{ + unsigned long now = jiffies; + struct nda_cacheinfo ci; + struct nlmsghdr *nlh; + struct ndmsg *ndm; + + nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags); + if (nlh == NULL) + return -EMSGSIZE; + + ndm = nlmsg_data(nlh); + memset(ndm, 0, sizeof(*ndm)); + ndm->ndm_family = AF_BRIDGE; + ndm->ndm_state = fdb->state; + ndm->ndm_ifindex = vxlan->dev->ifindex; + ndm->ndm_flags = NTF_SELF; + ndm->ndm_type = NDA_DST; + + if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->eth_addr)) + goto nla_put_failure; + + if (nla_put_be32(skb, NDA_DST, fdb->remote_ip)) + goto nla_put_failure; + + ci.ndm_used = jiffies_to_clock_t(now - fdb->used); + ci.ndm_confirmed = 0; + ci.ndm_updated = jiffies_to_clock_t(now - fdb->updated); + ci.ndm_refcnt = 0; + + if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci)) + goto nla_put_failure; + + return nlmsg_end(skb, nlh); + +nla_put_failure: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +static inline size_t vxlan_nlmsg_size(void) +{ + return NLMSG_ALIGN(sizeof(struct ndmsg)) + + nla_total_size(ETH_ALEN) /* NDA_LLADDR */ + + nla_total_size(sizeof(__be32)) /* NDA_DST */ + + nla_total_size(sizeof(struct nda_cacheinfo)); +} + +static void vxlan_fdb_notify(struct vxlan_dev *vxlan, + const struct vxlan_fdb *fdb, int type) +{ + struct net *net = dev_net(vxlan->dev); + struct sk_buff *skb; + int err = -ENOBUFS; + + skb = nlmsg_new(vxlan_nlmsg_size(), GFP_ATOMIC); + if (skb == NULL) + goto errout; + + err = vxlan_fdb_info(skb, vxlan, fdb, 0, 0, type, 0); + if (err < 0) { + /* -EMSGSIZE implies BUG in vxlan_nlmsg_size() */ + WARN_ON(err == -EMSGSIZE); + kfree_skb(skb); + goto errout; + } + + rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC); + return; +errout: + if (err < 0) + rtnl_set_sk_err(net, RTNLGRP_NEIGH, err); +} + +/* Hash Ethernet address */ +static u32 eth_hash(const unsigned char *addr) +{ + u64 value = get_unaligned((u64 *)addr); + + /* only want 6 bytes */ +#ifdef __BIG_ENDIAN + value <<= 16; +#else + value >>= 16; +#endif + return hash_64(value, FDB_HASH_BITS); +} + +/* Hash chain to use given mac address */ +static inline struct hlist_head *vxlan_fdb_head(struct vxlan_dev *vxlan, + const u8 *mac) +{ + return &vxlan->fdb_head[eth_hash(mac)]; +} + +/* Look up Ethernet address in forwarding table */ +static struct vxlan_fdb *vxlan_find_mac(struct vxlan_dev *vxlan, + const u8 *mac) + +{ + struct hlist_head *head = vxlan_fdb_head(vxlan, mac); + struct vxlan_fdb *f; + struct hlist_node *node; + + hlist_for_each_entry_rcu(f, node, head, hlist) { + if (compare_ether_addr(mac, f->eth_addr) == 0) + return f; + } + + return NULL; +} + +/* Add new entry to forwarding table -- assumes lock held */ +static int vxlan_fdb_create(struct vxlan_dev *vxlan, + const u8 *mac, __be32 ip, + __u16 state, __u16 flags) +{ + struct vxlan_fdb *f; + int notify = 0; + + f = vxlan_find_mac(vxlan, mac); + if (f) { + if (flags & NLM_F_EXCL) { + netdev_dbg(vxlan->dev, + "lost race to create %pM\n", mac); + return -EEXIST; + } + if (f->state != state) { + f->state = state; + f->updated = jiffies; + notify = 1; + } + } else { + if (!(flags & NLM_F_CREATE)) + return -ENOENT; + + if (vxlan->addrmax && vxlan->addrcnt >= vxlan->addrmax) + return -ENOSPC; + + netdev_dbg(vxlan->dev, "add %pM -> %pI4\n", mac, &ip); + f = kmalloc(sizeof(*f), GFP_ATOMIC); + if (!f) + return -ENOMEM; + + notify = 1; + f->remote_ip = ip; + f->state = state; + f->updated = f->used = jiffies; + memcpy(f->eth_addr, mac, ETH_ALEN); + + ++vxlan->addrcnt; + hlist_add_head_rcu(&f->hlist, + vxlan_fdb_head(vxlan, mac)); + } + + if (notify) + vxlan_fdb_notify(vxlan, f, RTM_NEWNEIGH); + + return 0; +} + +static void vxlan_fdb_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f) +{ + netdev_dbg(vxlan->dev, + "delete %pM\n", f->eth_addr); + + --vxlan->addrcnt; + vxlan_fdb_notify(vxlan, f, RTM_DELNEIGH); + + hlist_del_rcu(&f->hlist); + kfree_rcu(f, rcu); +} + +/* Add static entry (via netlink) */ +static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[], + struct net_device *dev, + const unsigned char *addr, u16 flags) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + __be32 ip; + int err; + + if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_REACHABLE))) { + pr_info("RTM_NEWNEIGH with invalid state %#x\n", + ndm->ndm_state); + return -EINVAL; + } + + if (tb[NDA_DST] == NULL) + return -EINVAL; + + if (nla_len(tb[NDA_DST]) != sizeof(__be32)) + return -EAFNOSUPPORT; + + ip = nla_get_be32(tb[NDA_DST]); + + spin_lock_bh(&vxlan->hash_lock); + err = vxlan_fdb_create(vxlan, addr, ip, ndm->ndm_state, flags); + spin_unlock_bh(&vxlan->hash_lock); + + return err; +} + +/* Delete entry (via netlink) */ +static int vxlan_fdb_delete(struct ndmsg *ndm, struct net_device *dev, + const unsigned char *addr) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_fdb *f; + int err = -ENOENT; + + spin_lock_bh(&vxlan->hash_lock); + f = vxlan_find_mac(vxlan, addr); + if (f) { + vxlan_fdb_destroy(vxlan, f); + err = 0; + } + spin_unlock_bh(&vxlan->hash_lock); + + return err; +} + +/* Dump forwarding table */ +static int vxlan_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb, + struct net_device *dev, int idx) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + unsigned int h; + + for (h = 0; h < FDB_HASH_SIZE; ++h) { + struct vxlan_fdb *f; + struct hlist_node *n; + int err; + + hlist_for_each_entry_rcu(f, n, &vxlan->fdb_head[h], hlist) { + if (idx < cb->args[0]) + goto skip; + + err = vxlan_fdb_info(skb, vxlan, f, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, + RTM_NEWNEIGH, + NLM_F_MULTI); + if (err < 0) + break; +skip: + ++idx; + } + } + + return idx; +} + +/* Watch incoming packets to learn mapping between Ethernet address + * and Tunnel endpoint. + */ +static void vxlan_snoop(struct net_device *dev, + __be32 src_ip, const u8 *src_mac) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_fdb *f; + int err; + + f = vxlan_find_mac(vxlan, src_mac); + if (likely(f)) { + f->used = jiffies; + if (likely(f->remote_ip == src_ip)) + return; + + if (net_ratelimit()) + netdev_info(dev, + "%pM migrated from %pI4 to %pI4\n", + src_mac, &f->remote_ip, &src_ip); + + f->remote_ip = src_ip; + f->updated = jiffies; + } else { + /* learned new entry */ + spin_lock(&vxlan->hash_lock); + err = vxlan_fdb_create(vxlan, src_mac, src_ip, + NUD_REACHABLE, + NLM_F_EXCL|NLM_F_CREATE); + spin_unlock(&vxlan->hash_lock); + } +} + + +/* See if multicast group is already in use by other ID */ +static bool vxlan_group_used(struct vxlan_net *vn, + const struct vxlan_dev *this) +{ + const struct vxlan_dev *vxlan; + struct hlist_node *node; + unsigned h; + + for (h = 0; h < VNI_HASH_SIZE; ++h) + hlist_for_each_entry(vxlan, node, &vn->vni_list[h], hlist) { + if (vxlan == this) + continue; + + if (!netif_running(vxlan->dev)) + continue; + + if (vxlan->gaddr == this->gaddr) + return true; + } + + return false; +} + +/* kernel equivalent to IP_ADD_MEMBERSHIP */ +static int vxlan_join_group(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id); + struct sock *sk = vn->sock->sk; + struct ip_mreqn mreq = { + .imr_multiaddr.s_addr = vxlan->gaddr, + }; + int err; + + /* Already a member of group */ + if (vxlan_group_used(vn, vxlan)) + return 0; + + /* Need to drop RTNL to call multicast join */ + rtnl_unlock(); + lock_sock(sk); + err = ip_mc_join_group(sk, &mreq); + release_sock(sk); + rtnl_lock(); + + return err; +} + + +/* kernel equivalent to IP_DROP_MEMBERSHIP */ +static int vxlan_leave_group(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id); + int err = 0; + struct sock *sk = vn->sock->sk; + struct ip_mreqn mreq = { + .imr_multiaddr.s_addr = vxlan->gaddr, + }; + + /* Only leave group when last vxlan is done. */ + if (vxlan_group_used(vn, vxlan)) + return 0; + + /* Need to drop RTNL to call multicast leave */ + rtnl_unlock(); + lock_sock(sk); + err = ip_mc_leave_group(sk, &mreq); + release_sock(sk); + rtnl_lock(); + + return err; +} + +/* Callback from net/ipv4/udp.c to receive packets */ +static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb) +{ + struct iphdr *oip; + struct vxlanhdr *vxh; + struct vxlan_dev *vxlan; + struct vxlan_stats *stats; + __u32 vni; + int err; + + /* pop off outer UDP header */ + __skb_pull(skb, sizeof(struct udphdr)); + + /* Need Vxlan and inner Ethernet header to be present */ + if (!pskb_may_pull(skb, sizeof(struct vxlanhdr))) + goto error; + + /* Drop packets with reserved bits set */ + vxh = (struct vxlanhdr *) skb->data; + if (vxh->vx_flags != htonl(VXLAN_FLAGS) || + (vxh->vx_vni & htonl(0xff))) { + netdev_dbg(skb->dev, "invalid vxlan flags=%#x vni=%#x\n", + ntohl(vxh->vx_flags), ntohl(vxh->vx_vni)); + goto error; + } + + __skb_pull(skb, sizeof(struct vxlanhdr)); + skb_postpull_rcsum(skb, eth_hdr(skb), sizeof(struct vxlanhdr)); + + /* Is this VNI defined? */ + vni = ntohl(vxh->vx_vni) >> 8; + vxlan = vxlan_find_vni(sock_net(sk), vni); + if (!vxlan) { + netdev_dbg(skb->dev, "unknown vni %d\n", vni); + goto drop; + } + + if (!pskb_may_pull(skb, ETH_HLEN)) { + vxlan->dev->stats.rx_length_errors++; + vxlan->dev->stats.rx_errors++; + goto drop; + } + + /* Re-examine inner Ethernet packet */ + oip = ip_hdr(skb); + skb->protocol = eth_type_trans(skb, vxlan->dev); + skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN); + + /* Ignore packet loops (and multicast echo) */ + if (compare_ether_addr(eth_hdr(skb)->h_source, + vxlan->dev->dev_addr) == 0) + goto drop; + + if (vxlan->learn) + vxlan_snoop(skb->dev, oip->saddr, eth_hdr(skb)->h_source); + + __skb_tunnel_rx(skb, vxlan->dev); + skb_reset_network_header(skb); + + err = IP_ECN_decapsulate(oip, skb); + if (unlikely(err)) { + if (log_ecn_error) + net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n", + &oip->saddr, oip->tos); + if (err > 1) { + ++vxlan->dev->stats.rx_frame_errors; + ++vxlan->dev->stats.rx_errors; + goto drop; + } + } + + stats = this_cpu_ptr(vxlan->stats); + u64_stats_update_begin(&stats->syncp); + stats->rx_packets++; + stats->rx_bytes += skb->len; + u64_stats_update_end(&stats->syncp); + + netif_rx(skb); + + return 0; +error: + /* Put UDP header back */ + __skb_push(skb, sizeof(struct udphdr)); + + return 1; +drop: + /* Consume bad packet */ + kfree_skb(skb); + return 0; +} + +/* Extract dsfield from inner protocol */ +static inline u8 vxlan_get_dsfield(const struct iphdr *iph, + const struct sk_buff *skb) +{ + if (skb->protocol == htons(ETH_P_IP)) + return iph->tos; + else if (skb->protocol == htons(ETH_P_IPV6)) + return ipv6_get_dsfield((const struct ipv6hdr *)iph); + else + return 0; +} + +/* Propogate ECN bits out */ +static inline u8 vxlan_ecn_encap(u8 tos, + const struct iphdr *iph, + const struct sk_buff *skb) +{ + u8 inner = vxlan_get_dsfield(iph, skb); + + return INET_ECN_encapsulate(tos, inner); +} + +/* Transmit local packets over Vxlan + * + * Outer IP header inherits ECN and DF from inner header. + * Outer UDP destination is the VXLAN assigned port. + * source port is based on hash of flow if available + * otherwise use a random value + */ +static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct rtable *rt; + const struct ethhdr *eth; + const struct iphdr *old_iph; + struct iphdr *iph; + struct vxlanhdr *vxh; + struct udphdr *uh; + struct flowi4 fl4; + struct vxlan_fdb *f; + unsigned int pkt_len = skb->len; + u32 hash; + __be32 dst; + __be16 df = 0; + __u8 tos, ttl; + int err; + + /* Need space for new headers (invalidates iph ptr) */ + if (skb_cow_head(skb, VXLAN_HEADROOM)) + goto drop; + + eth = (void *)skb->data; + old_iph = ip_hdr(skb); + + if (!is_multicast_ether_addr(eth->h_dest) && + (f = vxlan_find_mac(vxlan, eth->h_dest))) + dst = f->remote_ip; + else if (vxlan->gaddr) { + dst = vxlan->gaddr; + } else + goto drop; + + ttl = vxlan->ttl; + if (!ttl && IN_MULTICAST(ntohl(dst))) + ttl = 1; + + tos = vxlan->tos; + if (tos == 1) + tos = vxlan_get_dsfield(old_iph, skb); + + hash = skb_get_rxhash(skb); + + rt = ip_route_output_gre(dev_net(dev), &fl4, dst, + vxlan->saddr, vxlan->vni, + RT_TOS(tos), vxlan->link); + if (IS_ERR(rt)) { + netdev_dbg(dev, "no route to %pI4\n", &dst); + dev->stats.tx_carrier_errors++; + goto tx_error; + } + + if (rt->dst.dev == dev) { + netdev_dbg(dev, "circular route to %pI4\n", &dst); + ip_rt_put(rt); + dev->stats.collisions++; + goto tx_error; + } + + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); + IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | + IPSKB_REROUTED); + skb_dst_drop(skb); + skb_dst_set(skb, &rt->dst); + + vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh)); + vxh->vx_flags = htonl(VXLAN_FLAGS); + vxh->vx_vni = htonl(vxlan->vni << 8); + + __skb_push(skb, sizeof(*uh)); + skb_reset_transport_header(skb); + uh = udp_hdr(skb); + + uh->dest = htons(vxlan_port); + uh->source = hash ? :random32(); + + uh->len = htons(skb->len); + uh->check = 0; + + __skb_push(skb, sizeof(*iph)); + skb_reset_network_header(skb); + iph = ip_hdr(skb); + iph->version = 4; + iph->ihl = sizeof(struct iphdr) >> 2; + iph->frag_off = df; + iph->protocol = IPPROTO_UDP; + iph->tos = vxlan_ecn_encap(tos, old_iph, skb); + iph->daddr = fl4.daddr; + iph->saddr = fl4.saddr; + iph->ttl = ttl ? : ip4_dst_hoplimit(&rt->dst); + + /* See __IPTUNNEL_XMIT */ + skb->ip_summed = CHECKSUM_NONE; + ip_select_ident(iph, &rt->dst, NULL); + + err = ip_local_out(skb); + if (likely(net_xmit_eval(err) == 0)) { + struct vxlan_stats *stats = this_cpu_ptr(vxlan->stats); + + u64_stats_update_begin(&stats->syncp); + stats->tx_packets++; + stats->tx_bytes += pkt_len; + u64_stats_update_end(&stats->syncp); + } else { + dev->stats.tx_errors++; + dev->stats.tx_aborted_errors++; + } + return NETDEV_TX_OK; + +drop: + dev->stats.tx_dropped++; + goto tx_free; + +tx_error: + dev->stats.tx_errors++; +tx_free: + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} + +/* Walk the forwarding table and purge stale entries */ +static void vxlan_cleanup(unsigned long arg) +{ + struct vxlan_dev *vxlan = (struct vxlan_dev *) arg; + unsigned long next_timer = jiffies + FDB_AGE_INTERVAL; + unsigned int h; + + if (!netif_running(vxlan->dev)) + return; + + spin_lock_bh(&vxlan->hash_lock); + for (h = 0; h < FDB_HASH_SIZE; ++h) { + struct hlist_node *p, *n; + hlist_for_each_safe(p, n, &vxlan->fdb_head[h]) { + struct vxlan_fdb *f + = container_of(p, struct vxlan_fdb, hlist); + unsigned long timeout; + + if (f->state == NUD_PERMANENT) + continue; + + timeout = f->used + vxlan->age_interval * HZ; + if (time_before_eq(timeout, jiffies)) { + netdev_dbg(vxlan->dev, + "garbage collect %pM\n", + f->eth_addr); + f->state = NUD_STALE; + vxlan_fdb_destroy(vxlan, f); + } else if (time_before(timeout, next_timer)) + next_timer = timeout; + } + } + spin_unlock_bh(&vxlan->hash_lock); + + mod_timer(&vxlan->age_timer, next_timer); +} + +/* Setup stats when device is created */ +static int vxlan_init(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + + vxlan->stats = alloc_percpu(struct vxlan_stats); + if (!vxlan->stats) + return -ENOMEM; + + return 0; +} + +/* Start ageing timer and join group when device is brought up */ +static int vxlan_open(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + int err; + + if (vxlan->gaddr) { + err = vxlan_join_group(dev); + if (err) + return err; + } + + if (vxlan->age_interval) + mod_timer(&vxlan->age_timer, jiffies + FDB_AGE_INTERVAL); + + return 0; +} + +/* Purge the forwarding table */ +static void vxlan_flush(struct vxlan_dev *vxlan) +{ + unsigned h; + + spin_lock_bh(&vxlan->hash_lock); + for (h = 0; h < FDB_HASH_SIZE; ++h) { + struct hlist_node *p, *n; + hlist_for_each_safe(p, n, &vxlan->fdb_head[h]) { + struct vxlan_fdb *f + = container_of(p, struct vxlan_fdb, hlist); + vxlan_fdb_destroy(vxlan, f); + } + } + spin_unlock_bh(&vxlan->hash_lock); +} + +/* Cleanup timer and forwarding table on shutdown */ +static int vxlan_stop(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + + if (vxlan->gaddr) + vxlan_leave_group(dev); + + del_timer_sync(&vxlan->age_timer); + + vxlan_flush(vxlan); + + return 0; +} + +/* Merge per-cpu statistics */ +static struct rtnl_link_stats64 *vxlan_stats64(struct net_device *dev, + struct rtnl_link_stats64 *stats) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + struct vxlan_stats tmp, sum = { 0 }; + unsigned int cpu; + + for_each_possible_cpu(cpu) { + unsigned int start; + const struct vxlan_stats *stats + = per_cpu_ptr(vxlan->stats, cpu); + + do { + start = u64_stats_fetch_begin_bh(&stats->syncp); + memcpy(&tmp, stats, sizeof(tmp)); + } while (u64_stats_fetch_retry_bh(&stats->syncp, start)); + + sum.tx_bytes += tmp.tx_bytes; + sum.tx_packets += tmp.tx_packets; + sum.rx_bytes += tmp.rx_bytes; + sum.rx_packets += tmp.rx_packets; + } + + stats->tx_bytes = sum.tx_bytes; + stats->tx_packets = sum.tx_packets; + stats->rx_bytes = sum.rx_bytes; + stats->rx_packets = sum.rx_packets; + + stats->multicast = dev->stats.multicast; + stats->rx_length_errors = dev->stats.rx_length_errors; + stats->rx_frame_errors = dev->stats.rx_frame_errors; + stats->rx_errors = dev->stats.rx_errors; + + stats->tx_dropped = dev->stats.tx_dropped; + stats->tx_carrier_errors = dev->stats.tx_carrier_errors; + stats->tx_aborted_errors = dev->stats.tx_aborted_errors; + stats->collisions = dev->stats.collisions; + stats->tx_errors = dev->stats.tx_errors; + + return stats; +} + +/* Stub, nothing needs to be done. */ +static void vxlan_set_multicast_list(struct net_device *dev) +{ +} + +static const struct net_device_ops vxlan_netdev_ops = { + .ndo_init = vxlan_init, + .ndo_open = vxlan_open, + .ndo_stop = vxlan_stop, + .ndo_start_xmit = vxlan_xmit, + .ndo_get_stats64 = vxlan_stats64, + .ndo_set_rx_mode = vxlan_set_multicast_list, + .ndo_change_mtu = eth_change_mtu, + .ndo_validate_addr = eth_validate_addr, + .ndo_set_mac_address = eth_mac_addr, + .ndo_fdb_add = vxlan_fdb_add, + .ndo_fdb_del = vxlan_fdb_delete, + .ndo_fdb_dump = vxlan_fdb_dump, +}; + +/* Info for udev, that this is a virtual tunnel endpoint */ +static struct device_type vxlan_type = { + .name = "vxlan", +}; + +static void vxlan_free(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + + free_percpu(vxlan->stats); + free_netdev(dev); +} + +/* Initialize the device structure. */ +static void vxlan_setup(struct net_device *dev) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + unsigned h; + + eth_hw_addr_random(dev); + ether_setup(dev); + + dev->netdev_ops = &vxlan_netdev_ops; + dev->destructor = vxlan_free; + SET_NETDEV_DEVTYPE(dev, &vxlan_type); + + dev->tx_queue_len = 0; + dev->features |= NETIF_F_LLTX; + dev->features |= NETIF_F_NETNS_LOCAL; + dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; + + spin_lock_init(&vxlan->hash_lock); + + init_timer_deferrable(&vxlan->age_timer); + vxlan->age_timer.function = vxlan_cleanup; + vxlan->age_timer.data = (unsigned long) vxlan; + + vxlan->dev = dev; + + for (h = 0; h < FDB_HASH_SIZE; ++h) + INIT_HLIST_HEAD(&vxlan->fdb_head[h]); +} + +static const struct nla_policy vxlan_policy[IFLA_VXLAN_MAX + 1] = { + [IFLA_VXLAN_ID] = { .type = NLA_U32 }, + [IFLA_VXLAN_GROUP] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, + [IFLA_VXLAN_LINK] = { .type = NLA_U32 }, + [IFLA_VXLAN_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) }, + [IFLA_VXLAN_TOS] = { .type = NLA_U8 }, + [IFLA_VXLAN_TTL] = { .type = NLA_U8 }, + [IFLA_VXLAN_LEARNING] = { .type = NLA_U8 }, + [IFLA_VXLAN_AGEING] = { .type = NLA_U32 }, + [IFLA_VXLAN_LIMIT] = { .type = NLA_U32 }, +}; + +static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + if (tb[IFLA_ADDRESS]) { + if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) { + pr_debug("invalid link address (not ethernet)\n"); + return -EINVAL; + } + + if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) { + pr_debug("invalid all zero ethernet address\n"); + return -EADDRNOTAVAIL; + } + } + + if (!data) + return -EINVAL; + + if (data[IFLA_VXLAN_ID]) { + __u32 id = nla_get_u32(data[IFLA_VXLAN_ID]); + if (id >= VXLAN_VID_MASK) + return -ERANGE; + } + + if (data[IFLA_VXLAN_GROUP]) { + __be32 gaddr = nla_get_be32(data[IFLA_VXLAN_GROUP]); + if (!IN_MULTICAST(ntohl(gaddr))) { + pr_debug("group address is not IPv4 multicast\n"); + return -EADDRNOTAVAIL; + } + } + return 0; +} + +static int vxlan_newlink(struct net *net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[]) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + __u32 vni; + int err; + + if (!data[IFLA_VXLAN_ID]) + return -EINVAL; + + vni = nla_get_u32(data[IFLA_VXLAN_ID]); + if (vxlan_find_vni(net, vni)) { + pr_info("duplicate VNI %u\n", vni); + return -EEXIST; + } + vxlan->vni = vni; + + if (data[IFLA_VXLAN_GROUP]) + vxlan->gaddr = nla_get_be32(data[IFLA_VXLAN_GROUP]); + + if (data[IFLA_VXLAN_LOCAL]) + vxlan->saddr = nla_get_be32(data[IFLA_VXLAN_LOCAL]); + + if (data[IFLA_VXLAN_LINK]) { + vxlan->link = nla_get_u32(data[IFLA_VXLAN_LINK]); + + if (!tb[IFLA_MTU]) { + struct net_device *lowerdev; + lowerdev = __dev_get_by_index(net, vxlan->link); + dev->mtu = lowerdev->mtu - VXLAN_HEADROOM; + } + } + + if (data[IFLA_VXLAN_TOS]) + vxlan->tos = nla_get_u8(data[IFLA_VXLAN_TOS]); + + if (!data[IFLA_VXLAN_LEARNING] || nla_get_u8(data[IFLA_VXLAN_LEARNING])) + vxlan->learn = true; + + if (data[IFLA_VXLAN_AGEING]) + vxlan->age_interval = nla_get_u32(data[IFLA_VXLAN_AGEING]); + else + vxlan->age_interval = FDB_AGE_DEFAULT; + + if (data[IFLA_VXLAN_LIMIT]) + vxlan->addrmax = nla_get_u32(data[IFLA_VXLAN_LIMIT]); + + err = register_netdevice(dev); + if (!err) + hlist_add_head_rcu(&vxlan->hlist, vni_head(net, vxlan->vni)); + + return err; +} + +static void vxlan_dellink(struct net_device *dev, struct list_head *head) +{ + struct vxlan_dev *vxlan = netdev_priv(dev); + + hlist_del_rcu(&vxlan->hlist); + + unregister_netdevice_queue(dev, head); +} + +static size_t vxlan_get_size(const struct net_device *dev) +{ + + return nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_ID */ + nla_total_size(sizeof(__be32)) +/* IFLA_VXLAN_GROUP */ + nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_LINK */ + nla_total_size(sizeof(__be32))+ /* IFLA_VXLAN_LOCAL */ + nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_TTL */ + nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_TOS */ + nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_LEARNING */ + nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_AGEING */ + nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_LIMIT */ + 0; +} + +static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev) +{ + const struct vxlan_dev *vxlan = netdev_priv(dev); + + if (nla_put_u32(skb, IFLA_VXLAN_ID, vxlan->vni)) + goto nla_put_failure; + + if (vxlan->gaddr && nla_put_u32(skb, IFLA_VXLAN_GROUP, vxlan->gaddr)) + goto nla_put_failure; + + if (vxlan->link && nla_put_u32(skb, IFLA_VXLAN_LINK, vxlan->link)) + goto nla_put_failure; + + if (vxlan->saddr && nla_put_u32(skb, IFLA_VXLAN_LOCAL, vxlan->saddr)) + goto nla_put_failure; + + if (nla_put_u8(skb, IFLA_VXLAN_TTL, vxlan->ttl) || + nla_put_u8(skb, IFLA_VXLAN_TOS, vxlan->tos) || + nla_put_u8(skb, IFLA_VXLAN_LEARNING, vxlan->learn) || + nla_put_u32(skb, IFLA_VXLAN_AGEING, vxlan->age_interval) || + nla_put_u32(skb, IFLA_VXLAN_LIMIT, vxlan->addrmax)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static struct rtnl_link_ops vxlan_link_ops __read_mostly = { + .kind = "vxlan", + .maxtype = IFLA_VXLAN_MAX, + .policy = vxlan_policy, + .priv_size = sizeof(struct vxlan_dev), + .setup = vxlan_setup, + .validate = vxlan_validate, + .newlink = vxlan_newlink, + .dellink = vxlan_dellink, + .get_size = vxlan_get_size, + .fill_info = vxlan_fill_info, +}; + +static __net_init int vxlan_init_net(struct net *net) +{ + struct vxlan_net *vn = net_generic(net, vxlan_net_id); + struct sock *sk; + struct sockaddr_in vxlan_addr = { + .sin_family = AF_INET, + .sin_addr.s_addr = htonl(INADDR_ANY), + }; + int rc; + unsigned h; + + /* Create UDP socket for encapsulation receive. */ + rc = sock_create_kern(AF_INET, SOCK_DGRAM, IPPROTO_UDP, &vn->sock); + if (rc < 0) { + pr_debug("UDP socket create failed\n"); + return rc; + } + /* Put in proper namespace */ + sk = vn->sock->sk; + sk_change_net(sk, net); + + vxlan_addr.sin_port = htons(vxlan_port); + + rc = kernel_bind(vn->sock, (struct sockaddr *) &vxlan_addr, + sizeof(vxlan_addr)); + if (rc < 0) { + pr_debug("bind for UDP socket %pI4:%u (%d)\n", + &vxlan_addr.sin_addr, ntohs(vxlan_addr.sin_port), rc); + sk_release_kernel(sk); + vn->sock = NULL; + return rc; + } + + /* Disable multicast loopback */ + inet_sk(sk)->mc_loop = 0; + + /* Mark socket as an encapsulation socket. */ + udp_sk(sk)->encap_type = 1; + udp_sk(sk)->encap_rcv = vxlan_udp_encap_recv; + udp_encap_enable(); + + for (h = 0; h < VNI_HASH_SIZE; ++h) + INIT_HLIST_HEAD(&vn->vni_list[h]); + + return 0; +} + +static __net_exit void vxlan_exit_net(struct net *net) +{ + struct vxlan_net *vn = net_generic(net, vxlan_net_id); + + if (vn->sock) { + sk_release_kernel(vn->sock->sk); + vn->sock = NULL; + } +} + +static struct pernet_operations vxlan_net_ops = { + .init = vxlan_init_net, + .exit = vxlan_exit_net, + .id = &vxlan_net_id, + .size = sizeof(struct vxlan_net), +}; + +static int __init vxlan_init_module(void) +{ + int rc; + + get_random_bytes(&vxlan_salt, sizeof(vxlan_salt)); + + rc = register_pernet_device(&vxlan_net_ops); + if (rc) + goto out1; + + rc = rtnl_link_register(&vxlan_link_ops); + if (rc) + goto out2; + + return 0; + +out2: + unregister_pernet_device(&vxlan_net_ops); +out1: + return rc; +} +module_init(vxlan_init_module); + +static void __exit vxlan_cleanup_module(void) +{ + rtnl_link_unregister(&vxlan_link_ops); + unregister_pernet_device(&vxlan_net_ops); +} +module_exit(vxlan_cleanup_module); + +MODULE_LICENSE("GPL"); +MODULE_VERSION(VXLAN_VERSION); +MODULE_AUTHOR("Stephen Hemminger <shemminger@vyatta.com>"); +MODULE_ALIAS_RTNL_LINK("vxlan"); |
