/* * VXLAN: Virtual eXtensible 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/hash.h> #include <net/arp.h> #include <net/ndisc.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) /* IP header + UDP + VXLAN + Ethernet header */ #define VXLAN_HEADROOM (20 + 8 + 8 + 14) #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 */ __u16 port_min; /* source port range */ __u16 port_max; __u8 tos; /* TOS override */ __u8 ttl; u32 flags; /* VXLAN_F_* below */ unsigned long age_interval; struct timer_list age_timer; spinlock_t hash_lock; unsigned int addrcnt; unsigned int addrmax; struct hlist_head fdb_head[FDB_HASH_SIZE]; }; #define VXLAN_F_LEARN 0x01 #define VXLAN_F_PROXY 0x02 #define VXLAN_F_RSC 0x04 #define VXLAN_F_L2MISS 0x08 #define VXLAN_F_L3MISS 0x10 /* 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; bool send_ip, send_eth; nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags); if (nlh == NULL) return -EMSGSIZE; ndm = nlmsg_data(nlh); memset(ndm, 0, sizeof(*ndm)); send_eth = send_ip = true; if (type == RTM_GETNEIGH) { ndm->ndm_family = AF_INET; send_ip = fdb->remote_ip != 0; send_eth = !is_zero_ether_addr(fdb->eth_addr); } else 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 (send_eth && nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->eth_addr)) goto nla_put_failure; if (send_ip && 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); } static void vxlan_ip_miss(struct net_device *dev, __be32 ipa) { struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_fdb f; memset(&f, 0, sizeof f); f.state = NUD_STALE; f.remote_ip = ipa; /* goes to NDA_DST */ vxlan_fdb_notify(vxlan, &f, RTM_GETNEIGH); } static void vxlan_fdb_miss(struct vxlan_dev *vxlan, const u8 eth_addr[ETH_ALEN]) { struct vxlan_fdb f; memset(&f, 0, sizeof f); f.state = NUD_STALE; memcpy(f.eth_addr, eth_addr, ETH_ALEN); vxlan_fdb_notify(vxlan, &f, RTM_GETNEIGH); } /* 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, .imr_ifindex = vxlan->link, }; 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, .imr_ifindex = vxlan->link, }; /* 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)); /* 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; } skb_reset_mac_header(skb); /* Re-examine inner Ethernet packet */ oip = ip_hdr(skb); skb->protocol = eth_type_trans(skb, vxlan->dev); /* Ignore packet loops (and multicast echo) */ if (compare_ether_addr(eth_hdr(skb)->h_source, vxlan->dev->dev_addr) == 0) goto drop; if (vxlan->flags & VXLAN_F_LEARN) vxlan_snoop(skb->dev, oip->saddr, eth_hdr(skb)->h_source); __skb_tunnel_rx(skb, vxlan->dev); skb_reset_network_header(skb); /* If the NIC driver gave us an encapsulated packet with * CHECKSUM_UNNECESSARY and Rx checksum feature is enabled, * leave the CHECKSUM_UNNECESSARY, the device checksummed it * for us. Otherwise force the upper layers to verify it. */ if (skb->ip_summed != CHECKSUM_UNNECESSARY || !skb->encapsulation || !(vxlan->dev->features & NETIF_F_RXCSUM)) skb->ip_summed = CHECKSUM_NONE; skb->encapsulation = 0; 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; } static int arp_reduce(struct net_device *dev, struct sk_buff *skb) { struct vxlan_dev *vxlan = netdev_priv(dev); struct arphdr *parp; u8 *arpptr, *sha; __be32 sip, tip; struct neighbour *n; if (dev->flags & IFF_NOARP) goto out; if (!pskb_may_pull(skb, arp_hdr_len(dev))) { dev->stats.tx_dropped++; goto out; } parp = arp_hdr(skb); if ((parp->ar_hrd != htons(ARPHRD_ETHER) && parp->ar_hrd != htons(ARPHRD_IEEE802)) || parp->ar_pro != htons(ETH_P_IP) || parp->ar_op != htons(ARPOP_REQUEST) || parp->ar_hln != dev->addr_len || parp->ar_pln != 4) goto out; arpptr = (u8 *)parp + sizeof(struct arphdr); sha = arpptr; arpptr += dev->addr_len; /* sha */ memcpy(&sip, arpptr, sizeof(sip)); arpptr += sizeof(sip); arpptr += dev->addr_len; /* tha */ memcpy(&tip, arpptr, sizeof(tip)); if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip)) goto out; n = neigh_lookup(&arp_tbl, &tip, dev); if (n) { struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_fdb *f; struct sk_buff *reply; if (!(n->nud_state & NUD_CONNECTED)) { neigh_release(n); goto out; } f = vxlan_find_mac(vxlan, n->ha); if (f && f->remote_ip == 0) { /* bridge-local neighbor */ neigh_release(n); goto out; } reply = arp_create(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, n->ha, sha); neigh_release(n); skb_reset_mac_header(reply); __skb_pull(reply, skb_network_offset(reply)); reply->ip_summed = CHECKSUM_UNNECESSARY; reply->pkt_type = PACKET_HOST; if (netif_rx_ni(reply) == NET_RX_DROP) dev->stats.rx_dropped++; } else if (vxlan->flags & VXLAN_F_L3MISS) vxlan_ip_miss(dev, tip); out: consume_skb(skb); return NETDEV_TX_OK; } static bool route_shortcircuit(struct net_device *dev, struct sk_buff *skb) { struct vxlan_dev *vxlan = netdev_priv(dev); struct neighbour *n; struct iphdr *pip; if (is_multicast_ether_addr(eth_hdr(skb)->h_dest)) return false; n = NULL; switch (ntohs(eth_hdr(skb)->h_proto)) { case ETH_P_IP: if (!pskb_may_pull(skb, sizeof(struct iphdr))) return false; pip = ip_hdr(skb); n = neigh_lookup(&arp_tbl, &pip->daddr, dev); break; default: return false; } if (n) { bool diff; diff = compare_ether_addr(eth_hdr(skb)->h_dest, n->ha) != 0; if (diff) { memcpy(eth_hdr(skb)->h_source, eth_hdr(skb)->h_dest, dev->addr_len); memcpy(eth_hdr(skb)->h_dest, n->ha, dev->addr_len); } neigh_release(n); return diff; } else if (vxlan->flags & VXLAN_F_L3MISS) vxlan_ip_miss(dev, pip->daddr); return false; } /* 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); } static void vxlan_sock_free(struct sk_buff *skb) { sock_put(skb->sk); } /* On transmit, associate with the tunnel socket */ static void vxlan_set_owner(struct net_device *dev, struct sk_buff *skb) { struct vxlan_net *vn = net_generic(dev_net(dev), vxlan_net_id); struct sock *sk = vn->sock->sk; skb_orphan(skb); sock_hold(sk); skb->sk = sk; skb->destructor = vxlan_sock_free; } /* Compute source port for outgoing packet * first choice to use L4 flow hash since it will spread * better and maybe available from hardware * secondary choice is to use jhash on the Ethernet header */ static u16 vxlan_src_port(const struct vxlan_dev *vxlan, struct sk_buff *skb) { unsigned int range = (vxlan->port_max - vxlan->port_min) + 1; u32 hash; hash = skb_get_rxhash(skb); if (!hash) hash = jhash(skb->data, 2 * ETH_ALEN, (__force u32) skb->protocol); return (((u64) hash * range) >> 32) + vxlan->port_min; } /* 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 */ 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 iphdr *old_iph; struct ethhdr *eth; struct iphdr *iph; struct vxlanhdr *vxh; struct udphdr *uh; struct flowi4 fl4; unsigned int pkt_len = skb->len; __be32 dst; __u16 src_port; __be16 df = 0; __u8 tos, ttl; int err; bool did_rsc = false; const struct vxlan_fdb *f; skb_reset_mac_header(skb); eth = eth_hdr(skb); if ((vxlan->flags & VXLAN_F_PROXY) && ntohs(eth->h_proto) == ETH_P_ARP) return arp_reduce(dev, skb); else if ((vxlan->flags&VXLAN_F_RSC) && ntohs(eth->h_proto) == ETH_P_IP) did_rsc = route_shortcircuit(dev, skb); f = vxlan_find_mac(vxlan, eth->h_dest); if (f == NULL) { did_rsc = false; dst = vxlan->gaddr; if (!dst && (vxlan->flags & VXLAN_F_L2MISS) && !is_multicast_ether_addr(eth->h_dest)) vxlan_fdb_miss(vxlan, eth->h_dest); } else dst = f->remote_ip; if (!dst) { if (did_rsc) { __skb_pull(skb, skb_network_offset(skb)); skb->ip_summed = CHECKSUM_NONE; skb->pkt_type = PACKET_HOST; /* short-circuited back to local bridge */ if (netif_rx(skb) == NET_RX_SUCCESS) { 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; } goto drop; } if (!skb->encapsulation) { skb_reset_inner_headers(skb); skb->encapsulation = 1; } /* Need space for new headers (invalidates iph ptr) */ if (skb_cow_head(skb, VXLAN_HEADROOM)) goto drop; old_iph = ip_hdr(skb); ttl = vxlan->ttl; if (!ttl && IN_MULTICAST(ntohl(dst))) ttl = 1; tos = vxlan->tos; if (tos == 1) tos = vxlan_get_dsfield(old_iph, skb); src_port = vxlan_src_port(vxlan, skb); memset(&fl4, 0, sizeof(fl4)); fl4.flowi4_oif = vxlan->link; fl4.flowi4_tos = RT_TOS(tos); fl4.daddr = dst; fl4.saddr = vxlan->saddr; rt = ip_route_output_key(dev_net(dev), &fl4); 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 = htons(src_port); 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 = dst; iph->saddr = fl4.saddr; iph->ttl = ttl ? : ip4_dst_hoplimit(&rt->dst); vxlan_set_owner(dev, skb); /* See iptunnel_xmit() */ if (skb->ip_summed != CHECKSUM_PARTIAL) 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; int low, high; eth_hw_addr_random(dev); ether_setup(dev); dev->hard_header_len = ETH_HLEN + VXLAN_HEADROOM; 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->features |= NETIF_F_SG | NETIF_F_HW_CSUM; dev->features |= NETIF_F_RXCSUM; dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM; dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; 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; inet_get_local_port_range(&low, &high); vxlan->port_min = low; vxlan->port_max = high; 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 }, [IFLA_VXLAN_PORT_RANGE] = { .len = sizeof(struct ifla_vxlan_port_range) }, [IFLA_VXLAN_PROXY] = { .type = NLA_U8 }, [IFLA_VXLAN_RSC] = { .type = NLA_U8 }, [IFLA_VXLAN_L2MISS] = { .type = NLA_U8 }, [IFLA_VXLAN_L3MISS] = { .type = NLA_U8 }, }; 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; } } if (data[IFLA_VXLAN_PORT_RANGE]) { const struct ifla_vxlan_port_range *p = nla_data(data[IFLA_VXLAN_PORT_RANGE]); if (ntohs(p->high) < ntohs(p->low)) { pr_debug("port range %u .. %u not valid\n", ntohs(p->low), ntohs(p->high)); return -EINVAL; } } 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]))) { struct net_device *lowerdev = __dev_get_by_index(net, vxlan->link); if (!lowerdev) { pr_info("ifindex %d does not exist\n", vxlan->link); return -ENODEV; } if (!tb[IFLA_MTU]) dev->mtu = lowerdev->mtu - VXLAN_HEADROOM; /* update header length based on lower device */ dev->hard_header_len = lowerdev->hard_header_len + VXLAN_HEADROOM; } if (data[IFLA_VXLAN_TOS]) vxlan->tos = nla_get_u8(data[IFLA_VXLAN_TOS]); if (data[IFLA_VXLAN_TTL]) vxlan->ttl = nla_get_u8(data[IFLA_VXLAN_TTL]); if (!data[IFLA_VXLAN_LEARNING] || nla_get_u8(data[IFLA_VXLAN_LEARNING])) vxlan->flags |= VXLAN_F_LEARN; 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_PROXY] && nla_get_u8(data[IFLA_VXLAN_PROXY])) vxlan->flags |= VXLAN_F_PROXY; if (data[IFLA_VXLAN_RSC] && nla_get_u8(data[IFLA_VXLAN_RSC])) vxlan->flags |= VXLAN_F_RSC; if (data[IFLA_VXLAN_L2MISS] && nla_get_u8(data[IFLA_VXLAN_L2MISS])) vxlan->flags |= VXLAN_F_L2MISS; if (data[IFLA_VXLAN_L3MISS] && nla_get_u8(data[IFLA_VXLAN_L3MISS])) vxlan->flags |= VXLAN_F_L3MISS; if (data[IFLA_VXLAN_LIMIT]) vxlan->addrmax = nla_get_u32(data[IFLA_VXLAN_LIMIT]); if (data[IFLA_VXLAN_PORT_RANGE]) { const struct ifla_vxlan_port_range *p = nla_data(data[IFLA_VXLAN_PORT_RANGE]); vxlan->port_min = ntohs(p->low); vxlan->port_max = ntohs(p->high); } 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(__u8)) + /* IFLA_VXLAN_PROXY */ nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_RSC */ nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_L2MISS */ nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_L3MISS */ nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_AGEING */ nla_total_size(sizeof(__u32)) + /* IFLA_VXLAN_LIMIT */ nla_total_size(sizeof(struct ifla_vxlan_port_range)) + 0; } static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev) { const struct vxlan_dev *vxlan = netdev_priv(dev); struct ifla_vxlan_port_range ports = { .low = htons(vxlan->port_min), .high = htons(vxlan->port_max), }; if (nla_put_u32(skb, IFLA_VXLAN_ID, vxlan->vni)) goto nla_put_failure; if (vxlan->gaddr && nla_put_be32(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_be32(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->flags & VXLAN_F_LEARN)) || nla_put_u8(skb, IFLA_VXLAN_PROXY, !!(vxlan->flags & VXLAN_F_PROXY)) || nla_put_u8(skb, IFLA_VXLAN_RSC, !!(vxlan->flags & VXLAN_F_RSC)) || nla_put_u8(skb, IFLA_VXLAN_L2MISS, !!(vxlan->flags & VXLAN_F_L2MISS)) || nla_put_u8(skb, IFLA_VXLAN_L3MISS, !!(vxlan->flags & VXLAN_F_L3MISS)) || nla_put_u32(skb, IFLA_VXLAN_AGEING, vxlan->age_interval) || nla_put_u32(skb, IFLA_VXLAN_LIMIT, vxlan->addrmax)) goto nla_put_failure; if (nla_put(skb, IFLA_VXLAN_PORT_RANGE, sizeof(ports), &ports)) 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); struct vxlan_dev *vxlan; struct hlist_node *pos; unsigned h; rtnl_lock(); for (h = 0; h < VNI_HASH_SIZE; ++h) hlist_for_each_entry(vxlan, pos, &vn->vni_list[h], hlist) dev_close(vxlan->dev); rtnl_unlock(); 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");