--- /dev/null
+/*
+ * Copyright (c) 2007-2013 Nicira, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ *
+ * This code is derived from kernel vxlan module.
+ */
+
+#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/if_vlan.h>
+#include <linux/hash.h>
+#include <linux/ethtool.h>
+#include <net/arp.h>
+#include <net/ndisc.h>
+#include <net/ip.h>
+#include <net/ip_tunnels.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>
+#include <net/vxlan.h>
+
+#include "checksum.h"
+#include "compat.h"
+#include "gso.h"
+#include "vlan.h"
+
+#define PORT_HASH_BITS 8
+#define PORT_HASH_SIZE (1<<PORT_HASH_BITS)
+
+#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_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
+
+#define VXLAN_FLAGS 0x08000000 /* struct vxlanhdr.vx_flags required value. */
+
+/* VXLAN protocol header */
+struct vxlanhdr {
+ __be32 vx_flags;
+ __be32 vx_vni;
+};
+
+static int vxlan_net_id;
+
+/* per-network namespace private data for this module */
+struct vxlan_net {
+ struct hlist_head sock_list[PORT_HASH_SIZE];
+ struct mutex sock_lock; /* RTNL lock nests inside this lock. */
+};
+
+/* Socket hash table head */
+static inline struct hlist_head *vs_head(struct net *net, __be16 port)
+{
+ struct vxlan_net *vn = net_generic(net, vxlan_net_id);
+
+ return &vn->sock_list[hash_32(ntohs(port), PORT_HASH_BITS)];
+}
+
+/* Find VXLAN socket based on network namespace and UDP port */
+static struct vxlan_sock *vxlan_find_port(struct net *net, __be16 port)
+{
+ struct vxlan_sock *vs;
+
+ hlist_for_each_entry_rcu(vs, vs_head(net, port), hlist) {
+ if (inet_sport(vs->sock->sk) == port)
+ return vs;
+ }
+ return NULL;
+}
+
+/* Callback from net/ipv4/udp.c to receive packets */
+static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
+{
+ struct vxlan_handler *vh;
+ struct vxlan_sock *vs;
+ struct vxlanhdr *vxh;
+
+ /* Need Vxlan and inner Ethernet header to be present */
+ if (!pskb_may_pull(skb, VXLAN_HLEN))
+ goto error;
+
+ /* Return packets with reserved bits set */
+ vxh = (struct vxlanhdr *)(udp_hdr(skb) + 1);
+ if (vxh->vx_flags != htonl(VXLAN_FLAGS) ||
+ (vxh->vx_vni & htonl(0xff))) {
+ pr_warn("invalid vxlan flags=%#x vni=%#x\n",
+ ntohl(vxh->vx_flags), ntohl(vxh->vx_vni));
+ goto error;
+ }
+
+ if (iptunnel_pull_header(skb, VXLAN_HLEN, htons(ETH_P_TEB)))
+ goto drop;
+
+ vs = vxlan_find_port(sock_net(sk), inet_sport(sk));
+ if (!vs)
+ goto drop;
+
+ list_for_each_entry_rcu(vh, &vs->handler_list, node) {
+ if (vh->rcv(vh, skb, vxh->vx_vni) == PACKET_RCVD)
+ return 0;
+ }
+
+drop:
+ /* Consume bad packet */
+ kfree_skb(skb);
+ return 0;
+
+error:
+ /* Return non vxlan pkt */
+ return 1;
+}
+
+static void vxlan_sock_put(struct sk_buff *skb)
+{
+ sock_put(skb->sk);
+}
+
+/* On transmit, associate with the tunnel socket */
+static void vxlan_set_owner(struct sock *sk, struct sk_buff *skb)
+{
+ skb_orphan(skb);
+ sock_hold(sk);
+ skb->sk = sk;
+ skb->destructor = vxlan_sock_put;
+}
+
+/* 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
+ */
+__be16 vxlan_src_port(__u16 port_min, __u16 port_max, struct sk_buff *skb)
+{
+ unsigned int range = (port_max - port_min) + 1;
+ u32 hash;
+
+ hash = skb_get_rxhash(skb);
+ if (!hash)
+ hash = jhash(skb->data, 2 * ETH_ALEN,
+ (__force u32) skb->protocol);
+
+ return htons((((u64) hash * range) >> 32) + port_min);
+}
+
+static void vxlan_gso(struct sk_buff *skb)
+{
+ int udp_offset = skb_transport_offset(skb);
+ struct udphdr *uh;
+
+ uh = udp_hdr(skb);
+ uh->len = htons(skb->len - udp_offset);
+
+ /* csum segment if tunnel sets skb with csum. */
+ if (unlikely(uh->check)) {
+ struct iphdr *iph = ip_hdr(skb);
+
+ uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
+ skb->len - udp_offset,
+ IPPROTO_UDP, 0);
+ uh->check = csum_fold(skb_checksum(skb, udp_offset,
+ skb->len - udp_offset, 0));
+
+ if (uh->check == 0)
+ uh->check = CSUM_MANGLED_0;
+
+ }
+ skb->ip_summed = CHECKSUM_NONE;
+}
+
+static int handle_offloads(struct sk_buff *skb)
+{
+ if (skb_is_gso(skb)) {
+ OVS_GSO_CB(skb)->fix_segment = vxlan_gso;
+ } else {
+ if (skb->ip_summed != CHECKSUM_PARTIAL)
+ skb->ip_summed = CHECKSUM_NONE;
+ }
+ return 0;
+}
+
+int vxlan_xmit_skb(struct net *net, struct vxlan_handler *vh,
+ struct rtable *rt, struct sk_buff *skb,
+ __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
+ __be16 src_port, __be16 dst_port, __be32 vni)
+{
+ struct vxlanhdr *vxh;
+ struct udphdr *uh;
+ int min_headroom;
+ int err;
+
+ skb_reset_inner_headers(skb);
+
+ min_headroom = LL_RESERVED_SPACE(rt_dst(rt).dev) + rt_dst(rt).header_len
+ + VXLAN_HLEN + sizeof(struct iphdr)
+ + (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
+
+ /* Need space for new headers (invalidates iph ptr) */
+ err = skb_cow_head(skb, min_headroom);
+ if (unlikely(err))
+ return err;
+
+ if (unlikely(vlan_deaccel_tag(skb)))
+ return -ENOMEM;
+
+ vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
+ vxh->vx_flags = htonl(VXLAN_FLAGS);
+ vxh->vx_vni = vni;
+
+ __skb_push(skb, sizeof(*uh));
+ skb_reset_transport_header(skb);
+ uh = udp_hdr(skb);
+
+ uh->dest = dst_port;
+ uh->source = src_port;
+
+ uh->len = htons(skb->len);
+ uh->check = 0;
+
+ vxlan_set_owner(vh->vs->sock->sk, skb);
+
+ err = handle_offloads(skb);
+ if (err)
+ return err;
+
+ return iptunnel_xmit(net, rt, skb, src, dst,
+ IPPROTO_UDP, tos, ttl, df);
+}
+
+static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port)
+{
+ struct vxlan_sock *vs;
+ struct sock *sk;
+ struct sockaddr_in vxlan_addr = {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl(INADDR_ANY),
+ .sin_port = port,
+ };
+ int rc;
+
+ vs = kmalloc(sizeof(*vs), GFP_KERNEL);
+ if (!vs)
+ return ERR_PTR(-ENOMEM);
+
+ /* Create UDP socket for encapsulation receive. */
+ rc = sock_create_kern(AF_INET, SOCK_DGRAM, IPPROTO_UDP, &vs->sock);
+ if (rc < 0) {
+ pr_debug("UDP socket create failed\n");
+ kfree(vs);
+ return ERR_PTR(rc);
+ }
+
+ /* Put in proper namespace */
+ sk = vs->sock->sk;
+ sk_change_net(sk, net);
+
+ rc = kernel_bind(vs->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);
+ kfree(vs);
+ return ERR_PTR(rc);
+ }
+
+ /* Disable multicast loopback */
+ inet_sk(sk)->mc_loop = 0;
+ INIT_LIST_HEAD(&vs->handler_list);
+ hlist_add_head_rcu(&vs->hlist, vs_head(net, port));
+
+ /* Mark socket as an encapsulation socket. */
+ udp_sk(sk)->encap_type = 1;
+ udp_sk(sk)->encap_rcv = vxlan_udp_encap_recv;
+ udp_encap_enable();
+
+ return vs;
+}
+
+static void rcu_free_vs_callback(struct rcu_head *rcu)
+{
+ struct vxlan_sock *vs = container_of(rcu, struct vxlan_sock, rcu);
+
+ kfree(vs);
+}
+
+static void vxlan_socket_del(struct vxlan_sock *vs)
+{
+ if (list_empty(&vs->handler_list)) {
+ hlist_del_rcu(&vs->hlist);
+
+ sk_release_kernel(vs->sock->sk);
+ call_rcu(&vs->rcu, rcu_free_vs_callback);
+ }
+}
+
+static int vxlan_init_module(void);
+static void vxlan_cleanup_module(void);
+
+static void rcu_free_vh_callback(struct rcu_head *rcu)
+{
+ struct vxlan_handler *vh = container_of(rcu, struct vxlan_handler, rcu);
+
+ kfree(vh);
+}
+
+static void vh_del_work(struct work_struct *work)
+{
+ struct vxlan_handler *vh = container_of(work, struct vxlan_handler, del_work);
+ struct vxlan_sock *vs = vh->vs;
+ struct net *net = sock_net(vs->sock->sk);
+ struct vxlan_net *vn = net_generic(net, vxlan_net_id);
+
+ mutex_lock(&vn->sock_lock);
+
+ list_del_rcu(&vh->node);
+ call_rcu(&vh->rcu, rcu_free_vh_callback);
+ vxlan_socket_del(vs);
+
+ mutex_unlock(&vn->sock_lock);
+
+ vxlan_cleanup_module();
+}
+
+struct vxlan_handler *vxlan_handler_add(struct net *net,
+ __be16 portno, vxlan_rcv_t *rcv,
+ void *data, int priority, bool create)
+{
+ struct vxlan_net *vn;
+ struct vxlan_sock *vs;
+ struct vxlan_handler *vh;
+ struct vxlan_handler *new;
+ int err;
+
+ err = vxlan_init_module();
+ if (err)
+ return ERR_PTR(err);
+
+ vn = net_generic(net, vxlan_net_id);
+ mutex_lock(&vn->sock_lock);
+ /* Look to see if can reuse socket */
+ vs = vxlan_find_port(net, portno);
+ if (!vs) {
+ vs = vxlan_socket_create(net, portno);
+ if (IS_ERR(vs)) {
+ new = (void *) vs;
+ goto out;
+ }
+ }
+
+ /* Try existing vxlan hanlders for this socket. */
+ list_for_each_entry(vh, &vs->handler_list, node) {
+ if (vh->rcv == rcv) {
+ if (create) {
+ vxlan_socket_del(vs);
+ new = ERR_PTR(-EEXIST);
+ goto out;
+ }
+ atomic_inc(&vh->refcnt);
+ new = vh;
+ goto out;
+ }
+ }
+
+ new = kzalloc(sizeof(*new), GFP_KERNEL);
+ if (!new) {
+ vxlan_socket_del(vs);
+ new = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ new->rcv = rcv;
+ new->vs = vs;
+ atomic_set(&new->refcnt, 1);
+ INIT_WORK(&new->del_work, vh_del_work);
+ new->data = data;
+ new->priority = priority;
+
+ list_for_each_entry(vh, &vs->handler_list, node) {
+ if (vh->priority > priority) {
+ list_add_tail_rcu(&new->node, &vh->node);
+ goto out;
+ }
+ }
+
+ list_add_tail_rcu(&new->node, &vs->handler_list);
+out:
+ mutex_unlock(&vn->sock_lock);
+ return new;
+}
+
+void vxlan_handler_put(struct vxlan_handler *vh)
+{
+ BUG_ON(!vh->vs);
+
+ if (atomic_dec_and_test(&vh->refcnt))
+ queue_work(&vh->del_work);
+}
+
+static __net_init int vxlan_init_net(struct net *net)
+{
+ struct vxlan_net *vn = net_generic(net, vxlan_net_id);
+ unsigned int h;
+
+ mutex_init(&vn->sock_lock);
+
+ for (h = 0; h < PORT_HASH_SIZE; ++h)
+ INIT_HLIST_HEAD(&vn->sock_list[h]);
+
+ return 0;
+}
+
+static struct pernet_operations vxlan_net_ops = {
+ .init = vxlan_init_net,
+ .id = &vxlan_net_id,
+ .size = sizeof(struct vxlan_net),
+};
+
+static int refcnt;
+static DEFINE_MUTEX(init_lock);
+DEFINE_COMPAT_PNET_REG_FUNC(device);
+
+static int vxlan_init_module(void)
+{
+ int err = 0;
+
+ mutex_lock(&init_lock);
+ if (refcnt)
+ goto out;
+ err = register_pernet_device(&vxlan_net_ops);
+out:
+ if (!err)
+ refcnt++;
+ mutex_unlock(&init_lock);
+ return err;
+}
+
+static void vxlan_cleanup_module(void)
+{
+ mutex_lock(&init_lock);
+ refcnt--;
+ if (refcnt)
+ goto out;
+ unregister_pernet_device(&vxlan_net_ops);
+out:
+ mutex_unlock(&init_lock);
+}
git://git.onelab.eu / sliver-openvswitch.git / blobdiff