kernel-ark/net/ipv6/ip6_vti.c
Steffen Klassert ccd740cbc6 vti6: Add pmtu handling to vti6_xmit.
We currently rely on the PMTU discovery of xfrm.
However if a packet is localy sent, the PMTU mechanism
of xfrm tries to to local socket notification what
might not work for applications like ping that don't
check for this. So add pmtu handling to vti6_xmit to
report MTU changes immediately.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-01 16:03:43 -07:00

1195 lines
28 KiB
C

/*
* IPv6 virtual tunneling interface
*
* Copyright (C) 2013 secunet Security Networks AG
*
* Author:
* Steffen Klassert <steffen.klassert@secunet.com>
*
* Based on:
* net/ipv6/ip6_tunnel.c
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/sockios.h>
#include <linux/icmp.h>
#include <linux/if.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/icmpv6.h>
#include <linux/init.h>
#include <linux/route.h>
#include <linux/rtnetlink.h>
#include <linux/netfilter_ipv6.h>
#include <linux/slab.h>
#include <linux/hash.h>
#include <linux/uaccess.h>
#include <linux/atomic.h>
#include <net/icmp.h>
#include <net/ip.h>
#include <net/ip_tunnels.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
#include <net/addrconf.h>
#include <net/ip6_tunnel.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#define HASH_SIZE_SHIFT 5
#define HASH_SIZE (1 << HASH_SIZE_SHIFT)
static u32 HASH(const struct in6_addr *addr1, const struct in6_addr *addr2)
{
u32 hash = ipv6_addr_hash(addr1) ^ ipv6_addr_hash(addr2);
return hash_32(hash, HASH_SIZE_SHIFT);
}
static int vti6_dev_init(struct net_device *dev);
static void vti6_dev_setup(struct net_device *dev);
static struct rtnl_link_ops vti6_link_ops __read_mostly;
static int vti6_net_id __read_mostly;
struct vti6_net {
/* the vti6 tunnel fallback device */
struct net_device *fb_tnl_dev;
/* lists for storing tunnels in use */
struct ip6_tnl __rcu *tnls_r_l[HASH_SIZE];
struct ip6_tnl __rcu *tnls_wc[1];
struct ip6_tnl __rcu **tnls[2];
};
#define for_each_vti6_tunnel_rcu(start) \
for (t = rcu_dereference(start); t; t = rcu_dereference(t->next))
/**
* vti6_tnl_lookup - fetch tunnel matching the end-point addresses
* @net: network namespace
* @remote: the address of the tunnel exit-point
* @local: the address of the tunnel entry-point
*
* Return:
* tunnel matching given end-points if found,
* else fallback tunnel if its device is up,
* else %NULL
**/
static struct ip6_tnl *
vti6_tnl_lookup(struct net *net, const struct in6_addr *remote,
const struct in6_addr *local)
{
unsigned int hash = HASH(remote, local);
struct ip6_tnl *t;
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
struct in6_addr any;
for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
if (ipv6_addr_equal(local, &t->parms.laddr) &&
ipv6_addr_equal(remote, &t->parms.raddr) &&
(t->dev->flags & IFF_UP))
return t;
}
memset(&any, 0, sizeof(any));
hash = HASH(&any, local);
for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
if (ipv6_addr_equal(local, &t->parms.laddr) &&
(t->dev->flags & IFF_UP))
return t;
}
hash = HASH(remote, &any);
for_each_vti6_tunnel_rcu(ip6n->tnls_r_l[hash]) {
if (ipv6_addr_equal(remote, &t->parms.raddr) &&
(t->dev->flags & IFF_UP))
return t;
}
t = rcu_dereference(ip6n->tnls_wc[0]);
if (t && (t->dev->flags & IFF_UP))
return t;
return NULL;
}
/**
* vti6_tnl_bucket - get head of list matching given tunnel parameters
* @p: parameters containing tunnel end-points
*
* Description:
* vti6_tnl_bucket() returns the head of the list matching the
* &struct in6_addr entries laddr and raddr in @p.
*
* Return: head of IPv6 tunnel list
**/
static struct ip6_tnl __rcu **
vti6_tnl_bucket(struct vti6_net *ip6n, const struct __ip6_tnl_parm *p)
{
const struct in6_addr *remote = &p->raddr;
const struct in6_addr *local = &p->laddr;
unsigned int h = 0;
int prio = 0;
if (!ipv6_addr_any(remote) || !ipv6_addr_any(local)) {
prio = 1;
h = HASH(remote, local);
}
return &ip6n->tnls[prio][h];
}
static void
vti6_tnl_link(struct vti6_net *ip6n, struct ip6_tnl *t)
{
struct ip6_tnl __rcu **tp = vti6_tnl_bucket(ip6n, &t->parms);
rcu_assign_pointer(t->next , rtnl_dereference(*tp));
rcu_assign_pointer(*tp, t);
}
static void
vti6_tnl_unlink(struct vti6_net *ip6n, struct ip6_tnl *t)
{
struct ip6_tnl __rcu **tp;
struct ip6_tnl *iter;
for (tp = vti6_tnl_bucket(ip6n, &t->parms);
(iter = rtnl_dereference(*tp)) != NULL;
tp = &iter->next) {
if (t == iter) {
rcu_assign_pointer(*tp, t->next);
break;
}
}
}
static void vti6_dev_free(struct net_device *dev)
{
free_percpu(dev->tstats);
free_netdev(dev);
}
static int vti6_tnl_create2(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
struct net *net = dev_net(dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
int err;
err = register_netdevice(dev);
if (err < 0)
goto out;
strcpy(t->parms.name, dev->name);
dev->rtnl_link_ops = &vti6_link_ops;
dev_hold(dev);
vti6_tnl_link(ip6n, t);
return 0;
out:
return err;
}
static struct ip6_tnl *vti6_tnl_create(struct net *net, struct __ip6_tnl_parm *p)
{
struct net_device *dev;
struct ip6_tnl *t;
char name[IFNAMSIZ];
int err;
if (p->name[0])
strlcpy(name, p->name, IFNAMSIZ);
else
sprintf(name, "ip6_vti%%d");
dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN, vti6_dev_setup);
if (!dev)
goto failed;
dev_net_set(dev, net);
t = netdev_priv(dev);
t->parms = *p;
t->net = dev_net(dev);
err = vti6_tnl_create2(dev);
if (err < 0)
goto failed_free;
return t;
failed_free:
vti6_dev_free(dev);
failed:
return NULL;
}
/**
* vti6_locate - find or create tunnel matching given parameters
* @net: network namespace
* @p: tunnel parameters
* @create: != 0 if allowed to create new tunnel if no match found
*
* Description:
* vti6_locate() first tries to locate an existing tunnel
* based on @parms. If this is unsuccessful, but @create is set a new
* tunnel device is created and registered for use.
*
* Return:
* matching tunnel or NULL
**/
static struct ip6_tnl *vti6_locate(struct net *net, struct __ip6_tnl_parm *p,
int create)
{
const struct in6_addr *remote = &p->raddr;
const struct in6_addr *local = &p->laddr;
struct ip6_tnl __rcu **tp;
struct ip6_tnl *t;
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
for (tp = vti6_tnl_bucket(ip6n, p);
(t = rtnl_dereference(*tp)) != NULL;
tp = &t->next) {
if (ipv6_addr_equal(local, &t->parms.laddr) &&
ipv6_addr_equal(remote, &t->parms.raddr)) {
if (create)
return NULL;
return t;
}
}
if (!create)
return NULL;
return vti6_tnl_create(net, p);
}
/**
* vti6_dev_uninit - tunnel device uninitializer
* @dev: the device to be destroyed
*
* Description:
* vti6_dev_uninit() removes tunnel from its list
**/
static void vti6_dev_uninit(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
struct vti6_net *ip6n = net_generic(t->net, vti6_net_id);
if (dev == ip6n->fb_tnl_dev)
RCU_INIT_POINTER(ip6n->tnls_wc[0], NULL);
else
vti6_tnl_unlink(ip6n, t);
dev_put(dev);
}
static int vti6_rcv(struct sk_buff *skb)
{
struct ip6_tnl *t;
const struct ipv6hdr *ipv6h = ipv6_hdr(skb);
rcu_read_lock();
t = vti6_tnl_lookup(dev_net(skb->dev), &ipv6h->saddr, &ipv6h->daddr);
if (t) {
if (t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) {
rcu_read_unlock();
goto discard;
}
if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
rcu_read_unlock();
return 0;
}
if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
t->dev->stats.rx_dropped++;
rcu_read_unlock();
goto discard;
}
XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
rcu_read_unlock();
return xfrm6_rcv(skb);
}
rcu_read_unlock();
return -EINVAL;
discard:
kfree_skb(skb);
return 0;
}
static int vti6_rcv_cb(struct sk_buff *skb, int err)
{
unsigned short family;
struct net_device *dev;
struct pcpu_sw_netstats *tstats;
struct xfrm_state *x;
struct ip6_tnl *t = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6;
u32 orig_mark = skb->mark;
int ret;
if (!t)
return 1;
dev = t->dev;
if (err) {
dev->stats.rx_errors++;
dev->stats.rx_dropped++;
return 0;
}
x = xfrm_input_state(skb);
family = x->inner_mode->afinfo->family;
skb->mark = be32_to_cpu(t->parms.i_key);
ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family);
skb->mark = orig_mark;
if (!ret)
return -EPERM;
skb_scrub_packet(skb, !net_eq(t->net, dev_net(skb->dev)));
skb->dev = dev;
tstats = this_cpu_ptr(dev->tstats);
u64_stats_update_begin(&tstats->syncp);
tstats->rx_packets++;
tstats->rx_bytes += skb->len;
u64_stats_update_end(&tstats->syncp);
return 0;
}
/**
* vti6_addr_conflict - compare packet addresses to tunnel's own
* @t: the outgoing tunnel device
* @hdr: IPv6 header from the incoming packet
*
* Description:
* Avoid trivial tunneling loop by checking that tunnel exit-point
* doesn't match source of incoming packet.
*
* Return:
* 1 if conflict,
* 0 else
**/
static inline bool
vti6_addr_conflict(const struct ip6_tnl *t, const struct ipv6hdr *hdr)
{
return ipv6_addr_equal(&t->parms.raddr, &hdr->saddr);
}
static bool vti6_state_check(const struct xfrm_state *x,
const struct in6_addr *dst,
const struct in6_addr *src)
{
xfrm_address_t *daddr = (xfrm_address_t *)dst;
xfrm_address_t *saddr = (xfrm_address_t *)src;
/* if there is no transform then this tunnel is not functional.
* Or if the xfrm is not mode tunnel.
*/
if (!x || x->props.mode != XFRM_MODE_TUNNEL ||
x->props.family != AF_INET6)
return false;
if (ipv6_addr_any(dst))
return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET6);
if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET6))
return false;
return true;
}
/**
* vti6_xmit - send a packet
* @skb: the outgoing socket buffer
* @dev: the outgoing tunnel device
* @fl: the flow informations for the xfrm_lookup
**/
static int
vti6_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
{
struct ip6_tnl *t = netdev_priv(dev);
struct net_device_stats *stats = &t->dev->stats;
struct dst_entry *dst = skb_dst(skb);
struct net_device *tdev;
struct xfrm_state *x;
int err = -1;
int mtu;
if (!dst)
goto tx_err_link_failure;
dst_hold(dst);
dst = xfrm_lookup(t->net, dst, fl, NULL, 0);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
dst = NULL;
goto tx_err_link_failure;
}
x = dst->xfrm;
if (!vti6_state_check(x, &t->parms.raddr, &t->parms.laddr))
goto tx_err_link_failure;
if (!ip6_tnl_xmit_ctl(t, (const struct in6_addr *)&x->props.saddr,
(const struct in6_addr *)&x->id.daddr))
goto tx_err_link_failure;
tdev = dst->dev;
if (tdev == dev) {
stats->collisions++;
net_warn_ratelimited("%s: Local routing loop detected!\n",
t->parms.name);
goto tx_err_dst_release;
}
skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
mtu = dst_mtu(dst);
if (!skb->ignore_df && skb->len > mtu) {
skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu);
if (skb->protocol == htons(ETH_P_IPV6))
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
else
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
return -EMSGSIZE;
}
err = dst_output(skb);
if (net_xmit_eval(err) == 0) {
struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats);
u64_stats_update_begin(&tstats->syncp);
tstats->tx_bytes += skb->len;
tstats->tx_packets++;
u64_stats_update_end(&tstats->syncp);
} else {
stats->tx_errors++;
stats->tx_aborted_errors++;
}
return 0;
tx_err_link_failure:
stats->tx_carrier_errors++;
dst_link_failure(skb);
tx_err_dst_release:
dst_release(dst);
return err;
}
static netdev_tx_t
vti6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
struct net_device_stats *stats = &t->dev->stats;
struct ipv6hdr *ipv6h;
struct flowi fl;
int ret;
memset(&fl, 0, sizeof(fl));
switch (skb->protocol) {
case htons(ETH_P_IPV6):
ipv6h = ipv6_hdr(skb);
if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
vti6_addr_conflict(t, ipv6h))
goto tx_err;
xfrm_decode_session(skb, &fl, AF_INET6);
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
break;
case htons(ETH_P_IP):
xfrm_decode_session(skb, &fl, AF_INET);
memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
break;
default:
goto tx_err;
}
/* override mark with tunnel output key */
fl.flowi_mark = be32_to_cpu(t->parms.o_key);
ret = vti6_xmit(skb, dev, &fl);
if (ret < 0)
goto tx_err;
return NETDEV_TX_OK;
tx_err:
stats->tx_errors++;
stats->tx_dropped++;
kfree_skb(skb);
return NETDEV_TX_OK;
}
static int vti6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
__be32 spi;
__u32 mark;
struct xfrm_state *x;
struct ip6_tnl *t;
struct ip_esp_hdr *esph;
struct ip_auth_hdr *ah;
struct ip_comp_hdr *ipch;
struct net *net = dev_net(skb->dev);
const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
int protocol = iph->nexthdr;
t = vti6_tnl_lookup(dev_net(skb->dev), &iph->daddr, &iph->saddr);
if (!t)
return -1;
mark = be32_to_cpu(t->parms.o_key);
switch (protocol) {
case IPPROTO_ESP:
esph = (struct ip_esp_hdr *)(skb->data + offset);
spi = esph->spi;
break;
case IPPROTO_AH:
ah = (struct ip_auth_hdr *)(skb->data + offset);
spi = ah->spi;
break;
case IPPROTO_COMP:
ipch = (struct ip_comp_hdr *)(skb->data + offset);
spi = htonl(ntohs(ipch->cpi));
break;
default:
return 0;
}
if (type != ICMPV6_PKT_TOOBIG &&
type != NDISC_REDIRECT)
return 0;
x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr,
spi, protocol, AF_INET6);
if (!x)
return 0;
if (type == NDISC_REDIRECT)
ip6_redirect(skb, net, skb->dev->ifindex, 0);
else
ip6_update_pmtu(skb, net, info, 0, 0);
xfrm_state_put(x);
return 0;
}
static void vti6_link_config(struct ip6_tnl *t)
{
struct net_device *dev = t->dev;
struct __ip6_tnl_parm *p = &t->parms;
memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr));
memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr));
p->flags &= ~(IP6_TNL_F_CAP_XMIT | IP6_TNL_F_CAP_RCV |
IP6_TNL_F_CAP_PER_PACKET);
p->flags |= ip6_tnl_get_cap(t, &p->laddr, &p->raddr);
if (p->flags & IP6_TNL_F_CAP_XMIT && p->flags & IP6_TNL_F_CAP_RCV)
dev->flags |= IFF_POINTOPOINT;
else
dev->flags &= ~IFF_POINTOPOINT;
}
/**
* vti6_tnl_change - update the tunnel parameters
* @t: tunnel to be changed
* @p: tunnel configuration parameters
*
* Description:
* vti6_tnl_change() updates the tunnel parameters
**/
static int
vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p)
{
t->parms.laddr = p->laddr;
t->parms.raddr = p->raddr;
t->parms.link = p->link;
t->parms.i_key = p->i_key;
t->parms.o_key = p->o_key;
t->parms.proto = p->proto;
ip6_tnl_dst_reset(t);
vti6_link_config(t);
return 0;
}
static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p)
{
struct net *net = dev_net(t->dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
int err;
vti6_tnl_unlink(ip6n, t);
synchronize_net();
err = vti6_tnl_change(t, p);
vti6_tnl_link(ip6n, t);
netdev_state_change(t->dev);
return err;
}
static void
vti6_parm_from_user(struct __ip6_tnl_parm *p, const struct ip6_tnl_parm2 *u)
{
p->laddr = u->laddr;
p->raddr = u->raddr;
p->link = u->link;
p->i_key = u->i_key;
p->o_key = u->o_key;
p->proto = u->proto;
memcpy(p->name, u->name, sizeof(u->name));
}
static void
vti6_parm_to_user(struct ip6_tnl_parm2 *u, const struct __ip6_tnl_parm *p)
{
u->laddr = p->laddr;
u->raddr = p->raddr;
u->link = p->link;
u->i_key = p->i_key;
u->o_key = p->o_key;
u->proto = p->proto;
memcpy(u->name, p->name, sizeof(u->name));
}
/**
* vti6_tnl_ioctl - configure vti6 tunnels from userspace
* @dev: virtual device associated with tunnel
* @ifr: parameters passed from userspace
* @cmd: command to be performed
*
* Description:
* vti6_ioctl() is used for managing vti6 tunnels
* from userspace.
*
* The possible commands are the following:
* %SIOCGETTUNNEL: get tunnel parameters for device
* %SIOCADDTUNNEL: add tunnel matching given tunnel parameters
* %SIOCCHGTUNNEL: change tunnel parameters to those given
* %SIOCDELTUNNEL: delete tunnel
*
* The fallback device "ip6_vti0", created during module
* initialization, can be used for creating other tunnel devices.
*
* Return:
* 0 on success,
* %-EFAULT if unable to copy data to or from userspace,
* %-EPERM if current process hasn't %CAP_NET_ADMIN set
* %-EINVAL if passed tunnel parameters are invalid,
* %-EEXIST if changing a tunnel's parameters would cause a conflict
* %-ENODEV if attempting to change or delete a nonexisting device
**/
static int
vti6_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
int err = 0;
struct ip6_tnl_parm2 p;
struct __ip6_tnl_parm p1;
struct ip6_tnl *t = NULL;
struct net *net = dev_net(dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
switch (cmd) {
case SIOCGETTUNNEL:
if (dev == ip6n->fb_tnl_dev) {
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
err = -EFAULT;
break;
}
vti6_parm_from_user(&p1, &p);
t = vti6_locate(net, &p1, 0);
} else {
memset(&p, 0, sizeof(p));
}
if (!t)
t = netdev_priv(dev);
vti6_parm_to_user(&p, &t->parms);
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
err = -EFAULT;
break;
case SIOCADDTUNNEL:
case SIOCCHGTUNNEL:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
break;
err = -EFAULT;
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
break;
err = -EINVAL;
if (p.proto != IPPROTO_IPV6 && p.proto != 0)
break;
vti6_parm_from_user(&p1, &p);
t = vti6_locate(net, &p1, cmd == SIOCADDTUNNEL);
if (dev != ip6n->fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
if (t) {
if (t->dev != dev) {
err = -EEXIST;
break;
}
} else
t = netdev_priv(dev);
err = vti6_update(t, &p1);
}
if (t) {
err = 0;
vti6_parm_to_user(&p, &t->parms);
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
err = -EFAULT;
} else
err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
break;
case SIOCDELTUNNEL:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
break;
if (dev == ip6n->fb_tnl_dev) {
err = -EFAULT;
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
break;
err = -ENOENT;
vti6_parm_from_user(&p1, &p);
t = vti6_locate(net, &p1, 0);
if (!t)
break;
err = -EPERM;
if (t->dev == ip6n->fb_tnl_dev)
break;
dev = t->dev;
}
err = 0;
unregister_netdevice(dev);
break;
default:
err = -EINVAL;
}
return err;
}
/**
* vti6_tnl_change_mtu - change mtu manually for tunnel device
* @dev: virtual device associated with tunnel
* @new_mtu: the new mtu
*
* Return:
* 0 on success,
* %-EINVAL if mtu too small
**/
static int vti6_change_mtu(struct net_device *dev, int new_mtu)
{
if (new_mtu < IPV6_MIN_MTU)
return -EINVAL;
dev->mtu = new_mtu;
return 0;
}
static const struct net_device_ops vti6_netdev_ops = {
.ndo_init = vti6_dev_init,
.ndo_uninit = vti6_dev_uninit,
.ndo_start_xmit = vti6_tnl_xmit,
.ndo_do_ioctl = vti6_ioctl,
.ndo_change_mtu = vti6_change_mtu,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_get_iflink = ip6_tnl_get_iflink,
};
/**
* vti6_dev_setup - setup virtual tunnel device
* @dev: virtual device associated with tunnel
*
* Description:
* Initialize function pointers and device parameters
**/
static void vti6_dev_setup(struct net_device *dev)
{
dev->netdev_ops = &vti6_netdev_ops;
dev->destructor = vti6_dev_free;
dev->type = ARPHRD_TUNNEL6;
dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr);
dev->mtu = ETH_DATA_LEN;
dev->flags |= IFF_NOARP;
dev->addr_len = sizeof(struct in6_addr);
netif_keep_dst(dev);
}
/**
* vti6_dev_init_gen - general initializer for all tunnel devices
* @dev: virtual device associated with tunnel
**/
static inline int vti6_dev_init_gen(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
t->dev = dev;
t->net = dev_net(dev);
dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
if (!dev->tstats)
return -ENOMEM;
return 0;
}
/**
* vti6_dev_init - initializer for all non fallback tunnel devices
* @dev: virtual device associated with tunnel
**/
static int vti6_dev_init(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
int err = vti6_dev_init_gen(dev);
if (err)
return err;
vti6_link_config(t);
return 0;
}
/**
* vti6_fb_tnl_dev_init - initializer for fallback tunnel device
* @dev: fallback device
*
* Return: 0
**/
static int __net_init vti6_fb_tnl_dev_init(struct net_device *dev)
{
struct ip6_tnl *t = netdev_priv(dev);
struct net *net = dev_net(dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
t->parms.proto = IPPROTO_IPV6;
dev_hold(dev);
rcu_assign_pointer(ip6n->tnls_wc[0], t);
return 0;
}
static int vti6_validate(struct nlattr *tb[], struct nlattr *data[])
{
return 0;
}
static void vti6_netlink_parms(struct nlattr *data[],
struct __ip6_tnl_parm *parms)
{
memset(parms, 0, sizeof(*parms));
if (!data)
return;
if (data[IFLA_VTI_LINK])
parms->link = nla_get_u32(data[IFLA_VTI_LINK]);
if (data[IFLA_VTI_LOCAL])
parms->laddr = nla_get_in6_addr(data[IFLA_VTI_LOCAL]);
if (data[IFLA_VTI_REMOTE])
parms->raddr = nla_get_in6_addr(data[IFLA_VTI_REMOTE]);
if (data[IFLA_VTI_IKEY])
parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]);
if (data[IFLA_VTI_OKEY])
parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]);
}
static int vti6_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[])
{
struct net *net = dev_net(dev);
struct ip6_tnl *nt;
nt = netdev_priv(dev);
vti6_netlink_parms(data, &nt->parms);
nt->parms.proto = IPPROTO_IPV6;
if (vti6_locate(net, &nt->parms, 0))
return -EEXIST;
return vti6_tnl_create2(dev);
}
static void vti6_dellink(struct net_device *dev, struct list_head *head)
{
struct net *net = dev_net(dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
if (dev != ip6n->fb_tnl_dev)
unregister_netdevice_queue(dev, head);
}
static int vti6_changelink(struct net_device *dev, struct nlattr *tb[],
struct nlattr *data[])
{
struct ip6_tnl *t;
struct __ip6_tnl_parm p;
struct net *net = dev_net(dev);
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
if (dev == ip6n->fb_tnl_dev)
return -EINVAL;
vti6_netlink_parms(data, &p);
t = vti6_locate(net, &p, 0);
if (t) {
if (t->dev != dev)
return -EEXIST;
} else
t = netdev_priv(dev);
return vti6_update(t, &p);
}
static size_t vti6_get_size(const struct net_device *dev)
{
return
/* IFLA_VTI_LINK */
nla_total_size(4) +
/* IFLA_VTI_LOCAL */
nla_total_size(sizeof(struct in6_addr)) +
/* IFLA_VTI_REMOTE */
nla_total_size(sizeof(struct in6_addr)) +
/* IFLA_VTI_IKEY */
nla_total_size(4) +
/* IFLA_VTI_OKEY */
nla_total_size(4) +
0;
}
static int vti6_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct ip6_tnl *tunnel = netdev_priv(dev);
struct __ip6_tnl_parm *parm = &tunnel->parms;
if (nla_put_u32(skb, IFLA_VTI_LINK, parm->link) ||
nla_put_in6_addr(skb, IFLA_VTI_LOCAL, &parm->laddr) ||
nla_put_in6_addr(skb, IFLA_VTI_REMOTE, &parm->raddr) ||
nla_put_be32(skb, IFLA_VTI_IKEY, parm->i_key) ||
nla_put_be32(skb, IFLA_VTI_OKEY, parm->o_key))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static const struct nla_policy vti6_policy[IFLA_VTI_MAX + 1] = {
[IFLA_VTI_LINK] = { .type = NLA_U32 },
[IFLA_VTI_LOCAL] = { .len = sizeof(struct in6_addr) },
[IFLA_VTI_REMOTE] = { .len = sizeof(struct in6_addr) },
[IFLA_VTI_IKEY] = { .type = NLA_U32 },
[IFLA_VTI_OKEY] = { .type = NLA_U32 },
};
static struct rtnl_link_ops vti6_link_ops __read_mostly = {
.kind = "vti6",
.maxtype = IFLA_VTI_MAX,
.policy = vti6_policy,
.priv_size = sizeof(struct ip6_tnl),
.setup = vti6_dev_setup,
.validate = vti6_validate,
.newlink = vti6_newlink,
.dellink = vti6_dellink,
.changelink = vti6_changelink,
.get_size = vti6_get_size,
.fill_info = vti6_fill_info,
.get_link_net = ip6_tnl_get_link_net,
};
static void __net_exit vti6_destroy_tunnels(struct vti6_net *ip6n)
{
int h;
struct ip6_tnl *t;
LIST_HEAD(list);
for (h = 0; h < HASH_SIZE; h++) {
t = rtnl_dereference(ip6n->tnls_r_l[h]);
while (t) {
unregister_netdevice_queue(t->dev, &list);
t = rtnl_dereference(t->next);
}
}
t = rtnl_dereference(ip6n->tnls_wc[0]);
unregister_netdevice_queue(t->dev, &list);
unregister_netdevice_many(&list);
}
static int __net_init vti6_init_net(struct net *net)
{
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
struct ip6_tnl *t = NULL;
int err;
ip6n->tnls[0] = ip6n->tnls_wc;
ip6n->tnls[1] = ip6n->tnls_r_l;
err = -ENOMEM;
ip6n->fb_tnl_dev = alloc_netdev(sizeof(struct ip6_tnl), "ip6_vti0",
NET_NAME_UNKNOWN, vti6_dev_setup);
if (!ip6n->fb_tnl_dev)
goto err_alloc_dev;
dev_net_set(ip6n->fb_tnl_dev, net);
ip6n->fb_tnl_dev->rtnl_link_ops = &vti6_link_ops;
err = vti6_fb_tnl_dev_init(ip6n->fb_tnl_dev);
if (err < 0)
goto err_register;
err = register_netdev(ip6n->fb_tnl_dev);
if (err < 0)
goto err_register;
t = netdev_priv(ip6n->fb_tnl_dev);
strcpy(t->parms.name, ip6n->fb_tnl_dev->name);
return 0;
err_register:
vti6_dev_free(ip6n->fb_tnl_dev);
err_alloc_dev:
return err;
}
static void __net_exit vti6_exit_net(struct net *net)
{
struct vti6_net *ip6n = net_generic(net, vti6_net_id);
rtnl_lock();
vti6_destroy_tunnels(ip6n);
rtnl_unlock();
}
static struct pernet_operations vti6_net_ops = {
.init = vti6_init_net,
.exit = vti6_exit_net,
.id = &vti6_net_id,
.size = sizeof(struct vti6_net),
};
static struct xfrm6_protocol vti_esp6_protocol __read_mostly = {
.handler = vti6_rcv,
.cb_handler = vti6_rcv_cb,
.err_handler = vti6_err,
.priority = 100,
};
static struct xfrm6_protocol vti_ah6_protocol __read_mostly = {
.handler = vti6_rcv,
.cb_handler = vti6_rcv_cb,
.err_handler = vti6_err,
.priority = 100,
};
static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = {
.handler = vti6_rcv,
.cb_handler = vti6_rcv_cb,
.err_handler = vti6_err,
.priority = 100,
};
/**
* vti6_tunnel_init - register protocol and reserve needed resources
*
* Return: 0 on success
**/
static int __init vti6_tunnel_init(void)
{
const char *msg;
int err;
msg = "tunnel device";
err = register_pernet_device(&vti6_net_ops);
if (err < 0)
goto pernet_dev_failed;
msg = "tunnel protocols";
err = xfrm6_protocol_register(&vti_esp6_protocol, IPPROTO_ESP);
if (err < 0)
goto xfrm_proto_esp_failed;
err = xfrm6_protocol_register(&vti_ah6_protocol, IPPROTO_AH);
if (err < 0)
goto xfrm_proto_ah_failed;
err = xfrm6_protocol_register(&vti_ipcomp6_protocol, IPPROTO_COMP);
if (err < 0)
goto xfrm_proto_comp_failed;
msg = "netlink interface";
err = rtnl_link_register(&vti6_link_ops);
if (err < 0)
goto rtnl_link_failed;
return 0;
rtnl_link_failed:
xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
xfrm_proto_comp_failed:
xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
xfrm_proto_ah_failed:
xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
xfrm_proto_esp_failed:
unregister_pernet_device(&vti6_net_ops);
pernet_dev_failed:
pr_err("vti6 init: failed to register %s\n", msg);
return err;
}
/**
* vti6_tunnel_cleanup - free resources and unregister protocol
**/
static void __exit vti6_tunnel_cleanup(void)
{
rtnl_link_unregister(&vti6_link_ops);
xfrm6_protocol_deregister(&vti_ipcomp6_protocol, IPPROTO_COMP);
xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH);
xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP);
unregister_pernet_device(&vti6_net_ops);
}
module_init(vti6_tunnel_init);
module_exit(vti6_tunnel_cleanup);
MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("vti6");
MODULE_ALIAS_NETDEV("ip6_vti0");
MODULE_AUTHOR("Steffen Klassert");
MODULE_DESCRIPTION("IPv6 virtual tunnel interface");