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ip6_vti.c
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ip6_vti.c
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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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
*/
#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>
#include <linux/etherdevice.h>
#define IP6_VTI_HASH_SIZE_SHIFT 5
#define IP6_VTI_HASH_SIZE (1 << IP6_VTI_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, IP6_VTI_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 unsigned 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[IP6_VTI_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
* @ip6n: the private data for ip6_vti in the netns
* @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);
}
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;
dev->rtnl_link_ops = &vti6_link_ops;
err = register_netdevice(dev);
if (err < 0)
goto out;
strcpy(t->parms.name, dev->name);
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]) {
if (!dev_valid_name(p->name))
goto failed;
strscpy(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:
free_netdev(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);
netdev_put(dev, &t->dev_tracker);
}
static int vti6_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi,
int encap_type)
{
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();
goto discard;
}
ipv6h = ipv6_hdr(skb);
if (!ip6_tnl_rcv_ctl(t, &ipv6h->daddr, &ipv6h->saddr)) {
t->dev->stats.rx_dropped++;
rcu_read_unlock();
goto discard;
}
rcu_read_unlock();
XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
return xfrm_input(skb, nexthdr, spi, encap_type);
}
rcu_read_unlock();
return -EINVAL;
discard:
kfree_skb(skb);
return 0;
}
static int vti6_rcv(struct sk_buff *skb)
{
int nexthdr = skb_network_header(skb)[IP6CB(skb)->nhoff];
return vti6_input_proto(skb, nexthdr, 0, 0);
}
static int vti6_rcv_cb(struct sk_buff *skb, int err)
{
unsigned short family;
struct net_device *dev;
struct xfrm_state *x;
const struct xfrm_mode *inner_mode;
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);
inner_mode = &x->inner_mode;
if (x->sel.family == AF_UNSPEC) {
inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
if (inner_mode == NULL) {
XFRM_INC_STATS(dev_net(skb->dev),
LINUX_MIB_XFRMINSTATEMODEERROR);
return -EINVAL;
}
}
family = inner_mode->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;
dev_sw_netstats_rx_add(dev, skb->len);
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 pkt_len = skb->len;
int err = -1;
int mtu;
if (!dst) {
switch (skb->protocol) {
case htons(ETH_P_IP): {
struct rtable *rt;
fl->u.ip4.flowi4_oif = dev->ifindex;
fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC;
rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4);
if (IS_ERR(rt))
goto tx_err_link_failure;
dst = &rt->dst;
skb_dst_set(skb, dst);
break;
}
case htons(ETH_P_IPV6):
fl->u.ip6.flowi6_oif = dev->ifindex;
fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC;
dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6);
if (dst->error) {
dst_release(dst);
dst = NULL;
goto tx_err_link_failure;
}
skb_dst_set(skb, dst);
break;
default:
goto tx_err_link_failure;
}
}
dst_hold(dst);
dst = xfrm_lookup_route(t->net, dst, fl, NULL, 0);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
dst = NULL;
goto tx_err_link_failure;
}
if (dst->flags & DST_XFRM_QUEUE)
goto xmit;
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;
}
mtu = dst_mtu(dst);
if (skb->len > mtu) {
skb_dst_update_pmtu_no_confirm(skb, mtu);
if (skb->protocol == htons(ETH_P_IPV6)) {
if (mtu < IPV6_MIN_MTU)
mtu = IPV6_MIN_MTU;
icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
} else {
if (!(ip_hdr(skb)->frag_off & htons(IP_DF)))
goto xmit;
icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
}
err = -EMSGSIZE;
goto tx_err_dst_release;
}
xmit:
skb_scrub_packet(skb, !net_eq(t->net, dev_net(dev)));
skb_dst_set(skb, dst);
skb->dev = skb_dst(skb)->dev;
err = dst_output(t->net, skb->sk, skb);
if (net_xmit_eval(err) == 0)
err = pkt_len;
iptunnel_xmit_stats(dev, err);
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 flowi fl;
int ret;
if (!pskb_inet_may_pull(skb))
goto tx_err;
memset(&fl, 0, sizeof(fl));
switch (skb->protocol) {
case htons(ETH_P_IPV6):
if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
vti6_addr_conflict(t, ipv6_hdr(skb)))
goto tx_err;
memset(IP6CB(skb), 0, sizeof(*IP6CB(skb)));
xfrm_decode_session(skb, &fl, AF_INET6);
break;
case htons(ETH_P_IP):
memset(IPCB(skb), 0, sizeof(*IPCB(skb)));
xfrm_decode_session(skb, &fl, AF_INET);
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,
sock_net_uid(net, NULL));
else
ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
xfrm_state_put(x);
return 0;
}
static void vti6_link_config(struct ip6_tnl *t, bool keep_mtu)
{
struct net_device *dev = t->dev;
struct __ip6_tnl_parm *p = &t->parms;
struct net_device *tdev = NULL;
int mtu;
__dev_addr_set(dev, &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;
if (keep_mtu && dev->mtu) {
dev->mtu = clamp(dev->mtu, dev->min_mtu, dev->max_mtu);
return;
}
if (p->flags & IP6_TNL_F_CAP_XMIT) {
int strict = (ipv6_addr_type(&p->raddr) &
(IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL));
struct rt6_info *rt = rt6_lookup(t->net,
&p->raddr, &p->laddr,
p->link, NULL, strict);
if (rt)
tdev = rt->dst.dev;
ip6_rt_put(rt);
}
if (!tdev && p->link)
tdev = __dev_get_by_index(t->net, p->link);
if (tdev)
mtu = tdev->mtu - sizeof(struct ipv6hdr);
else
mtu = ETH_DATA_LEN - LL_MAX_HEADER - sizeof(struct ipv6hdr);
dev->mtu = max_t(int, mtu, IPV4_MIN_MTU);
}
/**
* vti6_tnl_change - update the tunnel parameters
* @t: tunnel to be changed
* @p: tunnel configuration parameters
* @keep_mtu: MTU was set from userspace, don't re-compute it
*
* Description:
* vti6_tnl_change() updates the tunnel parameters
**/
static int
vti6_tnl_change(struct ip6_tnl *t, const struct __ip6_tnl_parm *p,
bool keep_mtu)
{
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;
t->parms.fwmark = p->fwmark;
dst_cache_reset(&t->dst_cache);
vti6_link_config(t, keep_mtu);
return 0;
}
static int vti6_update(struct ip6_tnl *t, struct __ip6_tnl_parm *p,
bool keep_mtu)
{
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, keep_mtu);
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;
if (u->i_key)
u->i_flags |= GRE_KEY;
if (u->o_key)
u->o_flags |= GRE_KEY;
u->proto = p->proto;
memcpy(u->name, p->name, sizeof(u->name));
}
/**
* vti6_siocdevprivate - configure vti6 tunnels from userspace
* @dev: virtual device associated with tunnel
* @ifr: unused
* @data: parameters passed from userspace
* @cmd: command to be performed
*
* Description:
* vti6_siocdevprivate() 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_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, 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);
memset(&p1, 0, sizeof(p1));
switch (cmd) {
case SIOCGETTUNNEL:
if (dev == ip6n->fb_tnl_dev) {
if (copy_from_user(&p, 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(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, 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, false);
}
if (t) {
err = 0;
vti6_parm_to_user(&p, &t->parms);
if (copy_to_user(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, 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;
}
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_siocdevprivate = vti6_siocdevprivate,
.ndo_get_stats64 = dev_get_tstats64,
.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->header_ops = &ip_tunnel_header_ops;
dev->needs_free_netdev = true;
dev->priv_destructor = vti6_dev_free;
dev->type = ARPHRD_TUNNEL6;
dev->min_mtu = IPV4_MIN_MTU;
dev->max_mtu = IP_MAX_MTU - sizeof(struct ipv6hdr);
dev->flags |= IFF_NOARP;
dev->addr_len = sizeof(struct in6_addr);
netif_keep_dst(dev);
/* This perm addr will be used as interface identifier by IPv6 */
dev->addr_assign_type = NET_ADDR_RANDOM;
eth_random_addr(dev->perm_addr);
}
/**
* 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;
netdev_hold(dev, &t->dev_tracker, GFP_KERNEL);
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, true);
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;
rcu_assign_pointer(ip6n->tnls_wc[0], t);
return 0;
}
static int vti6_validate(struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
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]);