swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 79a3aaa7b82e3106be97842dedfd8429248896e6 authored by Linus Torvalds on 31 March 2019, 21:39:29 UTC
Linux 5.1-rc3
Linux 5.1-rc3
Tip revision: 79a3aaa
sit.c
/*
* IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT)
* Linux INET6 implementation
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
* Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
*
* 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.
*
* Changes:
* Roger Venning <r.venning@telstra.com>: 6to4 support
* Nate Thompson <nate@thebog.net>: 6to4 support
* Fred Templin <fred.l.templin@boeing.com>: isatap support
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/icmp.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/init.h>
#include <linux/netfilter_ipv4.h>
#include <linux/if_ether.h>
#include <net/sock.h>
#include <net/snmp.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/transp_v6.h>
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/ip.h>
#include <net/udp.h>
#include <net/icmp.h>
#include <net/ip_tunnels.h>
#include <net/inet_ecn.h>
#include <net/xfrm.h>
#include <net/dsfield.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
/*
This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c
For comments look at net/ipv4/ip_gre.c --ANK
*/
#define IP6_SIT_HASH_SIZE 16
#define HASH(addr) (((__force u32)addr^((__force u32)addr>>4))&0xF)
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");
static int ipip6_tunnel_init(struct net_device *dev);
static void ipip6_tunnel_setup(struct net_device *dev);
static void ipip6_dev_free(struct net_device *dev);
static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
__be32 *v4dst);
static struct rtnl_link_ops sit_link_ops __read_mostly;
static unsigned int sit_net_id __read_mostly;
struct sit_net {
struct ip_tunnel __rcu *tunnels_r_l[IP6_SIT_HASH_SIZE];
struct ip_tunnel __rcu *tunnels_r[IP6_SIT_HASH_SIZE];
struct ip_tunnel __rcu *tunnels_l[IP6_SIT_HASH_SIZE];
struct ip_tunnel __rcu *tunnels_wc[1];
struct ip_tunnel __rcu **tunnels[4];
struct net_device *fb_tunnel_dev;
};
/*
* Must be invoked with rcu_read_lock
*/
static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net,
struct net_device *dev,
__be32 remote, __be32 local,
int sifindex)
{
unsigned int h0 = HASH(remote);
unsigned int h1 = HASH(local);
struct ip_tunnel *t;
struct sit_net *sitn = net_generic(net, sit_net_id);
int ifindex = dev ? dev->ifindex : 0;
for_each_ip_tunnel_rcu(t, sitn->tunnels_r_l[h0 ^ h1]) {
if (local == t->parms.iph.saddr &&
remote == t->parms.iph.daddr &&
(!dev || !t->parms.link || ifindex == t->parms.link ||
sifindex == t->parms.link) &&
(t->dev->flags & IFF_UP))
return t;
}
for_each_ip_tunnel_rcu(t, sitn->tunnels_r[h0]) {
if (remote == t->parms.iph.daddr &&
(!dev || !t->parms.link || ifindex == t->parms.link ||
sifindex == t->parms.link) &&
(t->dev->flags & IFF_UP))
return t;
}
for_each_ip_tunnel_rcu(t, sitn->tunnels_l[h1]) {
if (local == t->parms.iph.saddr &&
(!dev || !t->parms.link || ifindex == t->parms.link ||
sifindex == t->parms.link) &&
(t->dev->flags & IFF_UP))
return t;
}
t = rcu_dereference(sitn->tunnels_wc[0]);
if (t && (t->dev->flags & IFF_UP))
return t;
return NULL;
}
static struct ip_tunnel __rcu **__ipip6_bucket(struct sit_net *sitn,
struct ip_tunnel_parm *parms)
{
__be32 remote = parms->iph.daddr;
__be32 local = parms->iph.saddr;
unsigned int h = 0;
int prio = 0;
if (remote) {
prio |= 2;
h ^= HASH(remote);
}
if (local) {
prio |= 1;
h ^= HASH(local);
}
return &sitn->tunnels[prio][h];
}
static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn,
struct ip_tunnel *t)
{
return __ipip6_bucket(sitn, &t->parms);
}
static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t)
{
struct ip_tunnel __rcu **tp;
struct ip_tunnel *iter;
for (tp = ipip6_bucket(sitn, t);
(iter = rtnl_dereference(*tp)) != NULL;
tp = &iter->next) {
if (t == iter) {
rcu_assign_pointer(*tp, t->next);
break;
}
}
}
static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t)
{
struct ip_tunnel __rcu **tp = ipip6_bucket(sitn, t);
rcu_assign_pointer(t->next, rtnl_dereference(*tp));
rcu_assign_pointer(*tp, t);
}
static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn)
{
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel *t = netdev_priv(dev);
if (dev == sitn->fb_tunnel_dev || !sitn->fb_tunnel_dev) {
ipv6_addr_set(&t->ip6rd.prefix, htonl(0x20020000), 0, 0, 0);
t->ip6rd.relay_prefix = 0;
t->ip6rd.prefixlen = 16;
t->ip6rd.relay_prefixlen = 0;
} else {
struct ip_tunnel *t0 = netdev_priv(sitn->fb_tunnel_dev);
memcpy(&t->ip6rd, &t0->ip6rd, sizeof(t->ip6rd));
}
#endif
}
static int ipip6_tunnel_create(struct net_device *dev)
{
struct ip_tunnel *t = netdev_priv(dev);
struct net *net = dev_net(dev);
struct sit_net *sitn = net_generic(net, sit_net_id);
int err;
memcpy(dev->dev_addr, &t->parms.iph.saddr, 4);
memcpy(dev->broadcast, &t->parms.iph.daddr, 4);
if ((__force u16)t->parms.i_flags & SIT_ISATAP)
dev->priv_flags |= IFF_ISATAP;
dev->rtnl_link_ops = &sit_link_ops;
err = register_netdevice(dev);
if (err < 0)
goto out;
ipip6_tunnel_clone_6rd(dev, sitn);
dev_hold(dev);
ipip6_tunnel_link(sitn, t);
return 0;
out:
return err;
}
static struct ip_tunnel *ipip6_tunnel_locate(struct net *net,
struct ip_tunnel_parm *parms, int create)
{
__be32 remote = parms->iph.daddr;
__be32 local = parms->iph.saddr;
struct ip_tunnel *t, *nt;
struct ip_tunnel __rcu **tp;
struct net_device *dev;
char name[IFNAMSIZ];
struct sit_net *sitn = net_generic(net, sit_net_id);
for (tp = __ipip6_bucket(sitn, parms);
(t = rtnl_dereference(*tp)) != NULL;
tp = &t->next) {
if (local == t->parms.iph.saddr &&
remote == t->parms.iph.daddr &&
parms->link == t->parms.link) {
if (create)
return NULL;
else
return t;
}
}
if (!create)
goto failed;
if (parms->name[0]) {
if (!dev_valid_name(parms->name))
goto failed;
strlcpy(name, parms->name, IFNAMSIZ);
} else {
strcpy(name, "sit%d");
}
dev = alloc_netdev(sizeof(*t), name, NET_NAME_UNKNOWN,
ipip6_tunnel_setup);
if (!dev)
return NULL;
dev_net_set(dev, net);
nt = netdev_priv(dev);
nt->parms = *parms;
if (ipip6_tunnel_create(dev) < 0)
goto failed_free;
return nt;
failed_free:
free_netdev(dev);
failed:
return NULL;
}
#define for_each_prl_rcu(start) \
for (prl = rcu_dereference(start); \
prl; \
prl = rcu_dereference(prl->next))
static struct ip_tunnel_prl_entry *
__ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr)
{
struct ip_tunnel_prl_entry *prl;
for_each_prl_rcu(t->prl)
if (prl->addr == addr)
break;
return prl;
}
static int ipip6_tunnel_get_prl(struct ip_tunnel *t,
struct ip_tunnel_prl __user *a)
{
struct ip_tunnel_prl kprl, *kp;
struct ip_tunnel_prl_entry *prl;
unsigned int cmax, c = 0, ca, len;
int ret = 0;
if (copy_from_user(&kprl, a, sizeof(kprl)))
return -EFAULT;
cmax = kprl.datalen / sizeof(kprl);
if (cmax > 1 && kprl.addr != htonl(INADDR_ANY))
cmax = 1;
/* For simple GET or for root users,
* we try harder to allocate.
*/
kp = (cmax <= 1 || capable(CAP_NET_ADMIN)) ?
kcalloc(cmax, sizeof(*kp), GFP_KERNEL | __GFP_NOWARN) :
NULL;
rcu_read_lock();
ca = t->prl_count < cmax ? t->prl_count : cmax;
if (!kp) {
/* We don't try hard to allocate much memory for
* non-root users.
* For root users, retry allocating enough memory for
* the answer.
*/
kp = kcalloc(ca, sizeof(*kp), GFP_ATOMIC);
if (!kp) {
ret = -ENOMEM;
goto out;
}
}
c = 0;
for_each_prl_rcu(t->prl) {
if (c >= cmax)
break;
if (kprl.addr != htonl(INADDR_ANY) && prl->addr != kprl.addr)
continue;
kp[c].addr = prl->addr;
kp[c].flags = prl->flags;
c++;
if (kprl.addr != htonl(INADDR_ANY))
break;
}
out:
rcu_read_unlock();
len = sizeof(*kp) * c;
ret = 0;
if ((len && copy_to_user(a + 1, kp, len)) || put_user(len, &a->datalen))
ret = -EFAULT;
kfree(kp);
return ret;
}
static int
ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg)
{
struct ip_tunnel_prl_entry *p;
int err = 0;
if (a->addr == htonl(INADDR_ANY))
return -EINVAL;
ASSERT_RTNL();
for (p = rtnl_dereference(t->prl); p; p = rtnl_dereference(p->next)) {
if (p->addr == a->addr) {
if (chg) {
p->flags = a->flags;
goto out;
}
err = -EEXIST;
goto out;
}
}
if (chg) {
err = -ENXIO;
goto out;
}
p = kzalloc(sizeof(struct ip_tunnel_prl_entry), GFP_KERNEL);
if (!p) {
err = -ENOBUFS;
goto out;
}
p->next = t->prl;
p->addr = a->addr;
p->flags = a->flags;
t->prl_count++;
rcu_assign_pointer(t->prl, p);
out:
return err;
}
static void prl_list_destroy_rcu(struct rcu_head *head)
{
struct ip_tunnel_prl_entry *p, *n;
p = container_of(head, struct ip_tunnel_prl_entry, rcu_head);
do {
n = rcu_dereference_protected(p->next, 1);
kfree(p);
p = n;
} while (p);
}
static int
ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a)
{
struct ip_tunnel_prl_entry *x;
struct ip_tunnel_prl_entry __rcu **p;
int err = 0;
ASSERT_RTNL();
if (a && a->addr != htonl(INADDR_ANY)) {
for (p = &t->prl;
(x = rtnl_dereference(*p)) != NULL;
p = &x->next) {
if (x->addr == a->addr) {
*p = x->next;
kfree_rcu(x, rcu_head);
t->prl_count--;
goto out;
}
}
err = -ENXIO;
} else {
x = rtnl_dereference(t->prl);
if (x) {
t->prl_count = 0;
call_rcu(&x->rcu_head, prl_list_destroy_rcu);
t->prl = NULL;
}
}
out:
return err;
}
static int
isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t)
{
struct ip_tunnel_prl_entry *p;
int ok = 1;
rcu_read_lock();
p = __ipip6_tunnel_locate_prl(t, iph->saddr);
if (p) {
if (p->flags & PRL_DEFAULT)
skb->ndisc_nodetype = NDISC_NODETYPE_DEFAULT;
else
skb->ndisc_nodetype = NDISC_NODETYPE_NODEFAULT;
} else {
const struct in6_addr *addr6 = &ipv6_hdr(skb)->saddr;
if (ipv6_addr_is_isatap(addr6) &&
(addr6->s6_addr32[3] == iph->saddr) &&
ipv6_chk_prefix(addr6, t->dev))
skb->ndisc_nodetype = NDISC_NODETYPE_HOST;
else
ok = 0;
}
rcu_read_unlock();
return ok;
}
static void ipip6_tunnel_uninit(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
struct sit_net *sitn = net_generic(tunnel->net, sit_net_id);
if (dev == sitn->fb_tunnel_dev) {
RCU_INIT_POINTER(sitn->tunnels_wc[0], NULL);
} else {
ipip6_tunnel_unlink(sitn, tunnel);
ipip6_tunnel_del_prl(tunnel, NULL);
}
dst_cache_reset(&tunnel->dst_cache);
dev_put(dev);
}
static int ipip6_err(struct sk_buff *skb, u32 info)
{
const struct iphdr *iph = (const struct iphdr *)skb->data;
const int type = icmp_hdr(skb)->type;
const int code = icmp_hdr(skb)->code;
unsigned int data_len = 0;
struct ip_tunnel *t;
int sifindex;
int err;
switch (type) {
default:
case ICMP_PARAMETERPROB:
return 0;
case ICMP_DEST_UNREACH:
switch (code) {
case ICMP_SR_FAILED:
/* Impossible event. */
return 0;
default:
/* All others are translated to HOST_UNREACH.
rfc2003 contains "deep thoughts" about NET_UNREACH,
I believe they are just ether pollution. --ANK
*/
break;
}
break;
case ICMP_TIME_EXCEEDED:
if (code != ICMP_EXC_TTL)
return 0;
data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */
break;
case ICMP_REDIRECT:
break;
}
err = -ENOENT;
sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0;
t = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
iph->daddr, iph->saddr, sifindex);
if (!t)
goto out;
if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
ipv4_update_pmtu(skb, dev_net(skb->dev), info,
t->parms.link, iph->protocol);
err = 0;
goto out;
}
if (type == ICMP_REDIRECT) {
ipv4_redirect(skb, dev_net(skb->dev), t->parms.link,
iph->protocol);
err = 0;
goto out;
}
err = 0;
if (__in6_dev_get(skb->dev) &&
!ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4, type, data_len))
goto out;
if (t->parms.iph.daddr == 0)
goto out;
if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
goto out;
if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO))
t->err_count++;
else
t->err_count = 1;
t->err_time = jiffies;
out:
return err;
}
static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr,
const struct in6_addr *v6addr)
{
__be32 v4embed = 0;
if (check_6rd(tunnel, v6addr, &v4embed) && v4addr != v4embed)
return true;
return false;
}
/* Checks if an address matches an address on the tunnel interface.
* Used to detect the NAT of proto 41 packets and let them pass spoofing test.
* Long story:
* This function is called after we considered the packet as spoofed
* in is_spoofed_6rd.
* We may have a router that is doing NAT for proto 41 packets
* for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb
* will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd
* function will return true, dropping the packet.
* But, we can still check if is spoofed against the IP
* addresses associated with the interface.
*/
static bool only_dnatted(const struct ip_tunnel *tunnel,
const struct in6_addr *v6dst)
{
int prefix_len;
#ifdef CONFIG_IPV6_SIT_6RD
prefix_len = tunnel->ip6rd.prefixlen + 32
- tunnel->ip6rd.relay_prefixlen;
#else
prefix_len = 48;
#endif
return ipv6_chk_custom_prefix(v6dst, prefix_len, tunnel->dev);
}
/* Returns true if a packet is spoofed */
static bool packet_is_spoofed(struct sk_buff *skb,
const struct iphdr *iph,
struct ip_tunnel *tunnel)
{
const struct ipv6hdr *ipv6h;
if (tunnel->dev->priv_flags & IFF_ISATAP) {
if (!isatap_chksrc(skb, iph, tunnel))
return true;
return false;
}
if (tunnel->dev->flags & IFF_POINTOPOINT)
return false;
ipv6h = ipv6_hdr(skb);
if (unlikely(is_spoofed_6rd(tunnel, iph->saddr, &ipv6h->saddr))) {
net_warn_ratelimited("Src spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
&iph->saddr, &ipv6h->saddr,
&iph->daddr, &ipv6h->daddr);
return true;
}
if (likely(!is_spoofed_6rd(tunnel, iph->daddr, &ipv6h->daddr)))
return false;
if (only_dnatted(tunnel, &ipv6h->daddr))
return false;
net_warn_ratelimited("Dst spoofed %pI4/%pI6c -> %pI4/%pI6c\n",
&iph->saddr, &ipv6h->saddr,
&iph->daddr, &ipv6h->daddr);
return true;
}
static int ipip6_rcv(struct sk_buff *skb)
{
const struct iphdr *iph = ip_hdr(skb);
struct ip_tunnel *tunnel;
int sifindex;
int err;
sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0;
tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
iph->saddr, iph->daddr, sifindex);
if (tunnel) {
struct pcpu_sw_netstats *tstats;
if (tunnel->parms.iph.protocol != IPPROTO_IPV6 &&
tunnel->parms.iph.protocol != 0)
goto out;
skb->mac_header = skb->network_header;
skb_reset_network_header(skb);
IPCB(skb)->flags = 0;
skb->dev = tunnel->dev;
if (packet_is_spoofed(skb, iph, tunnel)) {
tunnel->dev->stats.rx_errors++;
goto out;
}
if (iptunnel_pull_header(skb, 0, htons(ETH_P_IPV6),
!net_eq(tunnel->net, dev_net(tunnel->dev))))
goto out;
err = IP_ECN_decapsulate(iph, skb);
if (unlikely(err)) {
if (log_ecn_error)
net_info_ratelimited("non-ECT from %pI4 with TOS=%#x\n",
&iph->saddr, iph->tos);
if (err > 1) {
++tunnel->dev->stats.rx_frame_errors;
++tunnel->dev->stats.rx_errors;
goto out;
}
}
tstats = this_cpu_ptr(tunnel->dev->tstats);
u64_stats_update_begin(&tstats->syncp);
tstats->rx_packets++;
tstats->rx_bytes += skb->len;
u64_stats_update_end(&tstats->syncp);
netif_rx(skb);
return 0;
}
/* no tunnel matched, let upstream know, ipsec may handle it */
return 1;
out:
kfree_skb(skb);
return 0;
}
static const struct tnl_ptk_info ipip_tpi = {
/* no tunnel info required for ipip. */
.proto = htons(ETH_P_IP),
};
#if IS_ENABLED(CONFIG_MPLS)
static const struct tnl_ptk_info mplsip_tpi = {
/* no tunnel info required for mplsip. */
.proto = htons(ETH_P_MPLS_UC),
};
#endif
static int sit_tunnel_rcv(struct sk_buff *skb, u8 ipproto)
{
const struct iphdr *iph;
struct ip_tunnel *tunnel;
int sifindex;
sifindex = netif_is_l3_master(skb->dev) ? IPCB(skb)->iif : 0;
iph = ip_hdr(skb);
tunnel = ipip6_tunnel_lookup(dev_net(skb->dev), skb->dev,
iph->saddr, iph->daddr, sifindex);
if (tunnel) {
const struct tnl_ptk_info *tpi;
if (tunnel->parms.iph.protocol != ipproto &&
tunnel->parms.iph.protocol != 0)
goto drop;
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
goto drop;
#if IS_ENABLED(CONFIG_MPLS)
if (ipproto == IPPROTO_MPLS)
tpi = &mplsip_tpi;
else
#endif
tpi = &ipip_tpi;
if (iptunnel_pull_header(skb, 0, tpi->proto, false))
goto drop;
return ip_tunnel_rcv(tunnel, skb, tpi, NULL, log_ecn_error);
}
return 1;
drop:
kfree_skb(skb);
return 0;
}
static int ipip_rcv(struct sk_buff *skb)
{
return sit_tunnel_rcv(skb, IPPROTO_IPIP);
}
#if IS_ENABLED(CONFIG_MPLS)
static int mplsip_rcv(struct sk_buff *skb)
{
return sit_tunnel_rcv(skb, IPPROTO_MPLS);
}
#endif
/*
* If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function
* stores the embedded IPv4 address in v4dst and returns true.
*/
static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst,
__be32 *v4dst)
{
#ifdef CONFIG_IPV6_SIT_6RD
if (ipv6_prefix_equal(v6dst, &tunnel->ip6rd.prefix,
tunnel->ip6rd.prefixlen)) {
unsigned int pbw0, pbi0;
int pbi1;
u32 d;
pbw0 = tunnel->ip6rd.prefixlen >> 5;
pbi0 = tunnel->ip6rd.prefixlen & 0x1f;
d = tunnel->ip6rd.relay_prefixlen < 32 ?
(ntohl(v6dst->s6_addr32[pbw0]) << pbi0) >>
tunnel->ip6rd.relay_prefixlen : 0;
pbi1 = pbi0 - tunnel->ip6rd.relay_prefixlen;
if (pbi1 > 0)
d |= ntohl(v6dst->s6_addr32[pbw0 + 1]) >>
(32 - pbi1);
*v4dst = tunnel->ip6rd.relay_prefix | htonl(d);
return true;
}
#else
if (v6dst->s6_addr16[0] == htons(0x2002)) {
/* 6to4 v6 addr has 16 bits prefix, 32 v4addr, 16 SLA, ... */
memcpy(v4dst, &v6dst->s6_addr16[1], 4);
return true;
}
#endif
return false;
}
static inline __be32 try_6rd(struct ip_tunnel *tunnel,
const struct in6_addr *v6dst)
{
__be32 dst = 0;
check_6rd(tunnel, v6dst, &dst);
return dst;
}
/*
* This function assumes it is being called from dev_queue_xmit()
* and that skb is filled properly by that function.
*/
static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb,
struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
const struct iphdr *tiph = &tunnel->parms.iph;
const struct ipv6hdr *iph6 = ipv6_hdr(skb);
u8 tos = tunnel->parms.iph.tos;
__be16 df = tiph->frag_off;
struct rtable *rt; /* Route to the other host */
struct net_device *tdev; /* Device to other host */
unsigned int max_headroom; /* The extra header space needed */
__be32 dst = tiph->daddr;
struct flowi4 fl4;
int mtu;
const struct in6_addr *addr6;
int addr_type;
u8 ttl;
u8 protocol = IPPROTO_IPV6;
int t_hlen = tunnel->hlen + sizeof(struct iphdr);
if (tos == 1)
tos = ipv6_get_dsfield(iph6);
/* ISATAP (RFC4214) - must come before 6to4 */
if (dev->priv_flags & IFF_ISATAP) {
struct neighbour *neigh = NULL;
bool do_tx_error = false;
if (skb_dst(skb))
neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
if (!neigh) {
net_dbg_ratelimited("nexthop == NULL\n");
goto tx_error;
}
addr6 = (const struct in6_addr *)&neigh->primary_key;
addr_type = ipv6_addr_type(addr6);
if ((addr_type & IPV6_ADDR_UNICAST) &&
ipv6_addr_is_isatap(addr6))
dst = addr6->s6_addr32[3];
else
do_tx_error = true;
neigh_release(neigh);
if (do_tx_error)
goto tx_error;
}
if (!dst)
dst = try_6rd(tunnel, &iph6->daddr);
if (!dst) {
struct neighbour *neigh = NULL;
bool do_tx_error = false;
if (skb_dst(skb))
neigh = dst_neigh_lookup(skb_dst(skb), &iph6->daddr);
if (!neigh) {
net_dbg_ratelimited("nexthop == NULL\n");
goto tx_error;
}
addr6 = (const struct in6_addr *)&neigh->primary_key;
addr_type = ipv6_addr_type(addr6);
if (addr_type == IPV6_ADDR_ANY) {
addr6 = &ipv6_hdr(skb)->daddr;
addr_type = ipv6_addr_type(addr6);
}
if ((addr_type & IPV6_ADDR_COMPATv4) != 0)
dst = addr6->s6_addr32[3];
else
do_tx_error = true;
neigh_release(neigh);
if (do_tx_error)
goto tx_error;
}
flowi4_init_output(&fl4, tunnel->parms.link, tunnel->fwmark,
RT_TOS(tos), RT_SCOPE_UNIVERSE, IPPROTO_IPV6,
0, dst, tiph->saddr, 0, 0,
sock_net_uid(tunnel->net, NULL));
rt = ip_route_output_flow(tunnel->net, &fl4, NULL);
if (IS_ERR(rt)) {
dev->stats.tx_carrier_errors++;
goto tx_error_icmp;
}
if (rt->rt_type != RTN_UNICAST) {
ip_rt_put(rt);
dev->stats.tx_carrier_errors++;
goto tx_error_icmp;
}
tdev = rt->dst.dev;
if (tdev == dev) {
ip_rt_put(rt);
dev->stats.collisions++;
goto tx_error;
}
if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4)) {
ip_rt_put(rt);
goto tx_error;
}
if (df) {
mtu = dst_mtu(&rt->dst) - t_hlen;
if (mtu < 68) {
dev->stats.collisions++;
ip_rt_put(rt);
goto tx_error;
}
if (mtu < IPV6_MIN_MTU) {
mtu = IPV6_MIN_MTU;
df = 0;
}
if (tunnel->parms.iph.daddr)
skb_dst_update_pmtu(skb, mtu);
if (skb->len > mtu && !skb_is_gso(skb)) {
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
ip_rt_put(rt);
goto tx_error;
}
}
if (tunnel->err_count > 0) {
if (time_before(jiffies,
tunnel->err_time + IPTUNNEL_ERR_TIMEO)) {
tunnel->err_count--;
dst_link_failure(skb);
} else
tunnel->err_count = 0;
}
/*
* Okay, now see if we can stuff it in the buffer as-is.
*/
max_headroom = LL_RESERVED_SPACE(tdev) + t_hlen;
if (skb_headroom(skb) < max_headroom || skb_shared(skb) ||
(skb_cloned(skb) && !skb_clone_writable(skb, 0))) {
struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom);
if (!new_skb) {
ip_rt_put(rt);
dev->stats.tx_dropped++;
kfree_skb(skb);
return NETDEV_TX_OK;
}
if (skb->sk)
skb_set_owner_w(new_skb, skb->sk);
dev_kfree_skb(skb);
skb = new_skb;
iph6 = ipv6_hdr(skb);
}
ttl = tiph->ttl;
if (ttl == 0)
ttl = iph6->hop_limit;
tos = INET_ECN_encapsulate(tos, ipv6_get_dsfield(iph6));
if (ip_tunnel_encap(skb, tunnel, &protocol, &fl4) < 0) {
ip_rt_put(rt);
goto tx_error;
}
skb_set_inner_ipproto(skb, IPPROTO_IPV6);
iptunnel_xmit(NULL, rt, skb, fl4.saddr, fl4.daddr, protocol, tos, ttl,
df, !net_eq(tunnel->net, dev_net(dev)));
return NETDEV_TX_OK;
tx_error_icmp:
dst_link_failure(skb);
tx_error:
kfree_skb(skb);
dev->stats.tx_errors++;
return NETDEV_TX_OK;
}
static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb,
struct net_device *dev, u8 ipproto)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
const struct iphdr *tiph = &tunnel->parms.iph;
if (iptunnel_handle_offloads(skb, SKB_GSO_IPXIP4))
goto tx_error;
skb_set_inner_ipproto(skb, ipproto);
ip_tunnel_xmit(skb, dev, tiph, ipproto);
return NETDEV_TX_OK;
tx_error:
kfree_skb(skb);
dev->stats.tx_errors++;
return NETDEV_TX_OK;
}
static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb,
struct net_device *dev)
{
if (!pskb_inet_may_pull(skb))
goto tx_err;
switch (skb->protocol) {
case htons(ETH_P_IP):
sit_tunnel_xmit__(skb, dev, IPPROTO_IPIP);
break;
case htons(ETH_P_IPV6):
ipip6_tunnel_xmit(skb, dev);
break;
#if IS_ENABLED(CONFIG_MPLS)
case htons(ETH_P_MPLS_UC):
sit_tunnel_xmit__(skb, dev, IPPROTO_MPLS);
break;
#endif
default:
goto tx_err;
}
return NETDEV_TX_OK;
tx_err:
dev->stats.tx_errors++;
kfree_skb(skb);
return NETDEV_TX_OK;
}
static void ipip6_tunnel_bind_dev(struct net_device *dev)
{
struct net_device *tdev = NULL;
struct ip_tunnel *tunnel;
const struct iphdr *iph;
struct flowi4 fl4;
tunnel = netdev_priv(dev);
iph = &tunnel->parms.iph;
if (iph->daddr) {
struct rtable *rt = ip_route_output_ports(tunnel->net, &fl4,
NULL,
iph->daddr, iph->saddr,
0, 0,
IPPROTO_IPV6,
RT_TOS(iph->tos),
tunnel->parms.link);
if (!IS_ERR(rt)) {
tdev = rt->dst.dev;
ip_rt_put(rt);
}
dev->flags |= IFF_POINTOPOINT;
}
if (!tdev && tunnel->parms.link)
tdev = __dev_get_by_index(tunnel->net, tunnel->parms.link);
if (tdev) {
int t_hlen = tunnel->hlen + sizeof(struct iphdr);
dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
dev->mtu = tdev->mtu - t_hlen;
if (dev->mtu < IPV6_MIN_MTU)
dev->mtu = IPV6_MIN_MTU;
}
}
static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm *p,
__u32 fwmark)
{
struct net *net = t->net;
struct sit_net *sitn = net_generic(net, sit_net_id);
ipip6_tunnel_unlink(sitn, t);
synchronize_net();
t->parms.iph.saddr = p->iph.saddr;
t->parms.iph.daddr = p->iph.daddr;
memcpy(t->dev->dev_addr, &p->iph.saddr, 4);
memcpy(t->dev->broadcast, &p->iph.daddr, 4);
ipip6_tunnel_link(sitn, t);
t->parms.iph.ttl = p->iph.ttl;
t->parms.iph.tos = p->iph.tos;
t->parms.iph.frag_off = p->iph.frag_off;
if (t->parms.link != p->link || t->fwmark != fwmark) {
t->parms.link = p->link;
t->fwmark = fwmark;
ipip6_tunnel_bind_dev(t->dev);
}
dst_cache_reset(&t->dst_cache);
netdev_state_change(t->dev);
}
#ifdef CONFIG_IPV6_SIT_6RD
static int ipip6_tunnel_update_6rd(struct ip_tunnel *t,
struct ip_tunnel_6rd *ip6rd)
{
struct in6_addr prefix;
__be32 relay_prefix;
if (ip6rd->relay_prefixlen > 32 ||
ip6rd->prefixlen + (32 - ip6rd->relay_prefixlen) > 64)
return -EINVAL;
ipv6_addr_prefix(&prefix, &ip6rd->prefix, ip6rd->prefixlen);
if (!ipv6_addr_equal(&prefix, &ip6rd->prefix))
return -EINVAL;
if (ip6rd->relay_prefixlen)
relay_prefix = ip6rd->relay_prefix &
htonl(0xffffffffUL <<
(32 - ip6rd->relay_prefixlen));
else
relay_prefix = 0;
if (relay_prefix != ip6rd->relay_prefix)
return -EINVAL;
t->ip6rd.prefix = prefix;
t->ip6rd.relay_prefix = relay_prefix;
t->ip6rd.prefixlen = ip6rd->prefixlen;
t->ip6rd.relay_prefixlen = ip6rd->relay_prefixlen;
dst_cache_reset(&t->dst_cache);
netdev_state_change(t->dev);
return 0;
}
#endif
static bool ipip6_valid_ip_proto(u8 ipproto)
{
return ipproto == IPPROTO_IPV6 ||
ipproto == IPPROTO_IPIP ||
#if IS_ENABLED(CONFIG_MPLS)
ipproto == IPPROTO_MPLS ||
#endif
ipproto == 0;
}
static int
ipip6_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
int err = 0;
struct ip_tunnel_parm p;
struct ip_tunnel_prl prl;
struct ip_tunnel *t = netdev_priv(dev);
struct net *net = t->net;
struct sit_net *sitn = net_generic(net, sit_net_id);
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd ip6rd;
#endif
switch (cmd) {
case SIOCGETTUNNEL:
#ifdef CONFIG_IPV6_SIT_6RD
case SIOCGET6RD:
#endif
if (dev == sitn->fb_tunnel_dev) {
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
err = -EFAULT;
break;
}
t = ipip6_tunnel_locate(net, &p, 0);
if (!t)
t = netdev_priv(dev);
}
err = -EFAULT;
if (cmd == SIOCGETTUNNEL) {
memcpy(&p, &t->parms, sizeof(p));
if (copy_to_user(ifr->ifr_ifru.ifru_data, &p,
sizeof(p)))
goto done;
#ifdef CONFIG_IPV6_SIT_6RD
} else {
ip6rd.prefix = t->ip6rd.prefix;
ip6rd.relay_prefix = t->ip6rd.relay_prefix;
ip6rd.prefixlen = t->ip6rd.prefixlen;
ip6rd.relay_prefixlen = t->ip6rd.relay_prefixlen;
if (copy_to_user(ifr->ifr_ifru.ifru_data, &ip6rd,
sizeof(ip6rd)))
goto done;
#endif
}
err = 0;
break;
case SIOCADDTUNNEL:
case SIOCCHGTUNNEL:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
goto done;
err = -EFAULT;
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
goto done;
err = -EINVAL;
if (!ipip6_valid_ip_proto(p.iph.protocol))
goto done;
if (p.iph.version != 4 ||
p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
goto done;
if (p.iph.ttl)
p.iph.frag_off |= htons(IP_DF);
t = ipip6_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
if (dev != sitn->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
if (t) {
if (t->dev != dev) {
err = -EEXIST;
break;
}
} else {
if (((dev->flags&IFF_POINTOPOINT) && !p.iph.daddr) ||
(!(dev->flags&IFF_POINTOPOINT) && p.iph.daddr)) {
err = -EINVAL;
break;
}
t = netdev_priv(dev);
}
ipip6_tunnel_update(t, &p, t->fwmark);
}
if (t) {
err = 0;
if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
err = -EFAULT;
} else
err = (cmd == SIOCADDTUNNEL ? -ENOBUFS : -ENOENT);
break;
case SIOCDELTUNNEL:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
goto done;
if (dev == sitn->fb_tunnel_dev) {
err = -EFAULT;
if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
goto done;
err = -ENOENT;
t = ipip6_tunnel_locate(net, &p, 0);
if (!t)
goto done;
err = -EPERM;
if (t == netdev_priv(sitn->fb_tunnel_dev))
goto done;
dev = t->dev;
}
unregister_netdevice(dev);
err = 0;
break;
case SIOCGETPRL:
err = -EINVAL;
if (dev == sitn->fb_tunnel_dev)
goto done;
err = ipip6_tunnel_get_prl(t, ifr->ifr_ifru.ifru_data);
break;
case SIOCADDPRL:
case SIOCDELPRL:
case SIOCCHGPRL:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
goto done;
err = -EINVAL;
if (dev == sitn->fb_tunnel_dev)
goto done;
err = -EFAULT;
if (copy_from_user(&prl, ifr->ifr_ifru.ifru_data, sizeof(prl)))
goto done;
switch (cmd) {
case SIOCDELPRL:
err = ipip6_tunnel_del_prl(t, &prl);
break;
case SIOCADDPRL:
case SIOCCHGPRL:
err = ipip6_tunnel_add_prl(t, &prl, cmd == SIOCCHGPRL);
break;
}
dst_cache_reset(&t->dst_cache);
netdev_state_change(dev);
break;
#ifdef CONFIG_IPV6_SIT_6RD
case SIOCADD6RD:
case SIOCCHG6RD:
case SIOCDEL6RD:
err = -EPERM;
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
goto done;
err = -EFAULT;
if (copy_from_user(&ip6rd, ifr->ifr_ifru.ifru_data,
sizeof(ip6rd)))
goto done;
if (cmd != SIOCDEL6RD) {
err = ipip6_tunnel_update_6rd(t, &ip6rd);
if (err < 0)
goto done;
} else
ipip6_tunnel_clone_6rd(dev, sitn);
err = 0;
break;
#endif
default:
err = -EINVAL;
}
done:
return err;
}
static const struct net_device_ops ipip6_netdev_ops = {
.ndo_init = ipip6_tunnel_init,
.ndo_uninit = ipip6_tunnel_uninit,
.ndo_start_xmit = sit_tunnel_xmit,
.ndo_do_ioctl = ipip6_tunnel_ioctl,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_get_iflink = ip_tunnel_get_iflink,
};
static void ipip6_dev_free(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
dst_cache_destroy(&tunnel->dst_cache);
free_percpu(dev->tstats);
}
#define SIT_FEATURES (NETIF_F_SG | \
NETIF_F_FRAGLIST | \
NETIF_F_HIGHDMA | \
NETIF_F_GSO_SOFTWARE | \
NETIF_F_HW_CSUM)
static void ipip6_tunnel_setup(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
int t_hlen = tunnel->hlen + sizeof(struct iphdr);
dev->netdev_ops = &ipip6_netdev_ops;
dev->needs_free_netdev = true;
dev->priv_destructor = ipip6_dev_free;
dev->type = ARPHRD_SIT;
dev->hard_header_len = LL_MAX_HEADER + t_hlen;
dev->mtu = ETH_DATA_LEN - t_hlen;
dev->min_mtu = IPV6_MIN_MTU;
dev->max_mtu = IP6_MAX_MTU - t_hlen;
dev->flags = IFF_NOARP;
netif_keep_dst(dev);
dev->addr_len = 4;
dev->features |= NETIF_F_LLTX;
dev->features |= SIT_FEATURES;
dev->hw_features |= SIT_FEATURES;
}
static int ipip6_tunnel_init(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
int err;
tunnel->dev = dev;
tunnel->net = dev_net(dev);
strcpy(tunnel->parms.name, dev->name);
ipip6_tunnel_bind_dev(dev);
dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
if (!dev->tstats)
return -ENOMEM;
err = dst_cache_init(&tunnel->dst_cache, GFP_KERNEL);
if (err) {
free_percpu(dev->tstats);
dev->tstats = NULL;
return err;
}
return 0;
}
static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
struct iphdr *iph = &tunnel->parms.iph;
struct net *net = dev_net(dev);
struct sit_net *sitn = net_generic(net, sit_net_id);
iph->version = 4;
iph->protocol = IPPROTO_IPV6;
iph->ihl = 5;
iph->ttl = 64;
dev_hold(dev);
rcu_assign_pointer(sitn->tunnels_wc[0], tunnel);
}
static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
u8 proto;
if (!data || !data[IFLA_IPTUN_PROTO])
return 0;
proto = nla_get_u8(data[IFLA_IPTUN_PROTO]);
if (!ipip6_valid_ip_proto(proto))
return -EINVAL;
return 0;
}
static void ipip6_netlink_parms(struct nlattr *data[],
struct ip_tunnel_parm *parms,
__u32 *fwmark)
{
memset(parms, 0, sizeof(*parms));
parms->iph.version = 4;
parms->iph.protocol = IPPROTO_IPV6;
parms->iph.ihl = 5;
parms->iph.ttl = 64;
if (!data)
return;
if (data[IFLA_IPTUN_LINK])
parms->link = nla_get_u32(data[IFLA_IPTUN_LINK]);
if (data[IFLA_IPTUN_LOCAL])
parms->iph.saddr = nla_get_be32(data[IFLA_IPTUN_LOCAL]);
if (data[IFLA_IPTUN_REMOTE])
parms->iph.daddr = nla_get_be32(data[IFLA_IPTUN_REMOTE]);
if (data[IFLA_IPTUN_TTL]) {
parms->iph.ttl = nla_get_u8(data[IFLA_IPTUN_TTL]);
if (parms->iph.ttl)
parms->iph.frag_off = htons(IP_DF);
}
if (data[IFLA_IPTUN_TOS])
parms->iph.tos = nla_get_u8(data[IFLA_IPTUN_TOS]);
if (!data[IFLA_IPTUN_PMTUDISC] || nla_get_u8(data[IFLA_IPTUN_PMTUDISC]))
parms->iph.frag_off = htons(IP_DF);
if (data[IFLA_IPTUN_FLAGS])
parms->i_flags = nla_get_be16(data[IFLA_IPTUN_FLAGS]);
if (data[IFLA_IPTUN_PROTO])
parms->iph.protocol = nla_get_u8(data[IFLA_IPTUN_PROTO]);
if (data[IFLA_IPTUN_FWMARK])
*fwmark = nla_get_u32(data[IFLA_IPTUN_FWMARK]);
}
/* This function returns true when ENCAP attributes are present in the nl msg */
static bool ipip6_netlink_encap_parms(struct nlattr *data[],
struct ip_tunnel_encap *ipencap)
{
bool ret = false;
memset(ipencap, 0, sizeof(*ipencap));
if (!data)
return ret;
if (data[IFLA_IPTUN_ENCAP_TYPE]) {
ret = true;
ipencap->type = nla_get_u16(data[IFLA_IPTUN_ENCAP_TYPE]);
}
if (data[IFLA_IPTUN_ENCAP_FLAGS]) {
ret = true;
ipencap->flags = nla_get_u16(data[IFLA_IPTUN_ENCAP_FLAGS]);
}
if (data[IFLA_IPTUN_ENCAP_SPORT]) {
ret = true;
ipencap->sport = nla_get_be16(data[IFLA_IPTUN_ENCAP_SPORT]);
}
if (data[IFLA_IPTUN_ENCAP_DPORT]) {
ret = true;
ipencap->dport = nla_get_be16(data[IFLA_IPTUN_ENCAP_DPORT]);
}
return ret;
}
#ifdef CONFIG_IPV6_SIT_6RD
/* This function returns true when 6RD attributes are present in the nl msg */
static bool ipip6_netlink_6rd_parms(struct nlattr *data[],
struct ip_tunnel_6rd *ip6rd)
{
bool ret = false;
memset(ip6rd, 0, sizeof(*ip6rd));
if (!data)
return ret;
if (data[IFLA_IPTUN_6RD_PREFIX]) {
ret = true;
ip6rd->prefix = nla_get_in6_addr(data[IFLA_IPTUN_6RD_PREFIX]);
}
if (data[IFLA_IPTUN_6RD_RELAY_PREFIX]) {
ret = true;
ip6rd->relay_prefix =
nla_get_be32(data[IFLA_IPTUN_6RD_RELAY_PREFIX]);
}
if (data[IFLA_IPTUN_6RD_PREFIXLEN]) {
ret = true;
ip6rd->prefixlen = nla_get_u16(data[IFLA_IPTUN_6RD_PREFIXLEN]);
}
if (data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]) {
ret = true;
ip6rd->relay_prefixlen =
nla_get_u16(data[IFLA_IPTUN_6RD_RELAY_PREFIXLEN]);
}
return ret;
}
#endif
static int ipip6_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct net *net = dev_net(dev);
struct ip_tunnel *nt;
struct ip_tunnel_encap ipencap;
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd ip6rd;
#endif
int err;
nt = netdev_priv(dev);
if (ipip6_netlink_encap_parms(data, &ipencap)) {
err = ip_tunnel_encap_setup(nt, &ipencap);
if (err < 0)
return err;
}
ipip6_netlink_parms(data, &nt->parms, &nt->fwmark);
if (ipip6_tunnel_locate(net, &nt->parms, 0))
return -EEXIST;
err = ipip6_tunnel_create(dev);
if (err < 0)
return err;
if (tb[IFLA_MTU]) {
u32 mtu = nla_get_u32(tb[IFLA_MTU]);
if (mtu >= IPV6_MIN_MTU &&
mtu <= IP6_MAX_MTU - dev->hard_header_len)
dev->mtu = mtu;
}
#ifdef CONFIG_IPV6_SIT_6RD
if (ipip6_netlink_6rd_parms(data, &ip6rd))
err = ipip6_tunnel_update_6rd(nt, &ip6rd);
#endif
return err;
}
static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[],
struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct ip_tunnel *t = netdev_priv(dev);
struct ip_tunnel_parm p;
struct ip_tunnel_encap ipencap;
struct net *net = t->net;
struct sit_net *sitn = net_generic(net, sit_net_id);
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd ip6rd;
#endif
__u32 fwmark = t->fwmark;
int err;
if (dev == sitn->fb_tunnel_dev)
return -EINVAL;
if (ipip6_netlink_encap_parms(data, &ipencap)) {
err = ip_tunnel_encap_setup(t, &ipencap);
if (err < 0)
return err;
}
ipip6_netlink_parms(data, &p, &fwmark);
if (((dev->flags & IFF_POINTOPOINT) && !p.iph.daddr) ||
(!(dev->flags & IFF_POINTOPOINT) && p.iph.daddr))
return -EINVAL;
t = ipip6_tunnel_locate(net, &p, 0);
if (t) {
if (t->dev != dev)
return -EEXIST;
} else
t = netdev_priv(dev);
ipip6_tunnel_update(t, &p, fwmark);
#ifdef CONFIG_IPV6_SIT_6RD
if (ipip6_netlink_6rd_parms(data, &ip6rd))
return ipip6_tunnel_update_6rd(t, &ip6rd);
#endif
return 0;
}
static size_t ipip6_get_size(const struct net_device *dev)
{
return
/* IFLA_IPTUN_LINK */
nla_total_size(4) +
/* IFLA_IPTUN_LOCAL */
nla_total_size(4) +
/* IFLA_IPTUN_REMOTE */
nla_total_size(4) +
/* IFLA_IPTUN_TTL */
nla_total_size(1) +
/* IFLA_IPTUN_TOS */
nla_total_size(1) +
/* IFLA_IPTUN_PMTUDISC */
nla_total_size(1) +
/* IFLA_IPTUN_FLAGS */
nla_total_size(2) +
/* IFLA_IPTUN_PROTO */
nla_total_size(1) +
#ifdef CONFIG_IPV6_SIT_6RD
/* IFLA_IPTUN_6RD_PREFIX */
nla_total_size(sizeof(struct in6_addr)) +
/* IFLA_IPTUN_6RD_RELAY_PREFIX */
nla_total_size(4) +
/* IFLA_IPTUN_6RD_PREFIXLEN */
nla_total_size(2) +
/* IFLA_IPTUN_6RD_RELAY_PREFIXLEN */
nla_total_size(2) +
#endif
/* IFLA_IPTUN_ENCAP_TYPE */
nla_total_size(2) +
/* IFLA_IPTUN_ENCAP_FLAGS */
nla_total_size(2) +
/* IFLA_IPTUN_ENCAP_SPORT */
nla_total_size(2) +
/* IFLA_IPTUN_ENCAP_DPORT */
nla_total_size(2) +
/* IFLA_IPTUN_FWMARK */
nla_total_size(4) +
0;
}
static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
struct ip_tunnel_parm *parm = &tunnel->parms;
if (nla_put_u32(skb, IFLA_IPTUN_LINK, parm->link) ||
nla_put_in_addr(skb, IFLA_IPTUN_LOCAL, parm->iph.saddr) ||
nla_put_in_addr(skb, IFLA_IPTUN_REMOTE, parm->iph.daddr) ||
nla_put_u8(skb, IFLA_IPTUN_TTL, parm->iph.ttl) ||
nla_put_u8(skb, IFLA_IPTUN_TOS, parm->iph.tos) ||
nla_put_u8(skb, IFLA_IPTUN_PMTUDISC,
!!(parm->iph.frag_off & htons(IP_DF))) ||
nla_put_u8(skb, IFLA_IPTUN_PROTO, parm->iph.protocol) ||
nla_put_be16(skb, IFLA_IPTUN_FLAGS, parm->i_flags) ||
nla_put_u32(skb, IFLA_IPTUN_FWMARK, tunnel->fwmark))
goto nla_put_failure;
#ifdef CONFIG_IPV6_SIT_6RD
if (nla_put_in6_addr(skb, IFLA_IPTUN_6RD_PREFIX,
&tunnel->ip6rd.prefix) ||
nla_put_in_addr(skb, IFLA_IPTUN_6RD_RELAY_PREFIX,
tunnel->ip6rd.relay_prefix) ||
nla_put_u16(skb, IFLA_IPTUN_6RD_PREFIXLEN,
tunnel->ip6rd.prefixlen) ||
nla_put_u16(skb, IFLA_IPTUN_6RD_RELAY_PREFIXLEN,
tunnel->ip6rd.relay_prefixlen))
goto nla_put_failure;
#endif
if (nla_put_u16(skb, IFLA_IPTUN_ENCAP_TYPE,
tunnel->encap.type) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_SPORT,
tunnel->encap.sport) ||
nla_put_be16(skb, IFLA_IPTUN_ENCAP_DPORT,
tunnel->encap.dport) ||
nla_put_u16(skb, IFLA_IPTUN_ENCAP_FLAGS,
tunnel->encap.flags))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = {
[IFLA_IPTUN_LINK] = { .type = NLA_U32 },
[IFLA_IPTUN_LOCAL] = { .type = NLA_U32 },
[IFLA_IPTUN_REMOTE] = { .type = NLA_U32 },
[IFLA_IPTUN_TTL] = { .type = NLA_U8 },
[IFLA_IPTUN_TOS] = { .type = NLA_U8 },
[IFLA_IPTUN_PMTUDISC] = { .type = NLA_U8 },
[IFLA_IPTUN_FLAGS] = { .type = NLA_U16 },
[IFLA_IPTUN_PROTO] = { .type = NLA_U8 },
#ifdef CONFIG_IPV6_SIT_6RD
[IFLA_IPTUN_6RD_PREFIX] = { .len = sizeof(struct in6_addr) },
[IFLA_IPTUN_6RD_RELAY_PREFIX] = { .type = NLA_U32 },
[IFLA_IPTUN_6RD_PREFIXLEN] = { .type = NLA_U16 },
[IFLA_IPTUN_6RD_RELAY_PREFIXLEN] = { .type = NLA_U16 },
#endif
[IFLA_IPTUN_ENCAP_TYPE] = { .type = NLA_U16 },
[IFLA_IPTUN_ENCAP_FLAGS] = { .type = NLA_U16 },
[IFLA_IPTUN_ENCAP_SPORT] = { .type = NLA_U16 },
[IFLA_IPTUN_ENCAP_DPORT] = { .type = NLA_U16 },
[IFLA_IPTUN_FWMARK] = { .type = NLA_U32 },
};
static void ipip6_dellink(struct net_device *dev, struct list_head *head)
{
struct net *net = dev_net(dev);
struct sit_net *sitn = net_generic(net, sit_net_id);
if (dev != sitn->fb_tunnel_dev)
unregister_netdevice_queue(dev, head);
}
static struct rtnl_link_ops sit_link_ops __read_mostly = {
.kind = "sit",
.maxtype = IFLA_IPTUN_MAX,
.policy = ipip6_policy,
.priv_size = sizeof(struct ip_tunnel),
.setup = ipip6_tunnel_setup,
.validate = ipip6_validate,
.newlink = ipip6_newlink,
.changelink = ipip6_changelink,
.get_size = ipip6_get_size,
.fill_info = ipip6_fill_info,
.dellink = ipip6_dellink,
.get_link_net = ip_tunnel_get_link_net,
};
static struct xfrm_tunnel sit_handler __read_mostly = {
.handler = ipip6_rcv,
.err_handler = ipip6_err,
.priority = 1,
};
static struct xfrm_tunnel ipip_handler __read_mostly = {
.handler = ipip_rcv,
.err_handler = ipip6_err,
.priority = 2,
};
#if IS_ENABLED(CONFIG_MPLS)
static struct xfrm_tunnel mplsip_handler __read_mostly = {
.handler = mplsip_rcv,
.err_handler = ipip6_err,
.priority = 2,
};
#endif
static void __net_exit sit_destroy_tunnels(struct net *net,
struct list_head *head)
{
struct sit_net *sitn = net_generic(net, sit_net_id);
struct net_device *dev, *aux;
int prio;
for_each_netdev_safe(net, dev, aux)
if (dev->rtnl_link_ops == &sit_link_ops)
unregister_netdevice_queue(dev, head);
for (prio = 1; prio < 4; prio++) {
int h;
for (h = 0; h < IP6_SIT_HASH_SIZE; h++) {
struct ip_tunnel *t;
t = rtnl_dereference(sitn->tunnels[prio][h]);
while (t) {
/* If dev is in the same netns, it has already
* been added to the list by the previous loop.
*/
if (!net_eq(dev_net(t->dev), net))
unregister_netdevice_queue(t->dev,
head);
t = rtnl_dereference(t->next);
}
}
}
}
static int __net_init sit_init_net(struct net *net)
{
struct sit_net *sitn = net_generic(net, sit_net_id);
struct ip_tunnel *t;
int err;
sitn->tunnels[0] = sitn->tunnels_wc;
sitn->tunnels[1] = sitn->tunnels_l;
sitn->tunnels[2] = sitn->tunnels_r;
sitn->tunnels[3] = sitn->tunnels_r_l;
if (!net_has_fallback_tunnels(net))
return 0;
sitn->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "sit0",
NET_NAME_UNKNOWN,
ipip6_tunnel_setup);
if (!sitn->fb_tunnel_dev) {
err = -ENOMEM;
goto err_alloc_dev;
}
dev_net_set(sitn->fb_tunnel_dev, net);
sitn->fb_tunnel_dev->rtnl_link_ops = &sit_link_ops;
/* FB netdevice is special: we have one, and only one per netns.
* Allowing to move it to another netns is clearly unsafe.
*/
sitn->fb_tunnel_dev->features |= NETIF_F_NETNS_LOCAL;
err = register_netdev(sitn->fb_tunnel_dev);
if (err)
goto err_reg_dev;
ipip6_tunnel_clone_6rd(sitn->fb_tunnel_dev, sitn);
ipip6_fb_tunnel_init(sitn->fb_tunnel_dev);
t = netdev_priv(sitn->fb_tunnel_dev);
strcpy(t->parms.name, sitn->fb_tunnel_dev->name);
return 0;
err_reg_dev:
ipip6_dev_free(sitn->fb_tunnel_dev);
free_netdev(sitn->fb_tunnel_dev);
err_alloc_dev:
return err;
}
static void __net_exit sit_exit_batch_net(struct list_head *net_list)
{
LIST_HEAD(list);
struct net *net;
rtnl_lock();
list_for_each_entry(net, net_list, exit_list)
sit_destroy_tunnels(net, &list);
unregister_netdevice_many(&list);
rtnl_unlock();
}
static struct pernet_operations sit_net_ops = {
.init = sit_init_net,
.exit_batch = sit_exit_batch_net,
.id = &sit_net_id,
.size = sizeof(struct sit_net),
};
static void __exit sit_cleanup(void)
{
rtnl_link_unregister(&sit_link_ops);
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
#if IS_ENABLED(CONFIG_MPLS)
xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
#endif
unregister_pernet_device(&sit_net_ops);
rcu_barrier(); /* Wait for completion of call_rcu()'s */
}
static int __init sit_init(void)
{
int err;
pr_info("IPv6, IPv4 and MPLS over IPv4 tunneling driver\n");
err = register_pernet_device(&sit_net_ops);
if (err < 0)
return err;
err = xfrm4_tunnel_register(&sit_handler, AF_INET6);
if (err < 0) {
pr_info("%s: can't register ip6ip4\n", __func__);
goto xfrm_tunnel_failed;
}
err = xfrm4_tunnel_register(&ipip_handler, AF_INET);
if (err < 0) {
pr_info("%s: can't register ip4ip4\n", __func__);
goto xfrm_tunnel4_failed;
}
#if IS_ENABLED(CONFIG_MPLS)
err = xfrm4_tunnel_register(&mplsip_handler, AF_MPLS);
if (err < 0) {
pr_info("%s: can't register mplsip\n", __func__);
goto xfrm_tunnel_mpls_failed;
}
#endif
err = rtnl_link_register(&sit_link_ops);
if (err < 0)
goto rtnl_link_failed;
out:
return err;
rtnl_link_failed:
#if IS_ENABLED(CONFIG_MPLS)
xfrm4_tunnel_deregister(&mplsip_handler, AF_MPLS);
xfrm_tunnel_mpls_failed:
#endif
xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
xfrm_tunnel4_failed:
xfrm4_tunnel_deregister(&sit_handler, AF_INET6);
xfrm_tunnel_failed:
unregister_pernet_device(&sit_net_ops);
goto out;
}
module_init(sit_init);
module_exit(sit_cleanup);
MODULE_LICENSE("GPL");
MODULE_ALIAS_RTNL_LINK("sit");
MODULE_ALIAS_NETDEV("sit0");