aboutsummaryrefslogtreecommitdiffstats
path: root/net/ipv6/sit.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv6/sit.c')
-rw-r--r--net/ipv6/sit.c149
1 files changed, 120 insertions, 29 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 71433d29d884..e77239d02bf5 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -16,6 +16,7 @@
* Changes:
* Roger Venning <r.venning@telstra.com>: 6to4 support
* Nate Thompson <nate@thebog.net>: 6to4 support
+ * Fred L. Templin <fltemplin@acm.org>: isatap support
*/
#include <linux/module.h>
@@ -182,6 +183,9 @@ static struct ip_tunnel * ipip6_tunnel_locate(struct ip_tunnel_parm *parms, int
dev->init = ipip6_tunnel_init;
nt->parms = *parms;
+ if (parms->i_flags & SIT_ISATAP)
+ dev->priv_flags |= IFF_ISATAP;
+
if (register_netdevice(dev) < 0) {
free_netdev(dev);
goto failed;
@@ -364,6 +368,48 @@ static inline void ipip6_ecn_decapsulate(struct iphdr *iph, struct sk_buff *skb)
IP6_ECN_set_ce(ipv6_hdr(skb));
}
+/* ISATAP (RFC4214) - check source address */
+static int
+isatap_srcok(struct sk_buff *skb, struct iphdr *iph, struct net_device *dev)
+{
+ struct neighbour *neigh;
+ struct dst_entry *dst;
+ struct rt6_info *rt;
+ struct flowi fl;
+ struct in6_addr *addr6;
+ struct in6_addr rtr;
+ struct ipv6hdr *iph6;
+ int ok = 0;
+
+ /* from onlink default router */
+ ipv6_addr_set(&rtr, htonl(0xFE800000), 0, 0, 0);
+ ipv6_isatap_eui64(rtr.s6_addr + 8, iph->saddr);
+ if ((rt = rt6_get_dflt_router(&rtr, dev))) {
+ dst_release(&rt->u.dst);
+ return 1;
+ }
+
+ iph6 = ipv6_hdr(skb);
+ memset(&fl, 0, sizeof(fl));
+ fl.proto = iph6->nexthdr;
+ ipv6_addr_copy(&fl.fl6_dst, &iph6->saddr);
+ fl.oif = dev->ifindex;
+ security_skb_classify_flow(skb, &fl);
+
+ dst = ip6_route_output(NULL, &fl);
+ if (!dst->error && (dst->dev == dev) && (neigh = dst->neighbour)) {
+
+ addr6 = (struct in6_addr*)&neigh->primary_key;
+
+ /* from correct previous hop */
+ if (ipv6_addr_is_isatap(addr6) &&
+ (addr6->s6_addr32[3] == iph->saddr))
+ ok = 1;
+ }
+ dst_release(dst);
+ return ok;
+}
+
static int ipip6_rcv(struct sk_buff *skb)
{
struct iphdr *iph;
@@ -382,6 +428,14 @@ static int ipip6_rcv(struct sk_buff *skb)
IPCB(skb)->flags = 0;
skb->protocol = htons(ETH_P_IPV6);
skb->pkt_type = PACKET_HOST;
+
+ if ((tunnel->dev->priv_flags & IFF_ISATAP) &&
+ !isatap_srcok(skb, iph, tunnel->dev)) {
+ tunnel->stat.rx_errors++;
+ read_unlock(&ipip6_lock);
+ kfree_skb(skb);
+ return 0;
+ }
tunnel->stat.rx_packets++;
tunnel->stat.rx_bytes += skb->len;
skb->dev = tunnel->dev;
@@ -444,6 +498,29 @@ static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
if (skb->protocol != htons(ETH_P_IPV6))
goto tx_error;
+ /* ISATAP (RFC4214) - must come before 6to4 */
+ if (dev->priv_flags & IFF_ISATAP) {
+ struct neighbour *neigh = NULL;
+
+ if (skb->dst)
+ neigh = skb->dst->neighbour;
+
+ if (neigh == NULL) {
+ if (net_ratelimit())
+ printk(KERN_DEBUG "sit: nexthop == NULL\n");
+ goto tx_error;
+ }
+
+ addr6 = (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
+ goto tx_error;
+ }
+
if (!dst)
dst = try_6to4(&iph6->daddr);
@@ -480,7 +557,7 @@ static int ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
.tos = RT_TOS(tos) } },
.oif = tunnel->parms.link,
.proto = IPPROTO_IPV6 };
- if (ip_route_output_key(&rt, &fl)) {
+ if (ip_route_output_key(&init_net, &rt, &fl)) {
tunnel->stat.tx_carrier_errors++;
goto tx_error_icmp;
}
@@ -592,6 +669,42 @@ tx_error:
return 0;
}
+static void ipip6_tunnel_bind_dev(struct net_device *dev)
+{
+ struct net_device *tdev = NULL;
+ struct ip_tunnel *tunnel;
+ struct iphdr *iph;
+
+ tunnel = netdev_priv(dev);
+ iph = &tunnel->parms.iph;
+
+ if (iph->daddr) {
+ struct flowi fl = { .nl_u = { .ip4_u =
+ { .daddr = iph->daddr,
+ .saddr = iph->saddr,
+ .tos = RT_TOS(iph->tos) } },
+ .oif = tunnel->parms.link,
+ .proto = IPPROTO_IPV6 };
+ struct rtable *rt;
+ if (!ip_route_output_key(&init_net, &rt, &fl)) {
+ tdev = rt->u.dst.dev;
+ ip_rt_put(rt);
+ }
+ dev->flags |= IFF_POINTOPOINT;
+ }
+
+ if (!tdev && tunnel->parms.link)
+ tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
+
+ if (tdev) {
+ dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
+ dev->mtu = tdev->mtu - sizeof(struct iphdr);
+ if (dev->mtu < IPV6_MIN_MTU)
+ dev->mtu = IPV6_MIN_MTU;
+ }
+ dev->iflink = tunnel->parms.link;
+}
+
static int
ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
{
@@ -663,6 +776,11 @@ ipip6_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
if (cmd == SIOCCHGTUNNEL) {
t->parms.iph.ttl = p.iph.ttl;
t->parms.iph.tos = p.iph.tos;
+ if (t->parms.link != p.link) {
+ t->parms.link = p.link;
+ ipip6_tunnel_bind_dev(dev);
+ netdev_state_change(dev);
+ }
}
if (copy_to_user(ifr->ifr_ifru.ifru_data, &t->parms, sizeof(p)))
err = -EFAULT;
@@ -731,12 +849,9 @@ static void ipip6_tunnel_setup(struct net_device *dev)
static int ipip6_tunnel_init(struct net_device *dev)
{
- struct net_device *tdev = NULL;
struct ip_tunnel *tunnel;
- struct iphdr *iph;
tunnel = netdev_priv(dev);
- iph = &tunnel->parms.iph;
tunnel->dev = dev;
strcpy(tunnel->parms.name, dev->name);
@@ -744,31 +859,7 @@ static int ipip6_tunnel_init(struct net_device *dev)
memcpy(dev->dev_addr, &tunnel->parms.iph.saddr, 4);
memcpy(dev->broadcast, &tunnel->parms.iph.daddr, 4);
- if (iph->daddr) {
- struct flowi fl = { .nl_u = { .ip4_u =
- { .daddr = iph->daddr,
- .saddr = iph->saddr,
- .tos = RT_TOS(iph->tos) } },
- .oif = tunnel->parms.link,
- .proto = IPPROTO_IPV6 };
- struct rtable *rt;
- if (!ip_route_output_key(&rt, &fl)) {
- tdev = rt->u.dst.dev;
- ip_rt_put(rt);
- }
- dev->flags |= IFF_POINTOPOINT;
- }
-
- if (!tdev && tunnel->parms.link)
- tdev = __dev_get_by_index(&init_net, tunnel->parms.link);
-
- if (tdev) {
- dev->hard_header_len = tdev->hard_header_len + sizeof(struct iphdr);
- dev->mtu = tdev->mtu - sizeof(struct iphdr);
- if (dev->mtu < IPV6_MIN_MTU)
- dev->mtu = IPV6_MIN_MTU;
- }
- dev->iflink = tunnel->parms.link;
+ ipip6_tunnel_bind_dev(dev);
return 0;
}
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.