Add tou_encap structure to inet_sock. In transmit path (ip_queue_xmit)
check if encapsulation is enabled and call the build header op
if it is. Add IP_TOU_ENCAP setsockopt for IPv4 sockets.
Signed-off-by: Tom Herbert <t...@herbertland.com>
---
include/uapi/linux/in.h | 1 +
net/ipv4/ip_output.c | 42 ++++++++++++++++++++++++++++++++++++------
net/ipv4/ip_sockglue.c | 7 +++++++
net/ipv4/tou.c | 2 +-
4 files changed, 45 insertions(+), 7 deletions(-)
diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h
index eaf9491..9827bff 100644
--- a/include/uapi/linux/in.h
+++ b/include/uapi/linux/in.h
@@ -152,6 +152,7 @@ struct in_addr {
#define MCAST_MSFILTER 48
#define IP_MULTICAST_ALL 49
#define IP_UNICAST_IF 50
+#define IP_TOU_ENCAP 51
#define MCAST_EXCLUDE 0
#define MCAST_INCLUDE 1
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index cbac493..11cf4de 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -78,6 +78,7 @@
#include <linux/netfilter_bridge.h>
#include <linux/netlink.h>
#include <linux/tcp.h>
+#include <net/ip_tunnels.h>
static int
ip_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
@@ -382,11 +383,38 @@ int ip_queue_xmit(struct sock *sk, struct sk_buff *skb,
struct flowi *fl)
struct rtable *rt;
struct iphdr *iph;
int res;
+ __be16 dport, sport;
+ u8 protocol = sk->sk_protocol;
+ struct ip_tunnel_encap *e;
/* Skip all of this if the packet is already routed,
* f.e. by something like SCTP.
*/
rcu_read_lock();
+
+ e = rcu_dereference(inet->tou_encap);
+ if (e) {
+ const struct ip_tunnel_encap_ops *ops;
+
+ /* Transport layer protocol over UDP enapsulation */
+ dport = e->dport;
+ sport = e->sport;
+ ops = rcu_dereference(iptun_encaps[e->type]);
+ if (likely(ops && ops->build_header)) {
+ res = ops->build_header(skb, e, &protocol,
+ (struct flowi4 *)fl,
+ sock_net(sk));
+ if (res < 0)
+ goto fail;
+ } else {
+ res = -EINVAL;
+ goto fail;
+ }
+ } else {
+ dport = inet->inet_dport;
+ sport = inet->inet_sport;
+ }
+
inet_opt = rcu_dereference(inet->inet_opt);
fl4 = &fl->u.ip4;
rt = skb_rtable(skb);
@@ -409,9 +437,9 @@ int ip_queue_xmit(struct sock *sk, struct sk_buff *skb,
struct flowi *fl)
*/
rt = ip_route_output_ports(net, fl4, sk,
daddr, inet->inet_saddr,
- inet->inet_dport,
- inet->inet_sport,
- sk->sk_protocol,
+ dport,
+ sport,
+ protocol,
RT_CONN_FLAGS(sk),
sk->sk_bound_dev_if);
if (IS_ERR(rt))
@@ -434,7 +462,7 @@ packet_routed:
else
iph->frag_off = 0;
iph->ttl = ip_select_ttl(inet, &rt->dst);
- iph->protocol = sk->sk_protocol;
+ iph->protocol = protocol;
ip_copy_addrs(iph, fl4);
/* Transport layer set skb->h.foo itself. */
@@ -456,10 +484,12 @@ packet_routed:
return res;
no_route:
- rcu_read_unlock();
IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
+ res = -EHOSTUNREACH;
+fail:
+ rcu_read_unlock();
kfree_skb(skb);
- return -EHOSTUNREACH;
+ return res;
}
EXPORT_SYMBOL(ip_queue_xmit);
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 71a52f4d..0c9d3f0 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -42,6 +42,7 @@
#include <net/transp_v6.h>
#endif
#include <net/ip_fib.h>
+#include <net/tou.h>
#include <linux/errqueue.h>
#include <asm/uaccess.h>
@@ -1162,6 +1163,10 @@ mc_msf_out:
inet->min_ttl = val;
break;
+ case IP_TOU_ENCAP:
+ err = tou_encap_setsockopt(sk, optval, optlen, false);
+ break;
+
default:
err = -ENOPROTOOPT;
break;
@@ -1493,6 +1498,8 @@ static int do_ip_getsockopt(struct sock *sk, int level,
int optname,
case IP_MINTTL:
val = inet->min_ttl;
break;
+ case IPV6_TOU_ENCAP:
+ return tou_encap_getsockopt(sk, optval, len, optlen, false);
default:
release_sock(sk);
return -ENOPROTOOPT;
diff --git a/net/ipv4/tou.c b/net/ipv4/tou.c
index ef9999f..d3069a8 100644
--- a/net/ipv4/tou.c
+++ b/net/ipv4/tou.c
@@ -69,7 +69,7 @@ int tou_encap_setsockopt(struct sock *sk, char __user
*optval, int optlen,
encap.dport = te.dport;
encap.flags = te.flags;
- hlen = is_ipv6 ? ip6_encap_hlen(e) : ip_encap_hlen(e);
+ hlen = is_ipv6 ? ip6_encap_hlen(&encap) : ip_encap_hlen(&encap);
if (hlen < 0)
return hlen;
--
2.8.0.rc2
