ip_tunnel: Ops registration for secondary encap (fou, gue)

Instead of calling fou and gue functions directly from ip_tunnel
use ops for these that were previously registered. This patch adds the
logic to add and remove encapsulation operations for ip_tunnel,
and modified fou (and gue) to register with ip_tunnels.

This patch also addresses a circular dependency between ip_tunnel
and fou that was causing link errors when CONFIG_NET_IP_TUNNEL=y
and CONFIG_NET_FOU=m. References to fou an gue have been removed from
ip_tunnel.c

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert 2014-11-12 11:54:09 -08:00 committed by David S. Miller
parent 4243cdc2c1
commit a8c5f90fb5
4 changed files with 157 additions and 47 deletions

View File

@ -8,31 +8,12 @@
#include <net/ip_tunnels.h>
#include <net/udp.h>
size_t fou_encap_hlen(struct ip_tunnel_encap *e);
static size_t gue_encap_hlen(struct ip_tunnel_encap *e);
int fou_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
u8 *protocol, struct flowi4 *fl4);
int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
u8 *protocol, struct flowi4 *fl4);
static size_t fou_encap_hlen(struct ip_tunnel_encap *e)
{
return sizeof(struct udphdr);
}
static size_t gue_encap_hlen(struct ip_tunnel_encap *e)
{
size_t len;
bool need_priv = false;
len = sizeof(struct udphdr) + sizeof(struct guehdr);
if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) {
len += GUE_PLEN_REMCSUM;
need_priv = true;
}
len += need_priv ? GUE_LEN_PRIV : 0;
return len;
}
#endif

View File

@ -117,6 +117,22 @@ struct ip_tunnel_net {
struct hlist_head tunnels[IP_TNL_HASH_SIZE];
};
struct ip_tunnel_encap_ops {
size_t (*encap_hlen)(struct ip_tunnel_encap *e);
int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e,
u8 *protocol, struct flowi4 *fl4);
};
#define MAX_IPTUN_ENCAP_OPS 8
extern const struct ip_tunnel_encap_ops __rcu *
iptun_encaps[MAX_IPTUN_ENCAP_OPS];
int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *op,
unsigned int num);
int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *op,
unsigned int num);
#ifdef CONFIG_INET
int ip_tunnel_init(struct net_device *dev);

View File

@ -668,6 +668,30 @@ static const struct genl_ops fou_nl_ops[] = {
},
};
size_t fou_encap_hlen(struct ip_tunnel_encap *e)
{
return sizeof(struct udphdr);
}
EXPORT_SYMBOL(fou_encap_hlen);
size_t gue_encap_hlen(struct ip_tunnel_encap *e)
{
size_t len;
bool need_priv = false;
len = sizeof(struct udphdr) + sizeof(struct guehdr);
if (e->flags & TUNNEL_ENCAP_FLAG_REMCSUM) {
len += GUE_PLEN_REMCSUM;
need_priv = true;
}
len += need_priv ? GUE_LEN_PRIV : 0;
return len;
}
EXPORT_SYMBOL(gue_encap_hlen);
static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
struct flowi4 *fl4, u8 *protocol, __be16 sport)
{
@ -787,6 +811,57 @@ int gue_build_header(struct sk_buff *skb, struct ip_tunnel_encap *e,
}
EXPORT_SYMBOL(gue_build_header);
#ifdef CONFIG_NET_FOU_IP_TUNNELS
static const struct ip_tunnel_encap_ops __read_mostly fou_iptun_ops = {
.encap_hlen = fou_encap_hlen,
.build_header = fou_build_header,
};
static const struct ip_tunnel_encap_ops __read_mostly gue_iptun_ops = {
.encap_hlen = gue_encap_hlen,
.build_header = gue_build_header,
};
static int ip_tunnel_encap_add_fou_ops(void)
{
int ret;
ret = ip_tunnel_encap_add_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
if (ret < 0) {
pr_err("can't add fou ops\n");
return ret;
}
ret = ip_tunnel_encap_add_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
if (ret < 0) {
pr_err("can't add gue ops\n");
ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
return ret;
}
return 0;
}
static void ip_tunnel_encap_del_fou_ops(void)
{
ip_tunnel_encap_del_ops(&fou_iptun_ops, TUNNEL_ENCAP_FOU);
ip_tunnel_encap_del_ops(&gue_iptun_ops, TUNNEL_ENCAP_GUE);
}
#else
static int ip_tunnel_encap_add_fou_ops(void)
{
return 0;
}
static int ip_tunnel_encap_del_fou_ops(void)
{
}
#endif
static int __init fou_init(void)
{
int ret;
@ -794,6 +869,14 @@ static int __init fou_init(void)
ret = genl_register_family_with_ops(&fou_nl_family,
fou_nl_ops);
if (ret < 0)
goto exit;
ret = ip_tunnel_encap_add_fou_ops();
if (ret < 0)
genl_unregister_family(&fou_nl_family);
exit:
return ret;
}
@ -801,6 +884,8 @@ static void __exit fou_fini(void)
{
struct fou *fou, *next;
ip_tunnel_encap_del_fou_ops();
genl_unregister_family(&fou_nl_family);
/* Close all the FOU sockets */

View File

@ -57,10 +57,6 @@
#include <net/rtnetlink.h>
#include <net/udp.h>
#if IS_ENABLED(CONFIG_NET_FOU)
#include <net/fou.h>
#endif
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/ip6_fib.h>
@ -494,20 +490,51 @@ EXPORT_SYMBOL_GPL(ip_tunnel_rcv);
static int ip_encap_hlen(struct ip_tunnel_encap *e)
{
switch (e->type) {
case TUNNEL_ENCAP_NONE:
const struct ip_tunnel_encap_ops *ops;
int hlen = -EINVAL;
if (e->type == TUNNEL_ENCAP_NONE)
return 0;
#if IS_ENABLED(CONFIG_NET_FOU)
case TUNNEL_ENCAP_FOU:
return fou_encap_hlen(e);
case TUNNEL_ENCAP_GUE:
return gue_encap_hlen(e);
#endif
default:
if (e->type >= MAX_IPTUN_ENCAP_OPS)
return -EINVAL;
}
rcu_read_lock();
ops = rcu_dereference(iptun_encaps[e->type]);
if (likely(ops && ops->encap_hlen))
hlen = ops->encap_hlen(e);
rcu_read_unlock();
return hlen;
}
const struct ip_tunnel_encap_ops __rcu *
iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly;
int ip_tunnel_encap_add_ops(const struct ip_tunnel_encap_ops *ops,
unsigned int num)
{
return !cmpxchg((const struct ip_tunnel_encap_ops **)
&iptun_encaps[num],
NULL, ops) ? 0 : -1;
}
EXPORT_SYMBOL(ip_tunnel_encap_add_ops);
int ip_tunnel_encap_del_ops(const struct ip_tunnel_encap_ops *ops,
unsigned int num)
{
int ret;
ret = (cmpxchg((const struct ip_tunnel_encap_ops **)
&iptun_encaps[num],
ops, NULL) == ops) ? 0 : -1;
synchronize_net();
return ret;
}
EXPORT_SYMBOL(ip_tunnel_encap_del_ops);
int ip_tunnel_encap_setup(struct ip_tunnel *t,
struct ip_tunnel_encap *ipencap)
{
@ -534,18 +561,19 @@ EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
int ip_tunnel_encap(struct sk_buff *skb, struct ip_tunnel *t,
u8 *protocol, struct flowi4 *fl4)
{
switch (t->encap.type) {
case TUNNEL_ENCAP_NONE:
const struct ip_tunnel_encap_ops *ops;
int ret = -EINVAL;
if (t->encap.type == TUNNEL_ENCAP_NONE)
return 0;
#if IS_ENABLED(CONFIG_NET_FOU)
case TUNNEL_ENCAP_FOU:
return fou_build_header(skb, &t->encap, protocol, fl4);
case TUNNEL_ENCAP_GUE:
return gue_build_header(skb, &t->encap, protocol, fl4);
#endif
default:
return -EINVAL;
}
rcu_read_lock();
ops = rcu_dereference(iptun_encaps[t->encap.type]);
if (likely(ops && ops->build_header))
ret = ops->build_header(skb, &t->encap, protocol, fl4);
rcu_read_unlock();
return ret;
}
EXPORT_SYMBOL(ip_tunnel_encap);