ipv6: Kill ipv6 dependency of icmpv6_send().

Following patch adds icmp-registration module for ipv6.  It allows
ipv6 protocol to register icmp_sender which is used for sending
ipv6 icmp msgs.  This extra layer allows us to kill ipv6 dependency
for sending icmp packets.

This patch also fixes ip_tunnel compilation problem when ip_tunnel
is statically compiled in kernel but ipv6 is module

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Pravin B Shelar 2013-04-25 11:08:30 +00:00 committed by David S. Miller
parent a4c4009f4f
commit 5f5624cf15
4 changed files with 83 additions and 19 deletions

View File

@ -11,9 +11,21 @@ static inline struct icmp6hdr *icmp6_hdr(const struct sk_buff *skb)
#include <linux/netdevice.h>
extern void icmpv6_send(struct sk_buff *skb,
u8 type, u8 code,
__u32 info);
#if IS_ENABLED(CONFIG_IPV6)
extern void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info);
typedef void ip6_icmp_send_t(struct sk_buff *skb, u8 type, u8 code, __u32 info);
extern int inet6_register_icmp_sender(ip6_icmp_send_t *fn);
extern int inet6_unregister_icmp_sender(ip6_icmp_send_t *fn);
#else
static inline void icmpv6_send(struct sk_buff *skb,
u8 type, u8 code, __u32 info)
{
}
#endif
extern int icmpv6_init(void);
extern int icmpv6_err_convert(u8 type, u8 code,

View File

@ -40,7 +40,7 @@ obj-$(CONFIG_IPV6_SIT) += sit.o
obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o
obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o ip6_icmp.o
obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o

View File

@ -123,15 +123,6 @@ static __inline__ void icmpv6_xmit_unlock(struct sock *sk)
spin_unlock_bh(&sk->sk_lock.slock);
}
/*
* Slightly more convenient version of icmpv6_send.
*/
void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
{
icmpv6_send(skb, ICMPV6_PARAMPROB, code, pos);
kfree_skb(skb);
}
/*
* Figure out, may we reply to this packet with icmp error.
*
@ -332,7 +323,7 @@ static struct dst_entry *icmpv6_route_lookup(struct net *net, struct sk_buff *sk
* anycast.
*/
if (((struct rt6_info *)dst)->rt6i_flags & RTF_ANYCAST) {
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: acast source\n");
LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: acast source\n");
dst_release(dst);
return ERR_PTR(-EINVAL);
}
@ -381,7 +372,7 @@ relookup_failed:
/*
* Send an ICMP message in response to a packet in error
*/
void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
static void icmp6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
{
struct net *net = dev_net(skb->dev);
struct inet6_dev *idev = NULL;
@ -406,7 +397,7 @@ void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
/*
* Make sure we respect the rules
* i.e. RFC 1885 2.4(e)
* Rule (e.1) is enforced by not using icmpv6_send
* Rule (e.1) is enforced by not using icmp6_send
* in any code that processes icmp errors.
*/
addr_type = ipv6_addr_type(&hdr->daddr);
@ -444,7 +435,7 @@ void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
* and anycast addresses will be checked later.
*/
if ((addr_type == IPV6_ADDR_ANY) || (addr_type & IPV6_ADDR_MULTICAST)) {
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: addr_any/mcast source\n");
LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: addr_any/mcast source\n");
return;
}
@ -452,7 +443,7 @@ void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
* Never answer to a ICMP packet.
*/
if (is_ineligible(skb)) {
LIMIT_NETDEBUG(KERN_DEBUG "icmpv6_send: no reply to icmp error\n");
LIMIT_NETDEBUG(KERN_DEBUG "icmp6_send: no reply to icmp error\n");
return;
}
@ -529,7 +520,14 @@ out_dst_release:
out:
icmpv6_xmit_unlock(sk);
}
EXPORT_SYMBOL(icmpv6_send);
/* Slightly more convenient version of icmp6_send.
*/
void icmpv6_param_prob(struct sk_buff *skb, u8 code, int pos)
{
icmp6_send(skb, ICMPV6_PARAMPROB, code, pos);
kfree_skb(skb);
}
static void icmpv6_echo_reply(struct sk_buff *skb)
{
@ -885,8 +883,14 @@ int __init icmpv6_init(void)
err = -EAGAIN;
if (inet6_add_protocol(&icmpv6_protocol, IPPROTO_ICMPV6) < 0)
goto fail;
err = inet6_register_icmp_sender(icmp6_send);
if (err)
goto sender_reg_err;
return 0;
sender_reg_err:
inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
fail:
pr_err("Failed to register ICMP6 protocol\n");
unregister_pernet_subsys(&icmpv6_sk_ops);
@ -895,6 +899,7 @@ fail:
void icmpv6_cleanup(void)
{
inet6_unregister_icmp_sender(icmp6_send);
unregister_pernet_subsys(&icmpv6_sk_ops);
inet6_del_protocol(&icmpv6_protocol, IPPROTO_ICMPV6);
}

47
net/ipv6/ip6_icmp.c Normal file
View File

@ -0,0 +1,47 @@
#include <linux/export.h>
#include <linux/icmpv6.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/spinlock.h>
#include <net/ipv6.h>
#if IS_ENABLED(CONFIG_IPV6)
static ip6_icmp_send_t __rcu *ip6_icmp_send;
int inet6_register_icmp_sender(ip6_icmp_send_t *fn)
{
return (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, NULL, fn) == NULL) ?
0 : -EBUSY;
}
EXPORT_SYMBOL(inet6_register_icmp_sender);
int inet6_unregister_icmp_sender(ip6_icmp_send_t *fn)
{
int ret;
ret = (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, fn, NULL) == fn) ?
0 : -EINVAL;
synchronize_net();
return ret;
}
EXPORT_SYMBOL(inet6_unregister_icmp_sender);
void icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info)
{
ip6_icmp_send_t *send;
rcu_read_lock();
send = rcu_dereference(ip6_icmp_send);
if (!send)
goto out;
send(skb, type, code, info);
out:
rcu_read_unlock();
}
EXPORT_SYMBOL(icmpv6_send);
#endif