Commit 1b29a730 authored by Philo Lu's avatar Philo Lu Committed by David S. Miller
Browse files

ipv6/udp: Add 4-tuple hash for connected socket 



Implement ipv6 udp hash4 like that in ipv4. The major difference is that
the hash value should be calculated with udp6_ehashfn(). Besides,
ipv4-mapped ipv6 address is handled before hash() and rehash(). Export
udp_ehashfn because now we use it in udpv6 rehash.

Core procedures of hash/unhash/rehash are same as ipv4, and udpv4 and
udpv6 share the same udptable, so some functions in ipv4 hash4 can also
be shared.

Co-developed-by: default avatarCambda Zhu <cambda@linux.alibaba.com>
Signed-off-by: default avatarCambda Zhu <cambda@linux.alibaba.com>
Co-developed-by: default avatarFred Chen <fred.cc@alibaba-inc.com>
Signed-off-by: default avatarFred Chen <fred.cc@alibaba-inc.com>
Co-developed-by: default avatarYubing Qiu <yubing.qiuyubing@alibaba-inc.com>
Signed-off-by: default avatarYubing Qiu <yubing.qiuyubing@alibaba-inc.com>
Signed-off-by: default avatarPhilo Lu <lulie@linux.alibaba.com>
Acked-by: default avatarWillem de Bruijn <willemb@google.com>
Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 78c91ae2

include/net/udp.h

+2 −0
Original line number Diff line number Diff line
@@ -303,6 +303,8 @@ static inline int udp_lib_hash(struct sock *sk) 


void udp_lib_unhash(struct sock *sk);

void udp_lib_rehash(struct sock *sk, u16 new_hash, u16 new_hash4);

u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport,

		const __be32 faddr, const __be16 fport);



static inline void udp_lib_close(struct sock *sk, long timeout)

{

net/ipv4/udp.c

+1 −1
Original line number Diff line number Diff line
@@ -410,7 +410,6 @@ static int compute_score(struct sock *sk, const struct net *net, 
	return score;

}



INDIRECT_CALLABLE_SCOPE

u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport,

		const __be32 faddr, const __be16 fport)

{
@@ -419,6 +418,7 @@ u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport, 
	return __inet_ehashfn(laddr, lport, faddr, fport,

			      udp_ehash_secret + net_hash_mix(net));

}

EXPORT_SYMBOL(udp_ehashfn);



/* called with rcu_read_lock() */

static struct sock *udp4_lib_lookup2(const struct net *net,

net/ipv6/udp.c

+100 −2
Original line number Diff line number Diff line
@@ -110,8 +110,19 @@ void udp_v6_rehash(struct sock *sk) 
	u16 new_hash = ipv6_portaddr_hash(sock_net(sk),

					  &sk->sk_v6_rcv_saddr,

					  inet_sk(sk)->inet_num);

	u16 new_hash4;



	udp_lib_rehash(sk, new_hash, 0); /* 4-tuple hash not implemented */

	if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) {

		new_hash4 = udp_ehashfn(sock_net(sk),

					sk->sk_rcv_saddr, sk->sk_num,

					sk->sk_daddr, sk->sk_dport);

	} else {

		new_hash4 = udp6_ehashfn(sock_net(sk),

					 &sk->sk_v6_rcv_saddr, sk->sk_num,

					 &sk->sk_v6_daddr, sk->sk_dport);

	}



	udp_lib_rehash(sk, new_hash, new_hash4);

}



static int compute_score(struct sock *sk, const struct net *net,
@@ -216,6 +227,74 @@ static struct sock *udp6_lib_lookup2(const struct net *net, 
	return result;

}



#if IS_ENABLED(CONFIG_BASE_SMALL)

static struct sock *udp6_lib_lookup4(const struct net *net,

				     const struct in6_addr *saddr, __be16 sport,

				     const struct in6_addr *daddr,

				     unsigned int hnum, int dif, int sdif,

				     struct udp_table *udptable)

{

	return NULL;

}



static void udp6_hash4(struct sock *sk)

{

}

#else /* !CONFIG_BASE_SMALL */

static struct sock *udp6_lib_lookup4(const struct net *net,

				     const struct in6_addr *saddr, __be16 sport,

				     const struct in6_addr *daddr,

				     unsigned int hnum, int dif, int sdif,

				     struct udp_table *udptable)

{

	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);

	const struct hlist_nulls_node *node;

	struct udp_hslot *hslot4;

	unsigned int hash4, slot;

	struct udp_sock *up;

	struct sock *sk;



	hash4 = udp6_ehashfn(net, daddr, hnum, saddr, sport);

	slot = hash4 & udptable->mask;

	hslot4 = &udptable->hash4[slot];



begin:

	udp_lrpa_for_each_entry_rcu(up, node, &hslot4->nulls_head) {

		sk = (struct sock *)up;

		if (inet6_match(net, sk, saddr, daddr, ports, dif, sdif))

			return sk;

	}



	/* if the nulls value we got at the end of this lookup is not the

	 * expected one, we must restart lookup. We probably met an item that

	 * was moved to another chain due to rehash.

	 */

	if (get_nulls_value(node) != slot)

		goto begin;



	return NULL;

}



static void udp6_hash4(struct sock *sk)

{

	struct net *net = sock_net(sk);

	unsigned int hash;



	if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr)) {

		udp4_hash4(sk);

		return;

	}



	if (sk_unhashed(sk) || ipv6_addr_any(&sk->sk_v6_rcv_saddr))

		return;



	hash = udp6_ehashfn(net, &sk->sk_v6_rcv_saddr, sk->sk_num,

			    &sk->sk_v6_daddr, sk->sk_dport);



	udp_lib_hash4(sk, hash);

}

#endif /* CONFIG_BASE_SMALL */



/* rcu_read_lock() must be held */

struct sock *__udp6_lib_lookup(const struct net *net,

			       const struct in6_addr *saddr, __be16 sport,
@@ -231,6 +310,13 @@ struct sock *__udp6_lib_lookup(const struct net *net, 
	hash2 = ipv6_portaddr_hash(net, daddr, hnum);

	hslot2 = udp_hashslot2(udptable, hash2);



	if (udp_has_hash4(hslot2)) {

		result = udp6_lib_lookup4(net, saddr, sport, daddr, hnum,

					  dif, sdif, udptable);

		if (result) /* udp6_lib_lookup4 return sk or NULL */

			return result;

	}



	/* Lookup connected or non-wildcard sockets */

	result = udp6_lib_lookup2(net, saddr, sport,

				  daddr, hnum, dif, sdif,
@@ -1166,6 +1252,18 @@ static int udpv6_pre_connect(struct sock *sk, struct sockaddr *uaddr, 
	return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len);

}



static int udpv6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)

{

	int res;



	lock_sock(sk);

	res = __ip6_datagram_connect(sk, uaddr, addr_len);

	if (!res)

		udp6_hash4(sk);

	release_sock(sk);

	return res;

}



/**

 *	udp6_hwcsum_outgoing  -  handle outgoing HW checksumming

 *	@sk:	socket we are sending on
@@ -1761,7 +1859,7 @@ struct proto udpv6_prot = { 
	.owner			= THIS_MODULE,

	.close			= udp_lib_close,

	.pre_connect		= udpv6_pre_connect,

	.connect		= ip6_datagram_connect,

	.connect		= udpv6_connect,

	.disconnect		= udp_disconnect,

	.ioctl			= udp_ioctl,

	.init			= udpv6_init_sock,