Skip to content
Snippets Groups Projects
Select Git revision
  • e4cabca54911a6be6f2e80e48fa497c7e19019a5
  • vme-testing default
  • ci-test
  • master
  • remoteproc
  • am625-sk-ov5640
  • pcal6534-upstreaming
  • lps22df-upstreaming
  • msc-upstreaming
  • imx8mp
  • iio/noa1305
  • vme-next
  • vme-next-4.14-rc4
  • v4.14-rc4
  • v4.14-rc3
  • v4.14-rc2
  • v4.14-rc1
  • v4.13
  • vme-next-4.13-rc7
  • v4.13-rc7
  • v4.13-rc6
  • v4.13-rc5
  • v4.13-rc4
  • v4.13-rc3
  • v4.13-rc2
  • v4.13-rc1
  • v4.12
  • v4.12-rc7
  • v4.12-rc6
  • v4.12-rc5
  • v4.12-rc4
  • v4.12-rc3
32 results

inet6_hashtables.c

Blame
  • user avatar
    Craig Gallek authored and David S. Miller committed
    As part of a series to implement faster SO_REUSEPORT lookups,
    commit 086c653f ("sock: struct proto hash function may error")
    added return values to protocol hash functions and
    commit 496611d7 ("inet: create IPv6-equivalent inet_hash function")
    implemented a new hash function for IPv6.  However, the latter does
    not respect the former's convention.
    
    This properly propagates the hash errors in the IPv6 case.
    
    Fixes: 496611d7 ("inet: create IPv6-equivalent inet_hash function")
    Reported-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
    Signed-off-by: default avatarCraig Gallek <kraig@google.com>
    Acked-by: default avatarSoheil Hassas Yeganeh <soheil@google.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    e4cabca5
    History
    inet6_hashtables.c 8.99 KiB
    /*
     * INET		An implementation of the TCP/IP protocol suite for the LINUX
     *		operating system.  INET is implemented using the BSD Socket
     *		interface as the means of communication with the user level.
     *
     *		Generic INET6 transport hashtables
     *
     * Authors:	Lotsa people, from code originally in tcp, generalised here
     *		by Arnaldo Carvalho de Melo <acme@mandriva.com>
     *
     *	This program is free software; you can redistribute it and/or
     *      modify it under the terms of the GNU General Public License
     *      as published by the Free Software Foundation; either version
     *      2 of the License, or (at your option) any later version.
     */
    
    #include <linux/module.h>
    #include <linux/random.h>
    
    #include <net/addrconf.h>
    #include <net/inet_connection_sock.h>
    #include <net/inet_hashtables.h>
    #include <net/inet6_hashtables.h>
    #include <net/secure_seq.h>
    #include <net/ip.h>
    #include <net/sock_reuseport.h>
    
    u32 inet6_ehashfn(const struct net *net,
    		  const struct in6_addr *laddr, const u16 lport,
    		  const struct in6_addr *faddr, const __be16 fport)
    {
    	static u32 inet6_ehash_secret __read_mostly;
    	static u32 ipv6_hash_secret __read_mostly;
    
    	u32 lhash, fhash;
    
    	net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
    	net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
    
    	lhash = (__force u32)laddr->s6_addr32[3];
    	fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
    
    	return __inet6_ehashfn(lhash, lport, fhash, fport,
    			       inet6_ehash_secret + net_hash_mix(net));
    }
    
    /*
     * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
     * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
     *
     * The sockhash lock must be held as a reader here.
     */
    struct sock *__inet6_lookup_established(struct net *net,
    					struct inet_hashinfo *hashinfo,
    					   const struct in6_addr *saddr,
    					   const __be16 sport,
    					   const struct in6_addr *daddr,
    					   const u16 hnum,
    					   const int dif)
    {
    	struct sock *sk;
    	const struct hlist_nulls_node *node;
    	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
    	/* Optimize here for direct hit, only listening connections can
    	 * have wildcards anyways.
    	 */
    	unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
    	unsigned int slot = hash & hashinfo->ehash_mask;
    	struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
    
    
    begin:
    	sk_nulls_for_each_rcu(sk, node, &head->chain) {
    		if (sk->sk_hash != hash)
    			continue;
    		if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif))
    			continue;
    		if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt)))
    			goto out;
    
    		if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif))) {
    			sock_gen_put(sk);
    			goto begin;
    		}
    		goto found;
    	}
    	if (get_nulls_value(node) != slot)
    		goto begin;
    out:
    	sk = NULL;
    found:
    	return sk;
    }
    EXPORT_SYMBOL(__inet6_lookup_established);
    
    static inline int compute_score(struct sock *sk, struct net *net,
    				const unsigned short hnum,
    				const struct in6_addr *daddr,
    				const int dif, bool exact_dif)
    {
    	int score = -1;
    
    	if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
    	    sk->sk_family == PF_INET6) {
    
    		score = 1;
    		if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
    			if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
    				return -1;
    			score++;
    		}
    		if (sk->sk_bound_dev_if || exact_dif) {
    			if (sk->sk_bound_dev_if != dif)
    				return -1;
    			score++;
    		}
    		if (sk->sk_incoming_cpu == raw_smp_processor_id())
    			score++;
    	}
    	return score;
    }
    
    /* called with rcu_read_lock() */
    struct sock *inet6_lookup_listener(struct net *net,
    		struct inet_hashinfo *hashinfo,
    		struct sk_buff *skb, int doff,
    		const struct in6_addr *saddr,
    		const __be16 sport, const struct in6_addr *daddr,
    		const unsigned short hnum, const int dif)
    {
    	unsigned int hash = inet_lhashfn(net, hnum);
    	struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
    	int score, hiscore = 0, matches = 0, reuseport = 0;
    	bool exact_dif = inet6_exact_dif_match(net, skb);
    	struct sock *sk, *result = NULL;
    	u32 phash = 0;
    
    	sk_for_each(sk, &ilb->head) {
    		score = compute_score(sk, net, hnum, daddr, dif, exact_dif);
    		if (score > hiscore) {
    			reuseport = sk->sk_reuseport;
    			if (reuseport) {
    				phash = inet6_ehashfn(net, daddr, hnum,
    						      saddr, sport);
    				result = reuseport_select_sock(sk, phash,
    							       skb, doff);
    				if (result)
    					return result;
    				matches = 1;
    			}
    			result = sk;
    			hiscore = score;
    		} else if (score == hiscore && reuseport) {
    			matches++;
    			if (reciprocal_scale(phash, matches) == 0)
    				result = sk;
    			phash = next_pseudo_random32(phash);
    		}
    	}
    	return result;
    }
    EXPORT_SYMBOL_GPL(inet6_lookup_listener);
    
    struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
    			  struct sk_buff *skb, int doff,
    			  const struct in6_addr *saddr, const __be16 sport,
    			  const struct in6_addr *daddr, const __be16 dport,
    			  const int dif)
    {
    	struct sock *sk;
    	bool refcounted;
    
    	sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
    			    ntohs(dport), dif, &refcounted);
    	if (sk && !refcounted && !atomic_inc_not_zero(&sk->sk_refcnt))
    		sk = NULL;
    	return sk;
    }
    EXPORT_SYMBOL_GPL(inet6_lookup);
    
    static int __inet6_check_established(struct inet_timewait_death_row *death_row,
    				     struct sock *sk, const __u16 lport,
    				     struct inet_timewait_sock **twp)
    {
    	struct inet_hashinfo *hinfo = death_row->hashinfo;
    	struct inet_sock *inet = inet_sk(sk);
    	const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
    	const struct in6_addr *saddr = &sk->sk_v6_daddr;
    	const int dif = sk->sk_bound_dev_if;
    	const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
    	struct net *net = sock_net(sk);
    	const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
    						inet->inet_dport);
    	struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
    	spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
    	struct sock *sk2;
    	const struct hlist_nulls_node *node;
    	struct inet_timewait_sock *tw = NULL;
    
    	spin_lock(lock);
    
    	sk_nulls_for_each(sk2, node, &head->chain) {
    		if (sk2->sk_hash != hash)
    			continue;
    
    		if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports, dif))) {
    			if (sk2->sk_state == TCP_TIME_WAIT) {
    				tw = inet_twsk(sk2);
    				if (twsk_unique(sk, sk2, twp))
    					break;
    			}
    			goto not_unique;
    		}
    	}
    
    	/* Must record num and sport now. Otherwise we will see
    	 * in hash table socket with a funny identity.
    	 */
    	inet->inet_num = lport;
    	inet->inet_sport = htons(lport);
    	sk->sk_hash = hash;
    	WARN_ON(!sk_unhashed(sk));
    	__sk_nulls_add_node_rcu(sk, &head->chain);
    	if (tw) {
    		sk_nulls_del_node_init_rcu((struct sock *)tw);
    		__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
    	}
    	spin_unlock(lock);
    	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
    
    	if (twp) {
    		*twp = tw;
    	} else if (tw) {
    		/* Silly. Should hash-dance instead... */
    		inet_twsk_deschedule_put(tw);
    	}
    	return 0;
    
    not_unique:
    	spin_unlock(lock);
    	return -EADDRNOTAVAIL;
    }
    
    static u32 inet6_sk_port_offset(const struct sock *sk)
    {
    	const struct inet_sock *inet = inet_sk(sk);
    
    	return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
    					  sk->sk_v6_daddr.s6_addr32,
    					  inet->inet_dport);
    }
    
    int inet6_hash_connect(struct inet_timewait_death_row *death_row,
    		       struct sock *sk)
    {
    	u32 port_offset = 0;
    
    	if (!inet_sk(sk)->inet_num)
    		port_offset = inet6_sk_port_offset(sk);
    	return __inet_hash_connect(death_row, sk, port_offset,
    				   __inet6_check_established);
    }
    EXPORT_SYMBOL_GPL(inet6_hash_connect);
    
    int inet6_hash(struct sock *sk)
    {
    	int err = 0;
    
    	if (sk->sk_state != TCP_CLOSE) {
    		local_bh_disable();
    		err = __inet_hash(sk, NULL, ipv6_rcv_saddr_equal);
    		local_bh_enable();
    	}
    
    	return err;
    }
    EXPORT_SYMBOL_GPL(inet6_hash);
    
    /* match_wildcard == true:  IPV6_ADDR_ANY equals to any IPv6 addresses if IPv6
     *                          only, and any IPv4 addresses if not IPv6 only
     * match_wildcard == false: addresses must be exactly the same, i.e.
     *                          IPV6_ADDR_ANY only equals to IPV6_ADDR_ANY,
     *                          and 0.0.0.0 equals to 0.0.0.0 only
     */
    int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
    			 bool match_wildcard)
    {
    	const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
    	int sk2_ipv6only = inet_v6_ipv6only(sk2);
    	int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
    	int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
    
    	/* if both are mapped, treat as IPv4 */
    	if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) {
    		if (!sk2_ipv6only) {
    			if (sk->sk_rcv_saddr == sk2->sk_rcv_saddr)
    				return 1;
    			if (!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr)
    				return match_wildcard;
    		}
    		return 0;
    	}
    
    	if (addr_type == IPV6_ADDR_ANY && addr_type2 == IPV6_ADDR_ANY)
    		return 1;
    
    	if (addr_type2 == IPV6_ADDR_ANY && match_wildcard &&
    	    !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
    		return 1;
    
    	if (addr_type == IPV6_ADDR_ANY && match_wildcard &&
    	    !(ipv6_only_sock(sk) && addr_type2 == IPV6_ADDR_MAPPED))
    		return 1;
    
    	if (sk2_rcv_saddr6 &&
    	    ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
    		return 1;
    
    	return 0;
    }
    EXPORT_SYMBOL_GPL(ipv6_rcv_saddr_equal);