| /* |
| * 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; |
| struct hlist_nulls_node *node; |
| u32 phash = 0; |
| |
| sk_nulls_for_each(sk, node, &ilb->nulls_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); |