Root/
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
3 | * operating system. INET is implemented using the BSD Socket |
4 | * interface as the means of communication with the user level. |
5 | * |
6 | * Generic INET6 transport hashtables |
7 | * |
8 | * Authors: Lotsa people, from code originally in tcp, generalised here |
9 | * by Arnaldo Carvalho de Melo <acme@mandriva.com> |
10 | * |
11 | * This program is free software; you can redistribute it and/or |
12 | * modify it under the terms of the GNU General Public License |
13 | * as published by the Free Software Foundation; either version |
14 | * 2 of the License, or (at your option) any later version. |
15 | */ |
16 | |
17 | #include <linux/module.h> |
18 | #include <linux/random.h> |
19 | |
20 | #include <net/inet_connection_sock.h> |
21 | #include <net/inet_hashtables.h> |
22 | #include <net/inet6_hashtables.h> |
23 | #include <net/secure_seq.h> |
24 | #include <net/ip.h> |
25 | |
26 | static unsigned int inet6_ehashfn(struct net *net, |
27 | const struct in6_addr *laddr, |
28 | const u16 lport, |
29 | const struct in6_addr *faddr, |
30 | const __be16 fport) |
31 | { |
32 | static u32 inet6_ehash_secret __read_mostly; |
33 | static u32 ipv6_hash_secret __read_mostly; |
34 | |
35 | u32 lhash, fhash; |
36 | |
37 | net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret)); |
38 | net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret)); |
39 | |
40 | lhash = (__force u32)laddr->s6_addr32[3]; |
41 | fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret); |
42 | |
43 | return __inet6_ehashfn(lhash, lport, fhash, fport, |
44 | inet6_ehash_secret + net_hash_mix(net)); |
45 | } |
46 | |
47 | static int inet6_sk_ehashfn(const struct sock *sk) |
48 | { |
49 | const struct inet_sock *inet = inet_sk(sk); |
50 | const struct in6_addr *laddr = &sk->sk_v6_rcv_saddr; |
51 | const struct in6_addr *faddr = &sk->sk_v6_daddr; |
52 | const __u16 lport = inet->inet_num; |
53 | const __be16 fport = inet->inet_dport; |
54 | struct net *net = sock_net(sk); |
55 | |
56 | return inet6_ehashfn(net, laddr, lport, faddr, fport); |
57 | } |
58 | |
59 | int __inet6_hash(struct sock *sk, struct inet_timewait_sock *tw) |
60 | { |
61 | struct inet_hashinfo *hashinfo = sk->sk_prot->h.hashinfo; |
62 | int twrefcnt = 0; |
63 | |
64 | WARN_ON(!sk_unhashed(sk)); |
65 | |
66 | if (sk->sk_state == TCP_LISTEN) { |
67 | struct inet_listen_hashbucket *ilb; |
68 | |
69 | ilb = &hashinfo->listening_hash[inet_sk_listen_hashfn(sk)]; |
70 | spin_lock(&ilb->lock); |
71 | __sk_nulls_add_node_rcu(sk, &ilb->head); |
72 | spin_unlock(&ilb->lock); |
73 | } else { |
74 | unsigned int hash; |
75 | struct hlist_nulls_head *list; |
76 | spinlock_t *lock; |
77 | |
78 | sk->sk_hash = hash = inet6_sk_ehashfn(sk); |
79 | list = &inet_ehash_bucket(hashinfo, hash)->chain; |
80 | lock = inet_ehash_lockp(hashinfo, hash); |
81 | spin_lock(lock); |
82 | __sk_nulls_add_node_rcu(sk, list); |
83 | if (tw) { |
84 | WARN_ON(sk->sk_hash != tw->tw_hash); |
85 | twrefcnt = inet_twsk_unhash(tw); |
86 | } |
87 | spin_unlock(lock); |
88 | } |
89 | |
90 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
91 | return twrefcnt; |
92 | } |
93 | EXPORT_SYMBOL(__inet6_hash); |
94 | |
95 | /* |
96 | * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so |
97 | * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM |
98 | * |
99 | * The sockhash lock must be held as a reader here. |
100 | */ |
101 | struct sock *__inet6_lookup_established(struct net *net, |
102 | struct inet_hashinfo *hashinfo, |
103 | const struct in6_addr *saddr, |
104 | const __be16 sport, |
105 | const struct in6_addr *daddr, |
106 | const u16 hnum, |
107 | const int dif) |
108 | { |
109 | struct sock *sk; |
110 | const struct hlist_nulls_node *node; |
111 | const __portpair ports = INET_COMBINED_PORTS(sport, hnum); |
112 | /* Optimize here for direct hit, only listening connections can |
113 | * have wildcards anyways. |
114 | */ |
115 | unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport); |
116 | unsigned int slot = hash & hashinfo->ehash_mask; |
117 | struct inet_ehash_bucket *head = &hashinfo->ehash[slot]; |
118 | |
119 | |
120 | rcu_read_lock(); |
121 | begin: |
122 | sk_nulls_for_each_rcu(sk, node, &head->chain) { |
123 | if (sk->sk_hash != hash) |
124 | continue; |
125 | if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif)) |
126 | continue; |
127 | if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt))) |
128 | goto out; |
129 | |
130 | if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif))) { |
131 | sock_gen_put(sk); |
132 | goto begin; |
133 | } |
134 | goto found; |
135 | } |
136 | if (get_nulls_value(node) != slot) |
137 | goto begin; |
138 | out: |
139 | sk = NULL; |
140 | found: |
141 | rcu_read_unlock(); |
142 | return sk; |
143 | } |
144 | EXPORT_SYMBOL(__inet6_lookup_established); |
145 | |
146 | static inline int compute_score(struct sock *sk, struct net *net, |
147 | const unsigned short hnum, |
148 | const struct in6_addr *daddr, |
149 | const int dif) |
150 | { |
151 | int score = -1; |
152 | |
153 | if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum && |
154 | sk->sk_family == PF_INET6) { |
155 | |
156 | score = 1; |
157 | if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) { |
158 | if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr)) |
159 | return -1; |
160 | score++; |
161 | } |
162 | if (sk->sk_bound_dev_if) { |
163 | if (sk->sk_bound_dev_if != dif) |
164 | return -1; |
165 | score++; |
166 | } |
167 | } |
168 | return score; |
169 | } |
170 | |
171 | struct sock *inet6_lookup_listener(struct net *net, |
172 | struct inet_hashinfo *hashinfo, const struct in6_addr *saddr, |
173 | const __be16 sport, const struct in6_addr *daddr, |
174 | const unsigned short hnum, const int dif) |
175 | { |
176 | struct sock *sk; |
177 | const struct hlist_nulls_node *node; |
178 | struct sock *result; |
179 | int score, hiscore, matches = 0, reuseport = 0; |
180 | u32 phash = 0; |
181 | unsigned int hash = inet_lhashfn(net, hnum); |
182 | struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash]; |
183 | |
184 | rcu_read_lock(); |
185 | begin: |
186 | result = NULL; |
187 | hiscore = 0; |
188 | sk_nulls_for_each(sk, node, &ilb->head) { |
189 | score = compute_score(sk, net, hnum, daddr, dif); |
190 | if (score > hiscore) { |
191 | hiscore = score; |
192 | result = sk; |
193 | reuseport = sk->sk_reuseport; |
194 | if (reuseport) { |
195 | phash = inet6_ehashfn(net, daddr, hnum, |
196 | saddr, sport); |
197 | matches = 1; |
198 | } |
199 | } else if (score == hiscore && reuseport) { |
200 | matches++; |
201 | if (((u64)phash * matches) >> 32 == 0) |
202 | result = sk; |
203 | phash = next_pseudo_random32(phash); |
204 | } |
205 | } |
206 | /* |
207 | * if the nulls value we got at the end of this lookup is |
208 | * not the expected one, we must restart lookup. |
209 | * We probably met an item that was moved to another chain. |
210 | */ |
211 | if (get_nulls_value(node) != hash + LISTENING_NULLS_BASE) |
212 | goto begin; |
213 | if (result) { |
214 | if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt))) |
215 | result = NULL; |
216 | else if (unlikely(compute_score(result, net, hnum, daddr, |
217 | dif) < hiscore)) { |
218 | sock_put(result); |
219 | goto begin; |
220 | } |
221 | } |
222 | rcu_read_unlock(); |
223 | return result; |
224 | } |
225 | |
226 | EXPORT_SYMBOL_GPL(inet6_lookup_listener); |
227 | |
228 | struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo, |
229 | const struct in6_addr *saddr, const __be16 sport, |
230 | const struct in6_addr *daddr, const __be16 dport, |
231 | const int dif) |
232 | { |
233 | struct sock *sk; |
234 | |
235 | local_bh_disable(); |
236 | sk = __inet6_lookup(net, hashinfo, saddr, sport, daddr, ntohs(dport), dif); |
237 | local_bh_enable(); |
238 | |
239 | return sk; |
240 | } |
241 | |
242 | EXPORT_SYMBOL_GPL(inet6_lookup); |
243 | |
244 | static int __inet6_check_established(struct inet_timewait_death_row *death_row, |
245 | struct sock *sk, const __u16 lport, |
246 | struct inet_timewait_sock **twp) |
247 | { |
248 | struct inet_hashinfo *hinfo = death_row->hashinfo; |
249 | struct inet_sock *inet = inet_sk(sk); |
250 | const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr; |
251 | const struct in6_addr *saddr = &sk->sk_v6_daddr; |
252 | const int dif = sk->sk_bound_dev_if; |
253 | const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport); |
254 | struct net *net = sock_net(sk); |
255 | const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr, |
256 | inet->inet_dport); |
257 | struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash); |
258 | spinlock_t *lock = inet_ehash_lockp(hinfo, hash); |
259 | struct sock *sk2; |
260 | const struct hlist_nulls_node *node; |
261 | struct inet_timewait_sock *tw = NULL; |
262 | int twrefcnt = 0; |
263 | |
264 | spin_lock(lock); |
265 | |
266 | sk_nulls_for_each(sk2, node, &head->chain) { |
267 | if (sk2->sk_hash != hash) |
268 | continue; |
269 | |
270 | if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports, dif))) { |
271 | if (sk2->sk_state == TCP_TIME_WAIT) { |
272 | tw = inet_twsk(sk2); |
273 | if (twsk_unique(sk, sk2, twp)) |
274 | break; |
275 | } |
276 | goto not_unique; |
277 | } |
278 | } |
279 | |
280 | /* Must record num and sport now. Otherwise we will see |
281 | * in hash table socket with a funny identity. |
282 | */ |
283 | inet->inet_num = lport; |
284 | inet->inet_sport = htons(lport); |
285 | sk->sk_hash = hash; |
286 | WARN_ON(!sk_unhashed(sk)); |
287 | __sk_nulls_add_node_rcu(sk, &head->chain); |
288 | if (tw) { |
289 | twrefcnt = inet_twsk_unhash(tw); |
290 | NET_INC_STATS_BH(net, LINUX_MIB_TIMEWAITRECYCLED); |
291 | } |
292 | spin_unlock(lock); |
293 | if (twrefcnt) |
294 | inet_twsk_put(tw); |
295 | sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); |
296 | |
297 | if (twp) { |
298 | *twp = tw; |
299 | } else if (tw) { |
300 | /* Silly. Should hash-dance instead... */ |
301 | inet_twsk_deschedule(tw, death_row); |
302 | |
303 | inet_twsk_put(tw); |
304 | } |
305 | return 0; |
306 | |
307 | not_unique: |
308 | spin_unlock(lock); |
309 | return -EADDRNOTAVAIL; |
310 | } |
311 | |
312 | static inline u32 inet6_sk_port_offset(const struct sock *sk) |
313 | { |
314 | const struct inet_sock *inet = inet_sk(sk); |
315 | |
316 | return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32, |
317 | sk->sk_v6_daddr.s6_addr32, |
318 | inet->inet_dport); |
319 | } |
320 | |
321 | int inet6_hash_connect(struct inet_timewait_death_row *death_row, |
322 | struct sock *sk) |
323 | { |
324 | return __inet_hash_connect(death_row, sk, inet6_sk_port_offset(sk), |
325 | __inet6_check_established, __inet6_hash); |
326 | } |
327 | |
328 | EXPORT_SYMBOL_GPL(inet6_hash_connect); |
329 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9