1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17#include <linux/module.h>
18#include <linux/random.h>
19
20#include <net/addrconf.h>
21#include <net/inet_connection_sock.h>
22#include <net/inet_hashtables.h>
23#include <net/inet6_hashtables.h>
24#include <net/secure_seq.h>
25#include <net/ip.h>
26#include <net/sock_reuseport.h>
27
28u32 inet6_ehashfn(const struct net *net,
29 const struct in6_addr *laddr, const u16 lport,
30 const struct in6_addr *faddr, 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
48
49
50
51
52
53struct sock *__inet6_lookup_established(struct net *net,
54 struct inet_hashinfo *hashinfo,
55 const struct in6_addr *saddr,
56 const __be16 sport,
57 const struct in6_addr *daddr,
58 const u16 hnum,
59 const int dif)
60{
61 struct sock *sk;
62 const struct hlist_nulls_node *node;
63 const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
64
65
66
67 unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
68 unsigned int slot = hash & hashinfo->ehash_mask;
69 struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
70
71
72begin:
73 sk_nulls_for_each_rcu(sk, node, &head->chain) {
74 if (sk->sk_hash != hash)
75 continue;
76 if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif))
77 continue;
78 if (unlikely(!atomic_inc_not_zero(&sk->sk_refcnt)))
79 goto out;
80
81 if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif))) {
82 sock_gen_put(sk);
83 goto begin;
84 }
85 goto found;
86 }
87 if (get_nulls_value(node) != slot)
88 goto begin;
89out:
90 sk = NULL;
91found:
92 return sk;
93}
94EXPORT_SYMBOL(__inet6_lookup_established);
95
96static inline int compute_score(struct sock *sk, struct net *net,
97 const unsigned short hnum,
98 const struct in6_addr *daddr,
99 const int dif)
100{
101 int score = -1;
102
103 if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
104 sk->sk_family == PF_INET6) {
105
106 score = 1;
107 if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
108 if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
109 return -1;
110 score++;
111 }
112 if (sk->sk_bound_dev_if) {
113 if (sk->sk_bound_dev_if != dif)
114 return -1;
115 score++;
116 }
117 if (sk->sk_incoming_cpu == raw_smp_processor_id())
118 score++;
119 }
120 return score;
121}
122
123
124struct sock *inet6_lookup_listener(struct net *net,
125 struct inet_hashinfo *hashinfo,
126 struct sk_buff *skb, int doff,
127 const struct in6_addr *saddr,
128 const __be16 sport, const struct in6_addr *daddr,
129 const unsigned short hnum, const int dif)
130{
131 unsigned int hash = inet_lhashfn(net, hnum);
132 struct inet_listen_hashbucket *ilb = &hashinfo->listening_hash[hash];
133 int score, hiscore = 0, matches = 0, reuseport = 0;
134 struct sock *sk, *result = NULL;
135 u32 phash = 0;
136
137 sk_for_each(sk, &ilb->head) {
138 score = compute_score(sk, net, hnum, daddr, dif);
139 if (score > hiscore) {
140 reuseport = sk->sk_reuseport;
141 if (reuseport) {
142 phash = inet6_ehashfn(net, daddr, hnum,
143 saddr, sport);
144 result = reuseport_select_sock(sk, phash,
145 skb, doff);
146 if (result)
147 return result;
148 matches = 1;
149 }
150 result = sk;
151 hiscore = score;
152 } else if (score == hiscore && reuseport) {
153 matches++;
154 if (reciprocal_scale(phash, matches) == 0)
155 result = sk;
156 phash = next_pseudo_random32(phash);
157 }
158 }
159 return result;
160}
161EXPORT_SYMBOL_GPL(inet6_lookup_listener);
162
163struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
164 struct sk_buff *skb, int doff,
165 const struct in6_addr *saddr, const __be16 sport,
166 const struct in6_addr *daddr, const __be16 dport,
167 const int dif)
168{
169 struct sock *sk;
170 bool refcounted;
171
172 sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
173 ntohs(dport), dif, &refcounted);
174 if (sk && !refcounted && !atomic_inc_not_zero(&sk->sk_refcnt))
175 sk = NULL;
176 return sk;
177}
178EXPORT_SYMBOL_GPL(inet6_lookup);
179
180static int __inet6_check_established(struct inet_timewait_death_row *death_row,
181 struct sock *sk, const __u16 lport,
182 struct inet_timewait_sock **twp)
183{
184 struct inet_hashinfo *hinfo = death_row->hashinfo;
185 struct inet_sock *inet = inet_sk(sk);
186 const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
187 const struct in6_addr *saddr = &sk->sk_v6_daddr;
188 const int dif = sk->sk_bound_dev_if;
189 const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
190 struct net *net = sock_net(sk);
191 const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
192 inet->inet_dport);
193 struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
194 spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
195 struct sock *sk2;
196 const struct hlist_nulls_node *node;
197 struct inet_timewait_sock *tw = NULL;
198
199 spin_lock(lock);
200
201 sk_nulls_for_each(sk2, node, &head->chain) {
202 if (sk2->sk_hash != hash)
203 continue;
204
205 if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports, dif))) {
206 if (sk2->sk_state == TCP_TIME_WAIT) {
207 tw = inet_twsk(sk2);
208 if (twsk_unique(sk, sk2, twp))
209 break;
210 }
211 goto not_unique;
212 }
213 }
214
215
216
217
218 inet->inet_num = lport;
219 inet->inet_sport = htons(lport);
220 sk->sk_hash = hash;
221 WARN_ON(!sk_unhashed(sk));
222 __sk_nulls_add_node_rcu(sk, &head->chain);
223 if (tw) {
224 sk_nulls_del_node_init_rcu((struct sock *)tw);
225 __NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
226 }
227 spin_unlock(lock);
228 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
229
230 if (twp) {
231 *twp = tw;
232 } else if (tw) {
233
234 inet_twsk_deschedule_put(tw);
235 }
236 return 0;
237
238not_unique:
239 spin_unlock(lock);
240 return -EADDRNOTAVAIL;
241}
242
243static u32 inet6_sk_port_offset(const struct sock *sk)
244{
245 const struct inet_sock *inet = inet_sk(sk);
246
247 return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
248 sk->sk_v6_daddr.s6_addr32,
249 inet->inet_dport);
250}
251
252int inet6_hash_connect(struct inet_timewait_death_row *death_row,
253 struct sock *sk)
254{
255 u32 port_offset = 0;
256
257 if (!inet_sk(sk)->inet_num)
258 port_offset = inet6_sk_port_offset(sk);
259 return __inet_hash_connect(death_row, sk, port_offset,
260 __inet6_check_established);
261}
262EXPORT_SYMBOL_GPL(inet6_hash_connect);
263
264int inet6_hash(struct sock *sk)
265{
266 if (sk->sk_state != TCP_CLOSE) {
267 local_bh_disable();
268 __inet_hash(sk, NULL, ipv6_rcv_saddr_equal);
269 local_bh_enable();
270 }
271
272 return 0;
273}
274EXPORT_SYMBOL_GPL(inet6_hash);
275
276
277
278
279
280
281
282int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
283 bool match_wildcard)
284{
285 const struct in6_addr *sk2_rcv_saddr6 = inet6_rcv_saddr(sk2);
286 int sk2_ipv6only = inet_v6_ipv6only(sk2);
287 int addr_type = ipv6_addr_type(&sk->sk_v6_rcv_saddr);
288 int addr_type2 = sk2_rcv_saddr6 ? ipv6_addr_type(sk2_rcv_saddr6) : IPV6_ADDR_MAPPED;
289
290
291 if (addr_type == IPV6_ADDR_MAPPED && addr_type2 == IPV6_ADDR_MAPPED) {
292 if (!sk2_ipv6only) {
293 if (sk->sk_rcv_saddr == sk2->sk_rcv_saddr)
294 return 1;
295 if (!sk->sk_rcv_saddr || !sk2->sk_rcv_saddr)
296 return match_wildcard;
297 }
298 return 0;
299 }
300
301 if (addr_type == IPV6_ADDR_ANY && addr_type2 == IPV6_ADDR_ANY)
302 return 1;
303
304 if (addr_type2 == IPV6_ADDR_ANY && match_wildcard &&
305 !(sk2_ipv6only && addr_type == IPV6_ADDR_MAPPED))
306 return 1;
307
308 if (addr_type == IPV6_ADDR_ANY && match_wildcard &&
309 !(ipv6_only_sock(sk) && addr_type2 == IPV6_ADDR_MAPPED))
310 return 1;
311
312 if (sk2_rcv_saddr6 &&
313 ipv6_addr_equal(&sk->sk_v6_rcv_saddr, sk2_rcv_saddr6))
314 return 1;
315
316 return 0;
317}
318EXPORT_SYMBOL_GPL(ipv6_rcv_saddr_equal);
319