1/*
2 * Copyright (c) 2006, 2019 Oracle and/or its affiliates. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 *
32 */
33#include <linux/kernel.h>
34#include <net/sock.h>
35#include <linux/in.h>
36#include <linux/ipv6.h>
37#include <linux/if_arp.h>
38#include <linux/jhash.h>
39#include <linux/ratelimit.h>
40#include "rds.h"
41
42static struct rhashtable bind_hash_table;
43
44static const struct rhashtable_params ht_parms = {
45 .nelem_hint = 768,
46 .key_len = RDS_BOUND_KEY_LEN,
47 .key_offset = offsetof(struct rds_sock, rs_bound_key),
48 .head_offset = offsetof(struct rds_sock, rs_bound_node),
49 .max_size = 16384,
50 .min_size = 1024,
51};
52
53/* Create a key for the bind hash table manipulation. Port is in network byte
54 * order.
55 */
56static inline void __rds_create_bind_key(u8 *key, const struct in6_addr *addr,
57 __be16 port, __u32 scope_id)
58{
59 memcpy(key, addr, sizeof(*addr));
60 key += sizeof(*addr);
61 memcpy(key, &port, sizeof(port));
62 key += sizeof(port);
63 memcpy(key, &scope_id, sizeof(scope_id));
64}
65
66/*
67 * Return the rds_sock bound at the given local address.
68 *
69 * The rx path can race with rds_release. We notice if rds_release() has
70 * marked this socket and don't return a rs ref to the rx path.
71 */
72struct rds_sock *rds_find_bound(const struct in6_addr *addr, __be16 port,
73 __u32 scope_id)
74{
75 u8 key[RDS_BOUND_KEY_LEN];
76 struct rds_sock *rs;
77
78 __rds_create_bind_key(key, addr, port, scope_id);
79 rcu_read_lock();
80 rs = rhashtable_lookup(ht: &bind_hash_table, key, params: ht_parms);
81 if (rs && (sock_flag(sk: rds_rs_to_sk(rs), flag: SOCK_DEAD) ||
82 !refcount_inc_not_zero(r: &rds_rs_to_sk(rs)->sk_refcnt)))
83 rs = NULL;
84
85 rcu_read_unlock();
86
87 rdsdebug("returning rs %p for %pI6c:%u\n", rs, addr,
88 ntohs(port));
89
90 return rs;
91}
92
93/* returns -ve errno or +ve port */
94static int rds_add_bound(struct rds_sock *rs, const struct in6_addr *addr,
95 __be16 *port, __u32 scope_id)
96{
97 int ret = -EADDRINUSE;
98 u16 rover, last;
99 u8 key[RDS_BOUND_KEY_LEN];
100
101 if (*port != 0) {
102 rover = be16_to_cpu(*port);
103 if (rover == RDS_FLAG_PROBE_PORT)
104 return -EINVAL;
105 last = rover;
106 } else {
107 rover = max_t(u16, get_random_u16(), 2);
108 last = rover - 1;
109 }
110
111 do {
112 if (rover == 0)
113 rover++;
114
115 if (rover == RDS_FLAG_PROBE_PORT)
116 continue;
117 __rds_create_bind_key(key, addr, cpu_to_be16(rover),
118 scope_id);
119 if (rhashtable_lookup_fast(ht: &bind_hash_table, key, params: ht_parms))
120 continue;
121
122 memcpy(rs->rs_bound_key, key, sizeof(rs->rs_bound_key));
123 rs->rs_bound_addr = *addr;
124 net_get_random_once(&rs->rs_hash_initval,
125 sizeof(rs->rs_hash_initval));
126 rs->rs_bound_port = cpu_to_be16(rover);
127 rs->rs_bound_node.next = NULL;
128 rds_sock_addref(rs);
129 if (!rhashtable_insert_fast(ht: &bind_hash_table,
130 obj: &rs->rs_bound_node, params: ht_parms)) {
131 *port = rs->rs_bound_port;
132 rs->rs_bound_scope_id = scope_id;
133 ret = 0;
134 rdsdebug("rs %p binding to %pI6c:%d\n",
135 rs, addr, (int)ntohs(*port));
136 break;
137 } else {
138 rs->rs_bound_addr = in6addr_any;
139 rds_sock_put(rs);
140 ret = -ENOMEM;
141 break;
142 }
143 } while (rover++ != last);
144
145 return ret;
146}
147
148void rds_remove_bound(struct rds_sock *rs)
149{
150
151 if (ipv6_addr_any(a: &rs->rs_bound_addr))
152 return;
153
154 rdsdebug("rs %p unbinding from %pI6c:%d\n",
155 rs, &rs->rs_bound_addr,
156 ntohs(rs->rs_bound_port));
157
158 rhashtable_remove_fast(ht: &bind_hash_table, obj: &rs->rs_bound_node, params: ht_parms);
159 rds_sock_put(rs);
160 rs->rs_bound_addr = in6addr_any;
161}
162
163int rds_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
164{
165 struct sock *sk = sock->sk;
166 struct rds_sock *rs = rds_sk_to_rs(sk);
167 struct in6_addr v6addr, *binding_addr;
168 struct rds_transport *trans;
169 __u32 scope_id = 0;
170 int ret = 0;
171 __be16 port;
172
173 /* We allow an RDS socket to be bound to either IPv4 or IPv6
174 * address.
175 */
176 if (addr_len < offsetofend(struct sockaddr, sa_family))
177 return -EINVAL;
178 if (uaddr->sa_family == AF_INET) {
179 struct sockaddr_in *sin = (struct sockaddr_in *)uaddr;
180
181 if (addr_len < sizeof(struct sockaddr_in) ||
182 sin->sin_addr.s_addr == htonl(INADDR_ANY) ||
183 sin->sin_addr.s_addr == htonl(INADDR_BROADCAST) ||
184 ipv4_is_multicast(addr: sin->sin_addr.s_addr))
185 return -EINVAL;
186 ipv6_addr_set_v4mapped(addr: sin->sin_addr.s_addr, v4mapped: &v6addr);
187 binding_addr = &v6addr;
188 port = sin->sin_port;
189#if IS_ENABLED(CONFIG_IPV6)
190 } else if (uaddr->sa_family == AF_INET6) {
191 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)uaddr;
192 int addr_type;
193
194 if (addr_len < sizeof(struct sockaddr_in6))
195 return -EINVAL;
196 addr_type = ipv6_addr_type(addr: &sin6->sin6_addr);
197 if (!(addr_type & IPV6_ADDR_UNICAST)) {
198 __be32 addr4;
199
200 if (!(addr_type & IPV6_ADDR_MAPPED))
201 return -EINVAL;
202
203 /* It is a mapped address. Need to do some sanity
204 * checks.
205 */
206 addr4 = sin6->sin6_addr.s6_addr32[3];
207 if (addr4 == htonl(INADDR_ANY) ||
208 addr4 == htonl(INADDR_BROADCAST) ||
209 ipv4_is_multicast(addr: addr4))
210 return -EINVAL;
211 }
212 /* The scope ID must be specified for link local address. */
213 if (addr_type & IPV6_ADDR_LINKLOCAL) {
214 if (sin6->sin6_scope_id == 0)
215 return -EINVAL;
216 scope_id = sin6->sin6_scope_id;
217 }
218 binding_addr = &sin6->sin6_addr;
219 port = sin6->sin6_port;
220#endif
221 } else {
222 return -EINVAL;
223 }
224 lock_sock(sk);
225
226 /* RDS socket does not allow re-binding. */
227 if (!ipv6_addr_any(a: &rs->rs_bound_addr)) {
228 ret = -EINVAL;
229 goto out;
230 }
231 /* Socket is connected. The binding address should have the same
232 * scope ID as the connected address, except the case when one is
233 * non-link local address (scope_id is 0).
234 */
235 if (!ipv6_addr_any(a: &rs->rs_conn_addr) && scope_id &&
236 rs->rs_bound_scope_id &&
237 scope_id != rs->rs_bound_scope_id) {
238 ret = -EINVAL;
239 goto out;
240 }
241
242 /* The transport can be set using SO_RDS_TRANSPORT option before the
243 * socket is bound.
244 */
245 if (rs->rs_transport) {
246 trans = rs->rs_transport;
247 if (!trans->laddr_check ||
248 trans->laddr_check(sock_net(sk: sock->sk),
249 binding_addr, scope_id) != 0) {
250 ret = -ENOPROTOOPT;
251 goto out;
252 }
253 } else {
254 trans = rds_trans_get_preferred(net: sock_net(sk: sock->sk),
255 addr: binding_addr, scope_id);
256 if (!trans) {
257 ret = -EADDRNOTAVAIL;
258 pr_info_ratelimited("RDS: %s could not find a transport for %pI6c, load rds_tcp or rds_rdma?\n",
259 __func__, binding_addr);
260 goto out;
261 }
262 rs->rs_transport = trans;
263 }
264
265 sock_set_flag(sk, flag: SOCK_RCU_FREE);
266 ret = rds_add_bound(rs, addr: binding_addr, port: &port, scope_id);
267 if (ret)
268 rs->rs_transport = NULL;
269
270out:
271 release_sock(sk);
272 return ret;
273}
274
275void rds_bind_lock_destroy(void)
276{
277 rhashtable_destroy(ht: &bind_hash_table);
278}
279
280int rds_bind_lock_init(void)
281{
282 return rhashtable_init(ht: &bind_hash_table, params: &ht_parms);
283}
284

source code of linux/net/rds/bind.c