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1/*
2 * Copyright (c) 2006 Oracle. 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 <linux/gfp.h>
35#include <linux/in.h>
36#include <net/tcp.h>
37
38#include "rds.h"
39#include "tcp.h"
40
41int rds_tcp_keepalive(struct socket *sock)
42{
43 /* values below based on xs_udp_default_timeout */
44 int keepidle = 5; /* send a probe 'keepidle' secs after last data */
45 int keepcnt = 5; /* number of unack'ed probes before declaring dead */
46 int keepalive = 1;
47 int ret = 0;
48
49 ret = kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
50 (char *)&keepalive, sizeof(keepalive));
51 if (ret < 0)
52 goto bail;
53
54 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPCNT,
55 (char *)&keepcnt, sizeof(keepcnt));
56 if (ret < 0)
57 goto bail;
58
59 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPIDLE,
60 (char *)&keepidle, sizeof(keepidle));
61 if (ret < 0)
62 goto bail;
63
64 /* KEEPINTVL is the interval between successive probes. We follow
65 * the model in xs_tcp_finish_connecting() and re-use keepidle.
66 */
67 ret = kernel_setsockopt(sock, IPPROTO_TCP, TCP_KEEPINTVL,
68 (char *)&keepidle, sizeof(keepidle));
69bail:
70 return ret;
71}
72
73int rds_tcp_accept_one(struct socket *sock)
74{
75 struct socket *new_sock = NULL;
76 struct rds_connection *conn;
77 int ret;
78 struct inet_sock *inet;
79 struct rds_tcp_connection *rs_tcp = NULL;
80 int conn_state;
81 struct sock *nsk;
82
83 ret = sock_create_kern(sock_net(sock->sk), sock->sk->sk_family,
84 sock->sk->sk_type, sock->sk->sk_protocol,
85 &new_sock);
86 if (ret)
87 goto out;
88
89 new_sock->type = sock->type;
90 new_sock->ops = sock->ops;
91 ret = sock->ops->accept(sock, new_sock, O_NONBLOCK);
92 if (ret < 0)
93 goto out;
94
95 ret = rds_tcp_keepalive(new_sock);
96 if (ret < 0)
97 goto out;
98
99 rds_tcp_tune(new_sock);
100
101 inet = inet_sk(new_sock->sk);
102
103 rdsdebug("accepted tcp %pI4:%u -> %pI4:%u\n",
104 &inet->inet_saddr, ntohs(inet->inet_sport),
105 &inet->inet_daddr, ntohs(inet->inet_dport));
106
107 conn = rds_conn_create(sock_net(sock->sk),
108 inet->inet_saddr, inet->inet_daddr,
109 &rds_tcp_transport, GFP_KERNEL);
110 if (IS_ERR(conn)) {
111 ret = PTR_ERR(conn);
112 goto out;
113 }
114 /* An incoming SYN request came in, and TCP just accepted it.
115 *
116 * If the client reboots, this conn will need to be cleaned up.
117 * rds_tcp_state_change() will do that cleanup
118 */
119 rs_tcp = (struct rds_tcp_connection *)conn->c_transport_data;
120 rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING);
121 mutex_lock(&rs_tcp->t_conn_lock);
122 conn_state = rds_conn_state(conn);
123 if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_UP)
124 goto rst_nsk;
125 if (rs_tcp->t_sock) {
126 /* Need to resolve a duelling SYN between peers.
127 * We have an outstanding SYN to this peer, which may
128 * potentially have transitioned to the RDS_CONN_UP state,
129 * so we must quiesce any send threads before resetting
130 * c_transport_data.
131 */
132 wait_event(conn->c_waitq,
133 !test_bit(RDS_IN_XMIT, &conn->c_flags));
134 if (ntohl(inet->inet_saddr) < ntohl(inet->inet_daddr)) {
135 goto rst_nsk;
136 } else if (rs_tcp->t_sock) {
137 rds_tcp_restore_callbacks(rs_tcp->t_sock, rs_tcp);
138 conn->c_outgoing = 0;
139 }
140 }
141 rds_tcp_set_callbacks(new_sock, conn);
142 rds_connect_complete(conn); /* marks RDS_CONN_UP */
143 new_sock = NULL;
144 ret = 0;
145 goto out;
146rst_nsk:
147 /* reset the newly returned accept sock and bail */
148 nsk = new_sock->sk;
149 rds_tcp_stats_inc(s_tcp_listen_closed_stale);
150 nsk->sk_user_data = NULL;
151 nsk->sk_prot->disconnect(nsk, 0);
152 tcp_done(nsk);
153 new_sock = NULL;
154 ret = 0;
155out:
156 if (rs_tcp)
157 mutex_unlock(&rs_tcp->t_conn_lock);
158 if (new_sock)
159 sock_release(new_sock);
160 return ret;
161}
162
163void rds_tcp_listen_data_ready(struct sock *sk)
164{
165 void (*ready)(struct sock *sk);
166
167 rdsdebug("listen data ready sk %p\n", sk);
168
169 read_lock(&sk->sk_callback_lock);
170 ready = sk->sk_user_data;
171 if (!ready) { /* check for teardown race */
172 ready = sk->sk_data_ready;
173 goto out;
174 }
175
176 /*
177 * ->sk_data_ready is also called for a newly established child socket
178 * before it has been accepted and the accepter has set up their
179 * data_ready.. we only want to queue listen work for our listening
180 * socket
181 */
182 if (sk->sk_state == TCP_LISTEN)
183 rds_tcp_accept_work(sk);
184
185out:
186 read_unlock(&sk->sk_callback_lock);
187 ready(sk);
188}
189
190struct socket *rds_tcp_listen_init(struct net *net)
191{
192 struct sockaddr_in sin;
193 struct socket *sock = NULL;
194 int ret;
195
196 ret = sock_create_kern(net, PF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
197 if (ret < 0)
198 goto out;
199
200 sock->sk->sk_reuse = SK_CAN_REUSE;
201 rds_tcp_nonagle(sock);
202
203 write_lock_bh(&sock->sk->sk_callback_lock);
204 sock->sk->sk_user_data = sock->sk->sk_data_ready;
205 sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
206 write_unlock_bh(&sock->sk->sk_callback_lock);
207
208 sin.sin_family = PF_INET;
209 sin.sin_addr.s_addr = (__force u32)htonl(INADDR_ANY);
210 sin.sin_port = (__force u16)htons(RDS_TCP_PORT);
211
212 ret = sock->ops->bind(sock, (struct sockaddr *)&sin, sizeof(sin));
213 if (ret < 0)
214 goto out;
215
216 ret = sock->ops->listen(sock, 64);
217 if (ret < 0)
218 goto out;
219
220 return sock;
221out:
222 if (sock)
223 sock_release(sock);
224 return NULL;
225}
226
227void rds_tcp_listen_stop(struct socket *sock)
228{
229 struct sock *sk;
230
231 if (!sock)
232 return;
233
234 sk = sock->sk;
235
236 /* serialize with and prevent further callbacks */
237 lock_sock(sk);
238 write_lock_bh(&sk->sk_callback_lock);
239 if (sk->sk_user_data) {
240 sk->sk_data_ready = sk->sk_user_data;
241 sk->sk_user_data = NULL;
242 }
243 write_unlock_bh(&sk->sk_callback_lock);
244 release_sock(sk);
245
246 /* wait for accepts to stop and close the socket */
247 flush_workqueue(rds_wq);
248 sock_release(sock);
249}
1/*
2 * Copyright (c) 2006, 2018 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 <linux/gfp.h>
35#include <linux/in.h>
36#include <net/tcp.h>
37#include <trace/events/sock.h>
38
39#include "rds.h"
40#include "tcp.h"
41
42void rds_tcp_keepalive(struct socket *sock)
43{
44 /* values below based on xs_udp_default_timeout */
45 int keepidle = 5; /* send a probe 'keepidle' secs after last data */
46 int keepcnt = 5; /* number of unack'ed probes before declaring dead */
47
48 sock_set_keepalive(sock->sk);
49 tcp_sock_set_keepcnt(sock->sk, keepcnt);
50 tcp_sock_set_keepidle(sock->sk, keepidle);
51 /* KEEPINTVL is the interval between successive probes. We follow
52 * the model in xs_tcp_finish_connecting() and re-use keepidle.
53 */
54 tcp_sock_set_keepintvl(sock->sk, keepidle);
55}
56
57/* rds_tcp_accept_one_path(): if accepting on cp_index > 0, make sure the
58 * client's ipaddr < server's ipaddr. Otherwise, close the accepted
59 * socket and force a reconneect from smaller -> larger ip addr. The reason
60 * we special case cp_index 0 is to allow the rds probe ping itself to itself
61 * get through efficiently.
62 * Since reconnects are only initiated from the node with the numerically
63 * smaller ip address, we recycle conns in RDS_CONN_ERROR on the passive side
64 * by moving them to CONNECTING in this function.
65 */
66static
67struct rds_tcp_connection *rds_tcp_accept_one_path(struct rds_connection *conn)
68{
69 int i;
70 int npaths = max_t(int, 1, conn->c_npaths);
71
72 /* for mprds, all paths MUST be initiated by the peer
73 * with the smaller address.
74 */
75 if (rds_addr_cmp(&conn->c_faddr, &conn->c_laddr) >= 0) {
76 /* Make sure we initiate at least one path if this
77 * has not already been done; rds_start_mprds() will
78 * take care of additional paths, if necessary.
79 */
80 if (npaths == 1)
81 rds_conn_path_connect_if_down(&conn->c_path[0]);
82 return NULL;
83 }
84
85 for (i = 0; i < npaths; i++) {
86 struct rds_conn_path *cp = &conn->c_path[i];
87
88 if (rds_conn_path_transition(cp, RDS_CONN_DOWN,
89 RDS_CONN_CONNECTING) ||
90 rds_conn_path_transition(cp, RDS_CONN_ERROR,
91 RDS_CONN_CONNECTING)) {
92 return cp->cp_transport_data;
93 }
94 }
95 return NULL;
96}
97
98int rds_tcp_accept_one(struct socket *sock)
99{
100 struct socket *new_sock = NULL;
101 struct rds_connection *conn;
102 int ret;
103 struct inet_sock *inet;
104 struct rds_tcp_connection *rs_tcp = NULL;
105 int conn_state;
106 struct rds_conn_path *cp;
107 struct in6_addr *my_addr, *peer_addr;
108 struct proto_accept_arg arg = {
109 .flags = O_NONBLOCK,
110 .kern = true,
111 };
112#if !IS_ENABLED(CONFIG_IPV6)
113 struct in6_addr saddr, daddr;
114#endif
115 int dev_if = 0;
116
117 if (!sock) /* module unload or netns delete in progress */
118 return -ENETUNREACH;
119
120 ret = sock_create_lite(sock->sk->sk_family,
121 sock->sk->sk_type, sock->sk->sk_protocol,
122 &new_sock);
123 if (ret)
124 goto out;
125
126 ret = sock->ops->accept(sock, new_sock, &arg);
127 if (ret < 0)
128 goto out;
129
130 /* sock_create_lite() does not get a hold on the owner module so we
131 * need to do it here. Note that sock_release() uses sock->ops to
132 * determine if it needs to decrement the reference count. So set
133 * sock->ops after calling accept() in case that fails. And there's
134 * no need to do try_module_get() as the listener should have a hold
135 * already.
136 */
137 new_sock->ops = sock->ops;
138 __module_get(new_sock->ops->owner);
139
140 rds_tcp_keepalive(new_sock);
141 if (!rds_tcp_tune(new_sock)) {
142 ret = -EINVAL;
143 goto out;
144 }
145
146 inet = inet_sk(new_sock->sk);
147
148#if IS_ENABLED(CONFIG_IPV6)
149 my_addr = &new_sock->sk->sk_v6_rcv_saddr;
150 peer_addr = &new_sock->sk->sk_v6_daddr;
151#else
152 ipv6_addr_set_v4mapped(inet->inet_saddr, &saddr);
153 ipv6_addr_set_v4mapped(inet->inet_daddr, &daddr);
154 my_addr = &saddr;
155 peer_addr = &daddr;
156#endif
157 rdsdebug("accepted family %d tcp %pI6c:%u -> %pI6c:%u\n",
158 sock->sk->sk_family,
159 my_addr, ntohs(inet->inet_sport),
160 peer_addr, ntohs(inet->inet_dport));
161
162#if IS_ENABLED(CONFIG_IPV6)
163 /* sk_bound_dev_if is not set if the peer address is not link local
164 * address. In this case, it happens that mcast_oif is set. So
165 * just use it.
166 */
167 if ((ipv6_addr_type(my_addr) & IPV6_ADDR_LINKLOCAL) &&
168 !(ipv6_addr_type(peer_addr) & IPV6_ADDR_LINKLOCAL)) {
169 struct ipv6_pinfo *inet6;
170
171 inet6 = inet6_sk(new_sock->sk);
172 dev_if = READ_ONCE(inet6->mcast_oif);
173 } else {
174 dev_if = new_sock->sk->sk_bound_dev_if;
175 }
176#endif
177
178 if (!rds_tcp_laddr_check(sock_net(sock->sk), peer_addr, dev_if)) {
179 /* local address connection is only allowed via loopback */
180 ret = -EOPNOTSUPP;
181 goto out;
182 }
183
184 conn = rds_conn_create(sock_net(sock->sk),
185 my_addr, peer_addr,
186 &rds_tcp_transport, 0, GFP_KERNEL, dev_if);
187
188 if (IS_ERR(conn)) {
189 ret = PTR_ERR(conn);
190 goto out;
191 }
192 /* An incoming SYN request came in, and TCP just accepted it.
193 *
194 * If the client reboots, this conn will need to be cleaned up.
195 * rds_tcp_state_change() will do that cleanup
196 */
197 rs_tcp = rds_tcp_accept_one_path(conn);
198 if (!rs_tcp)
199 goto rst_nsk;
200 mutex_lock(&rs_tcp->t_conn_path_lock);
201 cp = rs_tcp->t_cpath;
202 conn_state = rds_conn_path_state(cp);
203 WARN_ON(conn_state == RDS_CONN_UP);
204 if (conn_state != RDS_CONN_CONNECTING && conn_state != RDS_CONN_ERROR)
205 goto rst_nsk;
206 if (rs_tcp->t_sock) {
207 /* Duelling SYN has been handled in rds_tcp_accept_one() */
208 rds_tcp_reset_callbacks(new_sock, cp);
209 /* rds_connect_path_complete() marks RDS_CONN_UP */
210 rds_connect_path_complete(cp, RDS_CONN_RESETTING);
211 } else {
212 rds_tcp_set_callbacks(new_sock, cp);
213 rds_connect_path_complete(cp, RDS_CONN_CONNECTING);
214 }
215 new_sock = NULL;
216 ret = 0;
217 if (conn->c_npaths == 0)
218 rds_send_ping(cp->cp_conn, cp->cp_index);
219 goto out;
220rst_nsk:
221 /* reset the newly returned accept sock and bail.
222 * It is safe to set linger on new_sock because the RDS connection
223 * has not been brought up on new_sock, so no RDS-level data could
224 * be pending on it. By setting linger, we achieve the side-effect
225 * of avoiding TIME_WAIT state on new_sock.
226 */
227 sock_no_linger(new_sock->sk);
228 kernel_sock_shutdown(new_sock, SHUT_RDWR);
229 ret = 0;
230out:
231 if (rs_tcp)
232 mutex_unlock(&rs_tcp->t_conn_path_lock);
233 if (new_sock)
234 sock_release(new_sock);
235 return ret;
236}
237
238void rds_tcp_listen_data_ready(struct sock *sk)
239{
240 void (*ready)(struct sock *sk);
241
242 trace_sk_data_ready(sk);
243 rdsdebug("listen data ready sk %p\n", sk);
244
245 read_lock_bh(&sk->sk_callback_lock);
246 ready = sk->sk_user_data;
247 if (!ready) { /* check for teardown race */
248 ready = sk->sk_data_ready;
249 goto out;
250 }
251
252 /*
253 * ->sk_data_ready is also called for a newly established child socket
254 * before it has been accepted and the accepter has set up their
255 * data_ready.. we only want to queue listen work for our listening
256 * socket
257 *
258 * (*ready)() may be null if we are racing with netns delete, and
259 * the listen socket is being torn down.
260 */
261 if (sk->sk_state == TCP_LISTEN)
262 rds_tcp_accept_work(sk);
263 else
264 ready = rds_tcp_listen_sock_def_readable(sock_net(sk));
265
266out:
267 read_unlock_bh(&sk->sk_callback_lock);
268 if (ready)
269 ready(sk);
270}
271
272struct socket *rds_tcp_listen_init(struct net *net, bool isv6)
273{
274 struct socket *sock = NULL;
275 struct sockaddr_storage ss;
276 struct sockaddr_in6 *sin6;
277 struct sockaddr_in *sin;
278 int addr_len;
279 int ret;
280
281 ret = sock_create_kern(net, isv6 ? PF_INET6 : PF_INET, SOCK_STREAM,
282 IPPROTO_TCP, &sock);
283 if (ret < 0) {
284 rdsdebug("could not create %s listener socket: %d\n",
285 isv6 ? "IPv6" : "IPv4", ret);
286 goto out;
287 }
288
289 sock->sk->sk_reuse = SK_CAN_REUSE;
290 tcp_sock_set_nodelay(sock->sk);
291
292 write_lock_bh(&sock->sk->sk_callback_lock);
293 sock->sk->sk_user_data = sock->sk->sk_data_ready;
294 sock->sk->sk_data_ready = rds_tcp_listen_data_ready;
295 write_unlock_bh(&sock->sk->sk_callback_lock);
296
297 if (isv6) {
298 sin6 = (struct sockaddr_in6 *)&ss;
299 sin6->sin6_family = PF_INET6;
300 sin6->sin6_addr = in6addr_any;
301 sin6->sin6_port = (__force u16)htons(RDS_TCP_PORT);
302 sin6->sin6_scope_id = 0;
303 sin6->sin6_flowinfo = 0;
304 addr_len = sizeof(*sin6);
305 } else {
306 sin = (struct sockaddr_in *)&ss;
307 sin->sin_family = PF_INET;
308 sin->sin_addr.s_addr = INADDR_ANY;
309 sin->sin_port = (__force u16)htons(RDS_TCP_PORT);
310 addr_len = sizeof(*sin);
311 }
312
313 ret = kernel_bind(sock, (struct sockaddr *)&ss, addr_len);
314 if (ret < 0) {
315 rdsdebug("could not bind %s listener socket: %d\n",
316 isv6 ? "IPv6" : "IPv4", ret);
317 goto out;
318 }
319
320 ret = sock->ops->listen(sock, 64);
321 if (ret < 0)
322 goto out;
323
324 return sock;
325out:
326 if (sock)
327 sock_release(sock);
328 return NULL;
329}
330
331void rds_tcp_listen_stop(struct socket *sock, struct work_struct *acceptor)
332{
333 struct sock *sk;
334
335 if (!sock)
336 return;
337
338 sk = sock->sk;
339
340 /* serialize with and prevent further callbacks */
341 lock_sock(sk);
342 write_lock_bh(&sk->sk_callback_lock);
343 if (sk->sk_user_data) {
344 sk->sk_data_ready = sk->sk_user_data;
345 sk->sk_user_data = NULL;
346 }
347 write_unlock_bh(&sk->sk_callback_lock);
348 release_sock(sk);
349
350 /* wait for accepts to stop and close the socket */
351 flush_workqueue(rds_wq);
352 flush_work(acceptor);
353 sock_release(sock);
354}