1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Local endpoint object management
4 * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 #include <linux/module.h>
11 #include <linux/net.h>
12 #include <linux/skbuff.h>
13 #include <linux/slab.h>
14 #include <linux/udp.h>
16 #include <linux/hashtable.h>
19 #include <net/udp_tunnel.h>
20 #include <net/af_rxrpc.h>
21 #include "ar-internal.h"
23 static void rxrpc_local_rcu(struct rcu_head *);
26 * Handle an ICMP/ICMP6 error turning up at the tunnel. Push it through the
27 * usual mechanism so that it gets parsed and presented through the UDP
28 * socket's error_report().
30 static void rxrpc_encap_err_rcv(struct sock *sk, struct sk_buff *skb, int err,
31 __be16 port, u32 info, u8 *payload)
33 if (ip_hdr(skb)->version == IPVERSION)
34 return ip_icmp_error(sk, skb, err, port, info, payload);
35 if (IS_ENABLED(CONFIG_AF_RXRPC_IPV6))
36 return ipv6_icmp_error(sk, skb, err, port, info, payload);
40 * Set or clear the Don't Fragment flag on a socket.
42 void rxrpc_local_dont_fragment(const struct rxrpc_local *local, bool set)
45 ip_sock_set_mtu_discover(local->socket->sk, IP_PMTUDISC_DO);
47 ip_sock_set_mtu_discover(local->socket->sk, IP_PMTUDISC_DONT);
51 * Compare a local to an address. Return -ve, 0 or +ve to indicate less than,
52 * same or greater than.
54 * We explicitly don't compare the RxRPC service ID as we want to reject
55 * conflicting uses by differing services. Further, we don't want to share
56 * addresses with different options (IPv6), so we don't compare those bits
59 static long rxrpc_local_cmp_key(const struct rxrpc_local *local,
60 const struct sockaddr_rxrpc *srx)
64 diff = ((local->srx.transport_type - srx->transport_type) ?:
65 (local->srx.transport_len - srx->transport_len) ?:
66 (local->srx.transport.family - srx->transport.family));
70 switch (srx->transport.family) {
72 /* If the choice of UDP port is left up to the transport, then
73 * the endpoint record doesn't match.
75 return ((u16 __force)local->srx.transport.sin.sin_port -
76 (u16 __force)srx->transport.sin.sin_port) ?:
77 memcmp(&local->srx.transport.sin.sin_addr,
78 &srx->transport.sin.sin_addr,
79 sizeof(struct in_addr));
80 #ifdef CONFIG_AF_RXRPC_IPV6
82 /* If the choice of UDP6 port is left up to the transport, then
83 * the endpoint record doesn't match.
85 return ((u16 __force)local->srx.transport.sin6.sin6_port -
86 (u16 __force)srx->transport.sin6.sin6_port) ?:
87 memcmp(&local->srx.transport.sin6.sin6_addr,
88 &srx->transport.sin6.sin6_addr,
89 sizeof(struct in6_addr));
96 static void rxrpc_client_conn_reap_timeout(struct timer_list *timer)
98 struct rxrpc_local *local =
99 container_of(timer, struct rxrpc_local, client_conn_reap_timer);
101 if (!local->kill_all_client_conns &&
102 test_and_set_bit(RXRPC_CLIENT_CONN_REAP_TIMER, &local->client_conn_flags))
103 rxrpc_wake_up_io_thread(local);
107 * Allocate a new local endpoint.
109 static struct rxrpc_local *rxrpc_alloc_local(struct net *net,
110 const struct sockaddr_rxrpc *srx)
112 struct rxrpc_local *local;
115 local = kzalloc(sizeof(struct rxrpc_local), GFP_KERNEL);
117 refcount_set(&local->ref, 1);
118 atomic_set(&local->active_users, 1);
120 local->rxnet = rxrpc_net(net);
121 INIT_HLIST_NODE(&local->link);
122 init_completion(&local->io_thread_ready);
123 #ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
124 skb_queue_head_init(&local->rx_delay_queue);
126 skb_queue_head_init(&local->rx_queue);
127 INIT_LIST_HEAD(&local->conn_attend_q);
128 INIT_LIST_HEAD(&local->call_attend_q);
130 local->client_bundles = RB_ROOT;
131 spin_lock_init(&local->client_bundles_lock);
132 local->kill_all_client_conns = false;
133 INIT_LIST_HEAD(&local->idle_client_conns);
134 timer_setup(&local->client_conn_reap_timer,
135 rxrpc_client_conn_reap_timeout, 0);
137 spin_lock_init(&local->lock);
138 rwlock_init(&local->services_lock);
139 local->debug_id = atomic_inc_return(&rxrpc_debug_id);
140 memcpy(&local->srx, srx, sizeof(*srx));
141 local->srx.srx_service = 0;
142 idr_init(&local->conn_ids);
143 get_random_bytes(&tmp, sizeof(tmp));
147 idr_set_cursor(&local->conn_ids, tmp);
148 INIT_LIST_HEAD(&local->new_client_calls);
149 spin_lock_init(&local->client_call_lock);
151 trace_rxrpc_local(local->debug_id, rxrpc_local_new, 1, 1);
154 _leave(" = %p", local);
159 * create the local socket
160 * - must be called with rxrpc_local_mutex locked
162 static int rxrpc_open_socket(struct rxrpc_local *local, struct net *net)
164 struct udp_tunnel_sock_cfg tuncfg = {NULL};
165 struct sockaddr_rxrpc *srx = &local->srx;
166 struct udp_port_cfg udp_conf = {0};
167 struct task_struct *io_thread;
172 local, srx->transport_type, srx->transport.family);
174 udp_conf.family = srx->transport.family;
175 udp_conf.use_udp_checksums = true;
176 if (udp_conf.family == AF_INET) {
177 udp_conf.local_ip = srx->transport.sin.sin_addr;
178 udp_conf.local_udp_port = srx->transport.sin.sin_port;
179 #if IS_ENABLED(CONFIG_AF_RXRPC_IPV6)
181 udp_conf.local_ip6 = srx->transport.sin6.sin6_addr;
182 udp_conf.local_udp_port = srx->transport.sin6.sin6_port;
183 udp_conf.use_udp6_tx_checksums = true;
184 udp_conf.use_udp6_rx_checksums = true;
187 ret = udp_sock_create(net, &udp_conf, &local->socket);
189 _leave(" = %d [socket]", ret);
193 tuncfg.encap_type = UDP_ENCAP_RXRPC;
194 tuncfg.encap_rcv = rxrpc_encap_rcv;
195 tuncfg.encap_err_rcv = rxrpc_encap_err_rcv;
196 tuncfg.sk_user_data = local;
197 setup_udp_tunnel_sock(net, local->socket, &tuncfg);
199 /* set the socket up */
200 usk = local->socket->sk;
201 usk->sk_error_report = rxrpc_error_report;
203 switch (srx->transport.family) {
205 /* we want to receive ICMPv6 errors */
206 ip6_sock_set_recverr(usk);
208 /* Fall through and set IPv4 options too otherwise we don't get
209 * errors from IPv4 packets sent through the IPv6 socket.
213 /* we want to receive ICMP errors */
214 ip_sock_set_recverr(usk);
216 /* we want to set the don't fragment bit */
217 rxrpc_local_dont_fragment(local, true);
219 /* We want receive timestamps. */
220 sock_enable_timestamps(usk);
227 io_thread = kthread_run(rxrpc_io_thread, local,
228 "krxrpcio/%u", ntohs(udp_conf.local_udp_port));
229 if (IS_ERR(io_thread)) {
230 ret = PTR_ERR(io_thread);
234 wait_for_completion(&local->io_thread_ready);
235 local->io_thread = io_thread;
240 kernel_sock_shutdown(local->socket, SHUT_RDWR);
241 local->socket->sk->sk_user_data = NULL;
242 sock_release(local->socket);
243 local->socket = NULL;
248 * Look up or create a new local endpoint using the specified local address.
250 struct rxrpc_local *rxrpc_lookup_local(struct net *net,
251 const struct sockaddr_rxrpc *srx)
253 struct rxrpc_local *local;
254 struct rxrpc_net *rxnet = rxrpc_net(net);
255 struct hlist_node *cursor;
259 _enter("{%d,%d,%pISp}",
260 srx->transport_type, srx->transport.family, &srx->transport);
262 mutex_lock(&rxnet->local_mutex);
264 hlist_for_each(cursor, &rxnet->local_endpoints) {
265 local = hlist_entry(cursor, struct rxrpc_local, link);
267 diff = rxrpc_local_cmp_key(local, srx);
271 /* Services aren't allowed to share transport sockets, so
272 * reject that here. It is possible that the object is dying -
273 * but it may also still have the local transport address that
276 if (srx->srx_service) {
281 /* Found a match. We want to replace a dying object.
282 * Attempting to bind the transport socket may still fail if
283 * we're attempting to use a local address that the dying
284 * object is still using.
286 if (!rxrpc_use_local(local, rxrpc_local_use_lookup))
292 local = rxrpc_alloc_local(net, srx);
296 ret = rxrpc_open_socket(local, net);
301 hlist_replace_rcu(cursor, &local->link);
302 cursor->pprev = NULL;
304 hlist_add_head_rcu(&local->link, &rxnet->local_endpoints);
308 mutex_unlock(&rxnet->local_mutex);
309 _leave(" = %p", local);
315 mutex_unlock(&rxnet->local_mutex);
317 call_rcu(&local->rcu, rxrpc_local_rcu);
318 _leave(" = %d", ret);
322 mutex_unlock(&rxnet->local_mutex);
323 _leave(" = -EADDRINUSE");
324 return ERR_PTR(-EADDRINUSE);
328 * Get a ref on a local endpoint.
330 struct rxrpc_local *rxrpc_get_local(struct rxrpc_local *local,
331 enum rxrpc_local_trace why)
335 u = atomic_read(&local->active_users);
336 __refcount_inc(&local->ref, &r);
337 trace_rxrpc_local(local->debug_id, why, r + 1, u);
342 * Get a ref on a local endpoint unless its usage has already reached 0.
344 struct rxrpc_local *rxrpc_get_local_maybe(struct rxrpc_local *local,
345 enum rxrpc_local_trace why)
349 if (local && __refcount_inc_not_zero(&local->ref, &r)) {
350 u = atomic_read(&local->active_users);
351 trace_rxrpc_local(local->debug_id, why, r + 1, u);
359 * Drop a ref on a local endpoint.
361 void rxrpc_put_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
363 unsigned int debug_id;
368 debug_id = local->debug_id;
370 u = atomic_read(&local->active_users);
371 dead = __refcount_dec_and_test(&local->ref, &r);
372 trace_rxrpc_local(debug_id, why, r, u);
375 call_rcu(&local->rcu, rxrpc_local_rcu);
380 * Start using a local endpoint.
382 struct rxrpc_local *rxrpc_use_local(struct rxrpc_local *local,
383 enum rxrpc_local_trace why)
385 local = rxrpc_get_local_maybe(local, rxrpc_local_get_for_use);
389 if (!__rxrpc_use_local(local, why)) {
390 rxrpc_put_local(local, rxrpc_local_put_for_use);
398 * Cease using a local endpoint. Once the number of active users reaches 0, we
399 * start the closure of the transport in the I/O thread..
401 void rxrpc_unuse_local(struct rxrpc_local *local, enum rxrpc_local_trace why)
403 unsigned int debug_id;
407 debug_id = local->debug_id;
408 r = refcount_read(&local->ref);
409 u = atomic_dec_return(&local->active_users);
410 trace_rxrpc_local(debug_id, why, r, u);
412 kthread_stop(local->io_thread);
417 * Destroy a local endpoint's socket and then hand the record to RCU to dispose
420 * Closing the socket cannot be done from bottom half context or RCU callback
421 * context because it might sleep.
423 void rxrpc_destroy_local(struct rxrpc_local *local)
425 struct socket *socket = local->socket;
426 struct rxrpc_net *rxnet = local->rxnet;
428 _enter("%d", local->debug_id);
432 mutex_lock(&rxnet->local_mutex);
433 hlist_del_init_rcu(&local->link);
434 mutex_unlock(&rxnet->local_mutex);
436 rxrpc_clean_up_local_conns(local);
437 rxrpc_service_connection_reaper(&rxnet->service_conn_reaper);
438 ASSERT(!local->service);
441 local->socket = NULL;
442 kernel_sock_shutdown(socket, SHUT_RDWR);
443 socket->sk->sk_user_data = NULL;
444 sock_release(socket);
447 /* At this point, there should be no more packets coming in to the
450 #ifdef CONFIG_AF_RXRPC_INJECT_RX_DELAY
451 rxrpc_purge_queue(&local->rx_delay_queue);
453 rxrpc_purge_queue(&local->rx_queue);
454 rxrpc_purge_client_connections(local);
458 * Destroy a local endpoint after the RCU grace period expires.
460 static void rxrpc_local_rcu(struct rcu_head *rcu)
462 struct rxrpc_local *local = container_of(rcu, struct rxrpc_local, rcu);
464 rxrpc_see_local(local, rxrpc_local_free);
469 * Verify the local endpoint list is empty by this point.
471 void rxrpc_destroy_all_locals(struct rxrpc_net *rxnet)
473 struct rxrpc_local *local;
477 flush_workqueue(rxrpc_workqueue);
479 if (!hlist_empty(&rxnet->local_endpoints)) {
480 mutex_lock(&rxnet->local_mutex);
481 hlist_for_each_entry(local, &rxnet->local_endpoints, link) {
482 pr_err("AF_RXRPC: Leaked local %p {%d}\n",
483 local, refcount_read(&local->ref));
485 mutex_unlock(&rxnet->local_mutex);