1 /* incoming call handling
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/module.h>
15 #include <linux/net.h>
16 #include <linux/skbuff.h>
17 #include <linux/errqueue.h>
18 #include <linux/udp.h>
20 #include <linux/in6.h>
21 #include <linux/icmp.h>
22 #include <linux/gfp.h>
24 #include <net/af_rxrpc.h>
26 #include "ar-internal.h"
29 * generate a connection-level abort
31 static int rxrpc_busy(struct rxrpc_local *local, struct sockaddr_rxrpc *srx,
32 struct rxrpc_wire_header *whdr)
39 _enter("%d,,", local->debug_id);
41 whdr->type = RXRPC_PACKET_TYPE_BUSY;
42 whdr->serial = htonl(1);
44 msg.msg_name = &srx->transport.sin;
45 msg.msg_namelen = sizeof(srx->transport.sin);
46 msg.msg_control = NULL;
47 msg.msg_controllen = 0;
50 iov[0].iov_base = whdr;
51 iov[0].iov_len = sizeof(*whdr);
55 _proto("Tx BUSY %%1");
57 ret = kernel_sendmsg(local->socket, &msg, iov, 1, len);
59 _leave(" = -EAGAIN [sendmsg failed: %d]", ret);
68 * accept an incoming call that needs peer, transport and/or connection setting
71 static int rxrpc_accept_incoming_call(struct rxrpc_local *local,
72 struct rxrpc_sock *rx,
74 struct sockaddr_rxrpc *srx)
76 struct rxrpc_connection *conn;
77 struct rxrpc_skb_priv *sp, *nsp;
78 struct rxrpc_call *call;
79 struct sk_buff *notification;
86 /* get a notification message to send to the server app */
87 notification = alloc_skb(0, GFP_NOFS);
93 rxrpc_new_skb(notification);
94 notification->mark = RXRPC_SKB_MARK_NEW_CALL;
96 conn = rxrpc_incoming_connection(local, srx, skb);
103 call = rxrpc_incoming_call(rx, conn, skb);
104 rxrpc_put_connection(conn);
111 /* attach the call to the socket */
112 read_lock_bh(&local->services_lock);
113 if (rx->sk.sk_state == RXRPC_CLOSE)
114 goto invalid_service;
116 write_lock(&rx->call_lock);
117 if (!test_and_set_bit(RXRPC_CALL_INIT_ACCEPT, &call->flags)) {
118 rxrpc_get_call(call);
120 spin_lock(&call->conn->state_lock);
121 if (sp->hdr.securityIndex > 0 &&
122 call->conn->state == RXRPC_CONN_SERVICE_UNSECURED) {
123 _debug("await conn sec");
124 list_add_tail(&call->accept_link, &rx->secureq);
125 call->conn->state = RXRPC_CONN_SERVICE_CHALLENGING;
126 set_bit(RXRPC_CONN_EV_CHALLENGE, &call->conn->events);
127 rxrpc_queue_conn(call->conn);
129 _debug("conn ready");
130 call->state = RXRPC_CALL_SERVER_ACCEPTING;
131 list_add_tail(&call->accept_link, &rx->acceptq);
132 rxrpc_get_call(call);
133 atomic_inc(&call->skb_count);
134 nsp = rxrpc_skb(notification);
137 ASSERTCMP(atomic_read(&call->usage), >=, 3);
140 spin_lock(&call->lock);
141 ret = rxrpc_queue_rcv_skb(call, notification, true,
143 spin_unlock(&call->lock);
147 spin_unlock(&call->conn->state_lock);
151 write_unlock(&rx->call_lock);
154 rxrpc_fast_process_packet(call, skb);
157 read_unlock_bh(&local->services_lock);
158 rxrpc_free_skb(notification);
159 rxrpc_put_call(call);
165 read_unlock_bh(&local->services_lock);
167 read_lock_bh(&call->state_lock);
168 if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
169 !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events)) {
170 rxrpc_get_call(call);
171 rxrpc_queue_call(call);
173 read_unlock_bh(&call->state_lock);
174 rxrpc_put_call(call);
177 rxrpc_free_skb(notification);
179 _leave(" = %d", ret);
184 * accept incoming calls that need peer, transport and/or connection setting up
185 * - the packets we get are all incoming client DATA packets that have seq == 1
187 void rxrpc_accept_incoming_calls(struct rxrpc_local *local)
189 struct rxrpc_skb_priv *sp;
190 struct sockaddr_rxrpc srx;
191 struct rxrpc_sock *rx;
192 struct rxrpc_wire_header whdr;
196 _enter("%d", local->debug_id);
198 skb = skb_dequeue(&local->accept_queue);
204 _net("incoming call skb %p", skb);
208 /* Set up a response packet header in case we need it */
209 whdr.epoch = htonl(sp->hdr.epoch);
210 whdr.cid = htonl(sp->hdr.cid);
211 whdr.callNumber = htonl(sp->hdr.callNumber);
212 whdr.seq = htonl(sp->hdr.seq);
217 whdr.securityIndex = sp->hdr.securityIndex;
219 whdr.serviceId = htons(sp->hdr.serviceId);
221 if (rxrpc_extract_addr_from_skb(&srx, skb) < 0)
224 /* get the socket providing the service */
225 read_lock_bh(&local->services_lock);
226 list_for_each_entry(rx, &local->services, listen_link) {
227 if (rx->srx.srx_service == sp->hdr.serviceId &&
228 rx->sk.sk_state != RXRPC_CLOSE)
231 read_unlock_bh(&local->services_lock);
232 goto invalid_service;
235 _debug("found service %hd", rx->srx.srx_service);
236 if (sk_acceptq_is_full(&rx->sk))
238 sk_acceptq_added(&rx->sk);
240 read_unlock_bh(&local->services_lock);
242 ret = rxrpc_accept_incoming_call(local, rx, skb, &srx);
244 sk_acceptq_removed(&rx->sk);
247 case -ECONNRESET: /* old calls are ignored */
248 case -ECONNABORTED: /* aborted calls are reaborted or ignored */
252 goto invalid_service;
256 goto security_mismatch;
262 read_unlock_bh(&local->services_lock);
264 rxrpc_busy(local, &srx, &whdr);
273 skb->priority = RX_INVALID_OPERATION;
274 rxrpc_reject_packet(local, skb);
277 /* can't change connection security type mid-flow */
279 skb->priority = RX_PROTOCOL_ERROR;
280 rxrpc_reject_packet(local, skb);
285 * handle acceptance of a call by userspace
286 * - assign the user call ID to the call at the front of the queue
288 struct rxrpc_call *rxrpc_accept_call(struct rxrpc_sock *rx,
289 unsigned long user_call_ID)
291 struct rxrpc_call *call;
292 struct rb_node *parent, **pp;
295 _enter(",%lx", user_call_ID);
297 ASSERT(!irqs_disabled());
299 write_lock(&rx->call_lock);
302 if (list_empty(&rx->acceptq))
305 /* check the user ID isn't already in use */
307 pp = &rx->calls.rb_node;
311 call = rb_entry(parent, struct rxrpc_call, sock_node);
313 if (user_call_ID < call->user_call_ID)
314 pp = &(*pp)->rb_left;
315 else if (user_call_ID > call->user_call_ID)
316 pp = &(*pp)->rb_right;
321 /* dequeue the first call and check it's still valid */
322 call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
323 list_del_init(&call->accept_link);
324 sk_acceptq_removed(&rx->sk);
326 write_lock_bh(&call->state_lock);
327 switch (call->state) {
328 case RXRPC_CALL_SERVER_ACCEPTING:
329 call->state = RXRPC_CALL_SERVER_RECV_REQUEST;
331 case RXRPC_CALL_REMOTELY_ABORTED:
332 case RXRPC_CALL_LOCALLY_ABORTED:
335 case RXRPC_CALL_NETWORK_ERROR:
336 ret = call->conn->error;
338 case RXRPC_CALL_DEAD:
345 /* formalise the acceptance */
346 call->user_call_ID = user_call_ID;
347 rb_link_node(&call->sock_node, parent, pp);
348 rb_insert_color(&call->sock_node, &rx->calls);
349 if (test_and_set_bit(RXRPC_CALL_HAS_USERID, &call->flags))
351 if (test_and_set_bit(RXRPC_CALL_EV_ACCEPTED, &call->events))
353 rxrpc_queue_call(call);
355 rxrpc_get_call(call);
356 write_unlock_bh(&call->state_lock);
357 write_unlock(&rx->call_lock);
358 _leave(" = %p{%d}", call, call->debug_id);
361 /* if the call is already dying or dead, then we leave the socket's ref
362 * on it to be released by rxrpc_dead_call_expired() as induced by
363 * rxrpc_release_call() */
365 _debug("release %p", call);
366 if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
367 !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
368 rxrpc_queue_call(call);
370 write_unlock_bh(&call->state_lock);
371 _debug("discard %p", call);
373 write_unlock(&rx->call_lock);
374 _leave(" = %d", ret);
379 * Handle rejection of a call by userspace
380 * - reject the call at the front of the queue
382 int rxrpc_reject_call(struct rxrpc_sock *rx)
384 struct rxrpc_call *call;
389 ASSERT(!irqs_disabled());
391 write_lock(&rx->call_lock);
394 if (list_empty(&rx->acceptq))
397 /* dequeue the first call and check it's still valid */
398 call = list_entry(rx->acceptq.next, struct rxrpc_call, accept_link);
399 list_del_init(&call->accept_link);
400 sk_acceptq_removed(&rx->sk);
402 write_lock_bh(&call->state_lock);
403 switch (call->state) {
404 case RXRPC_CALL_SERVER_ACCEPTING:
405 call->state = RXRPC_CALL_SERVER_BUSY;
406 if (test_and_set_bit(RXRPC_CALL_EV_REJECT_BUSY, &call->events))
407 rxrpc_queue_call(call);
410 case RXRPC_CALL_REMOTELY_ABORTED:
411 case RXRPC_CALL_LOCALLY_ABORTED:
414 case RXRPC_CALL_NETWORK_ERROR:
415 ret = call->conn->error;
417 case RXRPC_CALL_DEAD:
424 /* if the call is already dying or dead, then we leave the socket's ref
425 * on it to be released by rxrpc_dead_call_expired() as induced by
426 * rxrpc_release_call() */
428 _debug("release %p", call);
429 if (!test_bit(RXRPC_CALL_RELEASED, &call->flags) &&
430 !test_and_set_bit(RXRPC_CALL_EV_RELEASE, &call->events))
431 rxrpc_queue_call(call);
433 write_unlock_bh(&call->state_lock);
434 _debug("discard %p", call);
436 write_unlock(&rx->call_lock);
437 _leave(" = %d", ret);
442 * rxrpc_kernel_accept_call - Allow a kernel service to accept an incoming call
443 * @sock: The socket on which the impending call is waiting
444 * @user_call_ID: The tag to attach to the call
446 * Allow a kernel service to accept an incoming call, assuming the incoming
447 * call is still valid.
449 struct rxrpc_call *rxrpc_kernel_accept_call(struct socket *sock,
450 unsigned long user_call_ID)
452 struct rxrpc_call *call;
454 _enter(",%lx", user_call_ID);
455 call = rxrpc_accept_call(rxrpc_sk(sock->sk), user_call_ID);
456 _leave(" = %p", call);
459 EXPORT_SYMBOL(rxrpc_kernel_accept_call);
462 * rxrpc_kernel_reject_call - Allow a kernel service to reject an incoming call
463 * @sock: The socket on which the impending call is waiting
465 * Allow a kernel service to reject an incoming call with a BUSY message,
466 * assuming the incoming call is still valid.
468 int rxrpc_kernel_reject_call(struct socket *sock)
473 ret = rxrpc_reject_call(rxrpc_sk(sock->sk));
474 _leave(" = %d", ret);
477 EXPORT_SYMBOL(rxrpc_kernel_reject_call);