1 /* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements. See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License. You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include "apr_strings.h"
21 #include "ap_config.h"
23 #include "http_connection.h"
24 #include "http_request.h"
25 #include "http_protocol.h"
27 #include "mpm_default.h"
28 #include "http_config.h"
29 #include "http_core.h"
30 #include "http_vhost.h"
31 #include "scoreboard.h"
33 #include "util_filter.h"
36 APR_HOOK_LINK(create_connection)
37 APR_HOOK_LINK(process_connection)
38 APR_HOOK_LINK(pre_connection)
40 AP_IMPLEMENT_HOOK_RUN_FIRST(conn_rec *,create_connection,
41 (apr_pool_t *p, server_rec *server, apr_socket_t *csd, long conn_id, void *sbh, apr_bucket_alloc_t *alloc),
42 (p, server, csd, conn_id, sbh, alloc), NULL)
43 AP_IMPLEMENT_HOOK_RUN_FIRST(int,process_connection,(conn_rec *c),(c),DECLINED)
44 AP_IMPLEMENT_HOOK_RUN_ALL(int,pre_connection,(conn_rec *c, void *csd),(c, csd),OK,DECLINED)
46 * More machine-dependent networking gooo... on some systems,
47 * you've got to be *really* sure that all the packets are acknowledged
48 * before closing the connection, since the client will not be able
49 * to see the last response if their TCP buffer is flushed by a RST
50 * packet from us, which is what the server's TCP stack will send
51 * if it receives any request data after closing the connection.
53 * In an ideal world, this function would be accomplished by simply
54 * setting the socket option SO_LINGER and handling it within the
55 * server's TCP stack while the process continues on to the next request.
56 * Unfortunately, it seems that most (if not all) operating systems
57 * block the server process on close() when SO_LINGER is used.
58 * For those that don't, see USE_SO_LINGER below. For the rest,
59 * we have created a home-brew lingering_close.
61 * Many operating systems tend to block, puke, or otherwise mishandle
62 * calls to shutdown only half of the connection. You should define
63 * NO_LINGCLOSE in ap_config.h if such is the case for your system.
65 #ifndef MAX_SECS_TO_LINGER
66 #define MAX_SECS_TO_LINGER 30
69 AP_CORE_DECLARE(void) ap_flush_conn(conn_rec *c)
71 apr_bucket_brigade *bb;
74 bb = apr_brigade_create(c->pool, c->bucket_alloc);
77 b = apr_bucket_flush_create(c->bucket_alloc);
78 APR_BRIGADE_INSERT_TAIL(bb, b);
80 /* End Of Connection bucket */
81 b = ap_bucket_eoc_create(c->bucket_alloc);
82 APR_BRIGADE_INSERT_TAIL(bb, b);
84 ap_pass_brigade(c->output_filters, bb);
87 /* we now proceed to read from the client until we get EOF, or until
88 * MAX_SECS_TO_LINGER has passed. the reasons for doing this are
89 * documented in a draft:
91 * http://www.ics.uci.edu/pub/ietf/http/draft-ietf-http-connection-00.txt
93 * in a nutshell -- if we don't make this effort we risk causing
94 * TCP RST packets to be sent which can tear down a connection before
95 * all the response data has been sent to the client.
97 #define SECONDS_TO_LINGER 2
98 AP_DECLARE(void) ap_lingering_close(conn_rec *c)
101 apr_size_t nbytes = sizeof(dummybuf);
104 apr_int32_t total_linger_time = 0;
105 apr_socket_t *csd = ap_get_module_config(c->conn_config, &core_module);
111 ap_update_child_status(c->sbh, SERVER_CLOSING, NULL);
114 ap_flush_conn(c); /* just close it */
115 apr_socket_close(csd);
119 /* Close the connection, being careful to send out whatever is still
120 * in our buffers. If possible, try to avoid a hard close until the
121 * client has ACKed our FIN and/or has stopped sending us data.
124 /* Send any leftover data to the client, but never try to again */
128 apr_socket_close(csd);
132 /* Shut down the socket for write, which will send a FIN
135 if (apr_shutdown(csd, APR_SHUTDOWN_WRITE) != APR_SUCCESS
137 apr_socket_close(csd);
141 /* Read all data from the peer until we reach "end-of-file" (FIN
142 * from peer) or we've exceeded our overall timeout. If the client does
143 * not send us bytes within 2 seconds (a value pulled from Apache 1.3
144 * which seems to work well), close the connection.
146 timeout = apr_time_from_sec(SECONDS_TO_LINGER);
147 apr_socket_timeout_set(csd, timeout);
148 apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 1);
150 nbytes = sizeof(dummybuf);
151 rc = apr_recv(csd, dummybuf, &nbytes);
152 if (rc != APR_SUCCESS || nbytes == 0)
155 total_linger_time += SECONDS_TO_LINGER;
156 if (total_linger_time >= MAX_SECS_TO_LINGER) {
161 apr_socket_close(csd);
165 AP_CORE_DECLARE(void) ap_process_connection(conn_rec *c, void *csd)
168 ap_update_vhost_given_ip(c);
170 rc = ap_run_pre_connection(c, csd);
171 if (rc != OK && rc != DONE) {
176 ap_run_process_connection(c);