granicus.if.org Git - apache/blob - modules/http/http_core.c

   1 /* Copyright 1999-2006 The Apache Software Foundation or its licensors, as
   2  * applicable.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  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.
  15  */
  16
  17 #include "apr_strings.h"
  18 #include "apr_thread_proc.h"    /* for RLIMIT stuff */
  19
  20 #define APR_WANT_STRFUNC
  21 #include "apr_want.h"
  22
  23 #define CORE_PRIVATE
  24 #include "httpd.h"
  25 #include "http_config.h"
  26 #include "http_connection.h"
  27 #include "http_core.h"
  28 #include "http_protocol.h"   /* For index_of_response().  Grump. */
  29 #include "http_request.h"
  30
  31 #include "util_filter.h"
  32 #include "util_ebcdic.h"
  33 #include "ap_mpm.h"
  34 #include "scoreboard.h"
  35
  36 #include "mod_core.h"
  37
  38 /* Handles for core filters */
  39 AP_DECLARE_DATA ap_filter_rec_t *ap_http_input_filter_handle;
  40 AP_DECLARE_DATA ap_filter_rec_t *ap_http_header_filter_handle;
  41 AP_DECLARE_DATA ap_filter_rec_t *ap_chunk_filter_handle;
  42 AP_DECLARE_DATA ap_filter_rec_t *ap_http_outerror_filter_handle;
  43 AP_DECLARE_DATA ap_filter_rec_t *ap_byterange_filter_handle;
  44
  45 static const char *set_keep_alive_timeout(cmd_parms *cmd, void *dummy,
  46                                           const char *arg)
  47 {
  48     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  49     if (err != NULL) {
  50         return err;
  51     }
  52
  53     cmd->server->keep_alive_timeout = apr_time_from_sec(atoi(arg));
  54     return NULL;
  55 }
  56
  57 static const char *set_keep_alive(cmd_parms *cmd, void *dummy,
  58                                   const char *arg)
  59 {
  60     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  61     if (err != NULL) {
  62         return err;
  63     }
  64
  65     /* We've changed it to On/Off, but used to use numbers
  66      * so we accept anything but "Off" or "0" as "On"
  67      */
  68     if (!strcasecmp(arg, "off") || !strcmp(arg, "0")) {
  69         cmd->server->keep_alive = 0;
  70     }
  71     else {
  72         cmd->server->keep_alive = 1;
  73     }
  74     return NULL;
  75 }
  76
  77 static const char *set_keep_alive_max(cmd_parms *cmd, void *dummy,
  78                                       const char *arg)
  79 {
  80     const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_LOC_FILE|NOT_IN_LIMIT);
  81     if (err != NULL) {
  82         return err;
  83     }
  84
  85     cmd->server->keep_alive_max = atoi(arg);
  86     return NULL;
  87 }
  88
  89 static const command_rec http_cmds[] = {
  90     AP_INIT_TAKE1("KeepAliveTimeout", set_keep_alive_timeout, NULL, RSRC_CONF,
  91                   "Keep-Alive timeout duration (sec)"),
  92     AP_INIT_TAKE1("MaxKeepAliveRequests", set_keep_alive_max, NULL, RSRC_CONF,
  93                   "Maximum number of Keep-Alive requests per connection, "
  94                   "or 0 for infinite"),
  95     AP_INIT_TAKE1("KeepAlive", set_keep_alive, NULL, RSRC_CONF,
  96                   "Whether persistent connections should be On or Off"),
  97     { NULL }
  98 };
  99
 100 static const char *http_scheme(const request_rec *r)
 101 {
 102     /*
 103      * The http module shouldn't return anything other than
 104      * "http" (the default) or "https".
 105      */
 106     if (r->server->server_scheme &&
 107         (strcmp(r->server->server_scheme, "https") == 0))
 108         return "https";
 109
 110     return "http";
 111 }
 112
 113 static apr_port_t http_port(const request_rec *r)
 114 {
 115     if (r->server->server_scheme &&
 116         (strcmp(r->server->server_scheme, "https") == 0))
 117         return DEFAULT_HTTPS_PORT;
 118
 119     return DEFAULT_HTTP_PORT;
 120 }
 121
 122 static int ap_process_http_async_connection(conn_rec *c)
 123 {
 124     request_rec *r;
 125     conn_state_t *cs = c->cs;
 126
 127     AP_DEBUG_ASSERT(cs->state == CONN_STATE_READ_REQUEST_LINE);
 128
 129     while (cs->state == CONN_STATE_READ_REQUEST_LINE) {
 130         ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 131
 132         if ((r = ap_read_request(c))) {
 133
 134             c->keepalive = AP_CONN_UNKNOWN;
 135             /* process the request if it was read without error */
 136
 137             ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 138             if (r->status == HTTP_OK) {
 139                 cs->state = CONN_STATE_HANDLER;
 140                 ap_process_async_request(r);
 141                 /* After the call to ap_process_request, the
 142                  * request pool may have been deleted.  We set
 143                  * r=NULL here to ensure that any dereference
 144                  * of r that might be added later in this function
 145                  * will result in a segfault immediately instead
 146                  * of nondeterministic failures later.
 147                  */
 148                 r = NULL;
 149             }
 150
 151             if (cs->state != CONN_STATE_WRITE_COMPLETION) {
 152                 /* Something went wrong; close the connection */
 153                 cs->state = CONN_STATE_LINGER;
 154             }
 155         }
 156         else {   /* ap_read_request failed - client may have closed */
 157             cs->state = CONN_STATE_LINGER;
 158         }
 159     }
 160
 161     return OK;
 162 }
 163
 164 static int ap_process_http_connection(conn_rec *c)
 165 {
 166     request_rec *r;
 167     conn_state_t *cs = c->cs;
 168     apr_socket_t *csd = NULL;
 169
 170     /*
 171      * Read and process each request found on our connection
 172      * until no requests are left or we decide to close.
 173      */
 174
 175     ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
 176     while ((r = ap_read_request(c)) != NULL) {
 177
 178         c->keepalive = AP_CONN_UNKNOWN;
 179         /* process the request if it was read without error */
 180
 181         ap_update_child_status(c->sbh, SERVER_BUSY_WRITE, r);
 182         if (r->status == HTTP_OK) {
 183             cs->state = CONN_STATE_HANDLER;
 184             ap_process_request(r);
 185             /* After the call to ap_process_request, the
 186              * request pool will have been deleted.  We set
 187              * r=NULL here to ensure that any dereference
 188              * of r that might be added later in this function
 189              * will result in a segfault immediately instead
 190              * of nondeterministic failures later.
 191              */
 192             r = NULL;
 193         }
 194
 195         if (c->keepalive != AP_CONN_KEEPALIVE || c->aborted)
 196             break;
 197
 198         ap_update_child_status(c->sbh, SERVER_BUSY_KEEPALIVE, NULL);
 199
 200         if (ap_graceful_stop_signalled())
 201             break;
 202
 203         if (!csd) {
 204             csd = ap_get_module_config(c->conn_config, &core_module);
 205         }
 206         apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 1);
 207         apr_socket_timeout_set(csd, c->base_server->keep_alive_timeout);
 208         /* Go straight to select() to wait for the next request */
 209     }
 210
 211     return OK;
 212 }
 213
 214 static int http_create_request(request_rec *r)
 215 {
 216     if (!r->main && !r->prev) {
 217         ap_add_output_filter_handle(ap_byterange_filter_handle,
 218                                     NULL, r, r->connection);
 219         ap_add_output_filter_handle(ap_content_length_filter_handle,
 220                                     NULL, r, r->connection);
 221         ap_add_output_filter_handle(ap_http_header_filter_handle,
 222                                     NULL, r, r->connection);
 223         ap_add_output_filter_handle(ap_http_outerror_filter_handle,
 224                                     NULL, r, r->connection);
 225     }
 226
 227     return OK;
 228 }
 229
 230 static void register_hooks(apr_pool_t *p)
 231 {
 232     /**
 233      * If we ae using an MPM That Supports Async Connections,
 234      * use a different processing function
 235      */
 236     int async_mpm = 0;
 237     if (ap_mpm_query(AP_MPMQ_IS_ASYNC, &async_mpm) == APR_SUCCESS
 238         && async_mpm == 1) {
 239         ap_hook_process_connection(ap_process_http_async_connection, NULL,
 240                                    NULL, APR_HOOK_REALLY_LAST);
 241     }
 242     else {
 243         ap_hook_process_connection(ap_process_http_connection, NULL, NULL,
 244                                    APR_HOOK_REALLY_LAST);
 245     }
 246
 247     ap_hook_map_to_storage(ap_send_http_trace,NULL,NULL,APR_HOOK_MIDDLE);
 248     ap_hook_http_scheme(http_scheme,NULL,NULL,APR_HOOK_REALLY_LAST);
 249     ap_hook_default_port(http_port,NULL,NULL,APR_HOOK_REALLY_LAST);
 250     ap_hook_create_request(http_create_request, NULL, NULL, APR_HOOK_REALLY_LAST);
 251     ap_http_input_filter_handle =
 252         ap_register_input_filter("HTTP_IN", ap_http_filter,
 253                                  NULL, AP_FTYPE_PROTOCOL);
 254     ap_http_header_filter_handle =
 255         ap_register_output_filter("HTTP_HEADER", ap_http_header_filter,
 256                                   NULL, AP_FTYPE_PROTOCOL);
 257     ap_chunk_filter_handle =
 258         ap_register_output_filter("CHUNK", ap_http_chunk_filter,
 259                                   NULL, AP_FTYPE_TRANSCODE);
 260     ap_http_outerror_filter_handle =
 261         ap_register_output_filter("HTTP_OUTERROR", ap_http_outerror_filter,
 262                                   NULL, AP_FTYPE_PROTOCOL);
 263     ap_byterange_filter_handle =
 264         ap_register_output_filter("BYTERANGE", ap_byterange_filter,
 265                                   NULL, AP_FTYPE_PROTOCOL);
 266     ap_method_registry_init(p);
 267 }
 268
 269 module AP_MODULE_DECLARE_DATA http_module = {
 270     STANDARD20_MODULE_STUFF,
 271     NULL,              /* create per-directory config structure */
 272     NULL,              /* merge per-directory config structures */
 273     NULL,              /* create per-server config structure */
 274     NULL,              /* merge per-server config structures */
 275     http_cmds,         /* command apr_table_t */
 276     register_hooks     /* register hooks */
 277 };