granicus.if.org Git - apache/blob - modules/proxy/mod_proxy_balancer.c

   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
   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 /* Load balancer module for Apache proxy */
  18
  19 #include "mod_proxy.h"
  20 #include "scoreboard.h"
  21 #include "ap_mpm.h"
  22 #include "apr_version.h"
  23 #include "ap_hooks.h"
  24 #include "apr_date.h"
  25
  26 static const char *balancer_mutex_type = "proxy-balancer-shm";
  27 ap_slotmem_provider_t *storage = NULL;
  28
  29 module AP_MODULE_DECLARE_DATA proxy_balancer_module;
  30
  31 /*
  32  * Register our mutex type before the config is read so we
  33  * can adjust the mutex settings using the Mutex directive.
  34  */
  35 static int balancer_pre_config(apr_pool_t *pconf, apr_pool_t *plog,
  36                                apr_pool_t *ptemp)
  37 {
  38
  39     apr_status_t rv;
  40
  41     rv = ap_mutex_register(pconf, balancer_mutex_type, NULL,
  42                                APR_LOCK_DEFAULT, 0);
  43     if (rv != APR_SUCCESS) {
  44         return rv;
  45     }
  46
  47     return OK;
  48 }
  49
  50 #if 0
  51 extern void proxy_update_members(proxy_balancer **balancer, request_rec *r,
  52                                  proxy_server_conf *conf);
  53 #endif
  54
  55 static int proxy_balancer_canon(request_rec *r, char *url)
  56 {
  57     char *host, *path;
  58     char *search = NULL;
  59     const char *err;
  60     apr_port_t port = 0;
  61
  62     /* TODO: offset of BALANCER_PREFIX ?? */
  63     if (strncasecmp(url, "balancer:", 9) == 0) {
  64         url += 9;
  65     }
  66     else {
  67         return DECLINED;
  68     }
  69
  70     ap_log_error(APLOG_MARK, APLOG_TRACE1, 0, r->server,
  71              "proxy: BALANCER: canonicalising URL %s", url);
  72
  73     /* do syntatic check.
  74      * We break the URL into host, port, path, search
  75      */
  76     err = ap_proxy_canon_netloc(r->pool, &url, NULL, NULL, &host, &port);
  77     if (err) {
  78         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
  79                       "error parsing URL %s: %s",
  80                       url, err);
  81         return HTTP_BAD_REQUEST;
  82     }
  83     /*
  84      * now parse path/search args, according to rfc1738:
  85      * process the path. With proxy-noncanon set (by
  86      * mod_proxy) we use the raw, unparsed uri
  87      */
  88     if (apr_table_get(r->notes, "proxy-nocanon")) {
  89         path = url;   /* this is the raw path */
  90     }
  91     else {
  92         path = ap_proxy_canonenc(r->pool, url, strlen(url), enc_path, 0,
  93                                  r->proxyreq);
  94         search = r->args;
  95     }
  96     if (path == NULL)
  97         return HTTP_BAD_REQUEST;
  98
  99     r->filename = apr_pstrcat(r->pool, "proxy:", BALANCER_PREFIX, host,
 100             "/", path, (search) ? "?" : "", (search) ? search : "", NULL);
 101
 102     r->path_info = apr_pstrcat(r->pool, "/", path, NULL);
 103
 104     return OK;
 105 }
 106
 107 static void init_balancer_members(apr_pool_t *p, server_rec *s,
 108                                  proxy_balancer *balancer)
 109 {
 110     int i;
 111     proxy_worker **workers;
 112
 113     workers = (proxy_worker **)balancer->workers->elts;
 114
 115     for (i = 0; i < balancer->workers->nelts; i++) {
 116         int worker_is_initialized;
 117         proxy_worker *worker = *workers;
 118         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
 119                      "Looking at %s -> %s initialized?", balancer->name, worker->s->name);
 120         worker_is_initialized = PROXY_WORKER_IS_INITIALIZED(worker);
 121         if (!worker_is_initialized) {
 122             ap_proxy_initialize_worker(worker, s, p);
 123         }
 124         ++workers;
 125     }
 126
 127     /* Set default number of attempts to the number of
 128      * workers.
 129      */
 130     if (!balancer->s->max_attempts_set && balancer->workers->nelts > 1) {
 131         balancer->s->max_attempts = balancer->workers->nelts - 1;
 132         balancer->s->max_attempts_set = 1;
 133     }
 134 }
 135
 136 /* Retrieve the parameter with the given name
 137  * Something like 'JSESSIONID=12345...N'
 138  */
 139 static char *get_path_param(apr_pool_t *pool, char *url,
 140                             const char *name, int scolon_sep)
 141 {
 142     char *path = NULL;
 143     char *pathdelims = "?&";
 144
 145     if (scolon_sep) {
 146         pathdelims = ";?&";
 147     }
 148     for (path = strstr(url, name); path; path = strstr(path + 1, name)) {
 149         path += strlen(name);
 150         if (*path == '=') {
 151             /*
 152              * Session path was found, get its value
 153              */
 154             ++path;
 155             if (*path) {
 156                 char *q;
 157                 path = apr_strtok(apr_pstrdup(pool, path), pathdelims, &q);
 158                 return path;
 159             }
 160         }
 161     }
 162     return NULL;
 163 }
 164
 165 static char *get_cookie_param(request_rec *r, const char *name)
 166 {
 167     const char *cookies;
 168     const char *start_cookie;
 169
 170     if ((cookies = apr_table_get(r->headers_in, "Cookie"))) {
 171         for (start_cookie = ap_strstr_c(cookies, name); start_cookie;
 172              start_cookie = ap_strstr_c(start_cookie + 1, name)) {
 173             if (start_cookie == cookies ||
 174                 start_cookie[-1] == ';' ||
 175                 start_cookie[-1] == ',' ||
 176                 isspace(start_cookie[-1])) {
 177
 178                 start_cookie += strlen(name);
 179                 while(*start_cookie && isspace(*start_cookie))
 180                     ++start_cookie;
 181                 if (*start_cookie++ == '=' && *start_cookie) {
 182                     /*
 183                      * Session cookie was found, get its value
 184                      */
 185                     char *end_cookie, *cookie;
 186                     cookie = apr_pstrdup(r->pool, start_cookie);
 187                     if ((end_cookie = strchr(cookie, ';')) != NULL)
 188                         *end_cookie = '\0';
 189                     if((end_cookie = strchr(cookie, ',')) != NULL)
 190                         *end_cookie = '\0';
 191                     return cookie;
 192                 }
 193             }
 194         }
 195     }
 196     return NULL;
 197 }
 198
 199 /* Find the worker that has the 'route' defined
 200  */
 201 static proxy_worker *find_route_worker(proxy_balancer *balancer,
 202                                        const char *route, request_rec *r)
 203 {
 204     int i;
 205     int checking_standby;
 206     int checked_standby;
 207
 208     proxy_worker **workers;
 209
 210     checking_standby = checked_standby = 0;
 211     while (!checked_standby) {
 212         workers = (proxy_worker **)balancer->workers->elts;
 213         for (i = 0; i < balancer->workers->nelts; i++, workers++) {
 214             proxy_worker *worker = *workers;
 215             if ( (checking_standby ? !PROXY_WORKER_IS_STANDBY(worker) : PROXY_WORKER_IS_STANDBY(worker)) )
 216                 continue;
 217             if (*(worker->s->route) && strcmp(worker->s->route, route) == 0) {
 218                 if (worker && PROXY_WORKER_IS_USABLE(worker)) {
 219                     return worker;
 220                 } else {
 221                     /*
 222                      * If the worker is in error state run
 223                      * retry on that worker. It will be marked as
 224                      * operational if the retry timeout is elapsed.
 225                      * The worker might still be unusable, but we try
 226                      * anyway.
 227                      */
 228                     ap_proxy_retry_worker("BALANCER", worker, r->server);
 229                     if (PROXY_WORKER_IS_USABLE(worker)) {
 230                             return worker;
 231                     } else {
 232                         /*
 233                          * We have a worker that is unusable.
 234                          * It can be in error or disabled, but in case
 235                          * it has a redirection set use that redirection worker.
 236                          * This enables to safely remove the member from the
 237                          * balancer. Of course you will need some kind of
 238                          * session replication between those two remote.
 239                          */
 240                         if (*worker->s->redirect) {
 241                             proxy_worker *rworker = NULL;
 242                             rworker = find_route_worker(balancer, worker->s->redirect, r);
 243                             /* Check if the redirect worker is usable */
 244                             if (rworker && !PROXY_WORKER_IS_USABLE(rworker)) {
 245                                 /*
 246                                  * If the worker is in error state run
 247                                  * retry on that worker. It will be marked as
 248                                  * operational if the retry timeout is elapsed.
 249                                  * The worker might still be unusable, but we try
 250                                  * anyway.
 251                                  */
 252                                 ap_proxy_retry_worker("BALANCER", rworker, r->server);
 253                             }
 254                             if (rworker && PROXY_WORKER_IS_USABLE(rworker))
 255                                 return rworker;
 256                         }
 257                     }
 258                 }
 259             }
 260         }
 261         checked_standby = checking_standby++;
 262     }
 263     return NULL;
 264 }
 265
 266 static proxy_worker *find_session_route(proxy_balancer *balancer,
 267                                         request_rec *r,
 268                                         char **route,
 269                                         const char **sticky_used,
 270                                         char **url)
 271 {
 272     proxy_worker *worker = NULL;
 273
 274     if (!*balancer->s->sticky)
 275         return NULL;
 276     /* Try to find the sticky route inside url */
 277     *route = get_path_param(r->pool, *url, balancer->s->sticky_path, balancer->s->scolonsep);
 278     if (*route) {
 279         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 280                      "proxy: BALANCER: Found value %s for "
 281                      "stickysession %s", *route, balancer->s->sticky_path);
 282         *sticky_used =  balancer->s->sticky_path;
 283     }
 284     else {
 285         *route = get_cookie_param(r, balancer->s->sticky);
 286         if (*route) {
 287             *sticky_used =  balancer->s->sticky;
 288             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 289                          "proxy: BALANCER: Found value %s for "
 290                          "stickysession %s", *route, balancer->s->sticky);
 291         }
 292     }
 293     /*
 294      * If we found a value for sticksession, find the first '.' within.
 295      * Everything after '.' (if present) is our route.
 296      */
 297     if ((*route) && ((*route = strchr(*route, '.')) != NULL ))
 298         (*route)++;
 299     if ((*route) && (**route)) {
 300         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 301                                   "proxy: BALANCER: Found route %s", *route);
 302         /* We have a route in path or in cookie
 303          * Find the worker that has this route defined.
 304          */
 305         worker = find_route_worker(balancer, *route, r);
 306         if (worker && strcmp(*route, worker->s->route)) {
 307             /*
 308              * Notice that the route of the worker chosen is different from
 309              * the route supplied by the client.
 310              */
 311             apr_table_setn(r->subprocess_env, "BALANCER_ROUTE_CHANGED", "1");
 312             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 313                          "proxy: BALANCER: Route changed from %s to %s",
 314                          *route, worker->s->route);
 315         }
 316         return worker;
 317     }
 318     else
 319         return NULL;
 320 }
 321
 322 static proxy_worker *find_best_worker(proxy_balancer *balancer,
 323                                       request_rec *r)
 324 {
 325     proxy_worker *candidate = NULL;
 326     apr_status_t rv;
 327
 328     if ((rv = PROXY_THREAD_LOCK(balancer)) != APR_SUCCESS) {
 329         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 330         "proxy: BALANCER: (%s). Lock failed for find_best_worker()", balancer->name);
 331         return NULL;
 332     }
 333
 334     candidate = (*balancer->lbmethod->finder)(balancer, r);
 335
 336     if (candidate)
 337         candidate->s->elected++;
 338
 339     if ((rv = PROXY_THREAD_UNLOCK(balancer)) != APR_SUCCESS) {
 340         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 341         "proxy: BALANCER: (%s). Unlock failed for find_best_worker()", balancer->name);
 342     }
 343
 344     if (candidate == NULL) {
 345         /* All the workers are in error state or disabled.
 346          * If the balancer has a timeout sleep for a while
 347          * and try again to find the worker. The chances are
 348          * that some other thread will release a connection.
 349          * By default the timeout is not set, and the server
 350          * returns SERVER_BUSY.
 351          */
 352         if (balancer->s->timeout) {
 353             /* XXX: This can perhaps be build using some
 354              * smarter mechanism, like tread_cond.
 355              * But since the statuses can came from
 356              * different childs, use the provided algo.
 357              */
 358             apr_interval_time_t timeout = balancer->s->timeout;
 359             apr_interval_time_t step, tval = 0;
 360             /* Set the timeout to 0 so that we don't
 361              * end in infinite loop
 362              */
 363             balancer->s->timeout = 0;
 364             step = timeout / 100;
 365             while (tval < timeout) {
 366                 apr_sleep(step);
 367                 /* Try again */
 368                 if ((candidate = find_best_worker(balancer, r)))
 369                     break;
 370                 tval += step;
 371             }
 372             /* restore the timeout */
 373             balancer->s->timeout = timeout;
 374         }
 375     }
 376
 377     return candidate;
 378
 379 }
 380
 381 static int rewrite_url(request_rec *r, proxy_worker *worker,
 382                         char **url)
 383 {
 384     const char *scheme = strstr(*url, "://");
 385     const char *path = NULL;
 386
 387     if (scheme)
 388         path = ap_strchr_c(scheme + 3, '/');
 389
 390     /* we break the URL into host, port, uri */
 391     if (!worker) {
 392         return ap_proxyerror(r, HTTP_BAD_REQUEST, apr_pstrcat(r->pool,
 393                              "missing worker. URI cannot be parsed: ", *url,
 394                              NULL));
 395     }
 396
 397     *url = apr_pstrcat(r->pool, worker->s->name, path, NULL);
 398
 399     return OK;
 400 }
 401
 402 static void force_recovery(proxy_balancer *balancer, server_rec *s)
 403 {
 404     int i;
 405     int ok = 0;
 406     proxy_worker **worker;
 407
 408     worker = (proxy_worker **)balancer->workers->elts;
 409     for (i = 0; i < balancer->workers->nelts; i++, worker++) {
 410         if (!((*worker)->s->status & PROXY_WORKER_IN_ERROR)) {
 411             ok = 1;
 412             break;
 413         }
 414         else {
 415             /* Try if we can recover */
 416             ap_proxy_retry_worker("BALANCER", *worker, s);
 417             if (!((*worker)->s->status & PROXY_WORKER_IN_ERROR)) {
 418                 ok = 1;
 419                 break;
 420             }
 421         }
 422     }
 423     if (!ok) {
 424         /* If all workers are in error state force the recovery.
 425          */
 426         worker = (proxy_worker **)balancer->workers->elts;
 427         for (i = 0; i < balancer->workers->nelts; i++, worker++) {
 428             ++(*worker)->s->retries;
 429             (*worker)->s->status &= ~PROXY_WORKER_IN_ERROR;
 430             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s,
 431                          "proxy: BALANCER: (%s). Forcing recovery for worker (%s)",
 432                          balancer->name, (*worker)->s->hostname);
 433         }
 434     }
 435 }
 436
 437 static int proxy_balancer_pre_request(proxy_worker **worker,
 438                                       proxy_balancer **balancer,
 439                                       request_rec *r,
 440                                       proxy_server_conf *conf, char **url)
 441 {
 442     int access_status;
 443     proxy_worker *runtime;
 444     char *route = NULL;
 445     const char *sticky = NULL;
 446     apr_status_t rv;
 447
 448     *worker = NULL;
 449     /* Step 1: check if the url is for us
 450      * The url we can handle starts with 'balancer://'
 451      * If balancer is already provided skip the search
 452      * for balancer, because this is failover attempt.
 453      */
 454     if (!*balancer &&
 455         !(*balancer = ap_proxy_get_balancer(r->pool, conf, *url)))
 456         return DECLINED;
 457
 458     /* Step 2: Lock the LoadBalancer
 459      * XXX: perhaps we need the process lock here
 460      */
 461     if ((rv = PROXY_THREAD_LOCK(*balancer)) != APR_SUCCESS) {
 462         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 463                      "proxy: BALANCER: (%s). Lock failed for pre_request",
 464                      (*balancer)->name);
 465         return DECLINED;
 466     }
 467
 468     /* Step 3: force recovery */
 469     force_recovery(*balancer, r->server);
 470
 471     /* Step 3.5: Update member list for the balancer */
 472     /* TODO: Implement as provider! */
 473     ap_proxy_sync_balancer(*balancer, r->server, conf);
 474
 475     /* Step 4: find the session route */
 476     runtime = find_session_route(*balancer, r, &route, &sticky, url);
 477     if (runtime) {
 478         if ((*balancer)->lbmethod && (*balancer)->lbmethod->updatelbstatus) {
 479             /* Call the LB implementation */
 480             (*balancer)->lbmethod->updatelbstatus(*balancer, runtime, r->server);
 481         }
 482         else { /* Use the default one */
 483             int i, total_factor = 0;
 484             proxy_worker **workers;
 485             /* We have a sticky load balancer
 486              * Update the workers status
 487              * so that even session routes get
 488              * into account.
 489              */
 490             workers = (proxy_worker **)(*balancer)->workers->elts;
 491             for (i = 0; i < (*balancer)->workers->nelts; i++) {
 492                 /* Take into calculation only the workers that are
 493                  * not in error state or not disabled.
 494                  */
 495                 if (PROXY_WORKER_IS_USABLE(*workers)) {
 496                     (*workers)->s->lbstatus += (*workers)->s->lbfactor;
 497                     total_factor += (*workers)->s->lbfactor;
 498                 }
 499                 workers++;
 500             }
 501             runtime->s->lbstatus -= total_factor;
 502         }
 503         runtime->s->elected++;
 504
 505         *worker = runtime;
 506     }
 507     else if (route && (*balancer)->s->sticky_force) {
 508         int i, member_of = 0;
 509         proxy_worker **workers;
 510         /*
 511          * We have a route provided that doesn't match the
 512          * balancer name. See if the provider route is the
 513          * member of the same balancer in which case return 503
 514          */
 515         workers = (proxy_worker **)(*balancer)->workers->elts;
 516         for (i = 0; i < (*balancer)->workers->nelts; i++) {
 517             if (*((*workers)->s->route) && strcmp((*workers)->s->route, route) == 0) {
 518                 member_of = 1;
 519                 break;
 520             }
 521             workers++;
 522         }
 523         if (member_of) {
 524             ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
 525                          "proxy: BALANCER: (%s). All workers are in error state for route (%s)",
 526                          (*balancer)->name, route);
 527             if ((rv = PROXY_THREAD_UNLOCK(*balancer)) != APR_SUCCESS) {
 528                 ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 529                              "proxy: BALANCER: (%s). Unlock failed for pre_request",
 530                              (*balancer)->name);
 531             }
 532             return HTTP_SERVICE_UNAVAILABLE;
 533         }
 534     }
 535
 536     if ((rv = PROXY_THREAD_UNLOCK(*balancer)) != APR_SUCCESS) {
 537         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 538                      "proxy: BALANCER: (%s). Unlock failed for pre_request",
 539                      (*balancer)->name);
 540     }
 541     if (!*worker) {
 542         runtime = find_best_worker(*balancer, r);
 543         if (!runtime) {
 544             if ((*balancer)->workers->nelts) {
 545                 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
 546                             "proxy: BALANCER: (%s). All workers are in error state",
 547                             (*balancer)->name);
 548             } else {
 549                 ap_log_error(APLOG_MARK, APLOG_ERR, 0, r->server,
 550                             "proxy: BALANCER: (%s). No workers in balancer",
 551                             (*balancer)->name);
 552             }
 553
 554             return HTTP_SERVICE_UNAVAILABLE;
 555         }
 556         if (*(*balancer)->s->sticky && runtime) {
 557             /*
 558              * This balancer has sticky sessions and the client either has not
 559              * supplied any routing information or all workers for this route
 560              * including possible redirect and hotstandby workers are in error
 561              * state, but we have found another working worker for this
 562              * balancer where we can send the request. Thus notice that we have
 563              * changed the route to the backend.
 564              */
 565             apr_table_setn(r->subprocess_env, "BALANCER_ROUTE_CHANGED", "1");
 566         }
 567         *worker = runtime;
 568     }
 569
 570     (*worker)->s->busy++;
 571
 572     /* Add balancer/worker info to env. */
 573     apr_table_setn(r->subprocess_env,
 574                    "BALANCER_NAME", (*balancer)->name);
 575     apr_table_setn(r->subprocess_env,
 576                    "BALANCER_WORKER_NAME", (*worker)->s->name);
 577     apr_table_setn(r->subprocess_env,
 578                    "BALANCER_WORKER_ROUTE", (*worker)->s->route);
 579
 580     /* Rewrite the url from 'balancer://url'
 581      * to the 'worker_scheme://worker_hostname[:worker_port]/url'
 582      * This replaces the balancers fictional name with the
 583      * real hostname of the elected worker.
 584      */
 585     access_status = rewrite_url(r, *worker, url);
 586     /* Add the session route to request notes if present */
 587     if (route) {
 588         apr_table_setn(r->notes, "session-sticky", sticky);
 589         apr_table_setn(r->notes, "session-route", route);
 590
 591         /* Add session info to env. */
 592         apr_table_setn(r->subprocess_env,
 593                        "BALANCER_SESSION_STICKY", sticky);
 594         apr_table_setn(r->subprocess_env,
 595                        "BALANCER_SESSION_ROUTE", route);
 596     }
 597     ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 598                  "proxy: BALANCER (%s) worker (%s) rewritten to %s",
 599                  (*balancer)->name, (*worker)->s->name, *url);
 600
 601     return access_status;
 602 }
 603
 604 static int proxy_balancer_post_request(proxy_worker *worker,
 605                                        proxy_balancer *balancer,
 606                                        request_rec *r,
 607                                        proxy_server_conf *conf)
 608 {
 609
 610     apr_status_t rv;
 611
 612     if ((rv = PROXY_THREAD_LOCK(balancer)) != APR_SUCCESS) {
 613         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 614             "proxy: BALANCER: (%s). Lock failed for post_request",
 615             balancer->name);
 616         return HTTP_INTERNAL_SERVER_ERROR;
 617     }
 618
 619     if (!apr_is_empty_array(balancer->errstatuses)) {
 620         int i;
 621         for (i = 0; i < balancer->errstatuses->nelts; i++) {
 622             int val = ((int *)balancer->errstatuses->elts)[i];
 623             if (r->status == val) {
 624                 ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 625                              "proxy: BALANCER: (%s).  Forcing recovery for worker (%s), failonstatus %d",
 626                              balancer->name, worker->s->name, val);
 627                 worker->s->status |= PROXY_WORKER_IN_ERROR;
 628                 worker->s->error_time = apr_time_now();
 629                 break;
 630             }
 631         }
 632     }
 633
 634     if ((rv = PROXY_THREAD_UNLOCK(balancer)) != APR_SUCCESS) {
 635         ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 636             "proxy: BALANCER: (%s). Unlock failed for post_request",
 637             balancer->name);
 638     }
 639     ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server,
 640                  "proxy_balancer_post_request for (%s)", balancer->name);
 641
 642     if (worker && worker->s->busy)
 643         worker->s->busy--;
 644
 645     return OK;
 646
 647 }
 648
 649 static void recalc_factors(proxy_balancer *balancer)
 650 {
 651     int i;
 652     proxy_worker **workers;
 653
 654
 655     /* Recalculate lbfactors */
 656     workers = (proxy_worker **)balancer->workers->elts;
 657     /* Special case if there is only one worker its
 658      * load factor will always be 1
 659      */
 660     if (balancer->workers->nelts == 1) {
 661         (*workers)->s->lbstatus = (*workers)->s->lbfactor = 1;
 662         return;
 663     }
 664     for (i = 0; i < balancer->workers->nelts; i++) {
 665         /* Update the status entries */
 666         workers[i]->s->lbstatus = workers[i]->s->lbfactor;
 667     }
 668 }
 669
 670 static apr_status_t lock_remove(void *data)
 671 {
 672     int i;
 673     proxy_balancer *balancer;
 674     server_rec *s = data;
 675     void *sconf = s->module_config;
 676     proxy_server_conf *conf = (proxy_server_conf *) ap_get_module_config(sconf, &proxy_module);
 677
 678     balancer = (proxy_balancer *)conf->balancers->elts;
 679     for (i = 0; i < conf->balancers->nelts; i++, balancer++) {
 680         if (balancer->gmutex) {
 681             apr_global_mutex_destroy(balancer->gmutex);
 682             balancer->gmutex = NULL;
 683         }
 684     }
 685     return(0);
 686 }
 687
 688 /* post_config hook: */
 689 static int balancer_post_config(apr_pool_t *pconf, apr_pool_t *plog,
 690                          apr_pool_t *ptemp, server_rec *s)
 691 {
 692     apr_status_t rv;
 693     void *sconf = s->module_config;
 694     proxy_server_conf *conf = (proxy_server_conf *) ap_get_module_config(sconf, &proxy_module);
 695     ap_slotmem_instance_t *new = NULL;
 696     apr_time_t tstamp;
 697
 698     /* balancer_post_config() will be called twice during startup.  So, don't
 699      * set up the static data the 1st time through. */
 700     if (ap_state_query(AP_SQ_MAIN_STATE) == AP_SQ_MS_CREATE_PRE_CONFIG)
 701         return OK;
 702
 703     /*
 704      * Get slotmem setups
 705      */
 706     storage = ap_lookup_provider(AP_SLOTMEM_PROVIDER_GROUP, "shared",
 707                                  AP_SLOTMEM_PROVIDER_VERSION);
 708     if (!storage) {
 709         ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, 0, s,
 710                      "ap_lookup_provider %s failed: is mod_slotmem_shm loaded??",
 711                      AP_SLOTMEM_PROVIDER_GROUP);
 712         return !OK;
 713     }
 714
 715     tstamp = apr_time_now();
 716     /*
 717      * Go thru each Vhost and create the shared mem slotmem for
 718      * each balancer's workers
 719      */
 720     while (s) {
 721         int i,j;
 722         proxy_balancer *balancer;
 723         sconf = s->module_config;
 724         conf = (proxy_server_conf *)ap_get_module_config(sconf, &proxy_module);
 725
 726         if (conf->balancers->nelts) {
 727             conf->max_balancers = conf->balancers->nelts + conf->bgrowth;
 728             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "Doing balancers create: %d, %d (%d)",
 729                          (int)ALIGNED_PROXY_BALANCER_SHARED_SIZE,
 730                          (int)conf->balancers->nelts, conf->max_balancers);
 731
 732             rv = storage->create(&new, conf->id,
 733                                  ALIGNED_PROXY_BALANCER_SHARED_SIZE,
 734                                  conf->max_balancers, AP_SLOTMEM_TYPE_PREGRAB, pconf);
 735             if (rv != APR_SUCCESS) {
 736                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "balancer slotmem_create failed");
 737                 return !OK;
 738             }
 739             conf->slot = new;
 740         }
 741         conf->storage = storage;
 742
 743         /* Initialize shared scoreboard data */
 744         balancer = (proxy_balancer *)conf->balancers->elts;
 745         for (i = 0; i < conf->balancers->nelts; i++, balancer++) {
 746             proxy_worker **workers;
 747             proxy_worker *worker;
 748             proxy_balancer_shared *bshm;
 749             unsigned int index;
 750
 751             balancer->max_workers = balancer->workers->nelts + balancer->growth;
 752             /* no need for the 'balancer://' prefix */
 753             ap_pstr2_alnum(pconf, balancer->name + sizeof(BALANCER_PREFIX) - 1,
 754                            &balancer->sname);
 755             balancer->sname = apr_pstrcat(pconf, conf->id, "_", balancer->sname, NULL);
 756
 757             /* Create global mutex */
 758             rv = ap_global_mutex_create(&(balancer->gmutex), NULL, balancer_mutex_type,
 759                                         balancer->sname, s, pconf, 0);
 760             if (rv != APR_SUCCESS || !balancer->gmutex) {
 761                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s,
 762                              "mutex creation of %s : %s failed", balancer_mutex_type,
 763                              balancer->sname);
 764                 return HTTP_INTERNAL_SERVER_ERROR;
 765             }
 766
 767             apr_pool_cleanup_register(pconf, (void *)s, lock_remove,
 768                                       apr_pool_cleanup_null);
 769
 770             /* setup shm for balancers */
 771             if ((rv = storage->grab(conf->slot, &index)) != APR_SUCCESS) {
 772                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "balancer slotmem_grab failed");
 773                 return !OK;
 774
 775             }
 776             if ((rv = storage->dptr(conf->slot, index, (void *)&bshm)) != APR_SUCCESS) {
 777                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "balancer slotmem_dptr failed");
 778                 return !OK;
 779             }
 780             if ((rv = ap_proxy_share_balancer(balancer, bshm, index)) != APR_SUCCESS) {
 781                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "Cannot share balancer");
 782                 return !OK;
 783             }
 784
 785             /* create slotmem slots for workers */
 786             ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, s, "Doing workers create: %s (%s), %d, %d",
 787                          balancer->name, balancer->sname,
 788                          (int)ALIGNED_PROXY_WORKER_SHARED_SIZE,
 789                          (int)balancer->max_workers);
 790
 791             rv = storage->create(&new, balancer->sname,
 792                                  ALIGNED_PROXY_WORKER_SHARED_SIZE,
 793                                  balancer->max_workers, AP_SLOTMEM_TYPE_PREGRAB, pconf);
 794             if (rv != APR_SUCCESS) {
 795                 ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "worker slotmem_create failed");
 796                 return !OK;
 797             }
 798             balancer->slot = new;
 799             balancer->storage = storage;
 800
 801             /* sync all timestamps */
 802             balancer->wupdated = balancer->s->wupdated = tstamp;
 803
 804             /* now go thru each worker */
 805             workers = (proxy_worker **)balancer->workers->elts;
 806             for (j = 0; j < balancer->workers->nelts; j++, workers++) {
 807                 proxy_worker_shared *shm;
 808
 809                 worker = *workers;
 810                 if ((rv = storage->grab(balancer->slot, &index)) != APR_SUCCESS) {
 811                     ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "worker slotmem_grab failed");
 812                     return !OK;
 813
 814                 }
 815                 if ((rv = storage->dptr(balancer->slot, index, (void *)&shm)) != APR_SUCCESS) {
 816                     ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "worker slotmem_dptr failed");
 817                     return !OK;
 818                 }
 819                 if ((rv = ap_proxy_share_worker(worker, shm, index)) != APR_SUCCESS) {
 820                     ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "Cannot share worker");
 821                     return !OK;
 822                 }
 823                 worker->s->updated = tstamp;
 824             }
 825         }
 826         s = s->next;
 827     }
 828
 829     return OK;
 830 }
 831
 832 static void create_radio(const char *name, unsigned int flag, request_rec *r)
 833 {
 834     ap_rvputs(r, "<td>On <input name='", name, "' id='", name, "' value='1' type=radio", NULL);
 835     if (flag)
 836         ap_rputs(" checked", r);
 837     ap_rvputs(r, "> <br/> Off <input name='", name, "' id='", name, "' value='0' type=radio", NULL);
 838     if (!flag)
 839         ap_rputs(" checked", r);
 840     ap_rputs("></td>\n", r);
 841 }
 842
 843 static void push2table(const char *input, apr_table_t *params,
 844                        const char *allowed[], apr_pool_t *p)
 845 {
 846     char *args;
 847     char *tok, *val;
 848     char *key;
 849
 850     if (input == NULL) {
 851         return;
 852     }
 853     args = apr_pstrdup(p, input);
 854
 855     key = apr_strtok(args, "&", &tok);
 856     while (key) {
 857         val = strchr(key, '=');
 858         if (val) {
 859             *val++ = '\0';
 860         }
 861         else {
 862             val = "";
 863         }
 864         ap_unescape_url(key);
 865         ap_unescape_url(val);
 866         if (allowed == NULL) { /* allow all */
 867             apr_table_set(params, key, val);
 868         }
 869         else {
 870             const char *ok = *allowed;
 871             while (ok) {
 872                 if (strcmp(ok, key) == 0) {
 873                     apr_table_set(params, key, val);
 874                     break;
 875                 }
 876                 ok++;
 877             }
 878         }
 879         key = apr_strtok(NULL, "&", &tok);
 880     }
 881 }
 882
 883 /* Manages the loadfactors and member status
 884  *   The balancer, worker and nonce are obtained from
 885  *   the request args (?b=...&w=...&nonce=....).
 886  *   All other params are pulled from any POST
 887  *   data that exists.
 888  * TODO:
 889  *   /.../<whatever>/balancer/worker/nonce
 890  */
 891 static int balancer_handler(request_rec *r)
 892 {
 893     void *sconf;
 894     proxy_server_conf *conf;
 895     proxy_balancer *balancer, *bsel = NULL;
 896     proxy_worker *worker, *wsel = NULL;
 897     proxy_worker **workers = NULL;
 898     apr_table_t *params;
 899     int i, n;
 900     int ok2change = 1;
 901     const char *name;
 902     const char *action;
 903     apr_status_t rv;
 904
 905     /* is this for us? */
 906     if (strcmp(r->handler, "balancer-manager")) {
 907         return DECLINED;
 908     }
 909
 910     r->allowed = 0
 911     | (AP_METHOD_BIT << M_GET)
 912     | (AP_METHOD_BIT << M_POST);
 913     if ((r->method_number != M_GET) && (r->method_number != M_POST)) {
 914         return DECLINED;
 915     }
 916
 917     sconf = r->server->module_config;
 918     conf = (proxy_server_conf *) ap_get_module_config(sconf, &proxy_module);
 919     params = apr_table_make(r->pool, 10);
 920
 921     balancer = (proxy_balancer *)conf->balancers->elts;
 922     for (i = 0; i < conf->balancers->nelts; i++, balancer++) {
 923         if ((rv = PROXY_THREAD_LOCK(balancer)) != APR_SUCCESS) {
 924             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 925                          "proxy: BALANCER: (%s). Lock failed for balancer_handler",
 926                          balancer->name);
 927         }
 928         ap_proxy_sync_balancer(balancer, r->server, conf);
 929         if ((rv = PROXY_THREAD_UNLOCK(balancer)) != APR_SUCCESS) {
 930             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
 931                          "proxy: BALANCER: (%s). Unlock failed for balancer_handler",
 932                          balancer->name);
 933         }
 934     }
 935
 936     if (r->args && (r->method_number == M_GET)) {
 937         const char *allowed[] = { "w", "b", "nonce", NULL };
 938         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "parsing r->args");
 939
 940         push2table(r->args, params, allowed, r->pool);
 941     }
 942     if (r->method_number == M_POST) {
 943         apr_bucket_brigade *ib;
 944         apr_size_t len = 1024;
 945         char *buf = apr_pcalloc(r->pool, len+1);
 946
 947         ib = apr_brigade_create(r->connection->pool, r->connection->bucket_alloc);
 948         rv = ap_get_brigade(r->input_filters, ib, AP_MODE_READBYTES,
 949                                 APR_BLOCK_READ, len);
 950         if (rv != APR_SUCCESS) {
 951             return HTTP_INTERNAL_SERVER_ERROR;
 952         }
 953         apr_brigade_flatten(ib, buf, &len);
 954         buf[len] = '\0';
 955         push2table(buf, params, NULL, r->pool);
 956     }
 957     if ((name = apr_table_get(params, "b")))
 958         bsel = ap_proxy_get_balancer(r->pool, conf,
 959             apr_pstrcat(r->pool, BALANCER_PREFIX, name, NULL));
 960
 961     if ((name = apr_table_get(params, "w"))) {
 962         wsel = ap_proxy_get_worker(r->pool, bsel, conf, name);
 963     }
 964
 965
 966     /* Check that the supplied nonce matches this server's nonce;
 967      * otherwise ignore all parameters, to prevent a CSRF attack. */
 968     if (!bsel ||
 969         (*bsel->s->nonce &&
 970          (
 971           (name = apr_table_get(params, "nonce")) == NULL ||
 972           strcmp(bsel->s->nonce, name) != 0
 973          )
 974         )
 975        ) {
 976         apr_table_clear(params);
 977         ok2change = 0;
 978     }
 979
 980     /* First set the params */
 981     if (wsel && ok2change) {
 982         const char *val;
 983         int was_usable = PROXY_WORKER_IS_USABLE(wsel);
 984
 985         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "settings worker params");
 986
 987         if ((val = apr_table_get(params, "w_lf"))) {
 988             int ival = atoi(val);
 989             if (ival >= 1 && ival <= 100) {
 990                 wsel->s->lbfactor = ival;
 991                 if (bsel)
 992                     recalc_factors(bsel);
 993             }
 994         }
 995         if ((val = apr_table_get(params, "w_wr"))) {
 996             if (strlen(val) && strlen(val) < sizeof(wsel->s->route))
 997                 strcpy(wsel->s->route, val);
 998             else
 999                 *wsel->s->route = '\0';
1000         }
1001         if ((val = apr_table_get(params, "w_rr"))) {
1002             if (strlen(val) && strlen(val) < sizeof(wsel->s->redirect))
1003                 strcpy(wsel->s->redirect, val);
1004             else
1005                 *wsel->s->redirect = '\0';
1006         }
1007         if ((val = apr_table_get(params, "w_status_I"))) {
1008             ap_proxy_set_wstatus('I', atoi(val), wsel);
1009         }
1010         if ((val = apr_table_get(params, "w_status_N"))) {
1011             ap_proxy_set_wstatus('N', atoi(val), wsel);
1012         }
1013         if ((val = apr_table_get(params, "w_status_D"))) {
1014             ap_proxy_set_wstatus('D', atoi(val), wsel);
1015         }
1016         if ((val = apr_table_get(params, "w_status_H"))) {
1017             ap_proxy_set_wstatus('H', atoi(val), wsel);
1018         }
1019         if ((val = apr_table_get(params, "w_ls"))) {
1020             int ival = atoi(val);
1021             if (ival >= 0 && ival <= 99) {
1022                 wsel->s->lbset = ival;
1023              }
1024         }
1025         /* if enabling, we need to reset all lb params */
1026         if (bsel && !was_usable && PROXY_WORKER_IS_USABLE(wsel)) {
1027             bsel->s->need_reset = 1;
1028         }
1029
1030     }
1031
1032     if (bsel && ok2change) {
1033         const char *val;
1034         int ival;
1035         ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "settings balancer params");
1036         if ((val = apr_table_get(params, "b_lbm"))) {
1037             if ((strlen(val) < (sizeof(bsel->s->lbpname)-1)) &&
1038                 strcmp(val, bsel->s->lbpname)) {
1039                 proxy_balancer_method *lbmethod;
1040                 lbmethod = ap_lookup_provider(PROXY_LBMETHOD, val, "0");
1041                 if (lbmethod) {
1042                     PROXY_STRNCPY(bsel->s->lbpname, val);
1043                     bsel->lbmethod = lbmethod;
1044                     bsel->s->wupdated = apr_time_now();
1045                     bsel->s->need_reset = 1;
1046                 }
1047             }
1048         }
1049         if ((val = apr_table_get(params, "b_tmo"))) {
1050             ival = atoi(val);
1051             if (ival >= 0 && ival <= 7200) { /* 2 hrs enuff? */
1052                 bsel->s->timeout = apr_time_from_sec(ival);
1053             }
1054         }
1055         if ((val = apr_table_get(params, "b_max"))) {
1056             ival = atoi(val);
1057             if (ival >= 0 && ival <= 99) {
1058                 bsel->s->max_attempts = ival;
1059             }
1060         }
1061         if ((val = apr_table_get(params, "b_sforce"))) {
1062             ival = atoi(val);
1063             bsel->s->sticky_force = (ival != 0);
1064         }
1065         if ((val = apr_table_get(params, "b_ss")) && *val) {
1066             if (strlen(val) < (sizeof(bsel->s->sticky_path)-1)) {
1067                 if (*val == '-' && *(val+1) == '\0')
1068                     *bsel->s->sticky_path = *bsel->s->sticky = '\0';
1069                 else {
1070                     char *path;
1071                     PROXY_STRNCPY(bsel->s->sticky_path, val);
1072                     PROXY_STRNCPY(bsel->s->sticky, val);
1073
1074                     if ((path = strchr((char *)bsel->s->sticky, '|'))) {
1075                         *path++ = '\0';
1076                         PROXY_STRNCPY(bsel->s->sticky_path, path);
1077                     }
1078                 }
1079             }
1080         }
1081         if ((val = apr_table_get(params, "b_wyes")) &&
1082             (*val == '1' && *(val+1) == '\0') &&
1083             (val = apr_table_get(params, "b_nwrkr"))) {
1084             char *ret;
1085             proxy_worker *nworker;
1086             nworker = ap_proxy_get_worker(conf->pool, bsel, conf, val);
1087             if (!nworker && storage->num_free_slots(bsel->slot)) {
1088                 if ((rv = PROXY_GLOBAL_LOCK(bsel)) != APR_SUCCESS) {
1089                     ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1090                                  "proxy: BALANCER: (%s). Lock failed for adding worker",
1091                                  bsel->name);
1092                 }
1093                 ret = ap_proxy_define_worker(conf->pool, &nworker, bsel, conf, val, 0);
1094                 if (!ret) {
1095                     unsigned int index;
1096                     proxy_worker_shared *shm;
1097                     PROXY_COPY_CONF_PARAMS(nworker, conf);
1098                     if ((rv = storage->grab(bsel->slot, &index)) != APR_SUCCESS) {
1099                         ap_log_error(APLOG_MARK, APLOG_EMERG, rv, r->server, "worker slotmem_grab failed");
1100                         if ((rv = PROXY_GLOBAL_UNLOCK(bsel)) != APR_SUCCESS) {
1101                             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1102                                          "proxy: BALANCER: (%s). Unlock failed for adding worker",
1103                                          bsel->name);
1104                         }
1105                         return HTTP_BAD_REQUEST;
1106                     }
1107                     if ((rv = storage->dptr(bsel->slot, index, (void *)&shm)) != APR_SUCCESS) {
1108                         ap_log_error(APLOG_MARK, APLOG_EMERG, rv, r->server, "worker slotmem_dptr failed");
1109                         if ((rv = PROXY_GLOBAL_UNLOCK(bsel)) != APR_SUCCESS) {
1110                             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1111                                          "proxy: BALANCER: (%s). Unlock failed for adding worker",
1112                                          bsel->name);
1113                         }
1114                         return HTTP_BAD_REQUEST;
1115                     }
1116                     if ((rv = ap_proxy_share_worker(nworker, shm, index)) != APR_SUCCESS) {
1117                         ap_log_error(APLOG_MARK, APLOG_EMERG, rv, r->server, "Cannot share worker");
1118                         if ((rv = PROXY_GLOBAL_UNLOCK(bsel)) != APR_SUCCESS) {
1119                             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1120                                          "proxy: BALANCER: (%s). Unlock failed for adding worker",
1121                                          bsel->name);
1122                         }
1123                         return HTTP_BAD_REQUEST;
1124                     }
1125                     if ((rv = ap_proxy_initialize_worker(nworker, r->server, conf->pool)) != APR_SUCCESS) {
1126                         ap_log_error(APLOG_MARK, APLOG_EMERG, rv, r->server, "Cannot init worker");
1127                         if ((rv = PROXY_GLOBAL_UNLOCK(bsel)) != APR_SUCCESS) {
1128                             ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1129                                          "proxy: BALANCER: (%s). Unlock failed for adding worker",
1130                                          bsel->name);
1131                         }
1132                         return HTTP_BAD_REQUEST;
1133                     }
1134                     /* sync all timestamps */
1135                     bsel->wupdated = bsel->s->wupdated = nworker->s->updated = apr_time_now();
1136                     /* by default, all new workers are disabled */
1137                     ap_proxy_set_wstatus('D', 1, nworker);
1138                 }
1139                 if ((rv = PROXY_GLOBAL_UNLOCK(bsel)) != APR_SUCCESS) {
1140                     ap_log_error(APLOG_MARK, APLOG_ERR, rv, r->server,
1141                                  "proxy: BALANCER: (%s). Unlock failed for adding worker",
1142                                  bsel->name);
1143                 }
1144             }
1145
1146         }
1147
1148     }
1149
1150     action = ap_construct_url(r->pool, r->uri, r);
1151     ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, r->server, "genning page");
1152
1153     if (apr_table_get(params, "xml")) {
1154         ap_set_content_type(r, "text/xml");
1155         ap_rputs("<?xml version='1.0' encoding='UTF-8' ?>\n", r);
1156         ap_rputs("<httpd:manager xmlns:httpd='http://httpd.apache.org'>\n", r);
1157         ap_rputs("  <httpd:balancers>\n", r);
1158         balancer = (proxy_balancer *)conf->balancers->elts;
1159         for (i = 0; i < conf->balancers->nelts; i++) {
1160             ap_rputs("    <httpd:balancer>\n", r);
1161             ap_rvputs(r, "      <httpd:name>", balancer->name, "</httpd:name>\n", NULL);
1162             ap_rputs("      <httpd:workers>\n", r);
1163             workers = (proxy_worker **)balancer->workers->elts;
1164             for (n = 0; n < balancer->workers->nelts; n++) {
1165                 worker = *workers;
1166                 ap_rputs("        <httpd:worker>\n", r);
1167                 ap_rvputs(r, "          <httpd:scheme>", worker->s->scheme,
1168                           "</httpd:scheme>\n", NULL);
1169                 ap_rvputs(r, "          <httpd:hostname>", worker->s->hostname,
1170                           "</httpd:hostname>\n", NULL);
1171                 ap_rprintf(r, "          <httpd:loadfactor>%d</httpd:loadfactor>\n",
1172                           worker->s->lbfactor);
1173                 ap_rputs("        </httpd:worker>\n", r);
1174                 ++workers;
1175             }
1176             ap_rputs("      </httpd:workers>\n", r);
1177             ap_rputs("    </httpd:balancer>\n", r);
1178             ++balancer;
1179         }
1180         ap_rputs("  </httpd:balancers>\n", r);
1181         ap_rputs("</httpd:manager>", r);
1182     }
1183     else {
1184         ap_set_content_type(r, "text/html; charset=ISO-8859-1");
1185         ap_rputs(DOCTYPE_HTML_3_2
1186                  "<html><head><title>Balancer Manager</title></head>\n", r);
1187         ap_rputs("<body><h1>Load Balancer Manager for ", r);
1188         ap_rvputs(r, ap_get_server_name(r), "</h1>\n\n", NULL);
1189         ap_rvputs(r, "<dl><dt>Server Version: ",
1190                   ap_get_server_description(), "</dt>\n", NULL);
1191         ap_rvputs(r, "<dt>Server Built: ",
1192                   ap_get_server_built(), "\n</dt></dl>\n", NULL);
1193         balancer = (proxy_balancer *)conf->balancers->elts;
1194         for (i = 0; i < conf->balancers->nelts; i++) {
1195
1196             ap_rputs("<hr />\n<h3>LoadBalancer Status for ", r);
1197             ap_rvputs(r, "<a href='", r->uri, "?b=",
1198                       balancer->name + sizeof(BALANCER_PREFIX) - 1,
1199                       "&nonce=", balancer->s->nonce,
1200                       "'>", NULL);
1201             ap_rvputs(r, balancer->name, "</a></h3>\n\n", NULL);
1202             ap_rputs("\n\n<table border='0' style='text-align: left;'><tr>"
1203                 "<th>MaxMembers</th><th>StickySession</th><th>DisableFailover</th><th>Timeout</th><th>FailoverAttempts</th><th>Method</th>"
1204                 "</tr>\n<tr>", r);
1205             /* the below is a safe cast, since the number of slots total will
1206              * never be more than max_workers, which is restricted to int */
1207             ap_rprintf(r, "<td align='center'>%d [%d Used]</td>\n", balancer->max_workers,
1208                        balancer->max_workers - (int)storage->num_free_slots(balancer->slot));
1209             if (*balancer->s->sticky) {
1210                 if (strcmp(balancer->s->sticky, balancer->s->sticky_path)) {
1211                     ap_rvputs(r, "<td align='center'>", balancer->s->sticky, " | ",
1212                               balancer->s->sticky_path, NULL);
1213                 }
1214                 else {
1215                     ap_rvputs(r, "<td align='center'>", balancer->s->sticky, NULL);
1216                 }
1217             }
1218             else {
1219                 ap_rputs("<td align='center'> (None) ", r);
1220             }
1221             ap_rprintf(r, "<td align='center'>%s</td>\n",
1222                        balancer->s->sticky_force ? "On" : "Off");
1223             ap_rprintf(r, "</td><td align='center'>%" APR_TIME_T_FMT "</td>",
1224                 apr_time_sec(balancer->s->timeout));
1225             ap_rprintf(r, "<td align='center'>%d</td>\n", balancer->s->max_attempts);
1226             ap_rprintf(r, "<td align='center'>%s</td>\n",
1227                        balancer->s->lbpname);
1228             ap_rputs("</table>\n<br />", r);
1229             ap_rputs("\n\n<table border='0' style='text-align: left;'><tr>"
1230                 "<th>Worker URL</th>"
1231                 "<th>Route</th><th>RouteRedir</th>"
1232                 "<th>Factor</th><th>Set</th><th align='center'>Status</th>"
1233                 "<th>Elected</th><th>Busy</th><th>Load</th><th>To</th><th>From</th>"
1234                 "</tr>\n", r);
1235
1236             workers = (proxy_worker **)balancer->workers->elts;
1237             for (n = 0; n < balancer->workers->nelts; n++) {
1238                 char fbuf[50];
1239                 worker = *workers;
1240                 ap_rvputs(r, "<tr>\n<td><a href='", r->uri, "?b=",
1241                           balancer->name + sizeof(BALANCER_PREFIX) - 1, "&w=",
1242                           ap_escape_uri(r->pool, worker->s->name),
1243                           "&nonce=", balancer->s->nonce,
1244                           "'>", NULL);
1245                 ap_rvputs(r, worker->s->name, "</a></td>", NULL);
1246                 ap_rvputs(r, "<td align='center'>", ap_escape_html(r->pool, worker->s->route),
1247                           NULL);
1248                 ap_rvputs(r, "</td><td align='center'>",
1249                           ap_escape_html(r->pool, worker->s->redirect), NULL);
1250                 ap_rprintf(r, "</td><td align='center'>%d</td>", worker->s->lbfactor);
1251                 ap_rprintf(r, "<td align='center'>%d</td><td align='center'>", worker->s->lbset);
1252                 ap_rvputs(r, ap_proxy_parse_wstatus(r->pool, worker), NULL);
1253                 ap_rputs("</td>", r);
1254                 ap_rprintf(r, "<td align='center'>%" APR_SIZE_T_FMT "</td>", worker->s->elected);
1255                 ap_rprintf(r, "<td align='center'>%" APR_SIZE_T_FMT "</td>", worker->s->busy);
1256                 ap_rprintf(r, "<td align='center'>%d</td><td align='center'>", worker->s->lbstatus);
1257                 ap_rputs(apr_strfsize(worker->s->transferred, fbuf), r);
1258                 ap_rputs("</td><td align='center'>", r);
1259                 ap_rputs(apr_strfsize(worker->s->read, fbuf), r);
1260                 ap_rputs("</td></tr>\n", r);
1261
1262                 ++workers;
1263             }
1264             ap_rputs("</table>\n", r);
1265             ++balancer;
1266         }
1267         ap_rputs("<hr />\n", r);
1268         if (wsel && bsel) {
1269             ap_rputs("<h3>Edit worker settings for ", r);
1270             ap_rvputs(r, wsel->s->name, "</h3>\n", NULL);
1271             ap_rputs("<form method='POST' enctype='application/x-www-form-urlencoded' action='", r);
1272             ap_rvputs(r, action, "'>\n", NULL);
1273             ap_rputs("<dl>\n<table><tr><td>Load factor:</td><td><input name='w_lf' id='w_lf' type=text ", r);
1274             ap_rprintf(r, "value='%d'></td></tr>\n", wsel->s->lbfactor);
1275             ap_rputs("<tr><td>LB Set:</td><td><input name='w_ls' id='w_ls' type=text ", r);
1276             ap_rprintf(r, "value='%d'></td></tr>\n", wsel->s->lbset);
1277             ap_rputs("<tr><td>Route:</td><td><input name='w_wr' id='w_wr' type=text ", r);
1278             ap_rvputs(r, "value='", ap_escape_html(r->pool, wsel->s->route),
1279                       NULL);
1280             ap_rputs("'></td></tr>\n", r);
1281             ap_rputs("<tr><td>Route Redirect:</td><td><input name='w_rr' id='w_rr' type=text ", r);
1282             ap_rvputs(r, "value='", ap_escape_html(r->pool, wsel->s->redirect),
1283                       NULL);
1284             ap_rputs("'></td></tr>\n", r);
1285             ap_rputs("<tr><td>Status:</td>", r);
1286             ap_rputs("<td><table border='1'><tr><th>Ign</th><th>Drn</th><th>Dis</th><th>Stby</th></tr>\n<tr>", r);
1287             create_radio("w_status_I", (PROXY_WORKER_IGNORE_ERRORS & wsel->s->status), r);
1288             create_radio("w_status_N", (PROXY_WORKER_DRAIN & wsel->s->status), r);
1289             create_radio("w_status_D", (PROXY_WORKER_DISABLED & wsel->s->status), r);
1290             create_radio("w_status_H", (PROXY_WORKER_HOT_STANDBY & wsel->s->status), r);
1291             ap_rputs("</tr></table>\n", r);
1292             ap_rputs("<tr><td colspan=2><input type=submit value='Submit'></td></tr>\n", r);
1293             ap_rvputs(r, "</table>\n<input type=hidden name='w' id='w' ",  NULL);
1294             ap_rvputs(r, "value='", ap_escape_uri(r->pool, wsel->s->name), "'>\n", NULL);
1295             ap_rvputs(r, "<input type=hidden name='b' id='b' ", NULL);
1296             ap_rvputs(r, "value='", bsel->name + sizeof(BALANCER_PREFIX) - 1,
1297                       "'>\n", NULL);
1298             ap_rvputs(r, "<input type=hidden name='nonce' id='nonce' value='",
1299                       bsel->s->nonce, "'>\n", NULL);
1300             ap_rvputs(r, "</form>\n", NULL);
1301             ap_rputs("<hr />\n", r);
1302         } else if (bsel) {
1303             const apr_array_header_t *provs;
1304             const ap_list_provider_names_t *pname;
1305             int i;
1306             ap_rputs("<h3>Edit balancer settings for ", r);
1307             ap_rvputs(r, bsel->name, "</h3>\n", NULL);
1308             ap_rputs("<form method='POST' enctype='application/x-www-form-urlencoded' action='", r);
1309             ap_rvputs(r, action, "'>\n", NULL);
1310             ap_rputs("<dl>\n<table>\n", r);
1311             provs = ap_list_provider_names(r->pool, PROXY_LBMETHOD, "0");
1312             if (provs) {
1313                 ap_rputs("<tr><td>LBmethod:</td>", r);
1314                 ap_rputs("<td>\n<select name='b_lbm' id='b_lbm'>", r);
1315                 pname = (ap_list_provider_names_t *)provs->elts;
1316                 for (i = 0; i < provs->nelts; i++, pname++) {
1317                     ap_rvputs(r,"<option value='", pname->provider_name, "'", NULL);
1318                     if (strcmp(pname->provider_name, bsel->s->lbpname) == 0)
1319                         ap_rputs(" selected ", r);
1320                     ap_rvputs(r, ">", pname->provider_name, "\n", NULL);
1321                 }
1322                 ap_rputs("</select>\n</td></tr>\n", r);
1323             }
1324             ap_rputs("<tr><td>Timeout:</td><td><input name='b_tmo' id='b_tmo' type=text ", r);
1325             ap_rprintf(r, "value='%" APR_TIME_T_FMT "'></td></tr>\n", apr_time_sec(bsel->s->timeout));
1326             ap_rputs("<tr><td>Failover Attempts:</td><td><input name='b_max' id='b_max' type=text ", r);
1327             ap_rprintf(r, "value='%d'></td></tr>\n", bsel->s->max_attempts);
1328             ap_rputs("<tr><td>Disable Failover:</td>", r);
1329             create_radio("b_sforce", bsel->s->sticky_force, r);
1330             ap_rputs("<tr><td>Sticky Session:</td><td><input name='b_ss' id='b_ss' size=64 type=text ", r);
1331             if (strcmp(bsel->s->sticky, bsel->s->sticky_path)) {
1332                 ap_rvputs(r, "value ='", bsel->s->sticky, " | ",
1333                           bsel->s->sticky_path, NULL);
1334             }
1335             else {
1336                 ap_rvputs(r, "value ='", bsel->s->sticky, NULL);
1337             }
1338             ap_rputs("'>&nbsp;&nbsp;&nbsp;&nbsp;(Use '-' to delete)</td></tr>\n", r);
1339             if (storage->num_free_slots(bsel->slot) != 0) {
1340                 ap_rputs("<tr><td>Add New Worker:</td><td><input name='b_nwrkr' id='b_nwrkr' size=32 type=text>"
1341                          "&nbsp;&nbsp;&nbsp;&nbsp;Are you sure? <input name='b_wyes' id='b_wyes' type=checkbox value='1'>"
1342                          "</td></tr>", r);
1343             }
1344             ap_rputs("<tr><td colspan=2><input type=submit value='Submit'></td></tr>\n", r);
1345             ap_rvputs(r, "</table>\n<input type=hidden name='b' id='b' ", NULL);
1346             ap_rvputs(r, "value='", bsel->name + sizeof(BALANCER_PREFIX) - 1,
1347                       "'>\n", NULL);
1348             ap_rvputs(r, "<input type=hidden name='nonce' id='nonce' value='",
1349                       bsel->s->nonce, "'>\n", NULL);
1350             ap_rvputs(r, "</form>\n", NULL);
1351             ap_rputs("<hr />\n", r);
1352         }
1353         ap_rputs(ap_psignature("",r), r);
1354         ap_rputs("</body></html>\n", r);
1355         ap_rflush(r);
1356     }
1357     return DONE;
1358 }
1359
1360 static void balancer_child_init(apr_pool_t *p, server_rec *s)
1361 {
1362     while (s) {
1363         proxy_balancer *balancer;
1364         int i;
1365         void *sconf = s->module_config;
1366         proxy_server_conf *conf = (proxy_server_conf *)ap_get_module_config(sconf, &proxy_module);
1367         apr_status_t rv;
1368
1369         if (conf->balancers->nelts) {
1370             apr_size_t size;
1371             unsigned int num;
1372             storage->attach(&(conf->slot), conf->id, &size, &num, p);
1373             if (!conf->slot) {
1374                 ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_EMERG, 0, s, "slotmem_attach failed");
1375                 exit(1); /* Ugly, but what else? */
1376             }
1377         }
1378
1379         balancer = (proxy_balancer *)conf->balancers->elts;
1380         for (i = 0; i < conf->balancers->nelts; i++, balancer++) {
1381             rv = ap_proxy_initialize_balancer(balancer, s, p);
1382
1383             if (rv != APR_SUCCESS) {
1384                 ap_log_error(APLOG_MARK, APLOG_CRIT, rv, s,
1385                              "Failed to init balancer %s in child",
1386                              balancer->name);
1387                 exit(1); /* Ugly, but what else? */
1388             }
1389             init_balancer_members(conf->pool, s, balancer);
1390         }
1391         s = s->next;
1392     }
1393
1394 }
1395
1396 static void ap_proxy_balancer_register_hook(apr_pool_t *p)
1397 {
1398     /* Only the mpm_winnt has child init hook handler.
1399      * make sure that we are called after the mpm
1400      * initializes
1401      */
1402     static const char *const aszPred[] = { "mpm_winnt.c", "mod_slotmem_shm.c", NULL};
1403      /* manager handler */
1404     ap_hook_post_config(balancer_post_config, NULL, NULL, APR_HOOK_MIDDLE);
1405     ap_hook_pre_config(balancer_pre_config, NULL, NULL, APR_HOOK_MIDDLE);
1406     ap_hook_handler(balancer_handler, NULL, NULL, APR_HOOK_FIRST);
1407     ap_hook_child_init(balancer_child_init, aszPred, NULL, APR_HOOK_MIDDLE);
1408     proxy_hook_pre_request(proxy_balancer_pre_request, NULL, NULL, APR_HOOK_FIRST);
1409     proxy_hook_post_request(proxy_balancer_post_request, NULL, NULL, APR_HOOK_FIRST);
1410     proxy_hook_canon_handler(proxy_balancer_canon, NULL, NULL, APR_HOOK_FIRST);
1411 }
1412
1413 AP_DECLARE_MODULE(proxy_balancer) = {
1414     STANDARD20_MODULE_STUFF,
1415     NULL,       /* create per-directory config structure */
1416     NULL,       /* merge per-directory config structures */
1417     NULL,       /* create per-server config structure */
1418     NULL,       /* merge per-server config structures */
1419     NULL,       /* command apr_table_t */
1420     ap_proxy_balancer_register_hook /* register hooks */
1421 };