/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "apr_hash.h" #include "apr_strings.h" #include "apr_pools.h" #include "apr_portable.h" #include "apr_file_io.h" #include "apr_signal.h" #define APR_WANT_IOVEC #include "apr_want.h" #if APR_HAVE_UNISTD_H #include #endif #if APR_HAVE_SYS_SOCKET_H #include #endif #if !APR_HAS_THREADS #error The perchild MPM requires APR threads, but they are unavailable. #endif #define CORE_PRIVATE #include "ap_config.h" #include "httpd.h" #include "http_main.h" #include "http_log.h" #include "http_config.h" /* for read_config */ #include "http_core.h" /* for get_remote_host */ #include "http_protocol.h" #include "http_connection.h" #include "ap_mpm.h" #include "unixd.h" #include "mpm_common.h" #include "ap_listen.h" #include "mpm_default.h" #include "mpm.h" #include "scoreboard.h" #include "util_filter.h" #include "apr_poll.h" #ifdef HAVE_POLL_H #include #endif #ifdef HAVE_SYS_POLL_H #include #endif /* ### should be APR-ized */ #include #include #include #include #include #ifdef HAVE_SYS_PROCESSOR_H #include /* for bindprocessor() */ #endif /* * Define some magic numbers that we use for the state of the incomming * request. These must be < 0 so they don't collide with a file descriptor. */ #define AP_PERCHILD_THISCHILD -1 #define AP_PERCHILD_OTHERCHILD -2 /* Limit on the threads per process. Clients will be locked out if more than * this * server_limit are needed. * * We keep this for one reason it keeps the size of the scoreboard file small * enough that we can read the whole thing without worrying too much about * the overhead. */ #ifndef DEFAULT_THREAD_LIMIT #define DEFAULT_THREAD_LIMIT 64 #endif /* Admin can't tune ThreadLimit beyond MAX_THREAD_LIMIT. We want * some sort of compile-time limit to help catch typos. */ #ifndef MAX_THREAD_LIMIT #define MAX_THREAD_LIMIT 20000 #endif /* Limit on the total --- clients will be locked out if more servers than * this are needed. It is intended solely to keep the server from crashing * when things get out of hand. * * We keep a hard maximum number of servers, for two reasons --- first off, * in case something goes seriously wrong, we want to stop the fork bomb * short of actually crashing the machine we're running on by filling some * kernel table. Secondly, it keeps the size of the scoreboard file small * enough that we can read the whole thing without worrying too much about * the overhead. */ #ifndef DEFAULT_SERVER_LIMIT #define DEFAULT_SERVER_LIMIT 8 #endif /* Admin can't tune ServerLimit beyond MAX_SERVER_LIMIT. We want * some sort of compile-time limit to help catch typos. */ #ifndef MAX_SERVER_LIMIT #define MAX_SERVER_LIMIT 20000 #endif /* * Actual definitions of config globals */ static int threads_to_start = 0; /* Worker threads per child */ static int min_spare_threads = 0; static int max_spare_threads = 0; static int max_threads = 0; static int server_limit = DEFAULT_SERVER_LIMIT; static int first_server_limit; static int thread_limit = DEFAULT_THREAD_LIMIT; static int first_thread_limit; static int changed_limit_at_restart; static int num_daemons = 0; static int curr_child_num = 0; static int workers_may_exit = 0; static int requests_this_child; static int num_listensocks = 0; static ap_pod_t *pod; static jmp_buf jmpbuffer; struct child_info_t { uid_t uid; gid_t gid; int input; /* The socket descriptor */ int output; /* The socket descriptor */ }; typedef struct { const char *sockname; /* The base name for the socket */ const char *fullsockname; /* socket base name + extension */ int input; /* The socket descriptor */ int output; /* The socket descriptor */ } perchild_server_conf; typedef struct child_info_t child_info_t; /* Tables used to determine the user and group each child process should * run as. The hash table is used to correlate a server name with a child * process. */ static child_info_t *child_info_table; static int *thread_socket_table; struct ap_ctable *ap_child_table; /* * The max child slot ever assigned, preserved across restarts. Necessary * to deal with NumServers changes across AP_SIG_GRACEFUL restarts. We * use this value to optimize routines that have to scan the entire child * table. * * XXX - It might not be worth keeping this code in. There aren't very * many child processes in this MPM. */ int ap_max_daemons_limit = -1; int ap_threads_per_child; /* XXX not part of API! axe it! */ module AP_MODULE_DECLARE_DATA mpm_perchild_module; static apr_file_t *pipe_of_death_in = NULL; static apr_file_t *pipe_of_death_out = NULL; static apr_thread_mutex_t *pipe_of_death_mutex; /* *Non*-shared http_main globals... */ server_rec *ap_server_conf; /* one_process --- debugging mode variable; can be set from the command line * with the -X flag. If set, this gets you the child_main loop running * in the process which originally started up (no detach, no make_child), * which is a pretty nice debugging environment. (You'll get a SIGHUP * early in standalone_main; just continue through. This is the server * trying to kill off any child processes which it might have lying * around --- Apache doesn't keep track of their pids, it just sends * SIGHUP to the process group, ignoring it in the root process. * Continue through and you'll be fine.). */ static int one_process = 0; #ifdef DEBUG_SIGSTOP int raise_sigstop_flags; #endif static apr_pool_t *pconf; /* Pool for config stuff */ static apr_pool_t *pchild; /* Pool for httpd child stuff */ static apr_pool_t *thread_pool_parent; /* Parent of per-thread pools */ static apr_thread_mutex_t *thread_pool_parent_mutex; static int child_num; static unsigned int my_pid; /* Linux getpid() doesn't work except in main thread. Use this instead */ /* Keep track of the number of worker threads currently active */ static int worker_thread_count; static apr_thread_mutex_t *worker_thread_count_mutex; static int *worker_thread_free_ids; static apr_threadattr_t *worker_thread_attr; /* Keep track of the number of idle worker threads */ static int idle_thread_count; static apr_thread_mutex_t *idle_thread_count_mutex; /* Locks for accept serialization */ #ifdef NO_SERIALIZED_ACCEPT #define SAFE_ACCEPT(stmt) APR_SUCCESS #else #define SAFE_ACCEPT(stmt) (stmt) static apr_proc_mutex_t *process_accept_mutex; #endif /* NO_SERIALIZED_ACCEPT */ static apr_thread_mutex_t *thread_accept_mutex; AP_DECLARE(apr_status_t) ap_mpm_query(int query_code, int *result) { switch(query_code){ case AP_MPMQ_MAX_DAEMON_USED: *result = ap_max_daemons_limit; return APR_SUCCESS; case AP_MPMQ_IS_THREADED: *result = AP_MPMQ_DYNAMIC; return APR_SUCCESS; case AP_MPMQ_IS_FORKED: *result = AP_MPMQ_STATIC; return APR_SUCCESS; case AP_MPMQ_HARD_LIMIT_DAEMONS: *result = server_limit; return APR_SUCCESS; case AP_MPMQ_HARD_LIMIT_THREADS: *result = thread_limit; return APR_SUCCESS; case AP_MPMQ_MAX_THREADS: *result = max_threads; return APR_SUCCESS; case AP_MPMQ_MIN_SPARE_DAEMONS: *result = 0; return APR_SUCCESS; case AP_MPMQ_MIN_SPARE_THREADS: *result = min_spare_threads; return APR_SUCCESS; case AP_MPMQ_MAX_SPARE_DAEMONS: *result = 0; return APR_SUCCESS; case AP_MPMQ_MAX_SPARE_THREADS: *result = max_spare_threads; return APR_SUCCESS; case AP_MPMQ_MAX_REQUESTS_DAEMON: *result = ap_max_requests_per_child; return APR_SUCCESS; case AP_MPMQ_MAX_DAEMONS: *result = num_daemons; return APR_SUCCESS; } return APR_ENOTIMPL; } /* a clean exit from a child with proper cleanup */ static void clean_child_exit(int code) { if (pchild) { apr_pool_destroy(pchild); } exit(code); } static void just_die(int sig) { clean_child_exit(0); } /***************************************************************** * Connection structures and accounting... */ /* volatile just in case */ static int volatile shutdown_pending; static int volatile restart_pending; static int volatile is_graceful; static int volatile child_fatal; /* we don't currently track ap_my_generation, but mod_status * references it so it must be defined */ ap_generation_t volatile ap_my_generation=0; /* * ap_start_shutdown() and ap_start_restart(), below, are a first stab at * functions to initiate shutdown or restart without relying on signals. * Previously this was initiated in sig_term() and restart() signal handlers, * but we want to be able to start a shutdown/restart from other sources -- * e.g. on Win32, from the service manager. Now the service manager can * call ap_start_shutdown() or ap_start_restart() as appropiate. Note that * these functions can also be called by the child processes, since global * variables are no longer used to pass on the required action to the parent. * * These should only be called from the parent process itself, since the * parent process will use the shutdown_pending and restart_pending variables * to determine whether to shutdown or restart. The child process should * call signal_parent() directly to tell the parent to die -- this will * cause neither of those variable to be set, which the parent will * assume means something serious is wrong (which it will be, for the * child to force an exit) and so do an exit anyway. */ static void ap_start_shutdown(void) { if (shutdown_pending == 1) { /* Um, is this _probably_ not an error, if the user has * tried to do a shutdown twice quickly, so we won't * worry about reporting it. */ return; } shutdown_pending = 1; } /* do a graceful restart if graceful == 1 */ static void ap_start_restart(int graceful) { if (restart_pending == 1) { /* Probably not an error - don't bother reporting it */ return; } restart_pending = 1; is_graceful = graceful; } static void sig_term(int sig) { ap_start_shutdown(); } static void restart(int sig) { #ifndef WIN32 ap_start_restart(sig == AP_SIG_GRACEFUL); #else ap_start_restart(1); #endif } static void set_signals(void) { #ifndef NO_USE_SIGACTION struct sigaction sa; #endif if (!one_process) { ap_fatal_signal_setup(ap_server_conf, pconf); } #ifndef NO_USE_SIGACTION sigemptyset(&sa.sa_mask); sa.sa_flags = 0; sa.sa_handler = sig_term; if (sigaction(SIGTERM, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGTERM)"); #ifdef SIGINT if (sigaction(SIGINT, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGINT)"); #endif #ifdef SIGXCPU sa.sa_handler = SIG_DFL; if (sigaction(SIGXCPU, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXCPU)"); #endif #ifdef SIGXFSZ sa.sa_handler = SIG_DFL; if (sigaction(SIGXFSZ, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGXFSZ)"); #endif #ifdef SIGPIPE sa.sa_handler = SIG_IGN; if (sigaction(SIGPIPE, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGPIPE)"); #endif /* we want to ignore HUPs and AP_SIG_GRACEFUL while we're busy * processing one */ sigaddset(&sa.sa_mask, SIGHUP); sigaddset(&sa.sa_mask, AP_SIG_GRACEFUL); sa.sa_handler = restart; if (sigaction(SIGHUP, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(SIGHUP)"); if (sigaction(AP_SIG_GRACEFUL, &sa, NULL) < 0) ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "sigaction(" AP_SIG_GRACEFUL_STRING ")"); #else if (!one_process) { #ifdef SIGXCPU apr_signal(SIGXCPU, SIG_DFL); #endif /* SIGXCPU */ #ifdef SIGXFSZ apr_signal(SIGXFSZ, SIG_DFL); #endif /* SIGXFSZ */ } apr_signal(SIGTERM, sig_term); #ifdef SIGHUP apr_signal(SIGHUP, restart); #endif /* SIGHUP */ #ifdef AP_SIG_GRACEFUL apr_signal(AP_SIG_GRACEFUL, restart); #endif /* AP_SIG_GRACEFUL */ #ifdef SIGPIPE apr_signal(SIGPIPE, SIG_IGN); #endif /* SIGPIPE */ #endif } /***************************************************************** * Here follows a long bunch of generic server bookkeeping stuff... */ int ap_graceful_stop_signalled(void) { /* XXX - Does this really work? - Manoj */ return is_graceful; } /***************************************************************** * Child process main loop. */ static void process_socket(apr_pool_t *p, apr_socket_t *sock, long conn_id, apr_bucket_alloc_t *bucket_alloc) { conn_rec *current_conn; int csd; apr_status_t rv; int thread_num = conn_id % thread_limit; ap_sb_handle_t *sbh; if ((rv = apr_os_sock_get(&csd, sock)) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, NULL, "apr_os_sock_get"); } if (thread_socket_table[thread_num] < 0) { ap_sock_disable_nagle(sock); } ap_create_sb_handle(&sbh, p, conn_id / thread_limit, thread_num); current_conn = ap_run_create_connection(p, ap_server_conf, sock, conn_id, sbh, bucket_alloc); if (current_conn) { ap_process_connection(current_conn, sock); ap_lingering_close(current_conn); } } static int perchild_process_connection(conn_rec *c) { ap_filter_t *f; apr_bucket_brigade *bb; core_net_rec *net; apr_pool_userdata_get((void **)&bb, "PERCHILD_SOCKETS", c->pool); if (bb != NULL) { for (f = c->output_filters; f != NULL; f = f->next) { if (!strcmp(f->frec->name, "core")) { break; } } if (f != NULL) { net = f->ctx; net->in_ctx = apr_palloc(c->pool, sizeof(*net->in_ctx)); net->in_ctx->b = bb; } } return DECLINED; } static void *worker_thread(apr_thread_t *, void *); /* Starts a thread as long as we're below max_threads */ static int start_thread(void) { apr_thread_t *thread; int rc; apr_thread_mutex_lock(worker_thread_count_mutex); if (worker_thread_count < max_threads - 1) { rc = apr_thread_create(&thread, worker_thread_attr, worker_thread, &worker_thread_free_ids[worker_thread_count], pchild); if (rc != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ALERT, rc, ap_server_conf, "apr_thread_create: unable to create worker thread"); /* In case system resources are maxxed out, we don't want Apache running away with the CPU trying to fork over and over and over again if we exit. */ sleep(10); workers_may_exit = 1; apr_thread_mutex_unlock(worker_thread_count_mutex); return 0; } else { worker_thread_count++; } } else { static int reported = 0; if (!reported) { ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, "server reached MaxThreadsPerChild setting, " "consider raising the MaxThreadsPerChild or " "NumServers settings"); reported = 1; } apr_thread_mutex_unlock(worker_thread_count_mutex); return 0; } apr_thread_mutex_unlock(worker_thread_count_mutex); return 1; } /* Sets workers_may_exit if we received a character on the pipe_of_death */ static apr_status_t check_pipe_of_death(void **csd, ap_listen_rec *lr, apr_pool_t *ptrans) { apr_thread_mutex_lock(pipe_of_death_mutex); if (!workers_may_exit) { int ret; char pipe_read_char; apr_size_t n = 1; ret = apr_recv(lr->sd, &pipe_read_char, &n); if (APR_STATUS_IS_EAGAIN(ret)) { /* It lost the lottery. It must continue to suffer * through a life of servitude. */ } else { /* It won the lottery (or something else is very * wrong). Embrace death with open arms. */ workers_may_exit = 1; } } apr_thread_mutex_unlock(pipe_of_death_mutex); return APR_SUCCESS; } static apr_status_t receive_from_other_child(void **csd, ap_listen_rec *lr, apr_pool_t *ptrans) { struct msghdr msg; struct cmsghdr *cmsg; char buffer[HUGE_STRING_LEN * 2], *headers, *body; int headerslen, bodylen; struct iovec iov; int ret, dp; apr_os_sock_t sd; apr_bucket_alloc_t *alloc = apr_bucket_alloc_create(ptrans); apr_bucket_brigade *bb = apr_brigade_create(ptrans, alloc); apr_bucket *bucket; apr_os_sock_get(&sd, lr->sd); iov.iov_base = buffer; iov.iov_len = sizeof(buffer); msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_iov = &iov; msg.msg_iovlen = 1; cmsg = apr_palloc(ptrans, sizeof(*cmsg) + sizeof(sd)); cmsg->cmsg_len = sizeof(*cmsg) + sizeof(sd); msg.msg_control = cmsg; msg.msg_controllen = cmsg->cmsg_len; ret = recvmsg(sd, &msg, 0); memcpy(&dp, CMSG_DATA(cmsg), sizeof(dp)); *csd = NULL; /* tell apr_os_sock_put() to allocate new apr_socket_t */ apr_os_sock_put((apr_socket_t **)csd, &dp, ptrans); bucket = apr_bucket_eos_create(alloc); APR_BRIGADE_INSERT_HEAD(bb, bucket); bucket = apr_bucket_socket_create(*csd, alloc); APR_BRIGADE_INSERT_HEAD(bb, bucket); body = strchr(iov.iov_base, 0); if (!body) { return 1; } body++; bodylen = strlen(body); headers = iov.iov_base; headerslen = body - headers; bucket = apr_bucket_heap_create(body, bodylen, NULL, alloc); APR_BRIGADE_INSERT_HEAD(bb, bucket); bucket = apr_bucket_heap_create(headers, headerslen, NULL, alloc); APR_BRIGADE_INSERT_HEAD(bb, bucket); apr_pool_userdata_set(bb, "PERCHILD_SOCKETS", NULL, ptrans); return 0; } /* idle_thread_count should be incremented before starting a worker_thread */ static void *worker_thread(apr_thread_t *thd, void *arg) { void *csd; apr_pool_t *tpool; /* Pool for this thread */ apr_pool_t *ptrans; /* Pool for per-transaction stuff */ volatile int thread_just_started = 1; int srv; int thread_num = *((int *) arg); long conn_id = child_num * thread_limit + thread_num; apr_pollfd_t *pollset; apr_status_t rv; ap_listen_rec *lr, *last_lr = ap_listeners; int n; apr_bucket_alloc_t *bucket_alloc; apr_thread_mutex_lock(thread_pool_parent_mutex); apr_pool_create(&tpool, thread_pool_parent); apr_thread_mutex_unlock(thread_pool_parent_mutex); apr_pool_create(&ptrans, tpool); (void) ap_update_child_status_from_indexes(child_num, thread_num, SERVER_STARTING, (request_rec *) NULL); bucket_alloc = apr_bucket_alloc_create(apr_thread_pool_get(thd)); apr_poll_setup(&pollset, num_listensocks, tpool); for(lr = ap_listeners; lr != NULL; lr = lr->next) { int fd; apr_poll_socket_add(pollset, lr->sd, APR_POLLIN); apr_os_sock_get(&fd, lr->sd); } while (!workers_may_exit) { workers_may_exit |= ((ap_max_requests_per_child != 0) && (requests_this_child <= 0)); if (workers_may_exit) break; if (!thread_just_started) { apr_thread_mutex_lock(idle_thread_count_mutex); if (idle_thread_count < max_spare_threads) { idle_thread_count++; apr_thread_mutex_unlock(idle_thread_count_mutex); } else { apr_thread_mutex_unlock(idle_thread_count_mutex); break; } } else { thread_just_started = 0; } (void) ap_update_child_status_from_indexes(child_num, thread_num, SERVER_READY, (request_rec *) NULL); apr_thread_mutex_lock(thread_accept_mutex); if (workers_may_exit) { apr_thread_mutex_unlock(thread_accept_mutex); break; } if ((rv = SAFE_ACCEPT(apr_proc_mutex_lock(process_accept_mutex))) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, "apr_proc_mutex_lock failed. Attempting to shutdown " "process gracefully."); workers_may_exit = 1; } while (!workers_may_exit) { apr_int16_t event; srv = apr_poll(pollset, num_listensocks, &n, -1); if (srv != APR_SUCCESS) { if (APR_STATUS_IS_EINTR(srv)) { continue; } /* apr_poll() will only return errors in catastrophic * circumstances. Let's try exiting gracefully, for now. */ ap_log_error(APLOG_MARK, APLOG_ERR, srv, (const server_rec *) ap_server_conf, "apr_poll: (listen)"); workers_may_exit = 1; } if (workers_may_exit) break; /* find a listener */ lr = last_lr; do { lr = lr->next; if (lr == NULL) { lr = ap_listeners; } /* XXX: Should we check for POLLERR? */ apr_poll_revents_get(&event, lr->sd, pollset); if (event & (APR_POLLIN)) { last_lr = lr; goto got_fd; } } while (lr != last_lr); } got_fd: if (!workers_may_exit) { rv = lr->accept_func(&csd, lr, ptrans); if (rv == APR_EGENERAL) { /* E[NM]FILE, ENOMEM, etc */ workers_may_exit = 1; } if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(process_accept_mutex))) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, "apr_proc_mutex_unlock failed. Attempting to shutdown " "process gracefully."); workers_may_exit = 1; } apr_thread_mutex_unlock(thread_accept_mutex); apr_thread_mutex_lock(idle_thread_count_mutex); if (idle_thread_count > min_spare_threads) { idle_thread_count--; } else { if (!start_thread()) { idle_thread_count--; } } apr_thread_mutex_unlock(idle_thread_count_mutex); if (setjmp(jmpbuffer) != 1) { process_socket(ptrans, csd, conn_id, bucket_alloc); } else { thread_socket_table[thread_num] = AP_PERCHILD_THISCHILD; } requests_this_child--; } else { if ((rv = SAFE_ACCEPT(apr_proc_mutex_unlock(process_accept_mutex))) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, "apr_proc_mutex_unlock failed. Attempting to shutdown " "process gracefully."); workers_may_exit = 1; } apr_thread_mutex_unlock(thread_accept_mutex); apr_thread_mutex_lock(idle_thread_count_mutex); idle_thread_count--; apr_thread_mutex_unlock(idle_thread_count_mutex); break; } apr_pool_clear(ptrans); } apr_thread_mutex_lock(thread_pool_parent_mutex); ap_update_child_status_from_indexes(child_num, thread_num, SERVER_DEAD, (request_rec *) NULL); apr_pool_destroy(tpool); apr_thread_mutex_unlock(thread_pool_parent_mutex); apr_thread_mutex_lock(worker_thread_count_mutex); worker_thread_count--; worker_thread_free_ids[worker_thread_count] = thread_num; if (worker_thread_count == 0) { /* All the threads have exited, now finish the shutdown process * by signalling the sigwait thread */ kill(my_pid, SIGTERM); } apr_thread_mutex_unlock(worker_thread_count_mutex); apr_bucket_alloc_destroy(bucket_alloc); return NULL; } /* Set group privileges. * * Note that we use the username as set in the config files, rather than * the lookup of to uid --- the same uid may have multiple passwd entries, * with different sets of groups for each. */ static int set_group_privs(uid_t uid, gid_t gid) { if (!geteuid()) { const char *name; /* Get username if passed as a uid */ struct passwd *ent; if ((ent = getpwuid(uid)) == NULL) { ap_log_error(APLOG_MARK, APLOG_ALERT, errno, NULL, "getpwuid: couldn't determine user name from uid %u, " "you probably need to modify the User directive", (unsigned)uid); return -1; } name = ent->pw_name; /* * Set the GID before initgroups(), since on some platforms * setgid() is known to zap the group list. */ if (setgid(gid) == -1) { ap_log_error(APLOG_MARK, APLOG_ALERT, errno, NULL, "setgid: unable to set group id to Group %u", (unsigned)gid); return -1; } /* Reset `groups' attributes. */ if (initgroups(name, gid) == -1) { ap_log_error(APLOG_MARK, APLOG_ALERT, errno, NULL, "initgroups: unable to set groups for User %s " "and Group %u", name, (unsigned)gid); return -1; } } return 0; } static int perchild_setup_child(int childnum) { child_info_t *ug = &child_info_table[childnum]; if (ug->uid == -1 && ug->gid == -1) { return unixd_setup_child(); } if (set_group_privs(ug->uid, ug->gid)) { return -1; } /* Only try to switch if we're running as root */ if (!geteuid() && ( #ifdef _OSD_POSIX os_init_job_environment(server_conf, unixd_config.user_name, one_process) != 0 || #endif setuid(ug->uid) == -1)) { ap_log_error(APLOG_MARK, APLOG_ALERT, errno, NULL, "setuid: unable to change to uid: %ld", (long) ug->uid); return -1; } return 0; } static int check_signal(int signum) { switch (signum) { case SIGTERM: case SIGINT: just_die(signum); return 1; } return 0; } typedef struct perchild_header { char *headers; apr_pool_t *p; } perchild_header; /* Send a single HTTP header field to the client. Note that this function * is used in calls to table_do(), so their interfaces are co-dependent. * In other words, don't change this one without checking table_do in alloc.c. * It returns true unless there was a write error of some kind. */ static int perchild_header_field(perchild_header *h, const char *fieldname, const char *fieldval) { apr_pstrcat(h->p, h->headers, fieldname, ": ", fieldval, CRLF, NULL); return 1; } static void child_main(int child_num_arg) { int i; apr_status_t rv; apr_socket_t *sock = NULL; ap_listen_rec *lr; my_pid = getpid(); ap_fatal_signal_child_setup(ap_server_conf); child_num = child_num_arg; apr_pool_create(&pchild, pconf); for (lr = ap_listeners ; lr->next != NULL; lr = lr->next) { continue; } apr_os_sock_put(&sock, &child_info_table[child_num].input, pconf); lr->next = apr_palloc(pconf, sizeof(*lr)); lr->next->sd = sock; lr->next->active = 1; lr->next->accept_func = receive_from_other_child; lr->next->next = NULL; lr = lr->next; num_listensocks++; /*stuff to do before we switch id's, so we have permissions.*/ rv = SAFE_ACCEPT(apr_proc_mutex_child_init(&process_accept_mutex, ap_lock_fname, pchild)); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_EMERG, rv, ap_server_conf, "Couldn't initialize cross-process lock in child"); clean_child_exit(APEXIT_CHILDFATAL); } if (perchild_setup_child(child_num)) { clean_child_exit(APEXIT_CHILDFATAL); } ap_run_child_init(pchild, ap_server_conf); /*done with init critical section */ apr_setup_signal_thread(); requests_this_child = ap_max_requests_per_child; /* Setup worker threads */ if (threads_to_start > max_threads) { threads_to_start = max_threads; } idle_thread_count = threads_to_start; worker_thread_count = 0; worker_thread_free_ids = (int *)apr_pcalloc(pchild, thread_limit * sizeof(int)); for (i = 0; i < max_threads; i++) { worker_thread_free_ids[i] = i; } apr_pool_create(&thread_pool_parent, pchild); apr_thread_mutex_create(&thread_pool_parent_mutex, APR_THREAD_MUTEX_DEFAULT, pchild); apr_thread_mutex_create(&idle_thread_count_mutex, APR_THREAD_MUTEX_DEFAULT, pchild); apr_thread_mutex_create(&worker_thread_count_mutex, APR_THREAD_MUTEX_DEFAULT, pchild); apr_thread_mutex_create(&pipe_of_death_mutex, APR_THREAD_MUTEX_DEFAULT, pchild); apr_thread_mutex_create(&thread_accept_mutex, APR_THREAD_MUTEX_DEFAULT, pchild); apr_threadattr_create(&worker_thread_attr, pchild); apr_threadattr_detach_set(worker_thread_attr, 1); /* We are creating worker threads right now */ for (i=0; i < threads_to_start; i++) { /* start_thread shouldn't fail here */ if (!start_thread()) { break; } } apr_signal_thread(check_signal); } static int make_child(server_rec *s, int slot) { int pid; if (slot + 1 > ap_max_daemons_limit) { ap_max_daemons_limit = slot + 1; } if (one_process) { set_signals(); ap_child_table[slot].pid = getpid(); ap_child_table[slot].status = SERVER_ALIVE; child_main(slot); } (void) ap_update_child_status_from_indexes(slot, 0, SERVER_STARTING, (request_rec *) NULL); if ((pid = fork()) == -1) { ap_log_error(APLOG_MARK, APLOG_ERR, errno, s, "fork: Unable to fork new process"); /* In case system resources are maxxed out, we don't want * Apache running away with the CPU trying to fork over and * over and over again. */ sleep(10); return -1; } if (!pid) { #ifdef HAVE_BINDPROCESSOR /* By default, AIX binds to a single processor. This bit unbinds * children which will then bind to another CPU. */ int status = bindprocessor(BINDPROCESS, (int)getpid(), PROCESSOR_CLASS_ANY); if (status != OK) { ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "processor unbind failed %d", status); } #endif RAISE_SIGSTOP(MAKE_CHILD); /* XXX - For an unthreaded server, a signal handler will be necessary * apr_signal(SIGTERM, just_die); */ child_main(slot); clean_child_exit(0); } /* else */ ap_child_table[slot].pid = pid; ap_child_table[slot].status = SERVER_ALIVE; return 0; } /* start up a bunch of children */ static int startup_children(int number_to_start) { int i; for (i = 0; number_to_start && i < num_daemons; ++i) { if (ap_child_table[i].pid) { continue; } if (make_child(ap_server_conf, i) < 0) { break; } --number_to_start; } return number_to_start; } /* * spawn_rate is the number of children that will be spawned on the * next maintenance cycle if there aren't enough servers. It is * doubled up to MAX_SPAWN_RATE, and reset only when a cycle goes by * without the need to spawn. */ static int spawn_rate = 1; #ifndef MAX_SPAWN_RATE #define MAX_SPAWN_RATE (32) #endif static int hold_off_on_exponential_spawning; static void perform_child_maintenance(void) { int i; int free_length; int free_slots[MAX_SPAWN_RATE]; int last_non_dead = -1; /* initialize the free_list */ free_length = 0; for (i = 0; i < num_daemons; ++i) { if (ap_child_table[i].pid == 0) { if (free_length < spawn_rate) { free_slots[free_length] = i; ++free_length; } } else { last_non_dead = i; } if (i >= ap_max_daemons_limit && free_length >= spawn_rate) { break; } } ap_max_daemons_limit = last_non_dead + 1; if (free_length > 0) { for (i = 0; i < free_length; ++i) { make_child(ap_server_conf, free_slots[i]); } /* the next time around we want to spawn twice as many if this * wasn't good enough, but not if we've just done a graceful */ if (hold_off_on_exponential_spawning) { --hold_off_on_exponential_spawning; } else if (spawn_rate < MAX_SPAWN_RATE) { spawn_rate *= 2; } } else { spawn_rate = 1; } } static void server_main_loop(int remaining_children_to_start) { int child_slot; apr_exit_why_e exitwhy; int status; apr_proc_t pid; int i; while (!restart_pending && !shutdown_pending) { ap_wait_or_timeout(&exitwhy, &status, &pid, pconf); if (pid.pid != -1) { if (ap_process_child_status(&pid, exitwhy, status) == APEXIT_CHILDFATAL) { shutdown_pending = 1; child_fatal = 1; return; } /* non-fatal death... note that it's gone in the child table and * clean out the status table. */ child_slot = -1; for (i = 0; i < ap_max_daemons_limit; ++i) { if (ap_child_table[i].pid == pid.pid) { child_slot = i; break; } } if (child_slot >= 0) { ap_child_table[child_slot].pid = 0; ap_update_child_status_from_indexes(child_slot, i, SERVER_DEAD, (request_rec *) NULL); if (remaining_children_to_start && child_slot < num_daemons) { /* we're still doing a 1-for-1 replacement of dead * children with new children */ make_child(ap_server_conf, child_slot); --remaining_children_to_start; } #if APR_HAS_OTHER_CHILD } else if (apr_proc_other_child_read(&pid, status) == 0) { /* handled */ #endif } else if (is_graceful) { /* Great, we've probably just lost a slot in the * child table. Somehow we don't know about this * child. */ ap_log_error(APLOG_MARK, APLOG_WARNING, 0, ap_server_conf, "long lost child came home! (pid %ld)", (long)pid.pid); } /* Don't perform idle maintenance when a child dies, * only do it when there's a timeout. Remember only a * finite number of children can die, and it's pretty * pathological for a lot to die suddenly. */ continue; } else if (remaining_children_to_start) { /* we hit a 1 second timeout in which none of the previous * generation of children needed to be reaped... so assume * they're all done, and pick up the slack if any is left. */ remaining_children_to_start = \ startup_children(remaining_children_to_start); /* In any event we really shouldn't do the code below because * few of the servers we just started are in the IDLE state * yet, so we'd mistakenly create an extra server. */ continue; } perform_child_maintenance(); } } int ap_mpm_run(apr_pool_t *_pconf, apr_pool_t *plog, server_rec *s) { int remaining_children_to_start; int i; apr_status_t rv; apr_size_t one = 1; ap_listen_rec *lr; apr_socket_t *sock = NULL; int fd; ap_log_pid(pconf, ap_pid_fname); first_server_limit = server_limit; first_thread_limit = thread_limit; if (changed_limit_at_restart) { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, "WARNING: Attempt to change ServerLimit or ThreadLimit " "ignored during restart"); changed_limit_at_restart = 0; } ap_server_conf = s; if ((ap_accept_lock_mech == APR_LOCK_SYSVSEM) || (ap_accept_lock_mech == APR_LOCK_POSIXSEM)) { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, s, "Server configured for an accept lock mechanism that " "cannot be used with perchild. Falling back to FCNTL."); ap_accept_lock_mech = APR_LOCK_FCNTL; } /* Initialize cross-process accept lock */ ap_lock_fname = apr_psprintf(_pconf, "%s.%u", ap_server_root_relative(_pconf, ap_lock_fname), my_pid); rv = SAFE_ACCEPT(apr_proc_mutex_create(&process_accept_mutex, ap_lock_fname, ap_accept_lock_mech, _pconf)); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_EMERG, rv, s, "Couldn't create cross-process lock"); return 1; } if (!is_graceful) { if (ap_run_pre_mpm(s->process->pool, SB_SHARED) != OK) { return 1; } } /* Initialize the child table */ if (!is_graceful) { for (i = 0; i < server_limit; i++) { ap_child_table[i].pid = 0; } } /* We need to put the new listeners at the end of the ap_listeners * list. If we don't, then the pool will be cleared before the * open_logs phase is called for the second time, and ap_listeners * will have only invalid data. If that happens, then the sockets * that we opened using make_sock() will be lost, and the server * won't start. */ for (lr = ap_listeners ; lr->next != NULL; lr = lr->next) { continue; } apr_os_file_get(&fd, pipe_of_death_in); apr_os_sock_put(&sock, &fd, pconf); lr->next = apr_palloc(pconf, sizeof(*lr)); lr->next->sd = sock; lr->next->active = 1; lr->next->accept_func = check_pipe_of_death; lr->next->next = NULL; lr = lr->next; num_listensocks++; set_signals(); /* If we're doing a graceful_restart then we're going to see a lot * of children exiting immediately when we get into the main loop * below (because we just sent them AP_SIG_GRACEFUL). This happens * pretty rapidly... and for each one that exits we'll start a new one * until we reach at least daemons_min_free. But we may be permitted to * start more than that, so we'll just keep track of how many we're * supposed to start up without the 1 second penalty between each fork. */ remaining_children_to_start = num_daemons; if (!is_graceful) { remaining_children_to_start = \ startup_children(remaining_children_to_start); } else { /* give the system some time to recover before kicking into * exponential mode */ hold_off_on_exponential_spawning = 10; } ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, "%s configured -- resuming normal operations", ap_get_server_version()); ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf, "Server built: %s", ap_get_server_built()); #ifdef AP_MPM_WANT_SET_ACCEPT_LOCK_MECH ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "AcceptMutex: %s (default: %s)", apr_proc_mutex_name(process_accept_mutex), apr_proc_mutex_defname()); #endif restart_pending = shutdown_pending = 0; server_main_loop(remaining_children_to_start); if (shutdown_pending) { /* Time to gracefully shut down: * Kill child processes, tell them to call child_exit, etc... */ if (unixd_killpg(getpgrp(), SIGTERM) < 0) { ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM"); } ap_reclaim_child_processes(1); /* Start with SIGTERM */ if (!child_fatal) { /* cleanup pid file on normal shutdown */ const char *pidfile = NULL; pidfile = ap_server_root_relative (pconf, ap_pid_fname); if (pidfile != NULL && unlink(pidfile) == 0) { ap_log_error(APLOG_MARK, APLOG_INFO, 0, ap_server_conf, "removed PID file %s (pid=%ld)", pidfile, (long)getpid()); } ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, "caught SIGTERM, shutting down"); } return 1; } /* we've been told to restart */ apr_signal(SIGHUP, SIG_IGN); if (one_process) { /* not worth thinking about */ return 1; } if (is_graceful) { char char_of_death = '!'; ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, AP_SIG_GRACEFUL_STRING " received. " "Doing graceful restart"); /* This is mostly for debugging... so that we know what is still * gracefully dealing with existing request. */ for (i = 0; i < num_daemons; ++i) { if (ap_child_table[i].pid) { ap_child_table[i].status = SERVER_DYING; } } /* give the children the signal to die */ for (i = 0; i < num_daemons;) { if ((rv = apr_file_write(pipe_of_death_out, &char_of_death, &one)) != APR_SUCCESS) { if (APR_STATUS_IS_EINTR(rv)) continue; ap_log_error(APLOG_MARK, APLOG_WARNING, rv, ap_server_conf, "write pipe_of_death"); } i++; } } else { /* Kill 'em all. Since the child acts the same on the parents SIGTERM * and a SIGHUP, we may as well use the same signal, because some user * pthreads are stealing signals from us left and right. */ if (unixd_killpg(getpgrp(), SIGTERM) < 0) { ap_log_error(APLOG_MARK, APLOG_WARNING, errno, ap_server_conf, "killpg SIGTERM"); } ap_reclaim_child_processes(1); /* Start with SIGTERM */ ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, ap_server_conf, "SIGHUP received. Attempting to restart"); } return 0; } /* This really should be a post_config hook, but the error log is already * redirected by that point, so we need to do this in the open_logs phase. */ static int perchild_open_logs(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { apr_status_t rv; pconf = p; ap_server_conf = s; if ((num_listensocks = ap_setup_listeners(ap_server_conf)) < 1) { ap_log_error(APLOG_MARK, APLOG_ALERT|APLOG_STARTUP, 0, NULL, "no listening sockets available, shutting down"); return DONE; } ap_log_pid(pconf, ap_pid_fname); if ((rv = ap_mpm_pod_open(pconf, &pod))) { ap_log_error(APLOG_MARK, APLOG_CRIT|APLOG_STARTUP, rv, NULL, "Could not open pipe-of-death."); return DONE; } if ((rv = apr_file_pipe_create(&pipe_of_death_in, &pipe_of_death_out, pconf)) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, (const server_rec*) ap_server_conf, "apr_file_pipe_create (pipe_of_death)"); exit(1); } if ((rv = apr_file_pipe_timeout_set(pipe_of_death_in, 0)) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_ERR, rv, (const server_rec*) ap_server_conf, "apr_file_pipe_timeout_set (pipe_of_death)"); exit(1); } return OK; } static int perchild_pre_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp) { static int restart_num = 0; int no_detach, debug, foreground; ap_directive_t *pdir; int i; int tmp_server_limit = DEFAULT_SERVER_LIMIT; int tmp_thread_limit = DEFAULT_THREAD_LIMIT; apr_status_t rv; debug = ap_exists_config_define("DEBUG"); if (debug) { foreground = one_process = 1; no_detach = 0; } else { one_process = ap_exists_config_define("ONE_PROCESS"); no_detach = ap_exists_config_define("NO_DETACH"); foreground = ap_exists_config_define("FOREGROUND"); } /* sigh, want this only the second time around */ if (restart_num++ == 1) { is_graceful = 0; if (!one_process && !foreground) { rv = apr_proc_detach(no_detach ? APR_PROC_DETACH_FOREGROUND : APR_PROC_DETACH_DAEMONIZE); if (rv != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, "apr_proc_detach failed"); return HTTP_INTERNAL_SERVER_ERROR; } } my_pid = getpid(); } unixd_pre_config(ptemp); ap_listen_pre_config(); num_daemons = DEFAULT_NUM_DAEMON; threads_to_start = DEFAULT_START_THREAD; min_spare_threads = DEFAULT_MIN_SPARE_THREAD; max_spare_threads = DEFAULT_MAX_SPARE_THREAD; max_threads = thread_limit; ap_pid_fname = DEFAULT_PIDLOG; ap_lock_fname = DEFAULT_LOCKFILE; ap_max_requests_per_child = DEFAULT_MAX_REQUESTS_PER_CHILD; curr_child_num = 0; #ifdef AP_MPM_WANT_SET_MAX_MEM_FREE ap_max_mem_free = APR_ALLOCATOR_MAX_FREE_UNLIMITED; #endif apr_cpystrn(ap_coredump_dir, ap_server_root, sizeof(ap_coredump_dir)); /* we need to know ServerLimit and ThreadLimit before we start processing * the tree because we need to already have allocated child_info_table */ for (pdir = ap_conftree; pdir != NULL; pdir = pdir->next) { if (!strcasecmp(pdir->directive, "ServerLimit")) { if (atoi(pdir->args) > tmp_server_limit) { tmp_server_limit = atoi(pdir->args); if (tmp_server_limit > MAX_SERVER_LIMIT) { tmp_server_limit = MAX_SERVER_LIMIT; } } } else if (!strcasecmp(pdir->directive, "ThreadLimit")) { if (atoi(pdir->args) > tmp_thread_limit) { tmp_thread_limit = atoi(pdir->args); if (tmp_thread_limit > MAX_THREAD_LIMIT) { tmp_thread_limit = MAX_THREAD_LIMIT; } } } } child_info_table = (child_info_t *)apr_pcalloc(p, tmp_server_limit * sizeof(child_info_t)); for (i = 0; i < tmp_server_limit; i++) { child_info_table[i].uid = -1; child_info_table[i].gid = -1; child_info_table[i].input = -1; child_info_table[i].output = -1; } return OK; } static int pass_request(request_rec *r) { int rv; apr_socket_t *thesock = ap_get_module_config(r->connection->conn_config, &core_module); struct msghdr msg; struct cmsghdr *cmsg; int sfd; struct iovec iov[2]; conn_rec *c = r->connection; apr_bucket_brigade *bb = apr_brigade_create(r->pool, c->bucket_alloc); apr_bucket_brigade *sockbb; char request_body[HUGE_STRING_LEN] = "\0"; apr_size_t l = sizeof(request_body); perchild_header h; apr_bucket *sockbuck; perchild_server_conf *sconf = (perchild_server_conf *) ap_get_module_config(r->server->module_config, &mpm_perchild_module); ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "passing request to another child. Vhost: %s, child %d %d", apr_table_get(r->headers_in, "Host"), child_num, sconf->output); ap_get_brigade(r->connection->input_filters, bb, AP_MODE_EXHAUSTIVE, APR_NONBLOCK_READ, 0); for (sockbuck = APR_BRIGADE_FIRST(bb); sockbuck != APR_BRIGADE_SENTINEL(bb); sockbuck = APR_BUCKET_NEXT(sockbuck)) { if (APR_BUCKET_IS_SOCKET(sockbuck)) { break; } } if (!sockbuck) { } sockbb = apr_brigade_split(bb, sockbuck); if (apr_brigade_flatten(bb, request_body, &l) != APR_SUCCESS) { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Unable to flatten brigade, declining request"); return DECLINED; } apr_os_sock_get(&sfd, thesock); h.p = r->pool; h.headers = apr_pstrcat(h.p, r->the_request, CRLF, "Host: ", r->hostname, CRLF, NULL); apr_table_do((int (*) (void *, const char *, const char *)) perchild_header_field, (void *) &h, r->headers_in, NULL); h.headers = apr_pstrcat(h.p, h.headers, CRLF, NULL); iov[0].iov_base = h.headers; iov[0].iov_len = strlen(h.headers) + 1; iov[1].iov_base = request_body; iov[1].iov_len = l + 1; msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_iov = iov; msg.msg_iovlen = 2; cmsg = apr_palloc(r->pool, sizeof(*cmsg) + sizeof(sfd)); cmsg->cmsg_len = sizeof(*cmsg) + sizeof(sfd); cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; memcpy(CMSG_DATA(cmsg), &sfd, sizeof(sfd)); msg.msg_control = cmsg; msg.msg_controllen = cmsg->cmsg_len; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Writing message to %d, passing sd: %d", sconf->output, sfd); if ((rv = sendmsg(sconf->output, &msg, 0)) == -1) { apr_pool_destroy(r->pool); ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Writing message failed %d %d", rv, errno); return -1; } ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Writing message succeeded %d", rv); apr_pool_destroy(r->pool); return 1; } static char *make_perchild_socket(const char *fullsockname, int sd[2]) { socketpair(PF_UNIX, SOCK_STREAM, 0, sd); return NULL; } static int perchild_post_config(apr_pool_t *p, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s) { int i; server_rec *sr; perchild_server_conf *sconf; int def_sd[2]; def_sd[0] = -1; def_sd[1] = -1; for (sr = s; sr; sr = sr->next) { sconf = (perchild_server_conf *)ap_get_module_config(sr->module_config, &mpm_perchild_module); if (sconf->input == -1) { sconf->fullsockname = apr_pstrcat(sr->process->pool, sconf->sockname, ".DEFAULT", NULL); if (def_sd[0] == -1) { if (!make_perchild_socket(sconf->fullsockname, def_sd)) { /* log error */ } } sconf->input = def_sd[0]; sconf->output = def_sd[1]; } } for (i = 0; i < num_daemons; i++) { if (child_info_table[i].uid == -1) { child_info_table[i].input = def_sd[0]; child_info_table[i].output = def_sd[1]; } } thread_socket_table = (int *)apr_pcalloc(p, thread_limit * sizeof(int)); for (i = 0; i < thread_limit; i++) { thread_socket_table[i] = AP_PERCHILD_THISCHILD; } ap_child_table = (ap_ctable *)apr_pcalloc(p, server_limit * sizeof(ap_ctable)); return OK; } static int perchild_post_read(request_rec *r) { int thread_num = r->connection->id % thread_limit; perchild_server_conf *sconf = (perchild_server_conf *) ap_get_module_config(r->server->module_config, &mpm_perchild_module); if (thread_socket_table[thread_num] != AP_PERCHILD_THISCHILD) { apr_socket_t *csd = NULL; apr_os_sock_put(&csd, &thread_socket_table[thread_num], r->connection->pool); ap_sock_disable_nagle(csd); ap_set_module_config(r->connection->conn_config, &core_module, csd); return OK; } else { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Determining if request should be passed. " "Child Num: %d, SD: %d, sd from table: %d, hostname from server: %s", child_num, sconf->input, child_info_table[child_num].input, r->server->server_hostname); /* sconf is the server config for this vhost, so if our socket * is not the same that was set in the config, then the request * needs to be passed to another child. */ if (sconf->input != child_info_table[child_num].input) { ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, ap_server_conf, "Passing request."); if (pass_request(r) == -1) { ap_log_error(APLOG_MARK, APLOG_ERR, 0, ap_server_conf, "Could not pass request to proper " "child, request will not be honored."); } longjmp(jmpbuffer, 1); } return OK; } return OK; } static void perchild_hooks(apr_pool_t *p) { /* The perchild open_logs phase must run before the core's, or stderr * will be redirected to a file, and the messages won't print to the * console. */ static const char *const aszSucc[] = {"core.c", NULL}; one_process = 0; ap_hook_open_logs(perchild_open_logs, NULL, aszSucc, APR_HOOK_MIDDLE); ap_hook_pre_config(perchild_pre_config, NULL, NULL, APR_HOOK_MIDDLE); ap_hook_post_config(perchild_post_config, NULL, NULL, APR_HOOK_MIDDLE); /* Both of these must be run absolutely first. If this request isn't for * this server then we need to forward it to the proper child. No sense * tying up this server running more post_read request hooks if it is * just going to be forwarded along. The process_connection hook allows * perchild to receive the passed request correctly, by automatically * filling in the core_input_filter's ctx pointer. */ ap_hook_post_read_request(perchild_post_read, NULL, NULL, APR_HOOK_REALLY_FIRST); ap_hook_process_connection(perchild_process_connection, NULL, NULL, APR_HOOK_REALLY_FIRST); } static const char *set_num_daemons(cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } num_daemons = atoi(arg); if (num_daemons > server_limit) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: NumServers of %d exceeds ServerLimit value " "of %d servers,", num_daemons, server_limit); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " lowering NumServers to %d. To increase, please " "see the", server_limit); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " ServerLimit directive."); num_daemons = server_limit; } else if (num_daemons < 1) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: Require NumServers > 0, setting to 1"); num_daemons = 1; } return NULL; } static const char *set_threads_to_start(cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } threads_to_start = atoi(arg); if (threads_to_start > thread_limit) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: StartThreads of %d exceeds ThreadLimit value" " of %d threads,", threads_to_start, thread_limit); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " lowering StartThreads to %d. To increase, please" " see the", thread_limit); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " ThreadLimit directive."); } else if (threads_to_start < 1) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: Require StartThreads > 0, setting to 1"); threads_to_start = 1; } return NULL; } static const char *set_min_spare_threads(cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } min_spare_threads = atoi(arg); if (min_spare_threads <= 0) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: detected MinSpareThreads set to non-positive."); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "Resetting to 1 to avoid almost certain Apache failure."); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "Please read the documentation."); min_spare_threads = 1; } return NULL; } static const char *set_max_spare_threads(cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } max_spare_threads = atoi(arg); if (max_spare_threads >= thread_limit) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: detected MinSpareThreads set higher than"); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "ThreadLimit. Resetting to %d", thread_limit); max_spare_threads = thread_limit; } return NULL; } static const char *set_max_threads(cmd_parms *cmd, void *dummy, const char *arg) { const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } max_threads = atoi(arg); if (max_threads > thread_limit) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: detected MaxThreadsPerChild set higher than"); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "ThreadLimit. Resetting to %d", thread_limit); max_threads = thread_limit; } return NULL; } static const char *set_child_per_uid(cmd_parms *cmd, void *dummy, const char *u, const char *g, const char *num) { int i; int max_this_time = atoi(num) + curr_child_num; for (i = curr_child_num; i < max_this_time; i++, curr_child_num++) { if (i > num_daemons) { return "Trying to use more child ID's than NumServers. Increase " "NumServers in your config file."; } child_info_table[i].uid = ap_uname2id(u); child_info_table[i].gid = ap_gname2id(g); #ifndef BIG_SECURITY_HOLE if (child_info_table[i].uid == 0 || child_info_table[i].gid == 0) { return "Assigning root user/group to a child."; } #endif } return NULL; } static const char *assign_childuid(cmd_parms *cmd, void *dummy, const char *uid, const char *gid) { int i; int matching = 0; int u = ap_uname2id(uid); int g = ap_gname2id(gid); const char *errstr; int socks[2]; perchild_server_conf *sconf = (perchild_server_conf *) ap_get_module_config(cmd->server->module_config, &mpm_perchild_module); sconf->fullsockname = apr_pstrcat(cmd->pool, sconf->sockname, ".", uid, ":", gid, NULL); if ((errstr = make_perchild_socket(sconf->fullsockname, socks))) { return errstr; } sconf->input = socks[0]; sconf->output = socks[1]; for (i = 0; i < num_daemons; i++) { if (u == child_info_table[i].uid && g == child_info_table[i].gid) { child_info_table[i].input = sconf->input; child_info_table[i].output = sconf->output; matching++; ap_log_error(APLOG_MARK, APLOG_DEBUG, 0, cmd->server, "filling out child_info_table; UID: %d, GID: %d, " "SD: %d %d, OUTPUT: %d %d, Child Num: %d", child_info_table[i].uid, child_info_table[i].gid, sconf->input, child_info_table[i].input, sconf->output, child_info_table[i].output, i); } } if (!matching) { return "Unable to find process with matching uid/gid."; } return NULL; } static const char *set_server_limit (cmd_parms *cmd, void *dummy, const char *arg) { int tmp_server_limit; const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } tmp_server_limit = atoi(arg); /* you cannot change ServerLimit across a restart; ignore * any such attempts */ if (first_server_limit && tmp_server_limit != server_limit) { /* how do we log a message? the error log is a bit bucket at this * point; we'll just have to set a flag so that ap_mpm_run() * logs a warning later */ changed_limit_at_restart = 1; return NULL; } server_limit = tmp_server_limit; if (server_limit > MAX_SERVER_LIMIT) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: ServerLimit of %d exceeds compile time limit " "of %d servers,", server_limit, MAX_SERVER_LIMIT); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " lowering ServerLimit to %d.", MAX_SERVER_LIMIT); server_limit = MAX_SERVER_LIMIT; } else if (server_limit < 1) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: Require ServerLimit > 0, setting to 1"); server_limit = 1; } return NULL; } static const char *set_thread_limit (cmd_parms *cmd, void *dummy, const char *arg) { int tmp_thread_limit; const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY); if (err != NULL) { return err; } tmp_thread_limit = atoi(arg); /* you cannot change ThreadLimit across a restart; ignore * any such attempts */ if (first_thread_limit && tmp_thread_limit != thread_limit) { /* how do we log a message? the error log is a bit bucket at this * point; we'll just have to set a flag so that ap_mpm_run() * logs a warning later */ changed_limit_at_restart = 1; return NULL; } thread_limit = tmp_thread_limit; if (thread_limit > MAX_THREAD_LIMIT) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: ThreadLimit of %d exceeds compile time limit " "of %d servers,", thread_limit, MAX_THREAD_LIMIT); ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, " lowering ThreadLimit to %d.", MAX_THREAD_LIMIT); thread_limit = MAX_THREAD_LIMIT; } else if (thread_limit < 1) { ap_log_error(APLOG_MARK, APLOG_STARTUP, 0, NULL, "WARNING: Require ThreadLimit > 0, setting to 1"); thread_limit = 1; } return NULL; } static const command_rec perchild_cmds[] = { UNIX_DAEMON_COMMANDS, LISTEN_COMMANDS, AP_INIT_TAKE1("NumServers", set_num_daemons, NULL, RSRC_CONF, "Number of children alive at the same time"), AP_INIT_TAKE1("StartThreads", set_threads_to_start, NULL, RSRC_CONF, "Number of threads each child creates"), AP_INIT_TAKE1("MinSpareThreads", set_min_spare_threads, NULL, RSRC_CONF, "Minimum number of idle threads per child, to handle " "request spikes"), AP_INIT_TAKE1("MaxSpareThreads", set_max_spare_threads, NULL, RSRC_CONF, "Maximum number of idle threads per child"), AP_INIT_TAKE1("MaxThreadsPerChild", set_max_threads, NULL, RSRC_CONF, "Maximum number of threads per child"), AP_INIT_TAKE3("ChildperUserID", set_child_per_uid, NULL, RSRC_CONF, "Specify a User and Group for a specific child process."), AP_INIT_TAKE2("AssignUserID", assign_childuid, NULL, RSRC_CONF, "Tie a virtual host to a specific child process."), AP_INIT_TAKE1("ServerLimit", set_server_limit, NULL, RSRC_CONF, "Maximum value of NumServers for this run of Apache"), AP_INIT_TAKE1("ThreadLimit", set_thread_limit, NULL, RSRC_CONF, "Maximum worker threads in a server for this run of Apache"), { NULL } }; static void *perchild_create_config(apr_pool_t *p, server_rec *s) { perchild_server_conf *c = (perchild_server_conf *) apr_pcalloc(p, sizeof(perchild_server_conf)); c->input = -1; c->output = -1; return c; } module AP_MODULE_DECLARE_DATA mpm_perchild_module = { MPM20_MODULE_STUFF, ap_mpm_rewrite_args, /* hook to run before apache parses args */ NULL, /* create per-directory config structure */ NULL, /* merge per-directory config structures */ perchild_create_config, /* create per-server config structure */ NULL, /* merge per-server config structures */ perchild_cmds, /* command apr_table_t */ perchild_hooks /* register_hooks */ };