Adding upstream version 3.4.23.upstream/3.4.23upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 594 insertions, 0 deletions

diff --git a/src/master/master.c b/src/master/master.c
new file mode 100644
index 0000000..d901778
--- /dev/null
+++ b/src/master/master.c
@@ -0,0 +1,594 @@
+/*++
+/* NAME
+/*	master 8
+/* SUMMARY
+/*	Postfix master process
+/* SYNOPSIS
+/*	\fBmaster\fR [\fB-Dditvw\fR] [\fB-c \fIconfig_dir\fR] [\fB-e \fIexit_time\fR]
+/* DESCRIPTION
+/*	The \fBmaster\fR(8) daemon is the resident process that runs Postfix
+/*	daemons on demand: daemons to send or receive messages via the
+/*	network, daemons to deliver mail locally, etc.  These daemons are
+/*	created on demand up to a configurable maximum number per service.
+/*
+/*	Postfix daemons terminate voluntarily, either after being idle for
+/*	a configurable amount of time, or after having serviced a
+/*	configurable number of requests. Exceptions to this rule are the
+/*	resident queue manager, address verification server, and the TLS
+/*	session cache and pseudo-random number server.
+/*
+/*	The behavior of the \fBmaster\fR(8) daemon is controlled by the
+/*	\fBmaster.cf\fR configuration file, as described in \fBmaster\fR(5).
+/*
+/*	Options:
+/* .IP "\fB-c \fIconfig_dir\fR"
+/*	Read the \fBmain.cf\fR and \fBmaster.cf\fR configuration files in
+/*	the named directory instead of the default configuration directory.
+/*	This also overrides the configuration files for other Postfix
+/*	daemon processes.
+/* .IP \fB-D\fR
+/*	After initialization, run a debugger on the master process. The
+/*	debugging command is specified with the \fBdebugger_command\fR in
+/*	the \fBmain.cf\fR global configuration file.
+/* .IP \fB-d\fR
+/*	Do not redirect stdin, stdout or stderr to /dev/null, and
+/*	do not discard the controlling terminal. This must be used
+/*	for debugging only.
+/* .IP "\fB-e \fIexit_time\fR"
+/*	Terminate the master process after \fIexit_time\fR seconds. Child
+/*	processes terminate at their convenience.
+/* .IP \fB-i\fR
+/*	Enable \fBinit\fR mode: do not become a session or process
+/*	group leader; and similar to \fB-s\fR, do not redirect stdout
+/*	to /dev/null, so that "maillog_file = /dev/stdout" works.
+/*	This mode is allowed only if the process ID equals 1.
+/* .sp
+/*	This feature is available in Postfix 3.3 and later.
+/* .IP \fB-s\fR
+/*	Do not redirect stdout to /dev/null, so that "maillog_file
+/*	= /dev/stdout" works.
+/* .sp
+/*	This feature is available in Postfix 3.4 and later.
+/* .IP \fB-t\fR
+/*	Test mode. Return a zero exit status when the \fBmaster.pid\fR lock
+/*	file does not exist or when that file is not locked.  This is evidence
+/*	that the \fBmaster\fR(8) daemon is not running.
+/* .IP \fB-v\fR
+/*	Enable verbose logging for debugging purposes. This option
+/*	is passed on to child processes. Multiple \fB-v\fR options
+/*	make the software increasingly verbose.
+/* .IP \fB-w\fR
+/*	Wait in a dummy foreground process, while the real master
+/*	daemon initializes in a background process.  The dummy
+/*	foreground process returns a zero exit status only if the
+/*	master daemon initialization is successful, and if it
+/*	completes in a reasonable amount of time.
+/* .sp
+/*	This feature is available in Postfix 2.10 and later.
+/* .PP
+/*	Signals:
+/* .IP \fBSIGHUP\fR
+/*	Upon receipt of a \fBHUP\fR signal (e.g., after "\fBpostfix reload\fR"),
+/*	the master process re-reads its configuration files. If a service has
+/*	been removed from the \fBmaster.cf\fR file, its running processes
+/*	are terminated immediately.
+/*	Otherwise, running processes are allowed to terminate as soon
+/*	as is convenient, so that changes in configuration settings
+/*	affect only new service requests.
+/* .IP \fBSIGTERM\fR
+/*	Upon receipt of a \fBTERM\fR signal (e.g., after "\fBpostfix abort\fR"),
+/*	the master process passes the signal on to its child processes and
+/*	terminates.
+/*	This is useful for an emergency shutdown. Normally one would
+/*	terminate only the master ("\fBpostfix stop\fR") and allow running
+/*	processes to finish what they are doing.
+/* DIAGNOSTICS
+/*	Problems are reported to \fBsyslogd\fR(8) or \fBpostlogd\fR(8).
+/*	The exit status
+/*	is non-zero in case of problems, including problems while
+/*	initializing as a master daemon process in the background.
+/* ENVIRONMENT
+/* .ad
+/* .fi
+/* .IP \fBMAIL_DEBUG\fR
+/*	After initialization, start a debugger as specified with the
+/*	\fBdebugger_command\fR configuration parameter in the \fBmain.cf\fR
+/*	configuration file.
+/* .IP \fBMAIL_CONFIG\fR
+/*	Directory with Postfix configuration files.
+/* CONFIGURATION PARAMETERS
+/* .ad
+/* .fi
+/*	Unlike most Postfix daemon processes, the \fBmaster\fR(8) server does
+/*	not automatically pick up changes to \fBmain.cf\fR. Changes
+/*	to \fBmaster.cf\fR are never picked up automatically.
+/*	Use the "\fBpostfix reload\fR" command after a configuration change.
+/* RESOURCE AND RATE CONTROLS
+/* .ad
+/* .fi
+/* .IP "\fBdefault_process_limit (100)\fR"
+/*	The default maximal number of Postfix child processes that provide
+/*	a given service.
+/* .IP "\fBmax_idle (100s)\fR"
+/*	The maximum amount of time that an idle Postfix daemon process waits
+/*	for an incoming connection before terminating voluntarily.
+/* .IP "\fBmax_use (100)\fR"
+/*	The maximal number of incoming connections that a Postfix daemon
+/*	process will service before terminating voluntarily.
+/* .IP "\fBservice_throttle_time (60s)\fR"
+/*	How long the Postfix \fBmaster\fR(8) waits before forking a server that
+/*	appears to be malfunctioning.
+/* .PP
+/*	Available in Postfix version 2.6 and later:
+/* .IP "\fBmaster_service_disable (empty)\fR"
+/*	Selectively disable \fBmaster\fR(8) listener ports by service type
+/*	or by service name and type.
+/* MISCELLANEOUS CONTROLS
+/* .ad
+/* .fi
+/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
+/*	The default location of the Postfix main.cf and master.cf
+/*	configuration files.
+/* .IP "\fBdaemon_directory (see 'postconf -d' output)\fR"
+/*	The directory with Postfix support programs and daemon programs.
+/* .IP "\fBdebugger_command (empty)\fR"
+/*	The external command to execute when a Postfix daemon program is
+/*	invoked with the -D option.
+/* .IP "\fBinet_interfaces (all)\fR"
+/*	The network interface addresses that this mail system receives
+/*	mail on.
+/* .IP "\fBinet_protocols (all)\fR"
+/*	The Internet protocols Postfix will attempt to use when making
+/*	or accepting connections.
+/* .IP "\fBimport_environment (see 'postconf -d' output)\fR"
+/*	The list of environment parameters that a privileged Postfix
+/*	process will import from a non-Postfix parent process, or name=value
+/*	environment overrides.
+/* .IP "\fBmail_owner (postfix)\fR"
+/*	The UNIX system account that owns the Postfix queue and most Postfix
+/*	daemon processes.
+/* .IP "\fBprocess_id (read-only)\fR"
+/*	The process ID of a Postfix command or daemon process.
+/* .IP "\fBprocess_name (read-only)\fR"
+/*	The process name of a Postfix command or daemon process.
+/* .IP "\fBqueue_directory (see 'postconf -d' output)\fR"
+/*	The location of the Postfix top-level queue directory.
+/* .IP "\fBsyslog_facility (mail)\fR"
+/*	The syslog facility of Postfix logging.
+/* .IP "\fBsyslog_name (see 'postconf -d' output)\fR"
+/*	A prefix that is prepended to the process name in syslog
+/*	records, so that, for example, "smtpd" becomes "prefix/smtpd".
+/* .PP
+/*	Available in Postfix 3.3 and later:
+/* .IP "\fBservice_name (read-only)\fR"
+/*	The master.cf service name of a Postfix daemon process.
+/* FILES
+/* .ad
+/* .fi
+/*	To expand the directory names below into their actual values,
+/*	use the command "\fBpostconf config_directory\fR" etc.
+/* .na
+/* .nf
+/*
+/*	$config_directory/main.cf, global configuration file.
+/*	$config_directory/master.cf, master server configuration file.
+/*	$queue_directory/pid/master.pid, master lock file.
+/*	$data_directory/master.lock, master lock file.
+/* SEE ALSO
+/*	qmgr(8), queue manager
+/*	verify(8), address verification
+/*	master(5), master.cf configuration file syntax
+/*	postconf(5), main.cf configuration file syntax
+/*	postlogd(8), Postfix logging
+/*	syslogd(8), system logging
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Wietse Venema
+/*	Google, Inc.
+/*	111 8th Avenue
+/*	New York, NY 10011, USA
+/*--*/
+
+/* System libraries. */
+
+#include <sys_defs.h>
+#include <sys/stat.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <limits.h>
+
+/* Utility library. */
+
+#include <events.h>
+#include <msg.h>
+#include <vstring.h>
+#include <mymalloc.h>
+#include <iostuff.h>
+#include <vstream.h>
+#include <stringops.h>
+#include <myflock.h>
+#include <watchdog.h>
+#include <clean_env.h>
+#include <argv.h>
+#include <safe.h>
+#include <set_eugid.h>
+#include <set_ugid.h>
+
+/* Global library. */
+
+#include <mail_params.h>
+#include <mail_version.h>
+#include <debug_process.h>
+#include <mail_task.h>
+#include <mail_conf.h>
+#include <open_lock.h>
+#include <inet_proto.h>
+#include <mail_parm_split.h>
+#include <maillog_client.h>
+
+/* Application-specific. */
+
+#include "master.h"
+
+int     master_detach = 1;
+int     init_mode = 0;
+
+/* master_exit_event - exit for memory leak testing purposes */
+
+static void master_exit_event(int unused_event, void *unused_context)
+{
+    msg_info("master exit time has arrived");
+    exit(0);
+}
+
+/* usage - show hint and terminate */
+
+static NORETURN usage(const char *me)
+{
+    msg_fatal("usage: %s [-c config_dir] [-D (debug)] [-d (don't detach from terminal)] [-e exit_time] [-t (test)] [-v] [-w (wait for initialization)]", me);
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+/* main - main program */
+
+int     main(int argc, char **argv)
+{
+    static VSTREAM *lock_fp;
+    static VSTREAM *data_lock_fp;
+    VSTRING *lock_path;
+    VSTRING *data_lock_path;
+    off_t   inherited_limit;
+    int     debug_me = 0;
+    int     keep_stdout = 0;
+    int     ch;
+    int     fd;
+    int     n;
+    int     test_lock = 0;
+    VSTRING *why;
+    WATCHDOG *watchdog;
+    ARGV   *import_env;
+    int     wait_flag = 0;
+    int     monitor_fd = -1;
+
+    /*
+     * Fingerprint executables and core dumps.
+     */
+    MAIL_VERSION_STAMP_ALLOCATE;
+
+    /*
+     * Initialize.
+     */
+    umask(077);					/* never fails! */
+
+    /*
+     * Process environment options as early as we can.
+     */
+    if (getenv(CONF_ENV_VERB))
+	msg_verbose = 1;
+    if (getenv(CONF_ENV_DEBUG))
+	debug_me = 1;
+
+    /*
+     * Don't die when a process goes away unexpectedly.
+     */
+    signal(SIGPIPE, SIG_IGN);
+
+    /*
+     * Strip and save the process name for diagnostics etc.
+     */
+    var_procname = mystrdup(basename(argv[0]));
+
+    /*
+     * When running a child process, don't leak any open files that were
+     * leaked to us by our own (privileged) parent process. Descriptors 0-2
+     * are taken care of after we have initialized error logging.
+     * 
+     * Some systems such as AIX have a huge per-process open file limit. In
+     * those cases, limit the search for potential file descriptor leaks to
+     * just the first couple hundred.
+     * 
+     * The Debian post-installation script passes an open file descriptor into
+     * the master process and waits forever for someone to close it. Because
+     * of this we have to close descriptors > 2, and pray that doing so does
+     * not break things.
+     */
+    closefrom(3);
+
+    /*
+     * Initialize logging and exit handler.
+     */
+    maillog_client_init(mail_task(var_procname),
+			MAILLOG_CLIENT_FLAG_LOGWRITER_FALLBACK);
+
+    /*
+     * Check the Postfix library version as soon as we enable logging.
+     */
+    MAIL_VERSION_CHECK;
+
+    /*
+     * The mail system must be run by the superuser so it can revoke
+     * privileges for selected operations. That's right - it takes privileges
+     * to toss privileges.
+     */
+    if (getuid() != 0)
+	msg_fatal("the master command is reserved for the superuser");
+    if (unsafe() != 0)
+	msg_fatal("the master command must not run as a set-uid process");
+
+    /*
+     * Process JCL.
+     */
+    while ((ch = GETOPT(argc, argv, "c:Dde:istvw")) > 0) {
+	switch (ch) {
+	case 'c':
+	    if (setenv(CONF_ENV_PATH, optarg, 1) < 0)
+		msg_fatal("out of memory");
+	    break;
+	case 'd':
+	    master_detach = 0;
+	    break;
+	case 'e':
+	    event_request_timer(master_exit_event, (void *) 0, atoi(optarg));
+	    break;
+	case 'i':
+	    if (getpid() != 1)
+		msg_fatal("-i is allowed only for PID 1 process");
+	    init_mode = 1;
+	    keep_stdout = 1;
+	    break;
+	case 'D':
+	    debug_me = 1;
+	    break;
+	case 's':
+	    keep_stdout = 1;
+	    break;
+	case 't':
+	    test_lock = 1;
+	    break;
+	case 'v':
+	    msg_verbose++;
+	    break;
+	case 'w':
+	    wait_flag = 1;
+	    break;
+	default:
+	    usage(argv[0]);
+	    /* NOTREACHED */
+	}
+    }
+
+    /*
+     * This program takes no other arguments.
+     */
+    if (argc > optind)
+	usage(argv[0]);
+
+    /*
+     * Sanity check.
+     */
+    if (test_lock && wait_flag)
+	msg_fatal("the -t and -w options cannot be used together");
+    if (init_mode && (debug_me || !master_detach || wait_flag))
+	msg_fatal("the -i option cannot be used with -D, -d, or -w");
+
+    /*
+     * Run a foreground monitor process that returns an exit status of 0 when
+     * the child background process reports successful initialization as a
+     * daemon process. We use a generous limit in case main/master.cf specify
+     * symbolic hosts/ports and the naming service is slow.
+     */
+#define MASTER_INIT_TIMEOUT	100		/* keep this limit generous */
+
+    if (wait_flag)
+	monitor_fd = master_monitor(MASTER_INIT_TIMEOUT);
+
+    /*
+     * If started from a terminal, get rid of any tty association. This also
+     * means that all errors and warnings must go to the syslog daemon.
+     * Some new world has no terminals and prefers logging to stdout.
+     */
+    if (master_detach)
+	for (fd = 0; fd < 3; fd++) {
+	    if (fd == STDOUT_FILENO && keep_stdout)
+		continue;
+	    (void) close(fd);
+	    if (open("/dev/null", O_RDWR, 0) != fd)
+		msg_fatal("open /dev/null: %m");
+	}
+
+    /*
+     * Run in a separate process group, so that "postfix stop" can terminate
+     * all MTA processes cleanly. Give up if we can't separate from our
+     * parent process. We're not supposed to blow away the parent.
+     */
+    if (init_mode == 0 && debug_me == 0 && master_detach != 0
+	&& setsid() == -1 && getsid(0) != getpid())
+	msg_fatal("unable to set session and process group ID: %m");
+
+    /*
+     * Make some room for plumbing with file descriptors. XXX This breaks
+     * when a service listens on many ports. In order to do this right we
+     * must change the master-child interface so that descriptors do not need
+     * to have fixed numbers.
+     * 
+     * In a child we need two descriptors for the flow control pipe, one for
+     * child->master status updates and at least one for listening.
+     */
+    for (n = 0; n < 5; n++) {
+	if (close_on_exec(dup(0), CLOSE_ON_EXEC) < 0)
+	    msg_fatal("dup(0): %m");
+    }
+
+    /*
+     * Final initializations. Unfortunately, we must read the global Postfix
+     * configuration file after doing command-line processing, so that we get
+     * consistent results when we SIGHUP the server to reload configuration
+     * files.
+     */
+    master_vars_init();
+
+    /*
+     * In case of multi-protocol support. This needs to be done because
+     * master does not invoke mail_params_init() (it was written before that
+     * code existed).
+     */
+    (void) inet_proto_init(VAR_INET_PROTOCOLS, var_inet_protocols);
+
+    /*
+     * Environment import filter, to enforce consistent behavior whether
+     * Postfix is started by hand, or at system boot time.
+     */
+    import_env = mail_parm_split(VAR_IMPORT_ENVIRON, var_import_environ);
+    clean_env(import_env->argv);
+    argv_free(import_env);
+
+    if ((inherited_limit = get_file_limit()) < 0)
+	set_file_limit(OFF_T_MAX);
+
+    if (chdir(var_queue_dir))
+	msg_fatal("chdir %s: %m", var_queue_dir);
+
+    /*
+     * Lock down the master.pid file. In test mode, no file means that it
+     * isn't locked.
+     */
+    lock_path = vstring_alloc(10);
+    data_lock_path = vstring_alloc(10);
+    why = vstring_alloc(10);
+
+    vstring_sprintf(lock_path, "%s/%s.pid", DEF_PID_DIR, var_procname);
+    if (test_lock && access(vstring_str(lock_path), F_OK) < 0)
+	exit(0);
+    lock_fp = open_lock(vstring_str(lock_path), O_RDWR | O_CREAT, 0644, why);
+    if (test_lock)
+	exit(lock_fp ? 0 : 1);
+    if (lock_fp == 0)
+	msg_fatal("open lock file %s: %s",
+		  vstring_str(lock_path), vstring_str(why));
+    vstream_fprintf(lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4,
+		    (unsigned long) var_pid);
+    if (vstream_fflush(lock_fp))
+	msg_fatal("cannot update lock file %s: %m", vstring_str(lock_path));
+    close_on_exec(vstream_fileno(lock_fp), CLOSE_ON_EXEC);
+
+    /*
+     * Lock down the Postfix-writable data directory.
+     */
+    vstring_sprintf(data_lock_path, "%s/%s.lock", var_data_dir, var_procname);
+    set_eugid(var_owner_uid, var_owner_gid);
+    data_lock_fp =
+	open_lock(vstring_str(data_lock_path), O_RDWR | O_CREAT, 0644, why);
+    set_ugid(getuid(), getgid());
+    if (data_lock_fp == 0)
+	msg_fatal("open lock file %s: %s",
+		  vstring_str(data_lock_path), vstring_str(why));
+    vstream_fprintf(data_lock_fp, "%*lu\n", (int) sizeof(unsigned long) * 4,
+		    (unsigned long) var_pid);
+    if (vstream_fflush(data_lock_fp))
+	msg_fatal("cannot update lock file %s: %m", vstring_str(data_lock_path));
+    close_on_exec(vstream_fileno(data_lock_fp), CLOSE_ON_EXEC);
+
+    /*
+     * Clean up.
+     */
+    vstring_free(why);
+    vstring_free(lock_path);
+    vstring_free(data_lock_path);
+
+    /*
+     * Optionally start the debugger on ourself.
+     */
+    if (debug_me)
+	debug_process();
+
+    /*
+     * Finish initialization, last part. We must process configuration files
+     * after processing command-line parameters, so that we get consistent
+     * results when we SIGHUP the server to reload configuration files.
+     */
+    master_config();
+    master_sigsetup();
+    master_flow_init();
+    maillog_client_init(mail_task(var_procname),
+			MAILLOG_CLIENT_FLAG_LOGWRITER_FALLBACK);
+    msg_info("daemon started -- version %s, configuration %s",
+	     var_mail_version, var_config_dir);
+
+    /*
+     * Report successful initialization to the foreground monitor process.
+     */
+    if (monitor_fd >= 0) {
+	write(monitor_fd, "", 1);
+	(void) close(monitor_fd);
+    }
+
+    /*
+     * Process events. The event handler will execute the read/write/timer
+     * action routines. Whenever something has happened, see if we received
+     * any signal in the mean time. Although the master process appears to do
+     * multiple things at the same time, it really is all a single thread, so
+     * that there are no concurrency conflicts within the master process.
+     */
+#define MASTER_WATCHDOG_TIME	1000
+
+    watchdog = watchdog_create(MASTER_WATCHDOG_TIME, (WATCHDOG_FN) 0, (void *) 0);
+    for (;;) {
+#ifdef HAS_VOLATILE_LOCKS
+	if (myflock(vstream_fileno(lock_fp), INTERNAL_LOCK,
+		    MYFLOCK_OP_EXCLUSIVE) < 0)
+	    msg_fatal("refresh exclusive lock: %m");
+	if (myflock(vstream_fileno(data_lock_fp), INTERNAL_LOCK,
+		    MYFLOCK_OP_EXCLUSIVE) < 0)
+	    msg_fatal("refresh exclusive lock: %m");
+#endif
+	watchdog_start(watchdog);		/* same as trigger servers */
+	event_loop(MASTER_WATCHDOG_TIME / 2);
+	if (master_gotsighup) {
+	    msg_info("reload -- version %s, configuration %s",
+		     var_mail_version, var_config_dir);
+	    master_gotsighup = 0;		/* this first */
+	    master_vars_init();			/* then this */
+	    master_refresh();			/* then this */
+	    maillog_client_init(mail_task(var_procname),
+				MAILLOG_CLIENT_FLAG_LOGWRITER_FALLBACK);
+	}
+	if (master_gotsigchld) {
+	    if (msg_verbose)
+		msg_info("got sigchld");
+	    master_gotsigchld = 0;		/* this first */
+	    master_reap_child();		/* then this */
+	}
+    }
+}