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|
/*++
/* NAME
/* postqueue 1
/* SUMMARY
/* Postfix queue control
/* SYNOPSIS
/* \fBpostqueue\fR [\fB-c \fIconfig_dir\fR] \fB-f\fR
/* .br
/* \fBpostqueue\fR [\fB-c \fIconfig_dir\fR] \fB-p\fR
/* .br
/* \fBpostqueue\fR [\fB-c \fIconfig_dir\fR] \fB-s \fIsite\fR
/* DESCRIPTION
/* The \fBpostqueue\fR program implements the Postfix user interface
/* for queue management. It implements operations that are
/* traditionally available via the \fBsendmail\fR(1) command.
/* See the \fBpostsuper\fR(1) command for queue operations
/* that require super-user privileges such as deleting a message
/* from the queue or changing the status of a message.
/*
/* The following options are recognized:
/* .IP "\fB-c \fIconfig_dir\fR"
/* The \fBmain.cf\fR configuration file is in the named directory
/* instead of the default configuration directory. See also the
/* MAIL_CONFIG environment setting below.
/* .IP \fB-f\fR
/* Flush the queue: attempt to deliver all queued mail.
/*
/* This option implements the traditional \fBsendmail -q\fR command,
/* by contacting the Postfix \fBqmgr\fR(8) daemon.
/* .IP \fB-p\fR
/* Produce a traditional sendmail-style queue listing.
/* This option implements the traditional \fBmailq\fR command,
/* by contacting the Postfix \fBshowq\fR(8) daemon.
/*
/* Each queue entry shows the queue file ID, message
/* size, arrival time, sender, and the recipients that still need to
/* be delivered. If mail could not be delivered upon the last attempt,
/* the reason for failure is shown. This mode of operation is implemented
/* by executing the \fBpostqueue\fR(1) command. The queue ID string
/* is followed by an optional status character:
/* .RS
/* .IP \fB*\fR
/* The message is in the \fBactive\fR queue, i.e. the message is
/* selected for delivery.
/* .IP \fB!\fR
/* The message is in the \fBhold\fR queue, i.e. no further delivery
/* attempt will be made until the mail is taken off hold.
/* .RE
/* .IP "\fB-s \fIsite\fR"
/* Schedule immediate delivery of all mail that is queued for the named
/* \fIsite\fR. The site must be eligible for the "fast flush" service.
/* See \fBflush\fR(8) for more information about the "fast flush"
/* service.
/*
/* This option implements the traditional \fBsendmail -qR\fIsite\fR
/* command, by contacting the Postfix \fBflush\fR(8) daemon.
/* .IP \fB-v\fR
/* Enable verbose logging for debugging purposes. Multiple \fB-v\fR
/* options make the software increasingly verbose.
/* SECURITY
/* .ad
/* .fi
/* This program is designed to run with set-group ID privileges, so
/* that it can connect to Postfix daemon processes.
/* DIAGNOSTICS
/* Problems are logged to \fBsyslogd\fR(8) and to the standard error
/* stream.
/* ENVIRONMENT
/* .ad
/* .fi
/* .IP MAIL_CONFIG
/* Directory with the \fBmain.cf\fR file.
/*
/* In order to avoid exploitation of set-group ID privileges, it is not
/* possible to specify arbitrary directory names.
/*
/* A non-standard directory is allowed only if the name is listed in the
/* standard \fBmain.cf\fR file, in the \fBalternate_config_directories\fR
/* configuration parameter value.
/*
/* Only the superuser is allowed to specify arbitrary directory names.
/* FILES
/* /var/spool/postfix, mail queue
/* /etc/postfix, configuration files
/* CONFIGURATION PARAMETERS
/* .ad
/* .fi
/* .IP \fBimport_environment\fR
/* List of names of environment parameters that can be imported
/* from non-Postfix processes.
/* .IP \fBqueue_directory\fR
/* Top-level directory of the Postfix queue. This is also the root
/* directory of Postfix daemons that run chrooted.
/* .IP \fBfast_flush_domains\fR
/* List of domains that will receive "fast flush" service (default: all
/* domains that this system is willing to relay mail to). This list
/* specifies the domains that Postfix accepts in the SMTP \fBETRN\fR
/* request and in the \fBsendmail -qR\fR command.
/* SEE ALSO
/* sendmail(1) sendmail-compatible user interface
/* postsuper(1) privileged queue operations
/* qmgr(8) queue manager
/* showq(8) list mail queue
/* flush(8) fast flush service
/* 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
/*--*/
/* System library. */
#include <sys_defs.h>
#include <sys/stat.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>
#include <sysexits.h>
#include <errno.h>
/* Utility library. */
#include <msg.h>
#include <mymalloc.h>
#include <clean_env.h>
#include <vstream.h>
#include <msg_vstream.h>
#include <msg_syslog.h>
#include <argv.h>
#include <safe.h>
#include <connect.h>
#include <valid_hostname.h>
/* Global library. */
#include <mail_proto.h>
#include <mail_params.h>
#include <mail_conf.h>
#include <mail_task.h>
#include <debug_process.h>
#include <mail_run.h>
#include <mail_flush.h>
#include <flush_clnt.h>
#include <smtp_stream.h>
/* Application-specific. */
/*
* WARNING WARNING WARNING
*
* This software is designed to run set-gid. In order to avoid exploitation of
* privilege, this software should not run any external commands, nor should
* it take any information from the user, unless that information can be
* properly sanitized. To get an idea of how much information a process can
* inherit from a potentially hostile user, examine all the members of the
* process structure (typically, in /usr/include/sys/proc.h): the current
* directory, open files, timers, signals, environment, command line, umask,
* and so on.
*/
/*
* Modes of operation.
*/
#define PQ_MODE_DEFAULT 0 /* noop */
#define PQ_MODE_MAILQ_LIST 1 /* list mail queue */
#define PQ_MODE_FLUSH_QUEUE 2 /* flush queue */
#define PQ_MODE_FLUSH_SITE 3 /* flush site */
/*
* Silly little macros (SLMs).
*/
#define STR vstring_str
/* show_queue - show queue status */
static void show_queue(void)
{
char buf[VSTREAM_BUFSIZE];
VSTREAM *showq;
int n;
/*
* Connect to the show queue service. Terminate silently when piping into
* a program that terminates early.
*/
if ((showq = mail_connect(MAIL_CLASS_PUBLIC, var_showq_service, BLOCKING)) != 0) {
while ((n = vstream_fread(showq, buf, sizeof(buf))) > 0) {
if (vstream_fwrite(VSTREAM_OUT, buf, n) != n
|| vstream_fflush(VSTREAM_OUT) != 0) {
if (errno == EPIPE)
break;
msg_fatal("write error: %m");
}
}
if (vstream_fclose(showq) && errno != EPIPE)
msg_warn("close: %m");
}
/*
* Don't assume that the mail system is down when the user has
* insufficient permission to access the showq socket.
*/
else if (errno == EACCES) {
msg_fatal_status(EX_SOFTWARE,
"Connect to the %s %s service: %m",
var_mail_name, var_showq_service);
}
/*
* When the mail system is down, the superuser can still access the queue
* directly. Just run the showq program in stand-alone mode.
*/
else if (geteuid() == 0) {
ARGV *argv;
int stat;
msg_warn("Mail system is down -- accessing queue directly");
argv = argv_alloc(6);
argv_add(argv, var_showq_service, "-u", "-S", (char *) 0);
for (n = 0; n < msg_verbose; n++)
argv_add(argv, "-v", (char *) 0);
argv_terminate(argv);
stat = mail_run_foreground(var_daemon_dir, argv->argv);
argv_free(argv);
}
/*
* When the mail system is down, unprivileged users are stuck, because by
* design the mail system contains no set_uid programs. The only way for
* an unprivileged user to cross protection boundaries is to talk to the
* showq daemon.
*/
else {
msg_fatal_status(EX_UNAVAILABLE,
"Queue report unavailable - mail system is down");
}
}
/* flush_queue - force delivery */
static void flush_queue(void)
{
/*
* Trigger the flush queue service.
*/
if (mail_flush_deferred() < 0)
msg_fatal_status(EX_UNAVAILABLE,
"Cannot flush mail queue - mail system is down");
if (mail_flush_maildrop() < 0)
msg_fatal_status(EX_UNAVAILABLE,
"Cannot flush mail queue - mail system is down");
}
/* flush_site - flush mail for site */
static void flush_site(const char *site)
{
int status;
switch (status = flush_send(site)) {
case FLUSH_STAT_OK:
exit(0);
case FLUSH_STAT_BAD:
msg_fatal_status(EX_USAGE, "Invalid request: \"%s\"", site);
case FLUSH_STAT_FAIL:
msg_fatal_status(EX_UNAVAILABLE,
"Cannot flush mail queue - mail system is down");
case FLUSH_STAT_DENY:
msg_fatal_status(EX_UNAVAILABLE,
"Flush service is not configured for destination \"%s\"",
site);
default:
msg_fatal_status(EX_SOFTWARE,
"Unknown flush server reply status %d", status);
}
}
/* usage - scream and die */
static NORETURN usage(void)
{
msg_fatal_status(EX_USAGE, "usage: postqueue -f | postqueue -p | postqueue -s site");
}
/* main - the main program */
int main(int argc, char **argv)
{
struct stat st;
char *slash;
int c;
int fd;
int mode = PQ_MODE_DEFAULT;
char *site_to_flush = 0;
ARGV *import_env;
char *last;
int bad_site;
/*
* Be consistent with file permissions.
*/
umask(022);
/*
* To minimize confusion, make sure that the standard file descriptors
* are open before opening anything else. XXX Work around for 44BSD where
* fstat can return EBADF on an open file descriptor.
*/
for (fd = 0; fd < 3; fd++)
if (fstat(fd, &st) == -1
&& (close(fd), open("/dev/null", O_RDWR, 0)) != fd)
msg_fatal_status(EX_UNAVAILABLE, "open /dev/null: %m");
/*
* Initialize. Set up logging, read the global configuration file and
* extract configuration information. Set up signal handlers so that we
* can clean up incomplete output.
*/
if ((slash = strrchr(argv[0], '/')) != 0)
argv[0] = slash + 1;
msg_vstream_init(argv[0], VSTREAM_ERR);
msg_syslog_init(mail_task("postqueue"), LOG_PID, LOG_FACILITY);
set_mail_conf_str(VAR_PROCNAME, var_procname = mystrdup(argv[0]));
/*
* Parse JCL. This program is set-gid and must sanitize all command-line
* parameters. The configuration directory argument is validated by the
* mail configuration read routine. Don't do complex things until we have
* completed initializations.
*/
while ((c = GETOPT(argc, argv, "c:fps:v")) > 0) {
switch (c) {
case 'c': /* non-default configuration */
if (setenv(CONF_ENV_PATH, optarg, 1) < 0)
msg_fatal_status(EX_UNAVAILABLE, "out of memory");
break;
case 'f': /* flush queue */
if (mode != PQ_MODE_DEFAULT)
usage();
mode = PQ_MODE_FLUSH_QUEUE;
break;
case 'p': /* traditional mailq */
if (mode != PQ_MODE_DEFAULT)
usage();
mode = PQ_MODE_MAILQ_LIST;
break;
case 's': /* flush site */
if (mode != PQ_MODE_DEFAULT)
usage();
mode = PQ_MODE_FLUSH_SITE;
site_to_flush = optarg;
break;
case 'v':
msg_verbose++;
break;
default:
usage();
}
}
if (argc > optind)
usage();
/*
* Further initialization...
*/
mail_conf_read();
/*
* This program is designed to be set-gid, which makes it a potential
* target for attack. If not running as root, strip the environment so we
* don't have to trust the C library. If running as root, don't strip the
* environment so that showq can receive non-default configuration
* directory info when the mail system is down.
*/
if (geteuid() != 0) {
import_env = argv_split(var_import_environ, ", \t\r\n");
clean_env(import_env->argv);
argv_free(import_env);
}
if (chdir(var_queue_dir))
msg_fatal_status(EX_UNAVAILABLE, "chdir %s: %m", var_queue_dir);
signal(SIGPIPE, SIG_IGN);
/* End of initializations. */
/*
* Further input validation.
*/
if (site_to_flush != 0) {
bad_site = 0;
if (*site_to_flush == '['
&& *(last = site_to_flush + strlen(site_to_flush) - 1) == ']') {
*last = 0;
bad_site = !valid_hostaddr(site_to_flush + 1, DONT_GRIPE);
*last = ']';
} else {
bad_site = (!valid_hostname(site_to_flush, DONT_GRIPE)
&& !valid_hostaddr(site_to_flush, DONT_GRIPE));
}
if (bad_site)
msg_fatal_status(EX_USAGE,
"Cannot flush mail queue - invalid destination: \"%.100s%s\"",
site_to_flush, strlen(site_to_flush) > 100 ? "..." : "");
}
/*
* Start processing.
*/
switch (mode) {
default:
msg_panic("unknown operation mode: %d", mode);
/* NOTREACHED */
case PQ_MODE_MAILQ_LIST:
show_queue();
exit(0);
break;
case PQ_MODE_FLUSH_SITE:
flush_site(site_to_flush);
exit(0);
break;
case PQ_MODE_FLUSH_QUEUE:
flush_queue();
exit(0);
break;
case PQ_MODE_DEFAULT:
usage();
/* NOTREACHED */
}
}
|