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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
commitb5896ba9f6047e7031e2bdee0622d543e11a6734 (patch)
treefd7b460593a2fee1be579bec5697e6d887ea3421 /src/flush/flush.c
parentInitial commit. (diff)
downloadpostfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.tar.xz
postfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.zip
Adding upstream version 3.4.23.upstream/3.4.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/flush/flush.c')
-rw-r--r--src/flush/flush.c857
1 files changed, 857 insertions, 0 deletions
diff --git a/src/flush/flush.c b/src/flush/flush.c
new file mode 100644
index 0000000..2e261bc
--- /dev/null
+++ b/src/flush/flush.c
@@ -0,0 +1,857 @@
+/*++
+/* NAME
+/* flush 8
+/* SUMMARY
+/* Postfix fast flush server
+/* SYNOPSIS
+/* \fBflush\fR [generic Postfix daemon options]
+/* DESCRIPTION
+/* The \fBflush\fR(8) server maintains a record of deferred
+/* mail by destination.
+/* This information is used to improve the performance of the SMTP
+/* \fBETRN\fR request, and of its command-line equivalent,
+/* "\fBsendmail -qR\fR" or "\fBpostqueue -f\fR".
+/* This program expects to be run from the \fBmaster\fR(8) process
+/* manager.
+/*
+/* The record is implemented as a per-destination logfile with
+/* as contents the queue IDs of deferred mail. A logfile is
+/* append-only, and is truncated when delivery is requested
+/* for the corresponding destination. A destination is the
+/* part on the right-hand side of the right-most \fB@\fR in
+/* an email address.
+/*
+/* Per-destination logfiles of deferred mail are maintained only for
+/* eligible destinations. The list of eligible destinations is
+/* specified with the \fBfast_flush_domains\fR configuration parameter,
+/* which defaults to \fB$relay_domains\fR.
+/*
+/* This server implements the following requests:
+/* .IP "\fBadd\fI sitename queueid\fR"
+/* Inform the \fBflush\fR(8) server that the message with the specified
+/* queue ID is queued for the specified destination.
+/* .IP "\fBsend_site\fI sitename\fR"
+/* Request delivery of mail that is queued for the specified
+/* destination.
+/* .IP "\fBsend_file\fI queueid\fR"
+/* Request delivery of the specified deferred message.
+/* .IP \fBrefresh\fR
+/* Refresh non-empty per-destination logfiles that were not read in
+/* \fB$fast_flush_refresh_time\fR hours, by simulating
+/* send requests (see above) for the corresponding destinations.
+/* .sp
+/* Delete empty per-destination logfiles that were not updated in
+/* \fB$fast_flush_purge_time\fR days.
+/* .sp
+/* This request completes in the background.
+/* .IP \fBpurge\fR
+/* Do a \fBrefresh\fR for all per-destination logfiles.
+/* SECURITY
+/* .ad
+/* .fi
+/* The \fBflush\fR(8) server is not security-sensitive. It does not
+/* talk to the network, and it does not talk to local users.
+/* The fast flush server can run chrooted at fixed low privilege.
+/* DIAGNOSTICS
+/* Problems and transactions are logged to \fBsyslogd\fR(8)
+/* or \fBpostlogd\fR(8).
+/* BUGS
+/* Fast flush logfiles are truncated only after a "send"
+/* request, not when mail is actually delivered, and therefore can
+/* accumulate outdated or redundant data. In order to maintain sanity,
+/* "refresh" must be executed periodically. This can
+/* be automated with a suitable wakeup timer setting in the
+/* \fBmaster.cf\fR configuration file.
+/*
+/* Upon receipt of a request to deliver mail for an eligible
+/* destination, the \fBflush\fR(8) server requests delivery of all messages
+/* that are listed in that destination's logfile, regardless of the
+/* recipients of those messages. This is not an issue for mail
+/* that is sent to a \fBrelay_domains\fR destination because
+/* such mail typically only has recipients in one domain.
+/* CONFIGURATION PARAMETERS
+/* .ad
+/* .fi
+/* Changes to \fBmain.cf\fR are picked up automatically as \fBflush\fR(8)
+/* processes run for only a limited amount of time. Use the command
+/* "\fBpostfix reload\fR" to speed up a change.
+/*
+/* The text below provides only a parameter summary. See
+/* \fBpostconf\fR(5) for more details including examples.
+/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
+/* The default location of the Postfix main.cf and master.cf
+/* configuration files.
+/* .IP "\fBdaemon_timeout (18000s)\fR"
+/* How much time a Postfix daemon process may take to handle a
+/* request before it is terminated by a built-in watchdog timer.
+/* .IP "\fBfast_flush_domains ($relay_domains)\fR"
+/* Optional list of destinations that are eligible for per-destination
+/* logfiles with mail that is queued to those destinations.
+/* .IP "\fBfast_flush_refresh_time (12h)\fR"
+/* The time after which a non-empty but unread per-destination "fast
+/* flush" logfile needs to be refreshed.
+/* .IP "\fBfast_flush_purge_time (7d)\fR"
+/* The time after which an empty per-destination "fast flush" logfile
+/* is deleted.
+/* .IP "\fBipc_timeout (3600s)\fR"
+/* The time limit for sending or receiving information over an internal
+/* communication channel.
+/* .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 "\fBparent_domain_matches_subdomains (see 'postconf -d' output)\fR"
+/* A list of Postfix features where the pattern "example.com" also
+/* matches subdomains of example.com,
+/* instead of requiring an explicit ".example.com" pattern.
+/* .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
+/* /var/spool/postfix/flush, "fast flush" logfiles.
+/* SEE ALSO
+/* smtpd(8), SMTP server
+/* qmgr(8), queue manager
+/* postconf(5), configuration parameters
+/* master(5), generic daemon options
+/* master(8), process manager
+/* postlogd(8), Postfix logging
+/* syslogd(8), system logging
+/* README FILES
+/* .ad
+/* .fi
+/* Use "\fBpostconf readme_directory\fR" or
+/* "\fBpostconf html_directory\fR" to locate this information.
+/* .na
+/* .nf
+/* ETRN_README, Postfix ETRN howto
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* HISTORY
+/* This service was introduced with Postfix version 1.0.
+/* 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 library. */
+
+#include <sys_defs.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <utime.h>
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <events.h>
+#include <vstream.h>
+#include <vstring.h>
+#include <vstring_vstream.h>
+#include <myflock.h>
+#include <htable.h>
+#include <dict.h>
+#include <scan_dir.h>
+#include <stringops.h>
+#include <safe_open.h>
+#include <warn_stat.h>
+#include <midna_domain.h>
+
+/* Global library. */
+
+#include <mail_params.h>
+#include <mail_version.h>
+#include <mail_queue.h>
+#include <mail_proto.h>
+#include <mail_flush.h>
+#include <flush_clnt.h>
+#include <mail_conf.h>
+#include <mail_scan_dir.h>
+#include <maps.h>
+#include <domain_list.h>
+#include <match_parent_style.h>
+
+/* Single server skeleton. */
+
+#include <mail_server.h>
+
+/* Application-specific. */
+
+ /*
+ * Tunable parameters. The fast_flush_domains parameter is not defined here,
+ * because it is also used by the global library, and therefore is owned by
+ * the library.
+ */
+int var_fflush_refresh;
+int var_fflush_purge;
+
+ /*
+ * Flush policy stuff.
+ */
+static DOMAIN_LIST *flush_domains;
+
+ /*
+ * Some hard-wired policy: how many queue IDs we remember while we're
+ * flushing a logfile (duplicate elimination). Sites with 1000+ emails
+ * queued should arrange for permanent connectivity.
+ */
+#define FLUSH_DUP_FILTER_SIZE 10000 /* graceful degradation */
+
+ /*
+ * Silly little macros.
+ */
+#define STR(x) vstring_str(x)
+#define STREQ(x,y) ((x) == (y) || strcmp(x,y) == 0)
+
+ /*
+ * Forward declarations resulting from breaking up routines according to
+ * name space: domain names versus safe-to-use pathnames.
+ */
+static int flush_add_path(const char *, const char *);
+static int flush_send_path(const char *, int);
+
+ /*
+ * Do we only refresh the per-destination logfile, or do we really request
+ * mail delivery as if someone sent ETRN? If the latter, we must override
+ * information about unavailable hosts or unavailable transports.
+ *
+ * When selectively flushing deferred mail, we need to override the queue
+ * manager's "dead destination" information and unthrottle transports and
+ * queues. There are two options:
+ *
+ * - Unthrottle all transports and queues before we move mail to the incoming
+ * queue. This is less accurate, but has the advantage when flushing lots of
+ * mail, because Postfix can skip delivery of flushed messages after it
+ * discovers that a destination is (still) unavailable.
+ *
+ * - Unthrottle some transports and queues after the queue manager moves mail
+ * to the active queue. This is more accurate, but has the disadvantage when
+ * flushing lots of mail, because Postfix cannot skip delivery of flushed
+ * messages after it discovers that a destination is (still) unavailable.
+ */
+#define REFRESH_ONLY 0
+#define UNTHROTTLE_BEFORE (1<<0)
+#define UNTHROTTLE_AFTER (1<<1)
+
+/* flush_site_to_path - convert domain or [addr] to harmless string */
+
+static VSTRING *flush_site_to_path(VSTRING *path, const char *site)
+{
+ const char *ptr;
+ int ch;
+
+ /*
+ * Convert the name to ASCII, so that we don't to end up with non-ASCII
+ * names in the file system. The IDNA library functions fold case.
+ */
+#ifndef NO_EAI
+ if ((site = midna_domain_to_ascii(site)) == 0)
+ return (0);
+#endif
+
+ /*
+ * Allocate buffer on the fly; caller still needs to clean up.
+ */
+ if (path == 0)
+ path = vstring_alloc(10);
+
+ /*
+ * Mask characters that could upset the name-to-queue-file mapping code.
+ */
+ for (ptr = site; (ch = *(unsigned const char *) ptr) != 0; ptr++)
+ if (ISALNUM(ch))
+ VSTRING_ADDCH(path, tolower(ch));
+ else
+ VSTRING_ADDCH(path, '_');
+ VSTRING_TERMINATE(path);
+
+ if (msg_verbose)
+ msg_info("site %s to path %s", site, STR(path));
+
+ return (path);
+}
+
+/* flush_add_service - append queue ID to per-site fast flush logfile */
+
+static int flush_add_service(const char *site, const char *queue_id)
+{
+ const char *myname = "flush_add_service";
+ VSTRING *site_path;
+ int status;
+
+ if (msg_verbose)
+ msg_info("%s: site %s queue_id %s", myname, site, queue_id);
+
+ /*
+ * If this site is not eligible for logging, deny the request.
+ */
+ if (domain_list_match(flush_domains, site) == 0)
+ return (flush_domains->error ? FLUSH_STAT_FAIL : FLUSH_STAT_DENY);
+
+ /*
+ * Map site to path and update log.
+ */
+ if ((site_path = flush_site_to_path((VSTRING *) 0, site)) == 0)
+ return (FLUSH_STAT_DENY);
+ status = flush_add_path(STR(site_path), queue_id);
+ vstring_free(site_path);
+
+ return (status);
+}
+
+/* flush_add_path - add record to log */
+
+static int flush_add_path(const char *path, const char *queue_id)
+{
+ const char *myname = "flush_add_path";
+ VSTREAM *log;
+
+ /*
+ * Sanity check.
+ */
+ if (!mail_queue_id_ok(path))
+ return (FLUSH_STAT_BAD);
+
+ /*
+ * Open the logfile or bust.
+ */
+ if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path,
+ O_CREAT | O_APPEND | O_WRONLY, 0600)) == 0)
+ msg_fatal("%s: open fast flush logfile %s: %m", myname, path);
+
+ /*
+ * We must lock the logfile, so that we don't lose information due to
+ * concurrent access. If the lock takes too long, the Postfix watchdog
+ * will eventually take care of the problem, but it will take a while.
+ */
+ if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0)
+ msg_fatal("%s: lock fast flush logfile %s: %m", myname, path);
+
+ /*
+ * Append the queue ID. With 15 bits of microsecond time, a queue ID is
+ * not recycled often enough for false hits to be a problem. If it does,
+ * then we could add other signature information, such as the file size
+ * in bytes.
+ */
+ vstream_fprintf(log, "%s\n", queue_id);
+ if (vstream_fflush(log))
+ msg_warn("write fast flush logfile %s: %m", path);
+
+ /*
+ * Clean up.
+ */
+ if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0)
+ msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path);
+ if (vstream_fclose(log) != 0)
+ msg_warn("write fast flush logfile %s: %m", path);
+
+ return (FLUSH_STAT_OK);
+}
+
+/* flush_send_service - flush mail queued for site */
+
+static int flush_send_service(const char *site, int how)
+{
+ const char *myname = "flush_send_service";
+ VSTRING *site_path;
+ int status;
+
+ if (msg_verbose)
+ msg_info("%s: site %s", myname, site);
+
+ /*
+ * If this site is not eligible for logging, deny the request.
+ */
+ if (domain_list_match(flush_domains, site) == 0)
+ return (flush_domains->error ? FLUSH_STAT_FAIL : FLUSH_STAT_DENY);
+
+ /*
+ * Map site name to path name and flush the log.
+ */
+ if ((site_path = flush_site_to_path((VSTRING *) 0, site)) == 0)
+ return (FLUSH_STAT_DENY);
+ status = flush_send_path(STR(site_path), how);
+ vstring_free(site_path);
+
+ return (status);
+}
+
+/* flush_one_file - move one queue file to incoming queue */
+
+static int flush_one_file(const char *queue_id, VSTRING *queue_file,
+ struct utimbuf * tbuf, int how)
+{
+ const char *myname = "flush_one_file";
+ const char *queue_name;
+ const char *path;
+
+ /*
+ * Some other instance of this program may flush some logfile and may
+ * just have moved this queue file to the incoming queue.
+ */
+ for (queue_name = MAIL_QUEUE_DEFERRED; /* see below */ ;
+ queue_name = MAIL_QUEUE_INCOMING) {
+ path = mail_queue_path(queue_file, queue_name, queue_id);
+ if (utime(path, tbuf) == 0)
+ break;
+ if (errno != ENOENT)
+ msg_warn("%s: update %s time stamps: %m", myname, path);
+ if (STREQ(queue_name, MAIL_QUEUE_INCOMING))
+ return (0);
+ }
+
+ /*
+ * With the UNTHROTTLE_AFTER strategy, we leave it up to the queue
+ * manager to unthrottle transports and queues as it reads recipients
+ * from a queue file. We request this unthrottle operation by setting the
+ * group read permission bit.
+ *
+ * Note: we must avoid using chmod(). It is not only slower than fchmod()
+ * but it is also less secure. With chmod(), an attacker could repeatedly
+ * send requests to the flush server and trick it into changing
+ * permissions of non-queue files, by exploiting a race condition.
+ *
+ * We use safe_open() because we don't validate the file content before
+ * modifying the file status.
+ */
+ if (how & UNTHROTTLE_AFTER) {
+ VSTRING *why;
+ struct stat st;
+ VSTREAM *fp;
+
+ for (why = vstring_alloc(1); /* see below */ ;
+ queue_name = MAIL_QUEUE_INCOMING,
+ path = mail_queue_path(queue_file, queue_name, queue_id)) {
+ if ((fp = safe_open(path, O_RDWR, 0, &st, -1, -1, why)) != 0)
+ break;
+ if (errno != ENOENT)
+ msg_warn("%s: open %s: %s", myname, path, STR(why));
+ if (errno != ENOENT || STREQ(queue_name, MAIL_QUEUE_INCOMING)) {
+ vstring_free(why);
+ return (0);
+ }
+ }
+ vstring_free(why);
+ if ((st.st_mode & MAIL_QUEUE_STAT_READY) != MAIL_QUEUE_STAT_READY) {
+ (void) vstream_fclose(fp);
+ return (0);
+ }
+ if (fchmod(vstream_fileno(fp), st.st_mode | MAIL_QUEUE_STAT_UNTHROTTLE) < 0)
+ msg_warn("%s: fchmod %s: %m", myname, path);
+ (void) vstream_fclose(fp);
+ }
+
+ /*
+ * Move the file to the incoming queue, if it isn't already there.
+ */
+ if (STREQ(queue_name, MAIL_QUEUE_INCOMING) == 0
+ && mail_queue_rename(queue_id, queue_name, MAIL_QUEUE_INCOMING) < 0
+ && errno != ENOENT)
+ msg_warn("%s: rename from %s to %s: %m",
+ path, queue_name, MAIL_QUEUE_INCOMING);
+
+ /*
+ * If we got here, we achieved something, so let's claim succes.
+ */
+ return (1);
+}
+
+/* flush_send_path - flush logfile file */
+
+static int flush_send_path(const char *path, int how)
+{
+ const char *myname = "flush_send_path";
+ VSTRING *queue_id;
+ VSTRING *queue_file;
+ VSTREAM *log;
+ struct utimbuf tbuf;
+ static char qmgr_flush_trigger[] = {
+ QMGR_REQ_FLUSH_DEAD, /* flush dead site/transport cache */
+ };
+ static char qmgr_scan_trigger[] = {
+ QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */
+ };
+ HTABLE *dup_filter;
+ int count;
+
+ /*
+ * Sanity check.
+ */
+ if (!mail_queue_id_ok(path))
+ return (FLUSH_STAT_BAD);
+
+ /*
+ * Open the logfile. If the file does not exist, then there is no queued
+ * mail for this destination.
+ */
+ if ((log = mail_queue_open(MAIL_QUEUE_FLUSH, path, O_RDWR, 0600)) == 0) {
+ if (errno != ENOENT)
+ msg_fatal("%s: open fast flush logfile %s: %m", myname, path);
+ return (FLUSH_STAT_OK);
+ }
+
+ /*
+ * We must lock the logfile, so that we don't lose information when it is
+ * truncated. Unfortunately, this means that the file can be locked for a
+ * significant amount of time. If things really get stuck the Postfix
+ * watchdog will take care of it.
+ */
+ if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_EXCLUSIVE) < 0)
+ msg_fatal("%s: lock fast flush logfile %s: %m", myname, path);
+
+ /*
+ * With the UNTHROTTLE_BEFORE strategy, we ask the queue manager to
+ * unthrottle all transports and queues before we move a deferred queue
+ * file to the incoming queue. This minimizes a race condition where the
+ * queue manager seizes a queue file before it knows that we want to
+ * flush that message.
+ *
+ * This reduces the race condition time window to a very small amount (the
+ * flush server does not really know when the queue manager reads its
+ * command fifo). But there is a worse race, where the queue manager
+ * moves a deferred queue file to the active queue before we have a
+ * chance to expedite its delivery.
+ */
+ if (how & UNTHROTTLE_BEFORE)
+ mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
+ qmgr_flush_trigger, sizeof(qmgr_flush_trigger));
+
+ /*
+ * This is the part that dominates running time: schedule the listed
+ * queue files for delivery by updating their file time stamps and by
+ * moving them from the deferred queue to the incoming queue. This should
+ * take no more than a couple seconds under normal conditions. Filter out
+ * duplicate queue file names to avoid hammering the file system, with
+ * some finite limit on the amount of memory that we are willing to
+ * sacrifice for duplicate filtering. Graceful degradation.
+ *
+ * By moving selected queue files from the deferred queue to the incoming
+ * queue we optimize for the case where most deferred mail is for other
+ * sites. If that assumption does not hold, i.e. all deferred mail is for
+ * the same site, then doing a "fast flush" will cost more disk I/O than
+ * a "slow flush" that delivers the entire deferred queue. This penalty
+ * is only temporary - it will go away after we unite the active queue
+ * and the incoming queue.
+ */
+ queue_id = vstring_alloc(10);
+ queue_file = vstring_alloc(10);
+ dup_filter = htable_create(10);
+ tbuf.actime = tbuf.modtime = event_time();
+ for (count = 0; vstring_get_nonl(queue_id, log) != VSTREAM_EOF; count++) {
+ if (!mail_queue_id_ok(STR(queue_id))) {
+ msg_warn("bad queue id \"%.30s...\" in fast flush logfile %s",
+ STR(queue_id), path);
+ continue;
+ }
+ if (dup_filter->used >= FLUSH_DUP_FILTER_SIZE
+ || htable_find(dup_filter, STR(queue_id)) == 0) {
+ if (msg_verbose)
+ msg_info("%s: logfile %s: update queue file %s time stamps",
+ myname, path, STR(queue_id));
+ if (dup_filter->used <= FLUSH_DUP_FILTER_SIZE)
+ htable_enter(dup_filter, STR(queue_id), 0);
+ count += flush_one_file(STR(queue_id), queue_file, &tbuf, how);
+ } else {
+ if (msg_verbose)
+ msg_info("%s: logfile %s: skip queue file %s as duplicate",
+ myname, path, STR(queue_file));
+ }
+ }
+ htable_free(dup_filter, (void (*) (void *)) 0);
+ vstring_free(queue_file);
+ vstring_free(queue_id);
+
+ /*
+ * Truncate the fast flush log.
+ */
+ if (count > 0 && ftruncate(vstream_fileno(log), (off_t) 0) < 0)
+ msg_fatal("%s: truncate fast flush logfile %s: %m", myname, path);
+
+ /*
+ * Workaround for noatime mounts. Use futimes() if available.
+ */
+ (void) utimes(VSTREAM_PATH(log), (struct timeval *) 0);
+
+ /*
+ * Request delivery and clean up.
+ */
+ if (myflock(vstream_fileno(log), INTERNAL_LOCK, MYFLOCK_OP_NONE) < 0)
+ msg_fatal("%s: unlock fast flush logfile %s: %m", myname, path);
+ if (vstream_fclose(log) != 0)
+ msg_warn("%s: read fast flush logfile %s: %m", myname, path);
+ if (count > 0) {
+ if (msg_verbose)
+ msg_info("%s: requesting delivery for logfile %s", myname, path);
+ mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
+ qmgr_scan_trigger, sizeof(qmgr_scan_trigger));
+ }
+ return (FLUSH_STAT_OK);
+}
+
+/* flush_send_file_service - flush one queue file */
+
+static int flush_send_file_service(const char *queue_id)
+{
+ const char *myname = "flush_send_file_service";
+ VSTRING *queue_file;
+ struct utimbuf tbuf;
+ static char qmgr_scan_trigger[] = {
+ QMGR_REQ_SCAN_INCOMING, /* scan incoming queue */
+ };
+
+ /*
+ * Sanity check.
+ */
+ if (!mail_queue_id_ok(queue_id))
+ return (FLUSH_STAT_BAD);
+
+ if (msg_verbose)
+ msg_info("%s: requesting delivery for queue_id %s", myname, queue_id);
+
+ queue_file = vstring_alloc(30);
+ tbuf.actime = tbuf.modtime = event_time();
+ if (flush_one_file(queue_id, queue_file, &tbuf, UNTHROTTLE_AFTER) > 0)
+ mail_trigger(MAIL_CLASS_PUBLIC, var_queue_service,
+ qmgr_scan_trigger, sizeof(qmgr_scan_trigger));
+ vstring_free(queue_file);
+
+ return (FLUSH_STAT_OK);
+}
+
+/* flush_refresh_service - refresh logfiles beyond some age */
+
+static int flush_refresh_service(int max_age)
+{
+ const char *myname = "flush_refresh_service";
+ SCAN_DIR *scan;
+ char *site_path;
+ struct stat st;
+ VSTRING *path = vstring_alloc(10);
+
+ scan = scan_dir_open(MAIL_QUEUE_FLUSH);
+ while ((site_path = mail_scan_dir_next(scan)) != 0) {
+ if (!mail_queue_id_ok(site_path))
+ continue; /* XXX grumble. */
+ mail_queue_path(path, MAIL_QUEUE_FLUSH, site_path);
+ if (stat(STR(path), &st) < 0) {
+ if (errno != ENOENT)
+ msg_warn("%s: stat %s: %m", myname, STR(path));
+ else if (msg_verbose)
+ msg_info("%s: %s: %m", myname, STR(path));
+ continue;
+ }
+ if (st.st_size == 0) {
+ if (st.st_mtime + var_fflush_purge < event_time()) {
+ if (unlink(STR(path)) < 0)
+ msg_warn("remove logfile %s: %m", STR(path));
+ else if (msg_verbose)
+ msg_info("%s: unlink %s, empty and unchanged for %d days",
+ myname, STR(path), var_fflush_purge / 86400);
+ } else if (msg_verbose)
+ msg_info("%s: skip logfile %s - empty log", myname, site_path);
+ } else if (st.st_atime + max_age < event_time()) {
+ if (msg_verbose)
+ msg_info("%s: flush logfile %s", myname, site_path);
+ flush_send_path(site_path, REFRESH_ONLY);
+ } else {
+ if (msg_verbose)
+ msg_info("%s: skip logfile %s, unread for <%d hours(s) ",
+ myname, site_path, max_age / 3600);
+ }
+ }
+ scan_dir_close(scan);
+ vstring_free(path);
+
+ return (FLUSH_STAT_OK);
+}
+
+/* flush_request_receive - receive request */
+
+static int flush_request_receive(VSTREAM *client_stream, VSTRING *request)
+{
+ int count;
+
+ /*
+ * Kluge: choose the protocol depending on the request size.
+ */
+ if (read_wait(vstream_fileno(client_stream), var_ipc_timeout) < 0) {
+ msg_warn("timeout while waiting for data from %s",
+ VSTREAM_PATH(client_stream));
+ return (-1);
+ }
+ if ((count = peekfd(vstream_fileno(client_stream))) < 0) {
+ msg_warn("cannot examine read buffer of %s: %m",
+ VSTREAM_PATH(client_stream));
+ return (-1);
+ }
+
+ /*
+ * Short request: master trigger. Use the string+null protocol.
+ */
+ if (count <= 2) {
+ if (vstring_get_null(request, client_stream) == VSTREAM_EOF) {
+ msg_warn("end-of-input while reading request from %s: %m",
+ VSTREAM_PATH(client_stream));
+ return (-1);
+ }
+ }
+
+ /*
+ * Long request: real flush client. Use the attribute list protocol.
+ */
+ else {
+ if (attr_scan(client_stream,
+ ATTR_FLAG_MORE | ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_REQ, request),
+ ATTR_TYPE_END) != 1) {
+ return (-1);
+ }
+ }
+ return (0);
+}
+
+/* flush_service - perform service for client */
+
+static void flush_service(VSTREAM *client_stream, char *unused_service,
+ char **argv)
+{
+ VSTRING *request = vstring_alloc(10);
+ VSTRING *site = 0;
+ VSTRING *queue_id = 0;
+ static char wakeup[] = { /* master wakeup request */
+ TRIGGER_REQ_WAKEUP,
+ 0,
+ };
+ int status = FLUSH_STAT_BAD;
+
+ /*
+ * Sanity check. This service takes no command-line arguments.
+ */
+ if (argv[0])
+ msg_fatal("unexpected command-line argument: %s", argv[0]);
+
+ /*
+ * This routine runs whenever a client connects to the UNIX-domain socket
+ * dedicated to the fast flush service. What we see below is a little
+ * protocol to (1) read a request from the client (the name of the site)
+ * and (2) acknowledge that we have received the request.
+ *
+ * All connection-management stuff is handled by the common code in
+ * single_server.c.
+ */
+ if (flush_request_receive(client_stream, request) == 0) {
+ if (STREQ(STR(request), FLUSH_REQ_ADD)) {
+ site = vstring_alloc(10);
+ queue_id = vstring_alloc(10);
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_SITE, site),
+ RECV_ATTR_STR(MAIL_ATTR_QUEUEID, queue_id),
+ ATTR_TYPE_END) == 2
+ && mail_queue_id_ok(STR(queue_id)))
+ status = flush_add_service(STR(site), STR(queue_id));
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, status),
+ ATTR_TYPE_END);
+ } else if (STREQ(STR(request), FLUSH_REQ_SEND_SITE)) {
+ site = vstring_alloc(10);
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_SITE, site),
+ ATTR_TYPE_END) == 1)
+ status = flush_send_service(STR(site), UNTHROTTLE_BEFORE);
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, status),
+ ATTR_TYPE_END);
+ } else if (STREQ(STR(request), FLUSH_REQ_SEND_FILE)) {
+ queue_id = vstring_alloc(10);
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_QUEUEID, queue_id),
+ ATTR_TYPE_END) == 1)
+ status = flush_send_file_service(STR(queue_id));
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, status),
+ ATTR_TYPE_END);
+ } else if (STREQ(STR(request), FLUSH_REQ_REFRESH)
+ || STREQ(STR(request), wakeup)) {
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, FLUSH_STAT_OK),
+ ATTR_TYPE_END);
+ vstream_fflush(client_stream);
+ (void) flush_refresh_service(var_fflush_refresh);
+ } else if (STREQ(STR(request), FLUSH_REQ_PURGE)) {
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, FLUSH_STAT_OK),
+ ATTR_TYPE_END);
+ vstream_fflush(client_stream);
+ (void) flush_refresh_service(0);
+ }
+ } else
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, status),
+ ATTR_TYPE_END);
+ vstring_free(request);
+ if (site)
+ vstring_free(site);
+ if (queue_id)
+ vstring_free(queue_id);
+}
+
+/* pre_jail_init - pre-jail initialization */
+
+static void pre_jail_init(char *unused_name, char **unused_argv)
+{
+ flush_domains = domain_list_init(VAR_FFLUSH_DOMAINS, MATCH_FLAG_RETURN
+ | match_parent_style(VAR_FFLUSH_DOMAINS),
+ var_fflush_domains);
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+/* main - pass control to the single-threaded skeleton */
+
+int main(int argc, char **argv)
+{
+ static const CONFIG_TIME_TABLE time_table[] = {
+ VAR_FFLUSH_REFRESH, DEF_FFLUSH_REFRESH, &var_fflush_refresh, 1, 0,
+ VAR_FFLUSH_PURGE, DEF_FFLUSH_PURGE, &var_fflush_purge, 1, 0,
+ 0,
+ };
+
+ /*
+ * Fingerprint executables and core dumps.
+ */
+ MAIL_VERSION_STAMP_ALLOCATE;
+
+ single_server_main(argc, argv, flush_service,
+ CA_MAIL_SERVER_TIME_TABLE(time_table),
+ CA_MAIL_SERVER_PRE_INIT(pre_jail_init),
+ CA_MAIL_SERVER_UNLIMITED,
+ 0);
+}