Adding upstream version 3.4.23.upstream/3.4.23upstream

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

1 files changed, 570 insertions, 0 deletions

diff --git a/src/scache/scache.c b/src/scache/scache.c
new file mode 100644
index 0000000..d06cfca
--- /dev/null
+++ b/src/scache/scache.c
@@ -0,0 +1,570 @@
+/*++
+/* NAME
+/*	scache 8
+/* SUMMARY
+/*	Postfix shared connection cache server
+/* SYNOPSIS
+/*	\fBscache\fR [generic Postfix daemon options]
+/* DESCRIPTION
+/*	The \fBscache\fR(8) server maintains a shared multi-connection
+/*	cache. This information can be used by, for example, Postfix
+/*	SMTP clients or other Postfix delivery agents.
+/*
+/*	The connection cache is organized into logical destination
+/*	names, physical endpoint names, and connections.
+/*
+/*	As a specific example, logical SMTP destinations specify
+/*	(transport, domain, port), and physical SMTP endpoints
+/*	specify (transport, IP address, port).  An SMTP connection
+/*	may be saved after a successful mail transaction.
+/*
+/*	In the general case, one logical destination may refer to
+/*	zero or more physical endpoints, one physical endpoint may
+/*	be referenced by zero or more logical destinations, and
+/*	one endpoint may refer to zero or more connections.
+/*
+/*	The exact syntax of a logical destination or endpoint name
+/*	is application dependent; the \fBscache\fR(8) server does
+/*	not care.  A connection is stored as a file descriptor together
+/*	with application-dependent information that is needed to
+/*	re-activate a connection object. Again, the \fBscache\fR(8)
+/*	server is completely unaware of the details of that
+/*	information.
+/*
+/*	All information is stored with a finite time to live (ttl).
+/*	The connection cache daemon terminates when no client is
+/*	connected for \fBmax_idle\fR time units.
+/*
+/*	This server implements the following requests:
+/* .IP "\fBsave_endp\fI ttl endpoint endpoint_properties file_descriptor\fR"
+/*	Save the specified file descriptor and connection property data
+/*	under the specified endpoint name. The endpoint properties
+/*	are used by the client to re-activate a passivated connection
+/*	object.
+/* .IP "\fBfind_endp\fI endpoint\fR"
+/*	Look up cached properties and a cached file descriptor for the
+/*	specified endpoint.
+/* .IP "\fBsave_dest\fI ttl destination destination_properties endpoint\fR"
+/*	Save the binding between a logical destination and an
+/*	endpoint under the destination name, together with destination
+/*	specific connection properties. The destination properties
+/*	are used by the client to re-activate a passivated connection
+/*	object.
+/* .IP "\fBfind_dest\fI destination\fR"
+/*	Look up cached destination properties, cached endpoint properties,
+/*	and a cached file descriptor for the specified logical destination.
+/* SECURITY
+/* .ad
+/* .fi
+/*	The \fBscache\fR(8) server is not security-sensitive. It does not
+/*	talk to the network, and it does not talk to local users.
+/*	The \fBscache\fR(8) server can run chrooted at fixed low privilege.
+/*
+/*	The \fBscache\fR(8) server is not a trusted process. It must
+/*	not be used to store information that is security sensitive.
+/* DIAGNOSTICS
+/*	Problems and transactions are logged to \fBsyslogd\fR(8)
+/*	or \fBpostlogd\fR(8).
+/* BUGS
+/*	The session cache cannot be shared among multiple machines.
+/*
+/*	When a connection expires from the cache, it is closed without
+/*	the appropriate protocol specific handshake.
+/* CONFIGURATION PARAMETERS
+/* .ad
+/* .fi
+/*	Changes to \fBmain.cf\fR are picked up automatically as \fBscache\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.
+/* RESOURCE CONTROLS
+/* .ad
+/* .fi
+/* .IP "\fBconnection_cache_ttl_limit (2s)\fR"
+/*	The maximal time-to-live value that the \fBscache\fR(8) connection
+/*	cache server
+/*	allows.
+/* .IP "\fBconnection_cache_status_update_time (600s)\fR"
+/*	How frequently the \fBscache\fR(8) server logs usage statistics with
+/*	connection cache hit and miss rates for logical destinations and for
+/*	physical endpoints.
+/* 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_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 "\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 "\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 "\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.
+/* SEE ALSO
+/*	smtp(8), SMTP client
+/*	postconf(5), configuration parameters
+/*	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
+/*	CONNECTION_CACHE_README, Postfix connection cache
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* HISTORY
+/*	This service was introduced with Postfix version 2.2.
+/* 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 <time.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <iostuff.h>
+#include <htable.h>
+#include <ring.h>
+#include <events.h>
+
+/* Global library. */
+
+#include <mail_params.h>
+#include <mail_version.h>
+#include <mail_proto.h>
+#include <scache.h>
+
+/* Single server skeleton. */
+
+#include <mail_server.h>
+#include <mail_conf.h>
+
+/* Application-specific. */
+
+ /*
+  * Tunable parameters.
+  */
+int     var_scache_ttl_lim;
+int     var_scache_stat_time;
+
+ /*
+  * Request parameters.
+  */
+static VSTRING *scache_request;
+static VSTRING *scache_dest_label;
+static VSTRING *scache_dest_prop;
+static VSTRING *scache_endp_label;
+static VSTRING *scache_endp_prop;
+
+#ifdef CANT_WRITE_BEFORE_SENDING_FD
+static VSTRING *scache_dummy;
+
+#endif
+
+ /*
+  * Session cache instance.
+  */
+static SCACHE *scache;
+
+ /*
+  * Statistics.
+  */
+static int scache_dest_hits;
+static int scache_dest_miss;
+static int scache_dest_count;
+static int scache_endp_hits;
+static int scache_endp_miss;
+static int scache_endp_count;
+static int scache_sess_count;
+time_t  scache_start_time;
+
+ /*
+  * Silly little macros.
+  */
+#define STR(x)			vstring_str(x)
+#define VSTREQ(x,y)		(strcmp(STR(x),y) == 0)
+
+/* scache_save_endp_service - protocol to save endpoint->stream binding */
+
+static void scache_save_endp_service(VSTREAM *client_stream)
+{
+    const char *myname = "scache_save_endp_service";
+    int     ttl;
+    int     fd;
+    SCACHE_SIZE size;
+
+    if (attr_scan(client_stream,
+		  ATTR_FLAG_STRICT,
+		  RECV_ATTR_INT(MAIL_ATTR_TTL, &ttl),
+		  RECV_ATTR_STR(MAIL_ATTR_LABEL, scache_endp_label),
+		  RECV_ATTR_STR(MAIL_ATTR_PROP, scache_endp_prop),
+		  ATTR_TYPE_END) != 3
+	|| ttl <= 0) {
+	msg_warn("%s: bad or missing request parameter", myname);
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_BAD),
+		   ATTR_TYPE_END);
+	return;
+    } else if (
+#ifdef CANT_WRITE_BEFORE_SENDING_FD
+	       attr_print(client_stream, ATTR_FLAG_NONE,
+			  SEND_ATTR_STR(MAIL_ATTR_DUMMY, ""),
+			  ATTR_TYPE_END) != 0
+	       || vstream_fflush(client_stream) != 0
+	       || read_wait(vstream_fileno(client_stream),
+			    client_stream->timeout) < 0	/* XXX */
+	       ||
+#endif
+	       (fd = LOCAL_RECV_FD(vstream_fileno(client_stream))) < 0) {
+	msg_warn("%s: unable to receive file descriptor: %m", myname);
+	(void) attr_print(client_stream, ATTR_FLAG_NONE,
+			  SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_FAIL),
+			  ATTR_TYPE_END);
+	return;
+    } else {
+	scache_save_endp(scache,
+			 ttl > var_scache_ttl_lim ? var_scache_ttl_lim : ttl,
+			 STR(scache_endp_label), STR(scache_endp_prop), fd);
+	(void) attr_print(client_stream, ATTR_FLAG_NONE,
+			  SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_OK),
+			  ATTR_TYPE_END);
+	scache_size(scache, &size);
+	if (size.endp_count > scache_endp_count)
+	    scache_endp_count = size.endp_count;
+	if (size.sess_count > scache_sess_count)
+	    scache_sess_count = size.sess_count;
+	return;
+    }
+}
+
+/* scache_find_endp_service - protocol to find connection for endpoint */
+
+static void scache_find_endp_service(VSTREAM *client_stream)
+{
+    const char *myname = "scache_find_endp_service";
+    int     fd;
+
+    if (attr_scan(client_stream,
+		  ATTR_FLAG_STRICT,
+		  RECV_ATTR_STR(MAIL_ATTR_LABEL, scache_endp_label),
+		  ATTR_TYPE_END) != 1) {
+	msg_warn("%s: bad or missing request parameter", myname);
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_BAD),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   ATTR_TYPE_END);
+	return;
+    } else if ((fd = scache_find_endp(scache, STR(scache_endp_label),
+				      scache_endp_prop)) < 0) {
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_FAIL),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   ATTR_TYPE_END);
+	scache_endp_miss++;
+	return;
+    } else {
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_OK),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, STR(scache_endp_prop)),
+		   ATTR_TYPE_END);
+	if (vstream_fflush(client_stream) != 0
+#ifdef CANT_WRITE_BEFORE_SENDING_FD
+	    || attr_scan(client_stream, ATTR_FLAG_STRICT,
+			 RECV_ATTR_STR(MAIL_ATTR_DUMMY, scache_dummy),
+			 ATTR_TYPE_END) != 1
+#endif
+	    || LOCAL_SEND_FD(vstream_fileno(client_stream), fd) < 0
+#ifdef MUST_READ_AFTER_SENDING_FD
+	    || attr_scan(client_stream, ATTR_FLAG_STRICT,
+			 RECV_ATTR_STR(MAIL_ATTR_DUMMY, scache_dummy),
+			 ATTR_TYPE_END) != 1
+#endif
+	    )
+	    msg_warn("%s: cannot send file descriptor: %m", myname);
+	if (close(fd) < 0)
+	    msg_warn("close(%d): %m", fd);
+	scache_endp_hits++;
+	return;
+    }
+}
+
+/* scache_save_dest_service - protocol to save destination->endpoint binding */
+
+static void scache_save_dest_service(VSTREAM *client_stream)
+{
+    const char *myname = "scache_save_dest_service";
+    int     ttl;
+    SCACHE_SIZE size;
+
+    if (attr_scan(client_stream,
+		  ATTR_FLAG_STRICT,
+		  RECV_ATTR_INT(MAIL_ATTR_TTL, &ttl),
+		  RECV_ATTR_STR(MAIL_ATTR_LABEL, scache_dest_label),
+		  RECV_ATTR_STR(MAIL_ATTR_PROP, scache_dest_prop),
+		  RECV_ATTR_STR(MAIL_ATTR_LABEL, scache_endp_label),
+		  ATTR_TYPE_END) != 4
+	|| ttl <= 0) {
+	msg_warn("%s: bad or missing request parameter", myname);
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_BAD),
+		   ATTR_TYPE_END);
+	return;
+    } else {
+	scache_save_dest(scache,
+			 ttl > var_scache_ttl_lim ? var_scache_ttl_lim : ttl,
+			 STR(scache_dest_label), STR(scache_dest_prop),
+			 STR(scache_endp_label));
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_OK),
+		   ATTR_TYPE_END);
+	scache_size(scache, &size);
+	if (size.dest_count > scache_dest_count)
+	    scache_dest_count = size.dest_count;
+	if (size.endp_count > scache_endp_count)
+	    scache_endp_count = size.endp_count;
+	return;
+    }
+}
+
+/* scache_find_dest_service - protocol to find connection for destination */
+
+static void scache_find_dest_service(VSTREAM *client_stream)
+{
+    const char *myname = "scache_find_dest_service";
+    int     fd;
+
+    if (attr_scan(client_stream,
+		  ATTR_FLAG_STRICT,
+		  RECV_ATTR_STR(MAIL_ATTR_LABEL, scache_dest_label),
+		  ATTR_TYPE_END) != 1) {
+	msg_warn("%s: bad or missing request parameter", myname);
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_BAD),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   ATTR_TYPE_END);
+	return;
+    } else if ((fd = scache_find_dest(scache, STR(scache_dest_label),
+				      scache_dest_prop,
+				      scache_endp_prop)) < 0) {
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_FAIL),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, ""),
+		   ATTR_TYPE_END);
+	scache_dest_miss++;
+	return;
+    } else {
+	attr_print(client_stream, ATTR_FLAG_NONE,
+		   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_OK),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, STR(scache_dest_prop)),
+		   SEND_ATTR_STR(MAIL_ATTR_PROP, STR(scache_endp_prop)),
+		   ATTR_TYPE_END);
+	if (vstream_fflush(client_stream) != 0
+#ifdef CANT_WRITE_BEFORE_SENDING_FD
+	    || attr_scan(client_stream, ATTR_FLAG_STRICT,
+			 RECV_ATTR_STR(MAIL_ATTR_DUMMY, scache_dummy),
+			 ATTR_TYPE_END) != 1
+#endif
+	    || LOCAL_SEND_FD(vstream_fileno(client_stream), fd) < 0
+#ifdef MUST_READ_AFTER_SENDING_FD
+	    || attr_scan(client_stream, ATTR_FLAG_STRICT,
+			 RECV_ATTR_STR(MAIL_ATTR_DUMMY, scache_dummy),
+			 ATTR_TYPE_END) != 1
+#endif
+	    )
+	    msg_warn("%s: cannot send file descriptor: %m", myname);
+	if (close(fd) < 0)
+	    msg_warn("close(%d): %m", fd);
+	scache_dest_hits++;
+	return;
+    }
+}
+
+/* scache_service - perform service for client */
+
+static void scache_service(VSTREAM *client_stream, char *unused_service,
+			           char **argv)
+{
+
+    /*
+     * 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 scache service. All connection-management stuff is
+     * handled by the common code in multi_server.c.
+     * 
+     * XXX Workaround: with some requests, the client sends a dummy message
+     * after the server replies (yes that's a botch). When the scache server
+     * is slow, this dummy message may become concatenated with the next
+     * request from the same client. The do-while loop below will repeat
+     * instead of discarding the client request. We must process it now
+     * because there will be no select() notification.
+     */
+    do {
+	if (attr_scan(client_stream,
+		      ATTR_FLAG_MORE | ATTR_FLAG_STRICT,
+		      RECV_ATTR_STR(MAIL_ATTR_REQ, scache_request),
+		      ATTR_TYPE_END) == 1) {
+	    if (VSTREQ(scache_request, SCACHE_REQ_SAVE_DEST)) {
+		scache_save_dest_service(client_stream);
+	    } else if (VSTREQ(scache_request, SCACHE_REQ_FIND_DEST)) {
+		scache_find_dest_service(client_stream);
+	    } else if (VSTREQ(scache_request, SCACHE_REQ_SAVE_ENDP)) {
+		scache_save_endp_service(client_stream);
+	    } else if (VSTREQ(scache_request, SCACHE_REQ_FIND_ENDP)) {
+		scache_find_endp_service(client_stream);
+	    } else {
+		msg_warn("unrecognized request: \"%s\", ignored",
+			 STR(scache_request));
+		attr_print(client_stream, ATTR_FLAG_NONE,
+			   SEND_ATTR_INT(MAIL_ATTR_STATUS, SCACHE_STAT_BAD),
+			   ATTR_TYPE_END);
+	    }
+	}
+    } while (vstream_peek(client_stream) > 0);
+    vstream_fflush(client_stream);
+}
+
+/* scache_status_dump - log and reset cache statistics */
+
+static void scache_status_dump(char *unused_name, char **unused_argv)
+{
+    if (scache_dest_hits || scache_dest_miss
+	|| scache_endp_hits || scache_endp_miss
+	|| scache_dest_count || scache_endp_count
+	|| scache_sess_count)
+	msg_info("statistics: start interval %.15s",
+		 ctime(&scache_start_time) + 4);
+
+    if (scache_dest_hits || scache_dest_miss) {
+	msg_info("statistics: domain lookup hits=%d miss=%d success=%d%%",
+		 scache_dest_hits, scache_dest_miss,
+		 scache_dest_hits * 100
+		 / (scache_dest_hits + scache_dest_miss));
+	scache_dest_hits = scache_dest_miss = 0;
+    }
+    if (scache_endp_hits || scache_endp_miss) {
+	msg_info("statistics: address lookup hits=%d miss=%d success=%d%%",
+		 scache_endp_hits, scache_endp_miss,
+		 scache_endp_hits * 100
+		 / (scache_endp_hits + scache_endp_miss));
+	scache_endp_hits = scache_endp_miss = 0;
+    }
+    if (scache_dest_count || scache_endp_count || scache_sess_count) {
+	msg_info("statistics: max simultaneous domains=%d addresses=%d connection=%d",
+		 scache_dest_count, scache_endp_count, scache_sess_count);
+	scache_dest_count = 0;
+	scache_endp_count = 0;
+	scache_sess_count = 0;
+    }
+    scache_start_time = event_time();
+}
+
+/* scache_status_update - log and reset cache statistics periodically */
+
+static void scache_status_update(int unused_event, void *context)
+{
+    scache_status_dump((char *) 0, (char **) 0);
+    event_request_timer(scache_status_update, context, var_scache_stat_time);
+}
+
+/* post_jail_init - initialization after privilege drop */
+
+static void post_jail_init(char *unused_name, char **unused_argv)
+{
+
+    /*
+     * Pre-allocate the cache instance.
+     */
+    scache = scache_multi_create();
+
+    /*
+     * Pre-allocate buffers.
+     */
+    scache_request = vstring_alloc(10);
+    scache_dest_label = vstring_alloc(10);
+    scache_dest_prop = vstring_alloc(10);
+    scache_endp_label = vstring_alloc(10);
+    scache_endp_prop = vstring_alloc(10);
+#ifdef CANT_WRITE_BEFORE_SENDING_FD
+    scache_dummy = vstring_alloc(10);
+#endif
+
+    /*
+     * Disable the max_use limit. We still terminate when no client is
+     * connected for $idle_limit time units.
+     */
+    var_use_limit = 0;
+
+    /*
+     * Dump and reset cache statistics every so often.
+     */
+    event_request_timer(scache_status_update, (void *) 0, var_scache_stat_time);
+    scache_start_time = event_time();
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+/* main - pass control to the multi-threaded skeleton */
+
+int     main(int argc, char **argv)
+{
+    static const CONFIG_TIME_TABLE time_table[] = {
+	VAR_SCACHE_TTL_LIM, DEF_SCACHE_TTL_LIM, &var_scache_ttl_lim, 1, 0,
+	VAR_SCACHE_STAT_TIME, DEF_SCACHE_STAT_TIME, &var_scache_stat_time, 1, 0,
+	0,
+    };
+
+    /*
+     * Fingerprint executables and core dumps.
+     */
+    MAIL_VERSION_STAMP_ALLOCATE;
+
+    multi_server_main(argc, argv, scache_service,
+		      CA_MAIL_SERVER_TIME_TABLE(time_table),
+		      CA_MAIL_SERVER_POST_INIT(post_jail_init),
+		      CA_MAIL_SERVER_EXIT(scache_status_dump),
+		      CA_MAIL_SERVER_SOLITARY,
+		      0);
+}