added new config option $InputUnixListenSocketCreatePath

to permit the auto-creation of pathes to additional log sockets. This
turns out to be useful if they reside on temporary file systems and
rsyslogd starts up before the daemons that create these sockets
(rsyslogd always creates the socket itself if it does not exist).

3 files changed, 43 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index dbb9e0b7..0e36da85 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,11 @@ Version 5.3.0  [DEVEL] (rgerhards), 2009-08-??
   this option permites to process mark messages under all circumstances,
   even if an action was recently called. This can be useful to use mark
   messages as a kind of heartbeat.
+- added new config option $InputUnixListenSocketCreatePath
+  to permit the auto-creation of pathes to additional log sockets. This
+  turns out to be useful if they reside on temporary file systems and
+  rsyslogd starts up before the daemons that create these sockets
+  (rsyslogd always creates the socket itself if it does not exist).
 - added $LogRSyslogStatusMessages configuration directive
   permitting to turn off rsyslog start/stop/HUP messages. See Debian
   ticket http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=463793
diff --git a/doc/imuxsock.html b/doc/imuxsock.html
index 472470a0..15c365a6 100644
--- a/doc/imuxsock.html
+++ b/doc/imuxsock.html
@@ -46,6 +46,18 @@ Ignore timestamps included in the messages, applies to messages received via the
 <li><b>$SystemLogSocketName</b> &lt;name-of-socket&gt; -- former -p option</li>
 <li><b>$SystemLogFlowControl</b> [on/<b>off</b>] - specifies if flow control should be applied
 to the system log socket.</li>
+<li><b>$InputUnixListenSocketCreatePath</b> [on/<b>off</b>] - create directories in the socket path
+if they do not already exist. They are created with 0755 permissions with the owner being the process under
+which rsyslogd runs. The default is not to create directories. Keep in mind, though, that rsyslogd always
+creates the socket itself if it does not exist (just not the directories by default).
+<br>Note that this statement affects the
+next $AddUnixListenSocket directive that follows in sequence in the configuration file. It never works
+on the system log socket (where it is deemed unnecessary). Also note that it is automatically 
+being reset to &quot;off&quot; after the $AddUnixListenSocket directive, so if you would have it active
+for two additional listen sockets, you need to specify it in front of each one. This option is primarily considered
+useful for defining additional sockets that reside on non-permanent file systems. As rsyslogd probably starts
+up before the daemons that create these sockets, it is a vehicle to enable rsyslogd to listen to those
+sockets even though their directories do not yet exist. [available since 4.7.0 and 5.3.0]</li>
 <li><b>$AddUnixListenSocket</b> &lt;name-of-socket&gt; adds additional unix socket, default none -- former -a option</li>
 <li><b>$InputUnixListenSocketHostName</b> &lt;hostname&gt; permits to override the hostname that
 shall be used inside messages taken from the <b>next</b> $AddUnixListenSocket socket. Note that
@@ -57,20 +69,32 @@ that the local hostname can be overridden in cases where that is desired.</li>
 <br>
 This documentation is sparse and incomplete.
 <p><b>Sample:</b></p>
-<p>The following sample is the minimum setup required to accept syslog messages from applications running on the local system.<br>
+<p>The following sample is the minimum setup required to accept syslog messages from applications running
+on the local system.<br>
 </p>
 <textarea rows="2" cols="70">$ModLoad imuxsock # needs to be done just once
 $SystemLogSocketFlowControl on # enable flow control (use if needed)
 </textarea>
 <p>The following sample is a configuration where rsyslogd pulls logs from two
 jails, and assigns different hostnames to each of the jails: </p>
-<textarea rows="6" cols="60">$ModLoad imuxsock # needs to be done just once
+<textarea rows="6" cols="70">$ModLoad imuxsock # needs to be done just once
 
 $InputUnixListenSocketHostName jail1.example.net
 $AddUnixListenSocket /jail/1/dev/log
 $InputUnixListenSocketHostName jail2.example.net
 $AddUnixListenSocket /jail/2/dev/log
 </textarea>
+<p>The following sample is a configuration where rsyslogd reads the openssh log
+messages via a separate socket, but this socket is created on a temporary file
+system. As rsyslogd starts up before the sshd, it needs to create the socket
+directories, because it otherwise can not open the socket and thus not listen
+to openssh messages. Note that it is vital not to place any other socket between
+the $InputUnixListenSocketCreatePath and the $InputUnixListenSocketHostName.</p>
+<textarea rows="6" cols="70">$ModLoad imuxsock # needs to be done just once
+
+$InputUnixListenSocketCreatePath on # turn on for *next* socket
+$InputUnixListenSocketHostName /var/run/sshd/dev/log
+</textarea>
 <p>[<a href="rsyslog_conf.html">rsyslog.conf overview</a>]
 [<a href="manual.html">manual index</a>] [<a href="http://www.rsyslog.com/">rsyslog site</a>]</p>
 <p><font size="2">This documentation is part of the
diff --git a/plugins/imuxsock/imuxsock.c b/plugins/imuxsock/imuxsock.c
index c099be56..b8da4966 100644
--- a/plugins/imuxsock/imuxsock.c
+++ b/plugins/imuxsock/imuxsock.c
@@ -77,6 +77,7 @@ static int startIndexUxLocalSockets; /* process funix from that index on (used t
 				   */
 static int funixParseHost[MAXFUNIX] = { 0, }; /* should parser parse host name?  read-only after startup */
 static int funixFlags[MAXFUNIX] = { IGNDATE, }; /* should parser parse host name?  read-only after startup */
+static int funixCreateSockPath[MAXFUNIX] = { 0, }; /* auto-creation of socket directory? */
 static uchar *funixn[MAXFUNIX] = { (uchar*) _PATH_LOG }; /* read-only after startup */
 static uchar *funixHName[MAXFUNIX] = { NULL, }; /* host-name override - if set, use this instead of actual name */
 static int funixFlowCtl[MAXFUNIX] = { eFLOWCTL_NO_DELAY, }; /* flow control settings for this socket */
@@ -89,6 +90,8 @@ static uchar *pLogSockName = NULL;
 static uchar *pLogHostName = NULL;	/* host name to use with this socket */
 static int bUseFlowCtl = 0;		/* use flow control or not (if yes, only LIGHT is used! */
 static int bIgnoreTimestamp = 1; /* ignore timestamps present in the incoming message? */
+#define DFLT_bCreateSockPath 0
+static int bCreateSockPath = DFLT_bCreateSockPath; /* auto-create socket path? */
 
 
 /* set the timestamp ignore / not ignore option for the system
@@ -132,6 +135,7 @@ static rsRetVal addLstnSocketName(void __attribute__((unused)) *pVal, uchar *pNe
 		pLogHostName = NULL; /* re-init for next, not freed because funixHName[] now owns it */
 		funixFlowCtl[nfunix] = bUseFlowCtl ? eFLOWCTL_LIGHT_DELAY : eFLOWCTL_NO_DELAY;
 		funixFlags[nfunix] = bIgnoreTimestamp ? IGNDATE : NOFLAG;
+		funixCreateSockPath[nfunix] = bCreateSockPath;
 		funixn[nfunix++] = pNewVal;
 	}
 	else {
@@ -165,7 +169,7 @@ static rsRetVal discardFunixn(void)
 }
 
 
-static int create_unix_socket(const char *path)
+static int create_unix_socket(const char *path, int bCreatePath)
 {
 	struct sockaddr_un sunx;
 	int fd;
@@ -177,6 +181,9 @@ static int create_unix_socket(const char *path)
 
 	memset(&sunx, 0, sizeof(sunx));
 	sunx.sun_family = AF_UNIX;
+	if(bCreatePath) {
+		makeFileParentDirs((uchar*)path, strlen(path), 0755, -1, -1, 0);
+	}
 	(void) strncpy(sunx.sun_path, path, sizeof(sunx.sun_path));
 	fd = socket(AF_UNIX, SOCK_DGRAM, 0);
 	if (fd < 0 || bind(fd, (struct sockaddr *) &sunx, SUN_LEN(&sunx)) < 0 ||
@@ -308,7 +315,7 @@ CODESTARTwillRun
 
 	/* initialize and return if will run or not */
 	for (i = startIndexUxLocalSockets ; i < nfunix ; i++) {
-		if ((funix[i] = create_unix_socket((char*) funixn[i])) != -1)
+		if ((funix[i] = create_unix_socket((char*) funixn[i], funixCreateSockPath[i])) != -1)
 			dbgprintf("Opened UNIX socket '%s' (fd %d).\n", funixn[i], funix[i]);
 	}
 
@@ -383,6 +390,7 @@ static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __a
 	nfunix = 1;
 	bIgnoreTimestamp = 1;
 	bUseFlowCtl = 0;
+	bCreateSockPath = DFLT_bCreateSockPath;
 
 	return RS_RET_OK;
 }
@@ -416,6 +424,8 @@ CODEmodInit_QueryRegCFSLineHdlr
 		NULL, &pLogHostName, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr((uchar *)"inputunixlistensocketflowcontrol", 0, eCmdHdlrBinary,
 		NULL, &bUseFlowCtl, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"inputunixlistensocketcreatepath", 0, eCmdHdlrBinary,
+		NULL, &bCreateSockPath, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr((uchar *)"addunixlistensocket", 0, eCmdHdlrGetWord,
 		addLstnSocketName, NULL, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler,