added capability to use a local interface IP address as fromhost-ip for imuxsock

new config directives: $IMUXSockLocalIPIF

6 files changed, 97 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 99e324ab..78f74695 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+- added capability to use a local interface IP address as fromhost-ip for
+  imuxsock
+  new config directives: $IMUXSockLocalIPIF
 - added configuration directives to customize queue light delay marks
   $MainMsgQueueLightDelayMark, $ActionQueueLightDelayMark; both
   specify number of messages starting at which a delay happens.
diff --git a/doc/imuxsock.html b/doc/imuxsock.html
index ee5db22d..1b79dd0d 100644
--- a/doc/imuxsock.html
+++ b/doc/imuxsock.html
@@ -64,6 +64,11 @@ burst in number of messages. Default is 200.
 <li><b>$IMUXSockRateLimitSeverity</b> [numerical severity] - specifies the severity of
 messages that shall be rate-limited.
 </li>
+<li><b>$IMUXSockLocalIPIF</b> [interface name] - if provided, the IP of the specified
+interface (e.g. "eth0") shall be used as fromhost-ip for imuxsock-originating messages.
+If this directive is not given OR the interface cannot be found (or has no IP address),
+the default of "127.0.0.1" is used.
+</li>
 <li><b>$InputUnixListenSocketUsePIDFromSystem</b> [on/<b>off</b>] - specifies if the pid being logged shall
 be obtained from the log socket itself. If so, the TAG part of the message is rewritten.
 It is recommended to turn this option on, but the default is "off" to keep compatible
@@ -150,7 +155,7 @@ $SystemLogRateLimitInterval 0 # turn off rate limiting
 <p><font size="2">This documentation is part of the
 <a href="http://www.rsyslog.com/">rsyslog</a>
 project.<br>
-Copyright &copy; 2008-2010 by <a href="http://www.gerhards.net/rainer">Rainer
+Copyright &copy; 2008-2012 by <a href="http://www.gerhards.net/rainer">Rainer
 Gerhards</a> and
 <a href="http://www.adiscon.com/">Adiscon</a>.
 Released under the GNU GPL version 3 or higher.</font></p>
diff --git a/plugins/imuxsock/imuxsock.c b/plugins/imuxsock/imuxsock.c
index 4523798f..ad8c81e7 100644
--- a/plugins/imuxsock/imuxsock.c
+++ b/plugins/imuxsock/imuxsock.c
@@ -89,6 +89,7 @@ DEF_IMOD_STATIC_DATA
 DEFobjCurrIf(errmsg)
 DEFobjCurrIf(glbl)
 DEFobjCurrIf(prop)
+DEFobjCurrIf(net)
 DEFobjCurrIf(parser)
 DEFobjCurrIf(datetime)
 DEFobjCurrIf(statsobj)
@@ -157,6 +158,7 @@ static int sd_fds = 0;			/* number of systemd activated sockets */
 /* config settings */
 static int bOmitLocalLogging = 0;
 static uchar *pLogSockName = NULL;
+static uchar *pLocalIPIF = 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? */
@@ -764,6 +766,8 @@ ENDrunInput
 
 
 BEGINwillRun
+	uchar myIP[128];
+	rsRetVal localRet;
 CODESTARTwillRun
 	register int i;
 	int actSocks;
@@ -784,7 +788,7 @@ CODESTARTwillRun
 	else if(sd_booted()) {
 		struct stat st;
 		if(stat(SYSTEMD_JOURNAL, &st) != -1 && S_ISDIR(st.st_mode)) {
-			listeners[0].sockName = SYSTEMD_PATH_LOG;
+			listeners[0].sockName = (uchar*)SYSTEMD_PATH_LOG;
 		}
 	}
 	if(ratelimitIntervalSysSock > 0) {
@@ -826,6 +830,23 @@ CODESTARTwillRun
 	CHKiRet(prop.SetString(pInputName, UCHAR_CONSTANT("imuxsock"), sizeof("imuxsock") - 1));
 	CHKiRet(prop.ConstructFinalize(pInputName));
 
+	if(pLocalIPIF == NULL) {
+		strcpy((char*)myIP, "127.0.0.1");
+	} else {
+		localRet = net.GetIFIPAddr((uchar*)"eth0", AF_UNSPEC, myIP, (int) sizeof(myIP));
+		if(localRet != RS_RET_OK) {
+			DBGPRINTF("imuxsock: could not obtain my IP, using 127.0.0.1 instead\n");
+			strcpy((char*)myIP, "127.0.0.1");
+		}
+	}
+
+	DBGPRINTF("imuxsock: using '%s' as localhost IP\n", myIP);
+
+	CHKiRet(prop.Construct(&pLocalHostIP));
+	CHKiRet(prop.SetString(pLocalHostIP, myIP, ustrlen(myIP)));
+	CHKiRet(prop.ConstructFinalize(pLocalHostIP));
+
+
 finalize_it:
 ENDwillRun
 
@@ -857,6 +878,7 @@ CODESTARTafterRun
 		}
 	/* free no longer needed string */
 	free(pLogSockName);
+	free(pLocalIPIF);
 	free(pLogHostName);
 
 	discardLogSockets();
@@ -901,6 +923,10 @@ static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __a
 		free(pLogSockName);
 		pLogSockName = NULL;
 	}
+	if(pLocalIPIF != NULL) {
+		free(pLocalIPIF);
+		pLocalIPIF = NULL;
+	}
 	if(pLogHostName != NULL) {
 		free(pLogHostName);
 		pLogHostName = NULL;
@@ -931,6 +957,7 @@ CODESTARTmodInit
 CODEmodInit_QueryRegCFSLineHdlr
 	CHKiRet(objUse(errmsg, CORE_COMPONENT));
 	CHKiRet(objUse(glbl, CORE_COMPONENT));
+	CHKiRet(objUse(net, CORE_COMPONENT));
 	CHKiRet(objUse(prop, CORE_COMPONENT));
 	CHKiRet(objUse(statsobj, CORE_COMPONENT));
 	CHKiRet(objUse(datetime, CORE_COMPONENT));
@@ -954,10 +981,6 @@ CODEmodInit_QueryRegCFSLineHdlr
 		listeners[i].fd  = -1;
 	}
 
-	CHKiRet(prop.Construct(&pLocalHostIP));
-	CHKiRet(prop.SetString(pLocalHostIP, UCHAR_CONSTANT("127.0.0.1"), sizeof("127.0.0.1") - 1));
-	CHKiRet(prop.ConstructFinalize(pLocalHostIP));
-
 	/* now init listen socket zero, the local log socket */
 	CHKiRet(prop.Construct(&(listeners[0].hostName)));
 	CHKiRet(prop.SetString(listeners[0].hostName, glbl.GetLocalHostName(), ustrlen(glbl.GetLocalHostName())));
@@ -988,6 +1011,8 @@ CODEmodInit_QueryRegCFSLineHdlr
 		NULL, &ratelimitSeverity, STD_LOADABLE_MODULE_ID));
 	CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler,
 		resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"imuxsocklocalipif", 0, eCmdHdlrGetWord,
+		NULL, &pLocalIPIF, STD_LOADABLE_MODULE_ID));
 	/* the following one is a (dirty) trick: the system log socket is not added via
 	 * an "addUnixListenSocket" config format. As such, it's properties can not be modified
 	 * via $InputUnixListenSocket*". So we need to add a special directive
diff --git a/runtime/net.c b/runtime/net.c
index 4781739f..1264b2cb 100644
--- a/runtime/net.c
+++ b/runtime/net.c
@@ -12,7 +12,7 @@
  * long term, but it is good to have it out of syslogd.c. Maybe this here is
  * an interim location ;)
  *
- * Copyright 2007, 2008 Rainer Gerhards and Adiscon GmbH.
+ * Copyright 2007-2012 Rainer Gerhards and Adiscon GmbH.
  *
  * rgerhards, 2008-04-16: I changed this code to LGPL today. I carefully analyzed
  * that it does not borrow code from the original sysklogd and that I have 
@@ -54,6 +54,9 @@
 #include <fnmatch.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <ifaddrs.h>
+#include <sys/types.h>
+#include <arpa/inet.h>
 
 #include "syslogd-types.h"
 #include "module-template.h"
@@ -1581,6 +1584,54 @@ finalize_it:
 }
 
 
+/* return the IP address (IPv4/6) for the provided interface. Returns
+ * RS_RET_NOT_FOUND if interface can not be found in interface list.
+ * The family must be correct (AF_INET vs. AF_INET6, AF_UNSPEC means
+ * either of *these two*).
+ * The function re-queries the interface list (at least in theory).
+ * However, it caches entries in order to avoid too-frequent requery.
+ * rgerhards, 2012-03-06
+ */
+static rsRetVal
+getIFIPAddr(uchar *szif, int family, uchar *pszbuf, int lenBuf)
+{
+	struct ifaddrs * ifaddrs = NULL;
+	struct ifaddrs * ifa;
+	void * pAddr;
+	DEFiRet;
+
+ 	if(getifaddrs(&ifaddrs) != 0) {
+		ABORT_FINALIZE(RS_RET_ERR);
+	}
+
+	for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
+		if(strcmp(ifa->ifa_name, (char*)szif))
+			continue;
+		if(   (family == AF_INET6 || family == AF_UNSPEC)
+		   && ifa->ifa_addr->sa_family == AF_INET6) {
+			pAddr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
+			inet_ntop(AF_INET6, pAddr, (char*)pszbuf, lenBuf);
+			break;
+		} else if(/*   (family == AF_INET || family == AF_UNSPEC)
+		         &&*/ ifa->ifa_addr->sa_family == AF_INET) {
+			pAddr = &((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
+			inet_ntop(AF_INET, pAddr, (char*)pszbuf, lenBuf);
+			break;
+		} 
+	}
+
+	if(ifaddrs != NULL)
+		freeifaddrs(ifaddrs);
+
+	if(ifa == NULL)
+		iRet = RS_RET_NOT_FOUND;
+
+finalize_it:
+	RETiRet;
+
+}
+
+
 /* queryInterface function
  * rgerhards, 2008-03-05
  */
@@ -1612,6 +1663,7 @@ CODESTARTobjQueryInterface(net)
 	pIf->PermittedPeerWildcardMatch = PermittedPeerWildcardMatch;
 	pIf->CmpHost = CmpHost;
 	pIf->HasRestrictions = HasRestrictions;
+	pIf->GetIFIPAddr = getIFIPAddr;
 	/* data members */
 	pIf->pACLAddHostnameOnFail = &ACLAddHostnameOnFail;
 	pIf->pACLDontResolve = &ACLDontResolve;
diff --git a/runtime/net.h b/runtime/net.h
index 101ce79d..1b41c81c 100644
--- a/runtime/net.h
+++ b/runtime/net.h
@@ -1,6 +1,6 @@
 /* Definitions for network-related stuff.
  *
- * Copyright 2007, 2008 Rainer Gerhards and Adiscon GmbH.
+ * Copyright 2007-2012 Rainer Gerhards and Adiscon GmbH.
  *
  * This file is part of the rsyslog runtime library.
  *
@@ -151,11 +151,13 @@ BEGINinterface(net) /* name must also be changed in ENDinterface macro! */
 	/* v6 interface additions - 2009-11-16 */
 	rsRetVal (*HasRestrictions)(uchar *, int *bHasRestrictions);
 	int (*isAllowedSender2)(uchar *pszType, struct sockaddr *pFrom, const char *pszFromHost, int bChkDNS);
+	/* v7 interface additions - 2012-03-06 */
+	rsRetVal (*GetIFIPAddr)(uchar *szif, int family, uchar *pszbuf, int lenBuf);
 	/* data members - these should go away over time... TODO */
 	int    *pACLAddHostnameOnFail; /* add hostname to acl when DNS resolving has failed */
 	int    *pACLDontResolve;       /* add hostname to acl instead of resolving it to IP(s) */
 ENDinterface(net)
-#define netCURR_IF_VERSION 6 /* increment whenever you change the interface structure! */
+#define netCURR_IF_VERSION 7 /* increment whenever you change the interface structure! */
 
 /* prototypes */
 PROTOTYPEObj(net);
diff --git a/tools/syslogd.c b/tools/syslogd.c
index c0e663d2..02a0dad6 100644
--- a/tools/syslogd.c
+++ b/tools/syslogd.c
@@ -2712,6 +2712,7 @@ int realMain(int argc, char **argv)
 				CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_aliases[i]));
 			} else {
 				CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_name));
+				int i;
 			}
 
 			if((p = (uchar*)strchr((char*)LocalHostName, '.')))