moved DNS resolution code out of imudp and into the backend processing

Most importantly, DNS resolution now never happens if the resolved name
is not required. Note that this applies to imudp - for the other inputs,
DNS resolution almost comes for free, so we do not do it there. However,
the new method has been implemented in a generic way and as such may
also be used by other modules in the future.

1 files changed, 83 insertions, 11 deletions

diff --git a/tools/syslogd.c b/tools/syslogd.c
index 820cf273..3fc3da0d 100644
--- a/tools/syslogd.c
+++ b/tools/syslogd.c
@@ -586,6 +586,82 @@ finalize_it:
 	RETiRet;
 }
 
+/* check message against ACL set
+ * rgerhards, 2009-11-16
+ */
+#if 0
+static inline rsRetVal
+chkMsgAgainstACL() {
+	/* if we reach this point, we had a good receive and can process the packet received */
+	/* check if we have a different sender than before, if so, we need to query some new values */
+	if(net.CmpHost(&frominet, frominetPrev, socklen) != 0) {
+		CHKiRet(net.cvthname(&frominet, fromHost, fromHostFQDN, fromHostIP));
+		memcpy(frominetPrev, &frominet, socklen); /* update cache indicator */
+		/* Here we check if a host is permitted to send us
+		* syslog messages. If it isn't, we do not further
+		* process the message but log a warning (if we are
+		* configured to do this).
+		* rgerhards, 2005-09-26
+		*/
+		*pbIsPermitted = net.isAllowedSender((uchar*)"UDP",
+						    (struct sockaddr *)&frominet, (char*)fromHostFQDN);
+
+		if(!*pbIsPermitted) {
+			DBGPRINTF("%s is not an allowed sender\n", (char*)fromHostFQDN);
+			if(glbl.GetOption_DisallowWarning) {
+				time_t tt;
+
+				datetime.GetTime(&tt);
+				if(tt > ttLastDiscard + 60) {
+					ttLastDiscard = tt;
+					errmsg.LogError(0, NO_ERRCODE,
+					"UDP message from disallowed sender %s discarded",
+					(char*)fromHost);
+				}
+			}
+		}
+	}
+}
+#endif
+
+
+/* consumes a single messages - this function is primarily used to shuffle
+ * out some code from msgConsumer(). After this function, the message is
+ * (by definition!) considered committed.
+ * rgerhards, 2009-11-16
+ */
+static inline rsRetVal
+msgConsumeOne(msg_t *pMsg, prop_t **propFromHost, prop_t **propFromHostIP) {
+	uchar fromHost[NI_MAXHOST];
+	uchar fromHostIP[NI_MAXHOST];
+	uchar fromHostFQDN[NI_MAXHOST];
+	int bIsPermitted;
+	DEFiRet;
+
+	if((pMsg->msgFlags & NEEDS_ACLCHK_U) != 0) {
+		dbgprintf("msgConsumer: UDP ACL must be checked for message (hostname-based)\n");
+		CHKiRet(net.cvthname(pMsg->rcvFrom.pfrominet, fromHost, fromHostFQDN, fromHostIP));
+		bIsPermitted = net.isAllowedSender2((uchar*)"UDP",
+		    (struct sockaddr *)pMsg->rcvFrom.pfrominet, (char*)fromHostFQDN, 1);
+		if(!bIsPermitted) {
+			DBGPRINTF("Message from '%s' discarded, not a permitted sender host\n",
+				  fromHostFQDN);
+			ABORT_FINALIZE(RS_RET_ERR);
+		/* save some of the info we obtained */
+		MsgSetRcvFromStr(pMsg, fromHost, ustrlen(fromHost), propFromHost);
+		CHKiRet(MsgSetRcvFromIPStr(pMsg, fromHostIP, ustrlen(fromHostIP), propFromHostIP));
+		pMsg->msgFlags &= ~NEEDS_ACLCHK_U;
+		}
+	}
+
+	if((pMsg->msgFlags & NEEDS_PARSING) != 0)
+		CHKiRet(parser.ParseMsg(pMsg));
+
+	ruleset.ProcessMsg(pMsg);
+finalize_it:
+	RETiRet;
+}
+
 
 /* The consumer of dequeued messages. This function is called by the
  * queue engine on dequeueing of a message. It runs on a SEPARATE
@@ -597,26 +673,22 @@ static rsRetVal
 msgConsumer(void __attribute__((unused)) *notNeeded, batch_t *pBatch, int *pbShutdownImmediate)
 {
 	int i;
-	msg_t *pMsg;
-	rsRetVal localRet;
+	prop_t *propFromHost = NULL;
+	prop_t *propFromHostIP = NULL;
 	DEFiRet;
 
 	assert(pBatch != NULL);
 
 	for(i = 0 ; i < pBatch->nElem  && !*pbShutdownImmediate ; i++) {
-		pMsg = (msg_t*) pBatch->pElem[i].pUsrp;
 		DBGPRINTF("msgConsumer processes msg %d/%d\n", i, pBatch->nElem);
-		if((pMsg->msgFlags & NEEDS_PARSING) != 0) {
-			localRet = parser.ParseMsg(pMsg);
-			if(localRet == RS_RET_OK)
-				ruleset.ProcessMsg(pMsg);
-		} else {
-			ruleset.ProcessMsg(pMsg);
-		}
-		/* if we reach this point, the message is considered committed (by definition!) */
+		msgConsumeOne((msg_t*) pBatch->pElem[i].pUsrp, &propFromHost, &propFromHostIP);
 		pBatch->pElem[i].state = BATCH_STATE_COMM;
 	}
 
+	if(propFromHost != NULL)
+		prop.Destruct(&propFromHost);
+	if(propFromHostIP != NULL)
+		prop.Destruct(&propFromHostIP);
 	RETiRet;
 }