1 files changed, 296 insertions, 0 deletions
diff --git a/plugins/imudp/imudp.c b/plugins/imudp/imudp.c
new file mode 100644
index 00000000..cda794c3
--- /dev/null
+++ b/plugins/imudp/imudp.c
@@ -0,0 +1,296 @@
+/* imudp.c
+ * This is the implementation of the UDP input module.
+ *
+ * NOTE: read comments in module-template.h to understand how this file
+ *       works!
+ *
+ * File begun on 2007-12-21 by RGerhards (extracted from syslogd.c)
+ *
+ * Copyright 2007 Rainer Gerhards and Adiscon GmbH.
+ *
+ * This file is part of rsyslog.
+ *
+ * Rsyslog is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Rsyslog is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Rsyslog.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * A copy of the GPL can be found in the file "COPYING" in this distribution.
+ */
+#include "config.h"
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <netdb.h>
+#include "rsyslog.h"
+#include "syslogd.h"
+#include "net.h"
+#include "cfsysline.h"
+#include "module-template.h"
+#include "srUtils.h"
+#include "errmsg.h"
+
+MODULE_TYPE_INPUT
+
+/* defines */
+
+/* Module static data */
+DEF_IMOD_STATIC_DATA
+DEFobjCurrIf(errmsg)
+DEFobjCurrIf(net)
+
+static int *udpLstnSocks = NULL;	/* Internet datagram sockets, first element is nbr of elements
+					 * read-only after init(), but beware of restart! */
+static uchar *pszBindAddr = NULL;	/* IP to bind socket to */
+static uchar *pRcvBuf = NULL;		/* receive buffer (for a single packet). We use a global and alloc
+					 * it so that we can check available memory in willRun() and request
+					 * termination if we can not get it. -- rgerhards, 2007-12-27
+					 */
+
+/* config settings */
+
+
+/* This function is called when a new listener shall be added. It takes
+ * the configured parameters, tries to bind the socket and, if that
+ * succeeds, adds it to the list of existing listen sockets.
+ * rgerhards, 2007-12-27
+ */
+static rsRetVal addListner(void __attribute__((unused)) *pVal, uchar *pNewVal)
+{
+	DEFiRet;
+	uchar *bindAddr;
+	int *newSocks;
+	int *tmpSocks;
+	int iSrc, iDst;
+
+	/* check which address to bind to. We could do this more compact, but have not
+	 * done so in order to make the code more readable. -- rgerhards, 2007-12-27
+	 */
+	if(pszBindAddr == NULL)
+		bindAddr = NULL;
+	else if(pszBindAddr[0] == '*' && pszBindAddr[1] == '\0')
+		bindAddr = NULL;
+	else
+		bindAddr = pszBindAddr;
+
+	dbgprintf("Trying to open syslog UDP ports at %s:%s.\n",
+		  (bindAddr == NULL) ? (uchar*)"*" : bindAddr, pNewVal);
+
+	newSocks = net.create_udp_socket(bindAddr, (pNewVal == NULL || *pNewVal == '\0') ? (uchar*) "514" : pNewVal, 1);
+	if(newSocks != NULL) {
+		/* we now need to add the new sockets to the existing set */
+		if(udpLstnSocks == NULL) {
+			/* esay, we can just replace it */
+			udpLstnSocks = newSocks;
+		} else {
+			/* we need to add them */
+			if((tmpSocks = malloc(sizeof(int) * 1 + newSocks[0] + udpLstnSocks[0])) == NULL) {
+				dbgprintf("out of memory trying to allocate udp listen socket array\n");
+				/* in this case, we discard the new sockets but continue with what we
+				 * already have
+				 */
+				free(newSocks);
+				ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
+			} else {
+				/* ready to copy */
+				iDst = 1;
+				for(iSrc = 1 ; iSrc <= udpLstnSocks[0] ; ++iSrc)
+					tmpSocks[iDst++] = udpLstnSocks[iSrc];
+				for(iSrc = 1 ; iSrc <= newSocks[0] ; ++iSrc)
+					tmpSocks[iDst++] = newSocks[iSrc];
+				tmpSocks[0] = udpLstnSocks[0] + newSocks[0];
+				free(newSocks);
+				free(udpLstnSocks);
+				udpLstnSocks = tmpSocks;
+			}
+		}
+	}
+
+finalize_it:
+	free(pNewVal); /* in any case, this is no longer needed */
+
+	RETiRet;
+}
+
+
+/* This function is called to gather input.
+ */
+BEGINrunInput
+	int maxfds;
+	int nfds;
+	int i;
+	fd_set readfds;
+	struct sockaddr_storage frominet;
+	socklen_t socklen;
+	uchar fromHost[NI_MAXHOST];
+	uchar fromHostFQDN[NI_MAXHOST];
+	ssize_t l;
+CODESTARTrunInput
+	/* this is an endless loop - it is terminated when the thread is
+	 * signalled to do so. This, however, is handled by the framework,
+	 * right into the sleep below.
+	 */
+	while(1) {
+		/* Add the Unix Domain Sockets to the list of read
+		 * descriptors.
+		 * rgerhards 2005-08-01: we must now check if there are
+		 * any local sockets to listen to at all. If the -o option
+		 * is given without -a, we do not need to listen at all..
+		 */
+	        maxfds = 0;
+	        FD_ZERO (&readfds);
+
+		/* Add the UDP listen sockets to the list of read descriptors.
+		 */
+		if(udpLstnSocks != NULL) {
+                        for (i = 0; i < *udpLstnSocks; i++) {
+                                if (udpLstnSocks[i+1] != -1) {
+					if(Debug)
+						net.debugListenInfo(udpLstnSocks[i+1], "UDP");
+                                        FD_SET(udpLstnSocks[i+1], &readfds);
+					if(udpLstnSocks[i+1]>maxfds) maxfds=udpLstnSocks[i+1];
+				}
+                        }
+		}
+		if(Debug) {
+			dbgprintf("--------imUDP calling select, active file descriptors (max %d): ", maxfds);
+			for (nfds = 0; nfds <= maxfds; ++nfds)
+				if ( FD_ISSET(nfds, &readfds) )
+					dbgprintf("%d ", nfds);
+			dbgprintf("\n");
+		}
+
+		/* wait for io to become ready */
+		nfds = select(maxfds+1, (fd_set *) &readfds, NULL, NULL, NULL);
+
+		if(udpLstnSocks != NULL) {
+		       for (i = 0; nfds && i < *udpLstnSocks; i++) {
+			       if (FD_ISSET(udpLstnSocks[i+1], &readfds)) {
+				       socklen = sizeof(frominet);
+				       l = recvfrom(udpLstnSocks[i+1], (char*) pRcvBuf, MAXLINE - 1, 0,
+						    (struct sockaddr *)&frominet, &socklen);
+				       if (l > 0) {
+					       if(net.cvthname(&frominet, fromHost, fromHostFQDN) == RS_RET_OK) {
+						       dbgprintf("Message from inetd socket: #%d, host: %s\n",
+							       udpLstnSocks[i+1], fromHost);
+						       /* 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
+							*/
+						       if(net.isAllowedSender(net.pAllowedSenders_UDP,
+							  (struct sockaddr *)&frominet, (char*)fromHostFQDN)) {
+							       parseAndSubmitMessage((char*)fromHost, (char*) pRcvBuf, l,
+							       MSG_PARSE_HOSTNAME, NOFLAG, eFLOWCTL_NO_DELAY);
+						       } else {
+							       dbgprintf("%s is not an allowed sender\n", (char*)fromHostFQDN);
+							       if(option_DisallowWarning) {
+								       errmsg.LogError(NO_ERRCODE, "UDP message from disallowed sender %s discarded",
+										  (char*)fromHost);
+							       }	
+						       }
+					       }
+				       } else if (l < 0 && errno != EINTR && errno != EAGAIN) {
+						char errStr[1024];
+						rs_strerror_r(errno, errStr, sizeof(errStr));
+						dbgprintf("INET socket error: %d = %s.\n", errno, errStr);
+						       errmsg.LogError(NO_ERRCODE, "recvfrom inet");
+						       /* should be harmless */
+						       sleep(1);
+					       }
+					--nfds; /* indicate we have processed one */
+				}
+		       }
+		}
+	}
+
+	return iRet;
+ENDrunInput
+
+
+/* initialize and return if will run or not */
+BEGINwillRun
+CODESTARTwillRun
+	net.PrintAllowedSenders(1); /* UDP */
+
+	/* if we could not set up any listners, there is no point in running... */
+	if(udpLstnSocks == NULL)
+		ABORT_FINALIZE(RS_RET_NO_RUN);
+
+	if((pRcvBuf = malloc(MAXLINE * sizeof(char))) == NULL) {
+		ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
+	}
+finalize_it:
+ENDwillRun
+
+
+BEGINafterRun
+CODESTARTafterRun
+	/* do cleanup here */
+	if (net.pAllowedSenders_UDP != NULL) {
+		net.clearAllowedSenders (net.pAllowedSenders_UDP);
+		net.pAllowedSenders_UDP = NULL;
+	}
+	if(udpLstnSocks != NULL)
+		net.closeUDPListenSockets(udpLstnSocks);
+	if(pRcvBuf != NULL)
+		free(pRcvBuf);
+ENDafterRun
+
+
+BEGINmodExit
+CODESTARTmodExit
+	/* release what we no longer need */
+	objRelease(errmsg, CORE_COMPONENT);
+	objRelease(net, LM_NET_FILENAME);
+ENDmodExit
+
+
+BEGINqueryEtryPt
+CODESTARTqueryEtryPt
+CODEqueryEtryPt_STD_IMOD_QUERIES
+ENDqueryEtryPt
+
+static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __attribute__((unused)) *pVal)
+{
+	if(pszBindAddr != NULL) {
+		free(pszBindAddr);
+		pszBindAddr = NULL;
+	}
+	if(udpLstnSocks != NULL) {
+		net.closeUDPListenSockets(udpLstnSocks);
+		udpLstnSocks = NULL;
+	}
+	return RS_RET_OK;
+}
+
+
+BEGINmodInit()
+CODESTARTmodInit
+	*ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */
+CODEmodInit_QueryRegCFSLineHdlr
+	CHKiRet(objUse(errmsg, CORE_COMPONENT));
+	CHKiRet(objUse(net, LM_NET_FILENAME));
+
+	/* register config file handlers */
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"udpserverrun", 0, eCmdHdlrGetWord,
+		addListner, NULL, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"udpserveraddress", 0, eCmdHdlrGetWord,
+		NULL, &pszBindAddr, STD_LOADABLE_MODULE_ID));
+	CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler,
+		resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID));
+ENDmodInit
+/*
+ * vi:set ai:
+ */