converted netstrm into generic netstrm and the nsd_pctp driver

1 files changed, 579 insertions, 0 deletions

diff --git a/runtime/nsd_ptcp.c b/runtime/nsd_ptcp.c
new file mode 100644
index 00000000..98de5802
--- /dev/null
+++ b/runtime/nsd_ptcp.c
@@ -0,0 +1,579 @@
+/* nsd_ptcp.c
+ *
+ * An implementation of the nsd interface for plain tcp sockets.
+ * 
+ * Copyright 2007, 2008 Rainer Gerhards and Adiscon GmbH.
+ *
+ * This file is part of the rsyslog runtime library.
+ *
+ * The rsyslog runtime library is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The rsyslog runtime library 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the rsyslog runtime library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * A copy of the GPL can be found in the file "COPYING" in this distribution.
+ * A copy of the LGPL can be found in the file "COPYING.LESSER" in this distribution.
+ */
+#include "config.h"
+
+#include "rsyslog.h"
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <signal.h>
+#include <ctype.h>
+#include <netdb.h>
+#include <fnmatch.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "syslogd-types.h"
+#include "module-template.h"
+#include "parse.h"
+#include "srUtils.h"
+#include "obj.h"
+#include "errmsg.h"
+#include "net.h"
+#include "nsd_ptcp.h"
+
+MODULE_TYPE_LIB
+
+/* static data */
+DEFobjStaticHelpers
+DEFobjCurrIf(errmsg)
+DEFobjCurrIf(glbl)
+DEFobjCurrIf(net)
+
+
+/* Standard-Constructor
+ */
+BEGINobjConstruct(nsd_ptcp) /* be sure to specify the object type also in END macro! */
+	pThis->sock = -1;
+	pThis->iSessMax = 500;	/* default max nbr of sessions -TODO:make configurable--rgerhards, 2008-04-17*/
+ENDobjConstruct(nsd_ptcp)
+
+
+/* destructor for the nsd_ptcp object */
+BEGINobjDestruct(nsd_ptcp) /* be sure to specify the object type also in END and CODESTART macros! */
+	int i;
+CODESTARTobjDestruct(nsd_pctp)
+	if(pThis->sock != -1) {
+		close(pThis->sock);
+		pThis->sock = -1;
+	}
+
+	if(pThis->socks != NULL) {
+		/* if we have some sockets at this stage, we need to close them */
+		for(i = 1 ; i <= pThis->socks[0] ; ++i)
+			close(pThis->socks[i]);
+		free(pThis->socks);
+	}
+
+	if(pThis->pRemHostIP != NULL)
+		free(pThis->pRemHostIP);
+	if(pThis->pRemHostName != NULL)
+		free(pThis->pRemHostName);
+ENDobjDestruct(nsd_ptcp)
+
+
+/* abort a connection. This is meant to be called immediately
+ * before the Destruct call. -- rgerhards, 2008-03-24
+ */
+static rsRetVal
+Abort(nsd_t *pNsd)
+{
+	struct linger ling;
+	nsd_ptcp_t *pThis = (nsd_ptcp_t*) pNsd;
+
+	DEFiRet;
+	ISOBJ_TYPE_assert((pThis), nsd_ptcp);
+
+	if((pThis)->sock != -1) {
+		ling.l_onoff = 1;
+		ling.l_linger = 0;
+       		if(setsockopt((pThis)->sock, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling)) < 0 ) {
+			dbgprintf("could not set SO_LINGER, errno %d\n", errno);
+		}
+	}
+
+	RETiRet;
+}
+
+
+/* Set pRemHost based on the address provided. This is to be called upon accept()ing
+ * a connection request. It must be provided by the socket we received the
+ * message on as well as a NI_MAXHOST size large character buffer for the FQDN.
+ * Please see http://www.hmug.org/man/3/getnameinfo.php (under Caveats)
+ * for some explanation of the code found below. If we detect a malicious
+ * hostname, we return RS_RET_MALICIOUS_HNAME and let the caller decide
+ * on how to deal with that.
+ * rgerhards, 2008-03-31
+ */
+static rsRetVal
+FillRemHost(nsd_ptcp_t *pThis, struct sockaddr *pAddr)
+{
+	int error;
+	uchar szIP[NI_MAXHOST] = "";
+	uchar szHname[NI_MAXHOST] = "";
+	struct addrinfo hints, *res;
+	size_t len;
+	
+	DEFiRet;
+	ISOBJ_TYPE_assert(pThis, nsd_ptcp);
+	assert(pAddr != NULL);
+
+        error = getnameinfo(pAddr, SALEN(pAddr), (char*)szIP, sizeof(szIP), NULL, 0, NI_NUMERICHOST);
+
+        if(error) {
+                dbgprintf("Malformed from address %s\n", gai_strerror(error));
+		strcpy((char*)szHname, "???");
+		strcpy((char*)szIP, "???");
+		ABORT_FINALIZE(RS_RET_INVALID_HNAME);
+	}
+
+	if(!glbl.GetDisableDNS()) {
+		error = getnameinfo(pAddr, SALEN(pAddr), (char*)szHname, NI_MAXHOST, NULL, 0, NI_NAMEREQD);
+		if(error == 0) {
+			memset (&hints, 0, sizeof (struct addrinfo));
+			hints.ai_flags = AI_NUMERICHOST;
+			hints.ai_socktype = SOCK_STREAM;
+			/* we now do a lookup once again. This one should fail,
+			 * because we should not have obtained a non-numeric address. If
+			 * we got a numeric one, someone messed with DNS!
+			 */
+			if(getaddrinfo((char*)szHname, NULL, &hints, &res) == 0) {
+				freeaddrinfo (res);
+				/* OK, we know we have evil, so let's indicate this to our caller */
+				snprintf((char*)szHname, NI_MAXHOST, "[MALICIOUS:IP=%s]", szIP);
+				dbgprintf("Malicious PTR record, IP = \"%s\" HOST = \"%s\"", szIP, szHname);
+				iRet = RS_RET_MALICIOUS_HNAME;
+			}
+		} else {
+			strcpy((char*)szHname, (char*)szIP);
+		}
+	} else {
+		strcpy((char*)szHname, (char*)szIP);
+	}
+
+	/* We now have the names, so now let's allocate memory and store them permanently.
+	 * (side note: we may hold on to these values for quite a while, thus we trim their
+	 * memory consumption)
+	 */
+	len = strlen((char*)szIP) + 1; /* +1 for \0 byte */
+	if((pThis->pRemHostIP = malloc(len)) == NULL)
+		ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
+	memcpy(pThis->pRemHostIP, szIP, len);
+
+	len = strlen((char*)szHname) + 1; /* +1 for \0 byte */
+	if((pThis->pRemHostName = malloc(len)) == NULL) {
+		free(pThis->pRemHostIP); /* prevent leak */
+		pThis->pRemHostIP = NULL;
+		ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
+	}
+	memcpy(pThis->pRemHostName, szHname, len);
+
+finalize_it:
+	RETiRet;
+}
+
+
+
+/* accept an incoming connection request, sock provides the socket on which we can
+ * accept the new session.
+ * rgerhards, 2008-03-17
+ */
+static rsRetVal
+AcceptConnReq(nsd_t **ppThis, int sock)
+{
+	int sockflags;
+	struct sockaddr_storage addr;
+	socklen_t addrlen = sizeof(addr);
+	nsd_ptcp_t *pThis = NULL;
+	int iNewSock = -1;
+
+	DEFiRet;
+	assert(ppThis != NULL);
+
+	iNewSock = accept(sock, (struct sockaddr*) &addr, &addrlen);
+	if(iNewSock < 0) {
+		ABORT_FINALIZE(RS_RET_ACCEPT_ERR);
+	}
+
+	/* construct our object so that we can use it... */
+	CHKiRet(nsd_ptcpConstruct(&pThis));
+
+	CHKiRet(FillRemHost(pThis, (struct sockaddr*) &addr));
+
+	/* set the new socket to non-blocking IO */
+	if((sockflags = fcntl(iNewSock, F_GETFL)) != -1) {
+		sockflags |= O_NONBLOCK;
+		/* SETFL could fail too, so get it caught by the subsequent
+		 * error check.
+		 */
+		sockflags = fcntl(iNewSock, F_SETFL, sockflags);
+	}
+	if(sockflags == -1) {
+		dbgprintf("error %d setting fcntl(O_NONBLOCK) on tcp socket %d", errno, iNewSock);
+		ABORT_FINALIZE(RS_RET_IO_ERROR);
+	}
+
+	pThis->sock = iNewSock;
+
+	*ppThis = (nsd_t*) pThis;
+
+finalize_it:
+	if(iRet != RS_RET_OK) {
+		if(pThis != NULL)
+			nsd_ptcpDestruct(&pThis);
+		/* the close may be redundant, but that doesn't hurt... */
+		if(iNewSock >= 0)
+			close(iNewSock);
+	}
+
+	RETiRet;
+}
+
+
+/* initialize the tcp socket for a listner
+ * pLstnPort must point to a port name or number. NULL is NOT permitted
+ * (hint: we need to be careful when we use this module together with librelp,
+ * there NULL indicates the default port
+ * default is used.
+ * gerhards, 2008-03-17
+ */
+static rsRetVal
+LstnInit(nsd_t *pNsd, uchar *pLstnPort)
+{
+	nsd_ptcp_t *pThis = (nsd_ptcp_t*) pNsd;
+        struct addrinfo hints, *res, *r;
+        int error, maxs, *s, on = 1;
+	int sockflags;
+
+	DEFiRet;
+	ISOBJ_TYPE_assert(pThis, nsd_ptcp);
+	assert(pLstnPort != NULL);
+
+	dbgprintf("creating tcp listen socket on port %s\n", pLstnPort);
+
+        memset(&hints, 0, sizeof(hints));
+        hints.ai_flags = AI_PASSIVE;
+        hints.ai_family = glbl.GetDefPFFamily();
+        hints.ai_socktype = SOCK_STREAM;
+
+        error = getaddrinfo(NULL, (char*) pLstnPort, &hints, &res);
+        if(error) {
+		dbgprintf("error %d querying port '%s'\n", error, pLstnPort);
+		ABORT_FINALIZE(RS_RET_INVALID_PORT);
+	}
+
+        /* Count max number of sockets we may open */
+        for(maxs = 0, r = res; r != NULL ; r = r->ai_next, maxs++)
+		/* EMPTY */;
+        pThis->socks = malloc((maxs+1) * sizeof(int));
+        if (pThis->socks == NULL) {
+               dbgprintf("couldn't allocate memory for TCP listen sockets, suspending RELP message reception.");
+               freeaddrinfo(res);
+               ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY);
+        }
+
+        *pThis->socks = 0;   /* num of sockets counter at start of array */
+        s = pThis->socks + 1;
+	for(r = res; r != NULL ; r = r->ai_next) {
+               *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
+        	if (*s < 0) {
+			if(!(r->ai_family == PF_INET6 && errno == EAFNOSUPPORT))
+				dbgprintf("creating tcp listen socket");
+				/* it is debatable if PF_INET with EAFNOSUPPORT should
+				 * also be ignored...
+				 */
+                        continue;
+                }
+
+#ifdef IPV6_V6ONLY
+                if (r->ai_family == AF_INET6) {
+                	int iOn = 1;
+			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
+			      (char *)&iOn, sizeof (iOn)) < 0) {
+			close(*s);
+			*s = -1;
+			continue;
+                	}
+                }
+#endif
+       		if(setsockopt(*s, SOL_SOCKET, SO_REUSEADDR, (char *) &on, sizeof(on)) < 0 ) {
+			dbgprintf("error %d setting tcp socket option\n", errno);
+                        close(*s);
+			*s = -1;
+			continue;
+		}
+
+		/* We use non-blocking IO! */
+		if((sockflags = fcntl(*s, F_GETFL)) != -1) {
+			sockflags |= O_NONBLOCK;
+			/* SETFL could fail too, so get it caught by the subsequent
+			 * error check.
+			 */
+			sockflags = fcntl(*s, F_SETFL, sockflags);
+		}
+		if(sockflags == -1) {
+			dbgprintf("error %d setting fcntl(O_NONBLOCK) on tcp socket", errno);
+                        close(*s);
+			*s = -1;
+			continue;
+		}
+
+
+
+		/* We need to enable BSD compatibility. Otherwise an attacker
+		 * could flood our log files by sending us tons of ICMP errors.
+		 */
+#ifndef BSD	
+		if(net.should_use_so_bsdcompat()) {
+			if (setsockopt(*s, SOL_SOCKET, SO_BSDCOMPAT,
+					(char *) &on, sizeof(on)) < 0) {
+				errmsg.LogError(NO_ERRCODE, "TCP setsockopt(BSDCOMPAT)");
+                                close(*s);
+				*s = -1;
+				continue;
+			}
+		}
+#endif
+
+	        if( (bind(*s, r->ai_addr, r->ai_addrlen) < 0)
+#ifndef IPV6_V6ONLY
+		     && (errno != EADDRINUSE)
+#endif
+	           ) {
+                        dbgprintf("error %d while binding tcp socket", errno);
+                	close(*s);
+			*s = -1;
+                        continue;
+                }
+
+		if(listen(*s,pThis->iSessMax / 10 + 5) < 0) {
+			/* If the listen fails, it most probably fails because we ask
+			 * for a too-large backlog. So in this case we first set back
+			 * to a fixed, reasonable, limit that should work. Only if
+			 * that fails, too, we give up.
+			 */
+			dbgprintf("listen with a backlog of %d failed - retrying with default of 32.",
+				    pThis->iSessMax / 10 + 5);
+			if(listen(*s, 32) < 0) {
+				dbgprintf("tcp listen error %d, suspending\n", errno);
+	                	close(*s);
+				*s = -1;
+               		        continue;
+			}
+		}
+
+		(*pThis->socks)++;
+		s++;
+	}
+
+        if(res != NULL)
+               freeaddrinfo(res);
+
+	if(*pThis->socks != maxs)
+		dbgprintf("We could initialize %d RELP TCP listen sockets out of %d we received "
+		 	"- this may or may not be an error indication.\n", *pThis->socks, maxs);
+
+        if(*pThis->socks == 0) {
+		dbgprintf("No RELP TCP listen socket could successfully be initialized, "
+			 "message reception via RELP disabled.\n");
+        	free(pThis->socks);
+		ABORT_FINALIZE(RS_RET_COULD_NOT_BIND);
+	}
+
+finalize_it:
+	RETiRet;
+}
+
+
+/* receive data from a tcp socket
+ * The lenBuf parameter must contain the max buffer size on entry and contains
+ * the number of octets read (or -1 in case of error) on exit. This function
+ * never blocks, not even when called on a blocking socket. That is important
+ * for client sockets, which are set to block during send, but should not
+ * block when trying to read data. If *pLenBuf is -1, an error occured and
+ * errno holds the exact error cause.
+ * rgerhards, 2008-03-17
+ */
+static rsRetVal
+Rcv(nsd_t *pNsd, uchar *pRcvBuf, ssize_t *pLenBuf)
+{
+	DEFiRet;
+	nsd_ptcp_t *pThis = (nsd_ptcp_t*) pNsd;
+	ISOBJ_TYPE_assert(pThis, nsd_ptcp);
+
+	*pLenBuf = recv(pThis->sock, pRcvBuf, *pLenBuf, MSG_DONTWAIT);
+
+	RETiRet;
+}
+
+
+/* send a buffer. On entry, pLenBuf contains the number of octets to
+ * write. On exit, it contains the number of octets actually written.
+ * If this number is lower than on entry, only a partial buffer has
+ * been written.
+ * rgerhards, 2008-03-19
+ */
+static rsRetVal
+Send(nsd_t *pNsd, uchar *pBuf, ssize_t *pLenBuf)
+{
+	nsd_ptcp_t *pThis = (nsd_ptcp_t*) pNsd;
+	ssize_t written;
+	DEFiRet;
+	ISOBJ_TYPE_assert(pThis, nsd_ptcp);
+
+	written = send(pThis->sock, pBuf, *pLenBuf, 0);
+
+	if(written == -1) {
+		switch(errno) {
+			case EAGAIN:
+			case EINTR:
+				/* this is fine, just retry... */
+				written = 0;
+				break;
+			default:
+				ABORT_FINALIZE(RS_RET_IO_ERROR);
+				break;
+		}
+	}
+
+	*pLenBuf = written;
+finalize_it:
+	RETiRet;
+}
+
+
+/* open a connection to a remote host (server).
+ * rgerhards, 2008-03-19
+ */
+static rsRetVal
+Connect(nsd_t *pNsd, int family, uchar *port, uchar *host)
+{
+	nsd_ptcp_t *pThis = (nsd_ptcp_t*) pNsd;
+	struct addrinfo *res = NULL;
+	struct addrinfo hints;
+
+	DEFiRet;
+	ISOBJ_TYPE_assert(pThis, nsd_ptcp);
+	assert(port != NULL);
+	assert(host != NULL);
+	assert(pThis->sock == -1);
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = family;
+	hints.ai_socktype = SOCK_STREAM;
+	if(getaddrinfo((char*)host, (char*)port, &hints, &res) != 0) {
+		dbgprintf("error %d in getaddrinfo\n", errno);
+		ABORT_FINALIZE(RS_RET_IO_ERROR);
+	}
+	
+	if((pThis->sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol)) == -1) {
+		ABORT_FINALIZE(RS_RET_IO_ERROR);
+	}
+
+	if(connect(pThis->sock, res->ai_addr, res->ai_addrlen) != 0) {
+		ABORT_FINALIZE(RS_RET_IO_ERROR);
+	}
+
+finalize_it:
+	if(res != NULL)
+               freeaddrinfo(res);
+		
+	if(iRet != RS_RET_OK) {
+		if(pThis->sock != -1) {
+			close(pThis->sock);
+			pThis->sock = -1;
+		}
+	}
+
+	RETiRet;
+}
+
+
+/* queryInterface function */
+BEGINobjQueryInterface(nsd_ptcp)
+CODESTARTobjQueryInterface(nsd_ptcp)
+	if(pIf->ifVersion != nsdCURR_IF_VERSION) {/* check for current version, increment on each change */
+		ABORT_FINALIZE(RS_RET_INTERFACE_NOT_SUPPORTED);
+	}
+
+	/* ok, we have the right interface, so let's fill it
+	 * Please note that we may also do some backwards-compatibility
+	 * work here (if we can support an older interface version - that,
+	 * of course, also affects the "if" above).
+	 */
+	pIf->Construct = (rsRetVal(*)(nsd_t**)) nsd_ptcpConstruct;
+	pIf->Destruct = (rsRetVal(*)(nsd_t**)) nsd_ptcpDestruct;
+	pIf->Abort = Abort;
+	pIf->LstnInit = LstnInit;
+	pIf->AcceptConnReq = AcceptConnReq;
+	pIf->Rcv = Rcv;
+	pIf->Send = Send;
+	pIf->Connect = Connect;
+finalize_it:
+ENDobjQueryInterface(nsd_ptcp)
+
+
+/* exit our class
+ */
+BEGINObjClassExit(nsd_ptcp, OBJ_IS_LOADABLE_MODULE) /* CHANGE class also in END MACRO! */
+CODESTARTObjClassExit(nsd_ptcp)
+	/* release objects we no longer need */
+	objRelease(net, CORE_COMPONENT);
+	objRelease(glbl, CORE_COMPONENT);
+	objRelease(errmsg, CORE_COMPONENT);
+ENDObjClassExit(nsd_ptcp)
+
+
+/* Initialize the nsd_ptcp class. Must be called as the very first method
+ * before anything else is called inside this class.
+ * rgerhards, 2008-02-19
+ */
+BEGINObjClassInit(nsd_ptcp, 1, OBJ_IS_LOADABLE_MODULE) /* class, version */
+	/* request objects we use */
+	CHKiRet(objUse(errmsg, CORE_COMPONENT));
+	CHKiRet(objUse(glbl, CORE_COMPONENT));
+	CHKiRet(objUse(net, CORE_COMPONENT));
+
+	/* set our own handlers */
+ENDObjClassInit(nsd_ptcp)
+
+
+/* --------------- here now comes the plumbing that makes as a library module --------------- */
+
+
+BEGINmodExit
+CODESTARTmodExit
+	nsd_ptcpClassExit();
+ENDmodExit
+
+
+BEGINqueryEtryPt
+CODESTARTqueryEtryPt
+CODEqueryEtryPt_STD_LIB_QUERIES
+ENDqueryEtryPt
+
+
+BEGINmodInit()
+CODESTARTmodInit
+	*ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */
+
+	/* Initialize all classes that are in our module - this includes ourselfs */
+	CHKiRet(nsd_ptcpClassInit(pModInfo)); /* must be done after tcps_sess, as we use it */
+ENDmodInit
+/* vi:set ai:
+ */