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Diffstat (limited to 'runtime/netstrm.c')
| -rw-r--r-- | runtime/netstrm.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/runtime/netstrm.c b/runtime/netstrm.c new file mode 100644 index 00000000..274a92d7 --- /dev/null +++ b/runtime/netstrm.c @@ -0,0 +1,344 @@ +/* netstrmstrm.c + * + * This class implements a generic netstrmwork stream class. It supports + * sending and receiving data streams over a netstrmwork. The class abstracts + * the transport, though it is a safe assumption that TCP is being used. + * The class has a number of properties, among which are also ones to + * select privacy settings, eg by enabling TLS and/or GSSAPI. In the + * long run, this class shall provide all stream-oriented netstrmwork + * functionality inside rsyslog. + * + * It is a high-level class, which uses a number of helper objects + * to carry out its work (including, and most importantly, transport + * drivers). + * + * Work on this module begun 2008-04-17 by Rainer Gerhards. This code + * borrows from librelp's tcp.c/.h code. librelp is dual licensed and + * Rainer Gerhards and Adiscon GmbH have agreed to permit using the code + * under the terms of the GNU Lesser General Public License. + * + * 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.h" +#include "netstrm.h" + +MODULE_TYPE_LIB + +/* static data */ +DEFobjStaticHelpers +DEFobjCurrIf(errmsg) +DEFobjCurrIf(glbl) +DEFobjCurrIf(net) + + +/* load our low-level driver. This must be done before any + * driver-specific functions (allmost all...) can be carried + * out. Note that the driver's .ifIsLoaded is correctly + * initialized by calloc() and we depend on that. + * rgerhards, 2008-04-18 + */ +static rsRetVal +loadDrvr(netstrm_t *pThis) +{ + uchar *pDrvrName; + DEFiRet; + + pDrvrName = pThis->pDrvrName; + if(pDrvrName == NULL) /* if no drvr name is set, use system default */ + pDrvrName = glbl.GetDfltNetstrmDrvr(); + + pThis->Drvr.ifVersion = nsdCURR_IF_VERSION; + /* The pDrvrName+2 below is a hack to obtain the object name. It + * safes us to have yet another variable with the name without "lm" in + * front of it. If we change the module load interface, we may re-think + * about this hack, but for the time being it is efficient and clean + * enough. -- rgerhards, 2008-04-18 + */ + CHKiRet(obj.UseObj(__FILE__, pDrvrName+2, pDrvrName, (void*) &pThis->Drvr)); +finalize_it: + RETiRet; +} + + +/* Standard-Constructor */ +BEGINobjConstruct(netstrm) /* be sure to specify the object type also in END macro! */ +ENDobjConstruct(netstrm) + + +/* destructor for the netstrm object */ +BEGINobjDestruct(netstrm) /* be sure to specify the object type also in END and CODESTART macros! */ +CODESTARTobjDestruct(netstrm) + if(pThis->pDrvrData != NULL) + iRet = pThis->Drvr.Destruct(&pThis->pDrvrData); +ENDobjDestruct(netstrm) + + +/* ConstructionFinalizer */ +static rsRetVal +netstrmConstructFinalize(netstrm_t *pThis) +{ + DEFiRet; + ISOBJ_TYPE_assert(pThis, netstrm); + CHKiRet(loadDrvr(pThis)); + CHKiRet(pThis->Drvr.Construct(&pThis->pDrvrData)); +finalize_it: + RETiRet; +} + +/* abort a connection. This is much like Destruct(), but tries + * to discard any unsent data. -- rgerhards, 2008-03-24 + */ +static rsRetVal +AbortDestruct(netstrm_t **ppThis) +{ + DEFiRet; + assert(ppThis != NULL); + ISOBJ_TYPE_assert((*ppThis), netstrm); + + /* we do NOT exit on error, because that would make things worse */ + (*ppThis)->Drvr.Abort((*ppThis)->pDrvrData); + iRet = netstrmDestruct(ppThis); + + RETiRet; +} + + +#if 0 +This is not yet working - wait until we arrive at the receiver side (distracts too much at the moment) + +/* accept an incoming connection request, pNsdLstn provides the "listen socket" on which we can + * accept the new session. + * rgerhards, 2008-03-17 + */ +static rsRetVal +AcceptConnReq(netstrm_t **ppThis, nsd_t *pNsdLstn) +{ + netstrm_t *pThis = NULL; + nsd_t *pNsd; + DEFiRet; + + assert(ppThis != NULL); + + /* construct our object so that we can use it... */ + CHKiRet(netstrmConstruct(&pThis)); + + /* TODO: obtain hostname, normalize (callback?), save it */ + 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 = pThis; + +finalize_it: + if(iRet != RS_RET_OK) { + if(pThis != NULL) + netstrmDestruct(&pThis); + /* the close may be redundant, but that doesn't hurt... */ + if(iNewSock >= 0) + close(iNewSock); + } + + RETiRet; +} +#endif + + +/* 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(netstrm_t *pThis, uchar *pLstnPort) +{ + DEFiRet; + ISOBJ_TYPE_assert(pThis, netstrm); + assert(pLstnPort != NULL); + CHKiRet(pThis->Drvr.LstnInit(pThis->pDrvrData, pLstnPort)); + +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(netstrm_t *pThis, uchar *pBuf, ssize_t *pLenBuf) +{ + DEFiRet; + ISOBJ_TYPE_assert(pThis, netstrm); + iRet = pThis->Drvr.Rcv(pThis->pDrvrData, pBuf, pLenBuf); + 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(netstrm_t *pThis, uchar *pBuf, ssize_t *pLenBuf) +{ + DEFiRet; + ISOBJ_TYPE_assert(pThis, netstrm); + iRet = pThis->Drvr.Send(pThis->pDrvrData, pBuf, pLenBuf); + RETiRet; +} + + +/* open a connection to a remote host (server). + * rgerhards, 2008-03-19 + */ +static rsRetVal +Connect(netstrm_t *pThis, int family, uchar *port, uchar *host) +{ + DEFiRet; + ISOBJ_TYPE_assert(pThis, netstrm); + assert(port != NULL); + assert(host != NULL); + iRet = pThis->Drvr.Connect(pThis->pDrvrData, family, port, host); + RETiRet; +} + + +/* queryInterface function + */ +BEGINobjQueryInterface(netstrm) +CODESTARTobjQueryInterface(netstrm) + if(pIf->ifVersion != netstrmCURR_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 = netstrmConstruct; + pIf->ConstructFinalize = netstrmConstructFinalize; + pIf->Destruct = netstrmDestruct; + pIf->AbortDestruct = AbortDestruct; + pIf->LstnInit = LstnInit; + // TODO: add later: pIf->AcceptConnReq = AcceptConnReq; + pIf->Rcv = Rcv; + pIf->Send = Send; + pIf->Connect = Connect; +finalize_it: +ENDobjQueryInterface(netstrm) + + +/* exit our class + */ +BEGINObjClassExit(netstrm, OBJ_IS_LOADABLE_MODULE) /* CHANGE class also in END MACRO! */ +CODESTARTObjClassExit(netstrm) + /* release objects we no longer need */ + objRelease(net, CORE_COMPONENT); + objRelease(glbl, CORE_COMPONENT); + objRelease(errmsg, CORE_COMPONENT); +ENDObjClassExit(netstrm) + + +/* Initialize the netstrm class. Must be called as the very first method + * before anything else is called inside this class. + * rgerhards, 2008-02-19 + */ +BEGINAbstractObjClassInit(netstrm, 1, OBJ_IS_CORE_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(netstrm) + + +/* --------------- here now comes the plumbing that makes as a library module --------------- */ + + +BEGINmodExit +CODESTARTmodExit + netstrmClassExit(); +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(netstrmClassInit(pModInfo)); /* must be done after tcps_sess, as we use it */ +ENDmodInit +/* vi:set ai: + */ |