1 files changed, 317 insertions, 0 deletions
diff --git a/runtime/nsdsel_gtls.c b/runtime/nsdsel_gtls.c
new file mode 100644
index 0000000..01cfb05
--- /dev/null
+++ b/runtime/nsdsel_gtls.c
@@ -0,0 +1,317 @@
+/* nsdsel_gtls.c
+ *
+ * An implementation of the nsd select() interface for GnuTLS.
+ *
+ * Copyright (C) 2008-2016 Adiscon GmbH.
+ *
+ * This file is part of the rsyslog runtime library.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *       -or-
+ *       see COPYING.ASL20 in the source distribution
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "config.h"
+
+#include <stdlib.h>
+#include <assert.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/select.h>
+#include <gnutls/gnutls.h>
+
+#include "rsyslog.h"
+#include "module-template.h"
+#include "obj.h"
+#include "errmsg.h"
+#include "nsd.h"
+#include "nsd_gtls.h"
+#include "nsd_ptcp.h"
+#include "nsdsel_ptcp.h"
+#include "nsdsel_gtls.h"
+
+/* static data */
+DEFobjStaticHelpers
+DEFobjCurrIf(glbl)
+DEFobjCurrIf(nsdsel_ptcp)
+
+static rsRetVal
+gtlsHasRcvInBuffer(nsd_gtls_t *pThis)
+{
+	/* we have a valid receive buffer one such is allocated and
+	 * NOT exhausted!
+	 */
+	DBGPRINTF("hasRcvInBuffer on nsd %p: pszRcvBuf %p, lenRcvBuf %d\n", pThis,
+		pThis->pszRcvBuf, pThis->lenRcvBuf);
+	return(pThis->pszRcvBuf != NULL && pThis->lenRcvBuf != -1);
+	}
+
+
+/* Standard-Constructor
+ */
+BEGINobjConstruct(nsdsel_gtls) /* be sure to specify the object type also in END macro! */
+	iRet = nsdsel_ptcp.Construct(&pThis->pTcp);
+ENDobjConstruct(nsdsel_gtls)
+
+
+/* destructor for the nsdsel_gtls object */
+BEGINobjDestruct(nsdsel_gtls) /* be sure to specify the object type also in END and CODESTART macros! */
+CODESTARTobjDestruct(nsdsel_gtls)
+	if(pThis->pTcp != NULL)
+		nsdsel_ptcp.Destruct(&pThis->pTcp);
+ENDobjDestruct(nsdsel_gtls)
+
+
+/* Add a socket to the select set */
+static rsRetVal
+Add(nsdsel_t *pNsdsel, nsd_t *pNsd, nsdsel_waitOp_t waitOp)
+{
+	DEFiRet;
+	nsdsel_gtls_t *pThis = (nsdsel_gtls_t*) pNsdsel;
+	nsd_gtls_t *pNsdGTLS = (nsd_gtls_t*) pNsd;
+
+	ISOBJ_TYPE_assert(pThis, nsdsel_gtls);
+	ISOBJ_TYPE_assert(pNsdGTLS, nsd_gtls);
+	DBGPRINTF("Add on nsd %p:\n", pNsdGTLS);
+	if(pNsdGTLS->iMode == 1) {
+		if(waitOp == NSDSEL_RD && gtlsHasRcvInBuffer(pNsdGTLS)) {
+			++pThis->iBufferRcvReady;
+			dbgprintf("nsdsel_gtls: data already present in buffer, initiating "
+				  "dummy select %p->iBufferRcvReady=%d\n",
+				  pThis, pThis->iBufferRcvReady);
+			FINALIZE;
+		}
+		if(pNsdGTLS->rtryCall != gtlsRtry_None) {
+			if(gnutls_record_get_direction(pNsdGTLS->sess) == 0) {
+				CHKiRet(nsdsel_ptcp.Add(pThis->pTcp, pNsdGTLS->pTcp, NSDSEL_RD));
+			} else {
+				CHKiRet(nsdsel_ptcp.Add(pThis->pTcp, pNsdGTLS->pTcp, NSDSEL_WR));
+			}
+			FINALIZE;
+		}
+	}
+
+	dbgprintf("nsdsel_gtls: reached end on nsd %p, calling nsdsel_ptcp.Add with waitOp %d... \n", pNsdGTLS, waitOp);
+	/* if we reach this point, we need no special handling */
+	CHKiRet(nsdsel_ptcp.Add(pThis->pTcp, pNsdGTLS->pTcp, waitOp));
+
+finalize_it:
+	RETiRet;
+}
+
+
+/* perform the select()  piNumReady returns how many descriptors are ready for IO
+ * TODO: add timeout!
+ */
+static rsRetVal
+Select(nsdsel_t *pNsdsel, int *piNumReady)
+{
+	DEFiRet;
+	nsdsel_gtls_t *pThis = (nsdsel_gtls_t*) pNsdsel;
+
+	ISOBJ_TYPE_assert(pThis, nsdsel_gtls);
+	if(pThis->iBufferRcvReady > 0) {
+		/* we still have data ready! */
+		*piNumReady = pThis->iBufferRcvReady;
+		dbgprintf("nsdsel_gtls: doing dummy select for %p->iBufferRcvReady=%d, data present\n",
+			pThis, pThis->iBufferRcvReady);
+	} else {
+		iRet = nsdsel_ptcp.Select(pThis->pTcp, piNumReady);
+	}
+
+	RETiRet;
+}
+
+
+/* retry an interrupted GTLS operation
+ * rgerhards, 2008-04-30
+ */
+static rsRetVal
+doRetry(nsd_gtls_t *pNsd)
+{
+	DEFiRet;
+	int gnuRet;
+
+	dbgprintf("doRetry: GnuTLS requested retry of %d operation - executing\n", pNsd->rtryCall);
+
+	/* We follow a common scheme here: first, we do the systen call and
+	 * then we check the result. So far, the result is checked after the
+	 * switch, because the result check is the same for all calls. Note that
+	 * this may change once we deal with the read and write calls (but
+	 * probably this becomes an issue only when we begin to work on TLS
+	 * for relp). -- rgerhards, 2008-04-30
+	 */
+	switch(pNsd->rtryCall) {
+		case gtlsRtry_handshake:
+			gnuRet = gnutls_handshake(pNsd->sess);
+			if(gnuRet == GNUTLS_E_AGAIN || gnuRet == GNUTLS_E_INTERRUPTED) {
+				dbgprintf("doRetry: GnuTLS handshake retry did not finish - "
+					"setting to retry (this is OK and can happen)\n");
+				FINALIZE;
+			} else if(gnuRet == 0) {
+				pNsd->rtryCall = gtlsRtry_None; /* we are done */
+				/* we got a handshake, now check authorization */
+				CHKiRet(gtlsChkPeerAuth(pNsd));
+			} else {
+				uchar *pGnuErr = gtlsStrerror(gnuRet);
+				LogError(0, RS_RET_TLS_HANDSHAKE_ERR,
+					"GnuTLS handshake retry returned error: %s\n", pGnuErr);
+				free(pGnuErr);
+				ABORT_FINALIZE(RS_RET_TLS_HANDSHAKE_ERR);
+			}
+			break;
+		case gtlsRtry_recv:
+			dbgprintf("doRetry: retrying gtls recv, nsd: %p\n", pNsd);
+			iRet = gtlsRecordRecv(pNsd);
+			if (iRet == RS_RET_RETRY) {
+				// Check if there is pending data
+				size_t stBytesLeft = gnutls_record_check_pending(pNsd->sess);
+				if (stBytesLeft > 0) {
+					// We are in retry and more data waiting, finalize it
+					goto finalize_it;
+				} else {
+					dbgprintf("doRetry: gtlsRecordRecv returned RETRY, but there is no pending"
+						"data on nsd: %p\n", pNsd);
+				}
+			}
+			pNsd->rtryCall = gtlsRtry_None; /* no more data, we are done */
+			gnuRet = 0;
+			break;
+		case gtlsRtry_None:
+		default:
+			assert(0); /* this shall not happen! */
+			dbgprintf("ERROR: pNsd->rtryCall invalid in nsdsel_gtls.c:%d\n", __LINE__);
+			gnuRet = 0; /* if it happens, we have at least a defined behaviour... ;) */
+			break;
+	}
+
+	if(gnuRet == 0) {
+		pNsd->rtryCall = gtlsRtry_None; /* we are done */
+	} else if(gnuRet != GNUTLS_E_AGAIN && gnuRet != GNUTLS_E_INTERRUPTED) {
+		uchar *pErr = gtlsStrerror(gnuRet);
+		LogError(0, RS_RET_GNUTLS_ERR, "unexpected GnuTLS error %d in %s:%d: %s\n",
+		gnuRet, __FILE__, __LINE__, pErr); \
+		free(pErr);
+		pNsd->rtryCall = gtlsRtry_None; /* we are also done... ;) */
+		ABORT_FINALIZE(RS_RET_GNUTLS_ERR);
+	}
+	/* if we are interrupted once again (else case), we do not need to
+	 * change our status because we are already setup for retries.
+	 */
+
+finalize_it:
+	if(iRet != RS_RET_OK && iRet != RS_RET_CLOSED && iRet != RS_RET_RETRY)
+		pNsd->bAbortConn = 1; /* request abort */
+	RETiRet;
+}
+
+
+/* check if a socket is ready for IO */
+static rsRetVal
+IsReady(nsdsel_t *pNsdsel, nsd_t *pNsd, nsdsel_waitOp_t waitOp, int *pbIsReady)
+{
+	DEFiRet;
+	nsdsel_gtls_t *pThis = (nsdsel_gtls_t*) pNsdsel;
+	nsd_gtls_t *pNsdGTLS = (nsd_gtls_t*) pNsd;
+
+	ISOBJ_TYPE_assert(pThis, nsdsel_gtls);
+	ISOBJ_TYPE_assert(pNsdGTLS, nsd_gtls);
+	if(pNsdGTLS->iMode == 1) {
+		if(waitOp == NSDSEL_RD && gtlsHasRcvInBuffer(pNsdGTLS)) {
+			*pbIsReady = 1;
+			--pThis->iBufferRcvReady; /* one "pseudo-read" less */
+			dbgprintf("nsdl_gtls: dummy read, decermenting %p->iBufRcvReady, now %d\n",
+				   pThis, pThis->iBufferRcvReady);
+			FINALIZE;
+		}
+		if(pNsdGTLS->rtryCall == gtlsRtry_handshake) {
+			CHKiRet(doRetry(pNsdGTLS));
+			/* we used this up for our own internal processing, so the socket
+			 * is not ready from the upper layer point of view.
+			 */
+			*pbIsReady = 0;
+			FINALIZE;
+		}
+		else if(pNsdGTLS->rtryCall == gtlsRtry_recv) {
+			iRet = doRetry(pNsdGTLS);
+			if(iRet == RS_RET_OK) {
+				*pbIsReady = 0;
+				FINALIZE;
+			}
+		}
+
+		/* now we must ensure that we do not fall back to PTCP if we have
+		 * done a "dummy" select. In that case, we know when the predicate
+		 * is not matched here, we do not have data available for this
+		 * socket. -- rgerhards, 2010-11-20
+		 */
+		if(pThis->iBufferRcvReady) {
+			dbgprintf("nsd_gtls: dummy read, %p->buffer not available for this FD\n", pThis);
+			*pbIsReady = 0;
+			FINALIZE;
+		}
+	}
+
+	CHKiRet(nsdsel_ptcp.IsReady(pThis->pTcp, pNsdGTLS->pTcp, waitOp, pbIsReady));
+
+finalize_it:
+	RETiRet;
+}
+
+
+/* ------------------------------ end support for the select() interface ------------------------------ */
+
+
+/* queryInterface function */
+BEGINobjQueryInterface(nsdsel_gtls)
+CODESTARTobjQueryInterface(nsdsel_gtls)
+	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(*)(nsdsel_t**)) nsdsel_gtlsConstruct;
+	pIf->Destruct = (rsRetVal(*)(nsdsel_t**)) nsdsel_gtlsDestruct;
+	pIf->Add = Add;
+	pIf->Select = Select;
+	pIf->IsReady = IsReady;
+finalize_it:
+ENDobjQueryInterface(nsdsel_gtls)
+
+
+/* exit our class
+ */
+BEGINObjClassExit(nsdsel_gtls, OBJ_IS_CORE_MODULE) /* CHANGE class also in END MACRO! */
+CODESTARTObjClassExit(nsdsel_gtls)
+	/* release objects we no longer need */
+	objRelease(glbl, CORE_COMPONENT);
+	objRelease(nsdsel_ptcp, LM_NSD_PTCP_FILENAME);
+ENDObjClassExit(nsdsel_gtls)
+
+
+/* Initialize the nsdsel_gtls class. Must be called as the very first method
+ * before anything else is called inside this class.
+ * rgerhards, 2008-02-19
+ */
+BEGINObjClassInit(nsdsel_gtls, 1, OBJ_IS_CORE_MODULE) /* class, version */
+	/* request objects we use */
+	CHKiRet(objUse(glbl, CORE_COMPONENT));
+	CHKiRet(objUse(nsdsel_ptcp, LM_NSD_PTCP_FILENAME));
+
+	/* set our own handlers */
+ENDObjClassInit(nsdsel_gtls)
+/* vi:set ai:
+ */