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-rw-r--r--plugins/omprog/omprog.c357
1 files changed, 357 insertions, 0 deletions
diff --git a/plugins/omprog/omprog.c b/plugins/omprog/omprog.c
new file mode 100644
index 00000000..2a078a6d
--- /dev/null
+++ b/plugins/omprog/omprog.c
@@ -0,0 +1,357 @@
+/* omprog.c
+ * This output plugin enables rsyslog to execute a program and
+ * feed it the message stream as standard input.
+ *
+ * NOTE: read comments in module-template.h for more specifics!
+ *
+ * File begun on 2009-04-01 by RGerhards
+ *
+ * Copyright 2009 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 "rsyslog.h"
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <signal.h>
+#include <errno.h>
+#include <unistd.h>
+#include <wait.h>
+#include "dirty.h"
+#include "syslogd-types.h"
+#include "srUtils.h"
+#include "template.h"
+#include "module-template.h"
+#include "errmsg.h"
+#include "cfsysline.h"
+
+MODULE_TYPE_OUTPUT
+
+/* internal structures
+ */
+DEF_OMOD_STATIC_DATA
+DEFobjCurrIf(errmsg)
+
+typedef struct _instanceData {
+ uchar *szBinary; /* name of binary to call */
+ pid_t pid; /* pid of currently running process */
+ int fdPipe; /* file descriptor to write to */
+ int bIsRunning; /* is binary currently running? 0-no, 1-yes */
+} instanceData;
+
+/* config settings */
+static uchar *szBinary = NULL; /* name of binary to call */
+
+BEGINcreateInstance
+CODESTARTcreateInstance
+ENDcreateInstance
+
+
+BEGINisCompatibleWithFeature
+CODESTARTisCompatibleWithFeature
+ if(eFeat == sFEATURERepeatedMsgReduction)
+ iRet = RS_RET_OK;
+ENDisCompatibleWithFeature
+
+
+BEGINfreeInstance
+CODESTARTfreeInstance
+ if(pData->szBinary != NULL)
+ free(pData->szBinary);
+ENDfreeInstance
+
+
+BEGINdbgPrintInstInfo
+CODESTARTdbgPrintInstInfo
+ENDdbgPrintInstInfo
+
+
+BEGINtryResume
+CODESTARTtryResume
+ENDtryResume
+
+
+/* execute the child process (must be called in child context
+ * after fork).
+ */
+
+static void execBinary(instanceData *pData, int fdStdin)
+{
+ int i;
+ struct sigaction sigAct;
+ char *newargv[] = { NULL };
+ char *newenviron[] = { NULL };
+
+ assert(pData != NULL);
+
+ fclose(stdin);
+ dup(fdStdin);
+ //fclose(stdout);
+
+ /* we close all file handles as we fork soon
+ * Is there a better way to do this? - mail me! rgerhards@adiscon.com
+ */
+# ifndef VALGRIND /* we can not use this with valgrind - too many errors... */
+ for(i = 3 ; i <= 65535 ; ++i)
+ close(i);
+# endif
+
+ /* reset signal handlers to default */
+ memset(&sigAct, 0, sizeof(sigAct));
+ sigfillset(&sigAct.sa_mask);
+ sigAct.sa_handler = SIG_DFL;
+ for(i = 1 ; i < NSIG ; ++i)
+ sigaction(i, &sigAct, NULL);
+
+ alarm(0);
+
+ /* finally exec child */
+ execve((char*)pData->szBinary, newargv, newenviron);
+ /* switch to?
+ execlp((char*)program, (char*) program, (char*)arg, NULL);
+ */
+
+ /* we should never reach this point, but if we do, we terminate */
+ exit(1);
+}
+
+
+/* creates a pipe and starts program, uses pipe as stdin for program.
+ * rgerhards, 2009-04-01
+ */
+static rsRetVal
+openPipe(instanceData *pData)
+{
+ int pipefd[2];
+ pid_t cpid;
+ DEFiRet;
+
+ assert(pData != NULL);
+
+ if(pipe(pipefd) == -1) {
+ ABORT_FINALIZE(RS_RET_ERR_CREAT_PIPE);
+ }
+
+ DBGPRINTF("executing program '%s'\n", pData->szBinary);
+
+ /* NO OUTPUT AFTER FORK! */
+
+ cpid = fork();
+ if(cpid == -1) {
+ ABORT_FINALIZE(RS_RET_ERR_FORK);
+ }
+
+ if(cpid == 0) {
+ /* we are now the child, just set the right selectors and
+ * exec the binary. If that fails, there is not much we can do.
+ */
+ close(pipefd[1]);
+ execBinary(pData, pipefd[0]);
+ /*NO CODE HERE - WILL NEVER BE REACHED!*/
+ }
+
+ DBGPRINTF("child has pid %d\n", cpid);
+ pData->fdPipe = pipefd[1];
+ pData->pid = cpid;
+ close(pipefd[0]);
+ pData->bIsRunning = 1;
+finalize_it:
+ RETiRet;
+}
+
+
+/* clean up after a terminated child
+ */
+static inline rsRetVal
+cleanup(instanceData *pData)
+{
+ int status;
+ int ret;
+ char errStr[1024];
+ DEFiRet;
+
+ assert(pData != NULL);
+ assert(pData->bIsRunning == 1);
+RUNLOG_VAR("%d", pData->pid);
+ ret = waitpid(pData->pid, &status, 0);
+ if(ret != pData->pid) {
+ /* if waitpid() fails, we can not do much - try to ignore it... */
+ DBGPRINTF("waitpid() returned state %d[%s], future malfunction may happen\n", ret,
+ rs_strerror_r(errno, errStr, sizeof(errStr)));
+ } else {
+ /* check if we should print out some diagnostic information */
+ DBGPRINTF("waitpid status return for program '%s': %2.2x\n",
+ pData->szBinary, status);
+ if(WIFEXITED(status)) {
+ errmsg.LogError(0, NO_ERRCODE, "program '%s' exited normally, state %d",
+ pData->szBinary, WEXITSTATUS(status));
+ } else if(WIFSIGNALED(status)) {
+ errmsg.LogError(0, NO_ERRCODE, "program '%s' terminated by signal %d.",
+ pData->szBinary, WTERMSIG(status));
+ }
+ }
+
+ pData->bIsRunning = 0;
+ RETiRet;
+}
+
+
+/* try to restart the binary when it has stopped.
+ */
+static inline rsRetVal
+tryRestart(instanceData *pData)
+{
+ DEFiRet;
+ assert(pData != NULL);
+ assert(pData->bIsRunning == 0);
+
+ iRet = openPipe(pData);
+ RETiRet;
+}
+
+
+/* write to pipe
+ * note that we do not try to run block-free. If the users fears something
+ * may block (and this not be acceptable), the action should be run on its
+ * own action queue.
+ */
+static rsRetVal
+writePipe(instanceData *pData, uchar *szMsg)
+{
+ int lenWritten;
+ int lenWrite;
+ int writeOffset;
+ char errStr[1024];
+ DEFiRet;
+
+ assert(pData != NULL);
+
+ lenWrite = strlen((char*)szMsg);
+ writeOffset = 0;
+
+ do
+ {
+ lenWritten = write(pData->fdPipe, ((char*)szMsg)+writeOffset, lenWrite);
+ if(lenWritten == -1) {
+ switch(errno) {
+ case EPIPE:
+ DBGPRINTF("Program '%s' terminated, trying to restart\n",
+ pData->szBinary);
+ CHKiRet(cleanup(pData));
+ CHKiRet(tryRestart(pData));
+ break;
+ default:
+ DBGPRINTF("error %d writing to pipe: %s\n", errno,
+ rs_strerror_r(errno, errStr, sizeof(errStr)));
+ ABORT_FINALIZE(RS_RET_ERR_WRITE_PIPE);
+ break;
+ }
+ } else {
+ writeOffset += lenWritten;
+ }
+ } while(lenWritten != lenWrite);
+
+
+finalize_it:
+ RETiRet;
+}
+
+
+BEGINdoAction
+CODESTARTdoAction
+ if(pData->bIsRunning == 0) {
+ openPipe(pData);
+ }
+
+ iRet = writePipe(pData, ppString[0]);
+
+ if(iRet != RS_RET_OK)
+ iRet = RS_RET_SUSPENDED;
+ENDdoAction
+
+
+BEGINparseSelectorAct
+CODESTARTparseSelectorAct
+CODE_STD_STRING_REQUESTparseSelectorAct(1)
+ /* first check if this config line is actually for us */
+ if(strncmp((char*) p, ":omprog:", sizeof(":omprog:") - 1)) {
+ ABORT_FINALIZE(RS_RET_CONFLINE_UNPROCESSED);
+ }
+
+ /* ok, if we reach this point, we have something for us */
+ p += sizeof(":omprog:") - 1; /* eat indicator sequence (-1 because of '\0'!) */
+ CHKiRet(createInstance(&pData));
+
+ CHKmalloc(pData->szBinary = (uchar*) strdup((char*)szBinary));
+ /* check if a non-standard template is to be applied */
+ if(*(p-1) == ';')
+ --p;
+ CHKiRet(cflineParseTemplateName(&p, *ppOMSR, 0, 0, (uchar*) "RSYSLOG_FileFormat"));
+CODE_STD_FINALIZERparseSelectorAct
+ENDparseSelectorAct
+
+
+BEGINmodExit
+CODESTARTmodExit
+ if(szBinary != NULL) {
+ free(szBinary);
+ szBinary = NULL;
+ }
+ CHKiRet(objRelease(errmsg, CORE_COMPONENT));
+finalize_it:
+ENDmodExit
+
+
+BEGINqueryEtryPt
+CODESTARTqueryEtryPt
+CODEqueryEtryPt_STD_OMOD_QUERIES
+ENDqueryEtryPt
+
+
+
+/* Reset config variables for this module to default values.
+ */
+static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __attribute__((unused)) *pVal)
+{
+ DEFiRet;
+
+ if(szBinary != NULL) {
+ free(szBinary);
+ szBinary = NULL;
+ }
+
+ RETiRet;
+}
+
+
+BEGINmodInit()
+CODESTARTmodInit
+ *ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */
+CODEmodInit_QueryRegCFSLineHdlr
+ CHKiRet(objUse(errmsg, CORE_COMPONENT));
+ CHKiRet(omsdRegCFSLineHdlr((uchar *)"actionomprogbinary", 0, eCmdHdlrGetWord, NULL, &szBinary, STD_LOADABLE_MODULE_ID));
+ CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler, resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID));
+CODEmodInit_QueryRegCFSLineHdlr
+ENDmodInit
+
+/* vi:set ai:
+ */