diff options
author | Michael Biebl <biebl@debian.org> | 2010-09-30 14:07:18 +0200 |
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committer | Michael Biebl <biebl@debian.org> | 2010-09-30 14:07:18 +0200 |
commit | 017fb92bd811ce1083504eafda4e2080d9520a31 (patch) | |
tree | 777a2a3627f64f6a0e2bea061c0e392af7437300 /tools/omfile.c | |
parent | dea652279a335b6d83050e5f65c45dd762901022 (diff) | |
download | rsyslog-017fb92bd811ce1083504eafda4e2080d9520a31.tar.gz |
Imported Upstream version 5.7.0upstream/5.7.0
Diffstat (limited to 'tools/omfile.c')
-rw-r--r-- | tools/omfile.c | 112 |
1 files changed, 92 insertions, 20 deletions
diff --git a/tools/omfile.c b/tools/omfile.c index 24de052..57089cf 100644 --- a/tools/omfile.c +++ b/tools/omfile.c @@ -48,10 +48,13 @@ #include <libgen.h> #include <unistd.h> #include <sys/file.h> - #ifdef OS_SOLARIS # include <fcntl.h> #endif +#ifdef HAVE_ATOMIC_BUILTINS +# include <pthread.h> +#endif + #include "conf.h" #include "syslogd-types.h" @@ -74,12 +77,37 @@ DEF_OMOD_STATIC_DATA DEFobjCurrIf(errmsg) DEFobjCurrIf(strm) +/* for our current LRU mechanism, we need a monotonically increasing counters. We use + * it much like a "Lamport logical clock": we do not need the actual time, we just need + * to know the sequence in which files were accessed. So we use a simple counter to + * create that sequence. We use an unsigned 64 bit value which is extremely unlike to + * wrap within the lifetime of a process. If we process 1,000,000 file writes per + * second, the process could still exist over 500,000 years before a wrap to 0 happens. + * That should be sufficient (and even than, there would no really bad effect ;)). + * The variable below is the global counter/clock. + */ +#if HAVE_ATOMIC_BUILTINS_64BIT +static uint64 clockFileAccess = 0; +#else +static unsigned clockFileAccess = 0; +#endif +/* and the "tick" function */ +#ifndef HAVE_ATOMIC_BUILTINS +static pthread_mutex_t mutClock; +#endif +static inline uint64 +getClockFileAccess(void) +{ + return ATOMIC_INC_AND_FETCH(&clockFileAccess, &mutClock); +} + + /* The following structure is a dynafile name cache entry. */ struct s_dynaFileCacheEntry { uchar *pName; /* name currently open, if dynamic name */ strm_t *pStrm; /* our output stream */ - time_t lastUsed; /* for LRU - last access */ + uint64 clkTickAccessed;/* for LRU - based on clockFileAccess */ }; typedef struct s_dynaFileCacheEntry dynaFileCacheEntry; @@ -89,11 +117,13 @@ typedef struct s_dynaFileCacheEntry dynaFileCacheEntry; #define USE_ASYNCWRITER_DFLT 0 /* default buffer use async writer */ #define FLUSHONTX_DFLT 1 /* default for flush on TX end */ +#define DFLT_bForceChown 0 /* globals for default values */ static int iDynaFileCacheSize = 10; /* max cache for dynamic files */ static int fCreateMode = 0644; /* mode to use when creating files */ static int fDirCreateMode = 0700; /* mode to use when creating files */ static int bFailOnChown; /* fail if chown fails? */ +static int bForceChown = DFLT_bForceChown; /* Force chown() on existing files? */ static uid_t fileUID; /* UID to be used for newly created files */ static uid_t fileGID; /* GID to be used for newly created files */ static uid_t dirUID; /* UID to be used for newly created directories */ @@ -101,7 +131,7 @@ static uid_t dirGID; /* GID to be used for newly created directories */ static int bCreateDirs = 1;/* auto-create directories for dynaFiles: 0 - no, 1 - yes */ static int bEnableSync = 0;/* enable syncing of files (no dash in front of pathname in conf): 0 - no, 1 - yes */ static int iZipLevel = 0; /* zip compression mode (0..9 as usual) */ -static bool bFlushOnTXEnd = FLUSHONTX_DFLT;/* flush write buffers when transaction has ended? */ +static sbool bFlushOnTXEnd = FLUSHONTX_DFLT;/* flush write buffers when transaction has ended? */ static int64 iIOBufSize = IOBUF_DFLT_SIZE; /* size of an io buffer */ static int iFlushInterval = FLUSH_INTRVL_DFLT; /* how often flush the output buffer on inactivity? */ static int bUseAsyncWriter = USE_ASYNCWRITER_DFLT; /* should we enable asynchronous writing? */ @@ -118,6 +148,7 @@ typedef struct _instanceData { int fDirCreateMode; /* creation mode for mkdir() */ int bCreateDirs; /* auto-create directories? */ int bSyncFile; /* should the file by sync()'ed? 1- yes, 0- no */ + sbool bForceChown; /* force chown() on existing files? */ uid_t fileUID; /* IDs for creation */ uid_t dirUID; gid_t fileGID; @@ -136,8 +167,8 @@ typedef struct _instanceData { int iZipLevel; /* zip mode to use for this selector */ int iIOBufSize; /* size of associated io buffer */ int iFlushInterval; /* how fast flush buffer on inactivity? */ - bool bFlushOnTXEnd; /* flush write buffers when transaction has ended? */ - bool bUseAsyncWriter; /* use async stream writer? */ + sbool bFlushOnTXEnd; /* flush write buffers when transaction has ended? */ + sbool bUseAsyncWriter; /* use async stream writer? */ } instanceData; @@ -163,8 +194,9 @@ CODESTARTdbgPrintInstInfo dbgprintf("\tflush interval=%d\n", pData->iFlushInterval); dbgprintf("\tfile cache size=%d\n", pData->iDynaFileCacheSize); dbgprintf("\tcreate directories: %s\n", pData->bCreateDirs ? "yes" : "no"); - dbgprintf("\tfile owner %d, group %d\n", pData->fileUID, pData->fileGID); - dbgprintf("\tdirectory owner %d, group %d\n", pData->dirUID, pData->dirGID); + dbgprintf("\tfile owner %d, group %d\n", (int) pData->fileUID, (int) pData->fileGID); + dbgprintf("\tforce chown() for all files: %s\n", pData->bForceChown ? "yes" : "no"); + dbgprintf("\tdirectory owner %d, group %d\n", (int) pData->dirUID, (int) pData->dirGID); dbgprintf("\tdir create mode 0%3.3o, file create mode 0%3.3o\n", pData->fDirCreateMode, pData->fCreateMode); dbgprintf("\tfail if owner/group can not be set: %s\n", pData->bFailOnChown ? "yes" : "no"); @@ -351,7 +383,22 @@ prepareFile(instanceData *pData, uchar *newFileName) int fd; DEFiRet; - if(access((char*)newFileName, F_OK) != 0) { + if(access((char*)newFileName, F_OK) == 0) { + if(pData->bForceChown) { + /* Try to fix wrong ownership set by someone else. Note that this code + * will no longer work once we have made the $PrivDrop code fully secure. + * This change is based on an idea of Michael Terry, provided as part of + * the effort to make rsyslogd the Ubuntu default syslogd. + * rgerhards, 2009-09-11 + */ + if(chown((char*)newFileName, pData->fileUID, pData->fileGID) != 0) { + if(pData->bFailOnChown) { + int eSave = errno; + errno = eSave; + } + } + } + } else { /* file does not exist, create it (and eventually parent directories */ fd = -1; if(pData->bCreateDirs) { @@ -372,7 +419,7 @@ prepareFile(instanceData *pData, uchar *newFileName) pData->fCreateMode); if(fd != -1) { /* check and set uid/gid */ - if(pData->fileUID != (uid_t)-1 || pData->fileGID != (gid_t) -1) { + if(pData->bForceChown || pData->fileUID != (uid_t)-1 || pData->fileGID != (gid_t) -1) { /* we need to set owner/group */ if(fchown(fd, pData->fileUID, pData->fileGID) != 0) { if(pData->bFailOnChown) { @@ -437,7 +484,7 @@ finalize_it: static inline rsRetVal prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) { - time_t ttOldest; /* timestamp of oldest element */ + uint64 ctOldest; /* "timestamp" of oldest element */ int iOldest; int i; int iFirstFree; @@ -456,7 +503,7 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) if( (pData->iCurrElt != -1) && !ustrcmp(newFileName, pCache[pData->iCurrElt]->pName)) { /* great, we are all set */ - pCache[pData->iCurrElt]->lastUsed = time(NULL); /* update timestamp for LRU */ // TODO: optimize time call! + pCache[pData->iCurrElt]->clkTickAccessed = getClockFileAccess(); // LRU needs only a strictly monotonically increasing counter, so such a one could do FINALIZE; } @@ -467,7 +514,7 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) pData->iCurrElt = -1; /* invalid current element pointer */ iFirstFree = -1; /* not yet found */ iOldest = 0; /* we assume the first element to be the oldest - that will change as we loop */ - ttOldest = time(NULL) + 1; /* there must always be an older one */ + ctOldest = getClockFileAccess(); /* there must always be an older one */ for(i = 0 ; i < pData->iCurrCacheSize ; ++i) { if(pCache[i] == NULL || pCache[i]->pName == NULL) { if(iFirstFree == -1) @@ -477,12 +524,12 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) /* we found our element! */ pData->pStrm = pCache[i]->pStrm; pData->iCurrElt = i; - pCache[i]->lastUsed = time(NULL); /* update timestamp for LRU */ + pCache[i]->clkTickAccessed = getClockFileAccess(); /* update "timestamp" for LRU */ FINALIZE; } /* did not find it - so lets keep track of the counters for LRU */ - if(pCache[i]->lastUsed < ttOldest) { - ttOldest = pCache[i]->lastUsed; + if(pCache[i]->clkTickAccessed < ctOldest) { + ctOldest = pCache[i]->clkTickAccessed; iOldest = i; } } @@ -508,7 +555,6 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) iFirstFree = pData->iCurrCacheSize++; } -// RG: this is the begin of a potential problem area /* Note that the following code sequence does not work with the cache entry itself, * but rather with pData->pStrm, the (sole) stream pointer in the non-dynafile case. * The cache array is only updated after the open was successful. -- rgerhards, 2010-03-21 @@ -546,7 +592,7 @@ prepareDynFile(instanceData *pData, uchar *newFileName, unsigned iMsgOpts) ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY); } pCache[iFirstFree]->pStrm = pData->pStrm; - pCache[iFirstFree]->lastUsed = time(NULL); + pCache[iFirstFree]->clkTickAccessed = getClockFileAccess(); pData->iCurrElt = iFirstFree; DBGPRINTF("Added new entry %d for file cache, file '%s'.\n", iFirstFree, newFileName); @@ -567,7 +613,7 @@ doWrite(instanceData *pData, uchar *pszBuf, int lenBuf) ASSERT(pData != NULL); ASSERT(pszBuf != NULL); -dbgprintf("doWrite, pData->pStrm %p, lenBuf %d\n", pData->pStrm, lenBuf); +dbgprintf("write to stream, pData->pStrm %p, lenBuf %d\n", pData->pStrm, lenBuf); if(pData->pStrm != NULL){ CHKiRet(strm.Write(pData->pStrm, pszBuf, lenBuf)); FINALIZE; @@ -633,15 +679,31 @@ BEGINtryResume CODESTARTtryResume ENDtryResume +BEGINbeginTransaction +CODESTARTbeginTransaction + /* we have nothing to do to begin a transaction */ +ENDbeginTransaction + + +BEGINendTransaction +CODESTARTendTransaction + if(pData->bFlushOnTXEnd) { + CHKiRet(strm.Flush(pData->pStrm)); + } +finalize_it: +ENDendTransaction + + BEGINdoAction CODESTARTdoAction DBGPRINTF("file to log to: %s\n", pData->f_fname); CHKiRet(writeFile(ppString, iMsgOpts, pData)); - if(pData->bFlushOnTXEnd) { - /* TODO v5: do this in endTransaction only! */ + if(!bCoreSupportsBatching && pData->bFlushOnTXEnd) { CHKiRet(strm.Flush(pData->pStrm)); } finalize_it: + if(iRet == RS_RET_OK) + iRet = RS_RET_DEFER_COMMIT; ENDdoAction @@ -724,6 +786,7 @@ CODESTARTparseSelectorAct pData->fDirCreateMode = fDirCreateMode; pData->bCreateDirs = bCreateDirs; pData->bFailOnChown = bFailOnChown; + pData->bForceChown = bForceChown; pData->fileUID = fileUID; pData->fileGID = fileGID; pData->dirUID = dirUID; @@ -759,6 +822,7 @@ static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __a dirUID = -1; dirGID = -1; bFailOnChown = 1; + bForceChown = DFLT_bForceChown; iDynaFileCacheSize = 10; fCreateMode = 0644; fDirCreateMode = 0700; @@ -796,12 +860,14 @@ CODESTARTmodExit objRelease(errmsg, CORE_COMPONENT); objRelease(strm, CORE_COMPONENT); free(pszFileDfltTplName); + DESTROY_ATOMIC_HELPER_MUT(mutClock); ENDmodExit BEGINqueryEtryPt CODESTARTqueryEtryPt CODEqueryEtryPt_STD_OMOD_QUERIES +CODEqueryEtryPt_TXIF_OMOD_QUERIES /* we support the transactional interface! */ CODEqueryEtryPt_doHUP ENDqueryEtryPt @@ -812,6 +878,11 @@ CODESTARTmodInit CODEmodInit_QueryRegCFSLineHdlr CHKiRet(objUse(errmsg, CORE_COMPONENT)); CHKiRet(objUse(strm, CORE_COMPONENT)); + + INIT_ATOMIC_HELPER_MUT(mutClock); + + INITChkCoreFeature(bCoreSupportsBatching, CORE_FEATURE_BATCHING); + DBGPRINTF("omfile: %susing transactional output interface.\n", bCoreSupportsBatching ? "" : "not "); CHKiRet(omsdRegCFSLineHdlr((uchar *)"dynafilecachesize", 0, eCmdHdlrInt, (void*) setDynaFileCacheSize, NULL, STD_LOADABLE_MODULE_ID)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"omfileziplevel", 0, eCmdHdlrInt, NULL, &iZipLevel, STD_LOADABLE_MODULE_ID)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"omfileflushinterval", 0, eCmdHdlrInt, NULL, &iFlushInterval, STD_LOADABLE_MODULE_ID)); @@ -826,6 +897,7 @@ CODEmodInit_QueryRegCFSLineHdlr CHKiRet(omsdRegCFSLineHdlr((uchar *)"filecreatemode", 0, eCmdHdlrFileCreateMode, NULL, &fCreateMode, STD_LOADABLE_MODULE_ID)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"createdirs", 0, eCmdHdlrBinary, NULL, &bCreateDirs, STD_LOADABLE_MODULE_ID)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"failonchownfailure", 0, eCmdHdlrBinary, NULL, &bFailOnChown, STD_LOADABLE_MODULE_ID)); + CHKiRet(omsdRegCFSLineHdlr((uchar *)"omfileForceChown", 0, eCmdHdlrBinary, NULL, &bForceChown, STD_LOADABLE_MODULE_ID)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"actionfileenablesync", 0, eCmdHdlrBinary, NULL, &bEnableSync, STD_LOADABLE_MODULE_ID)); CHKiRet(regCfSysLineHdlr((uchar *)"actionfiledefaulttemplate", 0, eCmdHdlrGetWord, NULL, &pszFileDfltTplName, NULL)); CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler, resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID)); |