From d0a73d3449511392b115ca078517ff659aafe23d Mon Sep 17 00:00:00 2001 From: Rainer Gerhards Date: Wed, 11 Apr 2012 11:18:41 +0200 Subject: bugfix: hostname was not requeried on HUP Thanks to Marius Tomaschewski for reporting this bug. --- tools/syslogd.c | 165 +++++++++++++++++++++++++++++++------------------------- 1 file changed, 93 insertions(+), 72 deletions(-) (limited to 'tools') diff --git a/tools/syslogd.c b/tools/syslogd.c index 0b7bbc96..183decb1 100644 --- a/tools/syslogd.c +++ b/tools/syslogd.c @@ -154,6 +154,7 @@ DEFobjCurrIf(net) /* TODO: make go away! */ /* forward definitions */ static rsRetVal GlobalClassExit(void); +static rsRetVal queryLocalHostname(void); #ifndef _PATH_LOGCONF @@ -1897,6 +1898,11 @@ DEFFUNC_llExecFunc(doHUPActions) * is *NOT* the sighup handler. The signal is recorded by the handler, that record * detected inside the mainloop and then this function is called to do the * real work. -- rgerhards, 2008-10-22 + * Note: there is a VERY slim chance of a data race when the hostname is reset. + * We prefer to take this risk rather than sync all accesses, because to the best + * of my analysis it can not really hurt (the actual property is reference-counted) + * but the sync would require some extra CPU for *each* message processed. + * rgerhards, 2012-04-11 */ static inline void doHUP(void) @@ -1912,6 +1918,7 @@ doHUP(void) logmsgInternal(NO_ERRCODE, LOG_SYSLOG|LOG_INFO, (uchar*)buf, 0); } + queryLocalHostname(); /* re-read our name */ ruleset.IterateAllActions(doHUPActions, NULL); } @@ -2329,6 +2336,90 @@ GlobalClassExit(void) } +/* query our host and domain names - we need to do this early as we may emit + * rgerhards, 2012-04-11 + */ +static rsRetVal +queryLocalHostname(void) +{ + uchar *LocalHostName; + uchar *LocalDomain; + uchar *LocalFQDNName; + uchar *p; + struct hostent *hent; + DEFiRet; + + net.getLocalHostname(&LocalFQDNName); + CHKmalloc(LocalHostName = (uchar*) strdup((char*)LocalFQDNName)); + glbl.SetLocalFQDNName(LocalFQDNName); /* set the FQDN before we modify it */ + if((p = (uchar*)strchr((char*)LocalHostName, '.'))) { + *p++ = '\0'; + LocalDomain = p; + } else { + LocalDomain = (uchar*)""; + + /* It's not clearly defined whether gethostname() + * should return the simple hostname or the fqdn. A + * good piece of software should be aware of both and + * we want to distribute good software. Joey + * + * Good software also always checks its return values... + * If syslogd starts up before DNS is up & /etc/hosts + * doesn't have LocalHostName listed, gethostbyname will + * return NULL. + */ + /* TODO: gethostbyname() is not thread-safe, but replacing it is + * not urgent as we do not run on multiple threads here. rgerhards, 2007-09-25 + */ + hent = gethostbyname((char*)LocalHostName); + if(hent) { + int i = 0; + + if(hent->h_aliases) { + size_t hnlen; + + hnlen = strlen((char *) LocalHostName); + + for (i = 0; hent->h_aliases[i]; i++) { + if (!strncmp(hent->h_aliases[i], (char *) LocalHostName, hnlen) + && hent->h_aliases[i][hnlen] == '.') { + /* found a matching hostname */ + break; + } + } + } + + free(LocalHostName); + if(hent->h_aliases && hent->h_aliases[i]) { + CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_aliases[i])); + } else { + CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_name)); + } + + if((p = (uchar*)strchr((char*)LocalHostName, '.'))) + { + *p++ = '\0'; + LocalDomain = p; + } + } + } + + /* Convert to lower case to recognize the correct domain laterly */ + for(p = LocalDomain ; *p ; p++) + *p = (char)tolower((int)*p); + + /* we now have our hostname and can set it inside the global vars. + * TODO: think if all of this would better be a runtime function + * rgerhards, 2008-04-17 + */ + glbl.SetLocalHostName(LocalHostName); + glbl.SetLocalDomain(LocalDomain); + glbl.GenerateLocalHostNameProperty(); /* must be redone after conf processing, FQDN setting may have changed */ +finalize_it: + RETiRet; +} + + /* some support for command line option parsing. Any non-trivial options must be * buffered until the complete command line has been parsed. This is necessary to * prevent dependencies between the options. That, in turn, means we need to have @@ -2530,9 +2621,7 @@ int realMain(int argc, char **argv) { DEFiRet; - register uchar *p; int ch; - struct hostent *hent; extern int optind; extern char *optarg; int bEOptionWasGiven = 0; @@ -2541,9 +2630,6 @@ int realMain(int argc, char **argv) int bChDirRoot = 1; /* change the current working directory to "/"? */ char *arg; /* for command line option processing */ uchar legacyConfLine[80]; - uchar *LocalHostName; - uchar *LocalDomain; - uchar *LocalFQDNName; char cwdbuf[128]; /* buffer to obtain/display current working directory */ /* first, parse the command line options. We do not carry out any actual work, just @@ -2651,7 +2737,7 @@ int realMain(int argc, char **argv) /* we need to create the inputName property (only once during our lifetime) */ CHKiRet(prop.Construct(&pInternalInputName)); - CHKiRet(prop.SetString(pInternalInputName, UCHAR_CONSTANT("rsyslogd"), sizeof("rsyslgod") - 1)); + CHKiRet(prop.SetString(pInternalInputName, UCHAR_CONSTANT("rsyslogd"), sizeof("rsyslogd") - 1)); CHKiRet(prop.ConstructFinalize(pInternalInputName)); CHKiRet(prop.Construct(&pLocalHostIP)); @@ -2661,72 +2747,7 @@ int realMain(int argc, char **argv) /* get our host and domain names - we need to do this early as we may emit * error log messages, which need the correct hostname. -- rgerhards, 2008-04-04 */ - net.getLocalHostname(&LocalFQDNName); - CHKmalloc(LocalHostName = (uchar*) strdup((char*)LocalFQDNName)); - glbl.SetLocalFQDNName(LocalFQDNName); /* set the FQDN before we modify it */ - if((p = (uchar*)strchr((char*)LocalHostName, '.'))) { - *p++ = '\0'; - LocalDomain = p; - } else { - LocalDomain = (uchar*)""; - - /* It's not clearly defined whether gethostname() - * should return the simple hostname or the fqdn. A - * good piece of software should be aware of both and - * we want to distribute good software. Joey - * - * Good software also always checks its return values... - * If syslogd starts up before DNS is up & /etc/hosts - * doesn't have LocalHostName listed, gethostbyname will - * return NULL. - */ - /* TODO: gethostbyname() is not thread-safe, but replacing it is - * not urgent as we do not run on multiple threads here. rgerhards, 2007-09-25 - */ - hent = gethostbyname((char*)LocalHostName); - if(hent) { - int i = 0; - - if(hent->h_aliases) { - size_t hnlen; - - hnlen = strlen((char *) LocalHostName); - - for (i = 0; hent->h_aliases[i]; i++) { - if (!strncmp(hent->h_aliases[i], (char *) LocalHostName, hnlen) - && hent->h_aliases[i][hnlen] == '.') { - /* found a matching hostname */ - break; - } - } - } - - free(LocalHostName); - if(hent->h_aliases && hent->h_aliases[i]) { - CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_aliases[i])); - } else { - CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_name)); - } - - if((p = (uchar*)strchr((char*)LocalHostName, '.'))) - { - *p++ = '\0'; - LocalDomain = p; - } - } - } - - /* Convert to lower case to recognize the correct domain laterly */ - for(p = LocalDomain ; *p ; p++) - *p = (char)tolower((int)*p); - - /* we now have our hostname and can set it inside the global vars. - * TODO: think if all of this would better be a runtime function - * rgerhards, 2008-04-17 - */ - glbl.SetLocalHostName(LocalHostName); - glbl.SetLocalDomain(LocalDomain); - glbl.GenerateLocalHostNameProperty(); /* must be redone after conf processing, FQDN setting may have changed */ + queryLocalHostname(); /* initialize the objects */ if((iRet = modInitIminternal()) != RS_RET_OK) { -- cgit From a3a0acadb4aa9d09bde3a6951557939b0a0eeda6 Mon Sep 17 00:00:00 2001 From: Marius Tomaschewski Date: Wed, 11 Apr 2012 14:39:42 +0200 Subject: Allocate LocalDomain as new string LocalDomain points to "" or the domain in LocalHostName, allocate as new string before passing to SetLocalDomain or free will fail later. Signed-off-by: Marius Tomaschewski --- tools/syslogd.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools') diff --git a/tools/syslogd.c b/tools/syslogd.c index 183decb1..5e94beab 100644 --- a/tools/syslogd.c +++ b/tools/syslogd.c @@ -2404,6 +2404,9 @@ queryLocalHostname(void) } } + /* LocalDomain is "" or part of LocalHostName, allocate a new string */ + CHKmalloc(LocalDomain = (uchar*)strdup(LocalDomain)); + /* Convert to lower case to recognize the correct domain laterly */ for(p = LocalDomain ; *p ; p++) *p = (char)tolower((int)*p); -- cgit From d749dadcc30e35448894a152fb0ddf77d60b8300 Mon Sep 17 00:00:00 2001 From: Rainer Gerhards Date: Thu, 12 Apr 2012 10:14:32 +0200 Subject: imuxsock: do not cache hostname --- tools/syslogd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/syslogd.c b/tools/syslogd.c index 5e94beab..af63b111 100644 --- a/tools/syslogd.c +++ b/tools/syslogd.c @@ -21,7 +21,7 @@ * For further information, please see http://www.rsyslog.com * * rsyslog - An Enhanced syslogd Replacement. - * Copyright 2003-2009 Rainer Gerhards and Adiscon GmbH. + * Copyright 2003-2012 Rainer Gerhards and Adiscon GmbH. * * This file is part of rsyslog. * -- cgit