removed dependency on MAXHOSTNAMELEN as much as it made sense.

GNU/Hurd does not define it (because it has no limit), and we have taken
care for cases where it is undefined now. However, some very few places
remain where IMHO it currently is not worth fixing the code. If it is
not defined, we have used a generous value of 1K, which is above IETF
RFC's on hostname length at all. The memory consumption is no issue, as
there are only a handful of this buffers allocated *per run* -- that's
also the main reason why we consider it not worth to be fixed any further.

9 files changed, 104 insertions, 25 deletions

diff --git a/ChangeLog b/ChangeLog
index b207a979..551b7278 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
 ---------------------------------------------------------------------------
 Version 3.17.1 (rgerhards), 2008-04-??
+- removed dependency on MAXHOSTNAMELEN as much as it made sense.
+  GNU/Hurd does not define it (because it has no limit), and we have taken
+  care for cases where it is undefined now. However, some very few places
+  remain where IMHO it currently is not worth fixing the code. If it is
+  not defined, we have used a generous value of 1K, which is above IETF
+  RFC's on hostname length at all. The memory consumption is no issue, as
+  there are only a handful of this buffers allocated *per run* -- that's
+  also the main reason why we consider it not worth to be fixed any further.
 ---------------------------------------------------------------------------
 Version 3.17.0 (rgerhards), 2008-04-08
 - added native ability to send mail messages
diff --git a/configure.ac b/configure.ac
index 1516ef71..4f3459c3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -83,6 +83,22 @@ AC_FUNC_STRERROR_R
 AC_FUNC_VPRINTF
 AC_CHECK_FUNCS([flock basename alarm clock_gettime gethostbyname gethostname gettimeofday localtime_r memset mkdir regcomp select setid socket strcasecmp strchr strdup strerror strndup strnlen strrchr strstr strtol strtoul uname ttyname_r])
 
+# Check for MAXHOSTNAMELEN
+AC_MSG_CHECKING(for MAXHOSTNAMELEN)
+AC_TRY_COMPILE([
+	#include <sys/param.h>
+	], [
+	return MAXHOSTNAMELEN;
+	]
+	,
+	AC_MSG_RESULT(yes)
+	,
+	# note: we use 1024 here, which should be far more than needed by any system. If that's too low, we simply
+	# life with the need to change it. Most of the code doesn't need it anyways, but there are a few places 
+	# where it actually is needed and it makes no sense to change them.
+	AC_DEFINE(MAXHOSTNAMELEN, 1024, [Define with a value if your <sys/param.h> does not define MAXHOSTNAMELEN])
+	AC_MSG_RESULT(no; defined as 64)
+)
 
 # Large file support
 AC_ARG_ENABLE(largefile,
diff --git a/net.c b/net.c
index ab669323..43e13eb3 100644
--- a/net.c
+++ b/net.c
@@ -852,6 +852,44 @@ finalize_it:
 }
 
 
+/* get the name of the local host. A pointer to a character pointer is passed
+ * in, which on exit points to the local hostname. This buffer is dynamically
+ * allocated and must be free()ed by the caller. If the functions returns an
+ * error, the pointer is NULL. This function is based on GNU/Hurd's localhostname
+ * function.
+ * rgerhards, 20080-04-10
+ */
+static rsRetVal
+getLocalHostname(uchar **ppName)
+{
+	DEFiRet;
+	uchar *buf = NULL;
+	size_t buf_len = 0;
+
+	assert(ppName != NULL);
+
+	do {
+		if(buf == NULL) {
+			buf_len = 128;        /* Initial guess */
+			CHKmalloc(buf = malloc(buf_len));
+		} else {
+			buf_len += buf_len;
+			CHKmalloc(buf = realloc (buf, buf_len));
+		}
+	} while((gethostname((char*)buf, buf_len) == 0 && !memchr (buf, '\0', buf_len)) || errno == ENAMETOOLONG);
+
+	*ppName = buf;
+	buf = NULL;
+
+finalize_it:
+	if(iRet != RS_RET_OK) {
+		if(buf != NULL)
+			free(buf);
+	}
+	RETiRet;
+}
+
+
 /* closes the UDP listen sockets (if they exist) and frees
  * all dynamically assigned memory. 
  */
@@ -1047,6 +1085,7 @@ CODESTARTobjQueryInterface(net)
 	pIf->closeUDPListenSockets = closeUDPListenSockets;
 	pIf->isAllowedSender = isAllowedSender;
 	pIf->should_use_so_bsdcompat = should_use_so_bsdcompat;
+	pIf->getLocalHostname = getLocalHostname;
 finalize_it:
 ENDobjQueryInterface(net)
 
diff --git a/net.h b/net.h
index 2004dcfc..1b6dbcb6 100644
--- a/net.h
+++ b/net.h
@@ -97,6 +97,7 @@ BEGINinterface(net) /* name must also be changed in ENDinterface macro! */
 	int *(*create_udp_socket)(uchar *hostname, uchar *LogPort, int bIsServer);
 	void (*closeUDPListenSockets)(int *finet);
 	int (*isAllowedSender)(struct AllowedSenders *pAllowRoot, struct sockaddr *pFrom, const char *pszFromHost);
+	rsRetVal (*getLocalHostname)(uchar**);
 	int (*should_use_so_bsdcompat)(void);
 	/* data memebers - these should go away over time... TODO */
 	int    *pACLAddHostnameOnFail; /* add hostname to acl when DNS resolving has failed */
@@ -105,7 +106,7 @@ BEGINinterface(net) /* name must also be changed in ENDinterface macro! */
 	struct AllowedSenders *pAllowedSenders_TCP;
 	struct AllowedSenders *pAllowedSenders_GSS;
 ENDinterface(net)
-#define netCURR_IF_VERSION 1 /* increment whenever you change the interface structure! */
+#define netCURR_IF_VERSION 2 /* increment whenever you change the interface structure! */
 
 /* prototypes */
 PROTOTYPEObj(net);
diff --git a/omfwd.c b/omfwd.c
index 19d09379..67ef4b64 100644
--- a/omfwd.c
+++ b/omfwd.c
@@ -71,7 +71,7 @@ DEFobjCurrIf(net)
 DEFobjCurrIf(tcpclt)
 
 typedef struct _instanceData {
-	char	f_hname[MAXHOSTNAMELEN+1];
+	char	*f_hname;
 	short	sock;			/* file descriptor */
 	int *pSockArray;		/* sockets to use for UDP */
 	enum { /* TODO: we shoud revisit these definitions */
@@ -145,6 +145,9 @@ CODESTARTfreeInstance
 		tcpclt.Destruct(&pData->pTCPClt);
 	}
 
+	if(pData->f_hname != NULL)
+		free(pData->f_hname);
+
 ENDfreeInstance
 
 
@@ -540,10 +543,11 @@ CODE_STD_STRING_REQUESTparseSelectorAct(1)
 		/* TODO: make this if go away! */
 		if(*p == ';') {
 			*p = '\0'; /* trick to obtain hostname (later)! */
-			strcpy(pData->f_hname, (char*) q);
+			CHKmalloc(pData->f_hname = strdup((char*) q));
 			*p = ';';
-		} else
-			strcpy(pData->f_hname, (char*) q);
+		} else {
+			CHKmalloc(pData->f_hname = strdup((char*) q));
+		}
 
 		/* process template */
 		CHKiRet(cflineParseTemplateName(&p, *ppOMSR, 0, OMSR_NO_RQD_TPL_OPTS,
diff --git a/plugins/omgssapi/omgssapi.c b/plugins/omgssapi/omgssapi.c
index 9a7e8ab9..8c6a2006 100644
--- a/plugins/omgssapi/omgssapi.c
+++ b/plugins/omgssapi/omgssapi.c
@@ -4,7 +4,7 @@
  * NOTE: read comments in module-template.h to understand how this file
  *       works!
  *
- * Copyright 2007 Rainer Gerhards and Adiscon GmbH.
+ * Copyright 2007, 2008 Rainer Gerhards and Adiscon GmbH.
  *
  * This file is part of rsyslog.
  *
@@ -79,7 +79,7 @@ DEFobjCurrIf(gssutil)
 DEFobjCurrIf(tcpclt)
 
 typedef struct _instanceData {
-	char	f_hname[MAXHOSTNAMELEN+1];
+	char	*f_hname;
 	short	sock;			/* file descriptor */
 	enum { /* TODO: we shoud revisit these definitions */
 		eDestFORW,
@@ -162,6 +162,9 @@ CODESTARTfreeInstance
 	tcpclt.Destruct(&pData->pTCPClt);
 	if(pData->sock >= 0)
 		close(pData->sock);
+
+	if(pData->f_hname != NULL)
+		free(pData->f_hname);
 ENDfreeInstance
 
 
@@ -592,10 +595,11 @@ CODE_STD_STRING_REQUESTparseSelectorAct(1)
 	/* TODO: make this if go away! */
 	if(*p == ';') {
 		*p = '\0'; /* trick to obtain hostname (later)! */
-		strcpy(pData->f_hname, (char*) q);
+		CHKmalloc(pData->f_hname = strdup((char*) q));
 		*p = ';';
-	} else
-		strcpy(pData->f_hname, (char*) q);
+	} else {
+		CHKmalloc(pData->f_hname = strdup((char*) q));
+	}
 
 	/* process template */
 	CHKiRet(cflineParseTemplateName(&p, *ppOMSR, 0, OMSR_NO_RQD_TPL_OPTS,
@@ -701,6 +705,5 @@ CODEmodInit_QueryRegCFSLineHdlr
 ENDmodInit
 
 #endif /* #ifdef USE_GSSAPI */
-/*
- * vi:set ai:
+/* vi:set ai:
  */
diff --git a/plugins/omrelp/omrelp.c b/plugins/omrelp/omrelp.c
index 39d25812..04571682 100644
--- a/plugins/omrelp/omrelp.c
+++ b/plugins/omrelp/omrelp.c
@@ -53,7 +53,7 @@ DEFobjCurrIf(errmsg)
 static relpEngine_t *pRelpEngine;	/* our relp engine */
 
 typedef struct _instanceData {
-	char f_hname[MAXHOSTNAMELEN+1];
+	char *f_hname;
 	int compressionLevel; /* 0 - no compression, else level for zlib */
 	char *port;
 	int bInitialConnect; /* is this the initial connection request of our module? (0-no, 1-yes) */
@@ -98,6 +98,9 @@ CODESTARTfreeInstance
 	if(pData->pRelpClt != NULL)
 		relpEngineCltDestruct(pRelpEngine, &pData->pRelpClt);
 
+	if(pData->f_hname != NULL)
+		free(pData->f_hname);
+
 ENDfreeInstance
 
 
@@ -284,10 +287,11 @@ CODE_STD_STRING_REQUESTparseSelectorAct(1)
 	/* TODO: make this if go away! */
 	if(*p == ';') {
 		*p = '\0'; /* trick to obtain hostname (later)! */
-		strcpy(pData->f_hname, (char*) q);
+		CHKmalloc(pData->f_hname = strdup((char*) q));
 		*p = ';';
-	} else
-		strcpy(pData->f_hname, (char*) q);
+	} else {
+		CHKmalloc(pData->f_hname = strdup((char*) q));
+	}
 
 	/* process template */
 	CHKiRet(cflineParseTemplateName(&p, *ppOMSR, 0, OMSR_NO_RQD_TPL_OPTS, (uchar*) "RSYSLOG_ForwardFormat"));
diff --git a/syslogd.c b/syslogd.c
index 59fbbc29..65f93c78 100644
--- a/syslogd.c
+++ b/syslogd.c
@@ -306,7 +306,7 @@ uchar *pszWorkDir = NULL;/* name of rsyslog's spool directory (without trailing
 uchar *glblModPath = NULL; /* module load path  - only used during initial init, only settable via -M command line option */
 /* end global config file state variables */
 
-char	LocalHostName[MAXHOSTNAMELEN+1];/* our hostname  - read-only after startup */
+uchar	*LocalHostName;/* our hostname  - read-only after startup */
 char	*LocalDomain;	/* our local domain name  - read-only after startup */
 int	MarkInterval = 20 * 60;	/* interval between marks in seconds - read-only after startup */
 int      family = PF_UNSPEC;     /* protocol family (IPv4, IPv6 or both), set via cmdline */
@@ -897,8 +897,8 @@ logmsgInternal(int pri, char *msg, int flags)
 	CHKiRet(msgConstruct(&pMsg));
 	MsgSetUxTradMsg(pMsg, msg);
 	MsgSetRawMsg(pMsg, msg);
-	MsgSetHOSTNAME(pMsg, LocalHostName);
-	MsgSetRcvFrom(pMsg, LocalHostName);
+	MsgSetHOSTNAME(pMsg, (char*)LocalHostName);
+	MsgSetRcvFrom(pMsg, (char*)LocalHostName);
 	MsgSetTAG(pMsg, "rsyslogd:");
 	pMsg->iFacility = LOG_FAC(pri);
 	pMsg->iSeverity = LOG_PRI(pri);
@@ -1863,6 +1863,8 @@ freeAllDynMemForTermination(void)
 		free(pszMainMsgQFName);
 	if(pModDir != NULL)
 		free(pModDir);
+	if(LocalHostName != NULL)
+		free(LocalHostName);
 }
 
 
@@ -3164,8 +3166,8 @@ 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
 	 */
-	gethostname(LocalHostName, sizeof(LocalHostName));
-	if((p = strchr(LocalHostName, '.'))) {
+	net.getLocalHostname(&LocalHostName);
+	if((p = strchr((char*)LocalHostName, '.'))) {
 		*p++ = '\0';
 		LocalDomain = p;
 	} else {
@@ -3184,17 +3186,19 @@ int realMain(int argc, char **argv)
 		/* 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(LocalHostName);
+		hent = gethostbyname((char*)LocalHostName);
 		if(hent) {
-			snprintf(LocalHostName, sizeof(LocalHostName), "%s", hent->h_name);
+			free(LocalHostName);
+			CHKmalloc(LocalHostName = (uchar*)strdup(hent->h_name));
 				
-			if ( (p = strchr(LocalHostName, '.')) )
+			if((p = strchr((char*)LocalHostName, '.')))
 			{
 				*p++ = '\0';
 				LocalDomain = p;
 			}
 		}
 	}
+dbgprintf("LocalHostname: '%s'\n", LocalHostName);
 
 	/* Convert to lower case to recognize the correct domain laterly */
 	for (p = (char *)LocalDomain ; *p ; p++)
diff --git a/syslogd.h b/syslogd.h
index cbb4bb05..46de8d28 100644
--- a/syslogd.h
+++ b/syslogd.h
@@ -134,7 +134,7 @@ rsRetVal logmsgInternal(int pri, char *msg, int flags);
 void logmsg(msg_t *pMsg, int flags);
 rsRetVal submitMsg(msg_t *pMsg);
 extern int glblHadMemShortage; /* indicates if we had memory shortage some time during the run */
-extern char LocalHostName[];
+extern uchar *LocalHostName;
 extern int family;
 extern int NoHops;
 extern int send_to_all;