[PATCH] libnfsidmap: Don't fail when no domain is set

[Steve Dickson]

A while back I had a complaint that idmapper *always* gets
the uid/gid mapping wrong because the default value defined
in the 'Domain' field (in /etc/idmapd.conf) is never correct.

The person also noticed that by commenting out the Domain 
fields caused the mappings to be correct, since DNS was used 
to obtain the domain. 

But then it was noticed when the domain can not be gotten from
the idmapd.conf or DNS, idmapper crashes which does seem too
robust... imho... 

The first patch comments out the 'Domain' field  in idmapd.conf.
The second patch  sets the 'default_domain' variable in libnfsidmap.c to 
"localdomain" when there is not a domain  defined in /etc/idmapd.conf 
and a domain name can not be obtained from DNS. Of course using
"localdomain" as the domain will cause all mapping to be map to
the 'Nobody-User' user but better than having idmapper crash, imho...  

So these patches do two things, allows mappings to be correct "right out of the box"
when DNS is set up correctly and stops idmapper from dying when there
is no domain name set.

Signed-off-by: Steve Dickson <steved at redhat.com>

diff -up libnfsidmap-0.20/idmapd.conf.orig libnfsidmap-0.20/idmapd.conf
--- libnfsidmap-0.20/idmapd.conf.orig	2006-08-14 17:19:45.000000000 -0400

+++ libnfsidmap-0.20/idmapd.conf	2008-07-11 05:37:58.000000000 -0400

@@ -1,7 +1,7 @@

 [General]

 #Verbosity = 0

-# The following should be set to the local NFSv4 domain name (REQUIRED)

-Domain = local.domain.edu

+# The following should be set to the local NFSv4 domain name

+#Domain = local.domain.edu

 

 [Mapping]

 

diff -up libnfsidmap/libnfsidmap.c.orig libnfsidmap/libnfsidmap.c
--- libnfsidmap/libnfsidmap.c.orig	2006-09-05 10:09:00.000000000 -0400
+++ libnfsidmap/libnfsidmap.c	2008-07-11 05:16:45.000000000 -0400
@@ -54,6 +54,10 @@
 /* forward declarations */
 int set_trans_method(char *);
 
+#ifndef IDMAPD_DEFAULT_DOMAIN
+#define IDMAPD_DEFAULT_DOMAIN "localdomain"
+#endif
+
 static char *default_domain;
 
 #ifndef PATH_IDMAPDCONF
@@ -109,10 +113,12 @@ int nfs4_init_name_mapping(char *conffil
 		dflt = 1;
 		ret = domain_from_dns(&default_domain);
 		if (ret) {
-			IDMAP_LOG(0, ("libnfsidmap: Unable to determine "
-				  "a default nfsv4 domain; consider "
-				  "specifying one in idmapd.conf\n"));
-			return ret;
+			IDMAP_LOG(1, ("libnfsidmap: Unable to determine "
+				  "the NFSv4 domain; Using '%s' as the NFSv4 domain "
+				  "which means UIDs will be mapped to the 'Nobody-User' "
+				  "user defined in %s\n", 
+				  IDMAPD_DEFAULT_DOMAIN, PATH_IDMAPDCONF));
+			default_domain = IDMAPD_DEFAULT_DOMAIN;
 		}
 	}
 	IDMAP_LOG(1, ("libnfsidmap: using%s domain: %s\n",