#
# This patch disables reverse DNS IP address look-ups that MIT does by default.
# Solaris krb has never done reverse look-ups so this makes MIT krb behave like
# Solaris in this regard.  MIT will not take this change upstream.
# Patch source: in-house
#
--- a/src/lib/krb5/os/sn2princ.c
+++ b/src/lib/krb5/os/sn2princ.c
@@ -36,7 +36,7 @@
 #endif
 
 #if !defined(DEFAULT_RDNS_LOOKUP)
-#define DEFAULT_RDNS_LOOKUP 1
+#define DEFAULT_RDNS_LOOKUP 0
 #endif
 
 /*
--- a/src/man/krb5.conf.man
+++ b/src/man/krb5.conf.man
@@ -473,7 +473,7 @@ default, if allowed by the KDC.  The default value is false.
 If this flag is true, reverse name lookup will be used in addition
 to forward name lookup to canonicalizing hostnames for use in
 service principal names.  If \fBdns_canonicalize_hostname\fP is set
-to false, this flag has no effect.  The default value is true.
+to false, this flag has no effect.  The default value is false.
 .TP
 .B \fBrealm_try_domains\fP
 Indicate whether a host\(aqs domain components should be used to
--- a/src/tests/t_sn2princ.py
+++ b/src/tests/t_sn2princ.py
@@ -6,10 +6,12 @@ offline = (len(args) > 0 and args[0] != "no")
 conf = {'domain_realm': {'kerberos.org': 'R1',
                          'example.com': 'R2',
                          'mit.edu': 'R3'}}
+rdns_conf = {'libdefaults': {'rdns': 'true'}}
 no_rdns_conf = {'libdefaults': {'rdns': 'false'}}
 no_canon_conf = {'libdefaults': {'dns_canonicalize_hostname': 'false'}}
 
 realm = K5Realm(create_kdb=False, krb5_conf=conf)
+rdns = realm.special_env('rdns', False, krb5_conf=rdns_conf)
 no_rdns = realm.special_env('no_rdns', False, krb5_conf=no_rdns_conf)
 no_canon = realm.special_env('no_canon', False, krb5_conf=no_canon_conf)
 
@@ -30,6 +32,10 @@ def testnc(host, princhost, princrealm):
     # Test with the host-based name type with canonicalization disabled.
     testbase(host, 'srv-hst', princhost, princrealm, env=no_canon)
 
+def testr(host, princhost, princrealm):
+    # Test with the host-based name type with reverse lookup enabled.
+    testbase(host, 'srv-hst', princhost, princrealm, env=rdns)
+
 def testnr(host, princhost, princrealm):
     # Test with the host-based name type with reverse lookup disabled.
     testbase(host, 'srv-hst', princhost, princrealm, env=no_rdns)
@@ -96,9 +102,14 @@ if rname == fname:
               '%s reverse resolves to %s '
               'which should be different from %s' % (oname, rname, fname))
 
-# Test default canonicalization (forward and reverse lookup).
-test(oname, rname, 'R3')
-test(oname + ':123', rname + ':123', 'R3')
-test(oname + ':xyZ', rname + ':xyZ', 'R3')
+# Test forward+reverse lookup canonicalization (rdns=true).
+testr(oname, rname, 'R3')
+testr(oname + ':123', rname + ':123', 'R3')
+testr(oname + ':xyZ', rname + ':xyZ', 'R3')
+
+# Test default canonicalization (forward lookup).
+test(oname, fname, 'R1')
+test(oname + ':123', fname + ':123', 'R1')
+test(oname + ':xyZ', fname + ':xyZ', 'R1')
 
 success('krb5_sname_to_principal tests')