Patch: select non-conventional principal in gssd

Commit Message

Jurjen Bokma Aug. 6, 2014, 2:59 p.m. UTC

HiAll,

I have a patch to utils/gssd/krb5_util.c that enables kerberized NFS
mounts to succeed even if the principal is not <HOSTNAME>$.

It works by reading another principal name from the [appdefaults]
section of krb5.conf:

[appdefaults]
nfs = {
    ad_principal_name = 129.125.39.115$
}

Patch is attached. Would you please incorporate it in the source if you
find it useful?
Sorry if I'm asking in the wrong place.

Best Regards
Jurjen

Patch

--- utils/gssd/krb5_util.c.orig	2014-08-06 10:54:18.806414170 +0200
+++ utils/gssd/krb5_util.c	2014-08-06 11:01:21.016320365 +0200
@@ -801,7 +801,8 @@ 
 	char *k5err = NULL;
 	int tried_all = 0, tried_default = 0;
 	krb5_principal princ;
-
+	const char *notsetstr = "not set";
+	char *adhostoverride;
 
 	/* Get full target hostname */
 	retval = get_full_hostname(tgtname, targethostname,
@@ -818,11 +819,18 @@ 
 	}
 
 	/* Compute the active directory machine name HOST$ */
-	strcpy(myhostad, myhostname);
-	for (i = 0; myhostad[i] != 0; ++i)
-		myhostad[i] = toupper(myhostad[i]);
-	myhostad[i] = '$';
-	myhostad[i+1] = 0;
+	krb5_appdefault_string(context, "nfs", NULL, "ad_principal_name", notsetstr, &adhostoverride);
+	if (strcmp(adhostoverride, notsetstr) != 0) {
+	        printerr (0, "AD host string overridden with \"%s\" from appdefaults\n", adhostoverride);
+	        /* No overflow: Windows cannot handle strings longer than 19 chars */
+	        strcpy(myhostad, adhostoverride);
+	} else {
+	        strcpy(myhostad, myhostname);
+	        for (i = 0; myhostad[i] != 0; ++i)
+	          myhostad[i] = toupper(myhostad[i]);
+	        myhostad[i] = '$';
+	        myhostad[i+1] = 0;
+	}
 
 	retval = get_full_hostname(myhostname, myhostname, sizeof(myhostname));
 	if (retval)