* kdc_util.c (kdc_get_server_key): Fix to not use cached tgs key

to prevent lossage when it might be out of date by always fetching the correct kvno for the ticket out of the database. git-svn-id: svn://anonsvn.mit.edu/krb5/branches/tlyu-3des-k4@10920 dc483132-0cff-0310-8789-dd5450dbe970
krb5 · Sep 17, 1998 · cc93561 · cc93561
1 parent 949eb46
commit cc93561
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diff --git a/src/kdc/ChangeLog b/src/kdc/ChangeLog
@@ -1,3 +1,9 @@
+Thu Sep 17 18:21:51 1998  Tom Yu  <tlyu@mit.edu>
+
+	* kdc_util.c (kdc_get_server_key): Fix to not use cached tgs key
+	to prevent lossage when it might be out of date by always fetching
+	the correct kvno for the ticket out of the database.
+
 Tue Sep  1 19:34:30 1998  Tom Yu  <tlyu@mit.edu>
 
 	* kerberos_v4.c (compat_decrypt_key): Add

diff --git a/src/kdc/kdc_util.c b/src/kdc/kdc_util.c
@@ -335,12 +335,15 @@ kdc_process_tgs_req(request, from, pkt, ticket, subkey)
 /* XXX This function should no longer be necessary. 
  * The KDC should take the keytab associated with the realm and pass that to 
  * the krb5_rd_req_decode(). --proven
+ *
+ * It's actually still used by do_tgs_req() for u2u auth, and not too
+ * much else. -- tlyu
  */
 krb5_error_code
 kdc_get_server_key(ticket, key, kvno)
     krb5_ticket 	* ticket;
     krb5_keyblock      ** key;
-    krb5_kvno 		* kvno;
+    krb5_kvno 		* kvno;	/* XXX nothing uses this */
 {
     krb5_error_code 	  retval;
     krb5_db_entry 	  server;
@@ -349,64 +352,46 @@ kdc_get_server_key(ticket, key, kvno)
     krb5_key_data	* server_key;
     int			  i;
 
-    if (krb5_principal_compare(kdc_context, tgs_server, ticket->server)) {
-	retval = krb5_copy_keyblock(kdc_context, &tgs_key, key);
-	*kvno = tgs_kvno;
-	return retval;
-    } else {
-	nprincs = 1;
+    nprincs = 1;
 
-	if ((retval = krb5_db_get_principal(kdc_context, ticket->server,
-					    &server, &nprincs,
-					    &more))) {
-	    return(retval);
-	}
-	if (more) {
-	    krb5_db_free_principal(kdc_context, &server, nprincs);
-	    return(KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE);
-	} else if (nprincs != 1) {
-	    char *sname;
-
-	    krb5_db_free_principal(kdc_context, &server, nprincs);
-	    if (!krb5_unparse_name(kdc_context, ticket->server, &sname)) {
-		krb5_klog_syslog(LOG_ERR,"TGS_REQ: UNKNOWN SERVER: server='%s'",
-		       sname);
-		free(sname);
-	    }
-	    return(KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN);
-	}
-	/* 
-	 * Get the latest version of the server key_data and
-	 * convert the key into a real key (it may be encrypted in the database)
-	 *
-	 * Search the key list in the order specified by the key/salt list.
-	 */
-	server_key = (krb5_key_data *) NULL;
-	for (i=0; i<kdc_active_realm->realm_nkstypes; i++) {
-	    krb5_key_salt_tuple *kslist;
-
-	    kslist = (krb5_key_salt_tuple *) kdc_active_realm->realm_kstypes;
-	    if (!krb5_dbe_find_enctype(kdc_context,
-				       &server,
-				       kslist[i].ks_enctype,
-				       -1,
-				       -1,
-				       &server_key))
-		break;
-	}
-	if (!server_key)
-	    return(KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN);
-
-	*kvno = server_key->key_data_kvno;
-	if ((*key = (krb5_keyblock *)malloc(sizeof **key))) {
-	    retval = krb5_dbekd_decrypt_key_data(kdc_context, &master_keyblock,
-					         server_key,
-					         *key, NULL);
-	} else
-	    retval = ENOMEM;
+    if ((retval = krb5_db_get_principal(kdc_context, ticket->server,
+					&server, &nprincs,
+					&more))) {
+	return(retval);
+    }
+    if (more) {
 	krb5_db_free_principal(kdc_context, &server, nprincs);
-	return retval;
+	return(KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE);
+    } else if (nprincs != 1) {
+	char *sname;
+
+	krb5_db_free_principal(kdc_context, &server, nprincs);
+	if (!krb5_unparse_name(kdc_context, ticket->server, &sname)) {
+	    krb5_klog_syslog(LOG_ERR,"TGS_REQ: UNKNOWN SERVER: server='%s'",
+			     sname);
+	    free(sname);
+	}
+	return(KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN);
+    }
+    retval = krb5_dbe_find_enctype(kdc_context, &server,
+				   ticket->enc_part.enctype, -1,
+				   ticket->enc_part.kvno, &server_key);
+    if (retval)
+	goto errout;
+    if (!server_key) {
+	retval = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
+	goto errout;
     }
+    *kvno = server_key->key_data_kvno;
+    if ((*key = (krb5_keyblock *)malloc(sizeof **key))) {
+	retval = krb5_dbekd_decrypt_key_data(kdc_context, &master_keyblock,
+					     server_key,
+					     *key, NULL);
+    } else
+	retval = ENOMEM;
+errout:
+    krb5_db_free_principal(kdc_context, &server, nprincs);
+    return retval;
 }
 
 /* This probably wants to be updated if you support last_req stuff */