doors: allow Transfer to accept a subject to talk to namespace

allow transfer to use a different subject for namespace and pool
operations. Update NFS door to use it.

Acked-by: Dmitry Litvintsev
Target: master
Require-book: no
Require-notes: no

modules/dcache/src/main/java/org/dcache/chimera/nfsv41/door/NFSv41Door.java

@@ -382,7 +382,8 @@ public Layout layoutGet(CompoundContext context, Inode nfsInode, int ioMode, sta
                 InetSocketAddress remote = context.getRpcCall().getTransport().getRemoteSocketAddress();
                 PnfsId pnfsId = new PnfsId(inode.toString());
                 Transfer.initSession();
-                NfsTransfer transfer = new NfsTransfer(_pnfsHandler, Subjects.ROOT, new FsPath("/"),
+                NfsTransfer transfer = new NfsTransfer(_pnfsHandler, Subjects.ROOT,
+                        context.getRpcCall().getCredential().getSubject(),
                         remote, stateid);
 
                 NFS4ProtocolInfo protocolInfo = transfer.getProtocolInfoForPool();
@@ -594,9 +595,9 @@ private static class NfsTransfer extends RedirectedTransfer<PoolDS> {
         private final stateid4 _stateid;
         private final NFS4ProtocolInfo _protocolInfo;
 
-        NfsTransfer(PnfsHandler pnfs, Subject subject, FsPath path, InetSocketAddress client,
+        NfsTransfer(PnfsHandler pnfs, Subject namespaceSubject, Subject ioSubject, InetSocketAddress client,
                 stateid4 stateid) {
-            super(pnfs, subject, path);
+            super(pnfs, namespaceSubject, ioSubject,  new FsPath("/"));
             _stateid = stateid;
             _protocolInfo = new NFS4ProtocolInfo(client, _stateid);
         }

modules/dcache/src/main/java/org/dcache/util/RedirectedTransfer.java

@@ -17,6 +17,10 @@ public class RedirectedTransfer<T> extends Transfer
     private boolean _isRedirected;
     private T _redirectObject;
 
+    public RedirectedTransfer(PnfsHandler pnfs, Subject namespaceSubject, Subject subject, FsPath path) {
+        super(pnfs, namespaceSubject, subject, path);
+    }
+
     public RedirectedTransfer(PnfsHandler pnfs, Subject subject, FsPath path) {
         super(pnfs, subject, path);
     }

modules/dcache/src/main/java/org/dcache/util/Transfer.java

@@ -108,20 +108,32 @@ public class Transfer implements Comparable<Transfer>
      * Constructs a new Transfer object.
      *
      * @param pnfs PnfsHandler used for pnfs communication
-     * @param subject The subject performing the transfer
+     * @param namespaceSubject The subject performing the namespace operations
+     * @param ioSubject The subject performing the transfer
      * @param path The path of the file to transfer
      */
-    public Transfer(PnfsHandler pnfs, Subject subject, FsPath path)
-    {
-        _pnfs = new PnfsHandler(pnfs, subject);
-        _subject = subject;
+    public Transfer(PnfsHandler pnfs, Subject namespaceSubject, Subject ioSubject, FsPath path) {
+        _pnfs = new PnfsHandler(pnfs, namespaceSubject);
+        _subject = ioSubject;
         _path = path;
         _startedAt = System.currentTimeMillis();
         _sessionId = _sessionCounter.next();
         _session = CDC.getSession();
         _checkStagePermission = new CheckStagePermission(null);
     }
 
+    /**
+     * Constructs a new Transfer object.
+     *
+     * @param pnfs PnfsHandler used for pnfs communication
+     * @param subject The subject performing the transfer and namespace operations
+     * @param path The path of the file to transfer
+     */
+    public Transfer(PnfsHandler pnfs, Subject subject, FsPath path)
+    {
+        this(pnfs, subject, subject, path);
+    }
+
     /**
      * Returns a ProtocolInfo suitable for selecting a pool. By
      * default the protocol info set with setProtocolInfo is returned.