nfs4server.py

#!/usr/bin/env python
#
# nfs4server.py - NFS4 server in python
#
# Written by Martin Murray <mmurray@deepthought.org>
# and        Fred Isaman   <iisaman@citi.umich.edu>
# Copyright (C) 2001 University of Michigan, Center for 
#                    Information Technology Integration
#


try:
    import psyco
    psyco.full()
except:
    pass

import sys
if sys.hexversion < 0x02030000:
    print "Requires python 2.3 or higher"
    sys.exit(1)
import os
# Allow to be run stright from package root
if  __name__ == "__main__":
    if os.path.isfile(os.path.join(sys.path[0], 'lib', 'testmod.py')):
        sys.path.insert(1, os.path.join(sys.path[0], 'lib'))

from nfs4.nfs4_const import *
from nfs4.nfs4_type import *
import nfs4.nfs4_pack as nfs4_pack
import rpc.rpc as rpc
import nfs4.nfs4lib as nfs4lib
import time, StringIO, random, traceback, codecs
import StringIO
import nfs4.nfs4state as nfs4state
from nfs4.nfs4state import NFS4Error, printverf
from xdrlib import Error as XDRError

unacceptable_names = [ "", ".", ".." ]
unacceptable_characters = [ "/", "~", "#", ]
#unacceptable_unicode_values = [ 0xd800, 0xdb7f, 0xdb80, 0xdb80, 0xdbff, 0xdc00, 0xdf80, 0xdfff, 0xFFFE, 0xFFFF ];

def verify_name(name):
    """Check potential filename and return appropriate error code"""
    if len(name) == 0:
        return NFS4ERR_INVAL
    if len(name) > NFS4_FHSIZE:
        return NFS4ERR_NAMETOOLONG
    if name in unacceptable_names:
        return NFS4ERR_BADNAME
    for character in unacceptable_characters:
        if character in name:
            return NFS4ERR_BADCHAR
    if not verify_utf8(name):
        return NFS4ERR_INVAL
    return NFS4_OK

def verify_utf8(str):
    """Returns True if str is valid utf8, False otherwise"""
    try:
        ustr = codecs.utf_8_decode(str)
        return True
    except UnicodeError:
        return False
            
def access2string(access):
    ret = []
    if access & ACCESS4_READ:
        ret.append("ACCESS4_READ")
    if access & ACCESS4_LOOKUP:
        ret.append("ACCESS4_LOOKUP")
    if access & ACCESS4_MODIFY:
        ret.append("ACCESS4_MODIFY")
    if access & ACCESS4_EXTEND:
        ret.append("ACCESS4_EXTEND")
    if access & ACCESS4_DELETE:
        ret.append("ACCESS4_DELETE")
    if access & ACCESS4_EXECUTE:
        ret.append("ACCESS4_EXECUTE")
    return ' | '.join(ret)

def simple_error(error, *args):
    """Called from function O_<Name>, sets up and returns a simple error response"""
    name = sys._getframe(1).f_code.co_name # Name of calling function
    try:
        if name.startswith("op_"):
            command = name[3:]
            res = globals()[command.upper() + "4res"](error, *args);
            argop4 = nfs_resop4(globals()["OP_" + command.upper()])
            setattr(argop4, "op" + command, res)
            return (error, argop4)
    except KeyError:
        pass
    raise RuntimeError("Bad caller name %s" % name)

class NFS4Server(rpc.RPCServer):
    def __init__(self, rootfh, host, port, pubfh = None):
        rpc.RPCServer.__init__(self, prog=NFS4_PROGRAM, vers=NFS_V4,
                               host=host, port=port)
        self.nfs4packer = nfs4lib.FancyNFS4Packer()
        self.nfs4unpacker = nfs4lib.FancyNFS4Unpacker('')
        self.state = nfs4state.NFSServerState(rootfh)
        self.fhcache = {}
        self.rootfh = rootfh
        self.pubfh = pubfh
        self.verfnum = 0

    def handle_0(self, data, cred):
        print
        print "******** TCP RPC NULL CALL ********"
        print "  flavor = %i" % cred.flavor
        if cred.flavor == rpc.RPCSEC_GSS:
            gss = self.security[cred.flavor]
            body = gss.read_cred(cred.body)
            if body.gss_proc:
                return gss.handle_proc(body, data)
        if data != '':
            print "  ERROR - unexpected data"
            return rpc.GARBAGE_ARGS, ''
        else:
            return rpc.SUCCESS, ''
    
    def handle_1(self, data, cred):
        self.nfs4unpacker.reset(data)
        print
        print "********** TCP RPC CALL ***********"
        ok, results, tag = self.O_Compound()
        try:
            self.nfs4unpacker.done()
        except XDRError:
            print repr(self.nfs4unpacker.get_buffer())
            
            raise
            return rpc.GARBAGE_ARGS, ''
        cmp4res = COMPOUND4res(ok, tag, results)
        self.nfs4packer.reset()
        self.nfs4packer.pack_COMPOUND4res(cmp4res)
        return rpc.SUCCESS, self.nfs4packer.get_buffer()

    def nextverf(self):
        """Return a verifier not previously used by server"""
        self.verfnum += 1
        return nfs4state.packnumber(self.verfnum)

    def prep_client(self):
        self.curr_fh = None
        self.saved_fh = None

    def check_replay(self, op, replay):
        """Pull appropriate info for a replay attempt"""
        fh, args, oldop = replay
        p = nfs4lib.FancyNFS4Packer()
        p.pack_nfs_argop4(op)
        newstr = p.get_buffer()
        p.reset()
        p.pack_nfs_argop4(oldop)
        oldstr = p.get_buffer()
        if oldstr == newstr: # Sadly, op == oldop won't work
            return (fh, args)
        else:
            return (None, (NFS4ERR_BAD_SEQID,))

    def O_Compound(self):
        tag = ''
        try:
            cmp4args = self.nfs4unpacker.unpack_COMPOUND4args()
            tag = cmp4args.tag
        except: # [XDRError, StandardError]:
            #print "ERROR"
            #raise
            return NFS4ERR_BADXDR, [], tag
        print "TCP NFSv4 COMPOUND call, tag: %s, n_ops: %d" % \
              (repr(tag), len(cmp4args.argarray))
        if cmp4args.minorversion <> 0:
            return NFS4ERR_MINOR_VERS_MISMATCH, [], tag
        if not verify_utf8(tag):
            return NFS4ERR_INVAL, [], tag
        self.prep_client()            
        results = []
        ok = NFS4_OK
        for op in cmp4args.argarray:
            opname = nfs_opnum4.get(op.argop, 'op_illegal')
            print "*** %s (%d) ***" % (opname, op.argop)
            ok, result = getattr(self, opname.lower())(op)
            results += [ result ]
            if ok <> NFS4_OK:
                print " ! error %s" % nfsstat4[ok]
                break
        print "Replying. Status %s (%d)" % (nfsstat4[ok], ok)
        return (ok, results, tag)

    # FIXME
    def op_access(self, op):
        print "  CURRENT FILEHANDLE: %s" % self.curr_fh
        print "  REQUESTED ACCESS: %s" % access2string(op.opaccess.access)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        all = ACCESS4_READ | ACCESS4_LOOKUP | ACCESS4_MODIFY | \
            ACCESS4_EXTEND | ACCESS4_DELETE | ACCESS4_EXECUTE
        all = ~all
        if op.opaccess.access & all > 0:
            print "!!!! Received invalid ACCESS bits in op.opaccess.access"
            return simple_error(NFS4ERR_INVAL)
        a4_supported = self.curr_fh.supported_access()
        # according to page 140 of 3530, we only return the supported
        # bitmask with values that were requested by the client.
        a4_supported = op.opaccess.access & a4_supported
        a4_access = self.curr_fh.evaluate_access()
        a4_access = op.opaccess.access & a4_access # bitwise and
        print "  RESULT SUPPORTED: %s" % access2string(a4_supported)
        print "  RESULT ACCESS: %s" % access2string(a4_access)
        a4resok = ACCESS4resok(a4_supported, a4_access)
        return simple_error(NFS4_OK, a4resok)

    def op_close(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        print "  SEQID: %i" % op.opclose.seqid
        stateid = op.opclose.open_stateid
        try:
            replay = self.state.check_seqid(stateid, op.opclose.seqid)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                print "Replay args = %s"%str(args)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            print "  CLOSE fh", self.curr_fh.handle
            self.state.close(stateid)
        except NFS4Error, e:
            self.state.advance_seqid(stateid, op, (e.code,))
            return simple_error(e.code)
        # Return a garbage state id
        sid4 = stateid4(0, '')
        self.state.advance_seqid(stateid, op, (NFS4_OK, sid4), self.curr_fh)
        return simple_error(NFS4_OK, sid4)

    # Note: since currently using ram based fs, we lie here (and in write)
    # and pretend all operations are FILE_SYNC4
    def op_commit(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_ISDIR)
        if self.curr_fh.get_type() != NF4REG:
            return simple_error(NFS4ERR_INVAL)
        if op.opcommit.offset + op.opcommit.count >= 0x10000000000000000:
            return simple_error(NFS4ERR_INVAL)
        c4resok = COMMIT4resok(self.state.write_verifier)
        return simple_error(NFS4_OK, c4resok)

    def op_create(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        e = verify_name(op.opcreate.objname)
        if e: return simple_error(e)
        if not self.curr_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        if not self.curr_fh.lookup(op.opcreate.objname) is None:
            return simple_error(NFS4ERR_EXIST)
        if not (NF4DIR <= op.opcreate.objtype.type <= NF4FIFO):
            return simple_error(NFS4ERR_BADTYPE)
        try:
            old_cinfo = self.curr_fh.fattr4_change
            attrs = op.opcreate.createattrs
            print attrs
            attrset = self.curr_fh.create(op.opcreate.objname, op.opcreate.objtype, attrs)
            new_cinfo = self.curr_fh.fattr4_change
            self.curr_fh = self.curr_fh.lookup(op.opcreate.objname)
        except NFS4Error, e:
            return simple_error(e.code)
        cin4 = change_info4(before=old_cinfo, after=new_cinfo, atomic=1)
        c4resok = CREATE4resok(cinfo=cin4, attrset = attrset)
        return simple_error(NFS4_OK, c4resok)

    # FIXME: have it actually do something
    def op_delegpurge(self, op):
        return simple_error(NFS4ERR_NOTSUPP)
    
    # FIXME: have it actually do something
    def op_delegreturn(self, op):
        return simple_error(NFS4ERR_NOTSUPP)

    def op_getattr(self, op):
        print "  ATTRMASK: %s" % [nfs4lib.get_attr_name(bit) for bit in nfs4lib.bitmap2list(op.opgetattr.attr_request)]
        try:
            if not self.curr_fh:
                return simple_error(NFS4ERR_NOFILEHANDLE)
            attrs = nfs4lib.bitmap2list(op.opgetattr.attr_request)
            attrvals = self.curr_fh.get_attributes(attrs)
        except NFS4Error, e:
            return simple_error(e.code)
        garesok = GETATTR4resok(attrvals)
        return simple_error(NFS4_OK, garesok)

    def op_getfh(self, op):
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        print "  FILEHANDLE %s" % self.curr_fh.handle
        # XXX BUG - fhcache not set on getattr or readdir(getattr)
        self.fhcache[self.curr_fh.handle] = self.curr_fh
        confirmres = GETFH4resok(str(self.curr_fh.handle))
        return simple_error(NFS4_OK, confirmres)

    def op_link(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        print "  SOURCE OBJECT %s" % op.oplink.newname
        if self.curr_fh is None or self.saved_fh is None:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        if self.saved_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_ISDIR)
        e = verify_name(op.oplink.newname)
        if e: return simple_error(e)
        if self.curr_fh.lookup(op.oplink.newname):
            return simple_error(NFS4ERR_EXIST)
        ci_old = self.curr_fh.fattr4_change
        self.curr_fh.hardlink(self.saved_fh, op.oplink.newname)
        ci_new = self.curr_fh.fattr4_change
        l4_cinfo = change_info4(1, ci_old, ci_new)
        l4resok = LINK4resok(l4_cinfo)
        return simple_error(NFS4_OK, l4resok)

    def op_lock(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        try:
            replay = None
            if op.oplock.locker.new_lock_owner:
                owner = op.oplock.locker.open_owner.lock_owner
                seqid = op.oplock.locker.open_owner.lock_seqid
                openstateid = op.oplock.locker.open_owner.open_stateid
                openseqid = op.oplock.locker.open_owner.open_seqid
                replay = self.state.check_seqid(openstateid, openseqid)
            else:
                owner = op.oplock.locker.lock_owner.lock_stateid
                seqid = op.oplock.locker.lock_owner.lock_seqid
                openstateid = None
                replay = self.state.check_seqid(owner, seqid)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            if op.oplock.reclaim:
                raise NFS4Error(NFS4ERR_NO_GRACE)
            if op.oplock.locker.new_lock_owner:
                self.state.new_lockowner(op.oplock.locker.open_owner)
            stateid = self.state.lock(self.curr_fh, owner, op.oplock.locktype,
                                      op.oplock.offset, op.oplock.length)
        except NFS4Error, e:
            if op.oplock.locker.new_lock_owner:
                # FIXME - a bug? compare with replay=check_seqid() above
                self.state.advance_seqid(openstateid, op, (e.code,))
            self.state.advance_seqid(owner, op, (e.code, None, e.lock_denied))
            return simple_error(e.code, None, e.lock_denied)
        l4resok = LOCK4resok(stateid)
        if op.oplock.locker.new_lock_owner:
            self.state.advance_seqid(openstateid, op, (NFS4_OK,))
        self.state.advance_seqid(owner, op, (NFS4_OK, l4resok), self.curr_fh)
        return simple_error(NFS4_OK, l4resok)

    def op_lockt(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)

        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_ISDIR)
        if self.curr_fh.get_type() != NF4REG:
            return simple_error(NFS4ERR_INVAL)
        try:
            self.state.testlock(self.curr_fh,
                                op.oplockt.owner, op.oplockt.locktype,
                                op.oplockt.offset, op.oplockt.length)
        except NFS4Error, e:
            return simple_error(e.code, e.lock_denied)
        return simple_error(NFS4_OK)

    def op_locku(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        stateid = op.oplocku.lock_stateid
        try:
            replay = self.state.check_seqid(stateid, op.oplocku.seqid)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            sid = self.state.unlock(self.curr_fh, stateid, op.oplocku.locktype,
                                    op.oplocku.offset, op.oplocku.length)
        except NFS4Error, e:
            self.state.advance_seqid(stateid, op, (e.code,))
            return simple_error(e.code)
        self.state.advance_seqid(stateid, op, (NFS4_OK, sid), self.curr_fh)
        return simple_error(NFS4_OK, sid)

    def op_lookup(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        print "  REQUESTED OBJECT %s" % op.oplookup.objname
        
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() == NF4LNK:
            return simple_error(NFS4ERR_SYMLINK)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        e = verify_name(op.oplookup.objname)
        if e: return simple_error(e)
        file = self.curr_fh.lookup(op.oplookup.objname)
        if file is None:
            return simple_error(NFS4ERR_NOENT)
        self.curr_fh = file
        return simple_error(NFS4_OK)

    def op_lookupp(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        self.curr_fh = self.curr_fh.do_lookupp()
        print "  PARENT FILEHANDLE %s" % repr(self.curr_fh)
        if self.curr_fh is None:
            return simple_error(NFS4ERR_NOENT)
        return simple_error(NFS4_OK)

    def op_nverify(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        try:
            attrreq = op.opnverify.obj_attributes
            if FATTR4_RDATTR_ERROR in attrreq:
                return simple_error(NFS4ERR_INVAL)
            attrvals = self.curr_fh.get_attributes(attrreq.keys(), ignore=False)
        except NFS4Error, e:
            return simple_error(e.code)
        if attrvals == attrreq:
            return simple_error(NFS4ERR_SAME)
        else:
            return simple_error(NFS4_OK)

    def op_open(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        print "  SEQID: %i" % op.opopen.seqid
        owner = op.opopen.owner
        print "  CLIENTID: %d" % owner.clientid
        print "  OWNER: '%s'" % repr(owner.owner)
        try:
            if not self.state.confirmed.exists(c=owner.clientid):
                if self.state.unconfirmed.exists(c=owner.clientid):
                    raise NFS4Error(NFS4ERR_STALE_CLIENTID)
                else:
                    raise NFS4Error(NFS4ERR_BADOWNER)
            replay = self.state.check_seqid(owner, op.opopen.seqid, False)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            if op.opopen.claim.claim == CLAIM_PREVIOUS:
                raise NFS4Error(NFS4ERR_NO_GRACE)
            if op.opopen.claim.claim in [CLAIM_DELEGATE_CUR, CLAIM_DELEGATE_PREV]:
                raise NFS4Error(NFS4ERR_NOTSUPP)
            if self.curr_fh.get_type() != NF4DIR:
                raise NFS4Error(NFS4ERR_NOTDIR)
            filename = op.opopen.claim.file
            print "  FILE %s" % filename
            e = verify_name(filename)
            if e: raise NFS4Error(e)
            # At this point we know it is CLAIM_NULL with valid filename and cfh
            attrset = 0L
            ci_old = self.curr_fh.fattr4_change
            if op.opopen.openhow.opentype == OPEN4_CREATE:
                print "  CREATING FILE."
                type_reg = createtype4(NF4REG)
                existing = self.curr_fh.lookup(filename)
                if existing is not None:
                    if existing.get_type() == NF4DIR:
                        raise NFS4Error(NFS4ERR_ISDIR)
                    if existing.get_type() == NF4LNK:
                        raise NFS4Error(NFS4ERR_SYMLINK)
                    if existing.get_type() != NF4REG:
                        raise NFS4Error(NFS4ERR_INVAL)
                if op.opopen.openhow.how.mode == EXCLUSIVE4:
                    if existing is not None:
                        if not existing.match_create_verf(op.opopen.openhow.how.createverf):
                            raise NFS4Error(NFS4ERR_EXIST)
                        # Now break out and use existing as is
                    else:
                        # Create file with no attrs and set verifier
                        attrset = self.curr_fh.create(filename, type_reg)
                        existing = self.curr_fh.lookup(filename)
                        existing.create_verf = op.opopen.openhow.how.createverf
                else:
                    attrs = op.opopen.openhow.how.createattrs
                    if existing is not None:
                        if op.opopen.openhow.how.mode == GUARDED4:
                            raise NFS4Error(NFS4ERR_EXIST)
                        # with an existing file ignore attrs except size=0
                        if attrs.has_key(FATTR4_SIZE) and attrs[FATTR4_SIZE]==0:
                            attrset = existing.set_attributes(attrdict={FATTR4_SIZE:0})
                        # Now break out and use existing as is
                    else:
                        attrset = self.curr_fh.create(filename, type_reg, attrs)
                        existing = self.curr_fh.lookup(filename)
            else:
                print "  OPENING EXISTING FILE."
                existing = self.curr_fh.lookup(filename)
                if existing is None:
                    raise NFS4Error(NFS4ERR_NOENT)
                if existing.get_type() == NF4DIR:
                    raise NFS4Error(NFS4ERR_ISDIR)
                if existing.get_type() == NF4LNK:
                    raise NFS4Error(NFS4ERR_SYMLINK)
                if existing.get_type() != NF4REG:
                    raise NFS4Error(NFS4ERR_INVAL)
            # 'existing'  now points to a valid file, so check and set shares
            sid, flags = self.state.open(existing, owner,
                                  op.opopen.share_access, op.opopen.share_deny)
        except NFS4Error, e:
            print "Open error"
            self.state.advance_seqid(owner, op, (e.code,))
            return simple_error(e.code)
        ci_new = self.curr_fh.fattr4_change
        cif4 = change_info4(1, ci_old, ci_new)
        od4 = open_delegation4(delegation_type=OPEN_DELEGATE_NONE)
        o4rok = OPEN4resok(stateid=sid, cinfo=cif4, rflags=flags,
                           attrset=attrset, delegation=od4)
        self.curr_fh = self.curr_fh.lookup(filename)
        self.state.advance_seqid(owner, op, (NFS4_OK, o4rok), self.curr_fh)
        return simple_error(NFS4_OK, o4rok)

    # FIXME: actually open the attr directory, change the filehandle
    def op_openattr(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        return simple_error(NFS4ERR_NOTSUPP)

    def op_open_confirm(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        print "  SEQID: %i" % op.opopen_confirm.seqid
        stateid = op.opopen_confirm.open_stateid
        try:
            replay = self.state.check_seqid(stateid, op.opopen_confirm.seqid,
                                            open_confirm=True)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            if self.curr_fh.get_type() == NF4DIR:
                raise NFS4Error(NFS4ERR_ISDIR)
            if self.curr_fh.get_type() != NF4REG:
                raise NFS4Error(NFS4ERR_INVAL)
            sid = self.state.confirm(self.curr_fh, stateid)
        except NFS4Error, e:
            self.state.advance_seqid(stateid, op, (e.code,))
            return simple_error(e.code)
        oc4resok = OPEN_CONFIRM4resok(sid)
        self.state.advance_seqid(stateid, op, (NFS4_OK, oc4resok), self.curr_fh)
        return simple_error(NFS4_OK, oc4resok)

    def op_open_downgrade(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        stateid = op.opopen_downgrade.open_stateid
        try:
            replay = self.state.check_seqid(stateid, op.opopen_downgrade.seqid)
            if replay:
                self.curr_fh, args = self.check_replay(op, replay)
                return simple_error(*args)
            # Note must cache response, so need to call raise instead of return
            if not self.curr_fh:
                raise NFS4Error(NFS4ERR_NOFILEHANDLE)
            if self.curr_fh.get_type() != NF4REG:
                raise NFS4Error(NFS4ERR_INVAL)
            sid = self.state.downgrade(self.curr_fh, stateid,
                                       op.opopen_downgrade.share_access,
                                       op.opopen_downgrade.share_deny)
        except NFS4Error, e:
            self.state.advance_seqid(stateid, op, (e.code,))
            return simple_error(e.code)
        od4resok = OPEN_DOWNGRADE4resok(sid)
        self.state.advance_seqid(stateid, op, (NFS4_OK, od4resok), self.curr_fh)
        return simple_error(NFS4_OK, od4resok)

    def op_putfh(self, op):
        print "  FILEHANDLE '%s'" % repr(op.opputfh.object)
        # check access!
        if not self.fhcache.has_key(op.opputfh.object):
            return simple_error(NFS4ERR_BADHANDLE)
        self.curr_fh = self.fhcache[op.opputfh.object] 
        return simple_error(NFS4_OK)

    def op_putpubfh(self, op):
        print "  NEW FILEHANDLE %s" % repr(self.curr_fh)
        if self.pubfh is None:
            return simple_error(NFS4ERR_NOTSUPP)
        self.curr_fh = self.pubfh
        return simple_error(NFS4_OK)

    def op_putrootfh(self, op):
        print "  NEW FILEHANDLE %s" % repr(self.curr_fh)
        self.curr_fh = self.rootfh
        return simple_error(NFS4_OK)

    def op_read(self, op):
        offset = op.opread.offset
        count = op.opread.count
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        print "  OFFSET: %d COUNT %d" % (offset, count)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_ISDIR)
        if self.curr_fh.get_type() != NF4REG:
            return simple_error(NFS4ERR_INVAL)
        try:
            self.state.check_read(self.curr_fh, op.opread.stateid,
                                  offset, count)
            read_data = self.curr_fh.read(offset, count)
            print "  READ DATA: len=%i" % len(read_data)
        except NFS4Error, e:
            return simple_error(e.code)
        if len(read_data) < count:
            read_eof = 1
        else:
            read_eof = 0
        r4rok = READ4resok(read_eof, read_data)
        return simple_error(NFS4_OK, r4rok)

    def op_readdir(self, op):
        # We ignore dircount hint
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        print "  COOKIEVERF: %s, %s" % ( repr(op.opreaddir.cookieverf), repr(op.opreaddir.cookie))
        print "  DIRCOUNT: %d MAXCOUNT: %d" % ( op.opreaddir.dircount, op.opreaddir.maxcount)
        print "  ATTRMASK: %s" % [nfs4lib.get_attr_name(bit) for bit in nfs4lib.bitmap2list(op.opreaddir.attr_request)]
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        if op.opreaddir.cookie in [1,2]:
            return simple_error(NFS4ERR_BAD_COOKIE)
        if op.opreaddir.maxcount == 0:
            return simple_error(NFS4ERR_TOOSMALL)
        zeroverf = '\x00\x00\x00\x00\x00\x00\x00\x00'
        if op.opreaddir.cookie == 0 and op.opreaddir.cookieverf != zeroverf:
            return simple_error(NFS4ERR_BAD_COOKIE)
        try:
            verifier = self.curr_fh.getdirverf()
            if op.opreaddir.cookie != 0:
                if op.opreaddir.cookieverf != verifier:
                    return simple_error(NFS4ERR_NOT_SAME)
            try:
                dirlist = self.curr_fh.read_dir(op.opreaddir.cookie)
            except IndexError:
                return simple_error(NFS4ERR_BAD_COOKIE)
            attrs = nfs4lib.bitmap2list(op.opreaddir.attr_request)
            entries = []
            bytecnt = 0
            packer = nfs4lib.FancyNFS4Packer()
            for entry in dirlist:
                # Get file attributes
                try:
                    attrvals = entry.fh.get_attributes(attrs)
                except NFS4Error:
                    if FATTR4_RDATTR_ERROR not in attrs: raise
                    attrvals = entry.fh.get_attributes([FATTR4_RDATTR_ERROR])
                entry.attr = attrvals
                # Compute size of XDR encoding
                e4 = entry4(entry.cookie, entry.name, entry.attr, [])
                packer.reset()
                packer.pack_entry4(e4)
                # Make sure returned value not too big
                bytecnt += len(packer.get_buffer())
                if bytecnt > op.opreaddir.maxcount - 16:
                    break
                # Add file to returned entries
                entries.insert(0,entry)
            if (not entries) and dirlist:
                return simple_error(NFS4ERR_TOOSMALL)
            # Encode entries as linked list
            e4 = []
            for entry in entries:
                e4 = [entry4(entry.cookie, entry.name, entry.attr, nextentry=e4)]
            if len(entries) < len(dirlist):
                d4 = dirlist4(e4, eof=0)
            else:
                d4 = dirlist4(e4, eof=1)
        except NFS4Error, e:
            return simple_error(e.code)
        rdresok = READDIR4resok(cookieverf=verifier, reply=d4)
        return simple_error(NFS4_OK, rdresok)

    def op_readlink(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4LNK:
            return simple_error(NFS4ERR_INVAL)
        link_text = self.curr_fh.read_link()
        print "  LINK_TEXT: %s" % link_text
        rl4resok = READLINK4resok(link_text)
        return simple_error(NFS4_OK, rl4resok)

    def op_remove(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        print "  TARGET: %s" % op.opremove.target
        #XXX: CHECK ACCESS
        if self.curr_fh is None:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        e = verify_name(op.opremove.target)
        if e: return simple_error(e)
        file = self.curr_fh.lookup(op.opremove.target)
        if file is None:
            return simple_error(NFS4ERR_NOENT)
        if file.get_type() == NF4DIR and not file.is_empty():
            return simple_error(NFS4ERR_NOTEMPTY)
        ci_old = self.curr_fh.fattr4_change
        self.curr_fh.remove(op.opremove.target)
        ci_new = self.curr_fh.fattr4_change
        r4_cinfo = change_info4(1, ci_old, ci_new)
        r4resok = REMOVE4resok(r4_cinfo)
        return simple_error(NFS4_OK, r4resok)

    def op_rename(self, op):
        print "  SAVED FILEHANDLE: %s" % repr(self.saved_fh)  # old dir
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh) # new dir
        print "  OLD NAME: %s" % op.oprename.oldname
        print "  NEW NAME: %s" % op.oprename.newname
        if self.curr_fh is None or self.saved_fh is None:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        oldname = op.oprename.oldname
        newname = op.oprename.newname
        e = verify_name(oldname)
        if e: return simple_error(e)
        e = verify_name(newname)
        if e: return simple_error(e)
        if self.curr_fh.get_type() != NF4DIR or \
           self.saved_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        source = self.saved_fh.lookup(oldname)
        target = self.curr_fh.lookup(newname)
        if source is None:
            return simple_error(NFS4ERR_NOENT)
        src_cinfo = self.saved_fh.fattr4_change
        targ_cinfo = self.curr_fh.fattr4_change
        skip = False
        # XXX: check access
        if target is not None:
            if (source.get_type()==NF4DIR) != (target.get_type()==NF4DIR):
                # Incompatible types
                return simple_error(NFS4ERR_EXIST)
            if target.get_type()==NF4DIR and not target.is_empty():
                return simple_error(NFS4ERR_EXIST)
            if source == target:
                # Do nothing and return OK
                skip = True
            else:
                # Remove target and continue as if it had never been
                self.curr_fh.remove(newname)
        if not skip: self.curr_fh.rename(self.saved_fh, oldname, newname)
        r4_src_cinfo = change_info4(1, src_cinfo, self.saved_fh.fattr4_change)
        r4_targ_cinfo = change_info4(1, targ_cinfo, self.curr_fh.fattr4_change)
        r4resok = RENAME4resok(r4_src_cinfo, r4_targ_cinfo)
        return simple_error(NFS4_OK, r4resok)

    # FIXME: need to check principal/security as stated in RFC
    def op_renew(self, op):
        try:
            self.state.renew(op.oprenew.clientid)
        except NFS4Error, e:
            return simple_error(e.code)
        return simple_error(NFS4_OK)

    def op_restorefh(self, op):
        print "  SAVED FILEHANDLE: %s" % repr(self.saved_fh)
        if not self.saved_fh:
            return simple_error(NFS4ERR_RESTOREFH)
        self.curr_fh = self.saved_fh
        return simple_error(NFS4_OK)

    def op_savefh(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        self.saved_fh = self.curr_fh
        return simple_error(NFS4_OK)

    # FIXME: no idea how to set up NFS4_OK conditions; actually get sec information
    def op_secinfo(self, op):
        # STUB
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() != NF4DIR:
            return simple_error(NFS4ERR_NOTDIR)
        e = verify_name(op.opsecinfo.name)
        if e: return simple_error(e)
        resok = [secinfo4(0), secinfo4(1)]
        return simple_error(NFS4_OK, resok)

    def op_setattr(self, op):
        print "  CURRENT FILEHANDLE: %s" % repr(self.curr_fh)
        print op.opsetattr.obj_attributes
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE, 0L)
        try:
            attrdict = op.opsetattr.obj_attributes
            if FATTR4_SIZE in attrdict:
                # This counts as a write, so must do some checking
                if self.curr_fh.get_type() != NF4REG:
                    return simple_error(NFS4ERR_BAD_STATEID, 0L)
                oldsize = self.curr_fh.fattr4_size
                newsize = attrdict[FATTR4_SIZE]
                if oldsize <= newsize:
                    offset = oldsize
                    length = newsize - oldsize
                else:
                    offset = newsize
                    length = oldsize - newsize
                self.state.check_write(self.curr_fh, op.opsetattr.stateid,
                                       offset, length)
            attrset = self.curr_fh.set_attributes(attrdict)
        except NFS4Error, e:
            return simple_error(e.code, e.attrs)
        return simple_error(NFS4_OK, attrset)

    def op_setclientid(self, op):
        print "  ID: %s" % ( op.opsetclientid.client.id)
        x = op.opsetclientid.client.id
        v = op.opsetclientid.client.verifier
        k = (op.opsetclientid.callback, op.opsetclientid.callback_ident)
        p = "Stub" # Principal
        # NOTE this makes the assumption that only one entry can match x=x
        entry = self.state.confirmed.find(x=x)
        entry2 = self.state.unconfirmed.find(x=x)
        if entry is None:
            self.state.unconfirmed.remove(x=x)
            c = self.state.new_clientid()
        elif entry.principal != p:
            return simple_error(NFS4ERR_CLID_INUSE)
        elif entry.v == v:
            self.state.unconfirmed.remove(x=x) # Note change from rfc
            c = entry.c
        elif entry2 is None:
            c = self.state.new_clientid()
        elif entry.s != entry2.s: # Note change from rfc
            self.state.unconfirmed.remove(x=x)
            c = self.state.new_clientid()
        else:
            # This should never happen
            return simple_error(NFS4ERR_INVAL)
        s = self.nextverf()
        print "   VERIFIER: %s" % repr(s)
        self.state.unconfirmed.add(v,x,c,k,s,p)
        resok = SETCLIENTID4resok(c, s)
        return simple_error(NFS4_OK, resok)

    def op_setclientid_confirm(self, op):
        c = op.opsetclientid_confirm.clientid
        s = op.opsetclientid_confirm.setclientid_confirm
        p = "Stub" # Principal
        print "  ARGS, clientid %s, verifier %s" % (c, printverf(s))
        # NOTE this makes the assumption that only one entry can match c=c
        entry = self.state.confirmed.find(c=c)
        entry2 = self.state.unconfirmed.find(c=c)
        if (entry is None or not self.state.confirmed.exists(c=c, s=s)) and \
           (entry2 is None or not self.state.unconfirmed.exists(c=c, s=s)):
            # ie neither matches (**c*s)
            return simple_error(NFS4ERR_STALE_CLIENTID)
        if entry is None and entry2 and entry2.s == s:
            if entry2.principal != p:
                return simple_error(NFS4ERR_CLID_INUSE)
            oldentry = self.state.confirmed.find(x=entry2.x)
            if oldentry is not None:
                self.state.remove_state(oldentry.c)
        elif entry and entry.s == s and not self.state.unconfirmed.exists(v=entry.v, x=entry.x, c=c):
            if entry.principal != p:
                return simple_error(NFS4ERR_CLID_INUSE)
            return simple_error(NFS4_OK)
        elif entry and entry2 and entry.v==entry2.v and  entry.x==entry2.x and entry.s != entry2.s:
            if entry.principal != p or entry2.principal != p:
                return simple_error(NFS4ERR_CLID_INUSE)
        else:
            # This should never happen
            return simple_error(NFS4ERR_INVAL)
        self.state.confirmed.remove(x=entry2.x)
        self.state.confirmed.addentry(entry2)
        self.state.unconfirmed.remove(x=entry2.x)
        self.state.reset_seqid(c)
        return simple_error(NFS4_OK)
            
    def op_verify(self, op):
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        try:
            attrreq = op.opverify.obj_attributes
            if FATTR4_RDATTR_ERROR in attrreq:
                return simple_error(NFS4ERR_INVAL)
            attrvals = self.curr_fh.get_attributes(attrreq.keys(), ignore=False)
        except NFS4Error, e:
            return simple_error(e.code)
        if attrvals == attrreq:
            return simple_error(NFS4_OK)
        else:
            return simple_error(NFS4ERR_NOT_SAME)

    # Note: since currently using ram based fs, we lie here (and in commit)
    # and pretend all operations are FILE_SYNC4
    def op_write(self, op):
        offset = op.opwrite.offset
        data = op.opwrite.data
        print "  CURRENT FILEHANDLE %s" % repr(self.curr_fh)
        print "  OFFSET: %d COUNT %d" % (offset, len(data))
        print "  STATEID { seqid: %s other: %s}" % (repr(op.opwrite.stateid.seqid), repr(op.opwrite.stateid.other))
        if not self.curr_fh:
            return simple_error(NFS4ERR_NOFILEHANDLE)
        if self.curr_fh.get_type() == NF4DIR:
            return simple_error(NFS4ERR_ISDIR)
        if self.curr_fh.get_type() != NF4REG:
            return simple_error(NFS4ERR_INVAL)
        #print "  DATA: %s" % op.opwrite.data
        try:
            self.state.check_write(self.curr_fh, op.opwrite.stateid,
                                   offset, len(data))
            count = self.curr_fh.write(offset, data)
            print "  wrote %i bytes" % count
        except NFS4Error, e:
            return simple_error(e.code)
        w4resok = WRITE4resok(count, FILE_SYNC4, self.state.write_verifier)
        return simple_error(NFS4_OK, w4resok)

    # FIXME: actually release the lock owner
    def op_release_lockowner(self, op):
        return simple_error(NFS4ERR_NOTSUPP)

    def op_illegal(self, op):
        return simple_error(NFS4ERR_OP_ILLEGAL)

def startup(host, port):
    rootfh = nfs4state.VirtualHandle()
    server = NFS4Server(rootfh, port=port, host=host, pubfh=rootfh)
    try:
        import rpc.portmap as portmap
        if not portmap.set(NFS4_PROGRAM, NFS_V4, portmap.IPPROTO_TCP, port):
            raise
        #server.register()
    except:
        print "!! unable to register with portmap"
        pass
    print "Python NFSv4 Server, (c) CITI, Regents of the University of Michigan"
    print "Starting Server, root handle: %s" % rootfh 
    server.run()
    try:
        server.unregister()
    except:
        pass

if __name__ == "__main__":
    port = 2049
    server = ''
    if len(sys.argv) > 2:
        port = int(sys.argv[2])
    if len(sys.argv) > 1:
        server = sys.argv[1]

    startup(server, port)