tahoe-lafs/src/allmydata/frontends/ftpd.py

311 lines
11 KiB
Python

from zope.interface import implements
from twisted.application import service, strports
from twisted.internet import defer
from twisted.internet.interfaces import IConsumer
from twisted.cred import portal
from twisted.protocols import ftp
from allmydata.interfaces import IDirectoryNode, ExistingChildError, \
NoSuchChildError
from allmydata.immutable.upload import FileHandle
from allmydata.util.fileutil import EncryptedTemporaryFile
class ReadFile:
implements(ftp.IReadFile)
def __init__(self, node):
self.node = node
def send(self, consumer):
d = self.node.read(consumer)
return d # when consumed
class FileWriter:
implements(IConsumer)
def registerProducer(self, producer, streaming):
if not streaming:
raise NotImplementedError("Non-streaming producer not supported.")
# we write the data to a temporary file, since Tahoe can't do
# streaming upload yet.
self.f = EncryptedTemporaryFile()
return None
def unregisterProducer(self):
# the upload actually happens in WriteFile.close()
pass
def write(self, data):
self.f.write(data)
class WriteFile:
implements(ftp.IWriteFile)
def __init__(self, parent, childname, convergence):
self.parent = parent
self.childname = childname
self.convergence = convergence
def receive(self):
self.c = FileWriter()
return defer.succeed(self.c)
def close(self):
u = FileHandle(self.c.f, self.convergence)
d = self.parent.add_file(self.childname, u)
return d
class NoParentError(Exception):
pass
class Handler:
implements(ftp.IFTPShell)
def __init__(self, client, rootnode, username, convergence):
self.client = client
self.root = rootnode
self.username = username
self.convergence = convergence
def makeDirectory(self, path):
d = self._get_root(path)
d.addCallback(lambda (root,path):
self._get_or_create_directories(root, path))
return d
def _get_or_create_directories(self, node, path):
if not IDirectoryNode.providedBy(node):
# unfortunately it is too late to provide the name of the
# blocking directory in the error message.
raise ftp.FileExistsError("cannot create directory because there "
"is a file in the way")
if not path:
return defer.succeed(node)
d = node.get(path[0])
def _maybe_create(f):
f.trap(NoSuchChildError)
return node.create_subdirectory(path[0])
d.addErrback(_maybe_create)
d.addCallback(self._get_or_create_directories, path[1:])
return d
def _get_parent(self, path):
# fire with (parentnode, childname)
path = [unicode(p) for p in path]
if not path:
raise NoParentError
childname = path[-1]
d = self._get_root(path)
def _got_root((root, path)):
if not path:
raise NoParentError
return root.get_child_at_path(path[:-1])
d.addCallback(_got_root)
def _got_parent(parent):
return (parent, childname)
d.addCallback(_got_parent)
return d
def _remove_thing(self, path, must_be_directory=False, must_be_file=False):
d = defer.maybeDeferred(self._get_parent, path)
def _convert_error(f):
f.trap(NoParentError)
raise ftp.PermissionDeniedError("cannot delete root directory")
d.addErrback(_convert_error)
def _got_parent( (parent, childname) ):
d = parent.get(childname)
def _got_child(child):
if must_be_directory and not IDirectoryNode.providedBy(child):
raise ftp.IsNotADirectoryError("rmdir called on a file")
if must_be_file and IDirectoryNode.providedBy(child):
raise ftp.IsADirectoryError("rmfile called on a directory")
return parent.delete(childname)
d.addCallback(_got_child)
d.addErrback(self._convert_error)
return d
d.addCallback(_got_parent)
return d
def removeDirectory(self, path):
return self._remove_thing(path, must_be_directory=True)
def removeFile(self, path):
return self._remove_thing(path, must_be_file=True)
def rename(self, fromPath, toPath):
# the target directory must already exist
d = self._get_parent(fromPath)
def _got_from_parent( (fromparent, childname) ):
d = self._get_parent(toPath)
d.addCallback(lambda (toparent, tochildname):
fromparent.move_child_to(childname,
toparent, tochildname,
overwrite=False))
return d
d.addCallback(_got_from_parent)
d.addErrback(self._convert_error)
return d
def access(self, path):
# we allow access to everything that exists. We are required to raise
# an error for paths that don't exist: FTP clients (at least ncftp)
# uses this to decide whether to mkdir or not.
d = self._get_node_and_metadata_for_path(path)
d.addErrback(self._convert_error)
d.addCallback(lambda res: None)
return d
def _convert_error(self, f):
if f.check(NoSuchChildError):
childname = f.value.args[0].encode("utf-8")
msg = "'%s' doesn't exist" % childname
raise ftp.FileNotFoundError(msg)
if f.check(ExistingChildError):
msg = f.value.args[0].encode("utf-8")
raise ftp.FileExistsError(msg)
return f
def _get_root(self, path):
# return (root, remaining_path)
path = [unicode(p) for p in path]
if path and path[0] == "uri":
d = defer.maybeDeferred(self.client.create_node_from_uri,
str(path[1]))
d.addCallback(lambda root: (root, path[2:]))
else:
d = defer.succeed((self.root,path))
return d
def _get_node_and_metadata_for_path(self, path):
d = self._get_root(path)
def _got_root((root,path)):
if path:
return root.get_child_and_metadata_at_path(path)
else:
return (root,{})
d.addCallback(_got_root)
return d
def _populate_row(self, keys, (childnode, metadata)):
values = []
isdir = bool(IDirectoryNode.providedBy(childnode))
for key in keys:
if key == "size":
if isdir:
value = 0
else:
value = childnode.get_size()
elif key == "directory":
value = isdir
elif key == "permissions":
value = 0600
elif key == "hardlinks":
value = 1
elif key == "modified":
value = metadata.get("mtime", 0)
elif key == "owner":
value = self.username
elif key == "group":
value = self.username
else:
value = "??"
values.append(value)
return values
def stat(self, path, keys=()):
# for files only, I think
d = self._get_node_and_metadata_for_path(path)
def _render((node,metadata)):
assert not IDirectoryNode.providedBy(node)
return self._populate_row(keys, (node,metadata))
d.addCallback(_render)
d.addErrback(self._convert_error)
return d
def list(self, path, keys=()):
# the interface claims that path is a list of unicodes, but in
# practice it is not
d = self._get_node_and_metadata_for_path(path)
def _list((node, metadata)):
if IDirectoryNode.providedBy(node):
return node.list()
return { path[-1]: (node, metadata) } # need last-edge metadata
d.addCallback(_list)
def _render(children):
results = []
for (name, childnode) in children.iteritems():
# the interface claims that the result should have a unicode
# object as the name, but it fails unless you give it a
# bytestring
results.append( (name.encode("utf-8"),
self._populate_row(keys, childnode) ) )
return results
d.addCallback(_render)
d.addErrback(self._convert_error)
return d
def openForReading(self, path):
d = self._get_node_and_metadata_for_path(path)
d.addCallback(lambda (node,metadata): ReadFile(node))
d.addErrback(self._convert_error)
return d
def openForWriting(self, path):
path = [unicode(p) for p in path]
if not path:
raise ftp.PermissionDeniedError("cannot STOR to root directory")
childname = path[-1]
d = self._get_root(path)
def _got_root((root, path)):
if not path:
raise ftp.PermissionDeniedError("cannot STOR to root directory")
return root.get_child_at_path(path[:-1])
d.addCallback(_got_root)
def _got_parent(parent):
return WriteFile(parent, childname, self.convergence)
d.addCallback(_got_parent)
return d
from allmydata.frontends.auth import AccountURLChecker, AccountFileChecker, NeedRootcapLookupScheme
class Dispatcher:
implements(portal.IRealm)
def __init__(self, client):
self.client = client
def requestAvatar(self, avatarID, mind, interface):
assert interface == ftp.IFTPShell
rootnode = self.client.create_node_from_uri(avatarID.rootcap)
convergence = self.client.convergence
s = Handler(self.client, rootnode, avatarID.username, convergence)
def logout(): pass
return (interface, s, None)
class FTPServer(service.MultiService):
def __init__(self, client, accountfile, accounturl, ftp_portstr):
service.MultiService.__init__(self)
# make sure we're using a patched Twisted that uses IWriteFile.close:
# see docs/frontends/FTP-and-SFTP.txt and
# http://twistedmatrix.com/trac/ticket/3462 for details.
if "close" not in ftp.IWriteFile.names():
raise AssertionError("your twisted is lacking a vital patch, see docs/frontends/FTP-and-SFTP.txt")
r = Dispatcher(client)
p = portal.Portal(r)
if accountfile:
c = AccountFileChecker(self, accountfile)
p.registerChecker(c)
if accounturl:
c = AccountURLChecker(self, accounturl)
p.registerChecker(c)
if not accountfile and not accounturl:
# we could leave this anonymous, with just the /uri/CAP form
raise NeedRootcapLookupScheme("must provide some translation")
f = ftp.FTPFactory(p)
s = strports.service(ftp_portstr, f)
s.setServiceParent(self)