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+# -*- coding: utf-8 -*-
+#
+# Copyright 2013 Bernhard R. Link <brlink@debian.org>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# SOFTWARE IN THE PUBLIC INTEREST, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR
+# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+# DEALINGS IN THE SOFTWARE.
+#
+
+"""
+This is a sftp module to be used in reprepro's outsftphook example.
+Like the sftp binary it calls ssh to do the connection in a secure
+way and then speaks the sftp subsystem language over that connection.
+"""
+
+
+import os, subprocess, select
+
+class EnumInternException(Exception):
+ def __init__(self, v):
+ super().__init__(v)
+ self.value = v
+
+class _EnumType(type):
+ """
+ Metaclass for Enum. Allows one to set values as parameters.
+ """
+ def __new__(cls, name, bases, namespace, **values):
+ return type.__new__(cls, name, bases, namespace)
+ def __init__(self, name, bases, namespace, **values):
+ super().__init__(name, bases, namespace)
+ if bases:
+ self._byvalue = dict()
+ self._byname = dict()
+ if values:
+ for k,v in values.items():
+ self._create_instance(k, v)
+
+class Enum(metaclass=_EnumType):
+ """
+ An enum is a class with a fixed set of instances.
+ Each instance has a name and a integer value.
+ If a new new instance is to be created, one of those
+ fix instances is returned instead.
+ """
+ @classmethod
+ def _create_instance(cls, name, value):
+ # create a new instance:
+ result = super(Enum, cls).__new__(cls)
+ if isinstance(name, str):
+ result.name = name
+ else:
+ result.name = name[0]
+ result.__name__ = result.name
+ result.value = value
+ cls._byvalue[value] = result
+ if isinstance(name, str):
+ cls._byname[name] = result
+ setattr(cls, name, result)
+ else:
+ for n in name:
+ cls._byname[n] = result
+ setattr(cls, n, result)
+ return result
+ def __new__(cls, l):
+ try:
+ if isinstance(l, cls):
+ return l
+ elif isinstance(l, int):
+ return cls._byvalue[l]
+ elif isinstance(l, str):
+ return cls._byname[l]
+ else:
+ raise EnumInternException(repr(l))
+ except KeyError:
+ raise EnumInternException(repr(l))
+ def __init__(self, l):
+ pass
+ def __int__(self):
+ return self.value
+ def __str__(self):
+ return self.name
+ def __repr__(self):
+ return "%s.%s.%s" % (type(self).__module__, type(self).__name__, self.name)
+
+class _BitmaskType(type):
+ """
+ Metaclass for Bitmask types. Allows one to set values as parameters.
+ """
+ @classmethod
+ def __prepare__(cls, name, bases, **values):
+ namespace = type.__prepare__(cls, name, bases)
+ if values:
+ flagcls = _EnumType.__new__(type, "flags of " + name, (Enum,), dict())
+ flagcls._byvalue = dict()
+ flagcls._byname = dict()
+ namespace["_Values"] = flagcls
+ for (k,v) in values.items():
+ if isinstance(v, int):
+ e = flagcls._create_instance(k, v)
+ e.mask = v
+ else:
+ e = flagcls._create_instance(k, v[0])
+ e.mask = v[1]
+ namespace[k] = e
+ return namespace
+ def __new__(cls, name, bases, namespace, **values):
+ return type.__new__(cls, name, bases, namespace)
+ def __init__(self, name, bases, namespace, **values):
+ return super().__init__(name, bases, namespace)
+
+class Bitmask(set, metaclass=_BitmaskType):
+ def __init__(self, l):
+ if isinstance(l, int):
+ super().__init__([i
+ for (k,i)
+ in self._Values._byvalue.items()
+ if (l & i.mask) == k])
+ if l != int(self):
+ raise Exception("Unrepresentable number %d (got parsed as %s = %d)" %
+ (l, str(self), int(self)))
+ elif isinstance(l, str):
+ try:
+ super().__init__([self._Values(i)
+ for i
+ in l.split("|")])
+ # test for inconsistencies:
+ type(self)(int(self))
+ except EnumInternException as e:
+ raise Exception("Invalid value '%s' in value '%s' for %s" %
+ (e.value, str(l), type(self).__name__))
+ else:
+ try:
+ super().__init__([self._Values(i) for i in l])
+ # test for inconsistencies:
+ type(self)(int(self))
+ except EnumInternException as e:
+ raise Exception("Invalid value '%s' in value '%s' for %s" %
+ (e.value, str(l), type(self).__name__))
+ def __int__(self):
+ v = 0
+ for i in self:
+ v = v | int(i)
+ return v
+ def __str__(self):
+ return "|".join([str(i) for i in self])
+
+class SSH_FILEXFER(Bitmask, ATTR_SIZE = 0x00000001,
+ ATTR_UIDGID = 0x00000002,
+ ATTR_PERMISSIONS = 0x00000004,
+ ATTR_ACMODTIME = 0x00000008,
+ ATTR_EXTENDED = 0x80000000):
+ pass
+
+def ssh_data(b):
+ return len(b).to_bytes(4, byteorder='big') + b
+def ssh_string(s):
+ b = str(s).encode(encoding='utf-8')
+ return len(b).to_bytes(4, byteorder='big') + b
+def ssh_u8(i):
+ return int(i).to_bytes(1, byteorder='big')
+def ssh_u32(i):
+ return int(i).to_bytes(4, byteorder='big')
+def ssh_u64(i):
+ return int(i).to_bytes(8, byteorder='big')
+def ssh_attrs(**opts):
+ flags = SSH_FILEXFER(0)
+ extended = []
+ for key in opts:
+ if key == 'size':
+ flags.add(SSH_FILEXFER.ATTR_SIZE)
+ elif key == 'uid' or key == 'gid':
+ flags.add(SSH_FILEXFER.ATTR_UIDGID)
+ elif key == 'permissions':
+ flags.add(SSH_FILEXFER.ATTR_PERMISSIONS)
+ elif key == 'atime' or key == 'mtime':
+ flags.add(SSH_FILEXFER.ATTR_ACMODTIME)
+ elif '@' in key:
+ extended.add(opts[key])
+ else:
+ raise SftpException("Unsupported file attribute type %s" % repr(key))
+ if extended:
+ flags.add(SSH_FILEXFER.ATTR_EXTENDED)
+ b = ssh_u32(int(flags))
+ if SSH_FILEXFER.ATTR_SIZE in flags:
+ b = b + ssh_u64(opts['size'])
+ if SSH_FILEXFER.ATTR_UIDGID in flags:
+ b = b + ssh_u32(opts['uid'])
+ b = b + ssh_u32(opts['gid'])
+ if SSH_FILEXFER.ATTR_PERMISSIONS in flags:
+ b = b + ssh_u32(opts['permissions'])
+ if SSH_FILEXFER.ATTR_ACMODTIME in flags:
+ b = b + ssh_u32(opts['atime'])
+ b = b + ssh_u32(opts['mtime'])
+ if SSH_FILEXFER.ATTR_EXTENDED in flags:
+ b = b + ssh_u32(len(extended))
+ for key in extended:
+ b = b + ssh_string(key)
+ b = b + ssh_data(opts[key])
+ return b
+
+def ssh_getu32(m):
+ v = int.from_bytes(m[:4], byteorder='big')
+ return v, m[4:]
+def ssh_getstring(m):
+ l = int.from_bytes(m[:4], byteorder='big')
+ return (m[4:4+l].decode(encoding='utf-8'), m[4+l:])
+def ssh_getdata(m):
+ l = int.from_bytes(m[:4], byteorder='big')
+ return (m[4:4+l], m[4+l:])
+def ssh_getattrs(m):
+ attrs = dict()
+ flags, m = ssh_getu32(m)
+ flags = SSH_FILEXFER(flags)
+ if SSH_FILEXFER.ATTR_SIZE in flags:
+ attrs['size'], m = ssh_getu64(m)
+ if SSH_FILEXFER.ATTR_UIDGID in flags:
+ attrs['uid'], m = ssh_getu32(m)
+ attrs['gid'], m = ssh_getu32(m)
+ if SSH_FILEXFER.ATTR_PERMISSIONS in flags:
+ attrs['permissions'], m = ssh_getu32(m)
+ if SSH_FILEXFER.ATTR_ACMODTIME in flags:
+ attrs['atime'], m = ssh_getu32(m)
+ attrs['mtime'], m = ssh_getu32(m)
+ if SSH_FILEXFER.ATTR_EXTENDED in flags:
+ count, m = ssh_getu32(m)
+ while count > 0:
+ count -= 1
+ key, m = ssh_getstring(m)
+ attrs[key], m = ssh_getdata(m)
+ return (attrs, m)
+
+class SftpException(Exception):
+ pass
+
+class SftpStrangeException(SftpException):
+ """Unparseable stuff from server"""
+ pass
+
+class SftpUnexpectedAnswerException(SftpStrangeException):
+ def __init__(self, answer, request):
+ super().__init__("Unexpected answer '%s' to request '%s'" %
+ (str(answer), str(request)))
+
+class SftpTooManyRequestsException(SftpException):
+ def __init__(self):
+ super().__init__("Too many concurrent requests (out of request ids)")
+
+class SftpInternalException(SftpException):
+ """a programming or programmer mistake"""
+ pass
+
+class Request:
+ def __init__(self, **args):
+ self.data = args
+ pass
+ def __int__(self):
+ return self.requestid
+ def __str__(self):
+ return type(self).__name__ + "(" + " ".join(["%s=%s" % (key, repr(val))
+ for (key, val) in self.data.items()]) + ")"
+ @classmethod
+ def bin(cls, conn, req, *payload):
+ s = 5
+ for b in payload:
+ s = s + len(b)
+ # print("Sending packet of type %d and size %d" % (cls.typeid, s))
+ r = ssh_u32(s) + ssh_u8(cls.typeid) + ssh_u32(int(req))
+ for b in payload:
+ r = r + b
+ return r
+ def send(self, conn):
+ conn.requests[int(self)] = self
+ self.conn = conn
+ conn.send(self.bin(conn, self, **self.data))
+ def done(self):
+ if self.requestid != None:
+ del self.conn.requests[self.requestid]
+ self.requestid = None
+
+class NameRequest(Request):
+ """Base class for requests with a single name as argument"""
+ def __init__(self, name):
+ super().__init__(name = name)
+ @classmethod
+ def bin(cls, conn, req, name):
+ return super().bin(conn, req, ssh_string(name))
+
+class HandleRequest(Request):
+ """Base class for requests with a single name as argument"""
+ def __init__(self, handle):
+ super().__init__(handle = handle)
+ @classmethod
+ def bin(cls, conn, req, handle):
+ return super().bin(conn, req, ssh_data(handle))
+
+class NameAttrRequest(Request):
+ """Base class for requests with a name and attributes as argument"""
+ def __init__(self, name, **attrs):
+ super().__init__(name = name, attrs = attrs)
+ @classmethod
+ def bin(cls, conn, req, name, attrs):
+ return super().bin(conn, req,
+ ssh_string(name),
+ ssh_attrs(**attrs))
+
+class INIT(Request):
+ typeid = 1
+ @classmethod
+ def bin(cls, conn, version):
+ # INIT has no request id but instead sends a protocol version
+ return super().bin(conn, int(version))
+
+class SSH_FXF(Bitmask, READ = 0x00000001,
+ WRITE = 0x00000002,
+ APPEND = 0x00000004,
+ CREAT = 0x00000008,
+ TRUNC = 0x00000010,
+ EXCL = 0x00000020):
+ pass
+
+class OPEN(Request):
+ typeid = 3
+ def __init__(self, name, flags, **attributes):
+ super().__init__(name = name, flags = SSH_FXF(flags), attrs = attributes)
+ @classmethod
+ def bin(cls, conn, req, name, flags, attrs):
+ return super().bin(conn, req,
+ ssh_string(name),
+ ssh_u32(flags),
+ ssh_attrs(**attrs))
+
+class CLOSE(HandleRequest):
+ typeid = 4
+
+class READ(Request):
+ typeid = 5
+ def __init__(self, handle, start, length):
+ super().__init__(handle = handle, start = start, length = int(length))
+ @classmethod
+ def bin(cls, conn, req, handle, start, length):
+ return super().bin(conn, req, ssh_data(handle), ssh_u64(start), ssh_u32(length))
+
+class WRITE(Request):
+ typeid = 6
+ def __init__(self, handle, start, data):
+ super().__init__(handle = handle, start = start, data = bytes(data))
+ @classmethod
+ def bin(cls, conn, req, handle, start, data):
+ return super().bin(conn, req, ssh_data(handle), ssh_u64(start), ssh_data(data))
+
+class LSTAT(NameRequest):
+ typeid = 7
+
+class FSTAT(HandleRequest):
+ typeid = 8
+
+class SETSTAT(NameAttrRequest):
+ typeid = 9
+
+class FSETSTAT(Request):
+ typeid = 10
+ def __init__(self, handle, **attrs):
+ super().__init__(handle = handle, attrs = attrs)
+ @classmethod
+ def bin(cls, conn, req, name, attrs):
+ return super().bin(conn, req,
+ ssh_data(handle),
+ ssh_attrs(**attrs))
+
+class OPENDIR(NameRequest):
+ typeid = 11
+
+class READDIR(HandleRequest):
+ typeid = 12
+
+class REMOVE(NameRequest):
+ typeid = 13
+
+class MKDIR(NameAttrRequest):
+ typeid = 14
+
+class RMDIR(NameRequest):
+ typeid = 15
+
+class REALPATH(NameRequest):
+ typeid = 16
+
+class STAT(NameRequest):
+ typeid = 17
+
+class SSH_FXF_RENAME(Bitmask, OVERWRITE = 0x00000001,
+ ATOMIC = 0x00000002,
+ NATIVE = 0x00000004):
+ pass
+
+class RENAME(Request):
+ typeid = 18
+ def __init__(self, src, dst, flags):
+ if not isinstance(flags, SSH_FXF_RENAME):
+ flags = SSH_FXF_RENAME(flags)
+ super().__init__(src = src, dst = dst, flags = flags)
+ @classmethod
+ def bin(cls, conn, req, src, dst, flags):
+ # TODO: Version 3 has no flags (though they do not seem to harm)
+ return super().bin(conn, req, ssh_string(src),
+ ssh_string(dst), ssh_u32(flags))
+
+class READLINK(NameRequest):
+ typeid = 19
+
+class SYMLINK(Request):
+ typeid = 20
+ def __init__(self, name, dest):
+ super().__init__(name = name, dest = dest)
+ @classmethod
+ def bin(cls, conn, req, name, dest):
+ # TODO: this is openssh and not the standard (they differ)
+ return super().bin(conn, req, ssh_string(dest),
+ ssh_string(name))
+
+class EXTENDED(Request):
+ typeid = 200
+ # TODO?
+
+################ Answers ################
+
+class Answer:
+ def __int__(self):
+ return self.id
+ # Fallbacks, can be removed once all are done:
+ def __init__(self, m):
+ self.data = m
+ def __str__(self):
+ return "%s %s" % (type(self).__name__, repr(self.data))
+
+class VERSION(Answer):
+ id = 2
+
+class SSH_FX(Enum,
+ OK = 0,
+ EOF = 1,
+ NO_SUCH_FILE = 2,
+ PERMISSION_DENIED = 3,
+ FAILURE = 4,
+ BAD_MESSAGE = 5,
+ NO_CONNECTION = 6,
+ CONNECTION_LOST = 7,
+ OP_UNSUPPORTED = 8,
+ INVALID_HANDLE = 9,
+ NO_SUCH_PATH = 10,
+ FILE_ALREADY_EXISTS = 11,
+ WRITE_PROTECT = 12,
+ NO_MEDIA = 13
+):
+ pass
+
+class STATUS(Answer):
+ id = 101
+ def __init__(self, m):
+ s, m = ssh_getu32(m)
+ self.status = SSH_FX(s)
+ self.message, m = ssh_getstring(m)
+ self.lang, m = ssh_getstring(m)
+ def __str__(self):
+ return "STATUS %s: %s[%s]" % (
+ str(self.status),
+ self.message,
+ self.lang)
+
+class HANDLE(Answer):
+ id = 102
+ def __init__(self, m):
+ self.handle, m = ssh_getdata(m)
+ def __str__(self):
+ return "HANDLE %s" % repr(self.handle)
+
+class DATA(Answer):
+ id = 103
+ def __init__(self, m):
+ self.data, m = ssh_getdata(m)
+ def __str__(self):
+ return "DATA %s" % repr(self.data)
+
+class NAME(Answer):
+ id = 104
+ def __init__(self, m):
+ count, m = ssh_getu32(m)
+ self.names = []
+ while count > 0:
+ count -= 1
+ filename, m = ssh_getstring(m)
+ longname, m = ssh_getstring(m)
+ attrs, m = ssh_getattrs(m)
+ self.append((filename, longname, attrs))
+
+ def __str__(self):
+ return "NAME" + "".join(("%s:%s:%s" % (repr(fn), repr(ln), str(attrs))
+ for (fn,ln,attrs) in self.names))
+
+class ATTRS(Answer):
+ id = 105
+ def __init__(self, m):
+ self.attrs, m = ssh_getattrs(m)
+
+ def __str__(self):
+ return "ATTRS %s" % str(self.attrs)
+
+class EXTENDED_REPLY(Answer):
+ id = 201
+ # TODO?
+
+################ Tasks ################
+
+class Task:
+ """A task is everything that sends requests,
+ receives answers, uses collectors or is
+ awakened by collectors.
+ """
+ def start(self, connection):
+ self.connection = connection
+ def enqueueRequest(self, request):
+ request.task = self
+ self.connection.enqueueRequest(request)
+ def sftpanswer(self, a):
+ raise SftpInternalException("unimplemented sftpanswer called")
+ def writeready(self):
+ raise SftpInternalException("unimplemented writeready called")
+ def parentinfo(self, command):
+ raise SftpInternalException("unimplemented parentinfo called")
+
+class TaskFromGenerator(Task):
+ """A wrapper around a python corotine (generator)"""
+ def __init__(self, gen):
+ super().__init__()
+ self.gen = gen
+ def start(self, connection):
+ super().start(connection)
+ self.enqueue(next(self.gen))
+ def parentinfo(self, command):
+ self.enqueue(self.gen.send(command))
+ def sftpanswer(self, answer):
+ self.enqueue(self.gen.send(answer))
+ def writeready(self):
+ self.enqueue(self.gen.send('canwrite'))
+ def __str__(self):
+ return "Task(by %s)" % self.gen
+ def enqueue(self, joblist):
+ if len(joblist) == 0:
+ return
+ for job in joblist:
+ if isinstance(job, Request):
+ self.enqueueRequest(job)
+ elif job == 'wantwrite':
+ self.connection.enqueueTask(self)
+ elif (isinstance(job, tuple) and len(job) == 2 and
+ isinstance(job[0], Task)):
+ if DebugMode.LOCKS in self.debug:
+ print("parentinfo", job,
+ **self.debugopts)
+ job[0].parentinfo(job[1])
+ elif (isinstance(job, tuple) and len(job) >= 2 and
+ issubclass(job[1], Collector)):
+ self.connection.collect(self, *job)
+ elif isinstance(job, Task):
+ self.connection.start(job)
+ else:
+ raise SftpInternalException("strange result from generator")
+
+
+class Collector(Task):
+ """ Collectors collect information from Tasks and send them
+ triggers at requested events (parent directory created,
+ another file can be processed, ...)
+ """
+ def childinfo(self, who, command):
+ raise SftpInternalException("unimplemented parentinfo called")
+
+class DebugMode(Bitmask, **{
+ 'COOKED_IN': 1,
+ 'COOKED_OUT': 2,
+ 'RAW_IN_STAT': 4,
+ 'RAW_OUT_STAT': 8,
+ 'RAW_IN': 16,
+ 'RAW_OUT': 32,
+ 'ENQUEUE': 64,
+ 'LOCKS': 128,
+}):
+ pass
+
+class Connection:
+ def next_request_id(self):
+ i = self.requestid_try_next
+ while i in self.requests:
+ i = (i + 1) % 0x100000000
+ if i == self.requestid_try_next:
+ raise SftpTooManyRequestsException()
+ self.requestid_try_next = (i + 1) % 0x100000000
+ return i
+ def __init__(self, servername, sshcommand="ssh", username=None, ssh_options=[], debug=0, debugopts=dict(), maxopenfiles=10):
+ self.debug = DebugMode(debug)
+ self.debugopts = debugopts
+ self.requests = dict()
+ self.collectors = dict()
+ self.queue = list()
+ self.wantwrite = list()
+ self.requestid_try_next = 17
+ self.semaphores = {'openfile': maxopenfiles}
+
+ commandline = [sshcommand]
+ if ssh_options:
+ commandline.extend(ssh_options)
+ # those defaults are after the user-supplied ones so they can be overridden.
+ # (earlier ones win with ssh).
+ commandline.extend(["-oProtocol 2", # "-oLogLevel DEBUG",
+ "-oForwardX11 no", "-oForwardAgent no",
+ "-oPermitLocalCommand no",
+ "-oClearAllForwardings yes"])
+ if username:
+ commandline.extend(["-l", username])
+ commandline.extend(["-s", "--", servername, "sftp"])
+ self.connection = subprocess.Popen(commandline,
+ close_fds = True,
+ stdin = subprocess.PIPE,
+ stdout = subprocess.PIPE,
+ bufsize = 0)
+ self.poll = select.poll()
+ self.poll.register(self.connection.stdout, select.POLLIN)
+ self.inbuffer = bytes()
+ self.send(INIT.bin(self, 3))
+ t,b = self.getpacket()
+ if t != VERSION.id:
+ raise SftpUnexpectedAnswerException(b, "INIT")
+ # TODO: parse answer data (including available extensions)
+ def close(self):
+ self.connection.send_signal(15)
+ def getmoreinput(self, minlen):
+ while len(self.inbuffer) < minlen:
+ o = self.connection.stdout.read(minlen - len(self.inbuffer))
+ if o == None:
+ continue
+ if len(o) == 0:
+ raise SftpStrangeException("unexpected EOF")
+ self.inbuffer = self.inbuffer + o
+ def getpacket(self):
+ self.getmoreinput(5)
+ s = int.from_bytes(self.inbuffer[:4], byteorder='big')
+ if s < 1:
+ raise SftpStrangeException("Strange size field in Paket from server!")
+ t = self.inbuffer[4]
+ if DebugMode.RAW_IN_STAT in self.debug:
+ print("receiving packet of length %d and type %d " %
+ (s, t), **self.debugopts)
+ s = s - 1
+ self.inbuffer = self.inbuffer[5:]
+ self.getmoreinput(s)
+ d = self.inbuffer[:s]
+ self.inbuffer = self.inbuffer[s:]
+ if DebugMode.RAW_IN in self.debug:
+ print("received packet(type %d):" % t, repr(d),
+ **self.debugopts)
+ return (t, d)
+ def send(self, b):
+ if not isinstance(b, bytes):
+ raise SftpInternalException("send not given byte sequence")
+ if DebugMode.RAW_OUT_STAT in self.debug:
+ print("sending packet of %d bytes" % len(b),
+ **self.debugopts)
+ if DebugMode.RAW_OUT in self.debug:
+ print("sending packet:", repr(b),
+ **self.debugopts)
+ self.connection.stdin.write(b)
+ def enqueueRequest(self, job):
+ if DebugMode.ENQUEUE in self.debug:
+ print("enqueue", job,
+ **self.debugopts)
+ if len(self.queue) == 0 and len(self.wantwrite) == 0:
+ self.poll.register(self.connection.stdin,
+ select.POLLOUT)
+ job.requestid = self.next_request_id()
+ self.queue.append(job)
+ def enqueueTask(self, task):
+ if DebugMode.ENQUEUE in self.debug:
+ print("enqueue", task, **self.debugopts)
+ if len(self.queue) == 0 and len(self.wantwrite) == 0:
+ self.poll.register(self.connection.stdin,
+ select.POLLOUT)
+ self.wantwrite.append(task)
+ def collect(self, who, command, collectortype, *collectorargs):
+ if DebugMode.LOCKS in self.debug:
+ print("collector", command, collectortype.__name__,
+ *collectorargs, **self.debugopts)
+ """Tell the (possibly to be generated) """
+ collectorid = (collectortype, collectorargs)
+ if not collectorid in self.collectors:
+ l = collectortype(*collectorargs)
+ self.collectors[collectorid] = l
+ l.start(self)
+ else:
+ l = self.collectors[collectorid]
+ l.childinfo(who, command)
+ def start(self, task):
+ task.start(self)
+ def dispatchanswer(self, answer):
+ task = answer.forr.task
+ try:
+ task.sftpanswer(answer)
+ except StopIteration:
+ orphanreqs = [ r
+ for r in self.requests.values()
+ if r.task == task ]
+ for r in orphanreqs:
+ r.done()
+ def readdata(self):
+ t,m = self.getpacket()
+ for answer in Answer.__subclasses__():
+ if t == answer.id:
+ break
+ else:
+ raise SftpUnexpectedAnswerException("Unknown answer type %d" % t, "")
+ id, m = ssh_getu32(m)
+ a = answer(m)
+ if DebugMode.COOKED_IN in self.debug:
+ print("got answer for request %d: %s" %
+ (id, str(a)), **self.debugopts)
+ if not id in self.requests:
+ raise SftpUnexpectedAnswerException(a, "unknown-id-%d" % id)
+ else:
+ a.forr = self.requests[id]
+ self.dispatchanswer(a)
+ def senddata(self):
+ if len(self.queue) == 0:
+ while len(self.wantwrite) > 0:
+ w = self.wantwrite.pop(0)
+ if len(self.wantwrite) == 0 and len(self.queue) == 0:
+ self.poll.unregister(self.connection.stdin)
+ w.writeready()
+ if len(self.queue) > 0:
+ request = self.queue.pop(0)
+ if len(self.queue) == 0 and len(self.wantwrite) == 0:
+ self.poll.unregister(self.connection.stdin)
+ if DebugMode.COOKED_OUT in self.debug:
+ print("sending request %d: %s" %
+ (request.requestid, str(request)),
+ **self.debugopts)
+ request.send(self)
+ def dispatch(self):
+ while self.requests or self.queue:
+ for (fd, event) in self.poll.poll():
+ if event == select.POLLIN:
+ self.readdata()
+ elif event == select.POLLHUP:
+ raise SftpStrangeException(
+ "Server disconnected unexpectedly"
+ " or ssh client process terminated")
+ elif event == select.POLLOUT:
+ self.senddata()
+ else:
+ raise SftpException("Unexpected event %d from poll" % event)
+
+class Dirlock(Collector):
+ def __init__(self, name):
+ super().__init__()
+ self.name = name
+ self.dirname = os.path.dirname(name)
+ self.queue = []
+ def start(self, connection):
+ super().start(connection)
+ if self.dirname and (self.name != self.dirname):
+ self.mode = "wait-for-parent"
+ self.connection.collect(self, 'waitingfor',
+ Dirlock, self.dirname)
+ else:
+ self.tellparent = False
+ self.mode = "wait-for-client"
+ self.isnew = False
+ def sftpanswer(self, a):
+ assert(self.mode == "creating")
+ if not isinstance(a, STATUS):
+ raise SftpUnexpectedAnswer(a, a.forr)
+ # Only one answer is expected:
+ a.forr.done()
+ if a.status == SSH_FX.OK:
+ self.mode = "exists"
+ self.isnew = True
+ self.releaseallqueued()
+ elif self.tellparent and a.status == SSH_FX.NO_SUCH_FILE:
+ self.mode = "wait-for-parent"
+ self.connection.collect(self, 'missing',
+ Dirlock, self.dirname)
+ else:
+ raise SftpException("Cannot create directory %s: %s" % (self.name, a))
+ def parentinfo(self, command):
+ assert(self.mode == "wait-for-parent")
+ if command == "createnew":
+ self.tellparent = False
+ self.isnew = True
+ self.createdir()
+ return
+ if command != "tryandtell" and command != "ready":
+ raise SftpInternalException(
+ "Unexpected parent info %s" %
+ command)
+ self.tellparent = command == "tryandtell"
+ if len(self.queue) > 0:
+ self.mode = "testing"
+ self.queue.pop(0).parentinfo("tryandtell")
+ else:
+ self.mode = "wait-for-client"
+ def childinfo(self, who, command):
+ if command == "waitingfor":
+ if self.mode == "exists":
+ if self.isnew:
+ who.parentinfo("createnew")
+ else:
+ who.parentinfo("ready")
+ elif self.mode == "wait-for-client":
+ self.mode = "testing"
+ who.parentinfo("tryandtell")
+ else:
+ self.queue.append(who)
+ elif command == "found":
+ assert(self.mode == "testing")
+ self.mode = "exists"
+ self.isnew = False
+ self.releaseallqueued()
+ elif command == "missing":
+ self.queue.append(who)
+ self.mode = "creating"
+ self.createdir()
+ else:
+ raise SftpInternalException(
+ "Unexpected child information: %s" %
+ command)
+ def createdir(self):
+ self.mode = "creating"
+ self.enqueueRequest(MKDIR(self.name))
+ def releaseallqueued(self):
+ if self.tellparent:
+ self.connection.collect(self, 'found',
+ Dirlock, self.dirname)
+ self.tellparent = False
+ if self.isnew:
+ command = "createnew"
+ else:
+ command = "ready"
+ # This assumes out mode cannot change any more:
+ while self.queue:
+ self.queue.pop(0).parentinfo(command)
+
+class Semaphore(Collector):
+ def __init__(self, name):
+ super().__init__()
+ self.name = name
+ self.queue = []
+ self.allowed = 10
+ def start(self, connection):
+ self.allowed = connection.semaphores[self.name]
+ def childinfo(self, who, command):
+ if command == "lock":
+ if self.allowed > 0:
+ self.allowed -= 1
+ who.parentinfo("unlock")
+ else:
+ self.queue.append(who)
+ elif command == "release":
+ if self.allowed == 0 and self.queue:
+ self.queue.pop(0).parentinfo("unlock")
+ else:
+ self.allowed += 1
+ else:
+ raise SftpInternalException("Semaphore.childinfo called with invalid command")
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-05 02:03:56 +0000