diff options
Diffstat (limited to 'paramiko/sftp_server.py')
| -rw-r--r-- | paramiko/sftp_server.py | 174 |
1 files changed, 89 insertions, 85 deletions
diff --git a/paramiko/sftp_server.py b/paramiko/sftp_server.py index 1833c2e..2d8d190 100644 --- a/paramiko/sftp_server.py +++ b/paramiko/sftp_server.py @@ -22,46 +22,55 @@ Server-mode SFTP support. import os import errno +import sys +from hashlib import md5, sha1 -from Crypto.Hash import MD5, SHA -from paramiko.common import * +from paramiko import util +from paramiko.sftp import BaseSFTP, Message, SFTP_FAILURE, \ + SFTP_PERMISSION_DENIED, SFTP_NO_SUCH_FILE +from paramiko.sftp_si import SFTPServerInterface +from paramiko.sftp_attr import SFTPAttributes +from paramiko.common import DEBUG +from paramiko.py3compat import long, string_types, bytes_types, b from paramiko.server import SubsystemHandler -from paramiko.sftp import * -from paramiko.sftp_si import * -from paramiko.sftp_attr import * # known hash algorithms for the "check-file" extension +from paramiko.sftp import CMD_HANDLE, SFTP_DESC, CMD_STATUS, SFTP_EOF, CMD_NAME, \ + SFTP_BAD_MESSAGE, CMD_EXTENDED_REPLY, SFTP_FLAG_READ, SFTP_FLAG_WRITE, \ + SFTP_FLAG_APPEND, SFTP_FLAG_CREATE, SFTP_FLAG_TRUNC, SFTP_FLAG_EXCL, \ + CMD_NAMES, CMD_OPEN, CMD_CLOSE, SFTP_OK, CMD_READ, CMD_DATA, CMD_WRITE, \ + CMD_REMOVE, CMD_RENAME, CMD_MKDIR, CMD_RMDIR, CMD_OPENDIR, CMD_READDIR, \ + CMD_STAT, CMD_ATTRS, CMD_LSTAT, CMD_FSTAT, CMD_SETSTAT, CMD_FSETSTAT, \ + CMD_READLINK, CMD_SYMLINK, CMD_REALPATH, CMD_EXTENDED, SFTP_OP_UNSUPPORTED + _hash_class = { - 'sha1': SHA, - 'md5': MD5, + 'sha1': sha1, + 'md5': md5, } class SFTPServer (BaseSFTP, SubsystemHandler): """ - Server-side SFTP subsystem support. Since this is a L{SubsystemHandler}, - it can be (and is meant to be) set as the handler for C{"sftp"} requests. - Use L{Transport.set_subsystem_handler} to activate this class. + Server-side SFTP subsystem support. Since this is a `.SubsystemHandler`, + it can be (and is meant to be) set as the handler for ``"sftp"`` requests. + Use `.Transport.set_subsystem_handler` to activate this class. """ def __init__(self, channel, name, server, sftp_si=SFTPServerInterface, *largs, **kwargs): """ The constructor for SFTPServer is meant to be called from within the - L{Transport} as a subsystem handler. C{server} and any additional + `.Transport` as a subsystem handler. ``server`` and any additional parameters or keyword parameters are passed from the original call to - L{Transport.set_subsystem_handler}. + `.Transport.set_subsystem_handler`. - @param channel: channel passed from the L{Transport}. - @type channel: L{Channel} - @param name: name of the requested subsystem. - @type name: str - @param server: the server object associated with this channel and - subsystem - @type server: L{ServerInterface} - @param sftp_si: a subclass of L{SFTPServerInterface} to use for handling - individual requests. - @type sftp_si: class + :param .Channel channel: channel passed from the `.Transport`. + :param str name: name of the requested subsystem. + :param .ServerInterface server: + the server object associated with this channel and subsystem + :param class sftp_si: + a subclass of `.SFTPServerInterface` to use for handling individual + requests. """ BaseSFTP.__init__(self) SubsystemHandler.__init__(self, channel, name, server) @@ -70,17 +79,17 @@ class SFTPServer (BaseSFTP, SubsystemHandler): self.ultra_debug = transport.get_hexdump() self.next_handle = 1 # map of handle-string to SFTPHandle for files & folders: - self.file_table = { } - self.folder_table = { } + self.file_table = {} + self.folder_table = {} self.server = sftp_si(server, *largs, **kwargs) - + def _log(self, level, msg): if issubclass(type(msg), list): for m in msg: super(SFTPServer, self)._log(level, "[chan " + self.sock.get_name() + "] " + m) else: super(SFTPServer, self)._log(level, "[chan " + self.sock.get_name() + "] " + msg) - + def start_subsystem(self, name, transport, channel): self.sock = channel self._log(DEBUG, 'Started sftp server on channel %s' % repr(channel)) @@ -92,7 +101,7 @@ class SFTPServer (BaseSFTP, SubsystemHandler): except EOFError: self._log(DEBUG, 'EOF -- end of session') return - except Exception, e: + except Exception as e: self._log(DEBUG, 'Exception on channel: ' + str(e)) self._log(DEBUG, util.tb_strings()) return @@ -100,7 +109,7 @@ class SFTPServer (BaseSFTP, SubsystemHandler): request_number = msg.get_int() try: self._process(t, request_number, msg) - except Exception, e: + except Exception as e: self._log(DEBUG, 'Exception in server processing: ' + str(e)) self._log(DEBUG, util.tb_strings()) # send some kind of failure message, at least @@ -113,23 +122,21 @@ class SFTPServer (BaseSFTP, SubsystemHandler): self.server.session_ended() super(SFTPServer, self).finish_subsystem() # close any file handles that were left open (so we can return them to the OS quickly) - for f in self.file_table.itervalues(): + for f in self.file_table.values(): f.close() - for f in self.folder_table.itervalues(): + for f in self.folder_table.values(): f.close() self.file_table = {} self.folder_table = {} def convert_errno(e): """ - Convert an errno value (as from an C{OSError} or C{IOError}) into a + Convert an errno value (as from an ``OSError`` or ``IOError``) into a standard SFTP result code. This is a convenience function for trapping exceptions in server code and returning an appropriate result. - @param e: an errno code, as from C{OSError.errno}. - @type e: int - @return: an SFTP error code like L{SFTP_NO_SUCH_FILE}. - @rtype: int + :param int e: an errno code, as from ``OSError.errno``. + :return: an `int` SFTP error code like ``SFTP_NO_SUCH_FILE``. """ if e == errno.EACCES: # permission denied @@ -144,18 +151,16 @@ class SFTPServer (BaseSFTP, SubsystemHandler): def set_file_attr(filename, attr): """ Change a file's attributes on the local filesystem. The contents of - C{attr} are used to change the permissions, owner, group ownership, + ``attr`` are used to change the permissions, owner, group ownership, and/or modification & access time of the file, depending on which - attributes are present in C{attr}. + attributes are present in ``attr``. This is meant to be a handy helper function for translating SFTP file requests into local file operations. - - @param filename: name of the file to alter (should usually be an - absolute path). - @type filename: str - @param attr: attributes to change. - @type attr: L{SFTPAttributes} + + :param str filename: + name of the file to alter (should usually be an absolute path). + :param .SFTPAttributes attr: attributes to change. """ if sys.platform != 'win32': # mode operations are meaningless on win32 @@ -166,35 +171,34 @@ class SFTPServer (BaseSFTP, SubsystemHandler): if attr._flags & attr.FLAG_AMTIME: os.utime(filename, (attr.st_atime, attr.st_mtime)) if attr._flags & attr.FLAG_SIZE: - open(filename, 'w+').truncate(attr.st_size) + with open(filename, 'w+') as f: + f.truncate(attr.st_size) set_file_attr = staticmethod(set_file_attr) - ### internals... - def _response(self, request_number, t, *arg): msg = Message() msg.add_int(request_number) for item in arg: - if type(item) is int: - msg.add_int(item) - elif type(item) is long: + if isinstance(item, long): msg.add_int64(item) - elif type(item) is str: + elif isinstance(item, int): + msg.add_int(item) + elif isinstance(item, (string_types, bytes_types)): msg.add_string(item) elif type(item) is SFTPAttributes: item._pack(msg) else: raise Exception('unknown type for ' + repr(item) + ' type ' + repr(type(item))) - self._send_packet(t, str(msg)) + self._send_packet(t, msg) def _send_handle_response(self, request_number, handle, folder=False): if not issubclass(type(handle), SFTPHandle): # must be error code self._send_status(request_number, handle) return - handle._set_name('hx%d' % self.next_handle) + handle._set_name(b('hx%d' % self.next_handle)) self.next_handle += 1 if folder: self.folder_table[handle._get_name()] = handle @@ -232,16 +236,16 @@ class SFTPServer (BaseSFTP, SubsystemHandler): msg.add_int(len(flist)) for attr in flist: msg.add_string(attr.filename) - msg.add_string(str(attr)) + msg.add_string(attr) attr._pack(msg) - self._send_packet(CMD_NAME, str(msg)) + self._send_packet(CMD_NAME, msg) def _check_file(self, request_number, msg): # this extension actually comes from v6 protocol, but since it's an # extension, i feel like we can reasonably support it backported. # it's very useful for verifying uploaded files or checking for # rsync-like differences between local and remote files. - handle = msg.get_string() + handle = msg.get_binary() alg_list = msg.get_list() start = msg.get_int64() length = msg.get_int64() @@ -270,17 +274,17 @@ class SFTPServer (BaseSFTP, SubsystemHandler): self._send_status(request_number, SFTP_FAILURE, 'Block size too small') return - sum_out = '' + sum_out = bytes() offset = start while offset < start + length: blocklen = min(block_size, start + length - offset) # don't try to read more than about 64KB at a time chunklen = min(blocklen, 65536) count = 0 - hash_obj = alg.new() + hash_obj = alg() while count < blocklen: data = f.read(offset, chunklen) - if not type(data) is str: + if not isinstance(data, bytes_types): self._send_status(request_number, data, 'Unable to hash file') return hash_obj.update(data) @@ -293,10 +297,10 @@ class SFTPServer (BaseSFTP, SubsystemHandler): msg.add_string('check-file') msg.add_string(algname) msg.add_bytes(sum_out) - self._send_packet(CMD_EXTENDED_REPLY, str(msg)) - + self._send_packet(CMD_EXTENDED_REPLY, msg) + def _convert_pflags(self, pflags): - "convert SFTP-style open() flags to python's os.open() flags" + """convert SFTP-style open() flags to Python's os.open() flags""" if (pflags & SFTP_FLAG_READ) and (pflags & SFTP_FLAG_WRITE): flags = os.O_RDWR elif pflags & SFTP_FLAG_WRITE: @@ -316,12 +320,12 @@ class SFTPServer (BaseSFTP, SubsystemHandler): def _process(self, t, request_number, msg): self._log(DEBUG, 'Request: %s' % CMD_NAMES[t]) if t == CMD_OPEN: - path = msg.get_string() + path = msg.get_text() flags = self._convert_pflags(msg.get_int()) attr = SFTPAttributes._from_msg(msg) self._send_handle_response(request_number, self.server.open(path, flags, attr)) elif t == CMD_CLOSE: - handle = msg.get_string() + handle = msg.get_binary() if handle in self.folder_table: del self.folder_table[handle] self._send_status(request_number, SFTP_OK) @@ -333,14 +337,14 @@ class SFTPServer (BaseSFTP, SubsystemHandler): return self._send_status(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') elif t == CMD_READ: - handle = msg.get_string() + handle = msg.get_binary() offset = msg.get_int64() length = msg.get_int() if handle not in self.file_table: self._send_status(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') return data = self.file_table[handle].read(offset, length) - if type(data) is str: + if isinstance(data, (bytes_types, string_types)): if len(data) == 0: self._send_status(request_number, SFTP_EOF) else: @@ -348,54 +352,54 @@ class SFTPServer (BaseSFTP, SubsystemHandler): else: self._send_status(request_number, data) elif t == CMD_WRITE: - handle = msg.get_string() + handle = msg.get_binary() offset = msg.get_int64() - data = msg.get_string() + data = msg.get_binary() if handle not in self.file_table: self._send_status(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') return self._send_status(request_number, self.file_table[handle].write(offset, data)) elif t == CMD_REMOVE: - path = msg.get_string() + path = msg.get_text() self._send_status(request_number, self.server.remove(path)) elif t == CMD_RENAME: - oldpath = msg.get_string() - newpath = msg.get_string() + oldpath = msg.get_text() + newpath = msg.get_text() self._send_status(request_number, self.server.rename(oldpath, newpath)) elif t == CMD_MKDIR: - path = msg.get_string() + path = msg.get_text() attr = SFTPAttributes._from_msg(msg) self._send_status(request_number, self.server.mkdir(path, attr)) elif t == CMD_RMDIR: - path = msg.get_string() + path = msg.get_text() self._send_status(request_number, self.server.rmdir(path)) elif t == CMD_OPENDIR: - path = msg.get_string() + path = msg.get_text() self._open_folder(request_number, path) return elif t == CMD_READDIR: - handle = msg.get_string() + handle = msg.get_binary() if handle not in self.folder_table: self._send_status(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') return folder = self.folder_table[handle] self._read_folder(request_number, folder) elif t == CMD_STAT: - path = msg.get_string() + path = msg.get_text() resp = self.server.stat(path) if issubclass(type(resp), SFTPAttributes): self._response(request_number, CMD_ATTRS, resp) else: self._send_status(request_number, resp) elif t == CMD_LSTAT: - path = msg.get_string() + path = msg.get_text() resp = self.server.lstat(path) if issubclass(type(resp), SFTPAttributes): self._response(request_number, CMD_ATTRS, resp) else: self._send_status(request_number, resp) elif t == CMD_FSTAT: - handle = msg.get_string() + handle = msg.get_binary() if handle not in self.file_table: self._send_status(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') return @@ -405,34 +409,34 @@ class SFTPServer (BaseSFTP, SubsystemHandler): else: self._send_status(request_number, resp) elif t == CMD_SETSTAT: - path = msg.get_string() + path = msg.get_text() attr = SFTPAttributes._from_msg(msg) self._send_status(request_number, self.server.chattr(path, attr)) elif t == CMD_FSETSTAT: - handle = msg.get_string() + handle = msg.get_binary() attr = SFTPAttributes._from_msg(msg) if handle not in self.file_table: self._response(request_number, SFTP_BAD_MESSAGE, 'Invalid handle') return self._send_status(request_number, self.file_table[handle].chattr(attr)) elif t == CMD_READLINK: - path = msg.get_string() + path = msg.get_text() resp = self.server.readlink(path) - if type(resp) is str: + if isinstance(resp, (bytes_types, string_types)): self._response(request_number, CMD_NAME, 1, resp, '', SFTPAttributes()) else: self._send_status(request_number, resp) elif t == CMD_SYMLINK: # the sftp 2 draft is incorrect here! path always follows target_path - target_path = msg.get_string() - path = msg.get_string() + target_path = msg.get_text() + path = msg.get_text() self._send_status(request_number, self.server.symlink(target_path, path)) elif t == CMD_REALPATH: - path = msg.get_string() + path = msg.get_text() rpath = self.server.canonicalize(path) self._response(request_number, CMD_NAME, 1, rpath, '', SFTPAttributes()) elif t == CMD_EXTENDED: - tag = msg.get_string() + tag = msg.get_text() if tag == 'check-file': self._check_file(request_number, msg) else: |