paramiko.sftp

Source Code for Module paramiko.sftp

+ 1 # Copyright (C) 2003-2007 Robey Pointer <robey@lag.net> + 2 # + 3 # This file is part of paramiko. + 4 # + 5 # Paramiko is free software; you can redistribute it and/or modify it under the + 6 # terms of the GNU Lesser General Public License as published by the Free + 7 # Software Foundation; either version 2.1 of the License, or (at your option) + 8 # any later version. + 9 # + 10 # Paramiko is distrubuted in the hope that it will be useful, but WITHOUT ANY + 11 # WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR + 12 # A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more + 13 # details. + 14 # + 15 # You should have received a copy of the GNU Lesser General Public License + 16 # along with Paramiko; if not, write to the Free Software Foundation, Inc., + 17 # 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + 18 + 19 import select + 20 import socket + 21 import struct + 22 + 23 from paramiko.common import * + 24 from paramiko import util + 25 from paramiko.channel import Channel + 26 from paramiko.message import Message + 27 + 28 + 29 CMD_INIT, CMD_VERSION, CMD_OPEN, CMD_CLOSE, CMD_READ, CMD_WRITE, CMD_LSTAT, CMD_FSTAT, \ + 30 CMD_SETSTAT, CMD_FSETSTAT, CMD_OPENDIR, CMD_READDIR, CMD_REMOVE, CMD_MKDIR, \ + 31 CMD_RMDIR, CMD_REALPATH, CMD_STAT, CMD_RENAME, CMD_READLINK, CMD_SYMLINK \ + 32 = range(1, 21) + 33 CMD_STATUS, CMD_HANDLE, CMD_DATA, CMD_NAME, CMD_ATTRS = range(101, 106) + 34 CMD_EXTENDED, CMD_EXTENDED_REPLY = range(200, 202) + 35 + 36 SFTP_OK = 0 + 37 SFTP_EOF, SFTP_NO_SUCH_FILE, SFTP_PERMISSION_DENIED, SFTP_FAILURE, SFTP_BAD_MESSAGE, \ + 38 SFTP_NO_CONNECTION, SFTP_CONNECTION_LOST, SFTP_OP_UNSUPPORTED = range(1, 9) + 39 + 40 SFTP_DESC = [ 'Success', + 41 'End of file', + 42 'No such file', + 43 'Permission denied', + 44 'Failure', + 45 'Bad message', + 46 'No connection', + 47 'Connection lost', + 48 'Operation unsupported' ] + 49 + 50 SFTP_FLAG_READ = 0x1 + 51 SFTP_FLAG_WRITE = 0x2 + 52 SFTP_FLAG_APPEND = 0x4 + 53 SFTP_FLAG_CREATE = 0x8 + 54 SFTP_FLAG_TRUNC = 0x10 + 55 SFTP_FLAG_EXCL = 0x20 + 56 + 57 _VERSION = 3 + 58 + 59 + 60 # for debugging + 61 CMD_NAMES = { + 62 CMD_INIT: 'init', + 63 CMD_VERSION: 'version', + 64 CMD_OPEN: 'open', + 65 CMD_CLOSE: 'close', + 66 CMD_READ: 'read', + 67 CMD_WRITE: 'write', + 68 CMD_LSTAT: 'lstat', + 69 CMD_FSTAT: 'fstat', + 70 CMD_SETSTAT: 'setstat', + 71 CMD_FSETSTAT: 'fsetstat', + 72 CMD_OPENDIR: 'opendir', + 73 CMD_READDIR: 'readdir', + 74 CMD_REMOVE: 'remove', + 75 CMD_MKDIR: 'mkdir', + 76 CMD_RMDIR: 'rmdir', + 77 CMD_REALPATH: 'realpath', + 78 CMD_STAT: 'stat', + 79 CMD_RENAME: 'rename', + 80 CMD_READLINK: 'readlink', + 81 CMD_SYMLINK: 'symlink', + 82 CMD_STATUS: 'status', + 83 CMD_HANDLE: 'handle', + 84 CMD_DATA: 'data', + 85 CMD_NAME: 'name', + 86 CMD_ATTRS: 'attrs', + 87 CMD_EXTENDED: 'extended', + 88 CMD_EXTENDED_REPLY: 'extended_reply' + 89 } + 90 + 91 +

92 -class SFTPError (Exception): +

93 pass +

94 + 95 +

96 -class BaseSFTP (object): +

97 - def __init__(self): +

98 self.logger = util.get_logger('paramiko.sftp') + 99 self.sock = None +100 self.ultra_debug = False +

101 +102 +103 ### internals... +104 +105 +

106 - def _send_version(self): +

107 self._send_packet(CMD_INIT, struct.pack('>I', _VERSION)) +108 t, data = self._read_packet() +109 if t != CMD_VERSION: +110 raise SFTPError('Incompatible sftp protocol') +111 version = struct.unpack('>I', data[:4])[0] +112 # if version != _VERSION: +113 # raise SFTPError('Incompatible sftp protocol') +114 return version +

115 +

116 - def _send_server_version(self): +

117 # winscp will freak out if the server sends version info before the +118 # client finishes sending INIT. +119 t, data = self._read_packet() +120 if t != CMD_INIT: +121 raise SFTPError('Incompatible sftp protocol') +122 version = struct.unpack('>I', data[:4])[0] +123 # advertise that we support "check-file" +124 extension_pairs = [ 'check-file', 'md5,sha1' ] +125 msg = Message() +126 msg.add_int(_VERSION) +127 msg.add(*extension_pairs) +128 self._send_packet(CMD_VERSION, str(msg)) +129 return version +

130 +

131 - def _log(self, level, msg, *args): +

132 self.logger.log(level, msg, *args) +

133 +

134 - def _write_all(self, out): +

135 while len(out) > 0: +136 n = self.sock.send(out) +137 if n <= 0: +138 raise EOFError() +139 if n == len(out): +140 return +141 out = out[n:] +142 return +

143 +

144 - def _read_all(self, n): +

145 out = '' +146 while n > 0: +147 if isinstance(self.sock, socket.socket): +148 # sometimes sftp is used directly over a socket instead of +149 # through a paramiko channel. in this case, check periodically +150 # if the socket is closed. (for some reason, recv() won't ever +151 # return or raise an exception, but calling select on a closed +152 # socket will.) +153 while True: +154 read, write, err = select.select([ self.sock ], [], [], 0.1) +155 if len(read) > 0: +156 x = self.sock.recv(n) +157 break +158 else: +159 x = self.sock.recv(n) +160 +161 if len(x) == 0: +162 raise EOFError() +163 out += x +164 n -= len(x) +165 return out +

166 +

167 - def _send_packet(self, t, packet): +

168 #self._log(DEBUG2, 'write: %s (len=%d)' % (CMD_NAMES.get(t, '0x%02x' % t), len(packet))) +169 out = struct.pack('>I', len(packet) + 1) + chr(t) + packet +170 if self.ultra_debug: +171 self._log(DEBUG, util.format_binary(out, 'OUT: ')) +172 self._write_all(out) +

173 +

174 - def _read_packet(self): +

175 x = self._read_all(4) +176 # most sftp servers won't accept packets larger than about 32k, so +177 # anything with the high byte set (> 16MB) is just garbage. +178 if x[0] != '\x00': +179 raise SFTPError('Garbage packet received') +180 size = struct.unpack('>I', x)[0] +181 data = self._read_all(size) +182 if self.ultra_debug: +183 self._log(DEBUG, util.format_binary(data, 'IN: ')); +184 if size > 0: +185 t = ord(data[0]) +186 #self._log(DEBUG2, 'read: %s (len=%d)' % (CMD_NAMES.get(t), '0x%02x' % t, len(data)-1)) +187 return t, data[1:] +188 return 0, '' +

189 +