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9fab6a1 May 15, 2015
James Bardin version 0.10.2
@remram44 @jtriley @dancras @JMSwag @dguerri @SuperGod
471 lines (411 sloc) 15.9 KB
# scp.py
# Copyright (C) 2008 James Bardin <j.bardin@gmail.com>
"""
Utilities for sending files over ssh using the scp1 protocol.
"""
__version__ = '0.10.2'
import locale
import os
import re
from socket import timeout as SocketTimeout
# this is quote from the shlex module, added in py3.3
_find_unsafe = re.compile(br'[^\w@%+=:,./~-]').search
def _sh_quote(s):
"""Return a shell-escaped version of the string `s`."""
if not s:
return b""
if _find_unsafe(s) is None:
return s
# use single quotes, and put single quotes into double quotes
# the string $'b is then quoted as '$'"'"'b'
return b"'" + s.replace(b"'", b"'\"'\"'") + b"'"
# Unicode conversion functions; assume UTF-8
def asbytes(s):
"""Turns unicode into bytes, if needed.
Assumes UTF-8.
"""
if isinstance(s, bytes):
return s
else:
return s.encode('utf-8')
def asunicode(s):
"""Turns bytes into unicode, if needed.
Uses UTF-8.
"""
if isinstance(s, bytes):
return s.decode('utf-8', 'replace')
else:
return s
# os.path.sep is unicode on Python 3, no matter the platform
bytes_sep = asbytes(os.path.sep)
# Unicode conversion function for Windows
# Used to convert local paths if the local machine is Windows
def asunicode_win(s):
"""Turns bytes into unicode, if needed.
"""
if isinstance(s, bytes):
return s.decode(locale.getpreferredencoding())
else:
return s
class SCPClient(object):
"""
An scp1 implementation, compatible with openssh scp.
Raises SCPException for all transport related errors. Local filesystem
and OS errors pass through.
Main public methods are .put and .get
The get method is controlled by the remote scp instance, and behaves
accordingly. This means that symlinks are resolved, and the transfer is
halted after too many levels of symlinks are detected.
The put method uses os.walk for recursion, and sends files accordingly.
Since scp doesn't support symlinks, we send file symlinks as the file
(matching scp behaviour), but we make no attempt at symlinked directories.
"""
def __init__(self, transport, buff_size=16384, socket_timeout=5.0,
progress=None, sanitize=_sh_quote):
"""
Create an scp1 client.
@param transport: an existing paramiko L{Transport}
@type transport: L{Transport}
@param buff_size: size of the scp send buffer.
@type buff_size: int
@param socket_timeout: channel socket timeout in seconds
@type socket_timeout: float
@param progress: callback - called with (filename, size, sent) during
transfers
@param sanitize: function - called with filename, should return
safe or escaped string. Uses _sh_quote by default.
@type progress: function(string, int, int)
"""
self.transport = transport
self.buff_size = buff_size
self.socket_timeout = socket_timeout
self.channel = None
self.preserve_times = False
self._progress = progress
self._recv_dir = b''
self._rename = False
self._utime = None
self.sanitize = sanitize
self._dirtimes = {}
def __enter__(self):
self.channel = self._open()
return self
def __exit__(self, type, value, traceback):
self.close()
def put(self, files, remote_path=b'.',
recursive=False, preserve_times=False):
"""
Transfer files to remote host.
@param files: A single path, or a list of paths to be transfered.
recursive must be True to transfer directories.
@type files: string OR list of strings
@param remote_path: path in which to receive the files on the remote
host. defaults to '.'
@type remote_path: str
@param recursive: transfer files and directories recursively
@type recursive: bool
@param preserve_times: preserve mtime and atime of transfered files
and directories.
@type preserve_times: bool
"""
self.preserve_times = preserve_times
self.channel = self._open()
self._pushed = 0
self.channel.settimeout(self.socket_timeout)
scp_command = (b'scp -t ', b'scp -r -t ')[recursive]
self.channel.exec_command(scp_command +
self.sanitize(asbytes(remote_path)))
self._recv_confirm()
if not isinstance(files, (list, tuple)):
files = [files]
if recursive:
self._send_recursive(files)
else:
self._send_files(files)
self.close()
def get(self, remote_path, local_path='',
recursive=False, preserve_times=False):
"""
Transfer files from remote host to localhost
@param remote_path: path to retreive from remote host. since this is
evaluated by scp on the remote host, shell wildcards and
environment variables may be used.
@type remote_path: str
@param local_path: path in which to receive files locally
@type local_path: str
@param recursive: transfer files and directories recursively
@type recursive: bool
@param preserve_times: preserve mtime and atime of transfered files
and directories.
@type preserve_times: bool
"""
if not isinstance(remote_path, (list, tuple)):
remote_path = [remote_path]
remote_path = [self.sanitize(asbytes(r)) for r in remote_path]
self._recv_dir = local_path or os.getcwd()
self._rename = (len(remote_path) == 1 and
not os.path.isdir(os.path.abspath(local_path)))
if len(remote_path) > 1:
if not os.path.exists(self._recv_dir):
raise SCPException("Local path '%s' does not exist" %
asunicode(self._recv_dir))
elif not os.path.isdir(self._recv_dir):
raise SCPException("Local path '%s' is not a directory" %
asunicode(self._recv_dir))
rcsv = (b'', b' -r')[recursive]
prsv = (b'', b' -p')[preserve_times]
self.channel = self._open()
self._pushed = 0
self.channel.settimeout(self.socket_timeout)
self.channel.exec_command(b"scp" +
rcsv +
prsv +
b" -f " +
b' '.join(remote_path))
self._recv_all()
self.close()
def _open(self):
"""open a scp channel"""
if self.channel is None:
self.channel = self.transport.open_session()
return self.channel
def close(self):
"""close scp channel"""
if self.channel is not None:
self.channel.close()
self.channel = None
def _read_stats(self, name):
"""return just the file stats needed for scp"""
if os.name == 'nt':
name = asunicode(name)
stats = os.stat(name)
mode = oct(stats.st_mode)[-4:]
size = stats.st_size
atime = int(stats.st_atime)
mtime = int(stats.st_mtime)
return (mode, size, mtime, atime)
def _send_files(self, files):
for name in files:
basename = asbytes(os.path.basename(name))
(mode, size, mtime, atime) = self._read_stats(name)
if self.preserve_times:
self._send_time(mtime, atime)
file_hdl = open(name, 'rb')
# The protocol can't handle \n in the filename.
# Quote them as the control sequence \^J for now,
# which is how openssh handles it.
self.channel.sendall(("C%s %d " % (mode, size)).encode('ascii') +
basename.replace(b'\n', b'\\^J') + b"\n")
self._recv_confirm()
file_pos = 0
if self._progress:
if size == 0:
# avoid divide-by-zero
self._progress(basename, 1, 1)
else:
self._progress(basename, size, 0)
buff_size = self.buff_size
chan = self.channel
while file_pos < size:
chan.sendall(file_hdl.read(buff_size))
file_pos = file_hdl.tell()
if self._progress:
self._progress(basename, size, file_pos)
chan.sendall('\x00')
file_hdl.close()
self._recv_confirm()
def _chdir(self, from_dir, to_dir):
# Pop until we're one level up from our next push.
# Push *once* into to_dir.
# This is dependent on the depth-first traversal from os.walk
# add path.sep to each when checking the prefix, so we can use
# path.dirname after
common = os.path.commonprefix([from_dir + bytes_sep,
to_dir + bytes_sep])
# now take the dirname, since commonprefix is character based,
# and we either have a seperator, or a partial name
common = os.path.dirname(common)
cur_dir = from_dir.rstrip(bytes_sep)
while cur_dir != common:
cur_dir = os.path.split(cur_dir)[0]
self._send_popd()
# now we're in our common base directory, so on
self._send_pushd(to_dir)
def _send_recursive(self, files):
for base in files:
if not os.path.isdir(base):
# filename mixed into the bunch
self._send_files([base])
continue
last_dir = asbytes(base)
for root, dirs, fls in os.walk(base):
self._chdir(last_dir, asbytes(root))
self._send_files([os.path.join(root, f) for f in fls])
last_dir = asbytes(root)
# back out of the directory
while self._pushed > 0:
self._send_popd()
def _send_pushd(self, directory):
(mode, size, mtime, atime) = self._read_stats(directory)
basename = asbytes(os.path.basename(directory))
if self.preserve_times:
self._send_time(mtime, atime)
self.channel.sendall(('D%s 0 ' % mode).encode('ascii') +
basename.replace(b'\n', b'\\^J') + b'\n')
self._recv_confirm()
self._pushed += 1
def _send_popd(self):
self.channel.sendall('E\n')
self._recv_confirm()
self._pushed -= 1
def _send_time(self, mtime, atime):
self.channel.sendall(('T%d 0 %d 0\n' % (mtime, atime)).encode('ascii'))
self._recv_confirm()
def _recv_confirm(self):
# read scp response
msg = b''
try:
msg = self.channel.recv(512)
except SocketTimeout:
raise SCPException('Timout waiting for scp response')
# slice off the first byte, so this compare will work in py2 and py3
if msg and msg[0:1] == b'\x00':
return
elif msg and msg[0:1] == b'\x01':
raise SCPException(asunicode(msg[1:]))
elif self.channel.recv_stderr_ready():
msg = self.channel.recv_stderr(512)
raise SCPException(asunicode(msg))
elif not msg:
raise SCPException('No response from server')
else:
raise SCPException('Invalid response from server', msg)
def _recv_all(self):
# loop over scp commands, and receive as necessary
command = {b'C': self._recv_file,
b'T': self._set_time,
b'D': self._recv_pushd,
b'E': self._recv_popd}
while not self.channel.closed:
# wait for command as long as we're open
self.channel.sendall('\x00')
msg = self.channel.recv(1024)
if not msg: # chan closed while recving
break
assert msg[-1:] == b'\n'
msg = msg[:-1]
code = msg[0:1]
try:
command[code](msg[1:])
except KeyError:
raise SCPException(asunicode(msg[1:]))
# directory times can't be set until we're done writing files
self._set_dirtimes()
def _set_time(self, cmd):
try:
times = cmd.split(b' ')
mtime = int(times[0])
atime = int(times[2]) or mtime
except:
self.channel.send(b'\x01')
raise SCPException('Bad time format')
# save for later
self._utime = (atime, mtime)
def _recv_file(self, cmd):
chan = self.channel
parts = cmd.strip().split(b' ', 2)
try:
mode = int(parts[0], 8)
size = int(parts[1])
if self._rename:
path = self._recv_dir
self._rename = False
elif os.name == 'nt':
path = os.path.join(asunicode_win(self._recv_dir),
parts[2].decode('utf-8'))
else:
path = os.path.join(asbytes(self._recv_dir),
parts[2])
except:
chan.send('\x01')
chan.close()
raise SCPException('Bad file format')
try:
file_hdl = open(path, 'wb')
except IOError as e:
chan.send(b'\x01' + str(e).encode('utf-8'))
chan.close()
raise
if self._progress:
if size == 0:
# avoid divide-by-zero
self._progress(path, 1, 1)
else:
self._progress(path, size, 0)
buff_size = self.buff_size
pos = 0
chan.send(b'\x00')
try:
while pos < size:
# we have to make sure we don't read the final byte
if size - pos <= buff_size:
buff_size = size - pos
file_hdl.write(chan.recv(buff_size))
pos = file_hdl.tell()
if self._progress:
self._progress(path, size, pos)
msg = chan.recv(512)
if msg and msg[0:1] != b'\x00':
raise SCPException(asunicode(msg[1:]))
except SocketTimeout:
chan.close()
raise SCPException('Error receiving, socket.timeout')
file_hdl.truncate()
try:
os.utime(path, self._utime)
self._utime = None
os.chmod(path, mode)
# should we notify the other end?
finally:
file_hdl.close()
# '\x00' confirmation sent in _recv_all
def _recv_pushd(self, cmd):
parts = cmd.split(b' ', 2)
try:
mode = int(parts[0], 8)
if self._rename:
path = self._recv_dir
self._rename = False
elif os.name == 'nt':
path = os.path.join(asunicode_win(self._recv_dir),
parts[2].decode('utf-8'))
else:
path = os.path.join(asbytes(self._recv_dir),
parts[2])
except:
self.channel.send(b'\x01')
raise SCPException('Bad directory format')
try:
if not os.path.exists(path):
os.mkdir(path, mode)
elif os.path.isdir(path):
os.chmod(path, mode)
else:
raise SCPException('%s: Not a directory' % path)
self._dirtimes[path] = (self._utime)
self._utime = None
self._recv_dir = path
except (OSError, SCPException) as e:
self.channel.send(b'\x01' + asbytes(str(e)))
raise
def _recv_popd(self, *cmd):
self._recv_dir = os.path.split(self._recv_dir)[0]
def _set_dirtimes(self):
try:
for d in self._dirtimes:
os.utime(d, self._dirtimes[d])
finally:
self._dirtimes = {}
class SCPException(Exception):
"""SCP exception class"""
pass