Question

I am trying to use ftps to upload file to our FTP server. Login is trivial and works:

from M2Crypto import ftpslib
ftp = ftpslib.FTP_TLS()
ftp.connect(host)
ftp.login(username, password)

as well as descending into directory

for dir in directory:
    ftp.cwd(dir)

However, when trying to retrieve directory content:

if directory_name not in ftp.nlst():
    ftp.mkd(directory_name)

I get 522 error:

File "/usr/lib/python2.5/ftplib.py", line 459, in nlst
  self.retrlines(cmd, files.append)
File "/usr/lib/python2.5/ftplib.py", line 407, in retrlines
  conn = self.transfercmd(cmd)
File "/usr/lib/python2.5/ftplib.py", line 356, in transfercmd
  return self.ntransfercmd(cmd, rest)[0]
File "/var/lib/python-support/python2.5/M2Crypto/ftpslib.py", line 86, in ntransfercmd
  conn, size = FTP.ntransfercmd(self, cmd, rest)
File "/usr/lib/python2.5/ftplib.py", line 327, in ntransfercmd
  resp = self.sendcmd(cmd)
File "/usr/lib/python2.5/ftplib.py", line 241, in sendcmd
  return self.getresp()
File "/usr/lib/python2.5/ftplib.py", line 216, in getresp
  raise error_perm, resp
ftplib.error_perm: 522 Data connections must be encrypted.

It seems TLS is used only for handshake, not for transfers.

It there a way to secure the transfer (I’d like to upload files using storbinary()) using M2Crypto? If not, what are other alternatives?

Answer 1

Solution is to explicitly call for protected transfer after login():

ftp.prot_p()