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B315 - Fix for sending encrypted response to buffered unencrypted cmd

Open danifus opened this issue 5 years ago • 4 comments

danifus avatar Mar 06 '20 06:03 danifus

Coverage Status

Coverage remained the same at ?% when pulling f1a3b6eac7d4986f8b07b0c33d873a3a41f23a11 on danifus:b315 into 1122c7df99fe294be29b6093bcf538843d8e2653 on giampaolo:master.

coveralls avatar Mar 06 '20 06:03 coveralls

Please explain =)

giampaolo avatar Mar 06 '20 10:03 giampaolo

I was having a look through the issues and found #315 which was a bit old and you had asked for a python test demonstrating the issue and thought I would have a go.

The summary is:

  • Send b"AUTH TLS\r\nNOOP\r\n" in a single client.sock.sendall() call.
  • AUTH TLS\r\nNOOP\r\n is now in the server buffer
  • found_terminator() returns AUTH TLS, NOOP is still in the buffer.
  • tls socket is established
  • server returns 234 AUTH TLS successful.
  • found_terminator() returns NOOP
  • server returns 200 I successfully done nothin'. over the tls connection.

https://github.com/giampaolo/pyftpdlib/pull/523/commits/8b2d2ec476a767bf2ca0d5ab242320c8973b77fc#diff-3f8de7cee164531b3e8fa45af77f4626R355-R385 sets this up and tests that nothing is returned after the AUTH response (provided that is the way you want to go, as opposed to raising an error).

danifus avatar Mar 06 '20 11:03 danifus

The fix just clears out asynchat inbound buffer in ftp_AUTH if a secure connection is being established. Not sure that is the proper fix and happy for you to choose a different approach

danifus avatar Mar 06 '20 11:03 danifus