[New-bugs-announce] [issue29860] smtplib.py doesn't capitalize EHLO.

[Lord Anton Hvornum]

New submission from Lord Anton Hvornum:

```
  File "mail.py", line 9, in <module>
    smtp_server.starttls(context)
  File "/usr/lib/python3.6/smtplib.py", line 748, in starttls
    self.ehlo_or_helo_if_needed()
  File "/usr/lib/python3.6/smtplib.py", line 600, in ehlo_or_helo_if_needed
    (code, resp) = self.helo()
  File "/usr/lib/python3.6/smtplib.py", line 429, in helo
    (code, msg) = self.getreply()
  File "/usr/lib/python3.6/smtplib.py", line 393, in getreply
    raise SMTPServerDisconnected("Connection unexpectedly closed")
```

This happens due to the server expecting commands (like EHLO, STARTTLS) being strict upper-case. And when the SMTP command isn't, it drops us.

This is a rare edge case since most mail servers handles shady client data in numerous different ways (such as gmail never sending QUIT for instance).

I don't know of a work-around for this and the documentation states `EHLO` is being sent (https://docs.python.org/3/library/smtplib.html), so I guess the lib assumes that's the case as well.

----------
components: Library (Lib)
messages: 289886
nosy: Lord Anton Hvornum
priority: normal
severity: normal
status: open
title: smtplib.py doesn't capitalize EHLO.
versions: Python 3.6, Python 3.7

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue29860>
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