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|
=====================
Pre-approved postings
=====================
Messages can contain a pre-approval, which is used to bypass the message
approval queue. This has several use cases:
- A list administrator can send an emergency message to the mailing list from
an unregistered address, say if they are away from their normal email.
- An automated script can be programmed to send a message to an otherwise
moderated list.
In order to support this, a mailing list can be given a 'moderator password'
which is shared among all the administrators.
>>> mlist = create_list('_xtest@example.com')
>>> mlist.moderator_password = 'abcxyz'
The 'approved' rule determines whether the message contains the proper
approval or not.
>>> rule = config.rules['approved']
>>> print rule.name
approved
No approval
===========
If the message has no Approve or Approved header, then the rule does not
match.
>>> msg = message_from_string("""\
... From: aperson@example.com
...
... An important message.
... """)
>>> rule.check(mlist, msg, {})
False
If the message has an Approve or Approved header with a value that does not
match the moderator password, then the rule does not match. However, the
header is still removed.
>>> msg['Approve'] = '12345'
>>> rule.check(mlist, msg, {})
False
>>> print msg['approve']
None
>>> del msg['approve']
>>> msg['Approved'] = '12345'
>>> rule.check(mlist, msg, {})
False
>>> print msg['approved']
None
>>> del msg['approved']
Using an approval header
========================
If the moderator password is given in an Approve header, then the rule
matches, and the Approve header is stripped.
>>> msg['Approve'] = 'abcxyz'
>>> rule.check(mlist, msg, {})
True
>>> print msg['approve']
None
Similarly, for the Approved header.
>>> msg['Approved'] = 'abcxyz'
>>> rule.check(mlist, msg, {})
True
>>> print msg['approved']
None
Using a pseudo-header
=====================
Different mail user agents have varying degrees to which they support custom
headers like Approve and Approved. For this reason, Mailman also supports
using a 'pseudo-header', which is really just the first non-whitespace line in
the payload of the message. If this pseudo-header looks like a matching
Approve or Approved header, the message is similarly allowed to pass.
>>> msg = message_from_string("""\
... From: aperson@example.com
...
... Approve: abcxyz
... An important message.
... """)
>>> rule.check(mlist, msg, {})
True
The pseudo-header is removed.
>>> print msg.as_string()
From: aperson@example.com
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
<BLANKLINE>
Similarly for the Approved header.
>>> msg = message_from_string("""\
... From: aperson@example.com
...
... Approved: abcxyz
... An important message.
... """)
>>> rule.check(mlist, msg, {})
True
>>> print msg.as_string()
From: aperson@example.com
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
<BLANKLINE>
As before, a mismatch in the pseudo-header does not approve the message, but
the pseudo-header line is still removed.
>>> msg = message_from_string("""\
... From: aperson@example.com
...
... Approve: 123456
... An important message.
... """)
>>> rule.check(mlist, msg, {})
False
>>> print msg.as_string()
From: aperson@example.com
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
<BLANKLINE>
Similarly for the Approved header.
>>> msg = message_from_string("""\
... From: aperson@example.com
...
... Approved: 123456
... An important message.
... """)
>>> rule.check(mlist, msg, {})
False
>>> print msg.as_string()
From: aperson@example.com
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
<BLANKLINE>
MIME multipart support
======================
Mailman searches for the pseudo-header as the first non-whitespace line in the
first text/plain message part of the message. This allows the feature to be
used with MIME documents.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: application/x-ignore
...
... Approve: 123456
... The above line will be ignored.
...
... --AAA
... Content-Type: text/plain
...
... Approve: abcxyz
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
True
Like before, the pseudo-header is removed, but only from the text parts.
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Type: application/x-ignore
<BLANKLINE>
Approve: 123456
The above line will be ignored.
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
<BLANKLINE>
The same goes for the Approved message.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: application/x-ignore
...
... Approved: 123456
... The above line will be ignored.
...
... --AAA
... Content-Type: text/plain
...
... Approved: abcxyz
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
True
And the header is removed.
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Type: application/x-ignore
<BLANKLINE>
Approved: 123456
The above line will be ignored.
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
<BLANKLINE>
Here, the correct password is in the non-text/plain part, so it is ignored.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: application/x-ignore
...
... Approve: abcxyz
... The above line will be ignored.
...
... --AAA
... Content-Type: text/plain
...
... Approve: 123456
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
False
And yet the pseudo-header is still stripped.
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Type: application/x-ignore
<BLANKLINE>
Approve: abcxyz
The above line will be ignored.
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
As before, the same goes for the Approved header.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: application/x-ignore
...
... Approved: abcxyz
... The above line will be ignored.
...
... --AAA
... Content-Type: text/plain
...
... Approved: 123456
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
False
And the pseudo-header is removed.
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Type: application/x-ignore
<BLANKLINE>
Approved: abcxyz
The above line will be ignored.
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
Stripping text/html parts
=========================
Because some mail readers will include both a text/plain part and a text/html
alternative, the 'approved' rule has to search the alternatives and strip
anything that looks like an Approve or Approved headers.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: text/html
...
... <html>
... <head></head>
... <body>
... <b>Approved: abcxyz</b>
... <p>The above line will be ignored.
... </body>
... </html>
...
... --AAA
... Content-Type: text/plain
...
... Approved: abcxyz
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
True
And the header-like text in the text/html part was stripped.
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/html; charset="us-ascii"
<BLANKLINE>
<html>
<head></head>
<body>
<b></b>
<p>The above line will be ignored.
</body>
</html>
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
<BLANKLINE>
This is true even if the rule does not match.
>>> msg = message_from_string("""\
... From: aperson@example.com
... MIME-Version: 1.0
... Content-Type: multipart/mixed; boundary="AAA"
...
... --AAA
... Content-Type: text/html
...
... <html>
... <head></head>
... <body>
... <b>Approve: 123456</b>
... <p>The above line will be ignored.
... </body>
... </html>
...
... --AAA
... Content-Type: text/plain
...
... Approve: 123456
... An important message.
... --AAA--
... """)
>>> rule.check(mlist, msg, {})
False
>>> print msg.as_string()
From: aperson@example.com
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="AAA"
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/html; charset="us-ascii"
<BLANKLINE>
<html>
<head></head>
<body>
<b></b>
<p>The above line will be ignored.
</body>
</html>
<BLANKLINE>
--AAA
Content-Transfer-Encoding: 7bit
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
<BLANKLINE>
An important message.
--AAA--
<BLANKLINE>
|
