Match Field - Multi Line Regex for To Field

[Joe Botha]

Hi

Trying to use a What Object with Match Field regex. I believe some mail clients sent the To field in more than one line.

It seems Perl has a /s modifier which lets lets . match newline - but I can't seem to use /s in the pmg config interface (Test String fails).

Do you have advice for writing a regex that would match things in the To field of an email which spans multiple lines?

 

[Stoiko Ivanov]

Could you share such an email (the complete mail with headers in a code-block)
maybe we can find something fitting.

 

[Joe Botha]

 

[Joe Botha]

Hi. Does that screenshot help?

Fairly easy to reproduce, just send a mail with two addresses in the To field using Apple / macOS mail app.

To create the above I saved the mail to a file with mutt, and then did a: 'cat -A filename'

 

[Joe Botha]

The regex I'm trying to use is: (support@.*){2,}

Stop people from emailing more than one support@ account - don't email multiple ticketing systems at once.

 

[Joe Botha]

 

[Joe Botha]

Hi, side note: would be great to also stop people from sending:

To: support@foo
Cc: support@bar

but not a big deal if we can't stop that.

 

[Stoiko Ivanov]

on a quick test this seems to work fine here:

From: sender <sender@sender.domain.example>
To: receiver@domain.example, support@test1.domain.example
 support@test2.domain.example
Bcc: 
Subject: test 
[code]

gets matched by To=(support@.*){2,}

What would not get matched is 2 'To' headers each with one containing one 'support@' - afaict

 

[Stoiko Ivanov]

Hi, side note: would be great to also stop people from sending:

To: support@foo
Cc: support@bar

That's not really possible with the current rulesystem - it matches certain headers with regex - there is no possiblity to join multiple different headers together and match on those.

 

[Joe Botha]

on a quick test this seems to work fine here

Hi, when testing with Gmail and mutt, it also works for me.

When using Apple mail, which sends To in multiple lines, it does not match. Asked a friend to test from Windows (not sure which mail client) also did not match.

 

[Stoiko Ivanov]

When using Apple mail, which sends To in multiple lines, it does not match. Asked a friend to test from Windows (not sure which mail client) also did not match.

Yes - multiple instances of the header are matched individually:
https://git.proxmox.com/?p=pmg-api....7a6b53a9f294a5a7b206bd2a8fe0a991;hb=HEAD#l108

if you like you can open an enhancement request at https://bugzilla.proxmox.com - no promises when/if we'll implement this though.

 

[Joe Botha]

Hi, is the regex logic in Perl?

Perl seems to support this with /s

Maybe this should be the default behaviour for match-field setting.

ps. the UI can also make it more obvious if AND or OR logic is being used.

 

[Joe Botha]

bug 4498 open

https://bugzilla.proxmox.com/show_bug.cgi?id=4498

 

[Stoiko Ivanov]

Hi, is the regex logic in Perl?

Perl seems to support this with /s

Maybe this should be the default behaviour for match-field setting.

No - not quite - this is how the headers are extracted from the mail - the for loop I linked iterates over all occurrences of a To header individually so the /s switch would not help - and if it's only one header with multiple lines - those are joined together on extraction so /s is not needed.

Thanks for the enhancement request.

 

[Joe Botha]

Hi

The solution using (?s)...

(?s)(support@.*){2,}