On 8 Apr 2019, at 17:16, Shawn Heisey via dovecot dovecot@dovecot.org wrote:
On 4/8/2019 4:55 PM, @lbutlr via dovecot wrote:
On 8 Apr 2019, at 16:35, Shawn Heisey via dovecot dovecot@dovecot.org wrote:
I would like to create a sieve rule where I do a regex match on ALL headers, not a specific header. This is a really bad idea. Headers can be quite long, contain data that you do not have control over, and checking all headers will be very expensive and may leave you open to various regex attacks.
I want to catch any email where a specific IP address appears in any header. I do not know what header it might appear in - that could vary widely depending on what email account is being used to send the message.
Really? Where outside the Received headers do IPs appear in your email headers?
But sure, you can come up with a myriad of reasons why you might want to do it. It doesn't make it a good idea.
https://wiki.dovecot.org/Pigeonhole/Sieve
That lists all the supported extensions. I don't see anything that would work for all headers, so I don't think it is possible, but I'll defer to anyone else more knowledgable who comes along.
-- I find your lack of faith disturbing.