Markus Rebensburg schrieb: > Klemens Puritscher schrieb: > > Phil Brutsche schrieb: > > > >> The error message is being created by the LMTP service - NUL > characters > >> aren't valid in ASCII messages. The email in question is being > generated > >> incorrectly somewhere, somehow. > >> > > > > thanks for your reply. > > I know that in the email must be a NUL character, but I cannot see > this NUL character during a tcpdump. > > > > Do you know, or someone else in this list, who can I safe find this > NUL character? > > > > > Maybe it is a problem of lines ine the email which are longer than the > standard allows. Cyrus has a fixed buffer for each line in the email. If > the line is longer than this buffer lmtp inserts a terminating string > character (NUL) itself. This could be the reason you cannot see the > Character in the tcp stream of your mail. > We have the same problem with the NUL character here produced by replies > to emails with some HTML Attachments which have only one linebreak in > the whole file. thanks for this hint. This possibility should I have already fixed, in my exim-config: [...] acl_check_data: deny message = Line too long regex = ^.{4000,} accept [...] (IMHO is the max. line lenght in emails 4000 characters.) Are there other possibilities for the lmtp error "Message contains NUL characters"? regards, Klemens > Regards, > Markus > >> What you need to do is either have the MTA reject the message during > the > >> DATA portion of the SMTP transaction, or have the MTA remove the NUL > >> characters before it passes the message on to the LMTP service. > >> > > > > Yes, this will be the next step. > > > > > >> Your email headers indicate you are using Postfix as your MTA, and I > am > >> not familiar enough with that to tell you how to do what is necessary. > > >> > > > > Yes, that's right for outgoing emails. > > The MTA for incoming emails (mx host) is exim. > > > > regards, > > Klemens > > > > > > > >> Klemens Puritscher wrote: > >> > >>> Hello, > >>> > >>> I have a problem with one of our customers. > >>> When he forwards an email with the thunderbird email client (windows > >>> version), the lmtp-daemon on my cyrus-imapd (v2.3.13) rejects those > >>> emails with the error "554 5.6.0 Message contains NUL characters". > >>> ...ok, that's clear, there are "NUL" characters in the email. > >>> > >>> But I would show my customer, where the "NUL" character is. > >>> > >>> For tests, I generate a testmail, with "echo -e > >>> "From:<sender@xxxxxxxxxxx>\nTo:<recipient@xxxxxxxxxxx>\nSubject: > >>> test\n\ntest\0000test\n.\n" > mail_with_NUL.txt > >>> > >>> Now I dump the lmtp-session on the cyrus-imapd host with: > >>> tcpdump -vv -XX -s 65535 -n -i eth1 "port lmtp > >>> > >>> and I see the "NUL" character: > >>> ... > >>> 0x0230: 7065 6564 2e61 740d 0a0d 0a74 6573 7400 peed.at.... > > >>> > >> test. > >> > >>> 0x0240: 7465 7374 0d0a 2e0d 0a test..... > >>> ... > >>> 65 = e > >>> 73 = s > >>> 74 = t > >>> 00 = NUL > >>> > >>> ...ok, fine, I can find the "NUL" character. > >>> > >>> But when I dump the lmtp-session with the customer email (which > get's > >>> the error "554 5.6.0 Message contains NUL characters"), I cannot > find > >>> this "NUL" character. > >>> > >>> Can someone tell me, what I did wrong? > >>> > >>> Thanks in advance. > >>> > >>> Klemens > >>> > >>> ---- > >>> Cyrus Home Page: http://cyrusimap.web.cmu.edu/ > >>> Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki > >>> List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html > >>> > >> -- > >> > >> Phil Brutsche > >> phil@xxxxxxxxxxxxxxx > >> > > > > ---- > > Cyrus Home Page: http://cyrusimap.web.cmu.edu/ > > Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki > > List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html > > > > > ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html