What causes this?

Gateway
1

What causes this? See the attached EML file. The mail is duplicated (with duplicate MIME headers) into a attached file, when Djigzo validates the mail. What can cause such a “mishap”?

This does only happen with lists.djigzo.com

Re_DjigzousersSecurityoftheX-Djigzo-Info-headers.eml|attachment (4 Bytes)

2

The reason for this is a bit technical. The message sent by Andreas was
S/MIME digitally signed. Since the mailing list server (mailman) needs
to add a banner to the message, it needs to modify the message. The
authors of mailman decided to create a new multipart/mixed part, add the
signed message as a sub-part and then added the banner. The problem now
is that the resulting message is no longer a valid S/MIME message. The
CipherMail gateway however can detect this situation and "repair" the
message to be a valid S/MIME message. It does this by detecting that a
part is S/MIME. This part is then converted into an attached message
(hence the attached message.eml name). This attached message is a valid
S/MIME message which can be validated with your email client. The main
reason for adding this is that there are a lot of "add banner to
outgoing email" services which mess-up S/MIME email because those
services do not understand S/MIME.

Kind regards,

Martijn Brinkers

···

On 03/09/2015 02:40 PM, Sebastian Nielsen wrote:

What causes this? See the attached EML file. The mail is duplicated
(with duplicate MIME headers) into a attached file, when Djigzo
validates the mail. What can cause such a “mishap”?

This does only happen with lists.djigzo.com

--
CipherMail email encryption

Open source email encryption gateway with support for S/MIME, OpenPGP
and PDF messaging.

Twitter: http://twitter.com/CipherMail

3

Zitat von Martijn Brinkers <martijn(a)djigzo.com>:

···

On 03/09/2015 02:40 PM, Sebastian Nielsen wrote:

What causes this? See the attached EML file. The mail is duplicated
(with duplicate MIME headers) into a attached file, when Djigzo
validates the mail. What can cause such a “mishap”?

This does only happen with lists.djigzo.com

The reason for this is a bit technical. The message sent by Andreas was
S/MIME digitally signed. Since the mailing list server (mailman) needs
to add a banner to the message, it needs to modify the message. The
authors of mailman decided to create a new multipart/mixed part, add the
signed message as a sub-part and then added the banner. The problem now
is that the resulting message is no longer a valid S/MIME message. The
CipherMail gateway however can detect this situation and "repair" the
message to be a valid S/MIME message. It does this by detecting that a
part is S/MIME. This part is then converted into an attached message
(hence the attached message.eml name). This attached message is a valid
S/MIME message which can be validated with your email client. The main
reason for adding this is that there are a lot of "add banner to
outgoing email" services which mess-up S/MIME email because those
services do not understand S/MIME.

Kind regards,

Martijn Brinkers

Uh, sorry.

I forgot to exclude this list from S/MIME...

Should be ok now

Regards

Andreas