Zitat von Martijn Brinkers <[email protected]>:
today i got a mail fro a well known German Trustcenter with a invalid signature warning (content altered). A former mail to an other account from the same Trustcenter was valid. On inspection it looks like someone altered the encoding because the valid mail has "Content-Transfer-Encoding: 8bit" and the broken one "Content-Transfer-Encoding: quoted-printable". As far as i know a SMTP server should only pass 8bit if the remote site announces 8BITMIME, so i suspect this is the trouble maker because neither Djigzo nor our Virus scan announces 8BITMIME :-( Any comments on this?The application that added the signature is not RFC 3851 compliant. before signing a message the mail agent should convert 8bit mime bodies to 7bit. This is important because if SMTP sees that a server does not support 8bit, it should convert the message to 7bit. Because of this conversion the message has been changed and therefore the signature is no longer valid. So the trouble maker is the application that signed the message :). The problem is that there is not much you can do. In principle you can disable the conversion from 8bit to 7bit in your own gateway (not that I recommend that ;) but you cannot control other intermediate gateways.
Lead me straight to another question: What does Djigzo do if it is feed with 8bit content to sign? Oh, wait... It does not announce 8BITMIME so this should not happen at all, no?
Regards Andreas
smime.p7s
Description: S/MIME Cryptographic Signature
_______________________________________________ Users mailing list [email protected] http://lists.djigzo.com/lists/listinfo/users
