On 03/25/2016 02:36 PM, [email protected] wrote:
> 
> Zitat von Matthias Henze <[email protected]>:
> 
>> Hi,
>>
>> I had several discussions with other vendors of mail encryption
>> gateways and all told me that I'm wrong. But today Ciphermail did some
>> thing I've predicted and proved that I was right.
>>
>> This is what I think, please correct me if I'm wrong:
>>
>> For me s/Mime (like PGP) is a encryption system based on public and
>> private keys. If some one has access to the public key he can encrypt
>> some thing which only can be decrypted with the private key. So, when
>> some one sends an s/Mime signed mail to me I should be able to send a
>> encrypted mail to him even if I do not have a s/Mime certificate for
>> my e-mail address on my system.
>>
>> Exactly this happened on my site with Ciphermail. I have a s/Mime
>> certificate for my e-mail addresses imported in Ciphermail and some
>> one else sent a signed mail to me. With this mail Ciphermail stored
>> the public key of the third party. When I mail to him Ciphermail does
>> what I would expect and encrypts the mails. Yesterday a other mail
>> user of my site which has no certificate in Ciphermail received a mail
>> from exact the same person and replied. The reply got encrypted by
>> Chiphermail despite the sender has no certificate imported to
>> Chiphermail. This was what I would expect to happen.
>>
>> Bravo Ciphermail! :-) And thank you Ciphermail! You proved me right!
>>
>> I had a discussion with the support of an other encryption gateway and
>> asked them, why mail sent to me from the other site got not encrypted
>> despite the system recorded my signature with my public key. They told
>> me that the mail do not get encrypted because the *sender* does not
>> have a certificate imported to their system and that it is impossible
>> to send s/Mime encrypted mails without a certificate for the *sender*.
> 
> This is a common (mis)behavior of e-mail clients, they refuse to sent
> encrypted e-mail if they are not able to store the e-mail encrypted in
> the "sent" folder. This is only possible if the *sender* also has a
> certificate and a private key, but this not mandated by S/MIME standard.
> I guess the other party simply adapted this behavior without rethinking
> if it is useful for a gateway at all.

Oh I now see I completely  misunderstood the original question :) As
Andreas already explained, email clients want to store the message
encrypted in the sent items folder and therefore requires that the
sender has a key. With a gateway this is not required.

Kind regards,

Martijn Brinkers


-- 
CipherMail email encryption

Email encryption with support for S/MIME, OpenPGP, PDF encryption and
secure webmail pull.

https://www.ciphermail.com

Twitter: http://twitter.com/CipherMail
_______________________________________________
Users mailing list
[email protected]
https://lists.djigzo.com/lists/listinfo/users

Reply via email to