Fossa Guard V0.3.1 Interoperability Mission

New V0.3.1 (aka beta 3) of free S/MIME solution for Gmail has been released with Interoperability mission on board. Below supported and tested scenarios:

Microsoft Outlook specifics 

One interesting issue was discovered during integration with MS Outlook. As you may know, S/MIME depends on PKCS#7 format to transfer messages. In its turn, PKCS#7 relies on ASN.1 DER/BER encoding. DER/BER encoding is standard TLV (Type / Length / Value) and Length can be encoded in 2 forms: a definite length form and an indefinite length form (refer to X.690 8.1.3). 

Every e-mail client we tested Fossa Guard with supports both Length forms, however, MS Outlook supports only indefinite length form.

Sent TO Gmail + FossaGuard from

	Mozilla Thunderbird	Outlook (desktop)	iOS Mail	Android + CipherMail
multipart/signed	OK	OK	OK	OK
signed-data		OK
enveloped-data	OK	OK	OK	OK
enveloped-data (multipart/signed)	OK	OK	OK	OK
enveloped-data (signed-data)		OK

Sent FROM Gmail + FossaGuard to

	Mozilla Thunderbird	Outlook (desktop)	iOS Mail	Android + CipherMail
signed-data	OK	OK	OK	OK
enveloped-data	OK	OK	OK	OK
enveloped-data (signed-data)	OK	OK	OK	OK

Documentation and video updates are coming soon ...

With love from Fossa Team 

on Groundhog day, 2017