decrypt is not de-encrypt and then verify ?

[Matthias Odisio]

Hello,

(Thank you David for your reply to my former message.)

In the manual, decrypt is told to decrypt the message and then to verify 
it if it is signed.

The following make me think it may not be strictly the same :
0. Consider a text file f.txt
1. clearsign it: gpg -o fs.txt --clearsign f.txt
2. modify fs.txt by adding lines in the beginning (some mailers 
-- possibly mis-configurated :) -- do that!)

******************************
some 
garbage lines

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

[...]
-----BEGIN PGP SIGNATURE-----

[...]
-----END PGP SIGNATURE-----
*******************************

3. encrypt fs.txt: gpg -o fse.txt --armor --encrypt fs.txt
4. decrypt fse.txt: gpg -o fsed.txt --decrypt fse.txt 
decrypt don't verify signature
5. verify signature: gpg --verify fsed.txt
gpg was able to perform the verification !

PGP handling by mailers appears to be quite drafty by now, and maybe that 
could explain misfunctionnements when sending message. In the case 
considered above, the mailer seems to add these 3 "garbage" lines :
***
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8bit

***

By the way, I've subscribed to this mailing list now, so you don't need 
any more to cc me on reply.
Matthias