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If I have a GPG file that's passphrase protected, with no key, is it still encrypted? (It was hard to google for an answer to that question). A guy on answers.yahoo.com said it's not. So... what's the point of the passphrase? I don't get it.

From what I've read, GPG permits either a passphrase, or a key file, but the two are mutually exclusive right? You can't have both the key file and a passphrase?

Anyway, I read up on this a lot and I can't get a grasp on that. - If you can tell me that a passphrase alone provides encryption that's fine, thanks.

Cas
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Mike
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1 Answers1

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From the GPG man page under Commands to select the type of operation

   --symmetric

   -c     Encrypt  with a symmetric cipher using a passphrase. The default
          symmetric cipher used is CAST5,  but  may  be  chosen  with  the
          --cipher-algo  option.  This  option may be combined with --sign
          (for a signed and symmetrically  encrypted  message),  --encrypt
          (for  a  message  that  may  be  decrypted via a secret key or a
          passphrase), or --sign and --encrypt together (for a signed mes-
          sage that may be decrypted via a secret key or a passphrase).

Yes, encryption with a passphrase is encryption (although usually theoretically not quite as strong since passphrases normally have less entropy than public keys) and in GPG passphrase encryption can be combined with public-key encryption, as well as publickey signature.

As a general rule, information about a program is very often contained in the documentation for that program; that is in fact the reason documentation is created.

dave_thompson_085
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