[Gnu-arch-users] crypto signing take 2

[Tom Lord]

First) I get the message that tla should _not_ read passphrases.

Second) Here is an alternative approach:

1) As before, the existence of =meta-info/signed-archive
   indicates that files are supposed to be signed.


2) A user can have files:

     ~/.arch-params/=gpg/=default
     ~/.arch-params/=gpg/<archive-name>

   containing the commands to use to sign by default or for
   a particular archive.   The contents of those files would be
   something like:

        agpg --detatch-sign --local-user FOO %F

   where tla replaces %F by a file name.

   (The default default command should presumably be

        gpg --detatch-sign %F
   )


3) (internals) the arch_pfs_put_file routine will sign files
   a new arch_pfs_put_atomic routine will be added

   If a regular file is being written to a signed archive,
   it gets signed.

   In two cases, arch_pfs_put_file is currently used in 
   combination with arch_pfs_rename as

        put_file to temp name
        rename from temp name to real name

   A convenience function, arch_pfs_put_atomic will be
   created that performs those two steps, but knows to 
   rename the .sig file too.

   (Also, as before, native fs support should be modified
   to go through the pfs abstraction.)


and that's it.

Two big things are different in this proposal:

  1) no special handling of push-mirror
  2) no reading of the passphrase by tla


One upshot of this is that if you _don't_ use apgp or some other
agent, you'll get prompted for your passphrase a lot.  Oh well.

Another upshot of this is that it lacks a facility for copying
signatures during a push-mirror operation.  I'm not sure that that's
really a problem, though -- an rsync hack can be used to update
mirrors where signature copying is desirable.

-t