gpg: Take care to use pubring.kbx if it has ever been used.

* kbx/keybox-defs.h (struct keybox_handle): Add field for_openpgp.
* kbx/keybox-file.c (_keybox_write_header_blob): Set openpgp header
flag.
* kbx/keybox-blob.c (_keybox_update_header_blob): Add arg for_openpgp
and set header flag.
* kbx/keybox-init.c (keybox_new): Rename to do_keybox_new, make static
and add arg for_openpgp.
(keybox_new_openpgp, keybox_new_x509): New.  Use them instead of the
former keybox_new.
* kbx/keybox-update.c (blob_filecopy): Add arg for_openpgp and set the
openpgp header flags.

* g10/keydb.c (rt_from_file): New.  Factored out and extended from
keydb_add_resource.
(keydb_add_resource): Switch to the kbx file if it has the openpgp
flag set.

* kbx/keybox-dump.c (dump_header_blob): Print header flags.
--

The problem was reported by dkg on gnupg-devel (2014-10-07):

  I just discovered a new problem, though, which will affect people on
  systems that have gpg and gpg2 coinstalled:

   0) create a new keyring with gpg2, and use it exclusively with gpg2
  for a while.
   1) somehow (accidentally?) use gpg (1.4.x) again -- this creates
  ~/.gnupg/pubring.gpg
   2) future runs of gpg2 now only look at pubring.gpg and ignore
  pubring.kbx -- the keys you had accumulated in the keybox are no
  longer listed in the output of gpg2 --list-keys

Note that gpgsm has always used pubring.kbx and thus this file might
already be there but without gpg ever inserted a key.  The new flag in
the KBX header gives us an indication whether a KBX file has ever been
written by gpg >= 2.1.  If that is the case we will use it instead of
the default pubring.gpg.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 2 insertions, 1 deletions

diff --git a/kbx/keybox-defs.h b/kbx/keybox-defs.h
index 7bbcf83cf..415a3efff 100644
--- a/kbx/keybox-defs.h
+++ b/kbx/keybox-defs.h
@@ -101,6 +101,7 @@ struct keybox_handle {
   int eof;
   int error;
   int ephemeral;
+  int for_openpgp;        /* Used by gpg.  */
   struct keybox_found_s found;
   struct keybox_found_s saved_found;
   struct {
@@ -176,7 +177,7 @@ int  _keybox_new_blob (KEYBOXBLOB *r_blob,
 void _keybox_release_blob (KEYBOXBLOB blob);
 const unsigned char *_keybox_get_blob_image (KEYBOXBLOB blob, size_t *n);
 off_t _keybox_get_blob_fileoffset (KEYBOXBLOB blob);
-void _keybox_update_header_blob (KEYBOXBLOB blob);
+void _keybox_update_header_blob (KEYBOXBLOB blob, int for_openpgp);
 
 /*-- keybox-openpgp.c --*/
 gpg_error_t _keybox_parse_openpgp (const unsigned char *image, size_t imagelen,