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, 3 insertions, 1 deletions

diff --git a/kbx/keybox-file.c b/kbx/keybox-file.c
index f72099348..def896bca 100644
--- a/kbx/keybox-file.c
+++ b/kbx/keybox-file.c
@@ -132,7 +132,7 @@ _keybox_write_blob (KEYBOXBLOB blob, FILE *fp)
 
 /* Write a fresh header type blob. */
 int
-_keybox_write_header_blob (FILE *fp)
+_keybox_write_header_blob (FILE *fp, int for_openpgp)
 {
   unsigned char image[32];
   u32 val;
@@ -143,6 +143,8 @@ _keybox_write_header_blob (FILE *fp)
 
   image[4] = BLOBTYPE_HEADER;
   image[5] = 1; /* Version */
+  if (for_openpgp)
+    image[7] = 0x02; /* OpenPGP data may be available.  */
 
   memcpy (image+8, "KBXf", 4);
   val = time (NULL);