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, 19 insertions, 0 deletions

diff --git a/kbx/keybox-dump.c b/kbx/keybox-dump.c
index af9052d69..bfe7b4899 100644
--- a/kbx/keybox-dump.c
+++ b/kbx/keybox-dump.c
@@ -141,6 +141,25 @@ dump_header_blob (const byte *buffer, size_t length, FILE *fp)
       return -1;
     }
   fprintf (fp, "Version: %d\n", buffer[5]);
+
+  n = get16 (buffer + 6);
+  fprintf( fp, "Flags:   %04lX", n);
+  if (n)
+    {
+      int any = 0;
+
+      fputs (" (", fp);
+      if ((n & 2))
+        {
+          if (any)
+            putc (',', fp);
+          fputs ("openpgp", fp);
+          any++;
+        }
+      putc (')', fp);
+    }
+  putc ('\n', fp);
+
   if ( memcmp (buffer+8, "KBXf", 4))
     fprintf (fp, "[Error: invalid magic number]\n");