kbx: Add framework for the SEARCH command

* kbx/backend-kbx.c: New.
* kbx/backend-support.c: New.
* kbx/backend.h: New.
* kbx/frontend.c: New.
* kbx/frontend.h: New.
* kbx/kbxserver.c: Implement SEARCH and NEXT command.
* kbx/keybox-search-desc.h (enum pubkey_types): New.
* kbx/keybox-search.c (keybox_get_data): New.
* kbx/keyboxd.c (main): Add a standard resource.

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

1 files changed, 128 insertions, 0 deletions

diff --git a/kbx/backend-support.c b/kbx/backend-support.c
new file mode 100644
index 000000000..28b51875c
--- /dev/null
+++ b/kbx/backend-support.c
@@ -0,0 +1,128 @@
+/* backend-support.c - Supporting functions for the backend.
+ * Copyright (C) 2019 g10 Code GmbH
+ *
+ * This file is part of GnuPG.
+ *
+ * GnuPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses/>.
+ * SPDX-License-Identifier: GPL-3.0+
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+
+#include "keyboxd.h"
+#include "../common/i18n.h"
+#include "../common/asshelp.h"
+#include "backend.h"
+
+
+/* Common definition part of all backend handle.  */
+struct backend_handle_s
+{
+  enum database_types db_type;
+};
+
+
+
+/* Return a string with the name of the database type T.  */
+const char *
+strdbtype (enum database_types t)
+{
+  switch (t)
+    {
+    case DB_TYPE_NONE: return "none";
+    case DB_TYPE_KBX:  return "keybox";
+    }
+  return "?";
+}
+
+
+/* Return a new backend ID.  Backend IDs are used to identify backends
+ * without using the actual object.  The number of backend resources
+ * is limited because they are specified in the config file.  Thus an
+ * overflow check is not required.  */
+unsigned int
+be_new_backend_id (void)
+{
+  static unsigned int last;
+
+  return ++last;
+}
+
+
+/* Release the backend described by HD.  This is a generic function
+ * which dispatches to the the actual backend.  */
+void
+be_generic_release_backend (ctrl_t ctrl, backend_handle_t hd)
+{
+  if (!hd)
+    return;
+  switch (hd->db_type)
+    {
+    case DB_TYPE_NONE:
+      xfree (hd);
+      break;
+    case DB_TYPE_KBX:
+      be_kbx_release_resource (ctrl, hd);
+      break;
+    default:
+      log_error ("%s: faulty backend handle of type %d given\n",
+                 __func__, hd->db_type);
+    }
+}
+
+
+/* Release the request object REQ.  */
+void
+be_release_request (db_request_t req)
+{
+  db_request_part_t part, partn;
+
+  if (!req)
+    return;
+
+  for (part = req->part; part; part = partn)
+    {
+      partn = part->next;
+      be_kbx_release_kbx_hd (part->kbx_hd);
+      xfree (part);
+    }
+}
+
+
+/* Return the public key (BUFFER,BUFLEN) which has the type
+ * PUBVKEY_TYPE to the caller.  Owenership of BUFFER is taken by thgis
+ * function even in the error case.  */
+gpg_error_t
+be_return_pubkey (ctrl_t ctrl, void *buffer, size_t buflen,
+                  enum pubkey_types pubkey_type)
+{
+  gpg_error_t err;
+
+  err = status_printf (ctrl, "PUBKEY_TYPE", "%d", pubkey_type);
+  if (err)
+    goto leave;
+
+  if (ctrl->no_data_return)
+    err = 0;
+  else
+    err = kbxd_write_data_line(ctrl, buffer, buflen);
+
+ leave:
+  xfree (buffer);
+  return err;
+}