dirmngr: Rewrite the LDAP wrapper tool

* dirmngr/ldap-misc.c: New.
* dirmngr/ldap-misc.h: New.
* dirmngr/ks-engine-ldap.c: Include ldap-misc.h.
(ldap_err_to_gpg_err, ldap_to_gpg_err): Move to ldap-misc.c.
* dirmngr/ldap-wrapper.c (ldap_wrapper): Print list of args in debug
mode.
* dirmngr/server.c (lookup_cert_by_pattern): Handle GPG_ERR_NOT_FOUND
the saqme as GPG_ERR_NO_DATA.
* dirmngr/ldap.c (run_ldap_wrapper): Add args tls_mode and ntds.
Remove arg url.  Adjust for changes in dirmngr_ldap.
(url_fetch_ldap): Remove args host and port.  Parse the URL and use
these values to call run_ldap_wrapper.
(attr_fetch_ldap): Pass tls flags to run_ldap_wrapper.
(rfc2254_need_escape, rfc2254_escape): New.
(extfilt_need_escape, extfilt_escape): New.
(parse_one_pattern): Rename to ...
(make_one_filter): this.  Change for new dirmngr_ldap calling
convention.  Make issuer DN searching partly work.
(escape4url, make_url): Remove.
(start_cert_fetch_ldap): Change for new dirmngr_ldap calling
convention.
* dirmngr/dirmngr_ldap.c: Major rewrite.

* dirmngr/t-ldap-misc.c: New.
* dirmngr/t-support.h (DIM, DIMof): New.
* dirmngr/Makefile.am (dirmngr_ldap_SOURCES): Add ldap-misc.c
(module_tests) [USE_LDAP]: Add t-ldap-misc.
(t_ldap_parse_uri_SOURCES): Ditto.
(t_ldap_misc_SOURCES): New.
--

This rewrite allows to properly handle TLS and avoids some code
duplication.

Signed-off-by: Werner Koch <wk@gnupg.org>

dirmngr/ldap-misc.h

@@ -0,0 +1,43 @@
+/* ldap-misc.h - Miscellaneous helpers for LDAP functions
+ * Copyright (C) 2015, 2021 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-or-later
+ */
+
+#ifndef DIRMNGR_LDAP_MISC_H
+#define DIRMNGR_LDAP_MISC_H
+
+#ifdef _WIN32
+# include <winsock2.h>
+# include <winldap.h>
+#else
+# ifdef NEED_LBER_H
+#  include <lber.h>
+# endif
+/* For OpenLDAP, to enable the API that we're using. */
+# define LDAP_DEPRECATED 1
+# include <ldap.h>
+#endif
+
+
+gpg_err_code_t ldap_err_to_gpg_err (int code);
+gpg_err_code_t ldap_to_gpg_err (LDAP *ld);
+gpg_error_t ldap_parse_extfilter (const char *string, int silent,
+                                  char **r_base, int *r_scope, char **r_filter);
+
+
+#endif /*DIRMNGR_LDAP_MISC_H*/