/*
   Unix SMB/CIFS implementation.
   async implementation of WINBINDD_PING_DC
   Copyright (C) Volker Lendecke 2009

   This program 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.

   This program 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 <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "winbindd.h"
#include "librpc/gen_ndr/ndr_winbind_c.h"

struct winbindd_ping_dc_state {
	const char *dcname;
	NTSTATUS result;
};

static void winbindd_ping_dc_done(struct tevent_req *subreq);

struct tevent_req *winbindd_ping_dc_send(TALLOC_CTX *mem_ctx,
					 struct tevent_context *ev,
					 struct winbindd_cli_state *cli,
					 struct winbindd_request *request)
{
	struct tevent_req *req, *subreq;
	struct winbindd_ping_dc_state *state;
	struct winbindd_domain *domain;

	req = tevent_req_create(mem_ctx, &state,
				struct winbindd_ping_dc_state);
	if (req == NULL) {
		return NULL;
	}

	if (request->domain_name[0] == '\0') {
		/* preserve old behavior, when no domain name is given */
		domain = find_our_domain();
	} else {
		domain = find_trust_from_name_noinit(request->domain_name);
	}
	if (domain == NULL) {
		tevent_req_nterror(req, NT_STATUS_NO_SUCH_DOMAIN);
		return tevent_req_post(req, ev);
	}
	if (domain->internal) {
		const char *d = lp_dnsdomain();
		const char *n = lp_netbios_name();

		/*
		 * Internal domains are passdb based, we can always
		 * contact them.
		 */

		if (d != NULL) {
			char *h;
			h = strlower_talloc(mem_ctx, n);
			if (tevent_req_nomem(h, req)) {
				return tevent_req_post(req, ev);
			}

			state->dcname = talloc_asprintf(state, "%s.%s", h, d);
			TALLOC_FREE(h);

			if (tevent_req_nomem(state->dcname, req)) {
				return tevent_req_post(req, ev);
			}
		} else {
			state->dcname = talloc_strdup(state, n);
			if (tevent_req_nomem(state->dcname, req)) {
				return tevent_req_post(req, ev);
			}
		}

		tevent_req_done(req);
		return tevent_req_post(req, ev);
	}

	subreq = dcerpc_wbint_PingDc_send(state, ev, dom_child_handle(domain),
					  &state->dcname);
	if (tevent_req_nomem(subreq, req)) {
		return tevent_req_post(req, ev);
	}
	tevent_req_set_callback(subreq, winbindd_ping_dc_done, req);
	return req;
}

static void winbindd_ping_dc_done(struct tevent_req *subreq)
{
	struct tevent_req *req = tevent_req_callback_data(
		subreq, struct tevent_req);
	struct winbindd_ping_dc_state *state = tevent_req_data(
		req, struct winbindd_ping_dc_state);
	NTSTATUS status, result;

	status = dcerpc_wbint_PingDc_recv(subreq, state, &result);
	state->result = result;
	if (any_nt_status_not_ok(status, result, &status)) {
		tevent_req_nterror(req, status);
		return;
	}
	tevent_req_done(req);
}

NTSTATUS winbindd_ping_dc_recv(struct tevent_req *req,
			       struct winbindd_response *presp)
{
	struct winbindd_ping_dc_state *state = tevent_req_data(
		req, struct winbindd_ping_dc_state);
	NTSTATUS status;

	if (tevent_req_is_nterror(req, &status)) {
		return status;
	}

	if (!NT_STATUS_IS_OK(state->result)) {
		set_auth_errors(presp, state->result);
	}

	if (state->dcname) {
		presp->extra_data.data = talloc_strdup(presp, state->dcname);
		if (presp->extra_data.data == NULL) {
			return NT_STATUS_NO_MEMORY;
		}
		presp->length += strlen((char *)presp->extra_data.data) + 1;
	}

	tevent_req_received(req);
	return NT_STATUS_OK;
}