/*

   Unix SMB/CIFS implementation.

   smb2 lib

   Copyright (C) Stefan Metzmacher 2012

   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 "system/network.h"

#include "lib/util/tevent_ntstatus.h"

#include "smb_common.h"

#include "smbXcli_base.h"

struct smb2cli_echo_state {

  uint8_t fixed[0x4];

};

static void smb2cli_echo_done(struct tevent_req *subreq);

struct tevent_req *smb2cli_echo_send(TALLOC_CTX *mem_ctx,

             struct tevent_context *ev,

             struct smbXcli_conn *conn,

             uint32_t timeout_msec)

{

  struct tevent_req *req, *subreq;

  struct smb2cli_echo_state *state;

  uint8_t *fixed;

  req = tevent_req_create(mem_ctx, &state,

        struct smb2cli_echo_state);

  if (req == NULL) {

    return NULL;

  }

  fixed = state->fixed;

  SSVAL(fixed, 0, 4);

  SSVAL(fixed, 2, 0);

  subreq = smb2cli_req_send(state, ev, conn, SMB2_OP_KEEPALIVE,

          0, 0, /* flags */

          timeout_msec,

          NULL, /* tcon */

          NULL, /* session */

          state->fixed, sizeof(state->fixed),

          NULL, 0, /* dyn* */

          0); /* max_dyn_len */

  if (tevent_req_nomem(subreq, req)) {

    return tevent_req_post(req, ev);

  }

  tevent_req_set_callback(subreq, smb2cli_echo_done, req);

  return req;

}

static void smb2cli_echo_done(struct tevent_req *subreq)

{

  struct tevent_req *req =

    tevent_req_callback_data(subreq,

    struct tevent_req);

  NTSTATUS status;

  static const struct smb2cli_req_expected_response expected[] = {

  {

    .status = NT_STATUS_OK,

    .body_size = 0x04

  }

  };

  status = smb2cli_req_recv(subreq, NULL, NULL,

          expected, ARRAY_SIZE(expected));

  TALLOC_FREE(subreq);

  if (tevent_req_nterror(req, status)) {

    return;

  }

  tevent_req_done(req);

}

NTSTATUS smb2cli_echo_recv(struct tevent_req *req)

{

  return tevent_req_simple_recv_ntstatus(req);

}

NTSTATUS smb2cli_echo(struct smbXcli_conn *conn,

          uint32_t timeout_msec)

{

  TALLOC_CTX *frame = talloc_stackframe();

  struct tevent_context *ev;

  struct tevent_req *req;

  NTSTATUS status = NT_STATUS_NO_MEMORY;

  if (smbXcli_conn_has_async_calls(conn)) {

    /*

     * Can't use sync call while an async call is in flight

     */

    status = NT_STATUS_INVALID_PARAMETER;

    goto fail;

  }

  ev = samba_tevent_context_init(frame);

  if (ev == NULL) {

    goto fail;

  }

  req = smb2cli_echo_send(frame, ev, conn, timeout_msec);

  if (req == NULL) {

    goto fail;

  }

  if (!tevent_req_poll_ntstatus(req, ev, &status)) {

    goto fail;

  }

  status = smb2cli_echo_recv(req);

 fail:

  TALLOC_FREE(frame);

  return status;

}