libcli/smb/smb2cli_echo.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    smb2 lib
   4    Copyright (C) Stefan Metzmacher 2012
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "includes.h"
  21 #include "system/network.h"
  22 #include "lib/util/tevent_ntstatus.h"
  23 #include "smb_common.h"
  24 #include "smbXcli_base.h"
  25
  26 struct smb2cli_echo_state {
  27         uint8_t fixed[0x4];
  28 };
  29
  30 static void smb2cli_echo_done(struct tevent_req *subreq);
  31
  32 struct tevent_req *smb2cli_echo_send(TALLOC_CTX *mem_ctx,
  33                                      struct tevent_context *ev,
  34                                      struct smbXcli_conn *conn,
  35                                      uint32_t timeout_msec)
  36 {
  37         struct tevent_req *req, *subreq;
  38         struct smb2cli_echo_state *state;
  39         uint8_t *fixed;
  40
  41         req = tevent_req_create(mem_ctx, &state,
  42                                 struct smb2cli_echo_state);
  43         if (req == NULL) {
  44                 return NULL;
  45         }
  46         fixed = state->fixed;
  47         SSVAL(fixed, 0, 4);
  48         SSVAL(fixed, 2, 0);
  49
  50         subreq = smb2cli_req_send(state, ev, conn, SMB2_OP_KEEPALIVE,
  51                                   0, 0, /* flags */
  52                                   timeout_msec,
  53                                   NULL, /* tcon */
  54                                   NULL, /* session */
  55                                   state->fixed, sizeof(state->fixed),
  56                                   NULL, 0, /* dyn* */
  57                                   0); /* max_dyn_len */
  58         if (tevent_req_nomem(subreq, req)) {
  59                 return tevent_req_post(req, ev);
  60         }
  61         tevent_req_set_callback(subreq, smb2cli_echo_done, req);
  62         return req;
  63 }
  64
  65 static void smb2cli_echo_done(struct tevent_req *subreq)
  66 {
  67         struct tevent_req *req =
  68                 tevent_req_callback_data(subreq,
  69                 struct tevent_req);
  70         NTSTATUS status;
  71         static const struct smb2cli_req_expected_response expected[] = {
  72         {
  73                 .status = NT_STATUS_OK,
  74                 .body_size = 0x04
  75         }
  76         };
  77
  78         status = smb2cli_req_recv(subreq, NULL, NULL,
  79                                   expected, ARRAY_SIZE(expected));
  80         TALLOC_FREE(subreq);
  81         if (tevent_req_nterror(req, status)) {
  82                 return;
  83         }
  84         tevent_req_done(req);
  85 }
  86
  87 NTSTATUS smb2cli_echo_recv(struct tevent_req *req)
  88 {
  89         return tevent_req_simple_recv_ntstatus(req);
  90 }
  91
  92 NTSTATUS smb2cli_echo(struct smbXcli_conn *conn,
  93                       uint32_t timeout_msec)
  94 {
  95         TALLOC_CTX *frame = talloc_stackframe();
  96         struct tevent_context *ev;
  97         struct tevent_req *req;
  98         NTSTATUS status = NT_STATUS_NO_MEMORY;
  99
 100         if (smbXcli_conn_has_async_calls(conn)) {
 101                 /*
 102                  * Can't use sync call while an async call is in flight
 103                  */
 104                 status = NT_STATUS_INVALID_PARAMETER;
 105                 goto fail;
 106         }
 107         ev = samba_tevent_context_init(frame);
 108         if (ev == NULL) {
 109                 goto fail;
 110         }
 111         req = smb2cli_echo_send(frame, ev, conn, timeout_msec);
 112         if (req == NULL) {
 113                 goto fail;
 114         }
 115         if (!tevent_req_poll_ntstatus(req, ev, &status)) {
 116                 goto fail;
 117         }
 118         status = smb2cli_echo_recv(req);
 119  fail:
 120         TALLOC_FREE(frame);
 121         return status;
 122 }