1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2010 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  *
  25  * Copyright 2017 Nexenta Systems, Inc.  All rights reserved.
  26  */
  27 
  28 #include <smbsrv/smb_kproto.h>
  29 
  30 /*
  31  * The echo request is used to test the connection to the server,
  32  * and to see if the server is still responding.  The tid is ignored,
  33  * so this request may be sent to the server even if there are no
  34  * tree connections to the server.
  35  *
  36  * Each response echoes the data sent, though ByteCount may indicate
  37  * no data. If echo-count is zero, no response is sent.
  38  */
  39 smb_sdrc_t
  40 smb_pre_echo(smb_request_t *sr)
  41 {
  42         DTRACE_SMB_START(op__Echo, smb_request_t *, sr);
  43         return (SDRC_SUCCESS);
  44 }
  45 
  46 void
  47 smb_post_echo(smb_request_t *sr)
  48 {
  49         DTRACE_SMB_DONE(op__Echo, smb_request_t *, sr);
  50 }
  51 
  52 static unsigned short smb_max_echo = 10;
  53 
  54 smb_sdrc_t
  55 smb_com_echo(struct smb_request *sr)
  56 {
  57         unsigned short necho;
  58         unsigned short nbytes;
  59         unsigned short i;
  60         struct mbuf_chain reply;
  61         char *data;
  62         uint16_t        pid_hi, pid_lo;
  63 
  64         pid_hi = sr->smb_pid >> 16;
  65         pid_lo = (uint16_t)sr->smb_pid;
  66 
  67         if (smbsr_decode_vwv(sr, "w", &necho) != 0)
  68                 return (SDRC_ERROR);
  69 
  70         /*
  71          * Don't let the client fool us into doing
  72          * more work than is "reasonable".
  73          */
  74         if (necho > smb_max_echo)
  75                 necho = smb_max_echo;
  76 
  77         nbytes = sr->smb_bcc;
  78         data = smb_srm_zalloc(sr, nbytes);
  79 
  80         if (smb_mbc_decodef(&sr->smb_data, "#c", nbytes, data))
  81                 return (SDRC_ERROR);
  82 
  83         for (i = 1; i <= necho; ++i) {
  84 
  85                 /*
  86                  * According to [MS-CIFS] 3.3.5.32 echo is
  87                  * subject to cancellation.
  88                  */
  89                 if (sr->sr_state != SMB_REQ_STATE_ACTIVE)
  90                         break;
  91 
  92                 MBC_INIT(&reply, SMB_HEADER_ED_LEN + 10 + nbytes);
  93 
  94                 (void) smb_mbc_encodef(&reply, SMB_HEADER_ED_FMT,
  95                     sr->first_smb_com,
  96                     sr->smb_rcls,
  97                     sr->smb_reh,
  98                     sr->smb_err,
  99                     sr->smb_flg | SMB_FLAGS_REPLY,
 100                     sr->smb_flg2,
 101                     pid_hi,
 102                     sr->smb_sig,
 103                     sr->smb_tid,
 104                     pid_lo,
 105                     sr->smb_uid,
 106                     sr->smb_mid);
 107 
 108                 (void) smb_mbc_encodef(&reply, "bww#c", 1, i,
 109                     nbytes, nbytes, data);
 110 
 111                 if (sr->session->signing.flags & SMB_SIGNING_ENABLED)
 112                         smb_sign_reply(sr, &reply);
 113 
 114                 (void) smb_session_send(sr->session, 0, &reply);
 115 
 116                 delay(MSEC_TO_TICK(100));
 117         }
 118 
 119         return (SDRC_NO_REPLY);
 120 }