source/libsmb/clireadwrite.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 3.0
   4    client file read/write routines
   5    Copyright (C) Andrew Tridgell 1994-1998
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #define NO_SYSLOG
  23
  24 #include "includes.h"
  25
  26 /****************************************************************************
  27 issue a single SMBread and don't wait for a reply
  28 ****************************************************************************/
  29 static void cli_issue_read(struct cli_state *cli, int fnum, off_t offset,
  30                            size_t size, int i)
  31 {
  32         memset(cli->outbuf,'\0',smb_size);
  33         memset(cli->inbuf,'\0',smb_size);
  34
  35         set_message(cli->outbuf,10,0,True);
  36
  37         CVAL(cli->outbuf,smb_com) = SMBreadX;
  38         SSVAL(cli->outbuf,smb_tid,cli->cnum);
  39         cli_setup_packet(cli);
  40
  41         CVAL(cli->outbuf,smb_vwv0) = 0xFF;
  42         SSVAL(cli->outbuf,smb_vwv2,fnum);
  43         SIVAL(cli->outbuf,smb_vwv3,offset);
  44         SSVAL(cli->outbuf,smb_vwv5,size);
  45         SSVAL(cli->outbuf,smb_vwv6,size);
  46         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
  47
  48         cli_send_smb(cli);
  49 }
  50
  51 /****************************************************************************
  52   read from a file
  53 ****************************************************************************/
  54 size_t cli_read(struct cli_state *cli, int fnum, char *buf, off_t offset, size_t size)
  55 {
  56         char *p;
  57         int total = -1;
  58         int issued=0;
  59         int received=0;
  60 /*
  61  * There is a problem in this code when mpx is more than one.
  62  * for some reason files can get corrupted when being read.
  63  * Until we understand this fully I am serializing reads (one
  64  * read/one reply) for now. JRA.
  65  */
  66 #if 0
  67         int mpx = MAX(cli->max_mux-1, 1);
  68 #else
  69         int mpx = 1;
  70 #endif
  71         int block = (cli->max_xmit - (smb_size+32)) & ~1023;
  72         int mid;
  73         int blocks = (size + (block-1)) / block;
  74
  75         if (size == 0) return 0;
  76
  77         while (received < blocks) {
  78                 int size2;
  79
  80                 while (issued - received < mpx && issued < blocks) {
  81                         int size1 = MIN(block, size-issued*block);
  82                         cli_issue_read(cli, fnum, offset+issued*block, size1, issued);
  83                         issued++;
  84                 }
  85
  86                 if (!cli_receive_smb(cli)) {
  87                         return total;
  88                 }
  89
  90                 received++;
  91                 mid = SVAL(cli->inbuf, smb_mid) - cli->mid;
  92                 size2 = SVAL(cli->inbuf, smb_vwv5);
  93
  94                 if (CVAL(cli->inbuf,smb_rcls) != 0) {
  95                         blocks = MIN(blocks, mid-1);
  96                         continue;
  97                 }
  98
  99                 if (size2 <= 0) {
 100                         blocks = MIN(blocks, mid-1);
 101                         /* this distinguishes EOF from an error */
 102                         total = MAX(total, 0);
 103                         continue;
 104                 }
 105
 106                 if (size2 > block) {
 107                         DEBUG(0,("server returned more than we wanted!\n"));
 108                         return -1;
 109                 }
 110                 if (mid >= issued) {
 111                         DEBUG(0,("invalid mid from server!\n"));
 112                         return -1;
 113                 }
 114                 p = smb_base(cli->inbuf) + SVAL(cli->inbuf,smb_vwv6);
 115
 116                 memcpy(buf+mid*block, p, size2);
 117
 118                 total = MAX(total, mid*block + size2);
 119         }
 120
 121         while (received < issued) {
 122                 cli_receive_smb(cli);
 123                 received++;
 124         }
 125
 126         return total;
 127 }
 128
 129
 130 /****************************************************************************
 131 issue a single SMBwrite and don't wait for a reply
 132 ****************************************************************************/
 133 static void cli_issue_write(struct cli_state *cli, int fnum, off_t offset, uint16 mode, char *buf,
 134                             size_t size, int i)
 135 {
 136         char *p;
 137
 138         memset(cli->outbuf,'\0',smb_size);
 139         memset(cli->inbuf,'\0',smb_size);
 140
 141         set_message(cli->outbuf,12,size,True);
 142
 143         CVAL(cli->outbuf,smb_com) = SMBwriteX;
 144         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 145         cli_setup_packet(cli);
 146
 147         CVAL(cli->outbuf,smb_vwv0) = 0xFF;
 148         SSVAL(cli->outbuf,smb_vwv2,fnum);
 149
 150         SIVAL(cli->outbuf,smb_vwv3,offset);
 151         SIVAL(cli->outbuf,smb_vwv5,IS_BITS_SET_ALL(mode, 0x0008) ? 0xFFFFFFFF : 0);
 152         SSVAL(cli->outbuf,smb_vwv7,mode);
 153
 154         SSVAL(cli->outbuf,smb_vwv8,IS_BITS_SET_ALL(mode, 0x0008) ? size : 0);
 155         SSVAL(cli->outbuf,smb_vwv10,size);
 156         SSVAL(cli->outbuf,smb_vwv11,
 157               smb_buf(cli->outbuf) - smb_base(cli->outbuf));
 158
 159         p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11);
 160         memcpy(p, buf, size);
 161
 162         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 163
 164         show_msg(cli->outbuf);
 165         cli_send_smb(cli);
 166 }
 167
 168 /****************************************************************************
 169   write to a file
 170   write_mode: 0x0001 disallow write cacheing
 171               0x0002 return bytes remaining
 172               0x0004 use raw named pipe protocol
 173               0x0008 start of message mode named pipe protocol
 174 ****************************************************************************/
 175 ssize_t cli_write(struct cli_state *cli,
 176                   int fnum, uint16 write_mode,
 177                   char *buf, off_t offset, size_t size)
 178 {
 179         int bwritten = 0;
 180         int issued = 0;
 181         int received = 0;
 182         int mpx = MAX(cli->max_mux-1, 1);
 183         int block = (cli->max_xmit - (smb_size+32)) & ~1023;
 184         int blocks = (size + (block-1)) / block;
 185
 186         while (received < blocks) {
 187
 188                 while ((issued - received < mpx) && (issued < blocks))
 189                 {
 190                         int bsent = issued * block;
 191                         int size1 = MIN(block, size - bsent);
 192
 193                         cli_issue_write(cli, fnum, offset + bsent,
 194                                         write_mode,
 195                                         buf + bsent,
 196                                         size1, issued);
 197                         issued++;
 198                 }
 199
 200                 if (!cli_receive_smb(cli))
 201                 {
 202                         return bwritten;
 203                 }
 204
 205                 received++;
 206
 207                 if (CVAL(cli->inbuf,smb_rcls) != 0)
 208                 {
 209                         break;
 210                 }
 211
 212                 bwritten += SVAL(cli->inbuf, smb_vwv2);
 213         }
 214
 215         while (received < issued && cli_receive_smb(cli))
 216         {
 217                 received++;
 218         }
 219
 220         return bwritten;
 221 }
 222
 223
 224 /****************************************************************************
 225   write to a file using a SMBwrite and not bypassing 0 byte writes
 226 ****************************************************************************/
 227 ssize_t cli_smbwrite(struct cli_state *cli,
 228                      int fnum, char *buf, off_t offset, size_t size1)
 229 {
 230         char *p;
 231         ssize_t total = 0;
 232
 233         do {
 234                 size_t size = MIN(size1, cli->max_xmit - 48);
 235
 236                 memset(cli->outbuf,'\0',smb_size);
 237                 memset(cli->inbuf,'\0',smb_size);
 238
 239                 set_message(cli->outbuf,5, 3 + size,True);
 240
 241                 CVAL(cli->outbuf,smb_com) = SMBwrite;
 242                 SSVAL(cli->outbuf,smb_tid,cli->cnum);
 243                 cli_setup_packet(cli);
 244
 245                 SSVAL(cli->outbuf,smb_vwv0,fnum);
 246                 SSVAL(cli->outbuf,smb_vwv1,size);
 247                 SIVAL(cli->outbuf,smb_vwv2,offset);
 248                 SSVAL(cli->outbuf,smb_vwv4,0);
 249
 250                 p = smb_buf(cli->outbuf);
 251                 *p++ = 1;
 252                 SSVAL(p, 0, size);
 253                 memcpy(p+2, buf, size);
 254
 255                 cli_send_smb(cli);
 256                 if (!cli_receive_smb(cli)) {
 257                         return -1;
 258                 }
 259
 260                 if (CVAL(cli->inbuf,smb_rcls) != 0) {
 261                         return -1;
 262                 }
 263
 264                 size = SVAL(cli->inbuf,smb_vwv0);
 265                 if (size == 0) break;
 266
 267                 size1 -= size;
 268                 total += size;
 269         } while (size1);
 270
 271         return total;
 272 }
 273