source3/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 /*
  59  * There is a problem in this code when mpx is more than one.
  60  * for some reason files can get corrupted when being read.
  61  * Until we understand this fully I am serializing reads (one
  62  * read/one reply) for now. JRA.
  63  */
  64 #if 0
  65         int mpx = MAX(cli->max_mux-1, 1);
  66 #else
  67         int mpx = 1;
  68 #endif
  69         int block;
  70         int mid;
  71         int blocks;
  72         /* issued is the number of readX requests we have sent so far */
  73         int issued=0;
  74         /* received is the number of readX replies we have received */
  75         int received=0;
  76
  77         /* maybe its a very silly request? */
  78         if (size == 0) return 0;
  79
  80         /* set block to the maximum size we can handle in one readX,
  81            rounded down to a multiple of 1024 */
  82         block = (cli->max_xmit - (smb_size+32)) & ~1023;
  83
  84         /* work out how many readX calls we will need in total */
  85         blocks = (size + (block-1)) / block;
  86
  87         while (received < blocks) {
  88                 int size2;
  89
  90                 while (issued - received < mpx && issued < blocks) {
  91                         int size1 = MIN(block, size-issued*block);
  92                         cli_issue_read(cli, fnum, offset+issued*block, size1, issued);
  93                         issued++;
  94                 }
  95
  96                 if (!cli_receive_smb(cli)) {
  97                         return total;
  98                 }
  99
 100                 received++;
 101                 mid = SVAL(cli->inbuf, smb_mid) - cli->mid;
 102                 size2 = SVAL(cli->inbuf, smb_vwv5);
 103
 104                 if (CVAL(cli->inbuf,smb_rcls) != 0) {
 105                         blocks = MIN(blocks, mid-1);
 106                         continue;
 107                 }
 108
 109                 if (size2 <= 0) {
 110                         blocks = MIN(blocks, mid-1);
 111                         /* this distinguishes EOF from an error */
 112                         total = MAX(total, 0);
 113                         continue;
 114                 }
 115
 116                 if (size2 > block) {
 117                         DEBUG(0,("server returned more than we wanted!\n"));
 118                         return -1;
 119                 }
 120                 if (mid >= issued) {
 121                         DEBUG(0,("invalid mid from server!\n"));
 122                         return -1;
 123                 }
 124                 p = smb_base(cli->inbuf) + SVAL(cli->inbuf,smb_vwv6);
 125
 126                 memcpy(buf+mid*block, p, size2);
 127
 128                 total = MAX(total, mid*block + size2);
 129         }
 130
 131         while (received < issued) {
 132                 cli_receive_smb(cli);
 133                 received++;
 134         }
 135
 136         return total;
 137 }
 138
 139
 140 /****************************************************************************
 141 issue a single SMBwrite and don't wait for a reply
 142 ****************************************************************************/
 143 static void cli_issue_write(struct cli_state *cli, int fnum, off_t offset, uint16 mode, char *buf,
 144                             size_t size, int i)
 145 {
 146         char *p;
 147
 148         memset(cli->outbuf,'\0',smb_size);
 149         memset(cli->inbuf,'\0',smb_size);
 150
 151         if (size > 0xFFFF)
 152                 set_message(cli->outbuf,14,0,True);
 153         else
 154                 set_message(cli->outbuf,12,0,True);
 155
 156         CVAL(cli->outbuf,smb_com) = SMBwriteX;
 157         SSVAL(cli->outbuf,smb_tid,cli->cnum);
 158         cli_setup_packet(cli);
 159
 160         CVAL(cli->outbuf,smb_vwv0) = 0xFF;
 161         SSVAL(cli->outbuf,smb_vwv2,fnum);
 162
 163         SIVAL(cli->outbuf,smb_vwv3,offset);
 164         SIVAL(cli->outbuf,smb_vwv5,(mode & 0x0008) ? 0xFFFFFFFF : 0);
 165         SSVAL(cli->outbuf,smb_vwv7,mode);
 166
 167         SSVAL(cli->outbuf,smb_vwv8,(mode & 0x0008) ? size : 0);
 168         SSVAL(cli->outbuf,smb_vwv9,((size>>16)&1));
 169         SSVAL(cli->outbuf,smb_vwv10,size);
 170         SSVAL(cli->outbuf,smb_vwv11,
 171               smb_buf(cli->outbuf) - smb_base(cli->outbuf));
 172
 173         p = smb_base(cli->outbuf) + SVAL(cli->outbuf,smb_vwv11);
 174         memcpy(p, buf, size);
 175         cli_setup_bcc(cli, p+size);
 176
 177         SSVAL(cli->outbuf,smb_mid,cli->mid + i);
 178
 179         show_msg(cli->outbuf);
 180         cli_send_smb(cli);
 181 }
 182
 183 /****************************************************************************
 184   write to a file
 185   write_mode: 0x0001 disallow write cacheing
 186               0x0002 return bytes remaining
 187               0x0004 use raw named pipe protocol
 188               0x0008 start of message mode named pipe protocol
 189 ****************************************************************************/
 190 ssize_t cli_write(struct cli_state *cli,
 191                   int fnum, uint16 write_mode,
 192                   char *buf, off_t offset, size_t size)
 193 {
 194         int bwritten = 0;
 195         int issued = 0;
 196         int received = 0;
 197         int mpx = MAX(cli->max_mux-1, 1);
 198         int block = (cli->max_xmit - (smb_size+32)) & ~1023;
 199         int blocks = (size + (block-1)) / block;
 200
 201         while (received < blocks) {
 202
 203                 while ((issued - received < mpx) && (issued < blocks))
 204                 {
 205                         int bsent = issued * block;
 206                         int size1 = MIN(block, size - bsent);
 207
 208                         cli_issue_write(cli, fnum, offset + bsent,
 209                                         write_mode,
 210                                         buf + bsent,
 211                                         size1, issued);
 212                         issued++;
 213                 }
 214
 215                 if (!cli_receive_smb(cli))
 216                 {
 217                         return bwritten;
 218                 }
 219
 220                 received++;
 221
 222                 if (CVAL(cli->inbuf,smb_rcls) != 0)
 223                 {
 224                         break;
 225                 }
 226
 227                 bwritten += SVAL(cli->inbuf, smb_vwv2);
 228         }
 229
 230         while (received < issued && cli_receive_smb(cli))
 231         {
 232                 received++;
 233         }
 234
 235         return bwritten;
 236 }
 237
 238
 239 /****************************************************************************
 240   write to a file using a SMBwrite and not bypassing 0 byte writes
 241 ****************************************************************************/
 242 ssize_t cli_smbwrite(struct cli_state *cli,
 243                      int fnum, char *buf, off_t offset, size_t size1)
 244 {
 245         char *p;
 246         ssize_t total = 0;
 247
 248         do {
 249                 size_t size = MIN(size1, cli->max_xmit - 48);
 250
 251                 memset(cli->outbuf,'\0',smb_size);
 252                 memset(cli->inbuf,'\0',smb_size);
 253
 254                 set_message(cli->outbuf,5, 0,True);
 255
 256                 CVAL(cli->outbuf,smb_com) = SMBwrite;
 257                 SSVAL(cli->outbuf,smb_tid,cli->cnum);
 258                 cli_setup_packet(cli);
 259
 260                 SSVAL(cli->outbuf,smb_vwv0,fnum);
 261                 SSVAL(cli->outbuf,smb_vwv1,size);
 262                 SIVAL(cli->outbuf,smb_vwv2,offset);
 263                 SSVAL(cli->outbuf,smb_vwv4,0);
 264
 265                 p = smb_buf(cli->outbuf);
 266                 *p++ = 1;
 267                 SSVAL(p, 0, size); p += 2;
 268                 memcpy(p, buf, size); p += size;
 269
 270                 cli_setup_bcc(cli, p);
 271
 272                 cli_send_smb(cli);
 273                 if (!cli_receive_smb(cli)) {
 274                         return -1;
 275                 }
 276
 277                 if (CVAL(cli->inbuf,smb_rcls) != 0) {
 278                         return -1;
 279                 }
 280
 281                 size = SVAL(cli->inbuf,smb_vwv0);
 282                 if (size == 0) break;
 283
 284                 size1 -= size;
 285                 total += size;
 286         } while (size1);
 287
 288         return total;
 289 }
 290