rmt/rmt.c

   1 /*
   2  *      Ported to Linux's Second Extended File System as part of the
   3  *      dump and restore backup suit
   4  *      Remy Card <card@Linux.EU.Org>, 1994-1997
   5  *      Stelian Pop <stelian@popies.net>, 1999-2000
   6  *      Stelian Pop <stelian@popies.net> - Alcôve <www.alcove.com>, 2000-2002
   7  */
   8
   9 /*
  10  * Copyright (c) 1983, 1993
  11  *      The Regents of the University of California.  All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. Neither the name of the University nor the names of its contributors
  22  *    may be used to endorse or promote products derived from this software
  23  *    without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35  * SUCH DAMAGE.
  36  */
  37
  38 #ifndef lint
  39 static const char rcsid[] =
  40         "$Id: rmt.c,v 1.24 2003/03/30 15:40:40 stelian Exp $";
  41 #endif /* not linux */
  42
  43 /*
  44  * rmt
  45  */
  46 #include <config.h>
  47 #include <compatlfs.h>
  48 #include <rmtflags.h>
  49 #include <sys/types.h>
  50 #include <sys/socket.h>
  51 #include <sys/mtio.h>
  52 #include <errno.h>
  53 #include <fcntl.h>
  54 #ifndef __linux__
  55 #include <sgtty.h>
  56 #endif
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <unistd.h>
  61
  62 static int      tape = -1;
  63
  64 static char     *record;
  65 static int      maxrecsize = -1;
  66
  67 #define SSIZE   64
  68 static char     device[SSIZE];
  69 static char     count[SSIZE], filemode[SSIZE], pos[SSIZE], op[SSIZE];
  70
  71 static char     resp[BUFSIZ];
  72
  73 static FILE     *debug;
  74 #define DEBUG(f)        if (debug) fprintf(debug, f)
  75 #define DEBUG1(f,a)     if (debug) fprintf(debug, f, a)
  76 #define DEBUG2(f,a1,a2) if (debug) fprintf(debug, f, a1, a2)
  77
  78 /*
  79  * Support for Sun's extended RMT protocol
  80  *      code originally written by Jörg Schilling <schilling@fokus.gmd.de>
  81  *      and relicensed by his permission from GPL to BSD for use in dump.
  82  *
  83  *      rmt_version is 0 for regular clients (Linux included)
  84  *      rmt_version is 1 for extended clients (Sun especially). In this case
  85  *              we support some extended commands (see below) and we remap
  86  *              the ioctl commands to the UNIX "standard", as per:
  87  *                      ftp://ftp.fokus.gmd.de/pub/unix/star/README.mtio
  88  *
  89  *      In order to use rmt version 1, a client must send "I-1\n0\n"
  90  *      before issuing the other I commands.
  91  */
  92 static int      rmt_version = 0;
  93 #define RMTI_VERSION    -1
  94 #define RMT_VERSION     1
  95
  96 /* Extended 'i' commands */
  97 #define RMTI_CACHE      0
  98 #define RMTI_NOCACHE    1
  99 #define RMTI_RETEN      2
 100 #define RMTI_ERASE      3
 101 #define RMTI_EOM        4
 102 #define RMTI_NBSF       5
 103
 104 /* Extended 's' comands */
 105 #define MTS_TYPE        'T'
 106 #define MTS_DSREG       'D'
 107 #define MTS_ERREG       'E'
 108 #define MTS_RESID       'R'
 109 #define MTS_FILENO      'F'
 110 #define MTS_BLKNO       'B'
 111 #define MTS_FLAGS       'f'
 112 #define MTS_BF          'b'
 113
 114 char    *checkbuf __P((char *, int));
 115 void     error __P((int));
 116 void     getstring __P((char *));
 117
 118 int
 119 main(int argc, char *argv[])
 120 {
 121         OFF_T rval = 0;
 122         char c;
 123         int n, i, cc, oflags;
 124         unsigned long block = 0;
 125
 126         argc--, argv++;
 127         if (argc > 0) {
 128                 debug = fopen(*argv, "w");
 129                 if (debug == 0)
 130                         exit(1);
 131                 (void)setbuf(debug, (char *)0);
 132         }
 133 top:
 134         errno = 0;
 135         rval = 0;
 136         if (read(0, &c, 1) != 1)
 137                 exit(0);
 138         switch (c) {
 139
 140         case 'O':
 141                 if (tape >= 0)
 142                         (void) close(tape);
 143                 getstring(device);
 144                 getstring(filemode);
 145                 DEBUG2("rmtd: O %s %s\n", device, filemode);
 146                 /*
 147                  * Translate extended GNU syntax into its numeric platform equivalent
 148                  */
 149                 oflags = rmtflags_toint(filemode);
 150 #ifdef  O_TEXT
 151                 /*
 152                  * Default to O_BINARY the client may not know that we need it.
 153                  */
 154                 if ((oflags & O_TEXT) == 0)
 155                         oflags |= O_BINARY;
 156 #endif
 157                 DEBUG2("rmtd: O %s %d\n", device, oflags);
 158                 /*
 159                  * XXX the rmt protocol does not provide a means to
 160                  * specify the permission bits; allow rw for everyone,
 161                  * as modified by the users umask
 162                  */
 163                 tape = OPEN(device, oflags, 0666);
 164                 if (tape < 0)
 165                         goto ioerror;
 166                 block = 0;
 167                 goto respond;
 168
 169         case 'C':
 170                 DEBUG1("rmtd: C  (%lu blocks)\n", block);
 171                 getstring(device);              /* discard */
 172                 if (close(tape) < 0)
 173                         goto ioerror;
 174                 tape = -1;
 175                 block = 0;
 176                 goto respond;
 177
 178         case 'L':
 179                 getstring(count);
 180                 getstring(pos);
 181                 DEBUG2("rmtd: L %s %s\n", count, pos);
 182                 rval = LSEEK(tape, (OFF_T)atoll(count), atoi(pos));
 183                 if (rval < 0)
 184                         goto ioerror;
 185                 goto respond;
 186
 187         case 'W':
 188                 getstring(count);
 189                 n = atoi(count);
 190                 DEBUG2("rmtd: W %s (block = %lu)\n", count, block);
 191                 record = checkbuf(record, n);
 192                 for (i = 0; i < n; i += cc) {
 193                         cc = read(0, &record[i], n - i);
 194                         if (cc <= 0) {
 195                                 DEBUG("rmtd: premature eof\n");
 196                                 exit(2);
 197                         }
 198                 }
 199                 rval = write(tape, record, n);
 200                 if (rval < 0)
 201                         goto ioerror;
 202                 block += n >> 10;
 203                 goto respond;
 204
 205         case 'R':
 206                 getstring(count);
 207                 DEBUG2("rmtd: R %s (block %lu)\n", count, block);
 208                 n = atoi(count);
 209                 record = checkbuf(record, n);
 210                 rval = read(tape, record, n);
 211                 if (rval < 0)
 212                         goto ioerror;
 213                 (void)sprintf(resp, "A%lld\n", (long long)rval);
 214                 (void)write(1, resp, strlen(resp));
 215                 (void)write(1, record, rval);
 216                 block += n >> 10;
 217                 goto top;
 218
 219         case 'I':
 220                 getstring(op);
 221                 getstring(count);
 222                 DEBUG2("rmtd: I %s %s\n", op, count);
 223                 if (atoi(op) == RMTI_VERSION) {
 224                         rval = RMT_VERSION;
 225                         rmt_version = 1;
 226                 }
 227                 else {
 228                         struct mtop mtop;
 229                         mtop.mt_op = -1;
 230                         if (rmt_version) {
 231                                 /* rmt version 1, assume UNIX client */
 232                                 switch (atoi(op)) {
 233 #ifdef  MTWEOF
 234                                         case 0:
 235                                                 mtop.mt_op = MTWEOF;
 236                                                 break;
 237 #endif
 238 #ifdef  MTFSF
 239                                         case 1:
 240                                                 mtop.mt_op = MTFSF;
 241                                                 break;
 242 #endif
 243 #ifdef  MTBSF
 244                                         case 2:
 245                                                 mtop.mt_op = MTBSF;
 246                                                 break;
 247 #endif
 248 #ifdef  MTFSR
 249                                         case 3:
 250                                                 mtop.mt_op = MTFSR;
 251                                                 break;
 252 #endif
 253 #ifdef  MTBSR
 254                                         case 4:
 255                                                 mtop.mt_op = MTBSR;
 256                                                 break;
 257 #endif
 258 #ifdef  MTREW
 259                                         case 5:
 260                                                 mtop.mt_op = MTREW;
 261                                                 break;
 262 #endif
 263 #ifdef  MTOFFL
 264                                         case 6:
 265                                                 mtop.mt_op = MTOFFL;
 266                                                 break;
 267 #endif
 268 #ifdef  MTNOP
 269                                         case 7:
 270                                                 mtop.mt_op = MTNOP;
 271                                                 break;
 272 #endif
 273                                 }
 274                                 if (mtop.mt_op == -1) {
 275                                         errno = EINVAL;
 276                                         goto ioerror;
 277                                 }
 278                         }
 279                         else {
 280                                 /* rmt version 0, assume linux client */
 281                                 mtop.mt_op = atoi(op);
 282                         }
 283                         mtop.mt_count = atoi(count);
 284                         if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
 285                                 goto ioerror;
 286                         rval = mtop.mt_count;
 287                 }
 288                 goto respond;
 289
 290         case 'i':
 291         {       struct mtop mtop;
 292
 293                 getstring (op);
 294                 getstring (count);
 295                 DEBUG2 ("rmtd: i %s %s\n", op, count);
 296                 switch (atoi(op)) {
 297 #ifdef MTCACHE
 298                         case RMTI_CACHE:
 299                                 mtop.mt_op = MTCACHE;
 300                                 break;
 301 #endif
 302 #ifdef MTNOCACHE
 303                         case RMTI_NOCACHE:
 304                                 mtop.mt_op = MTNOCACHE;
 305                                 break;
 306 #endif
 307 #ifdef MTRETEN
 308                         case RMTI_RETEN:
 309                                 mtop.mt_op = MTRETEN;
 310                                 break;
 311 #endif
 312 #ifdef MTERASE
 313                         case RMTI_ERASE:
 314                                 mtop.mt_op = MTERASE;
 315                                 break;
 316 #endif
 317 #ifdef MTEOM
 318                         case RMTI_EOM:
 319                                 mtop.mt_op = MTEOM;
 320                                 break;
 321 #endif
 322 #ifdef MTNBSF
 323                         case RMTI_NBSF:
 324                                 mtop.mt_op = MTNBSF;
 325                                 break;
 326 #endif
 327                         default:
 328                                 errno = EINVAL;
 329                                 goto ioerror;
 330                 }
 331                 mtop.mt_count = atoi (count);
 332                 if (ioctl (tape, MTIOCTOP, (char *) &mtop) < 0)
 333                         goto ioerror;
 334
 335                 rval = mtop.mt_count;
 336
 337                 goto respond;
 338         }
 339
 340         case 'S':               /* status */
 341                 DEBUG("rmtd: S\n");
 342                 { struct mtget mtget;
 343                   if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
 344                         goto ioerror;
 345                   rval = sizeof (mtget);
 346                   (void)sprintf(resp, "A%lld\n", (long long)rval);
 347                   (void)write(1, resp, strlen(resp));
 348                   (void)write(1, (char *)&mtget, sizeof (mtget));
 349                   goto top;
 350                 }
 351
 352         case 's':
 353         {       char s;
 354                 struct mtget mtget;
 355
 356                 if (read (0, &s, 1) != 1)
 357                         goto top;
 358
 359                 if (ioctl (tape, MTIOCGET, (char *) &mtget) < 0)
 360                         goto ioerror;
 361
 362                 switch (s) {
 363                         case MTS_TYPE:
 364                                 rval = mtget.mt_type;
 365                                 break;
 366                         case MTS_DSREG:
 367                                 rval = mtget.mt_dsreg;
 368                                 break;
 369                         case MTS_ERREG:
 370                                 rval = mtget.mt_erreg;
 371                                 break;
 372                         case MTS_RESID:
 373                                 rval = mtget.mt_resid;
 374                                 break;
 375                         case MTS_FILENO:
 376                                 rval = mtget.mt_fileno;
 377                                 break;
 378                         case MTS_BLKNO:
 379                                 rval = mtget.mt_blkno;
 380                                 break;
 381                         case MTS_FLAGS:
 382                                 rval = mtget.mt_gstat;
 383                                 break;
 384                         case MTS_BF:
 385                                 rval = 0;
 386                                 break;
 387                         default:
 388                                 errno = EINVAL;
 389                                 goto ioerror;
 390                 }
 391
 392                 goto respond;
 393         }
 394
 395         case 'V':               /* version */
 396                 getstring(op);
 397                 DEBUG1("rmtd: V %s\n", op);
 398                 rval = 2;
 399                 goto respond;
 400
 401         default:
 402                 DEBUG1("rmtd: garbage command %c\n", c);
 403                 exit(3);
 404         }
 405 respond:
 406         DEBUG1("rmtd: A %lld\n", (long long)rval);
 407         (void)sprintf(resp, "A%lld\n", (long long)rval);
 408         (void)write(1, resp, strlen(resp));
 409         goto top;
 410 ioerror:
 411         error(errno);
 412         goto top;
 413 }
 414
 415 void getstring(char *bp)
 416 {
 417         int i;
 418         char *cp = bp;
 419
 420         for (i = 0; i < SSIZE; i++) {
 421                 if (read(0, cp+i, 1) != 1)
 422                         exit(0);
 423                 if (cp[i] == '\n')
 424                         break;
 425         }
 426         cp[i] = '\0';
 427 }
 428
 429 char *
 430 checkbuf(char *record, int size)
 431 {
 432
 433         if (size <= maxrecsize)
 434                 return (record);
 435         if (record != 0)
 436                 free(record);
 437         record = malloc(size);
 438         if (record == 0) {
 439                 DEBUG("rmtd: cannot allocate buffer space\n");
 440                 exit(4);
 441         }
 442         maxrecsize = size;
 443         while (size > 1024 &&
 444                setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
 445                 size -= 1024;
 446         return (record);
 447 }
 448
 449 void
 450 error(int num)
 451 {
 452
 453         DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
 454         (void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
 455         (void)write(1, resp, strlen(resp));
 456 }