sys/lib/libsa/cd9660.c

   1 /*      $NetBSD: cd9660.c,v 1.29 2012/07/23 00:49:20 mhitch Exp $       */
   2
   3 /*
   4  * Copyright (C) 1996 Wolfgang Solfrank.
   5  * Copyright (C) 1996 TooLs GmbH.
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by TooLs GmbH.
  19  * 4. The name of TooLs GmbH may not be used to endorse or promote products
  20  *    derived from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
  23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  25  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  27  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  28  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  29  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  30  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  31  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Stand-alone ISO9660 file reading package.
  36  *
  37  * Note: This doesn't support Rock Ridge extensions, extended attributes,
  38  * blocksizes other than 2048 bytes, multi-extent files, etc.
  39  */
  40 #include <sys/param.h>
  41 #ifdef _STANDALONE
  42 #include <lib/libkern/libkern.h>
  43 #else
  44 #include <string.h>
  45 #endif
  46 #include <fs/cd9660/iso.h>
  47
  48 #include "stand.h"
  49 #include "cd9660.h"
  50
  51 /*
  52  * XXX Does not currently implement:
  53  * XXX
  54  * XXX LIBSA_NO_FS_SYMLINK (does this even make sense?)
  55  * XXX LIBSA_FS_SINGLECOMPONENT
  56  */
  57
  58 struct file {
  59         off_t off;                      /* Current offset within file */
  60         daddr_t bno;                    /* Starting block number  */
  61         off_t size;                     /* Size of file */
  62 };
  63
  64 struct ptable_ent {
  65         char namlen     [ISODCL( 1, 1)];        /* 711 */
  66         char extlen     [ISODCL( 2, 2)];        /* 711 */
  67         char block      [ISODCL( 3, 6)];        /* 732 */
  68         char parent     [ISODCL( 7, 8)];        /* 722 */
  69         char name       [1];
  70 };
  71 #define PTFIXSZ         8
  72 #define PTSIZE(pp)      roundup(PTFIXSZ + isonum_711((pp)->namlen), 2)
  73
  74 #define cdb2devb(bno)   ((bno) * ISO_DEFAULT_BLOCK_SIZE / DEV_BSIZE)
  75
  76 static int      pnmatch(const char *, struct ptable_ent *);
  77 static int      dirmatch(const char *, struct iso_directory_record *);
  78
  79 static int
  80 pnmatch(const char *path, struct ptable_ent *pp)
  81 {
  82         char *cp;
  83         int i;
  84
  85         cp = pp->name;
  86         for (i = isonum_711(pp->namlen); --i >= 0; path++, cp++) {
  87                 if (toupper(*path) == *cp)
  88                         continue;
  89                 return 0;
  90         }
  91         if (*path != '/')
  92                 return 0;
  93         return 1;
  94 }
  95
  96 static int
  97 dirmatch(const char *path, struct iso_directory_record *dp)
  98 {
  99         char *cp;
 100         int i;
 101
 102         /* This needs to be a regular file */
 103         if (dp->flags[0] & 6)
 104                 return 0;
 105
 106         cp = dp->name;
 107         for (i = isonum_711(dp->name_len); --i >= 0; path++, cp++) {
 108                 if (!*path)
 109                         break;
 110                 if (toupper(*path) == *cp)
 111                         continue;
 112                 return 0;
 113         }
 114         if (*path)
 115                 return 0;
 116         /*
 117          * Allow stripping of trailing dots and the version number.
 118          * Note that this will find the first instead of the last version
 119          * of a file.
 120          */
 121         if (i >= 0 && (*cp == ';' || *cp == '.')) {
 122                 /* This is to prevent matching of numeric extensions */
 123                 if (*cp == '.' && cp[1] != ';')
 124                         return 0;
 125                 while (--i >= 0)
 126                         if (*++cp != ';' && (*cp < '0' || *cp > '9'))
 127                                 return 0;
 128         }
 129         return 1;
 130 }
 131
 132 __compactcall int
 133 cd9660_open(const char *path, struct open_file *f)
 134 {
 135         struct file *fp = 0;
 136         void *buf;
 137         struct iso_primary_descriptor *vd;
 138         size_t buf_size, nread, psize, dsize;
 139         daddr_t bno;
 140         int parent, ent;
 141         struct ptable_ent *pp;
 142         struct iso_directory_record *dp = 0;
 143         int rc;
 144
 145         /* First find the volume descriptor */
 146         buf_size = ISO_DEFAULT_BLOCK_SIZE;
 147         buf = alloc(buf_size);
 148         vd = buf;
 149         for (bno = 16;; bno++) {
 150 #if !defined(LIBSA_NO_TWIDDLE)
 151                 twiddle();
 152 #endif
 153                 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
 154                                            ISO_DEFAULT_BLOCK_SIZE, buf, &nread);
 155                 if (rc)
 156                         goto out;
 157                 if (nread != ISO_DEFAULT_BLOCK_SIZE) {
 158                         rc = EIO;
 159                         goto out;
 160                 }
 161                 rc = EINVAL;
 162                 if (memcmp(vd->id, ISO_STANDARD_ID, sizeof vd->id) != 0)
 163                         goto out;
 164                 if (isonum_711(vd->type) == ISO_VD_END)
 165                         goto out;
 166                 if (isonum_711(vd->type) == ISO_VD_PRIMARY)
 167                         break;
 168         }
 169         if (isonum_723(vd->logical_block_size) != ISO_DEFAULT_BLOCK_SIZE)
 170                 goto out;
 171
 172         /* Now get the path table and lookup the directory of the file */
 173         bno = isonum_732(vd->type_m_path_table);
 174         psize = isonum_733(vd->path_table_size);
 175
 176         if (psize > ISO_DEFAULT_BLOCK_SIZE) {
 177                 dealloc(buf, ISO_DEFAULT_BLOCK_SIZE);
 178                 buf = alloc(buf_size = roundup(psize, ISO_DEFAULT_BLOCK_SIZE));
 179         }
 180
 181 #if !defined(LIBSA_NO_TWIDDLE)
 182         twiddle();
 183 #endif
 184         rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
 185                                    buf_size, buf, &nread);
 186         if (rc)
 187                 goto out;
 188         if (nread != buf_size) {
 189                 rc = EIO;
 190                 goto out;
 191         }
 192
 193         parent = 1;
 194         pp = (struct ptable_ent *)buf;
 195         ent = 1;
 196         bno = isonum_732(pp->block) + isonum_711(pp->extlen);
 197
 198         rc = ENOENT;
 199
 200         while (*path) {
 201                 /*
 202                  * Remove extra separators
 203                  */
 204                 while (*path == '/')
 205                         path++;
 206
 207                 if ((char *)pp >= (char *)buf + psize)
 208                         break;
 209                 if (isonum_722(pp->parent) != parent)
 210                         break;
 211                 if (!pnmatch(path, pp)) {
 212                         pp = (struct ptable_ent *)((char *)pp + PTSIZE(pp));
 213                         ent++;
 214                         continue;
 215                 }
 216                 path += isonum_711(pp->namlen) + 1;
 217                 parent = ent;
 218                 bno = isonum_732(pp->block) + isonum_711(pp->extlen);
 219                 while ((char *)pp < (char *)buf + psize) {
 220                         if (isonum_722(pp->parent) == parent)
 221                                 break;
 222                         pp = (struct ptable_ent *)((char *)pp + PTSIZE(pp));
 223                         ent++;
 224                 }
 225         }
 226
 227         /*
 228          * Now bno has the start of the directory that supposedly
 229          * contains the file
 230          */
 231         bno--;
 232         dsize = 1;              /* Something stupid, but > 0 XXX */
 233         for (psize = 0; psize < dsize;) {
 234                 if (!(psize % ISO_DEFAULT_BLOCK_SIZE)) {
 235                         bno++;
 236 #if !defined(LIBSA_NO_TWIDDLE)
 237                         twiddle();
 238 #endif
 239                         rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
 240                                                    cdb2devb(bno),
 241                                                    ISO_DEFAULT_BLOCK_SIZE,
 242                                                    buf, &nread);
 243                         if (rc)
 244                                 goto out;
 245                         if (nread != ISO_DEFAULT_BLOCK_SIZE) {
 246                                 rc = EIO;
 247                                 goto out;
 248                         }
 249                         dp = (struct iso_directory_record *)buf;
 250                 }
 251                 if (!isonum_711(dp->length)) {
 252                         if ((void *)dp == buf)
 253                                 psize += ISO_DEFAULT_BLOCK_SIZE;
 254                         else
 255                                 psize = roundup(psize, ISO_DEFAULT_BLOCK_SIZE);
 256                         continue;
 257                 }
 258                 if (dsize == 1)
 259                         dsize = isonum_733(dp->size);
 260                 if (dirmatch(path, dp))
 261                         break;
 262                 psize += isonum_711(dp->length);
 263                 dp = (struct iso_directory_record *)
 264                         ((char *)dp + isonum_711(dp->length));
 265         }
 266
 267         if (psize >= dsize) {
 268                 rc = ENOENT;
 269                 goto out;
 270         }
 271
 272         /* allocate file system specific data structure */
 273         fp = alloc(sizeof(struct file));
 274         memset(fp, 0, sizeof(struct file));
 275         f->f_fsdata = (void *)fp;
 276
 277         fp->off = 0;
 278         fp->bno = isonum_733(dp->extent);
 279         fp->size = isonum_733(dp->size);
 280         dealloc(buf, buf_size);
 281         fsmod = "cd9660";
 282
 283         return 0;
 284
 285 out:
 286         if (fp)
 287                 dealloc(fp, sizeof(struct file));
 288         dealloc(buf, buf_size);
 289
 290         return rc;
 291 }
 292
 293 #if !defined(LIBSA_NO_FS_CLOSE)
 294 __compactcall int
 295 cd9660_close(struct open_file *f)
 296 {
 297         struct file *fp = (struct file *)f->f_fsdata;
 298
 299         f->f_fsdata = 0;
 300         dealloc(fp, sizeof *fp);
 301
 302         return 0;
 303 }
 304 #endif /* !defined(LIBSA_NO_FS_CLOSE) */
 305
 306 __compactcall int
 307 cd9660_read(struct open_file *f, void *start, size_t size, size_t *resid)
 308 {
 309         struct file *fp = (struct file *)f->f_fsdata;
 310         int rc = 0;
 311         daddr_t bno;
 312         char buf[ISO_DEFAULT_BLOCK_SIZE];
 313         char *dp;
 314         size_t nread, off;
 315
 316         while (size) {
 317                 if (fp->off < 0 || fp->off >= fp->size)
 318                         break;
 319                 bno = fp->off / ISO_DEFAULT_BLOCK_SIZE + fp->bno;
 320                 if (fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1)
 321                     || (fp->off + ISO_DEFAULT_BLOCK_SIZE) > fp->size
 322                     || size < ISO_DEFAULT_BLOCK_SIZE)
 323                         dp = buf;
 324                 else
 325                         dp = start;
 326 #if !defined(LIBSA_NO_TWIDDLE)
 327                 twiddle();
 328 #endif
 329                 rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ, cdb2devb(bno),
 330                                             ISO_DEFAULT_BLOCK_SIZE, dp, &nread);
 331                 if (rc)
 332                         return rc;
 333                 if (nread != ISO_DEFAULT_BLOCK_SIZE)
 334                         return EIO;
 335                 if (dp == buf) {
 336                         off = fp->off & (ISO_DEFAULT_BLOCK_SIZE - 1);
 337                         if (nread > off + size)
 338                                 nread = off + size;
 339                         nread -= off;
 340                         if (nread > fp->size - fp->off)
 341                                 nread = fp->size - fp->off;
 342                         memcpy(start, buf + off, nread);
 343                         start = (char *)start + nread;
 344                         fp->off += nread;
 345                         size -= nread;
 346                 } else {
 347                         start = (char *)start + ISO_DEFAULT_BLOCK_SIZE;
 348                         fp->off += ISO_DEFAULT_BLOCK_SIZE;
 349                         size -= ISO_DEFAULT_BLOCK_SIZE;
 350                 }
 351         }
 352         if(fp->off > fp->size)
 353                 size += fp->off - fp->size;
 354         if (resid)
 355                 *resid = size;
 356         return rc;
 357 }
 358
 359 #if !defined(LIBSA_NO_FS_WRITE)
 360 __compactcall int
 361 cd9660_write(struct open_file *f, void *start, size_t size, size_t *resid)
 362 {
 363
 364         return EROFS;
 365 }
 366 #endif /* !defined(LIBSA_NO_FS_WRITE) */
 367
 368 #if !defined(LIBSA_NO_FS_SEEK)
 369 __compactcall off_t
 370 cd9660_seek(struct open_file *f, off_t offset, int where)
 371 {
 372         struct file *fp = (struct file *)f->f_fsdata;
 373
 374         switch (where) {
 375         case SEEK_SET:
 376                 fp->off = offset;
 377                 break;
 378         case SEEK_CUR:
 379                 fp->off += offset;
 380                 break;
 381         case SEEK_END:
 382                 fp->off = fp->size - offset;
 383                 break;
 384         default:
 385                 return -1;
 386         }
 387         return fp->off;
 388 }
 389 #endif /* !defined(LIBSA_NO_FS_SEEK) */
 390
 391 __compactcall int
 392 cd9660_stat(struct open_file *f, struct stat *sb)
 393 {
 394         struct file *fp = (struct file *)f->f_fsdata;
 395
 396         /* only importatn stuff */
 397         sb->st_mode = S_IFREG | S_IRUSR | S_IRGRP | S_IROTH;
 398         sb->st_uid = sb->st_gid = 0;
 399         sb->st_size = fp->size;
 400         return 0;
 401 }
 402
 403 #if defined(LIBSA_ENABLE_LS_OP)
 404 __compactcall void
 405 cd9660_ls(struct open_file *f, const char *pattern,
 406                 void (*funcp)(char* arg), char* path)
 407 {
 408         printf("Currently ls command is unsupported by cd9660\n");
 409         return;
 410 }
 411 #endif