root/lib/compression/mszip.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. Ziphuft_free
  2. Ziphuft_build
  3. Zipinflate_codes
  4. Zipinflate_stored
  5. Zipinflate_fixed
  6. Zipinflate_dynamic
  7. Zipinflate_block
  8. ZIPdecomp_state
  9. ZIPdecompress

   1 /* mszip decompression - based on cabextract.c code from
   2  * Stuart Caie
   3  *
   4  * adapted for Samba by Andrew Tridgell and Stefan Metzmacher 2005
   5  *
   6  * (C) 2000-2001 Stuart Caie <kyzer@4u.net>
   7  * reaktivate-specifics by Malte Starostik <malte@kde.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 3 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  21  */
  22 
  23 #include "includes.h"
  24 #include "../compression/mszip.h"
  25 
  26 /*--------------------------------------------------------------------------*/
  27 /* our archiver information / state */
  28 
  29 /* MSZIP stuff */
  30 #define ZIPWSIZE        0x8000  /* window size */
  31 #define ZIPLBITS        9       /* bits in base literal/length lookup table */
  32 #define ZIPDBITS        6       /* bits in base distance lookup table */
  33 #define ZIPBMAX         16      /* maximum bit length of any code */
  34 #define ZIPN_MAX        288     /* maximum number of codes in any set */
  35 
  36 struct Ziphuft {
  37   uint8_t e;                /* number of extra bits or operation */
  38   uint8_t b;                /* number of bits in this code or subcode */
  39   union {
  40     uint16_t n;              /* literal, length base, or distance base */
  41     struct Ziphuft *t;    /* pointer to next level of table */
  42   } v;
  43 };
  44 
  45 struct ZIPstate {
  46     uint32_t window_posn;     /* current offset within the window        */
  47     uint32_t bb;              /* bit buffer */
  48     uint32_t bk;              /* bits in bit buffer */
  49     uint32_t ll[288+32];           /* literal/length and distance code lengths */
  50     uint32_t c[ZIPBMAX+1];    /* bit length count table */
  51     int32_t  lx[ZIPBMAX+1];   /* memory for l[-1..ZIPBMAX-1] */
  52     struct Ziphuft *u[ZIPBMAX];                 /* table stack */
  53     uint32_t v[ZIPN_MAX];     /* values in order of bit length */
  54     uint32_t x[ZIPBMAX+1];    /* bit offsets, then code stack */
  55     uint8_t *inpos;
  56 };
  57 
  58 /* generic stuff */
  59 #define CAB(x) (decomp_state->x)
  60 #define ZIP(x) (decomp_state->methods.zip.x)
  61 
  62 /* CAB data blocks are <= 32768 bytes in uncompressed form. Uncompressed
  63  * blocks have zero growth. MSZIP guarantees that it won't grow above
  64  * uncompressed size by more than 12 bytes. LZX guarantees it won't grow
  65  * more than 6144 bytes.
  66  */
  67 #define CAB_BLOCKMAX (32768)
  68 #define CAB_INPUTMAX (CAB_BLOCKMAX+6144)
  69 
  70 struct decomp_state {
  71   struct folder *current; /* current folder we're extracting from  */
  72   uint32_t offset;           /* uncompressed offset within folder     */
  73   uint8_t *outpos;          /* (high level) start of data to use up  */
  74   uint16_t outlen;           /* (high level) amount of data to use up */
  75   uint16_t split;            /* at which split in current folder?     */
  76   int (*decompress)(int, int); /* the chosen compression func      */
  77   uint8_t inbuf[CAB_INPUTMAX+2]; /* +2 for lzx bitbuffer overflows!  */
  78   uint8_t outbuf[CAB_BLOCKMAX];
  79   union {
  80     struct ZIPstate zip;
  81   } methods;
  82 };
  83 
  84 
  85 /* MSZIP decruncher */
  86 
  87 /* Dirk Stoecker wrote the ZIP decoder, based on the InfoZip deflate code */
  88 
  89 /* Tables for deflate from PKZIP's appnote.txt. */
  90 static const uint8_t Zipborder[] = /* Order of the bit length code lengths */
  91 { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
  92 static const uint16_t Zipcplens[] = /* Copy lengths for literal codes 257..285 */
  93 { 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51,
  94  59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0};
  95 static const uint16_t Zipcplext[] = /* Extra bits for literal codes 257..285 */
  96 { 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4,
  97   4, 5, 5, 5, 5, 0, 99, 99}; /* 99==invalid */
  98 static const uint16_t Zipcpdist[] = /* Copy offsets for distance codes 0..29 */
  99 { 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385,
 100 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577};
 101 static const uint16_t Zipcpdext[] = /* Extra bits for distance codes */
 102 { 0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10,
 103 10, 11, 11, 12, 12, 13, 13};
 104 
 105 /* And'ing with Zipmask[n] masks the lower n bits */
 106 static const uint16_t Zipmask[17] = {
 107  0x0000, 0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
 108  0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
 109 };
 110 
 111 #define ZIPNEEDBITS(n) {while(k<(n)){int32_t c=*(ZIP(inpos)++);\
 112     b|=((uint32_t)c)<<k;k+=8;}}
 113 #define ZIPDUMPBITS(n) {b>>=(n);k-=(n);}
 114 
 115 static void Ziphuft_free(struct Ziphuft *t)
     /* [<][>][^][v][top][bottom][index][help] */
 116 {
 117   register struct Ziphuft *p, *q;
 118 
 119   /* Go through linked list, freeing from the allocated (t[-1]) address. */
 120   p = t;
 121   while (p != (struct Ziphuft *)NULL)
 122   {
 123     q = (--p)->v.t;
 124     free(p);
 125     p = q;
 126   }
 127 }
 128 
 129 static int32_t Ziphuft_build(struct decomp_state *decomp_state,
     /* [<][>][^][v][top][bottom][index][help] */
 130                           uint32_t *b, uint32_t n, uint32_t s, const uint16_t *d, const uint16_t *e,
 131                           struct Ziphuft **t, int32_t *m)
 132 {
 133   uint32_t a;                           /* counter for codes of length k */
 134   uint32_t el;                          /* length of EOB code (value 256) */
 135   uint32_t f;                           /* i repeats in table every f entries */
 136   int32_t g;                            /* maximum code length */
 137   int32_t h;                            /* table level */
 138   register uint32_t i;                  /* counter, current code */
 139   register uint32_t j;                  /* counter */
 140   register int32_t k;                   /* number of bits in current code */
 141   int32_t *l;                   /* stack of bits per table */
 142   register uint32_t *p;                 /* pointer into ZIP(c)[],ZIP(b)[],ZIP(v)[] */
 143   register struct Ziphuft *q;   /* points to current table */
 144   struct Ziphuft r;             /* table entry for structure assignment */
 145   register int32_t w;              /* bits before this table == (l * h) */
 146   uint32_t *xp;                         /* pointer into x */
 147   int32_t y;                       /* number of dummy codes added */
 148   uint32_t z;                           /* number of entries in current table */
 149 
 150   l = ZIP(lx)+1;
 151 
 152   /* Generate counts for each bit length */
 153   el = n > 256 ? b[256] : ZIPBMAX; /* set length of EOB code, if any */
 154 
 155   for(i = 0; i < ZIPBMAX+1; ++i)
 156     ZIP(c)[i] = 0;
 157   p = b;  i = n;
 158   do
 159   {
 160     ZIP(c)[*p]++; p++;               /* assume all entries <= ZIPBMAX */
 161   } while (--i);
 162   if (ZIP(c)[0] == n)                /* null input--all zero length codes */
 163   {
 164     *t = (struct Ziphuft *)NULL;
 165     *m = 0;
 166     return 0;
 167   }
 168 
 169   /* Find minimum and maximum length, bound *m by those */
 170   for (j = 1; j <= ZIPBMAX; j++)
 171     if (ZIP(c)[j])
 172       break;
 173   k = j;                        /* minimum code length */
 174   if ((uint32_t)*m < j)
 175     *m = j;
 176   for (i = ZIPBMAX; i; i--)
 177     if (ZIP(c)[i])
 178       break;
 179   g = i;                        /* maximum code length */
 180   if ((uint32_t)*m > i)
 181     *m = i;
 182 
 183   /* Adjust last length count to fill out codes, if needed */
 184   for (y = 1 << j; j < i; j++, y <<= 1)
 185     if ((y -= ZIP(c)[j]) < 0)
 186       return 2;                 /* bad input: more codes than bits */
 187   if ((y -= ZIP(c)[i]) < 0)
 188     return 2;
 189   ZIP(c)[i] += y;
 190 
 191   /* Generate starting offsets int32_to the value table for each length */
 192   ZIP(x)[1] = j = 0;
 193   p = ZIP(c) + 1;  xp = ZIP(x) + 2;
 194   while (--i)
 195   {                 /* note that i == g from above */
 196     *xp++ = (j += *p++);
 197   }
 198 
 199   /* Make a table of values in order of bit lengths */
 200   p = b;  i = 0;
 201   do{
 202     if ((j = *p++) != 0)
 203       ZIP(v)[ZIP(x)[j]++] = i;
 204   } while (++i < n);
 205 
 206 
 207   /* Generate the Huffman codes and for each, make the table entries */
 208   ZIP(x)[0] = i = 0;                 /* first Huffman code is zero */
 209   p = ZIP(v);                        /* grab values in bit order */
 210   h = -1;                       /* no tables yet--level -1 */
 211   w = l[-1] = 0;                /* no bits decoded yet */
 212   ZIP(u)[0] = (struct Ziphuft *)NULL;   /* just to keep compilers happy */
 213   q = (struct Ziphuft *)NULL;      /* ditto */
 214   z = 0;                        /* ditto */
 215 
 216   /* go through the bit lengths (k already is bits in shortest code) */
 217   for (; k <= g; k++)
 218   {
 219     a = ZIP(c)[k];
 220     while (a--)
 221     {
 222       /* here i is the Huffman code of length k bits for value *p */
 223       /* make tables up to required level */
 224       while (k > w + l[h])
 225       {
 226         w += l[h++];            /* add bits already decoded */
 227 
 228         /* compute minimum size table less than or equal to *m bits */
 229         z = (z = g - w) > (uint32_t)*m ? *m : z;        /* upper limit */
 230         if ((f = 1 << (j = k - w)) > a + 1)     /* try a k-w bit table */
 231         {                       /* too few codes for k-w bit table */
 232           f -= a + 1;           /* deduct codes from patterns left */
 233           xp = ZIP(c) + k;
 234           while (++j < z)       /* try smaller tables up to z bits */
 235           {
 236             if ((f <<= 1) <= *++xp)
 237               break;            /* enough codes to use up j bits */
 238             f -= *xp;           /* else deduct codes from patterns */
 239           }
 240         }
 241         if ((uint32_t)w + j > el && (uint32_t)w < el)
 242           j = el - w;           /* make EOB code end at table */
 243         z = 1 << j;             /* table entries for j-bit table */
 244         l[h] = j;               /* set table size in stack */
 245 
 246         /* allocate and link in new table */
 247         if (!(q = (struct Ziphuft *)SMB_MALLOC((z + 1)*sizeof(struct Ziphuft))))
 248         {
 249           if(h)
 250             Ziphuft_free(ZIP(u)[0]);
 251           return 3;             /* not enough memory */
 252         }
 253         *t = q + 1;             /* link to list for Ziphuft_free() */
 254         *(t = &(q->v.t)) = (struct Ziphuft *)NULL;
 255         ZIP(u)[h] = ++q;             /* table starts after link */
 256 
 257         /* connect to last table, if there is one */
 258         if (h)
 259         {
 260           ZIP(x)[h] = i;             /* save pattern for backing up */
 261           r.b = (uint8_t)l[h-1];    /* bits to dump before this table */
 262           r.e = (uint8_t)(16 + j);  /* bits in this table */
 263           r.v.t = q;            /* pointer to this table */
 264           j = (i & ((1 << w) - 1)) >> (w - l[h-1]);
 265           ZIP(u)[h-1][j] = r;        /* connect to last table */
 266         }
 267       }
 268 
 269       /* set up table entry in r */
 270       r.b = (uint8_t)(k - w);
 271       if (p >= ZIP(v) + n)
 272         r.e = 99;               /* out of values--invalid code */
 273       else if (*p < s)
 274       {
 275         r.e = (uint8_t)(*p < 256 ? 16 : 15);    /* 256 is end-of-block code */
 276         r.v.n = *p++;           /* simple code is just the value */
 277       }
 278       else
 279       {
 280         r.e = (uint8_t)e[*p - s];   /* non-simple--look up in lists */
 281         r.v.n = d[*p++ - s];
 282       }
 283 
 284       /* fill code-like entries with r */
 285       f = 1 << (k - w);
 286       for (j = i >> w; j < z; j += f)
 287         q[j] = r;
 288 
 289       /* backwards increment the k-bit code i */
 290       for (j = 1 << (k - 1); i & j; j >>= 1)
 291         i ^= j;
 292       i ^= j;
 293 
 294       /* backup over finished tables */
 295       while ((i & ((1 << w) - 1)) != ZIP(x)[h])
 296         w -= l[--h];            /* don't need to update q */
 297     }
 298   }
 299 
 300   /* return actual size of base table */
 301   *m = l[0];
 302 
 303   /* Return true (1) if we were given an incomplete table */
 304   return y != 0 && g != 1;
 305 }
 306 
 307 static int32_t Zipinflate_codes(struct decomp_state *decomp_state,
     /* [<][>][^][v][top][bottom][index][help] */
 308                              struct Ziphuft *tl, struct Ziphuft *td,
 309                              int32_t bl, int32_t bd)
 310 {
 311   register uint32_t e;  /* table entry flag/number of extra bits */
 312   uint32_t n, d;        /* length and index for copy */
 313   uint32_t w;           /* current window position */
 314   struct Ziphuft *t; /* pointer to table entry */
 315   uint32_t ml, md;      /* masks for bl and bd bits */
 316   register uint32_t b;  /* bit buffer */
 317   register uint32_t k;  /* number of bits in bit buffer */
 318 
 319   DEBUG(10,("Zipinflate_codes\n"));
 320 
 321   /* make local copies of globals */
 322   b = ZIP(bb);                       /* initialize bit buffer */
 323   k = ZIP(bk);
 324   w = ZIP(window_posn);                       /* initialize window position */
 325 
 326   /* inflate the coded data */
 327   ml = Zipmask[bl];             /* precompute masks for speed */
 328   md = Zipmask[bd];
 329 
 330   for(;;)
 331   {
 332     ZIPNEEDBITS((uint32_t)bl)
 333     if((e = (t = tl + ((uint32_t)b & ml))->e) > 16)
 334       do
 335       {
 336         if (e == 99)
 337           return 1;
 338         ZIPDUMPBITS(t->b)
 339         e -= 16;
 340         ZIPNEEDBITS(e)
 341       } while ((e = (t = t->v.t + ((uint32_t)b & Zipmask[e]))->e) > 16);
 342     ZIPDUMPBITS(t->b)
 343     if (w >= CAB_BLOCKMAX) break;
 344     if (e == 16)                /* then it's a literal */
 345       CAB(outbuf)[w++] = (uint8_t)t->v.n;
 346     else                        /* it's an EOB or a length */
 347     {
 348       /* exit if end of block */
 349       if(e == 15)
 350         break;
 351 
 352       /* get length of block to copy */
 353       ZIPNEEDBITS(e)
 354       n = t->v.n + ((uint32_t)b & Zipmask[e]);
 355       ZIPDUMPBITS(e);
 356 
 357       /* decode distance of block to copy */
 358       ZIPNEEDBITS((uint32_t)bd)
 359       if ((e = (t = td + ((uint32_t)b & md))->e) > 16)
 360         do {
 361           if (e == 99)
 362             return 1;
 363           ZIPDUMPBITS(t->b)
 364           e -= 16;
 365           ZIPNEEDBITS(e)
 366         } while ((e = (t = t->v.t + ((uint32_t)b & Zipmask[e]))->e) > 16);
 367       ZIPDUMPBITS(t->b)
 368       ZIPNEEDBITS(e)
 369       d = w - t->v.n - ((uint32_t)b & Zipmask[e]);
 370       ZIPDUMPBITS(e)
 371       do
 372       {
 373         n -= (e = (e = ZIPWSIZE - ((d &= ZIPWSIZE-1) > w ? d : w)) > n ?n:e);
 374         do
 375         {
 376           CAB(outbuf)[w++] = CAB(outbuf)[d++];
 377         } while (--e);
 378       } while (n);
 379     }
 380   }
 381 
 382   /* restore the globals from the locals */
 383   ZIP(window_posn) = w;              /* restore global window pointer */
 384   ZIP(bb) = b;                       /* restore global bit buffer */
 385   ZIP(bk) = k;
 386 
 387   /* done */
 388   return 0;
 389 }
 390 
 391 /* "decompress" an inflated type 0 (stored) block. */
 392 static int32_t Zipinflate_stored(struct decomp_state *decomp_state)
     /* [<][>][^][v][top][bottom][index][help] */
 393 {
 394   uint32_t n;           /* number of bytes in block */
 395   uint32_t w;           /* current window position */
 396   register uint32_t b;  /* bit buffer */
 397   register uint32_t k;  /* number of bits in bit buffer */
 398 
 399   /* make local copies of globals */
 400   b = ZIP(bb);                       /* initialize bit buffer */
 401   k = ZIP(bk);
 402   w = ZIP(window_posn);              /* initialize window position */
 403 
 404   /* go to byte boundary */
 405   n = k & 7;
 406   ZIPDUMPBITS(n);
 407 
 408   /* get the length and its complement */
 409   ZIPNEEDBITS(16)
 410   n = ((uint32_t)b & 0xffff);
 411   ZIPDUMPBITS(16)
 412   ZIPNEEDBITS(16)
 413   if (n != (uint32_t)((~b) & 0xffff))
 414     return 1;                   /* error in compressed data */
 415   ZIPDUMPBITS(16)
 416 
 417   /* read and output the compressed data */
 418   while(n--)
 419   {
 420     ZIPNEEDBITS(8)
 421     CAB(outbuf)[w++] = (uint8_t)b;
 422     ZIPDUMPBITS(8)
 423   }
 424 
 425   /* restore the globals from the locals */
 426   ZIP(window_posn) = w;              /* restore global window pointer */
 427   ZIP(bb) = b;                       /* restore global bit buffer */
 428   ZIP(bk) = k;
 429   return 0;
 430 }
 431 
 432 static int32_t Zipinflate_fixed(struct decomp_state *decomp_state)
     /* [<][>][^][v][top][bottom][index][help] */
 433 {
 434   struct Ziphuft *fixed_tl;
 435   struct Ziphuft *fixed_td;
 436   int32_t fixed_bl, fixed_bd;
 437   int32_t i;                /* temporary variable */
 438   uint32_t *l;
 439 
 440   l = ZIP(ll);
 441 
 442   /* literal table */
 443   for(i = 0; i < 144; i++)
 444     l[i] = 8;
 445   for(; i < 256; i++)
 446     l[i] = 9;
 447   for(; i < 280; i++)
 448     l[i] = 7;
 449   for(; i < 288; i++)          /* make a complete, but wrong code set */
 450     l[i] = 8;
 451   fixed_bl = 7;
 452   if((i = Ziphuft_build(decomp_state, l, 288, 257, Zipcplens, Zipcplext, &fixed_tl, &fixed_bl)))
 453     return i;
 454 
 455   /* distance table */
 456   for(i = 0; i < 30; i++)      /* make an incomplete code set */
 457     l[i] = 5;
 458   fixed_bd = 5;
 459   if((i = Ziphuft_build(decomp_state, l, 30, 0, Zipcpdist, Zipcpdext, &fixed_td, &fixed_bd)) > 1)
 460   {
 461     Ziphuft_free(fixed_tl);
 462     return i;
 463   }
 464 
 465   /* decompress until an end-of-block code */
 466   i = Zipinflate_codes(decomp_state, fixed_tl, fixed_td, fixed_bl, fixed_bd);
 467 
 468   Ziphuft_free(fixed_td);
 469   Ziphuft_free(fixed_tl);
 470   return i;
 471 }
 472 
 473 /* decompress an inflated type 2 (dynamic Huffman codes) block. */
 474 static int32_t Zipinflate_dynamic(struct decomp_state *decomp_state)
     /* [<][>][^][v][top][bottom][index][help] */
 475 {
 476   int32_t i;            /* temporary variables */
 477   uint32_t j;
 478   uint32_t *ll;
 479   uint32_t l;                   /* last length */
 480   uint32_t m;                   /* mask for bit lengths table */
 481   uint32_t n;                   /* number of lengths to get */
 482   struct Ziphuft *tl;      /* literal/length code table */
 483   struct Ziphuft *td;      /* distance code table */
 484   int32_t bl;              /* lookup bits for tl */
 485   int32_t bd;              /* lookup bits for td */
 486   uint32_t nb;                  /* number of bit length codes */
 487   uint32_t nl;                  /* number of literal/length codes */
 488   uint32_t nd;                  /* number of distance codes */
 489   register uint32_t b;     /* bit buffer */
 490   register uint32_t k;  /* number of bits in bit buffer */
 491 
 492   /* make local bit buffer */
 493   b = ZIP(bb);
 494   k = ZIP(bk);
 495   ll = ZIP(ll);
 496 
 497   /* read in table lengths */
 498   ZIPNEEDBITS(5)
 499   nl = 257 + ((uint32_t)b & 0x1f);      /* number of literal/length codes */
 500   ZIPDUMPBITS(5)
 501   ZIPNEEDBITS(5)
 502   nd = 1 + ((uint32_t)b & 0x1f);        /* number of distance codes */
 503   ZIPDUMPBITS(5)
 504   ZIPNEEDBITS(4)
 505   nb = 4 + ((uint32_t)b & 0xf);         /* number of bit length codes */
 506   ZIPDUMPBITS(4)
 507   if(nl > 288 || nd > 32)
 508     return 1;                   /* bad lengths */
 509 
 510   /* read in bit-length-code lengths */
 511   for(j = 0; j < nb; j++)
 512   {
 513     ZIPNEEDBITS(3)
 514     ll[Zipborder[j]] = (uint32_t)b & 7;
 515     ZIPDUMPBITS(3)
 516   }
 517   for(; j < 19; j++)
 518     ll[Zipborder[j]] = 0;
 519 
 520   /* build decoding table for trees--single level, 7 bit lookup */
 521   bl = 7;
 522   if((i = Ziphuft_build(decomp_state, ll, 19, 19, NULL, NULL, &tl, &bl)) != 0)
 523   {
 524     if(i == 1)
 525       Ziphuft_free(tl);
 526     return i;                   /* incomplete code set */
 527   }
 528 
 529   /* read in literal and distance code lengths */
 530   n = nl + nd;
 531   m = Zipmask[bl];
 532   i = l = 0;
 533   while((uint32_t)i < n)
 534   {
 535     ZIPNEEDBITS((uint32_t)bl)
 536     j = (td = tl + ((uint32_t)b & m))->b;
 537     ZIPDUMPBITS(j)
 538     j = td->v.n;
 539     if (j < 16)                 /* length of code in bits (0..15) */
 540       ll[i++] = l = j;          /* save last length in l */
 541     else if (j == 16)           /* repeat last length 3 to 6 times */
 542     {
 543       ZIPNEEDBITS(2)
 544       j = 3 + ((uint32_t)b & 3);
 545       ZIPDUMPBITS(2)
 546       if((uint32_t)i + j > n)
 547         return 1;
 548       while (j--)
 549         ll[i++] = l;
 550     }
 551     else if (j == 17)           /* 3 to 10 zero length codes */
 552     {
 553       ZIPNEEDBITS(3)
 554       j = 3 + ((uint32_t)b & 7);
 555       ZIPDUMPBITS(3)
 556       if ((uint32_t)i + j > n)
 557         return 1;
 558       while (j--)
 559         ll[i++] = 0;
 560       l = 0;
 561     }
 562     else                        /* j == 18: 11 to 138 zero length codes */
 563     {
 564       ZIPNEEDBITS(7)
 565       j = 11 + ((uint32_t)b & 0x7f);
 566       ZIPDUMPBITS(7)
 567       if ((uint32_t)i + j > n)
 568         return 1;
 569       while (j--)
 570         ll[i++] = 0;
 571       l = 0;
 572     }
 573   }
 574 
 575   /* free decoding table for trees */
 576   Ziphuft_free(tl);
 577 
 578   /* restore the global bit buffer */
 579   ZIP(bb) = b;
 580   ZIP(bk) = k;
 581 
 582   /* build the decoding tables for literal/length and distance codes */
 583   bl = ZIPLBITS;
 584   if((i = Ziphuft_build(decomp_state, ll, nl, 257, Zipcplens, Zipcplext, &tl, &bl)) != 0)
 585   {
 586     if(i == 1)
 587       Ziphuft_free(tl);
 588     return i;                   /* incomplete code set */
 589   }
 590   bd = ZIPDBITS;
 591   Ziphuft_build(decomp_state, ll + nl, nd, 0, Zipcpdist, Zipcpdext, &td, &bd);
 592 
 593   /* decompress until an end-of-block code */
 594   if(Zipinflate_codes(decomp_state, tl, td, bl, bd))
 595     return 1;
 596 
 597   /* free the decoding tables, return */
 598   Ziphuft_free(tl);
 599   Ziphuft_free(td);
 600   return 0;
 601 }
 602 
 603 /* e == last block flag */
 604 static int32_t Zipinflate_block(struct decomp_state *decomp_state, int32_t *e)
     /* [<][>][^][v][top][bottom][index][help] */
 605 { /* decompress an inflated block */
 606   uint32_t t;                   /* block type */
 607   register uint32_t b;     /* bit buffer */
 608   register uint32_t k;     /* number of bits in bit buffer */
 609 
 610   DEBUG(10,("Zipinflate_block\n"));
 611 
 612   /* make local bit buffer */
 613   b = ZIP(bb);
 614   k = ZIP(bk);
 615 
 616   /* read in last block bit */
 617   ZIPNEEDBITS(1)
 618   *e = (int32_t)b & 1;
 619   ZIPDUMPBITS(1)
 620 
 621   /* read in block type */
 622   ZIPNEEDBITS(2)
 623   t = (uint32_t)b & 3;
 624   ZIPDUMPBITS(2)
 625 
 626   /* restore the global bit buffer */
 627   ZIP(bb) = b;
 628   ZIP(bk) = k;
 629 
 630   DEBUG(10,("inflate type %d\n", t));
 631 
 632   /* inflate that block type */
 633   if(t == 2)
 634     return Zipinflate_dynamic(decomp_state);
 635   if(t == 0)
 636     return Zipinflate_stored(decomp_state);
 637   if(t == 1)
 638     return Zipinflate_fixed(decomp_state);
 639   /* bad block type */
 640   return 2;
 641 }
 642 
 643 _PUBLIC_ struct decomp_state *ZIPdecomp_state(TALLOC_CTX *mem_ctx)
     /* [<][>][^][v][top][bottom][index][help] */
 644 {
 645         return talloc_zero(mem_ctx, struct decomp_state);
 646 }
 647 
 648 int ZIPdecompress(struct decomp_state *decomp_state, DATA_BLOB *inbuf, DATA_BLOB *outbuf)
     /* [<][>][^][v][top][bottom][index][help] */
 649 {
 650         int32_t e = 0;/* last block flag */
 651 
 652         ZIP(inpos) = CAB(inbuf);
 653         ZIP(bb) = ZIP(bk) = ZIP(window_posn) = 0;
 654 
 655         if (inbuf->length > sizeof(decomp_state->inbuf)) return DECR_INPUT;
 656 
 657         if (outbuf->length > sizeof(decomp_state->outbuf)) return DECR_OUTPUT;
 658 
 659         if (outbuf->length > ZIPWSIZE) return DECR_DATAFORMAT;
 660 
 661         memcpy(decomp_state->inbuf, inbuf->data, inbuf->length);
 662 
 663         /* CK = Chris Kirmse, official Microsoft purloiner */
 664         if (ZIP(inpos)[0] != 'C' || ZIP(inpos)[1] != 'K') return DECR_ILLEGALDATA;
 665         ZIP(inpos) += 2;
 666 
 667         while (!e) {
 668                 if (Zipinflate_block(decomp_state, &e)) {
 669                         return DECR_ILLEGALDATA;
 670                 }
 671         }
 672 
 673         memcpy(outbuf->data, decomp_state->outbuf, outbuf->length);
 674 
 675         return DECR_OK;
 676 }

/* [<][>][^][v][top][bottom][index][help] */