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1 : : /* inflate.c -- zlib decompression
2 : : * Copyright (C) 1995-2005 Mark Adler
3 : : * For conditions of distribution and use, see copyright notice in zlib.h
4 : : *
5 : : * Based on zlib 1.2.3 but modified for the Linux Kernel by
6 : : * Richard Purdie <richard@openedhand.com>
7 : : *
8 : : * Changes mainly for static instead of dynamic memory allocation
9 : : *
10 : : */
11 : :
12 : : #include <linux/zutil.h>
13 : : #include "inftrees.h"
14 : : #include "inflate.h"
15 : : #include "inffast.h"
16 : : #include "infutil.h"
17 : :
18 : 0 : int zlib_inflate_workspacesize(void)
19 : : {
20 : 0 : return sizeof(struct inflate_workspace);
21 : : }
22 : :
23 : 0 : int zlib_inflateReset(z_streamp strm)
24 : : {
25 : : struct inflate_state *state;
26 : :
27 [ # # ][ # # ]: 0 : if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
28 : : state = (struct inflate_state *)strm->state;
29 : 0 : strm->total_in = strm->total_out = state->total = 0;
30 : 0 : strm->msg = NULL;
31 : 0 : strm->adler = 1; /* to support ill-conceived Java test suite */
32 : 0 : state->mode = HEAD;
33 : 0 : state->last = 0;
34 : 0 : state->havedict = 0;
35 : 0 : state->dmax = 32768U;
36 : 0 : state->hold = 0;
37 : 0 : state->bits = 0;
38 : 0 : state->lencode = state->distcode = state->next = state->codes;
39 : :
40 : : /* Initialise Window */
41 : 0 : state->wsize = 1U << state->wbits;
42 : 0 : state->write = 0;
43 : 0 : state->whave = 0;
44 : :
45 : 0 : return Z_OK;
46 : : }
47 : :
48 : : #if 0
49 : : int zlib_inflatePrime(z_streamp strm, int bits, int value)
50 : : {
51 : : struct inflate_state *state;
52 : :
53 : : if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
54 : : state = (struct inflate_state *)strm->state;
55 : : if (bits > 16 || state->bits + bits > 32) return Z_STREAM_ERROR;
56 : : value &= (1L << bits) - 1;
57 : : state->hold += value << state->bits;
58 : : state->bits += bits;
59 : : return Z_OK;
60 : : }
61 : : #endif
62 : :
63 : 0 : int zlib_inflateInit2(z_streamp strm, int windowBits)
64 : : {
65 : : struct inflate_state *state;
66 : :
67 [ # # ]: 0 : if (strm == NULL) return Z_STREAM_ERROR;
68 : 0 : strm->msg = NULL; /* in case we return an error */
69 : :
70 : 0 : state = &WS(strm)->inflate_state;
71 : 0 : strm->state = (struct internal_state *)state;
72 : :
73 [ # # ]: 0 : if (windowBits < 0) {
74 : 0 : state->wrap = 0;
75 : 0 : windowBits = -windowBits;
76 : : }
77 : : else {
78 : 0 : state->wrap = (windowBits >> 4) + 1;
79 : : }
80 [ # # ]: 0 : if (windowBits < 8 || windowBits > 15) {
81 : : return Z_STREAM_ERROR;
82 : : }
83 : 0 : state->wbits = (unsigned)windowBits;
84 : 0 : state->window = &WS(strm)->working_window[0];
85 : :
86 : 0 : return zlib_inflateReset(strm);
87 : : }
88 : :
89 : : /*
90 : : Return state with length and distance decoding tables and index sizes set to
91 : : fixed code decoding. This returns fixed tables from inffixed.h.
92 : : */
93 : : static void zlib_fixedtables(struct inflate_state *state)
94 : : {
95 : : # include "inffixed.h"
96 : 0 : state->lencode = lenfix;
97 : 0 : state->lenbits = 9;
98 : 0 : state->distcode = distfix;
99 : 0 : state->distbits = 5;
100 : : }
101 : :
102 : :
103 : : /*
104 : : Update the window with the last wsize (normally 32K) bytes written before
105 : : returning. This is only called when a window is already in use, or when
106 : : output has been written during this inflate call, but the end of the deflate
107 : : stream has not been reached yet. It is also called to window dictionary data
108 : : when a dictionary is loaded.
109 : :
110 : : Providing output buffers larger than 32K to inflate() should provide a speed
111 : : advantage, since only the last 32K of output is copied to the sliding window
112 : : upon return from inflate(), and since all distances after the first 32K of
113 : : output will fall in the output data, making match copies simpler and faster.
114 : : The advantage may be dependent on the size of the processor's data caches.
115 : : */
116 : 0 : static void zlib_updatewindow(z_streamp strm, unsigned out)
117 : : {
118 : : struct inflate_state *state;
119 : : unsigned copy, dist;
120 : :
121 : 0 : state = (struct inflate_state *)strm->state;
122 : :
123 : : /* copy state->wsize or less output bytes into the circular window */
124 : 0 : copy = out - strm->avail_out;
125 [ # # ]: 0 : if (copy >= state->wsize) {
126 : 0 : memcpy(state->window, strm->next_out - state->wsize, state->wsize);
127 : 0 : state->write = 0;
128 : 0 : state->whave = state->wsize;
129 : : }
130 : : else {
131 : 0 : dist = state->wsize - state->write;
132 [ # # ]: 0 : if (dist > copy) dist = copy;
133 : 0 : memcpy(state->window + state->write, strm->next_out - copy, dist);
134 : 0 : copy -= dist;
135 [ # # ]: 0 : if (copy) {
136 : 0 : memcpy(state->window, strm->next_out - copy, copy);
137 : 0 : state->write = copy;
138 : 0 : state->whave = state->wsize;
139 : : }
140 : : else {
141 : 0 : state->write += dist;
142 [ # # ]: 0 : if (state->write == state->wsize) state->write = 0;
143 [ # # ]: 0 : if (state->whave < state->wsize) state->whave += dist;
144 : : }
145 : : }
146 : 0 : }
147 : :
148 : :
149 : : /*
150 : : * At the end of a Deflate-compressed PPP packet, we expect to have seen
151 : : * a `stored' block type value but not the (zero) length bytes.
152 : : */
153 : : /*
154 : : Returns true if inflate is currently at the end of a block generated by
155 : : Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
156 : : implementation to provide an additional safety check. PPP uses
157 : : Z_SYNC_FLUSH but removes the length bytes of the resulting empty stored
158 : : block. When decompressing, PPP checks that at the end of input packet,
159 : : inflate is waiting for these length bytes.
160 : : */
161 : : static int zlib_inflateSyncPacket(z_streamp strm)
162 : : {
163 : : struct inflate_state *state;
164 : :
165 [ # # ][ # # ]: 0 : if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
166 : : state = (struct inflate_state *)strm->state;
167 : :
168 [ # # ][ # # ]: 0 : if (state->mode == STORED && state->bits == 0) {
169 : 0 : state->mode = TYPE;
170 : : return Z_OK;
171 : : }
172 : : return Z_DATA_ERROR;
173 : : }
174 : :
175 : : /* Macros for inflate(): */
176 : :
177 : : /* check function to use adler32() for zlib or crc32() for gzip */
178 : : #define UPDATE(check, buf, len) zlib_adler32(check, buf, len)
179 : :
180 : : /* Load registers with state in inflate() for speed */
181 : : #define LOAD() \
182 : : do { \
183 : : put = strm->next_out; \
184 : : left = strm->avail_out; \
185 : : next = strm->next_in; \
186 : : have = strm->avail_in; \
187 : : hold = state->hold; \
188 : : bits = state->bits; \
189 : : } while (0)
190 : :
191 : : /* Restore state from registers in inflate() */
192 : : #define RESTORE() \
193 : : do { \
194 : : strm->next_out = put; \
195 : : strm->avail_out = left; \
196 : : strm->next_in = next; \
197 : : strm->avail_in = have; \
198 : : state->hold = hold; \
199 : : state->bits = bits; \
200 : : } while (0)
201 : :
202 : : /* Clear the input bit accumulator */
203 : : #define INITBITS() \
204 : : do { \
205 : : hold = 0; \
206 : : bits = 0; \
207 : : } while (0)
208 : :
209 : : /* Get a byte of input into the bit accumulator, or return from inflate()
210 : : if there is no input available. */
211 : : #define PULLBYTE() \
212 : : do { \
213 : : if (have == 0) goto inf_leave; \
214 : : have--; \
215 : : hold += (unsigned long)(*next++) << bits; \
216 : : bits += 8; \
217 : : } while (0)
218 : :
219 : : /* Assure that there are at least n bits in the bit accumulator. If there is
220 : : not enough available input to do that, then return from inflate(). */
221 : : #define NEEDBITS(n) \
222 : : do { \
223 : : while (bits < (unsigned)(n)) \
224 : : PULLBYTE(); \
225 : : } while (0)
226 : :
227 : : /* Return the low n bits of the bit accumulator (n < 16) */
228 : : #define BITS(n) \
229 : : ((unsigned)hold & ((1U << (n)) - 1))
230 : :
231 : : /* Remove n bits from the bit accumulator */
232 : : #define DROPBITS(n) \
233 : : do { \
234 : : hold >>= (n); \
235 : : bits -= (unsigned)(n); \
236 : : } while (0)
237 : :
238 : : /* Remove zero to seven bits as needed to go to a byte boundary */
239 : : #define BYTEBITS() \
240 : : do { \
241 : : hold >>= bits & 7; \
242 : : bits -= bits & 7; \
243 : : } while (0)
244 : :
245 : : /* Reverse the bytes in a 32-bit value */
246 : : #define REVERSE(q) \
247 : : ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \
248 : : (((q) & 0xff00) << 8) + (((q) & 0xff) << 24))
249 : :
250 : : /*
251 : : inflate() uses a state machine to process as much input data and generate as
252 : : much output data as possible before returning. The state machine is
253 : : structured roughly as follows:
254 : :
255 : : for (;;) switch (state) {
256 : : ...
257 : : case STATEn:
258 : : if (not enough input data or output space to make progress)
259 : : return;
260 : : ... make progress ...
261 : : state = STATEm;
262 : : break;
263 : : ...
264 : : }
265 : :
266 : : so when inflate() is called again, the same case is attempted again, and
267 : : if the appropriate resources are provided, the machine proceeds to the
268 : : next state. The NEEDBITS() macro is usually the way the state evaluates
269 : : whether it can proceed or should return. NEEDBITS() does the return if
270 : : the requested bits are not available. The typical use of the BITS macros
271 : : is:
272 : :
273 : : NEEDBITS(n);
274 : : ... do something with BITS(n) ...
275 : : DROPBITS(n);
276 : :
277 : : where NEEDBITS(n) either returns from inflate() if there isn't enough
278 : : input left to load n bits into the accumulator, or it continues. BITS(n)
279 : : gives the low n bits in the accumulator. When done, DROPBITS(n) drops
280 : : the low n bits off the accumulator. INITBITS() clears the accumulator
281 : : and sets the number of available bits to zero. BYTEBITS() discards just
282 : : enough bits to put the accumulator on a byte boundary. After BYTEBITS()
283 : : and a NEEDBITS(8), then BITS(8) would return the next byte in the stream.
284 : :
285 : : NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return
286 : : if there is no input available. The decoding of variable length codes uses
287 : : PULLBYTE() directly in order to pull just enough bytes to decode the next
288 : : code, and no more.
289 : :
290 : : Some states loop until they get enough input, making sure that enough
291 : : state information is maintained to continue the loop where it left off
292 : : if NEEDBITS() returns in the loop. For example, want, need, and keep
293 : : would all have to actually be part of the saved state in case NEEDBITS()
294 : : returns:
295 : :
296 : : case STATEw:
297 : : while (want < need) {
298 : : NEEDBITS(n);
299 : : keep[want++] = BITS(n);
300 : : DROPBITS(n);
301 : : }
302 : : state = STATEx;
303 : : case STATEx:
304 : :
305 : : As shown above, if the next state is also the next case, then the break
306 : : is omitted.
307 : :
308 : : A state may also return if there is not enough output space available to
309 : : complete that state. Those states are copying stored data, writing a
310 : : literal byte, and copying a matching string.
311 : :
312 : : When returning, a "goto inf_leave" is used to update the total counters,
313 : : update the check value, and determine whether any progress has been made
314 : : during that inflate() call in order to return the proper return code.
315 : : Progress is defined as a change in either strm->avail_in or strm->avail_out.
316 : : When there is a window, goto inf_leave will update the window with the last
317 : : output written. If a goto inf_leave occurs in the middle of decompression
318 : : and there is no window currently, goto inf_leave will create one and copy
319 : : output to the window for the next call of inflate().
320 : :
321 : : In this implementation, the flush parameter of inflate() only affects the
322 : : return code (per zlib.h). inflate() always writes as much as possible to
323 : : strm->next_out, given the space available and the provided input--the effect
324 : : documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers
325 : : the allocation of and copying into a sliding window until necessary, which
326 : : provides the effect documented in zlib.h for Z_FINISH when the entire input
327 : : stream available. So the only thing the flush parameter actually does is:
328 : : when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it
329 : : will return Z_BUF_ERROR if it has not reached the end of the stream.
330 : : */
331 : :
332 : 0 : int zlib_inflate(z_streamp strm, int flush)
333 : : {
334 : : struct inflate_state *state;
335 : : const unsigned char *next; /* next input */
336 : : unsigned char *put; /* next output */
337 : : unsigned have, left; /* available input and output */
338 : : unsigned long hold; /* bit buffer */
339 : : unsigned bits; /* bits in bit buffer */
340 : : unsigned in, out; /* save starting available input and output */
341 : : unsigned copy; /* number of stored or match bytes to copy */
342 : : unsigned char *from; /* where to copy match bytes from */
343 : : code this; /* current decoding table entry */
344 : : code last; /* parent table entry */
345 : : unsigned len; /* length to copy for repeats, bits to drop */
346 : : int ret; /* return code */
347 : : static const unsigned short order[19] = /* permutation of code lengths */
348 : : {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15};
349 : :
350 : : /* Do not check for strm->next_out == NULL here as ppc zImage
351 : : inflates to strm->next_out = 0 */
352 : :
353 [ # # ][ # # ]: 0 : if (strm == NULL || strm->state == NULL ||
[ # # ]
354 [ # # ]: 0 : (strm->next_in == NULL && strm->avail_in != 0))
355 : : return Z_STREAM_ERROR;
356 : :
357 : : state = (struct inflate_state *)strm->state;
358 : :
359 [ # # ]: 0 : if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */
360 : 0 : LOAD();
361 : : in = have;
362 : : out = left;
363 : : ret = Z_OK;
364 : : for (;;)
365 [ # # # # : 0 : switch (state->mode) {
# # # # #
# # # # #
# # # # #
# # ]
366 : : case HEAD:
367 [ # # ]: 0 : if (state->wrap == 0) {
368 : 0 : state->mode = TYPEDO;
369 : 0 : break;
370 : : }
371 [ # # ][ # # ]: 0 : NEEDBITS(16);
372 [ # # ]: 0 : if (
373 : 0 : ((BITS(8) << 8) + (hold >> 8)) % 31) {
374 : 0 : strm->msg = (char *)"incorrect header check";
375 : 0 : state->mode = BAD;
376 : 0 : break;
377 : : }
378 [ # # ]: 0 : if (BITS(4) != Z_DEFLATED) {
379 : 0 : strm->msg = (char *)"unknown compression method";
380 : 0 : state->mode = BAD;
381 : 0 : break;
382 : : }
383 : 0 : DROPBITS(4);
384 : 0 : len = BITS(4) + 8;
385 [ # # ]: 0 : if (len > state->wbits) {
386 : 0 : strm->msg = (char *)"invalid window size";
387 : 0 : state->mode = BAD;
388 : 0 : break;
389 : : }
390 : 0 : state->dmax = 1U << len;
391 : 0 : strm->adler = state->check = zlib_adler32(0L, NULL, 0);
392 [ # # ]: 0 : state->mode = hold & 0x200 ? DICTID : TYPE;
393 : : INITBITS();
394 : 0 : break;
395 : : case DICTID:
396 [ # # ][ # # ]: 0 : NEEDBITS(32);
397 : 0 : strm->adler = state->check = REVERSE(hold);
398 : : INITBITS();
399 : 0 : state->mode = DICT;
400 : : case DICT:
401 [ # # ]: 0 : if (state->havedict == 0) {
402 : 0 : RESTORE();
403 : 0 : return Z_NEED_DICT;
404 : : }
405 : 0 : strm->adler = state->check = zlib_adler32(0L, NULL, 0);
406 : 0 : state->mode = TYPE;
407 : : case TYPE:
408 [ # # ]: 0 : if (flush == Z_BLOCK) goto inf_leave;
409 : : case TYPEDO:
410 [ # # ]: 0 : if (state->last) {
411 : 0 : BYTEBITS();
412 : 0 : state->mode = CHECK;
413 : 0 : break;
414 : : }
415 [ # # ][ # # ]: 0 : NEEDBITS(3);
416 : 0 : state->last = BITS(1);
417 : 0 : DROPBITS(1);
418 [ # # # # : 0 : switch (BITS(2)) {
# ]
419 : : case 0: /* stored block */
420 : 0 : state->mode = STORED;
421 : 0 : break;
422 : : case 1: /* fixed block */
423 : : zlib_fixedtables(state);
424 : 0 : state->mode = LEN; /* decode codes */
425 : 0 : break;
426 : : case 2: /* dynamic block */
427 : 0 : state->mode = TABLE;
428 : 0 : break;
429 : : case 3:
430 : 0 : strm->msg = (char *)"invalid block type";
431 : 0 : state->mode = BAD;
432 : : }
433 : 0 : DROPBITS(2);
434 : 0 : break;
435 : : case STORED:
436 : 0 : BYTEBITS(); /* go to byte boundary */
437 [ # # ][ # # ]: 0 : NEEDBITS(32);
438 [ # # ]: 0 : if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) {
439 : 0 : strm->msg = (char *)"invalid stored block lengths";
440 : 0 : state->mode = BAD;
441 : 0 : break;
442 : : }
443 : 0 : state->length = (unsigned)hold & 0xffff;
444 : : INITBITS();
445 : 0 : state->mode = COPY;
446 : : case COPY:
447 : 0 : copy = state->length;
448 [ # # ]: 0 : if (copy) {
449 [ # # ]: 0 : if (copy > have) copy = have;
450 [ # # ]: 0 : if (copy > left) copy = left;
451 [ # # ]: 0 : if (copy == 0) goto inf_leave;
452 : 0 : memcpy(put, next, copy);
453 : 0 : have -= copy;
454 : 0 : next += copy;
455 : 0 : left -= copy;
456 : 0 : put += copy;
457 : 0 : state->length -= copy;
458 : 0 : break;
459 : : }
460 : 0 : state->mode = TYPE;
461 : 0 : break;
462 : : case TABLE:
463 [ # # ][ # # ]: 0 : NEEDBITS(14);
464 : 0 : state->nlen = BITS(5) + 257;
465 : 0 : DROPBITS(5);
466 : 0 : state->ndist = BITS(5) + 1;
467 : 0 : DROPBITS(5);
468 : 0 : state->ncode = BITS(4) + 4;
469 : 0 : DROPBITS(4);
470 : : #ifndef PKZIP_BUG_WORKAROUND
471 [ # # ][ # # ]: 0 : if (state->nlen > 286 || state->ndist > 30) {
472 : 0 : strm->msg = (char *)"too many length or distance symbols";
473 : 0 : state->mode = BAD;
474 : 0 : break;
475 : : }
476 : : #endif
477 : 0 : state->have = 0;
478 : 0 : state->mode = LENLENS;
479 : : case LENLENS:
480 [ # # ]: 0 : while (state->have < state->ncode) {
481 [ # # ][ # # ]: 0 : NEEDBITS(3);
482 : 0 : state->lens[order[state->have++]] = (unsigned short)BITS(3);
483 : 0 : DROPBITS(3);
484 : : }
485 [ # # ]: 0 : while (state->have < 19)
486 : 0 : state->lens[order[state->have++]] = 0;
487 : 0 : state->next = state->codes;
488 : 0 : state->lencode = (code const *)(state->next);
489 : 0 : state->lenbits = 7;
490 : 0 : ret = zlib_inflate_table(CODES, state->lens, 19, &(state->next),
491 : 0 : &(state->lenbits), state->work);
492 [ # # ]: 0 : if (ret) {
493 : 0 : strm->msg = (char *)"invalid code lengths set";
494 : 0 : state->mode = BAD;
495 : 0 : break;
496 : : }
497 : 0 : state->have = 0;
498 : 0 : state->mode = CODELENS;
499 : : case CODELENS:
500 [ # # ]: 0 : while (state->have < state->nlen + state->ndist) {
501 : : for (;;) {
502 : 0 : this = state->lencode[BITS(state->lenbits)];
503 [ # # ]: 0 : if ((unsigned)(this.bits) <= bits) break;
504 [ # # ]: 0 : PULLBYTE();
505 : 0 : }
506 [ # # ]: 0 : if (this.val < 16) {
507 [ # # ][ # # ]: 0 : NEEDBITS(this.bits);
508 : 0 : DROPBITS(this.bits);
509 : 0 : state->lens[state->have++] = this.val;
510 : : }
511 : : else {
512 [ # # ]: 0 : if (this.val == 16) {
513 [ # # ][ # # ]: 0 : NEEDBITS(this.bits + 2);
514 : 0 : DROPBITS(this.bits);
515 [ # # ]: 0 : if (state->have == 0) {
516 : 0 : strm->msg = (char *)"invalid bit length repeat";
517 : 0 : state->mode = BAD;
518 : 0 : break;
519 : : }
520 : 0 : len = state->lens[state->have - 1];
521 : 0 : copy = 3 + BITS(2);
522 : 0 : DROPBITS(2);
523 : : }
524 [ # # ]: 0 : else if (this.val == 17) {
525 [ # # ][ # # ]: 0 : NEEDBITS(this.bits + 3);
526 : 0 : DROPBITS(this.bits);
527 : : len = 0;
528 : 0 : copy = 3 + BITS(3);
529 : 0 : DROPBITS(3);
530 : : }
531 : : else {
532 [ # # ][ # # ]: 0 : NEEDBITS(this.bits + 7);
533 : 0 : DROPBITS(this.bits);
534 : : len = 0;
535 : 0 : copy = 11 + BITS(7);
536 : 0 : DROPBITS(7);
537 : : }
538 [ # # ]: 0 : if (state->have + copy > state->nlen + state->ndist) {
539 : 0 : strm->msg = (char *)"invalid bit length repeat";
540 : 0 : state->mode = BAD;
541 : 0 : break;
542 : : }
543 [ # # ]: 0 : while (copy--)
544 : 0 : state->lens[state->have++] = (unsigned short)len;
545 : : }
546 : : }
547 : :
548 : : /* handle error breaks in while */
549 [ # # ]: 0 : if (state->mode == BAD) break;
550 : :
551 : : /* build code tables */
552 : 0 : state->next = state->codes;
553 : 0 : state->lencode = (code const *)(state->next);
554 : 0 : state->lenbits = 9;
555 : 0 : ret = zlib_inflate_table(LENS, state->lens, state->nlen, &(state->next),
556 : 0 : &(state->lenbits), state->work);
557 [ # # ]: 0 : if (ret) {
558 : 0 : strm->msg = (char *)"invalid literal/lengths set";
559 : 0 : state->mode = BAD;
560 : 0 : break;
561 : : }
562 : 0 : state->distcode = (code const *)(state->next);
563 : 0 : state->distbits = 6;
564 : 0 : ret = zlib_inflate_table(DISTS, state->lens + state->nlen, state->ndist,
565 : : &(state->next), &(state->distbits), state->work);
566 [ # # ]: 0 : if (ret) {
567 : 0 : strm->msg = (char *)"invalid distances set";
568 : 0 : state->mode = BAD;
569 : 0 : break;
570 : : }
571 : 0 : state->mode = LEN;
572 : : case LEN:
573 [ # # ]: 0 : if (have >= 6 && left >= 258) {
574 : 0 : RESTORE();
575 : 0 : inflate_fast(strm, out);
576 : 0 : LOAD();
577 : 0 : break;
578 : : }
579 : : for (;;) {
580 : 0 : this = state->lencode[BITS(state->lenbits)];
581 [ # # ]: 0 : if ((unsigned)(this.bits) <= bits) break;
582 [ # # ]: 0 : PULLBYTE();
583 : 0 : }
584 [ # # ][ # # ]: 0 : if (this.op && (this.op & 0xf0) == 0) {
585 : : last = this;
586 : : for (;;) {
587 : 0 : this = state->lencode[last.val +
588 : 0 : (BITS(last.bits + last.op) >> last.bits)];
589 [ # # ]: 0 : if ((unsigned)(last.bits + this.bits) <= bits) break;
590 [ # # ]: 0 : PULLBYTE();
591 : 0 : }
592 : 0 : DROPBITS(last.bits);
593 : : }
594 : 0 : DROPBITS(this.bits);
595 : 0 : state->length = (unsigned)this.val;
596 [ # # ]: 0 : if ((int)(this.op) == 0) {
597 : 0 : state->mode = LIT;
598 : 0 : break;
599 : : }
600 [ # # ]: 0 : if (this.op & 32) {
601 : 0 : state->mode = TYPE;
602 : 0 : break;
603 : : }
604 [ # # ]: 0 : if (this.op & 64) {
605 : 0 : strm->msg = (char *)"invalid literal/length code";
606 : 0 : state->mode = BAD;
607 : 0 : break;
608 : : }
609 : 0 : state->extra = (unsigned)(this.op) & 15;
610 : 0 : state->mode = LENEXT;
611 : : case LENEXT:
612 [ # # ]: 0 : if (state->extra) {
613 [ # # ][ # # ]: 0 : NEEDBITS(state->extra);
614 : 0 : state->length += BITS(state->extra);
615 : 0 : DROPBITS(state->extra);
616 : : }
617 : 0 : state->mode = DIST;
618 : : case DIST:
619 : : for (;;) {
620 : 0 : this = state->distcode[BITS(state->distbits)];
621 [ # # ]: 0 : if ((unsigned)(this.bits) <= bits) break;
622 [ # # ]: 0 : PULLBYTE();
623 : 0 : }
624 [ # # ]: 0 : if ((this.op & 0xf0) == 0) {
625 : : last = this;
626 : : for (;;) {
627 : 0 : this = state->distcode[last.val +
628 : 0 : (BITS(last.bits + last.op) >> last.bits)];
629 [ # # ]: 0 : if ((unsigned)(last.bits + this.bits) <= bits) break;
630 [ # # ]: 0 : PULLBYTE();
631 : 0 : }
632 : 0 : DROPBITS(last.bits);
633 : : }
634 : 0 : DROPBITS(this.bits);
635 [ # # ]: 0 : if (this.op & 64) {
636 : 0 : strm->msg = (char *)"invalid distance code";
637 : 0 : state->mode = BAD;
638 : 0 : break;
639 : : }
640 : 0 : state->offset = (unsigned)this.val;
641 : 0 : state->extra = (unsigned)(this.op) & 15;
642 : 0 : state->mode = DISTEXT;
643 : : case DISTEXT:
644 [ # # ]: 0 : if (state->extra) {
645 [ # # ][ # # ]: 0 : NEEDBITS(state->extra);
646 : 0 : state->offset += BITS(state->extra);
647 : 0 : DROPBITS(state->extra);
648 : : }
649 : : #ifdef INFLATE_STRICT
650 : : if (state->offset > state->dmax) {
651 : : strm->msg = (char *)"invalid distance too far back";
652 : : state->mode = BAD;
653 : : break;
654 : : }
655 : : #endif
656 [ # # ]: 0 : if (state->offset > state->whave + out - left) {
657 : 0 : strm->msg = (char *)"invalid distance too far back";
658 : 0 : state->mode = BAD;
659 : 0 : break;
660 : : }
661 : 0 : state->mode = MATCH;
662 : : case MATCH:
663 [ # # ]: 0 : if (left == 0) goto inf_leave;
664 : 0 : copy = out - left;
665 [ # # ]: 0 : if (state->offset > copy) { /* copy from window */
666 : 0 : copy = state->offset - copy;
667 [ # # ]: 0 : if (copy > state->write) {
668 : 0 : copy -= state->write;
669 : 0 : from = state->window + (state->wsize - copy);
670 : : }
671 : : else
672 : 0 : from = state->window + (state->write - copy);
673 [ # # ]: 0 : if (copy > state->length) copy = state->length;
674 : : }
675 : : else { /* copy from output */
676 : 0 : from = put - state->offset;
677 : 0 : copy = state->length;
678 : : }
679 [ # # ]: 0 : if (copy > left) copy = left;
680 : 0 : left -= copy;
681 : 0 : state->length -= copy;
682 : : do {
683 : 0 : *put++ = *from++;
684 [ # # ]: 0 : } while (--copy);
685 [ # # ]: 0 : if (state->length == 0) state->mode = LEN;
686 : : break;
687 : : case LIT:
688 [ # # ]: 0 : if (left == 0) goto inf_leave;
689 : 0 : *put++ = (unsigned char)(state->length);
690 : 0 : left--;
691 : 0 : state->mode = LEN;
692 : 0 : break;
693 : : case CHECK:
694 [ # # ]: 0 : if (state->wrap) {
695 [ # # ][ # # ]: 0 : NEEDBITS(32);
696 : 0 : out -= left;
697 : 0 : strm->total_out += out;
698 : 0 : state->total += out;
699 [ # # ]: 0 : if (out)
700 : 0 : strm->adler = state->check =
701 : 0 : UPDATE(state->check, put - out, out);
702 : : out = left;
703 [ # # ]: 0 : if ((
704 : 0 : REVERSE(hold)) != state->check) {
705 : 0 : strm->msg = (char *)"incorrect data check";
706 : 0 : state->mode = BAD;
707 : 0 : break;
708 : : }
709 : : INITBITS();
710 : : }
711 : 0 : state->mode = DONE;
712 : : case DONE:
713 : : ret = Z_STREAM_END;
714 : : goto inf_leave;
715 : : case BAD:
716 : : ret = Z_DATA_ERROR;
717 : : goto inf_leave;
718 : : case MEM:
719 : : return Z_MEM_ERROR;
720 : : case SYNC:
721 : : default:
722 : 0 : return Z_STREAM_ERROR;
723 : : }
724 : :
725 : : /*
726 : : Return from inflate(), updating the total counts and the check value.
727 : : If there was no progress during the inflate() call, return a buffer
728 : : error. Call zlib_updatewindow() to create and/or update the window state.
729 : : */
730 : : inf_leave:
731 : 0 : RESTORE();
732 [ # # ][ # # ]: 0 : if (state->wsize || (state->mode < CHECK && out != strm->avail_out))
[ # # ]
733 : 0 : zlib_updatewindow(strm, out);
734 : :
735 : 0 : in -= strm->avail_in;
736 : 0 : out -= strm->avail_out;
737 : 0 : strm->total_in += in;
738 : 0 : strm->total_out += out;
739 : 0 : state->total += out;
740 [ # # ][ # # ]: 0 : if (state->wrap && out)
741 : 0 : strm->adler = state->check =
742 : 0 : UPDATE(state->check, strm->next_out - out, out);
743 : :
744 [ # # ][ # # ]: 0 : strm->data_type = state->bits + (state->last ? 64 : 0) +
745 : 0 : (state->mode == TYPE ? 128 : 0);
746 : :
747 [ # # ][ # # ]: 0 : if (flush == Z_PACKET_FLUSH && ret == Z_OK &&
748 [ # # ]: 0 : strm->avail_out != 0 && strm->avail_in == 0)
749 : 0 : return zlib_inflateSyncPacket(strm);
750 : :
751 [ # # ][ # # ]: 0 : if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK)
[ # # ]
752 : : ret = Z_BUF_ERROR;
753 : :
754 : 0 : return ret;
755 : : }
756 : :
757 : 0 : int zlib_inflateEnd(z_streamp strm)
758 : : {
759 [ # # ][ # # ]: 0 : if (strm == NULL || strm->state == NULL)
760 : : return Z_STREAM_ERROR;
761 : 0 : return Z_OK;
762 : : }
763 : :
764 : : #if 0
765 : : int zlib_inflateSetDictionary(z_streamp strm, const Byte *dictionary,
766 : : uInt dictLength)
767 : : {
768 : : struct inflate_state *state;
769 : : unsigned long id;
770 : :
771 : : /* check state */
772 : : if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
773 : : state = (struct inflate_state *)strm->state;
774 : : if (state->wrap != 0 && state->mode != DICT)
775 : : return Z_STREAM_ERROR;
776 : :
777 : : /* check for correct dictionary id */
778 : : if (state->mode == DICT) {
779 : : id = zlib_adler32(0L, NULL, 0);
780 : : id = zlib_adler32(id, dictionary, dictLength);
781 : : if (id != state->check)
782 : : return Z_DATA_ERROR;
783 : : }
784 : :
785 : : /* copy dictionary to window */
786 : : zlib_updatewindow(strm, strm->avail_out);
787 : :
788 : : if (dictLength > state->wsize) {
789 : : memcpy(state->window, dictionary + dictLength - state->wsize,
790 : : state->wsize);
791 : : state->whave = state->wsize;
792 : : }
793 : : else {
794 : : memcpy(state->window + state->wsize - dictLength, dictionary,
795 : : dictLength);
796 : : state->whave = dictLength;
797 : : }
798 : : state->havedict = 1;
799 : : return Z_OK;
800 : : }
801 : : #endif
802 : :
803 : : #if 0
804 : : /*
805 : : Search buf[0..len-1] for the pattern: 0, 0, 0xff, 0xff. Return when found
806 : : or when out of input. When called, *have is the number of pattern bytes
807 : : found in order so far, in 0..3. On return *have is updated to the new
808 : : state. If on return *have equals four, then the pattern was found and the
809 : : return value is how many bytes were read including the last byte of the
810 : : pattern. If *have is less than four, then the pattern has not been found
811 : : yet and the return value is len. In the latter case, zlib_syncsearch() can be
812 : : called again with more data and the *have state. *have is initialized to
813 : : zero for the first call.
814 : : */
815 : : static unsigned zlib_syncsearch(unsigned *have, unsigned char *buf,
816 : : unsigned len)
817 : : {
818 : : unsigned got;
819 : : unsigned next;
820 : :
821 : : got = *have;
822 : : next = 0;
823 : : while (next < len && got < 4) {
824 : : if ((int)(buf[next]) == (got < 2 ? 0 : 0xff))
825 : : got++;
826 : : else if (buf[next])
827 : : got = 0;
828 : : else
829 : : got = 4 - got;
830 : : next++;
831 : : }
832 : : *have = got;
833 : : return next;
834 : : }
835 : : #endif
836 : :
837 : : #if 0
838 : : int zlib_inflateSync(z_streamp strm)
839 : : {
840 : : unsigned len; /* number of bytes to look at or looked at */
841 : : unsigned long in, out; /* temporary to save total_in and total_out */
842 : : unsigned char buf[4]; /* to restore bit buffer to byte string */
843 : : struct inflate_state *state;
844 : :
845 : : /* check parameters */
846 : : if (strm == NULL || strm->state == NULL) return Z_STREAM_ERROR;
847 : : state = (struct inflate_state *)strm->state;
848 : : if (strm->avail_in == 0 && state->bits < 8) return Z_BUF_ERROR;
849 : :
850 : : /* if first time, start search in bit buffer */
851 : : if (state->mode != SYNC) {
852 : : state->mode = SYNC;
853 : : state->hold <<= state->bits & 7;
854 : : state->bits -= state->bits & 7;
855 : : len = 0;
856 : : while (state->bits >= 8) {
857 : : buf[len++] = (unsigned char)(state->hold);
858 : : state->hold >>= 8;
859 : : state->bits -= 8;
860 : : }
861 : : state->have = 0;
862 : : zlib_syncsearch(&(state->have), buf, len);
863 : : }
864 : :
865 : : /* search available input */
866 : : len = zlib_syncsearch(&(state->have), strm->next_in, strm->avail_in);
867 : : strm->avail_in -= len;
868 : : strm->next_in += len;
869 : : strm->total_in += len;
870 : :
871 : : /* return no joy or set up to restart inflate() on a new block */
872 : : if (state->have != 4) return Z_DATA_ERROR;
873 : : in = strm->total_in; out = strm->total_out;
874 : : zlib_inflateReset(strm);
875 : : strm->total_in = in; strm->total_out = out;
876 : : state->mode = TYPE;
877 : : return Z_OK;
878 : : }
879 : : #endif
880 : :
881 : : /*
882 : : * This subroutine adds the data at next_in/avail_in to the output history
883 : : * without performing any output. The output buffer must be "caught up";
884 : : * i.e. no pending output but this should always be the case. The state must
885 : : * be waiting on the start of a block (i.e. mode == TYPE or HEAD). On exit,
886 : : * the output will also be caught up, and the checksum will have been updated
887 : : * if need be.
888 : : */
889 : 0 : int zlib_inflateIncomp(z_stream *z)
890 : : {
891 : 0 : struct inflate_state *state = (struct inflate_state *)z->state;
892 : 0 : Byte *saved_no = z->next_out;
893 : 0 : uInt saved_ao = z->avail_out;
894 : :
895 [ # # ]: 0 : if (state->mode != TYPE && state->mode != HEAD)
896 : : return Z_DATA_ERROR;
897 : :
898 : : /* Setup some variables to allow misuse of updateWindow */
899 : 0 : z->avail_out = 0;
900 : 0 : z->next_out = (unsigned char*)z->next_in + z->avail_in;
901 : :
902 : 0 : zlib_updatewindow(z, z->avail_in);
903 : :
904 : : /* Restore saved variables */
905 : 0 : z->avail_out = saved_ao;
906 : 0 : z->next_out = saved_no;
907 : :
908 : 0 : z->adler = state->check =
909 : 0 : UPDATE(state->check, z->next_in, z->avail_in);
910 : :
911 : 0 : z->total_out += z->avail_in;
912 : 0 : z->total_in += z->avail_in;
913 : 0 : z->next_in += z->avail_in;
914 : 0 : state->total += z->avail_in;
915 : 0 : z->avail_in = 0;
916 : :
917 : 0 : return Z_OK;
918 : : }
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