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32#ifdef STATIC
33#define PREBOOT
34#else
35#include <linux/decompress/unlzma.h>
36#include <linux/slab.h>
37#endif
38
39#include <linux/decompress/mm.h>
40
41#define MIN(a, b) (((a) < (b)) ? (a) : (b))
42
43static long long INIT read_int(unsigned char *ptr, int size)
44{
45 int i;
46 long long ret = 0;
47
48 for (i = 0; i < size; i++)
49 ret = (ret << 8) | ptr[size-i-1];
50 return ret;
51}
52
53#define ENDIAN_CONVERT(x) \
54 x = (typeof(x))read_int((unsigned char *)&x, sizeof(x))
55
56
57
58
59
60
61
62
63
64#include <linux/compiler.h>
65
66#define LZMA_IOBUF_SIZE 0x10000
67
68struct rc {
69 int (*fill)(void*, unsigned int);
70 uint8_t *ptr;
71 uint8_t *buffer;
72 uint8_t *buffer_end;
73 int buffer_size;
74 uint32_t code;
75 uint32_t range;
76 uint32_t bound;
77};
78
79
80#define RC_TOP_BITS 24
81#define RC_MOVE_BITS 5
82#define RC_MODEL_TOTAL_BITS 11
83
84
85static int nofill(void *buffer, unsigned int len)
86{
87 return -1;
88}
89
90
91static void INIT rc_read(struct rc *rc)
92{
93 rc->buffer_size = rc->fill((char *)rc->buffer, LZMA_IOBUF_SIZE);
94 if (rc->buffer_size <= 0)
95 error("unexpected EOF");
96 rc->ptr = rc->buffer;
97 rc->buffer_end = rc->buffer + rc->buffer_size;
98}
99
100
101static inline void INIT rc_init(struct rc *rc,
102 int (*fill)(void*, unsigned int),
103 char *buffer, int buffer_size)
104{
105 if (fill)
106 rc->fill = fill;
107 else
108 rc->fill = nofill;
109 rc->buffer = (uint8_t *)buffer;
110 rc->buffer_size = buffer_size;
111 rc->buffer_end = rc->buffer + rc->buffer_size;
112 rc->ptr = rc->buffer;
113
114 rc->code = 0;
115 rc->range = 0xFFFFFFFF;
116}
117
118static inline void INIT rc_init_code(struct rc *rc)
119{
120 int i;
121
122 for (i = 0; i < 5; i++) {
123 if (rc->ptr >= rc->buffer_end)
124 rc_read(rc);
125 rc->code = (rc->code << 8) | *rc->ptr++;
126 }
127}
128
129
130
131static inline void INIT rc_free(struct rc *rc)
132{
133 free(rc->buffer);
134}
135
136
137static void INIT rc_do_normalize(struct rc *rc)
138{
139 if (rc->ptr >= rc->buffer_end)
140 rc_read(rc);
141 rc->range <<= 8;
142 rc->code = (rc->code << 8) | *rc->ptr++;
143}
144static inline void INIT rc_normalize(struct rc *rc)
145{
146 if (rc->range < (1 << RC_TOP_BITS))
147 rc_do_normalize(rc);
148}
149
150
151
152
153
154static inline uint32_t INIT rc_is_bit_0_helper(struct rc *rc, uint16_t *p)
155{
156 rc_normalize(rc);
157 rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
158 return rc->bound;
159}
160static inline int INIT rc_is_bit_0(struct rc *rc, uint16_t *p)
161{
162 uint32_t t = rc_is_bit_0_helper(rc, p);
163 return rc->code < t;
164}
165
166
167static inline void INIT rc_update_bit_0(struct rc *rc, uint16_t *p)
168{
169 rc->range = rc->bound;
170 *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
171}
172static inline void rc_update_bit_1(struct rc *rc, uint16_t *p)
173{
174 rc->range -= rc->bound;
175 rc->code -= rc->bound;
176 *p -= *p >> RC_MOVE_BITS;
177}
178
179
180static int INIT rc_get_bit(struct rc *rc, uint16_t *p, int *symbol)
181{
182 if (rc_is_bit_0(rc, p)) {
183 rc_update_bit_0(rc, p);
184 *symbol *= 2;
185 return 0;
186 } else {
187 rc_update_bit_1(rc, p);
188 *symbol = *symbol * 2 + 1;
189 return 1;
190 }
191}
192
193
194static inline int INIT rc_direct_bit(struct rc *rc)
195{
196 rc_normalize(rc);
197 rc->range >>= 1;
198 if (rc->code >= rc->range) {
199 rc->code -= rc->range;
200 return 1;
201 }
202 return 0;
203}
204
205
206static inline void INIT
207rc_bit_tree_decode(struct rc *rc, uint16_t *p, int num_levels, int *symbol)
208{
209 int i = num_levels;
210
211 *symbol = 1;
212 while (i--)
213 rc_get_bit(rc, p + *symbol, symbol);
214 *symbol -= 1 << num_levels;
215}
216
217
218
219
220
221
222
223
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225
226
227struct lzma_header {
228 uint8_t pos;
229 uint32_t dict_size;
230 uint64_t dst_size;
231} __attribute__ ((packed)) ;
232
233
234#define LZMA_BASE_SIZE 1846
235#define LZMA_LIT_SIZE 768
236
237#define LZMA_NUM_POS_BITS_MAX 4
238
239#define LZMA_LEN_NUM_LOW_BITS 3
240#define LZMA_LEN_NUM_MID_BITS 3
241#define LZMA_LEN_NUM_HIGH_BITS 8
242
243#define LZMA_LEN_CHOICE 0
244#define LZMA_LEN_CHOICE_2 (LZMA_LEN_CHOICE + 1)
245#define LZMA_LEN_LOW (LZMA_LEN_CHOICE_2 + 1)
246#define LZMA_LEN_MID (LZMA_LEN_LOW \
247 + (1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_LOW_BITS)))
248#define LZMA_LEN_HIGH (LZMA_LEN_MID \
249 +(1 << (LZMA_NUM_POS_BITS_MAX + LZMA_LEN_NUM_MID_BITS)))
250#define LZMA_NUM_LEN_PROBS (LZMA_LEN_HIGH + (1 << LZMA_LEN_NUM_HIGH_BITS))
251
252#define LZMA_NUM_STATES 12
253#define LZMA_NUM_LIT_STATES 7
254
255#define LZMA_START_POS_MODEL_INDEX 4
256#define LZMA_END_POS_MODEL_INDEX 14
257#define LZMA_NUM_FULL_DISTANCES (1 << (LZMA_END_POS_MODEL_INDEX >> 1))
258
259#define LZMA_NUM_POS_SLOT_BITS 6
260#define LZMA_NUM_LEN_TO_POS_STATES 4
261
262#define LZMA_NUM_ALIGN_BITS 4
263
264#define LZMA_MATCH_MIN_LEN 2
265
266#define LZMA_IS_MATCH 0
267#define LZMA_IS_REP (LZMA_IS_MATCH + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
268#define LZMA_IS_REP_G0 (LZMA_IS_REP + LZMA_NUM_STATES)
269#define LZMA_IS_REP_G1 (LZMA_IS_REP_G0 + LZMA_NUM_STATES)
270#define LZMA_IS_REP_G2 (LZMA_IS_REP_G1 + LZMA_NUM_STATES)
271#define LZMA_IS_REP_0_LONG (LZMA_IS_REP_G2 + LZMA_NUM_STATES)
272#define LZMA_POS_SLOT (LZMA_IS_REP_0_LONG \
273 + (LZMA_NUM_STATES << LZMA_NUM_POS_BITS_MAX))
274#define LZMA_SPEC_POS (LZMA_POS_SLOT \
275 +(LZMA_NUM_LEN_TO_POS_STATES << LZMA_NUM_POS_SLOT_BITS))
276#define LZMA_ALIGN (LZMA_SPEC_POS \
277 + LZMA_NUM_FULL_DISTANCES - LZMA_END_POS_MODEL_INDEX)
278#define LZMA_LEN_CODER (LZMA_ALIGN + (1 << LZMA_NUM_ALIGN_BITS))
279#define LZMA_REP_LEN_CODER (LZMA_LEN_CODER + LZMA_NUM_LEN_PROBS)
280#define LZMA_LITERAL (LZMA_REP_LEN_CODER + LZMA_NUM_LEN_PROBS)
281
282
283struct writer {
284 uint8_t *buffer;
285 uint8_t previous_byte;
286 size_t buffer_pos;
287 int bufsize;
288 size_t global_pos;
289 int(*flush)(void*, unsigned int);
290 struct lzma_header *header;
291};
292
293struct cstate {
294 int state;
295 uint32_t rep0, rep1, rep2, rep3;
296};
297
298static inline size_t INIT get_pos(struct writer *wr)
299{
300 return
301 wr->global_pos + wr->buffer_pos;
302}
303
304static inline uint8_t INIT peek_old_byte(struct writer *wr,
305 uint32_t offs)
306{
307 if (!wr->flush) {
308 int32_t pos;
309 while (offs > wr->header->dict_size)
310 offs -= wr->header->dict_size;
311 pos = wr->buffer_pos - offs;
312 return wr->buffer[pos];
313 } else {
314 uint32_t pos = wr->buffer_pos - offs;
315 while (pos >= wr->header->dict_size)
316 pos += wr->header->dict_size;
317 return wr->buffer[pos];
318 }
319
320}
321
322static inline void INIT write_byte(struct writer *wr, uint8_t byte)
323{
324 wr->buffer[wr->buffer_pos++] = wr->previous_byte = byte;
325 if (wr->flush && wr->buffer_pos == wr->header->dict_size) {
326 wr->buffer_pos = 0;
327 wr->global_pos += wr->header->dict_size;
328 wr->flush((char *)wr->buffer, wr->header->dict_size);
329 }
330}
331
332
333static inline void INIT copy_byte(struct writer *wr, uint32_t offs)
334{
335 write_byte(wr, peek_old_byte(wr, offs));
336}
337
338static inline void INIT copy_bytes(struct writer *wr,
339 uint32_t rep0, int len)
340{
341 do {
342 copy_byte(wr, rep0);
343 len--;
344 } while (len != 0 && wr->buffer_pos < wr->header->dst_size);
345}
346
347static inline void INIT process_bit0(struct writer *wr, struct rc *rc,
348 struct cstate *cst, uint16_t *p,
349 int pos_state, uint16_t *prob,
350 int lc, uint32_t literal_pos_mask) {
351 int mi = 1;
352 rc_update_bit_0(rc, prob);
353 prob = (p + LZMA_LITERAL +
354 (LZMA_LIT_SIZE
355 * (((get_pos(wr) & literal_pos_mask) << lc)
356 + (wr->previous_byte >> (8 - lc))))
357 );
358
359 if (cst->state >= LZMA_NUM_LIT_STATES) {
360 int match_byte = peek_old_byte(wr, cst->rep0);
361 do {
362 int bit;
363 uint16_t *prob_lit;
364
365 match_byte <<= 1;
366 bit = match_byte & 0x100;
367 prob_lit = prob + 0x100 + bit + mi;
368 if (rc_get_bit(rc, prob_lit, &mi)) {
369 if (!bit)
370 break;
371 } else {
372 if (bit)
373 break;
374 }
375 } while (mi < 0x100);
376 }
377 while (mi < 0x100) {
378 uint16_t *prob_lit = prob + mi;
379 rc_get_bit(rc, prob_lit, &mi);
380 }
381 write_byte(wr, mi);
382 if (cst->state < 4)
383 cst->state = 0;
384 else if (cst->state < 10)
385 cst->state -= 3;
386 else
387 cst->state -= 6;
388}
389
390static inline void INIT process_bit1(struct writer *wr, struct rc *rc,
391 struct cstate *cst, uint16_t *p,
392 int pos_state, uint16_t *prob) {
393 int offset;
394 uint16_t *prob_len;
395 int num_bits;
396 int len;
397
398 rc_update_bit_1(rc, prob);
399 prob = p + LZMA_IS_REP + cst->state;
400 if (rc_is_bit_0(rc, prob)) {
401 rc_update_bit_0(rc, prob);
402 cst->rep3 = cst->rep2;
403 cst->rep2 = cst->rep1;
404 cst->rep1 = cst->rep0;
405 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 0 : 3;
406 prob = p + LZMA_LEN_CODER;
407 } else {
408 rc_update_bit_1(rc, prob);
409 prob = p + LZMA_IS_REP_G0 + cst->state;
410 if (rc_is_bit_0(rc, prob)) {
411 rc_update_bit_0(rc, prob);
412 prob = (p + LZMA_IS_REP_0_LONG
413 + (cst->state <<
414 LZMA_NUM_POS_BITS_MAX) +
415 pos_state);
416 if (rc_is_bit_0(rc, prob)) {
417 rc_update_bit_0(rc, prob);
418
419 cst->state = cst->state < LZMA_NUM_LIT_STATES ?
420 9 : 11;
421 copy_byte(wr, cst->rep0);
422 return;
423 } else {
424 rc_update_bit_1(rc, prob);
425 }
426 } else {
427 uint32_t distance;
428
429 rc_update_bit_1(rc, prob);
430 prob = p + LZMA_IS_REP_G1 + cst->state;
431 if (rc_is_bit_0(rc, prob)) {
432 rc_update_bit_0(rc, prob);
433 distance = cst->rep1;
434 } else {
435 rc_update_bit_1(rc, prob);
436 prob = p + LZMA_IS_REP_G2 + cst->state;
437 if (rc_is_bit_0(rc, prob)) {
438 rc_update_bit_0(rc, prob);
439 distance = cst->rep2;
440 } else {
441 rc_update_bit_1(rc, prob);
442 distance = cst->rep3;
443 cst->rep3 = cst->rep2;
444 }
445 cst->rep2 = cst->rep1;
446 }
447 cst->rep1 = cst->rep0;
448 cst->rep0 = distance;
449 }
450 cst->state = cst->state < LZMA_NUM_LIT_STATES ? 8 : 11;
451 prob = p + LZMA_REP_LEN_CODER;
452 }
453
454 prob_len = prob + LZMA_LEN_CHOICE;
455 if (rc_is_bit_0(rc, prob_len)) {
456 rc_update_bit_0(rc, prob_len);
457 prob_len = (prob + LZMA_LEN_LOW
458 + (pos_state <<
459 LZMA_LEN_NUM_LOW_BITS));
460 offset = 0;
461 num_bits = LZMA_LEN_NUM_LOW_BITS;
462 } else {
463 rc_update_bit_1(rc, prob_len);
464 prob_len = prob + LZMA_LEN_CHOICE_2;
465 if (rc_is_bit_0(rc, prob_len)) {
466 rc_update_bit_0(rc, prob_len);
467 prob_len = (prob + LZMA_LEN_MID
468 + (pos_state <<
469 LZMA_LEN_NUM_MID_BITS));
470 offset = 1 << LZMA_LEN_NUM_LOW_BITS;
471 num_bits = LZMA_LEN_NUM_MID_BITS;
472 } else {
473 rc_update_bit_1(rc, prob_len);
474 prob_len = prob + LZMA_LEN_HIGH;
475 offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
476 + (1 << LZMA_LEN_NUM_MID_BITS));
477 num_bits = LZMA_LEN_NUM_HIGH_BITS;
478 }
479 }
480
481 rc_bit_tree_decode(rc, prob_len, num_bits, &len);
482 len += offset;
483
484 if (cst->state < 4) {
485 int pos_slot;
486
487 cst->state += LZMA_NUM_LIT_STATES;
488 prob =
489 p + LZMA_POS_SLOT +
490 ((len <
491 LZMA_NUM_LEN_TO_POS_STATES ? len :
492 LZMA_NUM_LEN_TO_POS_STATES - 1)
493 << LZMA_NUM_POS_SLOT_BITS);
494 rc_bit_tree_decode(rc, prob,
495 LZMA_NUM_POS_SLOT_BITS,
496 &pos_slot);
497 if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
498 int i, mi;
499 num_bits = (pos_slot >> 1) - 1;
500 cst->rep0 = 2 | (pos_slot & 1);
501 if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
502 cst->rep0 <<= num_bits;
503 prob = p + LZMA_SPEC_POS +
504 cst->rep0 - pos_slot - 1;
505 } else {
506 num_bits -= LZMA_NUM_ALIGN_BITS;
507 while (num_bits--)
508 cst->rep0 = (cst->rep0 << 1) |
509 rc_direct_bit(rc);
510 prob = p + LZMA_ALIGN;
511 cst->rep0 <<= LZMA_NUM_ALIGN_BITS;
512 num_bits = LZMA_NUM_ALIGN_BITS;
513 }
514 i = 1;
515 mi = 1;
516 while (num_bits--) {
517 if (rc_get_bit(rc, prob + mi, &mi))
518 cst->rep0 |= i;
519 i <<= 1;
520 }
521 } else
522 cst->rep0 = pos_slot;
523 if (++(cst->rep0) == 0)
524 return;
525 }
526
527 len += LZMA_MATCH_MIN_LEN;
528
529 copy_bytes(wr, cst->rep0, len);
530}
531
532
533
534STATIC inline int INIT unlzma(unsigned char *buf, int in_len,
535 int(*fill)(void*, unsigned int),
536 int(*flush)(void*, unsigned int),
537 unsigned char *output,
538 int *posp,
539 void(*error_fn)(char *x)
540 )
541{
542 struct lzma_header header;
543 int lc, pb, lp;
544 uint32_t pos_state_mask;
545 uint32_t literal_pos_mask;
546 uint16_t *p;
547 int num_probs;
548 struct rc rc;
549 int i, mi;
550 struct writer wr;
551 struct cstate cst;
552 unsigned char *inbuf;
553 int ret = -1;
554
555 set_error_fn(error_fn);
556
557 if (buf)
558 inbuf = buf;
559 else
560 inbuf = malloc(LZMA_IOBUF_SIZE);
561 if (!inbuf) {
562 error("Could not allocate input bufer");
563 goto exit_0;
564 }
565
566 cst.state = 0;
567 cst.rep0 = cst.rep1 = cst.rep2 = cst.rep3 = 1;
568
569 wr.header = &header;
570 wr.flush = flush;
571 wr.global_pos = 0;
572 wr.previous_byte = 0;
573 wr.buffer_pos = 0;
574
575 rc_init(&rc, fill, inbuf, in_len);
576
577 for (i = 0; i < sizeof(header); i++) {
578 if (rc.ptr >= rc.buffer_end)
579 rc_read(&rc);
580 ((unsigned char *)&header)[i] = *rc.ptr++;
581 }
582
583 if (header.pos >= (9 * 5 * 5))
584 error("bad header");
585
586 mi = 0;
587 lc = header.pos;
588 while (lc >= 9) {
589 mi++;
590 lc -= 9;
591 }
592 pb = 0;
593 lp = mi;
594 while (lp >= 5) {
595 pb++;
596 lp -= 5;
597 }
598 pos_state_mask = (1 << pb) - 1;
599 literal_pos_mask = (1 << lp) - 1;
600
601 ENDIAN_CONVERT(header.dict_size);
602 ENDIAN_CONVERT(header.dst_size);
603
604 if (header.dict_size == 0)
605 header.dict_size = 1;
606
607 if (output)
608 wr.buffer = output;
609 else {
610 wr.bufsize = MIN(header.dst_size, header.dict_size);
611 wr.buffer = large_malloc(wr.bufsize);
612 }
613 if (wr.buffer == NULL)
614 goto exit_1;
615
616 num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
617 p = (uint16_t *) large_malloc(num_probs * sizeof(*p));
618 if (p == 0)
619 goto exit_2;
620 num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
621 for (i = 0; i < num_probs; i++)
622 p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
623
624 rc_init_code(&rc);
625
626 while (get_pos(&wr) < header.dst_size) {
627 int pos_state = get_pos(&wr) & pos_state_mask;
628 uint16_t *prob = p + LZMA_IS_MATCH +
629 (cst.state << LZMA_NUM_POS_BITS_MAX) + pos_state;
630 if (rc_is_bit_0(&rc, prob))
631 process_bit0(&wr, &rc, &cst, p, pos_state, prob,
632 lc, literal_pos_mask);
633 else {
634 process_bit1(&wr, &rc, &cst, p, pos_state, prob);
635 if (cst.rep0 == 0)
636 break;
637 }
638 }
639
640 if (posp)
641 *posp = rc.ptr-rc.buffer;
642 if (wr.flush)
643 wr.flush(wr.buffer, wr.buffer_pos);
644 ret = 0;
645 large_free(p);
646exit_2:
647 if (!output)
648 large_free(wr.buffer);
649exit_1:
650 if (!buf)
651 free(inbuf);
652exit_0:
653 return ret;
654}
655
656#ifdef PREBOOT
657STATIC int INIT decompress(unsigned char *buf, int in_len,
658 int(*fill)(void*, unsigned int),
659 int(*flush)(void*, unsigned int),
660 unsigned char *output,
661 int *posp,
662 void(*error_fn)(char *x)
663 )
664{
665 return unlzma(buf, in_len - 4, fill, flush, output, posp, error_fn);
666}
667#endif
668
