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26#include "libbb.h"
27#include "liblzo.h"
28
29
30
31
32
33int lzo1x_decompress_safe(const uint8_t* in, unsigned in_len,
34 uint8_t* out, unsigned* out_len,
35 void* wrkmem UNUSED_PARAM)
36{
37 register uint8_t* op;
38 register const uint8_t* ip;
39 register unsigned t;
40#if defined(COPY_DICT)
41 unsigned m_off;
42 const uint8_t* dict_end;
43#else
44 register const uint8_t* m_pos = NULL;
45#endif
46 const uint8_t* const ip_end = in + in_len;
47#if defined(HAVE_ANY_OP)
48 uint8_t* const op_end = out + *out_len;
49#endif
50#if defined(LZO1Z)
51 unsigned last_m_off = 0;
52#endif
53
54
55
56#if defined(COPY_DICT)
57 if (dict) {
58 if (dict_len > M4_MAX_OFFSET) {
59 dict += dict_len - M4_MAX_OFFSET;
60 dict_len = M4_MAX_OFFSET;
61 }
62 dict_end = dict + dict_len;
63 } else {
64 dict_len = 0;
65 dict_end = NULL;
66 }
67#endif
68
69 *out_len = 0;
70
71 op = out;
72 ip = in;
73
74 if (*ip > 17) {
75 t = *ip++ - 17;
76 if (t < 4)
77 goto match_next;
78 assert(t > 0); NEED_OP(t); NEED_IP(t+1);
79 do *op++ = *ip++; while (--t > 0);
80 goto first_literal_run;
81 }
82
83 while (TEST_IP && TEST_OP) {
84 t = *ip++;
85 if (t >= 16)
86 goto match;
87
88 if (t == 0) {
89 NEED_IP(1);
90 while (*ip == 0) {
91 t += 255;
92 ip++;
93 NEED_IP(1);
94 }
95 TEST_IV(t);
96 t += 15 + *ip++;
97 }
98
99 assert(t > 0);
100 NEED_OP(t+3);
101 NEED_IP(t+4);
102#if defined(LZO_UNALIGNED_OK_4) || defined(LZO_ALIGNED_OK_4)
103# if !defined(LZO_UNALIGNED_OK_4)
104 if (PTR_ALIGNED2_4(op, ip))
105# endif
106 {
107 COPY4(op, ip);
108 op += 4;
109 ip += 4;
110 if (--t > 0) {
111 if (t >= 4) {
112 do {
113 COPY4(op, ip);
114 op += 4;
115 ip += 4;
116 t -= 4;
117 } while (t >= 4);
118 if (t > 0)
119 do *op++ = *ip++; while (--t > 0);
120 } else {
121 do *op++ = *ip++; while (--t > 0);
122 }
123 }
124 }
125# if !defined(LZO_UNALIGNED_OK_4)
126 else
127# endif
128#endif
129#if !defined(LZO_UNALIGNED_OK_4)
130 {
131 *op++ = *ip++;
132 *op++ = *ip++;
133 *op++ = *ip++;
134 do *op++ = *ip++; while (--t > 0);
135 }
136#endif
137
138 first_literal_run:
139 t = *ip++;
140 if (t >= 16)
141 goto match;
142#if defined(COPY_DICT)
143#if defined(LZO1Z)
144 m_off = (1 + M2_MAX_OFFSET) + (t << 6) + (*ip++ >> 2);
145 last_m_off = m_off;
146#else
147 m_off = (1 + M2_MAX_OFFSET) + (t >> 2) + (*ip++ << 2);
148#endif
149 NEED_OP(3);
150 t = 3; COPY_DICT(t,m_off)
151#else
152#if defined(LZO1Z)
153 t = (1 + M2_MAX_OFFSET) + (t << 6) + (*ip++ >> 2);
154 m_pos = op - t;
155 last_m_off = t;
156#else
157 m_pos = op - (1 + M2_MAX_OFFSET);
158 m_pos -= t >> 2;
159 m_pos -= *ip++ << 2;
160#endif
161 TEST_LB(m_pos); NEED_OP(3);
162 *op++ = *m_pos++;
163 *op++ = *m_pos++;
164 *op++ = *m_pos;
165#endif
166 goto match_done;
167
168
169 do {
170 match:
171 if (t >= 64) {
172#if defined(COPY_DICT)
173#if defined(LZO1X)
174 m_off = 1 + ((t >> 2) & 7) + (*ip++ << 3);
175 t = (t >> 5) - 1;
176#elif defined(LZO1Y)
177 m_off = 1 + ((t >> 2) & 3) + (*ip++ << 2);
178 t = (t >> 4) - 3;
179#elif defined(LZO1Z)
180 m_off = t & 0x1f;
181 if (m_off >= 0x1c)
182 m_off = last_m_off;
183 else {
184 m_off = 1 + (m_off << 6) + (*ip++ >> 2);
185 last_m_off = m_off;
186 }
187 t = (t >> 5) - 1;
188#endif
189#else
190#if defined(LZO1X)
191 m_pos = op - 1;
192 m_pos -= (t >> 2) & 7;
193 m_pos -= *ip++ << 3;
194 t = (t >> 5) - 1;
195#elif defined(LZO1Y)
196 m_pos = op - 1;
197 m_pos -= (t >> 2) & 3;
198 m_pos -= *ip++ << 2;
199 t = (t >> 4) - 3;
200#elif defined(LZO1Z)
201 {
202 unsigned off = t & 0x1f;
203 m_pos = op;
204 if (off >= 0x1c) {
205 assert(last_m_off > 0);
206 m_pos -= last_m_off;
207 } else {
208 off = 1 + (off << 6) + (*ip++ >> 2);
209 m_pos -= off;
210 last_m_off = off;
211 }
212 }
213 t = (t >> 5) - 1;
214#endif
215 TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
216 goto copy_match;
217#endif
218 }
219 else if (t >= 32) {
220 t &= 31;
221 if (t == 0) {
222 NEED_IP(1);
223 while (*ip == 0) {
224 t += 255;
225 ip++;
226 NEED_IP(1);
227 }
228 TEST_IV(t);
229 t += 31 + *ip++;
230 }
231#if defined(COPY_DICT)
232#if defined(LZO1Z)
233 m_off = 1 + (ip[0] << 6) + (ip[1] >> 2);
234 last_m_off = m_off;
235#else
236 m_off = 1 + (ip[0] >> 2) + (ip[1] << 6);
237#endif
238#else
239#if defined(LZO1Z)
240 {
241 unsigned off = 1 + (ip[0] << 6) + (ip[1] >> 2);
242 m_pos = op - off;
243 last_m_off = off;
244 }
245#elif defined(LZO_UNALIGNED_OK_2) && defined(LZO_ABI_LITTLE_ENDIAN)
246 m_pos = op - 1;
247 m_pos -= (* (const lzo_ushortp) ip) >> 2;
248#else
249 m_pos = op - 1;
250 m_pos -= (ip[0] >> 2) + (ip[1] << 6);
251#endif
252#endif
253 ip += 2;
254 }
255 else if (t >= 16) {
256#if defined(COPY_DICT)
257 m_off = (t & 8) << 11;
258#else
259 m_pos = op;
260 m_pos -= (t & 8) << 11;
261#endif
262 t &= 7;
263 if (t == 0) {
264 NEED_IP(1);
265 while (*ip == 0) {
266 t += 255;
267 ip++;
268 NEED_IP(1);
269 }
270 TEST_IV(t);
271 t += 7 + *ip++;
272 }
273#if defined(COPY_DICT)
274#if defined(LZO1Z)
275 m_off += (ip[0] << 6) + (ip[1] >> 2);
276#else
277 m_off += (ip[0] >> 2) + (ip[1] << 6);
278#endif
279 ip += 2;
280 if (m_off == 0)
281 goto eof_found;
282 m_off += 0x4000;
283#if defined(LZO1Z)
284 last_m_off = m_off;
285#endif
286#else
287#if defined(LZO1Z)
288 m_pos -= (ip[0] << 6) + (ip[1] >> 2);
289#elif defined(LZO_UNALIGNED_OK_2) && defined(LZO_ABI_LITTLE_ENDIAN)
290 m_pos -= (* (const lzo_ushortp) ip) >> 2;
291#else
292 m_pos -= (ip[0] >> 2) + (ip[1] << 6);
293#endif
294 ip += 2;
295 if (m_pos == op)
296 goto eof_found;
297 m_pos -= 0x4000;
298#if defined(LZO1Z)
299 last_m_off = pd((const uint8_t*)op, m_pos);
300#endif
301#endif
302 }
303 else {
304#if defined(COPY_DICT)
305#if defined(LZO1Z)
306 m_off = 1 + (t << 6) + (*ip++ >> 2);
307 last_m_off = m_off;
308#else
309 m_off = 1 + (t >> 2) + (*ip++ << 2);
310#endif
311 NEED_OP(2);
312 t = 2; COPY_DICT(t,m_off)
313#else
314#if defined(LZO1Z)
315 t = 1 + (t << 6) + (*ip++ >> 2);
316 m_pos = op - t;
317 last_m_off = t;
318#else
319 m_pos = op - 1;
320 m_pos -= t >> 2;
321 m_pos -= *ip++ << 2;
322#endif
323 TEST_LB(m_pos); NEED_OP(2);
324 *op++ = *m_pos++;
325 *op++ = *m_pos;
326#endif
327 goto match_done;
328 }
329
330
331#if defined(COPY_DICT)
332
333 NEED_OP(t+3-1);
334 t += 3-1; COPY_DICT(t,m_off)
335
336#else
337
338 TEST_LB(m_pos); assert(t > 0); NEED_OP(t+3-1);
339#if defined(LZO_UNALIGNED_OK_4) || defined(LZO_ALIGNED_OK_4)
340# if !defined(LZO_UNALIGNED_OK_4)
341 if (t >= 2 * 4 - (3 - 1) && PTR_ALIGNED2_4(op,m_pos)) {
342 assert((op - m_pos) >= 4);
343# else
344 if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4) {
345# endif
346 COPY4(op,m_pos);
347 op += 4; m_pos += 4; t -= 4 - (3 - 1);
348 do {
349 COPY4(op,m_pos);
350 op += 4; m_pos += 4; t -= 4;
351 } while (t >= 4);
352 if (t > 0)
353 do *op++ = *m_pos++; while (--t > 0);
354 }
355 else
356#endif
357 {
358 copy_match:
359 *op++ = *m_pos++; *op++ = *m_pos++;
360 do *op++ = *m_pos++; while (--t > 0);
361 }
362
363#endif
364
365 match_done:
366#if defined(LZO1Z)
367 t = ip[-1] & 3;
368#else
369 t = ip[-2] & 3;
370#endif
371 if (t == 0)
372 break;
373
374
375 match_next:
376 assert(t > 0);
377 assert(t < 4);
378 NEED_OP(t);
379 NEED_IP(t+1);
380#if 0
381 do *op++ = *ip++; while (--t > 0);
382#else
383 *op++ = *ip++;
384 if (t > 1) {
385 *op++ = *ip++;
386 if (t > 2)
387 *op++ = *ip++;
388 }
389#endif
390 t = *ip++;
391 } while (TEST_IP && TEST_OP);
392 }
393
394
395
396 *out_len = pd(op, out);
397 return LZO_E_EOF_NOT_FOUND;
398
399
400 eof_found:
401 assert(t == 1);
402 *out_len = pd(op, out);
403 return (ip == ip_end ? LZO_E_OK :
404 (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN));
405
406
407 input_overrun:
408 *out_len = pd(op, out);
409 return LZO_E_INPUT_OVERRUN;
410
411
412
413 output_overrun:
414 *out_len = pd(op, out);
415 return LZO_E_OUTPUT_OVERRUN;
416
417
418
419 lookbehind_overrun:
420 *out_len = pd(op, out);
421 return LZO_E_LOOKBEHIND_OVERRUN;
422
423}
424
