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1/*
2 * LZO1X Compressor from LZO
3 *
4 * Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
5 *
6 * The full LZO package can be found at:
7 * http://www.oberhumer.com/opensource/lzo/
8 *
9 * Changed for Linux kernel use by:
10 * Nitin Gupta <nitingupta910@gmail.com>
11 * Richard Purdie <rpurdie@openedhand.com>
12 */
13
14#include <linux/module.h>
15#include <linux/kernel.h>
16#include <asm/unaligned.h>
17#include <linux/lzo.h>
18#include "lzodefs.h"
19
20static noinline size_t
21lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
22 unsigned char *out, size_t *out_len,
23 size_t ti, void *wrkmem)
24{
25 const unsigned char *ip;
26 unsigned char *op;
27 const unsigned char * const in_end = in + in_len;
28 const unsigned char * const ip_end = in + in_len - 20;
29 const unsigned char *ii;
30 lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;
31
32 op = out;
33 ip = in;
34 ii = ip;
35 ip += ti < 4 ? 4 - ti : 0;
36
37 for (;;) {
38 const unsigned char *m_pos;
39 size_t t, m_len, m_off;
40 u32 dv;
41literal:
42 ip += 1 + ((ip - ii) >> 5);
43next:
44 if (unlikely(ip >= ip_end))
45 break;
46 dv = get_unaligned_le32(ip);
47 t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK;
48 m_pos = in + dict[t];
49 dict[t] = (lzo_dict_t) (ip - in);
50 if (unlikely(dv != get_unaligned_le32(m_pos)))
51 goto literal;
52
53 ii -= ti;
54 ti = 0;
55 t = ip - ii;
56 if (t != 0) {
57 if (t <= 3) {
58 op[-2] |= t;
59 COPY4(op, ii);
60 op += t;
61 } else if (t <= 16) {
62 *op++ = (t - 3);
63 COPY8(op, ii);
64 COPY8(op + 8, ii + 8);
65 op += t;
66 } else {
67 if (t <= 18) {
68 *op++ = (t - 3);
69 } else {
70 size_t tt = t - 18;
71 *op++ = 0;
72 while (unlikely(tt > 255)) {
73 tt -= 255;
74 *op++ = 0;
75 }
76 *op++ = tt;
77 }
78 do {
79 COPY8(op, ii);
80 COPY8(op + 8, ii + 8);
81 op += 16;
82 ii += 16;
83 t -= 16;
84 } while (t >= 16);
85 if (t > 0) do {
86 *op++ = *ii++;
87 } while (--t > 0);
88 }
89 }
90
91 m_len = 4;
92 {
93#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64)
94 u64 v;
95 v = get_unaligned((const u64 *) (ip + m_len)) ^
96 get_unaligned((const u64 *) (m_pos + m_len));
97 if (unlikely(v == 0)) {
98 do {
99 m_len += 8;
100 v = get_unaligned((const u64 *) (ip + m_len)) ^
101 get_unaligned((const u64 *) (m_pos + m_len));
102 if (unlikely(ip + m_len >= ip_end))
103 goto m_len_done;
104 } while (v == 0);
105 }
106# if defined(__LITTLE_ENDIAN)
107 m_len += (unsigned) __builtin_ctzll(v) / 8;
108# elif defined(__BIG_ENDIAN)
109 m_len += (unsigned) __builtin_clzll(v) / 8;
110# else
111# error "missing endian definition"
112# endif
113#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32)
114 u32 v;
115 v = get_unaligned((const u32 *) (ip + m_len)) ^
116 get_unaligned((const u32 *) (m_pos + m_len));
117 if (unlikely(v == 0)) {
118 do {
119 m_len += 4;
120 v = get_unaligned((const u32 *) (ip + m_len)) ^
121 get_unaligned((const u32 *) (m_pos + m_len));
122 if (v != 0)
123 break;
124 m_len += 4;
125 v = get_unaligned((const u32 *) (ip + m_len)) ^
126 get_unaligned((const u32 *) (m_pos + m_len));
127 if (unlikely(ip + m_len >= ip_end))
128 goto m_len_done;
129 } while (v == 0);
130 }
131# if defined(__LITTLE_ENDIAN)
132 m_len += (unsigned) __builtin_ctz(v) / 8;
133# elif defined(__BIG_ENDIAN)
134 m_len += (unsigned) __builtin_clz(v) / 8;
135# else
136# error "missing endian definition"
137# endif
138#else
139 if (unlikely(ip[m_len] == m_pos[m_len])) {
140 do {
141 m_len += 1;
142 if (ip[m_len] != m_pos[m_len])
143 break;
144 m_len += 1;
145 if (ip[m_len] != m_pos[m_len])
146 break;
147 m_len += 1;
148 if (ip[m_len] != m_pos[m_len])
149 break;
150 m_len += 1;
151 if (ip[m_len] != m_pos[m_len])
152 break;
153 m_len += 1;
154 if (ip[m_len] != m_pos[m_len])
155 break;
156 m_len += 1;
157 if (ip[m_len] != m_pos[m_len])
158 break;
159 m_len += 1;
160 if (ip[m_len] != m_pos[m_len])
161 break;
162 m_len += 1;
163 if (unlikely(ip + m_len >= ip_end))
164 goto m_len_done;
165 } while (ip[m_len] == m_pos[m_len]);
166 }
167#endif
168 }
169m_len_done:
170
171 m_off = ip - m_pos;
172 ip += m_len;
173 ii = ip;
174 if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
175 m_off -= 1;
176 *op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2));
177 *op++ = (m_off >> 3);
178 } else if (m_off <= M3_MAX_OFFSET) {
179 m_off -= 1;
180 if (m_len <= M3_MAX_LEN)
181 *op++ = (M3_MARKER | (m_len - 2));
182 else {
183 m_len -= M3_MAX_LEN;
184 *op++ = M3_MARKER | 0;
185 while (unlikely(m_len > 255)) {
186 m_len -= 255;
187 *op++ = 0;
188 }
189 *op++ = (m_len);
190 }
191 *op++ = (m_off << 2);
192 *op++ = (m_off >> 6);
193 } else {
194 m_off -= 0x4000;
195 if (m_len <= M4_MAX_LEN)
196 *op++ = (M4_MARKER | ((m_off >> 11) & 8)
197 | (m_len - 2));
198 else {
199 m_len -= M4_MAX_LEN;
200 *op++ = (M4_MARKER | ((m_off >> 11) & 8));
201 while (unlikely(m_len > 255)) {
202 m_len -= 255;
203 *op++ = 0;
204 }
205 *op++ = (m_len);
206 }
207 *op++ = (m_off << 2);
208 *op++ = (m_off >> 6);
209 }
210 goto next;
211 }
212 *out_len = op - out;
213 return in_end - (ii - ti);
214}
215
216int lzo1x_1_compress(const unsigned char *in, size_t in_len,
217 unsigned char *out, size_t *out_len,
218 void *wrkmem)
219{
220 const unsigned char *ip = in;
221 unsigned char *op = out;
222 size_t l = in_len;
223 size_t t = 0;
224
225 while (l > 20) {
226 size_t ll = l <= (M4_MAX_OFFSET + 1) ? l : (M4_MAX_OFFSET + 1);
227 uintptr_t ll_end = (uintptr_t) ip + ll;
228 if ((ll_end + ((t + ll) >> 5)) <= ll_end)
229 break;
230 BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
231 memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
232 t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem);
233 ip += ll;
234 op += *out_len;
235 l -= ll;
236 }
237 t += l;
238
239 if (t > 0) {
240 const unsigned char *ii = in + in_len - t;
241
242 if (op == out && t <= 238) {
243 *op++ = (17 + t);
244 } else if (t <= 3) {
245 op[-2] |= t;
246 } else if (t <= 18) {
247 *op++ = (t - 3);
248 } else {
249 size_t tt = t - 18;
250 *op++ = 0;
251 while (tt > 255) {
252 tt -= 255;
253 *op++ = 0;
254 }
255 *op++ = tt;
256 }
257 if (t >= 16) do {
258 COPY8(op, ii);
259 COPY8(op + 8, ii + 8);
260 op += 16;
261 ii += 16;
262 t -= 16;
263 } while (t >= 16);
264 if (t > 0) do {
265 *op++ = *ii++;
266 } while (--t > 0);
267 }
268
269 *op++ = M4_MARKER | 1;
270 *op++ = 0;
271 *op++ = 0;
272
273 *out_len = op - out;
274 return LZO_E_OK;
275}
276EXPORT_SYMBOL_GPL(lzo1x_1_compress);
277
278MODULE_LICENSE("GPL");
279MODULE_DESCRIPTION("LZO1X-1 Compressor");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LZO1X Compressor from LZO
4 *
5 * Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
6 *
7 * The full LZO package can be found at:
8 * http://www.oberhumer.com/opensource/lzo/
9 *
10 * Changed for Linux kernel use by:
11 * Nitin Gupta <nitingupta910@gmail.com>
12 * Richard Purdie <rpurdie@openedhand.com>
13 */
14
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/unaligned.h>
18#include <linux/lzo.h>
19#include "lzodefs.h"
20
21static noinline size_t
22lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
23 unsigned char *out, size_t *out_len,
24 size_t ti, void *wrkmem, signed char *state_offset,
25 const unsigned char bitstream_version)
26{
27 const unsigned char *ip;
28 unsigned char *op;
29 const unsigned char * const in_end = in + in_len;
30 const unsigned char * const ip_end = in + in_len - 20;
31 const unsigned char *ii;
32 lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;
33
34 op = out;
35 ip = in;
36 ii = ip;
37 ip += ti < 4 ? 4 - ti : 0;
38
39 for (;;) {
40 const unsigned char *m_pos = NULL;
41 size_t t, m_len, m_off;
42 u32 dv;
43 u32 run_length = 0;
44literal:
45 ip += 1 + ((ip - ii) >> 5);
46next:
47 if (unlikely(ip >= ip_end))
48 break;
49 dv = get_unaligned_le32(ip);
50
51 if (dv == 0 && bitstream_version) {
52 const unsigned char *ir = ip + 4;
53 const unsigned char *limit = min(ip_end, ip + MAX_ZERO_RUN_LENGTH + 1);
54#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && \
55 defined(LZO_FAST_64BIT_MEMORY_ACCESS)
56 u64 dv64;
57
58 for (; (ir + 32) <= limit; ir += 32) {
59 dv64 = get_unaligned((u64 *)ir);
60 dv64 |= get_unaligned((u64 *)ir + 1);
61 dv64 |= get_unaligned((u64 *)ir + 2);
62 dv64 |= get_unaligned((u64 *)ir + 3);
63 if (dv64)
64 break;
65 }
66 for (; (ir + 8) <= limit; ir += 8) {
67 dv64 = get_unaligned((u64 *)ir);
68 if (dv64) {
69# if defined(__LITTLE_ENDIAN)
70 ir += __builtin_ctzll(dv64) >> 3;
71# elif defined(__BIG_ENDIAN)
72 ir += __builtin_clzll(dv64) >> 3;
73# else
74# error "missing endian definition"
75# endif
76 break;
77 }
78 }
79#else
80 while ((ir < (const unsigned char *)
81 ALIGN((uintptr_t)ir, 4)) &&
82 (ir < limit) && (*ir == 0))
83 ir++;
84 if (IS_ALIGNED((uintptr_t)ir, 4)) {
85 for (; (ir + 4) <= limit; ir += 4) {
86 dv = *((u32 *)ir);
87 if (dv) {
88# if defined(__LITTLE_ENDIAN)
89 ir += __builtin_ctz(dv) >> 3;
90# elif defined(__BIG_ENDIAN)
91 ir += __builtin_clz(dv) >> 3;
92# else
93# error "missing endian definition"
94# endif
95 break;
96 }
97 }
98 }
99#endif
100 while (likely(ir < limit) && unlikely(*ir == 0))
101 ir++;
102 run_length = ir - ip;
103 if (run_length > MAX_ZERO_RUN_LENGTH)
104 run_length = MAX_ZERO_RUN_LENGTH;
105 } else {
106 t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK;
107 m_pos = in + dict[t];
108 dict[t] = (lzo_dict_t) (ip - in);
109 if (unlikely(dv != get_unaligned_le32(m_pos)))
110 goto literal;
111 }
112
113 ii -= ti;
114 ti = 0;
115 t = ip - ii;
116 if (t != 0) {
117 if (t <= 3) {
118 op[*state_offset] |= t;
119 COPY4(op, ii);
120 op += t;
121 } else if (t <= 16) {
122 *op++ = (t - 3);
123 COPY8(op, ii);
124 COPY8(op + 8, ii + 8);
125 op += t;
126 } else {
127 if (t <= 18) {
128 *op++ = (t - 3);
129 } else {
130 size_t tt = t - 18;
131 *op++ = 0;
132 while (unlikely(tt > 255)) {
133 tt -= 255;
134 *op++ = 0;
135 }
136 *op++ = tt;
137 }
138 do {
139 COPY8(op, ii);
140 COPY8(op + 8, ii + 8);
141 op += 16;
142 ii += 16;
143 t -= 16;
144 } while (t >= 16);
145 if (t > 0) do {
146 *op++ = *ii++;
147 } while (--t > 0);
148 }
149 }
150
151 if (unlikely(run_length)) {
152 ip += run_length;
153 run_length -= MIN_ZERO_RUN_LENGTH;
154 put_unaligned_le32((run_length << 21) | 0xfffc18
155 | (run_length & 0x7), op);
156 op += 4;
157 run_length = 0;
158 *state_offset = -3;
159 goto finished_writing_instruction;
160 }
161
162 m_len = 4;
163 {
164#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64)
165 u64 v;
166 v = get_unaligned((const u64 *) (ip + m_len)) ^
167 get_unaligned((const u64 *) (m_pos + m_len));
168 if (unlikely(v == 0)) {
169 do {
170 m_len += 8;
171 v = get_unaligned((const u64 *) (ip + m_len)) ^
172 get_unaligned((const u64 *) (m_pos + m_len));
173 if (unlikely(ip + m_len >= ip_end))
174 goto m_len_done;
175 } while (v == 0);
176 }
177# if defined(__LITTLE_ENDIAN)
178 m_len += (unsigned) __builtin_ctzll(v) / 8;
179# elif defined(__BIG_ENDIAN)
180 m_len += (unsigned) __builtin_clzll(v) / 8;
181# else
182# error "missing endian definition"
183# endif
184#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32)
185 u32 v;
186 v = get_unaligned((const u32 *) (ip + m_len)) ^
187 get_unaligned((const u32 *) (m_pos + m_len));
188 if (unlikely(v == 0)) {
189 do {
190 m_len += 4;
191 v = get_unaligned((const u32 *) (ip + m_len)) ^
192 get_unaligned((const u32 *) (m_pos + m_len));
193 if (v != 0)
194 break;
195 m_len += 4;
196 v = get_unaligned((const u32 *) (ip + m_len)) ^
197 get_unaligned((const u32 *) (m_pos + m_len));
198 if (unlikely(ip + m_len >= ip_end))
199 goto m_len_done;
200 } while (v == 0);
201 }
202# if defined(__LITTLE_ENDIAN)
203 m_len += (unsigned) __builtin_ctz(v) / 8;
204# elif defined(__BIG_ENDIAN)
205 m_len += (unsigned) __builtin_clz(v) / 8;
206# else
207# error "missing endian definition"
208# endif
209#else
210 if (unlikely(ip[m_len] == m_pos[m_len])) {
211 do {
212 m_len += 1;
213 if (ip[m_len] != m_pos[m_len])
214 break;
215 m_len += 1;
216 if (ip[m_len] != m_pos[m_len])
217 break;
218 m_len += 1;
219 if (ip[m_len] != m_pos[m_len])
220 break;
221 m_len += 1;
222 if (ip[m_len] != m_pos[m_len])
223 break;
224 m_len += 1;
225 if (ip[m_len] != m_pos[m_len])
226 break;
227 m_len += 1;
228 if (ip[m_len] != m_pos[m_len])
229 break;
230 m_len += 1;
231 if (ip[m_len] != m_pos[m_len])
232 break;
233 m_len += 1;
234 if (unlikely(ip + m_len >= ip_end))
235 goto m_len_done;
236 } while (ip[m_len] == m_pos[m_len]);
237 }
238#endif
239 }
240m_len_done:
241
242 m_off = ip - m_pos;
243 ip += m_len;
244 if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
245 m_off -= 1;
246 *op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2));
247 *op++ = (m_off >> 3);
248 } else if (m_off <= M3_MAX_OFFSET) {
249 m_off -= 1;
250 if (m_len <= M3_MAX_LEN)
251 *op++ = (M3_MARKER | (m_len - 2));
252 else {
253 m_len -= M3_MAX_LEN;
254 *op++ = M3_MARKER | 0;
255 while (unlikely(m_len > 255)) {
256 m_len -= 255;
257 *op++ = 0;
258 }
259 *op++ = (m_len);
260 }
261 *op++ = (m_off << 2);
262 *op++ = (m_off >> 6);
263 } else {
264 m_off -= 0x4000;
265 if (m_len <= M4_MAX_LEN)
266 *op++ = (M4_MARKER | ((m_off >> 11) & 8)
267 | (m_len - 2));
268 else {
269 if (unlikely(((m_off & 0x403f) == 0x403f)
270 && (m_len >= 261)
271 && (m_len <= 264))
272 && likely(bitstream_version)) {
273 // Under lzo-rle, block copies
274 // for 261 <= length <= 264 and
275 // (distance & 0x80f3) == 0x80f3
276 // can result in ambiguous
277 // output. Adjust length
278 // to 260 to prevent ambiguity.
279 ip -= m_len - 260;
280 m_len = 260;
281 }
282 m_len -= M4_MAX_LEN;
283 *op++ = (M4_MARKER | ((m_off >> 11) & 8));
284 while (unlikely(m_len > 255)) {
285 m_len -= 255;
286 *op++ = 0;
287 }
288 *op++ = (m_len);
289 }
290 *op++ = (m_off << 2);
291 *op++ = (m_off >> 6);
292 }
293 *state_offset = -2;
294finished_writing_instruction:
295 ii = ip;
296 goto next;
297 }
298 *out_len = op - out;
299 return in_end - (ii - ti);
300}
301
302static int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
303 unsigned char *out, size_t *out_len,
304 void *wrkmem, const unsigned char bitstream_version)
305{
306 const unsigned char *ip = in;
307 unsigned char *op = out;
308 unsigned char *data_start;
309 size_t l = in_len;
310 size_t t = 0;
311 signed char state_offset = -2;
312 unsigned int m4_max_offset;
313
314 // LZO v0 will never write 17 as first byte (except for zero-length
315 // input), so this is used to version the bitstream
316 if (bitstream_version > 0) {
317 *op++ = 17;
318 *op++ = bitstream_version;
319 m4_max_offset = M4_MAX_OFFSET_V1;
320 } else {
321 m4_max_offset = M4_MAX_OFFSET_V0;
322 }
323
324 data_start = op;
325
326 while (l > 20) {
327 size_t ll = min_t(size_t, l, m4_max_offset + 1);
328 uintptr_t ll_end = (uintptr_t) ip + ll;
329 if ((ll_end + ((t + ll) >> 5)) <= ll_end)
330 break;
331 BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
332 memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
333 t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem,
334 &state_offset, bitstream_version);
335 ip += ll;
336 op += *out_len;
337 l -= ll;
338 }
339 t += l;
340
341 if (t > 0) {
342 const unsigned char *ii = in + in_len - t;
343
344 if (op == data_start && t <= 238) {
345 *op++ = (17 + t);
346 } else if (t <= 3) {
347 op[state_offset] |= t;
348 } else if (t <= 18) {
349 *op++ = (t - 3);
350 } else {
351 size_t tt = t - 18;
352 *op++ = 0;
353 while (tt > 255) {
354 tt -= 255;
355 *op++ = 0;
356 }
357 *op++ = tt;
358 }
359 if (t >= 16) do {
360 COPY8(op, ii);
361 COPY8(op + 8, ii + 8);
362 op += 16;
363 ii += 16;
364 t -= 16;
365 } while (t >= 16);
366 if (t > 0) do {
367 *op++ = *ii++;
368 } while (--t > 0);
369 }
370
371 *op++ = M4_MARKER | 1;
372 *op++ = 0;
373 *op++ = 0;
374
375 *out_len = op - out;
376 return LZO_E_OK;
377}
378
379int lzo1x_1_compress(const unsigned char *in, size_t in_len,
380 unsigned char *out, size_t *out_len,
381 void *wrkmem)
382{
383 return lzogeneric1x_1_compress(in, in_len, out, out_len, wrkmem, 0);
384}
385
386int lzorle1x_1_compress(const unsigned char *in, size_t in_len,
387 unsigned char *out, size_t *out_len,
388 void *wrkmem)
389{
390 return lzogeneric1x_1_compress(in, in_len, out, out_len,
391 wrkmem, LZO_VERSION);
392}
393
394EXPORT_SYMBOL_GPL(lzo1x_1_compress);
395EXPORT_SYMBOL_GPL(lzorle1x_1_compress);
396
397MODULE_LICENSE("GPL");
398MODULE_DESCRIPTION("LZO1X-1 Compressor");