1 /*-
2 * Copyright (c) 2003-2007 Tim Kientzle
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "archive_platform.h"
27
28 __FBSDID("$FreeBSD$");
29
30 #ifdef HAVE_ERRNO_H
31 #include <errno.h>
32 #endif
33 #include <stdio.h>
34 #ifdef HAVE_STDLIB_H
35 #include <stdlib.h>
36 #endif
37 #ifdef HAVE_STRING_H
38 #include <string.h>
39 #endif
40 #ifdef HAVE_UNISTD_H
41 #include <unistd.h>
42 #endif
43 #ifdef HAVE_BZLIB_H
44 #include <bzlib.h>
45 #endif
46
47 #include "archive.h"
48 #include "archive_private.h"
49 #include "archive_read_private.h"
50
51 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR)
52 struct private_data {
53 bz_stream stream;
54 char *out_block;
55 size_t out_block_size;
56 char valid; /* True = decompressor is initialized */
57 char eof; /* True = found end of compressed data. */
58 };
59
60 /* Bzip2 filter */
61 static ssize_t bzip2_filter_read(struct archive_read_filter *, const void **);
62 static int bzip2_filter_close(struct archive_read_filter *);
63 #endif
64
65 /*
66 * Note that we can detect bzip2 archives even if we can't decompress
67 * them. (In fact, we like detecting them because we can give better
68 * error messages.) So the bid framework here gets compiled even
69 * if bzlib is unavailable.
70 */
71 static int bzip2_reader_bid(struct archive_read_filter_bidder *, struct archive_read_filter *);
72 static int bzip2_reader_init(struct archive_read_filter *);
73
74 #if ARCHIVE_VERSION_NUMBER < 4000000
75 /* Deprecated; remove in libarchive 4.0 */
76 int
archive_read_support_compression_bzip2(struct archive * a)77 archive_read_support_compression_bzip2(struct archive *a)
78 {
79 return archive_read_support_filter_bzip2(a);
80 }
81 #endif
82
83 static const struct archive_read_filter_bidder_vtable
84 bzip2_bidder_vtable = {
85 .bid = bzip2_reader_bid,
86 .init = bzip2_reader_init,
87 };
88
89 int
archive_read_support_filter_bzip2(struct archive * _a)90 archive_read_support_filter_bzip2(struct archive *_a)
91 {
92 struct archive_read *a = (struct archive_read *)_a;
93
94 if (__archive_read_register_bidder(a, NULL, "bzip2",
95 &bzip2_bidder_vtable) != ARCHIVE_OK)
96 return (ARCHIVE_FATAL);
97
98 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR)
99 return (ARCHIVE_OK);
100 #else
101 archive_set_error(_a, ARCHIVE_ERRNO_MISC,
102 "Using external bzip2 program");
103 return (ARCHIVE_WARN);
104 #endif
105 }
106
107 /*
108 * Test whether we can handle this data.
109 *
110 * This logic returns zero if any part of the signature fails. It
111 * also tries to Do The Right Thing if a very short buffer prevents us
112 * from verifying as much as we would like.
113 */
114 static int
bzip2_reader_bid(struct archive_read_filter_bidder * self,struct archive_read_filter * filter)115 bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter)
116 {
117 const unsigned char *buffer;
118 ssize_t avail;
119 int bits_checked;
120
121 (void)self; /* UNUSED */
122
123 /* Minimal bzip2 archive is 14 bytes. */
124 buffer = __archive_read_filter_ahead(filter, 14, &avail);
125 if (buffer == NULL)
126 return (0);
127
128 /* First three bytes must be "BZh" */
129 bits_checked = 0;
130 if (memcmp(buffer, "BZh", 3) != 0)
131 return (0);
132 bits_checked += 24;
133
134 /* Next follows a compression flag which must be an ASCII digit. */
135 if (buffer[3] < '1' || buffer[3] > '9')
136 return (0);
137 bits_checked += 5;
138
139 /* After BZh[1-9], there must be either a data block
140 * which begins with 0x314159265359 or an end-of-data
141 * marker of 0x177245385090. */
142 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0)
143 bits_checked += 48;
144 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0)
145 bits_checked += 48;
146 else
147 return (0);
148
149 return (bits_checked);
150 }
151
152 #if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR)
153
154 /*
155 * If we don't have the library on this system, we can't actually do the
156 * decompression. We can, however, still detect compressed archives
157 * and emit a useful message.
158 */
159 static int
bzip2_reader_init(struct archive_read_filter * self)160 bzip2_reader_init(struct archive_read_filter *self)
161 {
162 int r;
163
164 r = __archive_read_program(self, "bzip2 -d");
165 /* Note: We set the format here even if __archive_read_program()
166 * above fails. We do, after all, know what the format is
167 * even if we weren't able to read it. */
168 self->code = ARCHIVE_FILTER_BZIP2;
169 self->name = "bzip2";
170 return (r);
171 }
172
173
174 #else
175
176 static const struct archive_read_filter_vtable
177 bzip2_reader_vtable = {
178 .read = bzip2_filter_read,
179 .close = bzip2_filter_close,
180 };
181
182 /*
183 * Setup the callbacks.
184 */
185 static int
bzip2_reader_init(struct archive_read_filter * self)186 bzip2_reader_init(struct archive_read_filter *self)
187 {
188 static const size_t out_block_size = 64 * 1024;
189 void *out_block;
190 struct private_data *state;
191
192 self->code = ARCHIVE_FILTER_BZIP2;
193 self->name = "bzip2";
194
195 state = (struct private_data *)calloc(sizeof(*state), 1);
196 out_block = (unsigned char *)malloc(out_block_size);
197 if (state == NULL || out_block == NULL) {
198 archive_set_error(&self->archive->archive, ENOMEM,
199 "Can't allocate data for bzip2 decompression");
200 free(out_block);
201 free(state);
202 return (ARCHIVE_FATAL);
203 }
204
205 self->data = state;
206 state->out_block_size = out_block_size;
207 state->out_block = out_block;
208 self->vtable = &bzip2_reader_vtable;
209
210 return (ARCHIVE_OK);
211 }
212
213 /*
214 * Return the next block of decompressed data.
215 */
216 static ssize_t
bzip2_filter_read(struct archive_read_filter * self,const void ** p)217 bzip2_filter_read(struct archive_read_filter *self, const void **p)
218 {
219 struct private_data *state;
220 size_t decompressed;
221 const char *read_buf;
222 ssize_t ret;
223
224 state = (struct private_data *)self->data;
225
226 if (state->eof) {
227 *p = NULL;
228 return (0);
229 }
230
231 /* Empty our output buffer. */
232 state->stream.next_out = state->out_block;
233 state->stream.avail_out = state->out_block_size;
234
235 /* Try to fill the output buffer. */
236 for (;;) {
237 if (!state->valid) {
238 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) {
239 state->eof = 1;
240 *p = state->out_block;
241 decompressed = state->stream.next_out
242 - state->out_block;
243 return (decompressed);
244 }
245 /* Initialize compression library. */
246 ret = BZ2_bzDecompressInit(&(state->stream),
247 0 /* library verbosity */,
248 0 /* don't use low-mem algorithm */);
249
250 /* If init fails, try low-memory algorithm instead. */
251 if (ret == BZ_MEM_ERROR)
252 ret = BZ2_bzDecompressInit(&(state->stream),
253 0 /* library verbosity */,
254 1 /* do use low-mem algo */);
255
256 if (ret != BZ_OK) {
257 const char *detail = NULL;
258 int err = ARCHIVE_ERRNO_MISC;
259 switch (ret) {
260 case BZ_PARAM_ERROR:
261 detail = "invalid setup parameter";
262 break;
263 case BZ_MEM_ERROR:
264 err = ENOMEM;
265 detail = "out of memory";
266 break;
267 case BZ_CONFIG_ERROR:
268 detail = "mis-compiled library";
269 break;
270 }
271 archive_set_error(&self->archive->archive, err,
272 "Internal error initializing decompressor%s%s",
273 detail == NULL ? "" : ": ",
274 detail);
275 return (ARCHIVE_FATAL);
276 }
277 state->valid = 1;
278 }
279
280 /* stream.next_in is really const, but bzlib
281 * doesn't declare it so. <sigh> */
282 read_buf =
283 __archive_read_filter_ahead(self->upstream, 1, &ret);
284 if (read_buf == NULL) {
285 archive_set_error(&self->archive->archive,
286 ARCHIVE_ERRNO_MISC,
287 "truncated bzip2 input");
288 return (ARCHIVE_FATAL);
289 }
290 state->stream.next_in = (char *)(uintptr_t)read_buf;
291 state->stream.avail_in = ret;
292 /* There is no more data, return whatever we have. */
293 if (ret == 0) {
294 state->eof = 1;
295 *p = state->out_block;
296 decompressed = state->stream.next_out
297 - state->out_block;
298 return (decompressed);
299 }
300
301 /* Decompress as much as we can in one pass. */
302 ret = BZ2_bzDecompress(&(state->stream));
303 __archive_read_filter_consume(self->upstream,
304 state->stream.next_in - read_buf);
305
306 switch (ret) {
307 case BZ_STREAM_END: /* Found end of stream. */
308 switch (BZ2_bzDecompressEnd(&(state->stream))) {
309 case BZ_OK:
310 break;
311 default:
312 archive_set_error(&(self->archive->archive),
313 ARCHIVE_ERRNO_MISC,
314 "Failed to clean up decompressor");
315 return (ARCHIVE_FATAL);
316 }
317 state->valid = 0;
318 /* FALLTHROUGH */
319 case BZ_OK: /* Decompressor made some progress. */
320 /* If we filled our buffer, update stats and return. */
321 if (state->stream.avail_out == 0) {
322 *p = state->out_block;
323 decompressed = state->stream.next_out
324 - state->out_block;
325 return (decompressed);
326 }
327 break;
328 default: /* Return an error. */
329 archive_set_error(&self->archive->archive,
330 ARCHIVE_ERRNO_MISC, "bzip decompression failed");
331 return (ARCHIVE_FATAL);
332 }
333 }
334 }
335
336 /*
337 * Clean up the decompressor.
338 */
339 static int
bzip2_filter_close(struct archive_read_filter * self)340 bzip2_filter_close(struct archive_read_filter *self)
341 {
342 struct private_data *state;
343 int ret = ARCHIVE_OK;
344
345 state = (struct private_data *)self->data;
346
347 if (state->valid) {
348 switch (BZ2_bzDecompressEnd(&state->stream)) {
349 case BZ_OK:
350 break;
351 default:
352 archive_set_error(&self->archive->archive,
353 ARCHIVE_ERRNO_MISC,
354 "Failed to clean up decompressor");
355 ret = ARCHIVE_FATAL;
356 }
357 state->valid = 0;
358 }
359
360 free(state->out_block);
361 free(state);
362 return (ret);
363 }
364
365 #endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */
366