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 #ifdef HAVE_ERRNO_H
29 #include <errno.h>
30 #endif
31 #include <stdio.h>
32 #ifdef HAVE_STDLIB_H
33 #include <stdlib.h>
34 #endif
35 #ifdef HAVE_STRING_H
36 #include <string.h>
37 #endif
38 #ifdef HAVE_UNISTD_H
39 #include <unistd.h>
40 #endif
41 #ifdef HAVE_BZLIB_H
42 #include <bzlib.h>
43 #endif
44
45 #include "archive.h"
46 #include "archive_private.h"
47 #include "archive_read_private.h"
48
49 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR)
50 struct private_data {
51 bz_stream stream;
52 char *out_block;
53 size_t out_block_size;
54 char valid; /* True = decompressor is initialized */
55 char eof; /* True = found end of compressed data. */
56 };
57
58 /* Bzip2 filter */
59 static ssize_t bzip2_filter_read(struct archive_read_filter *, const void **);
60 static int bzip2_filter_close(struct archive_read_filter *);
61 #endif
62
63 /*
64 * Note that we can detect bzip2 archives even if we can't decompress
65 * them. (In fact, we like detecting them because we can give better
66 * error messages.) So the bid framework here gets compiled even
67 * if bzlib is unavailable.
68 */
69 static int bzip2_reader_bid(struct archive_read_filter_bidder *, struct archive_read_filter *);
70 static int bzip2_reader_init(struct archive_read_filter *);
71
72 #if ARCHIVE_VERSION_NUMBER < 4000000
73 /* Deprecated; remove in libarchive 4.0 */
74 int
archive_read_support_compression_bzip2(struct archive * a)75 archive_read_support_compression_bzip2(struct archive *a)
76 {
77 return archive_read_support_filter_bzip2(a);
78 }
79 #endif
80
81 static const struct archive_read_filter_bidder_vtable
82 bzip2_bidder_vtable = {
83 .bid = bzip2_reader_bid,
84 .init = bzip2_reader_init,
85 };
86
87 int
archive_read_support_filter_bzip2(struct archive * _a)88 archive_read_support_filter_bzip2(struct archive *_a)
89 {
90 struct archive_read *a = (struct archive_read *)_a;
91
92 if (__archive_read_register_bidder(a, NULL, "bzip2",
93 &bzip2_bidder_vtable) != ARCHIVE_OK)
94 return (ARCHIVE_FATAL);
95
96 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR)
97 return (ARCHIVE_OK);
98 #else
99 archive_set_error(_a, ARCHIVE_ERRNO_MISC,
100 "Using external bzip2 program");
101 return (ARCHIVE_WARN);
102 #endif
103 }
104
105 /*
106 * Test whether we can handle this data.
107 *
108 * This logic returns zero if any part of the signature fails. It
109 * also tries to Do The Right Thing if a very short buffer prevents us
110 * from verifying as much as we would like.
111 */
112 static int
bzip2_reader_bid(struct archive_read_filter_bidder * self,struct archive_read_filter * filter)113 bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter)
114 {
115 const unsigned char *buffer;
116 ssize_t avail;
117 int bits_checked;
118
119 (void)self; /* UNUSED */
120
121 /* Minimal bzip2 archive is 14 bytes. */
122 buffer = __archive_read_filter_ahead(filter, 14, &avail);
123 if (buffer == NULL)
124 return (0);
125
126 /* First three bytes must be "BZh" */
127 bits_checked = 0;
128 if (memcmp(buffer, "BZh", 3) != 0)
129 return (0);
130 bits_checked += 24;
131
132 /* Next follows a compression flag which must be an ASCII digit. */
133 if (buffer[3] < '1' || buffer[3] > '9')
134 return (0);
135 bits_checked += 5;
136
137 /* After BZh[1-9], there must be either a data block
138 * which begins with 0x314159265359 or an end-of-data
139 * marker of 0x177245385090. */
140 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0)
141 bits_checked += 48;
142 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0)
143 bits_checked += 48;
144 else
145 return (0);
146
147 return (bits_checked);
148 }
149
150 #if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR)
151
152 /*
153 * If we don't have the library on this system, we can't actually do the
154 * decompression. We can, however, still detect compressed archives
155 * and emit a useful message.
156 */
157 static int
bzip2_reader_init(struct archive_read_filter * self)158 bzip2_reader_init(struct archive_read_filter *self)
159 {
160 int r;
161
162 r = __archive_read_program(self, "bzip2 -d");
163 /* Note: We set the format here even if __archive_read_program()
164 * above fails. We do, after all, know what the format is
165 * even if we weren't able to read it. */
166 self->code = ARCHIVE_FILTER_BZIP2;
167 self->name = "bzip2";
168 return (r);
169 }
170
171
172 #else
173
174 static const struct archive_read_filter_vtable
175 bzip2_reader_vtable = {
176 .read = bzip2_filter_read,
177 .close = bzip2_filter_close,
178 };
179
180 /*
181 * Setup the callbacks.
182 */
183 static int
bzip2_reader_init(struct archive_read_filter * self)184 bzip2_reader_init(struct archive_read_filter *self)
185 {
186 static const size_t out_block_size = 64 * 1024;
187 void *out_block;
188 struct private_data *state;
189
190 self->code = ARCHIVE_FILTER_BZIP2;
191 self->name = "bzip2";
192
193 state = calloc(1, sizeof(*state));
194 out_block = malloc(out_block_size);
195 if (state == NULL || out_block == NULL) {
196 archive_set_error(&self->archive->archive, ENOMEM,
197 "Can't allocate data for bzip2 decompression");
198 free(out_block);
199 free(state);
200 return (ARCHIVE_FATAL);
201 }
202
203 self->data = state;
204 state->out_block_size = out_block_size;
205 state->out_block = out_block;
206 self->vtable = &bzip2_reader_vtable;
207
208 return (ARCHIVE_OK);
209 }
210
211 /*
212 * Return the next block of decompressed data.
213 */
214 static ssize_t
bzip2_filter_read(struct archive_read_filter * self,const void ** p)215 bzip2_filter_read(struct archive_read_filter *self, const void **p)
216 {
217 struct private_data *state;
218 size_t decompressed;
219 const char *read_buf;
220 ssize_t ret;
221
222 state = (struct private_data *)self->data;
223
224 if (state->eof) {
225 *p = NULL;
226 return (0);
227 }
228
229 /* Empty our output buffer. */
230 state->stream.next_out = state->out_block;
231 state->stream.avail_out = (uint32_t)state->out_block_size;
232
233 /* Try to fill the output buffer. */
234 for (;;) {
235 if (!state->valid) {
236 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) {
237 state->eof = 1;
238 *p = state->out_block;
239 decompressed = state->stream.next_out
240 - state->out_block;
241 return (decompressed);
242 }
243 /* Initialize compression library. */
244 ret = BZ2_bzDecompressInit(&(state->stream),
245 0 /* library verbosity */,
246 0 /* don't use low-mem algorithm */);
247
248 /* If init fails, try low-memory algorithm instead. */
249 if (ret == BZ_MEM_ERROR)
250 ret = BZ2_bzDecompressInit(&(state->stream),
251 0 /* library verbosity */,
252 1 /* do use low-mem algo */);
253
254 if (ret != BZ_OK) {
255 const char *detail = NULL;
256 int err = ARCHIVE_ERRNO_MISC;
257 switch (ret) {
258 case BZ_PARAM_ERROR:
259 detail = "invalid setup parameter";
260 break;
261 case BZ_MEM_ERROR:
262 err = ENOMEM;
263 detail = "out of memory";
264 break;
265 case BZ_CONFIG_ERROR:
266 detail = "mis-compiled library";
267 break;
268 }
269 archive_set_error(&self->archive->archive, err,
270 "Internal error initializing decompressor%s%s",
271 detail == NULL ? "" : ": ",
272 detail);
273 return (ARCHIVE_FATAL);
274 }
275 state->valid = 1;
276 }
277
278 /* stream.next_in is really const, but bzlib
279 * doesn't declare it so. <sigh> */
280 read_buf =
281 __archive_read_filter_ahead(self->upstream, 1, &ret);
282 if (read_buf == NULL) {
283 archive_set_error(&self->archive->archive,
284 ARCHIVE_ERRNO_MISC,
285 "truncated bzip2 input");
286 return (ARCHIVE_FATAL);
287 }
288 state->stream.next_in = (char *)(uintptr_t)read_buf;
289 state->stream.avail_in = (uint32_t)ret;
290 /* There is no more data, return whatever we have. */
291 if (ret == 0) {
292 state->eof = 1;
293 *p = state->out_block;
294 decompressed = state->stream.next_out
295 - state->out_block;
296 return (decompressed);
297 }
298
299 /* Decompress as much as we can in one pass. */
300 ret = BZ2_bzDecompress(&(state->stream));
301 __archive_read_filter_consume(self->upstream,
302 state->stream.next_in - read_buf);
303
304 switch (ret) {
305 case BZ_STREAM_END: /* Found end of stream. */
306 switch (BZ2_bzDecompressEnd(&(state->stream))) {
307 case BZ_OK:
308 break;
309 default:
310 archive_set_error(&(self->archive->archive),
311 ARCHIVE_ERRNO_MISC,
312 "Failed to clean up decompressor");
313 return (ARCHIVE_FATAL);
314 }
315 state->valid = 0;
316 /* FALLTHROUGH */
317 case BZ_OK: /* Decompressor made some progress. */
318 /* If we filled our buffer, update stats and return. */
319 if (state->stream.avail_out == 0) {
320 *p = state->out_block;
321 decompressed = state->stream.next_out
322 - state->out_block;
323 return (decompressed);
324 }
325 break;
326 default: /* Return an error. */
327 archive_set_error(&self->archive->archive,
328 ARCHIVE_ERRNO_MISC, "bzip decompression failed");
329 return (ARCHIVE_FATAL);
330 }
331 }
332 }
333
334 /*
335 * Clean up the decompressor.
336 */
337 static int
bzip2_filter_close(struct archive_read_filter * self)338 bzip2_filter_close(struct archive_read_filter *self)
339 {
340 struct private_data *state;
341 int ret = ARCHIVE_OK;
342
343 state = (struct private_data *)self->data;
344
345 if (state->valid) {
346 switch (BZ2_bzDecompressEnd(&state->stream)) {
347 case BZ_OK:
348 break;
349 default:
350 archive_set_error(&self->archive->archive,
351 ARCHIVE_ERRNO_MISC,
352 "Failed to clean up decompressor");
353 ret = ARCHIVE_FATAL;
354 }
355 state->valid = 0;
356 }
357
358 free(state->out_block);
359 free(state);
360 return (ret);
361 }
362
363 #endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */
364