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: head/lib/libarchive/archive_read_support_compression_bzip2.c 201108 2009-12-28 03:28:21Z kientzle $");
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 static int bzip2_reader_free(struct archive_read_filter_bidder *);
74
75 int
archive_read_support_compression_bzip2(struct archive * _a)76 archive_read_support_compression_bzip2(struct archive *_a)
77 {
78 struct archive_read *a = (struct archive_read *)_a;
79 struct archive_read_filter_bidder *reader = __archive_read_get_bidder(a);
80
81 if (reader == NULL)
82 return (ARCHIVE_FATAL);
83
84 reader->data = NULL;
85 reader->bid = bzip2_reader_bid;
86 reader->init = bzip2_reader_init;
87 reader->options = NULL;
88 reader->free = bzip2_reader_free;
89 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR)
90 return (ARCHIVE_OK);
91 #else
92 archive_set_error(_a, ARCHIVE_ERRNO_MISC,
93 "Using external bunzip2 program");
94 return (ARCHIVE_WARN);
95 #endif
96 }
97
98 static int
bzip2_reader_free(struct archive_read_filter_bidder * self)99 bzip2_reader_free(struct archive_read_filter_bidder *self){
100 (void)self; /* UNUSED */
101 return (ARCHIVE_OK);
102 }
103
104 /*
105 * Test whether we can handle this data.
106 *
107 * This logic returns zero if any part of the signature fails. It
108 * also tries to Do The Right Thing if a very short buffer prevents us
109 * from verifying as much as we would like.
110 */
111 static int
bzip2_reader_bid(struct archive_read_filter_bidder * self,struct archive_read_filter * filter)112 bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter)
113 {
114 const unsigned char *buffer;
115 ssize_t avail;
116 int bits_checked;
117
118 (void)self; /* UNUSED */
119
120 /* Minimal bzip2 archive is 14 bytes. */
121 buffer = __archive_read_filter_ahead(filter, 14, &avail);
122 if (buffer == NULL)
123 return (0);
124
125 /* First three bytes must be "BZh" */
126 bits_checked = 0;
127 if (buffer[0] != 'B' || buffer[1] != 'Z' || buffer[2] != 'h')
128 return (0);
129 bits_checked += 24;
130
131 /* Next follows a compression flag which must be an ASCII digit. */
132 if (buffer[3] < '1' || buffer[3] > '9')
133 return (0);
134 bits_checked += 5;
135
136 /* After BZh[1-9], there must be either a data block
137 * which begins with 0x314159265359 or an end-of-data
138 * marker of 0x177245385090. */
139 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0)
140 bits_checked += 48;
141 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0)
142 bits_checked += 48;
143 else
144 return (0);
145
146 return (bits_checked);
147 }
148
149 #if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR)
150
151 /*
152 * If we don't have the library on this system, we can't actually do the
153 * decompression. We can, however, still detect compressed archives
154 * and emit a useful message.
155 */
156 static int
bzip2_reader_init(struct archive_read_filter * self)157 bzip2_reader_init(struct archive_read_filter *self)
158 {
159 int r;
160
161 r = __archive_read_program(self, "bunzip2");
162 /* Note: We set the format here even if __archive_read_program()
163 * above fails. We do, after all, know what the format is
164 * even if we weren't able to read it. */
165 self->code = ARCHIVE_COMPRESSION_BZIP2;
166 self->name = "bzip2";
167 return (r);
168 }
169
170
171 #else
172
173 /*
174 * Setup the callbacks.
175 */
176 static int
bzip2_reader_init(struct archive_read_filter * self)177 bzip2_reader_init(struct archive_read_filter *self)
178 {
179 static const size_t out_block_size = 64 * 1024;
180 void *out_block;
181 struct private_data *state;
182
183 self->code = ARCHIVE_COMPRESSION_BZIP2;
184 self->name = "bzip2";
185
186 state = (struct private_data *)calloc(sizeof(*state), 1);
187 out_block = (unsigned char *)malloc(out_block_size);
188 if (self == NULL || state == NULL || out_block == NULL) {
189 archive_set_error(&self->archive->archive, ENOMEM,
190 "Can't allocate data for bzip2 decompression");
191 free(out_block);
192 free(state);
193 return (ARCHIVE_FATAL);
194 }
195
196 self->data = state;
197 state->out_block_size = out_block_size;
198 state->out_block = out_block;
199 self->read = bzip2_filter_read;
200 self->skip = NULL; /* not supported */
201 self->close = bzip2_filter_close;
202
203 return (ARCHIVE_OK);
204 }
205
206 /*
207 * Return the next block of decompressed data.
208 */
209 static ssize_t
bzip2_filter_read(struct archive_read_filter * self,const void ** p)210 bzip2_filter_read(struct archive_read_filter *self, const void **p)
211 {
212 struct private_data *state;
213 size_t decompressed;
214 const char *read_buf;
215 ssize_t ret;
216
217 state = (struct private_data *)self->data;
218
219 if (state->eof) {
220 *p = NULL;
221 return (0);
222 }
223
224 /* Empty our output buffer. */
225 state->stream.next_out = state->out_block;
226 state->stream.avail_out = state->out_block_size;
227
228 /* Try to fill the output buffer. */
229 for (;;) {
230 if (!state->valid) {
231 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) {
232 state->eof = 1;
233 *p = state->out_block;
234 decompressed = state->stream.next_out
235 - state->out_block;
236 return (decompressed);
237 }
238 /* Initialize compression library. */
239 ret = BZ2_bzDecompressInit(&(state->stream),
240 0 /* library verbosity */,
241 0 /* don't use low-mem algorithm */);
242
243 /* If init fails, try low-memory algorithm instead. */
244 if (ret == BZ_MEM_ERROR)
245 ret = BZ2_bzDecompressInit(&(state->stream),
246 0 /* library verbosity */,
247 1 /* do use low-mem algo */);
248
249 if (ret != BZ_OK) {
250 const char *detail = NULL;
251 int err = ARCHIVE_ERRNO_MISC;
252 switch (ret) {
253 case BZ_PARAM_ERROR:
254 detail = "invalid setup parameter";
255 break;
256 case BZ_MEM_ERROR:
257 err = ENOMEM;
258 detail = "out of memory";
259 break;
260 case BZ_CONFIG_ERROR:
261 detail = "mis-compiled library";
262 break;
263 }
264 archive_set_error(&self->archive->archive, err,
265 "Internal error initializing decompressor%s%s",
266 detail == NULL ? "" : ": ",
267 detail);
268 return (ARCHIVE_FATAL);
269 }
270 state->valid = 1;
271 }
272
273 /* stream.next_in is really const, but bzlib
274 * doesn't declare it so. <sigh> */
275 read_buf =
276 __archive_read_filter_ahead(self->upstream, 1, &ret);
277 if (read_buf == NULL)
278 return (ARCHIVE_FATAL);
279 state->stream.next_in = (char *)(uintptr_t)read_buf;
280 state->stream.avail_in = ret;
281 /* There is no more data, return whatever we have. */
282 if (ret == 0) {
283 state->eof = 1;
284 *p = state->out_block;
285 decompressed = state->stream.next_out
286 - state->out_block;
287 return (decompressed);
288 }
289
290 /* Decompress as much as we can in one pass. */
291 ret = BZ2_bzDecompress(&(state->stream));
292 __archive_read_filter_consume(self->upstream,
293 state->stream.next_in - read_buf);
294
295 switch (ret) {
296 case BZ_STREAM_END: /* Found end of stream. */
297 switch (BZ2_bzDecompressEnd(&(state->stream))) {
298 case BZ_OK:
299 break;
300 default:
301 archive_set_error(&(self->archive->archive),
302 ARCHIVE_ERRNO_MISC,
303 "Failed to clean up decompressor");
304 return (ARCHIVE_FATAL);
305 }
306 state->valid = 0;
307 /* FALLTHROUGH */
308 case BZ_OK: /* Decompressor made some progress. */
309 /* If we filled our buffer, update stats and return. */
310 if (state->stream.avail_out == 0) {
311 *p = state->out_block;
312 decompressed = state->stream.next_out
313 - state->out_block;
314 return (decompressed);
315 }
316 break;
317 default: /* Return an error. */
318 archive_set_error(&self->archive->archive,
319 ARCHIVE_ERRNO_MISC, "bzip decompression failed");
320 return (ARCHIVE_FATAL);
321 }
322 }
323 }
324
325 /*
326 * Clean up the decompressor.
327 */
328 static int
bzip2_filter_close(struct archive_read_filter * self)329 bzip2_filter_close(struct archive_read_filter *self)
330 {
331 struct private_data *state;
332 int ret = ARCHIVE_OK;
333
334 state = (struct private_data *)self->data;
335
336 if (state->valid) {
337 switch (BZ2_bzDecompressEnd(&state->stream)) {
338 case BZ_OK:
339 break;
340 default:
341 archive_set_error(&self->archive->archive,
342 ARCHIVE_ERRNO_MISC,
343 "Failed to clean up decompressor");
344 ret = ARCHIVE_FATAL;
345 }
346 }
347
348 free(state->out_block);
349 free(state);
350 return (ret);
351 }
352
353 #endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */
354