archive_read_support_filter_bzip2.c revision 272461
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) 52struct 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 */ 61static ssize_t bzip2_filter_read(struct archive_read_filter *, const void **); 62static 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 */ 71static int bzip2_reader_bid(struct archive_read_filter_bidder *, struct archive_read_filter *); 72static int bzip2_reader_init(struct archive_read_filter *); 73static int bzip2_reader_free(struct archive_read_filter_bidder *); 74 75#if ARCHIVE_VERSION_NUMBER < 4000000 76/* Deprecated; remove in libarchive 4.0 */ 77int 78archive_read_support_compression_bzip2(struct archive *a) 79{ 80 return archive_read_support_filter_bzip2(a); 81} 82#endif 83 84int 85archive_read_support_filter_bzip2(struct archive *_a) 86{ 87 struct archive_read *a = (struct archive_read *)_a; 88 struct archive_read_filter_bidder *reader; 89 90 archive_check_magic(_a, ARCHIVE_READ_MAGIC, 91 ARCHIVE_STATE_NEW, "archive_read_support_filter_bzip2"); 92 93 if (__archive_read_get_bidder(a, &reader) != ARCHIVE_OK) 94 return (ARCHIVE_FATAL); 95 96 reader->data = NULL; 97 reader->name = "bzip2"; 98 reader->bid = bzip2_reader_bid; 99 reader->init = bzip2_reader_init; 100 reader->options = NULL; 101 reader->free = bzip2_reader_free; 102#if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR) 103 return (ARCHIVE_OK); 104#else 105 archive_set_error(_a, ARCHIVE_ERRNO_MISC, 106 "Using external bzip2 program"); 107 return (ARCHIVE_WARN); 108#endif 109} 110 111static int 112bzip2_reader_free(struct archive_read_filter_bidder *self){ 113 (void)self; /* UNUSED */ 114 return (ARCHIVE_OK); 115} 116 117/* 118 * Test whether we can handle this data. 119 * 120 * This logic returns zero if any part of the signature fails. It 121 * also tries to Do The Right Thing if a very short buffer prevents us 122 * from verifying as much as we would like. 123 */ 124static int 125bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter) 126{ 127 const unsigned char *buffer; 128 ssize_t avail; 129 int bits_checked; 130 131 (void)self; /* UNUSED */ 132 133 /* Minimal bzip2 archive is 14 bytes. */ 134 buffer = __archive_read_filter_ahead(filter, 14, &avail); 135 if (buffer == NULL) 136 return (0); 137 138 /* First three bytes must be "BZh" */ 139 bits_checked = 0; 140 if (memcmp(buffer, "BZh", 3) != 0) 141 return (0); 142 bits_checked += 24; 143 144 /* Next follows a compression flag which must be an ASCII digit. */ 145 if (buffer[3] < '1' || buffer[3] > '9') 146 return (0); 147 bits_checked += 5; 148 149 /* After BZh[1-9], there must be either a data block 150 * which begins with 0x314159265359 or an end-of-data 151 * marker of 0x177245385090. */ 152 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0) 153 bits_checked += 48; 154 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0) 155 bits_checked += 48; 156 else 157 return (0); 158 159 return (bits_checked); 160} 161 162#if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR) 163 164/* 165 * If we don't have the library on this system, we can't actually do the 166 * decompression. We can, however, still detect compressed archives 167 * and emit a useful message. 168 */ 169static int 170bzip2_reader_init(struct archive_read_filter *self) 171{ 172 int r; 173 174 r = __archive_read_program(self, "bzip2 -d"); 175 /* Note: We set the format here even if __archive_read_program() 176 * above fails. We do, after all, know what the format is 177 * even if we weren't able to read it. */ 178 self->code = ARCHIVE_FILTER_BZIP2; 179 self->name = "bzip2"; 180 return (r); 181} 182 183 184#else 185 186/* 187 * Setup the callbacks. 188 */ 189static int 190bzip2_reader_init(struct archive_read_filter *self) 191{ 192 static const size_t out_block_size = 64 * 1024; 193 void *out_block; 194 struct private_data *state; 195 196 self->code = ARCHIVE_FILTER_BZIP2; 197 self->name = "bzip2"; 198 199 state = (struct private_data *)calloc(sizeof(*state), 1); 200 out_block = (unsigned char *)malloc(out_block_size); 201 if (state == NULL || out_block == NULL) { 202 archive_set_error(&self->archive->archive, ENOMEM, 203 "Can't allocate data for bzip2 decompression"); 204 free(out_block); 205 free(state); 206 return (ARCHIVE_FATAL); 207 } 208 209 self->data = state; 210 state->out_block_size = out_block_size; 211 state->out_block = out_block; 212 self->read = bzip2_filter_read; 213 self->skip = NULL; /* not supported */ 214 self->close = bzip2_filter_close; 215 216 return (ARCHIVE_OK); 217} 218 219/* 220 * Return the next block of decompressed data. 221 */ 222static ssize_t 223bzip2_filter_read(struct archive_read_filter *self, const void **p) 224{ 225 struct private_data *state; 226 size_t decompressed; 227 const char *read_buf; 228 ssize_t ret; 229 230 state = (struct private_data *)self->data; 231 232 if (state->eof) { 233 *p = NULL; 234 return (0); 235 } 236 237 /* Empty our output buffer. */ 238 state->stream.next_out = state->out_block; 239 state->stream.avail_out = state->out_block_size; 240 241 /* Try to fill the output buffer. */ 242 for (;;) { 243 if (!state->valid) { 244 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) { 245 state->eof = 1; 246 *p = state->out_block; 247 decompressed = state->stream.next_out 248 - state->out_block; 249 return (decompressed); 250 } 251 /* Initialize compression library. */ 252 ret = BZ2_bzDecompressInit(&(state->stream), 253 0 /* library verbosity */, 254 0 /* don't use low-mem algorithm */); 255 256 /* If init fails, try low-memory algorithm instead. */ 257 if (ret == BZ_MEM_ERROR) 258 ret = BZ2_bzDecompressInit(&(state->stream), 259 0 /* library verbosity */, 260 1 /* do use low-mem algo */); 261 262 if (ret != BZ_OK) { 263 const char *detail = NULL; 264 int err = ARCHIVE_ERRNO_MISC; 265 switch (ret) { 266 case BZ_PARAM_ERROR: 267 detail = "invalid setup parameter"; 268 break; 269 case BZ_MEM_ERROR: 270 err = ENOMEM; 271 detail = "out of memory"; 272 break; 273 case BZ_CONFIG_ERROR: 274 detail = "mis-compiled library"; 275 break; 276 } 277 archive_set_error(&self->archive->archive, err, 278 "Internal error initializing decompressor%s%s", 279 detail == NULL ? "" : ": ", 280 detail); 281 return (ARCHIVE_FATAL); 282 } 283 state->valid = 1; 284 } 285 286 /* stream.next_in is really const, but bzlib 287 * doesn't declare it so. <sigh> */ 288 read_buf = 289 __archive_read_filter_ahead(self->upstream, 1, &ret); 290 if (read_buf == NULL) { 291 archive_set_error(&self->archive->archive, 292 ARCHIVE_ERRNO_MISC, 293 "truncated bzip2 input"); 294 return (ARCHIVE_FATAL); 295 } 296 state->stream.next_in = (char *)(uintptr_t)read_buf; 297 state->stream.avail_in = ret; 298 /* There is no more data, return whatever we have. */ 299 if (ret == 0) { 300 state->eof = 1; 301 *p = state->out_block; 302 decompressed = state->stream.next_out 303 - state->out_block; 304 return (decompressed); 305 } 306 307 /* Decompress as much as we can in one pass. */ 308 ret = BZ2_bzDecompress(&(state->stream)); 309 __archive_read_filter_consume(self->upstream, 310 state->stream.next_in - read_buf); 311 312 switch (ret) { 313 case BZ_STREAM_END: /* Found end of stream. */ 314 switch (BZ2_bzDecompressEnd(&(state->stream))) { 315 case BZ_OK: 316 break; 317 default: 318 archive_set_error(&(self->archive->archive), 319 ARCHIVE_ERRNO_MISC, 320 "Failed to clean up decompressor"); 321 return (ARCHIVE_FATAL); 322 } 323 state->valid = 0; 324 /* FALLTHROUGH */ 325 case BZ_OK: /* Decompressor made some progress. */ 326 /* If we filled our buffer, update stats and return. */ 327 if (state->stream.avail_out == 0) { 328 *p = state->out_block; 329 decompressed = state->stream.next_out 330 - state->out_block; 331 return (decompressed); 332 } 333 break; 334 default: /* Return an error. */ 335 archive_set_error(&self->archive->archive, 336 ARCHIVE_ERRNO_MISC, "bzip decompression failed"); 337 return (ARCHIVE_FATAL); 338 } 339 } 340} 341 342/* 343 * Clean up the decompressor. 344 */ 345static int 346bzip2_filter_close(struct archive_read_filter *self) 347{ 348 struct private_data *state; 349 int ret = ARCHIVE_OK; 350 351 state = (struct private_data *)self->data; 352 353 if (state->valid) { 354 switch (BZ2_bzDecompressEnd(&state->stream)) { 355 case BZ_OK: 356 break; 357 default: 358 archive_set_error(&self->archive->archive, 359 ARCHIVE_ERRNO_MISC, 360 "Failed to clean up decompressor"); 361 ret = ARCHIVE_FATAL; 362 } 363 state->valid = 0; 364 } 365 366 free(state->out_block); 367 free(state); 368 return (ret); 369} 370 371#endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */ 372