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 static int bzip2_reader_free(struct archive_read_filter_bidder *); 74 75 #if ARCHIVE_VERSION_NUMBER < 4000000 76 /* Deprecated; remove in libarchive 4.0 */ 77 int 78 archive_read_support_compression_bzip2(struct archive *a) 79 { 80 return archive_read_support_filter_bzip2(a); 81 } 82 #endif 83 84 int 85 archive_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->bid = bzip2_reader_bid; 98 reader->init = bzip2_reader_init; 99 reader->options = NULL; 100 reader->free = bzip2_reader_free; 101 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR) 102 return (ARCHIVE_OK); 103 #else 104 archive_set_error(_a, ARCHIVE_ERRNO_MISC, 105 "Using external bunzip2 program"); 106 return (ARCHIVE_WARN); 107 #endif 108 } 109 110 static int 111 bzip2_reader_free(struct archive_read_filter_bidder *self){ 112 (void)self; /* UNUSED */ 113 return (ARCHIVE_OK); 114 } 115 116 /* 117 * Test whether we can handle this data. 118 * 119 * This logic returns zero if any part of the signature fails. It 120 * also tries to Do The Right Thing if a very short buffer prevents us 121 * from verifying as much as we would like. 122 */ 123 static int 124 bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter) 125 { 126 const unsigned char *buffer; 127 ssize_t avail; 128 int bits_checked; 129 130 (void)self; /* UNUSED */ 131 132 /* Minimal bzip2 archive is 14 bytes. */ 133 buffer = __archive_read_filter_ahead(filter, 14, &avail); 134 if (buffer == NULL) 135 return (0); 136 137 /* First three bytes must be "BZh" */ 138 bits_checked = 0; 139 if (memcmp(buffer, "BZh", 3) != 0) 140 return (0); 141 bits_checked += 24; 142 143 /* Next follows a compression flag which must be an ASCII digit. */ 144 if (buffer[3] < '1' || buffer[3] > '9') 145 return (0); 146 bits_checked += 5; 147 148 /* After BZh[1-9], there must be either a data block 149 * which begins with 0x314159265359 or an end-of-data 150 * marker of 0x177245385090. */ 151 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0) 152 bits_checked += 48; 153 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0) 154 bits_checked += 48; 155 else 156 return (0); 157 158 return (bits_checked); 159 } 160 161 #if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR) 162 163 /* 164 * If we don't have the library on this system, we can't actually do the 165 * decompression. We can, however, still detect compressed archives 166 * and emit a useful message. 167 */ 168 static int 169 bzip2_reader_init(struct archive_read_filter *self) 170 { 171 int r; 172 173 r = __archive_read_program(self, "bunzip2"); 174 /* Note: We set the format here even if __archive_read_program() 175 * above fails. We do, after all, know what the format is 176 * even if we weren't able to read it. */ 177 self->code = ARCHIVE_COMPRESSION_BZIP2; 178 self->name = "bzip2"; 179 return (r); 180 } 181 182 183 #else 184 185 /* 186 * Setup the callbacks. 187 */ 188 static int 189 bzip2_reader_init(struct archive_read_filter *self) 190 { 191 static const size_t out_block_size = 64 * 1024; 192 void *out_block; 193 struct private_data *state; 194 195 self->code = ARCHIVE_COMPRESSION_BZIP2; 196 self->name = "bzip2"; 197 198 state = (struct private_data *)calloc(sizeof(*state), 1); 199 out_block = (unsigned char *)malloc(out_block_size); 200 if (state == NULL || out_block == NULL) { 201 archive_set_error(&self->archive->archive, ENOMEM, 202 "Can't allocate data for bzip2 decompression"); 203 free(out_block); 204 free(state); 205 return (ARCHIVE_FATAL); 206 } 207 208 self->data = state; 209 state->out_block_size = out_block_size; 210 state->out_block = out_block; 211 self->read = bzip2_filter_read; 212 self->skip = NULL; /* not supported */ 213 self->close = bzip2_filter_close; 214 215 return (ARCHIVE_OK); 216 } 217 218 /* 219 * Return the next block of decompressed data. 220 */ 221 static ssize_t 222 bzip2_filter_read(struct archive_read_filter *self, const void **p) 223 { 224 struct private_data *state; 225 size_t decompressed; 226 const char *read_buf; 227 ssize_t ret; 228 229 state = (struct private_data *)self->data; 230 231 if (state->eof) { 232 *p = NULL; 233 return (0); 234 } 235 236 /* Empty our output buffer. */ 237 state->stream.next_out = state->out_block; 238 state->stream.avail_out = state->out_block_size; 239 240 /* Try to fill the output buffer. */ 241 for (;;) { 242 if (!state->valid) { 243 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) { 244 state->eof = 1; 245 *p = state->out_block; 246 decompressed = state->stream.next_out 247 - state->out_block; 248 return (decompressed); 249 } 250 /* Initialize compression library. */ 251 ret = BZ2_bzDecompressInit(&(state->stream), 252 0 /* library verbosity */, 253 0 /* don't use low-mem algorithm */); 254 255 /* If init fails, try low-memory algorithm instead. */ 256 if (ret == BZ_MEM_ERROR) 257 ret = BZ2_bzDecompressInit(&(state->stream), 258 0 /* library verbosity */, 259 1 /* do use low-mem algo */); 260 261 if (ret != BZ_OK) { 262 const char *detail = NULL; 263 int err = ARCHIVE_ERRNO_MISC; 264 switch (ret) { 265 case BZ_PARAM_ERROR: 266 detail = "invalid setup parameter"; 267 break; 268 case BZ_MEM_ERROR: 269 err = ENOMEM; 270 detail = "out of memory"; 271 break; 272 case BZ_CONFIG_ERROR: 273 detail = "mis-compiled library"; 274 break; 275 } 276 archive_set_error(&self->archive->archive, err, 277 "Internal error initializing decompressor%s%s", 278 detail == NULL ? "" : ": ", 279 detail); 280 return (ARCHIVE_FATAL); 281 } 282 state->valid = 1; 283 } 284 285 /* stream.next_in is really const, but bzlib 286 * doesn't declare it so. <sigh> */ 287 read_buf = 288 __archive_read_filter_ahead(self->upstream, 1, &ret); 289 if (read_buf == NULL) { 290 archive_set_error(&self->archive->archive, 291 ARCHIVE_ERRNO_MISC, 292 "truncated bzip2 input"); 293 return (ARCHIVE_FATAL); 294 } 295 state->stream.next_in = (char *)(uintptr_t)read_buf; 296 state->stream.avail_in = ret; 297 /* There is no more data, return whatever we have. */ 298 if (ret == 0) { 299 state->eof = 1; 300 *p = state->out_block; 301 decompressed = state->stream.next_out 302 - state->out_block; 303 return (decompressed); 304 } 305 306 /* Decompress as much as we can in one pass. */ 307 ret = BZ2_bzDecompress(&(state->stream)); 308 __archive_read_filter_consume(self->upstream, 309 state->stream.next_in - read_buf); 310 311 switch (ret) { 312 case BZ_STREAM_END: /* Found end of stream. */ 313 switch (BZ2_bzDecompressEnd(&(state->stream))) { 314 case BZ_OK: 315 break; 316 default: 317 archive_set_error(&(self->archive->archive), 318 ARCHIVE_ERRNO_MISC, 319 "Failed to clean up decompressor"); 320 return (ARCHIVE_FATAL); 321 } 322 state->valid = 0; 323 /* FALLTHROUGH */ 324 case BZ_OK: /* Decompressor made some progress. */ 325 /* If we filled our buffer, update stats and return. */ 326 if (state->stream.avail_out == 0) { 327 *p = state->out_block; 328 decompressed = state->stream.next_out 329 - state->out_block; 330 return (decompressed); 331 } 332 break; 333 default: /* Return an error. */ 334 archive_set_error(&self->archive->archive, 335 ARCHIVE_ERRNO_MISC, "bzip decompression failed"); 336 return (ARCHIVE_FATAL); 337 } 338 } 339 } 340 341 /* 342 * Clean up the decompressor. 343 */ 344 static int 345 bzip2_filter_close(struct archive_read_filter *self) 346 { 347 struct private_data *state; 348 int ret = ARCHIVE_OK; 349 350 state = (struct private_data *)self->data; 351 352 if (state->valid) { 353 switch (BZ2_bzDecompressEnd(&state->stream)) { 354 case BZ_OK: 355 break; 356 default: 357 archive_set_error(&self->archive->archive, 358 ARCHIVE_ERRNO_MISC, 359 "Failed to clean up decompressor"); 360 ret = ARCHIVE_FATAL; 361 } 362 state->valid = 0; 363 } 364 365 free(state->out_block); 366 free(state); 367 return (ret); 368 } 369 370 #endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */ 371