contrib/libarchive/libarchive/archive_read_support_compression_bzip2.c

   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: src/lib/libarchive/archive_read_support_compression_bzip2.c,v 1.19 2008/12/06 06:45:15 kientzle Exp $");
  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 HAVE_BZLIB_H
  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
  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 HAVE_BZLIB_H
  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
  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
 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 #ifndef HAVE_BZLIB_H
 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
 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
 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
 210 bzip2_filter_read(struct archive_read_filter *self, const void **p)
 211 {
 212         struct private_data *state;
 213         size_t read_avail, decompressed;
 214         const char *read_buf;
 215         ssize_t ret;
 216
 217         state = (struct private_data *)self->data;
 218         read_avail = 0;
 219
 220         if (state->eof) {
 221                 *p = NULL;
 222                 return (0);
 223         }
 224
 225         /* Empty our output buffer. */
 226         state->stream.next_out = state->out_block;
 227         state->stream.avail_out = state->out_block_size;
 228
 229         /* Try to fill the output buffer. */
 230         for (;;) {
 231                 if (!state->valid) {
 232                         if (bzip2_reader_bid(self->bidder, self->upstream) == 0) {
 233                                 state->eof = 1;
 234                                 *p = state->out_block;
 235                                 decompressed = state->stream.next_out
 236                                     - state->out_block;
 237                                 return (decompressed);
 238                         }
 239                         /* Initialize compression library. */
 240                         ret = BZ2_bzDecompressInit(&(state->stream),
 241                                            0 /* library verbosity */,
 242                                            0 /* don't use low-mem algorithm */);
 243
 244                         /* If init fails, try low-memory algorithm instead. */
 245                         if (ret == BZ_MEM_ERROR)
 246                                 ret = BZ2_bzDecompressInit(&(state->stream),
 247                                            0 /* library verbosity */,
 248                                            1 /* do use low-mem algo */);
 249
 250                         if (ret != BZ_OK) {
 251                                 const char *detail = NULL;
 252                                 int err = ARCHIVE_ERRNO_MISC;
 253                                 switch (ret) {
 254                                 case BZ_PARAM_ERROR:
 255                                         detail = "invalid setup parameter";
 256                                         break;
 257                                 case BZ_MEM_ERROR:
 258                                         err = ENOMEM;
 259                                         detail = "out of memory";
 260                                         break;
 261                                 case BZ_CONFIG_ERROR:
 262                                         detail = "mis-compiled library";
 263                                         break;
 264                                 }
 265                                 archive_set_error(&self->archive->archive, err,
 266                                     "Internal error initializing decompressor%s%s",
 267                                     detail == NULL ? "" : ": ",
 268                                     detail);
 269                                 return (ARCHIVE_FATAL);
 270                         }
 271                         state->valid = 1;
 272                 }
 273
 274                 /* stream.next_in is really const, but bzlib
 275                  * doesn't declare it so. <sigh> */
 276                 read_buf =
 277                     __archive_read_filter_ahead(self->upstream, 1, &ret);
 278                 if (read_buf == NULL)
 279                         return (ARCHIVE_FATAL);
 280                 state->stream.next_in = (char *)(uintptr_t)read_buf;
 281                 state->stream.avail_in = ret;
 282                 /* There is no more data, return whatever we have. */
 283                 if (ret == 0) {
 284                         state->eof = 1;
 285                         *p = state->out_block;
 286                         decompressed = state->stream.next_out
 287                             - state->out_block;
 288                         return (decompressed);
 289                 }
 290
 291                 /* Decompress as much as we can in one pass. */
 292                 ret = BZ2_bzDecompress(&(state->stream));
 293                 __archive_read_filter_consume(self->upstream,
 294                     state->stream.next_in - read_buf);
 295
 296                 switch (ret) {
 297                 case BZ_STREAM_END: /* Found end of stream. */
 298                         switch (BZ2_bzDecompressEnd(&(state->stream))) {
 299                         case BZ_OK:
 300                                 break;
 301                         default:
 302                                 archive_set_error(&(self->archive->archive),
 303                                           ARCHIVE_ERRNO_MISC,
 304                                           "Failed to clean up decompressor");
 305                                 return (ARCHIVE_FATAL);
 306                         }
 307                         state->valid = 0;
 308                         /* FALLTHROUGH */
 309                 case BZ_OK: /* Decompressor made some progress. */
 310                         /* If we filled our buffer, update stats and return. */
 311                         if (state->stream.avail_out == 0) {
 312                                 *p = state->out_block;
 313                                 decompressed = state->stream.next_out
 314                                     - state->out_block;
 315                                 return (decompressed);
 316                         }
 317                         break;
 318                 default: /* Return an error. */
 319                         archive_set_error(&self->archive->archive,
 320                             ARCHIVE_ERRNO_MISC, "bzip decompression failed");
 321                         return (ARCHIVE_FATAL);
 322                 }
 323         }
 324 }
 325
 326 /*
 327  * Clean up the decompressor.
 328  */
 329 static int
 330 bzip2_filter_close(struct archive_read_filter *self)
 331 {
 332         struct private_data *state;
 333         int ret = ARCHIVE_OK;
 334
 335         state = (struct private_data *)self->data;
 336
 337         if (state->valid) {
 338                 switch (BZ2_bzDecompressEnd(&state->stream)) {
 339                 case BZ_OK:
 340                         break;
 341                 default:
 342                         archive_set_error(&self->archive->archive,
 343                                           ARCHIVE_ERRNO_MISC,
 344                                           "Failed to clean up decompressor");
 345                         ret = ARCHIVE_FATAL;
 346                 }
 347         }
 348
 349         free(state->out_block);
 350         free(state);
 351         return (ARCHIVE_OK);
 352 }
 353
 354 #endif /* HAVE_BZLIB_H */