/src/libzip/lib/zip_algorithm_bzip2.c

Source
/*
  zip_algorithm_bzip2.c -- bzip2 (de)compression routines
  Copyright (C) 2017-2025 Dieter Baron and Thomas Klausner

  This file is part of libzip, a library to manipulate ZIP archives.
  The authors can be contacted at <info@libzip.org>

  Redistribution and use in source and binary forms, with or without
  modification, are permitted provided that the following conditions
  are met:
  1. Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
  2. Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in
     the documentation and/or other materials provided with the
     distribution.
  3. The names of the authors may not be used to endorse or promote
     products derived from this software without specific prior
     written permission.

  THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
  OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#include "zipint.h"

#include <bzlib.h>
#include <limits.h>
#include <stdlib.h>

struct ctx {
    zip_error_t *error;
    bool compress;
    int compression_flags;
    bool end_of_input;
    bz_stream zstr;
};


static zip_uint64_t maximum_compressed_size(zip_uint64_t uncompressed_size) {
    /* According to the bzip2 man page, random data is coded at about 8.05 bits per byte, giving an expansion of around 0.5%. However, in practice the per-block overhead doubles the factor for compression level 1. Add an additional safety factor. */
    zip_uint64_t compressed_size = uncompressed_size + uncompressed_size / 64 + 1024;

    if (compressed_size < uncompressed_size) {
        return ZIP_UINT64_MAX;
    }
    return compressed_size;
}


static void *allocate(bool compress, zip_uint32_t compression_flags, zip_error_t *error) {
    struct ctx *ctx;

    if ((ctx = (struct ctx *)malloc(sizeof(*ctx))) == NULL) {
        return NULL;
    }

    ctx->error = error;
    ctx->compress = compress;
    if (compression_flags >= 1 && compression_flags <= 9) {
        ctx->compression_flags = (int)compression_flags;
    }
    else {
        ctx->compression_flags = 9;
    }
    ctx->end_of_input = false;

    ctx->zstr.bzalloc = NULL;
    ctx->zstr.bzfree = NULL;
    ctx->zstr.opaque = NULL;

    return ctx;
}


static void *compress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t *error) {
    (void)method;
    return allocate(true, compression_flags, error);
}


static void *decompress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t *error) {
    (void)method;
    return allocate(false, compression_flags, error);
}


static void deallocate(void *ud) {
    struct ctx *ctx = (struct ctx *)ud;

    free(ctx);
}


static zip_uint16_t general_purpose_bit_flags(void *ud) {
    (void)ud;
    return 0;
}


static int map_error(int ret) {
    switch (ret) {
    case BZ_FINISH_OK:
    case BZ_FLUSH_OK:
    case BZ_OK:
    case BZ_RUN_OK:
    case BZ_STREAM_END:
        return ZIP_ER_OK;

    case BZ_DATA_ERROR:
    case BZ_DATA_ERROR_MAGIC:
    case BZ_UNEXPECTED_EOF:
        return ZIP_ER_COMPRESSED_DATA;

    case BZ_MEM_ERROR:
        return ZIP_ER_MEMORY;

    case BZ_PARAM_ERROR:
        return ZIP_ER_INVAL;

    case BZ_CONFIG_ERROR: /* actually, bzip2 miscompiled */
    case BZ_IO_ERROR:
    case BZ_OUTBUFF_FULL:
    case BZ_SEQUENCE_ERROR:
    default:
        return ZIP_ER_INTERNAL;
    }
}

static bool start(void *ud, zip_stat_t *st, zip_file_attributes_t *attributes) {
    struct ctx *ctx = (struct ctx *)ud;
    int ret;

    (void)st;
    (void)attributes;

    ctx->zstr.avail_in = 0;
    ctx->zstr.next_in = NULL;
    ctx->zstr.avail_out = 0;
    ctx->zstr.next_out = NULL;

    if (ctx->compress) {
        ret = BZ2_bzCompressInit(&ctx->zstr, ctx->compression_flags, 0, 30);
    }
    else {
        ret = BZ2_bzDecompressInit(&ctx->zstr, 0, 0);
    }

    if (ret != BZ_OK) {
        zip_error_set(ctx->error, map_error(ret), 0);
        return false;
    }

    return true;
}


static bool end(void *ud) {
    struct ctx *ctx = (struct ctx *)ud;
    int err;

    if (ctx->compress) {
        err = BZ2_bzCompressEnd(&ctx->zstr);
    }
    else {
        err = BZ2_bzDecompressEnd(&ctx->zstr);
    }

    if (err != BZ_OK) {
        zip_error_set(ctx->error, map_error(err), 0);
        return false;
    }

    return true;
}


static bool input(void *ud, zip_uint8_t *data, zip_uint64_t length) {
    struct ctx *ctx = (struct ctx *)ud;

    if (length > UINT_MAX || ctx->zstr.avail_in > 0) {
        zip_error_set(ctx->error, ZIP_ER_INVAL, 0);
        return false;
    }

    ctx->zstr.avail_in = (unsigned int)length;
    ctx->zstr.next_in = (char *)data;

    return true;
}


static bool end_of_input(void *ud) {
    struct ctx *ctx = (struct ctx *)ud;

    ctx->end_of_input = true;
    return ctx->zstr.avail_in != 0;
}


static zip_compression_status_t process(void *ud, zip_uint8_t *data, zip_uint64_t *length) {
    struct ctx *ctx = (struct ctx *)ud;
    unsigned int avail_out;

    int ret;

    if (ctx->zstr.avail_in == 0 && !ctx->end_of_input) {
        *length = 0;
        return ZIP_COMPRESSION_NEED_DATA;
    }

    avail_out = (unsigned int)ZIP_MIN(UINT_MAX, *length);
    ctx->zstr.avail_out = avail_out;
    ctx->zstr.next_out = (char *)data;

    if (ctx->compress) {
        ret = BZ2_bzCompress(&ctx->zstr, ctx->end_of_input ? BZ_FINISH : BZ_RUN);
    }
    else {
        ret = BZ2_bzDecompress(&ctx->zstr);
    }

    *length = avail_out - ctx->zstr.avail_out;

    switch (ret) {
    case BZ_FINISH_OK: /* compression */
        return ZIP_COMPRESSION_OK;

    case BZ_OK:     /* decompression */
    case BZ_RUN_OK: /* compression */
        if (ctx->zstr.avail_in == 0) {
            return ZIP_COMPRESSION_NEED_DATA;
        }
        return ZIP_COMPRESSION_OK;

    case BZ_STREAM_END:
        return ZIP_COMPRESSION_END;

    default:
        zip_error_set(ctx->error, map_error(ret), 0);
        return ZIP_COMPRESSION_ERROR;
    }
}

/* clang-format off */

zip_compression_algorithm_t zip_algorithm_bzip2_compress = {
    maximum_compressed_size,
    compress_allocate,
    deallocate,
    general_purpose_bit_flags,
    46,
    start,
    end,
    input,
    end_of_input,
    process
};


zip_compression_algorithm_t zip_algorithm_bzip2_decompress = {
    maximum_compressed_size,
    decompress_allocate,
    deallocate,
    general_purpose_bit_flags,
    46,
    start,
    end,
    input,
    end_of_input,
    process
};

/* clang-format on */

Coverage Report

Created: 2026-10-28 07:26

Line	Count	Source
1		/*
2		zip_algorithm_bzip2.c -- bzip2 (de)compression routines
3		Copyright (C) 2017-2025 Dieter Baron and Thomas Klausner
4
5		This file is part of libzip, a library to manipulate ZIP archives.
6		The authors can be contacted at <info@libzip.org>
7
8		Redistribution and use in source and binary forms, with or without
9		modification, are permitted provided that the following conditions
10		are met:
11		1. Redistributions of source code must retain the above copyright
12		notice, this list of conditions and the following disclaimer.
13		2. Redistributions in binary form must reproduce the above copyright
14		notice, this list of conditions and the following disclaimer in
15		the documentation and/or other materials provided with the
16		distribution.
17		3. The names of the authors may not be used to endorse or promote
18		products derived from this software without specific prior
19		written permission.
20
21		THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
22		OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24		ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26		DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27		GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28		INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
29		IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30		OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
31		IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32		*/
33
34		#include "zipint.h"
35
36		#include <bzlib.h>
37		#include <limits.h>
38		#include <stdlib.h>
39
40		struct ctx {
41		zip_error_t *error;
42		bool compress;
43		int compression_flags;
44		bool end_of_input;
45		bz_stream zstr;
46		};
47
48
49	0	static zip_uint64_t maximum_compressed_size(zip_uint64_t uncompressed_size) {
50		/* According to the bzip2 man page, random data is coded at about 8.05 bits per byte, giving an expansion of around 0.5%. However, in practice the per-block overhead doubles the factor for compression level 1. Add an additional safety factor. */
51	0	zip_uint64_t compressed_size = uncompressed_size + uncompressed_size / 64 + 1024;
52
53	0	if (compressed_size < uncompressed_size) {
54	0	return ZIP_UINT64_MAX;
55	0	}
56	0	return compressed_size;
57	0	}
58
59
60	0	static void allocate(bool compress, zip_uint32_t compression_flags, zip_error_t error) {
61	0	struct ctx *ctx;
62
63	0	if ((ctx = (struct ctx )malloc(sizeof(ctx))) == NULL) {
64	0	return NULL;
65	0	}
66
67	0	ctx->error = error;
68	0	ctx->compress = compress;
69	0	if (compression_flags >= 1 && compression_flags <= 9) {
70	0	ctx->compression_flags = (int)compression_flags;
71	0	}
72	0	else {
73	0	ctx->compression_flags = 9;
74	0	}
75	0	ctx->end_of_input = false;
76
77	0	ctx->zstr.bzalloc = NULL;
78	0	ctx->zstr.bzfree = NULL;
79	0	ctx->zstr.opaque = NULL;
80
81	0	return ctx;
82	0	}
83
84
85	0	static void compress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t error) {
86	0	(void)method;
87	0	return allocate(true, compression_flags, error);
88	0	}
89
90
91	0	static void decompress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t error) {
92	0	(void)method;
93	0	return allocate(false, compression_flags, error);
94	0	}
95
96
97	0	static void deallocate(void *ud) {
98	0	struct ctx ctx = (struct ctx )ud;
99
100	0	free(ctx);
101	0	}
102
103
104	0	static zip_uint16_t general_purpose_bit_flags(void *ud) {
105	0	(void)ud;
106	0	return 0;
107	0	}
108
109
110	0	static int map_error(int ret) {
111	0	switch (ret) {
112	0	case BZ_FINISH_OK:
113	0	case BZ_FLUSH_OK:
114	0	case BZ_OK:
115	0	case BZ_RUN_OK:
116	0	case BZ_STREAM_END:
117	0	return ZIP_ER_OK;
118
119	0	case BZ_DATA_ERROR:
120	0	case BZ_DATA_ERROR_MAGIC:
121	0	case BZ_UNEXPECTED_EOF:
122	0	return ZIP_ER_COMPRESSED_DATA;
123
124	0	case BZ_MEM_ERROR:
125	0	return ZIP_ER_MEMORY;
126
127	0	case BZ_PARAM_ERROR:
128	0	return ZIP_ER_INVAL;
129
130	0	case BZ_CONFIG_ERROR: /* actually, bzip2 miscompiled */
131	0	case BZ_IO_ERROR:
132	0	case BZ_OUTBUFF_FULL:
133	0	case BZ_SEQUENCE_ERROR:
134	0	default:
135	0	return ZIP_ER_INTERNAL;
136	0	}
137	0	}
138
139	0	static bool start(void ud, zip_stat_t st, zip_file_attributes_t *attributes) {
140	0	struct ctx ctx = (struct ctx )ud;
141	0	int ret;
142
143	0	(void)st;
144	0	(void)attributes;
145
146	0	ctx->zstr.avail_in = 0;
147	0	ctx->zstr.next_in = NULL;
148	0	ctx->zstr.avail_out = 0;
149	0	ctx->zstr.next_out = NULL;
150
151	0	if (ctx->compress) {
152	0	ret = BZ2_bzCompressInit(&ctx->zstr, ctx->compression_flags, 0, 30);
153	0	}
154	0	else {
155	0	ret = BZ2_bzDecompressInit(&ctx->zstr, 0, 0);
156	0	}
157
158	0	if (ret != BZ_OK) {
159	0	zip_error_set(ctx->error, map_error(ret), 0);
160	0	return false;
161	0	}
162
163	0	return true;
164	0	}
165
166
167	0	static bool end(void *ud) {
168	0	struct ctx ctx = (struct ctx )ud;
169	0	int err;
170
171	0	if (ctx->compress) {
172	0	err = BZ2_bzCompressEnd(&ctx->zstr);
173	0	}
174	0	else {
175	0	err = BZ2_bzDecompressEnd(&ctx->zstr);
176	0	}
177
178	0	if (err != BZ_OK) {
179	0	zip_error_set(ctx->error, map_error(err), 0);
180	0	return false;
181	0	}
182
183	0	return true;
184	0	}
185
186
187	0	static bool input(void ud, zip_uint8_t data, zip_uint64_t length) {
188	0	struct ctx ctx = (struct ctx )ud;
189
190	0	if (length > UINT_MAX \|\| ctx->zstr.avail_in > 0) {
191	0	zip_error_set(ctx->error, ZIP_ER_INVAL, 0);
192	0	return false;
193	0	}
194
195	0	ctx->zstr.avail_in = (unsigned int)length;
196	0	ctx->zstr.next_in = (char *)data;
197
198	0	return true;
199	0	}
200
201
202	0	static bool end_of_input(void *ud) {
203	0	struct ctx ctx = (struct ctx )ud;
204
205	0	ctx->end_of_input = true;
206	0	return ctx->zstr.avail_in != 0;
207	0	}
208
209
210	0	static zip_compression_status_t process(void ud, zip_uint8_t data, zip_uint64_t *length) {
211	0	struct ctx ctx = (struct ctx )ud;
212	0	unsigned int avail_out;
213
214	0	int ret;
215
216	0	if (ctx->zstr.avail_in == 0 && !ctx->end_of_input) {
217	0	*length = 0;
218	0	return ZIP_COMPRESSION_NEED_DATA;
219	0	}
220
221	0	avail_out = (unsigned int)ZIP_MIN(UINT_MAX, *length);
222	0	ctx->zstr.avail_out = avail_out;
223	0	ctx->zstr.next_out = (char *)data;
224
225	0	if (ctx->compress) {
226	0	ret = BZ2_bzCompress(&ctx->zstr, ctx->end_of_input ? BZ_FINISH : BZ_RUN);
227	0	}
228	0	else {
229	0	ret = BZ2_bzDecompress(&ctx->zstr);
230	0	}
231
232	0	*length = avail_out - ctx->zstr.avail_out;
233
234	0	switch (ret) {
235	0	case BZ_FINISH_OK: /* compression */
236	0	return ZIP_COMPRESSION_OK;
237
238	0	case BZ_OK: /* decompression */
239	0	case BZ_RUN_OK: /* compression */
240	0	if (ctx->zstr.avail_in == 0) {
241	0	return ZIP_COMPRESSION_NEED_DATA;
242	0	}
243	0	return ZIP_COMPRESSION_OK;
244
245	0	case BZ_STREAM_END:
246	0	return ZIP_COMPRESSION_END;
247
248	0	default:
249	0	zip_error_set(ctx->error, map_error(ret), 0);
250	0	return ZIP_COMPRESSION_ERROR;
251	0	}
252	0	}
253
254		/* clang-format off */
255
256		zip_compression_algorithm_t zip_algorithm_bzip2_compress = {
257		maximum_compressed_size,
258		compress_allocate,
259		deallocate,
260		general_purpose_bit_flags,
261		46,
262		start,
263		end,
264		input,
265		end_of_input,
266		process
267		};
268
269
270		zip_compression_algorithm_t zip_algorithm_bzip2_decompress = {
271		maximum_compressed_size,
272		decompress_allocate,
273		deallocate,
274		general_purpose_bit_flags,
275		46,
276		start,
277		end,
278		input,
279		end_of_input,
280		process
281		};
282
283		/* clang-format on */