/src/libzip/lib/zip_algorithm_xz.c

Source (jump to first uncovered line)
/*
  zip_algorithm_xz.c -- LZMA/XZ (de)compression routines
  Bazed on zip_algorithm_deflate.c -- deflate (de)compression routines
  Copyright (C) 2017-2023 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 <limits.h>
#include <lzma.h>
#include <stdlib.h>
#include <zlib.h>

enum header_state { INCOMPLETE, OUTPUT, DONE };

#define HEADER_BYTES_ZIP 9
#define HEADER_MAGIC_LENGTH 4
#define HEADER_MAGIC1_OFFSET 0
#define HEADER_MAGIC2_OFFSET 2
#define HEADER_SIZE_OFFSET 9
#define HEADER_SIZE_LENGTH 8
#define HEADER_PARAMETERS_LENGTH 5
#define HEADER_LZMA_ALONE_LENGTH (HEADER_PARAMETERS_LENGTH + HEADER_SIZE_LENGTH)

struct ctx {
    zip_error_t *error;
    bool compress;
    zip_uint32_t compression_flags;
    bool end_of_input;
    lzma_stream zstr;
    zip_uint16_t method;
    /* header member is used for converting from zip to "lzma alone"
     * format
     *
     * "lzma alone" file format starts with:
     * 5 bytes lzma parameters
     * 8 bytes uncompressed size
     * compressed data
     *
     * zip archive on-disk format starts with
     * 4 bytes magic (first two bytes vary, e.g. 0x0914 or 0x1002, next bytes are 0x0500)
     * 5 bytes lzma parameters
     * compressed data
     *
     * we read the data into a header of the form
     * 4 bytes magic
     * 5 bytes lzma parameters
     * 8 bytes uncompressed size
     */
    zip_uint8_t header[HEADER_MAGIC_LENGTH + HEADER_LZMA_ALONE_LENGTH];
    zip_uint8_t header_bytes_offset;
    enum header_state header_state;
    zip_uint64_t uncompresssed_size;
};


static zip_uint64_t
maximum_compressed_size(zip_uint64_t uncompressed_size) {
    /*
     According to https://sourceforge.net/p/sevenzip/discussion/45797/thread/b6bd62f8/

     1) you can use
     outSize = 1.10 * originalSize + 64 KB.
     in most cases outSize is less then 1.02 from originalSize.
     2) You can try LZMA2, where
     outSize can be = 1.001 * originalSize + 1 KB.
     */
    /* 13 bytes added for lzma alone header */
    zip_uint64_t compressed_size = (zip_uint64_t)((double)uncompressed_size * 1.1) + 64 * 1024 + 13;

    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, zip_uint16_t method) {
    struct ctx *ctx;

    if ((ctx = (struct ctx *)malloc(sizeof(*ctx))) == NULL) {
        zip_error_set(error, ZIP_ER_MEMORY, 0);
        return NULL;
    }

    ctx->error = error;
    ctx->compress = compress;
    if (compression_flags <= 9) {
        ctx->compression_flags = compression_flags;
    } else {
        ctx->compression_flags = 6; /* default value */
    }
    ctx->compression_flags |= LZMA_PRESET_EXTREME;
    ctx->end_of_input = false;
    memset(ctx->header, 0, sizeof(ctx->header));
    ctx->header_bytes_offset = 0;
    if (method == ZIP_CM_LZMA) {
        ctx->header_state = INCOMPLETE;
    }
    else {
        ctx->header_state = DONE;
    }
    memset(&ctx->zstr, 0, sizeof(ctx->zstr));
    ctx->method = method;
    return ctx;
}


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


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


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


static zip_uint16_t
general_purpose_bit_flags(void *ud) {
    struct ctx *ctx = (struct ctx *)ud;

    if (!ctx->compress) {
        return 0;
    }

    if (ctx->method == ZIP_CM_LZMA) {
        /* liblzma always returns an EOS/EOPM marker, see
   * https://sourceforge.net/p/lzmautils/discussion/708858/thread/84c5dbb9/#a5e4/3764 */
  return 1 << 1;
    }
    return 0;
}

static int
map_error(lzma_ret ret) {
    switch (ret) {
    case LZMA_DATA_ERROR:
    case LZMA_UNSUPPORTED_CHECK:
        return ZIP_ER_COMPRESSED_DATA;

    case LZMA_MEM_ERROR:
        return ZIP_ER_MEMORY;

    case LZMA_OPTIONS_ERROR:
        return ZIP_ER_INVAL;

    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;
    lzma_ret ret;

    lzma_options_lzma opt_lzma;
    lzma_lzma_preset(&opt_lzma, ctx->compression_flags);
    lzma_filter filters[] = {
        {.id = (ctx->method == ZIP_CM_LZMA ? LZMA_FILTER_LZMA1 : LZMA_FILTER_LZMA2), .options = &opt_lzma},
        {.id = LZMA_VLI_UNKNOWN, .options = NULL},
    };

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

    if (ctx->compress) {
        if (ctx->method == ZIP_CM_LZMA)
            ret = lzma_alone_encoder(&ctx->zstr, filters[0].options);
        else
            ret = lzma_stream_encoder(&ctx->zstr, filters, LZMA_CHECK_CRC64);
    }
    else {
        if (ctx->method == ZIP_CM_LZMA)
            ret = lzma_alone_decoder(&ctx->zstr, UINT64_MAX);
        else
            ret = lzma_stream_decoder(&ctx->zstr, UINT64_MAX, LZMA_CONCATENATED);
    }

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

    /* If general purpose bits 1 & 2 are both zero, write real uncompressed size in header. */
    if ((attributes->valid & ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS) && (attributes->general_purpose_bit_mask & 0x6) == 0x6 && (attributes->general_purpose_bit_flags & 0x06) == 0 && (st->valid & ZIP_STAT_SIZE)) {
        ctx->uncompresssed_size = st->size;
    }
    else {
        ctx->uncompresssed_size = ZIP_UINT64_MAX;
    }

    return true;
}


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

    lzma_end(&ctx->zstr);
    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;
    }

    /* For decompression of LZMA1: Have we read the full "lzma alone" header yet? */
    if (ctx->method == ZIP_CM_LZMA && !ctx->compress && ctx->header_state == INCOMPLETE) {
        /* if not, get more of the data */
        zip_uint8_t got = (zip_uint8_t)ZIP_MIN(HEADER_BYTES_ZIP - ctx->header_bytes_offset, length);
        (void)memcpy_s(ctx->header + ctx->header_bytes_offset, sizeof(ctx->header) - ctx->header_bytes_offset, data, got);
        ctx->header_bytes_offset += got;
        length -= got;
        data += got;
        /* Do we have a complete header now? */
        if (ctx->header_bytes_offset == HEADER_BYTES_ZIP) {
            Bytef empty_buffer[1];
            zip_buffer_t *buffer;
            /* check magic */
            if (ctx->header[HEADER_MAGIC2_OFFSET] != 0x05 || ctx->header[HEADER_MAGIC2_OFFSET + 1] != 0x00) {
                /* magic does not match */
                zip_error_set(ctx->error, ZIP_ER_COMPRESSED_DATA, 0);
                return false;
            }
            /* set size of uncompressed data in "lzma alone" header to "unknown" */
            if ((buffer = _zip_buffer_new(ctx->header + HEADER_SIZE_OFFSET, HEADER_SIZE_LENGTH)) == NULL) {
                zip_error_set(ctx->error, ZIP_ER_MEMORY, 0);
                return false;
            }
            _zip_buffer_put_64(buffer, ctx->uncompresssed_size);
            _zip_buffer_free(buffer);
            /* Feed header into "lzma alone" decoder, for
             * initialization; this should not produce output. */
            ctx->zstr.next_in = (void *)(ctx->header + HEADER_MAGIC_LENGTH);
            ctx->zstr.avail_in = HEADER_LZMA_ALONE_LENGTH;
            ctx->zstr.total_in = 0;
            ctx->zstr.next_out = empty_buffer;
            ctx->zstr.avail_out = sizeof(*empty_buffer);
            ctx->zstr.total_out = 0;
            /* this just initializes the decoder and does not produce output, so it consumes the complete header */
            if (lzma_code(&ctx->zstr, LZMA_RUN) != LZMA_OK || ctx->zstr.total_out > 0) {
                zip_error_set(ctx->error, ZIP_ER_COMPRESSED_DATA, 0);
                return false;
            }
            ctx->header_state = DONE;
        }
    }
    ctx->zstr.avail_in = (uInt)length;
    ctx->zstr.next_in = (Bytef *)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;
    uInt avail_out;
    lzma_ret ret;
    /* for compression of LZMA1 */
    if (ctx->method == ZIP_CM_LZMA && ctx->compress) {
        if (ctx->header_state == INCOMPLETE) {
            /* write magic to output buffer */
            ctx->header[0] = 0x09;
            ctx->header[1] = 0x14;
            ctx->header[2] = 0x05;
            ctx->header[3] = 0x00;
            /* generate lzma parameters into output buffer */
            ctx->zstr.avail_out = HEADER_LZMA_ALONE_LENGTH;
            ctx->zstr.next_out = ctx->header + HEADER_MAGIC_LENGTH;
            ret = lzma_code(&ctx->zstr, LZMA_RUN);
            if (ret != LZMA_OK || ctx->zstr.avail_out != 0) {
                /* assume that the whole header will be provided with the first call to lzma_code */
                return ZIP_COMPRESSION_ERROR;
            }
            ctx->header_state = OUTPUT;
        }
        if (ctx->header_state == OUTPUT) {
            /* write header */
            zip_uint8_t write_len = (zip_uint8_t)ZIP_MIN(HEADER_BYTES_ZIP - ctx->header_bytes_offset, *length);
            (void)memcpy_s(data, *length, ctx->header + ctx->header_bytes_offset, write_len);
            ctx->header_bytes_offset += write_len;
            *length = write_len;
            if (ctx->header_bytes_offset == HEADER_BYTES_ZIP) {
                ctx->header_state = DONE;
            }
            return ZIP_COMPRESSION_OK;
        }
    }

    avail_out = (uInt)ZIP_MIN(UINT_MAX, *length);
    ctx->zstr.avail_out = avail_out;
    ctx->zstr.next_out = (Bytef *)data;

    ret = lzma_code(&ctx->zstr, ctx->end_of_input ? LZMA_FINISH : LZMA_RUN);
    *length = avail_out - ctx->zstr.avail_out;

    switch (ret) {
    case LZMA_OK:
        return ZIP_COMPRESSION_OK;

    case LZMA_STREAM_END:
        return ZIP_COMPRESSION_END;

    case LZMA_BUF_ERROR:
        if (ctx->zstr.avail_in == 0) {
            return ZIP_COMPRESSION_NEED_DATA;
        }

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

/* Version Required should be set to 63 (6.3) because this compression
   method was only defined in appnote.txt version 6.3.8, but Winzip
   does not unpack it if the value is not 20. */

/* clang-format off */

zip_compression_algorithm_t zip_algorithm_xz_compress = {
    maximum_compressed_size,
    compress_allocate,
    deallocate,
    general_purpose_bit_flags,
    20,
    start,
    end,
    input,
    end_of_input,
    process
};


zip_compression_algorithm_t zip_algorithm_xz_decompress = {
    maximum_compressed_size,
    decompress_allocate,
    deallocate,
    general_purpose_bit_flags,
    20,
    start,
    end,
    input,
    end_of_input,
    process
};

/* clang-format on */

Coverage Report

Created: 2025-07-23 08:18

Line	Count	Source (jump to first uncovered line)
1		/*
2		zip_algorithm_xz.c -- LZMA/XZ (de)compression routines
3		Bazed on zip_algorithm_deflate.c -- deflate (de)compression routines
4		Copyright (C) 2017-2023 Dieter Baron and Thomas Klausner
5
6		This file is part of libzip, a library to manipulate ZIP archives.
7		The authors can be contacted at <info@libzip.org>
8
9		Redistribution and use in source and binary forms, with or without
10		modification, are permitted provided that the following conditions
11		are met:
12		1. Redistributions of source code must retain the above copyright
13		notice, this list of conditions and the following disclaimer.
14		2. Redistributions in binary form must reproduce the above copyright
15		notice, this list of conditions and the following disclaimer in
16		the documentation and/or other materials provided with the
17		distribution.
18		3. The names of the authors may not be used to endorse or promote
19		products derived from this software without specific prior
20		written permission.
21
22		THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
23		OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
24		WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25		ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
26		DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27		DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
28		GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29		INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
30		IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31		OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
32		IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33		*/
34
35		#include "zipint.h"
36
37		#include <limits.h>
38		#include <lzma.h>
39		#include <stdlib.h>
40		#include <zlib.h>
41
42		enum header_state { INCOMPLETE, OUTPUT, DONE };
43
44	0	#define HEADER_BYTES_ZIP 9
45	0	#define HEADER_MAGIC_LENGTH 4
46		#define HEADER_MAGIC1_OFFSET 0
47	0	#define HEADER_MAGIC2_OFFSET 2
48	0	#define HEADER_SIZE_OFFSET 9
49	0	#define HEADER_SIZE_LENGTH 8
50	0	#define HEADER_PARAMETERS_LENGTH 5
51	0	#define HEADER_LZMA_ALONE_LENGTH (HEADER_PARAMETERS_LENGTH + HEADER_SIZE_LENGTH)
52
53		struct ctx {
54		zip_error_t *error;
55		bool compress;
56		zip_uint32_t compression_flags;
57		bool end_of_input;
58		lzma_stream zstr;
59		zip_uint16_t method;
60		/* header member is used for converting from zip to "lzma alone"
61		* format
62		*
63		* "lzma alone" file format starts with:
64		* 5 bytes lzma parameters
65		* 8 bytes uncompressed size
66		* compressed data
67		*
68		* zip archive on-disk format starts with
69		* 4 bytes magic (first two bytes vary, e.g. 0x0914 or 0x1002, next bytes are 0x0500)
70		* 5 bytes lzma parameters
71		* compressed data
72		*
73		* we read the data into a header of the form
74		* 4 bytes magic
75		* 5 bytes lzma parameters
76		* 8 bytes uncompressed size
77		*/
78		zip_uint8_t header[HEADER_MAGIC_LENGTH + HEADER_LZMA_ALONE_LENGTH];
79		zip_uint8_t header_bytes_offset;
80		enum header_state header_state;
81		zip_uint64_t uncompresssed_size;
82		};
83
84
85		static zip_uint64_t
86	0	maximum_compressed_size(zip_uint64_t uncompressed_size) {
87		/*
88		According to https://sourceforge.net/p/sevenzip/discussion/45797/thread/b6bd62f8/
89
90		1) you can use
91		outSize = 1.10 * originalSize + 64 KB.
92		in most cases outSize is less then 1.02 from originalSize.
93		2) You can try LZMA2, where
94		outSize can be = 1.001 * originalSize + 1 KB.
95		*/
96		/* 13 bytes added for lzma alone header */
97	0	zip_uint64_t compressed_size = (zip_uint64_t)((double)uncompressed_size * 1.1) + 64 * 1024 + 13;
98
99	0	if (compressed_size < uncompressed_size) {
100	0	return ZIP_UINT64_MAX;
101	0	}
102	0	return compressed_size;
103	0	}
104
105
106		static void *
107	0	allocate(bool compress, zip_uint32_t compression_flags, zip_error_t *error, zip_uint16_t method) {
108	0	struct ctx *ctx;
109
110	0	if ((ctx = (struct ctx )malloc(sizeof(ctx))) == NULL) {
111	0	zip_error_set(error, ZIP_ER_MEMORY, 0);
112	0	return NULL;
113	0	}
114
115	0	ctx->error = error;
116	0	ctx->compress = compress;
117	0	if (compression_flags <= 9) {
118	0	ctx->compression_flags = compression_flags;
119	0	} else {
120	0	ctx->compression_flags = 6; /* default value */
121	0	}
122	0	ctx->compression_flags \|= LZMA_PRESET_EXTREME;
123	0	ctx->end_of_input = false;
124	0	memset(ctx->header, 0, sizeof(ctx->header));
125	0	ctx->header_bytes_offset = 0;
126	0	if (method == ZIP_CM_LZMA) {
127	0	ctx->header_state = INCOMPLETE;
128	0	}
129	0	else {
130	0	ctx->header_state = DONE;
131	0	}
132	0	memset(&ctx->zstr, 0, sizeof(ctx->zstr));
133	0	ctx->method = method;
134	0	return ctx;
135	0	}
136
137
138		static void *
139	0	compress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t *error) {
140	0	return allocate(true, compression_flags, error, method);
141	0	}
142
143
144		static void *
145	0	decompress_allocate(zip_uint16_t method, zip_uint32_t compression_flags, zip_error_t *error) {
146	0	return allocate(false, compression_flags, error, method);
147	0	}
148
149
150		static void
151	0	deallocate(void *ud) {
152	0	struct ctx ctx = (struct ctx )ud;
153	0	free(ctx);
154	0	}
155
156
157		static zip_uint16_t
158	0	general_purpose_bit_flags(void *ud) {
159	0	struct ctx ctx = (struct ctx )ud;
160
161	0	if (!ctx->compress) {
162	0	return 0;
163	0	}
164
165	0	if (ctx->method == ZIP_CM_LZMA) {
166		/* liblzma always returns an EOS/EOPM marker, see
167		* https://sourceforge.net/p/lzmautils/discussion/708858/thread/84c5dbb9/#a5e4/3764 */
168	0	return 1 << 1;
169	0	}
170	0	return 0;
171	0	}
172
173		static int
174	0	map_error(lzma_ret ret) {
175	0	switch (ret) {
176	0	case LZMA_DATA_ERROR:
177	0	case LZMA_UNSUPPORTED_CHECK:
178	0	return ZIP_ER_COMPRESSED_DATA;
179
180	0	case LZMA_MEM_ERROR:
181	0	return ZIP_ER_MEMORY;
182
183	0	case LZMA_OPTIONS_ERROR:
184	0	return ZIP_ER_INVAL;
185
186	0	default:
187	0	return ZIP_ER_INTERNAL;
188	0	}
189	0	}
190
191
192		static bool
193	0	start(void ud, zip_stat_t st, zip_file_attributes_t *attributes) {
194	0	struct ctx ctx = (struct ctx )ud;
195	0	lzma_ret ret;
196
197	0	lzma_options_lzma opt_lzma;
198	0	lzma_lzma_preset(&opt_lzma, ctx->compression_flags);
199	0	lzma_filter filters[] = {
200	0	{.id = (ctx->method == ZIP_CM_LZMA ? LZMA_FILTER_LZMA1 : LZMA_FILTER_LZMA2), .options = &opt_lzma},
201	0	{.id = LZMA_VLI_UNKNOWN, .options = NULL},
202	0	};
203
204	0	ctx->zstr.avail_in = 0;
205	0	ctx->zstr.next_in = NULL;
206	0	ctx->zstr.avail_out = 0;
207	0	ctx->zstr.next_out = NULL;
208
209	0	if (ctx->compress) {
210	0	if (ctx->method == ZIP_CM_LZMA)
211	0	ret = lzma_alone_encoder(&ctx->zstr, filters[0].options);
212	0	else
213	0	ret = lzma_stream_encoder(&ctx->zstr, filters, LZMA_CHECK_CRC64);
214	0	}
215	0	else {
216	0	if (ctx->method == ZIP_CM_LZMA)
217	0	ret = lzma_alone_decoder(&ctx->zstr, UINT64_MAX);
218	0	else
219	0	ret = lzma_stream_decoder(&ctx->zstr, UINT64_MAX, LZMA_CONCATENATED);
220	0	}
221
222	0	if (ret != LZMA_OK) {
223	0	zip_error_set(ctx->error, map_error(ret), 0);
224	0	return false;
225	0	}
226
227		/* If general purpose bits 1 & 2 are both zero, write real uncompressed size in header. */
228	0	if ((attributes->valid & ZIP_FILE_ATTRIBUTES_GENERAL_PURPOSE_BIT_FLAGS) && (attributes->general_purpose_bit_mask & 0x6) == 0x6 && (attributes->general_purpose_bit_flags & 0x06) == 0 && (st->valid & ZIP_STAT_SIZE)) {
229	0	ctx->uncompresssed_size = st->size;
230	0	}
231	0	else {
232	0	ctx->uncompresssed_size = ZIP_UINT64_MAX;
233	0	}
234
235	0	return true;
236	0	}
237
238
239		static bool
240	0	end(void *ud) {
241	0	struct ctx ctx = (struct ctx )ud;
242
243	0	lzma_end(&ctx->zstr);
244	0	return true;
245	0	}
246
247
248		static bool
249	0	input(void ud, zip_uint8_t data, zip_uint64_t length) {
250	0	struct ctx ctx = (struct ctx )ud;
251
252	0	if (length > UINT_MAX \|\| ctx->zstr.avail_in > 0) {
253	0	zip_error_set(ctx->error, ZIP_ER_INVAL, 0);
254	0	return false;
255	0	}
256
257		/* For decompression of LZMA1: Have we read the full "lzma alone" header yet? */
258	0	if (ctx->method == ZIP_CM_LZMA && !ctx->compress && ctx->header_state == INCOMPLETE) {
259		/* if not, get more of the data */
260	0	zip_uint8_t got = (zip_uint8_t)ZIP_MIN(HEADER_BYTES_ZIP - ctx->header_bytes_offset, length);
261	0	(void)memcpy_s(ctx->header + ctx->header_bytes_offset, sizeof(ctx->header) - ctx->header_bytes_offset, data, got);
262	0	ctx->header_bytes_offset += got;
263	0	length -= got;
264	0	data += got;
265		/* Do we have a complete header now? */
266	0	if (ctx->header_bytes_offset == HEADER_BYTES_ZIP) {
267	0	Bytef empty_buffer[1];
268	0	zip_buffer_t *buffer;
269		/* check magic */
270	0	if (ctx->header[HEADER_MAGIC2_OFFSET] != 0x05 \|\| ctx->header[HEADER_MAGIC2_OFFSET + 1] != 0x00) {
271		/* magic does not match */
272	0	zip_error_set(ctx->error, ZIP_ER_COMPRESSED_DATA, 0);
273	0	return false;
274	0	}
275		/* set size of uncompressed data in "lzma alone" header to "unknown" */
276	0	if ((buffer = _zip_buffer_new(ctx->header + HEADER_SIZE_OFFSET, HEADER_SIZE_LENGTH)) == NULL) {
277	0	zip_error_set(ctx->error, ZIP_ER_MEMORY, 0);
278	0	return false;
279	0	}
280	0	_zip_buffer_put_64(buffer, ctx->uncompresssed_size);
281	0	_zip_buffer_free(buffer);
282		/* Feed header into "lzma alone" decoder, for
283		* initialization; this should not produce output. */
284	0	ctx->zstr.next_in = (void *)(ctx->header + HEADER_MAGIC_LENGTH);
285	0	ctx->zstr.avail_in = HEADER_LZMA_ALONE_LENGTH;
286	0	ctx->zstr.total_in = 0;
287	0	ctx->zstr.next_out = empty_buffer;
288	0	ctx->zstr.avail_out = sizeof(*empty_buffer);
289	0	ctx->zstr.total_out = 0;
290		/* this just initializes the decoder and does not produce output, so it consumes the complete header */
291	0	if (lzma_code(&ctx->zstr, LZMA_RUN) != LZMA_OK \|\| ctx->zstr.total_out > 0) {
292	0	zip_error_set(ctx->error, ZIP_ER_COMPRESSED_DATA, 0);
293	0	return false;
294	0	}
295	0	ctx->header_state = DONE;
296	0	}
297	0	}
298	0	ctx->zstr.avail_in = (uInt)length;
299	0	ctx->zstr.next_in = (Bytef *)data;
300
301	0	return true;
302	0	}
303
304
305	0	static bool end_of_input(void *ud) {
306	0	struct ctx ctx = (struct ctx )ud;
307
308	0	ctx->end_of_input = true;
309	0	return ctx->zstr.avail_in != 0;
310	0	}
311
312
313		static zip_compression_status_t
314	0	process(void ud, zip_uint8_t data, zip_uint64_t *length) {
315	0	struct ctx ctx = (struct ctx )ud;
316	0	uInt avail_out;
317	0	lzma_ret ret;
318		/* for compression of LZMA1 */
319	0	if (ctx->method == ZIP_CM_LZMA && ctx->compress) {
320	0	if (ctx->header_state == INCOMPLETE) {
321		/* write magic to output buffer */
322	0	ctx->header[0] = 0x09;
323	0	ctx->header[1] = 0x14;
324	0	ctx->header[2] = 0x05;
325	0	ctx->header[3] = 0x00;
326		/* generate lzma parameters into output buffer */
327	0	ctx->zstr.avail_out = HEADER_LZMA_ALONE_LENGTH;
328	0	ctx->zstr.next_out = ctx->header + HEADER_MAGIC_LENGTH;
329	0	ret = lzma_code(&ctx->zstr, LZMA_RUN);
330	0	if (ret != LZMA_OK \|\| ctx->zstr.avail_out != 0) {
331		/* assume that the whole header will be provided with the first call to lzma_code */
332	0	return ZIP_COMPRESSION_ERROR;
333	0	}
334	0	ctx->header_state = OUTPUT;
335	0	}
336	0	if (ctx->header_state == OUTPUT) {
337		/* write header */
338	0	zip_uint8_t write_len = (zip_uint8_t)ZIP_MIN(HEADER_BYTES_ZIP - ctx->header_bytes_offset, *length);
339	0	(void)memcpy_s(data, *length, ctx->header + ctx->header_bytes_offset, write_len);
340	0	ctx->header_bytes_offset += write_len;
341	0	*length = write_len;
342	0	if (ctx->header_bytes_offset == HEADER_BYTES_ZIP) {
343	0	ctx->header_state = DONE;
344	0	}
345	0	return ZIP_COMPRESSION_OK;
346	0	}
347	0	}
348
349	0	avail_out = (uInt)ZIP_MIN(UINT_MAX, *length);
350	0	ctx->zstr.avail_out = avail_out;
351	0	ctx->zstr.next_out = (Bytef *)data;
352
353	0	ret = lzma_code(&ctx->zstr, ctx->end_of_input ? LZMA_FINISH : LZMA_RUN);
354	0	*length = avail_out - ctx->zstr.avail_out;
355
356	0	switch (ret) {
357	0	case LZMA_OK:
358	0	return ZIP_COMPRESSION_OK;
359
360	0	case LZMA_STREAM_END:
361	0	return ZIP_COMPRESSION_END;
362
363	0	case LZMA_BUF_ERROR:
364	0	if (ctx->zstr.avail_in == 0) {
365	0	return ZIP_COMPRESSION_NEED_DATA;
366	0	}
367
368		/* fallthrough */
369	0	default:
370	0	zip_error_set(ctx->error, map_error(ret), 0);
371	0	return ZIP_COMPRESSION_ERROR;
372	0	}
373	0	}
374
375		/* Version Required should be set to 63 (6.3) because this compression
376		method was only defined in appnote.txt version 6.3.8, but Winzip
377		does not unpack it if the value is not 20. */
378
379		/* clang-format off */
380
381		zip_compression_algorithm_t zip_algorithm_xz_compress = {
382		maximum_compressed_size,
383		compress_allocate,
384		deallocate,
385		general_purpose_bit_flags,
386		20,
387		start,
388		end,
389		input,
390		end_of_input,
391		process
392		};
393
394
395		zip_compression_algorithm_t zip_algorithm_xz_decompress = {
396		maximum_compressed_size,
397		decompress_allocate,
398		deallocate,
399		general_purpose_bit_flags,
400		20,
401		start,
402		end,
403		input,
404		end_of_input,
405		process
406		};
407
408		/* clang-format on */