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: head/lib/libarchive/archive_write_set_compression_gzip.c 201081 2009-12-28 02:04:42Z kientzle $");
29 
30 #ifdef HAVE_ERRNO_H
31 #include <errno.h>
32 #endif
33 #ifdef HAVE_STDLIB_H
34 #include <stdlib.h>
35 #endif
36 #ifdef HAVE_STRING_H
37 #include <string.h>
38 #endif
39 #include <time.h>
40 #ifdef HAVE_ZLIB_H
41 #include <zlib.h>
42 #endif
43 
44 #include "archive.h"
45 #include "archive_private.h"
46 #include "archive_write_private.h"
47 
48 #if ARCHIVE_VERSION_NUMBER < 4000000
49 int
50 archive_write_set_compression_gzip(struct archive *a)
51 {
52 	__archive_write_filters_free(a);
53 	return (archive_write_add_filter_gzip(a));
54 }
55 #endif
56 
57 #ifndef HAVE_ZLIB_H
58 int
59 archive_write_add_filter_gzip(struct archive *a)
60 {
61 	archive_set_error(a, ARCHIVE_ERRNO_MISC,
62 	    "gzip compression not supported on this platform");
63 	return (ARCHIVE_FATAL);
64 }
65 #else
66 /* Don't compile this if we don't have zlib. */
67 
68 struct private_data {
69 	int		 compression_level;
70 	z_stream	 stream;
71 	int64_t		 total_in;
72 	unsigned char	*compressed;
73 	size_t		 compressed_buffer_size;
74 	unsigned long	 crc;
75 };
76 
77 /*
78  * Yuck.  zlib.h is not const-correct, so I need this one bit
79  * of ugly hackery to convert a const * pointer to a non-const pointer.
80  */
81 #define	SET_NEXT_IN(st,src)					\
82 	(st)->stream.next_in = (Bytef *)(uintptr_t)(const void *)(src)
83 
84 static int archive_compressor_gzip_options(struct archive_write_filter *,
85 		    const char *, const char *);
86 static int archive_compressor_gzip_open(struct archive_write_filter *);
87 static int archive_compressor_gzip_write(struct archive_write_filter *,
88 		    const void *, size_t);
89 static int archive_compressor_gzip_close(struct archive_write_filter *);
90 static int archive_compressor_gzip_free(struct archive_write_filter *);
91 static int drive_compressor(struct archive_write_filter *,
92 		    struct private_data *, int finishing);
93 
94 
95 /*
96  * Add a gzip compression filter to this write handle.
97  */
98 int
99 archive_write_add_filter_gzip(struct archive *_a)
100 {
101 	struct archive_write *a = (struct archive_write *)_a;
102 	struct archive_write_filter *f = __archive_write_allocate_filter(_a);
103 	struct private_data *data;
104 	archive_check_magic(&a->archive, ARCHIVE_WRITE_MAGIC,
105 	    ARCHIVE_STATE_NEW, "archive_write_add_filter_gzip");
106 
107 	data = calloc(1, sizeof(*data));
108 	if (data == NULL) {
109 		archive_set_error(&a->archive, ENOMEM, "Out of memory");
110 		return (ARCHIVE_FATAL);
111 	}
112 	f->data = data;
113 	data->compression_level = Z_DEFAULT_COMPRESSION;
114 	f->open = &archive_compressor_gzip_open;
115 	f->options = &archive_compressor_gzip_options;
116 	f->close = &archive_compressor_gzip_close;
117 	f->free = &archive_compressor_gzip_free;
118 	f->code = ARCHIVE_COMPRESSION_GZIP;
119 	f->name = "gzip";
120 	return (ARCHIVE_OK);
121 }
122 
123 /*
124  * Setup callback.
125  */
126 static int
127 archive_compressor_gzip_open(struct archive_write_filter *f)
128 {
129 	struct private_data *data = (struct private_data *)f->data;
130 	int ret;
131 	time_t t;
132 
133 	ret = __archive_write_open_filter(f->next_filter);
134 	if (ret != ARCHIVE_OK)
135 		return (ret);
136 
137 	if (data->compressed == NULL) {
138 		data->compressed_buffer_size = 65536;
139 		data->compressed
140 		    = (unsigned char *)malloc(data->compressed_buffer_size);
141 		if (data->compressed == NULL) {
142 			archive_set_error(f->archive, ENOMEM,
143 			    "Can't allocate data for compression buffer");
144 			return (ARCHIVE_FATAL);
145 		}
146 	}
147 
148 	data->crc = crc32(0L, NULL, 0);
149 	data->stream.next_out = data->compressed;
150 	data->stream.avail_out = data->compressed_buffer_size;
151 
152 	/* Prime output buffer with a gzip header. */
153 	t = time(NULL);
154 	data->compressed[0] = 0x1f; /* GZip signature bytes */
155 	data->compressed[1] = 0x8b;
156 	data->compressed[2] = 0x08; /* "Deflate" compression */
157 	data->compressed[3] = 0; /* No options */
158 	data->compressed[4] = (t)&0xff;  /* Timestamp */
159 	data->compressed[5] = (t>>8)&0xff;
160 	data->compressed[6] = (t>>16)&0xff;
161 	data->compressed[7] = (t>>24)&0xff;
162 	data->compressed[8] = 0; /* No deflate options */
163 	data->compressed[9] = 3; /* OS=Unix */
164 	data->stream.next_out += 10;
165 	data->stream.avail_out -= 10;
166 
167 	f->write = archive_compressor_gzip_write;
168 
169 	/* Initialize compression library. */
170 	ret = deflateInit2(&(data->stream),
171 	    data->compression_level,
172 	    Z_DEFLATED,
173 	    -15 /* < 0 to suppress zlib header */,
174 	    8,
175 	    Z_DEFAULT_STRATEGY);
176 
177 	if (ret == Z_OK) {
178 		f->data = data;
179 		return (ARCHIVE_OK);
180 	}
181 
182 	/* Library setup failed: clean up. */
183 	archive_set_error(f->archive, ARCHIVE_ERRNO_MISC, "Internal error "
184 	    "initializing compression library");
185 
186 	/* Override the error message if we know what really went wrong. */
187 	switch (ret) {
188 	case Z_STREAM_ERROR:
189 		archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
190 		    "Internal error initializing "
191 		    "compression library: invalid setup parameter");
192 		break;
193 	case Z_MEM_ERROR:
194 		archive_set_error(f->archive, ENOMEM, "Internal error initializing "
195 		    "compression library");
196 		break;
197 	case Z_VERSION_ERROR:
198 		archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
199 		    "Internal error initializing "
200 		    "compression library: invalid library version");
201 		break;
202 	}
203 
204 	return (ARCHIVE_FATAL);
205 }
206 
207 /*
208  * Set write options.
209  */
210 static int
211 archive_compressor_gzip_options(struct archive_write_filter *f, const char *key,
212     const char *value)
213 {
214 	struct private_data *data = (struct private_data *)f->data;
215 
216 	if (strcmp(key, "compression-level") == 0) {
217 		if (value == NULL || !(value[0] >= '0' && value[0] <= '9') ||
218 		    value[1] != '\0')
219 			return (ARCHIVE_WARN);
220 		data->compression_level = value[0] - '0';
221 		return (ARCHIVE_OK);
222 	}
223 	return (ARCHIVE_WARN);
224 }
225 
226 /*
227  * Write data to the compressed stream.
228  */
229 static int
230 archive_compressor_gzip_write(struct archive_write_filter *f, const void *buff,
231     size_t length)
232 {
233 	struct private_data *data = (struct private_data *)f->data;
234 	int ret;
235 
236 	/* Update statistics */
237 	data->crc = crc32(data->crc, (const Bytef *)buff, length);
238 	data->total_in += length;
239 
240 	/* Compress input data to output buffer */
241 	SET_NEXT_IN(data, buff);
242 	data->stream.avail_in = length;
243 	if ((ret = drive_compressor(f, data, 0)) != ARCHIVE_OK)
244 		return (ret);
245 
246 	return (ARCHIVE_OK);
247 }
248 
249 /*
250  * Finish the compression...
251  */
252 static int
253 archive_compressor_gzip_close(struct archive_write_filter *f)
254 {
255 	unsigned char trailer[8];
256 	struct private_data *data = (struct private_data *)f->data;
257 	int ret, r1;
258 
259 	/* Finish compression cycle */
260 	ret = drive_compressor(f, data, 1);
261 	if (ret == ARCHIVE_OK) {
262 		/* Write the last compressed data. */
263 		ret = __archive_write_filter(f->next_filter,
264 		    data->compressed,
265 		    data->compressed_buffer_size - data->stream.avail_out);
266 	}
267 	if (ret == ARCHIVE_OK) {
268 		/* Build and write out 8-byte trailer. */
269 		trailer[0] = (data->crc)&0xff;
270 		trailer[1] = (data->crc >> 8)&0xff;
271 		trailer[2] = (data->crc >> 16)&0xff;
272 		trailer[3] = (data->crc >> 24)&0xff;
273 		trailer[4] = (data->total_in)&0xff;
274 		trailer[5] = (data->total_in >> 8)&0xff;
275 		trailer[6] = (data->total_in >> 16)&0xff;
276 		trailer[7] = (data->total_in >> 24)&0xff;
277 		ret = __archive_write_filter(f->next_filter, trailer, 8);
278 	}
279 
280 	switch (deflateEnd(&(data->stream))) {
281 	case Z_OK:
282 		break;
283 	default:
284 		archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
285 		    "Failed to clean up compressor");
286 		ret = ARCHIVE_FATAL;
287 	}
288 	r1 = __archive_write_close_filter(f->next_filter);
289 	return (r1 < ret ? r1 : ret);
290 }
291 
292 static int
293 archive_compressor_gzip_free(struct archive_write_filter *f)
294 {
295 	struct private_data *data = (struct private_data *)f->data;
296 	free(data->compressed);
297 	free(data);
298 	f->data = NULL;
299 	return (ARCHIVE_OK);
300 }
301 
302 /*
303  * Utility function to push input data through compressor,
304  * writing full output blocks as necessary.
305  *
306  * Note that this handles both the regular write case (finishing ==
307  * false) and the end-of-archive case (finishing == true).
308  */
309 static int
310 drive_compressor(struct archive_write_filter *f,
311     struct private_data *data, int finishing)
312 {
313 	int ret;
314 
315 	for (;;) {
316 		if (data->stream.avail_out == 0) {
317 			ret = __archive_write_filter(f->next_filter,
318 			    data->compressed,
319 			    data->compressed_buffer_size);
320 			if (ret != ARCHIVE_OK)
321 				return (ARCHIVE_FATAL);
322 			data->stream.next_out = data->compressed;
323 			data->stream.avail_out = data->compressed_buffer_size;
324 		}
325 
326 		/* If there's nothing to do, we're done. */
327 		if (!finishing && data->stream.avail_in == 0)
328 			return (ARCHIVE_OK);
329 
330 		ret = deflate(&(data->stream),
331 		    finishing ? Z_FINISH : Z_NO_FLUSH );
332 
333 		switch (ret) {
334 		case Z_OK:
335 			/* In non-finishing case, check if compressor
336 			 * consumed everything */
337 			if (!finishing && data->stream.avail_in == 0)
338 				return (ARCHIVE_OK);
339 			/* In finishing case, this return always means
340 			 * there's more work */
341 			break;
342 		case Z_STREAM_END:
343 			/* This return can only occur in finishing case. */
344 			return (ARCHIVE_OK);
345 		default:
346 			/* Any other return value indicates an error. */
347 			archive_set_error(f->archive, ARCHIVE_ERRNO_MISC,
348 			    "GZip compression failed:"
349 			    " deflate() call returned status %d",
350 			    ret);
351 			return (ARCHIVE_FATAL);
352 		}
353 	}
354 }
355 
356 #endif /* HAVE_ZLIB_H */
357