xref: /freebsd/contrib/libarchive/libarchive/archive_write_set_format_ustar.c (revision b1879975794772ee51f0b4865753364c7d7626c3)
1 /*-
2  * Copyright (c) 2003-2007 Tim Kientzle
3  * Copyright (c) 2011-2012 Michihiro NAKAJIMA
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "archive_platform.h"
28 
29 #ifdef HAVE_ERRNO_H
30 #include <errno.h>
31 #endif
32 #include <stdio.h>
33 #ifdef HAVE_STDLIB_H
34 #include <stdlib.h>
35 #endif
36 #ifdef HAVE_STRING_H
37 #include <string.h>
38 #endif
39 
40 #include "archive.h"
41 #include "archive_entry.h"
42 #include "archive_entry_locale.h"
43 #include "archive_private.h"
44 #include "archive_write_private.h"
45 #include "archive_write_set_format_private.h"
46 
47 struct ustar {
48 	uint64_t	entry_bytes_remaining;
49 	uint64_t	entry_padding;
50 
51 	struct archive_string_conv *opt_sconv;
52 	struct archive_string_conv *sconv_default;
53 	int	init_default_conversion;
54 };
55 
56 /*
57  * Define structure of POSIX 'ustar' tar header.
58  */
59 #define	USTAR_name_offset 0
60 #define	USTAR_name_size 100
61 #define	USTAR_mode_offset 100
62 #define	USTAR_mode_size 6
63 #define	USTAR_mode_max_size 8
64 #define	USTAR_uid_offset 108
65 #define	USTAR_uid_size 6
66 #define	USTAR_uid_max_size 8
67 #define	USTAR_gid_offset 116
68 #define	USTAR_gid_size 6
69 #define	USTAR_gid_max_size 8
70 #define	USTAR_size_offset 124
71 #define	USTAR_size_size 11
72 #define	USTAR_size_max_size 12
73 #define	USTAR_mtime_offset 136
74 #define	USTAR_mtime_size 11
75 #define	USTAR_mtime_max_size 11
76 #define	USTAR_checksum_offset 148
77 #define	USTAR_checksum_size 8
78 #define	USTAR_typeflag_offset 156
79 #define	USTAR_typeflag_size 1
80 #define	USTAR_linkname_offset 157
81 #define	USTAR_linkname_size 100
82 #define	USTAR_magic_offset 257
83 #define	USTAR_magic_size 6
84 #define	USTAR_version_offset 263
85 #define	USTAR_version_size 2
86 #define	USTAR_uname_offset 265
87 #define	USTAR_uname_size 32
88 #define	USTAR_gname_offset 297
89 #define	USTAR_gname_size 32
90 #define	USTAR_rdevmajor_offset 329
91 #define	USTAR_rdevmajor_size 6
92 #define	USTAR_rdevmajor_max_size 8
93 #define	USTAR_rdevminor_offset 337
94 #define	USTAR_rdevminor_size 6
95 #define	USTAR_rdevminor_max_size 8
96 #define	USTAR_prefix_offset 345
97 #define	USTAR_prefix_size 155
98 #define	USTAR_padding_offset 500
99 #define	USTAR_padding_size 12
100 
101 /*
102  * A filled-in copy of the header for initialization.
103  */
104 static const char template_header[] = {
105 	/* name: 100 bytes */
106 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
107 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
108 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
109 	0,0,0,0,
110 	/* Mode, space-null termination: 8 bytes */
111 	'0','0','0','0','0','0', ' ','\0',
112 	/* uid, space-null termination: 8 bytes */
113 	'0','0','0','0','0','0', ' ','\0',
114 	/* gid, space-null termination: 8 bytes */
115 	'0','0','0','0','0','0', ' ','\0',
116 	/* size, space termination: 12 bytes */
117 	'0','0','0','0','0','0','0','0','0','0','0', ' ',
118 	/* mtime, space termination: 12 bytes */
119 	'0','0','0','0','0','0','0','0','0','0','0', ' ',
120 	/* Initial checksum value: 8 spaces */
121 	' ',' ',' ',' ',' ',' ',' ',' ',
122 	/* Typeflag: 1 byte */
123 	'0',			/* '0' = regular file */
124 	/* Linkname: 100 bytes */
125 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
126 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
127 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
128 	0,0,0,0,
129 	/* Magic: 6 bytes, Version: 2 bytes */
130 	'u','s','t','a','r','\0', '0','0',
131 	/* Uname: 32 bytes */
132 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
133 	/* Gname: 32 bytes */
134 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
135 	/* rdevmajor + space/null padding: 8 bytes */
136 	'0','0','0','0','0','0', ' ','\0',
137 	/* rdevminor + space/null padding: 8 bytes */
138 	'0','0','0','0','0','0', ' ','\0',
139 	/* Prefix: 155 bytes */
140 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
141 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
142 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
143 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,
144 	0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, 0,0,0,
145 	/* Padding: 12 bytes */
146 	0,0,0,0,0,0,0,0, 0,0,0,0
147 };
148 
149 static ssize_t	archive_write_ustar_data(struct archive_write *a, const void *buff,
150 		    size_t s);
151 static int	archive_write_ustar_free(struct archive_write *);
152 static int	archive_write_ustar_close(struct archive_write *);
153 static int	archive_write_ustar_finish_entry(struct archive_write *);
154 static int	archive_write_ustar_header(struct archive_write *,
155 		    struct archive_entry *entry);
156 static int	archive_write_ustar_options(struct archive_write *,
157 		    const char *, const char *);
158 static int	format_256(int64_t, char *, int);
159 static int	format_number(int64_t, char *, int size, int max, int strict);
160 static int	format_octal(int64_t, char *, int);
161 
162 /*
163  * Set output format to 'ustar' format.
164  */
165 int
166 archive_write_set_format_ustar(struct archive *_a)
167 {
168 	struct archive_write *a = (struct archive_write *)_a;
169 	struct ustar *ustar;
170 
171 	archive_check_magic(_a, ARCHIVE_WRITE_MAGIC,
172 	    ARCHIVE_STATE_NEW, "archive_write_set_format_ustar");
173 
174 	/* If someone else was already registered, unregister them. */
175 	if (a->format_free != NULL)
176 		(a->format_free)(a);
177 
178 	/* Basic internal sanity test. */
179 	if (sizeof(template_header) != 512) {
180 		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
181 		    "Internal: template_header wrong size: %zu should be 512",
182 		    sizeof(template_header));
183 		return (ARCHIVE_FATAL);
184 	}
185 
186 	ustar = calloc(1, sizeof(*ustar));
187 	if (ustar == NULL) {
188 		archive_set_error(&a->archive, ENOMEM,
189 		    "Can't allocate ustar data");
190 		return (ARCHIVE_FATAL);
191 	}
192 	a->format_data = ustar;
193 	a->format_name = "ustar";
194 	a->format_options = archive_write_ustar_options;
195 	a->format_write_header = archive_write_ustar_header;
196 	a->format_write_data = archive_write_ustar_data;
197 	a->format_close = archive_write_ustar_close;
198 	a->format_free = archive_write_ustar_free;
199 	a->format_finish_entry = archive_write_ustar_finish_entry;
200 	a->archive.archive_format = ARCHIVE_FORMAT_TAR_USTAR;
201 	a->archive.archive_format_name = "POSIX ustar";
202 	return (ARCHIVE_OK);
203 }
204 
205 static int
206 archive_write_ustar_options(struct archive_write *a, const char *key,
207     const char *val)
208 {
209 	struct ustar *ustar = (struct ustar *)a->format_data;
210 	int ret = ARCHIVE_FAILED;
211 
212 	if (strcmp(key, "hdrcharset")  == 0) {
213 		if (val == NULL || val[0] == 0)
214 			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
215 			    "%s: hdrcharset option needs a character-set name",
216 			    a->format_name);
217 		else {
218 			ustar->opt_sconv = archive_string_conversion_to_charset(
219 			    &a->archive, val, 0);
220 			if (ustar->opt_sconv != NULL)
221 				ret = ARCHIVE_OK;
222 			else
223 				ret = ARCHIVE_FATAL;
224 		}
225 		return (ret);
226 	}
227 
228 	/* Note: The "warn" return is just to inform the options
229 	 * supervisor that we didn't handle it.  It will generate
230 	 * a suitable error if no one used this option. */
231 	return (ARCHIVE_WARN);
232 }
233 
234 static int
235 archive_write_ustar_header(struct archive_write *a, struct archive_entry *entry)
236 {
237 	char buff[512];
238 	int ret, ret2;
239 	struct ustar *ustar;
240 	struct archive_entry *entry_main;
241 	struct archive_string_conv *sconv;
242 
243 	ustar = (struct ustar *)a->format_data;
244 
245 	/* Setup default string conversion. */
246 	if (ustar->opt_sconv == NULL) {
247 		if (!ustar->init_default_conversion) {
248 			ustar->sconv_default =
249 			    archive_string_default_conversion_for_write(&(a->archive));
250 			ustar->init_default_conversion = 1;
251 		}
252 		sconv = ustar->sconv_default;
253 	} else
254 		sconv = ustar->opt_sconv;
255 
256 	/* Sanity check. */
257 #if defined(_WIN32) && !defined(__CYGWIN__)
258 	if (archive_entry_pathname_w(entry) == NULL) {
259 #else
260 	if (archive_entry_pathname(entry) == NULL) {
261 #endif
262 		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
263 		    "Can't record entry in tar file without pathname");
264 		return (ARCHIVE_FAILED);
265 	}
266 
267 	/* Only regular files (not hardlinks) have data. */
268 	if (archive_entry_hardlink(entry) != NULL ||
269 	    archive_entry_symlink(entry) != NULL ||
270 	    archive_entry_filetype(entry) != AE_IFREG)
271 		archive_entry_set_size(entry, 0);
272 
273 	if (AE_IFDIR == archive_entry_filetype(entry)) {
274 		const char *p;
275 		size_t path_length;
276 		/*
277 		 * Ensure a trailing '/'.  Modify the entry so
278 		 * the client sees the change.
279 		 */
280 #if defined(_WIN32) && !defined(__CYGWIN__)
281 		const wchar_t *wp;
282 
283 		wp = archive_entry_pathname_w(entry);
284 		if (wp != NULL && wp[wcslen(wp) -1] != L'/') {
285 			struct archive_wstring ws;
286 
287 			archive_string_init(&ws);
288 			path_length = wcslen(wp);
289 			if (archive_wstring_ensure(&ws,
290 			    path_length + 2) == NULL) {
291 				archive_set_error(&a->archive, ENOMEM,
292 				    "Can't allocate ustar data");
293 				archive_wstring_free(&ws);
294 				return(ARCHIVE_FATAL);
295 			}
296 			/* Should we keep '\' ? */
297 			if (wp[path_length -1] == L'\\')
298 				path_length--;
299 			archive_wstrncpy(&ws, wp, path_length);
300 			archive_wstrappend_wchar(&ws, L'/');
301 			archive_entry_copy_pathname_w(entry, ws.s);
302 			archive_wstring_free(&ws);
303 			p = NULL;
304 		} else
305 #endif
306 			p = archive_entry_pathname(entry);
307 		/*
308 		 * On Windows, this is a backup operation just in
309 		 * case getting WCS failed. On POSIX, this is a
310 		 * normal operation.
311 		 */
312 		if (p != NULL && p[0] != '\0' && p[strlen(p) - 1] != '/') {
313 			struct archive_string as;
314 
315 			archive_string_init(&as);
316 			path_length = strlen(p);
317 			if (archive_string_ensure(&as,
318 			    path_length + 2) == NULL) {
319 				archive_set_error(&a->archive, ENOMEM,
320 				    "Can't allocate ustar data");
321 				archive_string_free(&as);
322 				return(ARCHIVE_FATAL);
323 			}
324 #if defined(_WIN32) && !defined(__CYGWIN__)
325 			/* NOTE: This might break the pathname
326 			 * if the current code page is CP932 and
327 			 * the pathname includes a character '\'
328 			 * as a part of its multibyte pathname. */
329 			if (p[strlen(p) -1] == '\\')
330 				path_length--;
331 			else
332 #endif
333 			archive_strncpy(&as, p, path_length);
334 			archive_strappend_char(&as, '/');
335 			archive_entry_copy_pathname(entry, as.s);
336 			archive_string_free(&as);
337 		}
338 	}
339 
340 #if defined(_WIN32) && !defined(__CYGWIN__)
341 	/* Make sure the path separators in pathname, hardlink and symlink
342 	 * are all slash '/', not the Windows path separator '\'. */
343 	entry_main = __la_win_entry_in_posix_pathseparator(entry);
344 	if (entry_main == NULL) {
345 		archive_set_error(&a->archive, ENOMEM,
346 		    "Can't allocate ustar data");
347 		return(ARCHIVE_FATAL);
348 	}
349 	if (entry != entry_main)
350 		entry = entry_main;
351 	else
352 		entry_main = NULL;
353 #else
354 	entry_main = NULL;
355 #endif
356 	ret = __archive_write_format_header_ustar(a, buff, entry, -1, 1, sconv);
357 	if (ret < ARCHIVE_WARN) {
358 		archive_entry_free(entry_main);
359 		return (ret);
360 	}
361 	ret2 = __archive_write_output(a, buff, 512);
362 	if (ret2 < ARCHIVE_WARN) {
363 		archive_entry_free(entry_main);
364 		return (ret2);
365 	}
366 	if (ret2 < ret)
367 		ret = ret2;
368 
369 	ustar->entry_bytes_remaining = archive_entry_size(entry);
370 	ustar->entry_padding = 0x1ff & (-(int64_t)ustar->entry_bytes_remaining);
371 	archive_entry_free(entry_main);
372 	return (ret);
373 }
374 
375 /*
376  * Format a basic 512-byte "ustar" header.
377  *
378  * Returns -1 if format failed (due to field overflow).
379  * Note that this always formats as much of the header as possible.
380  * If "strict" is set to zero, it will extend numeric fields as
381  * necessary (overwriting terminators or using base-256 extensions).
382  *
383  * This is exported so that other 'tar' formats can use it.
384  */
385 int
386 __archive_write_format_header_ustar(struct archive_write *a, char h[512],
387     struct archive_entry *entry, int tartype, int strict,
388     struct archive_string_conv *sconv)
389 {
390 	unsigned int checksum;
391 	int i, r, ret;
392 	size_t copy_length;
393 	const char *p, *pp;
394 	int mytartype;
395 
396 	ret = 0;
397 	mytartype = -1;
398 	/*
399 	 * The "template header" already includes the "ustar"
400 	 * signature, various end-of-field markers and other required
401 	 * elements.
402 	 */
403 	memcpy(h, &template_header, 512);
404 
405 	/*
406 	 * Because the block is already null-filled, and strings
407 	 * are allowed to exactly fill their destination (without null),
408 	 * I use memcpy(dest, src, strlen()) here a lot to copy strings.
409 	 */
410 	r = archive_entry_pathname_l(entry, &pp, &copy_length, sconv);
411 	if (r != 0) {
412 		if (errno == ENOMEM) {
413 			archive_set_error(&a->archive, ENOMEM,
414 			    "Can't allocate memory for Pathname");
415 			return (ARCHIVE_FATAL);
416 		}
417 		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
418 		    "Can't translate pathname '%s' to %s",
419 		    pp, archive_string_conversion_charset_name(sconv));
420 		ret = ARCHIVE_WARN;
421 	}
422 	if (copy_length <= USTAR_name_size)
423 		memcpy(h + USTAR_name_offset, pp, copy_length);
424 	else {
425 		/* Store in two pieces, splitting at a '/'. */
426 		p = strchr(pp + copy_length - USTAR_name_size - 1, '/');
427 		/*
428 		 * Look for the next '/' if we chose the first character
429 		 * as the separator.  (ustar format doesn't permit
430 		 * an empty prefix.)
431 		 */
432 		if (p == pp)
433 			p = strchr(p + 1, '/');
434 		/* Fail if the name won't fit. */
435 		if (!p) {
436 			/* No separator. */
437 			archive_set_error(&a->archive, ENAMETOOLONG,
438 			    "Pathname too long");
439 			ret = ARCHIVE_FAILED;
440 		} else if (p[1] == '\0') {
441 			/*
442 			 * The only feasible separator is a final '/';
443 			 * this would result in a non-empty prefix and
444 			 * an empty name, which POSIX doesn't
445 			 * explicitly forbid, but it just feels wrong.
446 			 */
447 			archive_set_error(&a->archive, ENAMETOOLONG,
448 			    "Pathname too long");
449 			ret = ARCHIVE_FAILED;
450 		} else if (p  > pp + USTAR_prefix_size) {
451 			/* Prefix is too long. */
452 			archive_set_error(&a->archive, ENAMETOOLONG,
453 			    "Pathname too long");
454 			ret = ARCHIVE_FAILED;
455 		} else {
456 			/* Copy prefix and remainder to appropriate places */
457 			memcpy(h + USTAR_prefix_offset, pp, p - pp);
458 			memcpy(h + USTAR_name_offset, p + 1,
459 			    pp + copy_length - p - 1);
460 		}
461 	}
462 
463 	r = archive_entry_hardlink_l(entry, &p, &copy_length, sconv);
464 	if (r != 0) {
465 		if (errno == ENOMEM) {
466 			archive_set_error(&a->archive, ENOMEM,
467 			    "Can't allocate memory for Linkname");
468 			return (ARCHIVE_FATAL);
469 		}
470 		archive_set_error(&a->archive,
471 		    ARCHIVE_ERRNO_FILE_FORMAT,
472 		    "Can't translate linkname '%s' to %s",
473 		    p, archive_string_conversion_charset_name(sconv));
474 		ret = ARCHIVE_WARN;
475 	}
476 	if (copy_length > 0)
477 		mytartype = '1';
478 	else {
479 		r = archive_entry_symlink_l(entry, &p, &copy_length, sconv);
480 		if (r != 0) {
481 			if (errno == ENOMEM) {
482 				archive_set_error(&a->archive, ENOMEM,
483 				    "Can't allocate memory for Linkname");
484 				return (ARCHIVE_FATAL);
485 			}
486 			archive_set_error(&a->archive,
487 			    ARCHIVE_ERRNO_FILE_FORMAT,
488 			    "Can't translate linkname '%s' to %s",
489 			    p, archive_string_conversion_charset_name(sconv));
490 			ret = ARCHIVE_WARN;
491 		}
492 	}
493 	if (copy_length > 0) {
494 		if (copy_length > USTAR_linkname_size) {
495 			archive_set_error(&a->archive, ENAMETOOLONG,
496 			    "Link contents too long");
497 			ret = ARCHIVE_FAILED;
498 			copy_length = USTAR_linkname_size;
499 		}
500 		memcpy(h + USTAR_linkname_offset, p, copy_length);
501 	}
502 
503 	r = archive_entry_uname_l(entry, &p, &copy_length, sconv);
504 	if (r != 0) {
505 		if (errno == ENOMEM) {
506 			archive_set_error(&a->archive, ENOMEM,
507 			    "Can't allocate memory for Uname");
508 			return (ARCHIVE_FATAL);
509 		}
510 		archive_set_error(&a->archive,
511 		    ARCHIVE_ERRNO_FILE_FORMAT,
512 		    "Can't translate uname '%s' to %s",
513 		    p, archive_string_conversion_charset_name(sconv));
514 		ret = ARCHIVE_WARN;
515 	}
516 	if (copy_length > 0) {
517 		if (copy_length > USTAR_uname_size) {
518 			if (tartype != 'x') {
519 				archive_set_error(&a->archive,
520 				    ARCHIVE_ERRNO_MISC, "Username too long");
521 				ret = ARCHIVE_FAILED;
522 			}
523 			copy_length = USTAR_uname_size;
524 		}
525 		memcpy(h + USTAR_uname_offset, p, copy_length);
526 	}
527 
528 	r = archive_entry_gname_l(entry, &p, &copy_length, sconv);
529 	if (r != 0) {
530 		if (errno == ENOMEM) {
531 			archive_set_error(&a->archive, ENOMEM,
532 			    "Can't allocate memory for Gname");
533 			return (ARCHIVE_FATAL);
534 		}
535 		archive_set_error(&a->archive,
536 		    ARCHIVE_ERRNO_FILE_FORMAT,
537 		    "Can't translate gname '%s' to %s",
538 		    p, archive_string_conversion_charset_name(sconv));
539 		ret = ARCHIVE_WARN;
540 	}
541 	if (copy_length > 0) {
542 		if (strlen(p) > USTAR_gname_size) {
543 			if (tartype != 'x') {
544 				archive_set_error(&a->archive,
545 				    ARCHIVE_ERRNO_MISC, "Group name too long");
546 				ret = ARCHIVE_FAILED;
547 			}
548 			copy_length = USTAR_gname_size;
549 		}
550 		memcpy(h + USTAR_gname_offset, p, copy_length);
551 	}
552 
553 	if (format_number(archive_entry_mode(entry) & 07777,
554 	    h + USTAR_mode_offset, USTAR_mode_size, USTAR_mode_max_size, strict)) {
555 		archive_set_error(&a->archive, ERANGE,
556 		    "Numeric mode too large");
557 		ret = ARCHIVE_FAILED;
558 	}
559 
560 	if (format_number(archive_entry_uid(entry),
561 	    h + USTAR_uid_offset, USTAR_uid_size, USTAR_uid_max_size, strict)) {
562 		archive_set_error(&a->archive, ERANGE,
563 		    "Numeric user ID too large");
564 		ret = ARCHIVE_FAILED;
565 	}
566 
567 	if (format_number(archive_entry_gid(entry),
568 	    h + USTAR_gid_offset, USTAR_gid_size, USTAR_gid_max_size, strict)) {
569 		archive_set_error(&a->archive, ERANGE,
570 		    "Numeric group ID too large");
571 		ret = ARCHIVE_FAILED;
572 	}
573 
574 	if (format_number(archive_entry_size(entry),
575 	    h + USTAR_size_offset, USTAR_size_size, USTAR_size_max_size, strict)) {
576 		archive_set_error(&a->archive, ERANGE,
577 		    "File size out of range");
578 		ret = ARCHIVE_FAILED;
579 	}
580 
581 	if (format_number(archive_entry_mtime(entry),
582 	    h + USTAR_mtime_offset, USTAR_mtime_size, USTAR_mtime_max_size, strict)) {
583 		archive_set_error(&a->archive, ERANGE,
584 		    "File modification time too large");
585 		ret = ARCHIVE_FAILED;
586 	}
587 
588 	if (archive_entry_filetype(entry) == AE_IFBLK
589 	    || archive_entry_filetype(entry) == AE_IFCHR) {
590 		if (format_number(archive_entry_rdevmajor(entry),
591 		    h + USTAR_rdevmajor_offset, USTAR_rdevmajor_size,
592 		    USTAR_rdevmajor_max_size, strict)) {
593 			archive_set_error(&a->archive, ERANGE,
594 			    "Major device number too large");
595 			ret = ARCHIVE_FAILED;
596 		}
597 
598 		if (format_number(archive_entry_rdevminor(entry),
599 		    h + USTAR_rdevminor_offset, USTAR_rdevminor_size,
600 		    USTAR_rdevminor_max_size, strict)) {
601 			archive_set_error(&a->archive, ERANGE,
602 			    "Minor device number too large");
603 			ret = ARCHIVE_FAILED;
604 		}
605 	}
606 
607 	if (tartype >= 0) {
608 		h[USTAR_typeflag_offset] = tartype;
609 	} else if (mytartype >= 0) {
610 		h[USTAR_typeflag_offset] = mytartype;
611 	} else {
612 		switch (archive_entry_filetype(entry)) {
613 		case AE_IFREG: h[USTAR_typeflag_offset] = '0' ; break;
614 		case AE_IFLNK: h[USTAR_typeflag_offset] = '2' ; break;
615 		case AE_IFCHR: h[USTAR_typeflag_offset] = '3' ; break;
616 		case AE_IFBLK: h[USTAR_typeflag_offset] = '4' ; break;
617 		case AE_IFDIR: h[USTAR_typeflag_offset] = '5' ; break;
618 		case AE_IFIFO: h[USTAR_typeflag_offset] = '6' ; break;
619 		default: /* AE_IFSOCK and unknown */
620 			__archive_write_entry_filetype_unsupported(
621 			    &a->archive, entry, "ustar");
622 			ret = ARCHIVE_FAILED;
623 		}
624 	}
625 
626 	checksum = 0;
627 	for (i = 0; i < 512; i++)
628 		checksum += 255 & (unsigned int)h[i];
629 	h[USTAR_checksum_offset + 6] = '\0'; /* Can't be pre-set in the template. */
630 	/* h[USTAR_checksum_offset + 7] = ' '; */ /* This is pre-set in the template. */
631 	format_octal(checksum, h + USTAR_checksum_offset, 6);
632 	return (ret);
633 }
634 
635 /*
636  * Format a number into a field, with some intelligence.
637  */
638 static int
639 format_number(int64_t v, char *p, int s, int maxsize, int strict)
640 {
641 	int64_t limit;
642 
643 	limit = ((int64_t)1 << (s*3));
644 
645 	/* "Strict" only permits octal values with proper termination. */
646 	if (strict)
647 		return (format_octal(v, p, s));
648 
649 	/*
650 	 * In non-strict mode, we allow the number to overwrite one or
651 	 * more bytes of the field termination.  Even old tar
652 	 * implementations should be able to handle this with no
653 	 * problem.
654 	 */
655 	if (v >= 0) {
656 		while (s <= maxsize) {
657 			if (v < limit)
658 				return (format_octal(v, p, s));
659 			s++;
660 			limit <<= 3;
661 		}
662 	}
663 
664 	/* Base-256 can handle any number, positive or negative. */
665 	return (format_256(v, p, maxsize));
666 }
667 
668 /*
669  * Format a number into the specified field using base-256.
670  */
671 static int
672 format_256(int64_t v, char *p, int s)
673 {
674 	p += s;
675 	while (s-- > 0) {
676 		*--p = (char)(v & 0xff);
677 		v >>= 8;
678 	}
679 	*p |= 0x80; /* Set the base-256 marker bit. */
680 	return (0);
681 }
682 
683 /*
684  * Format a number into the specified field.
685  */
686 static int
687 format_octal(int64_t v, char *p, int s)
688 {
689 	int len;
690 
691 	len = s;
692 
693 	/* Octal values can't be negative, so use 0. */
694 	if (v < 0) {
695 		while (len-- > 0)
696 			*p++ = '0';
697 		return (-1);
698 	}
699 
700 	p += s;		/* Start at the end and work backwards. */
701 	while (s-- > 0) {
702 		*--p = (char)('0' + (v & 7));
703 		v >>= 3;
704 	}
705 
706 	if (v == 0)
707 		return (0);
708 
709 	/* If it overflowed, fill field with max value. */
710 	while (len-- > 0)
711 		*p++ = '7';
712 
713 	return (-1);
714 }
715 
716 static int
717 archive_write_ustar_close(struct archive_write *a)
718 {
719 	return (__archive_write_nulls(a, 512*2));
720 }
721 
722 static int
723 archive_write_ustar_free(struct archive_write *a)
724 {
725 	struct ustar *ustar;
726 
727 	ustar = (struct ustar *)a->format_data;
728 	free(ustar);
729 	a->format_data = NULL;
730 	return (ARCHIVE_OK);
731 }
732 
733 static int
734 archive_write_ustar_finish_entry(struct archive_write *a)
735 {
736 	struct ustar *ustar;
737 	int ret;
738 
739 	ustar = (struct ustar *)a->format_data;
740 	ret = __archive_write_nulls(a,
741 	    (size_t)(ustar->entry_bytes_remaining + ustar->entry_padding));
742 	ustar->entry_bytes_remaining = ustar->entry_padding = 0;
743 	return (ret);
744 }
745 
746 static ssize_t
747 archive_write_ustar_data(struct archive_write *a, const void *buff, size_t s)
748 {
749 	struct ustar *ustar;
750 	int ret;
751 
752 	ustar = (struct ustar *)a->format_data;
753 	if (s > ustar->entry_bytes_remaining)
754 		s = (size_t)ustar->entry_bytes_remaining;
755 	ret = __archive_write_output(a, buff, s);
756 	ustar->entry_bytes_remaining -= s;
757 	if (ret != ARCHIVE_OK)
758 		return (ret);
759 	return (s);
760 }
761