xref: /freebsd/contrib/libarchive/libarchive/archive_write_set_format_gnutar.c (revision eb5165bb491138f60d9004bc4c781490016d9288)
1 /*-
2  * Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
3  * Author: Jonas Gastal <jgastal@profusion.mobi>
4  * Copyright (c) 2011-2012 Michihiro NAKAJIMA
5  *
6  * All rights reserved.
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 the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include "archive_platform.h"
30 
31 #ifdef HAVE_ERRNO_H
32 #include <errno.h>
33 #endif
34 #include <stdio.h>
35 #ifdef HAVE_STDLIB_H
36 #include <stdlib.h>
37 #endif
38 #ifdef HAVE_STRING_H
39 #include <string.h>
40 #endif
41 
42 #include "archive.h"
43 #include "archive_entry.h"
44 #include "archive_entry_locale.h"
45 #include "archive_private.h"
46 #include "archive_write_private.h"
47 #include "archive_write_set_format_private.h"
48 
49 struct gnutar {
50 	uint64_t	entry_bytes_remaining;
51 	uint64_t	entry_padding;
52 	const char *	linkname;
53 	size_t		linkname_length;
54 	const char *	pathname;
55 	size_t		pathname_length;
56 	const char *	uname;
57 	size_t		uname_length;
58 	const char *	gname;
59 	size_t		gname_length;
60 	struct archive_string_conv *opt_sconv;
61 	struct archive_string_conv *sconv_default;
62 	int init_default_conversion;
63 };
64 
65 /*
66  * Define structure of GNU tar header.
67  */
68 #define	GNUTAR_name_offset 0
69 #define	GNUTAR_name_size 100
70 #define	GNUTAR_mode_offset 100
71 #define	GNUTAR_mode_size 7
72 #define	GNUTAR_mode_max_size 8
73 #define	GNUTAR_uid_offset 108
74 #define	GNUTAR_uid_size 7
75 #define	GNUTAR_uid_max_size 8
76 #define	GNUTAR_gid_offset 116
77 #define	GNUTAR_gid_size 7
78 #define	GNUTAR_gid_max_size 8
79 #define	GNUTAR_size_offset 124
80 #define	GNUTAR_size_size 11
81 #define	GNUTAR_size_max_size 12
82 #define	GNUTAR_mtime_offset 136
83 #define	GNUTAR_mtime_size 11
84 #define	GNUTAR_mtime_max_size 11
85 #define	GNUTAR_checksum_offset 148
86 #define	GNUTAR_checksum_size 8
87 #define	GNUTAR_typeflag_offset 156
88 #define	GNUTAR_typeflag_size 1
89 #define	GNUTAR_linkname_offset 157
90 #define	GNUTAR_linkname_size 100
91 #define	GNUTAR_magic_offset 257
92 #define	GNUTAR_magic_size 6
93 #define	GNUTAR_version_offset 263
94 #define	GNUTAR_version_size 2
95 #define	GNUTAR_uname_offset 265
96 #define	GNUTAR_uname_size 32
97 #define	GNUTAR_gname_offset 297
98 #define	GNUTAR_gname_size 32
99 #define	GNUTAR_rdevmajor_offset 329
100 #define	GNUTAR_rdevmajor_size 6
101 #define	GNUTAR_rdevmajor_max_size 8
102 #define	GNUTAR_rdevminor_offset 337
103 #define	GNUTAR_rdevminor_size 6
104 #define	GNUTAR_rdevminor_max_size 8
105 
106 /*
107  * A filled-in copy of the header for initialization.
108  */
109 static const char template_header[] = {
110 	/* name: 100 bytes */
111 	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,
112 	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,
113 	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,
114 	0,0,0,0,
115 	/* Mode, null termination: 8 bytes */
116 	'0','0','0','0','0','0', '0','\0',
117 	/* uid, null termination: 8 bytes */
118 	'0','0','0','0','0','0', '0','\0',
119 	/* gid, null termination: 8 bytes */
120 	'0','0','0','0','0','0', '0','\0',
121 	/* size, space termination: 12 bytes */
122 	'0','0','0','0','0','0','0','0','0','0','0', '\0',
123 	/* mtime, space termination: 12 bytes */
124 	'0','0','0','0','0','0','0','0','0','0','0', '\0',
125 	/* Initial checksum value: 8 spaces */
126 	' ',' ',' ',' ',' ',' ',' ',' ',
127 	/* Typeflag: 1 byte */
128 	'0',			/* '0' = regular file */
129 	/* Linkname: 100 bytes */
130 	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,
131 	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,
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 	0,0,0,0,
134 	/* Magic: 8 bytes */
135 	'u','s','t','a','r',' ', ' ','\0',
136 	/* Uname: 32 bytes */
137 	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,
138 	/* Gname: 32 bytes */
139 	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,
140 	/* rdevmajor + null padding: 8 bytes */
141 	'\0','\0','\0','\0','\0','\0', '\0','\0',
142 	/* rdevminor + null padding: 8 bytes */
143 	'\0','\0','\0','\0','\0','\0', '\0','\0',
144 	/* Padding: 167 bytes */
145 	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,
146 	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,
147 	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,
148 	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,
149 	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,
150 	0,0,0,0,0,0,0
151 };
152 
153 static int      archive_write_gnutar_options(struct archive_write *,
154 		    const char *, const char *);
155 static int	archive_format_gnutar_header(struct archive_write *, char h[512],
156 		    struct archive_entry *, char tartype);
157 static int      archive_write_gnutar_header(struct archive_write *,
158 		    struct archive_entry *entry);
159 static ssize_t	archive_write_gnutar_data(struct archive_write *a, const void *buff,
160 		    size_t s);
161 static int	archive_write_gnutar_free(struct archive_write *);
162 static int	archive_write_gnutar_close(struct archive_write *);
163 static int	archive_write_gnutar_finish_entry(struct archive_write *);
164 static int	format_256(int64_t, char *, int);
165 static int	format_number(int64_t, char *, int size, int maxsize);
166 static int	format_octal(int64_t, char *, int);
167 
168 /*
169  * Set output format to 'GNU tar' format.
170  */
171 int
archive_write_set_format_gnutar(struct archive * _a)172 archive_write_set_format_gnutar(struct archive *_a)
173 {
174 	struct archive_write *a = (struct archive_write *)_a;
175 	struct gnutar *gnutar;
176 
177 	gnutar = calloc(1, sizeof(*gnutar));
178 	if (gnutar == NULL) {
179 		archive_set_error(&a->archive, ENOMEM,
180 		    "Can't allocate gnutar data");
181 		return (ARCHIVE_FATAL);
182 	}
183 	a->format_data = gnutar;
184 	a->format_name = "gnutar";
185 	a->format_options = archive_write_gnutar_options;
186 	a->format_write_header = archive_write_gnutar_header;
187 	a->format_write_data = archive_write_gnutar_data;
188 	a->format_close = archive_write_gnutar_close;
189 	a->format_free = archive_write_gnutar_free;
190 	a->format_finish_entry = archive_write_gnutar_finish_entry;
191 	a->archive.archive_format = ARCHIVE_FORMAT_TAR_GNUTAR;
192 	a->archive.archive_format_name = "GNU tar";
193 	return (ARCHIVE_OK);
194 }
195 
196 static int
archive_write_gnutar_options(struct archive_write * a,const char * key,const char * val)197 archive_write_gnutar_options(struct archive_write *a, const char *key,
198     const char *val)
199 {
200 	struct gnutar *gnutar = (struct gnutar *)a->format_data;
201 	int ret = ARCHIVE_FAILED;
202 
203 	if (strcmp(key, "hdrcharset")  == 0) {
204 		if (val == NULL || val[0] == 0)
205 			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
206 			    "%s: hdrcharset option needs a character-set name",
207 			    a->format_name);
208 		else {
209 			gnutar->opt_sconv = archive_string_conversion_to_charset(
210 			    &a->archive, val, 0);
211 			if (gnutar->opt_sconv != NULL)
212 				ret = ARCHIVE_OK;
213 			else
214 				ret = ARCHIVE_FATAL;
215 		}
216 		return (ret);
217 	}
218 
219 	/* Note: The "warn" return is just to inform the options
220 	 * supervisor that we didn't handle it.  It will generate
221 	 * a suitable error if no one used this option. */
222 	return (ARCHIVE_WARN);
223 }
224 
225 static int
archive_write_gnutar_close(struct archive_write * a)226 archive_write_gnutar_close(struct archive_write *a)
227 {
228 	return (__archive_write_nulls(a, 512*2));
229 }
230 
231 static int
archive_write_gnutar_free(struct archive_write * a)232 archive_write_gnutar_free(struct archive_write *a)
233 {
234 	struct gnutar *gnutar;
235 
236 	gnutar = (struct gnutar *)a->format_data;
237 	free(gnutar);
238 	a->format_data = NULL;
239 	return (ARCHIVE_OK);
240 }
241 
242 static int
archive_write_gnutar_finish_entry(struct archive_write * a)243 archive_write_gnutar_finish_entry(struct archive_write *a)
244 {
245 	struct gnutar *gnutar;
246 	int ret;
247 
248 	gnutar = (struct gnutar *)a->format_data;
249 	ret = __archive_write_nulls(a, (size_t)
250 	    (gnutar->entry_bytes_remaining + gnutar->entry_padding));
251 	gnutar->entry_bytes_remaining = gnutar->entry_padding = 0;
252 	return (ret);
253 }
254 
255 static ssize_t
archive_write_gnutar_data(struct archive_write * a,const void * buff,size_t s)256 archive_write_gnutar_data(struct archive_write *a, const void *buff, size_t s)
257 {
258 	struct gnutar *gnutar;
259 	int ret;
260 
261 	gnutar = (struct gnutar *)a->format_data;
262 	if (s > gnutar->entry_bytes_remaining)
263 		s = (size_t)gnutar->entry_bytes_remaining;
264 	ret = __archive_write_output(a, buff, s);
265 	gnutar->entry_bytes_remaining -= s;
266 	if (ret != ARCHIVE_OK)
267 		return (ret);
268 	return (s);
269 }
270 
271 static int
archive_write_gnutar_header(struct archive_write * a,struct archive_entry * entry)272 archive_write_gnutar_header(struct archive_write *a,
273      struct archive_entry *entry)
274 {
275 	char buff[512];
276 	int r, ret, ret2 = ARCHIVE_OK;
277 	char tartype;
278 	struct gnutar *gnutar;
279 	struct archive_string_conv *sconv;
280 	struct archive_entry *entry_main;
281 
282 	gnutar = (struct gnutar *)a->format_data;
283 
284 	/* Setup default string conversion. */
285 	if (gnutar->opt_sconv == NULL) {
286 		if (!gnutar->init_default_conversion) {
287 			gnutar->sconv_default =
288 			    archive_string_default_conversion_for_write(
289 				&(a->archive));
290 			gnutar->init_default_conversion = 1;
291 		}
292 		sconv = gnutar->sconv_default;
293 	} else
294 		sconv = gnutar->opt_sconv;
295 
296 	/* Sanity check. */
297 	if (archive_entry_pathname(entry) == NULL
298 #if defined(_WIN32) && !defined(__CYGWIN__)
299 	    && archive_entry_pathname_w(entry) == NULL
300 #endif
301 	    ) {
302 		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
303 		    "Can't record entry in tar file without pathname");
304 		return ARCHIVE_FAILED;
305 	}
306 
307 	/* Only regular files (not hardlinks) have data. */
308 	if (archive_entry_hardlink(entry) != NULL ||
309 	    archive_entry_symlink(entry) != NULL ||
310 	    archive_entry_filetype(entry) != AE_IFREG)
311 		archive_entry_set_size(entry, 0);
312 
313 	if (AE_IFDIR == archive_entry_filetype(entry)) {
314 		const char *p;
315 		size_t path_length;
316 		/*
317 		 * Ensure a trailing '/'.  Modify the entry so
318 		 * the client sees the change.
319 		 */
320 #if defined(_WIN32) && !defined(__CYGWIN__)
321 		const wchar_t *wp;
322 
323 		wp = archive_entry_pathname_w(entry);
324 		if (wp != NULL && wp[wcslen(wp) -1] != L'/') {
325 			struct archive_wstring ws;
326 
327 			archive_string_init(&ws);
328 			path_length = wcslen(wp);
329 			if (archive_wstring_ensure(&ws,
330 			    path_length + 2) == NULL) {
331 				archive_set_error(&a->archive, ENOMEM,
332 				    "Can't allocate ustar data");
333 				archive_wstring_free(&ws);
334 				return(ARCHIVE_FATAL);
335 			}
336 			/* Should we keep '\' ? */
337 			if (wp[path_length -1] == L'\\')
338 				path_length--;
339 			archive_wstrncpy(&ws, wp, path_length);
340 			archive_wstrappend_wchar(&ws, L'/');
341 			archive_entry_copy_pathname_w(entry, ws.s);
342 			archive_wstring_free(&ws);
343 			p = NULL;
344 		} else
345 #endif
346 			p = archive_entry_pathname(entry);
347 		/*
348 		 * On Windows, this is a backup operation just in
349 		 * case getting WCS failed. On POSIX, this is a
350 		 * normal operation.
351 		 */
352 		if (p != NULL && p[0] != '\0' && p[strlen(p) - 1] != '/') {
353 			struct archive_string as;
354 
355 			archive_string_init(&as);
356 			path_length = strlen(p);
357 			if (archive_string_ensure(&as,
358 			    path_length + 2) == NULL) {
359 				archive_set_error(&a->archive, ENOMEM,
360 				    "Can't allocate ustar data");
361 				archive_string_free(&as);
362 				return(ARCHIVE_FATAL);
363 			}
364 #if defined(_WIN32) && !defined(__CYGWIN__)
365 			/* NOTE: This might break the pathname
366 			 * if the current code page is CP932 and
367 			 * the pathname includes a character '\'
368 			 * as a part of its multibyte pathname. */
369 			if (p[strlen(p) -1] == '\\')
370 				path_length--;
371 			else
372 #endif
373 			archive_strncpy(&as, p, path_length);
374 			archive_strappend_char(&as, '/');
375 			archive_entry_copy_pathname(entry, as.s);
376 			archive_string_free(&as);
377 		}
378 	}
379 
380 #if defined(_WIN32) && !defined(__CYGWIN__)
381 	/* Make sure the path separators in pathname, hardlink and symlink
382 	 * are all slash '/', not the Windows path separator '\'. */
383 	entry_main = __la_win_entry_in_posix_pathseparator(entry);
384 	if (entry_main == NULL) {
385 		archive_set_error(&a->archive, ENOMEM,
386 		    "Can't allocate ustar data");
387 		return(ARCHIVE_FATAL);
388 	}
389 	if (entry != entry_main)
390 		entry = entry_main;
391 	else
392 		entry_main = NULL;
393 #else
394 	entry_main = NULL;
395 #endif
396 	r = archive_entry_pathname_l(entry, &(gnutar->pathname),
397 	    &(gnutar->pathname_length), sconv);
398 	if (r != 0) {
399 		const char* p_mbs;
400 		if (errno == ENOMEM) {
401 			archive_set_error(&a->archive, ENOMEM,
402 			    "Can't allocate memory for pathname");
403 			ret = ARCHIVE_FATAL;
404 			goto exit_write_header;
405 		}
406 		p_mbs = archive_entry_pathname(entry);
407 		if (p_mbs) {
408 			/* We have a wrongly-encoded MBS pathname.
409 			 * Warn and use it.  */
410 			archive_set_error(&a->archive,
411 			    ARCHIVE_ERRNO_FILE_FORMAT,
412 			    "Can't translate pathname '%s' to %s", p_mbs,
413 			    archive_string_conversion_charset_name(sconv));
414 			ret2 = ARCHIVE_WARN;
415 		} else {
416 			/* We have no MBS pathname.  Fail.  */
417 			archive_set_error(&a->archive,
418 			    ARCHIVE_ERRNO_FILE_FORMAT,
419 			    "Can't translate pathname to %s",
420 			    archive_string_conversion_charset_name(sconv));
421 			return ARCHIVE_FAILED;
422 		}
423 	}
424 	r = archive_entry_uname_l(entry, &(gnutar->uname),
425 	    &(gnutar->uname_length), sconv);
426 	if (r != 0) {
427 		if (errno == ENOMEM) {
428 			archive_set_error(&a->archive, ENOMEM,
429 			    "Can't allocate memory for Uname");
430 			ret = ARCHIVE_FATAL;
431 			goto exit_write_header;
432 		}
433 		archive_set_error(&a->archive,
434 		    ARCHIVE_ERRNO_FILE_FORMAT,
435 		    "Can't translate uname '%s' to %s",
436 		    archive_entry_uname(entry),
437 		    archive_string_conversion_charset_name(sconv));
438 		ret2 = ARCHIVE_WARN;
439 	}
440 	r = archive_entry_gname_l(entry, &(gnutar->gname),
441 	    &(gnutar->gname_length), sconv);
442 	if (r != 0) {
443 		if (errno == ENOMEM) {
444 			archive_set_error(&a->archive, ENOMEM,
445 			    "Can't allocate memory for Gname");
446 			ret = ARCHIVE_FATAL;
447 			goto exit_write_header;
448 		}
449 		archive_set_error(&a->archive,
450 		    ARCHIVE_ERRNO_FILE_FORMAT,
451 		    "Can't translate gname '%s' to %s",
452 		    archive_entry_gname(entry),
453 		    archive_string_conversion_charset_name(sconv));
454 		ret2 = ARCHIVE_WARN;
455 	}
456 
457 	/* If linkname is longer than 100 chars we need to add a 'K' header. */
458 	r = archive_entry_hardlink_l(entry, &(gnutar->linkname),
459 	    &(gnutar->linkname_length), sconv);
460 	if (r != 0) {
461 		if (errno == ENOMEM) {
462 			archive_set_error(&a->archive, ENOMEM,
463 			    "Can't allocate memory for Linkname");
464 			ret = ARCHIVE_FATAL;
465 			goto exit_write_header;
466 		}
467 		archive_set_error(&a->archive,
468 		    ARCHIVE_ERRNO_FILE_FORMAT,
469 		    "Can't translate linkname '%s' to %s",
470 		    archive_entry_hardlink(entry),
471 		    archive_string_conversion_charset_name(sconv));
472 		ret2 = ARCHIVE_WARN;
473 	}
474 	if (gnutar->linkname_length == 0) {
475 		r = archive_entry_symlink_l(entry, &(gnutar->linkname),
476 		    &(gnutar->linkname_length), sconv);
477 		if (r != 0) {
478 			if (errno == ENOMEM) {
479 				archive_set_error(&a->archive, ENOMEM,
480 				    "Can't allocate memory for Linkname");
481 				ret = ARCHIVE_FATAL;
482 				goto exit_write_header;
483 			}
484 			archive_set_error(&a->archive,
485 			    ARCHIVE_ERRNO_FILE_FORMAT,
486 			    "Can't translate linkname '%s' to %s",
487 			    archive_entry_hardlink(entry),
488 			    archive_string_conversion_charset_name(sconv));
489 			ret2 = ARCHIVE_WARN;
490 		}
491 	}
492 	if (gnutar->linkname_length > GNUTAR_linkname_size) {
493 		size_t length = gnutar->linkname_length + 1;
494 		struct archive_entry *temp = archive_entry_new2(&a->archive);
495 
496 		/* Uname/gname here don't really matter since no one reads them;
497 		 * these are the values that GNU tar happens to use on FreeBSD. */
498 		archive_entry_set_uname(temp, "root");
499 		archive_entry_set_gname(temp, "wheel");
500 
501 		archive_entry_set_pathname(temp, "././@LongLink");
502 		archive_entry_set_size(temp, length);
503 		ret = archive_format_gnutar_header(a, buff, temp, 'K');
504 		archive_entry_free(temp);
505 		if (ret < ARCHIVE_WARN)
506 			goto exit_write_header;
507 		ret = __archive_write_output(a, buff, 512);
508 		if (ret < ARCHIVE_WARN)
509 			goto exit_write_header;
510 		/* Write name and trailing null byte. */
511 		ret = __archive_write_output(a, gnutar->linkname, length);
512 		if (ret < ARCHIVE_WARN)
513 			goto exit_write_header;
514 		/* Pad to 512 bytes */
515 		ret = __archive_write_nulls(a, 0x1ff & (-(ssize_t)length));
516 		if (ret < ARCHIVE_WARN)
517 			goto exit_write_header;
518 	}
519 
520 	/* If pathname is longer than 100 chars we need to add an 'L' header. */
521 	if (gnutar->pathname_length > GNUTAR_name_size) {
522 		const char *pathname = gnutar->pathname;
523 		size_t length = gnutar->pathname_length + 1;
524 		struct archive_entry *temp = archive_entry_new2(&a->archive);
525 
526 		/* Uname/gname here don't really matter since no one reads them;
527 		 * these are the values that GNU tar happens to use on FreeBSD. */
528 		archive_entry_set_uname(temp, "root");
529 		archive_entry_set_gname(temp, "wheel");
530 
531 		archive_entry_set_pathname(temp, "././@LongName");
532 		archive_entry_set_size(temp, length);
533 		ret = archive_format_gnutar_header(a, buff, temp, 'L');
534 		archive_entry_free(temp);
535 		if (ret < ARCHIVE_WARN)
536 			goto exit_write_header;
537 		ret = __archive_write_output(a, buff, 512);
538 		if(ret < ARCHIVE_WARN)
539 			goto exit_write_header;
540 		/* Write pathname + trailing null byte. */
541 		ret = __archive_write_output(a, pathname, length);
542 		if(ret < ARCHIVE_WARN)
543 			goto exit_write_header;
544 		/* Pad to multiple of 512 bytes. */
545 		ret = __archive_write_nulls(a, 0x1ff & (-(ssize_t)length));
546 		if (ret < ARCHIVE_WARN)
547 			goto exit_write_header;
548 	}
549 
550 	if (archive_entry_hardlink_is_set(entry)) {
551 		tartype = '1';
552 	} else
553 		switch (archive_entry_filetype(entry)) {
554 		case AE_IFREG: tartype = '0' ; break;
555 		case AE_IFLNK: tartype = '2' ; break;
556 		case AE_IFCHR: tartype = '3' ; break;
557 		case AE_IFBLK: tartype = '4' ; break;
558 		case AE_IFDIR: tartype = '5' ; break;
559 		case AE_IFIFO: tartype = '6' ; break;
560 		default: /* AE_IFSOCK and unknown */
561 			__archive_write_entry_filetype_unsupported(
562                             &a->archive, entry, "gnutar");
563 			ret = ARCHIVE_FAILED;
564 			goto exit_write_header;
565 		}
566 
567 	ret = archive_format_gnutar_header(a, buff, entry, tartype);
568 	if (ret < ARCHIVE_WARN)
569 		goto exit_write_header;
570 	if (ret2 < ret)
571 		ret = ret2;
572 	ret2 = __archive_write_output(a, buff, 512);
573 	if (ret2 < ARCHIVE_WARN) {
574 		ret = ret2;
575 		goto exit_write_header;
576 	}
577 	if (ret2 < ret)
578 		ret = ret2;
579 
580 	gnutar->entry_bytes_remaining = archive_entry_size(entry);
581 	gnutar->entry_padding = 0x1ff & (-(int64_t)gnutar->entry_bytes_remaining);
582 exit_write_header:
583 	archive_entry_free(entry_main);
584 	return (ret);
585 }
586 
587 static int
archive_format_gnutar_header(struct archive_write * a,char h[512],struct archive_entry * entry,char tartype)588 archive_format_gnutar_header(struct archive_write *a, char h[512],
589     struct archive_entry *entry, char tartype)
590 {
591 	unsigned int checksum;
592 	int i, ret;
593 	size_t copy_length;
594 	const char *p;
595 	struct gnutar *gnutar;
596 
597 	gnutar = (struct gnutar *)a->format_data;
598 
599 	ret = 0;
600 
601 	/*
602 	 * The "template header" already includes the signature,
603 	 * various end-of-field markers, and other required elements.
604 	 */
605 	memcpy(h, &template_header, 512);
606 
607 	/*
608 	 * Because the block is already null-filled, and strings
609 	 * are allowed to exactly fill their destination (without null),
610 	 * I use memcpy(dest, src, strlen()) here a lot to copy strings.
611 	 */
612 
613 	if (tartype == 'K' || tartype == 'L') {
614 		p = archive_entry_pathname(entry);
615 		copy_length = strlen(p);
616 	} else {
617 		p = gnutar->pathname;
618 		copy_length = gnutar->pathname_length;
619 	}
620 	if (copy_length > GNUTAR_name_size)
621 		copy_length = GNUTAR_name_size;
622 	memcpy(h + GNUTAR_name_offset, p, copy_length);
623 
624 	if ((copy_length = gnutar->linkname_length) > 0) {
625 		if (copy_length > GNUTAR_linkname_size)
626 			copy_length = GNUTAR_linkname_size;
627 		memcpy(h + GNUTAR_linkname_offset, gnutar->linkname,
628 		    copy_length);
629 	}
630 
631 	/* TODO: How does GNU tar handle unames longer than GNUTAR_uname_size? */
632 	if (tartype == 'K' || tartype == 'L') {
633 		p = archive_entry_uname(entry);
634 		copy_length = strlen(p);
635 	} else {
636 		p = gnutar->uname;
637 		copy_length = gnutar->uname_length;
638 	}
639 	if (copy_length > 0) {
640 		if (copy_length > GNUTAR_uname_size)
641 			copy_length = GNUTAR_uname_size;
642 		memcpy(h + GNUTAR_uname_offset, p, copy_length);
643 	}
644 
645 	/* TODO: How does GNU tar handle gnames longer than GNUTAR_gname_size? */
646 	if (tartype == 'K' || tartype == 'L') {
647 		p = archive_entry_gname(entry);
648 		copy_length = strlen(p);
649 	} else {
650 		p = gnutar->gname;
651 		copy_length = gnutar->gname_length;
652 	}
653 	if (copy_length > 0) {
654 		if (strlen(p) > GNUTAR_gname_size)
655 			copy_length = GNUTAR_gname_size;
656 		memcpy(h + GNUTAR_gname_offset, p, copy_length);
657 	}
658 
659 	/* By truncating the mode here, we ensure it always fits. */
660 	format_octal(archive_entry_mode(entry) & 07777,
661 	    h + GNUTAR_mode_offset, GNUTAR_mode_size);
662 
663 	/* GNU tar supports base-256 here, so should never overflow. */
664 	if (format_number(archive_entry_uid(entry), h + GNUTAR_uid_offset,
665 		GNUTAR_uid_size, GNUTAR_uid_max_size)) {
666 		archive_set_error(&a->archive, ERANGE,
667 		    "Numeric user ID %jd too large for gnutar format",
668 		    (intmax_t)archive_entry_uid(entry));
669 		ret = ARCHIVE_FAILED;
670 	}
671 
672 	/* GNU tar supports base-256 here, so should never overflow. */
673 	if (format_number(archive_entry_gid(entry), h + GNUTAR_gid_offset,
674 		GNUTAR_gid_size, GNUTAR_gid_max_size)) {
675 		archive_set_error(&a->archive, ERANGE,
676 		    "Numeric group ID %jd too large for gnutar format",
677 		    (intmax_t)archive_entry_gid(entry));
678 		ret = ARCHIVE_FAILED;
679 	}
680 
681 	/* GNU tar supports base-256 here, so should never overflow. */
682 	if (format_number(archive_entry_size(entry), h + GNUTAR_size_offset,
683 		GNUTAR_size_size, GNUTAR_size_max_size)) {
684 		archive_set_error(&a->archive, ERANGE,
685 		    "File size out of range");
686 		ret = ARCHIVE_FAILED;
687 	}
688 
689 	/* Shouldn't overflow before 2106, since mtime field is 33 bits. */
690 	format_octal(archive_entry_mtime(entry),
691 	    h + GNUTAR_mtime_offset, GNUTAR_mtime_size);
692 
693 	if (archive_entry_filetype(entry) == AE_IFBLK
694 	    || archive_entry_filetype(entry) == AE_IFCHR) {
695 		if (format_octal(archive_entry_rdevmajor(entry),
696 		    h + GNUTAR_rdevmajor_offset,
697 			GNUTAR_rdevmajor_size)) {
698 			archive_set_error(&a->archive, ERANGE,
699 			    "Major device number too large for gnutar format");
700 			ret = ARCHIVE_FAILED;
701 		}
702 
703 		if (format_octal(archive_entry_rdevminor(entry),
704 		    h + GNUTAR_rdevminor_offset,
705 			GNUTAR_rdevminor_size)) {
706 			archive_set_error(&a->archive, ERANGE,
707 			    "Minor device number too large for gnutar format");
708 			ret = ARCHIVE_FAILED;
709 		}
710 	}
711 
712 	h[GNUTAR_typeflag_offset] = tartype;
713 
714 	checksum = 0;
715 	for (i = 0; i < 512; i++)
716 		checksum += 255 & (unsigned int)h[i];
717 	h[GNUTAR_checksum_offset + 6] = '\0'; /* Can't be pre-set in the template. */
718 	/* h[GNUTAR_checksum_offset + 7] = ' '; */ /* This is pre-set in the template. */
719 	format_octal(checksum, h + GNUTAR_checksum_offset, 6);
720 	return (ret);
721 }
722 
723 /*
724  * Format a number into a field, falling back to base-256 if necessary.
725  */
726 static int
format_number(int64_t v,char * p,int s,int maxsize)727 format_number(int64_t v, char *p, int s, int maxsize)
728 {
729 	int64_t limit = ((int64_t)1 << (s*3));
730 
731 	if (v < limit)
732 		return (format_octal(v, p, s));
733 	return (format_256(v, p, maxsize));
734 }
735 
736 /*
737  * Format a number into the specified field using base-256.
738  */
739 static int
format_256(int64_t v,char * p,int s)740 format_256(int64_t v, char *p, int s)
741 {
742 	p += s;
743 	while (s-- > 0) {
744 		*--p = (char)(v & 0xff);
745 		v >>= 8;
746 	}
747 	*p |= 0x80; /* Set the base-256 marker bit. */
748 	return (0);
749 }
750 
751 /*
752  * Format a number into the specified field using octal.
753  */
754 static int
format_octal(int64_t v,char * p,int s)755 format_octal(int64_t v, char *p, int s)
756 {
757 	int len = s;
758 
759 	/* Octal values can't be negative, so use 0. */
760 	if (v < 0)
761 		v = 0;
762 
763 	p += s;		/* Start at the end and work backwards. */
764 	while (s-- > 0) {
765 		*--p = (char)('0' + (v & 7));
766 		v >>= 3;
767 	}
768 
769 	if (v == 0)
770 		return (0);
771 
772 	/* If it overflowed, fill field with max value. */
773 	while (len-- > 0)
774 		*p++ = '7';
775 
776 	return (-1);
777 }
778