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cpio.c revision 1.13
      1 /*	$NetBSD: cpio.c,v 1.13 2002/02/11 10:57:57 wiz Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1992 Keith Muller.
      5  * Copyright (c) 1992, 1993
      6  *	The Regents of the University of California.  All rights reserved.
      7  *
      8  * This code is derived from software contributed to Berkeley by
      9  * Keith Muller of the University of California, San Diego.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by the University of
     22  *	California, Berkeley and its contributors.
     23  * 4. Neither the name of the University nor the names of its contributors
     24  *    may be used to endorse or promote products derived from this software
     25  *    without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     37  * SUCH DAMAGE.
     38  */
     39 
     40 #include <sys/cdefs.h>
     41 #if defined(__RCSID) && !defined(lint)
     42 #if 0
     43 static char sccsid[] = "@(#)cpio.c	8.1 (Berkeley) 5/31/93";
     44 #else
     45 __RCSID("$NetBSD: cpio.c,v 1.13 2002/02/11 10:57:57 wiz Exp $");
     46 #endif
     47 #endif /* not lint */
     48 
     49 #include <sys/types.h>
     50 #include <sys/time.h>
     51 #include <sys/stat.h>
     52 #include <sys/param.h>
     53 #include <string.h>
     54 #include <ctype.h>
     55 #include <stdio.h>
     56 #include <unistd.h>
     57 #include <stdlib.h>
     58 #include "pax.h"
     59 #include "cpio.h"
     60 #include "extern.h"
     61 
     62 static int rd_nm(ARCHD *, int);
     63 static int rd_ln_nm(ARCHD *);
     64 static int com_rd(ARCHD *);
     65 
     66 /*
     67  * Routines which support the different cpio versions
     68  */
     69 
     70 int cpio_swp_head;		/* binary cpio header byte swap */
     71 
     72 /*
     73  * Routines common to all versions of cpio
     74  */
     75 
     76 /*
     77  * cpio_strd()
     78  *	Fire up the hard link detection code
     79  * Return:
     80  *	0 if ok -1 otherwise (the return values of lnk_start())
     81  */
     82 
     83 int
     84 cpio_strd(void)
     85 {
     86 	return(lnk_start());
     87 }
     88 
     89 /*
     90  * cpio_subtrail()
     91  *	Called to determine if a header block is a valid trailer. We are
     92  *	passed the block, the in_sync flag (which tells us we are in resync
     93  *	mode; looking for a valid header), and cnt (which starts at zero)
     94  *	which is used to count the number of empty blocks we have seen so far.
     95  * Return:
     96  *	0 if a valid trailer, -1 if not a valid trailer,
     97  */
     98 
     99 int
    100 cpio_subtrail(ARCHD *arcn)
    101 {
    102 	/*
    103 	 * look for trailer id in file we are about to process
    104 	 */
    105 	if ((strcmp(arcn->name, TRAILER) == 0) && (arcn->sb.st_size == 0))
    106 		return(0);
    107 	return(-1);
    108 }
    109 
    110 /*
    111  * com_rd()
    112  *	operations common to all cpio read functions.
    113  * Return:
    114  *	0
    115  */
    116 
    117 static int
    118 com_rd(ARCHD *arcn)
    119 {
    120 	arcn->skip = 0;
    121 	arcn->pat = NULL;
    122 	arcn->org_name = arcn->name;
    123 	switch(arcn->sb.st_mode & C_IFMT) {
    124 	case C_ISFIFO:
    125 		arcn->type = PAX_FIF;
    126 		break;
    127 	case C_ISDIR:
    128 		arcn->type = PAX_DIR;
    129 		break;
    130 	case C_ISBLK:
    131 		arcn->type = PAX_BLK;
    132 		break;
    133 	case C_ISCHR:
    134 		arcn->type = PAX_CHR;
    135 		break;
    136 	case C_ISLNK:
    137 		arcn->type = PAX_SLK;
    138 		break;
    139 	case C_ISOCK:
    140 		arcn->type = PAX_SCK;
    141 		break;
    142 	case C_ISCTG:
    143 	case C_ISREG:
    144 	default:
    145 		/*
    146 		 * we have file data, set up skip (pad is set in the format
    147 		 * specific sections)
    148 		 */
    149 		arcn->sb.st_mode = (arcn->sb.st_mode & 0xfff) | C_ISREG;
    150 		arcn->type = PAX_REG;
    151 		arcn->skip = arcn->sb.st_size;
    152 		break;
    153 	}
    154 	if (chk_lnk(arcn) < 0)
    155 		return(-1);
    156 	return(0);
    157 }
    158 
    159 /*
    160  * cpio_end_wr()
    161  *	write the special file with the name trailer in the proper format
    162  * Return:
    163  *	result of the write of the trailer from the cpio specific write func
    164  */
    165 
    166 int
    167 cpio_endwr(void)
    168 {
    169 	ARCHD last;
    170 
    171 	/*
    172 	 * create a trailer request and call the proper format write function
    173 	 */
    174 	memset(&last, 0, sizeof(last));
    175 	last.nlen = sizeof(TRAILER) - 1;
    176 	last.type = PAX_REG;
    177 	last.sb.st_nlink = 1;
    178 	(void)strcpy(last.name, TRAILER);
    179 	return((*frmt->wr)(&last));
    180 }
    181 
    182 /*
    183  * rd_nam()
    184  *	read in the file name which follows the cpio header
    185  * Return:
    186  *	0 if ok, -1 otherwise
    187  */
    188 
    189 static int
    190 rd_nm(ARCHD *arcn, int nsz)
    191 {
    192 	/*
    193 	 * do not even try bogus values
    194 	 */
    195 	if ((nsz == 0) || (nsz > sizeof(arcn->name))) {
    196 		tty_warn(1, "Cpio file name length %d is out of range", nsz);
    197 		return(-1);
    198 	}
    199 
    200 	/*
    201 	 * read the name and make sure it is not empty and is \0 terminated
    202 	 */
    203 	if ((rd_wrbuf(arcn->name,nsz) != nsz) || (arcn->name[nsz-1] != '\0') ||
    204 	    (arcn->name[0] == '\0')) {
    205 		tty_warn(1, "Cpio file name in header is corrupted");
    206 		return(-1);
    207 	}
    208 	return(0);
    209 }
    210 
    211 /*
    212  * rd_ln_nm()
    213  *	read in the link name for a file with links. The link name is stored
    214  *	like file data (and is NOT \0 terminated!)
    215  * Return:
    216  *	0 if ok, -1 otherwise
    217  */
    218 
    219 static int
    220 rd_ln_nm(ARCHD *arcn)
    221 {
    222 	/*
    223 	 * check the length specified for bogus values
    224 	 */
    225 	if ((arcn->sb.st_size == 0) ||
    226 	    (arcn->sb.st_size >= sizeof(arcn->ln_name))) {
    227 		tty_warn(1, "Cpio link name length is invalid: " OFFT_F,
    228 		    (OFFT_T) arcn->sb.st_size);
    229 		return(-1);
    230 	}
    231 
    232 	/*
    233 	 * read in the link name and \0 terminate it
    234 	 */
    235 	if (rd_wrbuf(arcn->ln_name, (int)arcn->sb.st_size) !=
    236 	    (int)arcn->sb.st_size) {
    237 		tty_warn(1, "Cpio link name read error");
    238 		return(-1);
    239 	}
    240 	arcn->ln_nlen = arcn->sb.st_size;
    241 	arcn->ln_name[arcn->ln_nlen] = '\0';
    242 
    243 	/*
    244 	 * watch out for those empty link names
    245 	 */
    246 	if (arcn->ln_name[0] == '\0') {
    247 		tty_warn(1, "Cpio link name is corrupt");
    248 		return(-1);
    249 	}
    250 	return(0);
    251 }
    252 
    253 /*
    254  * Routines common to the extended byte oriented cpio format
    255  */
    256 
    257 /*
    258  * cpio_id()
    259  *	determine if a block given to us is a valid extended byte oriented
    260  *	cpio header
    261  * Return:
    262  *	0 if a valid header, -1 otherwise
    263  */
    264 
    265 int
    266 cpio_id(char *blk, int size)
    267 {
    268 	if ((size < sizeof(HD_CPIO)) ||
    269 	    (strncmp(blk, AMAGIC, sizeof(AMAGIC) - 1) != 0))
    270 		return(-1);
    271 	return(0);
    272 }
    273 
    274 /*
    275  * cpio_rd()
    276  *	determine if a buffer is a byte oriented extended cpio archive entry.
    277  *	convert and store the values in the ARCHD parameter.
    278  * Return:
    279  *	0 if a valid header, -1 otherwise.
    280  */
    281 
    282 int
    283 cpio_rd(ARCHD *arcn, char *buf)
    284 {
    285 	int nsz;
    286 	HD_CPIO *hd;
    287 
    288 	/*
    289 	 * check that this is a valid header, if not return -1
    290 	 */
    291 	if (cpio_id(buf, sizeof(HD_CPIO)) < 0)
    292 		return(-1);
    293 	hd = (HD_CPIO *)buf;
    294 
    295 	/*
    296 	 * byte oriented cpio (posix) does not have padding! extract the octal
    297 	 * ascii fields from the header
    298 	 */
    299 	arcn->pad = 0L;
    300 	arcn->sb.st_dev = (dev_t)asc_ul(hd->c_dev, sizeof(hd->c_dev), OCT);
    301 	arcn->sb.st_ino = (ino_t)asc_ul(hd->c_ino, sizeof(hd->c_ino), OCT);
    302 	arcn->sb.st_mode = (mode_t)asc_ul(hd->c_mode, sizeof(hd->c_mode), OCT);
    303 	arcn->sb.st_uid = (uid_t)asc_ul(hd->c_uid, sizeof(hd->c_uid), OCT);
    304 	arcn->sb.st_gid = (gid_t)asc_ul(hd->c_gid, sizeof(hd->c_gid), OCT);
    305 	arcn->sb.st_nlink = (nlink_t)asc_ul(hd->c_nlink, sizeof(hd->c_nlink),
    306 	    OCT);
    307 	arcn->sb.st_rdev = (dev_t)asc_ul(hd->c_rdev, sizeof(hd->c_rdev), OCT);
    308 	arcn->sb.st_mtime = (time_t)asc_ul(hd->c_mtime, sizeof(hd->c_mtime),
    309 	    OCT);
    310 	arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
    311 	arcn->sb.st_size = (off_t)ASC_OFFT(hd->c_filesize,
    312 	    sizeof(hd->c_filesize), OCT);
    313 
    314 	/*
    315 	 * check name size and if valid, read in the name of this entry (name
    316 	 * follows header in the archive)
    317 	 */
    318 	if ((nsz = (int)asc_ul(hd->c_namesize,sizeof(hd->c_namesize),OCT)) < 2)
    319 		return(-1);
    320 	arcn->nlen = nsz - 1;
    321 	if (rd_nm(arcn, nsz) < 0)
    322 		return(-1);
    323 
    324 	if (((arcn->sb.st_mode&C_IFMT) != C_ISLNK)||(arcn->sb.st_size == 0)) {
    325 		/*
    326 		 * no link name to read for this file
    327 		 */
    328 		arcn->ln_nlen = 0;
    329 		arcn->ln_name[0] = '\0';
    330 		return(com_rd(arcn));
    331 	}
    332 
    333 	/*
    334 	 * check link name size and read in the link name. Link names are
    335 	 * stored like file data.
    336 	 */
    337 	if (rd_ln_nm(arcn) < 0)
    338 		return(-1);
    339 
    340 	/*
    341 	 * we have a valid header (with a link)
    342 	 */
    343 	return(com_rd(arcn));
    344 }
    345 
    346 /*
    347  * cpio_endrd()
    348  *	no cleanup needed here, just return size of the trailer (for append)
    349  * Return:
    350  *	size of trailer header in this format
    351  */
    352 
    353 off_t
    354 cpio_endrd(void)
    355 {
    356 	return((off_t)(sizeof(HD_CPIO) + sizeof(TRAILER)));
    357 }
    358 
    359 /*
    360  * cpio_stwr()
    361  *	start up the device mapping table
    362  * Return:
    363  *	0 if ok, -1 otherwise (what dev_start() returns)
    364  */
    365 
    366 int
    367 cpio_stwr(void)
    368 {
    369 	return(dev_start());
    370 }
    371 
    372 /*
    373  * cpio_wr()
    374  *	copy the data in the ARCHD to buffer in extended byte oriented cpio
    375  *	format.
    376  * Return
    377  *	0 if file has data to be written after the header, 1 if file has NO
    378  *	data to write after the header, -1 if archive write failed
    379  */
    380 
    381 int
    382 cpio_wr(ARCHD *arcn)
    383 {
    384 	HD_CPIO *hd;
    385 	int nsz;
    386 	char hdblk[sizeof(HD_CPIO)];
    387 
    388 	/*
    389 	 * check and repair truncated device and inode fields in the header
    390 	 */
    391 	if (map_dev(arcn, (u_long)CPIO_MASK, (u_long)CPIO_MASK) < 0)
    392 		return(-1);
    393 
    394 	arcn->pad = 0L;
    395 	nsz = arcn->nlen + 1;
    396 	hd = (HD_CPIO *)hdblk;
    397 	if ((arcn->type != PAX_BLK) && (arcn->type != PAX_CHR))
    398 		arcn->sb.st_rdev = 0;
    399 
    400 	switch(arcn->type) {
    401 	case PAX_CTG:
    402 	case PAX_REG:
    403 	case PAX_HRG:
    404 		/*
    405 		 * set data size for file data
    406 		 */
    407 		if (OFFT_ASC(arcn->sb.st_size, hd->c_filesize,
    408 		    sizeof(hd->c_filesize), OCT)) {
    409 			tty_warn(1,"File is too large for cpio format %s",
    410 			    arcn->org_name);
    411 			return(1);
    412 		}
    413 		break;
    414 	case PAX_SLK:
    415 		/*
    416 		 * set data size to hold link name
    417 		 */
    418 		if (ul_asc((u_long)arcn->ln_nlen, hd->c_filesize,
    419 		    sizeof(hd->c_filesize), OCT))
    420 			goto out;
    421 		break;
    422 	default:
    423 		/*
    424 		 * all other file types have no file data
    425 		 */
    426 		if (ul_asc((u_long)0, hd->c_filesize, sizeof(hd->c_filesize),
    427 		     OCT))
    428 			goto out;
    429 		break;
    430 	}
    431 
    432 	/*
    433 	 * copy the values to the header using octal ascii
    434 	 */
    435 	if (ul_asc((u_long)MAGIC, hd->c_magic, sizeof(hd->c_magic), OCT) ||
    436 	    ul_asc((u_long)arcn->sb.st_dev, hd->c_dev, sizeof(hd->c_dev),
    437 		OCT) ||
    438 	    ul_asc((u_long)arcn->sb.st_ino, hd->c_ino, sizeof(hd->c_ino),
    439 		OCT) ||
    440 	    ul_asc((u_long)arcn->sb.st_mode, hd->c_mode, sizeof(hd->c_mode),
    441 		OCT) ||
    442 	    ul_asc((u_long)arcn->sb.st_uid, hd->c_uid, sizeof(hd->c_uid),
    443 		OCT) ||
    444 	    ul_asc((u_long)arcn->sb.st_gid, hd->c_gid, sizeof(hd->c_gid),
    445 		OCT) ||
    446 	    ul_asc((u_long)arcn->sb.st_nlink, hd->c_nlink, sizeof(hd->c_nlink),
    447 		 OCT) ||
    448 	    ul_asc((u_long)arcn->sb.st_rdev, hd->c_rdev, sizeof(hd->c_rdev),
    449 		OCT) ||
    450 	    ul_asc((u_long)arcn->sb.st_mtime,hd->c_mtime,sizeof(hd->c_mtime),
    451 		OCT) ||
    452 	    ul_asc((u_long)nsz, hd->c_namesize, sizeof(hd->c_namesize), OCT))
    453 		goto out;
    454 
    455 	/*
    456 	 * write the file name to the archive
    457 	 */
    458 	if ((wr_rdbuf(hdblk, (int)sizeof(HD_CPIO)) < 0) ||
    459 	    (wr_rdbuf(arcn->name, nsz) < 0)) {
    460 		tty_warn(1, "Unable to write cpio header for %s",
    461 		    arcn->org_name);
    462 		return(-1);
    463 	}
    464 
    465 	/*
    466 	 * if this file has data, we are done. The caller will write the file
    467 	 * data, if we are link tell caller we are done, go to next file
    468 	 */
    469 	if ((arcn->type == PAX_CTG) || (arcn->type == PAX_REG) ||
    470 	    (arcn->type == PAX_HRG))
    471 		return(0);
    472 	if (arcn->type != PAX_SLK)
    473 		return(1);
    474 
    475 	/*
    476 	 * write the link name to the archive, tell the caller to go to the
    477 	 * next file as we are done.
    478 	 */
    479 	if (wr_rdbuf(arcn->ln_name, arcn->ln_nlen) < 0) {
    480 		tty_warn(1,"Unable to write cpio link name for %s",
    481 		    arcn->org_name);
    482 		return(-1);
    483 	}
    484 	return(1);
    485 
    486     out:
    487 	/*
    488 	 * header field is out of range
    489 	 */
    490 	tty_warn(1, "Cpio header field is too small to store file %s",
    491 	    arcn->org_name);
    492 	return(1);
    493 }
    494 
    495 /*
    496  * Routines common to the system VR4 version of cpio (with/without file CRC)
    497  */
    498 
    499 /*
    500  * vcpio_id()
    501  *	determine if a block given to us is a valid system VR4 cpio header
    502  *	WITHOUT crc. WATCH it the magic cookies are in OCTAL, the header
    503  *	uses HEX
    504  * Return:
    505  *	0 if a valid header, -1 otherwise
    506  */
    507 
    508 int
    509 vcpio_id(char *blk, int size)
    510 {
    511 	if ((size < sizeof(HD_VCPIO)) ||
    512 	    (strncmp(blk, AVMAGIC, sizeof(AVMAGIC) - 1) != 0))
    513 		return(-1);
    514 	return(0);
    515 }
    516 
    517 /*
    518  * crc_id()
    519  *	determine if a block given to us is a valid system VR4 cpio header
    520  *	WITH crc. WATCH it the magic cookies are in OCTAL the header uses HEX
    521  * Return:
    522  *	0 if a valid header, -1 otherwise
    523  */
    524 
    525 int
    526 crc_id(char *blk, int size)
    527 {
    528 	if ((size < sizeof(HD_VCPIO)) ||
    529 	    (strncmp(blk, AVCMAGIC, sizeof(AVCMAGIC) - 1) != 0))
    530 		return(-1);
    531 	return(0);
    532 }
    533 
    534 /*
    535  * crc_strd()
    536  *	set file data CRC calculations. Fire up the hard link detection code
    537  * Return:
    538  *	0 if ok -1 otherwise (the return values of lnk_start())
    539  */
    540 
    541 int
    542 crc_strd(void)
    543 {
    544 	docrc = 1;
    545 	return(lnk_start());
    546 }
    547 
    548 /*
    549  * vcpio_rd()
    550  *	determine if a buffer is a system VR4 archive entry. (with/without CRC)
    551  *	convert and store the values in the ARCHD parameter.
    552  * Return:
    553  *	0 if a valid header, -1 otherwise.
    554  */
    555 
    556 int
    557 vcpio_rd(ARCHD *arcn, char *buf)
    558 {
    559 	HD_VCPIO *hd;
    560 	dev_t devminor;
    561 	dev_t devmajor;
    562 	int nsz;
    563 
    564 	/*
    565 	 * during the id phase it was determined if we were using CRC, use the
    566 	 * proper id routine.
    567 	 */
    568 	if (docrc) {
    569 		if (crc_id(buf, sizeof(HD_VCPIO)) < 0)
    570 			return(-1);
    571 	} else {
    572 		if (vcpio_id(buf, sizeof(HD_VCPIO)) < 0)
    573 			return(-1);
    574 	}
    575 
    576 	hd = (HD_VCPIO *)buf;
    577 	arcn->pad = 0L;
    578 
    579 	/*
    580 	 * extract the hex ascii fields from the header
    581 	 */
    582 	arcn->sb.st_ino = (ino_t)asc_ul(hd->c_ino, sizeof(hd->c_ino), HEX);
    583 	arcn->sb.st_mode = (mode_t)asc_ul(hd->c_mode, sizeof(hd->c_mode), HEX);
    584 	arcn->sb.st_uid = (uid_t)asc_ul(hd->c_uid, sizeof(hd->c_uid), HEX);
    585 	arcn->sb.st_gid = (gid_t)asc_ul(hd->c_gid, sizeof(hd->c_gid), HEX);
    586 	arcn->sb.st_mtime = (time_t)asc_ul(hd->c_mtime,sizeof(hd->c_mtime),HEX);
    587 	arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
    588 	arcn->sb.st_size = (off_t)ASC_OFFT(hd->c_filesize,
    589 	    sizeof(hd->c_filesize), HEX);
    590 	arcn->sb.st_nlink = (nlink_t)asc_ul(hd->c_nlink, sizeof(hd->c_nlink),
    591 	    HEX);
    592 	devmajor = (dev_t)asc_ul(hd->c_maj, sizeof(hd->c_maj), HEX);
    593 	devminor = (dev_t)asc_ul(hd->c_min, sizeof(hd->c_min), HEX);
    594 	arcn->sb.st_dev = TODEV(devmajor, devminor);
    595 	devmajor = (dev_t)asc_ul(hd->c_rmaj, sizeof(hd->c_maj), HEX);
    596 	devminor = (dev_t)asc_ul(hd->c_rmin, sizeof(hd->c_min), HEX);
    597 	arcn->sb.st_rdev = TODEV(devmajor, devminor);
    598 	arcn->crc = asc_ul(hd->c_chksum, sizeof(hd->c_chksum), HEX);
    599 
    600 	/*
    601 	 * check the length of the file name, if ok read it in, return -1 if
    602 	 * bogus
    603 	 */
    604 	if ((nsz = (int)asc_ul(hd->c_namesize,sizeof(hd->c_namesize),HEX)) < 2)
    605 		return(-1);
    606 	arcn->nlen = nsz - 1;
    607 	if (rd_nm(arcn, nsz) < 0)
    608 		return(-1);
    609 
    610 	/*
    611 	 * skip padding. header + filename is aligned to 4 byte boundaries
    612 	 */
    613 	if (rd_skip((off_t)(VCPIO_PAD(sizeof(HD_VCPIO) + nsz))) < 0)
    614 		return(-1);
    615 
    616 	/*
    617 	 * if not a link (or a file with no data), calculate pad size (for
    618 	 * padding which follows the file data), clear the link name and return
    619 	 */
    620 	if (((arcn->sb.st_mode&C_IFMT) != C_ISLNK)||(arcn->sb.st_size == 0)) {
    621 		/*
    622 		 * we have a valid header (not a link)
    623 		 */
    624 		arcn->ln_nlen = 0;
    625 		arcn->ln_name[0] = '\0';
    626 		arcn->pad = VCPIO_PAD(arcn->sb.st_size);
    627 		return(com_rd(arcn));
    628 	}
    629 
    630 	/*
    631 	 * read in the link name and skip over the padding
    632 	 */
    633 	if ((rd_ln_nm(arcn) < 0) ||
    634 	    (rd_skip((off_t)(VCPIO_PAD(arcn->sb.st_size))) < 0))
    635 		return(-1);
    636 
    637 	/*
    638 	 * we have a valid header (with a link)
    639 	 */
    640 	return(com_rd(arcn));
    641 }
    642 
    643 /*
    644  * vcpio_endrd()
    645  *	no cleanup needed here, just return size of the trailer (for append)
    646  * Return:
    647  *	size of trailer header in this format
    648  */
    649 
    650 off_t
    651 vcpio_endrd(void)
    652 {
    653 	return((off_t)(sizeof(HD_VCPIO) + sizeof(TRAILER) +
    654 		(VCPIO_PAD(sizeof(HD_VCPIO) + sizeof(TRAILER)))));
    655 }
    656 
    657 /*
    658  * crc_stwr()
    659  *	start up the device mapping table, enable crc file calculation
    660  * Return:
    661  *	0 if ok, -1 otherwise (what dev_start() returns)
    662  */
    663 
    664 int
    665 crc_stwr(void)
    666 {
    667 	docrc = 1;
    668 	return(dev_start());
    669 }
    670 
    671 /*
    672  * vcpio_wr()
    673  *	copy the data in the ARCHD to buffer in system VR4 cpio
    674  *	(with/without crc) format.
    675  * Return
    676  *	0 if file has data to be written after the header, 1 if file has
    677  *	NO data to write after the header, -1 if archive write failed
    678  */
    679 
    680 int
    681 vcpio_wr(ARCHD *arcn)
    682 {
    683 	HD_VCPIO *hd;
    684 	unsigned int nsz;
    685 	char hdblk[sizeof(HD_VCPIO)];
    686 
    687 	/*
    688 	 * check and repair truncated device and inode fields in the cpio
    689 	 * header
    690 	 */
    691 	if (map_dev(arcn, (u_long)VCPIO_MASK, (u_long)VCPIO_MASK) < 0)
    692 		return(-1);
    693 	nsz = arcn->nlen + 1;
    694 	hd = (HD_VCPIO *)hdblk;
    695 	if ((arcn->type != PAX_BLK) && (arcn->type != PAX_CHR))
    696 		arcn->sb.st_rdev = 0;
    697 
    698 	/*
    699 	 * add the proper magic value depending whether we were asked for
    700 	 * file data crc's, and the crc if needed.
    701 	 */
    702 	if (docrc) {
    703 		if (ul_asc((u_long)VCMAGIC, hd->c_magic, sizeof(hd->c_magic),
    704 			OCT) ||
    705 		    ul_asc((u_long)arcn->crc,hd->c_chksum,sizeof(hd->c_chksum),
    706 			HEX))
    707 			goto out;
    708 	} else {
    709 		if (ul_asc((u_long)VMAGIC, hd->c_magic, sizeof(hd->c_magic),
    710 			OCT) ||
    711 		    ul_asc((u_long)0L, hd->c_chksum, sizeof(hd->c_chksum),HEX))
    712 			goto out;
    713 	}
    714 
    715 	switch(arcn->type) {
    716 	case PAX_CTG:
    717 	case PAX_REG:
    718 	case PAX_HRG:
    719 		/*
    720 		 * caller will copy file data to the archive. tell him how
    721 		 * much to pad.
    722 		 */
    723 		arcn->pad = VCPIO_PAD(arcn->sb.st_size);
    724 		if (OFFT_ASC(arcn->sb.st_size, hd->c_filesize,
    725 		    sizeof(hd->c_filesize), HEX)) {
    726 			tty_warn(1,"File is too large for sv4cpio format %s",
    727 			    arcn->org_name);
    728 			return(1);
    729 		}
    730 		break;
    731 	case PAX_SLK:
    732 		/*
    733 		 * no file data for the caller to process, the file data has
    734 		 * the size of the link
    735 		 */
    736 		arcn->pad = 0L;
    737 		if (ul_asc((u_long)arcn->ln_nlen, hd->c_filesize,
    738 		    sizeof(hd->c_filesize), HEX))
    739 			goto out;
    740 		break;
    741 	default:
    742 		/*
    743 		 * no file data for the caller to process
    744 		 */
    745 		arcn->pad = 0L;
    746 		if (ul_asc((u_long)0L, hd->c_filesize, sizeof(hd->c_filesize),
    747 		    HEX))
    748 			goto out;
    749 		break;
    750 	}
    751 
    752 	/*
    753 	 * set the other fields in the header
    754 	 */
    755 	if (ul_asc((u_long)arcn->sb.st_ino, hd->c_ino, sizeof(hd->c_ino),
    756 		HEX) ||
    757 	    ul_asc((u_long)arcn->sb.st_mode, hd->c_mode, sizeof(hd->c_mode),
    758 		HEX) ||
    759 	    ul_asc((u_long)arcn->sb.st_uid, hd->c_uid, sizeof(hd->c_uid),
    760 		HEX) ||
    761 	    ul_asc((u_long)arcn->sb.st_gid, hd->c_gid, sizeof(hd->c_gid),
    762 		HEX) ||
    763 	    ul_asc((u_long)arcn->sb.st_mtime, hd->c_mtime, sizeof(hd->c_mtime),
    764 		HEX) ||
    765 	    ul_asc((u_long)arcn->sb.st_nlink, hd->c_nlink, sizeof(hd->c_nlink),
    766 		HEX) ||
    767 	    ul_asc((u_long)MAJOR(arcn->sb.st_dev),hd->c_maj, sizeof(hd->c_maj),
    768 		HEX) ||
    769 	    ul_asc((u_long)MINOR(arcn->sb.st_dev),hd->c_min, sizeof(hd->c_min),
    770 		HEX) ||
    771 	    ul_asc((u_long)MAJOR(arcn->sb.st_rdev),hd->c_rmaj,sizeof(hd->c_maj),
    772 		HEX) ||
    773 	    ul_asc((u_long)MINOR(arcn->sb.st_rdev),hd->c_rmin,sizeof(hd->c_min),
    774 		HEX) ||
    775 	    ul_asc((u_long)nsz, hd->c_namesize, sizeof(hd->c_namesize), HEX))
    776 		goto out;
    777 
    778 	/*
    779 	 * write the header, the file name and padding as required.
    780 	 */
    781 	if ((wr_rdbuf(hdblk, (int)sizeof(HD_VCPIO)) < 0) ||
    782 	    (wr_rdbuf(arcn->name, (int)nsz) < 0)  ||
    783 	    (wr_skip((off_t)(VCPIO_PAD(sizeof(HD_VCPIO) + nsz))) < 0)) {
    784 		tty_warn(1,"Could not write sv4cpio header for %s",
    785 		    arcn->org_name);
    786 		return(-1);
    787 	}
    788 
    789 	/*
    790 	 * if we have file data, tell the caller we are done, copy the file
    791 	 */
    792 	if ((arcn->type == PAX_CTG) || (arcn->type == PAX_REG) ||
    793 	    (arcn->type == PAX_HRG))
    794 		return(0);
    795 
    796 	/*
    797 	 * if we are not a link, tell the caller we are done, go to next file
    798 	 */
    799 	if (arcn->type != PAX_SLK)
    800 		return(1);
    801 
    802 	/*
    803 	 * write the link name, tell the caller we are done.
    804 	 */
    805 	if ((wr_rdbuf(arcn->ln_name, arcn->ln_nlen) < 0) ||
    806 	    (wr_skip((off_t)(VCPIO_PAD(arcn->ln_nlen))) < 0)) {
    807 		tty_warn(1,"Could not write sv4cpio link name for %s",
    808 		    arcn->org_name);
    809 		return(-1);
    810 	}
    811 	return(1);
    812 
    813     out:
    814 	/*
    815 	 * header field is out of range
    816 	 */
    817 	tty_warn(1,"Sv4cpio header field is too small for file %s",
    818 	    arcn->org_name);
    819 	return(1);
    820 }
    821 
    822 /*
    823  * Routines common to the old binary header cpio
    824  */
    825 
    826 /*
    827  * bcpio_id()
    828  *	determine if a block given to us is a old binary cpio header
    829  *	(with/without header byte swapping)
    830  * Return:
    831  *	0 if a valid header, -1 otherwise
    832  */
    833 
    834 int
    835 bcpio_id(char *blk, int size)
    836 {
    837 	if (size < sizeof(HD_BCPIO))
    838 		return(-1);
    839 
    840 	/*
    841 	 * check both normal and byte swapped magic cookies
    842 	 */
    843 	if (((u_short)SHRT_EXT(blk)) == MAGIC)
    844 		return(0);
    845 	if (((u_short)RSHRT_EXT(blk)) == MAGIC) {
    846 		if (!cpio_swp_head)
    847 			++cpio_swp_head;
    848 		return(0);
    849 	}
    850 	return(-1);
    851 }
    852 
    853 /*
    854  * bcpio_rd()
    855  *	determine if a buffer is a old binary archive entry. (it may have byte
    856  *	swapped header) convert and store the values in the ARCHD parameter.
    857  *	This is a very old header format and should not really be used.
    858  * Return:
    859  *	0 if a valid header, -1 otherwise.
    860  */
    861 
    862 int
    863 bcpio_rd(ARCHD *arcn, char *buf)
    864 {
    865 	HD_BCPIO *hd;
    866 	int nsz;
    867 
    868 	/*
    869 	 * check the header
    870 	 */
    871 	if (bcpio_id(buf, sizeof(HD_BCPIO)) < 0)
    872 		return(-1);
    873 
    874 	arcn->pad = 0L;
    875 	hd = (HD_BCPIO *)buf;
    876 	if (cpio_swp_head) {
    877 		/*
    878 		 * header has swapped bytes on 16 bit boundaries
    879 		 */
    880 		arcn->sb.st_dev = (dev_t)(RSHRT_EXT(hd->h_dev));
    881 		arcn->sb.st_ino = (ino_t)(RSHRT_EXT(hd->h_ino));
    882 		arcn->sb.st_mode = (mode_t)(RSHRT_EXT(hd->h_mode));
    883 		arcn->sb.st_uid = (uid_t)(RSHRT_EXT(hd->h_uid));
    884 		arcn->sb.st_gid = (gid_t)(RSHRT_EXT(hd->h_gid));
    885 		arcn->sb.st_nlink = (nlink_t)(RSHRT_EXT(hd->h_nlink));
    886 		arcn->sb.st_rdev = (dev_t)(RSHRT_EXT(hd->h_rdev));
    887 		arcn->sb.st_mtime = (time_t)(RSHRT_EXT(hd->h_mtime_1));
    888 		arcn->sb.st_mtime =  (arcn->sb.st_mtime << 16) |
    889 			((time_t)(RSHRT_EXT(hd->h_mtime_2)));
    890 		arcn->sb.st_size = (off_t)(RSHRT_EXT(hd->h_filesize_1));
    891 		arcn->sb.st_size = (arcn->sb.st_size << 16) |
    892 			((off_t)(RSHRT_EXT(hd->h_filesize_2)));
    893 		nsz = (int)(RSHRT_EXT(hd->h_namesize));
    894 	} else {
    895 		arcn->sb.st_dev = (dev_t)(SHRT_EXT(hd->h_dev));
    896 		arcn->sb.st_ino = (ino_t)(SHRT_EXT(hd->h_ino));
    897 		arcn->sb.st_mode = (mode_t)(SHRT_EXT(hd->h_mode));
    898 		arcn->sb.st_uid = (uid_t)(SHRT_EXT(hd->h_uid));
    899 		arcn->sb.st_gid = (gid_t)(SHRT_EXT(hd->h_gid));
    900 		arcn->sb.st_nlink = (nlink_t)(SHRT_EXT(hd->h_nlink));
    901 		arcn->sb.st_rdev = (dev_t)(SHRT_EXT(hd->h_rdev));
    902 		arcn->sb.st_mtime = (time_t)(SHRT_EXT(hd->h_mtime_1));
    903 		arcn->sb.st_mtime =  (arcn->sb.st_mtime << 16) |
    904 			((time_t)(SHRT_EXT(hd->h_mtime_2)));
    905 		arcn->sb.st_size = (off_t)(SHRT_EXT(hd->h_filesize_1));
    906 		arcn->sb.st_size = (arcn->sb.st_size << 16) |
    907 			((off_t)(SHRT_EXT(hd->h_filesize_2)));
    908 		nsz = (int)(SHRT_EXT(hd->h_namesize));
    909 	}
    910 	arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
    911 
    912 	/*
    913 	 * check the file name size, if bogus give up. otherwise read the file
    914 	 * name
    915 	 */
    916 	if (nsz < 2)
    917 		return(-1);
    918 	arcn->nlen = nsz - 1;
    919 	if (rd_nm(arcn, nsz) < 0)
    920 		return(-1);
    921 
    922 	/*
    923 	 * header + file name are aligned to 2 byte boundaries, skip if needed
    924 	 */
    925 	if (rd_skip((off_t)(BCPIO_PAD(sizeof(HD_BCPIO) + nsz))) < 0)
    926 		return(-1);
    927 
    928 	/*
    929 	 * if not a link (or a file with no data), calculate pad size (for
    930 	 * padding which follows the file data), clear the link name and return
    931 	 */
    932 	if (((arcn->sb.st_mode & C_IFMT) != C_ISLNK)||(arcn->sb.st_size == 0)){
    933 		/*
    934 		 * we have a valid header (not a link)
    935 		 */
    936 		arcn->ln_nlen = 0;
    937 		arcn->ln_name[0] = '\0';
    938 		arcn->pad = BCPIO_PAD(arcn->sb.st_size);
    939 		return(com_rd(arcn));
    940 	}
    941 
    942 	if ((rd_ln_nm(arcn) < 0) ||
    943 	    (rd_skip((off_t)(BCPIO_PAD(arcn->sb.st_size))) < 0))
    944 		return(-1);
    945 
    946 	/*
    947 	 * we have a valid header (with a link)
    948 	 */
    949 	return(com_rd(arcn));
    950 }
    951 
    952 /*
    953  * bcpio_endrd()
    954  *	no cleanup needed here, just return size of the trailer (for append)
    955  * Return:
    956  *	size of trailer header in this format
    957  */
    958 
    959 off_t
    960 bcpio_endrd(void)
    961 {
    962 	return((off_t)(sizeof(HD_BCPIO) + sizeof(TRAILER) +
    963 		(BCPIO_PAD(sizeof(HD_BCPIO) + sizeof(TRAILER)))));
    964 }
    965 
    966 /*
    967  * bcpio_wr()
    968  *	copy the data in the ARCHD to buffer in old binary cpio format
    969  *	There is a real chance of field overflow with this critter. So we
    970  *	always check the conversion is ok. nobody in his their right mind
    971  *	should write an archive in this format...
    972  * Return
    973  *	0 if file has data to be written after the header, 1 if file has NO
    974  *	data to write after the header, -1 if archive write failed
    975  */
    976 
    977 int
    978 bcpio_wr(ARCHD *arcn)
    979 {
    980 	HD_BCPIO *hd;
    981 	int nsz;
    982 	char hdblk[sizeof(HD_BCPIO)];
    983 	off_t t_offt;
    984 	int t_int;
    985 	time_t t_timet;
    986 
    987 	/*
    988 	 * check and repair truncated device and inode fields in the cpio
    989 	 * header
    990 	 */
    991 	if (map_dev(arcn, (u_long)BCPIO_MASK, (u_long)BCPIO_MASK) < 0)
    992 		return(-1);
    993 
    994 	if ((arcn->type != PAX_BLK) && (arcn->type != PAX_CHR))
    995 		arcn->sb.st_rdev = 0;
    996 	hd = (HD_BCPIO *)hdblk;
    997 
    998 	switch(arcn->type) {
    999 	case PAX_CTG:
   1000 	case PAX_REG:
   1001 	case PAX_HRG:
   1002 		/*
   1003 		 * caller will copy file data to the archive. tell him how
   1004 		 * much to pad.
   1005 		 */
   1006 		arcn->pad = BCPIO_PAD(arcn->sb.st_size);
   1007 		hd->h_filesize_1[0] = CHR_WR_0(arcn->sb.st_size);
   1008 		hd->h_filesize_1[1] = CHR_WR_1(arcn->sb.st_size);
   1009 		hd->h_filesize_2[0] = CHR_WR_2(arcn->sb.st_size);
   1010 		hd->h_filesize_2[1] = CHR_WR_3(arcn->sb.st_size);
   1011 		t_offt = (off_t)(SHRT_EXT(hd->h_filesize_1));
   1012 		t_offt = (t_offt<<16) | ((off_t)(SHRT_EXT(hd->h_filesize_2)));
   1013 		if (arcn->sb.st_size != t_offt) {
   1014 			tty_warn(1,"File is too large for bcpio format %s",
   1015 			    arcn->org_name);
   1016 			return(1);
   1017 		}
   1018 		break;
   1019 	case PAX_SLK:
   1020 		/*
   1021 		 * no file data for the caller to process, the file data has
   1022 		 * the size of the link
   1023 		 */
   1024 		arcn->pad = 0L;
   1025 		hd->h_filesize_1[0] = CHR_WR_0(arcn->ln_nlen);
   1026 		hd->h_filesize_1[1] = CHR_WR_1(arcn->ln_nlen);
   1027 		hd->h_filesize_2[0] = CHR_WR_2(arcn->ln_nlen);
   1028 		hd->h_filesize_2[1] = CHR_WR_3(arcn->ln_nlen);
   1029 		t_int = (int)(SHRT_EXT(hd->h_filesize_1));
   1030 		t_int = (t_int << 16) | ((int)(SHRT_EXT(hd->h_filesize_2)));
   1031 		if (arcn->ln_nlen != t_int)
   1032 			goto out;
   1033 		break;
   1034 	default:
   1035 		/*
   1036 		 * no file data for the caller to process
   1037 		 */
   1038 		arcn->pad = 0L;
   1039 		hd->h_filesize_1[0] = (char)0;
   1040 		hd->h_filesize_1[1] = (char)0;
   1041 		hd->h_filesize_2[0] = (char)0;
   1042 		hd->h_filesize_2[1] = (char)0;
   1043 		break;
   1044 	}
   1045 
   1046 	/*
   1047 	 * build up the rest of the fields
   1048 	 */
   1049 	hd->h_magic[0] = CHR_WR_2(MAGIC);
   1050 	hd->h_magic[1] = CHR_WR_3(MAGIC);
   1051 	hd->h_dev[0] = CHR_WR_2(arcn->sb.st_dev);
   1052 	hd->h_dev[1] = CHR_WR_3(arcn->sb.st_dev);
   1053 	if (arcn->sb.st_dev != (dev_t)(SHRT_EXT(hd->h_dev)))
   1054 		goto out;
   1055 	hd->h_ino[0] = CHR_WR_2(arcn->sb.st_ino);
   1056 	hd->h_ino[1] = CHR_WR_3(arcn->sb.st_ino);
   1057 	if (arcn->sb.st_ino != (ino_t)(SHRT_EXT(hd->h_ino)))
   1058 		goto out;
   1059 	hd->h_mode[0] = CHR_WR_2(arcn->sb.st_mode);
   1060 	hd->h_mode[1] = CHR_WR_3(arcn->sb.st_mode);
   1061 	if (arcn->sb.st_mode != (mode_t)(SHRT_EXT(hd->h_mode)))
   1062 		goto out;
   1063 	hd->h_uid[0] = CHR_WR_2(arcn->sb.st_uid);
   1064 	hd->h_uid[1] = CHR_WR_3(arcn->sb.st_uid);
   1065 	if (arcn->sb.st_uid != (uid_t)(SHRT_EXT(hd->h_uid)))
   1066 		goto out;
   1067 	hd->h_gid[0] = CHR_WR_2(arcn->sb.st_gid);
   1068 	hd->h_gid[1] = CHR_WR_3(arcn->sb.st_gid);
   1069 	if (arcn->sb.st_gid != (gid_t)(SHRT_EXT(hd->h_gid)))
   1070 		goto out;
   1071 	hd->h_nlink[0] = CHR_WR_2(arcn->sb.st_nlink);
   1072 	hd->h_nlink[1] = CHR_WR_3(arcn->sb.st_nlink);
   1073 	if (arcn->sb.st_nlink != (nlink_t)(SHRT_EXT(hd->h_nlink)))
   1074 		goto out;
   1075 	hd->h_rdev[0] = CHR_WR_2(arcn->sb.st_rdev);
   1076 	hd->h_rdev[1] = CHR_WR_3(arcn->sb.st_rdev);
   1077 	if (arcn->sb.st_rdev != (dev_t)(SHRT_EXT(hd->h_rdev)))
   1078 		goto out;
   1079 	hd->h_mtime_1[0] = CHR_WR_0(arcn->sb.st_mtime);
   1080 	hd->h_mtime_1[1] = CHR_WR_1(arcn->sb.st_mtime);
   1081 	hd->h_mtime_2[0] = CHR_WR_2(arcn->sb.st_mtime);
   1082 	hd->h_mtime_2[1] = CHR_WR_3(arcn->sb.st_mtime);
   1083 	t_timet = (time_t)(SHRT_EXT(hd->h_mtime_1));
   1084 	t_timet =  (t_timet << 16) | ((time_t)(SHRT_EXT(hd->h_mtime_2)));
   1085 	if (arcn->sb.st_mtime != t_timet)
   1086 		goto out;
   1087 	nsz = arcn->nlen + 1;
   1088 	hd->h_namesize[0] = CHR_WR_2(nsz);
   1089 	hd->h_namesize[1] = CHR_WR_3(nsz);
   1090 	if (nsz != (int)(SHRT_EXT(hd->h_namesize)))
   1091 		goto out;
   1092 
   1093 	/*
   1094 	 * write the header, the file name and padding as required.
   1095 	 */
   1096 	if ((wr_rdbuf(hdblk, (int)sizeof(HD_BCPIO)) < 0) ||
   1097 	    (wr_rdbuf(arcn->name, nsz) < 0) ||
   1098 	    (wr_skip((off_t)(BCPIO_PAD(sizeof(HD_BCPIO) + nsz))) < 0)) {
   1099 		tty_warn(1, "Could not write bcpio header for %s",
   1100 		    arcn->org_name);
   1101 		return(-1);
   1102 	}
   1103 
   1104 	/*
   1105 	 * if we have file data, tell the caller we are done
   1106 	 */
   1107 	if ((arcn->type == PAX_CTG) || (arcn->type == PAX_REG) ||
   1108 	    (arcn->type == PAX_HRG))
   1109 		return(0);
   1110 
   1111 	/*
   1112 	 * if we are not a link, tell the caller we are done, go to next file
   1113 	 */
   1114 	if (arcn->type != PAX_SLK)
   1115 		return(1);
   1116 
   1117 	/*
   1118 	 * write the link name, tell the caller we are done.
   1119 	 */
   1120 	if ((wr_rdbuf(arcn->ln_name, arcn->ln_nlen) < 0) ||
   1121 	    (wr_skip((off_t)(BCPIO_PAD(arcn->ln_nlen))) < 0)) {
   1122 		tty_warn(1,"Could not write bcpio link name for %s",
   1123 		    arcn->org_name);
   1124 		return(-1);
   1125 	}
   1126 	return(1);
   1127 
   1128     out:
   1129 	/*
   1130 	 * header field is out of range
   1131 	 */
   1132 	tty_warn(1,"Bcpio header field is too small for file %s",
   1133 	    arcn->org_name);
   1134 	return(1);
   1135 }
   1136