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tar.c
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/* $OpenBSD: tar.c,v 1.67 2018/09/13 12:33:43 millert Exp $ */
/* $NetBSD: tar.c,v 1.5 1995/03/21 09:07:49 cgd Exp $ */
/*-
* Copyright (c) 2006, 2012, 2016, 2017, 2019
* mirabilos <[email protected]>
* Copyright (c) 1992 Keith Muller.
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Keith Muller of the University of California, San Diego.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <ctype.h>
#include <errno.h>
#if HAVE_GRP_H
#include <grp.h>
#endif
#include <limits.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#if HAVE_STRINGS_H
#include <strings.h>
#endif
#include <unistd.h>
#include "pax.h"
#include "extern.h"
#include "tar.h"
__RCSID("$MirOS: src/bin/pax/tar.c,v 1.24 2019/02/23 22:39:25 tg Exp $");
/*
* Routines for reading, writing and header identify of various versions of tar
*/
static size_t expandname(char *, size_t, char **, const char *, size_t);
static u_long tar_chksm(char *, int);
static char *name_split(char *, int);
static int ul_oct(u_long, char *, int, int);
static int ull_oct(unsigned long long, char *, int, int);
#ifndef SMALL
static void tar_dbgfld(const char *, const char *, size_t);
static int rd_xheader(ARCHD *arcn, int, off_t);
#endif
static uid_t uid_nobody;
static uid_t uid_warn;
static gid_t gid_nobody;
static gid_t gid_warn;
/*
* Routines common to all versions of tar
*/
#ifndef SMALL
char tar_nodir; /* do not write dirs under old tar */
#endif
char *gnu_name_string; /* GNU ././@LongLink hackery name */
char *gnu_link_string; /* GNU ././@LongLink hackery link */
/*
* tar_endwr()
* add the tar trailer of two null blocks
* Return:
* 0 if ok, -1 otherwise (what wr_skip returns)
*/
int
tar_endwr(void)
{
return (wr_skip(NULLCNT * BLKMULT));
}
/*
* tar_endrd()
* no cleanup needed here, just return size of trailer (for append)
* Return:
* size of trailer (2 * BLKMULT)
*/
off_t
tar_endrd(void)
{
return (NULLCNT * BLKMULT);
}
/*
* tar_trail()
* Called to determine if a header block is a valid trailer. We are passed
* the block, the in_sync flag (which tells us we are in resync mode;
* looking for a valid header), and cnt (which starts at zero) which is
* used to count the number of empty blocks we have seen so far.
* Return:
* 0 if a valid trailer, -1 if not a valid trailer, or 1 if the block
* could never contain a header.
*/
int
tar_trail(ARCHD *ignore MKSH_A_UNUSED, char *buf, int in_resync, int *cnt)
{
int i;
/*
* look for all zero, trailer is two consecutive blocks of zero
*/
for (i = 0; i < BLKMULT; ++i) {
if (buf[i] != '\0')
break;
}
/*
* if not all zero it is not a trailer, but MIGHT be a header.
*/
if (i != BLKMULT)
return(-1);
/*
* When given a zero block, we must be careful!
* If we are not in resync mode, check for the trailer. Have to watch
* out that we do not mis-identify file data as the trailer, so we do
* NOT try to id a trailer during resync mode. During resync mode we
* might as well throw this block out since a valid header can NEVER be
* a block of all 0 (we must have a valid file name).
*/
if (!in_resync && (++*cnt >= NULLCNT))
return(0);
return(1);
}
/*
* ul_oct()
* convert an unsigned long to an octal string. many oddball field
* termination characters are used by the various versions of tar in the
* different fields. term selects which kind to use. str is '0' padded
* at the front to len. we are unable to use only one format as many old
* tar readers are very cranky about this.
* Return:
* 0 if the number fit into the string, -1 otherwise
*/
static int
ul_oct(u_long val, char *str, int len, int term)
{
char *pt;
/*
* term selects the appropriate character(s) for the end of the string
*/
pt = str + len - 1;
switch (term) {
case 3:
*pt-- = '\0';
break;
case 2:
*pt-- = ' ';
*pt-- = '\0';
break;
case 1:
*pt-- = ' ';
break;
case 0:
default:
*pt-- = '\0';
*pt-- = ' ';
break;
}
/*
* convert and blank pad if there is space
*/
while (pt >= str) {
*pt-- = '0' + (char)(val & 0x7);
val >>= 3;
if (val == 0)
break;
}
while (pt >= str)
*pt-- = '0';
if (val != 0)
return(-1);
return(0);
}
/*
* ull_oct()
* Convert an unsigned long long to an octal string. One of many oddball
* field termination characters are used by the various versions of tar
* in the different fields. term selects which kind to use. str is
* '0' padded at the front to len. We are unable to use only one format
* as many old tar readers are very cranky about this.
* Return:
* 0 if the number fit into the string, -1 otherwise
*/
static int
ull_oct(unsigned long long val, char *str, int len, int term)
{
char *pt;
/*
* term selects the appropriate character(s) for the end of the string
*/
pt = str + len - 1;
switch (term) {
case 3:
*pt-- = '\0';
break;
case 2:
*pt-- = ' ';
*pt-- = '\0';
break;
case 1:
*pt-- = ' ';
break;
case 0:
default:
*pt-- = '\0';
*pt-- = ' ';
break;
}
/*
* convert and blank pad if there is space
*/
while (pt >= str) {
*pt-- = '0' + (char)(val & 0x7);
val >>= 3;
if (val == 0)
break;
}
while (pt >= str)
*pt-- = '0';
if (val != 0)
return(-1);
return(0);
}
/*
* tar_chksm()
* calculate the checksum for a tar block counting the checksum field as
* all blanks (BLNKSUM is that value pre-calculated, the sum of 8 blanks).
* NOTE: we use len to short circuit summing 0's on write since we ALWAYS
* pad headers with 0.
* Return:
* unsigned long checksum
*/
static u_long
tar_chksm(char *blk, int len)
{
char *stop;
char *pt;
u_long chksm = BLNKSUM; /* initial value is checksum field sum */
/*
* add the part of the block before the checksum field
*/
pt = blk;
stop = blk + CHK_OFFSET;
while (pt < stop)
chksm += (u_long)(*pt++ & 0xff);
/*
* move past the checksum field and keep going, spec counts the
* checksum field as the sum of 8 blanks (which is pre-computed as
* BLNKSUM).
* ASSUMED: len is greater than CHK_OFFSET. (len is where our 0 padding
* starts, no point in summing zero's)
*/
pt += CHK_LEN;
stop = blk + len;
while (pt < stop)
chksm += (u_long)(*pt++ & 0xff);
return(chksm);
}
#ifndef SMALL
/*
* Routines for old BSD style tar (also made portable to sysV tar)
*/
/*
* tar_id()
* determine if a block given to us is a valid tar header (and not a USTAR
* header). We have to be on the lookout for those pesky blocks of all
* zero's.
* Return:
* 0 if a tar header, -1 otherwise
*/
int
tar_id(char *blk, int size)
{
HD_TAR *hd;
HD_USTAR *uhd;
if (size < BLKMULT)
return (-1);
hd = (HD_TAR *)blk;
uhd = (HD_USTAR *)blk;
/*
* check for block of NULs first, a simple and fast test, then make
* sure this is not a ustar header by looking for the ustar magic
* cookie. We should use TMAGLEN, but some USTAR archive programs are
* wrong and create archives missing the \0. Last we check the
* checksum. If this is ok we have to assume it is a valid header.
*/
if (hd->name[0] == '\0')
return (-1);
if (memcmp(uhd->magic, TMAGIC, TMAGLEN - 1) == 0)
return (-1);
if (asc_ul(hd->chksum, sizeof(hd->chksum), OCT) != tar_chksm(blk, BLKMULT))
return (-1);
force_one_volume = 1;
return (0);
}
/*
* tar_opt()
* handle tar format specific -o options
* Return:
* 0 if ok -1 otherwise
*/
int
tar_opt(void)
{
OPLIST *opt;
while ((opt = opt_next()) != NULL) {
if (strcmp(opt->name, TAR_OPTION) ||
strcmp(opt->value, TAR_NODIR)) {
paxwarn(1, "Unknown tar format -o option/value pair %s=%s",
opt->name, opt->value);
paxwarn(1,"%s=%s is the only supported tar format option",
TAR_OPTION, TAR_NODIR);
return(-1);
}
/*
* we only support one option, and only when writing
*/
if ((act != APPND) && (act != ARCHIVE)) {
paxwarn(1, "%s=%s is only supported when writing.",
opt->name, opt->value);
return(-1);
}
tar_nodir = 1;
}
return(0);
}
/*
* tar_rd()
* extract the values out of block already determined to be a tar header.
* store the values in the ARCHD parameter.
* Return:
* 0
*/
int
tar_rd(ARCHD *arcn, char *buf)
{
HD_TAR *hd;
unsigned long long val;
char *pt;
/*
* we only get proper sized buffers passed to us
*/
if (tar_id(buf, BLKMULT) < 0)
return(-1);
memset(arcn, 0, sizeof(*arcn));
arcn->org_name = arcn->name;
arcn->sb.st_nlink = 1;
/*
* copy out the name and values in the stat buffer
*/
hd = (HD_TAR *)buf;
if (hd->linkflag != LONGLINKTYPE && hd->linkflag != LONGNAMETYPE) {
arcn->nlen = expandname(arcn->name, sizeof(arcn->name),
&gnu_name_string, hd->name, sizeof(hd->name));
arcn->ln_nlen = expandname(arcn->ln_name, sizeof(arcn->ln_name),
&gnu_link_string, hd->linkname, sizeof(hd->linkname));
}
arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode,sizeof(hd->mode),OCT) &
0xfff);
arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT);
arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT);
arcn->sb.st_size = (off_t)asc_ull(hd->size, sizeof(hd->size), OCT);
val = asc_ull(hd->mtime, sizeof(hd->mtime), OCT);
if (val > MAX_TIME_T)
arcn->sb.st_mtime = INT_MAX; /* XXX 2038 */
else
arcn->sb.st_mtime = val;
arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
/*
* have to look at the last character, it may be a '/' and that is used
* to encode this as a directory
*/
pt = arcn->nlen > 0 ? &(arcn->name[arcn->nlen - 1]) : NULL;
arcn->pad = 0;
arcn->skip = 0;
switch (hd->linkflag) {
case SYMTYPE:
/*
* symbolic link, need to get the link name and set the type in
* the st_mode so -v printing will look correct.
*/
arcn->type = PAX_SLK;
arcn->sb.st_mode |= S_IFLNK;
break;
case LNKTYPE:
/*
* hard link, need to get the link name, set the type in the
* st_mode and st_nlink so -v printing will look better.
*/
arcn->type = PAX_HLK;
arcn->sb.st_nlink = 2;
/*
* no idea of what type this thing really points at, but
* we set something for printing only.
*/
arcn->sb.st_mode |= S_IFREG;
break;
case LONGLINKTYPE:
case LONGNAMETYPE:
/*
* GNU long link/file; we tag these here and let the
* pax internals deal with it -- too ugly otherwise.
*/
arcn->type =
hd->linkflag == LONGLINKTYPE ? PAX_GLL : PAX_GLF;
arcn->pad = TAR_PAD(arcn->sb.st_size);
arcn->skip = arcn->sb.st_size;
break;
case DIRTYPE:
/*
* It is a directory, set the mode for -v printing
*/
arcn->type = PAX_DIR;
arcn->sb.st_mode |= S_IFDIR;
arcn->sb.st_nlink = 2;
break;
case AREGTYPE:
case REGTYPE:
default:
/*
* If we have a trailing / this is a directory and NOT a file.
*/
arcn->ln_name[0] = '\0';
arcn->ln_nlen = 0;
if (pt && *pt == '/') {
/*
* it is a directory, set the mode for -v printing
*/
arcn->type = PAX_DIR;
arcn->sb.st_mode |= S_IFDIR;
arcn->sb.st_nlink = 2;
} else {
/*
* have a file that will be followed by data. Set the
* skip value to the size field and calculate the size
* of the padding.
*/
arcn->type = PAX_REG;
arcn->sb.st_mode |= S_IFREG;
arcn->pad = TAR_PAD(arcn->sb.st_size);
arcn->skip = arcn->sb.st_size;
}
break;
}
/*
* strip off any trailing slash.
*/
if (pt && *pt == '/') {
*pt = '\0';
--arcn->nlen;
}
return (0);
}
/*
* tar_wr()
* write a tar header for the file specified in the ARCHD to the archive.
* Have to check for file types that cannot be stored and file names that
* are too long. Be careful of the term (last arg) to ul_oct, each field
* of tar has it own spec for the termination character(s).
* ASSUMED: space after header in header block is zero filled
* Return:
* 0 if file has data to be written after the header, 1 if file has NO
* data to write after the header, -1 if archive write failed
*/
int
tar_wr(ARCHD *arcn)
{
HD_TAR *hd;
int len;
char hdblk[sizeof(HD_TAR)];
/*
* check for those filesystem types which tar cannot store
*/
switch (arcn->type) {
case PAX_DIR:
#ifndef SMALL
/*
* user asked that dirs not be written to the archive
*/
if (tar_nodir)
return(1);
#endif
break;
case PAX_CHR:
paxwarn(1, "%s cannot archive a %s %s",
"tar", "character device", arcn->org_name);
return (1);
case PAX_BLK:
paxwarn(1, "%s cannot archive a %s %s",
"tar", "block device", arcn->org_name);
return (1);
case PAX_SCK:
paxwarn(1, "%s cannot archive a %s %s",
"tar", "socket", arcn->org_name);
return (1);
case PAX_FIF:
paxwarn(1, "%s cannot archive a %s %s",
"tar", "FIFO", arcn->org_name);
return (1);
case PAX_SLK:
case PAX_HLK:
case PAX_HRG:
if ((size_t)arcn->ln_nlen > sizeof(hd->linkname)) {
paxwarn(1, "%s name too long for %s %s",
"Link", "tar", arcn->ln_name);
return (1);
}
break;
case PAX_REG:
case PAX_CTG:
default:
break;
}
/*
* check file name len, remember extra char for dirs (the / at the end)
*/
len = arcn->nlen;
if (arcn->type == PAX_DIR)
++len;
if ((size_t)len > sizeof(hd->name)) {
paxwarn(1, "%s name too long for %s %s",
"File", "tar", arcn->name);
return (1);
}
/*
* Copy the data out of the ARCHD into the tar header based on the type
* of the file. Remember, many tar readers want all fields to be
* padded with zero so we zero the header first. We then set the
* linkflag field (type), the linkname, the size, and set the padding
* (if any) to be added after the file data (0 for all other types,
* as they only have a header).
*/
memset(hdblk, 0, sizeof(hdblk));
hd = (HD_TAR *)hdblk;
fieldcpy(hd->name, sizeof(hd->name), arcn->name, sizeof(arcn->name));
arcn->pad = 0;
if (arcn->type == PAX_DIR) {
/*
* directories are the same as files, except have a filename
* that ends with a /, we add the slash here. No data follows
* dirs, so no pad.
*/
hd->linkflag = AREGTYPE;
hd->name[len-1] = '/';
if (ul_oct(0, hd->size, sizeof(hd->size), 1))
goto out;
} else if (arcn->type == PAX_SLK) {
/*
* no data follows this file, so no pad
*/
hd->linkflag = SYMTYPE;
fieldcpy(hd->linkname, sizeof(hd->linkname), arcn->ln_name,
sizeof(arcn->ln_name));
if (ul_oct(0, hd->size, sizeof(hd->size), 1))
goto out;
} else if (PAX_IS_HARDLINK(arcn->type)) {
/*
* no data follows this file, so no pad
*/
hd->linkflag = LNKTYPE;
fieldcpy(hd->linkname, sizeof(hd->linkname), arcn->ln_name,
sizeof(arcn->ln_name));
if (ul_oct(0, hd->size, sizeof(hd->size), 1))
goto out;
} else {
/*
* data follows this file, so set the pad
*/
hd->linkflag = AREGTYPE;
if (ull_oct(arcn->sb.st_size, hd->size, sizeof(hd->size), 1)) {
paxwarn(1, "File is too large for %s format %s",
"tar", arcn->org_name);
return (1);
}
arcn->pad = TAR_PAD(arcn->sb.st_size);
}
/*
* copy those fields that are independent of the type
*/
if (ul_oct(arcn->sb.st_mode, hd->mode, sizeof(hd->mode), 0) ||
ull_oct(arcn->sb.st_mtime < 0 ? 0 : arcn->sb.st_mtime, hd->mtime,
sizeof(hd->mtime), 1) ||
ul_oct(arcn->sb.st_uid, hd->uid, sizeof(hd->uid), 0) ||
ul_oct(arcn->sb.st_gid, hd->gid, sizeof(hd->gid), 0))
goto out;
/*
* calculate and add the checksum, then write the header. A return of
* 0 tells the caller to now write the file data, 1 says no data needs
* to be written
*/
if (ul_oct(tar_chksm(hdblk, sizeof(HD_TAR)), hd->chksum,
sizeof(hd->chksum), 3))
goto out;
if (wr_rdbuf(hdblk, sizeof(HD_TAR)) < 0)
return(-1);
if (wr_skip(BLKMULT - sizeof(HD_TAR)) < 0)
return(-1);
if (PAX_IS_REG(arcn->type))
return(0);
return(1);
out:
/*
* header field is out of range
*/
paxwarn(1, "%s header field is too small for file %s",
"tar", arcn->org_name);
return (1);
}
#endif
/*
* Routines for POSIX ustar
*/
/*
* ustar_strd()
* initialization for ustar read
* Return:
* 0 if ok, -1 otherwise
*/
int
ustar_strd(void)
{
#if !HAVE_UGID_FROM_UG
if ((usrtb_start() < 0) || (grptb_start() < 0))
return(-1);
#endif
return(0);
}
/*
* ustar_stwr()
* initialization for ustar write
* Return:
* 0 if ok, -1 otherwise
*/
int
ustar_stwr(int is_app MKSH_A_UNUSED)
{
#if !HAVE_UG_FROM_UGID
if ((uidtb_start() < 0) || (gidtb_start() < 0))
return(-1);
#endif
return(0);
}
/*
* ustar_id()
* determine if a block given to us is a valid ustar header. We have to
* be on the lookout for those pesky blocks of all zero's
* Return:
* 0 if a ustar header, -1 otherwise
*/
int
ustar_id(char *blk, int size)
{
HD_USTAR *hd;
if (size < BLKMULT)
return (-1);
hd = (HD_USTAR *)blk;
/*
* check for block of NULs first, a simple and fast test, then check
* ustar magic cookie. We should use TMAGLEN, but some USTAR archive
* programs are fouled up and create archives missing the \0. Last we
* check the checksum. If ok we have to assume it is a valid header.
*/
if (hd->prefix[0] == '\0' && hd->name[0] == '\0')
return (-1);
if (memcmp(hd->magic, TMAGIC, TMAGLEN - 1) != 0)
return (-1);
if (asc_ul(hd->chksum, sizeof(hd->chksum), OCT) != tar_chksm(blk, BLKMULT))
return (-1);
return (0);
}
/*
* ustar_rd()
* extract the values out of block already determined to be a ustar header.
* store the values in the ARCHD parameter.
* Return:
* 0
*/
int
ustar_rd(ARCHD *arcn, char *buf)
{
HD_USTAR *hd = (HD_USTAR *)buf;
char *dest;
int cnt = 0;
dev_t devmajor;
dev_t devminor;
unsigned long long val;
/*
* we only get proper sized buffers
*/
if (ustar_id(buf, BLKMULT) < 0)
return(-1);
#ifndef SMALL
reset:
#endif
memset(arcn, 0, sizeof(*arcn));
arcn->org_name = arcn->name;
arcn->sb.st_nlink = 1;
#ifndef SMALL
/* Process Extended headers. */
if (hd->typeflag == XHDRTYPE || hd->typeflag == GHDRTYPE) {
if (rd_xheader(arcn, hd->typeflag == GHDRTYPE,
(off_t)asc_ul(hd->size, sizeof(hd->size), OCT)) < 0)
return (-1);
/* Update and check the ustar header. */
if (rd_wrbuf(buf, BLKMULT) != BLKMULT)
return (-1);
if (ustar_id(buf, BLKMULT) < 0)
return(-1);
/* if the next block is another extension, reset the values */
if (hd->typeflag == XHDRTYPE || hd->typeflag == GHDRTYPE)
goto reset;
}
#endif
if (!arcn->nlen) {
/*
* See if the filename is split into two parts. if, so join
* the parts. We copy the prefix first and add a / between
* the prefix and name.
*/
dest = arcn->name;
if (*(hd->prefix) != '\0') {
cnt = fieldcpy(dest, sizeof(arcn->name) - 1,
hd->prefix, sizeof(hd->prefix));
dest += cnt;
*dest++ = '/';
cnt++;
} else
cnt = 0;
if (hd->typeflag != LONGLINKTYPE &&
hd->typeflag != LONGNAMETYPE) {
arcn->nlen = cnt + expandname(dest,
sizeof(arcn->name) - cnt, &gnu_name_string,
hd->name, sizeof(hd->name));
}
}
if (!arcn->ln_nlen &&
hd->typeflag != LONGLINKTYPE && hd->typeflag != LONGNAMETYPE) {
arcn->ln_nlen = expandname(arcn->ln_name, sizeof(arcn->ln_name),
&gnu_link_string, hd->linkname, sizeof(hd->linkname));
}
/*
* follow the spec to the letter. we should only have mode bits, strip
* off all other crud we may be passed.
*/
arcn->sb.st_mode = (mode_t)(asc_ul(hd->mode, sizeof(hd->mode), OCT) &
0xfff);
arcn->sb.st_size = (off_t)asc_ull(hd->size, sizeof(hd->size), OCT);
val = asc_ull(hd->mtime, sizeof(hd->mtime), OCT);
if (val > MAX_TIME_T)
arcn->sb.st_mtime = INT_MAX; /* XXX 2038 */
else
arcn->sb.st_mtime = val;
arcn->sb.st_ctime = arcn->sb.st_atime = arcn->sb.st_mtime;
/*
* If we can find the ascii names for gname and uname in the password
* and group files we will use the uid's and gid they bind. Otherwise
* we use the uid and gid values stored in the header. (This is what
* the posix spec wants).
*/
hd->gname[sizeof(hd->gname) - 1] = '\0';
if ((anonarch & ANON_NUMID) ||
gid_name(hd->gname, &(arcn->sb.st_gid)) < 0)
arcn->sb.st_gid = (gid_t)asc_ul(hd->gid, sizeof(hd->gid), OCT);
hd->uname[sizeof(hd->uname) - 1] = '\0';
if ((anonarch & ANON_NUMID) ||
uid_name(hd->uname, &(arcn->sb.st_uid)) < 0)
arcn->sb.st_uid = (uid_t)asc_ul(hd->uid, sizeof(hd->uid), OCT);
/*
* set the defaults, these may be changed depending on the file type
*/
arcn->pad = 0;
arcn->skip = 0;
arcn->sb.st_rdev = (dev_t)0;
/*
* set the mode and PAX type according to the typeflag in the header
*/
switch (hd->typeflag) {
case FIFOTYPE:
arcn->type = PAX_FIF;
arcn->sb.st_mode |= S_IFIFO;
break;
case DIRTYPE:
arcn->type = PAX_DIR;
arcn->sb.st_mode |= S_IFDIR;
arcn->sb.st_nlink = 2;
/*
* Some programs that create ustar archives append a '/'
* to the pathname for directories. This clearly violates
* ustar specs, but we will silently strip it off anyway.
*/
if (arcn->name[arcn->nlen - 1] == '/')
arcn->name[--arcn->nlen] = '\0';
break;
case BLKTYPE:
case CHRTYPE:
/*
* this type requires the rdev field to be set.
*/
if (hd->typeflag == BLKTYPE) {
arcn->type = PAX_BLK;
arcn->sb.st_mode |= S_IFBLK;
} else {
arcn->type = PAX_CHR;
arcn->sb.st_mode |= S_IFCHR;
}
devmajor = (dev_t)asc_ul(hd->devmajor,sizeof(hd->devmajor),OCT);
devminor = (dev_t)asc_ul(hd->devminor,sizeof(hd->devminor),OCT);
arcn->sb.st_rdev = TODEV(devmajor, devminor);
break;
case SYMTYPE:
case LNKTYPE:
if (hd->typeflag == SYMTYPE) {
arcn->type = PAX_SLK;
arcn->sb.st_mode |= S_IFLNK;
} else {
arcn->type = PAX_HLK;
/*
* so printing looks better
*/
arcn->sb.st_mode |= S_IFREG;
arcn->sb.st_nlink = 2;
}
break;
case LONGLINKTYPE:
case LONGNAMETYPE:
/*
* GNU long link/file; we tag these here and let the
* pax internals deal with it -- too ugly otherwise.
*/
arcn->type =
hd->typeflag == LONGLINKTYPE ? PAX_GLL : PAX_GLF;
arcn->pad = TAR_PAD(arcn->sb.st_size);
arcn->skip = arcn->sb.st_size;
break;
case CONTTYPE:
case AREGTYPE:
case REGTYPE:
default:
/*
* these types have file data that follows. Set the skip and
* pad fields.
*/
arcn->type = PAX_REG;
arcn->pad = TAR_PAD(arcn->sb.st_size);
arcn->skip = arcn->sb.st_size;
arcn->sb.st_mode |= S_IFREG;
break;
}
return(0);
}
/*
* ustar_wr()
* write a ustar header for the file specified in the ARCHD to the archive
* Have to check for file types that cannot be stored and file names that
* are too long. Be careful of the term (last arg) to ul_oct, we only use
* '\0' for the termination character (this is different than picky tar)
* ASSUMED: space after header in header block is zero filled
* Return:
* 0 if file has data to be written after the header, 1 if file has NO
* data to write after the header, -1 if archive write failed
*/
int
ustar_wr(ARCHD *arcn)
{
HD_USTAR *hd;
const char *name;
char *pt, hdblk[sizeof(HD_USTAR)];
u_long t_uid, t_gid;
time_t t_mtime;
anonarch_init();
/*
* check for those filesystem types ustar cannot store
*/
if (arcn->type == PAX_SCK) {
paxwarn(1, "%s cannot archive a %s %s",
"ustar", "socket", arcn->org_name);
return (1);
}
#ifndef SMALL
/*
* user asked that dirs not be written to the archive
*/
if (arcn->type == PAX_DIR && tar_nodir)
return (1);
#endif
/*
* check the length of the linkname
*/
if (PAX_IS_LINK(arcn->type) &&
((size_t)arcn->ln_nlen > sizeof(hd->linkname))) {
paxwarn(1, "%s name too long for %s %s",
"Link", "ustar", arcn->ln_name);
return (1);
}
/*
* if -M gslash: append a slash if directory