Commit message: Fix memory leak in read_header

Bug reported in https://savannah.gnu.org/bugs/?59897

* src/list.c (read_header): Don't return directly from the loop.
Instead set the status and break.  Return the status.  Free
next_long_name and next_long_link before returning.
CVE: CVE-2021-20193
CWE: CWE-125
Vulnerability description: A flaw was found in the src/list.c of tar 1.33 and earlier. This flaw allows an attacker who can submit a crafted input file to tar to cause uncontrolled consumption of memory. The highest threat from this vulnerability is to system availability.

Project: tar

major_from_header (const char *p, size_t s)
{
  return from_header (p, s, "major_t",
		      TYPE_MINIMUM (major_t), TYPE_MAXIMUM (major_t),
		      false, false);
}

Project: tar

uintmax_from_header (const char *p, size_t s)
{
  return from_header (p, s, "uintmax_t", 0, UINTMAX_MAX, false, false);
}

Project: tar

simple_print_header (struct tar_stat_info *st, union block *blk,
		     off_t block_ordinal)
{
  char modes[12];
  char const *time_stamp;
  int time_stamp_len;
  char *temp_name;

  /* These hold formatted ints.  */
  char uform[max (INT_BUFSIZE_BOUND (intmax_t), UINTMAX_STRSIZE_BOUND)];
  char gform[sizeof uform];
  char *user, *group;
  char size[2 * UINTMAX_STRSIZE_BOUND];
  				/* holds formatted size or major,minor */
  char uintbuf[UINTMAX_STRSIZE_BOUND];
  int pad;
  int sizelen;

  if (show_transformed_names_option)
    temp_name = st->file_name ? st->file_name : st->orig_file_name;
  else
    temp_name = st->orig_file_name ? st->orig_file_name : st->file_name;

  if (block_number_option)
    {
      char buf[UINTMAX_STRSIZE_BOUND];
      if (block_ordinal < 0)
	block_ordinal = current_block_ordinal ();
      block_ordinal -= recent_long_name_blocks;
      block_ordinal -= recent_long_link_blocks;
      fprintf (stdlis, _("block %s: "),
	       STRINGIFY_BIGINT (block_ordinal, buf));
    }

  if (verbose_option <= 1)
    {
      /* Just the fax, mam.  */
      fputs (quotearg (temp_name), stdlis);
      if (show_transformed_names_option && st->had_trailing_slash)
	fputc ('/', stdlis);
      fputc ('\n', stdlis);
    }
  else
    {
      /* File type and modes.  */

      modes[0] = '?';
      switch (blk->header.typeflag)
	{
	case GNUTYPE_VOLHDR:
	  volume_label_printed = true;
	  modes[0] = 'V';
	  break;

	case GNUTYPE_MULTIVOL:
	  modes[0] = 'M';
	  break;

	case GNUTYPE_LONGNAME:
	case GNUTYPE_LONGLINK:
	  modes[0] = 'L';
	  ERROR ((0, 0, _("Unexpected long name header")));
	  break;

	case GNUTYPE_SPARSE:
	case REGTYPE:
	case AREGTYPE:
	  modes[0] = st->had_trailing_slash ? 'd' : '-';
	  break;
	case LNKTYPE:
	  modes[0] = 'h';
	  break;
	case GNUTYPE_DUMPDIR:
	  modes[0] = 'd';
	  break;
	case DIRTYPE:
	  modes[0] = 'd';
	  break;
	case SYMTYPE:
	  modes[0] = 'l';
	  break;
	case BLKTYPE:
	  modes[0] = 'b';
	  break;
	case CHRTYPE:
	  modes[0] = 'c';
	  break;
	case FIFOTYPE:
	  modes[0] = 'p';
	  break;
	case CONTTYPE:
	  modes[0] = 'C';
	  break;
	}

      pax_decode_mode (st->stat.st_mode, modes + 1);

      /* extended attributes:  GNU `ls -l'-like preview */
      xattrs_print_char (st, modes + 10);

      /* Time stamp.  */

      time_stamp = tartime (st->mtime, full_time_option);
      time_stamp_len = strlen (time_stamp);
      if (datewidth < time_stamp_len)
	datewidth = time_stamp_len;

      /* User and group names.  */

      if (st->uname
	  && st->uname[0]
	  && current_format != V7_FORMAT
	  && !numeric_owner_option)
	user = st->uname;
      else
	user = STRINGIFY_BIGINT (st->stat.st_uid, uform);

      if (st->gname
	  && st->gname[0]
	  && current_format != V7_FORMAT
	  && !numeric_owner_option)
	group = st->gname;
      else
	group = STRINGIFY_BIGINT (st->stat.st_gid, gform);

      /* Format the file size or major/minor device numbers.  */

      switch (blk->header.typeflag)
	{
	case CHRTYPE:
	case BLKTYPE:
	  strcpy (size,
		  STRINGIFY_BIGINT (major (st->stat.st_rdev), uintbuf));
	  strcat (size, ",");
	  strcat (size,
		  STRINGIFY_BIGINT (minor (st->stat.st_rdev), uintbuf));
	  break;

	default:
	  /* st->stat.st_size keeps stored file size */
	  strcpy (size, STRINGIFY_BIGINT (st->stat.st_size, uintbuf));
	  break;
	}

      /* Figure out padding and print the whole line.  */

      sizelen = strlen (size);
      pad = strlen (user) + 1 + strlen (group) + 1 + sizelen;
      if (pad > ugswidth)
	ugswidth = pad;

      fprintf (stdlis, "%s %s/%s %*s %-*s",
	       modes, user, group, ugswidth - pad + sizelen, size,
	       datewidth, time_stamp);

      fprintf (stdlis, " %s", quotearg (temp_name));
      if (show_transformed_names_option && st->had_trailing_slash)
	fputc ('/', stdlis);

      switch (blk->header.typeflag)
	{
	case SYMTYPE:
	  fprintf (stdlis, " -> %s\n", quotearg (st->link_name));
	  break;

	case LNKTYPE:
	  fprintf (stdlis, _(" link to %s\n"), quotearg (st->link_name));
	  break;

	default:
	  {
	    char type_string[2];
	    type_string[0] = blk->header.typeflag;
	    type_string[1] = '\0';
	    fprintf (stdlis, _(" unknown file type %s\n"),
		     quote (type_string));
	  }
	  break;

	case AREGTYPE:
	case REGTYPE:
	case GNUTYPE_SPARSE:
	case CHRTYPE:
	case BLKTYPE:
	case DIRTYPE:
	case FIFOTYPE:
	case CONTTYPE:
	case GNUTYPE_DUMPDIR:
	  putc ('\n', stdlis);
	  break;

	case GNUTYPE_LONGLINK:
	  fprintf (stdlis, _("--Long Link--\n"));
	  break;

	case GNUTYPE_LONGNAME:
	  fprintf (stdlis, _("--Long Name--\n"));
	  break;

	case GNUTYPE_VOLHDR:
	  fprintf (stdlis, _("--Volume Header--\n"));
	  break;

	case GNUTYPE_MULTIVOL:
	  strcpy (size,
		  STRINGIFY_BIGINT
		  (UINTMAX_FROM_HEADER (blk->oldgnu_header.offset),
		   uintbuf));
	  fprintf (stdlis, _("--Continued at byte %s--\n"), size);
	  break;
	}
    }
  fflush (stdlis);
  xattrs_print (st);
}

Project: tar

minor_from_header (const char *p, size_t s)
{
  return from_header (p, s, "minor_t",
		      TYPE_MINIMUM (minor_t), TYPE_MAXIMUM (minor_t),
		      false, false);
}

Project: tar

tartime (struct timespec t, bool full_time)
{
  enum { fraclen = sizeof ".FFFFFFFFF" - 1 };
  static char buffer[max (UINTMAX_STRSIZE_BOUND + 1,
			  INT_STRLEN_BOUND (int) + 16)
		     + fraclen];
  struct tm *tm;
  time_t s = t.tv_sec;
  int ns = t.tv_nsec;
  bool negative = s < 0;
  char *p;

  if (negative && ns != 0)
    {
      s++;
      ns = 1000000000 - ns;
    }

  tm = utc_option ? gmtime (&s) : localtime (&s);
  if (tm)
    {
      if (full_time)
	{
	  strftime (buffer, sizeof buffer, "%Y-%m-%d %H:%M:%S", tm);
	  code_ns_fraction (ns, buffer + strlen (buffer));
	}
      else
	strftime (buffer, sizeof buffer, "%Y-%m-%d %H:%M", tm);
      return buffer;
    }

  /* The time stamp cannot be broken down, most likely because it
     is out of range.  Convert it as an integer,
     right-adjusted in a field with the same width as the usual
     4-year ISO time format.  */
  p = umaxtostr (negative ? - (uintmax_t) s : s,
		 buffer + sizeof buffer - UINTMAX_STRSIZE_BOUND - fraclen);
  if (negative)
    *--p = '-';
  while ((buffer + sizeof buffer - sizeof "YYYY-MM-DD HH:MM"
	  + (full_time ? sizeof ":SS.FFFFFFFFF" - 1 : 0))
	 < p)
    *--p = ' ';
  if (full_time)
    code_ns_fraction (ns, buffer + sizeof buffer - 1 - fraclen);
  return p;
}

Project: tar

skip_member (void)
{
  if (!current_stat_info.skipped)
    {
      char save_typeflag = current_header->header.typeflag;
      set_next_block_after (current_header);

      mv_begin_read (&current_stat_info);

      if (current_stat_info.is_sparse)
	sparse_skip_file (&current_stat_info);
      else if (save_typeflag != DIRTYPE)
	skip_file (current_stat_info.stat.st_size);

      mv_end ();
    }
}

Project: tar

mode_from_header (const char *p, size_t s, bool *hbits)
{
  intmax_t u = from_header (p, s, "mode_t",
			    INTMAX_MIN, UINTMAX_MAX,
			    false, false);
  mode_t mode = ((u & TSUID ? S_ISUID : 0)
		 | (u & TSGID ? S_ISGID : 0)
		 | (u & TSVTX ? S_ISVTX : 0)
		 | (u & TUREAD ? S_IRUSR : 0)
		 | (u & TUWRITE ? S_IWUSR : 0)
		 | (u & TUEXEC ? S_IXUSR : 0)
		 | (u & TGREAD ? S_IRGRP : 0)
		 | (u & TGWRITE ? S_IWGRP : 0)
		 | (u & TGEXEC ? S_IXGRP : 0)
		 | (u & TOREAD ? S_IROTH : 0)
		 | (u & TOWRITE ? S_IWOTH : 0)
		 | (u & TOEXEC ? S_IXOTH : 0));
  *hbits = (u & ~07777) != 0;
  return mode;
}

Project: tar

read_and (void (*do_something) (void))
{
  enum read_header status = HEADER_STILL_UNREAD;
  enum read_header prev_status;
  struct timespec mtime;

  base64_init ();
  name_gather ();

  open_archive (ACCESS_READ);
  do
    {
      prev_status = status;
      tar_stat_destroy (&current_stat_info);

      status = read_header (&current_header, &current_stat_info,
                            read_header_auto);
      switch (status)
	{
	case HEADER_STILL_UNREAD:
	case HEADER_SUCCESS_EXTENDED:
	  abort ();

	case HEADER_SUCCESS:

	  /* Valid header.  We should decode next field (mode) first.
	     Ensure incoming names are null terminated.  */
	  decode_header (current_header, &current_stat_info,
			 &current_format, 1);
	  if (! name_match (current_stat_info.file_name)
	      || (TIME_OPTION_INITIALIZED (newer_mtime_option)
		  /* FIXME: We get mtime now, and again later; this causes
		     duplicate diagnostics if header.mtime is bogus.  */
		  && ((mtime.tv_sec
		       = TIME_FROM_HEADER (current_header->header.mtime)),
		      /* FIXME: Grab fractional time stamps from
			 extended header.  */
		      mtime.tv_nsec = 0,
		      current_stat_info.mtime = mtime,
		      OLDER_TAR_STAT_TIME (current_stat_info, m)))
	      || excluded_name (current_stat_info.file_name,
				current_stat_info.parent))
	    {
	      switch (current_header->header.typeflag)
		{
		case GNUTYPE_VOLHDR:
		case GNUTYPE_MULTIVOL:
		  break;

		case DIRTYPE:
		  if (show_omitted_dirs_option)
		    WARN ((0, 0, _("%s: Omitting"),
			   quotearg_colon (current_stat_info.file_name)));
		  FALLTHROUGH;
		default:
		  skip_member ();
		  continue;
		}
	    }

	  transform_stat_info (current_header->header.typeflag,
			       &current_stat_info);
	  (*do_something) ();
	  continue;

	case HEADER_ZERO_BLOCK:
	  if (block_number_option)
	    {
	      char buf[UINTMAX_STRSIZE_BOUND];
	      fprintf (stdlis, _("block %s: ** Block of NULs **\n"),
		       STRINGIFY_BIGINT (current_block_ordinal (), buf));
	    }

	  set_next_block_after (current_header);

	  if (!ignore_zeros_option)
	    {
	      char buf[UINTMAX_STRSIZE_BOUND];

	      status = read_header (&current_header, &current_stat_info,
	                            read_header_auto);
	      if (status == HEADER_ZERO_BLOCK)
		break;
	      WARNOPT (WARN_ALONE_ZERO_BLOCK,
		       (0, 0, _("A lone zero block at %s"),
			STRINGIFY_BIGINT (current_block_ordinal (), buf)));
	      break;
	    }
	  status = prev_status;
	  continue;

	case HEADER_END_OF_FILE:
	  if (block_number_option)
	    {
	      char buf[UINTMAX_STRSIZE_BOUND];
	      fprintf (stdlis, _("block %s: ** End of File **\n"),
		       STRINGIFY_BIGINT (current_block_ordinal (), buf));
	    }
	  break;

	case HEADER_FAILURE:
	  /* If the previous header was good, tell them that we are
	     skipping bad ones.  */
	  set_next_block_after (current_header);
	  switch (prev_status)
	    {
	    case HEADER_STILL_UNREAD:
	      ERROR ((0, 0, _("This does not look like a tar archive")));
	      FALLTHROUGH;
	    case HEADER_ZERO_BLOCK:
	    case HEADER_SUCCESS:
	      if (block_number_option)
		{
		  char buf[UINTMAX_STRSIZE_BOUND];
		  off_t block_ordinal = current_block_ordinal ();
		  block_ordinal -= recent_long_name_blocks;
		  block_ordinal -= recent_long_link_blocks;
		  fprintf (stdlis, _("block %s: "),
			   STRINGIFY_BIGINT (block_ordinal, buf));
		}
	      ERROR ((0, 0, _("Skipping to next header")));
	      break;

	    case HEADER_END_OF_FILE:
	    case HEADER_FAILURE:
	      /* We are in the middle of a cascade of errors.  */
	      break;

	    case HEADER_SUCCESS_EXTENDED:
	      abort ();
	    }
	  continue;
	}
      break;
    }
  while (!all_names_found (&current_stat_info));

  close_archive ();
  names_notfound ();		/* print names not found */
}

Project: tar

from_header (char const *where0, size_t digs, char const *type,
	     intmax_t minval, uintmax_t maxval,
	     bool octal_only, bool silent)
{
  uintmax_t value;
  uintmax_t uminval = minval;
  uintmax_t minus_minval = - uminval;
  char const *where = where0;
  char const *lim = where + digs;
  bool negative = false;

  /* Accommodate buggy tar of unknown vintage, which outputs leading
     NUL if the previous field overflows.  */
  where += !*where;

  /* Accommodate older tars, which output leading spaces.  */
  for (;;)
    {
      if (where == lim)
	{
	  if (type && !silent)
	    ERROR ((0, 0,
		    /* TRANSLATORS: %s is type of the value (gid_t, uid_t,
		       etc.) */
		    _("Blanks in header where numeric %s value expected"),
		    type));
	  return -1;
	}
      if (!isspace ((unsigned char) *where))
	break;
      where++;
    }

  value = 0;
  if (ISODIGIT (*where))
    {
      char const *where1 = where;
      bool overflow = false;

      for (;;)
	{
	  value += *where++ - '0';
	  if (where == lim || ! ISODIGIT (*where))
	    break;
	  overflow |= value != (value << LG_8 >> LG_8);
	  value <<= LG_8;
	}

      /* Parse the output of older, unportable tars, which generate
         negative values in two's complement octal.  If the leading
         nonzero digit is 1, we can't recover the original value
         reliably; so do this only if the digit is 2 or more.  This
         catches the common case of 32-bit negative time stamps.  */
      if ((overflow || maxval < value) && '2' <= *where1 && type)
	{
	  /* Compute the negative of the input value, assuming two's
	     complement.  */
	  int digit = (*where1 - '0') | 4;
	  overflow = 0;
	  value = 0;
	  where = where1;
	  for (;;)
	    {
	      value += 7 - digit;
	      where++;
	      if (where == lim || ! ISODIGIT (*where))
		break;
	      digit = *where - '0';
	      overflow |= value != (value << LG_8 >> LG_8);
	      value <<= LG_8;
	    }
	  value++;
	  overflow |= !value;

	  if (!overflow && value <= minus_minval)
	    {
	      if (!silent)
		WARN ((0, 0,
		       /* TRANSLATORS: Second %s is a type name (gid_t,uid_t,etc.) */
		       _("Archive octal value %.*s is out of %s range; assuming two's complement"),
		       (int) (where - where1), where1, type));
	      negative = true;
	    }
	}

      if (overflow)
	{
	  if (type && !silent)
	    ERROR ((0, 0,
		    /* TRANSLATORS: Second %s is a type name (gid_t,uid_t,etc.) */
		    _("Archive octal value %.*s is out of %s range"),
		    (int) (where - where1), where1, type));
	  return -1;
	}
    }
  else if (octal_only)
    {
      /* Suppress the following extensions.  */
    }
  else if (*where == '-' || *where == '+')
    {
      /* Parse base-64 output produced only by tar test versions
	 1.13.6 (1999-08-11) through 1.13.11 (1999-08-23).
	 Support for this will be withdrawn in future releases.  */
      int dig;
      if (!silent)
	{
	  static bool warned_once;
	  if (! warned_once)
	    {
	      warned_once = true;
	      WARN ((0, 0, _("Archive contains obsolescent base-64 headers")));
	    }
	}
      negative = *where++ == '-';
      while (where != lim
	     && (dig = base64_map[(unsigned char) *where]) < 64)
	{
	  if (value << LG_64 >> LG_64 != value)
	    {
	      char *string = alloca (digs + 1);
	      memcpy (string, where0, digs);
	      string[digs] = '\0';
	      if (type && !silent)
		ERROR ((0, 0,
			_("Archive signed base-64 string %s is out of %s range"),
			quote (string), type));
	      return -1;
	    }
	  value = (value << LG_64) | dig;
	  where++;
	}
    }
  else if (*where == '\200' /* positive base-256 */
	   || *where == '\377' /* negative base-256 */)
    {
      /* Parse base-256 output.  A nonnegative number N is
	 represented as (256**DIGS)/2 + N; a negative number -N is
	 represented as (256**DIGS) - N, i.e. as two's complement.
	 The representation guarantees that the leading bit is
	 always on, so that we don't confuse this format with the
	 others (assuming ASCII bytes of 8 bits or more).  */
      int signbit = *where & (1 << (LG_256 - 2));
      uintmax_t topbits = (((uintmax_t) - signbit)
			   << (CHAR_BIT * sizeof (uintmax_t)
			       - LG_256 - (LG_256 - 2)));
      value = (*where++ & ((1 << (LG_256 - 2)) - 1)) - signbit;
      for (;;)
	{
	  value = (value << LG_256) + (unsigned char) *where++;
	  if (where == lim)
	    break;
	  if (((value << LG_256 >> LG_256) | topbits) != value)
	    {
	      if (type && !silent)
		ERROR ((0, 0,
			_("Archive base-256 value is out of %s range"),
			type));
	      return -1;
	    }
	}
      negative = signbit != 0;
      if (negative)
	value = -value;
    }

  if (where != lim && *where && !isspace ((unsigned char) *where))
    {
      if (type)
	{
	  char buf[1000]; /* Big enough to represent any header.  */
	  static struct quoting_options *o;

	  if (!o)
	    {
	      o = clone_quoting_options (0);
	      set_quoting_style (o, locale_quoting_style);
	    }

	  while (where0 != lim && ! lim[-1])
	    lim--;
	  quotearg_buffer (buf, sizeof buf, where0, lim - where0, o);
	  if (!silent)
	    ERROR ((0, 0,
		    /* TRANSLATORS: Second %s is a type name (gid_t,uid_t,etc.) */
		    _("Archive contains %.*s where numeric %s value expected"),
		    (int) sizeof buf, buf, type));
	}

      return -1;
    }

  if (value <= (negative ? minus_minval : maxval))
    return represent_uintmax (negative ? -value : value);

  if (type && !silent)
    {
      char minval_buf[UINTMAX_STRSIZE_BOUND + 1];
      char maxval_buf[UINTMAX_STRSIZE_BOUND];
      char value_buf[UINTMAX_STRSIZE_BOUND + 1];
      char *minval_string = STRINGIFY_BIGINT (minus_minval, minval_buf + 1);
      char *value_string = STRINGIFY_BIGINT (value, value_buf + 1);
      if (negative)
	*--value_string = '-';
      if (minus_minval)
	*--minval_string = '-';
      /* TRANSLATORS: Second %s is type name (gid_t,uid_t,etc.) */
      ERROR ((0, 0, _("Archive value %s is out of %s range %s..%s"),
	      value_string, type,
	      minval_string, STRINGIFY_BIGINT (maxval, maxval_buf)));
    }

  return -1;
}

Project: tar

base64_init (void)
{
  int i;
  memset (base64_map, 64, sizeof base64_map);
  for (i = 0; i < 64; i++)
    base64_map[(int) base_64_digits[i]] = i;
}

Project: tar

test_archive_label (void)
{
  base64_init ();
  name_gather ();

  open_archive (ACCESS_READ);
  if (read_header (&current_header, &current_stat_info, read_header_auto)
      == HEADER_SUCCESS)
    {
      decode_header (current_header,
		     &current_stat_info, &current_format, 0);
      if (current_header->header.typeflag == GNUTYPE_VOLHDR)
	ASSIGN_STRING_N (&volume_label, current_header->header.name);

      if (volume_label)
	{
	  if (verbose_option)
	    print_volume_label ();
	  if (!name_match (volume_label) && multi_volume_option)
	    {
	      char *s = drop_volume_label_suffix (volume_label);
	      name_match (s);
	      free (s);
	    }
	}
    }
  close_archive ();
  label_notfound ();
}

Project: tar

transform_member_name (char **pinput, int type)
{
  return transform_name_fp (pinput, type, decode_xform, &type);
}

Project: tar

decode_header (union block *header, struct tar_stat_info *stat_info,
	       enum archive_format *format_pointer, int do_user_group)
{
  enum archive_format format;
  bool hbits;
  mode_t mode = MODE_FROM_HEADER (header->header.mode, &hbits);

  if (strcmp (header->header.magic, TMAGIC) == 0)
    {
      if (header->star_header.prefix[130] == 0
	  && ISOCTAL (header->star_header.atime[0])
	  && header->star_header.atime[11] == ' '
	  && ISOCTAL (header->star_header.ctime[0])
	  && header->star_header.ctime[11] == ' ')
	format = STAR_FORMAT;
      else if (stat_info->xhdr.size)
	format = POSIX_FORMAT;
      else
	format = USTAR_FORMAT;
    }
  else if (strcmp (header->buffer + offsetof (struct posix_header, magic),
		   OLDGNU_MAGIC)
	   == 0)
    format = hbits ? OLDGNU_FORMAT : GNU_FORMAT;
  else
    format = V7_FORMAT;
  *format_pointer = format;

  stat_info->stat.st_mode = mode;
  stat_info->mtime.tv_sec = TIME_FROM_HEADER (header->header.mtime);
  stat_info->mtime.tv_nsec = 0;
  assign_string_n (&stat_info->uname,
		   header->header.uname[0] ? header->header.uname : NULL,
		   sizeof (header->header.uname));
  assign_string_n (&stat_info->gname,
		   header->header.gname[0] ? header->header.gname : NULL,
		   sizeof (header->header.gname));

  xheader_xattr_init (stat_info);

  if (format == OLDGNU_FORMAT && incremental_option)
    {
      stat_info->atime.tv_sec = TIME_FROM_HEADER (header->oldgnu_header.atime);
      stat_info->ctime.tv_sec = TIME_FROM_HEADER (header->oldgnu_header.ctime);
      stat_info->atime.tv_nsec = stat_info->ctime.tv_nsec = 0;
    }
  else if (format == STAR_FORMAT)
    {
      stat_info->atime.tv_sec = TIME_FROM_HEADER (header->star_header.atime);
      stat_info->ctime.tv_sec = TIME_FROM_HEADER (header->star_header.ctime);
      stat_info->atime.tv_nsec = stat_info->ctime.tv_nsec = 0;
    }
  else
    stat_info->atime = stat_info->ctime = start_time;

  if (format == V7_FORMAT)
    {
      stat_info->stat.st_uid = UID_FROM_HEADER (header->header.uid);
      stat_info->stat.st_gid = GID_FROM_HEADER (header->header.gid);
      stat_info->stat.st_rdev = 0;
    }
  else
    {
      if (do_user_group)
	{
	  /* FIXME: Decide if this should somewhat depend on -p.  */

	  if (numeric_owner_option
	      || !*header->header.uname
	      || !uname_to_uid (header->header.uname, &stat_info->stat.st_uid))
	    stat_info->stat.st_uid = UID_FROM_HEADER (header->header.uid);

	  if (numeric_owner_option
	      || !*header->header.gname
	      || !gname_to_gid (header->header.gname, &stat_info->stat.st_gid))
	    stat_info->stat.st_gid = GID_FROM_HEADER (header->header.gid);
	}

      switch (header->header.typeflag)
	{
	case BLKTYPE:
	case CHRTYPE:
	  stat_info->stat.st_rdev =
	    makedev (MAJOR_FROM_HEADER (header->header.devmajor),
		     MINOR_FROM_HEADER (header->header.devminor));
	  break;

	default:
	  stat_info->stat.st_rdev = 0;
	}
    }

  xheader_decode (stat_info);

  if (sparse_member_p (stat_info))
    {
      sparse_fixup_header (stat_info);
      stat_info->is_sparse = true;
    }
  else
    {
      stat_info->is_sparse = false;
      if (((current_format == GNU_FORMAT
	    || current_format == OLDGNU_FORMAT)
	   && current_header->header.typeflag == GNUTYPE_DUMPDIR)
          || stat_info->dumpdir)
	stat_info->is_dumpdir = true;
    }
}

Project: tar

skip_file (off_t size)
{
  union block *x;

  /* FIXME: Make sure mv_begin_read is always called before it */

  if (seekable_archive)
    {
      off_t nblk = seek_archive (size);
      if (nblk >= 0)
	size -= nblk * BLOCKSIZE;
      else
	seekable_archive = false;
    }

  mv_size_left (size);

  while (size > 0)
    {
      x = find_next_block ();
      if (! x)
	FATAL_ERROR ((0, 0, _("Unexpected EOF in archive")));

      set_next_block_after (x);
      size -= BLOCKSIZE;
      mv_size_left (size);
    }
}

Project: tar

list_archive (void)
{
  off_t block_ordinal = current_block_ordinal ();

  /* Print the header block.  */
  if (verbose_option)
    print_header (&current_stat_info, current_header, block_ordinal);

  if (incremental_option)
    {
      if (verbose_option > 2)
	{
	  if (is_dumpdir (&current_stat_info))
	    list_dumpdir (current_stat_info.dumpdir,
			  dumpdir_size (current_stat_info.dumpdir));
	}
    }

  skip_member ();
}

Project: tar

print_for_mkdir (char *dirname, int length, mode_t mode)
{
  char modes[11];

  if (verbose_option > 1)
    {
      /* File type and modes.  */

      modes[0] = 'd';
      pax_decode_mode (mode, modes + 1);

      if (block_number_option)
	{
	  char buf[UINTMAX_STRSIZE_BOUND];
	  fprintf (stdlis, _("block %s: "),
		   STRINGIFY_BIGINT (current_block_ordinal (), buf));
	}

      fprintf (stdlis, "%s %*s %s\n", modes, ugswidth + 1 + datewidth,
	       _("Creating directory:"), quotearg (dirname));
    }
}

Project: tar

time_from_header (const char *p, size_t s)
{
  return from_header (p, s, "time_t",
		      TYPE_MINIMUM (time_t), TYPE_MAXIMUM (time_t),
		      false, false);
}

Project: tar

transform_stat_info (int typeflag, struct tar_stat_info *stat_info)
{
  if (typeflag == GNUTYPE_VOLHDR)
    /* Name transformations don't apply to volume headers. */
    return;

  transform_member_name (&stat_info->file_name, XFORM_REGFILE);
  switch (typeflag)
    {
    case SYMTYPE:
      transform_member_name (&stat_info->link_name, XFORM_SYMLINK);
      break;

    case LNKTYPE:
      transform_member_name (&stat_info->link_name, XFORM_LINK);
    }

  if (one_top_level_option)
    enforce_one_top_level (&current_stat_info.file_name);
}

Project: tar

tar_checksum (union block *header, bool silent)
{
  size_t i;
  int unsigned_sum = 0;		/* the POSIX one :-) */
  int signed_sum = 0;		/* the Sun one :-( */
  int recorded_sum;
  int parsed_sum;
  char *p;

  p = header->buffer;
  for (i = sizeof *header; i-- != 0;)
    {
      unsigned_sum += (unsigned char) *p;
      signed_sum += (signed char) (*p++);
    }

  if (unsigned_sum == 0)
    return HEADER_ZERO_BLOCK;

  /* Adjust checksum to count the "chksum" field as blanks.  */

  for (i = sizeof header->header.chksum; i-- != 0;)
    {
      unsigned_sum -= (unsigned char) header->header.chksum[i];
      signed_sum -= (signed char) (header->header.chksum[i]);
    }
  unsigned_sum += ' ' * sizeof header->header.chksum;
  signed_sum += ' ' * sizeof header->header.chksum;

  parsed_sum = from_header (header->header.chksum,
			    sizeof header->header.chksum, 0,
			    0, INT_MAX, true, silent);
  if (parsed_sum < 0)
    return HEADER_FAILURE;

  recorded_sum = parsed_sum;

  if (unsigned_sum != recorded_sum && signed_sum != recorded_sum)
    return HEADER_FAILURE;

  return HEADER_SUCCESS;
}

Project: tar

off_from_header (const char *p, size_t s)
{
  /* Negative offsets are not allowed in tar files, so invoke
     from_header with minimum value 0, not TYPE_MINIMUM (off_t).  */
  return from_header (p, s, "off_t",
		      0, TYPE_MAXIMUM (off_t),
		      false, false);
}

Project: tar

decode_xform (char *file_name, void *data)
{
  int type = *(int*)data;

  switch (type)
    {
    case XFORM_SYMLINK:
      /* FIXME: It is not quite clear how and to which extent are the symbolic
	 links subject to filename transformation.  In the absence of another
	 solution, symbolic links are exempt from component stripping and
	 name suffix normalization, but subject to filename transformation
	 proper. */
      return file_name;

    case XFORM_LINK:
      file_name = safer_name_suffix (file_name, true, absolute_names_option);
      break;

    case XFORM_REGFILE:
      file_name = safer_name_suffix (file_name, false, absolute_names_option);
      break;
    }

  if (strip_name_components)
    {
      size_t prefix_len = stripped_prefix_len (file_name,
					       strip_name_components);
      if (prefix_len == (size_t) -1)
	prefix_len = strlen (file_name);
      file_name += prefix_len;
    }
  return file_name;
}

Project: tar

uid_from_header (const char *p, size_t s)
{
  return from_header (p, s, "uid_t",
		      TYPE_MINIMUM (uid_t), TYPE_MAXIMUM (uid_t),
		      false, false);
}

Project: tar

print_volume_label (void)
{
  struct tar_stat_info vstat;
  union block vblk;
  enum archive_format dummy;

  memset (&vblk, 0, sizeof (vblk));
  vblk.header.typeflag = GNUTYPE_VOLHDR;
  if (recent_global_header)
    memcpy (vblk.header.mtime, recent_global_header->header.mtime,
	    sizeof vblk.header.mtime);
  tar_stat_init (&vstat);
  assign_string (&vstat.file_name, ".");
  decode_header (&vblk, &vstat, &dummy, 0);
  assign_string (&vstat.file_name, volume_label);
  simple_print_header (&vstat, &vblk, 0);
  tar_stat_destroy (&vstat);
}

Project: tar

enforce_one_top_level (char **pfile_name)
{
  char *file_name = *pfile_name;
  char *p;

  for (p = file_name; *p && (ISSLASH (*p) || *p == '.'); p++)
    ;

  if (*p)
    {
      int pos = strlen (one_top_level_dir);
      if (strncmp (p, one_top_level_dir, pos) == 0)
	{
	  if (ISSLASH (p[pos]) || p[pos] == 0)
	    return;
	}

      *pfile_name = make_file_name (one_top_level_dir, file_name);
      normalize_filename_x (*pfile_name);
    }
  else
    *pfile_name = xstrdup (one_top_level_dir);
  free (file_name);
}

Project: tar

gid_from_header (const char *p, size_t s)
{
  return from_header (p, s, "gid_t",
		      TYPE_MINIMUM (gid_t), TYPE_MAXIMUM (gid_t),
		      false, false);
}

Project: tar

read_header (union block **return_block, struct tar_stat_info *info,
	     enum read_header_mode mode)
{
  union block *header;
  char *bp;
  union block *data_block;
  size_t size, written;
  union block *next_long_name = NULL;
  union block *next_long_link = NULL;
  size_t next_long_name_blocks = 0;
  size_t next_long_link_blocks = 0;
  enum read_header status = HEADER_SUCCESS;
  
  while (1)
    {
      header = find_next_block ();
      *return_block = header;
      if (!header)
	{
	  status = HEADER_END_OF_FILE;
	  break;
	}

      if ((status = tar_checksum (header, false)) != HEADER_SUCCESS)
	break;

      /* Good block.  Decode file size and return.  */

      if (header->header.typeflag == LNKTYPE)
	info->stat.st_size = 0;	/* links 0 size on tape */
      else
	{
	  info->stat.st_size = OFF_FROM_HEADER (header->header.size);
	  if (info->stat.st_size < 0)
	    {
	      status = HEADER_FAILURE;
	      break;
	    }
	}

      if (header->header.typeflag == GNUTYPE_LONGNAME
	  || header->header.typeflag == GNUTYPE_LONGLINK
	  || header->header.typeflag == XHDTYPE
	  || header->header.typeflag == XGLTYPE
	  || header->header.typeflag == SOLARIS_XHDTYPE)
	{
	  if (mode == read_header_x_raw)
	    {
	      status = HEADER_SUCCESS_EXTENDED;
	      break;
	    }
	  else if (header->header.typeflag == GNUTYPE_LONGNAME
		   || header->header.typeflag == GNUTYPE_LONGLINK)
	    {
	      union block *header_copy;
	      size_t name_size = info->stat.st_size;
	      size_t n = name_size % BLOCKSIZE;
	      size = name_size + BLOCKSIZE;
	      if (n)
		size += BLOCKSIZE - n;

	      if (name_size != info->stat.st_size || size < name_size)
		xalloc_die ();

	      header_copy = xmalloc (size + 1);

	      if (header->header.typeflag == GNUTYPE_LONGNAME)
		{
		  free (next_long_name);
		  next_long_name = header_copy;
		  next_long_name_blocks = size / BLOCKSIZE;
		}
	      else
		{
		  free (next_long_link);
		  next_long_link = header_copy;
		  next_long_link_blocks = size / BLOCKSIZE;
		}

	      set_next_block_after (header);
	      *header_copy = *header;
	      bp = header_copy->buffer + BLOCKSIZE;

	      for (size -= BLOCKSIZE; size > 0; size -= written)
		{
		  data_block = find_next_block ();
		  if (! data_block)
		    {
		      ERROR ((0, 0, _("Unexpected EOF in archive")));
		      break;
		    }
		  written = available_space_after (data_block);
		  if (written > size)
		    written = size;

		  memcpy (bp, data_block->buffer, written);
		  bp += written;
		  set_next_block_after ((union block *)
					(data_block->buffer + written - 1));
		}

	      *bp = '\0';
	    }
	  else if (header->header.typeflag == XHDTYPE
		   || header->header.typeflag == SOLARIS_XHDTYPE)
	    xheader_read (&info->xhdr, header,
			  OFF_FROM_HEADER (header->header.size));
	  else if (header->header.typeflag == XGLTYPE)
	    {
	      struct xheader xhdr;

	      if (!recent_global_header)
		recent_global_header = xmalloc (sizeof *recent_global_header);
	      memcpy (recent_global_header, header,
		      sizeof *recent_global_header);
	      memset (&xhdr, 0, sizeof xhdr);
	      xheader_read (&xhdr, header,
			    OFF_FROM_HEADER (header->header.size));
	      xheader_decode_global (&xhdr);
	      xheader_destroy (&xhdr);
	      if (mode == read_header_x_global)
		{
		  status = HEADER_SUCCESS_EXTENDED;
		  break;
		}
	    }

	  /* Loop!  */

	}
      else
	{
	  char const *name;
	  struct posix_header const *h = &header->header;
	  char namebuf[sizeof h->prefix + 1 + NAME_FIELD_SIZE + 1];

	  free (recent_long_name);

	  if (next_long_name)
	    {
	      name = next_long_name->buffer + BLOCKSIZE;
	      recent_long_name = next_long_name;
	      recent_long_name_blocks = next_long_name_blocks;
	      next_long_name = NULL;
	    }
	  else
	    {
	      /* Accept file names as specified by POSIX.1-1996
                 section 10.1.1.  */
	      char *np = namebuf;

	      if (h->prefix[0] && strcmp (h->magic, TMAGIC) == 0)
		{
		  memcpy (np, h->prefix, sizeof h->prefix);
		  np[sizeof h->prefix] = '\0';
		  np += strlen (np);
		  *np++ = '/';
		}
	      memcpy (np, h->name, sizeof h->name);
	      np[sizeof h->name] = '\0';
	      name = namebuf;
	      recent_long_name = 0;
	      recent_long_name_blocks = 0;
	    }
	  assign_string (&info->orig_file_name, name);
	  assign_string (&info->file_name, name);
	  info->had_trailing_slash = strip_trailing_slashes (info->file_name);

	  free (recent_long_link);

	  if (next_long_link)
	    {
	      name = next_long_link->buffer + BLOCKSIZE;
	      recent_long_link = next_long_link;
	      recent_long_link_blocks = next_long_link_blocks;
	      next_long_link = NULL;
	    }
	  else
	    {
	      memcpy (namebuf, h->linkname, sizeof h->linkname);
	      namebuf[sizeof h->linkname] = '\0';
	      name = namebuf;
	      recent_long_link = 0;
	      recent_long_link_blocks = 0;
	    }
	  assign_string (&info->link_name, name);

	  break;
	}
    }
  free (next_long_name);
  free (next_long_link);
  return status;
}

Project: tar

print_header (struct tar_stat_info *st, union block *blk,
	      off_t block_ordinal)
{
  if (current_format == POSIX_FORMAT && !volume_label_printed && volume_label)
    {
      print_volume_label ();
      volume_label_printed = true;
    }

  simple_print_header (st, blk, block_ordinal);
}