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libarchive-3-8-11:1.1.1.9
libarchive-3-8-10:1.1.1.9
pkgsrc-2026Q3:1.10.0.2
pkgsrc-2026Q3-base:1.10
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libarchive-3-8-8:1.1.1.8
pkgsrc-2026Q2:1.9.0.10
pkgsrc-2026Q2-base:1.9
libarchive-3-8-7:1.1.1.7
libarchive-3-8-6:1.1.1.7
pkgsrc-2026Q1:1.9.0.8
pkgsrc-2026Q1-base:1.9
libarchive-3-8-5:1.1.1.7
libarchive-3-8-4:1.1.1.7
pkgsrc-2025Q4:1.9.0.6
pkgsrc-2025Q4-base:1.9
libarchive-3-8-3:1.1.1.7
libarchive-3-8-2:1.1.1.7
pkgsrc-2025Q3:1.9.0.4
pkgsrc-2025Q3-base:1.9
libarchive-3-8-1:1.1.1.7
pkgsrc-2025Q2:1.9.0.2
pkgsrc-2025Q2-base:1.9
libarchive-3-8-0:1.1.1.7
libarchive-3-7-9:1.1.1.6
pkgsrc-2025Q1:1.8.0.10
pkgsrc-2025Q1-base:1.8
pkgsrc-2024Q4:1.8.0.8
pkgsrc-2024Q4-base:1.8
libarchive-3-7-7:1.1.1.6
pkgsrc-2024Q3:1.8.0.6
pkgsrc-2024Q3-base:1.8
libarchive-3-7-5:1.1.1.6
pkgsrc-2024Q2:1.8.0.4
pkgsrc-2024Q2-base:1.8
libarchive-3-7-4:1.1.1.6
libarchive-3-7-3:1.1.1.6
pkgsrc-2024Q1:1.8.0.2
pkgsrc-2024Q1-base:1.8
libarchive-3-7-2:1.1.1.6
pkgsrc-2023Q4:1.7.0.30
pkgsrc-2023Q4-base:1.7
pkgsrc-2023Q3:1.7.0.28
pkgsrc-2023Q3-base:1.7
pkgsrc-2023Q2:1.7.0.26
pkgsrc-2023Q2-base:1.7
pkgsrc-2023Q1:1.7.0.24
pkgsrc-2023Q1-base:1.7
pkgsrc-2022Q4:1.7.0.22
pkgsrc-2022Q4-base:1.7
pkgsrc-2022Q3:1.7.0.20
pkgsrc-2022Q3-base:1.7
pkgsrc-2022Q2:1.7.0.18
pkgsrc-2022Q2-base:1.7
pkgsrc-2022Q1:1.7.0.16
pkgsrc-2022Q1-base:1.7
pkgsrc-2021Q4:1.7.0.14
pkgsrc-2021Q4-base:1.7
pkgsrc-2021Q3:1.7.0.12
pkgsrc-2021Q3-base:1.7
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pkgsrc-2021Q2-base:1.7
pkgsrc-2021Q1:1.7.0.8
pkgsrc-2021Q1-base:1.7
pkgsrc-2020Q4:1.7.0.6
pkgsrc-2020Q4-base:1.7
pkgsrc-2020Q3:1.7.0.4
pkgsrc-2020Q3-base:1.7
pkgsrc-2020Q2:1.7.0.2
pkgsrc-2020Q2-base:1.7
pkgsrc-2020Q1:1.6.0.4
pkgsrc-2020Q1-base:1.6
pkgsrc-2019Q4:1.6.0.6
pkgsrc-2019Q4-base:1.6
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pkgsrc-2019Q3-base:1.6
libarchive-3-4-0:1.1.1.5
libarchive-3-3-3:1.1.1.4
pkgsrc-2019Q2:1.5.0.18
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pkgsrc-2019Q1-base:1.5
pkgsrc-2018Q4:1.5.0.14
pkgsrc-2018Q4-base:1.5
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pkgsrc-2018Q1-base:1.5
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pkgsrc-2017Q3:1.5.0.4
pkgsrc-2017Q3-base:1.5
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libarchive-3-3-1:1.1.1.3
pkgsrc-2016Q4:1.3.0.6
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pkgsrc-2016Q3-base:1.3
pkgsrc-2016Q2:1.3.0.2
pkgsrc-2016Q2-base:1.3
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pkgsrc-2016Q1:1.2.0.10
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pkgsrc-2015Q3:1.2.0.6
pkgsrc-2015Q3-base:1.2
pkgsrc-2015Q2:1.2.0.4
pkgsrc-2015Q2-base:1.2
pkgsrc-2015Q1:1.2.0.2
pkgsrc-2015Q1-base:1.2
pkgsrc-2014Q4:1.1.1.1.0.40
pkgsrc-2014Q4-base:1.1.1.1
pkgsrc-2014Q3:1.1.1.1.0.38
pkgsrc-2014Q3-base:1.1.1.1
pkgsrc-2014Q2:1.1.1.1.0.36
pkgsrc-2014Q2-base:1.1.1.1
pkgsrc-2014Q1:1.1.1.1.0.34
pkgsrc-2014Q1-base:1.1.1.1
pkgsrc-2013Q4:1.1.1.1.0.32
pkgsrc-2013Q4-base:1.1.1.1
pkgsrc-2013Q3:1.1.1.1.0.30
pkgsrc-2013Q3-base:1.1.1.1
pkgsrc-2013Q2:1.1.1.1.0.28
pkgsrc-2013Q2-base:1.1.1.1
pkgsrc-2013Q1:1.1.1.1.0.26
pkgsrc-2013Q1-base:1.1.1.1
pkgsrc-2012Q4:1.1.1.1.0.24
pkgsrc-2012Q4-base:1.1.1.1
pkgsrc-2012Q3:1.1.1.1.0.22
pkgsrc-2012Q3-base:1.1.1.1
pkgsrc-2012Q2:1.1.1.1.0.20
pkgsrc-2012Q2-base:1.1.1.1
pkgsrc-2012Q1:1.1.1.1.0.18
pkgsrc-2012Q1-base:1.1.1.1
pkgsrc-2011Q4:1.1.1.1.0.16
pkgsrc-2011Q4-base:1.1.1.1
pkgsrc-2011Q3:1.1.1.1.0.14
pkgsrc-2011Q3-base:1.1.1.1
pkgsrc-2011Q2:1.1.1.1.0.12
pkgsrc-2011Q2-base:1.1.1.1
pkgsrc-2011Q1:1.1.1.1.0.10
pkgsrc-2011Q1-base:1.1.1.1
pkgsrc-2010Q4:1.1.1.1.0.8
pkgsrc-2010Q4-base:1.1.1.1
pkgsrc-2010Q3:1.1.1.1.0.6
pkgsrc-2010Q3-base:1.1.1.1
libarchive-2-8-4:1.1.1.1
pkgsrc-2010Q2:1.1.1.1.0.4
pkgsrc-2010Q2-base:1.1.1.1
pkgsrc-2010Q1:1.1.1.1.0.2
pkgsrc-2010Q1-base:1.1.1.1
libarchive-2-8-3:1.1.1.1
libarchive-2-8-2:1.1.1.1
libarchive-2-8-0:1.1.1.1
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desc
@@
1.11
log
@libarchive: updated to 3.8.10
3.8.10
New features:
7z: add Delta, RISCV, ARMTHUMB and IA64 filters for non-lzma archives
libarchive: support digest with nettle 4 and mbedtls 3
tar: add --mode option
Security and Bug Fixes
see ChangeLog
@
text
@LIBARCHIVE-FORMATS(5) manual page
== NAME ==
'''libarchive-formats'''
- archive formats supported by the libarchive library
== DESCRIPTION ==
The
[[ManPageLibarchive3]]
library reads and writes a variety of streaming archive formats.
Generally speaking, all of these archive formats consist of a series of
"entries".
Each entry stores a single file system object, such as a file, directory,
or symbolic link.
The following provides a brief description of each format supported
by libarchive, with some information about recognized extensions or
limitations of the current library support.
Note that just because a format is supported by libarchive does not
imply that a program that uses libarchive will support that format.
Applications that use libarchive specify which formats they wish
to support, though many programs do use libarchive convenience
functions to enable all supported formats.
=== Tar Formats===
The
[[ManPageLibarchive3]]
library can read most tar archives.
It can write POSIX-standard
"ustar"
and
"pax interchange"
formats as well as v7 tar format and a subset of the legacy GNU tar format.
All tar formats store each entry in one or more 512-byte records.
The first record is used for file metadata, including filename,
timestamp, and mode information, and the file data is stored in
subsequent records.
Later variants have extended this by either appropriating undefined
areas of the header record, extending the header to multiple records,
or by storing special entries that modify the interpretation of
subsequent entries.
- '''gnutar'''
-
The
[[ManPageLibarchive3]]
library can read most GNU-format tar archives.
It currently supports the most popular GNU extensions, including
modern long filename and linkname support, as well as atime and ctime data.
The libarchive library does not support multi-volume
archives, nor the old GNU long filename format.
It can read GNU sparse file entries, including the new POSIX-based
formats.
The
[[ManPageLibarchive3]]
library can write GNU tar format, including long filename
and linkname support, as well as atime and ctime data.
- '''pax'''
-
The
[[ManPageLibarchive3]]
library can read and write POSIX-compliant pax interchange format
archives.
Pax interchange format archives are an extension of the older ustar
format that adds a separate entry with additional attributes stored
as key/value pairs immediately before each regular entry.
The presence of these additional entries is the only difference between
pax interchange format and the older ustar format.
The extended attributes are of unlimited length and are stored
as UTF-8 Unicode strings.
Keywords defined in the standard are in all lowercase; vendors are allowed
to define custom keys by preceding them with the vendor name in all uppercase.
When writing pax archives, libarchive uses many of the SCHILY keys
defined by Joerg Schilling's
"star"
archiver and a few LIBARCHIVE keys.
The libarchive library can read most of the SCHILY keys
and most of the GNU keys introduced by GNU tar.
It silently ignores any keywords that it does not understand.
The pax interchange format converts filenames to Unicode
and stores them using the UTF-8 encoding.
Prior to libarchive 3.0, libarchive erroneously assumed
that the system wide-character routines natively supported
Unicode.
This caused it to mis-handle non-ASCII filenames on systems
that did not satisfy this assumption.
- '''restricted''' pax
-
The libarchive library can also write pax archives in which it
attempts to suppress the extended attributes entry whenever
possible.
The result will be identical to a ustar archive unless the
extended attributes entry is required to store a long file
name, long linkname, extended ACL, file flags, or if any of the standard
ustar data (user name, group name, UID, GID, etc) cannot be fully
represented in the ustar header.
In all cases, the result can be dearchived by any program that
can read POSIX-compliant pax interchange format archives.
Programs that correctly read ustar format (see below) will also be
able to read this format; any extended attributes will be extracted as
separate files stored in
''PaxHeader''
directories.
- '''ustar'''
-
The libarchive library can both read and write this format.
This format has the following limitations:
-
Device major and minor numbers are limited to 21 bits.
Nodes with larger numbers will not be added to the archive.
-
Path names in the archive are limited to 255 bytes.
(Shorter if there is no / character in exactly the right place.)
-
Symbolic links and hard links are stored in the archive with
the name of the referenced file.
This name is limited to 100 bytes.
-
Extended attributes, file flags, and other extended
security information cannot be stored.
-
Archive entries are limited to 8 gigabytes in size.
Note that the pax interchange format has none of these restrictions.
The ustar format is old and widely supported.
It is recommended when compatibility is the primary concern.
- '''v7'''
-
The libarchive library can read and write the legacy v7 tar format.
This format has the following limitations:
-
Only regular files, directories, and symbolic links can be archived.
Block and character device nodes, FIFOs, and sockets cannot be archived.
-
Path names in the archive are limited to 100 bytes.
-
Symbolic links and hard links are stored in the archive with
the name of the referenced file.
This name is limited to 100 bytes.
-
User and group information are stored as numeric IDs; there
is no provision for storing user or group names.
-
Extended attributes, file flags, and other extended
security information cannot be stored.
-
Archive entries are limited to 8 gigabytes in size.
Generally, users should prefer the ustar format for portability
as the v7 tar format is both less useful and less portable.
The libarchive library also reads a variety of commonly-used extensions to
the basic tar format.
These extensions are recognized automatically whenever they appear.
- Numeric extensions.
-
The POSIX standards require fixed-length numeric fields to be written with
some character position reserved for terminators.
Libarchive allows these fields to be written without terminator characters.
This extends the allowable range; in particular, ustar archives with this
extension can support entries up to 64 gigabytes in size.
Libarchive also recognizes base-256 values in most numeric fields.
This essentially removes all limitations on file size, modification time,
and device numbers.
- Solaris extensions
-
Libarchive recognizes ACL and extended attribute records written
by Solaris tar.
The first tar program appeared in Seventh Edition Unix in 1979.
The first official standard for the tar file format was the
"ustar"
(Unix Standard Tar) format defined by POSIX in 1988.
POSIX.1-2001 extended the ustar format to create the
"pax interchange"
format.
=== Cpio Formats===
The libarchive library can read and write a number of common cpio
variants. A cpio archive stores each entry as a fixed-size header
followed by a variable-length filename and variable-length data.
Unlike the tar format, the cpio format does only minimal padding of
the header or file data. There are several cpio variants, which
differ primarily in how they store the initial header: some store the
values as octal or hexadecimal numbers in ASCII, others as binary
values of varying byte order and length.
- '''binary'''
-
The libarchive library transparently reads both big-endian and
little-endian variants of the two binary cpio formats; the
original one from PWB/UNIX, and the later, more widely used, variant.
This format used 32-bit binary values for file size and mtime, and
16-bit binary values for the other fields. The formats support only
the file types present in UNIX at the time of their creation. File
sizes are limited to 24 bits in the PWB format, because of the limits
of the file system, and to 31 bits in the newer binary format, where
signed 32 bit longs were used.
- '''odc'''
-
This is the POSIX standardized format, which is officially known as the
"cpio interchange format"
or the
"octet-oriented cpio archive format"
and sometimes unofficially referred to as the
"old character format".
This format stores the header contents as octal values in ASCII.
It is standard, portable, and immune from byte-order confusion.
File sizes and mtime are limited to 33 bits (8GB file size),
other fields are limited to 18 bits.
- '''SVR4/newc'''
-
The libarchive library can read both CRC and non-CRC variants of
this format.
The SVR4 format uses eight-digit hexadecimal values for
all header fields.
This limits file size to 4GB, and also limits the mtime and
other fields to 32 bits.
The SVR4 format can optionally include a CRC of the file
contents, although libarchive does not currently verify this CRC.
Cpio first appeared in PWB/UNIX 1.0, which was released within
AT&T in 1977.
PWB/UNIX 1.0 formed the basis of System III Unix, released outside
of AT&T in 1981.
This makes cpio older than tar, although cpio was not included
in Version 7 AT&T Unix.
As a result, the tar command became much better known in universities
and research groups that used Version 7.
The combination of the
'''find'''
and
'''cpio'''
utilities provided very precise control over file selection.
Unfortunately, the format has many limitations that make it unsuitable
for widespread use.
Only the POSIX format permits files over 4GB, and its 18-bit
limit for most other fields makes it unsuitable for modern systems.
In addition, cpio formats only store numeric UID/GID values (not
usernames and group names), which can make it very difficult to correctly
transfer archives across systems with dissimilar user numbering.
=== Shar Formats===
A
"shell archive"
is a shell script that, when executed on a POSIX-compliant
system, will recreate a collection of file system objects.
The libarchive library can write two different kinds of shar archives:
- '''shar'''
-
The traditional shar format uses a limited set of POSIX
commands, including
[[echo(1)|http://www.freebsd.org/cgi/man.cgi?query=echo&sektion=1]],
[[mkdir(1)|http://www.freebsd.org/cgi/man.cgi?query=mkdir&sektion=1]],
and
[[sed(1)|http://www.freebsd.org/cgi/man.cgi?query=sed&sektion=1]].
It is suitable for portably archiving small collections of plain text files.
However, it is not generally well-suited for large archives
(many implementations of
[[sh(1)|http://www.freebsd.org/cgi/man.cgi?query=sh&sektion=1]]
have limits on the size of a script) nor should it be used with non-text files.
- '''shardump'''
-
This format is similar to shar but encodes files using
[[uuencode(1)|http://www.freebsd.org/cgi/man.cgi?query=uuencode&sektion=1]]
so that the result will be a plain text file regardless of the file contents.
It also includes additional shell commands that attempt to reproduce as
many file attributes as possible, including owner, mode, and flags.
The additional commands used to restore file attributes make
shardump archives less portable than plain shar archives.
=== ISO9660 format===
Libarchive can read and extract from files containing ISO9660-compliant
CDROM images.
In many cases, this can remove the need to burn a physical CDROM
just in order to read the files contained in an ISO9660 image.
It also avoids security and complexity issues that come with
virtual mounts and loopback devices.
Libarchive supports the most common Rockridge extensions and has partial
support for Joliet extensions.
If both extensions are present, the Joliet extensions will be
used and the Rockridge extensions will be ignored.
In particular, this can create problems with hardlinks and symlinks,
which are supported by Rockridge but not by Joliet.
Libarchive reads ISO9660 images using a streaming strategy.
This allows it to read compressed images directly
(decompressing on the fly) and allows it to read images
directly from network sockets, pipes, and other non-seekable
data sources.
This strategy works well for optimized ISO9660 images created
by many popular programs.
Such programs collect all directory information at the beginning
of the ISO9660 image so it can be read from a physical disk
with a minimum of seeking.
However, not all ISO9660 images can be read in this fashion.
Libarchive can also write ISO9660 images.
Such images are fully optimized with the directory information
preceding all file data.
This is done by storing all file data to a temporary file
while collecting directory information in memory.
When the image is finished, libarchive writes out the
directory structure followed by the file data.
The location used for the temporary file can be changed
by the usual environment variables.
=== Zip format===
Libarchive can read and write zip format archives that have
uncompressed entries and entries compressed with the
"deflate"
,
"LZMA"
,
"XZ"
,
"BZIP2"
and
"ZSTD"
algorithms.
Libarchive can also read, but not write, zip format archives that
have entries compressed with the
"PPMd"
algorithm.
Other zip compression algorithms are not supported.
The extensions supported by libarchive are Zip64, Libarchive's
extensions to better support streaming, PKZIP's traditional
ZIP encryption, Info-ZIP's Unix extra fields, extra time, and
Unicode path, as well as WinZIP's AES encryption.
It can extract jar archives, __MACOSX resource forks extension
for OS X, and self-extracting zip archives.
Libarchive can use either of two different strategies for
reading Zip archives:
a streaming strategy which is fast and can handle extremely
large archives, and a seeking strategy which can correctly
process self-extracting Zip archives and archives with
deleted members or other in-place modifications.
The streaming reader processes Zip archives as they are read.
It can read archives of arbitrary size from tape or
network sockets, and can decode Zip archives that have
been separately compressed or encoded.
However, self-extracting Zip archives and archives with
certain types of modifications cannot be correctly
handled.
Such archives require that the reader first process the
Central Directory, which is ordinarily located
at the end of a Zip archive and is thus inaccessible
to the streaming reader.
If the program using libarchive has enabled seek support, then
libarchive will use this to process the central directory first.
In particular, the seeking reader must be used to
correctly handle self-extracting archives.
Such archives consist of a program followed by a regular
Zip archive.
The streaming reader cannot parse the initial program
portion, but the seeking reader starts by reading the
Central Directory from the end of the archive.
Similarly, Zip archives that have been modified in-place
can have deleted entries or other garbage data that
can only be accurately detected by first reading the
Central Directory.
=== Archive (library) file format===
The Unix archive format (commonly created by the
[[ar(1)|http://www.freebsd.org/cgi/man.cgi?query=ar&sektion=1]]
archiver) is a general-purpose format which is
used almost exclusively for object files to be
read by the link editor
[[ld(1)|http://www.freebsd.org/cgi/man.cgi?query=ld&sektion=1]].
The ar format has never been standardised.
There are two common variants:
the GNU format derived from SVR4,
and the BSD format, which first appeared in 4.4BSD.
The two differ primarily in their handling of filenames
longer than 15 characters:
the GNU/SVR4 variant writes a filename table at the beginning of the archive;
the BSD format stores each long filename in an extension
area adjacent to the entry.
Libarchive can read both extensions,
including archives that may include both types of long filenames.
Programs using libarchive can write GNU/SVR4 format
if they provide an entry called
''//''
containing a filename table to be written into the archive
before any of the entries.
Any entries whose names are not in the filename table
will be written using BSD-style long filenames.
This can cause problems for programs such as
GNU ld that do not support the BSD-style long filenames.
=== mtree===
Libarchive can read and write files in
[[ManPageMtree5]]
format.
This format is not a true archive format, but rather a textual description
of a file hierarchy in which each line specifies the name of a file and
provides specific metadata about that file.
Libarchive can read all of the keywords supported by both
the NetBSD and FreeBSD versions of
[[mtree(8)|http://www.freebsd.org/cgi/man.cgi?query=mtree&sektion=8]],
although many of the keywords cannot currently be stored in an
'''archive_entry'''
object.
When writing, libarchive supports use of the
[[ManPageArchiveWriteSetOptions3]]
interface to specify which keywords should be included in the
output.
If libarchive was compiled with access to suitable
cryptographic libraries (such as the OpenSSL libraries),
it can compute hash entries such as
'''sha512'''
or
'''md5'''
from file data being written to the mtree writer.
When reading an mtree file, libarchive will locate the corresponding
files on disk using the
'''contents'''
keyword if present or the regular filename.
If it can locate and open the file on disk, it will use that
to fill in any metadata that is missing from the mtree file
and will read the file contents and return those to the program
using libarchive.
If it cannot locate and open the file on disk, libarchive
will return an error for any attempt to read the entry
body.
=== 7-Zip===
Libarchive can read and write 7-Zip format archives.
TODO: Need more information
=== CAB===
Libarchive can read Microsoft Cabinet (
"CAB )"
format archives.
TODO: Need more information.
=== LHA===
TODO: Information about libarchive's LHA support
=== RAR===
Libarchive has limited support for reading RAR format archives.
Currently, libarchive can read RARv3 format archives
which have been either created uncompressed, or compressed using
any of the compression methods supported by the RARv3 format.
Libarchive can also read self-extracting RAR archives.
=== Warc===
Libarchive can read and write
"web archives".
TODO: Need more information
=== XAR===
Libarchive can read and write the XAR format used by many Apple tools.
TODO: Need more information
== SEE ALSO ==
[[ar(1)|http://www.freebsd.org/cgi/man.cgi?query=ar&sektion=1]],
[[ManPageBsdcpio1]],
[[mkisofs(1)|http://www.freebsd.org/cgi/man.cgi?query=mkisofs&sektion=1]],
[[shar(1)|http://www.freebsd.org/cgi/man.cgi?query=shar&sektion=1]],
[[ManPageBsdtar1]],
[[zip(1)|http://www.freebsd.org/cgi/man.cgi?query=zip&sektion=1]],
[[zlib(3)|http://www.freebsd.org/cgi/man.cgi?query=zlib&sektion=3]],
[[ManPageCpio5]],
[[ManPageMtree5]],
[[ManPageTar5]]
@
1.10
log
@libarchive: updated to 3.8.8
Libarchive 3.8.8 is a security, bugfix and minor feature release.
New features:
add support for reading encrypted zipx formats (bzip2, lzma, ppmd, xz, zstd)
Fix overview:
https://github.com/libarchive/libarchive/releases/tag/v3.8.8
@
text
@d343 1
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libarchive will use this to processes the central directory first.
@
1.9
log
@libarchive bsdtar: updated to 3.8.0
Libarchive 3.8.0 is a feature and bugfix release.
New features:
bsdtar: support --mtime and --clamp-mtime
lib: mbedtls 3.x compatibility
7-zip reader: improve self-extracting archive detection
xar: xmllite support for the XAR reader and writer
zip writer: added XZ, LZMA, ZSTD and BZIP2 support
zip writer: added LZMA + RISCV BCJ filter
Notable security fixes:
rar: do not skip past EOF while reading
rar: fix double free with over 4 billion nodes
rar: fix heap-buffer-overflow
warc: prevent signed integer overflow
tar: fix overflow in build_ustar_entry
Notable bugfixes:
bsdtar: don't hardlink negative inode files together
gz: allow setting the original filename for gzip compressed files
lib: improve lseek handling
lib: support @@-prefixed Unix epoch timestamps as date strings
rar: support large headers on 32 bit systems
tar reader: Improve LFS support on 32 bit systems
@
text
@d187 1
a187 1
little-endian variants of the the two binary cpio formats; the
@
1.8
log
@libarchive: updated to 3.7.2
Libarchive 3.7.2 is a security, bugfix and feature release.
Security fixes:
Multiple vulnerabilities have been fixed in the PAX writer (1b4e0d0)
Important bugfixes:
bsdunzip(1) now correctly handles arguments following an -x after the zipfile
New features:
bsdunzip(1) now supports the "--version" flag
7-zip reader now translates Windows permissions into UNIX permissions
uudecode filter in raw mode now supports file name and file mode
zstd filter now supports the "long" write option
Libarchive 3.7.1 is a security, feature and bugfix release.
Security fixes:
SEGV and stack buffer overflow in verbose mode of cpio
Feature updates:
bsdunzip updated to match latest upstream code
Important bugfixes:
miscellaneous functional bugfixes
build fixes on multiple platforms
Libarchive 3.7.0 is a feature and bugfix release.
New features:
bsdunzip: new tool ported from FreeBSD
drop-in replacement for Info-ZIP unzip, not yet ported for Windows
7zip reader: support for Zstandard compression
7zip reader: support for ARM64 filter
zstd filter: support for multi-frame zstd archives
Other notable bugfixes and improvements:
pax: fix year 2038 problem on platforms with 64-bit time_t
Windows: Universal Windows Platform (UWP) fixes and improvements
Windows: bcrypt usage fixes and improvements
Windows: time function usage fixes and improvements
@
text
@d304 12
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a323 2
It can extract jar archives, archives that use Zip64 extensions and
self-extracting zip archives.
@
1.7
log
@libarchive: Update to 3.4.3
Libarchive 3.4.3 is a feature and bugfix release.
New features:
support for pzstd compressed files (#1357)
support for RHT.security.selinux tar extended attribute (#1348)
Important bugfixes:
various zstd fixes and improvements (#1342 #1352 #1359)
child process handling fixes (#1372)
Libarchive 3.4.2 is a feature and security release.
New features:
support for atomic file extraction (bsdtar -x --safe-writes) (#1289)
support for mbed TLS (PolarSSL) (#1301)
Important bugfixes:
security fixes in RAR5 reader (#1280 #1326)
compression buffer fix in XAR writer (#1317)
fix uname and gname longer than 32 characters in PAX writer (#1319)
fix segfault when archiving hard links in ISO9660 and XAR writers (#1325)
fix support for extracting 7z archive entries with Delta filter (#987)
Libarchive 3.4.1 is a feature and security release.
New features:
Unicode filename support for reading lha/lzh archives
New pax write option "xattrhdr"
Important bugfixes:
security fixes in wide string processing (#1276 #1298)
security fixes in RAR5 reader (#1212 #1217 #1296)
security fixes and optimizations to write filter logic (#351)
security fix related to use of readlink(2) (1dae5a5)
sparse file handling fixes (#1218 #1260)
Thanks to all contributors and bug reporters.
Special thanks to Christos Zoulas (@@zoulasc) from NetBSD for the atomic file extraction feature.
@
text
@d7 1
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
d58 1
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[[ManPageibarchive3]]
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a183 13
The libarchive library can read a number of common cpio variants and can write
"odc"
and
"newc"
format archives.
A cpio archive stores each entry as a fixed-size header followed
by a variable-length filename and variable-length data.
Unlike the tar format, the cpio format does only minimal padding
of the header or file data.
There are several cpio variants, which differ primarily in
how they store the initial header: some store the values as
octal or hexadecimal numbers in ASCII, others as binary values of
varying byte order and length.
d186 9
a194 4
The libarchive library transparently reads both big-endian and little-endian
variants of the original binary cpio format.
This format used 32-bit binary values for file size and mtime,
and 16-bit binary values for the other fields.
d196 1
a196 2
The libarchive library can both read and write this
POSIX-standard format, which is officially known as the
d381 1
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[[ManPagerchiveriteetptions3]]
@
1.6
log
@Update for libarchive-3.4.0:
- improvements for Android APK and JAR archives
- better support for non-recursive list and extract
- tar --exclude-vcs support
- fixes for file attributes and flags handling
- zipx support
- rar 5.0 reader
@
text
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
d382 1
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[[ManPageArchiveWriteSetOptions3]]
@
1.5
log
@Merge for libarchive-3.3.2.
@
text
@d7 1
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPagerchiveriteetptions3]]
@
1.4
log
@Merge libarchive-3.3.1.
@
text
@d7 1
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
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[[ManPageLibarchive3]]
d58 1
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[[ManPageLibarchive3]]
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[[ManPageArchiveWriteSetOptions3]]
@
1.3
log
@Update for libarchive 3.2.1.
@
text
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
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[[ManPageibarchive3]]
a165 2
Currently, libarchive only has support for old-style ACLs; the
newer NFSv4 ACLs are recognized but discarded.
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[[ManPagerchiveriteetptions3]]
@
1.2
log
@Changes 3.1.2:
This is a maintenance update to fix issues with the new RAR seeking
feature. This new release also contains fixes for build failures when
building libarchive using Visual Studio 2012 and MinGW.
@
text
@d7 1
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'''libarchive'''(3)
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'''libarchive'''(3)
d30 1
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formats and a subset of the legacy GNU tar format.
a39 1
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'''libarchive'''(3)
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'''libarchive'''(3)
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'''libarchive'''(3)
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'''SVR4'''
d250 2
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'''echo'''(1),
'''mkdir'''(1),
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'''sed'''(1).
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'''sh'''(1)
d261 1
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'''uuencode'''(1)
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'''ar'''(1)
d349 1
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'''ld'''(1).
d362 4
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if they provide a filename table to be written into
the archive before any of the entries.
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'''mtree'''(5)
d379 1
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'''mtree'''(8),
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'''archive_write_set_options'''(3)
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XXX Information about libarchive's LHA support XXX
=== CAB===
XXX Information about libarchive's CAB support XXX
=== XAR===
XXX Information about libarchive's XAR support XXX
d422 7
d430 10
a439 10
'''ar'''(1),
'''cpio'''(1),
'''mkisofs'''(1),
'''shar'''(1),
'''tar'''(1),
'''zip'''(1),
'''zlib'''(3),
'''cpio'''(5),
'''mtree'''(5),
'''tar'''(5)
@
1.1
log
@Initial revision
@
text
@d1 403
a403 327
#summary libarchive-formats 5 manual page
== NAME ==
*libarchive-formats*
- archive formats supported by the libarchive library
== DESCRIPTION ==
The
*libarchive*(3)
library reads and writes a variety of streaming archive formats.
Generally speaking, all of these archive formats consist of a series of
"entries".
Each entry stores a single file system object, such as a file, directory,
or symbolic link.
The following provides a brief description of each format supported
by libarchive, with some information about recognized extensions or
limitations of the current library support.
Note that just because a format is supported by libarchive does not
imply that a program that uses libarchive will support that format.
Applications that use libarchive specify which formats they wish
to support, though many programs do use libarchive convenience
functions to enable all supported formats.
=== Tar Formats===
The
*libarchive*(3)
library can read most tar archives.
However, it only writes POSIX-standard
"ustar"
and
"pax interchange"
formats.
All tar formats store each entry in one or more 512-byte records.
The first record is used for file metadata, including filename,
timestamp, and mode information, and the file data is stored in
subsequent records.
Later variants have extended this by either appropriating undefined
areas of the header record, extending the header to multiple records,
or by storing special entries that modify the interpretation of
subsequent entries.
- *gnutar*
-
The
*libarchive*(3)
library can read GNU-format tar archives.
It currently supports the most popular GNU extensions, including
modern long filename and linkname support, as well as atime and ctime data.
The libarchive library does not support multi-volume
archives, nor the old GNU long filename format.
It can read GNU sparse file entries, including the new POSIX-based
formats, but cannot write GNU sparse file entries.
- *pax*
-
The
*libarchive*(3)
library can read and write POSIX-compliant pax interchange format
archives.
Pax interchange format archives are an extension of the older ustar
format that adds a separate entry with additional attributes stored
as key/value pairs immediately before each regular entry.
The presence of these additional entries is the only difference between
pax interchange format and the older ustar format.
The extended attributes are of unlimited length and are stored
as UTF-8 Unicode strings.
Keywords defined in the standard are in all lowercase; vendors are allowed
to define custom keys by preceding them with the vendor name in all uppercase.
When writing pax archives, libarchive uses many of the SCHILY keys
defined by Joerg Schilling's
"star"
archiver and a few LIBARCHIVE keys.
The libarchive library can read most of the SCHILY keys
and most of the GNU keys introduced by GNU tar.
It silently ignores any keywords that it does not understand.
- *restricted* pax
-
The libarchive library can also write pax archives in which it
attempts to suppress the extended attributes entry whenever
possible.
The result will be identical to a ustar archive unless the
extended attributes entry is required to store a long file
name, long linkname, extended ACL, file flags, or if any of the standard
ustar data (user name, group name, UID, GID, etc) cannot be fully
represented in the ustar header.
In all cases, the result can be dearchived by any program that
can read POSIX-compliant pax interchange format archives.
Programs that correctly read ustar format (see below) will also be
able to read this format; any extended attributes will be extracted as
separate files stored in
_PaxHeader_
directories.
- *ustar*
-
The libarchive library can both read and write this format.
This format has the following limitations:
-
Device major and minor numbers are limited to 21 bits.
Nodes with larger numbers will not be added to the archive.
-
Path names in the archive are limited to 255 bytes.
(Shorter if there is no / character in exactly the right place.)
-
Symbolic links and hard links are stored in the archive with
the name of the referenced file.
This name is limited to 100 bytes.
-
Extended attributes, file flags, and other extended
security information cannot be stored.
-
Archive entries are limited to 8 gigabytes in size.
Note that the pax interchange format has none of these restrictions.
The libarchive library also reads a variety of commonly-used extensions to
the basic tar format.
These extensions are recognized automatically whenever they appear.
- Numeric extensions.
-
The POSIX standards require fixed-length numeric fields to be written with
some character position reserved for terminators.
Libarchive allows these fields to be written without terminator characters.
This extends the allowable range; in particular, ustar archives with this
extension can support entries up to 64 gigabytes in size.
Libarchive also recognizes base-256 values in most numeric fields.
This essentially removes all limitations on file size, modification time,
and device numbers.
- Solaris extensions
-
Libarchive recognizes ACL and extended attribute records written
by Solaris tar.
Currently, libarchive only has support for old-style ACLs; the
newer NFSv4 ACLs are recognized but discarded.
The first tar program appeared in Seventh Edition Unix in 1979.
The first official standard for the tar file format was the
"ustar"
(Unix Standard Tar) format defined by POSIX in 1988.
POSIX.1-2001 extended the ustar format to create the
"pax interchange"
format.
=== Cpio Formats===
The libarchive library can read a number of common cpio variants and can write
"odc"
and
"newc"
format archives.
A cpio archive stores each entry as a fixed-size header followed
by a variable-length filename and variable-length data.
Unlike the tar format, the cpio format does only minimal padding
of the header or file data.
There are several cpio variants, which differ primarily in
how they store the initial header: some store the values as
octal or hexadecimal numbers in ASCII, others as binary values of
varying byte order and length.
- *binary*
-
The libarchive library transparently reads both big-endian and little-endian
variants of the original binary cpio format.
This format used 32-bit binary values for file size and mtime,
and 16-bit binary values for the other fields.
- *odc*
-
The libarchive library can both read and write this
POSIX-standard format, which is officially known as the
"cpio interchange format"
or the
"octet-oriented cpio archive format"
and sometimes unofficially referred to as the
"old character format".
This format stores the header contents as octal values in ASCII.
It is standard, portable, and immune from byte-order confusion.
File sizes and mtime are limited to 33 bits (8GB file size),
other fields are limited to 18 bits.
- *SVR4*
-
The libarchive library can read both CRC and non-CRC variants of
this format.
The SVR4 format uses eight-digit hexadecimal values for
all header fields.
This limits file size to 4GB, and also limits the mtime and
other fields to 32 bits.
The SVR4 format can optionally include a CRC of the file
contents, although libarchive does not currently verify this CRC.
Cpio first appeared in PWB/UNIX 1.0, which was released within
AT&T in 1977.
PWB/UNIX 1.0 formed the basis of System III Unix, released outside
of AT&T in 1981.
This makes cpio older than tar, although cpio was not included
in Version 7 AT&T Unix.
As a result, the tar command became much better known in universities
and research groups that used Version 7.
The combination of the
*find*
and
*cpio*
utilities provided very precise control over file selection.
Unfortunately, the format has many limitations that make it unsuitable
for widespread use.
Only the POSIX format permits files over 4GB, and its 18-bit
limit for most other fields makes it unsuitable for modern systems.
In addition, cpio formats only store numeric UID/GID values (not
usernames and group names), which can make it very difficult to correctly
transfer archives across systems with dissimilar user numbering.
=== Shar Formats===
A
"shell archive"
is a shell script that, when executed on a POSIX-compliant
system, will recreate a collection of file system objects.
The libarchive library can write two different kinds of shar archives:
- *shar*
-
The traditional shar format uses a limited set of POSIX
commands, including
*echo*(1),
*mkdir*(1),
and
*sed*(1).
It is suitable for portably archiving small collections of plain text files.
However, it is not generally well-suited for large archives
(many implementations of
*sh*(1)
have limits on the size of a script) nor should it be used with non-text files.
- *shardump*
-
This format is similar to shar but encodes files using
*uuencode*(1)
so that the result will be a plain text file regardless of the file contents.
It also includes additional shell commands that attempt to reproduce as
many file attributes as possible, including owner, mode, and flags.
The additional commands used to restore file attributes make
shardump archives less portable than plain shar archives.
=== ISO9660 format===
Libarchive can read and extract from files containing ISO9660-compliant
CDROM images.
In many cases, this can remove the need to burn a physical CDROM
just in order to read the files contained in an ISO9660 image.
It also avoids security and complexity issues that come with
virtual mounts and loopback devices.
Libarchive supports the most common Rockridge extensions and has partial
support for Joliet extensions.
If both extensions are present, the Joliet extensions will be
used and the Rockridge extensions will be ignored.
In particular, this can create problems with hardlinks and symlinks,
which are supported by Rockridge but not by Joliet.
=== Zip format===
Libarchive can read and write zip format archives that have
uncompressed entries and entries compressed with the
"deflate"
algorithm.
Older zip compression algorithms are not supported.
It can extract jar archives, archives that use Zip64 extensions and many
self-extracting zip archives.
Libarchive reads Zip archives as they are being streamed,
which allows it to read archives of arbitrary size.
It currently does not use the central directory; this
limits libarchive's ability to support some self-extracting
archives and ones that have been modified in certain ways.
=== Archive (library) file format===
The Unix archive format (commonly created by the
*ar*(1)
archiver) is a general-purpose format which is
used almost exclusively for object files to be
read by the link editor
*ld*(1).
The ar format has never been standardised.
There are two common variants:
the GNU format derived from SVR4,
and the BSD format, which first appeared in 4.4BSD.
The two differ primarily in their handling of filenames
longer than 15 characters:
the GNU/SVR4 variant writes a filename table at the beginning of the archive;
the BSD format stores each long filename in an extension
area adjacent to the entry.
Libarchive can read both extensions,
including archives that may include both types of long filenames.
Programs using libarchive can write GNU/SVR4 format
if they provide a filename table to be written into
the archive before any of the entries.
Any entries whose names are not in the filename table
will be written using BSD-style long filenames.
This can cause problems for programs such as
GNU ld that do not support the BSD-style long filenames.
=== mtree===
Libarchive can read and write files in
*mtree*(5)
format.
This format is not a true archive format, but rather a textual description
of a file hierarchy in which each line specifies the name of a file and
provides specific metadata about that file.
Libarchive can read all of the keywords supported by both
the NetBSD and FreeBSD versions of
*mtree*(1),
although many of the keywords cannot currently be stored in an
*archive_entry*
object.
When writing, libarchive supports use of the
*archive_write_set_options*(3)
interface to specify which keywords should be included in the
output.
If libarchive was compiled with access to suitable
cryptographic libraries (such as the OpenSSL libraries),
it can compute hash entries such as
*sha512*
or
*md5*
from file data being written to the mtree writer.
When reading an mtree file, libarchive will locate the corresponding
files on disk using the
*contents*
keyword if present or the regular filename.
If it can locate and open the file on disk, it will use that
to fill in any metadata that is missing from the mtree file
and will read the file contents and return those to the program
using libarchive.
If it cannot locate and open the file on disk, libarchive
will return an error for any attempt to read the entry
body.
== SEE ALSO ==
*ar*(1),
*cpio*(1),
*mkisofs*(1),
*shar*(1),
*tar*(1),
*zip*(1),
*zlib*(3),
*cpio*(5),
*mtree*(5),
*tar*(5)
@
1.1.1.1
log
@Import libarchive 2.8.0:
- Infrastructure:
- Allow command line tools as fallback for missing compression
libraries. If compiled without gzip for example, gunzip will
be used automatically.
- Improved support for a number of platforms like high-resolution
timestamps and Extended Attributes on various Unix systems
- New convience interface for creating archives based on disk content,
complement of the archive_write_disk interface.
- Frontends:
- bsdcpio ready for public consumption
- hand-written date parser replaces the yacc code
- Filter system:
- Simplified read filter chains
- Option support for filters
- LZMA, XZ, uudecode handled
- Format support:
- Write support for mtree files based on file system or archive
content
- Basic read support for Joliet
- Write support for zip files
- Write support for shar archives, both text-only and binary-safe
@
text
@@
1.1.1.2
log
@Import libarchive-3.2.1:
- security fixes and other bugfixes
- support for multhreading in xz 5.2+
@
text
@d1 327
a327 439
LIBARCHIVE-FORMATS(5) manual page
== NAME ==
'''libarchive-formats'''
- archive formats supported by the libarchive library
== DESCRIPTION ==
The
[[ManPageibarchive3]]
library reads and writes a variety of streaming archive formats.
Generally speaking, all of these archive formats consist of a series of
"entries".
Each entry stores a single file system object, such as a file, directory,
or symbolic link.
The following provides a brief description of each format supported
by libarchive, with some information about recognized extensions or
limitations of the current library support.
Note that just because a format is supported by libarchive does not
imply that a program that uses libarchive will support that format.
Applications that use libarchive specify which formats they wish
to support, though many programs do use libarchive convenience
functions to enable all supported formats.
=== Tar Formats===
The
[[ManPageibarchive3]]
library can read most tar archives.
It can write POSIX-standard
"ustar"
and
"pax interchange"
formats as well as v7 tar format and a subset of the legacy GNU tar format.
All tar formats store each entry in one or more 512-byte records.
The first record is used for file metadata, including filename,
timestamp, and mode information, and the file data is stored in
subsequent records.
Later variants have extended this by either appropriating undefined
areas of the header record, extending the header to multiple records,
or by storing special entries that modify the interpretation of
subsequent entries.
- '''gnutar'''
-
The
[[ManPageibarchive3]]
library can read most GNU-format tar archives.
It currently supports the most popular GNU extensions, including
modern long filename and linkname support, as well as atime and ctime data.
The libarchive library does not support multi-volume
archives, nor the old GNU long filename format.
It can read GNU sparse file entries, including the new POSIX-based
formats.
The
[[ManPageibarchive3]]
library can write GNU tar format, including long filename
and linkname support, as well as atime and ctime data.
- '''pax'''
-
The
[[ManPageibarchive3]]
library can read and write POSIX-compliant pax interchange format
archives.
Pax interchange format archives are an extension of the older ustar
format that adds a separate entry with additional attributes stored
as key/value pairs immediately before each regular entry.
The presence of these additional entries is the only difference between
pax interchange format and the older ustar format.
The extended attributes are of unlimited length and are stored
as UTF-8 Unicode strings.
Keywords defined in the standard are in all lowercase; vendors are allowed
to define custom keys by preceding them with the vendor name in all uppercase.
When writing pax archives, libarchive uses many of the SCHILY keys
defined by Joerg Schilling's
"star"
archiver and a few LIBARCHIVE keys.
The libarchive library can read most of the SCHILY keys
and most of the GNU keys introduced by GNU tar.
It silently ignores any keywords that it does not understand.
The pax interchange format converts filenames to Unicode
and stores them using the UTF-8 encoding.
Prior to libarchive 3.0, libarchive erroneously assumed
that the system wide-character routines natively supported
Unicode.
This caused it to mis-handle non-ASCII filenames on systems
that did not satisfy this assumption.
- '''restricted''' pax
-
The libarchive library can also write pax archives in which it
attempts to suppress the extended attributes entry whenever
possible.
The result will be identical to a ustar archive unless the
extended attributes entry is required to store a long file
name, long linkname, extended ACL, file flags, or if any of the standard
ustar data (user name, group name, UID, GID, etc) cannot be fully
represented in the ustar header.
In all cases, the result can be dearchived by any program that
can read POSIX-compliant pax interchange format archives.
Programs that correctly read ustar format (see below) will also be
able to read this format; any extended attributes will be extracted as
separate files stored in
''PaxHeader''
directories.
- '''ustar'''
-
The libarchive library can both read and write this format.
This format has the following limitations:
-
Device major and minor numbers are limited to 21 bits.
Nodes with larger numbers will not be added to the archive.
-
Path names in the archive are limited to 255 bytes.
(Shorter if there is no / character in exactly the right place.)
-
Symbolic links and hard links are stored in the archive with
the name of the referenced file.
This name is limited to 100 bytes.
-
Extended attributes, file flags, and other extended
security information cannot be stored.
-
Archive entries are limited to 8 gigabytes in size.
Note that the pax interchange format has none of these restrictions.
The ustar format is old and widely supported.
It is recommended when compatibility is the primary concern.
- '''v7'''
-
The libarchive library can read and write the legacy v7 tar format.
This format has the following limitations:
-
Only regular files, directories, and symbolic links can be archived.
Block and character device nodes, FIFOs, and sockets cannot be archived.
-
Path names in the archive are limited to 100 bytes.
-
Symbolic links and hard links are stored in the archive with
the name of the referenced file.
This name is limited to 100 bytes.
-
User and group information are stored as numeric IDs; there
is no provision for storing user or group names.
-
Extended attributes, file flags, and other extended
security information cannot be stored.
-
Archive entries are limited to 8 gigabytes in size.
Generally, users should prefer the ustar format for portability
as the v7 tar format is both less useful and less portable.
The libarchive library also reads a variety of commonly-used extensions to
the basic tar format.
These extensions are recognized automatically whenever they appear.
- Numeric extensions.
-
The POSIX standards require fixed-length numeric fields to be written with
some character position reserved for terminators.
Libarchive allows these fields to be written without terminator characters.
This extends the allowable range; in particular, ustar archives with this
extension can support entries up to 64 gigabytes in size.
Libarchive also recognizes base-256 values in most numeric fields.
This essentially removes all limitations on file size, modification time,
and device numbers.
- Solaris extensions
-
Libarchive recognizes ACL and extended attribute records written
by Solaris tar.
Currently, libarchive only has support for old-style ACLs; the
newer NFSv4 ACLs are recognized but discarded.
The first tar program appeared in Seventh Edition Unix in 1979.
The first official standard for the tar file format was the
"ustar"
(Unix Standard Tar) format defined by POSIX in 1988.
POSIX.1-2001 extended the ustar format to create the
"pax interchange"
format.
=== Cpio Formats===
The libarchive library can read a number of common cpio variants and can write
"odc"
and
"newc"
format archives.
A cpio archive stores each entry as a fixed-size header followed
by a variable-length filename and variable-length data.
Unlike the tar format, the cpio format does only minimal padding
of the header or file data.
There are several cpio variants, which differ primarily in
how they store the initial header: some store the values as
octal or hexadecimal numbers in ASCII, others as binary values of
varying byte order and length.
- '''binary'''
-
The libarchive library transparently reads both big-endian and little-endian
variants of the original binary cpio format.
This format used 32-bit binary values for file size and mtime,
and 16-bit binary values for the other fields.
- '''odc'''
-
The libarchive library can both read and write this
POSIX-standard format, which is officially known as the
"cpio interchange format"
or the
"octet-oriented cpio archive format"
and sometimes unofficially referred to as the
"old character format".
This format stores the header contents as octal values in ASCII.
It is standard, portable, and immune from byte-order confusion.
File sizes and mtime are limited to 33 bits (8GB file size),
other fields are limited to 18 bits.
- '''SVR4/newc'''
-
The libarchive library can read both CRC and non-CRC variants of
this format.
The SVR4 format uses eight-digit hexadecimal values for
all header fields.
This limits file size to 4GB, and also limits the mtime and
other fields to 32 bits.
The SVR4 format can optionally include a CRC of the file
contents, although libarchive does not currently verify this CRC.
Cpio first appeared in PWB/UNIX 1.0, which was released within
AT&T in 1977.
PWB/UNIX 1.0 formed the basis of System III Unix, released outside
of AT&T in 1981.
This makes cpio older than tar, although cpio was not included
in Version 7 AT&T Unix.
As a result, the tar command became much better known in universities
and research groups that used Version 7.
The combination of the
'''find'''
and
'''cpio'''
utilities provided very precise control over file selection.
Unfortunately, the format has many limitations that make it unsuitable
for widespread use.
Only the POSIX format permits files over 4GB, and its 18-bit
limit for most other fields makes it unsuitable for modern systems.
In addition, cpio formats only store numeric UID/GID values (not
usernames and group names), which can make it very difficult to correctly
transfer archives across systems with dissimilar user numbering.
=== Shar Formats===
A
"shell archive"
is a shell script that, when executed on a POSIX-compliant
system, will recreate a collection of file system objects.
The libarchive library can write two different kinds of shar archives:
- '''shar'''
-
The traditional shar format uses a limited set of POSIX
commands, including
[[echo(1)|http://www.freebsd.org/cgi/man.cgi?query=echo&sektion=1]],
[[mkdir(1)|http://www.freebsd.org/cgi/man.cgi?query=mkdir&sektion=1]],
and
[[sed(1)|http://www.freebsd.org/cgi/man.cgi?query=sed&sektion=1]].
It is suitable for portably archiving small collections of plain text files.
However, it is not generally well-suited for large archives
(many implementations of
[[sh(1)|http://www.freebsd.org/cgi/man.cgi?query=sh&sektion=1]]
have limits on the size of a script) nor should it be used with non-text files.
- '''shardump'''
-
This format is similar to shar but encodes files using
[[uuencode(1)|http://www.freebsd.org/cgi/man.cgi?query=uuencode&sektion=1]]
so that the result will be a plain text file regardless of the file contents.
It also includes additional shell commands that attempt to reproduce as
many file attributes as possible, including owner, mode, and flags.
The additional commands used to restore file attributes make
shardump archives less portable than plain shar archives.
=== ISO9660 format===
Libarchive can read and extract from files containing ISO9660-compliant
CDROM images.
In many cases, this can remove the need to burn a physical CDROM
just in order to read the files contained in an ISO9660 image.
It also avoids security and complexity issues that come with
virtual mounts and loopback devices.
Libarchive supports the most common Rockridge extensions and has partial
support for Joliet extensions.
If both extensions are present, the Joliet extensions will be
used and the Rockridge extensions will be ignored.
In particular, this can create problems with hardlinks and symlinks,
which are supported by Rockridge but not by Joliet.
Libarchive reads ISO9660 images using a streaming strategy.
This allows it to read compressed images directly
(decompressing on the fly) and allows it to read images
directly from network sockets, pipes, and other non-seekable
data sources.
This strategy works well for optimized ISO9660 images created
by many popular programs.
Such programs collect all directory information at the beginning
of the ISO9660 image so it can be read from a physical disk
with a minimum of seeking.
However, not all ISO9660 images can be read in this fashion.
Libarchive can also write ISO9660 images.
Such images are fully optimized with the directory information
preceding all file data.
This is done by storing all file data to a temporary file
while collecting directory information in memory.
When the image is finished, libarchive writes out the
directory structure followed by the file data.
The location used for the temporary file can be changed
by the usual environment variables.
=== Zip format===
Libarchive can read and write zip format archives that have
uncompressed entries and entries compressed with the
"deflate"
algorithm.
Other zip compression algorithms are not supported.
It can extract jar archives, archives that use Zip64 extensions and
self-extracting zip archives.
Libarchive can use either of two different strategies for
reading Zip archives:
a streaming strategy which is fast and can handle extremely
large archives, and a seeking strategy which can correctly
process self-extracting Zip archives and archives with
deleted members or other in-place modifications.
The streaming reader processes Zip archives as they are read.
It can read archives of arbitrary size from tape or
network sockets, and can decode Zip archives that have
been separately compressed or encoded.
However, self-extracting Zip archives and archives with
certain types of modifications cannot be correctly
handled.
Such archives require that the reader first process the
Central Directory, which is ordinarily located
at the end of a Zip archive and is thus inaccessible
to the streaming reader.
If the program using libarchive has enabled seek support, then
libarchive will use this to processes the central directory first.
In particular, the seeking reader must be used to
correctly handle self-extracting archives.
Such archives consist of a program followed by a regular
Zip archive.
The streaming reader cannot parse the initial program
portion, but the seeking reader starts by reading the
Central Directory from the end of the archive.
Similarly, Zip archives that have been modified in-place
can have deleted entries or other garbage data that
can only be accurately detected by first reading the
Central Directory.
=== Archive (library) file format===
The Unix archive format (commonly created by the
[[ar(1)|http://www.freebsd.org/cgi/man.cgi?query=ar&sektion=1]]
archiver) is a general-purpose format which is
used almost exclusively for object files to be
read by the link editor
[[ld(1)|http://www.freebsd.org/cgi/man.cgi?query=ld&sektion=1]].
The ar format has never been standardised.
There are two common variants:
the GNU format derived from SVR4,
and the BSD format, which first appeared in 4.4BSD.
The two differ primarily in their handling of filenames
longer than 15 characters:
the GNU/SVR4 variant writes a filename table at the beginning of the archive;
the BSD format stores each long filename in an extension
area adjacent to the entry.
Libarchive can read both extensions,
including archives that may include both types of long filenames.
Programs using libarchive can write GNU/SVR4 format
if they provide an entry called
''//''
containing a filename table to be written into the archive
before any of the entries.
Any entries whose names are not in the filename table
will be written using BSD-style long filenames.
This can cause problems for programs such as
GNU ld that do not support the BSD-style long filenames.
=== mtree===
Libarchive can read and write files in
[[ManPageMtree5]]
format.
This format is not a true archive format, but rather a textual description
of a file hierarchy in which each line specifies the name of a file and
provides specific metadata about that file.
Libarchive can read all of the keywords supported by both
the NetBSD and FreeBSD versions of
[[mtree(8)|http://www.freebsd.org/cgi/man.cgi?query=mtree&sektion=8]],
although many of the keywords cannot currently be stored in an
'''archive_entry'''
object.
When writing, libarchive supports use of the
[[ManPagerchiveriteetptions3]]
interface to specify which keywords should be included in the
output.
If libarchive was compiled with access to suitable
cryptographic libraries (such as the OpenSSL libraries),
it can compute hash entries such as
'''sha512'''
or
'''md5'''
from file data being written to the mtree writer.
When reading an mtree file, libarchive will locate the corresponding
files on disk using the
'''contents'''
keyword if present or the regular filename.
If it can locate and open the file on disk, it will use that
to fill in any metadata that is missing from the mtree file
and will read the file contents and return those to the program
using libarchive.
If it cannot locate and open the file on disk, libarchive
will return an error for any attempt to read the entry
body.
=== 7-Zip===
Libarchive can read and write 7-Zip format archives.
TODO: Need more information
=== CAB===
Libarchive can read Microsoft Cabinet (
"CAB )"
format archives.
TODO: Need more information.
=== LHA===
TODO: Information about libarchive's LHA support
=== RAR===
Libarchive has limited support for reading RAR format archives.
Currently, libarchive can read RARv3 format archives
which have been either created uncompressed, or compressed using
any of the compression methods supported by the RARv3 format.
Libarchive can also read self-extracting RAR archives.
=== Warc===
Libarchive can read and write
"web archives".
TODO: Need more information
=== XAR===
Libarchive can read and write the XAR format used by many Apple tools.
TODO: Need more information
== SEE ALSO ==
[[ar(1)|http://www.freebsd.org/cgi/man.cgi?query=ar&sektion=1]],
[[ManPageBsdcpio1]],
[[mkisofs(1)|http://www.freebsd.org/cgi/man.cgi?query=mkisofs&sektion=1]],
[[shar(1)|http://www.freebsd.org/cgi/man.cgi?query=shar&sektion=1]],
[[ManPageBsdtar1]],
[[zip(1)|http://www.freebsd.org/cgi/man.cgi?query=zip&sektion=1]],
[[zlib(3)|http://www.freebsd.org/cgi/man.cgi?query=zlib&sektion=3]],
[[ManPageCpio5]],
[[ManPageMtree5]],
[[ManPageTar5]]
@
1.1.1.3
log
@Import libarchive-3.3.1.
@
text
@d7 1
a7 1
[[ManPageLibarchive3]]
d24 1
a24 1
[[ManPageLibarchive3]]
d43 1
a43 1
[[ManPageLibarchive3]]
d53 1
a53 1
[[ManPageLibarchive3]]
d58 1
a58 1
[[ManPageLibarchive3]]
d166 2
d384 1
a384 1
[[ManPageArchiveWriteSetOptions3]]
@
1.1.1.4
log
@Import libarchive-3.3.2 + 9de5f3 + f9dacbf:
- Support NFS4 ACLs on Linux
- Bugfixes
@
text
@d7 1
a7 1
[[ManPageibarchive3]]
d24 1
a24 1
[[ManPageibarchive3]]
d43 1
a43 1
[[ManPageibarchive3]]
d53 1
a53 1
[[ManPageibarchive3]]
d58 1
a58 1
[[ManPageibarchive3]]
d382 1
a382 1
[[ManPagerchiveriteetptions3]]
@
1.1.1.5
log
@Import libarchive 3.4.0
@
text
@d7 1
a7 1
[[ManPageLibarchive3]]
d24 1
a24 1
[[ManPageLibarchive3]]
d43 1
a43 1
[[ManPageLibarchive3]]
d53 1
a53 1
[[ManPageLibarchive3]]
d58 1
a58 1
[[ManPageLibarchive3]]
d382 1
a382 1
[[ManPageArchiveWriteSetOptions3]]
@
1.1.1.6
log
@Import libarchive 3.7.2
@
text
@d176 13
a188 8
The libarchive library can read and write a number of common cpio
variants. A cpio archive stores each entry as a fixed-size header
followed by a variable-length filename and variable-length data.
Unlike the tar format, the cpio format does only minimal padding of
the header or file data. There are several cpio variants, which
differ primarily in how they store the initial header: some store the
values as octal or hexadecimal numbers in ASCII, others as binary
values of varying byte order and length.
d191 4
a194 9
The libarchive library transparently reads both big-endian and
little-endian variants of the the two binary cpio formats; the
original one from PWB/UNIX, and the later, more widely used, variant.
This format used 32-bit binary values for file size and mtime, and
16-bit binary values for the other fields. The formats support only
the file types present in UNIX at the time of their creation. File
sizes are limited to 24 bits in the PWB format, because of the limits
of the file system, and to 31 bits in the newer binary format, where
signed 32 bit longs were used.
d196 2
a197 1
This is the POSIX standardized format, which is officially known as the
@
1.1.1.7
log
@libarchive: import version 3.8.0
Libarchive 3.8.0 is a feature and bugfix release.
New features:
bsdtar: support --mtime and --clamp-mtime
lib: mbedtls 3.x compatibility
7-zip reader: improve self-extracting archive detection
xar: xmllite support for the XAR reader and writer
zip writer: added XZ, LZMA, ZSTD and BZIP2 support
zip writer: added LZMA + RISCV BCJ filter
Notable security fixes:
rar: do not skip past EOF while reading
rar: fix double free with over 4 billion nodes
rar: fix heap-buffer-overflow
warc: prevent signed integer overflow
tar: fix overflow in build_ustar_entry
Notable bugfixes:
bsdtar: don't hardlink negative inode files together
gz: allow setting the original filename for gzip compressed files
lib: improve lseek handling
lib: support @@-prefixed Unix epoch timestamps as date strings
rar: support large headers on 32 bit systems
tar reader: Improve LFS support on 32 bit systems
@
text
@a303 12
,
"LZMA"
,
"XZ"
,
"BZIP2"
and
"ZSTD"
algorithms.
Libarchive can also read, but not write, zip format archives that
have entries compressed with the
"PPMd"
d306 2
a307 6
The extensions supported by libarchive are Zip64, Libarchive's
extensions to better support streaming, PKZIP's traditional
ZIP encryption, Info-ZIP's Unix extra fields, extra time, and
Unicode path, as well as WinZIP's AES encryption.
It can extract jar archives, __MACOSX resource forks extension
for OS X, and self-extracting zip archives.
@
1.1.1.8
log
@libarchive: import 3.8.8
@
text
@d187 1
a187 1
little-endian variants of the two binary cpio formats; the
@
1.1.1.9
log
@libarchive: import version 3.8.10
@
text
@d343 1
a343 1
libarchive will use this to process the central directory first.
@