libisofs/doc/susp_aaip_isofs_names.txt

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Arbitrary Attribute Interchange Protocol
Interchange of Persistent File Attributes
Directory of Namespace "isofs."
by Thomas Schmitt - mailto:scdbackup@gmx.net
Libburnia project - mailto:libburn-hackers@pykix.org
The following names are defined for AAIP namespace "isofs." as mentioned in
specification of AAIP :
-------------------------------------------------------------------------------
Name:
isofs.ca
Purpose:
Records the range of checksummed image data (START, END), the number
of checksum items (COUNT), the number of bytes in a single checksum item
(SIZE), and the name of the checksum algorithm (CHECKSUM_TYPE).
END is also the block address of the start of the checksum recording
area in the image.
See also isofs.cx .
This attribute shall eventually be attached to the root directory entry
and be global for the whole image.
Format of Value:
START_LEN | START_BYTES | END_LEN | END_BYTES |
COUNT_LEN | COUNT_BYTES | SIZE_LEN | SIZE_BYTES | CHECKSUM_TYPE
Each number is encoded as _LEN byte and _BYTES value string.
The _LEN fields comply to ISO 9660 Format section 7.1.1.
The byte strings START_BYTES, END_BYTES, COUNT_BYTES, SIZE_BYTES begin
with the most significant byte. Leading zero bytes are allowed.
CHECKSUM_TYPE consists of the bytes after
START_LEN + END_LEN + COUNT_LEN + SIZE_LEN + 4.
It shall be a string of printable characters without terminating 0-byte.
Type names shall be registered here.
For now there is:
"MD5" 128 bit message digest, see RFC 1321, see man md5sum
Example:
LBA range 32 to 1000000 , 520 checksums recorded, MD5
{ 1, 32,
3, 15, 66, 64,
2, 2, 8,
1, 16,
'M', 'D', '5' }
or
{ 4, 0, 0, 0, 32,
4, 0, 15, 66, 64,
4, 0, 0, 2, 8,
1, 16,
'M', 'D', '5' }
Registered:
16 Jul 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.cs
Purpose:
Records the name of the character set that was used as output character
set when writing the RRIP name tree of the ISO 9660 image. It shall be
suitable as parameter for function iconv_open(3).
This attribute shall eventually be attached to the root directory entry
and be global for the whole image.
Format of Value:
Shall hold the character set name without terminating 0-byte.
Example:
{ 'I', 'S', 'O', '-', '8', '8', '5', '9' , '-', '1' }
Registered:
18 Mar 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.cx
Purpose:
Records the index of the file's checksum in the checksum area at the
end of the image. The byte address of the checksum is
checksum_area_lba * 2048 + isofs.cx * checksum_size
Default checksum algorithm is MD5 with a size of 16 byte.
See also isofs.ca .
Format of Value:
A byte string which begins with the most significant byte.
Example:
Index 123456
{ 1, 226, 64 }
Registered:
16 Jul 2009 by Thomas Schmitt for libisofs.
-------------------------------------------------------------------------------
Name:
isofs.di
Purpose:
Records .st_dev and .st_ino of struct stat of the file source in the
local filesystem. See man 2 stat.
Format of Value:
DEV_LEN | DEV_BYTES | INO_LEN | INO_BYTES
The _LEN fields comply to ISO 9660 Format section 7.1.1.
The byte strings begin with the most significant byte.
Example:
Device number 2001, inode number 176343
{ 2, 7, 209,
3, 2, 176, 215 }
Registered:
17 Feb 2009 by Thomas Schmitt for xorriso.
-------------------------------------------------------------------------------
Name:
isofs.st
Purpose:
Records a time point at least 1 second before any nodes were added to a
freshly loaded or created ISO image. Nodes in the image which have
younger timestamps are suspect to have changed their content during
image production and might bear inconsistent content.
The RRIP timestamps have a blind second during which a change after
node registration would not be recognizable for incremental backups
which are based in "isofs.di" rather than on content comparison.
This attribute shall eventually be attached to the root directory entry
and be global for the whole image.
Format of Value:
Shall hold UTC seconds since 1970 as decimal number string without
terminating 0-byte.
Example:
{ '1', '2', '3', '8', '7', '4', '2', '2', '9', '6' }
Registered:
03 Apr 2009 by Thomas Schmitt for xorriso.
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This text is under
Copyright (c) 2009 - 2011 Thomas Schmitt <scdbackup@gmx.net>
It shall only be modified in sync with libisofs and other software which
makes use of AAIP. Please mail change requests to mailing list
<libburn-hackers@pykix.org> or to the copyright holder in private.
Only if you cannot reach the copyright holder for at least one month it is
permissible to modify this text under the same license as the affected
copy of libisofs.
If you do so, you commit yourself to taking reasonable effort to stay in
sync with the other interested users of this text.