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Made AAIP 1.0 official, mentioned it in aaip source files,

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and claimed copyright and GPLv2 on aaip source files.
This commit is contained in:
Thomas Schmitt
2009-02-19 09:36:22 +01:00
parent 0e0ecc1d00
commit 97d885fc9a
6 changed files with 112 additions and 103 deletions
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176
doc/susp_aaip_0_2.txt → doc/susp_aaip_1_0.txt
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@ -2,8 +2,9 @@
Arbitrary Attribute Interchange Protocol
Draft version 0.2
Feb 10 2009
Version 1.0
Feb 19 2009
Interchange of Persistent File Attributes
@ -48,9 +49,8 @@ an even number of components. Each two consequtive components form a pair of
Name and Value.
The empty name indicates that the value is a compact representation of ACLs.
Names must not contain byte value 0x00. Names which begin by bytes 0x01 to 0x1f
represent names in particular name spaces. See below: Name Spaces.
represent names in particular namespaces. See below: Namespaces.
The meaning of any other names or name parts is not specified by this document.
All AA entries except the last one shall have the CONTINUE flag set. An AA
@ -137,29 +137,29 @@ Example: Two pairs of "name"="long...content" and "one"="more" encoded as
-------------------------------------------------------------------------------
Name Spaces
Namespaces
AAIP provides a short notation for namespaces which uses a single non-printable
byte at the start of the name.
Reserved start bytes of names are
0x01 to 0x1F
The names of extended file attributes are traditionally organized in name
spaces, which get expressed as first part of an attribute name up to a
The names of extended file attributes are traditionally organized in
namespaces, which get expressed as first part of an attribute name up to a
period "." character. It is also tradition that names are printable text,
single words and especially contain no 0-bytes.
AAIP does not enforce the use of any name space but it urges that names in the
following registered name spaces are used according to traditions.
AAIP does not enforce the use of any namespace but it urges that names in the
following registered namespaces are used according to traditions.
The name spaces "system." and "user." are available with many file system
The namespaces "system." and "user." are available with many file system
types. "system." is file system dependent and often restricted in the
choice of names. "user." is portable and allows to choose about any name.
Name space "isofs." is defined for internal use of AAIP enhanced ISO 9660
file systems. Names in this name space should be registered at libburnia.org.
Namespace "isofs." is defined for internal use of AAIP enhanced ISO 9660
file systems. Names in this namespace should be registered at libburnia.org.
Further name spaces may be registered at libburnia.org.
Further namespaces may be registered at libburnia.org.
The reserved start bytes of names have the following meaning
0x01 escape reserved character at start of name
@ -169,12 +169,12 @@ The reserved start bytes of names have the following meaning
0x05 to 0x1F shall not be used yet.
Examples:
Name "user.abc"
0, 4, 0x03, 'a', 'b', 'c'
Name "user.abc" with and without short notation. Both is allowed.
0, 4, 0x03, 'a', 'b', 'c'
0 8, 'u', 's', 'e', 'r', '.', 'a', 'b', 'c'
Name "\003abc" (if really desired)
0, 5, 0x01, 0x03, 'a', 'b', 'c'
Default mapping of AAIP name component record {0, 4, 0x0f, 'a', 'b', 'c'}
"user.aaip0F_abc"
0, 5, 0x01, 0x03, 'a', 'b', 'c'
-------------------------------------------------------------------------------
@ -192,32 +192,32 @@ The Value shall be an arbitrary number of ACL Entries:
3 QUALIFIER indicates that one or more Qualifier Records follow
4 - 7 TYPE
shall contain the tag type of the ACL entry as four bit code:
0 TRANSLATE entry for a global map of name to numeric id
1 ACL_USER_OBJ permissions of owning user (as of PX entry)
2 ACL_USER of arbitrary user, with name as qualifier
3 ACL_GROUP_OBJ permissions of owning group (as of PX entry)
4 ACL_GROUP of arbitrary group, with name as qualifier
5 ACL_MASK restricts 2, 3, and 4 via logical AND
6 ACL_OTHER permissions of non-listed, non-owning users
8 SWITCH_MARK switch from "access" ACL to "default" ACL
10 ACL_USER_N like 2, with numeric user id as qualifier
12 ACL_GROUP_N like 4, with numeric group id as qualifier
15 FUTURE_VERSION will indicate that this document
0 TRANSLATE Entry for a global map of name to numeric id
Qualifier is a record of number and text
1 ACL_USER_OBJ Permissions of owning user (as of PX entry)
3 ACL_GROUP_OBJ Permissions of owning group (as of PX entry)
5 ACL_MASK Restricts 10, 3, and 12 via logical AND
6 ACL_OTHER Permissions of non-listed, non-owning users
8 SWITCH_MARK Switch from "access" ACL to "default" ACL
10 ACL_USER_N Permissions of arbitrary user. Qualifier is
the numeric user id (max. 4 bytes).
12 ACL_GROUP_N Permissions of arbitrary group. Qualifier is
the numeric group id (max. 4 bytes).
15 FUTURE_VERSION Will indicate that this document
does not apply to the entry.
The other values are reserved. Readers shall ignore them if
they are not aware of updates of this document which would
assign a meaning to them.
The entries ACL_USER_OBJ, ACL_GROUP_OBJ, ACL_OTHER must match the permission
bits of the PX entry. This shall obey the peculiar rule that
ACL_USER_OBJ must match S_IRWXU, ACL_OTHER must match S_IRWXO,
ACL_MASK - if present - must match S_IRWXG, else ACL_GROUP must match S_IRWXG.
If there is ACL_USER_OBJ or ACL_GROUP_OBJ there must also be ACL_MASK.
The entries must match the permission bits of the PX entry. This shall obey the
rule that ACL_USER_OBJ must match S_IRWXU, ACL_OTHER must match S_IRWXO,
ACL_MASK - if present - must match S_IRWXG, else ACL_GROUP_OBJ must match
S_IRWXG. If there is ACL_USER_N or ACL_GROUP_N there must also be ACL_MASK.
A numeric qualifier is a binary number of variable length. The Most Significant
Byte comes first. The number shall be the "POSIX File User ID" resp.
"POSIX File Group ID" as also used in RRIP PX entries. The ids of owning user
and owning group shall be taken from the PX entry of the file object.
A numeric qualifier is a binary number of variable length up to 4 bytes. The
Most Significant Byte comes first. The number shall be the "POSIX File User ID"
resp. "POSIX File Group ID" as also used in RRIP PX entries. The ids of owning
user and owning group shall be taken from the PX entry of the file object.
Optional TRANSLATE entries may associate user or group names with numeric
ids to allow the reading system to remap the numeric ids. See below.
@ -226,12 +226,10 @@ interpret them.
The ACL entries belong to the "access" ACL of a file object. An optional
SWITCH_MARK entry may direct further entries to the "default" ACL which
is defined for directory objects. The switching is controlled by the EXEC bit.
0 "access" ACL
1 "default" ACL
The bits for WRITE, READ, QUALIFIER shall be 0 with SWITCH_MARK.
is defined for directory objects. The EXEC bit of SWITCH_MARK shall be 1.
The bits for WRITE, READ, QUALIFIER shall be 0.
The eventually needed qualifier is stored in one or more Qualifier Records.
An eventually needed qualifier is stored in one or more Qualifier Records.
[b] "BP 2 - Qualifier Record Head" shall be present only if QUALIFIER is set
to 1. It shall give the number of Qualifier Bytes and eventually
@ -250,38 +248,29 @@ The eventually needed qualifier is stored in one or more Qualifier Records.
Example: From man 5 acl: u::rw-,u:lisa:rw-,g::r--,g:toolies:rw-,m::r--,o::r--
{ 'A', 'A', 28, 1, 0,
"lisa" has user number 123, "toolies" has group number 65534
{ 'A', 'A', 20, 1, 0,
0, 0,
0, 19, 0x16,
0x2E, 4, 'l', 'i', 's', 'a',
0x34,
0x4E, 7, 't', 'o', 'o', 'l', 'i', 'e', 's',
0x54,
0x64 }
Example: An entry with very long qualifier u:His_Excellency_..._the_Boss:r--
0x2C, 255, 'H', 'i', 's', '_', 'E', 'x', 'c', 'e', 'l', 'e',
... 117 more bytes ...,
8, 't', 'h', 'e', '_', 'B', 'o', 's', 's',
Example: User number 71 in numerical form gets rwx
0xAF, 1, 71,
Group number 65534 gets r-x
0xCD, 2, 255, 254,
0, 11, 0x16,
0xAE, 1, 123,
0x34,
0xCE, 2, 255, 254,
0x54,
0x64 }
Example: "Access" ACL and "default" ACL (0x81 is the switch mark)
u::rwx,g::r-x,o::r-x, du::rwx,dg::r-x,dm::rwx,do::r-x,du:lisa:rwx
{ 'A', 'A', 20, 1, 0,
0, 0,
0, 11, 0x17, 0x35, 0x65,
0x81,
0x17, 0x35, 0x57, 0x65,
0xA7, 1, 123 }
-------------------------------------------------------------------------------
About Names and Numeric Identifiers
Association of Names and Numeric Identifiers
It makes an important difference whether qualifiers are represented as names
or as id numbers. By storing names (and usually wasting space) it is possible
to control permissions in a way that is portable between uncoordinated
computers as long as the human readable user/group names are present on both
sides. POSIX File ID numbers make most sense in backups which shall be read
by the same system which wrote it.
Rock Ridge can only record POSIX File Ids but not user or group names.
The entry flag value 0x08 TRANSLATE is not a ACL entry of the hosting object
but rather a global hint about the relation of roles, names and numeric ids.
If it is recorded at all, then it shall be recorded with the first Directory
@ -306,11 +295,18 @@ The Qualifier Bytes of a TRANSLATE entry shall have the following format:
| ROLE | NUMERIC ID | NAME |
Example: User id number 1001 gets associated with user name "lisa"
Example: User id number 123 gets associated with user name "lisa"
0x08, 13, 0, 233,3,0,0, 0,0,3,233, 'l', 'i', 's', 'a',
0x08, 13, 0, 123,0,0,0, 0,0,0,123, 'l', 'i', 's', 'a',
Example: A very long qualifier naming "His_Excellency_..._the_Boss" as user #1.
This needs two qualifier records.
0x08, 255, 0, 1,0,0,0, 0,0,0,1,
'H', 'i', 's', '_', 'E', 'x', 'c', 'e', 'l', 'e',
... 108 more bytes ...
8, 't', 'h', 'e', '_', 'B', 'o', 's', 's',
-------------------------------------------------------------------------------
Specification of the ER System Use Entry Values for AAIP:
@ -324,10 +320,10 @@ and the ES entries must not be present, although SUSP-1.10 would allow ER.
The Extension Version number for this version of AAIP shall be 1.
The Extension Identifier field shall be "AAIP_0002" with Identifier Length 9.
The Extension Identifier field shall be "AAIP_0100" with Identifier Length 9.
The mandatory content form of the Extension Descriptor is
"AA PROVIDES VIA AAIP 0.2 SUPPORT FOR ARBITRARY FILE ATTRIBUTES IN ISO 9660 IMAGES"
"AA PROVIDES VIA AAIP 1.0 SUPPORT FOR ARBITRARY FILE ATTRIBUTES IN ISO 9660 IMAGES"
The Description Length is 81.
The recommended content of the Extension Source is
@ -365,20 +361,19 @@ AAIP ER and the ES entries. But if there is the AAIP ER then there must be ES
at the appropriate places. Else the format would explicitely violate SUSP-1.12.
-------------------------------------------------------------------------------
Model Relations:
Attribute List ------------- [1:0..1] ------------- ACL
[1:0..n] [1:0..n]
Attribute List ------------- [1:0..1] ------------- ACL
[1:0..n] [1:0..n]
Arbitrary Attribute ( [1:0..1] ACL ) Entry
[1:2..2n] [1:0..1]
Component ( [1..m:1..n] AA Field ) Qualifier
[1:1..n] << one of >>
Component Record / \ \
[1..m:1..n] Translation Entry , Name , Numeric Id
AA Field | | |
[1:1..n] [1:1..n] [1:1]
\ | /
[1:1..n] << one of >>
Component Record / \
[1..m:1..n] Translation Entry , Numeric Id
AA Field | |
[1:1..n] [1:1]
\ /
Qualifier Record
-------------------------------------------------------------------------------
@ -387,9 +382,15 @@ Revoked drafts:
There was a draft AAIP 0.0 with ER signature "AAIP_2008A". It did not resemble
the existing entry SL and therefore shall not be used by writers of ISO images.
AAIP 0.2 once allowed to announce and use a different signature than "AA".
This has been revoked because ES entries serve the purpose to distinguish
AAIP entries from eventual "AA" entries of any other extension.
AAIP 0.2 with ER signature "AAIP_0002" allowed to announce and use a different
signature than "AA". This has been revoked because ES entries serve the purpose
to distinguish AAIP entries from eventual "AA" entries of any other extension.
AAIP 0.2 defined two ACL types which did not make it into AAIP 1.0
2 ACL_USER of arbitrary user, with name as qualifier
4 ACL_GROUP of arbitrary group, with name as qualifier
Their job was transferred to ACL_USER_N and ACL_GROUP_N which have numeric
qualifiers.
-------------------------------------------------------------------------------
References:
@ -402,8 +403,3 @@ RRIP 1.12 ftp://ftp.ymi.com/pub/rockridge/rrip112.ps
(especially entry SL)
-------------------------------------------------------------------------------
Pending considerations:
- shall the tag types ACL_USER and ACL_GROUP with non-numeric qualifier be
revoked ?