[gentoo-dev] Initial review: registration for text/vnd.gentoo.manifest media type

[Michał Górny]

Hi,

I'd like to give it a shot and try to register a media type for GLEP 74
Manifest files.  I've specifically chosen this type because it's
relatively simple and well-specified.  I'd like to request your feedback
on the registration form, then ask Council for approving it and then
send it to IANA media-types ml for feedback.


```
Type name: text

Subtype name: vnd.gentoo.manifest

Required parameters:

charset - always "UTF-8"


Optional parameters:

none


Encoding considerations:

8-bit text

always encoded as UTF-8, the format technically permits encoding all
Unicode characters as 7-bit escape codes


Security considerations:

The Manifest files are text files that are transmitted as part of larger
file sets in order to provide integrity and authenticity verification
for other files.  They are primarily intended to be processed locally
to verify transferred files.

The format does not provide support for executable content.  It does
provide support for specifying arbitrary filenames to verify.  Symbolic
links are followed when opening files.  The tools are explicitly
required to be secured against attempting to read non-regular files.
No other dangers were identified from the ability to verify arbitrary
file checksums locally (GLEP 74 § 3.3).

The initial Manifest file to be processed must not be compressed.
It can contain an inline OpenPGP signature to provide authenticity
verification.  Every Manifest file can reference subsequent Manifest
files to be processed.  Subsequent Manifest files can be compressed.
The tools are required to verify the integrity (and authenticity,
if provided) of subsequent Manifest files prior to decompressing them
(GLEP 74 § 3.2 / 3.12).

The Manifest files have no special privacy considerations.  The same
privacy considerations as for the files covered by the Manifest apply.


Interoperability considerations:

The format is using UTF-8 encoding for best interoperability.  Platforms
using non-UTF-8 filesystem encoding need to be able to recode filenames
to UTF-8.  The format does not provide support for using raw filenames
with unknown encoding.

The format does not specify newline encoding.  The implementations need
to be able to support different platform newline conventions for
portability.

The format specifies the use of forward slash as a directory separator.
Platforms using a different character need to convert paths
appropriately.


Published specification:

GLEP 74: Full-tree verification using Manifest files
https://www.gentoo.org/glep/glep-0074.html


Applications that use this media type:

The reference implementation for the format is provided by the gemato
tool [1].  A subset of the format is also directly supported by Gentoo
package managers, e.g. Portage [2] and pkgcore [3].  This list is not
exhaustive.

[1] https://github.com/projg2/gemato
[2] https://wiki.gentoo.org/wiki/Project:Portage
[3] https://github.com/pkgcore/pkgcore


Fragment identifier considerations:

None.


Additional information:

 Deprecated alias names for this type: none
 Magic number(s): none
 File extension(s): none, the file is commonly named "Manifest"
 Macintosh file type code(s): none

Person & email address to contact for further information:

Michał Górny <mgorny@g.o>


Intended usage: COMMON

Restrictions on usage:

None.


Author: Michał Górny <mgorny@g.o>

Change controller: Gentoo Council <council@g.o>

Provisional registration? (standards tree only): no
```

-- 
Best regards,
Michał Górny