The proposal here is to specify a naming scheme for permissions
that allows the system to be as stateless as possible. The current
-current specification includes in the naming of permissions either
+specification includes in the naming of permissions either
the name of the bound binding when existing and the level of the
permission itself. Doing this, there is no real need for the
-framework to keep updated a database of installed permissions.
+framework to keep installed permissions in a database.
The permission names are [URN][URN] of the form:
- urn:AGL:permission:<binding>:<level>:<hierarchical-name>
+ urn:AGL:permission:<api>:<level>:<hierarchical-name>
where "AGL" is the NID (the namespace identifier) dedicated to
AGL (note: a RFC should be produced to standardize this name space).
The permission names are made of NSS (the namespace specific string)
starting with "permission:" and followed by colon separated
-fields. The 2 first fields are <binding> and <level> and the remaining
-fields are gouped to form the <hierarchical-name>.
+fields. The 2 first fields are `<api>` and `<level>` and the remaining
+fields are grouped to form the `<hierarchical-name>`.
+
+ <api> ::= [ <pname> ]
- <binding> ::= [ <pname> ]
-
<pname> ::= 1*<pchars>
-
+
<pchars> ::= <upper> | <lower> | <number> | <extra>
-
+
<extra> ::= "-" | "." | "_" | "@"
-The field <binding> can be made of any valid character for NSS except
-the characters colon and star (:*). This field designate the binding
-providing the permission. It is use to deduce binding requirements
-from permission requirements. The field <binding> can be the empty
+The field `<api>` can be made of any valid character for NSS except
+the characters colon and star (:*). This field designates the api
+providing the permission. This scheme is used to deduce binding requirements
+from permission requirements. The field `<api>` can be the empty
string when the permission is defined by the AGL system itself.
-The field <binding> if starting with the character "@" represents
-a transversal permission not bound to any binding.
+
+[PROPOSAL 1] The field `<api>` if starting with the character "@" represents
+a transversal/cross permission not bound to any binding.
+
+[PROPOSAL 2]The field `<api>` if starting with the 2 characters "@@"
+in addition to a permission not bound to any binding, represents a
+permission that must be set at installation and that can not be
+revoked later.
<level> ::= 1*<lower>
-The field <level> is made only of letters in lower case.
-The field <level> can only take some predefined values:
-"system", "platform", "partner", "tiers", "owner", "public".
+The field `<level>` is made only of letters in lower case.
+The field `<level>` can only take some predefined values:
+
+ - system
+ - platform
+ - partner
+ - tiers
+ - owner
+ - public
+
+The field `<hierarchical-name>` is made of `<pname>` separated
+by colons.
<hierarchical-name> ::= <pname> 0*(":" <pname>)
-The field <hierarchical-name> is made <pname> separated by
-colons. The names at left are hierarchically grouping the
+The names at left are hierarchically grouping the
names at right. This hierarchical behaviour is intended to
be used to request permissions using hierarchical grouping.
-Permission's level
-------------------
+
+Permission value
+----------------
+
+In some case, it could be worth to add a value to a permission.
+
+Currently, the framework allows it for permissions linked to
+systemd. But this not currently used.
+
+Conversely, permissions linked to cynara can't carry data
+except in their name.
+
+Thus to have a simple and cleaner model, it is better to forbid
+attachement of value to permission.
+
+
+Example of permissions
+----------------------
+
+Here is a list of some possible permissions. These
+permissions are available the 17th of March 2017.
+
+ - urn:AGL:permission::platform:no-oom
+
+ Set OOMScoreAdjust=-500 to keep the out-of-memory
+ killer away.
+
+ - urn:AGL:permission::partner:real-time
+
+ Set IOSchedulingClass=realtime to give to the process
+ realtime scheduling.
+
+ Conversely, not having this permission set RestrictRealtime=on
+ to forbid realtime features.
+
+ - urn:AGL:permission::public:display
+
+ Adds the group "display" to the list of supplementary groups
+ of the process.
+
+ - urn:AGL:permission::public:syscall:clock
+
+ Without this permission SystemCallFilter=~@clock is set to
+ forfid call to clock.
+
+ - urn:AGL:permission::public:no-htdocs
+
+ The http directory served is not "htdocs" but "."
+
+ - urn:AGL:permission::public:applications:read
+
+ Allows to read data of installed applications (and to
+ access icons).
+
+ - urn:AGL:permission::partner:service:no-ws
+
+ Forbids services to provide its API through websocket.
+
+ - urn:AGL:permission::partner:service:no-dbus
+
+ Forbids services to provide its API through D-Bus.
+
+ - urn:AGL:permission::system:run-by-default
+
+ Starts automatically the application. Example: home-screen.
+
+ - http://tizen.org/privilege/internal/dbus
+
+ Permission to use D-Bus.
[URN]: https://tools.ietf.org/rfc/rfc2141.txt "RFC 2141: URN Syntax"
Code Review / src / app-framework-main.git / blobdiff