evennia/src/locks/lockfuncs.py

318 lines
13 KiB
Python

"""
This module provides a set of permission lock functions for use
with Evennia's permissions system.
To call these locks, make sure this module is included in the
settings tuple PERMISSION_FUNC_MODULES then define a lock on the form
'<access_type>:func(args)' and add it to the object's lockhandler.
Run the check method of the handler to execute the lock check.
Note that accessing_obj and accessed_obj can be any object type
with a lock variable/field, so be careful to not expect
a certain object type.
MUX locks
Below is a list nicked from the MUX docs on the locks available
in MUX. These are not all necessarily relevant to an Evennia game
but to show they are all possible with Evennia, each entry is a
suggestion on how one could implement similar functionality in Evennia.
Name: Affects: Effect:
-------------------------------------------------------------------------
DefaultLock: Exits: controls who may traverse the exit to
its destination.
Evennia: specialized permission key
'traverse' checked in move method
Rooms: controls whether the player sees the SUCC
or FAIL message for the room following the
room description when looking at the room.
Evennia: This is better done by implementing
a clever room class ...
Players/Things: controls who may GET the object.
Evennia: specialized permission key 'get'
defined on object, checked by get command
EnterLock: Players/Things: controls who may ENTER the object
Evennia: specialized permission key 'enter'
defined on object, checked by move command
GetFromLock: All but Exits: controls who may gets things from a given
location.
Evennia: Probably done best with a lock function
that searches the database for permitted users
GiveLock: Players/Things: controls who may give the object.
Evennia: specialized permission key 'give'
checked by the give command
LeaveLock: Players/Things: controls who may LEAVE the object.
Evennia: specialized permission key 'leave'
checked by move command
LinkLock: All but Exits: controls who may link to the location if the
location is LINK_OK (for linking exits or
setting drop-tos) or ABODE (for setting
homes)
Evennia: specialized permission key 'link'
set on obj and checked by link command
MailLock: Players: controls who may @mail the player.
Evennia: Lock function that pulls the
config from the player to see if the
calling player is on the blacklist/whitelist
OpenLock: All but Exits: controls who may open an exit.
Evennia: specialized permission key 'open'
set on exit, checked by open command
PageLock: Players: controls who may page the player.
Evennia: see Maillock
ParentLock: All: controls who may make @parent links to the
object.
Evennia: This is handled with typeclasses
and typeclass switching instead.
ReceiveLock: Players/Things: controls who may give things to the object.
Evennia: See GiveLock
SpeechLock: All but Exits: controls who may speak in that location
Evennia: Lock function checking if there
is some special restrictions on the room
(game dependent)
TeloutLock: All but Exits: controls who may teleport out of the
location.
Evennia: See LeaveLock
TportLock: Rooms/Things: controls who may teleport there
Evennia: See EnterLock
UseLock: All but Exits: controls who may USE the object, GIVE the
object money and have the PAY attributes
run, have their messages heard and possibly
acted on by LISTEN and AxHEAR, and invoke
$-commands stored on the object.
Evennia: Implemented per game
DropLock: All but rooms: controls who may drop that object.
Evennia: specialized permission key 'drop'
set on room, checked by drop command.
VisibleLock: All: Controls object visibility when the object
is not dark and the looker passes the lock.
In DARK locations, the object must also be
set LIGHT and the viewer must pass the
VisibleLock.
Evennia: Better done with Scripts implementing
a dark state/cmdset. For a single object,
use a specialized permission key 'visible'
set on object and checked by look command.
"""
from django.conf import settings
from src.utils import search
PERMISSION_HIERARCHY = [p.lower() for p in settings.PERMISSION_HIERARCHY]
def true(*args, **kwargs):
"Always returns True."
return True
def all(*args, **kwargs):
return True
def false(*args, **kwargs):
"Always returns False"
return False
def none(*args, **kwargs):
return False
def perm(accessing_obj, accessed_obj, *args, **kwargs):
"""
The basic permission-checker. Ignores case.
Usage:
perm(<permission>)
where <permission> is the permission accessing_obj must
have in order to pass the lock. If the given permission
is part of PERMISSION_HIERARCHY, permission is also granted
to all ranks higher up in the hierarchy.
"""
if not args:
return False
perm = args[0].lower()
if hasattr(accessing_obj, 'permissions'):
if perm in [p.lower() for p in accessing_obj.permissions]:
# simplest case - we have a direct match
return True
if perm in PERMISSION_HIERARCHY:
# check if we have a higher hierarchy position
ppos = PERMISSION_HIERARCHY.index(perm)
return any(True for hpos, hperm in enumerate(PERMISSION_HIERARCHY)
if hperm in [p.lower() for p in accessing_obj.permissions] and hpos > ppos)
return False
def perm_above(accessing_obj, accessed_obj, *args, **kwargs):
"""
Only allow objects with a permission *higher* in the permission
hierarchy than the one given. If there is no such higher rank,
it's assumed we refer to superuser. If no hierarchy is defined,
this function has no meaning and returns False.
"""
if args and args[0].lower() in PERMISSION_HIERARCHY:
ppos = PERMISSION_HIERARCHY.index(args[0].lower())
return any(True for hpos, hperm in enumerate(PERMISSION_HIERARCHY)
if hperm in [p.lower() for p in accessing_obj.permissions] and hpos > ppos)
def dbref(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
dbref(3)
This lock type checks if the checking object
has a particular dbref. Note that this only
works for checking objects that are stored
in the database (e.g. not for commands)
"""
if not args:
return False
try:
dbref = int(args[0].strip().strip('#'))
except ValueError:
return False
if hasattr(accessing_obj, 'id'):
return dbref == accessing_obj.id
return False
def id(accessing_obj, accessed_obj, *args, **kwargs):
"Alias to dbref"
return dbref(accessing_obj, accessed_obj, *args, **kwargs)
def attr(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
has_attr(attrname)
has_attr(attrname, value)
has_attr(attrname, value, compare=type)
where compare's type is one of (eq,gt,lt,ge,le,ne) and signifies
how the value should be compared with one on accessing_obj (so
compare=gt means the accessing_obj must have a value greater than
the one given).
Searches attributes *and* properties stored on the checking
object. The first form works like a flag - if the attribute/property
exists on the object, it returns True. The second form also requires
that the value of the attribute/property matches. Note that all
retrieved values will be converted to strings before doing the comparison.
"""
# deal with arguments
if not args:
return False
attrname = args[0].strip()
value = None
if len(args) > 1:
value = args[1].strip()
compare = 'eq'
if kwargs:
compare = kwargs.get('compare', 'eq')
def valcompare(val1, val2, typ='eq'):
"compare based on type"
try:
if typ == 'eq':
return val1 == val2 or int(val1) == int(val2)
elif typ == 'gt':
return int(val1) > int(val2)
elif typ == 'lt':
return int(val1) < int(val2)
elif typ == 'ge':
return int(val1) >= int(val2)
elif typ == 'le':
return int(val1) <= int(val2)
elif typ == 'ne':
return int(val1) != int(val2)
else:
return False
except Exception, e:
print e
# this might happen if we try to compare two things that cannot be compared
return False
# first, look for normal properties on the object trying to gain access
if hasattr(accessing_obj, attrname):
if value:
return valcompare(str(getattr(accessing_obj, attrname)), value, compare)
return True
# check attributes, if they exist
if (hasattr(accessing_obj, 'has_attribute')
and accessing_obj.has_attribute(attrname)):
if value:
return (hasattr(accessing_obj, 'get_attribute')
and valcompare(accessing_obj.get_attribute(attrname), value, compare))
return True
return False
def attr_eq(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
"""
return attr(accessing_obj, accessed_obj, *args, **kwargs)
def attr_gt(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
Only true if access_obj's attribute > the value given.
"""
return attr(accessing_obj, accessed_obj, *args, **{'compare':'gt'})
def attr_ge(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
Only true if access_obj's attribute >= the value given.
"""
return attr(accessing_obj, accessed_obj, *args, **{'compare':'ge'})
def attr_lt(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
Only true if access_obj's attribute < the value given.
"""
return attr(accessing_obj, accessed_obj, *args, **{'compare':'lt'})
def attr_le(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
Only true if access_obj's attribute <= the value given.
"""
return attr(accessing_obj, accessed_obj, *args, **{'compare':'le'})
def attr_ne(accessing_obj, accessed_obj, *args, **kwargs):
"""
Usage:
attr_gt(attrname, 54)
Only true if access_obj's attribute != the value given.
"""
return attr(accessing_obj, accessed_obj, *args, **{'compare':'ne'})
def holds(accessing_obj, accessed_obj, objid, *args, **kwargs):
"""
Usage:
holds(object_id)
This is passed if accessing_obj 'contains' an object with the given
key name or dbref.
"""
dbref = utils.dbref(objid)
contains = accessing_obj.contains
if dbref and any((True for obj in contains if obj.id == dbref)):
return True
objid = objid.lower()
return any((True for obj in contains if obj.name.lower() == objid))
def superuser(*args, **kwargs):
"""
Only accepts an accesing_obj that is superuser (e.g. user #1)
Since a superuser would not ever reach this check (superusers
bypass the lock entirely), any user who gets this far cannot be a
superuser, hence we just return False. :)
"""
return False