util/rights.py

   1 # rights.py
   2 #
   3 # support for privileges according to GENI specification
   4
   5 # privilege_table:
   6 #
   7 # a list of priviliges and what operations are allowed per privilege
   8
   9 privilege_table = {"authority": ["*"],
  10                    "refresh": ["remove", "update"],
  11                    "resolve": ["resolve", "list", "getcredential"],
  12                    "sa": ["*"],
  13                    "embed": ["getticket", "createslice", "deleteslice", "updateslice"],
  14                    "bind": ["getticket", "loanresources"],
  15                    "control": ["updateslice", "stopslice", "startslice", "deleteslice"],
  16                    "info": ["listslices", "listcomponentresources", "getsliceresources"],
  17                    "ma": ["*"]}
  18
  19 # a "Right" is a single privilege.
  20
  21 class Right:
  22    def __init__(self, kind):
  23       self.kind = kind
  24
  25    def can_perform(self, op_name):
  26       allowed_ops = privilege_table.get(self.kind.lower(), None)
  27       if not allowed_ops:
  28          return False
  29
  30       # if "*" is specified, then all ops are permitted
  31       if "*" in allowed_ops:
  32          return True
  33
  34       return (op_name.lower() in allowed_ops)
  35
  36 # a "RightList" is a list of privileges
  37
  38 class RightList:
  39     def __init__(self, string=None):
  40         self.rights = []
  41         if string:
  42             self.load_from_string(string)
  43
  44     def load_from_string(self, string):
  45         self.rights = []
  46
  47         # none == no rights, so leave the list empty
  48         if not string:
  49             return
  50
  51         parts = string.split(",")
  52         for part in parts:
  53             self.rights.append(Right(part))
  54
  55     def save_to_string(self):
  56         right_names = []
  57         for right in self.rights:
  58             right_names.append(right.kind)
  59
  60         return ",".join(right_names)
  61
  62     def can_perform(self, op_name):
  63         for right in self.rights:
  64             if right.can_perform(op_name):
  65                 return True
  66         return False
  67
  68