su4sml/src/secure_uml.sml

411 lines
17 KiB
Standard ML

(*****************************************************************************
* su4sml --- an SML repository for managing (Secure)UML/OCL models
* http://projects.brucker.ch/su4sml/
*
* secure_uml.sml --- a security language implementing mds.sig
* This file is part of su4sml.
*
* Copyright (c) 2005-2007, ETH Zurich, Switzerland
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* * Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
******************************************************************************)
(* $Id$ *)
(**
* SecureUML is a simple security language based on RBAC.
* Permissions relate roles with actions and can be further constrained
* using OCL:
*)
signature SECUREUML =
sig
include SECURITY_LANGUAGE
type Role
type Subject
val all_roles : Configuration -> Role list
val all_constraints: Configuration -> Rep_OclTerm.OclTerm list
val all_subjects: Configuration -> Subject list
val constraints_of : Permission -> Rep_OclTerm.OclTerm list
val roles_of: Permission -> Role list
val subject_name_of: Subject -> string
val subject_roles_of:Subject -> Configuration -> Role list
end
(**
* SecureUML is a simple security language based on RBAC.
* Permissions relate roles with actions and can be further constrained
* using OCL:
*)
functor SecureUML(structure Design: DESIGN_LANGUAGE):SECUREUML =
struct
open Rep_Helper
structure Design : DESIGN_LANGUAGE = Design
type User = string
fun name_of (u:User) = u
datatype Subject = Group of string * (string list)
| User of User
fun subject_name_of (Group (g,_)) = g
| subject_name_of (User u) = u
type Role = string
type SubjectAssignment = (Subject * (Role list)) list
type Permission = {name: string,
roles: Role list,
constraints: Rep_OclTerm.OclTerm list,
actions: Design.Action list }
type Config_Type = string
type 'a partial_order = ('a * 'a) list
type Configuration = { config_type: Config_Type,
permissions: Permission list,
subjects: Subject list,
(* groups: Group partial_order,*)
roles: Role list,
rh: Role partial_order,
sa: SubjectAssignment }
fun subject_roles_of (s:Subject) (c:Configuration) =
(snd o valOf o (List.find (fn x => (fst x) = s)) o #sa) c
fun constraints_of (x:Permission) = #constraints x
fun roles_of (x:Permission) = #roles x
fun actions_of (p:Permission) = #actions p
fun all_roles (c:Configuration) = #roles c
fun all_subjects (c:Configuration)= #subjects c
fun all_constraints (c:Configuration) = List.concat (List.map constraints_of (#permissions c))
(** test whether a1 is (transitively) a subordinated_action of a2 *)
fun is_contained_in a1 a2 = (a1 = a2) orelse
List.exists (is_contained_in a1)
(Design.subordinated_actions a2)
(** test whether the permission p covers the action a. *)
fun permission_includes_action (p:Permission) (a:Design.Action) =
List.exists (is_contained_in a) (#actions p)
(* unclear yet how this will look like:
fun domain_of (x:'a partial_order) = ...
fun closure_of (x:'a partial_order) = ...
*)
fun type_of (c:Configuration) = #config_type c
fun is_empty (c:Configuration) = List.null (#permissions c) andalso
List.null (#subjects c)
fun getPermissions (c:Configuration) = #permissions c
(* the following functions have yet to be implemented *)
fun users_of p = nil
fun check_permission (u,p) = false
fun permissions_of u = nil
(** checks whether the classifier c has the stereotype s.
* (could be moved to rep_core?)
*)
fun classifier_has_stereotype s c = ListEq.includes (Rep.stereotypes_of c) s
(** checks whether the classifier c has none of the given stereotypes *)
fun classifier_has_no_stereotype strings c =
ListEq.disjunct strings (Rep.stereotypes_of c)
(** checks whether the classifier c has a parent.
* (could be moved to rep_core?)
*)
fun classifier_has_parent (Rep.Class c) = Option.isSome (#parent c)
| classifier_has_parent (Rep.AssociationClass c) = Option.isSome (#parent c)
| classifier_has_parent (Rep.Interface c) = not (List.null (#parents c))
| classifier_has_parent (Rep.Enumeration c) = Option.isSome (#parent c)
| classifier_has_parent (Rep.Primitive c) = Option.isSome (#parent c)
| classifier_has_parent (Rep.Template c) = classifier_has_parent (#classifier c)
fun filter_permission cs = List.filter (classifier_has_stereotype
"secuml.permission") cs
(* FIXME: handle groups also *)
fun filter_subject cs = List.filter (classifier_has_stereotype "secuml.user") cs
fun filter_role cs = List.filter (classifier_has_stereotype "secuml.role") cs
fun mkRole (C as Rep.Class c) = Rep.string_of_path (Rep.name_of C)
| mkRole _ = Logger.error ("in mkRole: argument is not a class")
(* FIXME: handle groups also *)
fun mkSubject (C as Rep.Class c) = User (Rep.string_of_path (Rep.name_of C))
| mkSubject _ = Logger.error ("in mkSubject: argument is not a class")
fun mkPermission (cs,ascs) (c as Rep.Class _) =
let val classifiers = (Rep.connected_classifiers_of ascs c cs)
val role_classes = List.filter (classifier_has_stereotype "secuml.role")
classifiers
val root_classes = List.filter (fn x => ListEq.overlaps
(Rep.stereotypes_of x)
Design.root_stereotypes)
classifiers
val root_resource = hd root_classes
handle Empty => Logger.error ("in mkPermission: no root resource found "^
"for permission "^Rep.string_of_path (Rep.name_of c))
val action_attributes =
List.filter (fn x => ListEq.overlaps (#stereotypes x) (Design.action_stereotypes))
(Rep.attributes_of c)
handle ex => (Logger.error "could not parse permission attributes"; raise ex)
in
{ name = (Rep.string_of_path (Rep.name_of c)),
roles = (map (Rep.string_of_path o Rep.name_of) role_classes),
(* FIXME: find attached constraints *)
constraints = nil,
actions = if action_attributes = []
then Logger.error ("in mkPermission: Permission "^
(Rep.string_of_path (Rep.name_of c))^
"has no action attributes")
else map (Design.parse_action root_resource) action_attributes }
end
| mkPermission _ _ = Logger.error "in mkPermission: argument is not a class"
fun mkSubjectAssignment (cs,ascs) (c as (Rep.Class _)) =
let (* FIXME: we just take all roles that are connected to the subject. *)
(* in principle, we should check the stereotype of the association, *)
(* but that does not exist in the rep datastructure... *)
val classifiers = List.filter (classifier_has_stereotype "secuml.role")
(Rep.connected_classifiers_of ascs c cs)
in
(mkSubject c, map mkRole classifiers)
end
(*
fun update_aends (Rep.Class { name, parent,attributes,operations,associations,
invariant, stereotypes,interfaces,thyname,activity_graphs}) aends =
let
(*
*)
fun assoc_of_aend ({name,...}:Rep_Core.associationend) = List.take (name,List.length name -1 )
val assocs = map assoc_of_aend aends
fun is_member ({name,...}:Rep_Core.association) = List.exists (fn x => x=name) assocs
in
Rep.Class {name=name, parent=parent, attributes=attributes,
operations=operations(*, associations=map assoc_of_aend aends*),
associations = filter is_member associations,
invariant=invariant, stereotypes=stereotypes,
interfaces=interfaces, thyname=thyname,
activity_graphs=activity_graphs}
end
| update_aends (Rep.AssociationClass { name, parent,attributes,operations,associations,association,
invariant, stereotypes,interfaces,thyname,activity_graphs}) aends =
let
fun assoc_of_aend ({name,...}:Rep_Core.associationend) = List.take (name,List.length name -1 )
val assocs = map assoc_of_aend aends
fun is_member ({name,...}:Rep_Core.association) = List.exists (fn x => x=name) assocs
in
Rep.AssociationClass {name=name, parent=parent, attributes=attributes,
operations=operations(*, associations=map assoc_of_aend aends*),
associations = filter is_member associations,
association = association (* FIXME: proper handling? *),
invariant=invariant, stereotypes=stereotypes,
interfaces=interfaces, thyname=thyname,
activity_graphs=activity_graphs}
end
*)
fun update_assocs (Rep.Class { name, parent,attributes,operations,associations,
invariant,stereotypes,interfaces,thyname,visibility,activity_graphs}) assocs =
Rep.Class {name=name, parent=parent, attributes=attributes,
operations=operations, associations=assocs,
invariant=invariant, stereotypes=stereotypes,
interfaces=interfaces, thyname=thyname,
visibility=visibility,
activity_graphs=activity_graphs}
| update_assocs (Rep.AssociationClass { name, parent,attributes,operations,associations,association,
invariant, stereotypes,interfaces,thyname,visibility,activity_graphs}) assocs =
Rep.AssociationClass {name=name, parent=parent, attributes=attributes,
operations=operations, associations=assocs,association=association,
invariant=invariant, stereotypes=stereotypes,visibility=visibility,
interfaces=interfaces, thyname=thyname,
activity_graphs=activity_graphs}
fun assocConnectsToSecureUml cs (a:Rep.associationend) =
classifier_has_no_stereotype ["secuml.permission",
"secuml.role",
"secuml.user"]
(Rep.class_of (Rep_OclType.path_of_OclType (#aend_type a)) cs)
(** remove aends from classifiers to permissions and roles.
* Actual generation of permissions and roles is done in parse below.
*)
fun removeSecureUmlAends (Rep.Class {name=class_name,...},(assocs,removed_assocs)):(Rep.association list * Rep.association list) =
let
fun remove_aend ({name,aclass,qualifiers,aends}:Rep.association):
Rep.association =
{name = name,
aclass = aclass,
qualifiers=qualifiers,
aends = filter (fn {aend_type,...} => not (aend_type = class_name))
aends
}
fun non_emtpy ({aends,...}:Rep.association) = List.length aends >= 2 (* FIXME: reflexive association -> 2 aends? *)
val reduced_assocs = map remove_aend assocs
val (modified_assocs,newly_removed_assocs) = List.partition non_emtpy reduced_assocs
in
(modified_assocs,newly_removed_assocs @ removed_assocs)
end
| removeSecureUmlAends (Rep.AssociationClass {name=class_name,...},
(assocs,removed_assocs)):
(Rep.association list * Rep.association list) =
let
fun remove_aend ({name,aclass,qualifiers,aends}:Rep.association):
Rep.association =
{name = name,
aclass = aclass,
qualifiers=qualifiers,
aends = filter (fn {aend_type,...} => not (aend_type = class_name))
aends
}
fun non_emtpy ({aends,...}:Rep.association) = List.length aends >= 2 (* FIXME: reflexive association -> 2 aends? *)
val reduced_assocs = map remove_aend assocs
val (modified_assocs,newly_removed_assocs) = List.partition non_emtpy reduced_assocs
(* FIXME: proper handling for aclass? *)
in
(modified_assocs,newly_removed_assocs @ removed_assocs)
end
(** parse a list of classifiers according to the SecureUML profile.
* removes the classes with SecureUML stereotypes.
*)
fun parse (model as (cs,assocs):Rep.Model) =
let val _ = Logger.info "parsing security configuration"
val non_secureumlstereotypes = List.filter (classifier_has_no_stereotype ["secuml.permission",
"secuml.role",
"secuml.subject",
"secuml.actiontype"]) cs
val secureumlstereotypes = List.filter (classifier_has_no_stereotype ["secuml.permission",
"secuml.role",
"secuml.user"]) cs
(* remove classes with SecureUML stereotypes from the association list
* and update affected classes if the association ceases to exist
*)
fun updateClassifierAssociations rem_assocs (Rep.Class {name, parent, attributes, operations,
associations, invariant, stereotypes,
interfaces, thyname,visibility,activity_graphs}) =
let
val assoc_names = map (fn {name,aends,qualifiers,aclass} => name)
rem_assocs
fun non_emtpy path = not (List.exists (fn aname => aname = path)
assoc_names)
in
Rep.Class {name = name,
parent = parent,
attributes = attributes,
operations = operations,
associations = filter non_emtpy associations,
invariant = invariant,
stereotypes = stereotypes,
interfaces = interfaces,
thyname = thyname,
visibility = visibility,
activity_graphs = activity_graphs}
end
| updateClassifierAssociations rem_assocs (Rep.AssociationClass {name, parent, attributes,
operations, associations,
association, invariant,visibility,
stereotypes, interfaces,
thyname, activity_graphs}) =
let
val assoc_names = map (fn {name,aends,qualifiers,aclass} => name)
rem_assocs
fun non_emtpy path = not (List.exists (fn aname => aname = path)
assoc_names)
in
Rep.AssociationClass {name = name,
parent = parent,
attributes = attributes,
operations = operations,
associations = filter non_emtpy associations,
association = association (* FIXME: proper handling? *),
invariant = invariant,
stereotypes = stereotypes,
interfaces = interfaces,
visibility = visibility,
thyname = thyname,
activity_graphs = activity_graphs
}
end
val (modified_assocs,removed_assocs) =
(case secureumlstereotypes of
[] => (assocs,[])
| xs => foldl removeSecureUmlAends (assocs,[]) xs)
val modified_classifiers =
(case removed_assocs of
[] => non_secureumlstereotypes
| xs => map (updateClassifierAssociations xs) non_secureumlstereotypes)
in
(
(* map (removeSecureUmlAends cs)
(List.filter (classifier_has_no_stereotype ["secuml.permission",
"secuml.role",
"secuml.subject",
"secuml.actiontype"])
cs),
*) (modified_classifiers,modified_assocs),
{ config_type = "SecureUML",
permissions = map (mkPermission model) (filter_permission cs),
subjects = map mkSubject (filter_subject cs),
roles = map mkRole (filter_role cs),
rh = map (fn x => (Rep.string_of_path (Rep.name_of x),
Rep.string_of_path (Rep.parent_name_of x)))
(List.filter classifier_has_parent (filter_role cs)),
sa = map (mkSubjectAssignment model) (filter_subject cs)})
end
handle ex => (Logger.warn "in SecureUML.parse: security configuration \
\could not be parsed";
raise ex)
end