/* * Copyright (c) 2000-2004,2006 Apple Computer, Inc. All Rights Reserved. * * @APPLE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this * file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_LICENSE_HEADER_END@ */ // // acl_threshold - Threshold-based group ACL subjects. // // This subject type implements threshold (k of n) subjects as per CSSM standard. // Subsubjects are stored and evaluated in the order received. Any subsubject // is presented with all subsamples of the corresponding threshold sample, but // not any other samples possibly present in the credentials. Subsubject evaluation // stops as soon as the threshold is satisfied, or as soon as it becomes numerically // impossible to satisfy the threshold with future matches. // Note that this subject will reject out of hand any threshold sample that // contains more than <n> subsamples. This defeats "sample stuffing" attacks // where the attacker provides thousands of samples in the hope that some may // match by accident. It will however accept threshold samples with fewer than // <n> subsamples, as long as there are at least <k> subsamples. // #ifndef _ACL_THRESHOLD #define _ACL_THRESHOLD #include <security_cdsa_utilities/cssmacl.h> #include <vector> namespace Security { class ThresholdAclSubject : public SimpleAclSubject { typedef ObjectAcl::AclSubjectPointer AclSubjectPointer; typedef vector<AclSubjectPointer> AclSubjectVector; public: bool validate(const AclValidationContext &baseCtx, const TypedList &sample) const; CssmList toList(Allocator &alloc) const; ThresholdAclSubject(uint32 n, uint32 k, const AclSubjectVector &subSubjects); void exportBlob(Writer::Counter &pub, Writer::Counter &priv); void exportBlob(Writer &pub, Writer &priv); unsigned count() const { return totalSubjects; } AclSubject *subject(unsigned n) const { return elements[n]; } void add(AclSubject *subject, unsigned beforePosition); IFDUMP(void debugDump() const); class Maker : public AclSubject::Maker { public: Maker() : AclSubject::Maker(CSSM_ACL_SUBJECT_TYPE_THRESHOLD) { } ThresholdAclSubject *make(const TypedList &list) const; ThresholdAclSubject *make(Version, Reader &pub, Reader &priv) const; }; private: uint32 minimumNeeded; // number of matches needed uint32 totalSubjects; // number of subSubjects AclSubjectVector elements; // sub-subject vector template <class Action> void exportBlobForm(Action &pub, Action &priv); }; } // namespace Security #endif //_ACL_THRESHOLD