--- /dev/null
+/*
+ * Copyright (c) 2000-2004,2006,2011,2013-2014 Apple 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@
+ */
+
+
+//
+// aclsubject - abstract ACL subject implementation
+//
+#ifndef _ACLSUBJECT
+#define _ACLSUBJECT
+
+#include <security_cdsa_utilities/cssmaclpod.h>
+#include <security_cdsa_utilities/cssmcred.h>
+#include <security_utilities/refcount.h>
+#include <security_utilities/globalizer.h>
+#include <security_utilities/memutils.h>
+#include <security_utilities/adornments.h>
+#include <map>
+#include <set>
+#include <string>
+#include <limits.h>
+
+
+namespace Security {
+
+class ObjectAcl;
+class AclValidationContext;
+class AclSubject;
+
+
+//
+// An AclValidationEnvironment can be subclassed to add context access to ACL subject
+// validation. If you use ACL subject classes that need context beyond the credential
+// structure itself, add that context to (a virtual subclass of) AclValidationContext, pass that
+// to ObjectAcl::validate() along with the credentials, and have the Subject implementation
+// access validationContext.environment().
+//
+class AclValidationEnvironment {
+ friend class AclValidationContext;
+public:
+ virtual ~AclValidationEnvironment(); // ensure virtual methods (need dynamic_cast)
+
+ // provide an Adornable for a given subject to store data in, or throw if none available (default)
+ virtual Adornable &store(const AclSubject *subject);
+};
+
+
+//
+// An AclValidationContext holds all context for an ACL evaluation in one
+// package. It's designed to provide a uniform representation of credentials, plus
+// any (trusted path and/or implicit) context information useful for ACL validation.
+//
+// Contexts are immutable (constant) for validators; they do not change at all
+// during a validation exercise. Anything that should be mutable must go into
+// the environment (which is indirect and modifyable).
+//
+class AclValidationContext {
+ friend class ObjectAcl;
+public:
+ AclValidationContext(const AccessCredentials *cred,
+ AclAuthorization auth, AclValidationEnvironment *env = NULL)
+ : mAcl((ObjectAcl*) 0xDEADDEADDEADDEAD), mSubject((AclSubject*) 0xDEADDEADDEADDEAD), mCred(cred),
+ mAuth(auth), mEnv(env), mEntryTag(NULL) { }
+ AclValidationContext(const AclValidationContext &ctx)
+ : mAcl(ctx.mAcl), mSubject(ctx.mSubject), mCred(ctx.mCred),
+ mAuth(ctx.mAuth), mEnv(ctx.mEnv), mEntryTag(NULL) { }
+ virtual ~AclValidationContext();
+
+ // access to (suitably focused) sample set
+ virtual uint32 count() const = 0; // number of samples
+ uint32 size() const { return count(); } // alias
+ virtual const TypedList &sample(uint32 n) const = 0; // retrieve one sample
+ const TypedList &operator [] (uint32 n) const { return sample(n); }
+
+ // context access
+ AclAuthorization authorization() const { return mAuth; }
+ const AccessCredentials *cred() const { return mCred; }
+ AclValidationEnvironment *environment() const { return mEnv; }
+ template <class Env> Env *environment() const { return dynamic_cast<Env *>(mEnv); }
+ AclSubject *subject() const { return mSubject; }
+ ObjectAcl *acl() const { return mAcl; }
+
+ // tag manipulation
+ virtual const char *credTag() const;
+ virtual const char *entryTag() const;
+ std::string s_credTag() const;
+ void entryTag(const char *tag);
+ void entryTag(const std::string &tag);
+
+ // selective match support - not currently implemented
+ virtual void matched(const TypedList *match) const = 0;
+ void matched(const TypedList &match) const { return matched(&match); }
+
+private:
+ void init(ObjectAcl *acl, AclSubject *subject);
+
+private:
+ ObjectAcl *mAcl; // underlying ObjectAcl
+ AclSubject *mSubject; // subject being validated
+ const AccessCredentials *mCred; // original credentials
+ AclAuthorization mAuth; // action requested
+ AclValidationEnvironment *mEnv; // environmental context (if any)
+ const char *mEntryTag; // entry tag
+};
+
+
+//
+// The AclSubject class models an ACL "subject" object. If you have a new ACL
+// subject type or variant, you make a subclass of this (plus a suitable Maker).
+//
+// Note that AclSubjects can contain both configuration and state information.
+// Configuration is set during AclSubject creation (passwords to check against,
+// evaluation options, etc.) and are typically passed on in the externalized form;
+// it is persistent.
+// On the other hand, state is volatile and is lost when the AclSubject dies.
+// This is stuff that accumulates during a particular lifetime, such as results
+// of previous evaluations (for caching or more nefarious purposes).
+// Be clear what each of your subclass members are, and document accordingly.
+//
+class AclSubject : public RefCount {
+public:
+ typedef LowLevelMemoryUtilities::Writer Writer;
+ typedef LowLevelMemoryUtilities::Reader Reader;
+
+ typedef uint8 Version; // binary version marker
+ static const int versionShift = 24; // highest-order byte of type is version
+ static const uint32 versionMask = 0xff000000;
+
+public:
+ explicit AclSubject(uint32 type, Version v = 0);
+ virtual ~AclSubject();
+ CSSM_ACL_SUBJECT_TYPE type() const { return mType; }
+
+ // validation (evaluation) primitive
+ virtual bool validate(const AclValidationContext &ctx) const = 0;
+
+ // export to CSSM interface
+ virtual CssmList toList(Allocator &alloc) const = 0;
+
+ // export/import for save/restore interface
+ virtual void exportBlob(Writer::Counter &pub, Writer::Counter &priv);
+ virtual void exportBlob(Writer &pub, Writer &priv);
+ virtual void importBlob(Reader &pub, Reader &priv);
+
+ // binary compatibility version management. The version defaults to zero
+ Version version() const { return mVersion; }
+
+ // forget any validation-related state you have acquired
+ virtual void reset();
+
+ // debug suupport (dummied out but present for -UDEBUGDUMP)
+ virtual void debugDump() const;
+ IFDUMP(void dump(const char *title) const);
+
+protected:
+ void version(Version v) { mVersion = v; }
+
+private:
+ CSSM_ACL_SUBJECT_TYPE mType;
+ Version mVersion;
+
+public:
+ class Maker {
+ public:
+ Maker(CSSM_ACL_SUBJECT_TYPE type);
+ virtual ~Maker();
+
+ uint32 type() const { return mType; }
+ virtual AclSubject *make(const TypedList &list) const = 0;
+ virtual AclSubject *make(Version version, Reader &pub, Reader &priv) const = 0;
+
+ protected:
+ // list parsing helpers
+ static void crack(const CssmList &list, uint32 count,
+ ListElement **array = NULL, ...);
+ static CSSM_WORDID_TYPE getWord(const ListElement &list,
+ int min = 0, int max = INT_MAX);
+
+ private:
+ CSSM_ACL_SUBJECT_TYPE mType;
+ };
+};
+
+
+//
+// A SimpleAclSubject validates a credential by scanning its samples
+// one at a time, without any interactions between them. Thus its validate()
+// can be a lot simpler.
+// Note that this layer assumes that subject and sample types have the same
+// value, as is typical when both are derived from a WORDID.
+//
+class SimpleAclSubject : public AclSubject {
+public:
+ SimpleAclSubject(CSSM_ACL_SUBJECT_TYPE type) : AclSubject(type) { }
+
+ bool validate(const AclValidationContext &ctx) const;
+ virtual bool validate(const AclValidationContext &baseCtx,
+ const TypedList &sample) const = 0;
+};
+
+
+} // end namespace Security
+
+
+#endif //_ACLSUBJECT
projects / apple / security.git / blobdiff