1/* 2 * Copyright (c) 2000-2004 Apple Computer, Inc. All Rights Reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24 25// 26// context - manage CSSM (cryptographic) contexts every which way 27// 28#ifndef _H_CSSMCONTEXT 29#define _H_CSSMCONTEXT 30 31#include "cssmint.h" 32#include "cspattachment.h" 33#include <security_cdsa_utilities/context.h> 34 35#ifdef _CPP_CSSMCONTEXT 36# pragma export on 37#endif 38 39 40// 41// A HandleContext adds handle semantics to the Context object. 42// Note that not every Context is a HandleContext - the Contexts we hand 43// to our API customers for fondling are not. Also note that a HandleContext 44// not a PODWrapper. 45// HandleContext has an allocation method taking a Allocator. To destroy 46// a HandleObject, call HandleObject::destroy(the-context, the-allocator). 47// You are responsible for picking the same allocator used on construction. 48// 49// THREADS: HandleContexts are assumed to have single-thread use. That means that 50// operations on HandleContexts are NOT interlocked automatically; two users of 51// the same context must do any arbitration themselves. A HandleContext is howerver 52// safely interlocked against other objects, in particular its CSPAttachment. 53// The upshot is that you're safe using a HandleContext unless someone else is trying 54// to use the same context in parallel. 55// 56class HandleContext : public HandleObject, public Context { 57public: 58 HandleContext(CSPAttachment &attach, 59 CSSM_CONTEXT_TYPE type, 60 CSSM_ALGORITHMS algorithmId) 61 : Context(type, algorithmId), attachment(attach), extent(0) { } 62 virtual ~HandleContext(); 63 64 CSPAttachment &attachment; 65 66 using Context::find; // guard against HandleObjec::find 67 68 void mergeAttributes(const CSSM_CONTEXT_ATTRIBUTE *attributes, uint32 count); 69 CSSM_RETURN validateChange(CSSM_CONTEXT_EVENT event); 70 71 void *operator new (size_t size, Allocator &alloc) throw(std::bad_alloc) 72 { return alloc.malloc(size); } 73 void operator delete (void *addr, size_t, Allocator &alloc) throw() 74 { return alloc.free(addr); } 75 static void destroy(HandleContext *context, Allocator &alloc) throw() 76 { context->~HandleContext(); alloc.free(context); } 77 78 class Maker; // deluxe builder 79 80#if __GNUC__ > 2 81private: 82 void operator delete (void *addr) throw() { assert(0); } 83#endif 84 85protected: 86 // Locking protocol, courtesy of HandleObject. 87 // This locks the underlying attachment. 88 void lock(); 89 bool tryLock(); 90 91private: 92 void *extent; // extra storage extent in use 93}; 94 95inline HandleContext &enterContext(CSSM_CC_HANDLE h) 96{ 97 return HandleObject::findAndLock<HandleContext>((CSSM_HANDLE)h, CSSM_ERRCODE_INVALID_CONTEXT_HANDLE); 98} 99 100 101// 102// A Maker is a deluxe wrapper around Builder. It creates whole HandleContext 103// objects in one swell foop, handling object locking, construction, error 104// recovery, and all that jazz. A Maker cannot create plain Context objects. 105// 106class HandleContext::Maker : public Context::Builder { 107public: 108 Maker(CSSM_CSP_HANDLE handle) 109 : Context::Builder(HandleObject::findAndLock<CSPAttachment>(handle, CSSM_ERRCODE_INVALID_CSP_HANDLE)), 110 attachment(static_cast<CSPAttachment &>(allocator)), // order dependency(!) 111 locker(attachment, true) 112 { attachment.finishEnter(); } 113 114 CSPAttachment &attachment; 115 116 CSSM_CC_HANDLE operator () (CSSM_CONTEXT_TYPE type, 117 CSSM_ALGORITHMS algorithm); 118 119private: 120 StLock<CountingMutex, &CountingMutex::enter, &CountingMutex::exit> locker; 121}; 122 123#endif //_H_CSSMCONTEXT 124