Security-28.tar.gz

[apple/security.git] / cdsa / cdsa_utilities / cssmdata.h

/*
 * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved.
 * 
 * The contents of this file constitute Original Code as defined in and are
 * subject to the Apple Public Source License Version 1.2 (the 'License').
 * You may not use this file except in compliance with the License. Please obtain
 * a copy of the License at http://www.apple.com/publicsource and read it before
 * using this file.
 * 
 * This 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.
 */


//
// cssmdata.h -- Manager different CssmData types
//
#ifndef _H_CDSA_UTILITIES_CSSMDATA
#define _H_CDSA_UTILITIES_CSSMDATA

#include <Security/utilities.h>
#include <Security/cssmalloc.h>
#include <Security/refcount.h>

#ifdef _CPP_CDSA_UTILITIES_CSSMDATA
#pragma export on
#endif

namespace Security
{

//
// The following pseudo-code describes what (at minimum) is required for a class
// to be a "PseudoData". PseudoData arguments are used in templates.
//
// class PseudoData {
//      void *data() const ...
//  size_t length() const ...
//  operator const CssmData &() const ...
// }
//
// All this can be satisfied, of course, by inheriting form CssmData.
//


//
// A common virtual parent for CssmData-like objects that actively manage the
// allocation status of their data blob. Note that this is about allocating
// the data(), not the CssmData structure itself.
// The ManagedData layer provides for little active memory management, since
// the underlying strategies are potentially very disparate. It does however
// have a well defined interface for *yielding up* its data for copying or transfer.
//
class CssmManagedData {
public:
        CssmManagedData(CssmAllocator &alloc) : allocator(alloc) { }
        virtual ~CssmManagedData();
        
        CssmAllocator &allocator;
        
        virtual operator const CssmData & () const { return get(); }
        template <class T> T *data() const      { return reinterpret_cast<T *>(data()); }
        void *data() const                                      { return get().data(); }
        size_t length() const                           { return get().length(); }
        
        virtual CssmData &get() const throw() = 0; // get shared copy, no ownership change
        virtual CssmData release() = 0;         // give up copy, ownership is transferred
        virtual void reset() = 0;                       // give up copy, data is discarded
};


//
// A CssmOwnedData is a CssmManagedData that unilaterally owns its data storage.
// It has its CssmData object provided during construction.
//
class CssmOwnedData : public CssmManagedData {
public:
        CssmOwnedData(CssmAllocator &alloc, CssmData &mine) : CssmManagedData(alloc), referent(mine) { }

        CssmOwnedData(CssmAllocator &alloc, CSSM_DATA &mine)
        : CssmManagedData(alloc), referent(CssmData::overlay(mine)) { referent.clear(); }
        
        //
        // Basic retrievals (this echoes features of CssmData)
        //
        operator void * () const                { return referent; }
        operator char * () const                { return referent; }
        operator signed char * () const  { return referent; }
        operator unsigned char * () const { return referent; }
        
        operator bool () const                  { return referent; }
        bool operator ! () const                { return !referent; }
        
        size_t length() const                   { return referent.length(); }

        
        //
        // Basic allocators
        //
        void *malloc(size_t len)
        {
                // pseudo-atomic reallocation semantics
                CssmAutoPtr<uint8> alloc(allocator, allocator.malloc<uint8>(len));
                reset();
                return referent = CssmData(alloc.release(), len);
        }
        
        void *realloc(size_t newLen)
        {
                // CssmAllocator::realloc() should be pseudo-atomic (i.e. throw on error)
                return referent = CssmData(allocator.realloc<uint8>(referent.data(), newLen), newLen);
        }
    
        void length(size_t len)                 { realloc(len); }


        //
        // Manipulate existing data
        //
        void *append(const void *addData, size_t addLength)
        {
                size_t oldLength = length();
                realloc(oldLength + addLength);
                return memcpy(referent.at(oldLength), addData, addLength);
        }
        
        void *append(const CssmData &data)
        { return append(data.data(), data.length()); }
        
        //
        // set() replaces current data with new, taking over ownership to the extent possible.
        //
        template <class T>
        void set(T *data, size_t length)
        {
                // assume that data was allocated by our allocator -- we can't be sure
                reset();
                referent = CssmData(data, length);
        }
        
        void set(CssmManagedData &source);
        void set(const CSSM_DATA &source)       { set(source.Data, source.Length); }
        // NOTE: General template set() cannot be used because all subclasses of CssmManagedData
        // need to receive the special handling above. Use set(*.data(), *.length()) instead.


        //
        // copy() replaces current data with new, making a copy and leaving
        // the source intact.
        //
        template <class T>
        void copy(const T *data, size_t length)
        {
                // don't leave any open windows for Mr. Murphy
                CssmAutoPtr<void> newData(allocator, memcpy(allocator.malloc(length), data, length));
                reset();
                referent = CssmData(newData.release(), length);
        }
        
        void copy(const CssmData &source)
        { if (&source != &referent) copy(source.data(), source.length()); }
        void copy(const CSSM_DATA &source)
        { if (&source != &referent) copy(source.Data, source.Length); }
        void copy(CssmManagedData &source)              { copy(source.get()); }
        template <class Data>
        void copy(const Data &source)                   { copy(source.data(), source.length()); }

        
        //
        // Assignment conservatively uses copy if allocator unknown, set if known
        //
        void operator = (CssmManagedData &source) { set(source); }
        void operator = (CssmOwnedData &source) { set(source); }
        void operator = (const CSSM_DATA &source) { copy(source); }
        
        CssmData &get() const throw()                   { return referent; }
        
protected:
        CssmData &referent;
};


//
// A CssmAutoData is a CssmOwnedData that includes its CssmData object.
// This is the very simple case: The object includes ownership, data object,
// and data storage.
//
class CssmAutoData : public CssmOwnedData {
public:
        CssmAutoData(CssmAllocator &alloc) : CssmOwnedData(alloc, mData) { }
        
        template <class Data>
        CssmAutoData(CssmAllocator &alloc, const Data &source) : CssmOwnedData(alloc, mData)
        { *this = source; }
        
        explicit CssmAutoData(CssmManagedData &source) : CssmOwnedData(source.allocator, mData)
        { set(source); }
        
        CssmAutoData(CssmAllocator &alloc, const void *data, size_t length)
        : CssmOwnedData(alloc, mData)   { copy(data, length); }
        
        ~CssmAutoData()                                 { allocator.free(mData); }
        
        CssmData release();
        void reset();
        
        // assignment (not usefully inherited)
        void operator = (CssmManagedData &source)               { set(source); }
        void operator = (CssmOwnedData &source)                 { set(source); }
        void operator = (CssmAutoData &source)                  { set(source); }
        template <class Data>
        void operator = (const Data &source)                    { copy(source); }

private:
        CssmData mData;
};


//
// A CssmRemoteData is a CssmOwnedData that uses an external CssmData object.
// Its release operation clears an internal ownership flag but does not clear
// the CssmData values so they can be used to return values to an outside scope.
//
class CssmRemoteData : public CssmOwnedData {
public:
        CssmRemoteData(CssmAllocator &alloc, CssmData &mine)
        : CssmOwnedData(alloc, mine), iOwnTheData(true) { }
        
        CssmRemoteData(CssmAllocator &alloc, CSSM_DATA &mine)
        : CssmOwnedData(alloc, mine), iOwnTheData(true) { }
        
        ~CssmRemoteData()
        { if (iOwnTheData) allocator.free(referent); }
        
        CssmData release();
        void reset();
        
        // assignment (not usefully inherited)
        void operator = (CssmManagedData &source)               { set(source); }
        void operator = (CssmOwnedData &source)                 { set(source); }
        void operator = (CssmAutoData &source)                  { set(source); }
        template <class Data>
        void operator = (const Data &source)                    { copy(source); }
        
private:
        bool iOwnTheData;
};


//
// CssmPolyData
//
// Used by functions that take a CssmData and would like to allow it to be
// initialized with a static string, int or other basic type.  The function *must*
// copy the Data of the CssmPolyData when doing so if it is to be used
// after the function returns.  (For example by creating a CssmDataContainer from it).
class CssmPolyData : public CssmData {
        template <class T>
        uint8 *set(const T &it)
        { return const_cast<uint8 *>(reinterpret_cast<const uint8 *>(&it)); }
public:
        template <class char_T>
        CssmPolyData(const char_T *s) : CssmData(const_cast<char_T *>(s), strlen(s)) {}
        CssmPolyData(const string &s) : CssmData(const_cast<char *>(s.c_str()), s.size()) {}
        CssmPolyData(const CSSM_DATA &data) : CssmData(data.Data, data.Length) {}

        // Don't use a template constructor (for T &) here - it would eat way too much
        CssmPolyData(const bool &t) : CssmData(set(t), sizeof(t)) { }
        CssmPolyData(const uint32 &t) : CssmData(set(t), sizeof(t)) { }
        CssmPolyData(const sint32 &t) : CssmData(set(t), sizeof(t)) { }
        CssmPolyData(const sint64 &t) : CssmData(set(t), sizeof(t)) { }
        CssmPolyData(const double &t) : CssmData(set(t), sizeof(t)) { }
};

class CssmDateData : public CssmData
{
public:
        CssmDateData(const CSSM_DATE &date);
private:
        uint8 buffer[8];
};

class CssmGuidData : public CssmData
{
public:
        CssmGuidData(const CSSM_GUID &guid);
private:
        char buffer[Guid::stringRepLength + 1];
};


//
// CssmDLPolyData
//
class CssmDLPolyData
{
public:
        CssmDLPolyData(const CSSM_DATA &data, CSSM_DB_ATTRIBUTE_FORMAT format)
        : mData(CssmData::overlay(data)), mFormat(format) {}

        // @@@ Don't use assert, but throw an exception.
        // @@@ Do a size check on mData as well.

        // @@@ This method is dangerous since the returned string is not guaranteed to be zero terminated.
        operator const char *() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_STRING
               || mFormat == CSSM_DB_ATTRIBUTE_FORMAT_TIME_DATE);
                return reinterpret_cast<const char *>(mData.Data);
        }
        operator bool() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_UINT32 || mFormat == CSSM_DB_ATTRIBUTE_FORMAT_SINT32);
                return *reinterpret_cast<uint32 *>(mData.Data);
        }
        operator uint32() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_UINT32);
                return *reinterpret_cast<uint32 *>(mData.Data);
        }
        operator const uint32 *() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_MULTI_UINT32);
                return reinterpret_cast<const uint32 *>(mData.Data);
        }
        operator sint32() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_SINT32);
                return *reinterpret_cast<sint32 *>(mData.Data);
        }
        operator double() const
        {
                assert(mFormat == CSSM_DB_ATTRIBUTE_FORMAT_REAL);
                return *reinterpret_cast<double *>(mData.Data);
        }
        operator CSSM_DATE () const;
        operator Guid () const;
        operator const CssmData &() const
        {
                return mData;
        }

private:
        const CssmData &mData;
        CSSM_DB_ATTRIBUTE_FORMAT mFormat;
};


//
// Non POD refcounted CssmData wrapper that own the data it refers to.
//
class CssmDataContainer : public CssmData, public RefCount
{
public:
    CssmDataContainer(CssmAllocator &inAllocator = CssmAllocator::standard()) :
        CssmData(), mAllocator(inAllocator) {}
        template <class T>
    CssmDataContainer(const T *data, size_t length, CssmAllocator &inAllocator = CssmAllocator::standard()) :
        CssmData(inAllocator.malloc(length), length), mAllocator(inAllocator) 
        { if (length) ::memcpy(Data, data, length); }
        void clear() { if (Data) { mAllocator.free(Data); Data = NULL; Length = 0; } }
        ~CssmDataContainer() { if (Data) mAllocator.free(Data); }
        void append(const CssmPolyData &data)
        {
                uint32 newLength = Length + data.Length;
                Data = reinterpret_cast<uint8 *>(mAllocator.realloc(Data, newLength));
                memcpy(Data + Length, data.Data, data.Length);
                Length = newLength;
        }
        CssmDataContainer(const CssmDataContainer &other)
        : mAllocator(other.mAllocator)
        {
                Data = reinterpret_cast<uint8 *>(mAllocator.malloc(other.Length));
                memcpy(Data, other.Data, other.Length);
                Length = other.Length;
        }
        CssmDataContainer & operator = (const CSSM_DATA &other)
        {
                clear();
                Data = reinterpret_cast<uint8 *>(mAllocator.malloc(other.Length));
                memcpy(Data, other.Data, other.Length);
                Length = other.Length;
                return *this;
        }

public:
        CssmAllocator &mAllocator;

private:
        operator CssmDataContainer * () const;  // prohibit conversion-to-my-pointer
};

//
// CSSM_OIDs are CSSM_DATAs but will probably have different wrapping characteristics.
//
typedef CssmDataContainer CssmOidContainer;

template <class Container>
class CssmBuffer : public RefPointer<Container>
{
public:
    CssmBuffer() : RefPointer<Container>(new Container()) {} // XXX This should may just set ptr to NULL.
        template <class T>
    CssmBuffer(const T *data, size_t length, CssmAllocator &inAllocator = CssmAllocator::standard()) :
        RefPointer<Container>(new Container(data, length, inAllocator)) {}
    CssmBuffer(const CSSM_DATA &data, CssmAllocator &inAllocator = CssmAllocator::standard()) :
        RefPointer<Container>(new Container(data.Data, data.Length, inAllocator)) {}
        CssmBuffer(const CssmBuffer& other) : RefPointer<Container>(other) {}
        CssmBuffer(Container *p) : RefPointer<Container>(p) {}
        bool CssmBuffer::operator < (const CssmBuffer &other) const { return (**this) < (*other); }
};

} // end namespace Security

#ifdef _CPP_CSSMDATA
#pragma export off
#endif

#endif // _H_CDSA_UTILITIES_CSSMDATA