ext_wr.c

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/****************************************************************************
*                                                                           *
*                       Certificate Attribute Write Routines                *
*                        Copyright Peter Gutmann 1996-2008                  *
*                                                                           *
****************************************************************************/

#if defined( INC_ALL )
  #include "cert.h"
  #include "certattr.h"
  #include "asn1.h"
  #include "asn1_ext.h"
#else
  #include "cert/cert.h"
  #include "cert/certattr.h"
  #include "enc_dec/asn1.h"
  #include "enc_dec/asn1_ext.h"
#endif /* Compiler-specific includes */

#ifdef USE_CERTIFICATES

/****************************************************************************
*                                                                           *
*                               Utility Routines                            *
*                                                                           *
****************************************************************************/

/* Get the encoding information needed to encode an attribute */

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2, 3 ) ) \
static int getAttributeEncodingInfo( const ATTRIBUTE_LIST *attributeListPtr,
                                     OUT_OPT_PTR \
                                        ATTRIBUTE_INFO **attributeInfoPtrPtr,
                                     OUT_INT_Z int *attributeDataSize )
    {
    const ATTRIBUTE_INFO *attributeInfoPtr;
    BOOLEAN isConstructed = FALSE;

    assert( isReadPtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );
    assert( isWritePtr( attributeInfoPtrPtr, sizeof( ATTRIBUTE_INFO * ) ) );
    assert( isWritePtr( attributeDataSize, sizeof( int ) ) );

    /* Clear return value */
    *attributeInfoPtrPtr = NULL;

    /* If it's a constructed attribute then the encoding information for
       the outermost wrapper will be recorded in the encoding FIFO, 
       otherwise it's present directly */
    if( attributeListPtr->fifoEnd > 0 )
        {
        attributeInfoPtr = \
            attributeListPtr->encodingFifo[ attributeListPtr->fifoEnd - 1 ];
        isConstructed = TRUE;
        }
    else
        attributeInfoPtr = attributeListPtr->attributeInfoPtr;
    ENSURES( attributeInfoPtr != NULL );

    /* Determine the size of the attribute payload */
    if( isConstructed && attributeInfoPtr->fieldType != FIELDTYPE_CHOICE )
        {
        *attributeDataSize = ( int ) sizeofObject( \
                attributeListPtr->sizeFifo[ attributeListPtr->fifoEnd - 1 ] );
        }
    else
        *attributeDataSize = attributeListPtr->encodedSize;
    *attributeInfoPtrPtr = ( ATTRIBUTE_INFO * ) attributeInfoPtr;

    return( CRYPT_OK );
    }

#ifdef USE_CMSATTR

/* When we write the attributes as a SET OF Attribute (as CMS does) we have 
   to sort them by encoded value.  This is an incredible nuisance since it 
   requires that each value be encoded and stored in encoded form and then 
   the encoded forms sorted and emitted in that order.  To avoid this hassle 
   we keep a record of the current lowest encoded form and then find the 
   next one by encoding enough information (the SEQUENCE and OID, CMS 
   attributes don't have critical flags) on the fly to distinguish them.  
   This is actually less overhead than storing the encoded form for sorting 
   because there are only a small total number of attributes (usually 3) and 
   we don't have to malloc() storage for each one and manage the stored form 
   if we do things on the fly */

#define ATTR_ENCODED_SIZE   ( 16 + MAX_OID_SIZE )

CHECK_RETVAL_PTR STDC_NONNULL_ARG( ( 1, 2 ) ) \
static ATTRIBUTE_LIST *getNextEncodedAttribute( const ATTRIBUTE_LIST *attributeListPtr,
                                                OUT_BUFFER_FIXED( prevEncodedFormLength ) \
                                                    BYTE *prevEncodedForm,
                                                IN_LENGTH_FIXED( ATTR_ENCODED_SIZE ) \
                                                    const int prevEncodedFormLength )
    {
    const ATTRIBUTE_LIST *currentAttributeListPtr = NULL;
    STREAM stream;
    BYTE currentEncodedForm[ ATTR_ENCODED_SIZE + 8 ];
    BYTE buffer[ ATTR_ENCODED_SIZE + 8 ];
    int iterationCount, status;

    assert( isReadPtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );
    assert( isWritePtr( prevEncodedForm, prevEncodedFormLength ) );

    REQUIRES_N( prevEncodedFormLength == ATTR_ENCODED_SIZE );

    /* Give the current encoded form the maximum possible value */
    memset( buffer, 0, ATTR_ENCODED_SIZE );
    memset( currentEncodedForm, 0xFF, ATTR_ENCODED_SIZE );

    sMemOpen( &stream, buffer, ATTR_ENCODED_SIZE );

    /* Write the known attributes until we reach either the end of the list
       or the first blob-type attribute */
    for( iterationCount = 0;
         attributeListPtr != NULL && \
            !checkAttributeProperty( attributeListPtr,
                                     ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE; 
         iterationCount++ )
        {
        CRYPT_ATTRIBUTE_TYPE attributeID;
        const ATTRIBUTE_INFO *attributeInfoPtr;
        int attributeDataSize;

        /* Get the encoding information for the attribute */
        status = getAttributeEncodingInfo( attributeListPtr, 
                                ( ATTRIBUTE_INFO ** ) &attributeInfoPtr, 
                                &attributeDataSize );
        ENSURES_N( cryptStatusOK( status ) );
        attributeID = attributeListPtr->attributeID;

        /* Write the header and OID */
        sseek( &stream, 0 );
        writeSequence( &stream, sizeofOID( attributeInfoPtr->oid ) + \
                       ( int ) sizeofObject( attributeDataSize ) );
        status = swrite( &stream, attributeInfoPtr->oid,
                         sizeofOID( attributeInfoPtr->oid ) );
        ENSURES_N( cryptStatusOK( status ) );

        /* Check to see whether this is larger than the previous value but 
           smaller than any other one that we've seen.  If it is, remember 
           it.  A full-length memcmp() is safe here because no encoded form 
           can be a prefix of another form so we always exit before we get 
           into the leftover data from previous encodings */
        if( memcmp( prevEncodedForm, buffer, ATTR_ENCODED_SIZE ) < 0 && \
            memcmp( buffer, currentEncodedForm, ATTR_ENCODED_SIZE ) < 0 )
            {
            memcpy( currentEncodedForm, buffer, ATTR_ENCODED_SIZE );
            currentAttributeListPtr = attributeListPtr;
            }

        /* Move on to the next attribute */
        for( /* Continue iterationCount from previous loop */ ;
             attributeListPtr != NULL && \
                attributeListPtr->attributeID == attributeID && \
                iterationCount < FAILSAFE_ITERATIONS_LARGE;
             attributeListPtr = attributeListPtr->next, iterationCount++ );
        }
    ENSURES_N( iterationCount < FAILSAFE_ITERATIONS_LARGE );

    /* Write the blob-type attributes */
    for( /* Continue iterationCount from previous loop */ ;
         attributeListPtr != NULL && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE; 
         attributeListPtr = attributeListPtr->next, iterationCount++ )
        {
        ENSURES_N( checkAttributeProperty( attributeListPtr,
                                           ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) );

        /* Write the header and OID */
        sseek( &stream, 0 );
        writeSequence( &stream, sizeofOID( attributeListPtr->oid ) + \
                       ( int ) sizeofObject( attributeListPtr->valueLength ) );
        status = swrite( &stream, attributeListPtr->oid,
                         sizeofOID( attributeListPtr->oid ) );
        ENSURES_N( cryptStatusOK( status ) );

        /* Check to see whether this is larger than the previous value but
           smaller than any other one that we've seen.  If it is, remember 
           it */
        if( memcmp( prevEncodedForm, buffer, ATTR_ENCODED_SIZE ) < 0 && \
            memcmp( buffer, currentEncodedForm, ATTR_ENCODED_SIZE ) < 0 )
            {
            memcpy( currentEncodedForm, buffer, ATTR_ENCODED_SIZE );
            currentAttributeListPtr = attributeListPtr;
            }
        }
    ENSURES_N( iterationCount < FAILSAFE_ITERATIONS_LARGE );

    sMemDisconnect( &stream );

    /* Remember the encoded form of the attribute and return a pointer to
       it */
    memcpy( prevEncodedForm, currentEncodedForm, ATTR_ENCODED_SIZE );
    return( ( ATTRIBUTE_LIST * ) currentAttributeListPtr );
    }
#endif /* USE_CMSATTR */

/* Determine the size of a set of attributes and validate and preprocess the
   attribute information */

CHECK_RETVAL \
int sizeofAttributes( IN_OPT const ATTRIBUTE_PTR *attributePtr )
    {
    const ATTRIBUTE_LIST *attributeListPtr = attributePtr;
    int signUnrecognised, attributeSize = 0, iterationCount, status;

    assert( attributePtr == NULL || \
            isReadPtr( attributePtr, sizeof( ATTRIBUTE_LIST ) ) );

    /* If there's nothing to write, return now */
    if( attributeListPtr == NULL )
        return( 0 );

    /* Determine the size of the recognised attributes */
    for( iterationCount = 0;
         attributeListPtr != NULL && \
            !checkAttributeProperty( attributeListPtr,
                                     ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE;
         iterationCount++ )
        {
        CRYPT_ATTRIBUTE_TYPE attributeID;
        const ATTRIBUTE_INFO *attributeInfoPtr;
        int attributeDataSize;

        /* Get the encoding information for the attribute */
        status = getAttributeEncodingInfo( attributeListPtr, 
                                ( ATTRIBUTE_INFO ** ) &attributeInfoPtr, 
                                &attributeDataSize );
        ENSURES( cryptStatusOK( status ) );
        attributeID = attributeListPtr->attributeID;
        attributeDataSize = ( int ) sizeofObject( attributeDataSize );

        /* Determine the overall attribute size */
        attributeDataSize += sizeofOID( attributeInfoPtr->oid );
        if( ( attributeInfoPtr->typeInfoFlags & FL_ATTR_CRITICAL ) || \
            ( attributeListPtr->flags & ATTR_FLAG_CRITICAL ) )
            attributeDataSize += sizeofBoolean();
        attributeSize += ( int ) sizeofObject( attributeDataSize );

        /* Skip everything else in the current attribute */
        for( /* Continue iterationCount from previous loop */ ;
             attributeListPtr != NULL && \
                attributeListPtr->attributeID == attributeID && \
                iterationCount < FAILSAFE_ITERATIONS_LARGE;
             attributeListPtr = attributeListPtr->next, iterationCount++ );
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_LARGE );

    /* If we're not going to be signing the blob-type attributes, return */
    krnlSendMessage( DEFAULTUSER_OBJECT_HANDLE, IMESSAGE_GETATTRIBUTE, 
                     &signUnrecognised, 
                     CRYPT_OPTION_CERT_SIGNUNRECOGNISEDATTRIBUTES );
    if( !signUnrecognised )
        return( attributeSize );

    /* Determine the size of the blob-type attributes */
    for( ; attributeListPtr != NULL && \
           iterationCount < FAILSAFE_ITERATIONS_LARGE; 
        attributeListPtr = attributeListPtr->next, iterationCount++ )
        {
        ENSURES( checkAttributeProperty( attributeListPtr,
                                         ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) );

        attributeSize += ( int ) \
                         sizeofObject( sizeofOID( attributeListPtr->oid ) + \
                         sizeofObject( attributeListPtr->valueLength ) );
        if( attributeListPtr->flags & ATTR_FLAG_CRITICAL )
            attributeSize += sizeofBoolean();
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_LARGE );

    return( attributeSize );
    }

/****************************************************************************
*                                                                           *
*                   Attribute/Attribute Field Write Routines                *
*                                                                           *
****************************************************************************/

/* Calculate the size of an attribute field */

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2, 3 ) ) \
static int calculateSpecialFieldSize( const ATTRIBUTE_LIST *attributeListPtr,
                                      const ATTRIBUTE_INFO *attributeInfoPtr,
                                      OUT_LENGTH_SHORT_Z int *payloadSize, 
                                      const int fieldType )
    {
    assert( isReadPtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );
    assert( isReadPtr( attributeInfoPtr, sizeof( ATTRIBUTE_INFO ) ) );
    assert( isWritePtr( payloadSize, sizeof( int ) ) );

    REQUIRES( isBlobField( fieldType ) || \
              ( fieldType == FIELDTYPE_IDENTIFIER ) || \
              ( fieldType > 0 && fieldType < MAX_TAG ) );

    /* Determine the size of the data payload */
    *payloadSize = attributeListPtr->sizeFifo[ attributeListPtr->fifoPos ];

    /* It's a special-case field, the data size is taken from somewhere 
       other than the user-supplied data */
    switch( fieldType )
        {
        case FIELDTYPE_BLOB_ANY:
        case FIELDTYPE_BLOB_BITSTRING:
        case FIELDTYPE_BLOB_SEQUENCE:
            /* Fixed-value blob (as opposed to user-supplied one) */
            return( ( int ) attributeInfoPtr->defaultValue );

        case FIELDTYPE_IDENTIFIER:
            return( sizeofOID( attributeInfoPtr->oid ) );

#if 0   /* 28/9/08 This shouldn't ever occur, defaultValue is only used for
                   FIELDTYPE_BLOB_ANY and BOOLEAN fields */
        case BER_INTEGER:
            return( sizeofShortInteger( attributeInfoPtr->defaultValue ) );
#endif /* 0 */

        case BER_SEQUENCE:
        case BER_SET:
            return( ( int ) sizeofObject( *payloadSize ) );
        }

    retIntError();
    }

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2 ) ) \
static int calculateFieldSize( const ATTRIBUTE_LIST *attributeListPtr,
                               const ATTRIBUTE_INFO *attributeInfoPtr,
                               const int fieldType )
    {
    assert( isReadPtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );
    assert( isReadPtr( attributeInfoPtr, sizeof( ATTRIBUTE_INFO ) ) );

    REQUIRES( fieldType >= FIELDTYPE_TEXTSTRING && fieldType < MAX_TAG );
              /* The default handler at the end can include fields up to 
                 FIELDTYPE_TEXTSTRING */

    switch( fieldType )
        {
        case FIELDTYPE_BLOB_ANY:
        case FIELDTYPE_BLOB_BITSTRING:
        case FIELDTYPE_BLOB_SEQUENCE:
        case BER_OBJECT_IDENTIFIER:
            return( attributeListPtr->valueLength );

        case FIELDTYPE_DN:
            return( sizeofDN( attributeListPtr->value ) );

        case FIELDTYPE_IDENTIFIER:
            return( sizeofOID( attributeInfoPtr->oid ) );

        case BER_BITSTRING:
            return( sizeofBitString( attributeListPtr->intValue ) );

        case BER_BOOLEAN:
            return( sizeofBoolean() );

        case BER_ENUMERATED:
            return( sizeofEnumerated( attributeListPtr->intValue ) );

        case BER_INTEGER:
            return( sizeofShortInteger( attributeListPtr->intValue ) );

        case BER_NULL:
            /* This is stored as a pseudo-numeric value CRYPT_UNUSED so we 
               can't fall through to the default handler */
            return( sizeofNull() );

        case BER_OCTETSTRING:
            return( ( int ) sizeofObject( attributeListPtr->valueLength ) );

        case BER_TIME_GENERALIZED:
            return( sizeofGeneralizedTime() );

        case BER_TIME_UTC:
            return( sizeofUTCTime() );
        }

    return( ( int ) sizeofObject( attributeListPtr->valueLength ) );
    }

/* Write an attribute field */

CHECK_RETVAL STDC_NONNULL_ARG( ( 2 ) ) \
int writeAttributeField( INOUT_OPT STREAM *stream, 
                         INOUT ATTRIBUTE_LIST *attributeListPtr,
                         IN_RANGE( 0, 4 ) const int complianceLevel )
    {
    const BOOLEAN isSpecial = ( attributeListPtr->fifoPos > 0 ) ? TRUE : FALSE;
    const ATTRIBUTE_INFO *attributeInfoPtr = ( isSpecial ) ? \
        attributeListPtr->encodingFifo[ --attributeListPtr->fifoPos ] : \
        attributeListPtr->attributeInfoPtr;
    const void *dataPtr = attributeListPtr->value;
    const int fieldType = attributeInfoPtr->fieldType;
    int tag, size, payloadSize = DUMMY_INIT;

    assert( stream == NULL || isWritePtr( stream, sizeof( STREAM ) ) );
    assert( isWritePtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );

    REQUIRES( complianceLevel >= CRYPT_COMPLIANCELEVEL_OBLIVIOUS && \
              complianceLevel < CRYPT_COMPLIANCELEVEL_LAST );

    /* If this is just a marker for a series of CHOICE alternatives, return
       without doing anything */
    if( fieldType == FIELDTYPE_CHOICE )
        return( CRYPT_OK );

    /* Calculate the size of the encoded data */
    if( isSpecial )
        {
        size = calculateSpecialFieldSize( attributeListPtr, attributeInfoPtr, 
                                          &payloadSize, fieldType );
        }
    else
        {
        size = calculateFieldSize( attributeListPtr, attributeInfoPtr, 
                                   fieldType );
        }
    if( cryptStatusError( size ) )
        return( size );

    /* If we're just calculating the attribute size, don't write any data */
    if( stream == NULL )
        {
        return( ( attributeInfoPtr->encodingFlags & FL_EXPLICIT ) ? \
                ( int ) sizeofObject( size ) : size );
        }

    /* If the field is explicitly tagged, add another layer of wrapping */
    if( attributeInfoPtr->encodingFlags & FL_EXPLICIT )
        writeConstructed( stream, size, attributeInfoPtr->fieldEncodedType );

    /* If the encoded field type differs from the actual field type (because
       if implicit tagging) and we're not specifically using explicit
       tagging and it's not a DN in a GeneralName (which is a tagged IMPLICIT
       SEQUENCE overridden to make it EXPLICIT because of the tagged CHOICE
       encoding rules) set the tag to the encoded field type rather than the
       actual field type */
    if( attributeInfoPtr->fieldEncodedType >= 0 && \
        !( attributeInfoPtr->encodingFlags & FL_EXPLICIT ) && \
        attributeInfoPtr->fieldType != FIELDTYPE_DN )
        tag = attributeInfoPtr->fieldEncodedType;
    else
        tag = DEFAULT_TAG;

    /* Write the data as appropriate */
    if( isSpecial )
        {
        /* If it's a special-case field, the data is taken from somewhere
           other than the user-supplied data */
        switch( fieldType )
            {
            case FIELDTYPE_BLOB_ANY:
            case FIELDTYPE_BLOB_BITSTRING:
            case FIELDTYPE_BLOB_SEQUENCE:
                /* Fixed-value blob (as opposed to user-supplied one) */
                return( swrite( stream, attributeInfoPtr->extraData, size ) );

            case FIELDTYPE_IDENTIFIER:
                return( swrite( stream, attributeInfoPtr->oid, size ) );

#if 0   /* 28/9/08 See comment in calculateSpecialFieldSize() */
            case BER_INTEGER:
                return( writeShortInteger( stream, attributeInfoPtr->defaultValue, 
                                           tag ) );
#endif /* 0 */

            case BER_SEQUENCE:
            case BER_SET:
                if( tag != DEFAULT_TAG )
                    return( writeConstructed( stream, payloadSize, tag ) );
                return( ( fieldType == BER_SET ) ? \
                        writeSet( stream, payloadSize ) : \
                        writeSequence( stream, payloadSize ) );
            }
        
        retIntError();
        }

    /* It's a standard object, take the data from the user-supplied data */
    switch( fieldType )
        {
        case FIELDTYPE_BLOB_ANY:
        case FIELDTYPE_BLOB_BITSTRING:
        case FIELDTYPE_BLOB_SEQUENCE:
            if( tag != DEFAULT_TAG )
                {
                /* This gets a bit messy because the blob is stored in 
                   encoded form in the attribute, to write it as a tagged 
                   value we have to write a different first byte */
                sputc( stream, getFieldEncodedTag( attributeInfoPtr ) );
                return( swrite( stream, ( ( BYTE * ) dataPtr ) + 1,
                                attributeListPtr->valueLength - 1 ) );
                }
            return( swrite( stream, dataPtr, attributeListPtr->valueLength ) );

        case FIELDTYPE_DN:
            return( writeDN( stream, attributeListPtr->value, tag ) );

        case FIELDTYPE_IDENTIFIER:
            ENSURES( tag == DEFAULT_TAG );
            return( swrite( stream, attributeInfoPtr->oid, size ) );

        case FIELDTYPE_TEXTSTRING:
            if( tag == DEFAULT_TAG )
                {
                tag = ( complianceLevel >= CRYPT_COMPLIANCELEVEL_PKIX_PARTIAL ) ? \
                      BER_STRING_UTF8 : BER_STRING_ISO646;
                }
            return( writeCharacterString( stream, dataPtr, 
                                          attributeListPtr->valueLength, 
                                          tag ) );

        case BER_BITSTRING:
            return( writeBitString( stream, ( int ) \
                                    attributeListPtr->intValue, tag ) );

        case BER_BOOLEAN:
            return( writeBoolean( stream, ( BOOLEAN ) \
                                  attributeListPtr->intValue, tag ) );

        case BER_ENUMERATED:
            return( writeEnumerated( stream, ( int ) \
                                     attributeListPtr->intValue, tag ) );

        case BER_INTEGER:
            return( writeShortInteger( stream, attributeListPtr->intValue, 
                                       tag ) );

        case BER_NULL:
            return( writeNull( stream, tag ) );

        case BER_OBJECT_IDENTIFIER:
            if( tag != DEFAULT_TAG )
                {
                /* This gets a bit messy because the OID is stored in 
                   encoded form in the attribute, to write it as a tagged 
                   value we have to write a different first byte */
                sputc( stream, getFieldEncodedTag( attributeInfoPtr ) );
                return( swrite( stream, ( ( BYTE * ) dataPtr ) + 1,
                                attributeListPtr->valueLength - 1 ) );
                }
            return( swrite( stream, dataPtr, 
                            attributeListPtr->valueLength ) );

        case BER_OCTETSTRING:
            return( writeOctetString( stream, dataPtr, 
                                      attributeListPtr->valueLength, 
                                      tag ) );

        case BER_STRING_BMP:
        case BER_STRING_IA5:
        case BER_STRING_ISO646:
        case BER_STRING_NUMERIC:
        case BER_STRING_PRINTABLE:
        case BER_STRING_UTF8:
            return( writeCharacterString( stream, dataPtr, 
                                          attributeListPtr->valueLength,
                                          ( tag == DEFAULT_TAG ) ? \
                                            fieldType : \
                                            MAKE_CTAG_PRIMITIVE( tag ) ) );

        case BER_TIME_GENERALIZED:
            return( writeGeneralizedTime( stream, *( time_t * ) dataPtr, 
                                          tag ) );

        case BER_TIME_UTC:
            return( writeUTCTime( stream, *( time_t * ) dataPtr, tag ) );
        }

    retIntError();
    }

/* Write an attribute */

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2 ) ) \
static int writeAttribute( INOUT STREAM *stream, 
                           INOUT ATTRIBUTE_LIST **attributeListPtrPtr,
                           const BOOLEAN wrapperTagSet, 
                           IN_RANGE( 0, 4 ) const int complianceLevel )
    {
    CRYPT_ATTRIBUTE_TYPE attributeID;
    const ATTRIBUTE_INFO *attributeInfoPtr;
    ATTRIBUTE_LIST *attributeListPtr = *attributeListPtrPtr;
    BOOLEAN isCritical = FALSE;
    int attributeDataSize, iterationCount, status;

    assert( isWritePtr( stream, sizeof( STREAM ) ) );
    assert( isWritePtr( attributeListPtrPtr, sizeof( ATTRIBUTE_LIST * ) ) );
    assert( isReadPtr( *attributeListPtrPtr, sizeof( ATTRIBUTE_LIST ) ) );

    REQUIRES( complianceLevel >= CRYPT_COMPLIANCELEVEL_OBLIVIOUS && \
              complianceLevel < CRYPT_COMPLIANCELEVEL_LAST );

    /* Get the encoding information for the attribute */
    status = getAttributeEncodingInfo( attributeListPtr, 
                                ( ATTRIBUTE_INFO ** ) &attributeInfoPtr, 
                                &attributeDataSize );
    ENSURES( cryptStatusOK( status ) );
    attributeID = attributeListPtr->attributeID;
    if( ( attributeInfoPtr->typeInfoFlags & FL_ATTR_CRITICAL ) || \
        ( attributeListPtr->flags & ATTR_FLAG_CRITICAL ) )
        isCritical = TRUE;

    /* Write the outer SEQUENCE, OID, critical flag (if it's set) and 
       appropriate wrapper for the attribute payload */
    writeSequence( stream, 
                   sizeofOID( attributeInfoPtr->oid ) + \
                   ( isCritical ? sizeofBoolean() : 0 ) + \
                   ( int ) sizeofObject( attributeDataSize ) );
    swrite( stream, attributeInfoPtr->oid,
            sizeofOID( attributeInfoPtr->oid ) );
    if( isCritical )
        writeBoolean( stream, TRUE, DEFAULT_TAG );
    if( wrapperTagSet )
        status = writeSet( stream, attributeDataSize );
    else
        status = writeOctetStringHole( stream, attributeDataSize, 
                                       DEFAULT_TAG );
    if( cryptStatusError( status ) )
        return( status );

    /* Write the current attribute */
    for( iterationCount = 0;
         attributeListPtr != NULL && \
            attributeListPtr->attributeID == attributeID && \
            iterationCount < FAILSAFE_ITERATIONS_MED;
         attributeListPtr = attributeListPtr->next, iterationCount++ )
        {
        int innerIterationCount;
            
        /* Write any encapsulating SEQUENCEs if necessary, followed by the 
           field itself.  In some rare instances we may have a zero-length 
           SEQUENCE (if all the member(s) of the sequence have default 
           values) so we only try to write the member if there's encoding 
           information for it present */
        for( attributeListPtr->fifoPos = attributeListPtr->fifoEnd, \
                innerIterationCount = 0;
             cryptStatusOK( status ) && \
                attributeListPtr->fifoPos > 0 && \
                innerIterationCount < ENCODING_FIFO_SIZE;
             innerIterationCount++ )
            {
            status = writeAttributeField( stream, 
                                    ( ATTRIBUTE_LIST * ) attributeListPtr,
                                    complianceLevel );
            }
        ENSURES( innerIterationCount < ENCODING_FIFO_SIZE );
        if( cryptStatusOK( status ) && \
            attributeListPtr->attributeInfoPtr != NULL )
            {
            status = writeAttributeField( stream, 
                                    ( ATTRIBUTE_LIST * ) attributeListPtr,
                                    complianceLevel );
            }
        if( cryptStatusError( status ) )
            return( status );
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_MED );

    *attributeListPtrPtr = attributeListPtr;
    return( CRYPT_OK );
    }

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2 ) ) \
static int writeBlobAttribute( INOUT STREAM *stream, 
                               INOUT ATTRIBUTE_LIST **attributeListPtrPtr,
                               const BOOLEAN wrapperTagSet, 
                               IN_RANGE( 0, 4 ) const int complianceLevel )
    {
    ATTRIBUTE_LIST *attributeListPtr = *attributeListPtrPtr;
    const BOOLEAN isCritical = \
            ( attributeListPtr->flags & ATTR_FLAG_CRITICAL ) ? TRUE : FALSE;
    int status;

    /* Write the header, OID, critical flag (if present), and payload 
       wrapped up as appropriate */
    writeSequence( stream, 
                   sizeofOID( attributeListPtr->oid ) + \
                   ( isCritical ? sizeofBoolean() : 0 ) + \
                   ( int ) sizeofObject( attributeListPtr->valueLength ) );
    swrite( stream, attributeListPtr->oid,
            sizeofOID( attributeListPtr->oid ) );
    if( isCritical )
        writeBoolean( stream, TRUE, DEFAULT_TAG );
    if( wrapperTagSet )
        writeSet( stream, attributeListPtr->valueLength );
    else
        {
        writeOctetStringHole( stream, attributeListPtr->valueLength, 
                              DEFAULT_TAG );
        }
    status = swrite( stream, attributeListPtr->value,
                     attributeListPtr->valueLength );
    if( cryptStatusOK( status ) )
        *attributeListPtrPtr = attributeListPtr->next;
    return( status );
    }

#ifdef USE_CMSATTR

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2 ) ) \
int writeCmsAttributes( INOUT STREAM *stream, 
                        const ATTRIBUTE_LIST *attributeListPtr,
                        IN_ENUM( CRYPT_CERTTYPE ) const CRYPT_CERTTYPE_TYPE type,
                        IN_LENGTH const int attributeSize,
                        IN_RANGE( 0, 4 ) const int complianceLevel )
    {
    ATTRIBUTE_LIST *currentAttributePtr;
    BYTE currentEncodedForm[ ATTR_ENCODED_SIZE + 8 ];
    int iterationCount, status;

    assert( isWritePtr( stream, sizeof( STREAM ) ) );
    assert( isReadPtr( attributeListPtr, sizeof( ATTRIBUTE_LIST ) ) );

    REQUIRES( type == CRYPT_CERTTYPE_CMS_ATTRIBUTES || \
              type == CRYPT_CERTTYPE_RTCS_REQUEST || \
              type == CRYPT_CERTTYPE_RTCS_RESPONSE );
    REQUIRES( attributeSize > 0 && attributeSize < MAX_INTLENGTH );
    REQUIRES( complianceLevel >= CRYPT_COMPLIANCELEVEL_OBLIVIOUS && \
              complianceLevel < CRYPT_COMPLIANCELEVEL_LAST );

    /* Write the wrapper, depending on the object type */
    if( type == CRYPT_CERTTYPE_RTCS_REQUEST )
        status = writeSet( stream, attributeSize );
    else
        {
        status = writeConstructed( stream, attributeSize, 
                                  ( type == CRYPT_CERTTYPE_CMS_ATTRIBUTES ) ? \
                                    CTAG_SI_AUTHENTICATEDATTRIBUTES : \
                                    CTAG_RP_EXTENSIONS );
        }
    if( cryptStatusError( status ) )
        return( status );

    /* Write the attributes in sorted form */
    memset( currentEncodedForm, 0, ATTR_ENCODED_SIZE ); /* Set lowest encoded form */
    for( currentAttributePtr = getNextEncodedAttribute( attributeListPtr, \
                                                        currentEncodedForm,
                                                        ATTR_ENCODED_SIZE ),
            iterationCount = 0;
         currentAttributePtr != NULL && cryptStatusOK( status ) && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE;
        currentAttributePtr = getNextEncodedAttribute( attributeListPtr,
                                                       currentEncodedForm,
                                                       ATTR_ENCODED_SIZE ),
            iterationCount++ )
        {
        if( checkAttributeProperty( currentAttributePtr,
                                    ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) )
            {
            status = writeBlobAttribute( stream, &currentAttributePtr, TRUE, 
                                         complianceLevel );
            }
        else
            {
            status = writeAttribute( stream, &currentAttributePtr, TRUE, 
                                     complianceLevel );
            }
        if( cryptStatusError( status ) )
            return( status );
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_LARGE );

    return( CRYPT_OK );
    }
#endif /* USE_CMSATTR */

/****************************************************************************
*                                                                           *
*                       Attribute Collection Write Routines                 *
*                                                                           *
****************************************************************************/

/* Write a set of attributes */

CHECK_RETVAL STDC_NONNULL_ARG( ( 1, 2 ) ) \
int writeAttributes( INOUT STREAM *stream, 
                     INOUT ATTRIBUTE_PTR *attributePtr,
                     IN_ENUM_OPT( CRYPT_CERTTYPE ) const CRYPT_CERTTYPE_TYPE type,
                     IN_LENGTH const int attributeSize )
    {
    ATTRIBUTE_LIST *attributeListPtr = attributePtr;
    int signUnrecognised = DUMMY_INIT, complianceLevel, iterationCount;
    int status;

    assert( isWritePtr( stream, sizeof( STREAM ) ) );
    assert( isWritePtr( attributePtr, sizeof( ATTRIBUTE_LIST ) ) );

    REQUIRES( type >= CRYPT_CERTTYPE_NONE && type < CRYPT_CERTTYPE_LAST );
              /* Single CRL entries have the special-case type 
                 CRYPT_CERTTYPE_NONE */
    REQUIRES( attributeSize > 0 && attributeSize < MAX_INTLENGTH );

    /* Some attributes have odd encoding/handling requirements that can 
       cause problems for other software so we only enforce peculiarities 
       required by some standards at higher compliance levels.  In addition 
       we only sign unrecognised attributes if we're explicitly asked to do 
       so by the user */
    status = krnlSendMessage( DEFAULTUSER_OBJECT_HANDLE,
                              IMESSAGE_GETATTRIBUTE, &complianceLevel,
                              CRYPT_OPTION_CERT_COMPLIANCELEVEL );
    if( cryptStatusOK( status ) )
        {
        status = krnlSendMessage( DEFAULTUSER_OBJECT_HANDLE, 
                                  IMESSAGE_GETATTRIBUTE, &signUnrecognised,
                                  CRYPT_OPTION_CERT_SIGNUNRECOGNISEDATTRIBUTES );
        }
    if( cryptStatusError( status ) )
        return( status );

    /* CMS attributes work somewhat differently from normal attributes in 
       that, since they're encoded as a SET OF Attribute, they have to be 
       sorted according to their encoded form before being written.  For 
       this reason we don't write them sorted by OID as with the other 
       attributes but keep writing the next-lowest attribute until they've 
       all been written */
#ifdef USE_CMSATTR
    if( type == CRYPT_CERTTYPE_CMS_ATTRIBUTES || \
        type == CRYPT_CERTTYPE_RTCS_REQUEST || \
        type == CRYPT_CERTTYPE_RTCS_RESPONSE )
        {
        return( writeCmsAttributes( stream, attributeListPtr, type, 
                                    attributeSize, complianceLevel ) );
        }
#endif /* USE_CMSATTR */

    /* Write the appropriate extensions tag for the certificate object and 
       determine how far we can read.  CRLs and OCSP requests/responses have 
       two extension types that have different tagging, per-entry extensions 
       and entire-CRL/request extensions.  To differentiate between the two 
       we write per-entry extensions with a type of CRYPT_CERTTYPE_NONE */
    switch( type )
        {
        case CRYPT_CERTTYPE_CERTIFICATE:
        case CRYPT_CERTTYPE_CRL:
            writeConstructed( stream, ( int ) sizeofObject( attributeSize ),
                              ( type == CRYPT_CERTTYPE_CERTIFICATE ) ? \
                              CTAG_CE_EXTENSIONS : CTAG_CL_EXTENSIONS );
            status = writeSequence( stream, attributeSize );
            break;

        case CRYPT_CERTTYPE_CERTREQUEST:
            writeSequence( stream, sizeofOID( OID_PKCS9_EXTREQ ) + \
                           ( int ) sizeofObject( sizeofObject( attributeSize ) ) );
            swrite( stream, OID_PKCS9_EXTREQ, sizeofOID( OID_PKCS9_EXTREQ ) );
            writeSet( stream, ( int ) sizeofObject( attributeSize ) );
            status = writeSequence( stream, attributeSize );
            break;

        case CRYPT_CERTTYPE_REQUEST_CERT:
        case CRYPT_CERTTYPE_REQUEST_REVOCATION:
            /* No wrapper, extensions are written directly */
            break;

        case CRYPT_CERTTYPE_ATTRIBUTE_CERT:
        case CRYPT_CERTTYPE_PKIUSER:
        case CRYPT_CERTTYPE_NONE:
            status = writeSequence( stream, attributeSize );
            break;

        case CRYPT_CERTTYPE_OCSP_REQUEST:
            writeConstructed( stream, ( int ) sizeofObject( attributeSize ), 
                              CTAG_OR_EXTENSIONS );
            status = writeSequence( stream, attributeSize );
            break;

        case CRYPT_CERTTYPE_OCSP_RESPONSE:
            writeConstructed( stream, ( int ) sizeofObject( attributeSize ), 
                              CTAG_OP_EXTENSIONS );
            status = writeSequence( stream, attributeSize );
            break;

        default:
            retIntError();
        }
    if( cryptStatusError( status ) )
        return( status );

    /* Write the known attributes until we reach either the end of the list
       or the first blob-type attribute */
    for( iterationCount = 0;
         cryptStatusOK( status ) && attributeListPtr != NULL && \
            !checkAttributeProperty( attributeListPtr,
                                     ATTRIBUTE_PROPERTY_BLOBATTRIBUTE ) && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE;
         iterationCount++ )
        {
        status = writeAttribute( stream, &attributeListPtr, FALSE, 
                                 complianceLevel );
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_LARGE );
    if( cryptStatusError( status ) || !signUnrecognised  )
        return( status );

    /* Write the blob-type attributes */
    for( iterationCount = 0;
         attributeListPtr != NULL && cryptStatusOK( status ) && \
            iterationCount < FAILSAFE_ITERATIONS_LARGE;
         iterationCount++ )
        {
        status = writeBlobAttribute( stream, &attributeListPtr, FALSE, 
                                     complianceLevel );
        }
    ENSURES( iterationCount < FAILSAFE_ITERATIONS_LARGE );
    return( status );
    }
#endif /* USE_CERTIFICATES */