jcifs.dcerpc.ndr.NdrBuffer Maven / Gradle / Ivy

/* jcifs msrpc client library in Java
 * Copyright (C) 2006  "Michael B. Allen" 
 *                     "Eric Glass" 
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package jcifs.dcerpc.ndr;


import java.util.HashMap;
import java.util.Map;

import jcifs.util.Encdec;
import jcifs.util.Strings;


@SuppressWarnings ( "javadoc" )
public class NdrBuffer {

    private int referent;
    private Map referents;

    private static class Entry {

        public Entry ( int referent, Object obj ) {
            this.referent = referent;
            this.obj = obj;
        }

        final int referent;

        @SuppressWarnings ( "unused" )
        private final Object obj;
    }

    public byte[] buf;
    public int start;
    public int index;
    public int length;
    public NdrBuffer deferred;


    public NdrBuffer ( byte[] buf, int start ) {
        this.buf = buf;
        this.start = this.index = start;
        this.length = 0;
        this.deferred = this;
    }


    public NdrBuffer derive ( int idx ) {
        NdrBuffer nb = new NdrBuffer(this.buf, this.start);
        nb.index = idx;
        nb.deferred = this.deferred;
        return nb;
    }


    public void reset () {
        this.index = this.start;
        this.length = 0;
        this.deferred = this;
    }


    public int getIndex () {
        return this.index;
    }


    public void setIndex ( int index ) {
        this.index = index;
    }


    public int getCapacity () {
        return this.buf.length - this.start;
    }


    public int getTailSpace () {
        return this.buf.length - this.index;
    }


    public byte[] getBuffer () {
        return this.buf;
    }


    public int align ( int boundary, byte value ) {
        int n = align(boundary);
        int i = n;
        while ( i > 0 ) {
            this.buf[ this.index - i ] = value;
            i--;
        }
        return n;
    }


    public void writeOctetArray ( byte[] b, int i, int l ) {
        System.arraycopy(b, i, this.buf, this.index, l);
        advance(l);
    }


    public void readOctetArray ( byte[] b, int i, int l ) {
        System.arraycopy(this.buf, this.index, b, i, l);
        advance(l);
    }


    public int getLength () {
        return this.deferred.length;
    }


    public void setLength ( int length ) {
        this.deferred.length = length;
    }


    public void advance ( int n ) {
        this.index += n;
        if ( ( this.index - this.start ) > this.deferred.length ) {
            this.deferred.length = this.index - this.start;
        }
    }


    public int align ( int boundary ) {
        int m = boundary - 1;
        int i = this.index - this.start;
        int n = ( ( i + m ) & ~m ) - i;
        advance(n);
        return n;
    }


    public void enc_ndr_small ( int s ) {
        this.buf[ this.index ] = (byte) ( s & 0xFF );
        advance(1);
    }


    public int dec_ndr_small () {
        int val = this.buf[ this.index ] & 0xFF;
        advance(1);
        return val;
    }


    public void enc_ndr_short ( int s ) {
        align(2);
        Encdec.enc_uint16le((short) s, this.buf, this.index);
        advance(2);
    }


    public int dec_ndr_short () {
        align(2);
        int val = Encdec.dec_uint16le(this.buf, this.index);
        advance(2);
        return val;
    }


    public void enc_ndr_long ( int l ) {
        align(4);
        Encdec.enc_uint32le(l, this.buf, this.index);
        advance(4);
    }


    public int dec_ndr_long () {
        align(4);
        int val = Encdec.dec_uint32le(this.buf, this.index);
        advance(4);
        return val;
    }


    public void enc_ndr_hyper ( long h ) {
        align(8);
        Encdec.enc_uint64le(h, this.buf, this.index);
        advance(8);
    }


    public long dec_ndr_hyper () {
        align(8);
        long val = Encdec.dec_uint64le(this.buf, this.index);
        advance(8);
        return val;
    }


    /* float */
    /* double */
    public void enc_ndr_string ( String s ) {
        align(4);
        int i = this.index;
        int len = s.length();
        Encdec.enc_uint32le(len + 1, this.buf, i);
        i += 4;
        Encdec.enc_uint32le(0, this.buf, i);
        i += 4;
        Encdec.enc_uint32le(len + 1, this.buf, i);
        i += 4;
        System.arraycopy(Strings.getUNIBytes(s), 0, this.buf, i, len * 2);
        i += len * 2;
        this.buf[ i++ ] = (byte) '\0';
        this.buf[ i++ ] = (byte) '\0';
        advance(i - this.index);
    }


    public String dec_ndr_string () throws NdrException {
        align(4);
        int i = this.index;
        String val = null;
        int len = Encdec.dec_uint32le(this.buf, i);
        i += 12;
        if ( len != 0 ) {
            len--;
            int size = len * 2;
            if ( size < 0 || size > 0xFFFF )
                throw new NdrException(NdrException.INVALID_CONFORMANCE);
            val = Strings.fromUNIBytes(this.buf, i, size);
            i += size + 2;
        }
        advance(i - this.index);
        return val;
    }


    private int getDceReferent ( Object obj ) {
        Entry e;

        if ( this.referents == null ) {
            this.referents = new HashMap<>();
            this.referent = 1;
        }

        if ( ( e = this.referents.get(obj) ) == null ) {
            e = new Entry(this.referent++, obj);
            this.referents.put(obj, e);
        }

        return e.referent;
    }


    public void enc_ndr_referent ( Object obj, int type ) {
        if ( obj == null ) {
            enc_ndr_long(0);
            return;
        }
        switch ( type ) {
        case 1: /* unique */
        case 3: /* ref */
            enc_ndr_long(System.identityHashCode(obj));
            return;
        case 2: /* ptr */
            enc_ndr_long(getDceReferent(obj));
            return;
        }
    }


    @Override
    public String toString () {
        return "start=" + this.start + ",index=" + this.index + ",length=" + getLength();
    }
}