001/**
002 * Copyright 2016 Emmanuel Bourg
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package net.jsign.pe;
018
019import java.io.IOException;
020import java.nio.ByteBuffer;
021import java.nio.ByteOrder;
022
023import org.bouncycastle.asn1.ASN1InputStream;
024import org.bouncycastle.asn1.cms.ContentInfo;
025import org.bouncycastle.cms.CMSException;
026import org.bouncycastle.cms.CMSProcessable;
027import org.bouncycastle.cms.CMSSignedData;
028
029/**
030 * Entry of the certificate table.
031 * 
032 * @author Emmanuel Bourg
033 * @since 1.3
034 */
035public class CertificateTableEntry {
036
037    private int size;
038    private int revision;
039    private int type;
040    private byte[] content;
041    private CMSSignedData signature;
042
043    CertificateTableEntry(PEFile peFile, long index) throws IOException {
044        size = (int) peFile.readDWord(index, 0);
045        if (size < 8 || size > peFile.channel.size() - index) {
046            throw new IOException("Invalid certificate table size: " + size);
047        }
048        revision = peFile.readWord(index, 4);
049        type = peFile.readWord(index, 6);
050        content = new byte[size - 8];
051        peFile.read(content, index, 8);
052    }
053
054    public CertificateTableEntry(CMSSignedData signature) throws IOException {
055        setSignature(signature);
056    }
057
058    public int getSize() {
059        return size;
060    }
061
062    public CMSSignedData getSignature() throws CMSException {
063        if (type != CertificateType.PKCS_SIGNED_DATA.getValue()) {
064            throw new UnsupportedOperationException("Unsupported certificate type: " + type);
065        }
066        
067        if (revision != 0x0200) {
068            throw new UnsupportedOperationException("Unsupported certificate revision: " + revision);
069        }
070        
071        if (signature == null) {
072            try {
073                signature = new CMSSignedData((CMSProcessable) null, ContentInfo.getInstance(new ASN1InputStream(content).readObject()));
074            } catch (IOException e) {
075                throw new IllegalArgumentException("Failed to construct ContentInfo from byte[]: ", e);
076            }
077        }
078        
079        return signature;
080    }
081
082    public void setSignature(CMSSignedData signature) throws IOException {
083        this.signature = signature;
084        byte[] content = signature.toASN1Structure().getEncoded("DER");
085        this.content = pad(content, 8);
086        this.size = this.content.length + 8;
087        this.type = CertificateType.PKCS_SIGNED_DATA.getValue();
088    }
089
090    private byte[] pad(byte[] data, int multiple) {
091        if (data.length % multiple == 0) {
092            return data;
093        } else {
094            byte[] copy = new byte[data.length + (multiple - data.length % multiple)];
095            System.arraycopy(data, 0, copy, 0, data.length);
096            return copy;
097        }
098    }
099
100    public byte[] toBytes() {
101        ByteBuffer buffer = ByteBuffer.allocate(size);
102        buffer.order(ByteOrder.LITTLE_ENDIAN);
103        buffer.putInt(buffer.limit());
104        buffer.putShort((short) 0x0200);
105        buffer.putShort(CertificateType.PKCS_SIGNED_DATA.getValue());
106        buffer.put(content);
107        
108        return buffer.array();
109    }
110}