com.gc.iotools.fmt.decoders.Pkcs7Decoder.java Source code

Introduction

Here is the source code for com.gc.iotools.fmt.decoders.Pkcs7Decoder.java

Source

package com.gc.iotools.fmt.decoders;

/*
 * Copyright (c) 2008, 2014 Gabriele Contini. This source code is released
 * under the BSD License.
 */
import java.io.IOException;
import java.io.InputStream;

import org.bouncycastle.cms.CMSException;
import org.bouncycastle.cms.CMSSignedDataParser;
import org.bouncycastle.cms.CMSTypedStream;
import org.bouncycastle.operator.OperatorCreationException;
import org.bouncycastle.operator.jcajce.JcaDigestCalculatorProviderBuilder;

import com.gc.iotools.fmt.base.Decoder;
import com.gc.iotools.fmt.base.FormatEnum;

/**
 * Extract original document from a PKCS#7 signed document.
 * 
 * @author dvd.smnt
 * @since 1.2.0
 * @see Decoder
 */
public class Pkcs7Decoder implements Decoder {

    /**
     * {@inheritDoc}
     */
    @Override
    public InputStream decode(final InputStream istream) throws IOException {
        CMSSignedDataParser sdp;
        try {
            sdp = new CMSSignedDataParser(new JcaDigestCalculatorProviderBuilder().setProvider("BC").build(),
                    istream);
        } catch (final CMSException e) {
            final IOException e1 = new IOException("Error parsing PKCS7 content");
            e1.initCause(e);
            throw e1;
        } catch (OperatorCreationException e) {
            final IOException e1 = new IOException("Error initializing PKCS7 decoder.");
            e1.initCause(e);
            throw e1;
        }
        final CMSTypedStream ts = sdp.getSignedContent();
        return ts.getContentStream();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public FormatEnum getFormat() {
        return FormatEnum.PKCS7;
    }

}