org.bouncycastle.asn1.cms.RecipientInfo.java Source code

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Here is the source code for org.bouncycastle.asn1.cms.RecipientInfo.java

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package org.bouncycastle.asn1.cms;

import org.bouncycastle.asn1.ASN1Choice;
import org.bouncycastle.asn1.ASN1Encodable;
import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1Object;
import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.asn1.ASN1TaggedObject;
import org.bouncycastle.asn1.DERTaggedObject;

/**
 * <a href="http://tools.ietf.org/html/rfc5652#section-6.2">RFC 5652</a>:
 * Content encryption key delivery mechanisms.
 * <p>
 * <pre>
 * RecipientInfo ::= CHOICE {
 *     ktri      KeyTransRecipientInfo,
 *     kari  [1] KeyAgreeRecipientInfo,
 *     kekri [2] KEKRecipientInfo,
 *     pwri  [3] PasswordRecipientInfo,
 *     ori   [4] OtherRecipientInfo }
 * </pre>
 */
public class RecipientInfo extends ASN1Object implements ASN1Choice {
    ASN1Encodable info;

    public RecipientInfo(KeyTransRecipientInfo info) {
        this.info = info;
    }

    public RecipientInfo(KeyAgreeRecipientInfo info) {
        this.info = new DERTaggedObject(false, 1, info);
    }

    public RecipientInfo(KEKRecipientInfo info) {
        this.info = new DERTaggedObject(false, 2, info);
    }

    public RecipientInfo(PasswordRecipientInfo info) {
        this.info = new DERTaggedObject(false, 3, info);
    }

    public RecipientInfo(OtherRecipientInfo info) {
        this.info = new DERTaggedObject(false, 4, info);
    }

    public RecipientInfo(ASN1Primitive info) {
        this.info = info;
    }

    /**
     * Return a RecipientInfo object from the given object.
     * <p>
     * Accepted inputs:
     * <ul>
     * <li> null &rarr; null
     * <li> {@link RecipientInfo} object
     * <li> {@link org.bouncycastle.asn1.ASN1Sequence#getInstance(java.lang.Object) ASN1Sequence} input formats with RecipientInfo structure inside
     * <li> {@link org.bouncycastle.asn1.ASN1TaggedObject#getInstance(java.lang.Object) ASN1TaggedObject} input formats with RecipientInfo structure inside
     * </ul>
     *
     * @param o the object we want converted.
     * @exception IllegalArgumentException if the object cannot be converted.
     */
    public static RecipientInfo getInstance(Object o) {
        if (o == null || o instanceof RecipientInfo) {
            return (RecipientInfo) o;
        } else if (o instanceof ASN1Sequence) {
            return new RecipientInfo((ASN1Sequence) o);
        } else if (o instanceof ASN1TaggedObject) {
            return new RecipientInfo((ASN1TaggedObject) o);
        }

        throw new IllegalArgumentException("unknown object in factory: " + o.getClass().getName());
    }

    public ASN1Integer getVersion() {
        if (info instanceof ASN1TaggedObject) {
            ASN1TaggedObject o = (ASN1TaggedObject) info;

            switch (o.getTagNo()) {
            case 1:
                return KeyAgreeRecipientInfo.getInstance(o, false).getVersion();
            case 2:
                return getKEKInfo(o).getVersion();
            case 3:
                return PasswordRecipientInfo.getInstance(o, false).getVersion();
            case 4:
                return new ASN1Integer(0); // no syntax version for OtherRecipientInfo
            default:
                throw new IllegalStateException("unknown tag");
            }
        }

        return KeyTransRecipientInfo.getInstance(info).getVersion();
    }

    public boolean isTagged() {
        return (info instanceof ASN1TaggedObject);
    }

    public ASN1Encodable getInfo() {
        if (info instanceof ASN1TaggedObject) {
            ASN1TaggedObject o = (ASN1TaggedObject) info;

            switch (o.getTagNo()) {
            case 1:
                return KeyAgreeRecipientInfo.getInstance(o, false);
            case 2:
                return getKEKInfo(o);
            case 3:
                return PasswordRecipientInfo.getInstance(o, false);
            case 4:
                return OtherRecipientInfo.getInstance(o, false);
            default:
                throw new IllegalStateException("unknown tag");
            }
        }

        return KeyTransRecipientInfo.getInstance(info);
    }

    private KEKRecipientInfo getKEKInfo(ASN1TaggedObject o) {
        if (o.isExplicit()) { // compatibilty with erroneous version
            return KEKRecipientInfo.getInstance(o, true);
        } else {
            return KEKRecipientInfo.getInstance(o, false);
        }
    }

    /**
     * Produce an object suitable for an ASN1OutputStream.
     */
    public ASN1Primitive toASN1Primitive() {
        return info.toASN1Primitive();
    }
}