| package org.bouncycastle.asn1; |
| |
| import java.io.IOException; |
| import java.util.Enumeration; |
| |
| /** |
| * The DLSet encodes ASN.1 SET value without element ordering, |
| * and always using definite length form. |
| * <hr> |
| * <h2>X.690</h2> |
| * <h3>8: Basic encoding rules</h3> |
| * <h4>8.11 Encoding of a set value </h4> |
| * <b>8.11.1</b> The encoding of a set value shall be constructed |
| * <p> |
| * <b>8.11.2</b> The contents octets shall consist of the complete |
| * encoding of a data value from each of the types listed in the |
| * ASN.1 definition of the set type, in an order chosen by the sender, |
| * unless the type was referenced with the keyword |
| * <b>OPTIONAL</b> or the keyword <b>DEFAULT</b>. |
| * <p> |
| * <b>8.11.3</b> The encoding of a data value may, but need not, |
| * be present for a type which was referenced with the keyword |
| * <b>OPTIONAL</b> or the keyword <b>DEFAULT</b>. |
| * <blockquote> |
| * NOTE — The order of data values in a set value is not significant, |
| * and places no constraints on the order during transfer |
| * </blockquote> |
| * <h3>9: Canonical encoding rules</h3> |
| * <h4>9.3 Set components</h4> |
| * The encodings of the component values of a set value shall |
| * appear in an order determined by their tags as specified |
| * in 8.6 of ITU-T Rec. X.680 | ISO/IEC 8824-1. |
| * Additionally, for the purposes of determining the order in which |
| * components are encoded when one or more component is an untagged |
| * choice type, each untagged choice type is ordered as though it |
| * has a tag equal to that of the smallest tag in that choice type |
| * or any untagged choice types nested within. |
| * <h3>10: Distinguished encoding rules</h3> |
| * <h4>10.3 Set components</h4> |
| * The encodings of the component values of a set value shall appear |
| * in an order determined by their tags as specified |
| * in 8.6 of ITU-T Rec. X.680 | ISO/IEC 8824-1. |
| * <blockquote> |
| * NOTE — Where a component of the set is an untagged choice type, |
| * the location of that component in the ordering will depend on |
| * the tag of the choice component being encoded. |
| * </blockquote> |
| * <h3>11: Restrictions on BER employed by both CER and DER</h3> |
| * <h4>11.5 Set and sequence components with default value </h4> |
| * The encoding of a set value or sequence value shall not include |
| * an encoding for any component value which is equal to |
| * its default value. |
| */ |
| public class DLSet |
| extends ASN1Set |
| { |
| private int bodyLength = -1; |
| |
| /** |
| * create an empty set |
| */ |
| public DLSet() |
| { |
| } |
| |
| /** |
| * @param obj - a single object that makes up the set. |
| */ |
| public DLSet( |
| ASN1Encodable obj) |
| { |
| super(obj); |
| } |
| |
| /** |
| * @param v - a vector of objects making up the set. |
| */ |
| public DLSet( |
| ASN1EncodableVector v) |
| { |
| super(v, false); |
| } |
| |
| /** |
| * create a set from an array of objects. |
| */ |
| public DLSet( |
| ASN1Encodable[] a) |
| { |
| super(a, false); |
| } |
| |
| private int getBodyLength() |
| throws IOException |
| { |
| if (bodyLength < 0) |
| { |
| int length = 0; |
| |
| for (Enumeration e = this.getObjects(); e.hasMoreElements();) |
| { |
| Object obj = e.nextElement(); |
| |
| length += ((ASN1Encodable)obj).toASN1Primitive().toDLObject().encodedLength(); |
| } |
| |
| bodyLength = length; |
| } |
| |
| return bodyLength; |
| } |
| |
| int encodedLength() |
| throws IOException |
| { |
| int length = getBodyLength(); |
| |
| return 1 + StreamUtil.calculateBodyLength(length) + length; |
| } |
| |
| /** |
| * A note on the implementation: |
| * <p> |
| * As DL requires the constructed, definite-length model to |
| * be used for structured types, this varies slightly from the |
| * ASN.1 descriptions given. Rather than just outputting SET, |
| * we also have to specify CONSTRUCTED, and the objects length. |
| */ |
| void encode( |
| ASN1OutputStream out) |
| throws IOException |
| { |
| ASN1OutputStream dOut = out.getDLSubStream(); |
| int length = getBodyLength(); |
| |
| out.write(BERTags.SET | BERTags.CONSTRUCTED); |
| out.writeLength(length); |
| |
| for (Enumeration e = this.getObjects(); e.hasMoreElements();) |
| { |
| Object obj = e.nextElement(); |
| |
| dOut.writeObject((ASN1Encodable)obj); |
| } |
| } |
| } |