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Diffstat (limited to 'core/src/main/java/org/spongycastle/asn1/ASN1Set.java')
| -rw-r--r-- | core/src/main/java/org/spongycastle/asn1/ASN1Set.java | 560 |
1 files changed, 560 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/asn1/ASN1Set.java b/core/src/main/java/org/spongycastle/asn1/ASN1Set.java new file mode 100644 index 00000000..0bc92547 --- /dev/null +++ b/core/src/main/java/org/spongycastle/asn1/ASN1Set.java @@ -0,0 +1,560 @@ +package org.spongycastle.asn1; + +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.util.Enumeration; +import java.util.Vector; + +/** + * ASN.1 <code>SET</code> and <code>SET OF</code> constructs. + * <p> + * Note: This does not know which syntax the set is! + * (The difference: ordering of SET elements or not ordering.) + * <p> + * DER form is always definite form length fields, while + * BER support uses indefinite form. + * <p> + * The CER form support does not exist. + * <p> + * <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> + * <h4>8.12 Encoding of a set-of value</h4> + * <b>8.12.1</b> The encoding of a set-of value shall be constructed. + * <p> + * <b>8.12.2</b> The text of 8.10.2 applies: + * <i>The contents octets shall consist of zero, + * one or more complete encodings of data values from the type listed in + * the ASN.1 definition.</i> + * <p> + * <b>8.12.3</b> The order of data values need not be preserved by + * the encoding and subsequent decoding. + * + * <h3>9: Canonical encoding rules</h3> + * <h4>9.1 Length forms</h4> + * If the encoding is constructed, it shall employ the indefinite length form. + * If the encoding is primitive, it shall include the fewest length octets necessary. + * [Contrast with 8.1.3.2 b).] + * <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>10.1 Length forms</h4> + * The definite form of length encoding shall be used, + * encoded in the minimum number of octets. + * [Contrast with 8.1.3.2 b).] + * <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. + * <h4>11.6 Set-of components </h4> + * <p> + * The encodings of the component values of a set-of value + * shall appear in ascending order, the encodings being compared + * as octet strings with the shorter components being padded at + * their trailing end with 0-octets. + * <blockquote> + * NOTE — The padding octets are for comparison purposes only + * and do not appear in the encodings. + * </blockquote> + */ +public abstract class ASN1Set + extends ASN1Primitive +{ + private Vector set = new Vector(); + private boolean isSorted = false; + + /** + * return an ASN1Set from the given object. + * + * @param obj the object we want converted. + * @exception IllegalArgumentException if the object cannot be converted. + * @return an ASN1Set instance, or null. + */ + public static ASN1Set getInstance( + Object obj) + { + if (obj == null || obj instanceof ASN1Set) + { + return (ASN1Set)obj; + } + else if (obj instanceof ASN1SetParser) + { + return ASN1Set.getInstance(((ASN1SetParser)obj).toASN1Primitive()); + } + else if (obj instanceof byte[]) + { + try + { + return ASN1Set.getInstance(ASN1Primitive.fromByteArray((byte[])obj)); + } + catch (IOException e) + { + throw new IllegalArgumentException("failed to construct set from byte[]: " + e.getMessage()); + } + } + else if (obj instanceof ASN1Encodable) + { + ASN1Primitive primitive = ((ASN1Encodable)obj).toASN1Primitive(); + + if (primitive instanceof ASN1Set) + { + return (ASN1Set)primitive; + } + } + + throw new IllegalArgumentException("unknown object in getInstance: " + obj.getClass().getName()); + } + + /** + * Return an ASN1 set from a tagged object. There is a special + * case here, if an object appears to have been explicitly tagged on + * reading but we were expecting it to be implicitly tagged in the + * normal course of events it indicates that we lost the surrounding + * set - so we need to add it back (this will happen if the tagged + * object is a sequence that contains other sequences). If you are + * dealing with implicitly tagged sets you really <b>should</b> + * be using this method. + * + * @param obj the tagged object. + * @param explicit true if the object is meant to be explicitly tagged + * false otherwise. + * @exception IllegalArgumentException if the tagged object cannot + * be converted. + * @return an ASN1Set instance. + */ + public static ASN1Set getInstance( + ASN1TaggedObject obj, + boolean explicit) + { + if (explicit) + { + if (!obj.isExplicit()) + { + throw new IllegalArgumentException("object implicit - explicit expected."); + } + + return (ASN1Set)obj.getObject(); + } + else + { + // + // constructed object which appears to be explicitly tagged + // and it's really implicit means we have to add the + // surrounding set. + // + if (obj.isExplicit()) + { + if (obj instanceof BERTaggedObject) + { + return new BERSet(obj.getObject()); + } + else + { + return new DLSet(obj.getObject()); + } + } + else + { + if (obj.getObject() instanceof ASN1Set) + { + return (ASN1Set)obj.getObject(); + } + + // + // in this case the parser returns a sequence, convert it + // into a set. + // + if (obj.getObject() instanceof ASN1Sequence) + { + ASN1Sequence s = (ASN1Sequence)obj.getObject(); + + if (obj instanceof BERTaggedObject) + { + return new BERSet(s.toArray()); + } + else + { + return new DLSet(s.toArray()); + } + } + } + } + + throw new IllegalArgumentException("unknown object in getInstance: " + obj.getClass().getName()); + } + + protected ASN1Set() + { + } + + /** + * create a sequence containing one object + * @param obj object to be added to the SET. + */ + protected ASN1Set( + ASN1Encodable obj) + { + set.addElement(obj); + } + + /** + * create a sequence containing a vector of objects. + * @param v a vector of objects to make up the SET. + * @param doSort true if should be sorted DER style, false otherwise. + */ + protected ASN1Set( + ASN1EncodableVector v, + boolean doSort) + { + for (int i = 0; i != v.size(); i++) + { + set.addElement(v.get(i)); + } + + if (doSort) + { + this.sort(); + } + } + + /** + * create a sequence containing a vector of objects. + */ + protected ASN1Set( + ASN1Encodable[] array, + boolean doSort) + { + for (int i = 0; i != array.length; i++) + { + set.addElement(array[i]); + } + + if (doSort) + { + this.sort(); + } + } + + public Enumeration getObjects() + { + return set.elements(); + } + + /** + * return the object at the set position indicated by index. + * + * @param index the set number (starting at zero) of the object + * @return the object at the set position indicated by index. + */ + public ASN1Encodable getObjectAt( + int index) + { + return (ASN1Encodable)set.elementAt(index); + } + + /** + * return the number of objects in this set. + * + * @return the number of objects in this set. + */ + public int size() + { + return set.size(); + } + + public ASN1Encodable[] toArray() + { + ASN1Encodable[] values = new ASN1Encodable[this.size()]; + + for (int i = 0; i != this.size(); i++) + { + values[i] = this.getObjectAt(i); + } + + return values; + } + + public ASN1SetParser parser() + { + final ASN1Set outer = this; + + return new ASN1SetParser() + { + private final int max = size(); + + private int index; + + public ASN1Encodable readObject() throws IOException + { + if (index == max) + { + return null; + } + + ASN1Encodable obj = getObjectAt(index++); + if (obj instanceof ASN1Sequence) + { + return ((ASN1Sequence)obj).parser(); + } + if (obj instanceof ASN1Set) + { + return ((ASN1Set)obj).parser(); + } + + return obj; + } + + public ASN1Primitive getLoadedObject() + { + return outer; + } + + public ASN1Primitive toASN1Primitive() + { + return outer; + } + }; + } + + public int hashCode() + { + Enumeration e = this.getObjects(); + int hashCode = size(); + + while (e.hasMoreElements()) + { + Object o = getNext(e); + hashCode *= 17; + + hashCode ^= o.hashCode(); + } + + return hashCode; + } + + /** + * Change current SET object to be encoded as {@link DERSet}. + * This is part of Distinguished Encoding Rules form serialization. + */ + ASN1Primitive toDERObject() + { + if (isSorted) + { + ASN1Set derSet = new DERSet(); + + derSet.set = this.set; + + return derSet; + } + else + { + Vector v = new Vector(); + + for (int i = 0; i != set.size(); i++) + { + v.addElement(set.elementAt(i)); + } + + ASN1Set derSet = new DERSet(); + + derSet.set = v; + + derSet.sort(); + + return derSet; + } + } + + /** + * Change current SET object to be encoded as {@link DLSet}. + * This is part of Direct Length form serialization. + */ + ASN1Primitive toDLObject() + { + ASN1Set derSet = new DLSet(); + + derSet.set = this.set; + + return derSet; + } + + boolean asn1Equals( + ASN1Primitive o) + { + if (!(o instanceof ASN1Set)) + { + return false; + } + + ASN1Set other = (ASN1Set)o; + + if (this.size() != other.size()) + { + return false; + } + + Enumeration s1 = this.getObjects(); + Enumeration s2 = other.getObjects(); + + while (s1.hasMoreElements()) + { + ASN1Encodable obj1 = getNext(s1); + ASN1Encodable obj2 = getNext(s2); + + ASN1Primitive o1 = obj1.toASN1Primitive(); + ASN1Primitive o2 = obj2.toASN1Primitive(); + + if (o1 == o2 || o1.equals(o2)) + { + continue; + } + + return false; + } + + return true; + } + + private ASN1Encodable getNext(Enumeration e) + { + ASN1Encodable encObj = (ASN1Encodable)e.nextElement(); + + // unfortunately null was allowed as a substitute for DER null + if (encObj == null) + { + return DERNull.INSTANCE; + } + + return encObj; + } + + /** + * return true if a <= b (arrays are assumed padded with zeros). + */ + private boolean lessThanOrEqual( + byte[] a, + byte[] b) + { + int len = Math.min(a.length, b.length); + for (int i = 0; i != len; ++i) + { + if (a[i] != b[i]) + { + return (a[i] & 0xff) < (b[i] & 0xff); + } + } + return len == a.length; + } + + private byte[] getEncoded( + ASN1Encodable obj) + { + ByteArrayOutputStream bOut = new ByteArrayOutputStream(); + ASN1OutputStream aOut = new ASN1OutputStream(bOut); + + try + { + aOut.writeObject(obj); + } + catch (IOException e) + { + throw new IllegalArgumentException("cannot encode object added to SET"); + } + + return bOut.toByteArray(); + } + + protected void sort() + { + if (!isSorted) + { + isSorted = true; + if (set.size() > 1) + { + boolean swapped = true; + int lastSwap = set.size() - 1; + + while (swapped) + { + int index = 0; + int swapIndex = 0; + byte[] a = getEncoded((ASN1Encodable)set.elementAt(0)); + + swapped = false; + + while (index != lastSwap) + { + byte[] b = getEncoded((ASN1Encodable)set.elementAt(index + 1)); + + if (lessThanOrEqual(a, b)) + { + a = b; + } + else + { + Object o = set.elementAt(index); + + set.setElementAt(set.elementAt(index + 1), index); + set.setElementAt(o, index + 1); + + swapped = true; + swapIndex = index; + } + + index++; + } + + lastSwap = swapIndex; + } + } + } + } + + boolean isConstructed() + { + return true; + } + + abstract void encode(ASN1OutputStream out) + throws IOException; + + public String toString() + { + return set.toString(); + } +} |