java/11 : java.base/sun/security/util/DerValue.java

DerValue
https://openjdk.java.net/
GPLv2 + Classpath Exception
Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/**
 * Copyright (c) 1996, 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.security.util;

import java.io.*;
import java.math.BigInteger;
import java.util.Date;

Represents a single DER-encoded value.  DER encoding rules are a subset
of the "Basic" Encoding Rules (BER), but they only support a single way
("Definite" encoding) to encode any given value.
All DER-encoded data are triples {type, length, data}.  This
class represents such tagged values as they have been read (or constructed),
and provides structured access to the encoded data.
At this time, this class supports only a subset of the types of DER
data encodings which are defined.  That subset is sufficient for parsing
most X.509 certificates, and working with selected additional formats
(such as PKCS #10 certificate requests, and some kinds of PKCS #7 data).
A note with respect to T61/Teletex strings: From RFC 1617, section 4.1.3
and RFC 5280, section 8, we assume that this kind of string will contain
ISO-8859-1 characters only.
Author: David Brownell, Amit Kapoor, Hemma Prafullchandra/**
 * Represents a single DER-encoded value.  DER encoding rules are a subset
 * of the "Basic" Encoding Rules (BER), but they only support a single way
 * ("Definite" encoding) to encode any given value.
 *
 * <P>All DER-encoded data are triples <em>{type, length, data}</em>.  This
 * class represents such tagged values as they have been read (or constructed),
 * and provides structured access to the encoded data.
 *
 * <P>At this time, this class supports only a subset of the types of DER
 * data encodings which are defined.  That subset is sufficient for parsing
 * most X.509 certificates, and working with selected additional formats
 * (such as PKCS #10 certificate requests, and some kinds of PKCS #7 data).
 *
 * A note with respect to T61/Teletex strings: From RFC 1617, section 4.1.3
 * and RFC 5280, section 8, we assume that this kind of string will contain
 * ISO-8859-1 characters only.
 *
 *
 * @author David Brownell
 * @author Amit Kapoor
 * @author Hemma Prafullchandra
 */
public class DerValue {
    The tag class types /** The tag class types */
    public static final byte TAG_UNIVERSAL = (byte)0x000;
    public static final byte TAG_APPLICATION = (byte)0x040;
    public static final byte TAG_CONTEXT = (byte)0x080;
    public static final byte TAG_PRIVATE = (byte)0x0c0;

    The DER tag of the value; one of the tag_ constants. /** The DER tag of the value; one of the tag_ constants. */
    public byte                 tag;

    protected DerInputBuffer    buffer;

    The DER-encoded data of the value, never null
/**
     * The DER-encoded data of the value, never null
     */
    public final DerInputStream data;

    private int                 length;

    /*
     * The type starts at the first byte of the encoding, and
     * is one of these tag_* values.  That may be all the type
     * data that is needed.
     */

    /*
     * These tags are the "universal" tags ... they mean the same
     * in all contexts.  (Mask with 0x1f -- five bits.)
     */

    Tag value indicating an ASN.1 "BOOLEAN" value. /** Tag value indicating an ASN.1 "BOOLEAN" value. */
    public static final byte    tag_Boolean = 0x01;

    Tag value indicating an ASN.1 "INTEGER" value. /** Tag value indicating an ASN.1 "INTEGER" value. */
    public static final byte    tag_Integer = 0x02;

    Tag value indicating an ASN.1 "BIT STRING" value. /** Tag value indicating an ASN.1 "BIT STRING" value. */
    public static final byte    tag_BitString = 0x03;

    Tag value indicating an ASN.1 "OCTET STRING" value. /** Tag value indicating an ASN.1 "OCTET STRING" value. */
    public static final byte    tag_OctetString = 0x04;

    Tag value indicating an ASN.1 "NULL" value. /** Tag value indicating an ASN.1 "NULL" value. */
    public static final byte    tag_Null = 0x05;

    Tag value indicating an ASN.1 "OBJECT IDENTIFIER" value. /** Tag value indicating an ASN.1 "OBJECT IDENTIFIER" value. */
    public static final byte    tag_ObjectId = 0x06;

    Tag value including an ASN.1 "ENUMERATED" value /** Tag value including an ASN.1 "ENUMERATED" value */
    public static final byte    tag_Enumerated = 0x0A;

    Tag value indicating an ASN.1 "UTF8String" value. /** Tag value indicating an ASN.1 "UTF8String" value. */
    public static final byte    tag_UTF8String = 0x0C;

    Tag value including a "printable" string /** Tag value including a "printable" string */
    public static final byte    tag_PrintableString = 0x13;

    Tag value including a "teletype" string /** Tag value including a "teletype" string */
    public static final byte    tag_T61String = 0x14;

    Tag value including an ASCII string /** Tag value including an ASCII string */
    public static final byte    tag_IA5String = 0x16;

    Tag value indicating an ASN.1 "UTCTime" value. /** Tag value indicating an ASN.1 "UTCTime" value. */
    public static final byte    tag_UtcTime = 0x17;

    Tag value indicating an ASN.1 "GeneralizedTime" value. /** Tag value indicating an ASN.1 "GeneralizedTime" value. */
    public static final byte    tag_GeneralizedTime = 0x18;

    Tag value indicating an ASN.1 "GenerallString" value. /** Tag value indicating an ASN.1 "GenerallString" value. */
    public static final byte    tag_GeneralString = 0x1B;

    Tag value indicating an ASN.1 "UniversalString" value. /** Tag value indicating an ASN.1 "UniversalString" value. */
    public static final byte    tag_UniversalString = 0x1C;

    Tag value indicating an ASN.1 "BMPString" value. /** Tag value indicating an ASN.1 "BMPString" value. */
    public static final byte    tag_BMPString = 0x1E;

    // CONSTRUCTED seq/set

    Tag value indicating an ASN.1
"SEQUENCE" (zero to N elements, order is significant).
/**
     * Tag value indicating an ASN.1
     * "SEQUENCE" (zero to N elements, order is significant).
     */
    public static final byte    tag_Sequence = 0x30;

    Tag value indicating an ASN.1
"SEQUENCE OF" (one to N elements, order is significant).
/**
     * Tag value indicating an ASN.1
     * "SEQUENCE OF" (one to N elements, order is significant).
     */
    public static final byte    tag_SequenceOf = 0x30;

    Tag value indicating an ASN.1
"SET" (zero to N members, order does not matter).
/**
     * Tag value indicating an ASN.1
     * "SET" (zero to N members, order does not matter).
     */
    public static final byte    tag_Set = 0x31;

    Tag value indicating an ASN.1
"SET OF" (one to N members, order does not matter).
/**
     * Tag value indicating an ASN.1
     * "SET OF" (one to N members, order does not matter).
     */
    public static final byte    tag_SetOf = 0x31;

    /*
     * These values are the high order bits for the other kinds of tags.
     */

    Returns true if the tag class is UNIVERSAL.
/**
     * Returns true if the tag class is UNIVERSAL.
     */
    public boolean isUniversal()      { return ((tag & 0x0c0) == 0x000); }

    Returns true if the tag class is APPLICATION.
/**
     * Returns true if the tag class is APPLICATION.
     */
    public boolean isApplication()    { return ((tag & 0x0c0) == 0x040); }

    Returns true iff the CONTEXT SPECIFIC bit is set in the type tag.
This is associated with the ASN.1 "DEFINED BY" syntax.
/**
     * Returns true iff the CONTEXT SPECIFIC bit is set in the type tag.
     * This is associated with the ASN.1 "DEFINED BY" syntax.
     */
    public boolean isContextSpecific() { return ((tag & 0x0c0) == 0x080); }

    Returns true iff the CONTEXT SPECIFIC TAG matches the passed tag.
/**
     * Returns true iff the CONTEXT SPECIFIC TAG matches the passed tag.
     */
    public boolean isContextSpecific(byte cntxtTag) {
        if (!isContextSpecific()) {
            return false;
        }
        return ((tag & 0x01f) == cntxtTag);
    }

    boolean isPrivate()        { return ((tag & 0x0c0) == 0x0c0); }

    Returns true iff the CONSTRUCTED bit is set in the type tag. /** Returns true iff the CONSTRUCTED bit is set in the type tag. */
    public boolean isConstructed()    { return ((tag & 0x020) == 0x020); }

    Returns true iff the CONSTRUCTED TAG matches the passed tag.
/**
     * Returns true iff the CONSTRUCTED TAG matches the passed tag.
     */
    public boolean isConstructed(byte constructedTag) {
        if (!isConstructed()) {
            return false;
        }
        return ((tag & 0x01f) == constructedTag);
    }

    Creates a PrintableString or UTF8string DER value from a string
/**
     * Creates a PrintableString or UTF8string DER value from a string
     */
    public DerValue(String value) throws IOException {
        boolean isPrintableString = true;
        for (int i = 0; i < value.length(); i++) {
            if (!isPrintableStringChar(value.charAt(i))) {
                isPrintableString = false;
                break;
            }
        }

        data = init(isPrintableString ? tag_PrintableString : tag_UTF8String, value);
    }

    Creates a string type DER value from a String object
Params: stringTag – the tag for the DER value to create
value – the String object to use for the DER value/**
     * Creates a string type DER value from a String object
     * @param stringTag the tag for the DER value to create
     * @param value the String object to use for the DER value
     */
    public DerValue(byte stringTag, String value) throws IOException {
        data = init(stringTag, value);
    }

    // Creates a DerValue from a tag and some DER-encoded data w/ additional
    // arg to control whether DER checks are enforced.
    DerValue(byte tag, byte[] data, boolean allowBER) {
        this.tag = tag;
        buffer = new DerInputBuffer(data.clone(), allowBER);
        length = data.length;
        this.data = new DerInputStream(buffer);
        this.data.mark(Integer.MAX_VALUE);
    }

    Creates a DerValue from a tag and some DER-encoded data.
Params: tag – the DER type tag
data – the DER-encoded data/**
     * Creates a DerValue from a tag and some DER-encoded data.
     *
     * @param tag the DER type tag
     * @param data the DER-encoded data
     */
    public DerValue(byte tag, byte[] data) {
        this(tag, data, true);
    }

    /*
     * package private
     */
    DerValue(DerInputBuffer in) throws IOException {

        // XXX must also parse BER-encoded constructed
        // values such as sequences, sets...
        tag = (byte)in.read();
        byte lenByte = (byte)in.read();
        length = DerInputStream.getLength(lenByte, in);
        if (length == -1) {  // indefinite length encoding found
            DerInputBuffer inbuf = in.dup();
            int readLen = inbuf.available();
            int offset = 2;     // for tag and length bytes
            byte[] indefData = new byte[readLen + offset];
            indefData[0] = tag;
            indefData[1] = lenByte;
            DataInputStream dis = new DataInputStream(inbuf);
            dis.readFully(indefData, offset, readLen);
            dis.close();
            DerIndefLenConverter derIn = new DerIndefLenConverter();
            inbuf = new DerInputBuffer(derIn.convert(indefData), in.allowBER);
            if (tag != inbuf.read())
                throw new IOException
                        ("Indefinite length encoding not supported");
            length = DerInputStream.getDefiniteLength(inbuf);
            buffer = inbuf.dup();
            buffer.truncate(length);
            data = new DerInputStream(buffer);
            // indefinite form is encoded by sending a length field with a
            // length of 0. - i.e. [1000|0000].
            // the object is ended by sending two zero bytes.
            in.skip(length + offset);
        } else {

            buffer = in.dup();
            buffer.truncate(length);
            data = new DerInputStream(buffer);

            in.skip(length);
        }
    }

    // Get an ASN.1/DER encoded datum from a buffer w/ additional
    // arg to control whether DER checks are enforced.
    DerValue(byte[] buf, boolean allowBER) throws IOException {
        data = init(true, new ByteArrayInputStream(buf), allowBER);
    }

    Get an ASN.1/DER encoded datum from a buffer.  The
entire buffer must hold exactly one datum, including
its tag and length.
Params: buf – buffer holding a single DER-encoded datum./**
     * Get an ASN.1/DER encoded datum from a buffer.  The
     * entire buffer must hold exactly one datum, including
     * its tag and length.
     *
     * @param buf buffer holding a single DER-encoded datum.
     */
    public DerValue(byte[] buf) throws IOException {
        this(buf, true);
    }

    // Get an ASN.1/DER encoded datum from part of a buffer w/ additional
    // arg to control whether DER checks are enforced.
    DerValue(byte[] buf, int offset, int len, boolean allowBER)
        throws IOException {
        data = init(true, new ByteArrayInputStream(buf, offset, len), allowBER);
    }

    Get an ASN.1/DER encoded datum from part of a buffer.
That part of the buffer must hold exactly one datum, including
its tag and length.
Params: buf – the buffer
offset – start point of the single DER-encoded dataum
len – how many bytes are in the encoded datum/**
     * Get an ASN.1/DER encoded datum from part of a buffer.
     * That part of the buffer must hold exactly one datum, including
     * its tag and length.
     *
     * @param buf the buffer
     * @param offset start point of the single DER-encoded dataum
     * @param len how many bytes are in the encoded datum
     */
    public DerValue(byte[] buf, int offset, int len) throws IOException {
        this(buf, offset, len, true);
    }

    // Get an ASN1/DER encoded datum from an input stream w/ additional
    // arg to control whether DER checks are enforced.
    DerValue(InputStream in, boolean allowBER) throws IOException {
        data = init(false, in, allowBER);
    }

    Get an ASN1/DER encoded datum from an input stream.  The
stream may have additional data following the encoded datum.
In case of indefinite length encoded datum, the input stream
must hold only one datum.
Params: in – the input stream holding a single DER datum,
 which may be followed by additional data/**
     * Get an ASN1/DER encoded datum from an input stream.  The
     * stream may have additional data following the encoded datum.
     * In case of indefinite length encoded datum, the input stream
     * must hold only one datum.
     *
     * @param in the input stream holding a single DER datum,
     *  which may be followed by additional data
     */
    public DerValue(InputStream in) throws IOException {
        this(in, true);
    }

    private DerInputStream init(byte stringTag, String value)
        throws IOException {
        String enc = null;

        tag = stringTag;

        switch (stringTag) {
        case tag_PrintableString:
        case tag_IA5String:
        case tag_GeneralString:
            enc = "ASCII";
            break;
        case tag_T61String:
            enc = "ISO-8859-1";
            break;
        case tag_BMPString:
            enc = "UnicodeBigUnmarked";
            break;
        case tag_UTF8String:
            enc = "UTF8";
            break;
            // TBD: Need encoder for UniversalString before it can
            // be handled.
        default:
            throw new IllegalArgumentException("Unsupported DER string type");
        }

        byte[] buf = value.getBytes(enc);
        length = buf.length;
        buffer = new DerInputBuffer(buf, true);
        DerInputStream result = new DerInputStream(buffer);
        result.mark(Integer.MAX_VALUE);
        return result;
    }

    /*
     * helper routine
     */
    private DerInputStream init(boolean fullyBuffered, InputStream in,
        boolean allowBER) throws IOException {

        tag = (byte)in.read();
        byte lenByte = (byte)in.read();
        length = DerInputStream.getLength(lenByte, in);
        if (length == -1) { // indefinite length encoding found
            int readLen = in.available();
            int offset = 2;     // for tag and length bytes
            byte[] indefData = new byte[readLen + offset];
            indefData[0] = tag;
            indefData[1] = lenByte;
            DataInputStream dis = new DataInputStream(in);
            dis.readFully(indefData, offset, readLen);
            dis.close();
            DerIndefLenConverter derIn = new DerIndefLenConverter();
            in = new ByteArrayInputStream(derIn.convert(indefData));
            if (tag != in.read())
                throw new IOException
                        ("Indefinite length encoding not supported");
            length = DerInputStream.getDefiniteLength(in);
        }

        if (fullyBuffered && in.available() != length)
            throw new IOException("extra data given to DerValue constructor");

        byte[] bytes = IOUtils.readExactlyNBytes(in, length);

        buffer = new DerInputBuffer(bytes, allowBER);
        return new DerInputStream(buffer);
    }

    Encode an ASN1/DER encoded datum onto a DER output stream.
/**
     * Encode an ASN1/DER encoded datum onto a DER output stream.
     */
    public void encode(DerOutputStream out)
    throws IOException {
        out.write(tag);
        out.putLength(length);
        // XXX yeech, excess copies ... DerInputBuffer.write(OutStream)
        if (length > 0) {
            byte[] value = new byte[length];
            // always synchronized on data
            synchronized (data) {
                buffer.reset();
                if (buffer.read(value) != length) {
                    throw new IOException("short DER value read (encode)");
                }
                out.write(value);
            }
        }
    }

    public final DerInputStream getData() {
        return data;
    }

    public final byte getTag() {
        return tag;
    }

    Returns an ASN.1 BOOLEAN
Returns: the boolean held in this DER value/**
     * Returns an ASN.1 BOOLEAN
     *
     * @return the boolean held in this DER value
     */
    public boolean getBoolean() throws IOException {
        if (tag != tag_Boolean) {
            throw new IOException("DerValue.getBoolean, not a BOOLEAN " + tag);
        }
        if (length != 1) {
            throw new IOException("DerValue.getBoolean, invalid length "
                                        + length);
        }
        if (buffer.read() != 0) {
            return true;
        }
        return false;
    }

    Returns an ASN.1 OBJECT IDENTIFIER.
Returns: the OID held in this DER value/**
     * Returns an ASN.1 OBJECT IDENTIFIER.
     *
     * @return the OID held in this DER value
     */
    public ObjectIdentifier getOID() throws IOException {
        if (tag != tag_ObjectId)
            throw new IOException("DerValue.getOID, not an OID " + tag);
        return new ObjectIdentifier(buffer);
    }

    private byte[] append(byte[] a, byte[] b) {
        if (a == null)
            return b;

        byte[] ret = new byte[a.length + b.length];
        System.arraycopy(a, 0, ret, 0, a.length);
        System.arraycopy(b, 0, ret, a.length, b.length);

        return ret;
    }

    Returns an ASN.1 OCTET STRING
Returns: the octet string held in this DER value/**
     * Returns an ASN.1 OCTET STRING
     *
     * @return the octet string held in this DER value
     */
    public byte[] getOctetString() throws IOException {

        if (tag != tag_OctetString && !isConstructed(tag_OctetString)) {
            throw new IOException(
                "DerValue.getOctetString, not an Octet String: " + tag);
        }
        // Note: do not attempt to call buffer.read(bytes) at all. There's a
        // known bug that it returns -1 instead of 0.
        if (length == 0) {
            return new byte[0];
        }

        // Only allocate the array if there are enough bytes available.
        // This only works for ByteArrayInputStream.
        // The assignment below ensures that buffer has the required type.
        ByteArrayInputStream arrayInput = buffer;
        if (arrayInput.available() < length) {
            throw new IOException("short read on DerValue buffer");
        }
        byte[] bytes = new byte[length];
        arrayInput.read(bytes);

        if (isConstructed()) {
            DerInputStream in = new DerInputStream(bytes, 0, bytes.length,
                buffer.allowBER);
            bytes = null;
            while (in.available() != 0) {
                bytes = append(bytes, in.getOctetString());
            }
        }
        return bytes;
    }

    Returns an ASN.1 INTEGER value as an integer.
Returns: the integer held in this DER value./**
     * Returns an ASN.1 INTEGER value as an integer.
     *
     * @return the integer held in this DER value.
     */
    public int getInteger() throws IOException {
        if (tag != tag_Integer) {
            throw new IOException("DerValue.getInteger, not an int " + tag);
        }
        return buffer.getInteger(data.available());
    }

    Returns an ASN.1 INTEGER value as a BigInteger.
Returns: the integer held in this DER value as a BigInteger./**
     * Returns an ASN.1 INTEGER value as a BigInteger.
     *
     * @return the integer held in this DER value as a BigInteger.
     */
    public BigInteger getBigInteger() throws IOException {
        if (tag != tag_Integer)
            throw new IOException("DerValue.getBigInteger, not an int " + tag);
        return buffer.getBigInteger(data.available(), false);
    }

    Returns an ASN.1 INTEGER value as a positive BigInteger.
This is just to deal with implementations that incorrectly encode
some values as negative.
Returns: the integer held in this DER value as a BigInteger./**
     * Returns an ASN.1 INTEGER value as a positive BigInteger.
     * This is just to deal with implementations that incorrectly encode
     * some values as negative.
     *
     * @return the integer held in this DER value as a BigInteger.
     */
    public BigInteger getPositiveBigInteger() throws IOException {
        if (tag != tag_Integer)
            throw new IOException("DerValue.getBigInteger, not an int " + tag);
        return buffer.getBigInteger(data.available(), true);
    }

    Returns an ASN.1 ENUMERATED value.
Returns: the integer held in this DER value./**
     * Returns an ASN.1 ENUMERATED value.
     *
     * @return the integer held in this DER value.
     */
    public int getEnumerated() throws IOException {
        if (tag != tag_Enumerated) {
            throw new IOException("DerValue.getEnumerated, incorrect tag: "
                                  + tag);
        }
        return buffer.getInteger(data.available());
    }

    Returns an ASN.1 BIT STRING value.  The bit string must be byte-aligned.
Returns: the bit string held in this value/**
     * Returns an ASN.1 BIT STRING value.  The bit string must be byte-aligned.
     *
     * @return the bit string held in this value
     */
    public byte[] getBitString() throws IOException {
        if (tag != tag_BitString)
            throw new IOException(
                "DerValue.getBitString, not a bit string " + tag);

        return buffer.getBitString();
    }

    Returns an ASN.1 BIT STRING value that need not be byte-aligned.
Returns: a BitArray representing the bit string held in this value/**
     * Returns an ASN.1 BIT STRING value that need not be byte-aligned.
     *
     * @return a BitArray representing the bit string held in this value
     */
    public BitArray getUnalignedBitString() throws IOException {
        if (tag != tag_BitString)
            throw new IOException(
                "DerValue.getBitString, not a bit string " + tag);

        return buffer.getUnalignedBitString();
    }

    Returns the name component as a Java string, regardless of its
encoding restrictions (ASCII, T61, Printable, IA5, BMP, UTF8).
/**
     * Returns the name component as a Java string, regardless of its
     * encoding restrictions (ASCII, T61, Printable, IA5, BMP, UTF8).
     */
    // TBD: Need encoder for UniversalString before it can be handled.
    public String getAsString() throws IOException {
        if (tag == tag_UTF8String)
            return getUTF8String();
        else if (tag == tag_PrintableString)
            return getPrintableString();
        else if (tag == tag_T61String)
            return getT61String();
        else if (tag == tag_IA5String)
            return getIA5String();
        /*
          else if (tag == tag_UniversalString)
          return getUniversalString();
        */
        else if (tag == tag_BMPString)
            return getBMPString();
        else if (tag == tag_GeneralString)
            return getGeneralString();
        else
            return null;
    }

    Returns an ASN.1 BIT STRING value, with the tag assumed implicit
based on the parameter.  The bit string must be byte-aligned.
Params: tagImplicit – if true, the tag is assumed implicit.
Returns: the bit string held in this value/**
     * Returns an ASN.1 BIT STRING value, with the tag assumed implicit
     * based on the parameter.  The bit string must be byte-aligned.
     *
     * @param tagImplicit if true, the tag is assumed implicit.
     * @return the bit string held in this value
     */
    public byte[] getBitString(boolean tagImplicit) throws IOException {
        if (!tagImplicit) {
            if (tag != tag_BitString)
                throw new IOException("DerValue.getBitString, not a bit string "
                                       + tag);
            }
        return buffer.getBitString();
    }

    Returns an ASN.1 BIT STRING value, with the tag assumed implicit
based on the parameter.  The bit string need not be byte-aligned.
Params: tagImplicit – if true, the tag is assumed implicit.
Returns: the bit string held in this value/**
     * Returns an ASN.1 BIT STRING value, with the tag assumed implicit
     * based on the parameter.  The bit string need not be byte-aligned.
     *
     * @param tagImplicit if true, the tag is assumed implicit.
     * @return the bit string held in this value
     */
    public BitArray getUnalignedBitString(boolean tagImplicit)
    throws IOException {
        if (!tagImplicit) {
            if (tag != tag_BitString)
                throw new IOException("DerValue.getBitString, not a bit string "
                                       + tag);
            }
        return buffer.getUnalignedBitString();
    }

    Helper routine to return all the bytes contained in the
DerInputStream associated with this object.
/**
     * Helper routine to return all the bytes contained in the
     * DerInputStream associated with this object.
     */
    public byte[] getDataBytes() throws IOException {
        byte[] retVal = new byte[length];
        synchronized (data) {
            data.reset();
            data.getBytes(retVal);
        }
        return retVal;
    }

    Returns an ASN.1 STRING value
Returns: the printable string held in this value/**
     * Returns an ASN.1 STRING value
     *
     * @return the printable string held in this value
     */
    public String getPrintableString()
    throws IOException {
        if (tag != tag_PrintableString)
            throw new IOException(
                "DerValue.getPrintableString, not a string " + tag);

        return new String(getDataBytes(), "ASCII");
    }

    Returns an ASN.1 T61 (Teletype) STRING value
Returns: the teletype string held in this value/**
     * Returns an ASN.1 T61 (Teletype) STRING value
     *
     * @return the teletype string held in this value
     */
    public String getT61String() throws IOException {
        if (tag != tag_T61String)
            throw new IOException(
                "DerValue.getT61String, not T61 " + tag);

        return new String(getDataBytes(), "ISO-8859-1");
    }

    Returns an ASN.1 IA5 (ASCII) STRING value
Returns: the ASCII string held in this value/**
     * Returns an ASN.1 IA5 (ASCII) STRING value
     *
     * @return the ASCII string held in this value
     */
    public String getIA5String() throws IOException {
        if (tag != tag_IA5String)
            throw new IOException(
                "DerValue.getIA5String, not IA5 " + tag);

        return new String(getDataBytes(), "ASCII");
    }

    Returns the ASN.1 BMP (Unicode) STRING value as a Java string.
Returns: a string corresponding to the encoded BMPString held in
this value/**
     * Returns the ASN.1 BMP (Unicode) STRING value as a Java string.
     *
     * @return a string corresponding to the encoded BMPString held in
     * this value
     */
    public String getBMPString() throws IOException {
        if (tag != tag_BMPString)
            throw new IOException(
                "DerValue.getBMPString, not BMP " + tag);

        // BMPString is the same as Unicode in big endian, unmarked
        // format.
        return new String(getDataBytes(), "UnicodeBigUnmarked");
    }

    Returns the ASN.1 UTF-8 STRING value as a Java String.
Returns: a string corresponding to the encoded UTF8String held in
this value/**
     * Returns the ASN.1 UTF-8 STRING value as a Java String.
     *
     * @return a string corresponding to the encoded UTF8String held in
     * this value
     */
    public String getUTF8String() throws IOException {
        if (tag != tag_UTF8String)
            throw new IOException(
                "DerValue.getUTF8String, not UTF-8 " + tag);

        return new String(getDataBytes(), "UTF8");
    }

    Returns the ASN.1 GENERAL STRING value as a Java String.
Returns: a string corresponding to the encoded GeneralString held in
this value/**
     * Returns the ASN.1 GENERAL STRING value as a Java String.
     *
     * @return a string corresponding to the encoded GeneralString held in
     * this value
     */
    public String getGeneralString() throws IOException {
        if (tag != tag_GeneralString)
            throw new IOException(
                "DerValue.getGeneralString, not GeneralString " + tag);

        return new String(getDataBytes(), "ASCII");
    }

    Returns a Date if the DerValue is UtcTime.
Returns: the Date held in this DER value/**
     * Returns a Date if the DerValue is UtcTime.
     *
     * @return the Date held in this DER value
     */
    public Date getUTCTime() throws IOException {
        if (tag != tag_UtcTime) {
            throw new IOException("DerValue.getUTCTime, not a UtcTime: " + tag);
        }
        return buffer.getUTCTime(data.available());
    }

    Returns a Date if the DerValue is GeneralizedTime.
Returns: the Date held in this DER value/**
     * Returns a Date if the DerValue is GeneralizedTime.
     *
     * @return the Date held in this DER value
     */
    public Date getGeneralizedTime() throws IOException {
        if (tag != tag_GeneralizedTime) {
            throw new IOException(
                "DerValue.getGeneralizedTime, not a GeneralizedTime: " + tag);
        }
        return buffer.getGeneralizedTime(data.available());
    }

    Bitwise equality comparison.  DER encoded values have a single
encoding, so that bitwise equality of the encoded values is an
efficient way to establish equivalence of the unencoded values.
Params: o – the object being compared with this one/**
     * Bitwise equality comparison.  DER encoded values have a single
     * encoding, so that bitwise equality of the encoded values is an
     * efficient way to establish equivalence of the unencoded values.
     *
     * @param o the object being compared with this one
     */
    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof DerValue)) {
            return false;
        }
        DerValue other = (DerValue) o;
        if (tag != other.tag) {
            return false;
        }
        if (data == other.data) {
            return true;
        }

        // make sure the order of lock is always consistent to avoid a deadlock
        return (System.identityHashCode(this.data)
                > System.identityHashCode(other.data)) ?
                doEquals(this, other):
                doEquals(other, this);
    }

    Helper for public method equals()
/**
     * Helper for public method equals()
     */
    private static boolean doEquals(DerValue d1, DerValue d2) {
        synchronized (d1.data) {
            synchronized (d2.data) {
                d1.data.reset();
                d2.data.reset();
                return d1.buffer.equals(d2.buffer);
            }
        }
    }

    Returns a printable representation of the value.
Returns: printable representation of the value/**
     * Returns a printable representation of the value.
     *
     * @return printable representation of the value
     */
    @Override
    public String toString() {
        try {

            String str = getAsString();
            if (str != null)
                return "\"" + str + "\"";
            if (tag == tag_Null)
                return "[DerValue, null]";
            if (tag == tag_ObjectId)
                return "OID." + getOID();

            // integers
            else
                return "[DerValue, tag = " + tag
                        + ", length = " + length + "]";
        } catch (IOException e) {
            throw new IllegalArgumentException("misformatted DER value");
        }
    }

    Returns a DER-encoded value, such that if it's passed to the
DerValue constructor, a value equivalent to "this" is returned.
Returns: DER-encoded value, including tag and length./**
     * Returns a DER-encoded value, such that if it's passed to the
     * DerValue constructor, a value equivalent to "this" is returned.
     *
     * @return DER-encoded value, including tag and length.
     */
    public byte[] toByteArray() throws IOException {
        DerOutputStream out = new DerOutputStream();

        encode(out);
        data.reset();
        return out.toByteArray();
    }

    For "set" and "sequence" types, this function may be used
to return a DER stream of the members of the set or sequence.
This operation is not supported for primitive types such as
integers or bit strings.
/**
     * For "set" and "sequence" types, this function may be used
     * to return a DER stream of the members of the set or sequence.
     * This operation is not supported for primitive types such as
     * integers or bit strings.
     */
    public DerInputStream toDerInputStream() throws IOException {
        if (tag == tag_Sequence || tag == tag_Set)
            return new DerInputStream(buffer);
        throw new IOException("toDerInputStream rejects tag type " + tag);
    }

    Get the length of the encoded value.
/**
     * Get the length of the encoded value.
     */
    public int length() {
        return length;
    }

    Determine if a character is one of the permissible characters for
PrintableString:
A-Z, a-z, 0-9, space, apostrophe (39), left and right parentheses,
plus sign, comma, hyphen, period, slash, colon, equals sign,
and question mark.
Characters that are *not* allowed in PrintableString include
exclamation point, quotation mark, number sign, dollar sign,
percent sign, ampersand, asterisk, semicolon, less than sign,
greater than sign, at sign, left and right square brackets,
backslash, circumflex (94), underscore, back quote (96),
left and right curly brackets, vertical line, tilde,
and the control codes (0-31 and 127).
This list is based on X.680 (the ASN.1 spec).
/**
     * Determine if a character is one of the permissible characters for
     * PrintableString:
     * A-Z, a-z, 0-9, space, apostrophe (39), left and right parentheses,
     * plus sign, comma, hyphen, period, slash, colon, equals sign,
     * and question mark.
     *
     * Characters that are *not* allowed in PrintableString include
     * exclamation point, quotation mark, number sign, dollar sign,
     * percent sign, ampersand, asterisk, semicolon, less than sign,
     * greater than sign, at sign, left and right square brackets,
     * backslash, circumflex (94), underscore, back quote (96),
     * left and right curly brackets, vertical line, tilde,
     * and the control codes (0-31 and 127).
     *
     * This list is based on X.680 (the ASN.1 spec).
     */
    public static boolean isPrintableStringChar(char ch) {
        if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') ||
            (ch >= '0' && ch <= '9')) {
            return true;
        } else {
            switch (ch) {
                case ' ':       /* space */
                case '\'':      /* apostrophe */
                case '(':       /* left paren */
                case ')':       /* right paren */
                case '+':       /* plus */
                case ',':       /* comma */
                case '-':       /* hyphen */
                case '.':       /* period */
                case '/':       /* slash */
                case ':':       /* colon */
                case '=':       /* equals */
                case '?':       /* question mark */
                    return true;
                default:
                    return false;
            }
        }
    }

    Create the tag of the attribute.
Params: tagClass – the tag class type, one of UNIVERSAL, CONTEXT,
              APPLICATION or PRIVATE
form – if true, the value is constructed, otherwise it
is primitive.
val – the tag value/**
     * Create the tag of the attribute.
     *
     * @param tagClass the tag class type, one of UNIVERSAL, CONTEXT,
     *               APPLICATION or PRIVATE
     * @param form if true, the value is constructed, otherwise it
     * is primitive.
     * @param val the tag value
     */
    public static byte createTag(byte tagClass, boolean form, byte val) {
        byte tag = (byte)(tagClass | val);
        if (form) {
            tag |= (byte)0x20;
        }
        return (tag);
    }

    Set the tag of the attribute. Commonly used to reset the
tag value used for IMPLICIT encodings.
Params: tag – the tag value/**
     * Set the tag of the attribute. Commonly used to reset the
     * tag value used for IMPLICIT encodings.
     *
     * @param tag the tag value
     */
    public void resetTag(byte tag) {
        this.tag = tag;
    }

    Returns a hashcode for this DerValue.
Returns: a hashcode for this DerValue./**
     * Returns a hashcode for this DerValue.
     *
     * @return a hashcode for this DerValue.
     */
    @Override
    public int hashCode() {
        return toString().hashCode();
    }
}
Params:	tagImplicit – if true, the tag is assumed implicit.
Returns:	the bit string held in this value
/

java/ 11/ java.base/sun/security/util/DerValue.java
