dervalue.java

来自「This is a resource based on j2me embedde」· Java 代码 · 共 933 行 · 第 1/2 页

            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
     *
     * @return the octet string held in this DER value
     */
    public byte[] getOctetString() throws IOException {
        byte[] bytes;

        if (tag != tag_OctetString && !isConstructed(tag_OctetString)) {
            throw new IOException(
                "DerValue.getOctetString, not an Octet String: " + tag);
        }
        bytes = new byte[length];
        if (buffer.read(bytes) != length) {
            throw new IOException("short read on DerValue buffer");
        }
        if (isConstructed()) {
            DerInputStream in = new DerInputStream(bytes);
            bytes = null;
            while (in.available() != 0) {
                bytes = append(bytes, in.getOctetString());
            }
        }
        return bytes;
    }

    /**
     * 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.
     *
     * @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.
     *
     * @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.
     *
     * @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.
     *
     * @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 the name component as a Java string, regardless of its
     * encoding restrictions (ASCII, T61, Printable, IA5, BMP, UTF8).
     */
    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();
        }
        /*
          IMPL_NOTE: Need encoder for UniversalString before it can be handled.
          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.
     * @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();
    }

    /**
     * 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
     *
     * @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(), "US_ASCII");
    }

    /**
     * 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
     *
     * @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(), "US_ASCII");
    }

    /**
     * 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.
     *
     * @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(), "UTF-8");
    }

    /**
     * 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(), "US_ASCII");
    }

    /**
     * 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.
     *
     * @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());
    }

    /**
     * Returns true iff the other object is a DER value which
     * is bitwise equal to this one.
     *
     * @param other the object being compared with this one
     */
    public boolean equals(Object other) {
        if (other instanceof DerValue) {
            return equals((DerValue)other);
        } else {
            return false;
        }
    }

    /**
     * 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 other the object being compared with this one
     */
    public boolean equals(DerValue other) {
        if (this == other) {
            return true;
        }
        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()
     */
    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.
     *
     * @return printable representation of the value
     */
    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.
     *
     * @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.
     */
    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.
     */
    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).
     */
    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 class the tag class type, one of UNIVERSAL, CONTEXT,
     *               APPLICATION or PRIVATE
     * @params form if true, the value is constructed, otherwise it
     * is primitive.
     * @params 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
     */
    public void resetTag(byte tag) {
        this.tag = tag;
    }

    /**
     * Returns a hashcode for this DerValue.
     *
     * @return a hashcode for this DerValue.
     */
    public int hashCode() {
        return toString().hashCode();
    }
}