/******************************************************************************* * This file is part of OpenNMS(R). * * Copyright (C) 2011 The OpenNMS Group, Inc. * OpenNMS(R) is Copyright (C) 1999-2011 The OpenNMS Group, Inc. * * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc. * * OpenNMS(R) is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published * by the Free Software Foundation, either version 3 of the License, * or (at your option) any later version. * * OpenNMS(R) 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 for more details. * * You should have received a copy of the GNU General Public License * along with OpenNMS(R). If not, see: * http://www.gnu.org/licenses/ * * For more information contact: * OpenNMS(R) Licensing <license@opennms.org> * http://www.opennms.org/ * http://www.opennms.com/ *******************************************************************************/ package org.opennms.protocols.snmp.asn1; import java.math.BigInteger; /** * The AsnEncoder interface defines the contract that objects for * encoding/decoding ASN.1 SNMP values must fulfill. The encoder must be able to * encode and decode integers (unsigned and signed), object identifier, strings, * and null values. To support the SNMPv2 the AsnEncoder class must also support * encoding/decoding 64-bit integers. Currently the AsnEncoder interface only * supports SNMPv1 types. * * @author <a href="mailto:weave@oculan.com>Brian Weaver </a> */ public interface AsnEncoder { /** * * The buildLength() method is used to encode an ASN.1 length into the * specified byte buffer. The encoding used is dependant on the implementor * of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnLength * The length to be encoded. * * @return Returns the new offset for the next encoding routine. If the * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildLength(byte[] buf, int startOffset, int asnLength) throws AsnEncodingException; /** * * The parseLength() method is used to decode an ASN.1 length from the * specified buffer. The encoding used is depandant on the implemetor of the * interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset and the * decoded length. The first object is an Integer object and * contains the new offset for the next object in buf. The second * object is an Integer and contains the actual decoded length. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseLength(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildHeader() method is used to encode an ASN.1 header into the * specified byte buffer. The encoding used is dependant on the implementor * of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param asnLength * The length to be encoded. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildHeader(byte[] buf, int startOffset, byte asnType, int asnLength) throws AsnEncodingException; /** * * The parseHeader() method is used to decode an ASN.1 header from the * specified buffer. The encoding used is depandant on the implemetor of the * interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset, ASN.1 type, * and decoded length. The first object is an Integer object and * contains the new offset for the next object in buf. The second * object is a Byte object that represents the decoded ASN.1 Type. * The third object is an Integer and contains the actual decoded * length. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseHeader(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildInteger32() method is used to encode an ASN.1 32-bit signed * integer into the specified byte buffer. The encoding used is dependant on * the implementor of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param asnInt32 * The 32-bit signed integer to encode. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildInteger32(byte[] buf, int startOffset, byte asnType, int asnInt32) throws AsnEncodingException; /** * * The parseInteger32() method is used to decode an ASN.1 32-bit signed * integer from the specified buffer. The encoding used is depandant on the * implemetor of the interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset, ASN.1 type, * and value. The first object is an Integer object and contains the * new offset for the next object in buf. The second object is a * Byte object that represents the decoded ASN.1 Type. The third * object is an Integer and contains the actual decoded value. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseInteger32(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildUInteger32() method is used to encode an ASN.1 32-bit unsigned * integer into the specified byte buffer. The encoding used is dependant on * the implementor of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param asnUInt32 * The 32-bit unsigned integer to encode. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildUInteger32(byte[] buf, int startOffset, byte asnType, long asnUInt32) throws AsnEncodingException; /** * * The parseUInteger32() method is used to decode an ASN.1 32-bit unsigned * integer from the specified buffer. The encoding used is depandant on the * implemetor of the interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset, ASN.1 type, * and value. The first object is an Integer object and contains the * new offset for the next object in buf. The second object is a * Byte object that represents the decoded ASN.1 Type. The third * object is a Long object and contains the actual decoded value. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseUInteger32(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildUInteger64() method is used to encode an ASN.1 64-bit unsigned * integer into the specified byte buffer. The encoding used is dependant on * the implementor of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param asnUInt64 * The 64-bit unsigned integer to encode. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildUInteger64(byte[] buf, int startOffset, byte asnType, BigInteger asnUInt64) throws AsnEncodingException; /** * * The parseUInteger64() method is used to decode an ASN.1 64-bit unsigned * integer from the specified buffer. The encoding used is depandant on the * implemetor of the interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset, ASN.1 type, * and value. The first object is an Integer object and contains the * new offset for the next object in buf. The second object is a * Byte object that represents the decoded ASN.1 Type. The third * object is a BigInteger object and contains the actual decoded * value. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseUInteger64(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildNull() method is used to encode an ASN.1 NULL value into the * specified byte buffer. The encoding used is dependant on the implementor * of the interface. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildNull(byte[] buf, int startOffset, byte asnType) throws AsnEncodingException; /** * * The parseNull() method is used to decode an ASN.1 Null value from the * specified buffer. The encoding used is depandant on the implemetor of the * interface. Since there is no "null" value only the new offset and ASN.1 * type are returned. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset and the * ASN.1 type. The first object is an Integer object and contains * the new offset for the next object in buf. The second object is a * Byte object that represents the decoded ASN.1 Type. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseNull(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildString() method is used to encode an ASN.1 string value into the * specified byte buffer. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param opaque * An array of bytes to encode into the string. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildString(byte[] buf, int startOffset, byte asnType, byte[] opaque) throws AsnEncodingException; /** * * The parseString() method is used to decode an ASN.1 opaque string from * the specified buffer. The encoding used is depandant on the implemetor of * the interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset and ASN.1 * type, and byte array. The first object is an Integer object and * contains the new offset for the next object in buf. The second * object is a Byte object that represents the decoded ASN.1 Type. * The third object is an array of primitive bytes. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseString(byte[] buf, int startOffset) throws AsnDecodingException; /** * * The buildObjectId() method is used to encode an ASN.1 object id value * into the specified byte buffer. * * @param buf * The output buffer of encoded bytes. * @param startOffset * The offset from the start of the buffer where the method * should start writing the encoded data. * @param asnType * The ASN.1 type to place in the buffer * @param oids * An array of integers to encode. * * @return Returns the new offset for the next encoding routine. If * startOffset is subtracted from the return value then the length * of the encoded data can be determined. * * @exception AsnEncodingException * Thrown if an error occurs encoding the datatype. * */ public int buildObjectId(byte[] buf, int startOffset, byte asnType, int[] oids) throws AsnEncodingException; /** * * The parseObjectId() method is used to decode an ASN.1 Object Identifer * from the specified buffer. The encoding used is depandant on the * implemetor of the interface. * * @param buf * The input buffer * @param startOffset * The offset to start decoding in the buffer * * @return Returns an Object array that contains the new offset and ASN.1 * type, and ObjectId array. The first object is an Integer object * and contains the new offset for the next object in buf. The * second object is a Byte object that represents the decoded ASN.1 * Type. The third object is an array of primitive integers. * * @exception AsnDecodingException * Thrown if an error occurs decoding the buffer. */ public Object[] parseObjectId(byte[] buf, int startOffset) throws AsnDecodingException; }