/// <summary>Decode BER encoded variable binding. /// </summary> /// <param name="buffer">BER encoded buffer /// </param> /// <param name="offset">Offset in the data buffer from where to start decoding. Offset is /// passed by reference and will contain the offset of the byte immediately after the parsed /// variable binding. /// </param> /// <returns>Buffer position after the decoded value</returns> public override int decode(byte[] buffer, int offset) { int headerLength; byte asnType = ParseHeader(buffer, ref offset, out headerLength); if (asnType != Type) { throw new SnmpException(string.Format("Invalid ASN.1 type. Expected 0x{0:x2} received 0x{1:x2}", Type, asnType)); } // verify the length if ((buffer.Length - offset) < headerLength) { throw new OverflowException("Buffer underflow error"); } _oid = new Oid(); offset = _oid.decode(buffer, offset); int saveOffset = offset; // Look ahead in the header to see the data type we need to parse asnType = ParseHeader(buffer, ref saveOffset, out headerLength); _value = SnmpConstants.GetSyntaxObject(asnType); if (_value == null) { throw new SnmpDecodingException(String.Format("Invalid ASN.1 type encountered 0x{0:x2}. Unable to continue decoding.", asnType)); } offset = _value.decode(buffer, offset); return(offset); }
/// <summary> /// Return printable string in the format oid: value /// </summary> /// <returns>Format Vb string</returns> public override string ToString() { return(_oid.ToString() + ": (" + SnmpConstants.GetTypeName(_value.Type) + ") " + _value.ToString()); }