/// <summary>
/// Get security enum as integer value.
/// </summary>
/// <param name="security">Security level.</param>
/// <returns>Integer value of security level.</returns>
private static int GetSecurityValue(Gurux.DLMS.Enums.Security security)
{
int value = 0;
switch (security)
{
case Gurux.DLMS.Enums.Security.None:
value = 0;
break;
case Gurux.DLMS.Enums.Security.Authentication:
value = 1;
break;
case Gurux.DLMS.Enums.Security.Encryption:
value = 2;
break;
case Gurux.DLMS.Enums.Security.AuthenticationEncryption:
value = 3;
break;
default:
throw new ArgumentOutOfRangeException("Invalid Security enum.");
}
return(value);
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="security">Used security level.</param>
/// <param name="encrypt"></param>
/// <param name="blockCipherKey"></param>
/// <param name="aad"></param>
/// <param name="iv"></param>
/// <param name="tag"></param>
public GXDLMSChipperingStream(Gurux.DLMS.Enums.Security security, bool encrypt, byte[] blockCipherKey, byte[] aad, byte[] iv, byte[] tag)
{
this.Security = security;
const int TagSize = 0x10;
this.Tag = tag;
if (this.Tag == null)//Tag size is 12 bytes.
{
this.Tag = new byte[12];
}
else if (this.Tag.Length != 12)
{
throw new ArgumentOutOfRangeException("Invalid tag.");
}
Encrypt = encrypt;
WorkingKey = GenerateKey(encrypt, blockCipherKey);
int bufLength = Encrypt ? BlockSize : (BlockSize + TagSize);
this.bufBlock = new byte[bufLength];
Aad = aad;
this.H = new byte[BlockSize];
ProcessBlock(H, 0, H, 0);
Init(H);
this.J0 = new byte[16];
Array.Copy(iv, 0, J0, 0, iv.Length);
this.J0[15] = 0x01;
this.S = GetGHash(Aad);
this.counter = (byte[])J0.Clone();
this.BytesRemaining = 0;
this.totalLength = 0;
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="tag">Command.</param>
/// <param name="security"></param>
/// <param name="invocationCounter">Invocation counter.</param>
/// <param name="systemTitle"></param>
/// <param name="blockCipherKey"></param>
/// <param name="authenticationKey"></param>
public AesGcmParameter(
byte tag,
Gurux.DLMS.Enums.Security security,
UInt32 invocationCounter,
byte[] systemTitle,
byte[] blockCipherKey,
byte[] authenticationKey)
{
Tag = tag;
Security = security;
InvocationCounter = invocationCounter;
SystemTitle = systemTitle;
BlockCipherKey = blockCipherKey;
AuthenticationKey = authenticationKey;
Type = CountType.Packet;
}
private static byte[] GetAuthenticatedData(Gurux.DLMS.Enums.Security security, byte[] AuthenticationKey, byte[] plainText)
{
if (security == Gurux.DLMS.Enums.Security.Authentication)
{
GXByteBuffer tmp2 = new GXByteBuffer();
tmp2.SetUInt8((byte)security);
tmp2.Set(AuthenticationKey);
tmp2.Set(plainText);
return(tmp2.Array());
}
else if (security == Gurux.DLMS.Enums.Security.Encryption)
{
return(AuthenticationKey);
}
else if (security == Gurux.DLMS.Enums.Security.AuthenticationEncryption)
{
GXByteBuffer tmp2 = new GXByteBuffer();
tmp2.SetUInt8((byte)security);
tmp2.Set(AuthenticationKey);
return(tmp2.Array());
}
return(null);
}
/// <summary>
/// Activates and strengthens the security policy.
/// </summary>
/// <param name="client">DLMS client that is used to generate action.</param>
/// <param name="security">New security level.</param>
/// <returns>Generated action.</returns>
public byte[][] Activate(GXDLMSClient client, Gurux.DLMS.Enums.Security security)
{
return(client.Method(this, 1, GetSecurityValue(security), DataType.Enum));
}
/// <summary>
/// Constructor.
/// </summary>
/// <param name="security">Used security level.</param>
/// <param name="encrypt"></param>
/// <param name="blockCipherKey"></param>
/// <param name="aad"></param>
/// <param name="iv"></param>
/// <param name="tag"></param>
public GXDLMSChipperingStream(Gurux.DLMS.Enums.Security security, bool encrypt, byte[] blockCipherKey, byte[] aad, byte[] iv, byte[] tag)
{
this.Security = security;
const int TagSize = 0x10;
this.Tag = tag;
if (this.Tag == null)//Tag size is 12 bytes.
{
this.Tag = new byte[12];
}
else if (this.Tag.Length != 12)
{
throw new ArgumentOutOfRangeException("Invalid tag.");
}
Encrypt = encrypt;
WorkingKey = GenerateKey(encrypt, blockCipherKey);
int bufLength = Encrypt ? BlockSize : (BlockSize + TagSize);
this.bufBlock = new byte[bufLength];
Aad = aad;
this.H = new byte[BlockSize];
ProcessBlock(H, 0, H, 0);
Init(H);
this.J0 = new byte[16];
Array.Copy(iv, 0, J0, 0, iv.Length);
this.J0[15] = 0x01;
this.S = GetGHash(Aad);
this.counter = (byte[])J0.Clone();
this.BytesRemaining = 0;
this.totalLength = 0;
}
