Class BaseColumnEncryptionPolicy<TKey>

This abstract class provides functionality to manage the column encryption metadata of encrypted columns. You can implement a custom ColumnEncryptionPolicy by inheriting this class and overriding EncryptWithKey(TKey, byte[]) and DecryptWithKey(TKey, byte[]).

Inheritance

object

BaseColumnEncryptionPolicy<TKey>

AesColumnEncryptionPolicy

Implements

IColumnEncryptionPolicy

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Cassandra

Assembly: Cassandra.dll

Syntax

public abstract class BaseColumnEncryptionPolicy<TKey> : IColumnEncryptionPolicy

Type Parameters

Name	Description
TKey	The type of the "key" object that is used by the implementations of this class. See an example of this in AesColumnEncryptionPolicy. This is only meant to provide some compile time type safety since the base interface works with the basic "object" type.

Methods

AddColumn(string, string, string, TKey, ColumnTypeCode)

Provide cryptography materials to be used when encrypting and/or decrypting data for the specified column.

Declaration

public virtual void AddColumn(string ks, string table, string col, TKey key, ColumnTypeCode typeCode)

Parameters

Type	Name	Description
string	ks
string	table
string	col
TKey	key
ColumnTypeCode	typeCode

Remarks

If the typeCode is 'map','list','set','udt','tuple' or 'custom' then you have to use the other overload (AddColumn(string, string, string, TKey, ColumnTypeCode, IColumnInfo)) so you can provide the IColumnInfo.

AddColumn(string, string, string, TKey, ColumnTypeCode, IColumnInfo)

Provide cryptography materials to be used when encrypted and/or decrypting data for the specified column.

Declaration

public virtual void AddColumn(string ks, string table, string col, TKey key, ColumnTypeCode typeCode, IColumnInfo columnTypeInfo)

Parameters

Type	Name	Description
string	ks
string	table
string	col
TKey	key
ColumnTypeCode	typeCode
IColumnInfo	columnTypeInfo

Remarks

This overload has an extra parameter (columnTypeInfo) which is used if the typeCode refers to a type that requires extra type information. E.g. collection types require information about the type of objects that the collection contains. This overload should only be used if the column is of type 'map', 'list', 'set', 'udt', 'tuple' or 'custom'.

Decrypt(object, byte[])

Decrypt the specified (encrypted) bytes using the cryptography materials. This method is used by the driver internally before providing the results to the application.

Declaration

public byte[] Decrypt(object key, byte[] encryptedBytes)

Parameters

Type	Name	Description
object	key
byte[]	encryptedBytes

Returns

Type	Description
byte[]	Decrypted data in a byte array.

DecryptWithKey(TKey, byte[])

Decrypts the provided encrypted byte array with the provided key (which was previously added with the AddColumn(string, string, string, TKey, ColumnTypeCode) method).

Declaration

public abstract byte[] DecryptWithKey(TKey key, byte[] encryptedBytes)

Parameters

Type	Name	Description
TKey	key	Key that was previously provided with AddColumn(string, string, string, TKey, ColumnTypeCode).
byte[]	encryptedBytes	Encrypted bytes read from the server.

Returns

Type	Description
byte[]	The decrypted bytes (i.e. serialized value) which will then be deserialized by the driver afterwards.

Remarks

Implement your column encryption policy decryption logic by overriding this method.

Encrypt(object, byte[])

Encrypt the specified bytes using the cryptography materials. This method is used by the driver internally before sending the parameters to the server.

Declaration

public byte[] Encrypt(object key, byte[] objBytes)

Parameters

Type	Name	Description
object	key
byte[]	objBytes

Returns

Type	Description
byte[]	Encrypted data in a byte array. The returned byte array can't be 'null' because 'blob' types don't allow 'null' values.

EncryptWithKey(TKey, byte[])

Encrypts the provided byte array (serialized value) with the provided key (which was previously added with the AddColumn(string, string, string, TKey, ColumnTypeCode) method).

Declaration

public abstract byte[] EncryptWithKey(TKey key, byte[] objBytes)

Parameters

Type	Name	Description
TKey	key	Key that was previously provided with AddColumn(string, string, string, TKey, ColumnTypeCode).
byte[]	objBytes	Serialized value as a byte array.

Returns

Type	Description
byte[]	The encrypted bytes.

Remarks

Implement your column encryption policy encryption logic by overriding this method.

GetColumnEncryptionMetadata(string, string, string)

Retrieves the cryptography materials for the specified column. If the column is not encrypted then it should return 'null'.

Declaration

public virtual ColumnEncryptionMetadata? GetColumnEncryptionMetadata(string ks, string table, string col)

Parameters

Type	Name	Description
string	ks	Keyspace of this encrypted column's table.
string	table	Table of this encrypted column.
string	col	Name of this encrypted column at schema level.

Returns

Type	Description
ColumnEncryptionMetadata?

Implements

IColumnEncryptionPolicy