Cipher filter plugin

The cipher algorithm

A list of supported algorithms can be obtained by

    puts OpenSSL::Cipher.ciphers

Do we have to perform a base64 decode or encode?

If we are decrypting, base64 decode will be done before. If we are encrypting, base64 will be done after.

Cipher padding to use. Enables or disables padding.

By default encryption operations are padded using standard block padding and the padding is checked and removed when decrypting. If the pad parameter is zero then no padding is performed, the total amount of data encrypted or decrypted must then be a multiple of the block size or an error will occur.

See EVP_CIPHER_CTX_set_padding for further information.

We are using Openssl jRuby which uses default padding to PKCS5Padding If you want to change it, set this parameter. If you want to disable it, Set this parameter to 0

    filter { cipher { cipher_padding => 0 }}

Force an random IV to be used per encryption invocation and specify the length of the random IV that will be generated via:

OpenSSL::Random.random_bytes(int_length)

If iv_random_length is set, it takes precedence over any value set for "iv"

Enabling this will force the plugin to generate a unique random IV for each encryption call. This random IV will be prepended to the encrypted result bytes and then base64 encoded. On decryption "iv_random_length" must also be set to utilize this feature. Random IV’s are better than statically hardcoded IVs

For AES algorithms you can set this to a 16

    filter { cipher { iv_random_length => 16 }}

The key to use

"java.security.InvalidKeyException: Illegal key size: possibly you need to install Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files for your JRE"

Please read the following: https://github.com/jruby/jruby/wiki/UnlimitedStrengthCrypto

The character used to pad the key

The key size to pad

It depends of the cipher algorithm. If your key doesn’t need padding, don’t set this parameter

Example, for AES-128, we must have 16 char long key. AES-256 = 32 chars

    filter { cipher { key_size => 16 }

If this is set the internal Cipher instance will be re-used up to @max_cipher_reuse times before being reset() and re-created from scratch. This is an option for efficiency where lots of data is being encrypted and decrypted using this filter. This lets the filter avoid creating new Cipher instances over and over for each encrypt/decrypt operation.

This is optional, the default is no re-use of the Cipher instance and max_cipher_reuse = 1 by default

    filter { cipher { max_cipher_reuse => 1000 }}

Encrypting or decrypting some data

Valid values are encrypt or decrypt

The field to perform filter

Example, to use the @message field (default) :

    filter { cipher { source => "message" } }

The name of the container to put the result

Example, to place the result into crypt :

    filter { cipher { target => "crypt" } }

If this filter is successful, add any arbitrary fields to this event. Field names can be dynamic and include parts of the event using the %{field}.

Example:

    filter {
      cipher {
        add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
      }
    }

    # You can also add multiple fields at once:
    filter {
      cipher {
        add_field => {
          "foo_%{somefield}" => "Hello world, from %{host}"
          "new_field" => "new_static_value"
        }
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add field foo_hello if it is present, with the value above and the %{host} piece replaced with that value from the event. The second example would also add a hardcoded field.

If this filter is successful, add arbitrary tags to the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      cipher {
        add_tag => [ "foo_%{somefield}" ]
      }
    }

    # You can also add multiple tags at once:
    filter {
      cipher {
        add_tag => [ "foo_%{somefield}", "taggedy_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add a tag foo_hello (and the second example would of course add a taggedy_tag tag).

Disable or enable metric logging for this specific plugin instance. By default we record all the metrics we can, but you can disable metrics collection for a specific plugin.

Add a unique ID to the plugin configuration. If no ID is specified, Logstash will generate one. It is strongly recommended to set this ID in your configuration. This is particularly useful when you have two or more plugins of the same type, for example, if you have 2 cipher filters. Adding a named ID in this case will help in monitoring Logstash when using the monitoring APIs.

    filter {
      cipher {
        id => "ABC"
      }
    }

Call the filter flush method at regular interval. Optional.

If this filter is successful, remove arbitrary fields from this event. Fields names can be dynamic and include parts of the event using the %{field} Example:

    filter {
      cipher {
        remove_field => [ "foo_%{somefield}" ]
      }
    }

    # You can also remove multiple fields at once:
    filter {
      cipher {
        remove_field => [ "foo_%{somefield}", "my_extraneous_field" ]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the field with name foo_hello if it is present. The second example would remove an additional, non-dynamic field.

If this filter is successful, remove arbitrary tags from the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      cipher {
        remove_tag => [ "foo_%{somefield}" ]
      }
    }

    # You can also remove multiple tags at once:
    filter {
      cipher {
        remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the tag foo_hello if it is present. The second example would remove a sad, unwanted tag as well.