### Class

# Gcr SecretExchange

#### Description [src]

    class Gcr.SecretExchange : GObject.Object
    {
      /* No available fields */
    }

Allows exchange of secrets between two processes on the same system without exposing those secrets to things like loggers, non-pageable memory etc.

This does not protect against active attacks like MITM attacks.

Each side creates a secret exchange object, and one of the sides calls `gcr_secret_exchange_begin()`. This creates a string, which should be passed to the other side. Each side passes the strings it receives into `gcr_secret_exchange_receive()`.

In order to send a reply (either with or without a secret) use `gcr_secret_exchange_send()`. A side must have successfully called `gcr_secret_exchange_receive()` before it can use `gcr_secret_exchange_send()`.

The secret exchange objects can be used for multiple iterations of the conversation, or for just one request/reply. The only limitation being that the initial request cannot contain a secret.

Caveat: Information about the approximate length (rounded up to the nearest 16 bytes) may be leaked. If this is considered inacceptable, do not use `GcrSecretExchange`.

#### Hierarchy

#### Ancestors

- GObject

#### Constructors

###### gcr_secret_exchange_new

Create a new secret exchange object.

#### Instance methods

###### gcr_secret_exchange_begin

Begin the secret exchange. The resulting string should be sent to the other side of the exchange. The other side should use `gcr_secret_exchange_receive()` to process the string.

###### gcr_secret_exchange_get_protocol

Will return `NULL` if no protocol was specified, and either `gcr_secret_exchange_begin()` or `gcr_secret_exchange_receive()` have not been called successfully.

###### gcr_secret_exchange_get_secret

Returns the last secret received. If no secret has yet been received this will return `NULL`. The string is owned by the `GcrSecretExchange` object and will be valid until the next time that `gcr_secret_exchange_receive()` is called on this object, or the object is destroyed.

###### gcr_secret_exchange_receive

Receive a string from the other side of secret exchange. This string will have been created by `gcr_secret_exchange_begin()` or `gcr_secret_exchange_send()`.

###### gcr_secret_exchange_send

Send a reply to the other side of the secret exchange, optionally sending a secret.

##### Methods inherited from GObject (43)

Please see GObject for a full list of methods.

#### Properties

###### Gcr.SecretExchange:protocol

The protocol being used for the exchange.

#### Signals

##### Signals inherited from GObject (1)

###### GObject::notify

The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.

#### Class structure

    struct GcrSecretExchangeClass {
      gboolean (* generate_exchange_key) (
        GcrSecretExchange* exchange,
        const gchar* scheme,
        guchar** public_key,
        gsize* n_public_key
      );
      gboolean (* derive_transport_key) (
        GcrSecretExchange* exchange,
        const guchar* peer,
        gsize n_peer
      );
      gboolean (* encrypt_transport_data) (
        GcrSecretExchange* exchange,
        GckAllocator allocator,
        const guchar* plain_text,
        gsize n_plain_text,
        guchar** parameter,
        gsize* n_parameter,
        guchar** cipher_text,
        gsize* n_cipher_text
      );
      gboolean (* decrypt_transport_data) (
        GcrSecretExchange* exchange,
        GckAllocator allocator,
        const guchar* cipher_text,
        gsize n_cipher_text,
        const guchar* parameter,
        gsize n_parameter,
        guchar** plain_text,
        gsize* n_plain_text
      );

    }

No description available.

###### Class members

`generate_exchange_key: gboolean (* generate_exchange_key) ( GcrSecretExchange* exchange, const gchar* scheme, guchar** public_key, gsize* n_public_key )`

  No description available.

`derive_transport_key: gboolean (* derive_transport_key) ( GcrSecretExchange* exchange, const guchar* peer, gsize n_peer )`

  No description available.

`encrypt_transport_data: gboolean (* encrypt_transport_data) ( GcrSecretExchange* exchange, GckAllocator allocator, const guchar* plain_text, gsize n_plain_text, guchar** parameter, gsize* n_parameter, guchar** cipher_text, gsize* n_cipher_text )`

  No description available.

`decrypt_transport_data: gboolean (* decrypt_transport_data) ( GcrSecretExchange* exchange, GckAllocator allocator, const guchar* cipher_text, gsize n_cipher_text, const guchar* parameter, gsize n_parameter, guchar** plain_text, gsize* n_plain_text )`

  No description available.

#### Virtual methods

###### Gcr.SecretExchangeClass.decrypt_transport_data

No description available.

###### Gcr.SecretExchangeClass.derive_transport_key

No description available.

###### Gcr.SecretExchangeClass.encrypt_transport_data

No description available.

###### Gcr.SecretExchangeClass.generate_exchange_key

No description available.