sdk/fidl/fuchsia.net.dhcp/client.fidl - fuchsia - Git at Google

 // Copyright 2023 The Fuchsia Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 library fuchsia.net.dhcp;

 using fuchsia.net;
 using fuchsia.net.interfaces.admin;

 /// The maximum possible number of DNS servers that can be included in an
 /// acquired DHCP configuration.
 ///
 /// According to [RFC 2132 section
 /// 3.8](https://www.rfc-editor.org/rfc/rfc2132#section-3.8), the length of the
 /// DNS server list in bytes is represented in the protocol by an 8-bit unsigned
 /// integer:
 /// "[variable-length options have] a length octet following the tag octet. The
 /// value of the length octet does not include the two octets specifying the tag
 /// and length."
 /// 2^8 = 256, which divided by 4 bytes gives us 64 as an upper bound on the
 /// maximum possible number of DNS servers that can be included in an acquired
 /// DHCP configuration.
 const MAX_DNS_SERVERS uint8 = 64;

 /// The maximum possible number of routers that can be included in an acquired
 /// DHCP configuration.
 ///
 /// According to [RFC 2132 section
 /// 3.5](https://www.rfc-editor.org/rfc/rfc2132#section-3.5), the length of the
 /// routers list in bytes is represented in the protocol by an 8-bit unsigned
 /// integer:
 /// "[variable-length options have] a length octet following the tag octet. The
 /// value of the length octet does not include the two octets specifying the
 /// tag and length."
 /// 2^8 = 256, which divided by 4 bytes gives us 64 as an upper bound on the
 /// maximum possible number of routers that can be included in an acquired
 /// DHCP configuration.
 const MAX_ROUTERS uint8 = 64;

 /// Describes the configuration information the DHCP client requests from DHCP
 /// servers.
 type ConfigurationToRequest = table {
     /// Request a list of IP addresses for routers on the client's subnet,
     /// in order of preference.
     /// See [RFC 2132 section 3.5](https://www.rfc-editor.org/rfc/rfc2132#section-3.5).
     ///
     /// If not set, interpreted as false.
     1: routers bool;
     /// Request a list of available DNS servers.
     /// See [RFC 2132 section 3.8](https://www.rfc-editor.org/rfc/rfc2132#section-3.8).
     ///
     /// If not set, interpreted as false.
     2: dns_servers bool;
 };

 /// Provides a method to create new DHCP clients.
 @discoverable
 closed protocol ClientProvider {
     /// Provides a DHCPv4 client.
     ///
     /// + request `params` the parameters to create the client with.
     /// + request `request` grants control over the client.
     strict NewClient(resource struct {
         /// The ID of the interface the client runs on.
         interface_id fuchsia.net.InterfaceId;

         /// The parameters with which to create the DHCP client.
         /// If `configuration_to_request` is unset and `request_ip_address` is
         /// false, `request` is closed with terminal event `INVALID_PARAMS`.
         params @generated_name("NewClientParams") table {
             /// Parameters for describing the configuration information the DHCP
             /// client requests from DHCP servers.
             ///
             /// If not set, interpreted as empty (no configuration information
             /// is requested).
             1: configuration_to_request ConfigurationToRequest;

             /// Whether the client negotiates an IP address.
             ///
             /// If false or not set, the client asks only for local
             /// configuration parameters.
             /// See [RFC 2131 section 3.4](https://www.rfc-editor.org/rfc/rfc2131#section-3.4).
             2: request_ip_address bool;
         };
         request server_end:Client;
     });

     /// No-op method that allows checking for presence.
     ///
     /// It's not currently possible for a client with an optionally-provided
     /// protocol to check whether there's someone on the other end without
     /// making a FIDL call (https://fxbug.dev/42177573). This method provides a
     /// workaround by giving a client a method that it can call to check for
     /// liveness.
     ///
     /// TODO(https://fxbug.dev/42076541): Remove this once the DHCP out-of-stack
     /// client is always being used.
     @deprecated("For DHCP client migration only, see https://fxbug.dev/42076541 for details")
     strict CheckPresence() -> ();
 };

 /// Provides methods to watch for discovered network configurations and control
 /// the DHCP client discovering them.
 ///
 /// This protocol encodes the DHCP client's lifetime in both directions;
 /// the DHCP client remains alive iff both ends of the protocol are open. That
 /// is:
 ///
 /// - Closing the client end causes the DHCP client to be destroyed.
 /// - Observing a closure of the server end indicates the DHCP client no longer
 ///   exists.
 closed protocol Client {
     /// Returns acquired DHCP configuration.
     ///
     /// Yields a value whenever the client acquires new configuration. Notably,
     /// does not yield a value upon DHCP lease expiry; instead, expiry of the IP
     /// address is communicated via the `AddressStateProvider` (refer to
     /// documentation of `fuchsia.net.interfaces.admin/AddressStateProvider` for
     /// details). Non-address configuration does not expire, but is replaced by
     /// new configuration once a new DHCP lease is obtained.
     ///
     /// It is invalid to call this method while a previous call is pending.
     /// Doing so causes the server end of the protocol to be closed.
     ///
     /// - response `address` the assigned address. If set, the client has
     ///     acquired a new lease on an IP address. If not set, then either the
     ///     client has not requested an IP address (in which case this `Client`
     ///     instance has never yielded an address), or the client continues to
     ///     hold a lease on a previously-acquired IP address (whose lifetime is
     ///     updated via `AddressStateProvider`).
     /// - response `dns_servers` addresses of discovered DNS servers. If absent,
     ///     must be interpreted as empty (the client's configuration indicates
     ///     no DNS servers, even if previously-yielded configuration included
     ///     DNS servers).
     /// - response `routers` addresses of discovered routers on the client's
     ///     subnet, in descending order of preference according to the DHCP
     ///     server. If absent, must be interpreted as empty (the client's
     ///     configuration indicates no routers, even if previously-yielded
     ///     configuration included routers).
     strict WatchConfiguration() -> (resource table {
         1: address resource table {
             /// The assigned address and prefix length.
             1: address fuchsia.net.Ipv4AddressWithPrefix;
             /// The parameters of the address.
             2: address_parameters fuchsia.net.interfaces.admin.AddressParameters;
             /// Provides address assignment state and enables updating address
             /// properties; the DHCP client closes the client end if the address
             /// becomes invalid (its valid lifetime expires and Renew and Rebind
             /// have not succeeded).
             /// The server end can be closed with a terminal OnAddressRemoved
             /// value in order to signal to the DHCP client that an address is
             /// rejected (e.g. due to failing duplicate address detection).
             3: address_state_provider server_end:fuchsia.net.interfaces.admin.AddressStateProvider;
         };
         2: dns_servers vector<fuchsia.net.Ipv4Address>:MAX_DNS_SERVERS;
         3: routers vector<fuchsia.net.Ipv4Address>:MAX_ROUTERS;
     });

     /// Instructs the client to shut down gracefully (releasing any DHCP lease
     /// currently held). When the client is finished shutting down, it yields
     /// the `ClientExitReason::GRACEFUL_SHUTDOWN` `OnExit` event.
     strict Shutdown();

     /// Terminal event yielded by the server before the server end is closed.
     ///
     /// - response `reason` the reason the DHCP client was closed.
     strict -> OnExit(struct {
         reason @generated_name("ClientExitReason") strict enum {
             /// A client already exists on the interface.
             CLIENT_ALREADY_EXISTS_ON_INTERFACE = 1;

             /// More than one concurrent call to `WatchConfiguration` was made.
             WATCH_CONFIGURATION_ALREADY_PENDING = 2;

             /// The interface identified is invalid for acquiring configuration.
             INVALID_INTERFACE = 3;

             /// Invalid `NewClientParams` were provided.
             INVALID_PARAMS = 4;

             /// The network was, or became, unreachable over the interface
             /// provided to the DHCP client.
             NETWORK_UNREACHABLE = 5;

             /// The client was unable to open a socket.
             UNABLE_TO_OPEN_SOCKET = 6;

             /// Graceful shutdown was performed.
             GRACEFUL_SHUTDOWN = 7;

             /// An address acquired by this client was removed by a user.
             ADDRESS_REMOVED_BY_USER = 8;

             /// The `AddressStateProvider` for an address acquired by this
             /// client exited with an error (or without providing a reason for
             /// the address removal).
             ADDRESS_STATE_PROVIDER_ERROR = 9;
         };
     });
 };
	// Copyright 2023 The Fuchsia Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.
	library fuchsia.net.dhcp;

	using fuchsia.net;
	using fuchsia.net.interfaces.admin;

	/// The maximum possible number of DNS servers that can be included in an
	/// acquired DHCP configuration.
	///
	/// According to [RFC 2132 section
	/// 3.8](https://www.rfc-editor.org/rfc/rfc2132#section-3.8), the length of the
	/// DNS server list in bytes is represented in the protocol by an 8-bit unsigned
	/// integer:
	/// "[variable-length options have] a length octet following the tag octet. The
	/// value of the length octet does not include the two octets specifying the tag
	/// and length."
	/// 2^8 = 256, which divided by 4 bytes gives us 64 as an upper bound on the
	/// maximum possible number of DNS servers that can be included in an acquired
	/// DHCP configuration.
	const MAX_DNS_SERVERS uint8 = 64;

	/// The maximum possible number of routers that can be included in an acquired
	/// DHCP configuration.
	///
	/// According to [RFC 2132 section
	/// 3.5](https://www.rfc-editor.org/rfc/rfc2132#section-3.5), the length of the
	/// routers list in bytes is represented in the protocol by an 8-bit unsigned
	/// integer:
	/// "[variable-length options have] a length octet following the tag octet. The
	/// value of the length octet does not include the two octets specifying the
	/// tag and length."
	/// 2^8 = 256, which divided by 4 bytes gives us 64 as an upper bound on the
	/// maximum possible number of routers that can be included in an acquired
	/// DHCP configuration.
	const MAX_ROUTERS uint8 = 64;

	/// Describes the configuration information the DHCP client requests from DHCP
	/// servers.
	type ConfigurationToRequest = table {
	/// Request a list of IP addresses for routers on the client's subnet,
	/// in order of preference.
	/// See [RFC 2132 section 3.5](https://www.rfc-editor.org/rfc/rfc2132#section-3.5).
	///
	/// If not set, interpreted as false.
	1: routers bool;
	/// Request a list of available DNS servers.
	/// See [RFC 2132 section 3.8](https://www.rfc-editor.org/rfc/rfc2132#section-3.8).
	///
	/// If not set, interpreted as false.
	2: dns_servers bool;
	};

	/// Provides a method to create new DHCP clients.
	@discoverable
	closed protocol ClientProvider {
	/// Provides a DHCPv4 client.
	///
	/// + request `params` the parameters to create the client with.
	/// + request `request` grants control over the client.
	strict NewClient(resource struct {
	/// The ID of the interface the client runs on.
	interface_id fuchsia.net.InterfaceId;

	/// The parameters with which to create the DHCP client.
	/// If `configuration_to_request` is unset and `request_ip_address` is
	/// false, `request` is closed with terminal event `INVALID_PARAMS`.
	params @generated_name("NewClientParams") table {
	/// Parameters for describing the configuration information the DHCP
	/// client requests from DHCP servers.
	///
	/// If not set, interpreted as empty (no configuration information
	/// is requested).
	1: configuration_to_request ConfigurationToRequest;

	/// Whether the client negotiates an IP address.
	///
	/// If false or not set, the client asks only for local
	/// configuration parameters.
	/// See [RFC 2131 section 3.4](https://www.rfc-editor.org/rfc/rfc2131#section-3.4).
	2: request_ip_address bool;
	};
	request server_end:Client;
	});

	/// No-op method that allows checking for presence.
	///
	/// It's not currently possible for a client with an optionally-provided
	/// protocol to check whether there's someone on the other end without
	/// making a FIDL call (https://fxbug.dev/42177573). This method provides a
	/// workaround by giving a client a method that it can call to check for
	/// liveness.
	///
	/// TODO(https://fxbug.dev/42076541): Remove this once the DHCP out-of-stack
	/// client is always being used.
	@deprecated("For DHCP client migration only, see https://fxbug.dev/42076541 for details")
	strict CheckPresence() -> ();
	};

	/// Provides methods to watch for discovered network configurations and control
	/// the DHCP client discovering them.
	///
	/// This protocol encodes the DHCP client's lifetime in both directions;
	/// the DHCP client remains alive iff both ends of the protocol are open. That
	/// is:
	///
	/// - Closing the client end causes the DHCP client to be destroyed.
	/// - Observing a closure of the server end indicates the DHCP client no longer
	/// exists.
	closed protocol Client {
	/// Returns acquired DHCP configuration.
	///
	/// Yields a value whenever the client acquires new configuration. Notably,
	/// does not yield a value upon DHCP lease expiry; instead, expiry of the IP
	/// address is communicated via the `AddressStateProvider` (refer to
	/// documentation of `fuchsia.net.interfaces.admin/AddressStateProvider` for
	/// details). Non-address configuration does not expire, but is replaced by
	/// new configuration once a new DHCP lease is obtained.
	///
	/// It is invalid to call this method while a previous call is pending.
	/// Doing so causes the server end of the protocol to be closed.
	///
	/// - response `address` the assigned address. If set, the client has
	/// acquired a new lease on an IP address. If not set, then either the
	/// client has not requested an IP address (in which case this `Client`
	/// instance has never yielded an address), or the client continues to
	/// hold a lease on a previously-acquired IP address (whose lifetime is
	/// updated via `AddressStateProvider`).
	/// - response `dns_servers` addresses of discovered DNS servers. If absent,
	/// must be interpreted as empty (the client's configuration indicates
	/// no DNS servers, even if previously-yielded configuration included
	/// DNS servers).
	/// - response `routers` addresses of discovered routers on the client's
	/// subnet, in descending order of preference according to the DHCP
	/// server. If absent, must be interpreted as empty (the client's
	/// configuration indicates no routers, even if previously-yielded
	/// configuration included routers).
	strict WatchConfiguration() -> (resource table {
	1: address resource table {
	/// The assigned address and prefix length.
	1: address fuchsia.net.Ipv4AddressWithPrefix;
	/// The parameters of the address.
	2: address_parameters fuchsia.net.interfaces.admin.AddressParameters;
	/// Provides address assignment state and enables updating address
	/// properties; the DHCP client closes the client end if the address
	/// becomes invalid (its valid lifetime expires and Renew and Rebind
	/// have not succeeded).
	/// The server end can be closed with a terminal OnAddressRemoved
	/// value in order to signal to the DHCP client that an address is
	/// rejected (e.g. due to failing duplicate address detection).
	3: address_state_provider server_end:fuchsia.net.interfaces.admin.AddressStateProvider;
	};
	2: dns_servers vector<fuchsia.net.Ipv4Address>:MAX_DNS_SERVERS;
	3: routers vector<fuchsia.net.Ipv4Address>:MAX_ROUTERS;
	});

	/// Instructs the client to shut down gracefully (releasing any DHCP lease
	/// currently held). When the client is finished shutting down, it yields
	/// the `ClientExitReason::GRACEFUL_SHUTDOWN` `OnExit` event.
	strict Shutdown();

	/// Terminal event yielded by the server before the server end is closed.
	///
	/// - response `reason` the reason the DHCP client was closed.
	strict -> OnExit(struct {
	reason @generated_name("ClientExitReason") strict enum {
	/// A client already exists on the interface.
	CLIENT_ALREADY_EXISTS_ON_INTERFACE = 1;

	/// More than one concurrent call to `WatchConfiguration` was made.
	WATCH_CONFIGURATION_ALREADY_PENDING = 2;

	/// The interface identified is invalid for acquiring configuration.
	INVALID_INTERFACE = 3;

	/// Invalid `NewClientParams` were provided.
	INVALID_PARAMS = 4;

	/// The network was, or became, unreachable over the interface
	/// provided to the DHCP client.
	NETWORK_UNREACHABLE = 5;

	/// The client was unable to open a socket.
	UNABLE_TO_OPEN_SOCKET = 6;

	/// Graceful shutdown was performed.
	GRACEFUL_SHUTDOWN = 7;

	/// An address acquired by this client was removed by a user.
	ADDRESS_REMOVED_BY_USER = 8;

	/// The `AddressStateProvider` for an address acquired by this
	/// client exited with an error (or without providing a reason for
	/// the address removal).
	ADDRESS_STATE_PROVIDER_ERROR = 9;
	};
	});
	};