syntax = "proto3";

package envoy.api.v2;

import "api/address.proto";
import "api/base.proto";
import "api/discovery.proto";
import "api/sds.proto";

import "google/api/annotations.proto";
import "google/protobuf/struct.proto";
import "google/protobuf/wrappers.proto";

import "validate/validate.proto";

// [#protodoc-title: Listeners and LDS]
// Listener :ref:`configuration overview <config_listeners>`

// The Envoy instance initiates an RPC at startup to discover a list of
// listeners. Updates are delivered via streaming from the LDS server and
// consist of a complete update of all listeners. Existing connections will be
// allowed to drain from listeners that are no longer present.
service ListenerDiscoveryService {
  rpc StreamListeners(stream DiscoveryRequest) returns (stream DiscoveryResponse) {
  }

  rpc FetchListeners(DiscoveryRequest) returns (DiscoveryResponse) {
    option (google.api.http) = {
      post: "/v2/discovery:listeners"
      body: "*"
    };
  }
}

message Listener {
  // The unique name by which this listener is known. If no name is provided,
  // Envoy will allocate an internal UUID for the listener. If the listener is to be dynamically
  // updated or removed via :ref:`LDS <config_listeners_lds>` a unique name must be provided.
  // By default, the maximum length of a listener's name is limited to 60 characters. This limit can
  // be increased by setting the :option:`--max-obj-name-len` command line argument to the desired
  // value.
  string name = 1;

  // The address that the listener should listen on. In general, the address must be unique, though
  // that is governed by the bind rules of the OS. E.g., multiple listeners can listen on port 0 on
  // Linux as the actual port will be allocated by the OS.
  Address address = 2 [(validate.rules).message.required = true];

  // A list of filter chains to consider for this listener. The
  // :ref:`FilterChain <envoy_api_msg_FilterChain>` with the most specific :ref:`FilterChainMatch
  // <envoy_api_msg_FilterChainMatch>` criteria is used on a connection.
  //
  // .. attention::
  //
  //   In the current version, multiple filter chains are supported **only** so that SNI can be
  //   configured. See the :ref:`FAQ entry <faq_how_to_setup_sni>` on how to configure SNI for more
  //   information. When multiple filter chains are configured, each filter chain must have an
  //   **identical** set of :ref:`filters <envoy_api_field_FilterChain.filters>`. If the filters
  //   differ, the configuration will fail to load. In the future, this limitation will be relaxed
  //   such that different filters can be used depending on which filter chain matches (based on SNI
  //   or some other parameter).
  repeated FilterChain filter_chains = 3 [(validate.rules).repeated .min_items = 1];

  // If a connection is redirected using *iptables*, the port on which the proxy
  // receives it might be different from the original destination address. When this flag is set to
  // true, the listener hands off redirected connections to the listener associated with the
  // original destination address. If there is no listener associated with the original destination
  // address, the connection is handled by the listener that receives it. Defaults to false.
  google.protobuf.BoolValue use_original_dst = 4;

  // Soft limit on size of the listener’s new connection read and write buffers.
  // If unspecified, an implementation defined default is applied (1MiB).
  google.protobuf.UInt32Value per_connection_buffer_limit_bytes = 5;

  // [#not-implemented-hide:] Listener metadata.
  Metadata metadata = 6;

  // [#not-implemented-hide:]
  message DeprecatedV1 {
    // Whether the listener should bind to the port. A listener that doesn’t
    // bind can only receive connections redirected from other listeners that
    // set use_original_dst parameter to true. Default is true.
    //
    // [V2-API-DIFF] This is deprecated in v2, all Listeners will bind to their
    // port. An additional filter chain must be created for every original
    // destination port this listener may redirect to in v2, with the original
    // port specified in the FilterChainMatch destination_port field.
    google.protobuf.BoolValue bind_to_port = 1;
  }

  // [#not-implemented-hide:]
  DeprecatedV1 deprecated_v1 = 7;

  enum DrainType {
    // Drain in response to calling /healthcheck/fail admin endpoint (along with the health check
    // filter), listener removal/modification, and hot restart.
    DEFAULT = 0;
    // Drain in response to listener removal/modification and hot restart. This setting does not
    // include /healthcheck/fail. This setting may be desirable if Envoy is hosting both ingress
    // and egress listeners.
    MODIFY_ONLY = 1;
  }

  // The type of draining to perform at a listener-wide level.
  DrainType drain_type = 8;
}

message Filter {
  // The name of the filter to instantiate. The name must match a supported
  // filter. The built-in filters are:
  //
  // [#comment:TODO(mattklein123): Auto generate the following list]
  // * :ref:`envoy.echo <config_network_filters_echo>`
  // * :ref:`envoy.http_connection_manager <config_http_conn_man>`
  // * :ref:`envoy.mongo_proxy <config_network_filters_mongo_proxy>`
  // * :ref:`envoy.redis_proxy <config_network_filters_redis_proxy>`
  // * :ref:`envoy.tcp_proxy <config_network_filters_tcp_proxy>`
  string name = 1 [(validate.rules).string.min_bytes = 1];

  // Filter specific configuration which depends on the filter being
  // instantiated. See the supported filters for further documentation.
  google.protobuf.Struct config = 2;

  // [#not-implemented-hide:]
  message DeprecatedV1 {
    string type = 1;
  }

  // [#not-implemented-hide:]
  DeprecatedV1 deprecated_v1 = 3;
}

// Specifies the match criteria for selecting a specific filter chain for a
// listener.
message FilterChainMatch {
  // If non-empty, the SNI domains to consider. May contain a wildcard prefix,
  // e.g. ``*.example.com``.
  //
  // .. attention::
  //
  //   See the :ref:`FAQ entry <faq_how_to_setup_sni>` on how to configure SNI for more
  //   information.
  repeated string sni_domains = 1;

  // If non-empty, an IP address and prefix length to match addresses when the
  // listener is bound to 0.0.0.0/:: or when use_original_dst is specified.
  // [#not-implemented-hide:]
  repeated CidrRange prefix_ranges = 3;

  // If non-empty, an IP address and suffix length to match addresses when the
  // listener is bound to 0.0.0.0/:: or when use_original_dst is specified.
  // [#not-implemented-hide:]
  string address_suffix = 4;

  // [#not-implemented-hide:]
  google.protobuf.UInt32Value suffix_len = 5;

  // The criteria is satisfied if the source IP address of the downstream
  // connection is contained in at least one of the specified subnets. If the
  // parameter is not specified or the list is empty, the source IP address is
  // ignored.
  // [#not-implemented-hide:]
  repeated CidrRange source_prefix_ranges = 6;

  // The criteria is satisfied if the source port of the downstream connection
  // is contained in at least one of the specified ports. If the parameter is
  // not specified, the source port is ignored.
  // [#not-implemented-hide:]
  repeated google.protobuf.UInt32Value source_ports = 7;

  // Optional destination port to consider when use_original_dst is set on the
  // listener in determining a filter chain match.
  // [#not-implemented-hide:]
  google.protobuf.UInt32Value destination_port = 8;
}

// A filter chain wraps a set of match criteria, an option TLS context, a set of filters, and
// various other parameters.
message FilterChain {
  // The criteria to use when matching a connection to this filter chain.
  FilterChainMatch filter_chain_match = 1;

  // The TLS context for this filter chain.
  DownstreamTlsContext tls_context = 2;

  // A list of individual network filters that make up the filter chain for
  // connections established with the listener. Order matters as the filters are
  // processed sequentially as connection events happen. Note: If the filter
  // list is empty, the connection will close by default.
  repeated Filter filters = 3;

  // Whether the listener should expect a PROXY protocol V1 header on new
  // connections. If this option is enabled, the listener will assume that that
  // remote address of the connection is the one specified in the header. Some
  // load balancers including the AWS ELB support this option. If the option is
  // absent or set to false, Envoy will use the physical peer address of the
  // connection as the remote address.
  google.protobuf.BoolValue use_proxy_proto = 4;

  // [#not-implemented-hide:] filter chain metadata.
  Metadata metadata = 5;

  // [#not-implemented-hide:] See base.TransportSocket description.
  TransportSocket transport_socket = 6;
}