- CAP_SYS_ADMIN
- CAP_NET_ADMIN
- CAP_NET_RAW

## Ambient mode details

Fundamentally, this component is responsible for the following:

- Sets up redirection with newly-started (or newly-added, previously-started) application pods such that traffic from application pods is forwarded to the local node's ztunnel pod.

Note: there are still some cluster roles that may need to be fixed, most likely cluster permissions
will need to move to the security component.

## Everything is Optional

Each component in the new installer is optional. Users can install the component defined in the new installer,
use the equivalent component in `istio-system`, configured with the official installer, or use a different
version or implementation.

three main components:

- [MeshConfig](https://github.com/istio/api/blob/master/mesh/v1alpha1/config.proto) for runtime config consumed directly by Istio
control plane components.
- [Component configuration API](https://github.com/istio/api/blob/00671adacbea20f941cb20cce021bc63cbad1840/operator/v1alpha1/operator.proto#L42-L93), for managing

bin/protoc-gen-docs*
bin/testlinter
bin/envvarlinter
bin/istioctl
*.orig
# Avoid accidental istio.VERSION changes
istio.VERSION
LICENSES.txt
# Proxy generated proxy config in integration test
tests/integration/component/proxy/envoy.conf
**/var/run/secrets/
# Certs generated by testing
security/cmd/node_agent/na/cert_file
security/cmd/node_agent/na/pkey
# istioctl bash completion file
tools/istioctl.bash
vendor

# Ztunnel

This document provides an overview of the architecture and design decisions around Ztunnel, the node-proxy component in ambient mode.

## Background and motivation

Motivations to implement ztunnel generally came from two areas.

First, and most importantly, it serves as a means to implement the real goal: waypoints.

  // For example:
  //   - "/healthz" is legal
  //   - "/hea*" is illegal
  //   - "/hea" is legal but matches nothing
  //   - "/hea/*" also matches nothing
  //   - "/healthz/*" matches all per-component health checks.
  // "*" matches all non-resource urls. if it is present, it must be the only entry.
  // +listType=set
  // Required.
  repeated string nonResourceURLs = 6;
}

  // For example:
  //   - "/healthz" is legal
  //   - "/hea*" is illegal
  //   - "/hea" is legal but matches nothing
  //   - "/hea/*" also matches nothing
  //   - "/healthz/*" matches all per-component health checks.
  // "*" matches all non-resource urls. if it is present, it must be the only entry.
  // +listType=set
  // Required.
  repeated string nonResourceURLs = 6;
}

  // ResourceClaimStatus this ResourceHandle is embedded in.
  optional string driverName = 1;

  // Data contains the opaque data associated with this ResourceHandle. It is
  // set by the controller component of the resource driver whose name
  // matches the DriverName set in the ResourceClaimStatus this
  // ResourceHandle is embedded in. It is set at allocation time and is

}

// Information about the condition of a component.
message ComponentCondition {
  // Type of condition for a component.
  // Valid value: "Healthy"
  optional string type = 1;

  // Status of the condition for a component.
  // Valid values for "Healthy": "True", "False", or "Unknown".
  optional string status = 2;

  // Message about the condition for a component.
  // For example, information about a health check.

#### CRD Watcher

For watches against custom types (CRDs), we want to gracefully handle missing CRDs. Naively starting informers against the missing types would result in errors and blocking startup. Instead, we introduce a "CRD Watcher" component that watches the CRDs in the cluster to determine if they are available or not.

This is consumed in two ways:
* Some components just block on `watcher.WaitForCRD(...)` before doing the work they need.