BackendTLSPolicy.spec.validation

CACertificateRefs contains one or more references to Kubernetes objects that contain a PEM-encoded TLS CA certificate bundle, which is used to validate a TLS handshake between the Gateway and backend Pod. If CACertificateRefs is empty or unspecified, then WellKnownCACertificates must be specified. Only one of CACertificateRefs or WellKnownCACertificates may be specified, not both. If CACertificateRefs is empty or unspecified, the configuration for WellKnownCACertificates MUST be honored instead if supported by the implementation. A CACertificateRef is invalid if: * It refers to a resource that cannot be resolved (e.g., the referenced resource does not exist) or is misconfigured (e.g., a ConfigMap does not contain a key named `ca.crt`). In this case, the Reason must be set to `InvalidCACertificateRef` and the Message of the Condition must indicate which reference is invalid and why. * It refers to an unknown or unsupported kind of resource. In this case, the Reason must be set to `InvalidKind` and the Message of the Condition must explain which kind of resource is unknown or unsupported. * It refers to a resource in another namespace. This may change in future spec updates. Implementations MAY choose to perform further validation of the certificate content (e.g., checking expiry or enforcing specific formats). In such cases, an implementation-specific Reason and Message must be set for the invalid reference. In all cases, the implementation MUST ensure the `ResolvedRefs` Condition on the BackendTLSPolicy is set to `status: False`, with a Reason and Message that indicate the cause of the error. Connections using an invalid CACertificateRef MUST fail, and the client MUST receive an HTTP 5xx error response. If ALL CACertificateRefs are invalid, the implementation MUST also ensure the `Accepted` Condition on the BackendTLSPolicy is set to `status: False`, with a Reason `NoValidCACertificate`. A single CACertificateRef to a Kubernetes ConfigMap kind has "Core" support. Implementations MAY choose to support attaching multiple certificates to a backend, but this behavior is implementation-specific. Support: Core - An optional single reference to a Kubernetes ConfigMap, with the CA certificate in a key named `ca.crt`. Support: Implementation-specific - More than one reference, other kinds of resources, or a single reference that includes multiple certificates.

• maxItems: 8
• x-kubernetes-list-type: "atomic"

Hostname is used for two purposes in the connection between Gateways and backends: 1. Hostname MUST be used as the SNI to connect to the backend (RFC 6066). 2. Hostname MUST be used for authentication and MUST match the certificate served by the matching backend, unless SubjectAltNames is specified. 3. If SubjectAltNames are specified, Hostname can be used for certificate selection but MUST NOT be used for authentication. If you want to use the value of the Hostname field for authentication, you MUST add it to the SubjectAltNames list. Support: Core

• minLength: 1
• maxLength: 253
• pattern: ^[a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*$

SubjectAltNames contains one or more Subject Alternative Names. When specified the certificate served from the backend MUST have at least one Subject Alternate Name matching one of the specified SubjectAltNames. Support: Extended

• maxItems: 5
• x-kubernetes-list-type: "atomic"

WellKnownCACertificates specifies whether a well-known set of CA certificates may be used in the TLS handshake between the gateway and backend pod. If WellKnownCACertificates is unspecified or empty (""), then CACertificateRefs must be specified with at least one entry for a valid configuration. Only one of CACertificateRefs or WellKnownCACertificates may be specified, not both. If an implementation does not support the WellKnownCACertificates field, or the supplied value is not recognized, the implementation MUST ensure the `Accepted` Condition on the BackendTLSPolicy is set to `status: False`, with a Reason `Invalid`. Valid values include: * "System" - indicates that well-known system CA certificates should be used. Implementations MAY define their own sets of CA certificates. Such definitions MUST use an implementation-specific, prefixed name, such as `mycompany.com/my-custom-ca-certificates`. Support: Implementation-specific

• minLength: 1
• maxLength: 253
• pattern: ^(System|([a-z0-9]([-a-z0-9]*[a-z0-9])?(\.[a-z0-9]([-a-z0-9]*[a-z0-9])?)*/([A-Za-z0-9][-A-Za-z0-9_.]{0,61})?[A-Za-z0-9]))$