[Gateway API v1.2] Implement GEP-3155 / BackendTLS

[guydc]

Description:

Scope:

• Gateway: BackendTLS
• BackendTLSPolicy: SubjectAltNames

Out-of-Scope:

• BackendTLSPolicy Options : this is implementation-specific, and EG currently uses a typed approach for TLS settings in CTP and EP. Can be left out.

[optional Relevant Links:]

• Add GEP-3155: Complete Backend mTLS Configuration kubernetes-sigs/gateway-api#3180
• https://gateway-api.sigs.k8s.io/geps/gep-3155

[alexwo]

/assign

[github-actions]

This issue has been automatically marked as stale because it has not had activity in the last 30 days.