ingress-yubikey

This is a proof-of-concept highly experimental! Kubernetes Ingress Controller that terminates TLS using a certificate and key from the PIV smartcard applet on a YubiKey. This addresses a common complaint that Kubernetes Ingress controllers have cluster-wide access to secrets in order to retrieve TLS private keys. With a hardware-backed key, the private key never exists in application memory.

Usage

Check you have a working yubikey before deploying:

./ingress-yubikey validate

If not, you can set up the PIV applet like so:

ykman piv reset
ykman piv generate-key -m 010203040506070801020304050607080102030405060708 -P 123456 -a ECCP256 --pin-policy NEVER --touch-policy NEVER 9c 9c.pub
ykman piv generate-csr -s your-hostname.com 9c 9c.pub 9c.csr
# Sign the CSR, even with a publicly trusted CA!
ykman piv import-certificate 9c 9c.pem

ingress-yubikey watches for networking.k8s.io/v1 Ingress objects with their Ingress Class set to ingress-yubikey As the only goal is to terminate TLS, path rules are ignored, but TLS hosts are matched by parsing SNI.

For now, ingress-yubikey always uses the Digital Signature certificate in slot 9c. Insert an appropriately prepared YubiKey and run the ingress controller using the manifest in ./deploy as a guide. Volume mount the smartcard device appropriately.

PIN - protected keys

Again for now, the PIN for accessing the signing key can be provided with the flag --smartcard-pin or environment variable INGRESS_YUBIKEY_SMARTCARD_PIN.