"crypto/internal/fips140deps/byteorder" ) // We don't set the service indicator in this package but we delegate that to // the underlying functions because the TLS 1.3 KDF does not have a standard of // its own. // ExpandLabel implements HKDF-Expand-Label from RFC 8446, Section 7.1. func ExpandLabel[H fips140.Hash](hash func() H, secret []byte, label string, context []byte, length int) []byte { if len("tls13 ")+len(label) > 255 || len(context) > 255 { // It should be impossible for this to panic: labels...