- 'ec': '-Cnist-p256'}[conf['kx']]),
- ('kx-attrs', 'serialization=constlen'),
+ 'ec': '-Cnist-p256',
+ 'x25519': '',
+ 'x448': ''}[conf['kx']]),
+ ('kx-attrs', lambda: {'dh': 'serialization=constlen',
+ 'ec': 'serialization=constlen',
+ 'x25519': '',
+ 'x448': ''}[conf['kx']]),