server-configs-nginx/h5bp/ssl/policy_intermediate.conf

# ----------------------------------------------------------------------
# | SSL policy - Intermediate                                          |
# ----------------------------------------------------------------------

# For services that don't need backward compatibility, the parameters
# below provide a higher level of security.
#
# (!) This policy enfore a strong SSL configuration, which may raise
#     errors with old clients.
#     If a more compatible profile is required, use intermediate policy.
#
# (1) The NIST curves (prime256v1, secp384r1, secp521r1) are known
#     to be weak and potentially vulnerable but are required to support
#     Microsoft Edge and Safari.
#     https://safecurves.cr.yp.to/
#
# https://wiki.mozilla.org/Security/Server_Side_TLS#Recommended_configurations
# https://nginx.org/en/docs/http/ngx_http_ssl_module.html

ssl_protocols TLSv1.2;
ssl_ciphers EECDH+CHACHA20:EECDH+AES;

# (1)
ssl_ecdh_curve X25519:prime256v1:secp521r1:secp384r1;