Recommended TLS Ciphers for Traefik

Edit: as noted in the issue linked below, the config-generator has been fixed.

I found this question while researching the cipher suites for Traefik. So, for future reference, and people who have tried the generator but ran into problems:

I found the ssl-config page of Mozilla, that Rui Martins mentioned as well. This works fine, except for the last four entries.

TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256
TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256
TLS_DHE_RSA_WITH_AES_256_GCM_SHA384
TLS_DHE_RSA_WITH_AES_128_GCM_SHA256

Are not recognized by Traefik as valid cipher suites.
I checked the Go documentation, and found that the cipher suites aren't mentioned there either. Relatively close alternatives were mentioned however: https://godoc.org/crypto/tls#pkg-constants

So I replaced the values as follows:

+-----------------------------------------------+----------------------------------------+
| Old Value                                     | New Value                              |
+-----------------------------------------------+----------------------------------------+
| TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256 | ‎TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305 |
+-----------------------------------------------+----------------------------------------+
| TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256   | TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305   |
+-----------------------------------------------+----------------------------------------+
| TLS_DHE_RSA_WITH_AES_256_GCM_SHA384           | TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384  |
+-----------------------------------------------+----------------------------------------+
| TLS_DHE_RSA_WITH_AES_128_GCM_SHA256           | TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256  |
+-----------------------------------------------+----------------------------------------+

Note the removed _SHA256 for the first two entries, and the added EC for the last two.

This works fine, but is not a solution for the core problem. As I do not have a lot of knowledge or experience in cipher suites, I have filed a bug report with Mozilla about their ssl-config generation for Traefik. ( https://github.com/mozilla/ssl-config-generator/issues/52 )

You can use this page to generate your traefik config: https://ssl-config.mozilla.org/#server=traefik&server-version=1.7.12&config=intermediate

# generated 2019-07-17, https://ssl-config.mozilla.org/#server=traefik&server-version=1.7.12&config=intermediate
defaultEntryPoints = ["http", "https"]

[entryPoints]
  [entryPoints.http]
  address = ":80"
    [entryPoints.http.redirect]
    entryPoint = "https"

  [entryPoints.https]
  address = ":443"
    [entryPoints.https.tls]
      minVersion = "VersionTLS12"
      cipherSuites = [
        "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384",
        "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384",
        "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256",
        "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256",
        "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256",
        "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256",
        "TLS_DHE_RSA_WITH_AES_256_GCM_SHA384",
        "TLS_DHE_RSA_WITH_AES_128_GCM_SHA256"
      ]

      [[entryPoints.https.tls.certificates]]
      certFile = "/path/to/signed_cert_plus_intermediates"
      keyFile = "/path/to/private_key"