- Default SSL Certificate
- SSL Passthrough
- HTTPS enforcement
- HSTS
- Server-side HTTPS enforcement through redirect
- Kube-Lego
NGINX provides the option to configure a server as a cath-all with server name _ for requests that do not match any of the configured server names. This configuration works without issues for HTTP traffic.
In case of HTTPS, NGINX requires a certificate.
For this reason the Ingress controller provides the flag --default-ssl-certificate
. The secret behind this flag contains the default certificate to be used in the mentioned scenario. If this flag is not provided NGINX will use a self signed certificate.
Running without the flag --default-ssl-certificate
:
$ curl -v https://10.2.78.7:443 -k
* Rebuilt URL to: https://10.2.78.7:443/
* Trying 10.2.78.4...
* Connected to 10.2.78.7 (10.2.78.7) port 443 (#0)
* ALPN, offering http/1.1
* Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
* successfully set certificate verify locations:
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Client hello (1):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS change cipher, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
* ALPN, server accepted to use http/1.1
* Server certificate:
* subject: CN=foo.bar.com
* start date: Apr 13 00:50:56 2016 GMT
* expire date: Apr 13 00:50:56 2017 GMT
* issuer: CN=foo.bar.com
* SSL certificate verify result: self signed certificate (18), continuing anyway.
> GET / HTTP/1.1
> Host: 10.2.78.7
> User-Agent: curl/7.47.1
> Accept: */*
>
< HTTP/1.1 404 Not Found
< Server: nginx/1.11.1
< Date: Thu, 21 Jul 2016 15:38:46 GMT
< Content-Type: text/html
< Transfer-Encoding: chunked
< Connection: keep-alive
< Strict-Transport-Security: max-age=15724800; includeSubDomains; preload
<
<span>The page you're looking for could not be found.</span>
* Connection #0 to host 10.2.78.7 left intact
Specifying --default-ssl-certificate=default/foo-tls
:
core@localhost ~ $ curl -v https://10.2.78.7:443 -k
* Rebuilt URL to: https://10.2.78.7:443/
* Trying 10.2.78.7...
* Connected to 10.2.78.7 (10.2.78.7) port 443 (#0)
* ALPN, offering http/1.1
* Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
* successfully set certificate verify locations:
* CAfile: /etc/ssl/certs/ca-certificates.crt
CApath: /etc/ssl/certs
* TLSv1.2 (OUT), TLS header, Certificate Status (22):
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Server hello (2):
* TLSv1.2 (IN), TLS handshake, Certificate (11):
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
* TLSv1.2 (IN), TLS handshake, Server finished (14):
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
* TLSv1.2 (OUT), TLS change cipher, Client hello (1):
* TLSv1.2 (OUT), TLS handshake, Finished (20):
* TLSv1.2 (IN), TLS change cipher, Client hello (1):
* TLSv1.2 (IN), TLS handshake, Finished (20):
* SSL connection using TLSv1.2 / ECDHE-RSA-AES128-GCM-SHA256
* ALPN, server accepted to use http/1.1
* Server certificate:
* subject: CN=foo.bar.com
* start date: Apr 13 00:50:56 2016 GMT
* expire date: Apr 13 00:50:56 2017 GMT
* issuer: CN=foo.bar.com
* SSL certificate verify result: self signed certificate (18), continuing anyway.
> GET / HTTP/1.1
> Host: 10.2.78.7
> User-Agent: curl/7.47.1
> Accept: */*
>
< HTTP/1.1 404 Not Found
< Server: nginx/1.11.1
< Date: Mon, 18 Jul 2016 21:02:59 GMT
< Content-Type: text/html
< Transfer-Encoding: chunked
< Connection: keep-alive
< Strict-Transport-Security: max-age=15724800; includeSubDomains; preload
<
<span>The page you're looking for could not be found.</span>
* Connection #0 to host 10.2.78.7 left intact
The flag --enable-ssl-passthrough
enables SSL passthrough feature.
By default this feature is disabled
By default the controller redirects (301) to HTTPS if TLS is enabled for that ingress . If you want to disable that behaviour globally, you can use ssl-redirect: "false"
in the configuration ConfigMap.
To configure this feature for specific ingress resources, you can use the ingress.kubernetes.io/ssl-redirect: "false"
annotation in the particular resource.
HTTP Strict Transport Security (HSTS) is an opt-in security enhancement specified through the use of a special response header. Once a supported browser receives this header that browser will prevent any communications from being sent over HTTP to the specified domain and will instead send all communications over HTTPS.
By default the controller redirects (301) to HTTPS if there is a TLS Ingress rule.
To disable this behavior use hsts: "false"
in the configuration ConfigMap.
By default the controller redirects (301) to HTTPS
if TLS is enabled for that ingress. If you want to disable that behavior globally, you can use ssl-redirect: "false"
in the NGINX config map.
To configure this feature for specific ingress resources, you can use the ingress.kubernetes.io/ssl-redirect: "false"
annotation in the particular resource.
When using SSL offloading outside of cluster (e.g. AWS ELB) it may be useful to enforce a redirect to HTTPS
even when there is not TLS cert available. This can be achieved by using the ingress.kubernetes.io/force-ssl-redirect: "true"
annotation in the particular resource.
Kube-Lego automatically requests missing or expired certificates from Let's Encrypt by monitoring ingress resources and their referenced secrets. To enable this for an ingress resource you have to add an annotation:
kubectl annotate ing ingress-demo kubernetes.io/tls-acme="true"
To setup Kube-Lego you can take a look at this full example. The first version to fully support Kube-Lego is nginx Ingress controller 0.8.