nginx doesn't support ECDHE-ECDSA-AES128-GCM-SHA256 cipher suite

Question

I have a device that is trying to connect with the following Client Hello captured from Wireshark:

It looks like the only Cipher Suite it supports is ECDHE-ECDSA-AES128-GCM-SHA256, I'm therefor trying to enable this with nginx.

events {

}

http {
    server {
        listen 443 ssl;
        ssl_certificate /etc/nginx/certs/nginx.crt;
        ssl_certificate_key /etc/nginx/certs/nginx.key;
        server_name xxx.yyy.zzz;
        ssl_ciphers 'ECDHE-ECDSA-AES128-GCM-SHA256';
    }
}

I don't get an error when running nginx with that config:

$ docker run -p 443:443 -v (pwd):/etc/nginx/certs -v (pwd)/nginx.conf:/etc/nginx/nginx.conf nginx

However, the list of supported ciphers comes back null with sslscan:

$ sslscan localhost
Version: 1.11.12-static
OpenSSL 1.0.2f  28 Jan 2016

ERROR: Could not open a connection to host localhost (::1) on port 443.
Connected to 127.0.0.1

Testing SSL server localhost on port 443 using SNI name localhost

  TLS Fallback SCSV:
Server supports TLS Fallback SCSV

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:
TLS 1.2 not vulnerable to heartbleed
TLS 1.1 not vulnerable to heartbleed
TLS 1.0 not vulnerable to heartbleed

  Supported Server Cipher(s):
$

I'm not an ops guy, so I'm not familiar with setting up servers. I just need to get this IoT device to connect to my server.

So how can I go about enabling the ECDHE-ECDSA-AES128-GCM-SHA256 cipher suite with nginx?

Answer 1

You can view available ssl_ciphers using:

openssl ciphers

To get a more "eye friendly" output try:

openssl ciphers | egrep --color 'ECDHE-ECDSA-AES128-GCM-SHA256'

to check if your desired cipher is available to nginx.