Tutorial to configure Nginx client-side SSL certificates.

nginx-config-auth-cert-ssl.md

Client-side SSL

For excessively paranoid client authentication.

Original: https://gist.github.com/mtigas/952344

Convert SSL certificate from CRT format to PEM

openssl x509 -in server.crt -out server.der -outform DER
openssl x509 -in server.der -inform DER -out server.pem -outform PEM

Converte PKCS7 to PEM

openssl pkcs7 -in cert.p7b -inform DER -print_certs -out cert.pem

Using self-signed certificate.

Create a Certificate Authority root (which represents this server)

Organization & Common Name: Some human identifier for this server CA.

openssl genrsa -des3 -out ca.key 4096
openssl req -new -x509 -days 365 -key ca.key -out ca.crt

Create the Client Key and CSR

Organization & Common Name = Person name

openssl genrsa -des3 -out client.key 4096
openssl req -new -key client.key -out client.csr
# self-signed
openssl x509 -req -days 365 -in client.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out client.crt

Convert Client Key to PKCS

So that it may be installed in most browsers.

openssl pkcs12 -export -clcerts -in client.crt -inkey client.key -out client.p12

Convert Client Key to (combined) PEM

Combines client.crt and client.key into a single PEM file for programs using openssl.

openssl pkcs12 -in client.p12 -out client.pem -clcerts

Install Client Key on client device (OS or browser)

Use client.p12. Actual instructions vary.

Install CA cert on nginx

So that the Web server knows to ask for (and validate) a user's Client Key against the internal CA certificate.

ssl_client_certificate /path/to/ca.crt;
ssl_verify_client optional; # or `on` if you require client key

Configure nginx to pass the authentication data to the backend application:

• Client Side Certificate Auth in Nginx, section “Passing to PHP.”
• SSL module documentation

Using CACert Keys

• Get client key from CACert

• Install client key in client device.

• Install CACert root certs in server and client device.

• Configure nginx, as above.

  openssl req -new -newkey rsa:2048 -nodes -keyout teste.com.key -out teste.com.csr openssl x509 -req -in teste.com.csr -signkey teste.com.key -out teste.com.crt openssl pkcs12 -export -out teste.com.pfx -inkey teste.com.key -in teste.com.crt

NGINX conf

server {

	listen 80;
	server_name example.com;
	return 301 https://example.com$request_uri;


}


server {

	listen 443 ssl;

	client_max_body_size 60M;
	server_name example.com;

	ssl_certificate /letsencrypt/live/example.com/fullchain.pem;
	ssl_certificate_key /letsencrypt/live/example.com/privkey.pem;


	ssl_protocols TLSv1.1 TLSv1.2;
	ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!3DES:!MD5:!PSK';
	ssl_prefer_server_ciphers on;


	# Cadeia de Certificados
	ssl_client_certificate /etc/nginx/certificados/cadeia-certificados.pem;

	# Valida a hierarquia ( https://stackoverflow.com/questions/8431528/nginx-ssl-certificate-authentication-signed-by-intermediate-ca-chain )
	ssl_verify_depth 2;


	# Certificados revogados
	# ssl_crl /etc/nginx/certificados/ca.crl;
	# Exige o certificad do cliente
	ssl_verify_client on;


	 location / {

	  # Passa o certificado obtido em formato pem para a aplicação

	  proxy_set_header X-Forwarded-Host $server_name;
	  proxy_set_header X-Forwarded-Port 443;
	  proxy_set_header X-Forwarded-Ssl on;
	  # proxy_set_header X-SSL-CERT $ssl_client_cert;
	  proxy_set_header X-SSL-CERT $ssl_client_escaped_cert;
	  proxy_pass http://10.0.0.1:3000;
    }



}