Contents
Client-side SSL
For excessively paranoid client authentication.
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.
Original posting: https://gist.github.com/mtigas/952344#client-side-ssl