How to configure saml 2.0 in nginx server?

How can I configure saml 2.0 in nginx, if I have only .cert file and .xml file?

Below are my nginx server configuration

1. /etc/nginx/nginx.conf

user  nginx;
worker_processes  auto;

error_log  /var/log/nginx/error.log warn;
pid        /var/run/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       /etc/nginx/mime.types;
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    keepalive_timeout  65;

    #gzip  on;

    include /etc/nginx/conf.d/*.conf;
}

2. /etc/nginx/conf.d/default.conf file

server {
    server_name < hostname >;

    #charset koi8-r;
    #access_log  /var/log/nginx/host.access.log  main;

    location / {
    root   /var/www/html;
        index  index.html index.htm;
    try_files $uri $uri/ /index.html;
    }

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }

}

I’ve no clue how to configure saml on that. Any ideas?