PROD-1704: Pass TLS client cert variables to EPRI rails app as header

Allows EPRI to perform CN validation

nginx.conf

@@ -1,28 +1,28 @@
-server {
-    listen       80;
-    server_name  localhost;
-
-    # Don't advertise
-    server_tokens off;
-
-    # Don't merge slashes
-    merge_slashes off;
-
-    root /dev/null;
-
-      location / {
-        proxy_set_header  X-Real-IP        $remote_addr;
-        proxy_set_header  X-Forwarded-For  $proxy_add_x_forwarded_for;
-        proxy_set_header  Host             $http_host;
-        proxy_redirect    off;
-        proxy_pass http://vtn-rails:8080;
-      }
+map $ssl_client_s_dn $ssl_client_s_dn_cn {
+	default "no_client_cert";
+	~(^|,)CN=(?<CN>[^,]+) $CN;
 }
 
 server {
-    listen 443 ssl default_server;
+    listen 443 ssl;
     server_name localhost;
     root /dev/null;
+    
+    # TODO: once the JACE sends an official Kyrio cert, this can be set to 
+    # 'on' so the trust-chain is verified against the CA certs in ssl.crt.
+    # Also may require tuning of ssl_verify_depth directive.
+
+    # In its current state EPRI will validate that the client cert's CN
+    # is correct, but in theory someone could spoof it with a self-signed
+    # certificate containing the "correct" CN.
+
+    # Also note that webui admin routes will likely be hit without a client
+    # cert, so you will probably want to either:
+    # a) have a seperate server/vhost for VEN traffic vs. admin traffic
+    # b) leave ssl_verify_client at optional or optional_no_ca, and match
+    #    on $ssl_client_verify in a location block.
+
+    ssl_verify_client optional_no_ca;
 
     # Don't advertise
     server_tokens off;
@@ -38,6 +38,12 @@ server {
         proxy_set_header  X-Forwarded-Ssl on;
         proxy_set_header  X-Forwarded-Port $server_port;
         proxy_set_header  X-Forwarded-Host $host;
+
+        # these next two headers are consumed by EPRI to validate client cert
+        # CN vs. EPRI VEN Common Name.
+        proxy_set_header  SSL_CLIENT_S_DN_CN $ssl_client_s_dn_cn; 
+        proxy_set_header  HTTPS true;
+        
         proxy_redirect    off;
         proxy_pass http://vtn-rails:8080;
     }