Plasma GitLab Archive
Projects Blog Knowledge

Module Https_client


module Https_client: sig .. end
HTTPS extension to Http_client

type channel_binding_id = int 
class type transport_channel_type = object .. end
val https_transport_channel_type : ?verify:(Ssl.context -> Ssl.socket -> Unix.file_descr -> unit) ->
Ssl.context -> transport_channel_type
Configures a TLS tunnel for this context.

The verify callback is invoked right after connecting to the remote socket and finishing the SSL handshake. The user can do here additional checks whether the peer is acceptable. If not acceptable, raise an exception.


How to configure a pipeline for TLS

Just follow this recipe:

1. Create the Ssl context:

 Ssl.init() 

 let ctx = Ssl.create_context Ssl.TLSv1 Ssl.Client_context 

2. Create the transport channel type:

 let tct = Https_client.https_transport_channel_type ctx 

3. Configure the transport:

 pipeline # configure_transport Http_client.https_cb_id tct 

Now all URLs starting with "https://" will use this transport. If you need more control about the type of SSL/TLS channel, you can create new channel binding IDs, and configure these in addition. For each message needing a specific context, just set the channel binding ID (method set_channel_binding of the message).

How to configure the Convenience module

Just do once:

    Ssl.init();
    Http_client.Convenience.configure_pipeline
      (fun p ->
         let ctx = Ssl.create_context Ssl.TLSv1 Ssl.Client_context in
         let tct = Https_client.https_transport_channel_type ctx in
         p # configure_transport Http_client.https_cb_id tct
      )
    

This will enable "https" for the functions in Http_client.Convenience, e.g.

 let data = Http_client.Convenience.http_get "https://url" 


How to configure Http_fs

Just do once:

    Ssl.init()
    

and create the http_fs object with

    Http_fs.http_fs 
      ~config_pipeline:(
        fun p ->
	  let ctx = Ssl.create_context Ssl.TLSv1 Ssl.Client_context in
	  let tct = Https_client.https_transport_channel_type ctx in
	  p # configure_transport Http_client.https_cb_id tct
      )
      "https://root-url"
    


Features and limitations

We only implement RFC 2618, i.e. secure connections on a separate port (443 instead of 80). There is no support (yet) for RFC 2617, i.e. upgrading an existing insecure connection to a secure one.

If an HTTP proxy server is configured, the TLS connection is established via the CONNECT method (documented in RFC 2617).

Alternatively, it is also possible to connect via SOCKS version 5 proxies.

There is, so far, no support for reusing TLS sessions across connections. For every connection a new TLS session is created.

This web site is published by Informatikbüro Gerd Stolpmann
Powered by Caml