Sinatra + HTTPS redirect to HTTP? - ruby

Is it possible to have a Sinatra web server detect an HTTPS:// connection and redirect it to a HTTP:// connection with the same URL, and not have to deal with SSL certificates? I tried stunnel to redirect but it's asking for a cert.

With HTTPS, the first thing a browser does is to create a secure connection to the webserver. For this, it requires a valid server certificate. Before the secure connection is established, you can not perform any HTTP redirect yet.
Thus, to be able to perform any redirects from https to http, you need to have a valid SSL certificate on the server. And in that case, you should really think about having SSL enabled for all content anyway.

Related

Web socket problem - secure connection to 127.0.0.1 - do i need to buy certificate?

What we have:
serverone.exe - util (like a local web proxy) which have support with Websocket.
After user opens a http site (abcd.com) Browser (IE or Firefox) redirects some requests to serverone.exe via websocket.
This connection must be secure in order to browser work well. https -> https
So I have to buy a tls cert for 2 years? Right?
And use domain "test1.com" and then associate it with 127.0.0.1 in hosts.
Is there any other ways to do it nice? without certificates and hosts.
Sorry for my English.

Does squidman proxy server support https?

I'm trying to set up a proxy server on my local mac.
http - seems to work.
But Safari is not connecting via https.
Did I miss something?
No it doesn't. You need to specify a separate https port and a ssl certificate, as documented in the squid config:
The socket address where Squid will listen for client requests made
over TLS or SSL connections. Commonly referred to as HTTPS.
This is most useful for situations where you are running squid in
accelerator mode and you want to do the TLS work at the accelerator
level.
You may specify multiple socket addresses on multiple lines, each
with their own certificate and/or options.
The tls-cert= option is mandatory on HTTPS ports.
See http_port for a list of modes and options.
http://www.squid-cache.org/Doc/config/https_port/
By design, it is quite hard to intercept https traffic:
When a browser creates a direct secure connection with an origin
server, there are no HTTP CONNECT requests. The first HTTP request
sent on such a connection is already encrypted. In most cases, Squid
is out of the loop: Squid knows nothing about that connection and
cannot block or proxy that traffic.
You also need to load the proxy settings for the browser as a PAC file, otherwise the browsers won't connect or throw a certificate warning:
Chrome The Chrome browser is able to connect to proxies over SSL
connections if configured to use one in a PAC file or command line
switch. GUI configuration appears not to be possible (yet).
More details at
http://dev.chromium.org/developers/design-documents/secure-web-proxy
Firefox The Firefox 33.0 browser is able to connect to proxies over
TLS connections if configured to use one in a PAC file. GUI
configuration appears not to be possible (yet), though there is a
config hack for embedding PAC logic.
There is still an important bug open:
Using a client certificate authentication to a proxy:
https://bugzilla.mozilla.org/show_bug.cgi?id=209312
https://wiki.squid-cache.org/Features/HTTPS

How can a web page send a message to the local network

Our web application has a button that is supposed to send data to a server on the local network that in turn prints something on a printer.
So far it was easy: The button triggered an AJAX POST request to http://printerserver/print.php with a token, that page connected to the web application to verify the token and get the data to print and then printed.
However, we are now delivering our web application via HTTPs (and I would rather not go back to HTTP for this) and newer versions of Chrome and Firefox don't make the request to the HTTP address anymore, they don't even send the request to check CORS headers.
Now, what is a modern alternative to the cross-protocol XHR? Do Websockets suffer from the same problem? (A Google search did not make clear what is the current state here.) Can I use TCP Sockets already? I would rather not switch to GET requests either, because the action is not idempotent and it might have practical implications with preloading and caching.
I can change the application on the printerserver in any way (so I could replace it with NodeJS or something) but I cannot change the users' browsers (to trust a self-signed certificate for printerserver for example).
You could store the print requests on the webserver in a queue and make the printserver periodically poll for requests to print.
If that isn't possible I would setup a tunnel or VPN between the webserver and printserver networks. That way you can make the print request from the webserver on the server-side instead of the client. If you use curl, there are flags to ignore invalid SSL certificates etc. (I still suspect it's nicer to introduce a queue anyway, so the print requests aren't blocking).
If the webserver can make an ssh connection to something on the network where the printserver is on, you could do something like: ssh params user#host some curl command here.
Third option I can think of, if printserver can bind to for example a subdomain of the webserver domain, like: print.somedomain.com, you may be able to make it trusted by the somedomain.com certificate, IIRC you have to create a CSR (Certificate Signing Request) from the printserver certificate, and sign it with the somedomain.com certificate. Perhaps it doesn't even need to be a subdomain for this per se, but maybe that's a requirement for the browser to do it client-side.
The easiest way is to add a route to the webapp that does nothing more than relay the request to the print server. So make your AJAX POST request to https://myapp.com/print, and the server-side code powering that makes a request to http://printerserver/print.php, with the exact same POST content it received itself. As #dnozay said, this is commonly called a reverse proxy. Yes, to do that you'll have to reconfigure your printserver to accept (authenticated) requests from the webserver.
Alternatively, you could switch the printserver to https and directly call it from the client.
Note that an insecure (http) web-socket connection on a secure (https) page probably won't work either. And for good reason: generally it's a bad idea to mislead people by making insecure connections from what appears to them to be a secure page.
The server hosting the https webapp can reverse proxy the print server,
but since the printer is local to the user, this may not work.
The print server should have the correct CORS headers
Access-Control-Allow-Origin: *
or:
Access-Control-Allow-Origin: https://www.example.com
However there are pitfalls with using the wildcard.
From what I understand from the question, printserver is not accessible from the web application so the reverse proxy solution won't work here.
You are restricted from making requests from the browser to the printserver by cross-origin-policy.
If wish to communicate with the printserver from an HTTPS page you will need the printserver to expose print.php as HTTPS too.
You could create a DNS A record as a subdomain of your web application that resolves to the internal address of your printserver.
With those steps in place you should be able to update your printserver page to respond with permissive CORS headers which the browser should then respect. I don't think the browser will even issue CORS requests across different protocol schemes (HTTPS vs HTTP) or to internal domains, without a TLD.

Identify the destination in HTTPS connections

How does the browser figure out the destination in an HTTPS connection? All the headers are encrypted..
Update:No this is not a homework.. my name is student because I'll always be learning in this HUGE awesome field
When a browser views an url like https://www.gmail.com/ first thing your browser does is resolves www.gmail.com to 72.14.213.19.
Next your browser opens up a TCP connection to 72.14.213.19 on port 443.
The browser & server before ANY headers are transmitted negotiate a public key encryption scheme (RSA) based on the SSL Certificate that is digitally signed.
In this process the browser checks the certificate authenticity before communicating.
Once this trust between client & server has been established, the client now can encrypt the headers in a way the server can decrypt. It proceeds to make the HTTP request inside the SSL Tunnel.
The server decrypts the message, serves the request and encrypts it in a way that that particular client can decrypt.
The browser then decrypts the response, reads the headers and makes decisions about how to proceed from there.
This has been an overview of an HTTPS connection event. :D
The string containing https: that you typed in the browser is what the browser uses. That is not encrypted,
Probably more than you'd ever want or need to know about the The First Few Milliseconds of an HTTPS Connection I'd go into more detail explaining stuff if your username wasn't student, and this wasn't likely homework.

Encryption of HTTPS headers

To what extent, if at all, are HTTPS headers encrypted?
They are encrypted in transit through SSL. There is no special encryption dedicated to headers, HTTPS encrypts the entire message.
All headers are encrypted in HTTPS. You may want to look at some documentation on how SSL and TLS work.
SSL sets up a private authenticated link to the server and then sends an http request over that link. The evil-doer snooping on the link cant actually tell from just watching the connection that http is being used. SSL its self has some unencrypted headers that it uses to establish this connection though these should not be confused with the headers that are part of the http protocol.

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