What is a bootstrap-proxy in Chef? - proxy

I am looking at this http://tickets.opscode.com/browse/CHEF-2375 and I am a bit confused as to what this option is useful for. I understand the idea of a proxy node in general as described here: http://en.wikipedia.org/wiki/Proxy_server
Can someone explain the use of a bootstrap-proxy in Chef?

Basically the bootstrap-proxy allows you to specify a HTTP proxy server when setting up your servers.
This is probably not a big deal for most people, but there are a few cases where you need/want an HTTP proxy.
Some networks are set up to require the use of an HTTP proxy in order to make outbound HTTP connections. This can provide some added security as well as a wealth of control on the part of the network admin. Without http proxy support the knife bootstrap command would be unable to make any HTTP connections.
Added an HTTP proxy as a cache can make commands like apt-get run much faster, especially on a slow connection. Essentially your proxy can cache any packages you download while the first server won't see much of a difference, any subsequent servers will download packages directly from the cache which can be much faster.

Related

Caching proxy for all traffic

I am trying to find (or write) a caching proxy tool that accepts all traffic from a specific container in my localhost (using Iptables). What I want to do with this traffic is to save it and cache the response, and later, if I see that a request was already sent to a server, return the cached response to the requesting party (and not sending the request to the server again, because a previous similar request was already sent).
Here's a diagram to demonstrate what I'm trying to do:
I'm not sure exactly how big is the problem I'm trying to deal with here. I want to do it for all traffic, including HTTP, TLS and other TCP based traffic (database connections and such). I tried to check mitmproxy, and it seems to deal pretty good with HTTP and the TLS part, but intercepting raw TCP traffic (for databases etc.) is not possible.
Any advices or resources I can use to accomplish that? (Not necessarily in Python). How complex do you think this problem is? Do you think I can find a generic solution?
Thanks in advance!

Outbound https proxy sidecar

Let's say I have a Kubernetes Job that makes https requests to changing URLs and I want to allow specific URLs only and block all other requests. My idea is deploy an Https-Proxy-Pod and use NetworkPolicies to make sure the Job-Pod can only communicate with the Https-Proxy-Pod. See following sketch for better understanding:
sketch of https-proxy sidecar deployment
I know how to do that but have no idea what Https Proxy to use. As far as I understood envoy is not a suitable solution for what I want to do: https://github.com/envoyproxy/envoy/issues/1606
Does anyone has a better solution or can tell me which proxy to use?
Mitmproxy is an open source tool that you can use to filter HTTP and HTTPS requests transparently using the Python scripting language.
There's also a quite detailed tutorial on how to use it

what is the difference between a proxy server like tor and a proxy tool like paros?

it seems to be a big difference between them but eventually, both of them use a proxy
but paros can modify an intercept HTTP and HTTPS request , and tor just "make me invisible" ?
how does it work ?
Paros and Tor serve different purposes. The first is a vulnerability scanner which might take your input, modify it and send it to the target website. Tor on the other side doesn't modify your requests, but wraps around encryption layers and send the requests over some servers until it reaches the target.
If you have Paros installed locally and send your requests through the software, the target website will see your IP address. Tor's purpose is to hide your IP address. So the target website will see some other address than your.
For specific questions on Paros you might want to have a look at security.SE site. Questions about Tor are handled at tor.SE.

AWS ELB Server-Side HTTPS

I have been working my way though setting up HTTPS using AWS. I have been attempting this with a self-signed certificate and am finding the process a bit problematic.
One question that has come up along the way is this business of server-side HTTPS. The client that I am working with requests that when a user hits the server the URL change to HTTPS. I am wondering if "Server-Side HTTPS" means that the protocol is transparent to the end-user?
Will they still see HTTP int the browser?
Thanks.
Don't know if this is an exact answer to your question, but rather perhaps a piece of advice. When using ELB, I have found it MUCH easier to install the SSL cert on the ELB and use SSL offload to forward requests from port 443 on ELB to port 80 on the EC2 instances.
The pros of this:
There is only one place where you need to install the cert rather than having to install across a number of instances (or update AMI and relaunch instances), making cert updates much easier to perform.
You get better performance on your web servers as they don't have to deal with SSL encryption.
Some cons:
The communication is not encrypted end-to-end so there is the technical (albeit unlikely) chance that the communication could be intercepted between ELB and servers. If you are dealing with something like PCI compliance this might matter to you.
If you needed to directly access one of the instances over HTTPS that would not be possible.
You may need to make sure your application is aware of the https-related headers (i.e. x-forwarded-proto) that the ELB injects into the request if your application needs to check whether the request is over HTTPS.
There is no reason that this configuration would disallow you from redirecting incoming requests over HTTP to HTTPS. You might however need to look the x-forwarded-proto header to do any web-server or application level redirects to HTTPS. The end user would not have any way of knowing that their HTTPS wrapper for their request was being offloaded at the ELB.

How to build local web proxy without configuring the browsers

How does Netnanny or k9 Web Protection setup web proxy without configuring the browsers?
How can it be done?
Using WinSock directly, or at the NDIS or hardware driver level, and
then filter at those levels, just like any firewalls soft does. NDIS being the easy way.
Download this ISO image: http://www.microsoft.com/downloads/en/confirmation.aspx?displaylang=en&FamilyID=36a2630f-5d56-43b5-b996-7633f2ec14ff
it has bunch of samples and tools to help you build what you want.
After you mount or burn it on CD and install it go to this folder:
c:\WinDDK\7600.16385.1\src\network\ndis\
I think what you need is a transparent proxy that support WCCP.
Take a look at squid-cache FAQ page
And the Wikipedia entry for WCCP
With that setup you just need to do some firewall configuration and all your web traffic will be handled by the transparent proxy. And no setup will be needed on your browser.
netnanny is not a proxy. It is tied to the host machine and browser (and possibly other applications as well. It then filters all incoming and outgoing "content" from the machine/application.
Essentially Netnanny is a content-control system as against destination-control system (proxy).
Easiest way to divert all traffic to a certain site to some other address is by changing hosts file on local host
You might want to have a look at the explanation here: http://www.fiddlertool.com/fiddler/help/hookup.asp
This is how Fiddler2 achieves inserting a proxy in between most apps and the internet without modifying the apps (although lots of explanation of how-to failing the default setup). This does not answer how NetNanny/K9 etc work though, as noted above they do a little more and may be a little more intrusive.
I believe you search for BrowserHelperObjects. These little gizmos capture ALL browser communication, and as such can either remote ads from the HTML (good gizmo), or redirect every second click to a spam site (bad gizmo), or just capture every URL you type and send it home like all the WebToolBars do.
What you want to do is route all outgoing http(s) requests from your lan through a reverse proxy (like squid). This is the setup for a transparent web proxy.
There are different ways to do this, although I've only ever set it up OpenBSD and Linux; and using Squid as the reverse proxy.
At a high level you have a firewall with rules to send all externally bound http traffic to a local squid server. The Squid server is configured to:
accept all http requests
forward the requests on to the real external hosts
cache the reply
forward the reply back to the requestor on the local lan
You can then add more granular rules in Squid to control access to websites, filter content, etc.
I pretty sure you can also get this functionality in different networking gear. I bet F5 has some products that do some or all of what I described, and probably Cisco as well. There is probably other proxies out there besides Squid that you can use too.
PS. I have no idea if this is how K9 Web Protection or NetNanny works.
Squid could provide an intercept proxy for HTTP and HTTPs ports, without configuring the browsers and it also supports WCCP.

Resources