I have to use a portal that uses AJAX requests not only to the base SSL port (443) of the server, there are also a SSL request to the 8443 port.
My squid denies these request due to the rule:
http_access deny CONNECT !SSL_ports
Adding the 8443 port to the SSL_ports solves the problem, but I am not sure this is a security constraint. Is it?
I am in contact with the operator of the site. Should I try to force them to think about another solution? What are the reasons to change their site behavior?
Regards
Rainer
What are the reasons to change their site behavior?
The main reason is that they likely want their site to be reachable.
It is not uncommon today that firewalls (and not only proxies) restrict access to only port 80 and 443 which means that valued customers could have problems to properly interact with their site. This can mean loss of business or additional costs related to supporting unhappy customers.
Related
I have already installed an Apache HTTP server in my RedHat system, now I need to install a Bitnami application package which contains another Apache. So I am wondering how to make them not disturbing each other?
I guess I need to configure different ports for the two HTTP server. But what if one has 8080 and another has 9090, will we visit http://[ServerName]:8080/something.html and http://[ServerName]:9090/something.html? I think this way is quite inconvenient. Am I wrong or any better idea?
My advice would be to do something like this.
Have one Apache instance listen in port 80 and the other one in port 8080 for example. The Apache instance that listens in port 80 can act as a proxy to the other Apache (port 8080) using the ProxyPass and ProxyPassReverse directives.
https://httpd.apache.org/docs/2.4/mod/mod_proxy.html
You would need to define prefixes or virtual hosts and inside them add ProxyPass directives.
I don't know to what kind of user those applications are targeted to but the usual end-user is not used to enter ports when browsing the web.
If you like to use the ports, go for it, but I would recommend using Name-based Virtual Host
so you could use different domains or subdomains to each application.
In addition to the example provided by the docs (in where they just point to different folders) in this digitalocean page they document how to make redirects to different urls.
I completely agree with EndermanAPM that usual end-user is not used to enter ports when browsing the web. Therefore, I would only allow port 80 to be accessed by the end-users.
Additional to the current solutions I see another one:
avoid messing up the settings of the Apache servers in order to not end-up with some malfunctions of your websites
leave the Apache servers listen on their designated ports (8080 respectively 9090)
install a dedicated proxy in front of the Apache servers. The proxy would listen on port 80 and would define redirect rules that would parse the request and would redirect it to the proper Apache server. (see the attached picture)
I recommend you HA Proxy. It is a very fast and reliable http and tcp proxy. I've been using it in production for years, in front of application servers, web servers and even database servers. Once you get used with its syntax, it is pretty easy to use.
I am aware that introducing a new component into the equation might add another source of potential issues. But I think that the architecture is cleaner. Besides, the two Apache servers will not be disturbing each other as you requested. You can shut down any one of the two and the other one would properly work further.
example1.com and example2.com resolve to host0. host0 runs an Apache reverse proxy with two VirtualHosts. It delegates requests for example1.com to host1 and for example2.com to host2.
Using http in all places, that clearly can be made to work.
Using https, I could stick the keys for example1.com and example2.com on host0, and then have host0 talk http or https to host1 and host2. Given SNI, that should work, too.
My question: can it be made to work without the example1.com or example2.com keys on host0? I'd like to avoid that host0 is in a position to perform a man-in-the-middle attack.
If I understand SNI correctly, the key material is only exchanged after the client has communicated the desired virtual host to host0. This should be (?) sufficient information for Apache to essentially forward the connection to host1 or host2, without looking at the content of the transmission at all. That does not require key material at all.
Do you really need Apache reverse proxy, or you need the problem solved? I had the same problem and I resolved it with HAProxy in tcp mode as described here http://blog.haproxy.com/2012/04/13/enhanced-ssl-load-balancing-with-server-name-indication-sni-tls-extension/ instead of Apache reverse proxy.
If you don't mind using Nginx or HAProxy instead of Apache, you'll find good answers at the following question at ServerFault:
Can a Reverse Proxy use SNI with SSL pass through?
For reasons we're not going to change, our application needs to handle the SSL connection, and not the ELB. The goal of using the Proxy Protocol is to get the client's IP address over an SSL connection.
http://aws.typepad.com/aws/2013/07/elastic-load-balancing-adds-support-for-proxy-protocol.html?ref_=9 indicates "Alternatively, you can use it if you are sending HTTPS requests and do not want to terminate the SSL connection on the load balancer. For more information, please visit the Elastic Load Balancing Guide."
Unfortunately, it appears the guide that's linked to doesn't actually elaborate on this, and the basic documentation for the Proxy Protocol ( http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/enable-proxy-protocol.html ) fails in our environment when configured as described.
Does anyone have steps or a link for this?
The proxy protocol (version 1) injects a single line into the data stream at the beginning of the connection, before SSL is negotiated by your server. You don't get this information "over" an SSL connection; you get the information prior to SSL handshaking. Your server has to implement this capability and specifically be configured so that it can accept and understand it. For an IPv4 connection, it looks like this:
PROXY TCP4 source-ip dest-ip source-port dest-port\r\n
The standard for the protocol is here:
http://haproxy.1wt.eu/download/1.5/doc/proxy-protocol.txt
Additional info in the ELB docs here:
http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/TerminologyandKeyConcepts.html#proxy-protocol
Regarding Apache support, at least at the time AWS announced support for the proxy protocol...
“neither Apache nor Nginx currently support the Proxy Protocol header inserted by the ELB”
— http://aws.typepad.com/aws/2013/07/elastic-load-balancing-adds-support-for-proxy-protocol.html?ref_=9
That is subject to change, of course, but I didn't successfully google for any Apache support of the proxy protocol. Of course, since Apache is open source, you could presumably hack it in there, though I am unfamiliar with the Apache source code.
Realizing that you don't want to change what you're doing now, I still would suggest that depending on your motivation for not wanting to change, there may still be a relatively simple solution. It's a change, but not involving SSL on ELB. What about running HAProxy behind ELB to terminate the SSL in front of Apache? Since HAProxy 1.5 can terminate SSL and appears to be able to translate the proxy protocol string from ELB into an X-Forwarded-For header, as well as generate X-SSL headers to give your application information about the client's SSL cert (perhaps that's your motivation for terminating SSL at the app server instead of on the ELB?) ... so this might be an alternative.
Otherwise, I don't have suggestions unless Apache implements support in the future, or we can find some documentation to indicate that they already have.
For the newer Network Load Balancers which allow your application servers to terminate the TLS connections, you can still get the real IP addresses of your clients and avoid all the work of configuring proxy protocol on the ELBs and in the web server config by simply configuring the target groups to use the servers' instance ids rather than their IP addresses. Regardless of which web server you use, the real IPs of the clients will show up in the logs with no translation needed.
Just to follow up on Michael - sqlbot's answer discussing the AWS support for proxy protocol on EC2 instances behind classic TCP elastic load balancers, the Apache module to use that implements the proxy protocol is mod_remoteip. Enabling it and updating the configuration properly will correct the problem of logging IP addresses of users rather than the elastic load balancer's IPs.
To enable proxy protocol on the elastic load balancer you could use these aws cli commands described in the aws documentation:
aws elb create-load-balancer-policy --load-balancer-name my-elb-name --policy-name my-elb-name-ProxyProtocol-policy --policy-type-name ProxyProtocolPolicyType --policy-attributes AttributeName=ProxyProtocol,AttributeValue=true
aws elb set-load-balancer-policies-for-backend-server --load-balancer-name my-elb-name --instance-port 443 --policy-names my-elb-name-ProxyProtocol-policy
aws elb set-load-balancer-policies-for-backend-server --load-balancer-name my-elb-name --instance-port 80 --policy-names my-elb-name-ProxyProtocol-policy
To enable use of proxy protocol in apache, in a server-wide or VirtualHost context, follow the mod_remoteip documentation such as below:
<IfModule mod_remoteip.c>
RemoteIPProxyProtocol On
RemoteIPHeader X-Forwarded-For
# The IPs or IP range of your ELB:
RemoteIPInternalProxy 192.168.1.0/24
# The IPs of hosts that may need to connect directly to the web server, bypassing the ELB (if applicable):
RemoteIPProxyProtocolExceptions 127.0.0.1
</IfModule>
You'll need to update the LogFormat wherever you have those defined (e.g. httpd.conf) to use %a rather than %h else the load balancer IP addresses will still appear.
When having multiple domain names point to the same server. But you only have a certificate for one of these domains, is it possible to block the other domains in Apache. But only when HTTPS is used not when HTTP is used.
I tried using a NameVirtualHost setup for 443 port. But when the domain is not found Apache simply defaults to the first virtual host. I would like it to refuse the connection. In this way when connecting directly through HTTPS on one of the not supported domains the connection is refused rather then having the browser display warning screen because of a wrong identity.
Any thoughts?
Not possible.
This is a chicken and egg problem - to verify an https connection the browser connects and tries to validate the certificate/common name and the given URL. The first handshake / connection to port 443 has to be encrypted.
The only way to handle this problem would be to setup dedicated IPs for all domains - or for at least the domain using HTTPS.
It's far from ideal, but another option would be to use a non-standard for your HTTPS site and not have the server listening on port 443.
What are some good ways to do this? Is it even possible to do cleanly?
Ideally I'd like to use packet headers to decide which server should handle requests. However, if there is an easier/better way let me know.
It's impossible for both servers to listen on the same port at the same IP address: since a single socket can only be opened by a single process, only the first server configured for a certain IP/port combination will successfully bind, and the second one will fail.
You will thus need a workaround to achieve what you want. Easiest is probably to run Apache on your primary IP/port combination, and have it route requests for IIS (which should be configured for a different IP and/or port) to it using mod_rewrite.
Keep in mind that the alternative IP and port IIS runs on should be reachable to the clients connecting to your server: if you only have a single IP address available, you should take care to pick an IIS port that isn't generally blocked by firewalls (8080 might be a good option, or 443, even though you're running regular HTTP and not SSL)
P.S. Also, please note that you do need to modify the IIS default configuration using httpcfg before it will allow other servers to run on port 80 on any IP address on the same server: see Micky McQuade's answer for the procedure to do that...
I found this post which suggested to have two separate IP addresses so that both could listen on port 80.
There was a caveat that you had to make a change in IIS because of socket pooling. Here are the instructions based on the link above:
Extract the httpcfg.exe utility from the support tools area on the Win2003 CD.
Stop all IIS services: net stop http /y
Have IIS listen only on the IP address I'd designated for IIS: httpcfg set iplisten -i 192.168.1.253
Make sure: httpcfg query iplisten (The IPs listed are the only IP addresses that IIS will be listening on and no other.)
Restart IIS Services: net start w3svc
Start the Apache service
For people with only one IP address and multiple sites on one server, you can configure IIS to listen on a port other than 80, e.g 8080 by setting the TCP port in the properties of each of its sites (including the default one).
In Apache, enable mod_proxy and mod_proxy_http, then add a catch-all VirtualHost (after all others) so that requests Apache isn't explicitly handling get "forwarded" on to IIS.
<VirtualHost *:80>
ServerName foo.bar
ServerAlias *
ProxyPreserveHost On
ProxyPass / http://127.0.0.1:8080/
</VirtualHost>
Now you can have Apache serve some sites and IIS serve others, with no visible difference to the user.
Edit: your IIS sites must not include their port number in any URLs within their responses, including headers.
You need at least mod_proxy and mod_proxy_http which both are part of the distribution (yet not everytime built automatically). Then you can look here: http://httpd.apache.org/docs/2.2/mod/mod_proxy.html
Simplest config in a virtualhost context is:
ProxyPass /winapp http://127.0.0.1:8080/somedir/
ProxyPassReverse /winapp http://127.0.0.1:8080/somedir/
(Depending on your webapp, the actual config might become more sophisticated. )
That transparently redirects every request on the path winapp/ to the windows server and transfers the resulting output back to the client.
Attention: Take care of the links in the delivered pages: they aren't rewritten, so you can save yourself lotsa hassle if you generally use relative links in your app, like
<a href=../pics/mypic.jpg">
instead of the usual integration nightmare of every link being absolute:
<a href="http://myinternalhostname/somedir/crappydesign.jpg">
THE LATTER IS BAD ALMOST EVERY SINGLE TIME!
For rewriting links in pages there's mod_proxy_html (not to confuse with mod_proxy_http!) but that's another story and a cruel one as well.
Either two different IP addresses (like recommended) or one web server is reverse-proxying the other (which is listening on a port <>80).
For instance: Apache listens on port 80, IIS on port 8080. Every http request goes to Apache first (of course). You can then decide to forward every request to a particular (named virtual) domain or every request that contains a particular directory (e.g. http://www.example.com/winapp/) to the IIS.
Advantage of this concept is that you have only one server listening to the public instead of two, you are more flexible as with two distinct servers.
Drawbacks: some webapps are crappily designed and a real pain in the ass to integrate into a reverse-proxy infrastructure. A working IIS webapp is dependent on a working Apache, so we have some inter-dependencies.
I see this is quite an old post, but came across this looking for an answer for this problem. After reading some of the answers they seem very long winded, so after about 5 mins I managed to solve the problem very simply as follows:
httpd.conf for Apache leave the listen port as 80 and 'Server Name' as FQDN/IP :80.
Now for IIS go to Administrative Services > IIS Manager > 'Sites' in the Left hand nav drop down > in the right window select the top line (default web site) then bindings on the right.
Now select http > edit and change to 81 and enter your local IP for the server/pc and in domain enter either your FQDN (www.domain.com) or external IP close.
Restart both servers ensure your ports are open on both router and firewall, done.
This sounds long winded but literally took 5 mins of playing about. works perfectly.
System:
Windows 8, IIS 8, Apache 2.2
Installing Windows 10 I had this problem: apache(ipv4) and spooler service(ipv6) listening the same 80 port.
I resolved editing apache httpd.conf file changing the line
Listen 80
to
Listen 127.0.0.1:80
That's not quite true. E.g. for HTTP Windows supports URL based port sharing, allowing multiple processes to use the same IP address and Port.
You will need to use different IP addresses. The server, whether Apache or IIS, grabs the traffic based on the IP and Port, which ever they are bound to listen to. Once it starts listening, then it uses the headers, such as the server name to filter and determine what site is being accessed. You can't do it will simply changing the server name in the request