Ubuntu Security :: Only Allowed To Use One Port For Proxy?
Jun 5, 2010
I'm using a local proxy server VPN'd to another network.
How do I setup either Firestarter or Gufw/ufw to ONLY allow in/out from ONE port? (The one port the proxy uses)
Ex: Firefox is proxied to 127.0.0.1, all ports, and then the proxy picks it up, and sends out on port xxxx, and recieves on port xxxx, then sends back thru 127.0.0.1, back to Firefox.
Any setting/rules I've treid on either Firestarter or Gufw kills the proxy>VPN (Proxy won't connect to remote network)
Addendum: If I start the proxy FIRST, then the firewall, all is good. I'm thinking the proxy uses a port to connect with remote network first, then switches to my configured xxxx port...hmmm
While reading some papers on securing apache with selinux, I have tried to bind httpd to port 3000 expecting to be blocked by the selinux, since port tcp 3000 isn't on the http_port_t list. However I was able to start the service...
I'm preety sure selinux is enforcing. Also, if I bind httpd to tcp 81 selinux denies the start of the service, as expected!Did I miss something? Why is httpd allowed to start binded to a port that's not explicitly allowed?
I had just got Arch up and running a couple weeks back, and I was following a random user's guide (previous Ubuntu user and newb to Linux in general)-- I think it may have been a mistake. When I was configuring my iptables/ufw, I'd added a rule to iptables allowing ssh to be used from anywhere (I think so anyhow); it came up as something along the lines of 'ALLOW: IN : ANYWHERE: ssh 22' in red font on gufw.
This had been open for about a few days, and I didn't realize the security risk until I learned what ssh is. So is it likely that my system is compromised and needs a full hard drive wipe? hosts.deny remained in its default state, so wouldn't that override the iptables configuration or no? Could my router have kept any potential threats out like it has before despite the rule?
I installed and configured a squid transparent proxy on my linux os at work. Also it is veryslow but every thing is ok while I do not try to use port 443,so when I try to use sites like mail.yahoo.com or other which are using https(443) port and the method used is CONNECT I see some errors in access.log like:
server: LAMP - debian, apache2, mysql, php5. a bit info on my network: There is a another service here that already uses port 443 already. It made my website time out, hence the move to another port. PLus, i dont want the 2 services sharing the port. What I am trying to do is forward 443 requests to another port where the SSL service is running so I can hide my port number in the URL.
In the firewall, I opened port 5900 for TCP traffic. Now the console is displaying packet information whenever a connection is made. Why does it send a message to stdout/stderr for an allowed connection? How can I stop it? Logging level is set to critical only, and not-accepted packets should only be logged for the internal and DMZ zones.
Well, as many proxy applications, GNOME Network Proxy Preferences only allow to ignore hosts. What I want to do is exactly the opposite. I only want to use the proxy for few sites. Is it possible to define only the allowed hosts in any way?
PS: I know FoxyProxy add-on for Firefox does this, but 1)I don't use Firefox and 2)I want the proxy settings system wide not only for browser.
I use Ubuntu 10.10 with encrypted home. I'm new with apparmor. My firefox-3.6.13 is now in enforce mode - with standard profile. With this profile it should have write access only to: owner @{HOME}/Downloads/* rw,
But I can save files (with standard downloadmanager of firefox) e.g. in $HOME itself and I can't find any other rule, which could allow that. I have thing, that ecryptfs workaround just affects the eCryptFS "part of things" and limitations of normal filenames/paths (in mounted ecryptfs) are still possible. Why can firefox write elsewhere as in to ${HOME}/Downloads? I get also this in kern.log (but not by saving a file as wrote above):
Why do firefox try to write to it and why do it fail even with #13 workaround? Feb 27 06:03:23 duron650 kernel: [ 3118.231818] type=1400 audit(1298783003.534:49): apparmor="DENIED" operation="open" parent=1782 profile="/usr/lib/firefox-3.6.13/firefox-*bin" name="/tmp/.X0-lock" pid=2304 comm="firefox-bin" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0 Why try firefox to access X lock?
sudo ssh -L 750:192.168.123.103:873 username@192.168.123.103It does exactly what it's supposed to do, but how do i edit / remove this rule?Is there some config file where i can alter the forwarding? How does it get stored?Im using Ubuntu 10.10Server Edition (allthough i recon it would be pretty much the same across all versions
I have the Shorewall firewall running on Ubuntu 10.10 server and the issue I am having is the firewall is blocking traffic from my transmission-daemon even though I have allowed it in the /etc/shorewall/rules.
as you can see, Shorewall is rejecting packets with source and destination port 51413 on incoming net2fw and outgoing fw2net even though the rules are set to accept.
I am using FF ver 5.0.1 from here After reading [URL] I did Code: sudo aa-logprof /path to firefox Allowed all when asked. But when I try to start FF in enforce mode I get
Is there any way to verify if packets being trafficked over a certain port are valid for the service you want to use this port for?
One obvious example that probably clarifies my question: When I open port 443 (outgoing or incoming) for https/ssl traffic, I don't want this port to be used for say openvpn traffic. Thus: when someone wants to surf to a website with https, it should be ok but if someone wants to connect to his home openvpn server over that same port, it should be blocked.
I'll explain this in one sentence: Is it possible to program a port-binding shellcode in which people across the Internet can connect to, without being thwarted by the router blocking their data because the port its bound to doesn't allow port-forwarding
As it stands I have a small home network operating behind my modem/router. Some of the ports on this are forwarded to my PS3 for gaming but I was looking at forward some for my file server.
At the moment I've forwarded port xxx22 to port 22 on my server for SSH for instance. ANd similarly 21 for FTP (although it doesnt seem to want to connect for any more than a few seconds using that). What I was thinking of doing was placing a small website for a handful of ppl to use on the server too and port forward again - xxx80 to 80. It works just fine but I'm a little concerned on the security front.
As I've moved the port to something different from the outside world I'm presuming I will have already cut the potential for malicious folks to wander in but is there anything else I should be doing? At the moment there's no firewall operating on the server, usually as its hidden behind the modem/router. But if I open this thign up more permanently what should I be doing? I've read a few articles on it but I'm always left with the overwhelming thought of "Thats if theres no firewall in my router" as they just seem to do the same.
I live in a campus & I use wifi...I know the server host IP but dont know ftp port number....so I can not open ftp pages through google chrome as I cant specify the port number. Is there any way to know the port number?
I'm new to linux, but enjoy using it very much, especially without a GUI, console is fun! I need to set up port forwarding. We have 3 servers, 1x running Ubuntu server 8.04 (used as transparent proxy), 1x server 2003, 1x windows xp.
The linux box has the following ips: eth0 (internal) 192.168.1.5 eth1 (external) 192.168.0.7
Windows server 2003: 192.168.1.6
Windows XP: 192.168.1.9
Router: 192.168.0.1
The router automatically forwards specific ports to 196.168.0.7 (Linux eth0). From there I want to forward port 8585 to 192.168.1.6 and 3000 to 192.168.1.9. Is there a way that I can do this using iptables?
The commands that I think I'm gonna use look like this: iptables -A FORWARD -s 192.168.0.0/24 -p tcp --dport 8585 -d 192.168.1.6 -j ACCEPT iptables -A FORWARD -s 192.168.0.0/24 -p tcp --dport 3000 -d 192.168.1.9 -j ACCEPT
Would this be a correct way of doing it? My biggest problem is that I can't test it without going live, and if I go live and something doesn't work, the entire building will be left without internet, people will hate me. Also, The proxy captures all data on port 80 and forwards it to 3128 so that the proxy can monitor the usage, and a few systems runs fine with it, others however can ping websites, and internet explorer says "website found, waiting for reply" but the webpages cannot be displayed.
In order to connect to the internet when i am at work i have to use a proxy server; the problem is that this proxy also blocks port xxxxx which is used by a internet radio station. Is there any way to be able to listen to that radio station?
i have a proxy server up and running but one server using port 8181 cannot be accessed.how i can open that port!...i tried adding it in the safe ports but it still isn't working...
I have got a reverse proxy that is working just fine, it accepts requests on port 443 and port 80 and ONLY sends traffic upstream to port 80 to the apache server listening on localhost. I use the following config:
My problem is the following : The site should act differently in some occasions based on whether http or https was requested. So my idea is to setup second http vhost on apache listening to port 8080 and on that vhost I would server the https code. So is it possible to use SQUID to :
Send traffic destined for port 443 to localhost:8080 and Send traffic destined for port 80 to localhost:80 ?
My college providers shifted to a different setting.. I'm not sure what needs to be done. On windows, under the connections tab you need to change the proxy settings and put in the IP address and enter the port to 3000. Questions:
1. where lies the linux (ubuntu 10.04) variant to execute the operation.
2. What can be the major obligations of such a change?
I am sure its siimple enough, but I can't get my net to work properly. The connection provided to the internet is through wireless routers.
I am using VirtualBox as virtualization machine. My topology is:Quote:Internet=====(eth0)HostOS=SLackware(eth1,br0)=====(eth0)GuestOS=slackwareCondition each OS:
Here is my network diagram ADSL router----firewall--LAN inside the LAN my squid is running. currently all users are working with out proxy server. I installed the proxy server inside the LAN. now all users can access web browsing ,but no other ports are working , like POP3, smtp, then some other TCP port based applications are not working. My firewall ( juniper) is created and tested the rules to allow the POP3 and smtp and selected poprts which is working , but I redirected through squid proxy server the clients are not able to access. where do I have to create rules?
** in squid proxy( i already did in safe port list stillnot working) ** IP tables?
I have just installed Squid proxy. i also use WPAD to deploy policies for all client. Both works well together. Now i want to configure firewall Juniper SSG140 will be deny all request from client to access internet and redirect to Squid. I mean deny HTTP & HTTPS except Squid (port 3128), even i want to all access to internet have to through Squid proxy. I don't expert about the firewall Juniper. May i know step by step configure it.
When i click preferences-network proxy a screen of comes up showing the system internet configuration. Is there a way to make all system connections got through tor?
I am trying to install a proxy on my Kubuntu 10.10, since I live in a country that blocks access to almost everything. I tried to install squid, anon, socks.. both with command-line and KPackageKit, but every time, I have this error message:
Rather than use pfsense, etc I decided to create my own router/proxy etc based on an atom base with 2 nics.Proxy/routing/dns/etc all working fine, I now though want to lockdown the fw rules.ETH1 is the WAN NICETH2 is the LAN NICI'm guessing i want to allow anything out of ETH1, but only allow incoming to ETH1 when its established or related... What about ETH2 though? Any ideas pls? Am used to configuring iptables on single nic, certainly not a router.
Code: Chain INPUT (policy ACCEPT 18535 packets, 10M bytes) pkts bytes target prot opt in out source destination
