so the firewall rules I am currently using are displayed below.
Code:
# DROP ALL FORWARDED PACKETS
iptables -P FORWARD DROP # DROP ALL PACKETS
# ALLOW DHCP THROUGH THE FIREWALL
[code]....
I added a few rules to my /etc/iptables.rules file and then used sudo iptables-restore < /etc/iptables.rules but i got an error saying "iptables-restore: line 29 failed".But the only word on that line.
View 1 Replies View RelatedI am trying to program iptable rules for implementing a 1:1 NAT which does the following:
1. Forward all traffic from all ports on a public ip to a private ip
2. Forward traffic from a range of ports (x-->y) on a public ip, to a private ip
I did some google searches for the same, and came up with the following.
iptables -A FORWARD -t filter -o eth0 -m state
state NEW,ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -t filter -i eth0 -m state
state ESTABLISHED,RELATED -j ACCEPT
Can someone please let me know strong iptables rules? Below entries are in iptables file.Here Y.Y.Y.Y is another branch public IP.This server acts as gateway+squid server.Further it will serve company's intranet page also using httpd.OS is CentOS 5.0.
View 1 Replies View RelatedI am setting my firewall rules using the command iptables.My question is i wanna know what command i can use that list rule 2 and 3 for instance in my table?i want to create rule that: The host is administered using SSH, scp and sftp so allow incoming SSH traffic and securing remote file copying and transferring.
View 2 Replies View RelatedWhen I use system-config-firewall, it asks what interfaces to trust. Where does it store that information for iptables (or whatever uses that info)? How iptables knows at what interfaces to use the rules?There is not that kind of information in /etc/sysconf/iptables and iptables-config.
View 2 Replies View Relatedwhat do the following two commands do? Do they modify the iptables rules in any way?
sudo /sbin/iptables -L -n
sudo /sbin/ip6tables -L -n
I need with some iptables rules. I've done all I can, Googling all over, to cover as many exploits as possible and the following script is what I've come up with. The current set up works and I've checked with NMAP. I just need some sort of confirmation that this is pretty much what I can do.
Code:
LAN="eth0 eth1"
RANGE=10.1.0.0/17
WAN=eth2
# Delete all existing rules
[code]....
Also, if I wanted a broadcast to be relayed to all subnets within a defined range, how would such a iptables rule look like? I need this in order to find a networked Canon MP640 printer.
I put together the following filter set :
Code:
#!/bin/sh
#To understand this script, reference the No Starch Press Linux Firewalls Book.
MODPROBE=/sbin/modprobe
IPT=/sbin/iptables
IPTSV=/sbin/iptables-save
IPT6=/sbin/ip6tables
IPT6SV=/sbin/ip6tables-save
### flush / drop policy sets
echo "[+] Flushing existing rules with DEFAULT of DROP [+]"
echo "[+] IPv4 [+]"
$IPT -F
$IPT -F -t nat
$IPT -X
$IPT -P INPUT DROP
$IPT -P OUTPUT DROP
$IPT -P FORWARD DROP
echo "[+] IPv6 [+]"
$IPT6 -F
$IPT6 -F -t nat
$IPT6 -X
$IPT6 -P INPUT DROP
$IPT6 -P OUTPUT DROP
$IPT6 -P FORWARD DROP .....
###OUTPUT rules: LOG rule
$IPT -A OUTPUT -o ! lo -j LOG --log-prefix "DROPED OUTBOUND" --log-ip-options --log-tcp-options
I wanted to know how to allow certain applications through the outbound tables. For example, I wish to be able to use tools such as nmap,tracepath, and traceroute. However, I am not sure where to look to understand the ports to open. I was starting to think that maybe rather than ports to open it would need to be somehthing like tcp flags that would ned to be allowed. Any way, I have tried google and am still haing problems. I started wanting to use these tools due to getting ready for my network+ and security+ certs.
I have been trying to figure out how to makes rules in iptables that expire after a certain amount of time. From what I have found online you want to use the recent module with --rcheck and --seconds. I have found a few examples and have given them a shot but I can't seem to get it right. Would anyone mind posting an example of a rule that will auto expire?
View 3 Replies View RelatedI've configured squid proxy server in a P4 desktop. I've 50 users in my network. I installed RHEL 4.4 (2.6.9-42 kernel) and the iptables version is 1.2.11-3.1. I've 2 NICs installed in the system. eth0 (192.168.100.99) for local lan and eth1 (192.168.1.2) for outgoing to internet. I've connected DSL broadband modem to eth1 (default ip of DSL modem is 192.168.1.1). All the clients except few has been forced to go through squid by user authentication to access internet. Those clients which were kept away from proxy are 192.168.100.253, 192.168.100.97, 192.168.100.95 and 192.168.100.165. Everything works fine but from last week I observed that one of some notorious user use the direct IPs (192.168.100.97 or 192.168.100.95) in the absense of the owner of these IPs to gain access to internet as we applied download/upload restrictions in squid.
I want to filter the packets of source hosts using MAC address in PREROUTING chain. I read somewhere that IPT_MAC module must be installed to make this happen. So that those notorious users can not change their ips to gain direct access to internet.
Below are the contents of my iptables file (I've ommited few entries for safty purpose).
# Generated by iptables-save v1.2.11 on Wed Nov 25 16:35:57 2009
*filter
:INPUT ACCEPT [14274:3846787]
:FORWARD ACCEPT [4460:1241297]
:OUTPUT ACCEPT [16825:4872475]
code....
I was wondering if there is a way to find out IP blocks based on a given region. I know there are IP Lookups that will tell you what Country and possibly City a given IP is from. What I want is the following:
- I would like to set up a IPTABLES rule that implements something like:
=> ALLOW VPN connections FROM THIS ISP/IP BLOCKS THAT ARE IN CITY XYZ
Basically, I want to limit my incoming VPN connections FROM my ISP in the surrounding area. So, for example, I can go to my friends house who also has the same ISP. I should be able to connect from his home to mine because we have 1) same ISP 2) IP blocks is confined to a particular local location.
whether iptables logs can be set to automatically resolve IP addresses? I am running the firewall on a network with DDNS/DHCP, and this ability would really help quickly identify hosts with suspect traffic.Failing this, I guess the simplest solution will be to simply set static addresses!
View 1 Replies View RelatedI have setup my linux fedora server and i want to restrict access to my server.Basically i control using iptables.I'm not sure how to write an iptables rules to control drop all connection to port 8080 and allow only certain ip can access the instance on port 8080 example ip=10.254.14.16,192.168.1.10.
View 3 Replies View RelatedI'm trying to automatically load some iptables rules by adding the below script in the /etc/network/if-up.d directory:
Code:
#!/bin/sh
IPTABLES=/sbin/iptables[code]...............
I've read the instruction about setting up the iptables rules to filter all port except HTTP, SSH, FTP. I require first remove all default iptables rules and set default rules to all chains as DROP:
# Set default-deny policies for all three default chains
$IPTABLES -P INPUT DROP
$IPTABLES -P FORWARD DROP
$IPTABLES -P OUTPUT DROP
Then allow only some ports:
#Accept inbound packets that are part of previously-OK'ed sessions
$IPTABLES -A INPUT -j ACCEPT -m state --state ESTABLISHED,RELATED
# Accept inbound packets which initiate SSH sessions
$IPTABLES -A INPUT -p tcp -j ACCEPT --dport 22 -m state --state NEW
# Accept inbound packets which initiate FTP sessions
$IPTABLES -A INPUT -p tcp -j ACCEPT --dport 21 -m state --state NEW
# Accept inbound packets which initiate HTTP sessions
$IPTABLES -A INPUT -p tcp -j ACCEPT --dport 80 -m state --state NEW
# Log anything not accepted above $IPTABLES -A INPUT -j LOG --log-prefix "Dropped by default:"
But I hired a VPS from other country so the only mean I can manage it is via SSH. If I setup the default rule to DROP first, I afraid that I can no longer connect via SSH to tell iptables allow SSH
So my question is:
- Does the IP tables take effect immediately after I input a rule?
- Is there any mean to run this as a batch job (create a script and run all these rules one time).
- My VPS has a web control panel which have a terminal via web. Is this a native terminal or just a connection via port 80 or 22?
I am setting up tomcat server on my Centos 5.5 machine. I've been advised to run tomcat on 8080 as non root user and redirect traffic to it from port 80.
I searched and found the following iptables commands for this:# iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT -to-ports 8080
# iptables -I INPUT -p tcp --dport 8080 -j ACCEPTI have a doubt:
Tomcat is not accessible via port 80 without the second command. But the second command opens 8080 and makes it accessible over the internet (tomcat is accesible via both: www.<website>.com and http://<ip address>:8080). This doesn't seem right. Is there some simple (iptables) way to redirect traffic "internally" from port 80 to 8080 without having to open 8080 to the internet.
I want to simplify some of my rules, so I want to create rules for certain services like xmpp, web, etc. since some of them use multiple ports, and I toggle them on/off a lot. Can I simply put the jump to rule clauses in the Input chain, and once the sub chains run, does it return to the input chain after the jump to rule clause? I want to do this so I don't have a ton of rules in the input chain. I think that if I simply make a list of all the rules to jump to in the input chain, it will work itself through all of them until it finds a matching filter in one of them correct?
View 9 Replies View RelatedI'm trying to limit access to port 8443 on our server to 2 specific IP addresses. For some reason, access is still being allowed even though I drop all packets that aren't from the named IP addresses. The default policy is ACCEPT on the INPUT chain and this is how we want to keep it for various reasons I wont get into here. Here's the output from iptables -vnL
[Code]...
Note the actual IP we are using is masked here with 123.123.123.123. Until I can get everything working properly, we're only allowing access from 1 IP instead of 2. We can add the other one once it all works right. I haven't worked with iptables very much. So I'm quite confused about why packets matching the DROP criteria are still being allowed.
Question (and Google results aren't making this clear): Ubuntu has both iptables & ip6tables installed. 1. If I set a rule in iptables, does that rule also apply to ipv6, or just ipv4?
2. If "no" to above, then it would be prudent to *also* set ip6tables rules as well if I want to maintain an active firewall, correct?
3. Does ip6tables rules have the same syntax and behavior (more or less) to iptables rules - i.e. can I just copy my iptables rules & change "iptables" to "ip6tables"?
4. Any gotchas or issues that I should be aware of?
IPtables creates an error during startup as well as when I try to restart it: Here's the output of:
[Code]....
I am running Ubuntu server 10.10 and trying to setup iptables rules in /etc/if-up.d/iptables
Quote:
root@host# cat /etc/network/if-up.d/iptables
#!/bin/sh -e
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
Problem is that iptables doesn't get updated and I don't see them when iptables -L is executed after reboot.
my linux box the device node for my printer is by default setup as the following: crw-rw---- 1 root lp 189, 1 Apr 3 07:45 /dev/bus/usb/001/002 This causes cups to not print at all. The Hp backend (HPLIP) fails because of these permissions. How do I change it so that it's crw-rw--rw 1 root lp 189, 1 Apr 3 07:45 /dev/bus/usb/001/002. Ie I would like 666 file permission on that node.
View 2 Replies View RelatedI have a computer with two interfaces (eth0 and eth1), eth0 is connected with a local network and eth1 is connected to the internet, also it implements a NAT in the interface eth1. Nevertheless, I'm trying to create spoofed packets with sockets raw in the computer that runs the NAT and send the packets to the interface eth1. The problem is that the NAT is changing the IP source to the real one before send the packets. So, anyone have any idea how can I implements the NAT in eth1 but only apply the NAT to the packets that are from/to eth0? I was thinking in something like (I am really newbie with iptables):
iptables -t nat -A POSTROUTING -o eth1 -i eth0 -j MASQUERADE
Well, it didn't work.
I just install 1 firewall using Iptables.
Firewall includes 2 NIC:
NIC1 <IP PUBLIC>
NIC2 192.168.10.1
I installed 1 web server IP: 192.168.10.2
I have some PC IP range: 192.168.10.10->20
I set rules NAT on firewall and PC & web server can connect internet good, but I have problems:
When PC access to web server with IP 192.168.10.2 that ok, but PC can't access to web server when using IP Public. But outside internet, I can access to web server using IP Public.
Rules on IPTables
Code:
# Generated by iptables-save v1.3.5 on Sun Mar 7 21:01:16 2010
*nat
:PREROUTING ACCEPT [950:126970]
:POSTROUTING ACCEPT [89:5880]
:OUTPUT ACCEPT [19:1342]
-A PREROUTING -d 209.99.242.124 -i eth0 -p tcp -m tcp --dport 80 -j DNAT --to-destination 192.168.10.2:80
-A POSTROUTING -s 192.168.10.0/24 -o eth0 -j SNAT --to-source 209.99.242.124
*filter
:INPUT DROP [1599:157409]
:FORWARD DROP [0:0]
:OUTPUT ACCEPT [232:34452]
-A FORWARD -i eth0 -o eth1 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i eth1 -o eth0 -j ACCEPT
-A FORWARD -i eth0 -o eth1 -d 192.168.10.2 -p tcp --dport 80 -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth1 -j ACCEPT
-A OUTPUT -o lo -j ACCEPT
-A OUTPUT -o eth1 -j ACCEPT
COMMIT
I'm new to server admin, so my question is based on what may be a bad assumption. With a server, my assumption is "if it ain't broke, don't fix it". In other words, I'm not really interested in upgrading the software to the latest and greatest if I already have stuff working on the server.
However, the one place where I DO want to constantly have upgrades is for security patches. How do I apply security updates to Ubuntu Server... and ONLY security updates?
I want to use iptables to automatically block all IP addresses who send UDP packets with length 11 more than 3 times per 10 seconds.
View 1 Replies View RelatedI'm having some trouble with the configuration of the iptables. I want to setup a network server to serve as Fail Over (for my 2 ISPs), DHCP and DNS. I have 3 network cards, 2 connected to ISP's routers and 1 that serves as UPLINK for my switch.
I want to add some Iptables rules so I can achieve what I want to do. The problem is that the rules I try to use, they have to effect.... they don't load, here are the rules I am trying to add:
#iptables --table nat --append POSTROUTING --out-interface eth1 -j MASQUERADE
#iptables --table nat --append POSTROUTING --out-interface eth2 -j MASQUERADE
#iptables --table nat --append POSTROUTING --out-interface eth2 -j SNAT --to EXTIP
When I try to check to see if it loads, with the command:
#iptables -L
It returns empty
I am trying solve a strange problem which ocurred after upgrading many packages including kernel and iptables.This is a Fedora 10 PC acting as a small home-server I've been using over a year without problems. Recently, I've run a yum upgrade and after that, connections outside home wouldn't work. No changes in IPtables (firewall) rules have been done. But connection through local network is working.Symptom is.I've connected to my second PC at home and connected to the server. It works fine on local network. I restart network services (service network restart) and outside connections could be established.I have disabled iptables and ip6tables and after reboots it works fine. But PC is running without firewall.
View 5 Replies View RelatedI set up a squid transparent proxy and I have a problem with an iptable rules. I have a rule to redirect all request to port 80 to go on port 3128. To do so, I'm using this iptables command :
Code:
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 3128
This command is working like a charm. The only problem is, for some unknown reasons, this rule will be dropped at some point. I did not manage to identify what is causing this to happen. It occurs during night, but I have nothing about that in my log files. messages / firewall / ...) The only way I managed to reproduce this 'dropping' is this one: I type the command like as root. The command is effective and working fine. I open yast, I go to the firewall module, the I do a simple "save changes and restart firewall" (without changing anything). As soon as this process is finished, the iptables rule is gone.
-How can I make this rule permanent ?
-Is there a place where I can launch a script executing this rule, after the yast firewall module is 'touched' or something ?