I am using squid on my fedora box as a proxy server.By default the iptables (Firewall) service is on.To allow web pages to my client machines i stop the iptable service.
#service iptables stop
By doing it client computers start browsing.kindly how can I add a rule so that without stoping firewall client compter work fine.my perver IP address is 10.1.80.10
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?
I guess this is the right place to put questions about iptables, so forgive me if it is not.I have a MySQL database which I need to allow connections to: 1 - the internal network; 2 - the web server (Apache) connections;3 - A user who is out of this network in a range of dynamic IP.Let's suppose the range IP for this user is 179.4.247.0-179.4.247.254 and the server; where is MySQl and Apache is 60.22.30.232. This user will use the windows client MySQL tool to make connections into this database.
So I think these rule below allow connections to the internal network and apache:
iptables -A INPUT -i eth0 -m state state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -i eth1 -m state state ESTABLISHED,RELATED -j ACCEPT
[code]....
My firewall , wich is an Ubuntu server 10.10 , have 3 interfaces:
eth0(192.168.0.254):linked to the DMZ
eth1(192.168.1.254):linked to the LAN
eth3(212.217.0.1):linked to the Internet
-The DMZ have one web server with a static address (192.168.0.1).
-My LAN address range is (192.168.1.2-192.168.1.100) managed by a DHCP server in the same firwall machine.
There are some of the rules that I need to set up :
-Allow HTTP between the LAN and the internet
-Allow HTTP between the web server in the DMZ, and the internet.
Is there a way to tell the firewall , to redirect all incoming HTTP requests only to the web server in the DMZ ?
I'm not an iptables expert. Anybody know how to create a rule/chain that will log info similar to what tcpdump -s0 would do?
View 3 Replies View Relatedhow can i drop igmp port 0 packets with iptables rule? my log file is full of this router advertisement.
View 2 Replies View RelatedThe iptables has every rule set correctly, the users in the subnet works great, but I have the following issue.every user connect to a mysql running on the internet through the port 3306, the forward and masquerade do the job. Now I have a user in the outside, and he wants to connect to a mysql in a certain machine (Not the gateway), prerouting rules solve my problems, but all the packages from the inside users goes now to that certain machine. I would like something like if the package passed trough masquerade don't pass trough the prerouting rule, and if it come from the outside (Not a package that come from a petition from the inside) pass trough the prerouting rule.
View 6 Replies View RelatedDoes anybody know how to block HotSpotShield in squid or iptables?
View 2 Replies View Relatedi've got a software that uses a specific tcp port e.g 11111. i want to redirect all the traffic from 11111 to squid port 3128. i'm using the following commands to redirecting:
iptables -t nat -A PREROUTING -p tcp -m tcp -i eth0 --dport 11111 -j DNAT --to 192.168.0.1:3128
iptables -A FORWARD -p tcp -m tcp -i eth0 --dport 11111 -j ACCEPT
my ubuntu server has two interfaces. eth0 is for local network (dhcp assigns ips) and eth1 is for internet. my ubuntu server acts as a gateway and as an authentication server for users.
at squid also i have the following configuration regarding my port:
acl myport port 11111 http_access allow CONNECT myport. my squid installation is not transparent as users need to authenticate in order to access the web.
my application is a windows application and of course is not working. i examined the packets with wireshark and i noticed that when the program tries to access the internet, squid replies with err_invalid_request (the packet contains that data). the program is trying to send some plain text via port 11111 and as far as i can image, somehow squid declines the data. i cant get rid off squid as i want to pass the traffic from squid. what is the problem?
i have the following ip assignments
fedora (iptables)
eth0 -private :192.168.1.1
eth1 -public : 186.117.50.6
squid proxy
192.168.1.10:3128
my clients range
192.168.2.0/24
how can i make my clients to browse internet only from proxy server my network is NAT 'ed. Please specify a iptable rule to allow internet access for my clients to browse ONLY if they come through proxy server.
i'm new in linux world i would like to know how can i add the rtp protocol to my iptables rule for Netfilter firewall,but without installing the asterisk server
View 1 Replies View RelatedUnsure about IP tables lingo, so excuse me for not looking this up:I have a server, running IP tables, that I do not want to allow any type of outgoing traffic to 192.168.1.21
View 3 Replies View RelatedI'm looking for a way to add a rule that would whitelist my ip address when I login with SSH. I can grab the IP out of the SSH_CONNECTION variable, however I'm not sure how I could add it into iptables with my non-root privileged user. I've got root access, but I want the process to be automatic. I considered sudo, however I don't want normal users to be able to modify anything about iptables, though perhaps there is a trick about it that I don't know which would only allow it in the /etc/profile or the like
View 3 Replies View RelatedDo I have to create a rule for:
Code:
$IPT -A fwalert -p tcp --tcp-flags SYN,ACK SYN,ACK -m conntrack --ctstate NEW $RLIMIT -j LOG $LOGLIMIT --log-tcp-options --log-level 4 --log-prefix
to drop rather than log if my table has a default policy of drop with :
Code:
$IPT -t fwalert -P DROP
Loaded up Centos 5.5 final. Configured iptables to block regions of the world based on networks. An example would be:
-A INPUT -s 139.82.0.0/16 -j DROP
My /etc/sysconfig/iptables file contains about 10k entries like this. If I use this, the machine lags hardcore network wise.
This isn't exactly of critical importance, but is there any way to block two entirely different addresses in the one rule, rather than writing individual rules for each of them? For example, if the addresses were 1.1.1.1 and 8.8.8.8, and I only wanted to block these two.
Or alternatively, if I wanted to block two subnets, say 1.1.1.0/24 and 8.8.8.0/24? Can this be done in one rule?
my iptables Policy is Drop..my server ports is open just for httpd,ssh .Is there any rule which can allow all connection from a specific program for ex. i want to scan an ip Address ports.as you know nmap connect to every known port to see if that is open or not so, if i want to allow nmap to connect, i need to include all ports for that, or i can allow connection from localhost to outside in all ports .my server is very secure . i dont want other programs (probably a backdoor) use those ports to connect outside i want to know is there any ability in iptables which can rule connections by name of program like "Allow any Connection from /usr/bin/nmap to everywhere " ?
View 2 Replies View RelatedI have configured a sendmail MTA for incoming mails in a network and by using IPtables i have redirected the traffic internally to other port where one more SMTP by a application is running.Iptables rule:iptables -A INPUT -i eth0 -p tcp --dport 25 -j ACCEPTiptables -A PREROUTING -t nat -i eth0 -p tcp --dport 25 -j REDIRECT --to-port 25000My sendmail config is as below.
Sendmail.mc
define(`SMART_HOST', `relay:host.subdomain.mydomain.com')dnl
dnl # define(`RELAY_MAILER',`esmtp')dnl
[code]...
I am new to iptables. The setup tool on a VPS doesn't work. So, I am learning to insert rules. I have inserted so many and some of them show as duplicates now.
1- I want to know how to remove the duplicates. Is there a file that these rules are store in so I can go in and easily edit it?
2- Is there any other utility that handles firewall in Linux that I am unaware of? or is the iptables the ultimate door guard? This is a plain install of CentOS.
3- Since I believe I opened port 5090 but I think it still might be blocked, could SELINUX be the problem? How can I get my way around setting it to permissive or disable if I don't have access to "setup" command?
4- What is the order of iptables reading? does rule #1 supersede all other rules? or does the last rule supersede all rules prior to it?
5- Do the rules below make a fairly safe system? (except for the duplicates which should be remove) I understand that a safe system is dependent also on the applications that are allowed in this category and I am not talking about those. I am talking about dropping all other inquiries and in general is this how iptables are setup? This is what I currently have:
[root@tel ~]# service iptables status
Table: filter
Chain INPUT (policy ACCEPT)
num target prot opt source destination
[Code]...
Trying to setup my box as a router on Ubuntu 10.04. When trying to setup a NAT rule in iptables 1.4.4 like so:
Code:
sudo iptables --table NAT --append POSTROUTING -o eth0 -j MASQUERADE
I keep getting:
Code:
Can't initialize iptables table 'NAT': Table does not exist (do you need to insmod?)
Looking at lsmod, it doesn't look like I have anything NAT related loaded ( I just have iptable_filter, ip_tables, and x_table ). Doing a locate nat, I find a module that looks like it should work. I'm running 10.04.1 LTS - Kernel is 2.6.32-25-generic #45-Ubuntu SMP and it is pretty much stock - haven't done anything fancy... this module looks promising:
Code:
/lib/modules/2.6.32-25-generic/kernel/net/ipv4/netfilter/iptable_nat.ko
but loading it and I get:
Code:
-1 Unknown symbol in module
Currently I'm looking into implementing mod_security on all our apache servers. The installation on CentOS 5.5 comes directly with the "Core Rule Set" by the mod_security devs (curiously Debian and Ubuntu do not carry these) They also offer the Enhanced Rule Set for mod_security in a commercial package [URL] The main point there in their info link is the first point
Quote:
Tracking Credit Card Usage as required by the Payment Card Industry Data Security Standard However acc. to this wiki article ( http://en.wikipedia.org/wiki/Payment...urity_Standard ) that specific requirement isn't stated anywhere, as well as my colleague who's working on the PCI-DSS compliance for our code/servers/etc. mentioned that he hasn't heard of this specific requirement either. So my question would be if anyone has any experience with their ERS package and if it's needed for the PCI-DSS compliance compared to the requirements given in bullet points @ wiki article.
i have set firewall for centos of 192.168.1.21 server like this.
it has a gateway of 192.168.1.2
iptables -P INPUT DROP
iptables -A INPUT --in-interface lo -j ACCEPT
iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
iptables -A INPUT -p tcp --destination-port 22 -m mac --mac-source 00:0F:EB:91:00:01 -j ACCEPT
iptables -A INPUT -p tcp --destination-port 80 -m mac --mac-source 00:0F:EB:91:00:01 -j ACCEPT
the mac source is my laptop's mac address. But when i try to ping from my laptop of 192.168.0.2 (my gateway is 192.168.0.1 but share the same server that has 3 network gateway including gateway for the centos)it failed. what i should do to enable this ping.i also cannot connect to the centos server unless i change my ip to 192.168.1.x and same gateway as centos.can someone suggest what should i modify my firewall to enable connection to centos server from my 192.168.0.2 laptop? is that related to nat and forward chain in firewall of centos?
is someone can guide the best open source tools to monitor as webbase,gui,shell prompt
View 1 Replies View RelatedWhat is the best IPtables configuration for bind DNS server.
View 3 Replies View RelatedI'm using iptables with modules ip_contrack_ftp to be able to use passive ftp. It works well as long as port 21 is being used as listening port. Is there any way to make it work when I configure my ftp server (vsftpd) to listen on an alternative port, lets say 21001 or something? The helper module only seems to be working properly with the standard port, so I was wondering whether there was a way to "tell it" that another port is being used? I mean, of course I make a rule in fw to allow traffic to the alternative port.
But once it's time to start passive connection, then the iptable module cannot handle it properly. I could solve the problem by making a range of passive ports in the ftp-server configuration and allow the incoming traffic to them, but then using helper modules doesn't make any sense. I just want to allow the traffic to the listening port and then want the ip_contrack_ftp module to take care of the rest. This is what I do today - but only port 21 seems to be working. Is there a way to do this with a non-standard ftp port?
I have setup a squid server on Rhel5.4. I would like to know how I can configure my squid server to block anon proxy sites.
View 3 Replies View RelatedI have been struggling with this for a very long time now. I have installed Fedora Core 9 on my computer. I have set it up as a caching-nameserver and this is working.
Then I wanted to secure my server with iptables, and I have so far made this script:
# Load the connection tracker kernel module
modprobe ip_conntrack
iptables -F
iptables -P INPUT DROP
iptables -P FORWARD DROP
[Code]....
I can reach the dns server with ping. When trying Nslookup it says that it got SERVFAIL from 127.0.0.1 trying next server, and then it times out.
My resolv.conf file lists:
nameserver 127.0.0.1
nameserver DNS-server
Im pulling my hair out trying to get ftp to work through iptables.Im using vsftpd
Table: filter
Chain INPUT (policy DROP)
num target prot opt source destination
1 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
2 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED
[code].....
What i wanted to do was block everything from getting in my pc but still be able to surf the web and still use instant messenger.
View 2 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.