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hello all<br />
<br />
i guess the topic is pretty much self explainatory : i'm trying to filter dns notifications with ipfilter<br />
<br />
so far i tried a bunch of stuff such as the following without success<br />
-A INPUT -p udp -m udp --dport 53 -d 127.0.0.5 ! -f -m u32 --u32 &quot;0&gt;&gt;22&amp;0x3C@8&gt;&gt;16&amp;0xF=0x4&quot;<wbr /> -j REJECT --reject-with icmp-port-unreachable<br />
<br />
if there is a different way with a different module, i'll be glad to accept the answer<br />
<br />
i'm not interested in suggestions using a different firewall or a separated application<br />
<br />
thanks for your help
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</div>


hello all

i guess the topic is pretty much self explainatory : i'm trying to filter dns notifications with ipfilter

so far i tried a bunch of stuff such as the following without success
-A INPUT -p udp -m udp --dport 53 -d 127.0.0.5 ! -f -m u32 --u32 "0>>22&0x3C@8>>16&0xF=0x4" -j REJECT --reject-with icmp-port-unreachable

if there is a different way with a different module, i'll be glad to accept the answer

i'm not interested in suggestions using a different firewall or a separated application

thanks for your help

iptables/netfilter u32 module match dns OPCODE = notify

Networking is the process of connecting computing devices, peripherals and terminals together through a system that uses wiring, cabling or radio waves that enable their users to communicate, share information and interact over distances. Often associated are issues regarding operating systems, hardware and equipment, cloud and virtual networking, protocols, architecture, storage and management.

Networking

Virtualization is the act of creating a virtual (rather than actual) version of something, including (but not limited to) a virtual computer hardware platform, operating system (OS), storage device, or computer network resources. Virtualization is usually the creation of a system that executes separate from the underlying hardware resources, or the creation of an entire desktop for systems located elsewhere, similar to thin clients.

Virtualization

Networking software modules are interfaced with a framework implemented on the machine's operating system that implements the networking functionality of the operating system. The best known frameworks are the TCP/IP model and the OSI model. Systems typically do not use a single protocol to handle a transmission. Instead they use a set of cooperating protocols, sometimes called a protocol family or protocol suite.[9] Some of the best known protocol suites include: IPX/SPX, X.25, AX.25, AppleTalk and TCP/IP. Other protocols indirectly related to networking include the hypertext transfer protocol (HTTP) and its related technologies, Dynamic Host Configuration Protocol (DHCP), Domain Name Server (DNS) and other Internet protocols.

Networking Protocols

Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.