Hi, I'm trying to find a way to protect my network against arp spoofing.
What it is:
An attacker sends fake arp packets in the network, identifying himself as the router. All network traffic is then redirected to this attacker.
How to protect myself:
In my opinion, the best possible protection is arptables firewall running on my router. But I'm not sure hot to set it up properly. It sholud be simillar to iptables, so I tried:
So all arp packets are dropped (default policy DROP, first two lines) and only those coming from or to my router (= valid ones) are allowed.
But for some reason, my whole network collapses after executing this command. Any idea what is wrong?
Last edited by DukeNuke2; 01-01-2012 at 01:01 PM..
There is a program that I am trying to run on a shell account. It depends on another program, which I have also copied to the shell account. Both are in my home directory, yet the first program has a different path hardcoded into it, which I cannot use because of permissions problems.
How can I... (3 Replies)
Hi, I am currently using Mailx to send a mail message from my unix account via an SMTP relay. This is working ok.
However from the recipient end the FROM address they see on mails received is <unix account>@<domain> eg prod@liveserver.com
Is there anyway I can spoof this FROM address from the... (1 Reply)
Hello all, i need your quick help. I have assignment project class to make a program using pcap library to spoofing DNS in linux environment. Can anyone help me, because i'm newbie in network security and in C?:confused:
Regards,
ptrfw (1 Reply)
There is a question in the SCO section asking for information on how to change the MAC address of a NIC. Is there a valid reason for wanting to change the MAC address? (1 Reply)
Hi everybody!
I'm facing a problem and I doubt about the solution (I'm not very familiar with old *NIXs).
An external network supplier (let's call them "telco") just installed new communication components that filters MAC addresses.
I have a Solaris 5 server, with 1 NIC (hte0) which is... (6 Replies)
I tried to use the command
sudo ifconfig en0 ether xx:xx:xx:xx:xx:xx
to do mac spoofing for internet connection in my office. It works only for 5 minutes. Every time after about 5mins, the Internet will be disconnected. :wall:
Any one knows how to solve this problem? Thanks. (6 Replies)
I have a machine (IP:192.168.1.185) and i want to send spoofed IP address (e.g. 192.168.1.212) to another machine(192.168.1.213) . I am using a spoofing program for this which uses raw sockets.
Now whenever i pass the parameters(spoofed ip addr and destination) to the output of the program, i... (2 Replies)
Discussion started by: syncmaster
2 Replies
LEARN ABOUT NETBSD
arpintr
ARP(9) BSD Kernel Developer's Manual ARP(9)NAME
arp, arp_ifinit, arpresolve, arpintr -- externally visible ARP functions
SYNOPSIS
#include <netinet/if_inarp.h>
void
arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa);
int
arpresolve(struct ifnet *ifp, struct rtentry *rt, struct mbuf *m, struct sockaddr *dst, u_char *desten);
void
arpintr();
DESCRIPTION
The arp functions provide the interface between the arp module and the network drivers which need arp functionality. Such drivers must
request the arp attribute in their "files" declaration.
arp_ifinit() Sets up the arp specific fields in ifa. Additionally, it sends out a gratuitous arp request on ifp, so that other machines are
warned that we have a (new) address and duplicate addresses can be detected.
You must call this in your drivers' ioctl function when you get a SIOCSIFADDR request with an AF_INET address family.
arpresolve() is called by network output functions to resolve an IPv4 address. If no rt is given, a new one is looked up or created. If
the passed or found rt does not contain a valid gateway link level address, a pointer to the packet in m is stored in the route
entry, possibly replacing older stored packets, and an arp request is sent instead. When an arp reply is received, the last
held packet is send. Otherwise, the looked up address is returned and written into the storage desten points to. arpresolve()
returns 1, if a valid address was stored to desten, and the packet can be sent immediately. Else a 0 is returned.
arpintr() When an arp packet is received, the network driver (class) input interrupt handler queues the packet on the arpintrq queue, and
requests an arpintr() soft interrupt callback. arpintr() dequeues the packets, performs sanity checks and calls (for IPv4 arp
packets, which are the only ones supported currently) the in_arpinput() function. in_arpinput() either generates a reply to
request packets, and adds the sender address translation to the routing table, if a matching route entry is found. If the
route entry contained a pointer to a held packet, that packet is sent.
SEE ALSO ether_ifattach(9)
Plummer, D., "RFC826", An Ethernet Address Resolution Protocol.
STANDARDS
RFC 826
HISTORY
Rewritten to support other than Ethernet link level addresses in NetBSD 1.3.
AUTHORS
UCB CSRG (original implementation)
Ignatios Souvatzis (support for non-Ethernet)
CODE REFERENCES
The ARP code is implemented in sys/net/if_arp.h, sys/netinet/if_inarp.h and sys/netinet/if_arp.c.
BSD March 3, 1997 BSD