Free packet loss software software for linux

Packet Garden is a project that allows you to grow a world from network traffic.

Packet Garden captures information about how you use the internet and uses this stored information to grow a private world you can later explore.

To do this, Packet Garden takes note of all the servers you visit, their geographical location and the kinds of data you access.

Uploads make hills and downloads valleys, their location determined by numbers taken from internet address itself.

The size of each hill or valley is based on how much data is sent or received.

Plants are also grown for each protocol detected by the software; if you visit a website, an HTTP plant is grown. If you share some files via eMule, a Peer to Peer plant is grown, and so on.

Net::Packet::CDP::TypeSoftwareVersion is a Perl module for Cisco Discovery Protocol Software Version extension header.

SYNOPSIS

use Net::Packet::Consts qw(:cdp);
require Net::Packet::CDP::TypeSoftwareVersion;

# Build a layer
my $layer = Net::Packet::CDP::TypeSoftwareVersion->new(
type => NP_CDP_TYPE_SOFTWARE_VERSION,
length => 8,
softwareVersion => GGGG,
);
$layer->pack;

print RAW: .unpack(H*, $layer->raw)."n";

# Read a raw layer
my $layer = Net::Packet::CDP::TypeSoftwareVersion->new(raw => $raw);

print $layer->print."n";
print PAYLOAD: .unpack(H*, $layer->payload)."n"
if $layer->payload;

This modules implements the encoding and decoding of the Cisco Discovery Protocol Software Version type extension header.

Packet filtering setup script by Anthony C. Zboralski. Adapted by Didi Damian for iptables version 1.0.0

Sample:

PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

# Set up variables
EXT_IF="eth0"
INT_IF="eth1"
EXT_IP=24.x.x.x/32
INT_IP=192.168.0.1/32
EXT_NET=24.x.x.0/24
INT_NET=192.168.0.0/24
MASQ_NETS="192.168.0.0/24"
LOCAL_ADDRS="127.0.0.0/8 192.168.0.1/32 24.x.x.x/32"
MAIL_RELAY=24.x.x.x/32
SMB_ACCESS="192.168.0.2/32"
SMB_BCAST="192.168.0.255/32"

# Turn on IP forwarding
echo Turning on IP forwarding.
echo 1 > /proc/sys/net/ipv4/ip_forward

# Load the ip_tables module
echo Loading ip_tables module.
/sbin/modprobe ip_tables || exit 1
# I let the kernel dynamically load the other modules

echo Flush standard tables.
iptables --flush INPUT
iptables --flush OUTPUT
iptables --flush FORWARD
echo Deny everything until firewall setup is completed.
iptables --policy INPUT DROP
iptables --policy OUTPUT DROP
iptables --policy FORWARD DROP

CHAINS=`iptables -n -L |perl -n -e /Chains+(S+)/ && !($1 =~ /^(INPUT|FORWARD|OUTPUT)$/) && print "$1 "`
echo Remove remaining chains:
echo $CHAINS
for chain in $CHAINS; do
iptables --flush $chain
done
# 2nd step cause of dependencies
for chain in $CHAINS; do
iptables --delete-chain $chain
done

for net in $MASQ_NETS; do
# I delete all the rules so you can rerun the scripts without bloating
# your nat entries.
iptables -D POSTROUTING -t nat -s $MASQ_NETS -j MASQUERADE 2>/dev/null
iptables -A POSTROUTING -t nat -s $MASQ_NETS -j MASQUERADE || exit 1
done
iptables --policy FORWARD ACCEPT

# Create a target for logging and dropping packets
iptables --new LDROP 2>/dev/null
iptables -A LDROP --proto tcp -j LOG --log-level info
--log-prefix "TCP Drop "
iptables -A LDROP --proto udp -j LOG --log-level info
--log-prefix "UDP Drop "
iptables -A LDROP --proto icmp -j LOG --log-level info
--log-prefix "ICMP Drop "
iptables -A LDROP --proto gre -j LOG --log-level info
--log-prefix "GRE Drop "

iptables -A LDROP -f -j LOG --log-level emerg
--log-prefix "FRAG Drop "
iptables -A LDROP -j DROP

# Create a table for watching some accepting rules
iptables --new WATCH 2>/dev/null
iptables -A WATCH -m limit -j LOG --log-level warn --log-prefix "ACCEPT "
iptables -A WATCH -j ACCEPT


echo Special target for local addresses:
iptables --new LOCAL 2>/dev/null
echo $LOCAL_ADDRS
for ip in $LOCAL_ADDRS; do
iptables -A INPUT --dst $ip -j LOCAL
# iptables -A INPUT --src $ip -i ! lo -j LDROP # lame spoof protect
done
echo Authorize mail from mail relay.
iptables -A LOCAL --proto tcp --syn --src $MAIL_RELAY --dst $EXT_IP --dport 25 -j ACCEPT


echo Authorizing samba access to:
echo $SMB_ACCESS
iptables --new SMB 2>/dev/null
for ip in $SMB_ACCESS; do
iptables -A SMB -s $ip -j ACCEPT
done
iptables -A LOCAL --proto udp -i ! $EXT_IF --dport 135:139 -j SMB
iptables -A LOCAL --proto tcp -i ! $EXT_IF --dport 135:139 -j SMB
iptables -A LOCAL --proto tcp -i ! $EXT_IF --dport 445 -j SMB
iptables -A INPUT -i ! $EXT_IF --dst $SMB_BCAST -j ACCEPT #lame samba broadcast

echo Drop and log every other incoming tcp connection attempts.
iptables -A LOCAL -i ! lo --proto tcp --syn --j LDROP

echo Authorize dns access for local nets.
for net in $MASQ_NETS 127.0.0.0/8; do
iptables -A INPUT --proto udp --src $net --dport 53 -j ACCEPT
done


echo Enforcing up ICMP policies, use iptables -L ICMP to check.
# If you deny all ICMP messages you head for trouble since it would
# break lots of tcp/ip algorythm (acz)
iptables --new ICMP 2>/dev/null
iptables -A INPUT --proto icmp -j ICMP
iptables -A ICMP -p icmp --icmp-type echo-reply -j ACCEPT
iptables -A ICMP -p icmp --icmp-type destination-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type network-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type host-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type protocol-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type port-unreachable -j ACCEPT
iptables -A ICMP -p icmp --icmp-type fragmentation-needed -j LDROP
iptables -A ICMP -p icmp --icmp-type source-route-failed -j WATCH
iptables -A ICMP -p icmp --icmp-type network-unknown -j WATCH
iptables -A ICMP -p icmp --icmp-type host-unknown -j WATCH
iptables -A ICMP -p icmp --icmp-type network-prohibited -j WATCH
iptables -A ICMP -p icmp --icmp-type host-prohibited -j WATCH
iptables -A ICMP -p icmp --icmp-type TOS-network-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type TOS-host-unreachable -j WATCH
iptables -A ICMP -p icmp --icmp-type communication-prohibited -j WATCH
iptables -A ICMP -p icmp --icmp-type host-precedence-violation -j LDROP
iptables -A ICMP -p icmp --icmp-type precedence-cutoff -j LDROP
iptables -A ICMP -p icmp --icmp-type source-quench -j LDROP
iptables -A ICMP -p icmp --icmp-type redirect -j LDROP
iptables -A ICMP -p icmp --icmp-type network-redirect -j LDROP
iptables -A ICMP -p icmp --icmp-type host-redirect -j LDROP
iptables -A ICMP -p icmp --icmp-type TOS-network-redirect -j LDROP
iptables -A ICMP -p icmp --icmp-type TOS-host-redirect -j LDROP
iptables -A ICMP -p icmp --icmp-type echo-request -j WATCH
iptables -A ICMP -p icmp --icmp-type router-advertisement -j LDROP
iptables -A ICMP -p icmp --icmp-type router-solicitation -j LDROP
iptables -A ICMP -p icmp --icmp-type time-exceeded -j WATCH
iptables -A ICMP -p icmp --icmp-type ttl-zero-during-transit -j WATCH
iptables -A ICMP -p icmp --icmp-type ttl-zero-during-reassembly -j WATCH
iptables -A ICMP -p icmp --icmp-type parameter-problem -j WATCH
iptables -A ICMP -p icmp --icmp-type ip-header-bad -j WATCH
iptables -A ICMP -p icmp --icmp-type required-option-missing -j WATCH
iptables -A ICMP -p icmp --icmp-type timestamp-request -j LDROP
iptables -A ICMP -p icmp --icmp-type timestamp-reply -j LDROP
iptables -A ICMP -p icmp --icmp-type address-mask-request -j LDROP
iptables -A ICMP -p icmp --icmp-type address-mask-reply -j LDROP
iptables -A ICMP -p icmp -j LDROP

echo Authorize tcp traffic.
iptables -A INPUT --proto tcp -j ACCEPT

echo Authorize packet output.
iptables --policy OUTPUT ACCEPT

#echo reject ident if you drop em you gotta wait for timeout
#iptables -I LOCAL --proto tcp --syn --dst $EXT_IP --dport 113 -j REJECT

echo Drop and log all udp below 1024.
iptables -A INPUT -i ! lo --proto udp --dport :1023 -j LDROP

echo Drop rpc dynamic udp port:
RPC_UDP=`rpcinfo -p localhost|perl -n -e /.*udps+(d+)s+/ && print $1,"n"|sort -u`
echo $RPC_UDP
for port in $RPC_UDP; do
iptables -A LOCAL -i ! lo --proto udp --dport $port -j LDROP
done

echo Authorize udp above 1024.
iptables -A INPUT --proto udp --dport 1024: -j ACCEPT

Aps is a small tool for analyzing network traffic. It prints out a great deal of information about the relevant protocols including TCP, UDP, ARP, and ICMP.
It allows you to filter IP addresses, hardware addresses, ports, and specific protocols. It comes with a little GTK-GUI displaying packet counters for each protocol.
APS tries to print detailed info about network frames that are received from the SOCK_RAW (ETH_P_ALL) socket. I am not sure if this is the clean way, but it works fine. APS prints info about the hardware layer and the IP and TCP/UDP/ICMP header.
The tail of the packet (mostly the data) wich could not be interpreted is written on the screen as ascii/hex-dump or both (your choice).
Example
HW-ADDR: 00:60:8c:f6:40:96 -----> 00:80:ad:30:8f:3b
IP-ADDR: 192.168.17.52 -----> 192.168.17.50
IP-Ver4 || Head:0x0a (bytes) || Service(TOS):16 || Length over all:0061
Fragmentation: ID:0x4079 - Flags: 0 1 0 - Offset:00000
TTL:064 || Protokoll:006 (TCP) || HeaderCRC:0x567b
TCP-HEADER:
Ports: 0023-->1034 (telnet) Seq./Ack. Nr.:0x70843468 / 0xeae29434
Data-Offset:0x05 Reserved-6Bit:00 Flags:-urg-ACK-PSH-rst-syn-fin-
Window:0x7fe0 CRC:0x9420 Urgent-Pointer:0x0000
73 61 74 75 72 6e 32 3a 2f 73 72 76 2f 70 72 69 6e 74 71 23 20
HW-ADDR: 52:54:40:25:8d:88 -----> ff:ff:ff:ff:ff:ff
SAMBA/NetBios
e0 e0 03 ff ff 00 22 00 11 00 00 00 00 ff ff ff ff ff ff 04 52 00 00 00 00 52
40 25 8d 88 40 08 00 03 00 04 20 20 20 20 20 20 20 20 20
HW-ADDR: 00:80:ad:30:8f:3b -----> 00:60:8c:f6:40:96
IP-ADDR: 192.168.17.50 -----> 194.112.123.200
IP-Ver4 || Head:0x0a (bytes) || Service(TOS):0 || Length over all:0029
Fragmentation: ID:0x29ae - Flags: 0 0 0 - Offset:00000
TTL:064 || Protokoll:001 (ICMP) || HeaderCRC:0x411f
echo request CODE:0x0 CRC:0xf9f5 SIG:0x602 NUM:0x0
00 ea
Enhancements:
- added break for Packet-counter and fixed some minor bugs

deja-packet transmits raw packets through a specified interface.

Usage: ./deja-packet -pcap < libpcap capture file > < interface name >
or: ./deja-packet -raw < raw packet file > < interface name >

Note: you must be root to successfully transmit packets with deja-packet due to the Linux security restrictions with raw sockets.

In the [-p]cap mode, deja-packet transmits selected packets from a libpcap capture file (such as one created by Ethereal/Wireshark, or tcpdump). In the [-r]aw mode, deja-packet transmits the raw contents of a file as one whole packet.

The [-p]cap mode is interactive: the user will be continuously prompted to select which packet from the libpcap capture file to transmit, until the “q” character is encountered, where the program will quit.

Example pcap mode:

$ sudo ./deja-packet -p icmp_ping.pcap eth0
Select packet number (1 to 6) for transmission or q for quit: 1
Successfully transmitted packet!
Select packet number (1 to 6) for transmission or q for quit: 2
Successfully transmitted packet!
Select packet number (1 to 6) for transmission or q for quit: 5
Successfully transmitted packet!
Select packet number (1 to 6) for transmission or q for quit: 6
Successfully transmitted packet!
Select packet number (1 to 6) for transmission or q for quit: q
$

In the [-r]aw mode, deja-packet exits immediately after the attempted transmission is complete (allows deja-packet to be easily used with a script).

Example raw mode:

$ sudo ./deja-packet -r samplepacket eth0
Successfully transmitted packet!
$

icmp_ping.pcap is included as a sample libpcap capture file.

To compile deja-packet, simply use the command “make”.

deja-packet remains Linux-only because it requires PF_PACKET sockets.

This project is released under the GNU General Public License version 2.

Layer-7 Packet Classifier for Linux is a packet classifier for Netfilter that identifies packets based on application layer (OSI layer 7) data. This means that it is able to classify packets as HTTP, FTP, Gnucleus, Kazaa, etc., regardless of ports.
It complements existing matches that classify based on port numbers, packet length, TOS bits, and so on. Combined with Linux QoS, it allows for full layer 7 packet shaping.
Main features:
- Patches for Linux 2.4 and 2.6
- Support for TCP, UDP and ICMP over IPv4
- Uses Netfilters connection tracking of FTP, IRC, etc
- Examines data across multiple packets
- Number of packets examined tunable on the fly through /proc
- Number of bytes examined tunable at module load time
- Distinguishes between new connections (those still being tested) and old unidentified connections
- Gives access to both Netfilter and QoS (rate limiting) features
- With the Netfilter "helper" match, you can distinguish between parent and child connections (e.g. ftp command/data)

RADIUS::Packet is an object-oriented Perl interface to RADIUS packets.

SYNOPSIS

use RADIUS::Packet;
use RADIUS::Dictionary;

my $d = new RADIUS::Dictionary "/etc/radius/dictionary";

my $p = new RADIUS::Packet $d, $data;
$p->dump;

if ($p->attr(User-Name eq "lwall") {
my $resp = new RADIUS::Packet $d;
$resp->set_code(Access-Accept);
$resp->set_identifier($p->identifier);
$resp->set_authenticator($p->authenticator);
$resp->set_attr(Reply-Message) = "Welcome, Larry!rn";
my $respdat = auth_resp($resp->pack, "mysecret");
...

RADIUS (RFC2138) specifies a binary packet format which contains various values and attributes. RADIUS::Packet provides an interface to turn RADIUS packets into Perl data structures and vice-versa.

RADIUS::Packet does not provide functions for obtaining RADIUS packets from the network. A simple network RADIUS server is provided as an example at the end of this document. Also, a RADIUS::Server module is under development which will simplify the interface.

SYNOPSIS

use NetPacket::IP;

$ip_obj = NetPacket::IP->decode($raw_pkt);
$ip_pkt = NetPacket::IP->encode($ip_obj);
$ip_data = NetPacket::IP::strip($raw_pkt);

NetPacket::IP provides a set of routines for assembling and disassembling packets using IP (Internet Protocol).

Methods

NetPacket::IP->decode([RAW PACKET])

Decode the raw packet data given and return an object containing instance data. This method will quite happily decode garbage input. It is the responsibility of the programmer to ensure valid packet data is passed to this method.

NetPacket::IP->encode()

Return an IP packet encoded with the instance data specified. This will infer the total length of the packet automatically from the payload lenth and also adjust the checksum.

Functions

NetPacket::IP::strip([RAW PACKET])

Return the encapsulated data (or payload) contained in the IP packet. This data is suitable to be used as input for other NetPacket::* modules.

This function is equivalent to creating an object using the decode() constructor and returning the data field of that object.

Instance data

The instance data for the NetPacket::IP object consists of the following fields.

ver

The IP version number of this packet.

hlen

The IP header length of this packet.

flags

The IP header flags for this packet.

foffset

The IP fragment offset for this packet.

tos

The type-of-service for this IP packet.

len

The length (including length of header) in bytes for this packet.

id

The identification (sequence) number for this IP packet.

ttl

The time-to-live value for this packet.

proto

The IP protocol number for this packet.

cksum

The IP checksum value for this packet.

src_ip

The source IP address for this packet in dotted-quad notation.

dest_ip

The destination IP address for this packet in dotted-quad notation.

options

Any IP options for this packet.

data

The encapsulated data (payload) for this IP packet.