HPING2(8) HPING2(8)

NAME
hping2 - send (almost) arbitrary TCP/IP packets to network hosts

SYNOPSIS
hping2 [ -hvnqVDzZ012WrfxykQbFSRPAUXYjJBuTG ] [ -c count ] [ -i wait ] [ --fast ] [
-I interface ] [ -9 signature ] [ -a host ] [ -t ttl ] [ -N ip id ] [ -H ip proto
col ] [ -g fragoff ] [ -m mtu ] [ -o tos ] [ -C icmp type ] [ -K icmp code ] [ -s
source port ] [ -p[+][+] dest port ] [ -w tcp window ] [ -O tcp offset ] [ -M tcp
sequence number ] [ -L tcp ack ] [ -d data size ] [ -E filename ] [ -e signature ]
[ --icmp-ipver version ] [ --icmp-iphlen length ] [ --icmp-iplen length ] [
--icmp-ipid id ] [ --icmp-ipproto protocol ] [ --icmp-cksum checksum ] [ --icmp-ts
] [ --icmp-addr ] [ --tcpexitcode ] [ --tcp-timestamp ] [ --tr-stop ] [ --tr-keep-
ttl ] [ --tr-no-rtt ] [ --rand-dest ] [ --rand-source ] hostname

DESCRIPTION
hping2 is a network tool able to send custom TCP/IP packets and to display target
replies like ping program does with ICMP replies. hping2 handle fragmentation,
arbitrary packets body and size and can be used in order to transfer files encapsu
lated under supported protocols. Using hping2 you are able to perform at least the
following stuff:

- Test firewall rules
- Advanced port scanning
- Test net performance using different protocols,
packet size, TOS (type of service) and fragmentation.
- Path MTU discovery
- Transferring files between even really fascist firewall
rules.
- Traceroute-like under different protocols.
- Firewalk-like usage.
- Remote OS fingerprinting.
- TCP/IP stack auditing.
- A lot of others.

It's also a good didactic tool to learn TCP/IP. hping2 is developed and maintained
by antirez@invece.org and is licensed under GPL version 2. Development is open so
you can send me patches, suggestion and affronts without inhibitions.

HPING SITE
primary site at http://www.hping.org You can found both the stable release and the
instruction to download the latest source code at http://www.hping.org/down
load.html

BASE OPTIONS
-h --help
Show an help screen on standard output, so you can pipe to less.

-v --version
Show version information and API used to access to data link layer, linux
sock packet or libpcap

-c --count count
Stop after sending (and receiving) count response packets. After last packet
was send hping2 wait COUNTREACHED_TIMEOUT seconds target host replies. You
are able to tune COUNTREACHED_TIMEOUT editing hping2.h

-i --interval
Wait the specified number of seconds or micro seconds between sending each
packet. --interval X set wait to X seconds, --interval uX set wait to X
micro seconds. The default is to wait one second between each packet. Using
hping2 to transfer files tune this option is really important in order to
increase transfer rate. Even using hping2 to perform idle/spoofing scanning
you should tune this option, see HPING2-HOWTO for more information.

--fast Alias for -i u10000. Hping will send 10 packets for second.

-n --numeric
Numeric output only, No attempt will be made to lookup symbolic names for
host addresses.

-q --quiet
Quiet output. Nothing is displayed except the summary lines at startup time
and when finished.

-I --interface interface name
By default on linux and BSD systems hping2 uses default routing interface.
In other systems or when there is no default route hping2 uses the first
non-loopback interface. However you are able to force hping2 to use the
interface you need using this option. Note: you don't need to specify the
whole name, for example -I et will match eth0 ethernet0 myet1 et cetera. If
no interfaces match hping2 will try to use lo.

-V --verbose
Enable verbose output. TCP replies will be shown as follows:

len=46 ip=192.168.1.1 flags=RA DF seq=0 ttl=255 id=0 win=0 rtt=0.4 ms tos=0
iplen=40 seq=0 ack=1380893504 sum=2010 urp=0

-D --debug
Enable debug mode, it's useful when you experience some problem with hping2.
When debug mode is enabled you will get more information about interface
detection, data link layer access, interface settings, options parsing,
fragmentation, HCMP protocol and other stuff.

-z --bind
bind CTRL+Z to time to live (TTL) so you will able to increment/decrement
ttl of outgoing packets pressing CTRL+Z once or twice.

-Z --unbind
unbind CTRL+Z so you will able to stop hping2

PROTOCOL SELECTION
Default protocol is TCP, by default hping2 will send tcp headers to target host's
port 0 with a winsize of 64 without any tcp flag on. Often this is the best way to
do an 'hide ping', useful when target is behind a firewall that drop ICMP. Moreover
a tcp null-flag to port 0 has a good probability of not being logged.

-0 --rawip
RAW IP mode, in this mode hping2 will send IP header with data appended with
--signature and/or --file, see also --ipproto that allows you to set the ip
protocol field.

-1 --icmp
ICMP mode, by default hping2 will send ICMP echo-request, you can set other
ICMP type/code using --icmptype --icmpcode options.

-2 --udp
UDP mode, by default hping2 will send udp to target host's port 0. UDP
header tunable options are the following: --baseport, --destport, --keep.

-9 --listen signature
HPING2 listen mode, using this option hping2 waits for packet that contain
signature and dump from signature end to packet's end. For example if hping2
--listen TEST reads a packet that contain 234-09sdflkjs45-TESThello_world it
will display hello_world.

IP RELATED OPTIONS
-a --spoof hostname
Use this option in order to set a fake IP source address, this option
ensures that target will not gain your real address. However replies will be
sent to spoofed address, so you will can't see them. In order to see how
it's possible to perform spoofed/idle scanning see the HPING2-HOWTO.

--rand-source
This option enables the random source mode. hping will send packets with
random source address. It is interesting to use this option to stress fire
wall state tables, and other per-ip basis dynamic tables inside the TCP/IP
stacks and firewall software.

--rand-dest
This option enables the random destination mode. hping will send the pack
ets to random addresses obtained following the rule you specify as the tar
get host. You need to specify a numerical IP address as target host like
10.0.0.x. All the occurrences of x will be replaced with a random number in
the range 0-255. So to obtain internet IP addresses in the whole IPv4 space
use something like hping x.x.x.x --rand-dest. If you are not sure about
what kind of addresses your rule is generating try to use the --debug switch
to display every new destination address generated. When this option is
turned on, matching packets will be accept from all the destinations. Warn
ing: when this option is enabled hping can't detect the right outgoing
interface for the packets, so you should use the --interface option to
select the desidered outgoing interface.

-t --ttl time to live
Using this option you can set TTL (time to live) of outgoing packets, it's
likely that you will use this with --traceroute or --bind options. If in
doubt try ` hping2 some.host.com -t 1 --traceroute

-N --id
Set ip->id field. Default id is random but if fragmentation is turned on and
id isn't specified it will be getpid() & 0xFF , to implement a better solu
tion is in TODO list.

-H --ipproto
Set the ip protocol in RAW IP mode.

-W --winid
Windows* id has different byte ordering, if this option is enable hping2
will properly display windows reply ids.

-r --rel
Display id increments instead of id. See the HPING2-HOWTO for more informa
tion. Increments aren't computed as id[N]-id[N-1] but using packet loss com
pensation. See relid.c for more information.

-f --frag
Split packets in more fragments, this may be useful in order to test IP
stacks fragmentation performance and to test if some packet filter is so
weak that can be passed using tiny fragments (anachronistic). Default 'vir
tual mtu' is 16 bytes. see also --mtu option.

-x --morefrag
Set more fragments IP flag, use this option if you want that target host
send an ICMP time-exceeded during reassembly.

-y --dontfrag
Set don't fragment IP flag, this can be used to perform MTU path discovery.

-g --fragoff fragment offset value
Set the fragment offset

-m --mtu mtu value
Set different 'virtual mtu' than 16 when fragmentation is enabled. If pack
ets size is greater that 'virtual mtu' fragmentation is automatically turned
on.

-o --tos hex_tos
Set Type Of Service (TOS) , for more information try --tos help

-G --rroute
Record route. Includes the RECORD_ROUTE option in each packet sent and dis
plays the route buffer of returned packets. Note that the IP header is only
large enough for nine such routes. Many hosts ignore or discard this option.
Also note that using hping you are able to use record route even if target
host filter ICMP. Record route is an IP option, not an ICMP option, so you
can use record route option even in TCP and UDP mode.

ICMP RELATED OPTIONS
-C --icmptype type
Set icmp type, default is ICMP echo request (implies --icmp)

-K --icmpcode code
Set icmp code, default is 0. (implies --icmp)

--icmp-ipver
Set IP version of IP header contained into ICMP data, default is 4.

--icmp-iphlen
Set IP header length of IP header contained into ICMP data, default is 5 (5
word of 32 bits).

--icmp-iplen
Set IP packet length of IP header contained into ICMP data, default is the
real length.

--icmp-ipid
Set IP id of IP header contained into ICMP data, default is random.

--icmp-ipproto
Set IP protocol of IP header contained into ICMP data, default is TCP.

--icmp-cksum
Set ICMP checksum, for default is the valid checksum.

--icmp-ts
Alias for --icmptype 13 (to send ICMP timestamp requests)

--icmp-addr
Alias for --icmptype 17 (to send ICMP address mask requests)

TCP/UDP RELATED OPTIONS
-s --baseport source port
hping2 uses source port in order to guess replies sequence number. It starts
with a base source port number, and increase this number for each packet
sent. When packet is received sequence number can be computed as
replies.dest.port - base.source.port. Default base source port is random,
using this option you are able to set different number. If you need that
source port not be increased for each sent packet use the -k --keep option.

-p --destport [+][+]dest port
Set destination port, default is 0. If '+' character precedes dest port num
ber (i.e. +1024) destination port will be increased for each reply received.
If double '+' precedes dest port number (i.e. ++1024), destination port will
be increased for each packet sent. By default destination port can be modi
fied interactively using CTRL+z.

--keep keep still source port, see --baseport for more information.

-w --win
Set TCP window size. Default is 64.

-O --tcpoff
Set fake tcp data offset. Normal data offset is tcphdrlen / 4.

-M --tcpseq
Set the TCP sequence number.

-L --tcpack
Set the TCP ack.

-Q --seqnum
This option can be used in order to collect sequence numbers generated by
target host. This can be useful when you need to analyze whether TCP
sequence number is predictable. Output example:

#hping2 win98 --seqnum -p 139 -S -i u1 -I eth0
HPING uaz (eth0 192.168.4.41): S set, 40 headers + 0 data bytes
2361294848 +2361294848
2411626496 +50331648
2545844224 +134217728
2713616384 +167772160
2881388544 +167772160
3049160704 +167772160
3216932864 +167772160
3384705024 +167772160
3552477184 +167772160
3720249344 +167772160
3888021504 +167772160
4055793664 +167772160
4223565824 +167772160

The first column reports the sequence number, the second difference between
current and last sequence number. As you can see target host's sequence num
bers are predictable.

-b --badcksum
send packets with a bad UDP/TCP checksum

--tcp-timestamp
enable the TCP timestamp option, and try to guess the timestamp update fre
quency and the remote system uptime.

-F --fin
set FIN tcp flag.

-S --syn
set SYN tcp flag.

-R --rst
set RST tcp flag.

-P --push
set PUSH tcp flag.

-A --ack
set ACK tcp flag.

-U --urg
set URG tcp flag.

-X --xmas
set Xmas tcp flag.

-Y --ymas
set Ymas tcp flag.

COMMON OPTIONS
-d --data data size
set packet body size. Warning, using --data 40 hping2 will not generate 0
byte packets but protocol_header+40 bytes. hping2 will display packet size
information as first line output, like this: HPING www.yahoo.com (ppp0
204.71.200.67): NO FLAGS are set, 40 headers + 40 data bytes

-E --file filename
Use filename contents to fill packet's data.

-e --sign signature
Fill first signature length bytes of data with signature. If the signature
length is bigger than data size an error message will be displayed. If you
don't specify the data size hping will use the signature size as data size.
This option can be used safely with --file filename option, remainder data
space will be filled using filename

-j --dump
Dump received packets in hex.

-J --print
Dump received packets's printable characters.

-B --safe
Enable safe protocol, using this option lost packets in file transfers will
be resent. For example in order to send file /etc/passwd from host A to host
B you may use the following:
[host_a]
# hping2 host_b --udp -p 53 -d 100 --sign signature --safe --file /etc/passwd
[host_b]
# hping2 host_a --listen signature --safe --icmp

-u --end
If you are using --file filename option, tell you when EOF has been reached.
Moreover prevent that other end accept more packets. Please, for more infor
mation see the HPING2-HOWTO.

-T --traceroute
Traceroute mode. Using this option hping2 will increase ttl for each ICMP
time to live 0 during transit received. Try hping2 host --traceroute. This
option implies --bind and --ttl 1. You can override the ttl of 1 using the
--ttl option. Since 2.0.0 stable it prints RTT information.

--tr-keep-ttl
Keep the TTL fixed in traceroute mode, so you can monitor just one hop in
the route. For example, to monitor how the 5th hop changes or how its RTT
changes you can try hping2 host --traceroute --ttl 5 --tr-keep-ttl.

--tr-stop
If this option is specified hping will exit once the first packet that isn't
an ICMP time exceeded is received. This better emulates the traceroute
behavior.

--tr-no-rtt
Don't show RTT information in traceroute mode. The ICMP time exceeded RTT
information aren't even calculated if this option is set.

--tcpexitcode
Exit with last received packet tcp->th_flag as exit code. Useful for scripts
that need, for example, to known if the port 999 of some host reply with
SYN/ACK or with RST in response to SYN, i.e. the service is up or down.

TCP OUTPUT FORMAT
The standard TCP output format is the following:

len=46 ip=192.168.1.1 flags=RA DF seq=0 ttl=255 id=0 win=0 rtt=0.4 ms

len is the size, in bytes, of the data captured from the data link layer excluding
the data link header size. This may not match the IP datagram size due to low level
transport layer padding.

ip is the source ip address.

flags are the TCP flags, R for RESET, S for SYN, A for ACK, F for FIN, P for PUSH,
U for URGENT, X for not standard 0x40, Y for not standard 0x80.

If the reply contains DF the IP header has the don't fragment bit set.

seq is the sequence number of the packet, obtained using the source port for
TCP/UDP packets, the sequence field for ICMP packets.

id is the IP ID field.

win is the TCP window size.

rtt is the round trip time in milliseconds.

If you run hping using the -V command line switch it will display additional infor
mation about the packet, example:

len=46 ip=192.168.1.1 flags=RA DF seq=0 ttl=255 id=0 win=0 rtt=0.4 ms tos=0
iplen=40 seq=0 ack=1223672061 sum=e61d urp=0

tos is the type of service field of the IP header.

iplen is the IP total len field

seq and ack are the sequence and acknowledge 32bit numbers in the TCP header.

sum is the TCP header checksum value

urp is the TCP urgent pointer value

UDP OUTPUT FORMAT
The standard output format is:

len=46 ip=192.168.1.1 seq=0 ttl=64 id=0 rtt=6.0 ms

The field meaning is just the same as the TCP output meaning of the same fields.

ICMP OUTPUT FORMAT
An example of ICMP output is:

ICMP Port Unreachable from ip=192.168.1.1 name=nano.marmoc.net

It is very simple to understand. It starts with the string "ICMP" followed by the
description of the ICMP error, Port Unreachable in the example. The ip field is the
IP source address of the IP datagram containing the ICMP error, the name field is
just the numerical address resolved to a name (a dns PTR request) or UNKNOWN if the
resolution failed.

The ICMP Time exceeded during transit or reassembly format is a bit different:

TTL 0 during transit from ip=192.168.1.1 name=nano.marmoc.net

TTL 0 during reassembly from ip=192.70.106.25 name=UNKNOWN

The only difference is the description of the error, it starts with TTL 0.

AUTHOR
Salvatore Sanfilippo <antirez@invece.org>, with the help of the people mentioned in
AUTHORS file and at http://www.hping.org/authors.html

BUGS
Even using the --end and --safe options to transfer files the final packet will be
padded with 0x00 bytes.

Data is read without care about alignment, but alignment is enforced in the data
structures. This will not be a problem under i386 but, while usually the TCP/IP
headers are naturally aligned, may create problems with different processors and
bogus packets if there is some unaligned access around the code (hopefully none).

On solaris hping does not work on the loopback interface. This seems a solaris
problem, as stated in the tcpdump-workers mailing list, so the libpcap can't do
nothing to handle it properly.

SEE ALSO
ping(8), traceroute(8), ifconfig(8), nmap(1)

2001 Aug 14 HPING2(8)