SING(8)

NAME
sing - Send ICMP Nasty Garbage packets to network hosts

SYNOPSIS
sing [-hVRnvqGQOBU] [-c count] [-T wait] [-p pattern] [-s datasize] [-F bytes] [-i interface] [-S spoof] [-t ttl] [-TOS tos] [-l preload] [-M os] [-L logfile] [-MAC hw_addr] [-x code] [type] host

DESCRIPTION
sing is a tool that sends ICMP packets fully customized from command line. The main purpose is to replace the niceful ping command with certain enhancenments as the ability to send/read IP spoofed packets, send MAC spoofed packets, send in addition to the ECHO REQUEST type sent by default, many other ICMP types as Echo Reply, Address Mask Request, Timestamp, Information Request,Router Solicitation and Router Advertisement. It supports also the following ICMP error types: Redirect, Source Quench, Time Exceeded, Destination Unreachable and Parameter Problem. It can do a little fingerprinting, see the FINGERPRINTING TECHNIQUES section to read more details about. It can emulate certain OOSS sending Echo Request or Echo Reply packets. See the MIMIC TECHNIQUES section for a more accurate information. The host destination can also be specified as a list of gateways (including destination) breaked by the '%' symbol meaning the use of a Strict Source Routing IP Option (v.g. router1%router2%router3%host) or the '@' symbol meaning the use of a Loose Source Routing IP Option (v.g. router1@router2@router3@host). A long number of examples is given at the EXAMPLES section of this page that shows a real use of this program.

MOST COMMON OPTIONS

-h, --help
    Help screen.

-V, --Version
    Program version.

-v  Verbose mode.

-B  Send a Bad ICMP Checksum on Information types.

-c count
    Stop after sending (and receiving) count packets. Information types only.

-F bytes
    Fragment the entire ICMP packet with bytes size by fragment. Not used on Solaris systems.

-G  Set the IP header Don't Fragment flag. Not used on Solaris systems.

-i interface
    Interface (name or IP address) where listen on for replies.

-l preload
    If preload is specified, sing sends that many packets as fast as possible before falling into its normal mode of behavior. Only the super-user may use this option. Information types only.

-L logfile
    Save the current session to the file logfile. If logfile exists the data will be appended at end.

-M os
    Do mimic of the os specified when sending an Echo Request or Echo Reply. os can be win, unix, linux, cisco, solaris or shiva.

-MAC hw_address
    Do MAC spoofing using the MAC hw_address (maybe to surpass filtered switches). Be aware of using on an interface with a datalink type different of Ethernet. The MAC address must be on hexadecimal form and must be delimited by ':' (Example: 00:FF:AC:33:1:B). This option made use of the libnet library to acces the network link layer. Only the super-user can use this option.

-n  Don't use name resolution.

-O  Do fingerprinting to discover the target OS.

-p pattern
    You may specify a pattern of bytes to fill out the packet you send. This is useful for diagnosing data-dependent problems in a network. For example, `-p INPACK'' will cause the sent packet to be filled with the word INPACK.

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

-Q  Totally quiet output. Absolutly nothing is displayed. Useful to use within shell scripts.

-R  Use Record Route IP Header Option on the ICMP packet.

-s bytes|max
    Number of garbage bytes that will be sent on any ICMP packet. With max the maximum possible will be sent.

-S address
    IP address to be used as the source of the ICMP packet. This force the use of the libpcap routines that puts your network interface into promiscuous mode to be able to read the replies. Only the super-user may use this option.

-t ttl
    Set the IP Time To Live field to ttl value.

-T wait
    Wait wait seconds between sending each packet. The default is to wait for one second between each packet.

-TOS tos
    Set the IP Type Of Service field to tos value.

-U  Set the IP header Unused bit flag. Be aware on *BSD systems because the kernel set to 0 the IP header flags when using the Reserved Bit so SING must revert to promiscuous mode to be able to read the response with libpcap. Not used on Solaris systems.

-x, --xcode code|num|max
    ICMP code to send. Code code valid for Destination Unreachable (-du), Redirect (-red) and Time Exceeded (-tx) types. Numerical code can be specified for the ICMP types that doesn't have (Echo Request, Information Request, Address Mask Request, Router Solicitation, Router Advertisement, Source Quench, Parameter Problem and Timestamp). Using max an ICMP code greater than the admited ones will be sent. See the ICMP CODES section for a long list of code types.

ICMP TYPES
The type can be any of the following below:

-echo, --echo_request
    Echo Request. Request sent to a host to receive an echo reply. This is the type sent by default. This ICMP type is information.

-tstamp, --timestamp
    Timestamp. Host request to receive the time of another host. This ICMP type is information.

-mask, --mask_req
    Address Mask Request. Used to find out a host network mask. This ICMP type is information.

-info, --info_req
    Information Request. Host request to receive an Info Reply from another host. This ICMP type is information.

-du, --dest_unreach
    Destination Unreach. IP packet couldn't be given. This ICMP type is error.

-sq, --src_quench
    Source Quench. IP packet is not given due a net congestion. This ICMP type is error.

-red, --redirect
    Redirect. Request to forward IP packets through another router. This ICMP type is error.

-rta, --router_advert address[/preference]
    Router Advertisement. Router trasmits one or more routers with address address and preference preference. If this is ommited, default preference 0 is given. This ICMP type is information.

-rts, --router_solicit
    Router Solicitation. Host requeriment for a message of one or more routers. Like the previous, is a part of the messages exchange Router Discovery and this ICMP type is information.

-tx, --time_exc
    Time Exceeded. Time Exceeded for an IP packet. This ICMP type is error.

-param, --param_problem
    Parameter Problem. Erroneous value on a variable of IP header. This ICMP type is error.

-reply
    Echo Reply. Response to a Echo Request. This ICMP type is information.

LESS COMMON OPTIONS
The options can be any of the following:

-lt, --lifetime secs
    Lifetime in seconds of the router announcement. Only valid with Router Advertisement (-rta) type. 1800 seconds by default (30').

-gw, --gateway address
    Route gateway address on an ICMP Redirect (-red). By default will be the spoof address (-S), if it has been specified, or the outgoing IP address if it has not been specified.

-dest, --route_dest address
    Route destination address on an ICMP Redirect (-red). This is a required option when sending an ICMP Redirect.

-orig, --orig_host address
    Original host within the IP header sent in the 64 bits data field of an ICMP error. By default will be the same as the IP of the host that sends the ICMP packet.

-psrc, --port_src port
    Source port (tcp or udp) within the IP header sent in the 64 bits data field of an ICMP error. 0 by default.

-pdst, --port_dst port
    Destination port (tcp or udp) within the IP header sent in the 64 bits data field of an ICMP error. 0 by default.

-prot, --protocol name|number
    Protocol to be used within the IP header sent in the 64 bits data field of an ICMP error. Must be a name from the /etc/protocols or a protocol number. Only tcp, udp and icmp are fully implemented, with other protocols the remaining of the 64 bits field are fulfilled with 0xFF. TCP by default.

-id  identificator
    ICMP id to be used with ICMP of Information types. Do not be confused with the -ip_id option!.

-seq sequence
    Echo sequence number to be used with Echo Request or Echo Reply types. Do not be confused with the -ip_seq option!.

-ip_id  identificator
    Echo identificator within the IP header sent in the 64 bits data field of an ICMP error when the IP header protocol of the 64 bits data field (-prot) is icmp. 0 by default.

-ip_seq  sequence
    Echo sequence number within the IP header sent in the 64 bits data field of an ICMP error when the IP header protocol of the 64 bits data field (-prot) is icmp. 0 by default.

-ptr, --pointer byte
    Pointer to erroneus byte byte on an ICMP packet showing a parameter problem. Valid only on Parameter Problem type (-param).

ICMP CODES
Valid codes used with Destination Unreach, Redirect and Time Exceeded types are,

- Used with Destination Unreach type (-du):

net-unreach (Net Unreachable) The destination net is unreachable. host-unreach (Host Unreachable) The destination host is unreachable. prot-unreach (Protocol Unreachable) desired protocol is unreachable to destination host. port-unreach (Port Unreachable) desired port is unreachable to destination host. frag-needed (Fragmentation Needed and Don't Fragment was Set) Shows that IP packet had to be fragmented because of its size but the sender did not allowed it because the DF (DON'T FRAGMENT) flag was set. sroute-fail (Source Route Failed) could'nt follow the route indicated on IP packet. net-unknown (Destination Network Unknown) Destination network is unknown. host-unknown (Destination Host Unknown) Destination host unknown but network is. host-isolated (Source Host Isolated) Can't reach destination host. net-ano (Communication with Destination Network is Administratively Prohibited) access network is denied through firewall or similar on receiver side. host-ano (Communication with Destination Host is Administratively Prohibited) access host is denied through firewall or similar on receiver side. net-unr-tos (Destination Network Unreachable for Type of Service) indicates on destination network that the Type Of Service (TOS) applied for is not allowed. host-unr-tos (Destination Host Unreachable for Type of Service) shows that destination host is unreachable with applied TOS. com-admin-prohib (Communication Administratively Prohibited) a router can't forward a packet because of administrative filter. host-precedence-viol (Host Precedence Violation) IP packet precedence is not allowed. precedence-cutoff (Precedence cutoff in effect) a smaller IP packet precedence has tried to be sent over the minimal impossed by network manager.

- To be used with Redirect type (-red):

net (Redirect Datagram for the Network) shows that destination is a network. host (Redirect Datagram for the Host) shows that destination is a host. serv-net (Redirect Datagram for the Type Of Service and Network) destination is a type of service and network. serv-host (Redirect Datagram for the Type Of Service and Host) destination is a type of service and host.

and

- to be used with Time Exceeded type (-tx):

ttl (Time to Live exceeded in Transit) time is over on an IP packet header packet. frag (Fragment Reassembly Time Exceeded) could not reassembly all the IP packet fragments.

FINGERPRINTING TECHNIQUES
With the -O option SING can use little techniques of remote OS fingerprinting. To distinguish between Window$ boxes and the rest of the world Ofir Arkin has discovered a simple method: Sending an ICMP code that is not 0 within an ICMP Echo Request, a Window$ box respond with a 0 code while the rest of the boxes would leave the code field unchanged. See the SEE ALSO section. With Solaris systems SING use a method discovered by me: Sending a fragmented Addres Mask Request any Solaris system (tested from 2.5.1 to Solaris8 Intel & SPARC) respond with an Address Mask of 0's. Last update!: Some people have noticed that HP-UX v11.0 respond the same way. See the EXAMPLES section for examples.

MIMIC TECHNIQUES
With the -M option SING can try to emulate certain OS. At the moment Window$98/Window$NT4 (win value), UNIX (unix value), Linux (linux value), Cisco (cisco value), Solaris (solaris value) or Shiva (shiva value) are the only accepted values. To emulate them SING changes its normal behaviour about the IP header flags, the TTL, the initial ICMP sequence number, the ICMP id and the ICMP data that each OS send. These techniques are aplied only when using Echo Request or Echo Reply types.

RETURN VALUES
sing can be easily used within shell scripts. Program returns the following values to the shell:
Value Meaning
----- -----------
0 Received at least 1 response from destination host.
1 General Error.
2 Packet sent OK but received no response.
3 Out of memory.

EXAMPLES
- Testing if www.solarisbox.xx is running the Solaris OS. Supposed no filter methods: sing -mask -O www.solarisbox.xx - Testing if www.winbox.xx is running the Window$ OS: sing -O www.winbox.xx - Send Echos with garbage size of 32 bytes and fragments of 8 bytes to host www.provatina.xx: sing -s 32 -F 8 www.provatina.xx - Send Echos with data pattern IsSiNg and fragments of 8 bytes to the host www.provatina.xx using Loose Source Routing via router1.xx and router2.xx: sing -p IsSiNg -F 8 router1.xx@router2.xx@www.provatina.xx - Send an ICMP packet Timestamp to host sepultura.hell. We spoof as host 10.2.3.1: sing -tstamp -S 10.2.3.1 sepultura.hell - Send an ICMP packet Router Solicitation to 10.13.1.0: sing -rts 10.13.1.0 - Send an ICMP Router Advertisement to host death.es, saying that the routers to use are: router1.xtc with preference 20, router2.xtc with preference 50 and router3.xtc with default preference (0). We spoof as fatherouter.xtc: sing -rta router1.xtc/20 -rta router2.xtc/50 -rta router3.xtc -S fatherouter.xtc death.es - In response to a packet send with TCP source port 100 and destination on port 90, we want to send and ICMP Redirect to dwdwah.xx to modify its routing table with the following data: 10.12.12.12 as a gateway to the host death.es masking the packet source as if it was sent from infect.comx host:

sing -red -S infect.comx -gw 10.12.12.12 -dest death.es -x host -prot tcp -psrc 100 -pdst 90 dwdwah.xx - In response to an ICMP packet Echo Request sent with Echo Request id 100 and Echo Request sequence number 90, we want to send an ICMP Redirect to the host araya.xx to modify its routing table with the following data: the host pizza.death as a gateway to the host death.es, masking the packet source as if it was sent from infect.comx host. sing -red -S infect.comx -gw pizza.death -dest death.es -x host -prot icmp -ip_id 100 -ip_seq 90 araya.xx - We want to send an ICMP packet Destination Unreach to the host 10.2.3.4 saying that our TCP port number 20 connected with its TCP port 2100, is unreachable. We mask ourselves as host 10.1.1.1: sing -du -S 10.1.1.1 -x port-unreach -prot tcp -psrc 2100 -pdst 20 10.2.3.4 - We want to send an ICMP packet Destination Unreach to host 10.2.3.4 saying that the host inferno.hell and its TCP port 69, connected with his port TCP 666 in unreachable. We mask ourselves as gateway router.comx: sing -du -S router.comx -x host-unreach -prot tcp -psrc 666 -pdst 69 -orig inferno.hell 10.2.3.4 - We want to send a packet ICMP Source Quench to host ldg02.hell in response to a packet destinated to host ldg00 with UDP protocol, source port 100 and destination port 200. We mask ourselves as gateway 10.10.10.1: sing -sq -S 10.10.10.1 -prot udp -psrc 100 -pdst 200 -orig ldg00 ldg02.hell - We want to send an ICMP packet Time Exceeded to host ldg02.hell in response to a packet destinated to host ldg00 with UDP protocol, source port 100 and destination port 200. We mask as gateway ldg04.hell: sing -tx -S ldg04.hell -x frag -prot udp -psrc 100 -pdst 200 -orig ldg00 ldg02.hell - We want to send an ICMP packet Address Mask Request and wait 10 seconds between sending each packet. We mask the packet with source address of 10.2.3.4 and we send it to the address 10.0.1.255: sing -mask -S 10.2.3.4 -T 10 10.0.1.255 - We want to send an ICMP packet Information Request to host deep.hell: sing -info deep.hell - We want to send an ICMP packet Echo Request to host black.hell with the data pattern 'MyNameIsGump': sing -p MyNameIsGump black.hell - We want to send ICMP packet Echo Request to 10.12.0.255 with the following data pattern: D E A T H (blanks included). We will mask the source address as 192.168.0.255: sing -S 192.168.0.255 -p 'D E A T H' 10.12.0.255 - We want to send an ICMP packet Destination Unreach to host destination.death but sending it with an ICMP code bigger to the legal ones adding also 60K of garbage data: sing -du -x max -s 60000 destination.death - We send an ICMP Parameter Problem to host misery.es saying that the packet sent from the host dump.xorg with udp protocol, source port 13 and destination port 53, has an error on the IP header byte 13. We will also add all garbage bytes as possible: sing -S dump.xorg -param -ptr 13 -prot udp -psrc 13 -pdest 53 -s max misery.es - We want to send an ICMP packet Timestamp to host www.danz.hell with code 38 instead of code (0) as usual: sing -tstamp -x 38 www.danz.hell - Same as above without code 38 and using Loose Source Routing between the routers cisco, 10.13.1.1 and wakeup.man: sing -tstamp cisco@10.13.1.1@wakeup.man@www.danz.hell - Same as above using Strict Source Routing between the gateways: sing -tstamp cisco%10.13.1.1%wakeup.man%www.danz.hell - Using Record Route IP Option to see the route that takes to ftp.target.xx: sing -R ftp.target.xx

SEE ALSO
Postel, John, "Internet Control Message Protocol - DARPA Internet Program Protocol Specification", RFC 792, USC/Information Sciences Institute, September 1981. Mogul, Jeffrey and John Postel, "Internet Standard Subnetting Procedure", RFC 950, Stanford, USC/Information Sciences Institute, August 1985. Braden, Robert, "Requeriments for Internet Hosts - Communication Layers", RFC 1122, USC/Information Sciences Institute, October 1989. Deering, Stephen, "ICMP Router Discovery Messages", RFC 1256, Xerox PARC, September 1991. Baker, Fred, "Requeriments for IP Version 4 Routers", RFC 1812, Cisco Systems, June 1995. Arkin, Ofir, "ICMP usage in scanning", http://www.sys-security.com/archive/papers/ICMP_Scanning.pdf, Sys-Security Group, July 2000. The Linux source code, everything referent to network code and to ICMP protocol.

AUTHOR
The original ping command was written by Mike Muuss. sing is original from Alfredo Andres Omella, Slay <aandres@s21sec.com>