nemesis-dns(1) (usm)
nemesis-dns(1) General Commands Manual (usm) nemesis-dns(1)

NAME

nemesis-dnsDNS Protocol (The Nemesis Project)

SYNOPSIS

nemesis-dns [FlkvZ?] [-a NUM] [-A NUM] [-b NUM] [-d IFNAME] [-D ADDr] [-f FLAGS] [-F OPT] [-g FLAGS] [-H MAC] [-i ID] [-I ID] [-M MAC] [-o FILE] [-O FILE] [-P FILE] [-q NUM] [-r NUM] [-s NUM] [-S ADDR] [-t TOS] [-T TTL] [-u OFFSET] [-w SIZE] [-x PORT] [-y PORT]

DESCRIPTION

nemesis is designed to be a command line-based, portable human IP stack for UNIX-like and Windows systems. The suite is broken down by protocol, and should allow for useful scripting of injected packets from simple shell scripts.
nemesis-dns provides an interface to craft and inject DNS packets allowing the user to specify any portion of a DNS packet as well as lower-level IP and TCP/UDP packet information.

DNS OPTIONS

-A NUM
Specify the number of authoritative resource records in the DNS header.
-b NUM
Specify the number of answer resource records in the DNS header.
-g FLAGS
Specify the DNS flags in the DNS header.
-i ID
Specify the DNS ID in the DNS header.
-k
Use TCP instead of UDP when injecting DNS packets.
-P FILE
This will cause nemesis-dns to use the specified FILE as the payload when injecting DNS packets. For packets injected using the raw interface (where -d is not used), the maximum payload size is 65443 bytes for DNS packets injected using TCP, and 65455 for DNS packets injected using UDP. For packets injected using the link layer interface (where -d IS used), the maximum payload size is 1368 bytes for TCP DNS packets, and 1420 bytes for UDP DNS packets. Payloads can also be read from stdin by specifying -P- instead.
Windows systems are limited to a maximum payload size of 1368 bytes for TCP DNS packets and 1420 bytes for UDP DNS packets.
The payload file can consist of any arbitrary data though it will be most useful to create a payload resembling the structure of the DNS packet specified using the command-line options. In order to send real DNS packets, a payload containing the appropriate record data (as specified in the DNS header) must be created manually.
-q NUM
Specify the number of questions in the DNS header.
-r NUM
Specify the number of additional resource records in the DNS header.
-v
Display the injected packet in human readable form. Use twice to see a hexdump of the injected packet with printable ASCII characters on the right. Use three times for a hexdump without decoded ASCII.

TCP OPTIONS

-NUM
Specify the acknowledgement number (ACK number) in the TCP header.
-f FLAGS
Specify the TCP flags in the TCP header.
-fS
SYN
-fA
ACK
-fR
RST
-fP
PSH
-fF
FIN
-fU
URG
-fE
ECE
-fC
CWR
Flags can be combined in the form -fPA.
-o FILE
This will cause nemesis-dns to use the specified FILE as the options when building the TCP header for the injected packet. TCP options can be up to 40 bytes in length. The TCP options file must be created manually based upon the desired options. TCP options can also be read from stdin by specifying -o- instead.
-s NUM
Specify the sequence number in the TCP header.
-u OFFSET
Specify the urgent pointer offset in the TCP header.
-w SIZE
Specify the window size (bytes) in the TCP header.
-x PORT
Specify the TCP source port in the TCP header.
-y PORT
Specify the TCP destination port in the TCP header.

UDP OPTIONS

-x PORT
Source Port of injected packet.
-y PORT
Target Port of injected packet.

IP OPTIONS

-D ADDR
Specify the destination IP address in the IP header.
-F OPT
Specify the fragmentation options in the IP header:
-FD
don't fragment
-FM
more fragments
-FR
reserved flag
-F offset
 
IP fragmentation options can be specified individually or combined into a single argument to the -F command line switch by separating the options with commas (eg. -FD,M) or spaces (eg. -FM 223). The IP fragmentation offset is a 13-bit field with valid values from 0 to 8189. Don't fragment (DF), more fragments (MF) and the reserved flag (RESERVED or RB) are 1-bit fields.
NOTE: Under normal conditions, the reserved flag is unset.
-ID
Specify the IP ID in the IP header.
-O FILE
This will cause nemesis-dns to use the specified FILE as the options when building the IP header for the injected packet. IP options can be up to 40 bytes in length. The IP options file must be created manually based upon the desired options. IP options can also be read from stdin by specifying -O- instead.
-S -ADDR
Specify the source IP address in the IP header.
-t -TOS
Specify the IP type-of-service (TOS) in the IP header. Valid type of service values:
2
Minimize monetary cost
4
Maximize reliability
8
Maximize throughput
24
Minimize delay
NOTE: Under normal conditions, only one type of service is set within a packet. To specify multiple types, specify the sum of the desired values as the type of service.
-T TTL
Specify the IP time-to-live (TTL) in the IP header.

DATA LINK OPTIONS

-d IFNAME
Specify the name (for UNIX-like systems) or the number (for Windows systems) of the IFNAME to use (eg. fxp0, eth0, hme0, 1).
-H MAC
Specify the source MAC address, (XX:XX:XX:XX:XX:XX).
-M MAC
Specify the destination MAC address, (XX:XX:XX:XX:XX:XX).
-Z
Lists the available network interfaces by number for use in link-layer injection.
NOTE: This feature is only relevant to Windows systems.

DIAGNOSTICS

Nemesis-dns returns 0 on a successful exit, 1 if it exits on an error.

SEE ALSO

nemesis-arp(1), nemesis-dhcp(1), nemesis-ethernet(1), nemesis-icmp(1), nemesis-igmp(1), nemesis-ip(1), nemesis-ospf(1), nemesis-rip(1), nemesis-tcp(1), nemesis-udp(1).

AUTHORS

Mark Grimes <mark@stateful.net> and
Jeff Nathan <jeff@snort.org>

BUGS

An interface for users to create DNS packet payloads should be created.
Please report bugs at https://github.com/troglobit/nemesis/issues
December 2, 2019