axlisten - monitor AX.25 traffic
axlisten [-8] [-a] [-c] [-h] [-i] [-p port] [-r] [-t] [-v]
Axlisten uses SOCK_PACKET facilities to provide a network monitor of
all AX.25 traffic heard by the system. Since KISS is implicitly
promiscuous no special driver configurations are needed.
This version displays standard AX.25, PE1CHL extended AX.25, NET/ROM,
Rose, ARP, IP, ICMP, TCP and UDP. It also displays IP, TCP, ICMP, TCP
and UDP encapsulated within NET/ROM frames. The program also displays
AX.25 and IP encapsulated within an IP frame, but see RFC1326 for
reasons not to do so.
Axlisten makes an attempt at decoding some of the more common routing
protocols. RSPF and RIP (both “normal” and G8BPQs RIP98) are traced.
JNOS style NET/ROM node polls are also displayed.
Axlisten can use colors to make the output more readable. The ncurses
library is used to accomplish this. Color support defaults to being
disabled, and the -c parameter is used to enable it.
-8 Indicates that the terminal is capable of printing 8-bit
characters. This parameter is required for the -i parameter
-a Allow for the monitoring of outgoing frames as well as
-c Enable color support.
-h Dump the data portion of the packet in both hexadecimal and
ASCII. The default is to display data as ASCII only.
-i Map IBM codepage 437 characters 128-158 to their ISO-Latin-1
equivalents. This is a hack for scandinavian users. This
parameter is only valid when used with the -8 and -c
-p port Monitor only those frames received on a particular port, by
default all AX.25 devices are monitored.
-r Dump the data portion in a "readable" fashion, which is more
suitable for tracing plaintext AX.25 traffic. CR-LF
conversion is done.
-t Displays a timestamp with each packet received.
-v Display the version.
axcall(1), mheard(1), beacon(1), ax25(4), netrom(4), rose(4),
Axlisten does not validate the checksums of frames that support them
(ie IP), therefore corrupt frames will be displayed with bogus values.
The MSS of a TCP frame that contains that option is not displayed.
Alan Cox GW4PTS <email@example.com>
Jonathan Naylor G4KLX <firstname.lastname@example.org>
Phil Karn KA9Q <email@example.com>
Heikki Hannikainen OH7LZB <firstname.lastname@example.org>