Sniffing a telnet session into a file ...

[RedTussock]

I operate a home made 1 wire weather station which I monitor using a very good app called OWW. OWW sends a txt line of data out on port 8891 on the localhost which can be read by telnet 'ing the localhost on that port. What I would love to do is establish a telnet session, take the 1 line result and write it to a file and eventually upload onto the net .. Has anyone here had a go at something like this .. below is the code I am working on ... and code I use to grab data from the MySQL server which OWW keeps fed as well.

#!/usr/bin/perl -w
#Telnet Script to read the OWW tcp port and write the output to a file
+ for upload to the net
#
#
use Net::Telnet ();
use Cwd;

open my $fh, '>', '/home/Smitty/scripts/perl/WLStickers.txt' or die $!
+;


{
    $t = new Net::Telnet (Timeout => 10,
                   Output_log => $ofile);

    
    $t->open("127.0.0.1 8891");
    
    $t->close;
}


exit 0

I acknowledge this is not working ... just not perl savvy enough to get it to go easily ... maybe the pixies will fix it overnite :-) Following is a script which was working uploading the required file, in the format requested by a local weather net group.

#!/usr/bin/perl -w
 use Net::FTP;
 use DBI;
 
 $dbh = DBI->connect('dbi:mysql:database','user','pass')
 or die "Connection Error: $DBI::errstr\n";
 $sql = "select concat_ws(',' , TIME_FORMAT(NZST,'%h:%i')  ,DATE_FORMA
+T(NZST,'%d/%m/%y'),t2,'',wdchill,rh,dp,bp,'',wdspd,ROUND(wddeg),rn,''
+,'','','',wdgst,'c|kmh|mb|mm') FROM tbl_owwdata ORDER BY wx_idx DESC 
+LIMIT 1";
 $sth = $dbh->prepare($sql);
 $sth->execute
 or die "SQL Error: $DBI::errstr\n";
 while (@row = $sth->fetchrow_array) {
 open (MYFILE, '>WL_stickertags.txt');
 print MYFILE "@row\n";
 close (MYFILE); 
 }
 

    $ftp = Net::FTP->new("some.where.com", Debug => 0)
      or die "Cannot connect to Simplehost: $@";

    $ftp->login("******",'*******')
      or die "Cannot login ", $ftp->message;

    $ftp->cwd("/a.b.c/folder")
      or die "Cannot change working directory ", $ftp->message;

    $ftp->put("WL_stickertags.txt")
      or die "put failed ", $ftp->message;

    $ftp->quit;
 
 exit 0

Of course it would be much more fun to snif the 1 wire net directly and format a web page with results and graphs etc. But small steps grasshopper ...

[zentara]

See Re^3: Want to communicate status of the last command to Windows machine

[aitap]

OWW sends a txt line of data out on port 8891 on the localhost which can be read by telnet 'ing the localhost on that port

You don't need to telnet to it. Just use IO::Socket::INET to connect to the host, read a text line from it and write it anywhere.

[RedTussock]

Even better ... :-)

[NetWallah]

If this is a simple "fetch one line" job, you can just use a bash command reading /dev/tcp to accomplish it.

See Using Bash's Built-in /dev/tcp File (TCP/IP).

In case you need it, there is also a /dev/udp.

[RedTussock]

Yes in fact OWW does do udp as well ... Is there actually a perl 1 wire tool ?.

[NetWallah]

A Google search for "perl 1 wire" leads to many hits including DigiTemp which is "is a simple to use program for reading values from 1-wire devices".

[zentara]

It also dawned on me last night that you don't need telnet to do this. In that train of thought, see Tk Realtime data aquisition

[RedTussock]

Yep that is all fine and dandy ... but what I have coming in of the 1 wire network is multiple 1 wire devices with uynique ID's ... what is coming out the tcp port on 8891 from oww looks like

Smitty@smittytech:~> telnet localhost 8891
Trying ::1...
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
11/10/12 , 18:36:27 , ,�C   ,    6.87,  KPH,     South   ,180.0
+  ,  8    , 0.00, mm
11/10/12 , 18:36:27 , ,�C   ,    6.00,  KPH,        SE   ,135.0
+  ,  6    , 0.00, mm
11/10/12 , 18:36:30 , ,�C   ,    5.91,  KPH,       SSE   ,157.5
+  ,  7    , 0.00, mm
11/10/12 , 18:36:32 , ,�C   ,    4.31,  KPH,     South   ,180.0
+  ,  8    , 0.00, mm
11/10/12 , 18:36:34 , ,�C   ,    4.26,  KPH,     South   ,180.0
+  ,  8    , 0.00, mm
11/10/12 , 18:36:37 , ,�C   ,    4.25,  KPH,     South   ,180.0
+  ,  8    , 0.00, mm
11/10/12 , 18:36:39 , ,�C   ,    5.09,  KPH,        SW   ,225.0
+  , 10    , 0.00, mm
11/10/12 , 18:36:41 , ,�C   ,    4.16,  KPH,        SE   ,135.0
+  ,  6    , 0.00, mm
11/10/12 , 18:36:44 , ,�C   ,    3.35,  KPH,        SW   ,225.0
+  , 10    , 0.00, mm
11/10/12 , 18:36:46 , ,�C   ,    4.21,  KPH,        SW   ,225.0
+  , 10    , 0.00, mm
11/10/12 , 18:36:48 , ,�C   ,    4.28,  KPH,       SSW   ,202.5
+  ,  9    , 0.00, mm
^C^C

So I either need to kill oww and read the device of the net and do all the 1W net comms using a perl script and hand the result into your suggested send script. Clever idea ... but I need to go deeper into the network comms, which means reinventing a wheel.

[zentara]

I don't know what oww is exactly, a c program? If my assumption is correct, oww reads the 1w net and reports it out on port 8891. Maybe you should see if oww has options to just print out to STDOUT instead of port 8891, if so you could run it with some Perl IPC, like a piped open or Open3, then let Perl send it out on a regular socket connection.

It may also be a McGiver hack, but you could have another Perl script on the oww machine to read port 8891, and relay it out a normal socket.

Can you get the source code to oww? You could hack it to wtite to STDOUT.