Lector de Feeds
kfourinline-24.05.0-1.mga10.src.rpm
kubrick-24.05.0-1.mga10.src.rpm
kubrick-24.05.0-1.mga10.src.rpm
lskat-24.05.0-1.mga10.src.rpm
lskat-24.05.0-1.mga10.src.rpm
kitinerary-24.05.0-2.mga10.src.rpm
kitinerary-24.05.0-2.mga10.src.rpm
kdeedu-data-24.05.0-1.mga10.src.rpm
kdeedu-data-24.05.0-1.mga10.src.rpm
lokalize-24.05.0-1.mga10.src.rpm
lokalize-24.05.0-1.mga10.src.rpm
HOWTO: NULL Modem TCP/IP network connection between Linux and Windows
Linux PPP server
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The first step is to install the pppd demon and optionally the mgetty to use it on dialup modem, but this howto only covers the null modem (serial) part.
Once installed you must to create the following files:
/etc/sysctl.conf
net.ipv4.ip_forward=1/etc/ppp/options
# demon persist noauth auth # compress bsdcomp 12,15 deflate 12,15 # common options proxyarp lock passive lcp-echo-interval 8 lcp-echo-failure 6 nologfd crtscts local # Windows compat connect 'chat TIMEOUT 20000 CLIENT CLIENTSERVER' # port settings /dev/ttyS0 115200/etc/ppp/options.ttyS0
# server ip : client ip 10.0.2.15:10.0.2.100 netmask 255.255.255.0 ms-dns 77.88.8.8/etc/ppp/pap-secrets
# user server password ip user * userPass *You can launch the pppd demon on init or inittab.
Linux PPP client
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Now in the client you must also install the pppd demon and create the following files:
/etc/ppp/options
# common options defaultroute lock passive lcp-echo-interval 8 lcp-echo-failure 6 nologfd crtscts local # Windows compat connect 'chat -v -f /etc/ppp/win.chat' # port settings /dev/ttyS0 115200/etc/ppp/options.ttyS0
user user/etc/ppp/win.chat
TIMEOUT 10 '' CLIENT\c**Windows PPP client
------------------**
If you use Windows, also can connect to the network. The first step is download a null modem driver (e.g. MDMCBXNT.INF) and install it.
Now only is necessary create a new phone connection with the "NT Direct Connection" modem on 115200 bauds.
NCN2k15 CTF "CivilWar" writeup
In the past NCN2k15, all CTF participants received these files: a png image and a ogg sound. Listening that sound it's easily to advert that this is encoded data. Also the image is like a real WWII crypt order.
As the order said, this probably is an encoded RTTY, morse or hellschreiber. Maybe enigma crypted, because that was the WWII standard.
The first step is to convert the ogg file to a standard wav. Next, open it in Signals Analyzer
The image shows amplitude pulses, like morse but faster that a human can handle ;-)
A good ear immediately recognize it as an Hellschreiber signal but this is not fun and now we will to analyze it as a unknown signal.
All pulses seems to be in blocks of four bits, good synchronized and spaced. Also we don't see any sync signal, probably is a OOK mode based on a perfect sender timing. If we remember all those known OOK modes, the Hellschreiber is very similar. In the upper image we can see how to demodulate it, basically it is an matrix of pixels based on the amplitude value.
The fill order is from A (7 to 1), next B, etc. Here are a very good explanation.
Demodulate this file manually is a very tedious work for this we will use the fldigi.
The message is: YJIPYVQHAADFWOETWQLBRUEKMKBNNQQMMMIFXDKFCNBFPVOOOYKSECZUJRGGMQQVNCRAJBNDQTHOFGNT
Also we have the crib from the recovered document.
The enigma machine don't have space bar, and some operators used the X char as a space (others simply didn't spaced the words)
Searching for "enigma solver" shows this web page as the first result. This page does some type of black magic and have a very good result without crib.
This result is not valid because the crib is not equal ( but i must review the code and "take ideas" for my enigma-solver :p )
Now my awesome hacky-5minute-tool! (please don't review the code... is a complete mess!)
Another tools works too! for example, i'd based on this paper and code
We use the crib (X as spaces)
The "enigma-solver" program feeds from "dict/current.txt" for spell checking and give a "rank" according to number of words in the dictionary. The first message seems valid.
Sorry German girls, but my german skillz are awful.
The code is "ORRMBASDHEEEHNQSHOLJVNFF" but this is not a valid key... the last process is a MD5 and TADA!
P.D: Guys, i'm so sorry about the downtime in the CTF day... in my country all electric suppliers are a fucking piece of shit. :(
