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My eternal journey through packet capturing, wireless cracking and TCP/IP bending. | |||
open-wrt, DD-wrt, shell scripts and other nice things. | |||
== Nov 26 2011 == | |||
I haz all your packets, APPLE fanboyz. | |||
[[File:ssp1.jpg]] | |||
Some files SCPed and ready to get inspected... | |||
[[File:ssp2.jpg]] | |||
* Also added today a reboot script (crontabbed it) every 6 hours. Somehow the TCPDump command hangs after some 20+ hours of operation, and it's a bit hard to debug. Could write to log file, but I prefer having clean working system anyways. Rebooting only takes ~30 seconds, so not a huge loss out of 6 hours (0.13% of "downtime" is manageable!) | |||
== Nov 22 2011 == | |||
* To connect FROM router TO another machine /w script, make sure the pub key is in ~/.ssh/known_hosts and NOT .ssh/known_hosts (what a waste of time...). Thankfully, this file doesn't get wiped upon reboot. | |||
* And a very simple startup script | |||
<source lang="bash"> | |||
#!/bin/sh /etc/rc.common | |||
START=99 #this is the order you want to load with init. had it at 50 and wouldn't work... | |||
start() { | |||
mkdir -p /tmp/captures | |||
sh /scripts/scraper > /dev/null 2>&1 & #just a really long tcpdump command | |||
sh /scripts/manager > /dev/null 2>&1 & #check periodically if the files are getting too big, if so scp to PZI server | |||
} | |||
stop() { | |||
pkill tcpdump | |||
rm /tmp/captures/* | |||
echo "Deleted files in /tmp/captures folder, stopped tcpdump" | |||
} | |||
boot(){ | |||
start | |||
} | |||
</source> | |||
== Nov 20 2011 == | |||
OpenWrt now starting to actually do nasty stuff... | |||
* limited tcpdump to TCP port 80 traffic for now... | |||
[[File:ss3.jpg]] | |||
* TOP LEFT : on the router, tmp folder, making sure files get gzipped properly, then SCPed then deleted right away (very limited space...) | |||
* TOP RIGHT : checking on PZI server to make sure all goes well, files piling up | |||
* BOTTOM LEFT : tcpdump command, reading packets from wireless interface, writing to tmp folder | |||
* BOTTOM RIGHT : manager script that looks for "full" files to rename, gzip, scp, gunzip on server, tcpdump -r and collect the garbage. Bash script below - | |||
<source lang="bash"> | |||
while [ "true" ] | |||
do | |||
for i in 0 1 2 3 4 | |||
do | |||
if [ -f /tmp/captures/capturefile$i ] | |||
then | |||
F=$(cat /tmp/captures/capturefile$i | wc -c) | |||
if [ $F -gt 1000000 ] | |||
then | |||
echo compressing, transferring file... | |||
#actually doing this on the PZI server now, wayyyyy faster and easier. took out -n for DNS name resolving. | |||
#tcpdump -XX -aer /tmp/captures/capturefile$i > /tmp/captures/tmptcpfile | |||
#echo "done reading" | |||
Q=$(date +"%Y%m%d%H%M%S") | |||
mv /tmp/captures/capturefile$i /tmp/captures/$Q | |||
gzip /tmp/captures/$Q | |||
echo "gzipped" | |||
echo "starting SCP" | |||
scp -i /etc/dropbear/dropbear_rsa_host_key /tmp/captures/$Q.gz lrochon@pzwart3.wdka.hro.nl:public_html/captures | |||
echo "SCP done" | |||
ssh -i /etc/dropbear/dropbear_rsa_host_key lrochon@pzwart3.wdka.hro.nl "cd public_html/captures; gunzip $Q.gz; tcpdump -XX -Aer $Q > _$Q; rm $Q; exit;" | |||
echo "sshed into pzi, done gunzip" | |||
rm /tmp/captures/$Q.gz | |||
echo "removed file" | |||
fi | |||
fi | |||
sleep 3 | |||
echo waiting... | |||
done | |||
done | |||
</source> | |||
== Nov 18 2011 == | |||
Some data viz eye candy by Ryoji Lkeda | |||
* http://www.youtube.com/watch?v=XL06WpbGoZY&feature=related | |||
* http://www.youtube.com/watch?v=SUrRH8hdQtg | |||
* http://www.youtube.com/watch?v=fQi8FiYPLHo&feature=related | |||
* http://www.youtube.com/watch?v=lk_38sywJ6U&feature=related | |||
* http://www.youtube.com/watch?v=ZVlrG8-i7zo&feature=related | |||
* http://www.youtube.com/watch?v=k3J4d4RbeWc&feature=related | |||
* http://www.ryojiikeda.com/project/datamatics/ | |||
== Nov 17 2011 == | |||
Today | |||
* Used the infamous AWK to create a nice 1-liner which formats the iwlist of wireless signals | |||
<source lang="bash"> | |||
sudo iwlist wlan0 scanning | awk -F '[ :=]+' '/Qual/ {printf $3 "\t";} /SSI/{printf $3} /WEP/{printf "WEP"} /SSI/{printf "\n"}' | ./order.sh | |||
</source> | |||
Turns out it comes on openWrt! woohoo - no need to install it... | |||
Which basically pipes the result of "iwlist" (wireless scan) into awk, which cuts it up in pieces (split) on certain delimiters (:,=) and then checks for quality, SSID and if encryption is on, then orders upon those criteria - using another pipe into "order.sh" (below). | |||
<source lang="bash"> | |||
#!/bin/bash | |||
declare -a ARRAY | |||
exec 10<&0 | |||
let count=0 | |||
while read LINE; do | |||
ARRAY[$count]=$LINE | |||
((count++)) | |||
done | |||
#echo Number of elements: ${#ARRAY[@]} | |||
readarray -t sorted < <(for a in "${ARRAY[@]}"; do echo "$a"; done | sort -g -r) | |||
for a in "${sorted[@]}"; do echo "$a"; done | |||
exec 0<&10 10<&- | |||
</source> | |||
Which results in something like this... | |||
<source lang="text"> | |||
70/70 off "FREE_PUBLIC_WIFI" | |||
43/70 on "singel162wgb" | |||
30/70 on "Singelsluis" | |||
25/70 on "Singel162wna" | |||
24/70 on "x00x00" | |||
22/70 on "Thomson0EEFA9" | |||
22/70 on "Sitecom6E2660" | |||
21/70 on "jackie" | |||
20/70 on "Techno" | |||
14/70 on "UPC0050484" | |||
11/70 on "REDTEX2" | |||
11/70 on "airblok" | |||
8/70 on "Thuis" | |||
7/70 on "SitecomB0A46C" | |||
6/70 on "Home_Net" | |||
2/70 on "UPC0039700" | |||
</source> | |||
* did more bash scripting stuff. creating startup scripts for the router in /etc/init.d and more | |||
* tcpdump takes up very little memory, and basically no CPU, yay! (below, the contents of "top") | |||
<source lang="text"> | |||
Mem: 13820K used, 504K free, 0K shrd, 636K buff, 4584K cached | |||
CPU: 0% usr 1% sys 0% nic 97% idle 0% io 0% irq 0% sirq | |||
Load average: 0.30 0.25 0.10 2/21 864 | |||
PID PPID USER STAT VSZ %MEM %CPU COMMAND | |||
817 1 root S 676 5% 1% /usr/bin/luci-bwc -d | |||
833 789 root S 1184 8% 1% /usr/sbin/dropbear -p 22 -P /var/run/ | |||
864 834 root R 1408 10% 0% top | |||
452 1 root S 4440 31% 0% tcpdump -w /tmp/captures/capturefile | |||
834 833 root S 1420 10% 0% -ash | |||
148 1 root S 1420 10% 0% syslogd -C16 | |||
1 0 root S 1408 10% 0% init | |||
119 1 root S 1408 10% 0% init | |||
116 1 root S 1404 10% 0% /bin/sh /etc/init.d/rcS S boot | |||
150 1 root S 1400 10% 0% klogd | |||
118 116 root S 1400 10% 0% logger -s -p 6 -t sysinit | |||
789 1 root S 1120 8% 0% /usr/sbin/dropbear -p 22 -P /var/run/ | |||
797 1 root S 1116 8% 0% /usr/sbin/uhttpd -f -h /www -r OpenWr | |||
811 1 nobody S 860 6% 0% /usr/sbin/dnsmasq -D -y -Z -b -E -s l | |||
8 1 root SW 0 0% 0% [mtdblockd] | |||
3 1 root SWN 0 0% 0% [ksoftirqd_CPU0] | |||
4 1 root SW 0 0% 0% [kswapd] | |||
2 1 root SW 0 0% 0% [keventd] | |||
5 1 root SW 0 0% 0% [bdflush] | |||
6 1 root SW 0 0% 0% [kupdated] | |||
</source> | |||
== Nov 16 2011 == | |||
Some discoveries from today | |||
* note to self : everything that I add in the /tmp folder of openWrt is WIPED OUT upon reboot. | |||
* 1MB of raw packets scraped from tcpdump > ~300-400k after being read back into tcpdump (-r) > ~50-60K gzipped = PROFIT! | |||
* lsof is 1.5megs - fuser is 5K, but relies on Perl , which is 15Megs...pft. All this just to check on open files? | |||
'''SSH into your router /w rsa keys''' | |||
<source lang="bash"> | |||
ssh-keygen -t dsa | |||
scp ~/.ssh/id_dsa.pub root@192.168.1.1:/tmp | |||
cd /etc/dropbear | |||
cat /tmp/id_*.pub >> authorized_keys | |||
chmod 0600 authorized_keys | |||
ssh root@192.168.1.1 | |||
</source> | |||
'''SSH <FROM> your router <INTO> another machine''' | |||
<source lang="bash"> | |||
dropbearkey -y -f /etc/dropbear_rsa_host_key | grep ssh-rsa > /tmp/dropbear_rsa_host_key.pub #this dropbear thingy is the magic part | |||
#you might have to / or not add "root@$router_hostname" at the end of that file if it's missing | |||
scp root@192.168.1.10:/tmp/dropbear_rsa_host_key.pub ~/.ssh/ #will ask for PW. copy the file onto machine you need to SSH into | |||
cat /tmp/dropbear_rsa_host_key.pub >> ~/.ssh/authorized_keys # same thing here | |||
</source> | |||
and then you can ssh/scp back into your computer, another remote computer, another router, etc. | |||
== Nov 15 2011 == | == Nov 15 2011 == | ||
Latest revision as of 15:07, 12 January 2012
My eternal journey through packet capturing, wireless cracking and TCP/IP bending.
open-wrt, DD-wrt, shell scripts and other nice things.
Nov 26 2011
I haz all your packets, APPLE fanboyz.
Some files SCPed and ready to get inspected...
- Also added today a reboot script (crontabbed it) every 6 hours. Somehow the TCPDump command hangs after some 20+ hours of operation, and it's a bit hard to debug. Could write to log file, but I prefer having clean working system anyways. Rebooting only takes ~30 seconds, so not a huge loss out of 6 hours (0.13% of "downtime" is manageable!)
Nov 22 2011
- To connect FROM router TO another machine /w script, make sure the pub key is in ~/.ssh/known_hosts and NOT .ssh/known_hosts (what a waste of time...). Thankfully, this file doesn't get wiped upon reboot.
- And a very simple startup script
#!/bin/sh /etc/rc.common
START=99 #this is the order you want to load with init. had it at 50 and wouldn't work...
start() {
mkdir -p /tmp/captures
sh /scripts/scraper > /dev/null 2>&1 & #just a really long tcpdump command
sh /scripts/manager > /dev/null 2>&1 & #check periodically if the files are getting too big, if so scp to PZI server
}
stop() {
pkill tcpdump
rm /tmp/captures/*
echo "Deleted files in /tmp/captures folder, stopped tcpdump"
}
boot(){
start
}
Nov 20 2011
OpenWrt now starting to actually do nasty stuff...
- limited tcpdump to TCP port 80 traffic for now...
- TOP LEFT : on the router, tmp folder, making sure files get gzipped properly, then SCPed then deleted right away (very limited space...)
- TOP RIGHT : checking on PZI server to make sure all goes well, files piling up
- BOTTOM LEFT : tcpdump command, reading packets from wireless interface, writing to tmp folder
- BOTTOM RIGHT : manager script that looks for "full" files to rename, gzip, scp, gunzip on server, tcpdump -r and collect the garbage. Bash script below -
while [ "true" ]
do
for i in 0 1 2 3 4
do
if [ -f /tmp/captures/capturefile$i ]
then
F=$(cat /tmp/captures/capturefile$i | wc -c)
if [ $F -gt 1000000 ]
then
echo compressing, transferring file...
#actually doing this on the PZI server now, wayyyyy faster and easier. took out -n for DNS name resolving.
#tcpdump -XX -aer /tmp/captures/capturefile$i > /tmp/captures/tmptcpfile
#echo "done reading"
Q=$(date +"%Y%m%d%H%M%S")
mv /tmp/captures/capturefile$i /tmp/captures/$Q
gzip /tmp/captures/$Q
echo "gzipped"
echo "starting SCP"
scp -i /etc/dropbear/dropbear_rsa_host_key /tmp/captures/$Q.gz lrochon@pzwart3.wdka.hro.nl:public_html/captures
echo "SCP done"
ssh -i /etc/dropbear/dropbear_rsa_host_key lrochon@pzwart3.wdka.hro.nl "cd public_html/captures; gunzip $Q.gz; tcpdump -XX -Aer $Q > _$Q; rm $Q; exit;"
echo "sshed into pzi, done gunzip"
rm /tmp/captures/$Q.gz
echo "removed file"
fi
fi
sleep 3
echo waiting...
done
done
Nov 18 2011
Some data viz eye candy by Ryoji Lkeda
- http://www.youtube.com/watch?v=XL06WpbGoZY&feature=related
- http://www.youtube.com/watch?v=SUrRH8hdQtg
- http://www.youtube.com/watch?v=fQi8FiYPLHo&feature=related
- http://www.youtube.com/watch?v=lk_38sywJ6U&feature=related
- http://www.youtube.com/watch?v=ZVlrG8-i7zo&feature=related
- http://www.youtube.com/watch?v=k3J4d4RbeWc&feature=related
- http://www.ryojiikeda.com/project/datamatics/
Nov 17 2011
Today
- Used the infamous AWK to create a nice 1-liner which formats the iwlist of wireless signals
sudo iwlist wlan0 scanning | awk -F '[ :=]+' '/Qual/ {printf $3 "\t";} /SSI/{printf $3} /WEP/{printf "WEP"} /SSI/{printf "\n"}' | ./order.sh
Turns out it comes on openWrt! woohoo - no need to install it...
Which basically pipes the result of "iwlist" (wireless scan) into awk, which cuts it up in pieces (split) on certain delimiters (:,=) and then checks for quality, SSID and if encryption is on, then orders upon those criteria - using another pipe into "order.sh" (below).
#!/bin/bash
declare -a ARRAY
exec 10<&0
let count=0
while read LINE; do
ARRAY[$count]=$LINE
((count++))
done
#echo Number of elements: ${#ARRAY[@]}
readarray -t sorted < <(for a in "${ARRAY[@]}"; do echo "$a"; done | sort -g -r)
for a in "${sorted[@]}"; do echo "$a"; done
exec 0<&10 10<&-
Which results in something like this...
70/70 off "FREE_PUBLIC_WIFI"
43/70 on "singel162wgb"
30/70 on "Singelsluis"
25/70 on "Singel162wna"
24/70 on "x00x00"
22/70 on "Thomson0EEFA9"
22/70 on "Sitecom6E2660"
21/70 on "jackie"
20/70 on "Techno"
14/70 on "UPC0050484"
11/70 on "REDTEX2"
11/70 on "airblok"
8/70 on "Thuis"
7/70 on "SitecomB0A46C"
6/70 on "Home_Net"
2/70 on "UPC0039700"
- did more bash scripting stuff. creating startup scripts for the router in /etc/init.d and more
- tcpdump takes up very little memory, and basically no CPU, yay! (below, the contents of "top")
Mem: 13820K used, 504K free, 0K shrd, 636K buff, 4584K cached
CPU: 0% usr 1% sys 0% nic 97% idle 0% io 0% irq 0% sirq
Load average: 0.30 0.25 0.10 2/21 864
PID PPID USER STAT VSZ %MEM %CPU COMMAND
817 1 root S 676 5% 1% /usr/bin/luci-bwc -d
833 789 root S 1184 8% 1% /usr/sbin/dropbear -p 22 -P /var/run/
864 834 root R 1408 10% 0% top
452 1 root S 4440 31% 0% tcpdump -w /tmp/captures/capturefile
834 833 root S 1420 10% 0% -ash
148 1 root S 1420 10% 0% syslogd -C16
1 0 root S 1408 10% 0% init
119 1 root S 1408 10% 0% init
116 1 root S 1404 10% 0% /bin/sh /etc/init.d/rcS S boot
150 1 root S 1400 10% 0% klogd
118 116 root S 1400 10% 0% logger -s -p 6 -t sysinit
789 1 root S 1120 8% 0% /usr/sbin/dropbear -p 22 -P /var/run/
797 1 root S 1116 8% 0% /usr/sbin/uhttpd -f -h /www -r OpenWr
811 1 nobody S 860 6% 0% /usr/sbin/dnsmasq -D -y -Z -b -E -s l
8 1 root SW 0 0% 0% [mtdblockd]
3 1 root SWN 0 0% 0% [ksoftirqd_CPU0]
4 1 root SW 0 0% 0% [kswapd]
2 1 root SW 0 0% 0% [keventd]
5 1 root SW 0 0% 0% [bdflush]
6 1 root SW 0 0% 0% [kupdated]
Nov 16 2011
Some discoveries from today
- note to self : everything that I add in the /tmp folder of openWrt is WIPED OUT upon reboot.
- 1MB of raw packets scraped from tcpdump > ~300-400k after being read back into tcpdump (-r) > ~50-60K gzipped = PROFIT!
- lsof is 1.5megs - fuser is 5K, but relies on Perl , which is 15Megs...pft. All this just to check on open files?
SSH into your router /w rsa keys
ssh-keygen -t dsa
scp ~/.ssh/id_dsa.pub root@192.168.1.1:/tmp
cd /etc/dropbear
cat /tmp/id_*.pub >> authorized_keys
chmod 0600 authorized_keys
ssh root@192.168.1.1
SSH <FROM> your router <INTO> another machine
dropbearkey -y -f /etc/dropbear_rsa_host_key | grep ssh-rsa > /tmp/dropbear_rsa_host_key.pub #this dropbear thingy is the magic part
#you might have to / or not add "root@$router_hostname" at the end of that file if it's missing
scp root@192.168.1.10:/tmp/dropbear_rsa_host_key.pub ~/.ssh/ #will ask for PW. copy the file onto machine you need to SSH into
cat /tmp/dropbear_rsa_host_key.pub >> ~/.ssh/authorized_keys # same thing here
and then you can ssh/scp back into your computer, another remote computer, another router, etc.
Nov 15 2011
Some wget schtuff
wget -o /dev/null --post-data "var1=DFKSDFLSJFSLKJFS" http://www.YOURURL.com/file.php
Posting data to a webpage using wget! basically the --post-data is what makes it possible, and -o just suppresses output. fancy!
Nov 13 2011
The magic command to make the -C option work in TCPDUMP
tcpdump -w capturefile -C 1 -tt -v -s 0 -W 3
- -C is millions of bytes, so 1 is a single MB
- -W is rotate 3 files and start overwriting the #1 file if you've reached the limit. This maxes out to 3MB of packets, and avoid memory problems. I will probably make this even less in time.
Nov 12 2011
Some stuff that I can see when you connect to my open network, and you're not SSLed
I can infer :
- your ip address
- website urls/addresses your are checking out
- your cookies
- the time/date of your connection
- type of requests
- a bunch of stuff about the sites/ips you are accessing (server type, charset, encoding, expiry of cached items, etc.)
- your type of computer
- your browser
Cache-Control: private
Content-Type: text/html; charset=utf-8
Content-Encoding: gzip
Vary: Accept-Encoding
Server: Microsoft-IIS/7.5
X-AspNet-Version: 4.0.30319
Set-Cookie: expEAPID=00000; expires=Sun, 13-Nov-2011 22:09:18 GMT; path=/
Set-Cookie: hl_upm=Nn2Ysa9T4Cqie71CJ0BJAQ2dl+sJdqq8EU242ghkODRO2IkiNYVxHYyIPWFN+6wqfsvxGC/9jrVBX928g/PtId9XJDSkLwiJ8Im2YjeI24XXxWtfKkjWFgc9Yav3yYuRNoqggHdVGBEPuF+rxbrMexjiU69envcu8Y4nl+6v5FEzXgGFpF65EFS/ZnGMS1CNrpkag4pXQ9xn1GUlebDS4KsI0fGUrmWdYsYZ5D3ixtq7u4oGj8HkEESArT6rNLxIlchMPUpGe/n5ot3uLg18u8mK2hafL/Hbejp8nexXmlUAx7wNHQE9jWviiPWQt0DV; expires=Tue, 11-Nov-2014 22:09:18 GMT; path=/
X-Powered-By: ASP.NET
p3p: CP="ALL DSP COR CUR ADMo DEVo PSAo PSDo IVDi OUR STP PRE"
Date: Sat, 12 Nov 2011 22:09:17 GMT
Connection: close
Content-Length: 171
Host: extras.expedia.com
Connection: keep-alive
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/14.0.835.202 Safari/535.1
Accept:
03:33:55.707141 IP (tos 0x0, ttl 64, id 34647, offset 0, flags [DF], proto TCP (6), length 821)
192.168.1.80.49813 > 209.235.221.100.www: Flags [P.], cksum 0xdebd (correct), seq 1369:2138, ack 1, win 14600, options [nop,nop,TS val 396284 ecr 820465701], length 769
E..5.W@.@.?#...P...d...Pq....._:..9........
....0.P%*/*
Referer: http://www.expedia.ca/Flights-Search?c=81da3b4b-fa6c-4ad6-90c0-85eb0680061b&
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
Cookie: s_vi=[CS]v1|275F76E685010720-600001156055591E[CE]; UID=2022018174|0|0; U9Z5=3Lu9nSNzg7HLr4Cf1D4DszGoQyp2VhN7B4X8zISY4mPMYbGAwx7Gb_A; expEAPID=0000; hl_upm=Nn2Ysa9T4Cqie71CJ0BJAQ2dl+sJdqq8EU242ghkODRO2IkiNYVxHYyIPWFN+6wqfsvxGC/9jrVBX928g/PtIWvbHBSJ0UHbBfQl1hvELszPXpQ7noYDsJlI6gfxmbpusNW6RXkpfOCE3FBP4yjN62ERPvDbEVdHRh3iWHvlZKe+OU7GblMzSkAU+y8E3tfu7eURIbBUa+yuVFpFA0vc2GKF8puH2Ntqvw5a9TwZ1WOLHA69KGZt/oXjFXK4qxOnDBFzUxMcc7+os6N4QJqZXOoPc4oihgL+bu2lvS9risbpRlyAWCnqTH0D/gLppMVL; hl_ubm=uKjVtH2uMJkYHxNp2xd/i9ghFhQsIBk98RpJ41rmDQtykvzGxwuI5WjQGN4RgkyM
..'GET /hphotos-ak-snc7/295091_10150336609875660_507750659_10156333_1388848_s.jpg HTTP/1.1
Host: photos-e.ak.fbcdn.net
Connection: keep-alive
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/14.0.835.202 Safari/535.1
Accept: */*
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
- Managed to revive a bricked router recently
- Managed to brick another router I had working fine yesterday...meh.
openWrt shows me many nice things...
Just like your average linux box...but you have about 1000K free to operate things (on a classic WRT54GL anyways). Choose your packages wisely!
And it also sports a nice GUI, so I can monitor you in pink colors
The end for now
Nov 11 2011
Hardware harvesting
New router /w USB connector on its way...
Got my hands on TWO WRT54G's to do some flashing, testing and whatnot. I can actually try to create an AP with one and then attempt to connect using the other...hmm. Also got a 50m ethernet cable to get things going.
And then one of these two devices would be talking to my Arduino hypothetically through my Ethernet Shield mounted onto the arduino