stas'den - music

The Pirate Bay un-SSL

Thu, 31 Jul 2008 11:05:20 -0300

Theory

Recently, the world saw The Pirate Bay offering SSL encryption on their server. This means that your ISP won't know anymore which torrent you are downloading, right? Wrong.
HTTPS is quite useless for protecting static and public content. By static, I do mean the .torrent file itself. It is always the same. By public, I do mean than one doesn't need any kind of authentication to pick up the content. It's always the same, for everyone. For crawlers, too.
So, one could easily index (a portion of) The Pirate Bay torrent database by the Content-Length. Then, one could intercept some encrypted traffic between some machine(s) within his/her network and the torrents.thepiratebay.org server. Knowing both (encrypted) request and response lengths, it is possible to get a quite reliable list of matches from the previously indexed torrent list.

Practice

Don't try this at work, or you might hurt yourself

Use Wireshark to capture some torrent downloads. Torrents are hosted on a separate server, which makes the task easier yet. Just use the following capture filter: "tcp and port 443 and host torrents.thepiratebay.org"
Now, just go with the stream ("Follow TCP Stream" for the packet you suspect belongs to the torrent download. This will create another filter, just like "(ip.addr eq 192.168.0.10 and ip.addr eq 83.140.176.156) and (tcp.port eq 2157 and tcp.port eq 443)")
Just save the displayed stream anywhere else (pcap1.pcap sounds nice)
Now, use my quick&dirty TPB-TLSlen.pl Perl script to get the request/response lengths:
```
perl TPB-TLSlen.pl pcap1.pcap
```
Yeah, I know, it is nasty. It only supports the TLS cypher. And it simply calls the tshark (the command line version of Wireshark) to parse it's output.
Now, just paste the REQ and RES values below
(note that the REQ value is optional, setting it to 0 simply ignores the request size for matching)

Note that you are able to fine-tune the maximum and minimum header sizes. For the response, the headers are almost the same all the time. The only thing that varies is the decimal representation of the file length and age. (Un)fortuately, the request headers do vary for different browsers and referring pages. However, knowing the request size still helps a bit, specially if the torrent's filename was huge

Precision

The following size distribution chart was generated using the database with ~80K torrents:

The most common torrent size is ~14 KB, and it's easy to figure out that such torrents represent the shared 700 MB files
There's also a major peak for the 454 bytes torrents. However, bigger torrents are less common, thus, the size detection technique becomes more precise. Now, the average "distance" between torrent sizes is ~60 bytes (at least for the sample I've collected). So, adding a cookie with the random size up to 128 bytes will disrupt the size matching detection a lot. The request size disruption is even easier: the largest torrent URI I've found was 150 bytes-wide. Thus, padding every request URI to match 150 characters is enough to make the requests completely indistinguishable. Joining the pieces (the padding add-on strings are bold):

GET /4319199/[a4e]Ghost_in_the_Shell_TV_01-26.4319199.TPB.torrent?nVM2UGfcG533un4ym70eT2
9r0WwBLYdmFCNN+UTV/hiJ7EAXdFU5KfdWHpkB5lXaCmITsACKOPVyjmpbaOB+CrI5 HTTP/1.1
Host: torrents.thepiratebay.org
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.1) Gecko/2008070208
 Firefox/3.0.1
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: https://thepiratebay.org/recent
Cookie: language=pt_BR; country=BR; PHPSESSID=ad6cb7e414c8dc88e0c2444f6215165a

HTTP/1.1 200 OK
Content-Type: application/x-bittorrent
Etag: "2198642509"
Last-Modified: Mon, 28 Jul 2008 22:28:59 GMT
Server: lighttpd
Content-Length: 91601
Date: Mon, 28 Jul 2008 22:37:56 GMT
X-Varnish: 108010229 107999438
Age: 253
Via: 1.1 varnish
Connection: keep-alive
Set-Cookie: p=68eOfxOC7JwBYcMe1RJWC4Z5PV/lJzqJORW8KROPMH9zQhszSjFnRp2tsNWEoyabWAloneUaoz
MxYtx4hoM9MZUKE/7wGzC3ZKLEZdppG4og3W; expires=Mon, 28-Jul-2008 22:37:56 GMT; path=/;
 domain=torrents.thepiratebay.org

(binary torrent data)

Solution

Use a constant padding in the .torrent files. This messes things a bit, but stills ineffective. The only advantage is not messing up with the server
Patch the lighttpd server so it sends a non-lasting cookie with a random size.

Thanks

MEGA Hospedagem, for the network resources provided for this tiny research
http://www.warchalking.com.br/, for the inspiration

Encrypted session data

Possible matches

The Pirate Bay URL	strlen(URI)	torrent size
0 matches
Torrents indexed: 111604

my ring tones

Wed, 03 Jan 2007 23:12:36 -0200

A collection of the ring tones I made for my Sony Ericsson T68i mobile phone. All of them (except As The Worm Turns, which notes my brother gave to me!) were converted from a Google-gathered MIDI file using the excellent Ringtone Tools software. Why?! Just because I like these melodies; and because I think they are pretty distinctive ringtones!

P.S. - and yes, I didn't respected the tempo, for several reasons!

Diamond Rio PMP300 FS-plugin

Sat, 06 May 2006 00:26:38 -0300

Diamond Rio PMP300, with only 32 MB of flash memory, was the second portable MP3 player ever released, in 1998. Unfortunately, such a revolutionary piece of hardware is very painful to interface with: as it is connected through parallel port, highest transfer rates achieved were around 80 KB/s. And the software bundled with it was too primitive. To the luck of thousands of (un)happy Rio owners, The Snowblind Alliance released their Open-Source RIO utility, which became a starting point of several alternative Rio manager interfaces. Mine is just one of them
First of all, there's absolutely no need to write the entire file manager. Total Commander (TC for short) is one of the most feature-rich file managers ever made, and it supports a very extensible plugin API. As a result, one could use TC to manage files directly on the flash memory of his/her Rio! Actually, my plugin supports listing, uploading, downloading & deleting files from Diamond Rio PMP300 internal memory. It also displays the transfer speed and the total/remaining space. Take a look at this screenshot to see it in action. Behind the GUI, my plugin uses the source of the "RIO utility v1.07" by The Snowblind Alliance.

Installation:

Just the same as for many other FS-plugins:

Unzip rio.wfx & rio.cfg files to Total Commander directory
Choose "Configuration => Options => Operation => FS-Plugins"
Choose rio.wfx
Click OK.
You can now access the plugin in the "Network Neighborhood"
Open rio.cfg file and set the correct LPT port address (see below for more details)

Please note that DriverLINX Port I/O Driver by Scientific Software Tools, Inc. is required for plugin to operate. Get it below.

Configuration:

In the majority of cases, the plugin may work fine "out-of-the-box". If it doesn't work at all, probably you'll need to discover and specify your PC's parallel port hardware address. Open your system's "Device Manager" (on Windows XP, open the context menu for "My Computer", click "Properties", go to the "Hardware" tab, and click the "Device Manager"). Go straight to "Ports (COM & LPT)". Now locate the port that your Rio device is attached. On my case, it's LPT1. Double-click "Printer port (LPT1)", and go to the "Resources" tab. You need the first one of "I/O Range" numbers:

378 is what you need. Note that this number is in a hexadecimal format. Thus, many programs (like my plugin) may accept it as 0x378. Now, open the rio.cfg file. It looks like this, by default:

# Assume that Rio is connected to LPT1
IOPort		0x378

# default
IODelayInit	20000
IODelayTx	100
IODelayRx	2

# "turbo" mode (UNSAFE!!!)
#IODelayInit	5000
#IODelayTx	1
#IODelayRx	1

Now, just update the IOPort parameter to the value you discovered.
Note all that IODelay* parameters. For the safety reasons, the delays are high by default, and, consequently, the file transfer is slow. If you comment out the default values and uncomment the turbo mode ones, you'll get a great increase in performance! But remember to only use it when your Rio battery is 100% charged, and when your Rio is turned on. It may corrupt some bits, through.

rockin' PC speaker

Thu, 20 Apr 2006 02:06:04 -0300

Well, good old PC speaker is the only default hardware, easily available on almost all PC systems, and virtually unmuteable (actually, one can connect PC speaker output to his/her sound card instead of default buzzer, but this rarely happens . Thus, it is perfect for communicating critical states. But the default system beep is quite boring, and makes difficult to distinguish different events that are being communicated. So, here's my humble attempt to make a highly portable function that is able to play simple non-polyphonic music on the PC speaker. I used it originally to advise when someone tried to log in to my system through SSH daemon (thus the name "daemoniac" - demoniac . It was tested (and worked fine!) under:

DOS (DJGPP, Turbo C)
Windows 9x/NT/2K/XP (Borland C, Microsoft Visual C, MinGW)
Linux (gcc)
FreeBSD (gcc)

By default, demoniac will play Iron Maiden - Fear Of The Dark beginning. You can also compile it to play the simple "A#4 D#5 G5 A#5 G5 A#5" melody. Note that on UN*X systems, demoniac accesses hardware directly, and thus requires to run as root user. It's safe, through: it won't accept any command line arguments and neither process environment variables, so, at least, it can't be exploited with some buffer overflow technique. For detailed instructions about compiling demoniac on different compilers/systems, read the comments at the start of the source. Note that my package provides all the binaries generated on compilers/systems listed above.

	REQUEST	RESPONSE
SSL size:
Min header length:
Max header length: