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The Bitcoin Piñata

ownme.ipredator.se

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Re: The Bitcoin Piñata

#51

Post by pqwy »

nothrabannosir wrote: post #41
gradinafrica wrote: post #37

They seem to assume the reader has a certain level of competency with web traffic monitoring and client/server communicating tools. I suppose this is half the fun. Still, I'm trying to figure out what they mean by > " Before you ask: yes, Piñata will talk to itself and you can enjoy watching it do so. " Also, what should I be using to connect using TLS/TCP?

They offer a TLS client and server interface, so you can have your own host act as a proxy. Try this: $ mkfifo /tmp/tlspipe $ nc -l -p 40001 /tmp/tlspipe Then visit http://ownme.ipredator.se:10001 from that same host (curl or firefox or whatever). Now look at /tmp/tlspipe. Disclaimer: I'm completely unfamiliar with named pipes or tls, but I think this is what they mean. EDIT: This should also work: $ mkfifo /tmp/tlsp…

Hah, and I wondered how come we suddenly started getting MITM connections from several places.

FWIW you can also do it with a single socat invocation, but I'll leave the exact command as an exercise for the reader.

Re: The Bitcoin Piñata

#52

Post by [deleted] »

philk10 wrote: post #35
MrRogers wrote: post #33

Where could I, a total beginner in crypto-stuff, learn more about this kind of thing? What would be the list of things I'd need to know how to do in order to "break in", and where could I learn how to do them?

One possible starting point is here - http://cryptopals.com

[deleted]

Re: The Bitcoin Piñata

#53

Post by pqwy »

ctz wrote: post #34
hannesm wrote: post #20

Earlier quoted context omitted.

This is about the DigestInfo -- which we generate and compare here: https://github.com/mirleft/ocaml-tls/blob/master/lib/handsha... The unpad does RSA unpadding... or am I completely mistaken?

I was reading the X509 certificate verification code, rather than the TLS code: https://github.com/mirleft/ocaml-x509/blob/master/lib/certif...

Why do you think this creates malleability?

PKCS1.5 stripping takes away the leading 0x00 0x01 0xff ... 0x00 -- if this prefix is not present, it fails.

The rest goes through the RSA tranform, and is parsed as PKCS1 DigestInfo, an ASN.1 structure. All ASN parsing checks for presence of trailing bytes, on top and in CONSTRUCTED nodes.

The presence of suffix-checking prevents malleability in my mind. Am I missing something?

Re: The Bitcoin Piñata

#54

Post by kzrdude »

mintplant wrote: post #16
amirmc wrote: post #15

Earlier quoted context omitted.

> "Break in and take it." But please tell us if you do. We'd like to learn from this exercise and improve the stack.

If you're not already, it'd be a good idea to log all traffic to/from the box so that you'll at least have something if no one owns up.

Ah, but it's so ironic if ipredator.se does that.

Re: The Bitcoin Piñata

#55

Post by runeks »

avsm wrote: post #14
econner wrote: post #12

FYI The bounty is about $2000.

As Bruce Schneier pointed out [1], the price is definitely not meant to be a massive incentive -- any cryptographer worth their salt is going to be worth a hell of a lot more than our prize amount. But at the same time, we're really keen to make it easier to audit protocols in MirageOS, and hope that this Piñata "permitted breakin" is something that'll catch on. The worst case for us is that someone does break in and…

> The worst case for us is that someone does break in and doesn't tell us how they did it.

I do hope you're logging all incoming data to a backup server somewhere, so you can analyze it afterwards if this were to happen.

Re: The Bitcoin Piñata

#58

Post by posnet »

nothrabannosir wrote: post #41
gradinafrica wrote: post #37

They seem to assume the reader has a certain level of competency with web traffic monitoring and client/server communicating tools. I suppose this is half the fun. Still, I'm trying to figure out what they mean by > " Before you ask: yes, Piñata will talk to itself and you can enjoy watching it do so. " Also, what should I be using to connect using TLS/TCP?

They offer a TLS client and server interface, so you can have your own host act as a proxy. Try this: $ mkfifo /tmp/tlspipe $ nc -l -p 40001 /tmp/tlspipe Then visit http://ownme.ipredator.se:10001 from that same host (curl or firefox or whatever). Now look at /tmp/tlspipe. Disclaimer: I'm completely unfamiliar with named pipes or tls, but I think this is what they mean. EDIT: This should also work: $ mkfifo /tmp/tlsp…

For those who are interested, this is a great source of cool things you can do with netcat.

http://www.felipemartins.info/2013/03/netcat-the-it-swiss-kn...

Re: The Bitcoin Piñata

#59

Post by StavrosK »

amirmc wrote: post #10
Tuna-Fish wrote: post #9

Earlier quoted context omitted.

Even less technical: A bunch of people write crypto software, and want to find out/demonstrate how secure it is. They do so by setting up a system that will transfer ~$2k worth of bitcoins to the first guy who breaks it.

> "and want to find out/demonstrate how secure it is" As the page (and my post) emphatically state, this contest cannot prove anything about how secure it is. That distinction is really important.

But it can demonstrate how insecure it is!

Re: The Bitcoin Piñata

#60

Post by amirmc »

joshu wrote: post #40

The other interesting bit is that if you really want to chip in you could send bitcoin TO that address to sweeten the pot.

I bet the authors never considered that as part of their threat models.
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