The DMZ

Mark Buffalo

01:11

man. bootstrap is a waste of time and effort

responsive design is not hard...

why throw in 300KB of CSS and Javascript when I can just do this myself much quicker :/

AviD

07:18

@RоryMcCune dont remember who it was, but somebody tweeted "Just saw Van Wilder 3, and it was great!"

also, I knew she was cool, but never knew she was such a pottymouth.

TildalWave

07:45

Is it amateur day already?

@AviD Can you show some source that shows 3DES is not secure? Or not better then DES? (For compatibility reasons it is rather important for us to use 3DES instead of AES) — user200312 1 min ago

some pass me a mallet please

AviD

right??

@MarkBuffalo but why not? KBs are cheap!

@MarkBuffalo hahahaha just saw your message....

my condolences

TildalWave

@AviD Can you show some source that shows 3DES is not secure? Or not better then DES? (For compatibility reasons it is rather important for us to use 3DES instead of AES) — user200312 5 mins ago

AviD

@TildalWave I am tempted to close it as clueless

TildalWave

welcome to fkin 40 years ago

AviD

actually though it is not a SO question, but maybe a crypto.se

TildalWave

07:51

the question is where will he/she be a subject of ridicule the most ... then migrate there

this is a class example

dev logic: it works, therefore it is secure

I fkin hate devs, and I am one (kinda)

AviD

@TildalWave then here

Arperum

Wait? @TildalWave didn't you used to be a mod? Or am I confusing you?

AviD

Crypto.se will approach it as a theoretical question

SO will tell him it's okay

actually, SO would probably tell him not to bother with 3DES, plain DES is just fine

TildalWave

@Arperum had to quit for mental health reasons :)

AviD

@Arperum @TildalWave oh! you lost your blue!

@TildalWave heard that

can totally understand

Arperum

07:53

@TildalWave Ah, so I was not misremembering.

AviD

No no no, do NOT do this yourself. Cryptography is delicate, there is many maths involved. If you don't know what you're doing, you will mess it up. And, if you are trying to implement 3DES out of DES in 2016, you definitely don't know what you're doing. — AviD ♦ 1 min ago

@AviD Can you show official source which says 3DES should not be used in 2016??? — user200312 1 min ago

@TildalWave can you give him a source for that? The wikipedia page is ambiguous.

AviD

08:27

@RоryMcCune

MARVEL'S DAREDEVIL Season 2 Trailer #2 (2016) Charlie Cox, Jon Bernthal Netflix HD

►

@RоryMcCune !!

TildalWave

@AviD soz, I stopped being interested with "it works, I'm fine with that"

AviD

yeah, he basically already made up his mind.

saw my base64+reverse comment?

TildalWave

I did now

wanna bet he's gonna use fixed keys?

"it works"

4

A: 3DES with fixed-encoded random key

The security of this scheme largely depends on how good your key generation is. If an attacker observes two key exchanges, he may calculate the xor of the two unobfuscated keys: The values ka and kb are two unobfuscated keys. kA and kB are the associated obfuscated keys. o is the static obfuscat...

kalina

good grief I hate children

Rory Alsop

@kalina set fire to them

kalina

08:33

@AviD " there is many maths involved "

AviD

@kalina so do I, especially the kind that pretend to be adults.

kalina

@AviD what are you trying to say

@RoryAlsop I don't have the energy to invoke fire, I got woken up by being JUMPED ON

AviD

@kalina magik faerie dust on the tip of a unicorn's horn

@kalina isnt that a good thing?

Rory Alsop

@kalina even when it's your own kids, that's not great

@AviD lol

kalina

@AviD context :(

AviD

08:34

@RoryAlsop I like when they wake me up that way

Rory Alsop

@AviD jumping, not so good. Cuddling, much better

AviD

its when they wake me up by kicking me in the face, or sitting on my head, that I dont like as much.

Rory Alsop

actually - depends on how heavy they are

TildalWave

@RоryMcCune Are session keys necessary, or using fixed keys is also OK? with 3DES — user200312 7 mins ago

boom!

knew it

AviD

@RoryAlsop oh absoultley. I'm talking about the small ones.

Rory Alsop

08:36

@AviD should we not migrate to Crypto? ;-P

Rоry McCune

@RoryAlsop we should

he wants to know how to implement 3DES

TildalWave

noooo

Rory Alsop

done!!!

(heh)

Rоry McCune

@TildalWave well he does

TildalWave

problem is not crypto it's the scheme

Rоry McCune

08:37

@TildalWave pls that's the kind of thing crypto like talking about

it's not "is this secure" it's "I want to implement 3DES myself, how do I do that"

AviD

@RoryAlsop I was considering

TildalWave

@RоryMcCune if you have to ask...

AviD

but @TildalWave said it should go where he will get mocked the most, I think we do that best.

TildalWave

exactly

Rory Alsop

@AviD you don't think there are crypto mockers?

Rоry McCune

08:39

@TildalWave oh I agree absolutely, but now several people have said that and he appears undettered

so he might as well get some advice on how to make less of a mess of it than he would otherwise

@AviD if we're lucky Tom Leek will answer

AviD

@RoryAlsop oh sure. But they would answer the theoretical question of "how to do this", and not "I want to actually build a system in 2016"

@RоryMcCune ooh yeah

ping him

Rоry McCune

@AviD are you suggesting our crypto bretheren aren't concerned with practicalities

TildalWave

or maybe DW

AviD

@RоryMcCune not at all

dammit chris!

@user200312 3DES is still pretty secure: the best known cryptanalysis (on keying schedule 1 or 2) takes about 2^112 operations to crack. And 3DES is what is used by the credit industry in transaction requests by EMV cards, so take that as you will. — Chris 36 mins ago

kalina

he has a different opinion to you and called you out on it in public

you should nuke him

AviD

08:44

pffft

kalina

I'm serious, your entire reputation hangs in the balance

obviously the balance is counterbalanced by air, such is your reputation

CodesInChaos

@AviD Time for another anti OSI crusade:

7

Q: What do TCP/UDP add to "raw ip"?

I know that both TCP and UDP are built on top of IP, and I know the differences between TCP & UDP, but I'm confused about what exactly "raw ip" is. Would it be fair to say that TCP & UDP both implement IP, but that IP in and of itself isn't capable of transferring data? Or is IP some very low lev...

ip

AviD

@kalina aww sweet

@CodesInChaos heh nah, I'm tired of that one

Rоry McCune

great news @AviD your favourite language just got a new release!

blog.jetbrains.com/kotlin/2016/02/…

AviD

@CodesInChaos also JEEZUS on network engineering???

@RоryMcCune what's that? some kind of hip video streaming website?

CodesInChaos

08:46

In the ANSWERS

kalina

@RоryMcCune PHP 6?

Rоry McCune

@kalina pls, @AviD is waaay too hipster for PHP, thus his love of a combination of Kotlin and 4GLs

TildalWave

@user200312 Please see 3DES with fixed-encoded random key. You might be "OK with it" because "it works", but your users might not be and they deserve someone that knows what they're doing. I just hope I'm not one of them. — TildalWave 17 secs ago

AviD

@CodesInChaos actually only one answer, and not the top one. The top one mentions it for additional reading, for understanding the concept of layers - WHICH IS EXACTLY THE POINT

kalina

@RоryMcCune I wish I knew what you were talking about

wait a minute, no I don't

Rory Alsop

08:53

@kalina (words. hipster stuff.)

Rоry McCune

@RoryAlsop only you could call 4GLs hipster :op

Rory Alsop

@RоryMcCune lol

kalina

that look on your face when somebody sits down next to you with a surface 3 or 2

and you're just like =D

take a look at the new touch cover

look at this screen

Rоry McCune

"Though used earlier in papers and discussions, the term 4GL was first used formally by James Martin in his 1982 book Applications Development Without Programmers"

kalina

poor you

Rоry McCune

08:54

@kalina SP4-Master-Race!

kalina

oh you have a surface 2! that's so adorable, look how tiny it is

Rory Alsop

@kalina hahahaha - sizeist

kalina

oh don't mind me, I'm just playing civ 5 on my surface pro four.

"it's the motion in the ocean" vs "who really wants to travel to hawaii on a row boat?"

Rory Alsop

@kalina Thor Heyerdahl?

kalina

bla bla bla and some people did the smaller end of the scale as well

that doesn't make it right

Rory Alsop

08:57

lol

I know

kalina

also, LYNE is amazing for passing hours of my life

TildalWave

@kalina OK, but can it make toast?

kalina

@TildalWave who needs a tablet that makes toast

TildalWave

I do :P

kalina

it keeps my hands toasty if I hold it right

top right corner

Lighty

08:59

@kalina All hail Ghandi

kalina

@Lighty pls ghandi has double unhappiness from # of cities

he's great if you're going for a four city cultural victory but once I get to the atomic era I want to nuke everybody

Google Chrome is such a power whore as well

I had to uninstall it

it was responsible for 40% of my battery usage during sleep

Lighty

@kalina Was referring to a very old bug/meme/whatever, but ok, I play as the dutch anyways because go netherlands

Now I'm curious, what does @kalina think of that new Civ game in space? :P

kalina

@Lighty pls rome because faster building production if building exists in capital

TildalWave

@kalina ooo look who's complaining about Chrome hogging up your cool

kalina

@Lighty not as good as civ 5

@TildalWave pls I use edge

TildalWave

09:02

IIRC you had things to say when I moved to Firefox from Chrome for similar reasons

kalina

I have things to say about everything

Lighty

@kalina finally something we can agree on, I like it, but it feels so watered down, since Civ 5 felt much larger and better xd

TildalWave

:)

CodesInChaos

@AviD Two answers talk about Layer 3/4. Numbering layers makes no sense.

kalina

@Lighty what do you mean finally

Rory Alsop

09:04

@CodesInChaos exactly! Literally no actual real world apps use the OSI model.

They are all roughly around about a bit like parts of OSI

Lighty

@kalina shrugs If you literally translate "Finally something we can agree on" to dutch, then it becomes a Metaphor like thing over here, so I thought you English speaking beings had something similar to it too

CodesInChaos

I dislike OSI even as a concept.

kalina

"Literally no actual real world apps use the open source initiative model"

is that what that sentence says?

CodesInChaos

Anything above IP can be replaced, split or reordered at will.

Rory Alsop

@kalina Open Systems Interconnection

CodesInChaos

09:06

OSI model

The Open Systems Interconnection model (OSI model) is a conceptual model that characterizes and standardizes the communication functions of a telecommunication or computing system without regard to their underlying internal structure and technology. Its goal is the interoperability of diverse communication systems with standard protocols. The model partitions a communication system into abstraction layers. The original version of the model defined seven layers. A layer serves the layer above it and is served by the layer below it. For example, a layer that provides error-free communications across...

Rory Alsop

@CodesInChaos yup

kalina

don't make me fulfil @Simon's role of calling you all nurds

Rory Alsop

@kalina don't fill @Simon's anything pls

AviD

@CodesInChaos sure it does, you can number it sequentially.

kalina

well I'm sure @Simon would do the filling

he would be right up here calling you all nurds

is still early you can't talk so much nurd

CodesInChaos

09:07

@AviD But for that to make sense you need a fixed ordering.

AviD

up until TCP it makes sense, and is almost-but-not-quite de facto standard. Above that it makes sense as a relative notation, not absolute.

kalina

sense:absolute;

CodesInChaos

@AviD IMO even TCP doesn't make sense anymore.

kalina

right so that's four, just three more

CodesInChaos

TCP does four things at the same time.

AviD

09:09

@CodesInChaos oh?

@CodesInChaos okay...?

CodesInChaos

1) The port field, so you can have several services on the same machine. 2) It forms a connection 3) It does flow control 4) It does reliability

AviD

sure. so?

its not different layers?

CodesInChaos

IMO all of these deserve a separate layer that can be swapped individually

and 2-3 mean it clearly includes higher layers than UDP, so putting it at the same layer doesn't make much sense.

AviD

@CodesInChaos 1 and 2 need to go together. 3 and 4, while seperate, still make sense together. Moreover, putting 3 and 4 as aspects of the connection (#2) makes sense too.

@CodesInChaos well thats the difference between TCP and UDP.

I actually had to explain that difference this week, to my high school class.

I did have to simplify it a lot ... :-(

the spirit of Tim BernersLee is turning over in its grave.

YES I KNOW

CodesInChaos

But if, for example I want to replace the connection level, to add connection level crypto, fusing all those layers in one protocol prevents that.

Or I want to swap the flow control for LEDBAT or whatever fits my application.

AviD

09:14

@CodesInChaos huh dunno wat ledbat

@CodesInChaos I dont see it.

CodesInChaos

@AviD flow control that torrent uses (on top of UDP) to reduce disturbances of other connections.

AviD

the way I see it, you have 3 choices: 1) you want the connection, and everything that implies; 2) you DON'T want the connection, and everything THAT implies. 3) you want to do something custom and non-standard.

@CodesInChaos yeah reading

CodesInChaos

@AviD For example I don't like the connection feature of TCP because it sucks (No crypto, vulnerable to RST attacks, etc). So I swap in another protocol that's better, but reuse the flow control and reliability layer of TCP.

AviD

> and is used by Apple for software updates

@CodesInChaos but what you are saying would lead to splintering. IMO there is much value in having a few standard choices.

the standard protocol sucks? improve it.

dont split it out to 13 similar, yet ultimately different, protocols.

CodesInChaos

Bernstein's CurveCP comes closest to what I want, but it suffers from the typical Bernsteinisms.

AviD

09:18

@CodesInChaos whooosh

heh your blog is #5 for that term.

CodesInChaos

It's UDP->Crypto+Connenction->Flow Control->Reliability

AviD

but but but! UDP is connectionLESS

CodesInChaos

@AviD You build the connection on top of UDP.

AviD

@CodesInChaos what are typical Bernsteinisms?

@CodesInChaos again, why dont you just fix TCP?

CodesInChaos

@AviD Increasing the modularity of TCP is the most important fix TCP needs.

AviD

09:22

hmm good point.

CodesInChaos

@AviD Half finished code. Extremely unusual code structure. A rule the world philosophy.

AviD

kinda like how SSL as a protocol supports plugging in different ciphers.

TildalWave

@CodesInChaos one key to rule them all?

CodesInChaos

I'd like flow control layers and reliability layers as simple libraries that can be used from user-mode.

AviD

@CodesInChaos oh no that I would NOT like at all.

because programmers are gonna go and mess up the hell out of that.

CodesInChaos

09:24

@TildalWave No, it expects to have one crypto-termination service at the OS level. And then expects applications to communicate with that via pipes/file-descriptors.

AviD

at least now, there is very little they can do wrong at those layers, and they confine their fuckery to the higher levels.

TildalWave

@CodesInChaos not sure that's not even worse :O

AviD

@CodesInChaos so he's brilliant at pure mathematical crypto, and sucks at the real world implementation?

CodesInChaos

@AviD The implementation is also brilliant. But only if you have the freedom to reinvent your whole software and OS stack at the same time.

And you buy into his rather unconventional style.

AviD

@CodesInChaos hmm, maybe a better word for what I meant would have been deployment.

as in, not the code writing, but the using.

UX and etc.

CodesInChaos

09:28

Yeah. He sucks at finding a path from the current messy world to what he imagines as ideal world.

AviD

the problem is, even in an ideal world, you still have messy humans to deal with.

kalina

is IIS susceptible to Heartbleed?

AviD

and messy applications written by messy programmers.

@kalina no

CodesInChaos

@kalina No. It uses MS's crypto lib (SChannel), not OpenSSL.

AviD

heartbleed is OpenSSL only. IIS does not use that.

unless your app uses it, e.g. in PHP.

CodesInChaos

09:30

Or you use a reverse proxy/SSL terminator in front of IIS.

kalina

you know quick answers like that is basically the reason I idle in here

AviD

@CodesInChaos sure, but then its not on IIS...

@kalina heh

CodesInChaos

Some of Bernstein's colleagues build an OS (EthOS) that fits with DJB's ideal model.

AviD

I always assumed it was the simonmocking and roryworship.

@CodesInChaos I'm sure the UX is fantastic.

Rory Alsop

@AviD :-)

AviD

10:08

@RoryAlsop how do you ping a site's mods in TL?

that DES-ECB bloke asked on SO...

-10

Q: Implementing 3DES using DES

I have existing class which performs the DES computation. Can I implement 3DES from this class, if yes how? Also what are best practice to use 3DES? Keys, encryption mode, etc. PS. Is it possible to use 3DES for MAC? PPS. Currently I have such algorithm for MAC HMAC := DES(block1 xor block2 ...

c++ c des

actually getting decent responses, at least in the comments.

Arperum

I understand but current one works like this and I think it will give some "reasonable" security, I don't want security against NASA — user200312 3 hours ago

Amazing. I think NASA has other things to do than hack stuff, they'll leave that to the NSA.

TildalWave

@AviD [site] mods: [message]

AviD

@TildalWave ah cheers

Lighty

10:26

The moment you use XKCD comics in confidential papers to explain stuff and get bonus points from boss for being clear with explanation

Thomas Pornin

@AviD 3DES is still "approved" by NIST as long as it is the three-key variant (see NIST SP 800-131A rev 1).

AviD

@ThomasPornin yeah I know

but he wants to use the 2key variant

with fixed keys

oh yeah, and ECB

Thomas Pornin

@AviD But that's not the worst part of his custom MAC scheme.

0

A: Implement 3des using des

Calling "HMAC" that which is not (at all) HMAC can only lead to confusion. Though DES is, by today's standards, too weak for comfortable usage, this is not the weakest part of your custom MAC. In fact trouble begins right at the XORing of the blocks together. For instance, the attacker may swap ...

AviD

and still and besides, even so, I would not consider 3DES to be a wise choice, even when used properly.

@ThomasPornin oh yeah didnt even get to his mac

woot a bear answer!

and one I totally understand too.. about crypto :-O

> This is a bit like driving a 40-ton truck: being extra careful is not sufficient not to run into trouble; you really need to first learn how to drive.

and another classic bearism.

@ThomasPornin (in your notations, that K1 and K3 may be distinct from each other) -> surely you mean "MUST" be distinct?

and yet and even so, telling him to implement new code with 2016 is still not a good idea.

you're right though that its not the worst part of his scheme, but still.

Thomas Pornin

@AviD No, it is still a "may". In the three-key variant, the three keys are supposed to be chosen uniformly and independently of each other, which means that they are still allowed to be equal out of pure chance.

AviD

10:35

okay, then at least should.

actually you said "distinct", not "unequal". So semantically, you do mean "must".

Thomas Pornin

If you say "MUST be distinct" then people will begin to do something weird like actually checking that they differ, or force some bits to specific value to ensure that they are distinct.

AviD

the more we engage with this user, the more I think all these answers are wrong: the correct answer is simply "step away from the keyboard before you hurt somebody".

Telling a 5 year old the correct way to hold an electric saw is not optimal.

(shuddup @RoryAlsop I mean normal 5 year olds, not your uber scotson. )

Thomas Pornin

If you assume that flipping bits won't go undetected then you basically assume that the MAC is useless. Then why bother ? As for ECB mode, it is intrinsically weak. Using K1==K3 is the "two-key" 3DES variant that NIST explicitly disallows. As for the overall security of your scheme, my overall professional assessment is that it totally stinks. — Thomas Pornin 1 min ago

AviD

nice "professional assessment". :-)

Rory Alsop

10:51

@AviD hahahaha - admit it, you do the same with your kids.

AviD

heh I wish

not the saw, but other tools

I do get them to at least be comfortable with e.g. screwdriver, hammer, etc...

Rory Alsop

fair enough - we don't actually have any electric saws at the moment. I do want a decent table band saw though... and they will want to use it :-/

AviD

but my kids are more brainy than physical, so even that is not natural

Rory Alsop

brainy can be aligned with physically creative

Rоry McCune

ahh sqlmap what a great time saver

I would not want to exploit blind boolean SQLi without it!

AviD

10:56

@RoryAlsop yeah but they aint

buncha lazy potatoes

Rory Alsop

pfffft

reminds me of that joke "I am in shape. It's just that the shape is... a potato"

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