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Everything you need to know about cryptography in 1 hour (2010) [pdf]

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Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#12
post #9
post #8

The reason this is being (re)posted now is that I gave this talk at a Polyglot Vancouver meetup last night. Freed from the constraint of a conference schedule I actually took about 90 minutes to go through this talk this time (followed by another 30 minutes of questions).

As someone who is completely new to cryptography and knows very little, where would you recommend I start? I've recently been reading about bitwise operations to become familiar with how to (somewhat) interpret what a cryptograhic algorithm is doing in a program, since bitwise operations seems to be popular in almost all crypto algorithms.

The free cryptography courses at Coursera. I have seen the videos uploaded somewhere, maybe you can find them.

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#13
post #9
post #8

The reason this is being (re)posted now is that I gave this talk at a Polyglot Vancouver meetup last night. Freed from the constraint of a conference schedule I actually took about 90 minutes to go through this talk this time (followed by another 30 minutes of questions).

As someone who is completely new to cryptography and knows very little, where would you recommend I start? I've recently been reading about bitwise operations to become familiar with how to (somewhat) interpret what a cryptograhic algorithm is doing in a program, since bitwise operations seems to be popular in almost all crypto algorithms.

I would highly recommend reading Cryptography Engineering [0] cover to cover. It's amazingly readable, covers the basics, the theory necessary to understand how things works and includes ample practical advice and observations on the industry.

The first thing I did after the Snowden leaks was read through the entire thing and after doing so I really wished I had done this years earlier. There's very few books that I think should be required reading across the board for software engineers, but this is one that I do think everyone writing code should read every page of.

[0] http://www.amazon.com/Cryptography-Engineering-Principles-Pr...

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#14
post #4

He recommends HMAC-SHA256 in this paper, but I think that AES-GCM is a better construction, as long as you understand the requirements for IV uniqueness. It offers significant improvements on top of the standard HMAC (privacy and additional out-of-band data) without adding much in terms of size.

"And I still maintain that recommendation. CTR+HMAC is far more robust against side channel attacks than any AE mode." -- https://twitter.com/cperciva/status/475360367191674881

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#15
post #10
post #4

He recommends HMAC-SHA256 in this paper, but I think that AES-GCM is a better construction, as long as you understand the requirements for IV uniqueness. It offers significant improvements on top of the standard HMAC (privacy and additional out-of-band data) without adding much in terms of size.

Would HMAC-SHA256 been a better recommendation in, the year that this presentation was given, 2010?

"Just reviewed my "crypto in 1 hour" talk slides in preparation for giving this talk on Wednesday. 4 years after writing, no updates needed." -- https://twitter.com/cperciva/status/475359526145646593

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#16

Would be interested in hearing more detail about your objections to both Poly1305 and ECC.

Too many ways to screw things up, not enough decades of cryptographic analysis, and there are simpler tools available which have been around for longer.

This is subject to the caveat that ECC offers benefits under certain specific conditions (e.g., you need small signatures or a small ASIC die area); but in those situations you want to talk to a cryptographer anyway. My talk was providing guidelines for software developers who are writing code for general-purpose PC hardware.

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#17
post #7
post #6

Here's a provocative gem: > The purpose of cryptography is to force the US government to torture you.

It's pretty simple -- if the US government really really wants your secrets, they can kidnap you and torture you until you tell them what they want to know. Cryptography can protect data, but it doesn't protect humans; all it can do is make sure that humans are the only remaining point of attack.

That's not entirely true.

Proper cryptography can keep them from learning that it's you they'll need to kidnap to get the secret, or even keep them from learning that there is a secret they might care about in the first place.

Also, there are plenty of bad guys in the world that can't kidnap and torture you that it's still quite worthwhile to keep your secrets from.

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#18
post #9
post #8

The reason this is being (re)posted now is that I gave this talk at a Polyglot Vancouver meetup last night. Freed from the constraint of a conference schedule I actually took about 90 minutes to go through this talk this time (followed by another 30 minutes of questions).

As someone who is completely new to cryptography and knows very little, where would you recommend I start? I've recently been reading about bitwise operations to become familiar with how to (somewhat) interpret what a cryptograhic algorithm is doing in a program, since bitwise operations seems to be popular in almost all crypto algorithms.

The Crypto 101 ebook [1] has been discussed a bit on HN [2]. It was submitted by tptacek, who had positive things to say about it.

It is in my "summer reading" pile.

[1] https://www.crypto101.io/

[2] https://news.ycombinator.com/item?id=7430946

Re: Everything you need to know about cryptography in 1 hour (2010) [pdf]

#20
post #8

The reason this is being (re)posted now is that I gave this talk at a Polyglot Vancouver meetup last night. Freed from the constraint of a conference schedule I actually took about 90 minutes to go through this talk this time (followed by another 30 minutes of questions).

Do you have a copy of the presentation in beamer's "handout" mode? I think that is what it is called. It is the mode that condenses the 140+ pages into 20-30 by collapsing all the reveals.
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