I've stumbled on Dan Boneh Number Theory Cheat sheets. Number 1 and Number 2. Quick to read, I'm going to print them and display them somewhere on my walls :)
I also ran into the homepage of Vitaly Shmatikov. He uploaded a lot of slides, presentations and resources on a lot of different courses related to security and cryptography. He also lists a lot of interesting papers. I want to read everything but right now I have to focus on my exams (and interviews for my internship...).
EDIT: Oh but one last link. Orange Labs publications. There are some interesting papers in there too. I'm mostly writing this post to bookmark all those great links somewhere.
EDIT2: How to do a litterature search. That might be useful.
EDIT3: I have also returned to the Rss readers that I had banished from my life something like 7 years ago. I have a tendency to get addicted to things pretty quickly and back then I had subscribed to way too many feeds (I think one post would pop every 2 minutes) and I was constantly reading something. But I figured, what if I filled it with all those blogs on cryptography/security. That would be working and not slacking. So that's what I did. I'm using Digg on desktop and Feedly on my cellphone. And of course I'll be posting here the articles I find interesting :)
In one of my class the teacher advise against /dev/urandom.
I wondered why. I remembered reading some articles about random vs urandom and urandom being better, but that was years ago and my memory is not fresh. Wikipedia does advise against it, as does the manpage if you want to generate a long term key.
I also stumbled on one of Thomas Pornin's answer on the security SO also pointing to a blogpost from Thomas Hühn
tl;dr:
Fact: /dev/urandom is the preferred source of cryptographic randomness on UNIX-like systems.
I wrote about Differential Power Analysis (DPA) but haven't said that there were way more efficient attacks (although that might be more costy to setup). Differential Fault Analysis is a kind of differential cryptanalysis: you analyse the difference between blocks of the internal state and try to extract a subkey or a key. Here we do a fault injection on the internal state of the smartcard during an encryption operation (usually with lasers (photons have the property of igniting a curant in a circuit), or by quickly changing the temperature).
The attack presented in http://eprint.iacr.org/2010/440.pdf and https://eprint.iacr.org/2003/010.pdf is targeting the last subkey.
We inject a fault on 1 byte of AES (in the picture we consider the internal state of AES to be a 4x4 matrix of bytes) at a particular spot (before the last round) and we see that at one point it creates a diagonal of errors. We can XOR the internal state without fault with the faulty one to display only the propagation of the fault.
Here, by doing an hypothesis on keys and seeing how the Addkey operation is modifying this difference we can compute the last subkey.
On AES-128, it is sufficient to know K10 to find the cipher key, but on AES-256, you must know K13 and K14
Although this is only my understanding of the DFA. It also seems to be easier to produce on RSA (and it was originally found by Shamir on RSA).
I'm studying the internals of hash functions and MACs right now. One-way Compression Functions, Sponge functions, CBC-MAC and... the Merkle–Damgård construction. Trying to find a youtube video about it I run into... The Cryptography course of Dan Boneh I already took 3 years ago. I have a feeling I will forever return to that course during my career as a cryptographer.
The whole playlist is here on youtube and since his course is awesome I just watched again the whole part about MACs. And I thought I should post this explanation of the birthday paradox since as he says:
Everybody should see a proof of the birthday paradox at least once in their life
Something that always bugged me though is that he says the formula for the birthday is 1.2 sqrt(365) whereas it should be square root of 366 since there are indeed 366 different birthdays possible.
This morning I had a course on Return Oriented Programming given by Jonathan Salwan, a classmate of mine also famous inventor of RopGadget.
The slides are here.
A lot of interesting things there. Apparently it's still kind of impossible to completely protect your C code against that kind of attack. Even with all the ASLR, PIE, NX bit and other protections... There is also an awesome lecture about ROP on Coursera I linked to in the previous post here.
Basically, since you can't execute code in the stack, and since the addresses of libraries are randomized because of ASLR, you can find bits of codes ending with a return (called gadgets) and chain them since you control the stack (thus the saved EIPs). What I learned by doing was that it gets complicated if it's 64bits (since a lot of address will have a lot of 0x00 and you can't point to those doing a buffer overflow through a strcpy or something similar) and you won't get a lot of those gadgets if you have dynamically loaded libraries. Static libraries are loaded in the .text section (which is executable of course), so that's all good. Also a good way to store strings of data are in the .data section since it is untouched by the randomization contrarily to the stack.
A lot of researches is done on the subject and new tools like RopGadget are coming, using an old concept (but still actively researched): the SAT solvers. There seems to be a problem though, those SAT solvers yield a set of gadgets to be used for some action you want to accomplish with your shellcode, but you have to do the work of putting them in the right order.
This is what I took from that talk, you can question the guy if that interests you!
I've already talked about Coursera before, and how much I liked it.
The Cryptography course by Dan Boneh is amazing and I often come back to it when I need a reminder. For example, even today I rewatched his video on AES because I was studying Differential Fault Analysis on AES (which is changing bits of the state during one round of AES to leak information about the last round subkey).
So if I could give you another course recommendation, it would be Software Security by Michael Hicks. It looks ultra complete and the few videos I've watched (to complete the security course I'm taking at the University of Bordeaux by Emmanuel Fleury) are top notch.
Communication Theory of Secrecy Systems is a paper published in 1949 by Claude Shannon discussing cryptography from the viewpoint of information theory. It is one of the foundational treatments (arguably the foundational treatment) of modern cryptography. It is also a proof that all theoretically unbreakable ciphers must have the same requirements as the one-time pad.
source: wikipedia
I found an old Matthew Green's post where he wrote a really useful list of cryptography blogs and resources
I'll get back here after reading everything.
