Fantastic lectures, professor Paar! Just want to thank you for the excellent effort you put into these! What you say at 55:00 is something all lecturers need to strive for!
Thank you! This series was instrumental in helping me pass my cryptography module at KCL. I'd read their stuff and come here to have it make sense. Then I went back and just made sure I knew their notation for the algorithms.
This was the most informative and clear lecture of the series so far (going through in order). Professor Paar's accent and cadence are particularly engaging (he should consider radio or film if lecturing get too booooring (said in the Paar style/cadence/idiom) for him).
Unfortunately there is a little mistake in the last formula for computing W_j: After XORing the four previously computed Ws one has to do a rotation to the left by one bit.
Thanks again for all this great stuff. I would like to know where i could find explanation about the WHY (why we use those 4 constants why we use those 4 functions and why we shift the message like that). I imagine that there is a Mathematical reasoning behind those choices and i would really be interested to understand them. Thanks !!!
Prashant Dhumal its secure for using in cryptographic uses like finger print and using in digital signature algorithms and ... . it has 4 requirements professor Paar mentioned in lecture 20. there are other hash functions which are not secure and doesn't have those requirements.
I know this is 2 years later but the reason is that information gets lost. You AND two bits A and B, and you get a 0 you only know that A and B were not both 1, but you don't know if A was 0 or B was 0 or both were 0. This makes it hard to reverse engineer
+Saurabh Parekh Unfortunately not. However, SHA-512 is not that different from SHA-1. Once you understood SHA-1, SHA-512 shouldn't too difficult. (Note that SHA-3 is completely different from SHA-1 und -2). Cheers, christof
Now, coming to SHA-3, do you plan to offer a video lecture on it please? It is quite convoluted and all I am seeing is the push for its adoption for most of the future hash designs...
Fantastic lectures, professor Paar! Just want to thank you for the excellent effort you put into these! What you say at 55:00 is something all lecturers need to strive for!
Thank you! This series was instrumental in helping me pass my cryptography module at KCL. I'd read their stuff and come here to have it make sense. Then I went back and just made sure I knew their notation for the algorithms.
19:00 SHA-1
Correct me if I'm wrong but this is actually SHA-0. SHA-1 requires a circular shift to the left by 1 position of the "words", Wj (16
the best observation, the teacher was in a hurry xD
I wish I had read your comment earlier, I tried to reprogram this algorithm on my own, but I didnt work until I found this tiny mistake...
Even I was confused with this, Thanks a lot
This was the most informative and clear lecture of the series so far (going through in order). Professor Paar's accent and cadence are particularly engaging (he should consider radio or film if lecturing get too booooring (said in the Paar style/cadence/idiom) for him).
SHA1: algorithm 21:40 (high level)
SHA1: rounds details 52:30
SHA1: word scheduler 1:11:57
Best cryptography lectures :)
Thanks Professor .Does Sha1 specifies anything about IV (ie : h0 to be used when compressing x1 ) ?
Thank you so much sir and your videos are really helpful thank you..!!
It is really enjoyable to watch it
Unfortunately there is a little mistake in the last formula for computing W_j: After XORing the four previously computed Ws one has to do a rotation to the left by one bit.
Thanks again for all this great stuff.
I would like to know where i could find explanation about the WHY (why we use those 4 constants why we use those 4 functions and why we shift the message like that). I imagine that there is a Mathematical reasoning behind those choices and i would really be interested to understand them. Thanks !!!
Vielen Dank! Grüße aus Karlsruhe!
it's funny when you watch it online. what delay? you're right on my schedule. :D
SHA-1 is now dead but this lecture is still valuable for learning purpose
2 years later, SHA-1 follows alive
Any programming explanation of these lessons. Or any resources to learn programming for these lecture. Any helps
Which software or tool.to analyze this collision, any could name it
Hi
Does SHA means secure hash ? if yes then where is the security comes from since we do not have secret value while generating SHA-1 hash
Prashant Dhumal
its secure for using in cryptographic uses like finger print and using in digital signature algorithms and ... . it has 4 requirements professor Paar mentioned in lecture 20. there are other hash functions which are not secure and doesn't have those requirements.
'Heres a .vbs to start your sha-1 hash dictionary
'records input word and output sha-1 hash ie. Cryptography, b804ec5a0d83d19d8db908572f51196505d09f98
'thanks to the prof for making these videos public.
Option Explicit
Dim asc, enc, bytes, instr, outstr, pos, FS, FT
Const ForReading = 1, ForWriting = 2, ForAppending = 8
instr = Inputbox("Enter string to encrypt with SHA-1:","")
Set asc = CreateObject("System.Text.UTF8Encoding")
Set enc = CreateObject("System.Security.Cryptography.SHA1CryptoServiceProvider")
bytes = asc.GetBytes_4(instr)
bytes = enc.ComputeHash_2((bytes))
outstr = ""
Set FS = CreateObject("Scripting.FileSystemObject")
Set FT = FS.OpenTextFile("sha1.txt", ForAppending, True)
For pos = 1 To Lenb(bytes)
outstr = outstr & LCase(Right("0" & Hex(Ascb(Midb(bytes, pos, 1))), 2))
Next
FT.WriteLine(instr & "," & outstr)
FT.Close
WScript.Echo instr & "," & outstr & vbcrlf & "added to sha1.txt"
WScript.quit
whatever you say nerd
The door was closed...
Nice
haha 3 years after the lecture, Google found the first SHA-1 collision
We know everything why it is difficult to reverse engineering ( i mean encryption in Bitcoin)
I know this is 2 years later but the reason is that information gets lost.
You AND two bits A and B, and you get a 0 you only know that A and B were not both 1, but you don't know if A was 0 or B was 0 or both were 0. This makes it hard to reverse engineer
are there any lectures on SHA-512
+Saurabh Parekh Unfortunately not. However, SHA-512 is not that different from SHA-1. Once you understood SHA-1, SHA-512 shouldn't too difficult. (Note that SHA-3 is completely different from SHA-1 und -2). Cheers, christof
You can also refer Foruzan's Cryptography book for SHA-12. It has detailed explaination of each round and so on.
Now, coming to SHA-3, do you plan to offer a video lecture on it please?
It is quite convoluted and all I am seeing is the push for its adoption for most of the future hash designs...
He actually did the SHA-3 what's a amazing professor, th-cam.com/video/JWskjzgiIa4/w-d-xo.html
Please make a video regarding sha-3