Join Log in
Score:1
whatevahhh avatar Crypto

How does one produce this in the linear cryptanalysis of DES

ma flag
whatevahhh

I understand how this linear approximation board below is produced, enter image description here

but I can't understand how this second board is produced using the first one enter image description here

and finally how the pilling-up lemma values are calculated

( o in S 12 the approx. Λ 1 = X5 XOR X7 XOR X8 XOR Y 6 has bias +1/4

o in S 22 the approx. Λ 2 = Y 6‘ XOR Z 6 XOR Z 8 has bias –1/4

o in S 32 the approx. Λ 3 = Z 6‘ XOR W6 XOR W8 has bias –1/4

o in S 34 the approx. Λ 4 = Z 1‘ 4 XOR W14 XOR W16 has bias –1/4)

Which finally leads to this:

enter image description here

I know this might seem like a lot but I am really stuck and all the documentations and articles I find online aren't really being much of a help, and from what I've seen here people seem really helpful on stuff like this.

Thanks in advance!

36
0 + 0
des
kelalaka avatar
in flag
kelalaka
By searching, see Matsui's paper about how many searches they did. The Hayes article is just an introduction to the field...
1
Reply
ธงชาติไทย
Elon Musk
I sit in a Tesla and translated this thread with Ai:

mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.