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Feb
7
revised Common Modulus Attack not reproducible
Add link
Feb
7
revised Common Modulus Attack not reproducible
Polish
Feb
7
revised Common Modulus Attack not reproducible
Full problem statement
Feb
7
revised Common Modulus Attack not reproducible
Contrast with other answers
Feb
7
answered Common Modulus Attack not reproducible
Feb
7
revised Compression in key generation of DES algorithm
Give alternate explanation
Feb
7
answered Compression in key generation of DES algorithm
Feb
7
comment Compression in key generation of DES algorithm
Anything wrong with the explanation and drawing in Wikipedia? Notice that in DES, the convention is that the bits are numbered from 1 onwards, with 1 being the first or left bit, or the most significant bit of in the big-endian translation to integer of a bitstring, or the most significant bit in the first or left octet in an octet string. Also, the output of PC2 is subdivided into 8 bitstrings of 6 bits (hence the presentation of the table as 8 lines of 6 entries), corresponding to S1 thru S8.
Feb
6
comment Common Modulus Attack not reproducible
@Ricky Dememer: yes; you reduced the problem to finding an efficient way to compute the meadow inverse of a given $c$ modulo $n$ of unknown factorization when $c$ has no regular inverse, and is not $0$.
Feb
5
comment Security of RSA for paranoids with padding?
@Maarten Bodewes: no, I did not make any progress, or have had time to seriously explore potentially interesting alternatives to the dominant asymmetric crypto for Smart Cards (2-primes RSA, ECDSA per FIPS 186-4).
Feb
4
comment Secure blinding factor switching at malicious server-side (Switching in One Time pad)
@user153465: the second paragraph in the answer tries to address that. The adversary is free to compute any function of $v_1$ and $v_2$, like $v_4(v_1,v_2)=(v_1+v_2)^{v_1-v_2}$, or $v_3(v_1,v_2)=v_1\cdot v_2$, anything goes, that has no influence on the demonstration given. This is just extra added to the question's statement, obscuring it, that we want to get rid of to focus on the expressions involving $a$, or $z_1$, $z_2$ or other things not known to the adversary.
Feb
4
revised How does RIPEMD160 pad the message?
polish code comments
Feb
4
comment How does RIPEMD160 pad the message?
@seeker: I see no issue with the reference implementation; it works fine for me, with the (documented) issue is that it uses a non-portable definition of the 32-bit type dword. If the compiler barks, that should be changed from unsigned long to uin32_t from <stdint.h>, or just unsigned on many modern machines. Try to use that reference code from the simple main program that I posted.
Feb
4
revised How does RIPEMD160 pad the message?
add comments
Feb
4
revised How does RIPEMD160 pad the message?
Add a comment
Feb
4
revised How does RIPEMD160 pad the message?
Add reference code
Feb
4
revised Secure blinding factor switching at malicious server-side (Switching in One Time pad)
slightly simplify
Feb
4
answered Secure blinding factor switching at malicious server-side (Switching in One Time pad)
Feb
4
revised How does RIPEMD160 pad the message?
Shorten note
Feb
3
revised How does RIPEMD160 pad the message?
Note on consequence of the mixed endianness