2,926 reputation
1518
bio website
location United States
age
visits member for 2 years, 5 months
seen 7 mins ago

4h
comment Composing hashes and/or MACs
That works for the usual conditions of unforgeability and pseudorandomness. $\:$ On the other hand, it does not work for the intermediate property of being a privacy-preserving mac. $\;\;\;\;$
5h
revised Is anyone aware of Du atallah multiplicative secret sharing scheme for dot products for > 2 party scenario?
fixed link
6h
comment Which commitment scheme is better for malicious models
What is "the one based on digital signatures"? $\;$
16h
revised How can I convert numbers into prime numbers?
fixed grammar and removed irrelevant tag
16h
revised SSL-like protocol with public-key hard-coded in the client
fixed grammar and a typo
1d
comment Security of RSA for paranoids with padding?
One could just apply naked RSAP to something chosen at random and use a random oracle's $\hspace{.68 in}$ value at that thing as a key, although this approach would increase the ciphertext overhead. $\hspace{.96 in}$
1d
comment Sequence of Encrypting RSA like Chaum Blinding scheme
One would check the signature's authenticity by checking whether or not $\:$ pow(claimed_signature,e,n) == digest(message) $\:$ is satisfied. $\;\;\;$ "Will unblinded_signed_msg == pow(message,d,n) satisfy" what condition? $\;\;\;\;\;\;$
1d
comment Sequence of Encrypting RSA like Chaum Blinding scheme
Are you using Python? $\:$ Is "wayyy to long" more than 15 seconds? $\:$ My laptop was able to evaluate that for 25 random 2047-bit triples in under 7 seconds. $\:$ I would tackle this by making sure you're never computing pow(blinded_message,d), and then looking for other bugs you might have. $\:$ As far as I can see, the value of pow(signed_msg,r**-1,n) is completely irrelevant. $\:$ (I don't see a reason for anything involving r to be in the exponent.) $\;\;\;\;$
1d
comment Sequence of Encrypting RSA like Chaum Blinding scheme
Which of the posts in that link are you talking about? $\;\;\;$ One signs on a blinded_message by computing $\:$ (blinded_message)^d % n $\;$. $\;\;\;\;\;\;$
1d
revised Sequence of Encrypting RSA like Chaum Blinding scheme
gave bound regarding privacyparameter
1d
comment Sequence of Encrypting RSA like Chaum Blinding scheme
Neither party computes r**d. $\;\;\;$ (You may want to actually look at the link I gave for $\:$ (blinded_token)^d % n $\;$.) $\;\;\;$ I'm about to edit in a bound on the blindness in terms of privacyparameter. $\;\;\;\;\;\;$
1d
revised Does AES-128 have the same strength as AES-256 with a padded key?
fixed grammar and changed spacing
1d
revised Sequence of Encrypting RSA like Chaum Blinding scheme
addressed OP's comments
2d
answered Sequence of Encrypting RSA like Chaum Blinding scheme
Apr
13
answered How do they implement MAC in TLS?
Apr
13
comment Given a message and signature, find a public key that makes the signature valid (ECDSA)
Usefully, the change you describe would also stop a hash collision from immediately yielding $\hspace{.9 in}$ a way to violate unforgeability for every public key. $\;$
Apr
12
awarded  Strunk & White
Apr
12
revised Why does HMAC need a fixed length padding?
improved grammar
Apr
12
comment Why should a signature use PSS padding in RSA?
In addition to issues related to RSA, what your first paragraph describes is analogous to encrypt-and-MAC.
Apr
12
comment Why are collision attacks important when talking about MAC schemes?
I thought that would be about the chaining variable's length, rather than the MAC's length. $\hspace{.95 in}$