Reputation
306
Top tag
Next privilege 350 Rep.
Access review queues
Badges
1 12
Newest
 Informed
Impact
~3k people reached

May
19
comment What should I think about these unique certificate serial numbers
The fingerprints are also short, 64-bits is not enough to really assume uniqueness. Is it? Also, these seems to expire pretty much annually, meaning new certificates will be issued regularly.
May
17
awarded  Informed
May
15
comment Inserting a backdoor into a cryptographic hash function
Is it possible to backdoor a hash function and still have it compatible with other implementations?
May
13
comment Is what i'm trying to do safe?
So essentially you hardcode the symmetric key at the endpoints and then negotiate an IV?
May
13
comment Is what i'm trying to do safe?
Without some kind of asymmetric key exchange I struggle to see the basis of the security. Are you relying on synchronized random number generators at each end?
May
12
comment Is what i'm trying to do safe?
The handshake itself only mandates SHA and MD5 I think. But I think the exact hash functions used for the KDF are variable in the latest specification. In any case, the actual handshake logic adds minimal overhead to your implementation. As @cpast was saying, the main overhead that a full TLS implementation adds will be in it's support for a wide variety of cipher suites, and there's no reason, even formally, that you are required to support any more than one of those permutations.
May
12
revised Is what i'm trying to do safe?
deleted 28 characters in body
May
12
answered Is what i'm trying to do safe?
May
11
comment Measuring entropy for a ciphertext only attack
@Thomas Pornin: where can I read more about your definition of entropy?
May
1
comment Alice and Bob's crush
So, if I understand it, Alice computes h^a (her affection), Bob computes h^b (his affection), then they both compute h^ab = h^ba, and they can then compare for equality without revealing their affection to eachother. I could not see the requirement that these operations be carried out modulo a prime number on the Millionaire's problem wiki page. Can you confirm that this is necessary for the scheme to be secure?
Apr
27
comment Permuted vectors
I think you need some function that checks if the permutation is in the original order, such as it's hash.
Mar
1
awarded  Popular Question
Jan
22
comment Automated testing of cipher security for import/export compliance
Yes, correct. Is that a reasonable question?
Jan
13
comment Automated testing of cipher security for import/export compliance
Very interesting. Rephrased the question to include import restrictions.
Jan
13
revised Automated testing of cipher security for import/export compliance
added 162 characters in body; edited title
Jan
13
comment Automated testing of cipher security for import/export compliance
It's a valid answer - upvoted.
Jan
13
comment Automated testing of cipher security for import/export compliance
I updated the question with the new information. I hope the question does not need to be edited anymore.
Jan
13
revised Automated testing of cipher security for import/export compliance
added 162 characters in body; edited title
Jan
13
comment Automated testing of cipher security for import/export compliance
The OpenSSL export ciphers are "exportable with respect to old US crypto regulations". I want to consider other countries export policies. Do you believe that export regulations are no longer a concern?
Jan
13
comment Automated testing of cipher security for import/export compliance
Updated the question to emphasise that this is not about analysis of the code, but of the security properties of the cipher. I imagine that such a system would be able to grade the strength of the cipher, where depending on this strength the cipher is deemed to be exportable or not exportable.