10,073 reputation
12451
bio website github.com/CodesInChaos
location Frankfurt, Germany
age
visits member for 3 years, 4 months
seen 25 mins ago

Jul
30
reviewed Reject suggested edit on Counter mode secure hash algorithm
Jul
30
reviewed Edit suggested edit on Is a second preimage attack on MD5 feasible?
Jul
30
revised Is a second preimage attack on MD5 feasible?
Introduced the new "merkle" tag as multiple questions talk about it.
Jul
30
reviewed Reject suggested edit on Why is feed-forward mechanism used in hash functions?
Jul
30
reviewed Reject suggested edit on
Jul
30
reviewed Reject suggested edit on What is the purpose of using different hash functions for the leaves and internals of a hash tree?
Jul
30
reviewed Edit suggested edit on Why is H(message||secret_key) not vulnerable to length-extension attack?
Jul
30
revised Why is H(message||secret_key) not vulnerable to length-extension attack?
Introduced the new "merkle" tag as multiple questions talk about it.
Jul
30
reviewed Reject suggested edit on Efficient Incremental Updates to Large Merkle Tree
Jul
30
reviewed Reject suggested edit on
Jul
30
revised Abstracting primitives and modes of operation
edited tags
Jul
30
comment Assuming a 1024qb quantum computer, how long to brute force 1024bit RSA, 256bit AES and 512bit SHA512
For 3 and 4 it's clearly forever (cost of at least $2^{256}$, and for 2 it's still extremely long (cost of at least $2^{128}$.
Jul
28
comment Security of a 3-party key exchange protocol
@minar One problem with this description is that it doesn't describe what the parties do with the messages they receive. For example if the server validates that $S$ is in the expected place in the message then it can distinguish message 1 from message 3. It's also not clear to me why it'd be a problem if $S$ mixes up $I$ and $R$ since it'd still send them a proper session key. | Analyzing real protocols is certainly much nicer than analyzing underspecified theoretical protocols :)
Jul
28
comment Security of a 3-party key exchange protocol
Can the adversary communicate with S using their own identity E? If you combine that with an unauthenticated stream cipher as encryption you'd get another vulnerability.
Jul
28
comment Security of a 3-party key exchange protocol
What properties does your encryption provide? Is it authenticated encryption? Is it malleable? What about proper IVs?
Jul
28
comment Security of a 3-party key exchange protocol
do you really want k(I,R) in step 3? Or k(R, S)?
Jul
28
reviewed Approve suggested edit on multiparty-computation tag wiki
Jul
28
comment Cryptography used for login and signing transactions
Such short numbers point to symmetric crypto.
Jul
26
revised split up sha256 hash and compare indiv block results
deleted 10 characters in body
Jul
25
reviewed Approve suggested edit on Hash function based on pseudorandom functions and security