12,368 reputation
11352
bio website vyznev.net
location Helsinki, Finland
age
visits member for 3 years, 3 months
seen 16 hours ago

I'm a PhD student in biomathematics, working on stochastic individual-based models of evolution in spatially structured populations. My other interests include cryptography, programming games and puzzles, photography and graphic design.

I started programming (in AmigaBASIC) when I was 10 years old. Nowadays, I'm most comfortable using Perl, C and JavaScript. I know Java and PHP too, but I can't really say I like them. I also know some Python, but not as much as I'd like.


CC-Zero Please consider any (original) code I post to Stack Overflow and other Stack Exchange sites to be released under CC-Zero unless stated otherwise. You may do whatever you want with it and don't have to credit me in any way, although of course that would be nice.


I'm the main author and maintainer of the Stack Overflow Unofficial Patch (SOUP), a user script for browsers with GreaseMonkey-compatible user script support (Firefox, Chrome, Opera, possibly Safari) that fixes or works around a number of outstanding issues with the Stack Exchange user interface.

I tend to answer a lot more questions than I ask. Some answers I'm rather proud of:


Oct
21
comment How does one use AES block cipher modes of operation?
This should be specified in SP 800-38A (specifically, look in Appendix B). Anyway, the usual method is to send the initial counter value with each message, and to increment the counter by 1 for every subsequent block in the message. (It's possible to leave out the initial counter value if the recipient can reliably infer it from some other data, such as a message number.) And what you seem to be forgetting is that the key is also needed for successful decryption. :)
Oct
20
awarded  Sportsmanship
Oct
20
revised Does MAC provide origin authentication? Why not just use symmetric encryption?
added 842 characters in body
Oct
20
answered How vulnerable is RSA when using it to encode ~1000s of datasets with 500bytes each? How easy can the private key passphrase be hacked?
Oct
20
comment Complexity class of an idealised version of Bitcoin's proof-of-work (hashcash)?
Without analyzing the specific hash function used, I don't see how we can even show totality. For an arbitrary hash function (or a random oracle), there's no a priori guarantee that any input hashes to a value less than $x$, although it's extremely likely that one in fact does.
Oct
20
answered Does MAC provide origin authentication? Why not just use symmetric encryption?
Oct
20
comment Safety when disclosing hashes of secrets used to calculate other secrets
What's the security goal of the overall scheme? In particular, if it's to prevent anyone else from later pretending to have known the secret before you published it, how do you plan to stop a potential pretender from simply relaying all queries to you?
Oct
19
revised security-definition wiki description
rewrite
Oct
19
revised security-definition wiki excerpt
rewrite
Oct
19
comment Non-linearity of a boolean function
I've retagged this question, since it's certainly not about functional-encryption. However, if anyone can think of any more specific appropriate tags, feel free to add them.
Oct
19
revised Non-linearity of a boolean function
edited tags, copyedits; edited tags
Oct
18
answered What is the difference between a 'cipher' and a 'mode of operation'?
Oct
18
revised What is the difference between a 'cipher' and a 'mode of operation'?
edited tags
Oct
18
comment Secure order preserving hash function
@pg1989: Interesting. Can you describe this "something almost as good" in more detail? (In particular, I don't suppose it helps to avoid the binary search attack, since that's a generic plaintext recovery attack against any OPE scheme that allows encryption oracle access.)
Oct
18
revised How do these figures represent a boolean function?
edited tags
Oct
18
revised How do these figures represent a boolean function?
edited body
Oct
18
answered How do these figures represent a boolean function?
Oct
17
answered Increasing number of rounds in AES
Oct
17
revised How to hack the new save encryption on ipad for uplink?
deleted 1 characters in body
Oct
17
revised How to hack the new save encryption on ipad for uplink?
partial revert, format file header "magic words" as code, add link to related question