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Java and security expert with over 10 years of experience with the language and with the practical application of cryptographic protocols - including the design of protocols within international standardization bodies. Creator of a heavily used common criteria certified product. Over 30 years of experience with computers. Likes kids, cats, reading, movies and several sports.


Oct
16
comment Does NSS fully implement PKCS 11?
OK, but I don't see anything in your question that assumes that this is about using the PKCS#11 interface from NSS. Especially the title seems contradictory. And I think that your comment about the PKCS#11 functions supported by NSS basically answers your own question :)
Oct
16
revised Comparing Files: Is it better to use multiple hash algorithms or just one?
added 72 characters in body
Oct
16
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
OK, I see now. Sorry about that, you can just run until you find an inequality, and only test further if you don't find any. Slightly different use case as within most schemes.
Oct
16
revised AES: Guess Password using the unencrypted text?
added 174 characters in body
Oct
15
comment AES: Guess Password using the unencrypted text?
Well, the lazy was a bit tongue in cheek. PGP makes a lot of sense here and you can encrypt without providing a password at all.
Oct
15
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
@Gutblender True, makes much less sense for small files. Although hashes of course are really small, 32 bytes at most. And you could create a hash tree and check a complete folder at once as well.
Oct
15
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
I understand that, but are you only going to copy files with no obvious inequalities? So, if there is no obvious inequality, you leave it? Wouldn't that cause corruption?
Oct
15
answered AES: Guess Password using the unencrypted text?
Oct
15
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
How can you be prepared for collisions? If you see the same hash value, you will skip (and your result will be incorrect). If you don't you are back to square one.
Oct
15
comment How would I write my own asymmetric encryption algorithm (not RSA, DES etc)?
1. Define a one way trapdoor function, 2. fall through it :)
Oct
15
comment How would I write my own asymmetric encryption algorithm (not RSA, DES etc)?
Personally I would just go for RSA instead of creating one of your own. It's one of the most simple algorithms, but fully understanding RSA is hard enough. There are plenty explanations out there, and many people can provide help. After that you've at least an idea of which pit falls to avoid.
Oct
15
answered Comparing Files: Is it better to use multiple hash algorithms or just one?
Oct
15
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
@LightBit Or if you can pre-compute hashes they will speed up the protocol later on. If you use something like ZFS then you get this functionality for free, if I'm not mistaken.
Oct
15
comment Comparing Files: Is it better to use multiple hash algorithms or just one?
If you are not afraid of obnoxious users creating deliberate hash collisions then you could of course just use rsync or one of the many related utilities.
Oct
15
comment Does NSS fully implement PKCS 11?
I would seriously think about using the well standardized PKCS#11 interface directly instead. Why do you want to use the subset of the functionality, hidden behind the proprietary API provided by NSS?
Oct
15
comment Elliptic curve parameters
@zahra Close to that number anyway (the order is an integer, which is slightly smaller than 2^192). But beware that e.g. the key size of RSA does not implicate the same thing; there will be significantly less key pairs for RSA.
Oct
15
comment Elliptic curve parameters
@zahra Normally we use pre-generated "named" curves provided by brainpool, NIST or a set of other "safe curves". More info at SafeCurves. Only secret $s$ will be randomly chosen and public point $w$ can then be calculated by the user.
Oct
15
comment Does NSS fully implement PKCS 11?
Note that e.g. the PKCS#11 provider of Oracle in Java does support NSS, but it does require additional configuration as well.
Oct
15
comment Does NSS fully implement PKCS 11?
That's all about using the PKCS#11 interface for (smartcard etc) tokens. It's not about the NSS interface itself, to applications that use NSS. As far as I know, the NSS interface has many similarities with PKCS#11, but it doesn't declare all the functions of the PKCS#11 interface.
Oct
15
revised What is the history of recommended RSA key sizes?
deleted 2 characters in body