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| bio | website | |
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| location | ||
| age | ||
| visits | member for | 1 year, 9 months |
| seen | 1 hour ago | |
| stats | profile views | 105 |
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Mar 28 |
reviewed | Approve suggested edit on Taking advantage of one-time pad key reuse? |
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Mar 28 |
answered | Can two rc4 encoded messages be XORed and decrypted if encrypted with the same key? |
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Mar 27 |
reviewed | Approve suggested edit on one-time pad key related attack |
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Mar 26 |
comment |
How to use HMAC for large ciphertexts over TLS @rsa: Well, since we typically don't use TLS to communicate with smart cards, well, that's a different question. However, the gist of it is that it's possible to compute an HMAC incrementally; that is, give it the data being HMAC's in pieces; with a fixed amount of storage, we're able to compute the HMAC of the entire message, even though we never saw the entire message at any one time. |
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Mar 25 |
reviewed | Approve suggested edit on SSTP MSCHAP-V2 Authentication before SSL or after SSL Session |
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Mar 25 |
answered | How to use HMAC for large ciphertexts over TLS |
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Mar 25 |
comment |
Where can I begin to study the math behind modern cryptography? @Abdullah: no, the AES designers didn't pick 1,1,2,3 for the mix columns solely for hardware implementation. Their first criteria was that they formed an MDS matrix; if you replace those numbers with numbers that don't form an MDS matrix, the security proofs of AES against differential and linear cryptanalysis fall apart. |
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Mar 25 |
comment |
Where can I begin to study the math behind modern cryptography? @PaytonTurnage: this is why this is such an excellent answer; unless you understand how cryptanalysis is done, that is, how cyphers can be broken, you really don't understand cryptography (that is, you won't understand why things are designed the way they are). And, the only way to understand cryptanalysis is to do cryptanalysis. |
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Mar 25 |
comment |
Where can I begin to study the math behind modern cryptography? This is a rather poor answer; no, you don't need to spend 10 years studying Abstract Algebra and Computer Science. He probably should have stopped at "I would guess that...". For example, when we're working with a finite group or field, no, we don't make approximations to exact calculations; we perform the operation precisely. |
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Mar 22 |
comment |
How to calculate y value from ((y*y) mod prime) efficiently Oops, sorry, but 2 will never have have a multiplicative inverse modulo $p-1$, because $p-1$ is always even. Se fgrieu's comment for the correct answer. |
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Mar 22 |
comment |
How to efficiently generate a stream of independent, but biased random bits? @PaulCrowley: actually, it would appear to me that this algorithm is extremely FP friendly; with IEEE math, I believe it treats the input bias as a precise rational; the only operation that can get a rounding error is the 'bias = bias-1', and that can happen only if 'bias < 0.5' entering that step, in that case, we output 0, and so the rounding error is irrelevant. (Oh, and "Hi, Paul!") |
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Mar 21 |
revised |
How large should a Diffie-Hellman p be if the messages are encrypted? Expanded explination |
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Mar 21 |
comment |
Encrypting and Decrypting a 19-digits long BigInteger @RickyDemer: actually, with what I suggested (using 3DES in ECB mode), the attacker would have no control over what it decrypts to (other than that it's not what the original number was) |
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Mar 21 |
answered | How large should a Diffie-Hellman p be if the messages are encrypted? |
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Mar 20 |
answered | Encrypting and Decrypting a 19-digits long BigInteger |
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Mar 20 |
comment |
How does the rand() function in C work? That implementation is just one possibility; in fact, the C standard provides a different sample implementation (similar, but with a different multiplier and constant). Different C compilers/libraries are perfectly free to use something else (and likely will). |
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Mar 20 |
answered | How does the rand() function in C work? |
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Mar 19 |
revised |
Brute forcing an HMAC Added a sumamry |
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Mar 19 |
answered | Brute forcing an HMAC |
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Mar 19 |
answered | Selecting a large NUMS Safe prime |
