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| age | ||
| visits | member for | 1 year, 6 months |
| seen | May 12 at 19:53 | |
| stats | profile views | 0 |
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May 5 |
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What length should the padding be when encrypting or signing with RSA? Oh.. and thank you very much for your answer! |
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May 5 |
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What length should the padding be when encrypting or signing with RSA? @JohnDeters I don't care if two identical messages yield the same output. I'm trying to implement a licensing system. (See my comments to fgrieu's answer and my other recent question on the site .) And I'm mainly concerned with signing. |
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May 5 |
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What length should the padding be when encrypting or signing with RSA? a) I should calculate a separate padding (is that the term instead of salt?) for each computer (in a random-like manner). And perhaps add a really-random part to it. b) The padding should be at least $256 + (2/3) n$ bits (which, if $n$ is 2048 - would leave me with a maximum of 426 bits (=53 bytes) for the computer-id (or its hash). Did I understand correctly? |
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May 5 |
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What length should the padding be when encrypting or signing with RSA? So... I understand from your answer that in the signature scheme where (as a licensing system) I'm signing a user's computer's hardware-id and returning it to the user's computer - having my application on that computer verify that the returned value is indeed the signed hardware-id: the following will be true: |
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May 3 |
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What length should the padding be when encrypting or signing with RSA? @fgrieu I'm converting a byte array to a BigInteger but first concatenating a new byte array to the end of the original one (before converting to BigInteger) and using that as $m$ in $m^d \bmod n$. |
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May 3 |
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What length should the padding be when encrypting or signing with RSA? @fgrieu concatenation. $(m+salt)^d \bmod n$ - Thanks. I was looking for that formatting. |
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May 3 |
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What length should the padding be when encrypting or signing with RSA? @fgrieu m^d mod n VS (m+salt)^d mod n |
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Aug 10 |
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What is the length of an RSA signature? OK, I found the answer to that one here: stackoverflow.com/a/2922135/939213 - Yes, the modulus itself is 2048. |
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Aug 10 |
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What is the length of an RSA signature? Thanks. And when we say 2048 bit encryption - Do we mean that N itself is 2048 bit? |
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Aug 10 |
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What is the length of an RSA signature? But since the signature is $m^d \bmod n$ - It seems that the length can even be $0$. Or are you referring to a system that will pad it as an extra feature? |
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Apr 30 |
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How to sign a message using RSA? Thanks. As for BigInteger - See this in .NET 4.0. |
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Apr 30 |
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Why hash or salt when signing? Thanks for the answer. |
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Apr 27 |
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Why hash or salt when signing? Thanks. So if my message is short enough – there's no need. Correct? |
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Apr 27 |
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Why hash or salt when signing? Thanks. But I'm referring to signing, and so it seems unlikely (correct me if I'm wrong) that someone will have a table for a rainbow attack for all 100 bit combinations. |
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Apr 25 |
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How to sign a message using RSA? @CodeInChaos So you're saying it can't realistically be done in a simple manner (i.e. without spending a week studying cryptography), right? By the way, if you have some solution as to how I can create an activation key in a web hosting environment – where they have RSACryptoServiceProvider blocked – I'd be happy to hear about it. |
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Nov 23 |
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Is a RSA-signature of some identifying data a safe way to implement a license key? @Polynomial Thanks for that important information! |
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Nov 21 |
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Is a RSA-signature of some identifying data a safe way to implement a license key? @PaŭloEbermann Thanks for bearing with me. I edited the question for (a little) clarity. Knowing the ID is not important, because the program will retrieve the real ID of the operating system. See also my previous comment (to this.josh ) |
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Nov 21 |
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Is a RSA-signature of some identifying data a safe way to implement a license key? @this.josh If someone is computer-savvy enough to do that – he’ll probably be able to de-compile the program anyway, and remove the security check. My main goal at the moment is to thwart someone from creating a program that will create license keys when given a product ID. |
