Cryptography Stack Exchange
Cryptography Stack Exchange

Questions tagged [siphash]

A fast 64-bit PRF that can be used as a MAC

SipHash is a fast 64-bit PRF with a 128-bit key. It has been designed by Aumasson and Bernstein to be a fast MAC for short inputs, due to its key agility and low per message performance cost. It is used to implement hash tables in some programming languages.

Despite its name, it is not a secure cryptographic hash function.

External resources:

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Is SipHash cryptographically secure?

I'm evaluating different hash algorithms for use in my application. One of the kind of algorithms I am looking at are cryptographically secure ones to protect against DOS attacks. SipHash seems pretty great, but the creators seem very careful to…
GBleaney
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SipHash's (non-)collision resistance

I'm very new to cryptography, and I need help understanding the security claims made in Aumasson and Bernstein's paper on the SipHash. In particular, I'm trying to understand the following statement at the end of section 3 (p. 6): We comment that…
Luis Casillas
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Same 64-bit preimage resistance security for SipHash and SHA-512/64?

If I have to chose a 64 bit preimage resistant hash function; will there be any difference in security between SipHash and SHA-512/64 (SHA-512 truncated to 64 bits)? How long will it take an attacker to find a 64 bit preimage (e.g., minutes,…
Chris
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Why is Siphash-128 considered "experimental"?

Why is Siphash-128 still considered "experimental"? What does this mean?
Demi
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Cryptanalysis of Marvin32 compared to SipHash

So I am curious about the security analysis of Marvin32, the randomized hash algorithm used in .NET (to prevent hash-table DoS). I found the source code here: marvin32.h, marvin32.c. At first glance, the construction looks really similar to that of…
Paya
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Does SipHash have 64 bit (second) preimage security?

I was not able to find an explicit statement about the first and second preimage security of SipHash-2-4 or SipHash-4-8 anywhere. I think it should be 64 bits, but I'd feel safer if somebody who has more experience with such hash functions could…
Chris
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Generate a unique 64 bit numeric database key without collisions at $2^{32}$ birthday threshold?

What is the best way to generate a unique 64 bit numeric database key from a string? For example: if the string is a URL, you could generate a 64 bit key using SipHash or by truncating a SHA256 hash to 64 bits, but collisions are likely at $2^{32}$…
espeed
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A fast non-cryptographic hash function that is "strong enough"?

I'm designing a simple one-time-password mechanism for authentication against a possibly-insecure server - i.e. I don't want to use symmetric shared secrets. The first idea that came into mind was using a hash-chain with a cryptographic hash…
Ozo
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Using cryptography to protect database integrity

I'm designing a micro-services system where each service manages some set of entities (User, Account, e.g). I want to be able to verify the authenticity of entity identifiers (e.g User-Id and Account-Id), to make sure the identifier was actually…
somdoron
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Parallel MAC vs doubled rounds for SipHash, KMAC and others

SipHash 4-8 is documented by the authors as being about half the speed of SipHash 2-4 and is obviously the more conservative option. I was wondering from a security perspective how this would compare with performing SipHash 2-4 with two different…
MotiNK
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SipHash-1-3 128 bit variant

I came across a 128 bit variant of the SipHash-1-3 function (as opposed to the original 64 bit output). I tried looking for any public cryptanalysis of this function but couldn't find any. Moreover, in this particular usage of sip128-1-3 the keys…
adamk
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Short-input (<= 128 bit), short-output (<= 10 bit) MAC

I am faced with a problem of selecting an appropriate message authentication code (MAC) for a particular application. These are the constraints: I have two 64-bit integers $r_a$ and $r_s$ as input, where: $r_a < 2^{52}$ and $r_s < 2^{52}$ $r_a$ is…
asnfkjsdx
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