Questions tagged [poly1305]

Poly1305-AES is a cryptographic message authentication code (MAC) written by Daniel J. Bernstein. It can be used to verify the data integrity and the authenticity of a message.

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xChaCha20 Block Keys for Poly1305

So xChaCha20 has a nonce size large enough to safely use a random nonce with the same key. Poly1305 generally uses the first block of the cipher's output to generate its nonce. For xChaCha20 it would ...
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Impact of partitioning oracle attacks on file encryption?

I've just learned about partitioning oracle attacks recently, and I would like to clarify some things that are a little foggy to me right now. According to this thread, The aim is the recovery of a ...
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Implement deterministic authenticated encryption using libsodium

Note: this is my first question on stack exchange, let me know if you miss some details to answer and I will edit the question accordingly Context I'm willing to create a git encryption tool (...
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How to increase Poly1305 performance?

I was analysing the Chacha20 algorithm and the Poly1305 MAC generation from RFC 7539. It seems that the Chacha20 is quite faster compared to AES on CPUs without hardware support like AES-NI. But ...
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Why are integers considered "little endian" in ChaCha20 function?

Why the ChaCha20 - IETF algorithm that generates 512 bit keystream per 32 bit counter (that gets incremented), considers "the input words" that form the internal state as little endian ? ...
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Secretbox- algorithm Poly1305 and cipher Xsalsa20

I use Rclone, which uses Secretbox to authenticate and encrypt data. Secretbox uses the Poly1305 authentication algorithm and the Xsalsa20 symmetric flow cipher. This whole process takes some time (...
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How does Poly1305 use $2^{130}-5$?

How is the number $2^{130}-5$ used in Poly1305? It operates on blocks that are 128 bits long, but the number has 130 bits. I don't understand how it is used. This comment makes me think it uses ...