All Questions
Tagged with chacha block-cipher
7
questions
1
vote
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340
views
ChaCha20 as a block cipher
Would it be possible to use ChaCha20 as a block cipher? With the key, the entire block function can be reversed.
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4
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0
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153
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Why Block Ciphers
I fail to understand what block ciphers can do that stream ciphers cannot.
Also aren't they construct able from one another.
prg(stream cipher) -> prf -> prp(block cipher)
Any practical example ...
- 41
0
votes
1
answer
236
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What is the lightest cipher that provides AES like security?
The lightest, or fastest cipher, that is well known and quite secure like AES. Is ChaCha20 a good option? Are there any better alternatives that are faster but still as secure?
- 25
2
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1
answer
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XChaCha20 vs AES 128 security and speed
Is XChaCha20 with 256 bit key and 192 bit nonce more secure than 128 bit key 128 bit key nonce AES, due to using larger key/nonce sizes? Isn't it supposed to be faster due to being a stream cipher? (...
- 25
1
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1
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Can repeatedly encrypting a message with a secure cipher ever produce the original input like what happens in ROT13?
Lets say we have a message 'm'.
We encrypt 'm' using a stream cipher or any other type of cipher with cryptographic security that produces an output equal in length to the length of 'm'.
Then if we ...
- 13
5
votes
1
answer
229
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Latin dance family in block cipher
Is it secure to use Salsa20/ChaCha as the key schedule for a 512-bit block cipher using a public permutation in Even-Mansour construction?
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4
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0
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How secure is $\operatorname{AES256}_{\operatorname{ECB}}(\operatorname{ChaCha20}(\text{plaintext}))$?
Suppose I encrypt a bytestream using ChaCha20, and then encrypt the resulting ciphertext using AES in ECB mode. How secure is the combination?
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