Re: [Cryptography] XORing plaintext with ciphertext

It depends on the encryption scheme used. For a stream cipher (including AES in counter or OFB mode), this yields the keystream. If someone screws up and uses the same key and IV twice, you can use knowledge of the first plaintext to learn the second. For other AES chaining modes, it's less

[Cryptography] XORing plaintext with ciphertext

Got a question that's been bothering me for a whlie, but it's likely purely academic. Take the plaintext and the ciphertext, and XOR them together. Does the result reveal anything about the key or the painttext? -- Dave ___ The cryptography mailing

Re: [Cryptography] XORing plaintext with ciphertext

-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Sep 7, 2013, at 12:14 AM, Dave Horsfall d...@horsfall.org wrote: Got a question that's been bothering me for a whlie, but it's likely purely academic. Take the plaintext and the ciphertext, and XOR them together. Does the result reveal

Re: [Cryptography] XORing plaintext with ciphertext

Thanks for the response; that's what I thought, but thought I'd better ask (I'm still new at this crypto game). -- Dave ___ The cryptography mailing list cryptography@metzdowd.com http://www.metzdowd.com/mailman/listinfo/cryptography

Re: [Cryptography] XORing plaintext with ciphertext

On Sep 7, 2013, at 4:13 AM, Jon Callas wrote: Take the plaintext and the ciphertext, and XOR them together. Does the result reveal anything about the key or the painttext? It better not. That would be a break of amazing simplicity that transcends broken. The question is much more subtle

Re: [Cryptography] XORing plaintext with ciphertext

* Dave Horsfall: Take the plaintext and the ciphertext, and XOR them together. Does the result reveal anything about the key or the painttext? Yes, their length. ___ The cryptography mailing list cryptography@metzdowd.com