Re: Inspired by Chris's HMAC cipher

On 10/17/2024 12:25 PM, Stefan Claas wrote:

Stefan Claas wrote:

Stefan Claas wrote:

Chris M. Thomasson wrote:

On 9/20/2024 4:17 AM, Stefan Claas wrote:

I came up with the following idea.
>
Register a webpage at nekoweb.org, use an API key
and send encrypted messages to the web page, which
later Bob and Alice can decrypt.[...]

>
To decrypt use the default key, except click on the SHA512 radio button,
then click decrypt:
>
http://fractallife247.com/test/hmac_cipher/ver_0_0_0_1?ct_hmac_cipher=a4f7cb5f3c7a0957d9517ad740b06a5d13a02e0affcb2882f700e388eec93f650c92e3b451915f04d2c0dd45f13e1ad5bfad03552937e2ff2602ec88dc3ccdce8b3076ec0addad4b41123297542709c292bb836850057363dbd2e7c7eb6f237db3e3d3d891600c880b92bbbe0b293a34bbc4994c81dba3deef421247965b01ef1cfca2ac91fc73b1511997cb09907e

>
Hi Chris, please reply here in plaintext. I do not have the passwort anymore.

>
Or for further communications, I would prefer that you use my minicrypt too,
because then we do not need to visit the WWW, for encrypted communications.
>
My pub key (save it as stefan.pem):
>
-----BEGIN PUBLIC KEY-----
tRxoeAmoI+0ygSbUYHBRpbYBDkC9+Q3rSTchzSXFHrU=
-----END PUBLIC KEY-----
>
https://github.com/706f6c6c7578/minicrypt

 Your ciphertext is also longer than minicrypt ciphertext.
 Your message with your HMAC cipher:
 a4f7cb5f3c7a0957d9517ad740b06a5d13a02e0affcb2882f700e388eec93f65
0c92e3b451915f04d2c0dd45f13e1ad5bfad03552937e2ff2602ec88dc3ccdce
8b3076ec0addad4b41123297542709c292bb836850057363dbd2e7c7eb6f237d
b3e3d3d891600c880b92bbbe0b293a34bbc4994c81dba3deef421247965b01ef
1cfca2ac91fc73b1511997cb09907e
 Your message with my minicrypt cipher:
 RzJ1JQ9XcXuvqozXkVDzTMOLVwOcZTboSrj+16/gZmU+l/0wrLy1Lj6tu+o24QHJ
Oo7OZ2XXhbf6PqdQ4mpGxDOB7QuasdrnKwPLUNrnUPgXgimjl/3f1HRcJz6pBQf2
Ywgh1TCpiZnydd+Clt8uj4dbXHYpSSBkG0NIchAauixcHzXAPlME233RW8VrddMi
tAYbJptlqHLB
 

Yeah, I am only representing the ciphertext in hex right now for the online version. Now, I could modify it to encode the ciphetext in base 64 or something a little more "dense", so to speak... Fwiw, here is a link to a C based test version, have you seen it yet?
https://groups.google.com/g/comp.lang.c/c/a53VxN8cwkY/m/XKl1-0a8DAAJ
;^)