Tool to decrypt/encrypt with circular bit shift, a function that shifts all bits of a binary value thanks to a rotation operation.

Circular Bit Shift - dCode

Tag(s) : Modern Cryptography

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The **Circular Bit Shift** encryption uses data in binary format, such as the ASCII encoding.

__Example:__ `DCODE` is coded in binary ASCII `01000100 01000011 01001111 01000100 01000101` or `44 43 44 45 4F` in hexadecimal.

The encryption starts by cutting the binary data into blocks of size `B` bits (if B=8 then the shift is applied to each byte) and for each block, making it undergo a circular rotation of `N` bits (+1 = shift left, -1 = shift right).

__Example:__ `01000100` shifted by N=-1 becomes `00100010` (the right bit is moved on the left).

The message `DCODE` split into 8bits blocks and shifted by N=-1 becomes `00100010 10100001 10100111 00100010 10100010` or `22 A1 A7 22 A2` in hexadecimal.

For a block size B, an offset of -X or B-X is identical (modulo B).

Decryption requires knowing the settings (block size and offset) used. It is identical to encryption except for the offset N which takes the opposite value (encryption with N = 1 is equivalent to decryption with N = -1).

__Example:__ The binary message `00100010 10100001 10100111 00100010 10100010` encrypted with an offset of 1 bit.

`00100010` is shifted by N=1 as `01000100` (the left bit is moved on the right).

The message becomes `01000100 01000011 01001111 01000100 01000101` that is ASCII values for `DCODE`.

The message is usually presented in a raw format or at best in hexadecimal or binary format, as the characters resulting from the processing are not always printable characters.

Test all possible block sizes and offsets and keep those that show ASCII values of alphanumeric characters.

dCode attempts all sizes between 2 and 32 and all offsets between +1 and +31.

dCode retains ownership of the online "Circular Bit Shift" tool source code. Except explicit open source licence (indicated CC / Creative Commons / free), any "Circular Bit Shift" algorithm, applet or snippet (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any "Circular Bit Shift" function (calculate, convert, solve, decrypt / encrypt, decipher / cipher, decode / encode, translate) written in any informatic language (Python, Java, PHP, C#, Javascript, Matlab, etc.) and no data download, script, copy-paste, or API access for "Circular Bit Shift" will be for free, same for offline use on PC, tablet, iPhone or Android ! dCode is free and online.

Please, check our dCode Discord community for help requests!

NB: for encrypted messages, test our automatic cipher identifier!

circular,rotation,shift,bit,binary

Source : https://www.dcode.fr/circular-bit-shift

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