mathematica-encode
Imagine someone is giving you an awesome code. You want to analyze how it works, but when you look at it, it turns out to be
(*!1N!*)mcm
*#WyAFef9eath`UwFHOE49;C)RDE71Q3j/dYM9Da/OaAM*ou^)kw15h|T(+F>J'Me#1iO6
/>..Bf=vLDR4%}X0,5>"?Wd{ht"; |j.C.`:dT:<6\:+^SaDB6kwOHFosk z6JR`L}-TN8
KNT!6>L~Gbd}U%`m5Z_wX($!/&A}&l<W4'9]bmU7SLMS[,5Zlq(THSVf3%hjNB,0^)R}$=
iD>~LL#~iVE|aZBK[c1z6m\t.zSoCT(6>]<<eM[m"R.3+|:*8K\$_/Sa[T$W!y^&f=J>Rs
TYM9T6FpLSdMaY([m`qA!vLt/+#f;*&: g1lL]#goFSe3tKFK6IY9z(#>,c{-YY/H.S;OE
....
These random chars are a result of the Encode function of Mathematica. A way to make sure that your source code can not be directly edited.
Because the security mechanism doesn't use any keys it relies solely on security by obscurity. The safety of this function has already been discussed.
When I saw this function I took it as a challenge and tried to decrypt it via an ordinary chosen plaintext attack. It took around 8 hours when the unencrypted code appeared on my screen.
This code here, written in Python shows the encoding function. First it compresses every char by using Huffman coding and a fixed internal table. It then encodes the bitstream to some sort of two-byte base 95 Ascii representation.
The decoding function is not part of this repository. Feel free to revert my code :-)