SpiceCrypt: A Python library for decrypting LTspice encrypted model files
Comments
rshm
Schlagbohrer
yes please. I want to destroy the business model of making me pay money for hardware (understandable because it is made of atoms) and then making me pay for software blocks / DLC to be able to use the hardware
userbinator
The file header contains two 32-bit keys used to derive a substitution table index and step value for decryption.
In other words, obfuscation.
jtsylve
This is my work. Thanks for sharing! I'm happy to answer any questions, and feedback and requests are welcome.
snthpy
What is LTspice?
flowerthoughts
It's one of the most widely used electronic circuit simulator. It's basically a graphical interface to wire up differential equations, together with physical models of components (mostly semiconductors.)
There are other SPICE implementations, but Linear Technologies provides this program for free, and lots of manufacturers provide LTspice models for their components (of varying quality.)
snthpy
Cool, thanks.
ur-whale
> What is LTspice?
It's the best circuit simulator, whose creators did pretty much everything right with the following exceptions:
- using the wrong key for undo
- failing to understand that open-sourcing their baby would have made it 10 times better and 10 times more popular. But when you grow up in the hardware world, these concepts are very, very hard to understand.willis936
A few minor things:
Last year LTSpice actually switched to sane hotkeys. Hell has frozen over and our hands rejoice.
We should be careful with "best" without more qualifiers. It's a swiss army knife, but not very sharp. It's no replacement for an RF suite.
Archit3ch
> best circuit simulator
QSPICE (made by the author of LTspice) claims to be 10x faster.
Also, LTspice cannot do symbolic transformations, so that places an upper limit to its utility.
_fizz_buzz_
LTSpice is awesome, but the user interface is an acquired taste ...
IshKebab
Seems to be standard in the EDA world. Look up how you copy/paste in Eagle. Or what happens to wires when you move a component in a KiCAD schematic.
Schlagbohrer
Now if only they could decrypt Texas Instruments' models
jtsylve
I've got it working. Will update soon.
jtsylve
File a feature request on github with some background details and I'll look into it!
matthewdipo
[dead]
Coming from a brief failed attempt of using ghidra to see if keys were part of binary, this is a welcome news.
Next on wishlist is someone doing the same for encrypted fpga verilog blobs.