Babel: An Untyped, Stack-based HLLΒΆ
| Authors: | Clayton Bauman |
|---|---|
| Time: | 10:20-10:50 |
| Session: | https://thestrangeloop.com/sessions/babel-an-untyped-stack-based-hll |
| Link: | http://babelscript.net |
| Slides: |
Going to explain how it works, and demonstrate it using the reference implementaiton. Began devleoping babel around 2006. In 2005 it was revealed that the NSA was spying on US citizens. The security flaws were made possible in some cases by backdoors inserted by NSA, et al. Today the emphasis of ownership is on those of the designer. Babel attempts to shift that to the rights of the user and the system owner.
Babel 1.0 will use public key crypto to verify that code is allowed – by the user – to execute. This means that the user decides who they trust to write software.
Babel is a stack based, untyped langauge. It’s not a “pure” language: some (many?) actions can have side effects. Although Babel is untyped, it does support tags, which allow you to assign string descriptors to pointers.
The core babel data structure is called the bstruct. This is the underlying container for all data in Babel. Strings, integers, unsigned, floats, are all stored as values in lfaf-arryas. No pointers can be stored ina leaf-array.
Ordeiinary pointers are stored in nitnerior-arrays: overy points in an interior-array must be initialized and valid. No values can be stored in an interior array.
[ overview of in memory data structure for Babel ]
Code is data in Babel.
[ example ]
And the following are equivalent:
(val "Hello")
(val 0x6c6c6548 0x6f 0xffffffff00)
The virtual machine, the BVM, is also a bstruct. There are three stacks: the down stack (dstack), up stack (ustack), and managed stack (rstack). Code-list is a linked list containing data operands, etc.
The Bable interpreter uses a small boostrap, which is also written in Bable. This bootstrap loads and begins execution of your program. The reference implementation is written in C, with a Perl front end parser (based on sparse.pl). In the future it will have a built in parser instead of using Perl, and include a wide selection of crypto primitives (libtomcrypt).
[Lots of time spent discussing stack and memory internals of Babel. This would be great for situations where I thought I might want to use Babel and wanted to develop a deep understanding. Unfortunately not at all clear to me when I might want to use Babel at the moment.]