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Kaitai: Describe the structure of data, not how you read or write it

kaitai.io

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Re: Kaitai: Describe the structure of data, not how you read or write it

#41

Post by jchw »

floppy123 wrote: post #11
carom wrote: post #5

I do love kaitai and recently contributed a grammar, but both the title and the copy talk about writing. > Reading and writing binary formats is hard... Kaitai Struct tries to make this job easier... Kaitai cannot write data back out. [1] This is a major limitation for me. It would be nice to use it as a mutation engine for fuzzing, but without being able to write it back out, it is mostly just beneficial for analysi…

Any other lib that also generates Encoder/Writer code?

I wrote a sort-of adjacent library for Go at one point. I’m a bit stuck trying to figure out exactly what to do on 2.0 but it has a lot of Kaitai like features including an expression language for transforming things (on master version) and it supports writing structures out.

https://github.com/go-restruct/restruct

Re: Kaitai: Describe the structure of data, not how you read or write it

#42

Post by afranchuk »

jacb wrote: post #17
imtringued wrote: post #13

Earlier quoted context omitted.

It would be a CS breakthrough if it could... You're asking a lot...

I might be missing something - why would this be a breakthrough? It sounds complicated to generate the interfaces, sure, but is there a theoretical problem blocking this, or just practical?

Yeah I was also confused. I wrote a bidirectional parser/writer layer for yaml in a haskell program I had at work. The yaml structure mappings were all declarative in the code and even allowed documentation for the structures to be printed out. It's not that hard once you define the primitive bidirectional (higher-order) mapping function to go from a `Configurable a` to a `Configurable b`, the rest kind of unfolds from there.

Re: Kaitai: Describe the structure of data, not how you read or write it

#43

Post by tprynn »

floppy123 wrote: post #11
carom wrote: post #5

I do love kaitai and recently contributed a grammar, but both the title and the copy talk about writing. > Reading and writing binary formats is hard... Kaitai Struct tries to make this job easier... Kaitai cannot write data back out. [1] This is a major limitation for me. It would be nice to use it as a mutation engine for fuzzing, but without being able to write it back out, it is mostly just beneficial for analysi…

Any other lib that also generates Encoder/Writer code?

BinData (https://github.com/dmendel/bindata) is a Ruby gem for this, basically using a DSL in Ruby to declaratively define binary data formats that can be both read and written.

Re: Kaitai: Describe the structure of data, not how you read or write it

#44

Post by OJFord »

comex wrote: post #22
kevinherron wrote: post #18

Earlier quoted context omitted.

Are we talking about different things? ASN.1 does more or less what I was hoping Kaitai can do. Where's the breakthrough? I just want to be able to describe network protocols in some "language" and generate code that can serialize/deserialize it.

Kaitai is designed to describe arbitrary, preexisting binary formats. You can’t do that with ASN.1.

I think I'm missing something, but rust's `serde`?

Re: Kaitai: Describe the structure of data, not how you read or write it

#45

Post by zoom6628 »

I can s this being hugely useful to bring able to generate code to read wider range of formats instead of having to include/embed dozens of 3rd party libs to read the files. Could be strong tool for commercial product dev that have legal or technical limitation on use of 3rd party code.

Re: Kaitai: Describe the structure of data, not how you read or write it

#49

Post by purpleidea »

ddevault wrote: post #33

This is a use-case for which a DSL is well-suited. They would be wise to abandon YAML.

I think that I agree of you, and I'm obviously fond of clever DSL's cough mgmt config cough, but it's not clear what specifics you had in mind here. Share away if you're interested!

Re: Kaitai: Describe the structure of data, not how you read or write it

#50

Post by touisteur »

floppy123 wrote: post #11
carom wrote: post #5

I do love kaitai and recently contributed a grammar, but both the title and the copy talk about writing. > Reading and writing binary formats is hard... Kaitai Struct tries to make this job easier... Kaitai cannot write data back out. [1] This is a major limitation for me. It would be nice to use it as a mutation engine for fuzzing, but without being able to write it back out, it is mostly just beneficial for analysi…

Any other lib that also generates Encoder/Writer code?

Recordflux?
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