elfredo

elfredo is a library that allows you to patch executables after they were compiled. It utilize an extra embedded section to store data/configurations that one might want to change without recompiling the binary.

There are two main components to any project that uses elfredo: * Customizing your embeditor to mach your datatype (step 1) * Calling the get_embedded_data method to retrieve the embedded data (step 2)

After these two are implemented you end up with two binaries: * [app executable].elf - Your editable app * [embeditor executable].elf - The binary that you use to change the embedded data

Steps to integrate (See ./example): 1. Write your configurable data structure in the embeditor binary: ```rust // myembeditor.rs use elfredo::embeditor::runembeditor; use serde::{Deserialize, Serialize};

[derive(Serialize, Deserialize, Debug)]

pub struct Person { name: String, id: u32, }

fn main() { // This will print the embedded data if exists if let Err(err) = run_embeditor::() { panic!("{}", err); } } ```

1. Read the configurations by using elfredo's api: ```rust // main.rs use elfredo::getembeddeddata; mod myembeditor; use myembeditor::Person;

fn main() -> Result<(), failure::Error> { let person = getembeddeddata::().unwrap(); println!("{:?}", person); Ok(()) }

3. Embed new data to the elf shell john@ubuntu:/mnt/hgfs/elfredo/example$ cat person.json { "name": "Ronald", "id": 5 }

john@ubuntu:/mnt/hgfs/elfredo/example$ cargo run --bin embeditor ../target/debug/example person.json Compiling elfredo v0.1.0 (/mnt/hgfs/elfredo) Compiling example v0.1.0 (/mnt/hgfs/elfredo/example) Finished dev [unoptimized + debuginfo] target(s) in 24.99s Running /mnt/hgfs/elfredo/target/debug/embeditor ../target/debug/example person.json "/tmp/.tmpXh5QHg"

john@ubuntu:/mnt/hgfs/elfredo/example$ ../target/debug/example Person { name: "Ronald", id: 5 } ```