fishhook

fishhook-rs

A Rust port of fishhook — a library that enables dynamically rebinding symbols in Mach-O binaries at runtime. Useful for intercepting system functions like malloc, free, or open on Apple platforms.

Platform support: Currently tested only on macOS (aarch64-apple-darwin)

Installation

Add to your Cargo.toml:

[dependencies]
fishhook = "0.1"

Usage

Example below uses ctor for invoking init() first

use fishhook::{register, Rebinding};

#[ctor::ctor]
fn init() {
    unsafe {
        register(vec![
            Rebinding {
                name: "malloc".to_string(),
                function: my_malloc as *const c_void,
            },
            Rebinding {
                name: "calloc".to_string(),
                function: my_calloc as *const c_void,
            },
            Rebinding {
                name: "realloc".to_string(),
                function: my_realloc as *const c_void,
            },
            Rebinding {
                name: "free".to_string(),
                function: my_free as *const c_void,
            },
            Rebinding {
                name: "atexit".to_string(),
                function: my_exit as *const c_void,
            },
        ]);
    }
}

License: MIT