I did something similar for a Computer Security class back in the day, but I did it from userland using dylib injection, and did it as a PoC of the malicious th

I did something similar for a Computer Security class back in the day, but I did it from userland using dylib injection, and did it as a PoC of the malicious things you could do without getting root. Once you've intercepted read() and write(), you control almost everything. One of the demos I did was injecting content into HTTP responses. Fun project, very glad I didn't ever share the code for it :)