In-depth: ELF - The Extensible & Linkable Format

ELF files are everywhere: From your PS4, to the Wii, to any Linux device out there. In this video we explore the Extensible & Linkable Format, and understand how it works - on the byte level! Errata: - At the beginning I say extensible while displaying executable and linkable file format - Extensible is the old name, nowadays ist called Executable. Must’ve gotten confused :) Further reading: - The ELF specification: refspecs.linuxfoundation.org/elf/elf.pdf - elf.h from the Linux kernel: elixir.bootlin.com/linux/latest/source/include/uap… - How programs get run: lwn.net/Articles/631631/ - TLS: docs.oracle.com/cd/E19120-01/open.solaris/819-0690… - Relocation: refspecs.linuxbase.org/elf/gabi4+/ch4.reloc.html - sstrip: github.com/BR903/ELFkickers/ Timestamps: 0:00 Intro 0:47 segment and section differentiation 2:05 ELF structure 3:39 ELF header data structure 9:34 Program header data structure 13:54 Section header data structure

• #science_technology
• #elf
• #hacking
• #reverse_engineering
• #ghidra
• #extensible_linkable_format
• #executables
• #programming