Tamir Duberstein
2c927581fe
Pass the kernel attach type into the shared loader from each typed
wrapper instead of storing a second mutable copy in `ProgramData`.
This removes the from_pin repair pattern, avoids stale shadow state, and
keeps attach paths driven by wrapper-owned typed attach metadata or
fixed constants.
Also simplify `{sk,cgroup}_skb` section parsing by representing all
variants as `ProgramSection::SkSkb { kind }` and
`ProgramSection::CgroupSkb { attach_type }` respectively, with the
attach type enums shared from aya-obj.
aya-obj
Status
This crate includes code that started as internal API used by the aya crate. It has been split out so that it can be used by other projects that deal with eBPF object files. Unless you're writing low level eBPF plumbing tools, you should not need to use this crate but see the aya crate instead.
The API as it is today has a few rough edges and is generally not as polished nor stable as the main aya crate API. As always, improvements welcome!
Overview
eBPF programs written with libbpf or aya-bpf are usually compiled into an ELF object file, using various sections to store information about the eBPF programs.
aya-obj is a library for parsing such eBPF object files, with BTF and
relocation support.
Example
This example loads a simple eBPF program and runs it with rbpf.
use aya_obj::{generated::bpf_insn, Object};
// Parse the object file
let bytes = std::fs::read("program.o").unwrap();
let mut object = Object::parse(&bytes).unwrap();
// Relocate the programs
object.relocate_calls().unwrap();
object.relocate_maps(std::iter::empty()).unwrap();
// Run with rbpf
let instructions = &object.programs["prog_name"].function.instructions;
let data = unsafe {
core::slice::from_raw_parts(
instructions.as_ptr() as *const u8,
instructions.len() * core::mem::size_of::<bpf_insn>(),
)
};
let vm = rbpf::EbpfVmNoData::new(Some(data)).unwrap();
let _return = vm.execute_program().unwrap();