```
error: field `0` is never read
--> bpf/aya-bpf/src/helpers.rs:737:22
|
737 | pub struct PrintkArg(u64);
| --------- ^^^
| |
| field in this struct
|
= note: `PrintkArg` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
= note: `-D dead-code` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(dead_code)]`
help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
|
737 | pub struct PrintkArg(());
| ~~
```
See https://github.com/rust-lang/rust/issues/119659.
This implements the userspace binding for RingBuf.
Instead of streaming the samples as heap buffers, the process_ring
function takes a callback to which we pass the event's byte region,
roughly following [libbpf]'s API design. This avoids a copy and allows
marking the consumer pointer in a timely manner.
[libbpf]: https://github.com/libbpf/libbpf/blob/master/src/ringbuf.c
Additionally, integration tests are added to demonstrate the usage
of the new APIs and to ensure that they work end-to-end.
Co-authored-by: William Findlay <william@williamfindlay.com>
Co-authored-by: Tatsuyuki Ishi <ishitatsuyuki@gmail.com>
The implementation changed since the original commit was written, and
some mistakes went in:
- missing bpf_redirect_map wrapper
- extra bpf_map_lookup_elem on maps for which it is forbidden
This feature is equivalent to async_tokio || async_std; removing it
avoids warnings emitted during `cargo hack check --feature-powerset`
where async is selected without either of the other features.
Use cargo hack to ensure clippy runs on the powerset of features.
Replace all `assert!(matches!(..))` with `assert_matches!(..)`.
Remove the now-unused build-integration-test xtask command whose logic
doesn't match that of the build-and-run command.
This change does a few things:
- it fixes a bug in the wrappers, where we were expecting the kernel to
return len=1 for b"\0" where it instead returns 0 and doesn't write
out the NULL terminator
- it makes the helpers more robust by hardcoding bound checks in
assembly so that LLVM optimizations can't transform the checks in a
way that the verifier can't understand.
- it adds integration tests
This patch introduces `pt_regs` handling in aya-bpf/args.rs
for the riscv64 architecture. The current CI is disabled
for riscv64 because this implementation is missing.
Such an assignment in two parts (first deref in `unsafe`, then field
access outside of `unsafe`) is bogus: the deref "returned" by the
`unsafe` block actually creates a copy of the `__sk_buff` struct because
it implements `Copy`. The mark value is written to the `mark` field of
the copy, and not the real `__sk_buff`.
Change it to do it all in the `unsafe` block.
The same is done for the `.len()` getter to avoid copying the whole
`__sk_buff` struct for a 32 bit field. Although such a copy should be
optimized out by the compiler, it's better to help it do so.
Kernel 4.15 added a new eBPF program that can
be used with cgroup v2 to control & observe device
access (e.g. read, write, mknod) - `BPF_PROG_TYPE_CGROUP_DEVICE`.
We add the ability to create these programs with the `cgroup_device`
proc macro which creates the `cgroup/dev` link section. Device
details are available to the eBPF program in `DeviceContext`.
The userspace representation is provided with the `CgroupDevice`
structure.
Fixes: #212
Signed-off-by: Milan <milan@mdaverde.com>
This change separates the previous `SkBuffContext` into three structs:
* `SkBuff` which is a wrapper around `__sk_buff` which contains all
possible methods operating on it.
* `SkBuffContext` which is a program context for programs which
**cannot** access `__sk_buff` directly and instead can only use
`load_bytes`.
* `TcContext` which is a classifier context which can access `__sk_buff`
directly, hence exposes `data` and `data_end`.
Signed-off-by: Michal Rostecki <vadorovsky@gmail.com>
The pull_data method is used to ensure that all the required bytes
are available in the linear portion of the skb.
Signed-off-by: Hengqi Chen <chenhengqi@outlook.com>
The `bpf_printk!` macro is a helper providing a convenient way to invoke the
`bpf_trace_printk` and `bpf_trace_vprintk` BPF helpers. It is implemented as
a macro because it requires variadic arguments.
Change it from `[i8; 16]` to `[u8; 18]`. `i8` arrays cannot be easily used in
Rust for converting to string (i.e. with `core::str::from_utf8_unchecked`)
and developers have to convert them themselves with unsafe code.
Using u8 arrays lets developers to just convert it with
`core::str::from_utf8_unchecked` without any limitations.
Example:
https://github.com/vadorovsky/aya-examples/blob/main/clone/clone-ebpf/src/main.rs
Signed-off-by: Michal Rostecki <vadorovsky@gmail.com>
This change adds two new helpers:
* bpf_probe_read_user_str_bytes
* bpf_probe_read_kernel_str_bytes
Those new helpers are returning a bytes slice (`&[u8]`) with a length
equal to the length of probed, null-terminated string. When using those
helpers, users don't have to manually check for length and create such
slices themselves. They also make converting to `str` way more
convenient, for example:
```rust
let my_str = unsafe {
core::str::from_utf8_unchecked(
bpf_probe_read_user_str_bytes(user_ptr, &mut buf)?
)
};
```
This change also deprecates the old helpers, since their names are
confusing (they have nothing to do with Rust `str`) and using them
requires writing boilerplate code (for checking the length and making
eBPF verifier happy):
* bpf_probe_read_user_str
* bpf_probe_read_kernel_str
Tested on:
516b29af68
Signed-off-by: Michal Rostecki <vadorovsky@gmail.com>