Change FromRawTracepointArgs::arg to return T rather than *const T which
seems to have been returning a dangling pointer.
Arguably this is not strictly necessary; edition 2024 seems to be
focused on increased strictness around unsafe code which doesn't unlock
new functionality for our users. That said, this work revealed an
apparent bug (see above) that we wouldn't otherwise catch due to
allow-by-default lints.
Per man 2 bpf:
> RETURN VALUE
> For a successful call, the return value depends on the operation:
>
> BPF_MAP_CREATE
> The new file descriptor associated with the eBPF map.
>
> BPF_PROG_LOAD
> The new file descriptor associated with the eBPF program.
>
> All other commands
> Zero.
>
> On error, -1 is returned, and errno is set to indicate the error.
Bake this into our syscalls so we stop using `_` so much which can hide
information loss.
And BpfLoader to EbpfLoader.
This also adds type aliases to preserve the use of the old names, making
updating to a new Aya release less of a burden. These aliases are marked
as deprecated since we'll likely remove them in a later release.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Corrent an invalid transmutation for sock_map.
fd is already a ref of MapFd, so transmuting &fd to &SockMapFd is
equivalent to transmuting &&SockMapFd into &SockMapFd which is buggy.
- Adds new `maps_mut()` API to the BpfManager to allow us to iterate though
and pin all of maps at the same time.
- Adds new pin(Path)/unpin(Path) api to Maps so they
can be generically pinned AFTER load.
- Adds macro for pinning explicit map types in aya.
Convert all explicit map types "inner" field to be
pub crate in order to facilitate this.
Signed-off-by: astoycos <astoycos@redhat.com>
`MapData::fd` is now a `MapFd`. This means that `MapData` now closes the
file descriptor on drop. In the future we might consider making `MapFd`
hold a `BorrowedFd` but this requires API design work due to overlapping
borrows.
Since `SockMapFd` is no longer `Copy`, attach methods to take it by
reference to allow callers to use it multiple times as they are
accustomed to doing.
`SockMapFd` implements `try_clone`. `MapFd` and `SockMapFd` are now
returned by reference to allow callers to avoid file descriptor cloning
when desired.
This is an API breaking change.
Updates #612.
This is a breaking change but adds another level of safety to ensure
the file descriptor we receive is valid. Additionally, this allows
aya to internally easily duplicate this file descriptor using std
library methods instead of manually calling `dup` which doesn't
duplicate with the CLOSE_ON_EXEC flag that is standard pratice to
avoid leaking the file descriptor when exec'ing.
Notably:
- clippy::use_self: replaced many T with Self.
- single_use_lifetimes: removed some single use lifetimes.
- unreachable_pub: removed some unreachable pub items.
- unused_crate_dependencies: removed unused futures,parking_lot deps.
- unused_qualifications: found a potential `crate` vs `$crate` bug.
- let_underscore_drop: not enabled, seems to trigger false positives.
- missing_copy_implementations: not enabled, unclear if we want this.
- unsafe_op_in_unsafe_fn: not enabled, unclear if we want this.
- unused_results: not enabled, needs many fixes (but I think wanted).
The primary driver of change here is that `MapData::create` is now a
factory function that returns `Result<Self, _>` rather than mutating
`&mut self`. The remaining changes are consequences of that change, the
most notable of which is the removal of several errors which are no
longer possible.
This is just taking https://github.com/aya-rs/aya/pull/633 to its
logical conclusion. Because `std::os::fd` was only introduced as a
module in Rust v1.66.0 I have also updated the `Cargo.toml` of the
`aya` package to reflect the true MSRV. Note that this commit is *not*
the cause for this MSRV bump, that was done by a previous commit, this
commit is just making it explicit in the `Cargo.toml`
Fix some broken rust doc links.
Make sure rustdoc build fail on warnings
so we catch these broken links in CI.
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
switch map() and map_mut() from returning a
`Result` to an `Option` since it's just getting
a value from a Hashmap, and to stay in line with
the Programs API.
Remove `MapError::MapNotFound`
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
Respond to more review comments:
Revert to try_from in doctests so we don't need
to explicitly specify type parameters.
Fixup some documentation
Remove explit types in `try_from` methods
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
Create a new type called `SockMapFd` which is
solely used when a program needs to attach
to a socket map. In the future this same
tatic could be used for other use cases
so we may make this more generic.
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
Build completing tests passing
Refactor the Map API to better align
with the aya programs API. Specifically
remove all internal locking mechanisms
and custom Deref/DerefMut implementations.
They are replaced with a Map enum
and AsRef/AsMut implementations.
All Try_From implementations have been moved
to standardized enums, with a slightly
special one for PerfEventArray's.
Also cleanup/fix all associated tests and
documentation.
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
Add `from_pinned` to allow loading BPF maps
from pinned points in the bpffs and
`from_fd` to allow loading BPF maps from
RawFds aquired via some other means eg
a unix socket.
These functions return an
aya::Map which has not been used previously
but will be the future abstraction once
all bpf maps are represented as an enum.
Signed-off-by: Andrew Stoycos <astoycos@redhat.com>
This commit allows for BTF maps in the .maps ELF section to be parsed.
It reads the necessary information from the BTF section of the ELF file.
While the btf_ids of Keys and Values types are stored, they are not (yet)
used.
When creating a BTF map, we pass the btf_key_type_id and
btf_value_type_id.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
bpf_map_update_elem is used in lieu of bpf_map_push_elem to maintain support for kernel version < 4.20. The kernel expects a null pointer for the key for this use case. With this change, if you pass None as key to `bpf_map_update_elem`, it will pass null as key.
Map iteration can yield stale keys and values by virtue of sharing a
data structure with BPF programs which can modify it. However, all
accesses remain perfectly safe and will not cause memory corruption or
data races.
Map and ProgramData objects had unnecessarily cloned strings for their
names, despite them being just as easily available to external users via
bpf.maps() and bpf.programs().
This commit adds 2 new methods to aya::sys
- bpf_pin_object
- bpf_get_object
Which allow the pinning and retrieval of programs/maps to bpffs.
It adds a `Program.pin` API, such that a loaded program can be pinned.
For map pinning, the user must ensure the `pinning u32` in the
`bpf_map_def` is set to 1, maps will be pinned using a new builder API.
BpfLoader::new().map_pin_path("/sys/fs/bpf/myapp").load_file("myapp.o")
This will pin all maps whose definition requests pinning to path + name.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>