BPF iterators[0] are a way to dump kernel data into user-space and an
alternative to `/proc` filesystem.
This change adds support for BPF iterators on the user-space side. It
provides a possibility to retrieve the outputs of BPF iterator programs
both from sync and async Rust code.
[0] https://docs.kernel.org/bpf/bpf_iterators.html
Users have reported issues with programs failing the verifier when they
are attempting to read or write to variables that the compiler places in
the .bss section. Add a test that places variables in each section and
exercises read and write operations on them.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
This commit adds the initial support for TCX
bpf links. This is a new, multi-program, attachment
type allows for the caller to specify where
they would like to be attached relative to other
programs at the attachment point using the LinkOrder
type.
Signed-off-by: astoycos <astoycos@redhat.com>
Co-authored-by: Andre Fredette <afredette@redhat.com>
Co-authored-by: Dave Tucker <dave@dtucker.co.uk>
Co-authored-by: Tamir Duberstein <tamird@gmail.com>
Improves the existing integraiton tests for `loaded_programs()` and
`loaded_maps()` in consideration for older kernels:
- Opt for `SocketFilter` program in tests since XDP requires v4.8 and
fragments requires v5.18.
- For assertion tests, first perform the assertion, if the assertion
fails, then it checks the host kernel version to see if it is above
the minimum version requirement. If not, then continue with test,
otherwise fail.
For assertions that are skipped, they're logged in stderr which can
be observed with `-- --nocapture`.
This also fixes the `bpf_prog_get_info_by_fd()` call for kernels below
v4.15. If calling syscall on kernels below v4.15, it can produce an
`E2BIG` error because `check_uarg_tail_zero()` expects the entire
struct to all-zero bytes (which is caused from the map info).
Instead, we first attempt the syscall with the map info filled, if it
returns `E2BIG`, then perform syscall again with empty closure.
Also adds doc for which version a kernel feature was introduced for
better awareness.
The tests have been verified kernel versions:
- 4.13.0
- 4.15.0
- 6.1.0
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>
Move the use of clang and llvm-objcopy from run-time to build-time. This
allows the integration tests to run on VMs with simpler userlands.
Create a new CI job to build the integration tests separately from
running them. Ship them from that job to the runner job using github
actions artifacts.
For tests that do networking operations, this allows to have a
clean-state network namespace and interfaces for each test. Mainly, this
avoids "device or resource busy" errors when reusing the loopback
interface across tests.
"integration tests" as defined by Cargo produce a binary per file in the
tests directory. This is really not what we want and has a number of
downsides, but the main one is binary size.
Before:
tamird@pc:~/src/aya$ cargo xtask build-integration-test | xargs ls -lah
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `target/debug/xtask build-integration-test`
Compiling integration-test v0.1.0 (/home/tamird/src/aya/test/integration-test)
Finished dev [unoptimized + debuginfo] target(s) in 0.68s
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/bpf_probe_read-e03eb905a5e6209c
-rwxrwxr-x 1 tamird tamird 35M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/btf_relocations-57a4fbb38bf06064
-rwxrwxr-x 1 tamird tamird 31M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/elf-98b7a32d6d04effb
-rwxrwxr-x 1 tamird tamird 6.9M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/integration_test-0dd55ce96bfdad77
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/load-0718562e85b86d03
-rwxrwxr-x 1 tamird tamird 40M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/log-dbf355f9ea34068a
-rwxrwxr-x 1 tamird tamird 36M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/rbpf-89a1bb848fa5cc3c
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/relocations-cfe655c3bb413d8b
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/smoke-ccd3974180a3fd29
After:
tamird@pc:~/src/aya$ cargo xtask build-integration-test | xargs ls -lah
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `target/debug/xtask build-integration-test`
Compiling integration-test v0.1.0 (/home/tamird/src/aya/test/integration-test)
Finished dev [unoptimized + debuginfo] target(s) in 0.90s
-rwxrwxr-x 1 tamird tamird 47M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/integration_test-0dd55ce96bfdad77
Since we plan to run these tests in a VM, copying 10x fewer bytes seems
like a win.
- Add libbpf as a submodule. This prevents having to plumb its location
around (which can't be passed to Cargo build scripts) and also
controls the version against which codegen has run.
- Move bpf written in C to the integration-test crate and define
constants for each probe.
- Remove magic; each C source file must be directly enumerated in the
build script and in lib.rs.
This doesn't add any value; use `cargo build --tests` with
`--message-format=json` instead; parse the output using `cargo_metadata`
to discover the location of the test binary.
Move test/integration-test/src/tests -> test/integration-test/tests to
conform to
https://doc.rust-lang.org/book/ch11-03-test-organization.html#integration-tests.
Michal Rostecki
Tamir Duberstein
Dave Tucker
astoycos
tyrone-wu
Wouter Dullaert
Andrew Werner
Tuetuopay