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>
This change exposes the BPF helper bpf_socket_get_uid as a public method
of SkBuffContext, which allows to get the owner UID of the socket
associated to the sk_buff stored in the context.
Signed-off-by: Michal Rostecki <vadorovsky@gmail.com>
fentry and fexit programs are similar to kprobe and kretprobe, but they
are newer and they have practically zero overhead to call before or
after kernel function. Also, fexit programs are focused on access to
arguments rather than the return value.
Those kind of programs were introduced in the following patchset:
https://lwn.net/Articles/804112/
Signed-off-by: Michal Rostecki <mrostecki@opensuse.org>
This is necessary since the context is used in many other program types
and not just in SK_SKB programs.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
This change adds support for the following program types:
* raw tracepoint
* LSM
Supporting LSM programs involved a necessity of supporting more
load_attrs for the BPF_PROG_LOAD operation, concretely:
* expected_attach_type - for LSM programs, it has always to be set to
BPF_LSM_MAC
* attach_btf_obj_fd - it's often used to reference the file descriptor of
program's BTF info, altough in case of LSM programs, it only has to
contain the value 0, which means the vmlinux object file (usually
/sys/kernel/btf/vmlinux)
* attach_btf_id - ID of the BTF object, which in case of LSM programs is
the ID of the function (the LSM hook)
The example of LSM program using that functionality can be found here:
https://github.com/vadorovsky/aya-example-lsmFixes: #9
Signed-off-by: William Findlay <william@williamfindlay.com>
Signed-off-by: Michal Rostecki <mrostecki@opensuse.org>