linux/tools/testing/selftests/bpf/progs/test_skb_ctx.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/bpf.h>
#include "bpf_helpers.h"

int _version SEC("version") = 1;
char _license[] SEC("license") = "GPL";

SEC("skb_ctx")
int process(struct __sk_buff *skb)
{
	#pragma clang loop unroll(full)
	for (int i = 0; i < 5; i++) {
		if (skb->cb[i] != i + 1)
			return 1;
		skb->cb[i]++;
	}
	skb->priority++;

	return 0;
}
selftests: bpf: add selftest for __sk_buff context in BPF_PROG_TEST_RUN Simple test that sets cb to {1,2,3,4,5} and priority to 6, runs bpf program that fails if cb is not what we expect and increments cb[i] and priority. When the test finishes, we check that cb is now {2,3,4,5,6} and priority is 7. We also test the sanity checks: * ctx_in is provided, but ctx_size_in is zero (same for ctx_out/ctx_size_out) * unexpected non-zero fields in __sk_buff return EINVAL Signed-off-by: Stanislav Fomichev <sdf@google.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> 2019-04-09 11:49:11 -07:00			`// SPDX-License-Identifier: GPL-2.0`

			`#include <linux/bpf.h>`
			`#include "bpf_helpers.h"`

			`int _version SEC("version") = 1;`
			`char _license[] SEC("license") = "GPL";`

			`SEC("skb_ctx")`
			`int process(struct __sk_buff *skb)`
			`{`
			`#pragma clang loop unroll(full)`
			`for (int i = 0; i < 5; i++) {`
			`if (skb->cb[i] != i + 1)`
			`return 1;`
			`skb->cb[i]++;`
			`}`
			`skb->priority++;`

			`return 0;`
			`}`