selftests/bpf: Add byte swapping selftest

// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2020 Facebook */

#include <test_progs.h>

#include "test_endian.skel.h"

static int duration;

#define IN16 0x1234

#define IN32 0x12345678U

#define IN64 0x123456789abcdef0ULL

#define OUT16 0x3412

#define OUT32 0x78563412U

#define OUT64 0xf0debc9a78563412ULL

void test_endian(void)

{

	struct test_endian* skel;

	struct test_endian__bss *bss;

	int err;

	skel = test_endian__open_and_load();

	if (CHECK(!skel, "skel_open", "failed to open skeleton\n"))

		return;

	bss = skel->bss;

	bss->in16 = IN16;

	bss->in32 = IN32;

	bss->in64 = IN64;

	err = test_endian__attach(skel);

	if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))

		goto cleanup;

	usleep(1);

	CHECK(bss->out16 != OUT16, "out16", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->out16, (__u64)OUT16);

	CHECK(bss->out32 != OUT32, "out32", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->out32, (__u64)OUT32);

	CHECK(bss->out64 != OUT64, "out16", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->out64, (__u64)OUT64);

	CHECK(bss->const16 != OUT16, "const16", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->const16, (__u64)OUT16);

	CHECK(bss->const32 != OUT32, "const32", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->const32, (__u64)OUT32);

	CHECK(bss->const64 != OUT64, "const64", "got 0x%llx != exp 0x%llx\n",

	      (__u64)bss->const64, (__u64)OUT64);

cleanup:

	test_endian__destroy(skel);

}

// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2020 Facebook */

#include "vmlinux.h"

#include <bpf/bpf_helpers.h>

#include <bpf/bpf_endian.h>

#define IN16 0x1234

#define IN32 0x12345678U

#define IN64 0x123456789abcdef0ULL

__u16 in16 = 0;

__u32 in32 = 0;

__u64 in64 = 0;

__u16 out16 = 0;

__u32 out32 = 0;

__u64 out64 = 0;

__u16 const16 = 0;

__u32 const32 = 0;

__u64 const64 = 0;

SEC("raw_tp/sys_enter")

int sys_enter(const void *ctx)

{

	out16 = __builtin_bswap16(in16);

	out32 = __builtin_bswap32(in32);

	out64 = __builtin_bswap64(in64);

	const16 = ___bpf_swab16(IN16);

	const32 = ___bpf_swab32(IN32);

	const64 = ___bpf_swab64(IN64);

	return 0;

}

char _license[] SEC("license") = "GPL";