David Ahern <dsah...@kernel.org> writes:
> Add tests to verify ability to add an XDP program to a
> entry in a DEVMAP.
>
> Add negative tests to show DEVMAP programs can not be
> attached to devices as a normal XDP program, and accesses
> to egress_ifindex require BPF_XDP_DEVMAP attach type.
>
> Signed-off-by: David Ahern <dsah...@kernel.org>
> ---
> .../bpf/prog_tests/xdp_devmap_attach.c | 89 +++++++++++++++++++
> .../bpf/progs/test_xdp_devmap_helpers.c | 22 +++++
> .../bpf/progs/test_xdp_with_devmap_helpers.c | 43 +++++++++
> 3 files changed, 154 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c
> create mode 100644
> tools/testing/selftests/bpf/progs/test_xdp_devmap_helpers.c
> create mode 100644
> tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c
> b/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c
> new file mode 100644
> index 000000000000..caeea19f2772
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/xdp_devmap_attach.c
> @@ -0,0 +1,89 @@
> +// SPDX-License-Identifier: GPL-2.0
> +#include <uapi/linux/bpf.h>
> +#include <linux/if_link.h>
> +#include <test_progs.h>
> +
> +#include "test_xdp_devmap_helpers.skel.h"
> +#include "test_xdp_with_devmap_helpers.skel.h"
> +
> +#define IFINDEX_LO 1
> +
> +void test_xdp_with_devmap_helpers(void)
> +{
> + struct test_xdp_with_devmap_helpers *skel;
> + struct bpf_prog_info info = {};
> + struct bpf_devmap_val val = {
> + .ifindex = IFINDEX_LO,
> + };
> + __u32 id, len = sizeof(info);
> + __u32 duration, idx = 0;
> + int err, dm_fd, map_fd;
> +
> +
> + skel = test_xdp_with_devmap_helpers__open_and_load();
> + if (CHECK_FAIL(!skel)) {
> + perror("test_xdp_with_devmap_helpers__open_and_load");
> + return;
> + }
> +
> + /* can not attach program with DEVMAPs that allow programs
> + * as xdp generic
> + */
> + dm_fd = bpf_program__fd(skel->progs.xdp_redir_prog);
> + err = bpf_set_link_xdp_fd(IFINDEX_LO, dm_fd, XDP_FLAGS_SKB_MODE);
> + CHECK(err == 0, "Generic attach of program with 8-byte devmap",
> + "should have failed\n");
> +
> + dm_fd = bpf_program__fd(skel->progs.xdp_dummy_dm);
> + map_fd = bpf_map__fd(skel->maps.dm_ports);
> + err = bpf_obj_get_info_by_fd(dm_fd, &info, &len);
> + if (CHECK_FAIL(err))
> + goto out_close;
> +
> + val.bpf_prog_fd = dm_fd;
> + err = bpf_map_update_elem(map_fd, &idx, &val, 0);
> + CHECK(err, "Add program to devmap entry",
> + "err %d errno %d\n", err, errno);
> +
> + err = bpf_map_lookup_elem(map_fd, &id, &val);
> + CHECK(err, "Read devmap entry", "err %d errno %d\n", err, errno);
> + CHECK(info.id != val.bpf_prog_id, "Expected program id in devmap entry",
> + "expected %u read %u\n", info.id, val.bpf_prog_id);
> +
> + /* can not attach BPF_XDP_DEVMAP program to a device */
> + err = bpf_set_link_xdp_fd(IFINDEX_LO, dm_fd, XDP_FLAGS_SKB_MODE);
> + CHECK(err == 0, "Attach of BPF_XDP_DEVMAP program",
> + "should have failed\n");
> +
> + val.ifindex = 1;
> + val.bpf_prog_fd = bpf_program__fd(skel->progs.xdp_dummy_prog);
> + err = bpf_map_update_elem(map_fd, &idx, &val, 0);
> + CHECK(err == 0, "Add non-BPF_XDP_DEVMAP program to devmap entry",
> + "should have failed\n");
> +
> +out_close:
> + test_xdp_with_devmap_helpers__destroy(skel);
> +}
> +
> +void test_neg_xdp_devmap_helpers(void)
> +{
> + struct test_xdp_devmap_helpers *skel;
> + __u32 duration;
> +
> + skel = test_xdp_devmap_helpers__open_and_load();
> + if (CHECK(skel,
> + "Load of XDP program accessing egress ifindex without attach
> type",
> + "should have failed\n")) {
> + test_xdp_devmap_helpers__destroy(skel);
> + }
> +}
> +
> +
> +void test_xdp_devmap_attach(void)
> +{
> + if (test__start_subtest("DEVMAP with programs in entries"))
> + test_xdp_with_devmap_helpers();
> +
> + if (test__start_subtest("Verifier check of DEVMAP programs"))
> + test_neg_xdp_devmap_helpers();
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_xdp_devmap_helpers.c
> b/tools/testing/selftests/bpf/progs/test_xdp_devmap_helpers.c
> new file mode 100644
> index 000000000000..b360ba2bd441
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_xdp_devmap_helpers.c
> @@ -0,0 +1,22 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* fails to load without expected_attach_type = BPF_XDP_DEVMAP
> + * because of access to egress_ifindex
> + */
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +
> +SEC("xdp_dm_log")
Guess this should be xdp_devmap_log now?
-Toke
