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 <dsahern@xxxxxxxxxx>
---
.../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")
+int xdpdm_devlog(struct xdp_md *ctx)
+{
+ char fmt[] = "devmap redirect: dev %u -> dev %u len %u\n";
+ void *data_end = (void *)(long)ctx->data_end;
+ void *data = (void *)(long)ctx->data;
+ unsigned int len = data_end - data;
+
+ bpf_trace_printk(fmt, sizeof(fmt),
+ ctx->ingress_ifindex, ctx->egress_ifindex, len);
+
+ return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c b/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
new file mode 100644
index 000000000000..645f7f415857
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_xdp_with_devmap_helpers.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+struct {
+ __uint(type, BPF_MAP_TYPE_DEVMAP);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(struct bpf_devmap_val));
+ __uint(max_entries, 4);
+} dm_ports SEC(".maps");
+
+SEC("xdp_redir")
+int xdp_redir_prog(struct xdp_md *ctx)
+{
+ return bpf_redirect_map(&dm_ports, 1, 0);
+}
+
+/* invalid program on DEVMAP entry;
+ * SEC name means expected attach type not set
+ */
+SEC("xdp_dummy")
+int xdp_dummy_prog(struct xdp_md *ctx)
+{
+ return XDP_PASS;
+}
+
+/* valid program on DEVMAP entry via SEC name;
+ * has access to egress and ingress ifindex
+ */
+SEC("xdp_devmap")
+int xdp_dummy_dm(struct xdp_md *ctx)
+{
+ char fmt[] = "devmap redirect: dev %u -> dev %u len %u\n";
+ void *data_end = (void *)(long)ctx->data_end;
+ void *data = (void *)(long)ctx->data;
+ unsigned int len = data_end - data;
+
+ bpf_trace_printk(fmt, sizeof(fmt),
+ ctx->ingress_ifindex, ctx->egress_ifindex, len);
+
+ return XDP_PASS;
+}
--
2.21.1 (Apple Git-122.3)
