This adds bpf_program__attach_meta() API to libbpf. Overall it is very
similar to tcx. The API looks as following:
LIBBPF_API struct bpf_link *
bpf_program__attach_meta(const struct bpf_program *prog, int ifindex,
bool peer_device, const struct bpf_meta_opts *opts);
The struct bpf_meta_opts is done in similar way as struct bpf_tcx_opts.
bpf_program__attach_meta() compared to bpf_program__attach_tcx() has one
additional argument, that is peer_device. The latter denotes whether the
program should be attached to the relative peer of ifindex or whether it
should be attached to ifindex itself.
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 16 +++++++++++
tools/lib/bpf/bpf.h | 5 ++++
tools/lib/bpf/libbpf.c | 61 ++++++++++++++++++++++++++++++++++++----
tools/lib/bpf/libbpf.h | 15 ++++++++++
tools/lib/bpf/libbpf.map | 1 +
5 files changed, 92 insertions(+), 6 deletions(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index b0f1913763a3..f1335333b63c 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -810,6 +810,22 @@ int bpf_link_create(int prog_fd, int target_fd,
if (!OPTS_ZEROED(opts, tcx))
return libbpf_err(-EINVAL);
break;
+ case BPF_META_PRIMARY:
+ case BPF_META_PEER:
+ relative_fd = OPTS_GET(opts, meta.relative_fd, 0);
+ relative_id = OPTS_GET(opts, meta.relative_id, 0);
+ if (relative_fd && relative_id)
+ return libbpf_err(-EINVAL);
+ if (relative_id) {
+ attr.link_create.meta.relative_id = relative_id;
+ attr.link_create.flags |= BPF_F_ID;
+ } else {
+ attr.link_create.meta.relative_fd = relative_fd;
+ }
+ attr.link_create.meta.expected_revision = OPTS_GET(opts, meta.expected_revision, 0);
+ if (!OPTS_ZEROED(opts, meta))
+ return libbpf_err(-EINVAL);
+ break;
default:
if (!OPTS_ZEROED(opts, flags))
return libbpf_err(-EINVAL);
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 74c2887cfd24..175cfb95a175 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -415,6 +415,11 @@ struct bpf_link_create_opts {
__u32 relative_id;
__u64 expected_revision;
} tcx;
+ struct {
+ __u32 relative_fd;
+ __u32 relative_id;
+ __u64 expected_revision;
+ } meta;
};
size_t :0;
};
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index b4758e54a815..4d4da8ba2179 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -121,6 +121,8 @@ static const char * const attach_type_name[] = {
[BPF_TCX_INGRESS] = "tcx_ingress",
[BPF_TCX_EGRESS] = "tcx_egress",
[BPF_TRACE_UPROBE_MULTI] = "trace_uprobe_multi",
+ [BPF_META_PRIMARY] = "meta",
+ [BPF_META_PEER] = "meta",
};
static const char * const link_type_name[] = {
@@ -137,6 +139,7 @@ static const char * const link_type_name[] = {
[BPF_LINK_TYPE_NETFILTER] = "netfilter",
[BPF_LINK_TYPE_TCX] = "tcx",
[BPF_LINK_TYPE_UPROBE_MULTI] = "uprobe_multi",
+ [BPF_LINK_TYPE_META] = "meta",
};
static const char * const map_type_name[] = {
@@ -8910,6 +8913,7 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("tc", SCHED_CLS, 0, SEC_NONE), /* deprecated / legacy, use tcx */
SEC_DEF("classifier", SCHED_CLS, 0, SEC_NONE), /* deprecated / legacy, use tcx */
SEC_DEF("action", SCHED_ACT, 0, SEC_NONE), /* deprecated / legacy, use tcx */
+ SEC_DEF("meta", SCHED_CLS, 0, SEC_NONE),
SEC_DEF("tracepoint+", TRACEPOINT, 0, SEC_NONE, attach_tp),
SEC_DEF("tp+", TRACEPOINT, 0, SEC_NONE, attach_tp),
SEC_DEF("raw_tracepoint+", RAW_TRACEPOINT, 0, SEC_NONE, attach_raw_tp),
@@ -12019,11 +12023,11 @@ static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_li
}
static struct bpf_link *
-bpf_program_attach_fd(const struct bpf_program *prog,
- int target_fd, const char *target_name,
- const struct bpf_link_create_opts *opts)
+bpf_program_attach_fd_type(const struct bpf_program *prog,
+ int target_fd, const char *target_name,
+ enum bpf_attach_type attach_type,
+ const struct bpf_link_create_opts *opts)
{
- enum bpf_attach_type attach_type;
char errmsg[STRERR_BUFSIZE];
struct bpf_link *link;
int prog_fd, link_fd;
@@ -12038,8 +12042,6 @@ bpf_program_attach_fd(const struct bpf_program *prog,
if (!link)
return libbpf_err_ptr(-ENOMEM);
link->detach = &bpf_link__detach_fd;
-
- attach_type = bpf_program__expected_attach_type(prog);
link_fd = bpf_link_create(prog_fd, target_fd, attach_type, opts);
if (link_fd < 0) {
link_fd = -errno;
@@ -12053,6 +12055,16 @@ bpf_program_attach_fd(const struct bpf_program *prog,
return link;
}
+static struct bpf_link *
+bpf_program_attach_fd(const struct bpf_program *prog,
+ int target_fd, const char *target_name,
+ const struct bpf_link_create_opts *opts)
+{
+ return bpf_program_attach_fd_type(prog, target_fd, target_name,
+ bpf_program__expected_attach_type(prog),
+ opts);
+}
+
struct bpf_link *
bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd)
{
@@ -12106,6 +12118,43 @@ bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
return bpf_program_attach_fd(prog, ifindex, "tcx", &link_create_opts);
}
+struct bpf_link *
+bpf_program__attach_meta(const struct bpf_program *prog, int ifindex,
+ bool peer_device, const struct bpf_meta_opts *opts)
+{
+ LIBBPF_OPTS(bpf_link_create_opts, link_create_opts);
+ enum bpf_attach_type attach_type;
+ __u32 relative_id;
+ int relative_fd;
+
+ if (!OPTS_VALID(opts, bpf_meta_opts))
+ return libbpf_err_ptr(-EINVAL);
+
+ relative_id = OPTS_GET(opts, relative_id, 0);
+ relative_fd = OPTS_GET(opts, relative_fd, 0);
+ attach_type = peer_device ? BPF_META_PEER : BPF_META_PRIMARY;
+
+ /* validate we don't have unexpected combinations of non-zero fields */
+ if (!ifindex) {
+ pr_warn("prog '%s': target netdevice ifindex cannot be zero\n",
+ prog->name);
+ return libbpf_err_ptr(-EINVAL);
+ }
+ if (relative_fd && relative_id) {
+ pr_warn("prog '%s': relative_fd and relative_id cannot be set at the same time\n",
+ prog->name);
+ return libbpf_err_ptr(-EINVAL);
+ }
+
+ link_create_opts.meta.expected_revision = OPTS_GET(opts, expected_revision, 0);
+ link_create_opts.meta.relative_fd = relative_fd;
+ link_create_opts.meta.relative_id = relative_id;
+ link_create_opts.flags = OPTS_GET(opts, flags, 0);
+
+ return bpf_program_attach_fd_type(prog, ifindex, "meta", attach_type,
+ &link_create_opts);
+}
+
struct bpf_link *bpf_program__attach_freplace(const struct bpf_program *prog,
int target_fd,
const char *attach_func_name)
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 0e52621cba43..827d29cf9a06 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -800,6 +800,21 @@ LIBBPF_API struct bpf_link *
bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
const struct bpf_tcx_opts *opts);
+struct bpf_meta_opts {
+ /* size of this struct, for forward/backward compatibility */
+ size_t sz;
+ __u32 flags;
+ __u32 relative_fd;
+ __u32 relative_id;
+ __u64 expected_revision;
+ size_t :0;
+};
+#define bpf_meta_opts__last_field expected_revision
+
+LIBBPF_API struct bpf_link *
+bpf_program__attach_meta(const struct bpf_program *prog, int ifindex,
+ bool peer_device, const struct bpf_meta_opts *opts);
+
struct bpf_map;
LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 57712321490f..2dd4fe2cba3d 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -397,6 +397,7 @@ LIBBPF_1.3.0 {
bpf_obj_pin_opts;
bpf_object__unpin;
bpf_prog_detach_opts;
+ bpf_program__attach_meta;
bpf_program__attach_netfilter;
bpf_program__attach_tcx;
bpf_program__attach_uprobe_multi;
--
2.34.1
