Implement tc BPF link support for libbpf. The bpf_program__attach_fd()
API has been refactored slightly in order to pass bpf_link_create_opts.
A new bpf_program__attach_tc() has been added on top of this which allows
for passing ifindex and prio parameters.
New sections are tc/ingress and tc/egress which map to BPF_NET_INGRESS
and BPF_NET_EGRESS, respectively.
Co-developed-by: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>
Signed-off-by: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
---
tools/lib/bpf/bpf.c | 4 ++++
tools/lib/bpf/bpf.h | 3 +++
tools/lib/bpf/libbpf.c | 31 ++++++++++++++++++++++++++-----
tools/lib/bpf/libbpf.h | 2 ++
tools/lib/bpf/libbpf.map | 1 +
5 files changed, 36 insertions(+), 5 deletions(-)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index d1e338ac9a62..f73fdecbb5f8 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -752,6 +752,10 @@ int bpf_link_create(int prog_fd, int target_fd,
if (!OPTS_ZEROED(opts, tracing))
return libbpf_err(-EINVAL);
break;
+ case BPF_NET_INGRESS:
+ case BPF_NET_EGRESS:
+ attr.link_create.tc.priority = OPTS_GET(opts, tc.priority, 0);
+ 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 96de58fecdbc..937583421327 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -334,6 +334,9 @@ struct bpf_link_create_opts {
struct {
__u64 cookie;
} tracing;
+ struct {
+ __u32 priority;
+ } tc;
};
size_t :0;
};
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 184ce1684dcd..6eb33e4324ad 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8474,6 +8474,8 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("kretsyscall+", KPROBE, 0, SEC_NONE, attach_ksyscall),
SEC_DEF("usdt+", KPROBE, 0, SEC_NONE, attach_usdt),
SEC_DEF("tc", SCHED_CLS, 0, SEC_NONE),
+ SEC_DEF("tc/ingress", SCHED_CLS, BPF_NET_INGRESS, SEC_ATTACHABLE_OPT),
+ SEC_DEF("tc/egress", SCHED_CLS, BPF_NET_EGRESS, SEC_ATTACHABLE_OPT),
SEC_DEF("classifier", SCHED_CLS, 0, SEC_NONE),
SEC_DEF("action", SCHED_ACT, 0, SEC_NONE),
SEC_DEF("tracepoint+", TRACEPOINT, 0, SEC_NONE, attach_tp),
@@ -11238,11 +11240,10 @@ 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, int btf_id,
- const char *target_name)
+bpf_program__attach_fd_opts(const struct bpf_program *prog,
+ const struct bpf_link_create_opts *opts,
+ int target_fd, const char *target_name)
{
- DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts,
- .target_btf_id = btf_id);
enum bpf_attach_type attach_type;
char errmsg[STRERR_BUFSIZE];
struct bpf_link *link;
@@ -11260,7 +11261,7 @@ bpf_program__attach_fd(const struct bpf_program *prog, int target_fd, int btf_id
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);
+ link_fd = bpf_link_create(prog_fd, target_fd, attach_type, opts);
if (link_fd < 0) {
link_fd = -errno;
free(link);
@@ -11273,6 +11274,16 @@ bpf_program__attach_fd(const struct bpf_program *prog, int target_fd, int btf_id
return link;
}
+static struct bpf_link *
+bpf_program__attach_fd(const struct bpf_program *prog, int target_fd, int btf_id,
+ const char *target_name)
+{
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts,
+ .target_btf_id = btf_id);
+
+ return bpf_program__attach_fd_opts(prog, &opts, target_fd, target_name);
+}
+
struct bpf_link *
bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd)
{
@@ -11291,6 +11302,16 @@ struct bpf_link *bpf_program__attach_xdp(const struct bpf_program *prog, int ifi
return bpf_program__attach_fd(prog, ifindex, 0, "xdp");
}
+struct bpf_link *bpf_program__attach_tc(const struct bpf_program *prog,
+ int ifindex, __u32 priority)
+{
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts,
+ .tc.priority = priority);
+
+ /* target_fd/target_ifindex use the same field in LINK_CREATE */
+ return bpf_program__attach_fd_opts(prog, &opts, ifindex, "tc");
+}
+
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 eee883f007f9..7e64cec9a1ba 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -645,6 +645,8 @@ bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
LIBBPF_API struct bpf_link *
bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
LIBBPF_API struct bpf_link *
+bpf_program__attach_tc(const struct bpf_program *prog, int ifindex, __u32 priority);
+LIBBPF_API 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.map b/tools/lib/bpf/libbpf.map
index 0c94b4862ebb..473ed71829c6 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -378,4 +378,5 @@ LIBBPF_1.1.0 {
user_ring_buffer__reserve_blocking;
user_ring_buffer__submit;
bpf_prog_detach_opts;
+ bpf_program__attach_tc;
} LIBBPF_1.0.0;
--
2.34.1
