On 4/22/21 1:08 AM, Kumar Kartikeya Dwivedi wrote:
On Thu, Apr 22, 2021 at 04:29:28AM IST, Daniel Borkmann wrote:
On 4/20/21 9:37 PM, Kumar Kartikeya Dwivedi wrote:
[...]
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index bec4e6a6e31d..b4ed6a41ea70 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -16,6 +16,8 @@
#include <stdbool.h>
#include <sys/types.h> // for size_t
#include <linux/bpf.h>
+#include <linux/pkt_sched.h>
+#include <linux/tc_act/tc_bpf.h>
#include "libbpf_common.h"
@@ -775,6 +777,48 @@ LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker, const char *filen
LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
+/* Convenience macros for the clsact attach hooks */
+#define BPF_TC_CLSACT_INGRESS TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_INGRESS)
+#define BPF_TC_CLSACT_EGRESS TC_H_MAKE(TC_H_CLSACT, TC_H_MIN_EGRESS)
I would abstract those away into an enum, plus avoid having to pull in
linux/pkt_sched.h and linux/tc_act/tc_bpf.h from main libbpf.h header.
Just add a enum { BPF_TC_DIR_INGRESS, BPF_TC_DIR_EGRESS, } and then the
concrete tc bits (TC_H_MAKE()) can be translated internally.
Ok, will do.
+struct bpf_tc_opts {
+ size_t sz;
Is this set anywhere?
This is needed by the OPTS_* infrastructure.
+ __u32 handle;
+ __u32 class_id;
I'd remove class_id from here as well given in direct-action a BPF prog can
set it if needed.
Ok, makes sense.
+ __u16 priority;
+ bool replace;
+ size_t :0;
What's the rationale for this padding?
dde7b3f5f2f4 ("libbpf: Add explicit padding to bpf_xdp_set_link_opts")
Hm, fair enough.
+};
+
+#define bpf_tc_opts__last_field replace
+
+/* Acts as a handle for an attached filter */
+struct bpf_tc_attach_id {
nit: maybe bpf_tc_ctx
Noted.
+ __u32 handle;
+ __u16 priority;
+};
+
+struct bpf_tc_info {
+ struct bpf_tc_attach_id id;
+ __u16 protocol;
+ __u32 chain_index;
+ __u32 prog_id;
+ __u8 tag[BPF_TAG_SIZE];
+ __u32 class_id;
+ __u32 bpf_flags;
+ __u32 bpf_flags_gen;
Given we do not yet have any setters e.g. for offload, etc, the one thing
I'd see useful and crucial initially is prog_id.
The protocol, chain_index, and I would also include tag should be dropped.
A future user of this API needs to know the tag, so I would like to keep that.
The rest we can drop, and probably document the default values explicitly.
Couldn't this be added along with the future patch for the [future] user?
The tag should be the tag of the prog itself, so if you have prog_id, you
could also retrieve the same tag from the prog. The tag was basically from
the early days where we didn't have bpf_prog_get_info_by_fd().
What does that future user need to do different here?
Thanks,
Daniel
