@@ -21,18 +21,32 @@
static int ifindex;
static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
static __u32 prog_id;
+static bool egress;
static void int_exit(int sig)
{
+ struct bpf_xdp_set_link_opts opts = { .sz = sizeof(opts) };
__u32 curr_prog_id = 0;
+ int err, old_fd;
- if (bpf_get_link_xdp_id(ifindex, &curr_prog_id, xdp_flags)) {
+ if (egress)
+ err = bpf_get_link_xdp_egress_id(ifindex, &curr_prog_id,
+ xdp_flags);
+ else
+ err = bpf_get_link_xdp_id(ifindex, &curr_prog_id, xdp_flags);
+ if (err) {
printf("bpf_get_link_xdp_id failed\n");
exit(1);
}
- if (prog_id == curr_prog_id)
- bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
- else if (!curr_prog_id)
+ if (prog_id == curr_prog_id) {
+ if (egress)
+ opts.egress = 1;
+
+ old_fd = bpf_prog_get_fd_by_id(prog_id);
+ opts.old_fd = old_fd;
+ bpf_set_link_xdp_fd_opts(ifindex, -1, xdp_flags, &opts);
+ close(old_fd);
+ } else if (!curr_prog_id)
printf("couldn't find a prog id on a given interface\n");
else
printf("program on interface changed, not removing\n");
@@ -73,19 +87,21 @@ static void usage(const char *prog)
"OPTS:\n"
" -S use skb-mode\n"
" -N enforce native mode\n"
- " -F force loading prog\n",
+ " -F force loading prog\n"
+ " -E egress path program\n",
prog);
}
int main(int argc, char **argv)
{
+ struct bpf_xdp_set_link_opts opts = { .sz = sizeof(opts) };
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
struct bpf_prog_load_attr prog_load_attr = {
.prog_type = BPF_PROG_TYPE_XDP,
};
struct bpf_prog_info info = {};
__u32 info_len = sizeof(info);
- const char *optstr = "FSN";
+ const char *optstr = "FSNE";
int prog_fd, map_fd, opt;
struct bpf_object *obj;
struct bpf_map *map;
@@ -103,6 +119,9 @@ int main(int argc, char **argv)
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
break;
+ case 'E':
+ egress = true;
+ break;
default:
usage(basename(argv[0]));
return 1;
@@ -130,6 +149,10 @@ int main(int argc, char **argv)
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;
+ if (egress) {
+ opts.egress = 1;
+ prog_load_attr.expected_attach_type = BPF_XDP_EGRESS;
+ }
if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
return 1;
@@ -149,7 +172,8 @@ int main(int argc, char **argv)
signal(SIGINT, int_exit);
signal(SIGTERM, int_exit);
- if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
+ err = bpf_set_link_xdp_fd_opts(ifindex, prog_fd, xdp_flags, &opts);
+ if (err < 0) {
printf("link set xdp fd failed\n");
return 1;
}