int restrict_network_interfaces_supported(void) {
_cleanup_(restrict_ifaces_bpf_freep) struct restrict_ifaces_bpf *obj = NULL;
- int r;
static int supported = -1;
+ int r;
if (supported >= 0)
return supported;
r = cg_unified_controller(SYSTEMD_CGROUP_CONTROLLER);
- if (r < 0) {
- log_warning_errno(r, "Can't determine whether the unified hierarchy is used: %m");
- supported = 0;
- return supported;
- }
+ if (r < 0)
+ return log_error_errno(r, "Can't determine whether the unified hierarchy is used: %m");
if (r == 0) {
- log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
- "Not running with unified cgroup hierarchy, BPF is not supported");
- supported = 0;
- return supported;
+ log_debug("Not running with unified cgroup hierarchy, BPF is not supported");
+ return supported = 0;
}
if (dlopen_bpf() < 0)
return false;
if (!sym_bpf_probe_prog_type(BPF_PROG_TYPE_CGROUP_SKB, /*ifindex=*/0)) {
- log_debug_errno(SYNTHETIC_ERRNO(EOPNOTSUPP),
- "BPF program type cgroup_skb is not supported");
- supported = 0;
- return supported;
+ log_debug("BPF program type cgroup_skb is not supported");
+ return supported = 0;
}
r = prepare_restrict_ifaces_bpf(NULL, true, NULL, &obj);
- if (r < 0)
- return log_debug_errno(r, "Failed to load BPF object: %m");
+ if (r < 0) {
+ log_debug_errno(r, "Failed to load BPF object: %m");
+ return supported = 0;
+ }
- supported = bpf_can_link_program(obj->progs.sd_restrictif_i);
- return supported;
+ return supported = bpf_can_link_program(obj->progs.sd_restrictif_i);
}
static int restrict_network_interfaces_install_impl(Unit *u) {