extern const struct bpf_func_proto bpf_sock_hash_update_proto;
extern const struct bpf_func_proto bpf_get_current_cgroup_id_proto;
+extern const struct bpf_func_proto bpf_get_local_storage_proto;
+
/* Shared helpers among cBPF and eBPF. */
void bpf_user_rnd_init_once(void);
u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
* Return
* A 64-bit integer containing the current cgroup id based
* on the cgroup within which the current task is running.
+ *
+ * void* get_local_storage(void *map, u64 flags)
+ * Description
+ * Get the pointer to the local storage area.
+ * The type and the size of the local storage is defined
+ * by the *map* argument.
+ * The *flags* meaning is specific for each map type,
+ * and has to be 0 for cgroup local storage.
+ *
+ * Depending on the bpf program type, a local storage area
+ * can be shared between multiple instances of the bpf program,
+ * running simultaneously.
+ *
+ * A user should care about the synchronization by himself.
+ * For example, by using the BPF_STX_XADD instruction to alter
+ * the shared data.
+ * Return
+ * Pointer to the local storage area.
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
FN(rc_repeat), \
FN(rc_keydown), \
FN(skb_cgroup_id), \
- FN(get_current_cgroup_id),
+ FN(get_current_cgroup_id), \
+ FN(get_local_storage),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
return &bpf_map_delete_elem_proto;
case BPF_FUNC_get_current_uid_gid:
return &bpf_get_current_uid_gid_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
case BPF_FUNC_trace_printk:
if (capable(CAP_SYS_ADMIN))
return bpf_get_trace_printk_proto();
const struct bpf_func_proto bpf_sock_map_update_proto __weak;
const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak;
+const struct bpf_func_proto bpf_get_local_storage_proto __weak;
const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void)
{
.gpl_only = false,
.ret_type = RET_INTEGER,
};
+
+DECLARE_PER_CPU(void*, bpf_cgroup_storage);
+
+BPF_CALL_2(bpf_get_local_storage, struct bpf_map *, map, u64, flags)
+{
+ /* map and flags arguments are not used now,
+ * but provide an ability to extend the API
+ * for other types of local storages.
+ * verifier checks that their values are correct.
+ */
+ return (unsigned long) this_cpu_read(bpf_cgroup_storage);
+}
+
+const struct bpf_func_proto bpf_get_local_storage_proto = {
+ .func = bpf_get_local_storage,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_ANYTHING,
+};
#endif
func_id != BPF_FUNC_current_task_under_cgroup)
goto error;
break;
+ case BPF_MAP_TYPE_CGROUP_STORAGE:
+ if (func_id != BPF_FUNC_get_local_storage)
+ goto error;
+ break;
/* devmap returns a pointer to a live net_device ifindex that we cannot
* allow to be modified from bpf side. So do not allow lookup elements
* for now.
if (map->map_type != BPF_MAP_TYPE_SOCKHASH)
goto error;
break;
+ case BPF_FUNC_get_local_storage:
+ if (map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE)
+ goto error;
+ break;
default:
break;
}
}
regs = cur_regs(env);
+
+ /* check that flags argument in get_local_storage(map, flags) is 0,
+ * this is required because get_local_storage() can't return an error.
+ */
+ if (func_id == BPF_FUNC_get_local_storage &&
+ !register_is_null(®s[BPF_REG_2])) {
+ verbose(env, "get_local_storage() doesn't support non-zero flags\n");
+ return -EINVAL;
+ }
+
/* reset caller saved regs */
for (i = 0; i < CALLER_SAVED_REGS; i++) {
mark_reg_not_init(env, regs, caller_saved[i]);
*/
case BPF_FUNC_get_current_uid_gid:
return &bpf_get_current_uid_gid_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_sock_addr_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
}
static const struct bpf_func_proto *
+cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
+ default:
+ return sk_filter_func_proto(func_id, prog);
+ }
+}
+
+static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
switch (func_id) {
return &bpf_sock_hash_update_proto;
case BPF_FUNC_get_socket_cookie:
return &bpf_get_socket_cookie_sock_ops_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
return &bpf_msg_cork_bytes_proto;
case BPF_FUNC_msg_pull_data:
return &bpf_msg_pull_data_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
return &bpf_sk_redirect_map_proto;
case BPF_FUNC_sk_redirect_hash:
return &bpf_sk_redirect_hash_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
default:
return bpf_base_func_proto(func_id);
}
};
const struct bpf_verifier_ops cg_skb_verifier_ops = {
- .get_func_proto = sk_filter_func_proto,
+ .get_func_proto = cg_skb_func_proto,
.is_valid_access = sk_filter_is_valid_access,
.convert_ctx_access = bpf_convert_ctx_access,
};