54 lines
1.8 KiB
C
54 lines
1.8 KiB
C
/*
|
|
* Copyright (C) 2021 The Android Open Source Project
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include <linux/if_ether.h>
|
|
#include <linux/in.h>
|
|
#include <linux/ip.h>
|
|
|
|
// The resulting .o needs to load on the Android S bpfloader
|
|
#define BPFLOADER_MIN_VER BPFLOADER_S_VERSION
|
|
|
|
#include "bpf_helpers.h"
|
|
#include "bpf_net_helpers.h"
|
|
#include "bpf_tethering.h"
|
|
|
|
// Used only by TetheringPrivilegedTests, not by production code.
|
|
DEFINE_BPF_MAP_GRW(tether_downstream6_map, HASH, TetherDownstream6Key, Tether6Value, 16,
|
|
AID_NETWORK_STACK)
|
|
// Used only by BpfBitmapTest, not by production code.
|
|
DEFINE_BPF_MAP_GRW(bitmap, ARRAY, int, uint64_t, 2,
|
|
AID_NETWORK_STACK)
|
|
|
|
DEFINE_BPF_PROG_KVER("xdp/drop_ipv4_udp_ether", AID_ROOT, AID_NETWORK_STACK,
|
|
xdp_test, KVER(5, 9, 0))
|
|
(struct xdp_md *ctx) {
|
|
void *data = (void *)(long)ctx->data;
|
|
void *data_end = (void *)(long)ctx->data_end;
|
|
|
|
struct ethhdr *eth = data;
|
|
int hsize = sizeof(*eth);
|
|
|
|
struct iphdr *ip = data + hsize;
|
|
hsize += sizeof(struct iphdr);
|
|
|
|
if (data + hsize > data_end) return XDP_PASS;
|
|
if (eth->h_proto != htons(ETH_P_IP)) return XDP_PASS;
|
|
if (ip->protocol == IPPROTO_UDP) return XDP_DROP;
|
|
return XDP_PASS;
|
|
}
|
|
|
|
LICENSE("Apache 2.0");
|