diff --git a/Tethering/bpf_progs/Android.bp b/Tethering/bpf_progs/Android.bp index 289d75d0b0..5b00dfe786 100644 --- a/Tethering/bpf_progs/Android.bp +++ b/Tethering/bpf_progs/Android.bp @@ -48,10 +48,6 @@ bpf { "-Wall", "-Werror", ], - include_dirs: [ - // TODO: get rid of system/netd. - "system/netd/bpf_progs", // for bpf_net_helpers.h - ], } bpf { @@ -61,8 +57,4 @@ bpf { "-Wall", "-Werror", ], - include_dirs: [ - // TODO: get rid of system/netd. - "system/netd/bpf_progs", // for bpf_net_helpers.h - ], } diff --git a/Tethering/bpf_progs/bpf_net_helpers.h b/Tethering/bpf_progs/bpf_net_helpers.h new file mode 100644 index 0000000000..c7985806fe --- /dev/null +++ b/Tethering/bpf_progs/bpf_net_helpers.h @@ -0,0 +1,72 @@ +/* + * Copyright (C) 2019 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. + */ + +#pragma once + +#include +#include +#include +#include + +// this returns 0 iff skb->sk is NULL +static uint64_t (*bpf_get_socket_cookie)(struct __sk_buff* skb) = (void*)BPF_FUNC_get_socket_cookie; + +static uint32_t (*bpf_get_socket_uid)(struct __sk_buff* skb) = (void*)BPF_FUNC_get_socket_uid; + +static int (*bpf_skb_pull_data)(struct __sk_buff* skb, __u32 len) = (void*)BPF_FUNC_skb_pull_data; + +static int (*bpf_skb_load_bytes)(struct __sk_buff* skb, int off, void* to, + int len) = (void*)BPF_FUNC_skb_load_bytes; + +static int (*bpf_skb_store_bytes)(struct __sk_buff* skb, __u32 offset, const void* from, __u32 len, + __u64 flags) = (void*)BPF_FUNC_skb_store_bytes; + +static int64_t (*bpf_csum_diff)(__be32* from, __u32 from_size, __be32* to, __u32 to_size, + __wsum seed) = (void*)BPF_FUNC_csum_diff; + +static int64_t (*bpf_csum_update)(struct __sk_buff* skb, __wsum csum) = (void*)BPF_FUNC_csum_update; + +static int (*bpf_skb_change_proto)(struct __sk_buff* skb, __be16 proto, + __u64 flags) = (void*)BPF_FUNC_skb_change_proto; +static int (*bpf_l3_csum_replace)(struct __sk_buff* skb, __u32 offset, __u64 from, __u64 to, + __u64 flags) = (void*)BPF_FUNC_l3_csum_replace; +static int (*bpf_l4_csum_replace)(struct __sk_buff* skb, __u32 offset, __u64 from, __u64 to, + __u64 flags) = (void*)BPF_FUNC_l4_csum_replace; +static int (*bpf_redirect)(__u32 ifindex, __u64 flags) = (void*)BPF_FUNC_redirect; +static int (*bpf_redirect_map)(const struct bpf_map_def* map, __u32 key, + __u64 flags) = (void*)BPF_FUNC_redirect_map; + +static int (*bpf_skb_change_head)(struct __sk_buff* skb, __u32 head_room, + __u64 flags) = (void*)BPF_FUNC_skb_change_head; +static int (*bpf_skb_adjust_room)(struct __sk_buff* skb, __s32 len_diff, __u32 mode, + __u64 flags) = (void*)BPF_FUNC_skb_adjust_room; + +// Android only supports little endian architectures +#define htons(x) (__builtin_constant_p(x) ? ___constant_swab16(x) : __builtin_bswap16(x)) +#define htonl(x) (__builtin_constant_p(x) ? ___constant_swab32(x) : __builtin_bswap32(x)) +#define ntohs(x) htons(x) +#define ntohl(x) htonl(x) + +static inline __always_inline __unused bool is_received_skb(struct __sk_buff* skb) { + return skb->pkt_type == PACKET_HOST || skb->pkt_type == PACKET_BROADCAST || + skb->pkt_type == PACKET_MULTICAST; +} + +// try to make the first 'len' header bytes readable via direct packet access +static inline __always_inline void try_make_readable(struct __sk_buff* skb, int len) { + if (len > skb->len) len = skb->len; + if (skb->data_end - skb->data < len) bpf_skb_pull_data(skb, len); +}