Tethering/bpf_progs/bpf_tethering.h - android_packages_modules_Connectivity - Gitiles

 /*
  * 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.
  */

 #pragma once

 #include <linux/if.h>
 #include <linux/if_ether.h>
 #include <linux/in.h>
 #include <linux/in6.h>

 // Common definitions for BPF code in the tethering mainline module.
 // These definitions are available to:
 // - The BPF programs in Tethering/bpf_progs/
 // - JNI code that depends on the bpf_tethering_headers library.

 #define BPF_TETHER_ERRORS    \
     ERR(INVALID_IP_VERSION)  \
     ERR(LOW_TTL)             \
     ERR(INVALID_TCP_HEADER)  \
     ERR(TCP_CONTROL_PACKET)  \
     ERR(NON_GLOBAL_SRC)      \
     ERR(NON_GLOBAL_DST)      \
     ERR(LOCAL_SRC_DST)       \
     ERR(NO_STATS_ENTRY)      \
     ERR(NO_LIMIT_ENTRY)      \
     ERR(BELOW_IPV4_MTU)      \
     ERR(BELOW_IPV6_MTU)      \
     ERR(LIMIT_REACHED)       \
     ERR(CHANGE_HEAD_FAILED)  \
     ERR(TOO_SHORT)           \
     ERR(HAS_IP_OPTIONS)      \
     ERR(IS_IP_FRAG)          \
     ERR(CHECKSUM)            \
     ERR(NON_TCP_UDP)         \
     ERR(NON_TCP)             \
     ERR(SHORT_L4_HEADER)     \
     ERR(SHORT_TCP_HEADER)    \
     ERR(SHORT_UDP_HEADER)    \
     ERR(UDP_CSUM_ZERO)       \
     ERR(TRUNCATED_IPV4)      \
     ERR(_MAX)

 #define ERR(x) BPF_TETHER_ERR_ ##x,
 enum {
     BPF_TETHER_ERRORS
 };
 #undef ERR

 #define ERR(x) #x,
 static const char *bpf_tether_errors[] = {
     BPF_TETHER_ERRORS
 };
 #undef ERR

 // This header file is shared by eBPF kernel programs (C) and netd (C++) and
 // some of the maps are also accessed directly from Java mainline module code.
 //
 // Hence: explicitly pad all relevant structures and assert that their size
 // is the sum of the sizes of their fields.
 #define STRUCT_SIZE(name, size) _Static_assert(sizeof(name) == (size), "Incorrect struct size.")


 #define BPF_PATH_TETHER BPF_PATH "tethering/"

 #define TETHER_STATS_MAP_PATH BPF_PATH_TETHER "map_offload_tether_stats_map"

 typedef uint32_t TetherStatsKey;  // upstream ifindex

 typedef struct {
     uint64_t rxPackets;
     uint64_t rxBytes;
     uint64_t rxErrors;
     uint64_t txPackets;
     uint64_t txBytes;
     uint64_t txErrors;
 } TetherStatsValue;
 STRUCT_SIZE(TetherStatsValue, 6 * 8);  // 48

 #define TETHER_LIMIT_MAP_PATH BPF_PATH_TETHER "map_offload_tether_limit_map"

 typedef uint32_t TetherLimitKey;    // upstream ifindex
 typedef uint64_t TetherLimitValue;  // in bytes

 #define TETHER_DOWNSTREAM6_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_downstream6_rawip"
 #define TETHER_DOWNSTREAM6_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_downstream6_ether"

 #define TETHER_DOWNSTREAM6_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM6_TC_PROG_RAWIP_NAME
 #define TETHER_DOWNSTREAM6_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM6_TC_PROG_ETHER_NAME

 #define TETHER_DOWNSTREAM6_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream6_map"

 // For now tethering offload only needs to support downstreams that use 6-byte MAC addresses,
 // because all downstream types that are currently supported (WiFi, USB, Bluetooth and
 // Ethernet) have 6-byte MAC addresses.

 typedef struct {
     uint32_t iif;              // The input interface index
     uint8_t dstMac[ETH_ALEN];  // destination ethernet mac address (zeroed iff rawip ingress)
     uint8_t zero[2];           // zero pad for 8 byte alignment
     struct in6_addr neigh6;    // The destination IPv6 address
 } TetherDownstream6Key;
 STRUCT_SIZE(TetherDownstream6Key, 4 + 6 + 2 + 16);  // 28

 typedef struct {
     uint32_t oif;             // The output interface to redirect to
     struct ethhdr macHeader;  // includes dst/src mac and ethertype (zeroed iff rawip egress)
     uint16_t pmtu;            // The maximum L3 output path/route mtu
 } Tether6Value;
 STRUCT_SIZE(Tether6Value, 4 + 14 + 2);  // 20

 #define TETHER_DOWNSTREAM64_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream64_map"

 typedef struct {
     uint32_t iif;              // The input interface index
     uint8_t dstMac[ETH_ALEN];  // destination ethernet mac address (zeroed iff rawip ingress)
     uint16_t l4Proto;          // IPPROTO_TCP/UDP/...
     struct in6_addr src6;      // source &
     struct in6_addr dst6;      // destination IPv6 addresses
     __be16 srcPort;            // source &
     __be16 dstPort;            // destination tcp/udp/... ports
 } TetherDownstream64Key;
 STRUCT_SIZE(TetherDownstream64Key, 4 + 6 + 2 + 16 + 16 + 2 + 2);  // 48

 typedef struct {
     uint32_t oif;             // The output interface to redirect to
     struct ethhdr macHeader;  // includes dst/src mac and ethertype (zeroed iff rawip egress)
     uint16_t pmtu;            // The maximum L3 output path/route mtu
     struct in_addr src4;      // source &
     struct in_addr dst4;      // destination IPv4 addresses
     __be16 srcPort;           // source &
     __be16 outPort;           // destination tcp/udp/... ports
     uint64_t lastUsed;        // Kernel updates on each use with bpf_ktime_get_boot_ns()
 } TetherDownstream64Value;
 STRUCT_SIZE(TetherDownstream64Value, 4 + 14 + 2 + 4 + 4 + 2 + 2 + 8);  // 40

 #define TETHER_UPSTREAM6_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_upstream6_rawip"
 #define TETHER_UPSTREAM6_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_upstream6_ether"

 #define TETHER_UPSTREAM6_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM6_TC_PROG_RAWIP_NAME
 #define TETHER_UPSTREAM6_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM6_TC_PROG_ETHER_NAME

 #define TETHER_UPSTREAM6_MAP_PATH BPF_PATH_TETHER "map_offload_tether_upstream6_map"

 typedef struct {
     uint32_t iif;              // The input interface index
     uint8_t dstMac[ETH_ALEN];  // destination ethernet mac address (zeroed iff rawip ingress)
     uint8_t zero[2];           // zero pad for 8 byte alignment
                                // TODO: extend this to include src ip /64 subnet
 } TetherUpstream6Key;
 STRUCT_SIZE(TetherUpstream6Key, 12);

 #define TETHER_DOWNSTREAM4_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_downstream4_rawip"
 #define TETHER_DOWNSTREAM4_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_downstream4_ether"

 #define TETHER_DOWNSTREAM4_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM4_TC_PROG_RAWIP_NAME
 #define TETHER_DOWNSTREAM4_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM4_TC_PROG_ETHER_NAME

 #define TETHER_DOWNSTREAM4_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream4_map"


 #define TETHER_UPSTREAM4_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_upstream4_rawip"
 #define TETHER_UPSTREAM4_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_upstream4_ether"

 #define TETHER_UPSTREAM4_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM4_TC_PROG_RAWIP_NAME
 #define TETHER_UPSTREAM4_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM4_TC_PROG_ETHER_NAME

 #define TETHER_UPSTREAM4_MAP_PATH BPF_PATH_TETHER "map_offload_tether_upstream4_map"

 typedef struct {
     uint32_t iif;              // The input interface index
     uint8_t dstMac[ETH_ALEN];  // destination ethernet mac address (zeroed iff rawip ingress)
     uint16_t l4Proto;          // IPPROTO_TCP/UDP/...
     struct in_addr src4;       // source &
     struct in_addr dst4;       // destination IPv4 addresses
     __be16 srcPort;            // source &
     __be16 dstPort;            // destination TCP/UDP/... ports
 } Tether4Key;
 STRUCT_SIZE(Tether4Key, 4 + 6 + 2 + 4 + 4 + 2 + 2);  // 24

 typedef struct {
     uint32_t oif;             // The output interface to redirect to
     struct ethhdr macHeader;  // includes dst/src mac and ethertype (zeroed iff rawip egress)
     uint16_t pmtu;            // Maximum L3 output path/route mtu
     struct in6_addr src46;    // source &                 (always IPv4 mapped for downstream)
     struct in6_addr dst46;    // destination IP addresses (may be IPv4 mapped or IPv6 for upstream)
     __be16 srcPort;           // source &
     __be16 dstPort;           // destination tcp/udp/... ports
     uint64_t last_used;       // Kernel updates on each use with bpf_ktime_get_boot_ns()
 } Tether4Value;
 STRUCT_SIZE(Tether4Value, 4 + 14 + 2 + 16 + 16 + 2 + 2 + 8);  // 64

 #define TETHER_DOWNSTREAM_XDP_PROG_RAWIP_NAME "prog_offload_xdp_tether_downstream_rawip"
 #define TETHER_DOWNSTREAM_XDP_PROG_ETHER_NAME "prog_offload_xdp_tether_downstream_ether"

 #define TETHER_DOWNSTREAM_XDP_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM_XDP_PROG_RAWIP_NAME
 #define TETHER_DOWNSTREAM_XDP_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM_XDP_PROG_ETHER_NAME

 #define TETHER_UPSTREAM_XDP_PROG_RAWIP_NAME "prog_offload_xdp_tether_upstream_rawip"
 #define TETHER_UPSTREAM_XDP_PROG_ETHER_NAME "prog_offload_xdp_tether_upstream_ether"

 #define TETHER_UPSTREAM_XDP_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM_XDP_PROG_RAWIP_NAME
 #define TETHER_UPSTREAM_XDP_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM_XDP_PROG_ETHER_NAME

 #undef STRUCT_SIZE
	/*
	* 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.
	*/

	#pragma once

	#include <linux/if.h>
	#include <linux/if_ether.h>
	#include <linux/in.h>
	#include <linux/in6.h>

	// Common definitions for BPF code in the tethering mainline module.
	// These definitions are available to:
	// - The BPF programs in Tethering/bpf_progs/
	// - JNI code that depends on the bpf_tethering_headers library.

	#define BPF_TETHER_ERRORS \
	ERR(INVALID_IP_VERSION) \
	ERR(LOW_TTL) \
	ERR(INVALID_TCP_HEADER) \
	ERR(TCP_CONTROL_PACKET) \
	ERR(NON_GLOBAL_SRC) \
	ERR(NON_GLOBAL_DST) \
	ERR(LOCAL_SRC_DST) \
	ERR(NO_STATS_ENTRY) \
	ERR(NO_LIMIT_ENTRY) \
	ERR(BELOW_IPV4_MTU) \
	ERR(BELOW_IPV6_MTU) \
	ERR(LIMIT_REACHED) \
	ERR(CHANGE_HEAD_FAILED) \
	ERR(TOO_SHORT) \
	ERR(HAS_IP_OPTIONS) \
	ERR(IS_IP_FRAG) \
	ERR(CHECKSUM) \
	ERR(NON_TCP_UDP) \
	ERR(NON_TCP) \
	ERR(SHORT_L4_HEADER) \
	ERR(SHORT_TCP_HEADER) \
	ERR(SHORT_UDP_HEADER) \
	ERR(UDP_CSUM_ZERO) \
	ERR(TRUNCATED_IPV4) \
	ERR(_MAX)

	#define ERR(x) BPF_TETHER_ERR_ ##x,
	enum {
	BPF_TETHER_ERRORS
	};
	#undef ERR

	#define ERR(x) #x,
	static const char *bpf_tether_errors[] = {
	BPF_TETHER_ERRORS
	};
	#undef ERR

	// This header file is shared by eBPF kernel programs (C) and netd (C++) and
	// some of the maps are also accessed directly from Java mainline module code.
	//
	// Hence: explicitly pad all relevant structures and assert that their size
	// is the sum of the sizes of their fields.
	#define STRUCT_SIZE(name, size) _Static_assert(sizeof(name) == (size), "Incorrect struct size.")


	#define BPF_PATH_TETHER BPF_PATH "tethering/"

	#define TETHER_STATS_MAP_PATH BPF_PATH_TETHER "map_offload_tether_stats_map"

	typedef uint32_t TetherStatsKey; // upstream ifindex

	typedef struct {
	uint64_t rxPackets;
	uint64_t rxBytes;
	uint64_t rxErrors;
	uint64_t txPackets;
	uint64_t txBytes;
	uint64_t txErrors;
	} TetherStatsValue;
	STRUCT_SIZE(TetherStatsValue, 6 * 8); // 48

	#define TETHER_LIMIT_MAP_PATH BPF_PATH_TETHER "map_offload_tether_limit_map"

	typedef uint32_t TetherLimitKey; // upstream ifindex
	typedef uint64_t TetherLimitValue; // in bytes

	#define TETHER_DOWNSTREAM6_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_downstream6_rawip"
	#define TETHER_DOWNSTREAM6_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_downstream6_ether"

	#define TETHER_DOWNSTREAM6_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM6_TC_PROG_RAWIP_NAME
	#define TETHER_DOWNSTREAM6_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM6_TC_PROG_ETHER_NAME

	#define TETHER_DOWNSTREAM6_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream6_map"

	// For now tethering offload only needs to support downstreams that use 6-byte MAC addresses,
	// because all downstream types that are currently supported (WiFi, USB, Bluetooth and
	// Ethernet) have 6-byte MAC addresses.

	typedef struct {
	uint32_t iif; // The input interface index
	uint8_t dstMac[ETH_ALEN]; // destination ethernet mac address (zeroed iff rawip ingress)
	uint8_t zero[2]; // zero pad for 8 byte alignment
	struct in6_addr neigh6; // The destination IPv6 address
	} TetherDownstream6Key;
	STRUCT_SIZE(TetherDownstream6Key, 4 + 6 + 2 + 16); // 28

	typedef struct {
	uint32_t oif; // The output interface to redirect to
	struct ethhdr macHeader; // includes dst/src mac and ethertype (zeroed iff rawip egress)
	uint16_t pmtu; // The maximum L3 output path/route mtu
	} Tether6Value;
	STRUCT_SIZE(Tether6Value, 4 + 14 + 2); // 20

	#define TETHER_DOWNSTREAM64_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream64_map"

	typedef struct {
	uint32_t iif; // The input interface index
	uint8_t dstMac[ETH_ALEN]; // destination ethernet mac address (zeroed iff rawip ingress)
	uint16_t l4Proto; // IPPROTO_TCP/UDP/...
	struct in6_addr src6; // source &
	struct in6_addr dst6; // destination IPv6 addresses
	__be16 srcPort; // source &
	__be16 dstPort; // destination tcp/udp/... ports
	} TetherDownstream64Key;
	STRUCT_SIZE(TetherDownstream64Key, 4 + 6 + 2 + 16 + 16 + 2 + 2); // 48

	typedef struct {
	uint32_t oif; // The output interface to redirect to
	struct ethhdr macHeader; // includes dst/src mac and ethertype (zeroed iff rawip egress)
	uint16_t pmtu; // The maximum L3 output path/route mtu
	struct in_addr src4; // source &
	struct in_addr dst4; // destination IPv4 addresses
	__be16 srcPort; // source &
	__be16 outPort; // destination tcp/udp/... ports
	uint64_t lastUsed; // Kernel updates on each use with bpf_ktime_get_boot_ns()
	} TetherDownstream64Value;
	STRUCT_SIZE(TetherDownstream64Value, 4 + 14 + 2 + 4 + 4 + 2 + 2 + 8); // 40

	#define TETHER_UPSTREAM6_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_upstream6_rawip"
	#define TETHER_UPSTREAM6_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_upstream6_ether"

	#define TETHER_UPSTREAM6_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM6_TC_PROG_RAWIP_NAME
	#define TETHER_UPSTREAM6_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM6_TC_PROG_ETHER_NAME

	#define TETHER_UPSTREAM6_MAP_PATH BPF_PATH_TETHER "map_offload_tether_upstream6_map"

	typedef struct {
	uint32_t iif; // The input interface index
	uint8_t dstMac[ETH_ALEN]; // destination ethernet mac address (zeroed iff rawip ingress)
	uint8_t zero[2]; // zero pad for 8 byte alignment
	// TODO: extend this to include src ip /64 subnet
	} TetherUpstream6Key;
	STRUCT_SIZE(TetherUpstream6Key, 12);

	#define TETHER_DOWNSTREAM4_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_downstream4_rawip"
	#define TETHER_DOWNSTREAM4_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_downstream4_ether"

	#define TETHER_DOWNSTREAM4_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM4_TC_PROG_RAWIP_NAME
	#define TETHER_DOWNSTREAM4_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM4_TC_PROG_ETHER_NAME

	#define TETHER_DOWNSTREAM4_MAP_PATH BPF_PATH_TETHER "map_offload_tether_downstream4_map"


	#define TETHER_UPSTREAM4_TC_PROG_RAWIP_NAME "prog_offload_schedcls_tether_upstream4_rawip"
	#define TETHER_UPSTREAM4_TC_PROG_ETHER_NAME "prog_offload_schedcls_tether_upstream4_ether"

	#define TETHER_UPSTREAM4_TC_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM4_TC_PROG_RAWIP_NAME
	#define TETHER_UPSTREAM4_TC_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM4_TC_PROG_ETHER_NAME

	#define TETHER_UPSTREAM4_MAP_PATH BPF_PATH_TETHER "map_offload_tether_upstream4_map"

	typedef struct {
	uint32_t iif; // The input interface index
	uint8_t dstMac[ETH_ALEN]; // destination ethernet mac address (zeroed iff rawip ingress)
	uint16_t l4Proto; // IPPROTO_TCP/UDP/...
	struct in_addr src4; // source &
	struct in_addr dst4; // destination IPv4 addresses
	__be16 srcPort; // source &
	__be16 dstPort; // destination TCP/UDP/... ports
	} Tether4Key;
	STRUCT_SIZE(Tether4Key, 4 + 6 + 2 + 4 + 4 + 2 + 2); // 24

	typedef struct {
	uint32_t oif; // The output interface to redirect to
	struct ethhdr macHeader; // includes dst/src mac and ethertype (zeroed iff rawip egress)
	uint16_t pmtu; // Maximum L3 output path/route mtu
	struct in6_addr src46; // source & (always IPv4 mapped for downstream)
	struct in6_addr dst46; // destination IP addresses (may be IPv4 mapped or IPv6 for upstream)
	__be16 srcPort; // source &
	__be16 dstPort; // destination tcp/udp/... ports
	uint64_t last_used; // Kernel updates on each use with bpf_ktime_get_boot_ns()
	} Tether4Value;
	STRUCT_SIZE(Tether4Value, 4 + 14 + 2 + 16 + 16 + 2 + 2 + 8); // 64

	#define TETHER_DOWNSTREAM_XDP_PROG_RAWIP_NAME "prog_offload_xdp_tether_downstream_rawip"
	#define TETHER_DOWNSTREAM_XDP_PROG_ETHER_NAME "prog_offload_xdp_tether_downstream_ether"

	#define TETHER_DOWNSTREAM_XDP_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM_XDP_PROG_RAWIP_NAME
	#define TETHER_DOWNSTREAM_XDP_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_DOWNSTREAM_XDP_PROG_ETHER_NAME

	#define TETHER_UPSTREAM_XDP_PROG_RAWIP_NAME "prog_offload_xdp_tether_upstream_rawip"
	#define TETHER_UPSTREAM_XDP_PROG_ETHER_NAME "prog_offload_xdp_tether_upstream_ether"

	#define TETHER_UPSTREAM_XDP_PROG_RAWIP_PATH BPF_PATH_TETHER TETHER_UPSTREAM_XDP_PROG_RAWIP_NAME
	#define TETHER_UPSTREAM_XDP_PROG_ETHER_PATH BPF_PATH_TETHER TETHER_UPSTREAM_XDP_PROG_ETHER_NAME

	#undef STRUCT_SIZE