server/OffloadUtils.h - platform/system/netd - Git at Google

 /*
  * 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 <android-base/result.h>
 #include <errno.h>
 #include <linux/if_ether.h>
 #include <linux/rtnetlink.h>

 #include <string>

 #include "bpf/BpfUtils.h"
 #include "netdbpf/bpf_shared.h"

 namespace android {
 namespace net {

 // For better code clarity - do not change values - used for booleans like
 // with_ethernet_header or isEthernet.
 constexpr bool RAWIP = false;
 constexpr bool ETHER = true;

 // For better code clarity when used for 'bool ingress' parameter.
 constexpr bool EGRESS = false;
 constexpr bool INGRESS = true;

 // For better code clarify when used for 'bool downstream' parameter.
 //
 // This is talking about the direction of travel of the offloaded packets.
 //
 // Upstream means packets heading towards the internet/uplink (upload),
 // thus for tethering this is attached to ingress on the downstream interface,
 // while for clat this is attached to egress on the v4-* clat interface.
 //
 // Downstream means packets coming from the internet/uplink (download), thus
 // for both clat and tethering this is attached to ingress on the upstream interface.
 constexpr bool UPSTREAM = false;
 constexpr bool DOWNSTREAM = true;

 // The priority of clat/tether hooks - smaller is higher priority.
 // TC tether is higher priority then TC clat to match XDP winning over TC.
 constexpr uint16_t PRIO_TETHER6 = 1;
 constexpr uint16_t PRIO_TETHER4 = 2;
 constexpr uint16_t PRIO_CLAT = 3;

 // this returns an ARPHRD_* constant or a -errno
 int hardwareAddressType(const std::string& interface);

 base::Result<bool> isEthernet(const std::string& interface);

 inline int getClatEgress4MapFd(void) {
     const int fd = bpf::mapRetrieveRW(CLAT_EGRESS4_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getClatEgress4ProgFd(bool with_ethernet_header) {
     const int fd = bpf::retrieveProgram(with_ethernet_header ? CLAT_EGRESS4_PROG_ETHER_PATH
                                                              : CLAT_EGRESS4_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getClatIngress6MapFd(void) {
     const int fd = bpf::mapRetrieveRW(CLAT_INGRESS6_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getClatIngress6ProgFd(bool with_ethernet_header) {
     const int fd = bpf::retrieveProgram(with_ethernet_header ? CLAT_INGRESS6_PROG_ETHER_PATH
                                                              : CLAT_INGRESS6_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstream6MapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM6_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstream64MapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM64_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstream4MapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM4_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstream6TcProgFd(bool with_ethernet_header) {
     const int fd =
             bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM6_TC_PROG_ETHER_PATH
                                                       : TETHER_DOWNSTREAM6_TC_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstream4TcProgFd(bool with_ethernet_header) {
     const int fd =
             bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM4_TC_PROG_ETHER_PATH
                                                       : TETHER_DOWNSTREAM4_TC_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherUpstream6MapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_UPSTREAM6_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherUpstream4MapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_UPSTREAM4_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherUpstream6TcProgFd(bool with_ethernet_header) {
     const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM6_TC_PROG_ETHER_PATH
                                                              : TETHER_UPSTREAM6_TC_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherUpstream4TcProgFd(bool with_ethernet_header) {
     const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM4_TC_PROG_ETHER_PATH
                                                              : TETHER_UPSTREAM4_TC_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTether6TcProgFd(bool with_ethernet_header, bool downstream) {
     return downstream ? getTetherDownstream6TcProgFd(with_ethernet_header)
                       : getTetherUpstream6TcProgFd(with_ethernet_header);
 }

 inline int getTether4TcProgFd(bool with_ethernet_header, bool downstream) {
     return downstream ? getTetherDownstream4TcProgFd(with_ethernet_header)
                       : getTetherUpstream4TcProgFd(with_ethernet_header);
 }

 inline int getTetherStatsMapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_STATS_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherLimitMapFd(void) {
     const int fd = bpf::mapRetrieveRW(TETHER_LIMIT_MAP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherDownstreamXdpProgFd(bool with_ethernet_header) {
     const int fd =
             bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM_XDP_PROG_ETHER_PATH
                                                       : TETHER_DOWNSTREAM_XDP_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherUpstreamXdpProgFd(bool with_ethernet_header) {
     const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM_XDP_PROG_ETHER_PATH
                                                              : TETHER_UPSTREAM_XDP_PROG_RAWIP_PATH);
     return (fd == -1) ? -errno : fd;
 }

 inline int getTetherXdpProgFd(bool with_ethernet_header, bool downstream) {
     return downstream ? getTetherDownstreamXdpProgFd(with_ethernet_header)
                       : getTetherUpstreamXdpProgFd(with_ethernet_header);
 }

 int doTcQdiscClsact(int ifIndex, uint16_t nlMsgType, uint16_t nlMsgFlags);

 inline int tcQdiscAddDevClsact(int ifIndex) {
     return doTcQdiscClsact(ifIndex, RTM_NEWQDISC, NLM_F_EXCL | NLM_F_CREATE);
 }

 inline int tcQdiscReplaceDevClsact(int ifIndex) {
     return doTcQdiscClsact(ifIndex, RTM_NEWQDISC, NLM_F_CREATE | NLM_F_REPLACE);
 }

 inline int tcQdiscDelDevClsact(int ifIndex) {
     return doTcQdiscClsact(ifIndex, RTM_DELQDISC, 0);
 }

 // tc filter add dev .. in/egress prio ? protocol ipv6/ip bpf object-pinned /sys/fs/bpf/...
 // direct-action
 int tcFilterAddDevBpf(int ifIndex, bool ingress, uint16_t prio, uint16_t proto, int bpfFd,
                       bool ethernet, bool downstream);

 // tc filter add dev .. ingress prio 3 protocol ipv6 bpf object-pinned /sys/fs/bpf/... direct-action
 inline int tcFilterAddDevIngressClatIpv6(int ifIndex, int bpfFd, bool ethernet) {
     return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_CLAT, ETH_P_IPV6, bpfFd, ethernet, DOWNSTREAM);
 }

 // tc filter add dev .. egress prio 3 protocol ip bpf object-pinned /sys/fs/bpf/... direct-action
 inline int tcFilterAddDevEgressClatIpv4(int ifIndex, int bpfFd, bool ethernet) {
     return tcFilterAddDevBpf(ifIndex, EGRESS, PRIO_CLAT, ETH_P_IP, bpfFd, ethernet, UPSTREAM);
 }

 // tc filter add dev .. ingress prio 1 protocol ipv6 bpf object-pinned /sys/fs/bpf/... direct-action
 inline int tcFilterAddDevIngress6Tether(int ifIndex, int bpfFd, bool ethernet, bool downstream) {
     return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_TETHER6, ETH_P_IPV6, bpfFd, ethernet,
                              downstream);
 }

 // tc filter add dev .. ingress prio 2 protocol ip bpf object-pinned /sys/fs/bpf/... direct-action
 inline int tcFilterAddDevIngress4Tether(int ifIndex, int bpfFd, bool ethernet, bool downstream) {
     return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_TETHER4, ETH_P_IP, bpfFd, ethernet, downstream);
 }

 // tc filter del dev .. in/egress prio .. protocol ..
 int tcFilterDelDev(int ifIndex, bool ingress, uint16_t prio, uint16_t proto);

 // tc filter del dev .. ingress prio 3 protocol ipv6
 inline int tcFilterDelDevIngressClatIpv6(int ifIndex) {
     return tcFilterDelDev(ifIndex, INGRESS, PRIO_CLAT, ETH_P_IPV6);
 }

 // tc filter del dev .. egress prio 3 protocol ip
 inline int tcFilterDelDevEgressClatIpv4(int ifIndex) {
     return tcFilterDelDev(ifIndex, EGRESS, PRIO_CLAT, ETH_P_IP);
 }

 // tc filter del dev .. ingress prio 1 protocol ipv6
 inline int tcFilterDelDevIngress6Tether(int ifIndex) {
     return tcFilterDelDev(ifIndex, INGRESS, PRIO_TETHER6, ETH_P_IPV6);
 }

 // tc filter del dev .. ingress prio 2 protocol ip
 inline int tcFilterDelDevIngress4Tether(int ifIndex) {
     return tcFilterDelDev(ifIndex, INGRESS, PRIO_TETHER4, ETH_P_IP);
 }

 }  // namespace net
 }  // namespace android
	/*
	* 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 <android-base/result.h>
	#include <errno.h>
	#include <linux/if_ether.h>
	#include <linux/rtnetlink.h>

	#include <string>

	#include "bpf/BpfUtils.h"
	#include "netdbpf/bpf_shared.h"

	namespace android {
	namespace net {

	// For better code clarity - do not change values - used for booleans like
	// with_ethernet_header or isEthernet.
	constexpr bool RAWIP = false;
	constexpr bool ETHER = true;

	// For better code clarity when used for 'bool ingress' parameter.
	constexpr bool EGRESS = false;
	constexpr bool INGRESS = true;

	// For better code clarify when used for 'bool downstream' parameter.
	//
	// This is talking about the direction of travel of the offloaded packets.
	//
	// Upstream means packets heading towards the internet/uplink (upload),
	// thus for tethering this is attached to ingress on the downstream interface,
	// while for clat this is attached to egress on the v4-* clat interface.
	//
	// Downstream means packets coming from the internet/uplink (download), thus
	// for both clat and tethering this is attached to ingress on the upstream interface.
	constexpr bool UPSTREAM = false;
	constexpr bool DOWNSTREAM = true;

	// The priority of clat/tether hooks - smaller is higher priority.
	// TC tether is higher priority then TC clat to match XDP winning over TC.
	constexpr uint16_t PRIO_TETHER6 = 1;
	constexpr uint16_t PRIO_TETHER4 = 2;
	constexpr uint16_t PRIO_CLAT = 3;

	// this returns an ARPHRD_* constant or a -errno
	int hardwareAddressType(const std::string& interface);

	base::Result<bool> isEthernet(const std::string& interface);

	inline int getClatEgress4MapFd(void) {
	const int fd = bpf::mapRetrieveRW(CLAT_EGRESS4_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getClatEgress4ProgFd(bool with_ethernet_header) {
	const int fd = bpf::retrieveProgram(with_ethernet_header ? CLAT_EGRESS4_PROG_ETHER_PATH
	: CLAT_EGRESS4_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getClatIngress6MapFd(void) {
	const int fd = bpf::mapRetrieveRW(CLAT_INGRESS6_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getClatIngress6ProgFd(bool with_ethernet_header) {
	const int fd = bpf::retrieveProgram(with_ethernet_header ? CLAT_INGRESS6_PROG_ETHER_PATH
	: CLAT_INGRESS6_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstream6MapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM6_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstream64MapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM64_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstream4MapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_DOWNSTREAM4_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstream6TcProgFd(bool with_ethernet_header) {
	const int fd =
	bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM6_TC_PROG_ETHER_PATH
	: TETHER_DOWNSTREAM6_TC_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstream4TcProgFd(bool with_ethernet_header) {
	const int fd =
	bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM4_TC_PROG_ETHER_PATH
	: TETHER_DOWNSTREAM4_TC_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherUpstream6MapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_UPSTREAM6_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherUpstream4MapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_UPSTREAM4_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherUpstream6TcProgFd(bool with_ethernet_header) {
	const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM6_TC_PROG_ETHER_PATH
	: TETHER_UPSTREAM6_TC_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherUpstream4TcProgFd(bool with_ethernet_header) {
	const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM4_TC_PROG_ETHER_PATH
	: TETHER_UPSTREAM4_TC_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTether6TcProgFd(bool with_ethernet_header, bool downstream) {
	return downstream ? getTetherDownstream6TcProgFd(with_ethernet_header)
	: getTetherUpstream6TcProgFd(with_ethernet_header);
	}

	inline int getTether4TcProgFd(bool with_ethernet_header, bool downstream) {
	return downstream ? getTetherDownstream4TcProgFd(with_ethernet_header)
	: getTetherUpstream4TcProgFd(with_ethernet_header);
	}

	inline int getTetherStatsMapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_STATS_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherLimitMapFd(void) {
	const int fd = bpf::mapRetrieveRW(TETHER_LIMIT_MAP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherDownstreamXdpProgFd(bool with_ethernet_header) {
	const int fd =
	bpf::retrieveProgram(with_ethernet_header ? TETHER_DOWNSTREAM_XDP_PROG_ETHER_PATH
	: TETHER_DOWNSTREAM_XDP_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherUpstreamXdpProgFd(bool with_ethernet_header) {
	const int fd = bpf::retrieveProgram(with_ethernet_header ? TETHER_UPSTREAM_XDP_PROG_ETHER_PATH
	: TETHER_UPSTREAM_XDP_PROG_RAWIP_PATH);
	return (fd == -1) ? -errno : fd;
	}

	inline int getTetherXdpProgFd(bool with_ethernet_header, bool downstream) {
	return downstream ? getTetherDownstreamXdpProgFd(with_ethernet_header)
	: getTetherUpstreamXdpProgFd(with_ethernet_header);
	}

	int doTcQdiscClsact(int ifIndex, uint16_t nlMsgType, uint16_t nlMsgFlags);

	inline int tcQdiscAddDevClsact(int ifIndex) {
	return doTcQdiscClsact(ifIndex, RTM_NEWQDISC, NLM_F_EXCL \| NLM_F_CREATE);
	}

	inline int tcQdiscReplaceDevClsact(int ifIndex) {
	return doTcQdiscClsact(ifIndex, RTM_NEWQDISC, NLM_F_CREATE \| NLM_F_REPLACE);
	}

	inline int tcQdiscDelDevClsact(int ifIndex) {
	return doTcQdiscClsact(ifIndex, RTM_DELQDISC, 0);
	}

	// tc filter add dev .. in/egress prio ? protocol ipv6/ip bpf object-pinned /sys/fs/bpf/...
	// direct-action
	int tcFilterAddDevBpf(int ifIndex, bool ingress, uint16_t prio, uint16_t proto, int bpfFd,
	bool ethernet, bool downstream);

	// tc filter add dev .. ingress prio 3 protocol ipv6 bpf object-pinned /sys/fs/bpf/... direct-action
	inline int tcFilterAddDevIngressClatIpv6(int ifIndex, int bpfFd, bool ethernet) {
	return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_CLAT, ETH_P_IPV6, bpfFd, ethernet, DOWNSTREAM);
	}

	// tc filter add dev .. egress prio 3 protocol ip bpf object-pinned /sys/fs/bpf/... direct-action
	inline int tcFilterAddDevEgressClatIpv4(int ifIndex, int bpfFd, bool ethernet) {
	return tcFilterAddDevBpf(ifIndex, EGRESS, PRIO_CLAT, ETH_P_IP, bpfFd, ethernet, UPSTREAM);
	}

	// tc filter add dev .. ingress prio 1 protocol ipv6 bpf object-pinned /sys/fs/bpf/... direct-action
	inline int tcFilterAddDevIngress6Tether(int ifIndex, int bpfFd, bool ethernet, bool downstream) {
	return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_TETHER6, ETH_P_IPV6, bpfFd, ethernet,
	downstream);
	}

	// tc filter add dev .. ingress prio 2 protocol ip bpf object-pinned /sys/fs/bpf/... direct-action
	inline int tcFilterAddDevIngress4Tether(int ifIndex, int bpfFd, bool ethernet, bool downstream) {
	return tcFilterAddDevBpf(ifIndex, INGRESS, PRIO_TETHER4, ETH_P_IP, bpfFd, ethernet, downstream);
	}

	// tc filter del dev .. in/egress prio .. protocol ..
	int tcFilterDelDev(int ifIndex, bool ingress, uint16_t prio, uint16_t proto);

	// tc filter del dev .. ingress prio 3 protocol ipv6
	inline int tcFilterDelDevIngressClatIpv6(int ifIndex) {
	return tcFilterDelDev(ifIndex, INGRESS, PRIO_CLAT, ETH_P_IPV6);
	}

	// tc filter del dev .. egress prio 3 protocol ip
	inline int tcFilterDelDevEgressClatIpv4(int ifIndex) {
	return tcFilterDelDev(ifIndex, EGRESS, PRIO_CLAT, ETH_P_IP);
	}

	// tc filter del dev .. ingress prio 1 protocol ipv6
	inline int tcFilterDelDevIngress6Tether(int ifIndex) {
	return tcFilterDelDev(ifIndex, INGRESS, PRIO_TETHER6, ETH_P_IPV6);
	}

	// tc filter del dev .. ingress prio 2 protocol ip
	inline int tcFilterDelDevIngress4Tether(int ifIndex) {
	return tcFilterDelDev(ifIndex, INGRESS, PRIO_TETHER4, ETH_P_IP);
	}

	} // namespace net
	} // namespace android