1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef NETD_SERVER_TRAFFIC_CONTROLLER_H 18 #define NETD_SERVER_TRAFFIC_CONTROLLER_H 19 20 #include <linux/bpf.h> 21 22 #include <netdutils/StatusOr.h> 23 #include "FirewallController.h" 24 #include "NetlinkListener.h" 25 #include "Network.h" 26 #include "android-base/thread_annotations.h" 27 #include "android-base/unique_fd.h" 28 #include "bpf/BpfMap.h" 29 30 using android::bpf::BpfMap; 31 using android::bpf::IfaceValue; 32 using android::bpf::StatsKey; 33 using android::bpf::StatsValue; 34 using android::bpf::UidTag; 35 36 namespace android { 37 namespace net { 38 39 class DumpWriter; 40 41 class TrafficController { 42 public: 43 TrafficController(); 44 /* 45 * Initialize the whole controller 46 */ 47 netdutils::Status start(); 48 /* 49 * Tag the socket with the specified tag and uid. In the qtaguid module, the 50 * first tag request that grab the spinlock of rb_tree can update the tag 51 * information first and other request need to wait until it finish. All the 52 * tag request will be addressed in the order of they obtaining the spinlock. 53 * In the eBPF implementation, the kernel will try to update the eBPF map 54 * entry with the tag request. And the hashmap update process is protected by 55 * the spinlock initialized with the map. So the behavior of two modules 56 * should be the same. No additional lock needed. 57 */ 58 int tagSocket(int sockFd, uint32_t tag, uid_t uid); 59 60 /* 61 * The untag process is similiar to tag socket and both old qtaguid module and 62 * new eBPF module have spinlock inside the kernel for concurrent update. No 63 * external lock is required. 64 */ 65 int untagSocket(int sockFd); 66 67 /* 68 * Similiar as above, no external lock required. 69 */ 70 int setCounterSet(int counterSetNum, uid_t uid); 71 72 /* 73 * When deleting a tag data, the qtaguid module will grab the spinlock of each 74 * related rb_tree one by one and delete the tag information, counterSet 75 * information, iface stats information and uid stats information one by one. 76 * The new eBPF implementation is done similiarly by removing the entry on 77 * each map one by one. And deleting processes are also protected by the 78 * spinlock of the map. So no additional lock is required. 79 */ 80 int deleteTagData(uint32_t tag, uid_t uid); 81 82 /* 83 * Check if the current device have the bpf traffic stats accounting service 84 * running. 85 */ 86 bool checkBpfStatsEnable(); 87 88 /* 89 * Add the interface name and index pair into the eBPF map. 90 */ 91 int addInterface(const char* name, uint32_t ifaceIndex); 92 93 int changeUidOwnerRule(ChildChain chain, const uid_t uid, FirewallRule rule, FirewallType type); 94 95 int removeUidOwnerRule(const uid_t uid); 96 97 int replaceUidOwnerMap(const std::string& name, bool isWhitelist, 98 const std::vector<int32_t>& uids); 99 100 netdutils::Status updateOwnerMapEntry(BpfMap<uint32_t, uint8_t>& map, uid_t uid, 101 FirewallRule rule, FirewallType type); 102 103 void dump(DumpWriter& dw, bool verbose); 104 105 netdutils::Status replaceUidsInMap(BpfMap<uint32_t, uint8_t>& map, 106 const std::vector<int32_t>& uids, FirewallRule rule, 107 FirewallType type); 108 109 static const String16 DUMP_KEYWORD; 110 111 int toggleUidOwnerMap(ChildChain chain, bool enable); 112 113 private: 114 /* 115 * mCookieTagMap: Store the corresponding tag and uid for a specific socket. 116 * DO NOT hold any locks when modifying this map, otherwise when the untag 117 * operation is waiting for a lock hold by other process and there are more 118 * sockets being closed than can fit in the socket buffer of the netlink socket 119 * that receives them, then the kernel will drop some of these sockets and we 120 * won't delete their tags. 121 * Map Key: uint64_t socket cookie 122 * Map Value: struct UidTag, contains a uint32 uid and a uint32 tag. 123 */ 124 BpfMap<uint64_t, UidTag> mCookieTagMap; 125 126 /* 127 * mUidCounterSetMap: Store the counterSet of a specific uid. 128 * Map Key: uint32 uid. 129 * Map Value: uint32 counterSet specifies if the traffic is a background 130 * or foreground traffic. 131 */ 132 BpfMap<uint32_t, uint8_t> mUidCounterSetMap; 133 134 /* 135 * mAppUidStatsMap: Store the total traffic stats for a uid regardless of 136 * tag, counterSet and iface. The stats is used by TrafficStats.getUidStats 137 * API to return persistent stats for a specific uid since device boot. 138 */ 139 BpfMap<uint32_t, StatsValue> mAppUidStatsMap; 140 141 /* 142 * mUidStatsMap: Store the traffic statistics for a specific combination of 143 * uid, iface and counterSet. We maintain this map in addition to 144 * mTagStatsMap because we want to be able to track per-UID data usage even 145 * if mTagStatsMap is full. 146 * Map Key: Struct StatsKey contains the uid, counterSet and ifaceIndex 147 * information. The Tag in the StatsKey should always be 0. 148 * Map Value: struct Stats, contains packet count and byte count of each 149 * transport protocol on egress and ingress direction. 150 */ 151 BpfMap<StatsKey, StatsValue> mUidStatsMap; 152 153 /* 154 * mTagStatsMap: Store the traffic statistics for a specific combination of 155 * uid, tag, iface and counterSet. Only tagged socket stats should be stored 156 * in this map. 157 * Map Key: Struct StatsKey contains the uid, counterSet and ifaceIndex 158 * information. The tag field should not be 0. 159 * Map Value: struct Stats, contains packet count and byte count of each 160 * transport protocol on egress and ingress direction. 161 */ 162 BpfMap<StatsKey, StatsValue> mTagStatsMap; 163 164 /* 165 * mIfaceIndexNameMap: Store the index name pair of each interface show up 166 * on the device since boot. The interface index is used by the eBPF program 167 * to correctly match the iface name when receiving a packet. 168 */ 169 BpfMap<uint32_t, IfaceValue> mIfaceIndexNameMap; 170 171 /* 172 * mIfaceStataMap: Store per iface traffic stats gathered from xt_bpf 173 * filter. 174 */ 175 BpfMap<uint32_t, StatsValue> mIfaceStatsMap; 176 177 /* 178 * mDozableUidMap: Store uids that have related rules in dozable mode owner match 179 * chain. 180 */ 181 BpfMap<uint32_t, uint8_t> mDozableUidMap GUARDED_BY(mOwnerMatchMutex); 182 183 /* 184 * mStandbyUidMap: Store uids that have related rules in standby mode owner match 185 * chain. 186 */ 187 BpfMap<uint32_t, uint8_t> mStandbyUidMap GUARDED_BY(mOwnerMatchMutex); 188 189 /* 190 * mPowerSaveUidMap: Store uids that have related rules in power save mode owner match 191 * chain. 192 */ 193 BpfMap<uint32_t, uint8_t> mPowerSaveUidMap GUARDED_BY(mOwnerMatchMutex); 194 195 std::unique_ptr<NetlinkListenerInterface> mSkDestroyListener; 196 197 bool ebpfSupported; 198 199 std::mutex mOwnerMatchMutex; 200 201 netdutils::Status loadAndAttachProgram(bpf_attach_type type, const char* path, const char* name, 202 base::unique_fd& cg_fd); 203 204 netdutils::Status initMaps(); 205 // For testing 206 friend class TrafficControllerTest; 207 }; 208 209 } // namespace net 210 } // namespace android 211 212 #endif // NETD_SERVER_TRAFFIC_CONTROLLER_H 213
