1 /*
2  * Copyright (C) 2018 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 _BPF_NETWORKSTATS_H
18 #define _BPF_NETWORKSTATS_H
19 
20 #include <bpf/BpfMap.h>
21 #include "bpf_shared.h"
22 
23 namespace android {
24 namespace bpf {
25 
26 // TODO: set this to a proper value based on the map size;
27 constexpr int TAG_STATS_MAP_SOFT_LIMIT = 3;
28 constexpr int UID_ALL = -1;
29 constexpr int TAG_ALL = -1;
30 constexpr int TAG_NONE = 0;
31 constexpr int SET_ALL = -1;
32 constexpr int SET_DEFAULT = 0;
33 constexpr int SET_FOREGROUND = 1;
34 
35 // The limit for stats received by a unknown interface;
36 constexpr const int64_t MAX_UNKNOWN_IFACE_BYTES = 100 * 1000;
37 
38 // This is used by
39 // frameworks/base/core/jni/com_android_internal_net_NetworkStatsFactory.cpp
40 // make sure it is consistent with the JNI code before changing this.
41 struct stats_line {
42     char iface[32];
43     uint32_t uid;
44     uint32_t set;
45     uint32_t tag;
46     int64_t rxBytes;
47     int64_t rxPackets;
48     int64_t txBytes;
49     int64_t txPackets;
50 
51     stats_line& operator=(const stats_line& rhs);
52     stats_line& operator+=(const stats_line& rhs);
53 };
54 
55 bool operator==(const stats_line& lhs, const stats_line& rhs);
56 bool operator<(const stats_line& lhs, const stats_line& rhs);
57 
58 // For test only
59 int bpfGetUidStatsInternal(uid_t uid, Stats* stats,
60                            const BpfMap<uint32_t, StatsValue>& appUidStatsMap);
61 // For test only
62 int bpfGetIfaceStatsInternal(const char* iface, Stats* stats,
63                              const BpfMap<uint32_t, StatsValue>& ifaceStatsMap,
64                              const BpfMap<uint32_t, IfaceValue>& ifaceNameMap);
65 // For test only
66 int parseBpfNetworkStatsDetailInternal(std::vector<stats_line>* lines,
67                                        const std::vector<std::string>& limitIfaces, int limitTag,
68                                        int limitUid, const BpfMap<StatsKey, StatsValue>& statsMap,
69                                        const BpfMap<uint32_t, IfaceValue>& ifaceMap);
70 // For test only
71 int cleanStatsMapInternal(const base::unique_fd& cookieTagMap, const base::unique_fd& tagStatsMap);
72 // For test only
73 template <class Key>
getIfaceNameFromMap(const BpfMap<uint32_t,IfaceValue> & ifaceMap,const BpfMap<Key,StatsValue> & statsMap,uint32_t ifaceIndex,char * ifname,const Key & curKey,int64_t * unknownIfaceBytesTotal)74 int getIfaceNameFromMap(const BpfMap<uint32_t, IfaceValue>& ifaceMap,
75                         const BpfMap<Key, StatsValue>& statsMap, uint32_t ifaceIndex, char* ifname,
76                         const Key& curKey, int64_t* unknownIfaceBytesTotal) {
77     auto iface = ifaceMap.readValue(ifaceIndex);
78     if (!iface.ok()) {
79         maybeLogUnknownIface(ifaceIndex, statsMap, curKey, unknownIfaceBytesTotal);
80         return -ENODEV;
81     }
82     strlcpy(ifname, iface.value().name, sizeof(IfaceValue));
83     return 0;
84 }
85 
86 template <class Key>
maybeLogUnknownIface(int ifaceIndex,const BpfMap<Key,StatsValue> & statsMap,const Key & curKey,int64_t * unknownIfaceBytesTotal)87 void maybeLogUnknownIface(int ifaceIndex, const BpfMap<Key, StatsValue>& statsMap,
88                           const Key& curKey, int64_t* unknownIfaceBytesTotal) {
89     // Have we already logged an error?
90     if (*unknownIfaceBytesTotal == -1) {
91         return;
92     }
93 
94     // Are we undercounting enough data to be worth logging?
95     auto statsEntry = statsMap.readValue(curKey);
96     if (!statsEntry.ok()) {
97         // No data is being undercounted.
98         return;
99     }
100 
101     *unknownIfaceBytesTotal += (statsEntry.value().rxBytes + statsEntry.value().txBytes);
102     if (*unknownIfaceBytesTotal >= MAX_UNKNOWN_IFACE_BYTES) {
103         ALOGE("Unknown name for ifindex %d with more than %" PRId64 " bytes of traffic", ifaceIndex,
104               *unknownIfaceBytesTotal);
105         *unknownIfaceBytesTotal = -1;
106     }
107 }
108 
109 // For test only
110 int parseBpfNetworkStatsDevInternal(std::vector<stats_line>* lines,
111                                     const BpfMap<uint32_t, StatsValue>& statsMap,
112                                     const BpfMap<uint32_t, IfaceValue>& ifaceMap);
113 
114 int bpfGetUidStats(uid_t uid, Stats* stats);
115 int bpfGetIfaceStats(const char* iface, Stats* stats);
116 int parseBpfNetworkStatsDetail(std::vector<stats_line>* lines,
117                                const std::vector<std::string>& limitIfaces, int limitTag,
118                                int limitUid);
119 
120 int parseBpfNetworkStatsDev(std::vector<stats_line>* lines);
121 void groupNetworkStats(std::vector<stats_line>* lines);
122 int cleanStatsMap();
123 }  // namespace bpf
124 }  // namespace android
125 
126 #endif  // _BPF_NETWORKSTATS_H
127