1 /*
2  * Copyright (C) 2011 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 #ifndef _BANDWIDTH_CONTROLLER_H
17 #define _BANDWIDTH_CONTROLLER_H
18 
19 #include <list>
20 #include <string>
21 #include <utility>  // for pair
22 
23 #include <sysutils/SocketClient.h>
24 #include <utils/RWLock.h>
25 
26 #include "NetdConstants.h"
27 
28 class BandwidthController {
29 public:
30     android::RWLock lock;
31 
32     class TetherStats {
33     public:
TetherStats(void)34         TetherStats(void)
35                 : rxBytes(-1), rxPackets(-1),
36                     txBytes(-1), txPackets(-1) {};
TetherStats(std::string intIfn,std::string extIfn,int64_t rxB,int64_t rxP,int64_t txB,int64_t txP)37         TetherStats(std::string intIfn, std::string extIfn,
38                 int64_t rxB, int64_t rxP,
39                 int64_t txB, int64_t txP)
40                         : intIface(intIfn), extIface(extIfn),
41                             rxBytes(rxB), rxPackets(rxP),
42                             txBytes(txB), txPackets(txP) {};
43         /* Internal interface. Same as NatController's notion. */
44         std::string intIface;
45         /* External interface. Same as NatController's notion. */
46         std::string extIface;
47         int64_t rxBytes, rxPackets;
48         int64_t txBytes, txPackets;
49         /*
50          * Allocates a new string representing this:
51          * intIface extIface rx_bytes rx_packets tx_bytes tx_packets
52          * The caller is responsible for free()'ing the returned ptr.
53          */
54         char *getStatsLine(void) const;
55     };
56 
57     BandwidthController();
58 
59     int setupIptablesHooks(void);
60 
61     int enableBandwidthControl(bool force);
62     int disableBandwidthControl(void);
63     int enableDataSaver(bool enable);
64 
65     int setInterfaceSharedQuota(const char *iface, int64_t bytes);
66     int getInterfaceSharedQuota(int64_t *bytes);
67     int removeInterfaceSharedQuota(const char *iface);
68 
69     int setInterfaceQuota(const char *iface, int64_t bytes);
70     int getInterfaceQuota(const char *iface, int64_t *bytes);
71     int removeInterfaceQuota(const char *iface);
72 
73     int addNaughtyApps(int numUids, char *appUids[]);
74     int removeNaughtyApps(int numUids, char *appUids[]);
75     int addNiceApps(int numUids, char *appUids[]);
76     int removeNiceApps(int numUids, char *appUids[]);
77 
78     int setGlobalAlert(int64_t bytes);
79     int removeGlobalAlert(void);
80     int setGlobalAlertInForwardChain(void);
81     int removeGlobalAlertInForwardChain(void);
82 
83     int setSharedAlert(int64_t bytes);
84     int removeSharedAlert(void);
85 
86     int setInterfaceAlert(const char *iface, int64_t bytes);
87     int removeInterfaceAlert(const char *iface);
88 
89     /*
90      * For single pair of ifaces, stats should have ifaceIn and ifaceOut initialized.
91      * For all pairs, stats should have ifaceIn=ifaceOut="".
92      * Sends out to the cli the single stat (TetheringStatsReluts) or a list of stats
93      * (TetheringStatsListResult+CommandOkay).
94      * Error is to be handled on the outside.
95      * It results in an error if invoked and no tethering counter rules exist.
96      */
97     int getTetherStats(SocketClient *cli, TetherStats &stats, std::string &extraProcessingInfo);
98 
99     static const char* LOCAL_INPUT;
100     static const char* LOCAL_FORWARD;
101     static const char* LOCAL_OUTPUT;
102     static const char* LOCAL_RAW_PREROUTING;
103     static const char* LOCAL_MANGLE_POSTROUTING;
104 
105 protected:
106     class QuotaInfo {
107     public:
QuotaInfo(std::string ifn,int64_t q,int64_t a)108       QuotaInfo(std::string ifn, int64_t q, int64_t a)
109               : ifaceName(ifn), quota(q), alert(a) {};
110         std::string ifaceName;
111         int64_t quota;
112         int64_t alert;
113     };
114 
115     enum IptIpVer { IptIpV4, IptIpV6 };
116     enum IptOp { IptOpInsert, IptOpReplace, IptOpDelete, IptOpAppend };
117     enum IptJumpOp { IptJumpReject, IptJumpReturn, IptJumpNoAdd };
118     enum SpecialAppOp { SpecialAppOpAdd, SpecialAppOpRemove };
119     enum QuotaType { QuotaUnique, QuotaShared };
120     enum RunCmdErrHandling { RunCmdFailureBad, RunCmdFailureOk };
121 #if LOG_NDEBUG
122     enum IptFailureLog { IptFailShow, IptFailHide };
123 #else
124     enum IptFailureLog { IptFailShow, IptFailHide = IptFailShow };
125 #endif
126 
127     int manipulateSpecialApps(int numUids, char *appStrUids[],
128                                const char *chain,
129                                IptJumpOp jumpHandling, SpecialAppOp appOp);
130     int manipulateNaughtyApps(int numUids, char *appStrUids[], SpecialAppOp appOp);
131     int manipulateNiceApps(int numUids, char *appStrUids[], SpecialAppOp appOp);
132 
133     int prepCostlyIface(const char *ifn, QuotaType quotaType);
134     int cleanupCostlyIface(const char *ifn, QuotaType quotaType);
135 
136     std::string makeIptablesSpecialAppCmd(IptOp op, int uid, const char *chain);
137     std::string makeIptablesQuotaCmd(IptOp op, const char *costName, int64_t quota);
138 
139     int runIptablesAlertCmd(IptOp op, const char *alertName, int64_t bytes);
140     int runIptablesAlertFwdCmd(IptOp op, const char *alertName, int64_t bytes);
141 
142     /* Runs for both ipv4 and ipv6 iptables */
143     int runCommands(int numCommands, const char *commands[], RunCmdErrHandling cmdErrHandling);
144     /* Runs for both ipv4 and ipv6 iptables, appends -j REJECT --reject-with ...  */
145     static int runIpxtablesCmd(const char *cmd, IptJumpOp jumpHandling,
146                                IptFailureLog failureHandling = IptFailShow);
147     static int runIptablesCmd(const char *cmd, IptJumpOp jumpHandling, IptIpVer iptIpVer,
148                               IptFailureLog failureHandling = IptFailShow);
149 
150 
151     // Provides strncpy() + check overflow.
152     static int StrncpyAndCheck(char *buffer, const char *src, size_t buffSize);
153 
154     int updateQuota(const char *alertName, int64_t bytes);
155 
156     int setCostlyAlert(const char *costName, int64_t bytes, int64_t *alertBytes);
157     int removeCostlyAlert(const char *costName, int64_t *alertBytes);
158 
159     /*
160      * stats should never have only intIface initialized. Other 3 combos are ok.
161      * fp should be a file to the apropriate FORWARD chain of iptables rules.
162      * extraProcessingInfo: contains raw parsed data, and error info.
163      * This strongly requires that setup of the rules is in a specific order:
164      *  in:intIface out:extIface
165      *  in:extIface out:intIface
166      * and the rules are grouped in pairs when more that one tethering was setup.
167      */
168     static int parseForwardChainStats(SocketClient *cli, const TetherStats filter, FILE *fp,
169                                       std::string &extraProcessingInfo);
170 
171     /*
172      * Attempt to find the bw_costly_* tables that need flushing,
173      * and flush them.
174      * If doClean then remove the tables also.
175      * Deals with both ip4 and ip6 tables.
176      */
177     void flushExistingCostlyTables(bool doClean);
178     static void parseAndFlushCostlyTables(FILE *fp, bool doRemove);
179 
180     /*
181      * Attempt to flush our tables.
182      * If doClean then remove them also.
183      * Deals with both ip4 and ip6 tables.
184      */
185     void flushCleanTables(bool doClean);
186 
187     /*------------------*/
188 
189     std::list<std::string> sharedQuotaIfaces;
190     int64_t sharedQuotaBytes;
191     int64_t sharedAlertBytes;
192     int64_t globalAlertBytes;
193     /*
194      * This tracks the number of tethers setup.
195      * The FORWARD chain is updated in the following cases:
196      *  - The 1st time a globalAlert is setup and there are tethers setup.
197      *  - Anytime a globalAlert is removed and there are tethers setup.
198      *  - The 1st tether is setup and there is a globalAlert active.
199      *  - The last tether is removed and there is a globalAlert active.
200      */
201     int globalAlertTetherCount;
202 
203     std::list<QuotaInfo> quotaIfaces;
204 
205     // For testing.
206     friend class BandwidthControllerTest;
207     static int (*execFunction)(int, char **, int *, bool, bool);
208     static FILE *(*popenFunction)(const char *, const char *);
209     static int (*iptablesRestoreFunction)(IptablesTarget, const std::string&);
210 };
211 
212 #endif
213