NetworkController.h revision 87475a1471373b72ffc9f81f17dfd7884723fa86 
1/*
2 * Copyright (C) 2014 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_NETWORK_CONTROLLER_H
18#define NETD_SERVER_NETWORK_CONTROLLER_H
19
20#include "NetdConstants.h"
21#include "Permission.h"
22
23#include "utils/RWLock.h"
24
25#include <list>
26#include <map>
27#include <set>
28#include <sys/types.h>
29#include <vector>
30
31class Network;
32class UidRanges;
33class VirtualNetwork;
34
35/*
36 * Keeps track of default, per-pid, and per-uid-range network selection, as
37 * well as the mark associated with each network. Networks are identified
38 * by netid. In all set* commands netid == 0 means "unspecified" and is
39 * equivalent to clearing the mapping.
40 */
41class NetworkController {
42public:
43    static const int LOCAL_NET_ID = 9;
44
45    NetworkController();
46
47    unsigned getDefaultNetwork() const;
48    int setDefaultNetwork(unsigned netId) WARN_UNUSED_RESULT;
49
50    // Order of preference: UID-specific, requestedNetId, default.
51    // Specify NETID_UNSET for requestedNetId if the default network is preferred.
52    // forDns indicates if we're querying the netId for a DNS request. This avoids sending DNS
53    // requests to VPNs without DNS servers.
54    unsigned getNetworkForUser(uid_t uid, unsigned requestedNetId, bool forDns) const;
55    unsigned getNetworkForInterface(const char* interface) const;
56    bool isVirtualNetwork(unsigned netId) const;
57
58    int createPhysicalNetwork(unsigned netId, Permission permission) WARN_UNUSED_RESULT;
59    int createVirtualNetwork(unsigned netId, bool hasDns) WARN_UNUSED_RESULT;
60    int destroyNetwork(unsigned netId) WARN_UNUSED_RESULT;
61
62    int addInterfaceToNetwork(unsigned netId, const char* interface) WARN_UNUSED_RESULT;
63    int removeInterfaceFromNetwork(unsigned netId, const char* interface) WARN_UNUSED_RESULT;
64
65    Permission getPermissionForUser(uid_t uid) const;
66    void setPermissionForUsers(Permission permission, const std::vector<uid_t>& uids);
67    bool canUserSelectNetwork(uid_t uid, unsigned netId) const;
68    int setPermissionForNetworks(Permission permission,
69                                 const std::vector<unsigned>& netIds) WARN_UNUSED_RESULT;
70
71    int addUsersToNetwork(unsigned netId, const UidRanges& uidRanges) WARN_UNUSED_RESULT;
72    int removeUsersFromNetwork(unsigned netId, const UidRanges& uidRanges) WARN_UNUSED_RESULT;
73
74    // Routes are added to tables determined by the interface, so only |interface| is actually used.
75    // |netId| is given only to sanity check that the interface has the correct netId.
76    int addRoute(unsigned netId, const char* interface, const char* destination,
77                 const char* nexthop, bool legacy, uid_t uid) WARN_UNUSED_RESULT;
78    int removeRoute(unsigned netId, const char* interface, const char* destination,
79                    const char* nexthop, bool legacy, uid_t uid) WARN_UNUSED_RESULT;
80
81    bool canProtect(uid_t uid) const;
82    void allowProtect(const std::vector<uid_t>& uids);
83    void denyProtect(const std::vector<uid_t>& uids);
84
85private:
86    bool isValidNetwork(unsigned netId) const;
87    Network* getNetworkLocked(unsigned netId) const;
88    VirtualNetwork* getVirtualNetworkForUserLocked(uid_t uid) const;
89    Permission getPermissionForUserLocked(uid_t uid) const;
90
91    int modifyRoute(unsigned netId, const char* interface, const char* destination,
92                    const char* nexthop, bool add, bool legacy, uid_t uid) WARN_UNUSED_RESULT;
93
94    // mRWLock guards all accesses to mDefaultNetId, mNetworks, mUsers and mProtectableUsers.
95    mutable android::RWLock mRWLock;
96    unsigned mDefaultNetId;
97    std::map<unsigned, Network*> mNetworks;  // Map keys are NetIds.
98    std::map<uid_t, Permission> mUsers;
99    std::set<uid_t> mProtectableUsers;
100};
101
102#endif  // NETD_SERVER_NETWORK_CONTROLLER_H
103