1 /**
2 * Copyright (c) 2016, 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 #define LOG_TAG "Netd"
18
19 #include <vector>
20
21 #include <android-base/stringprintf.h>
22 #include <cutils/log.h>
23 #include <utils/Errors.h>
24 #include <utils/String16.h>
25
26 #include <binder/IPCThreadState.h>
27 #include <binder/IServiceManager.h>
28 #include "android/net/BnNetd.h"
29
30 #include "Controllers.h"
31 #include "DumpWriter.h"
32 #include "NetdConstants.h"
33 #include "NetdNativeService.h"
34 #include "RouteController.h"
35 #include "SockDiag.h"
36 #include "UidRanges.h"
37
38 using android::base::StringPrintf;
39
40 namespace android {
41 namespace net {
42
43 namespace {
44
45 const char CONNECTIVITY_INTERNAL[] = "android.permission.CONNECTIVITY_INTERNAL";
46 const char DUMP[] = "android.permission.DUMP";
47
checkPermission(const char * permission)48 binder::Status checkPermission(const char *permission) {
49 pid_t pid;
50 uid_t uid;
51
52 if (checkCallingPermission(String16(permission), (int32_t *) &pid, (int32_t *) &uid)) {
53 return binder::Status::ok();
54 } else {
55 auto err = StringPrintf("UID %d / PID %d lacks permission %s", uid, pid, permission);
56 return binder::Status::fromExceptionCode(binder::Status::EX_SECURITY, String8(err.c_str()));
57 }
58 }
59
60 #define ENFORCE_PERMISSION(permission) { \
61 binder::Status status = checkPermission((permission)); \
62 if (!status.isOk()) { \
63 return status; \
64 } \
65 }
66
67 #define NETD_LOCKING_RPC(permission, lock) \
68 ENFORCE_PERMISSION(permission); \
69 android::RWLock::AutoWLock _lock(lock);
70
71 #define NETD_BIG_LOCK_RPC(permission) NETD_LOCKING_RPC((permission), gBigNetdLock)
72 } // namespace
73
74
start()75 status_t NetdNativeService::start() {
76 IPCThreadState::self()->disableBackgroundScheduling(true);
77 status_t ret = BinderService<NetdNativeService>::publish();
78 if (ret != android::OK) {
79 return ret;
80 }
81 sp<ProcessState> ps(ProcessState::self());
82 ps->startThreadPool();
83 ps->giveThreadPoolName();
84 return android::OK;
85 }
86
dump(int fd,const Vector<String16> &)87 status_t NetdNativeService::dump(int fd, const Vector<String16> & /* args */) {
88 const binder::Status dump_permission = checkPermission(DUMP);
89 if (!dump_permission.isOk()) {
90 const String8 msg(dump_permission.toString8());
91 write(fd, msg.string(), msg.size());
92 return PERMISSION_DENIED;
93 }
94
95 // This method does not grab any locks. If individual classes need locking
96 // their dump() methods MUST handle locking appropriately.
97 DumpWriter dw(fd);
98 dw.blankline();
99 gCtls->netCtrl.dump(dw);
100 dw.blankline();
101
102 return NO_ERROR;
103 }
104
isAlive(bool * alive)105 binder::Status NetdNativeService::isAlive(bool *alive) {
106 NETD_BIG_LOCK_RPC(CONNECTIVITY_INTERNAL);
107
108 *alive = true;
109 return binder::Status::ok();
110 }
111
firewallReplaceUidChain(const android::String16 & chainName,bool isWhitelist,const std::vector<int32_t> & uids,bool * ret)112 binder::Status NetdNativeService::firewallReplaceUidChain(const android::String16& chainName,
113 bool isWhitelist, const std::vector<int32_t>& uids, bool *ret) {
114 NETD_LOCKING_RPC(CONNECTIVITY_INTERNAL, gCtls->firewallCtrl.lock);
115
116 android::String8 name = android::String8(chainName);
117 int err = gCtls->firewallCtrl.replaceUidChain(name.string(), isWhitelist, uids);
118 *ret = (err == 0);
119 return binder::Status::ok();
120 }
121
bandwidthEnableDataSaver(bool enable,bool * ret)122 binder::Status NetdNativeService::bandwidthEnableDataSaver(bool enable, bool *ret) {
123 NETD_LOCKING_RPC(CONNECTIVITY_INTERNAL, gCtls->bandwidthCtrl.lock);
124
125 int err = gCtls->bandwidthCtrl.enableDataSaver(enable);
126 *ret = (err == 0);
127 return binder::Status::ok();
128 }
129
networkRejectNonSecureVpn(bool add,const std::vector<UidRange> & uidRangeArray)130 binder::Status NetdNativeService::networkRejectNonSecureVpn(bool add,
131 const std::vector<UidRange>& uidRangeArray) {
132 // TODO: elsewhere RouteController is only used from the tethering and network controllers, so
133 // it should be possible to use the same lock as NetworkController. However, every call through
134 // the CommandListener "network" command will need to hold this lock too, not just the ones that
135 // read/modify network internal state (that is sufficient for ::dump() because it doesn't
136 // look at routes, but it's not enough here).
137 NETD_BIG_LOCK_RPC(CONNECTIVITY_INTERNAL);
138
139 UidRanges uidRanges(uidRangeArray);
140
141 int err;
142 if (add) {
143 err = RouteController::addUsersToRejectNonSecureNetworkRule(uidRanges);
144 } else {
145 err = RouteController::removeUsersFromRejectNonSecureNetworkRule(uidRanges);
146 }
147
148 if (err != 0) {
149 return binder::Status::fromServiceSpecificError(-err,
150 String8::format("RouteController error: %s", strerror(-err)));
151 }
152 return binder::Status::ok();
153 }
154
socketDestroy(const std::vector<UidRange> & uids,const std::vector<int32_t> & skipUids)155 binder::Status NetdNativeService::socketDestroy(const std::vector<UidRange>& uids,
156 const std::vector<int32_t>& skipUids) {
157
158 ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
159
160 SockDiag sd;
161 if (!sd.open()) {
162 return binder::Status::fromServiceSpecificError(EIO,
163 String8("Could not open SOCK_DIAG socket"));
164 }
165
166 UidRanges uidRanges(uids);
167 int err = sd.destroySockets(uidRanges, std::set<uid_t>(skipUids.begin(), skipUids.end()),
168 true /* excludeLoopback */);
169
170 if (err) {
171 return binder::Status::fromServiceSpecificError(-err,
172 String8::format("destroySockets: %s", strerror(-err)));
173 }
174 return binder::Status::ok();
175 }
176
setResolverConfiguration(int32_t netId,const std::vector<std::string> & servers,const std::vector<std::string> & domains,const std::vector<int32_t> & params)177 binder::Status NetdNativeService::setResolverConfiguration(int32_t netId,
178 const std::vector<std::string>& servers, const std::vector<std::string>& domains,
179 const std::vector<int32_t>& params) {
180 // This function intentionally does not lock within Netd, as Bionic is thread-safe.
181 ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
182
183 int err = gCtls->resolverCtrl.setResolverConfiguration(netId, servers, domains, params);
184 if (err != 0) {
185 return binder::Status::fromServiceSpecificError(-err,
186 String8::format("ResolverController error: %s", strerror(-err)));
187 }
188 return binder::Status::ok();
189 }
190
getResolverInfo(int32_t netId,std::vector<std::string> * servers,std::vector<std::string> * domains,std::vector<int32_t> * params,std::vector<int32_t> * stats)191 binder::Status NetdNativeService::getResolverInfo(int32_t netId,
192 std::vector<std::string>* servers, std::vector<std::string>* domains,
193 std::vector<int32_t>* params, std::vector<int32_t>* stats) {
194 // This function intentionally does not lock within Netd, as Bionic is thread-safe.
195 ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
196
197 int err = gCtls->resolverCtrl.getResolverInfo(netId, servers, domains, params, stats);
198 if (err != 0) {
199 return binder::Status::fromServiceSpecificError(-err,
200 String8::format("ResolverController error: %s", strerror(-err)));
201 }
202 return binder::Status::ok();
203 }
204
tetherApplyDnsInterfaces(bool * ret)205 binder::Status NetdNativeService::tetherApplyDnsInterfaces(bool *ret) {
206 NETD_BIG_LOCK_RPC(CONNECTIVITY_INTERNAL);
207
208 *ret = gCtls->tetherCtrl.applyDnsInterfaces();
209 return binder::Status::ok();
210 }
211
interfaceAddAddress(const std::string & ifName,const std::string & addrString,int prefixLength)212 binder::Status NetdNativeService::interfaceAddAddress(const std::string &ifName,
213 const std::string &addrString, int prefixLength) {
214 ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
215
216 const int err = InterfaceController::addAddress(
217 ifName.c_str(), addrString.c_str(), prefixLength);
218 if (err != 0) {
219 return binder::Status::fromServiceSpecificError(-err,
220 String8::format("InterfaceController error: %s", strerror(-err)));
221 }
222 return binder::Status::ok();
223 }
224
interfaceDelAddress(const std::string & ifName,const std::string & addrString,int prefixLength)225 binder::Status NetdNativeService::interfaceDelAddress(const std::string &ifName,
226 const std::string &addrString, int prefixLength) {
227 ENFORCE_PERMISSION(CONNECTIVITY_INTERNAL);
228
229 const int err = InterfaceController::delAddress(
230 ifName.c_str(), addrString.c_str(), prefixLength);
231 if (err != 0) {
232 return binder::Status::fromServiceSpecificError(-err,
233 String8::format("InterfaceController error: %s", strerror(-err)));
234 }
235 return binder::Status::ok();
236 }
237
238 } // namespace net
239 } // namespace android
240