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 #include "PhysicalNetwork.h" 18 19 #include "RouteController.h" 20 #include "SockDiag.h" 21 22 #define LOG_TAG "Netd" 23 #include "log/log.h" 24 25 namespace android { 26 namespace net { 27 28 namespace { 29 30 WARN_UNUSED_RESULT int addToDefault(unsigned netId, const std::string& interface, 31 Permission permission, PhysicalNetwork::Delegate* delegate) { 32 if (int ret = RouteController::addInterfaceToDefaultNetwork(interface.c_str(), permission)) { 33 ALOGE("failed to add interface %s to default netId %u", interface.c_str(), netId); 34 return ret; 35 } 36 if (int ret = delegate->addFallthrough(interface, permission)) { 37 return ret; 38 } 39 return 0; 40 } 41 42 WARN_UNUSED_RESULT int removeFromDefault(unsigned netId, const std::string& interface, 43 Permission permission, 44 PhysicalNetwork::Delegate* delegate) { 45 if (int ret = RouteController::removeInterfaceFromDefaultNetwork(interface.c_str(), 46 permission)) { 47 ALOGE("failed to remove interface %s from default netId %u", interface.c_str(), netId); 48 return ret; 49 } 50 if (int ret = delegate->removeFallthrough(interface, permission)) { 51 return ret; 52 } 53 return 0; 54 } 55 56 } // namespace 57 58 PhysicalNetwork::Delegate::~Delegate() { 59 } 60 61 PhysicalNetwork::PhysicalNetwork(unsigned netId, PhysicalNetwork::Delegate* delegate) : 62 Network(netId), mDelegate(delegate), mPermission(PERMISSION_NONE), mIsDefault(false) { 63 } 64 65 PhysicalNetwork::~PhysicalNetwork() { 66 } 67 68 Permission PhysicalNetwork::getPermission() const { 69 return mPermission; 70 } 71 72 int PhysicalNetwork::destroySocketsLackingPermission(Permission permission) { 73 if (permission == PERMISSION_NONE) return 0; 74 75 SockDiag sd; 76 if (!sd.open()) { 77 ALOGE("Error closing sockets for netId %d permission change", mNetId); 78 return -EBADFD; 79 } 80 if (int ret = sd.destroySocketsLackingPermission(mNetId, permission, 81 true /* excludeLoopback */)) { 82 ALOGE("Failed to close sockets changing netId %d to permission %d: %s", 83 mNetId, permission, strerror(-ret)); 84 return ret; 85 } 86 return 0; 87 } 88 89 void PhysicalNetwork::invalidateRouteCache(const std::string& interface) { 90 for (const auto& dst : { "0.0.0.0/0", "::/0" }) { 91 // If any of these operations fail, there's no point in logging because RouteController will 92 // have already logged a message. There's also no point returning an error since there's 93 // nothing we can do. 94 (void) RouteController::addRoute(interface.c_str(), dst, "throw", 95 RouteController::INTERFACE); 96 (void) RouteController::removeRoute(interface.c_str(), dst, "throw", 97 RouteController::INTERFACE); 98 } 99 } 100 101 int PhysicalNetwork::setPermission(Permission permission) { 102 if (permission == mPermission) { 103 return 0; 104 } 105 if (mInterfaces.empty()) { 106 mPermission = permission; 107 return 0; 108 } 109 110 destroySocketsLackingPermission(permission); 111 for (const std::string& interface : mInterfaces) { 112 if (int ret = RouteController::modifyPhysicalNetworkPermission(mNetId, interface.c_str(), 113 mPermission, permission)) { 114 ALOGE("failed to change permission on interface %s of netId %u from %x to %x", 115 interface.c_str(), mNetId, mPermission, permission); 116 return ret; 117 } 118 invalidateRouteCache(interface); 119 } 120 if (mIsDefault) { 121 for (const std::string& interface : mInterfaces) { 122 if (int ret = addToDefault(mNetId, interface, permission, mDelegate)) { 123 return ret; 124 } 125 if (int ret = removeFromDefault(mNetId, interface, mPermission, mDelegate)) { 126 return ret; 127 } 128 } 129 } 130 // Destroy sockets again in case any were opened after we called destroySocketsLackingPermission 131 // above and before we changed the permissions. These sockets won't be able to send any RST 132 // packets because they are now no longer routed, but at least the apps will get errors. 133 destroySocketsLackingPermission(permission); 134 mPermission = permission; 135 return 0; 136 } 137 138 int PhysicalNetwork::addAsDefault() { 139 if (mIsDefault) { 140 return 0; 141 } 142 for (const std::string& interface : mInterfaces) { 143 if (int ret = addToDefault(mNetId, interface, mPermission, mDelegate)) { 144 return ret; 145 } 146 } 147 mIsDefault = true; 148 return 0; 149 } 150 151 int PhysicalNetwork::removeAsDefault() { 152 if (!mIsDefault) { 153 return 0; 154 } 155 for (const std::string& interface : mInterfaces) { 156 if (int ret = removeFromDefault(mNetId, interface, mPermission, mDelegate)) { 157 return ret; 158 } 159 } 160 mIsDefault = false; 161 return 0; 162 } 163 164 Network::Type PhysicalNetwork::getType() const { 165 return PHYSICAL; 166 } 167 168 int PhysicalNetwork::addInterface(const std::string& interface) { 169 if (hasInterface(interface)) { 170 return 0; 171 } 172 if (int ret = RouteController::addInterfaceToPhysicalNetwork(mNetId, interface.c_str(), 173 mPermission)) { 174 ALOGE("failed to add interface %s to netId %u", interface.c_str(), mNetId); 175 return ret; 176 } 177 if (mIsDefault) { 178 if (int ret = addToDefault(mNetId, interface, mPermission, mDelegate)) { 179 return ret; 180 } 181 } 182 mInterfaces.insert(interface); 183 return 0; 184 } 185 186 int PhysicalNetwork::removeInterface(const std::string& interface) { 187 if (!hasInterface(interface)) { 188 return 0; 189 } 190 if (mIsDefault) { 191 if (int ret = removeFromDefault(mNetId, interface, mPermission, mDelegate)) { 192 return ret; 193 } 194 } 195 // This step will flush the interface index from the cache in RouteController so it must be 196 // done last as further requests to the RouteController regarding this interface will fail 197 // to find the interface index in the cache in cases where the interface is already gone 198 // (e.g. bt-pan). 199 if (int ret = RouteController::removeInterfaceFromPhysicalNetwork(mNetId, interface.c_str(), 200 mPermission)) { 201 ALOGE("failed to remove interface %s from netId %u", interface.c_str(), mNetId); 202 return ret; 203 } 204 mInterfaces.erase(interface); 205 return 0; 206 } 207 208 } // namespace net 209 } // namespace android 210
