diff options
| author | Treehugger Robot <treehugger-gerrit@google.com> | 2021-12-14 08:28:46 +0000 |
|---|---|---|
| committer | Gerrit Code Review <noreply-gerritcodereview@google.com> | 2021-12-14 08:28:46 +0000 |
| commit | 1bb6b56c6b2fda9c0500c3be1a85275e4c75d674 (patch) | |
| tree | 885a15b460e2a5f1e5c989e5dbd630d8b02a39e2 /framework-t/src/android/net/IpSecManager.java | |
| parent | 442f296638339b1aec0af18fb1ec20defa9774b4 (diff) | |
| parent | 8f4e23616c25f06a266196f919dea0e8712da359 (diff) | |
Merge "Move IpSec associated files to f/b/packages/ConnectivityT"
Diffstat (limited to 'framework-t/src/android/net/IpSecManager.java')
| -rw-r--r-- | framework-t/src/android/net/IpSecManager.java | 1034 |
1 files changed, 1034 insertions, 0 deletions
diff --git a/framework-t/src/android/net/IpSecManager.java b/framework-t/src/android/net/IpSecManager.java new file mode 100644 index 0000000000..c10680761f --- /dev/null +++ b/framework-t/src/android/net/IpSecManager.java @@ -0,0 +1,1034 @@ +/* + * Copyright (C) 2017 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package android.net; + +import static android.annotation.SystemApi.Client.MODULE_LIBRARIES; + +import static com.android.internal.util.Preconditions.checkNotNull; + +import android.annotation.NonNull; +import android.annotation.RequiresFeature; +import android.annotation.RequiresPermission; +import android.annotation.SystemApi; +import android.annotation.SystemService; +import android.annotation.TestApi; +import android.content.Context; +import android.content.pm.PackageManager; +import android.net.annotations.PolicyDirection; +import android.os.Binder; +import android.os.ParcelFileDescriptor; +import android.os.RemoteException; +import android.os.ServiceSpecificException; +import android.system.ErrnoException; +import android.system.OsConstants; +import android.util.AndroidException; +import android.util.Log; + +import com.android.internal.annotations.VisibleForTesting; + +import dalvik.system.CloseGuard; + +import java.io.FileDescriptor; +import java.io.IOException; +import java.net.DatagramSocket; +import java.net.InetAddress; +import java.net.Socket; + +/** + * This class contains methods for managing IPsec sessions. Once configured, the kernel will apply + * confidentiality (encryption) and integrity (authentication) to IP traffic. + * + * <p>Note that not all aspects of IPsec are permitted by this API. Applications may create + * transport mode security associations and apply them to individual sockets. Applications looking + * to create an IPsec VPN should use {@link VpnManager} and {@link Ikev2VpnProfile}. + * + * @see <a href="https://tools.ietf.org/html/rfc4301">RFC 4301, Security Architecture for the + * Internet Protocol</a> + */ +@SystemService(Context.IPSEC_SERVICE) +public final class IpSecManager { + private static final String TAG = "IpSecManager"; + + /** + * Used when applying a transform to direct traffic through an {@link IpSecTransform} + * towards the host. + * + * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}. + */ + public static final int DIRECTION_IN = 0; + + /** + * Used when applying a transform to direct traffic through an {@link IpSecTransform} + * away from the host. + * + * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}. + */ + public static final int DIRECTION_OUT = 1; + + /** + * Used when applying a transform to direct traffic through an {@link IpSecTransform} for + * forwarding between interfaces. + * + * <p>See {@link #applyTransportModeTransform(Socket, int, IpSecTransform)}. + * + * @hide + */ + public static final int DIRECTION_FWD = 2; + + /** + * The Security Parameter Index (SPI) 0 indicates an unknown or invalid index. + * + * <p>No IPsec packet may contain an SPI of 0. + * + * @hide + */ + @TestApi public static final int INVALID_SECURITY_PARAMETER_INDEX = 0; + + /** @hide */ + public interface Status { + public static final int OK = 0; + public static final int RESOURCE_UNAVAILABLE = 1; + public static final int SPI_UNAVAILABLE = 2; + } + + /** @hide */ + public static final int INVALID_RESOURCE_ID = -1; + + /** + * Thrown to indicate that a requested SPI is in use. + * + * <p>The combination of remote {@code InetAddress} and SPI must be unique across all apps on + * one device. If this error is encountered, a new SPI is required before a transform may be + * created. This error can be avoided by calling {@link + * IpSecManager#allocateSecurityParameterIndex}. + */ + public static final class SpiUnavailableException extends AndroidException { + private final int mSpi; + + /** + * Construct an exception indicating that a transform with the given SPI is already in use + * or otherwise unavailable. + * + * @param msg description indicating the colliding SPI + * @param spi the SPI that could not be used due to a collision + */ + SpiUnavailableException(String msg, int spi) { + super(msg + " (spi: " + spi + ")"); + mSpi = spi; + } + + /** Get the SPI that caused a collision. */ + public int getSpi() { + return mSpi; + } + } + + /** + * Thrown to indicate that an IPsec resource is unavailable. + * + * <p>This could apply to resources such as sockets, {@link SecurityParameterIndex}, {@link + * IpSecTransform}, or other system resources. If this exception is thrown, users should release + * allocated objects of the type requested. + */ + public static final class ResourceUnavailableException extends AndroidException { + + ResourceUnavailableException(String msg) { + super(msg); + } + } + + private final Context mContext; + private final IIpSecService mService; + + /** + * This class represents a reserved SPI. + * + * <p>Objects of this type are used to track reserved security parameter indices. They can be + * obtained by calling {@link IpSecManager#allocateSecurityParameterIndex} and must be released + * by calling {@link #close()} when they are no longer needed. + */ + public static final class SecurityParameterIndex implements AutoCloseable { + private final IIpSecService mService; + private final InetAddress mDestinationAddress; + private final CloseGuard mCloseGuard = CloseGuard.get(); + private int mSpi = INVALID_SECURITY_PARAMETER_INDEX; + private int mResourceId = INVALID_RESOURCE_ID; + + /** Get the underlying SPI held by this object. */ + public int getSpi() { + return mSpi; + } + + /** + * Release an SPI that was previously reserved. + * + * <p>Release an SPI for use by other users in the system. If a SecurityParameterIndex is + * applied to an IpSecTransform, it will become unusable for future transforms but should + * still be closed to ensure system resources are released. + */ + @Override + public void close() { + try { + mService.releaseSecurityParameterIndex(mResourceId); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } catch (Exception e) { + // On close we swallow all random exceptions since failure to close is not + // actionable by the user. + Log.e(TAG, "Failed to close " + this + ", Exception=" + e); + } finally { + mResourceId = INVALID_RESOURCE_ID; + mCloseGuard.close(); + } + } + + /** Check that the SPI was closed properly. */ + @Override + protected void finalize() throws Throwable { + if (mCloseGuard != null) { + mCloseGuard.warnIfOpen(); + } + + close(); + } + + private SecurityParameterIndex( + @NonNull IIpSecService service, InetAddress destinationAddress, int spi) + throws ResourceUnavailableException, SpiUnavailableException { + mService = service; + mDestinationAddress = destinationAddress; + try { + IpSecSpiResponse result = + mService.allocateSecurityParameterIndex( + destinationAddress.getHostAddress(), spi, new Binder()); + + if (result == null) { + throw new NullPointerException("Received null response from IpSecService"); + } + + int status = result.status; + switch (status) { + case Status.OK: + break; + case Status.RESOURCE_UNAVAILABLE: + throw new ResourceUnavailableException( + "No more SPIs may be allocated by this requester."); + case Status.SPI_UNAVAILABLE: + throw new SpiUnavailableException("Requested SPI is unavailable", spi); + default: + throw new RuntimeException( + "Unknown status returned by IpSecService: " + status); + } + mSpi = result.spi; + mResourceId = result.resourceId; + + if (mSpi == INVALID_SECURITY_PARAMETER_INDEX) { + throw new RuntimeException("Invalid SPI returned by IpSecService: " + status); + } + + if (mResourceId == INVALID_RESOURCE_ID) { + throw new RuntimeException( + "Invalid Resource ID returned by IpSecService: " + status); + } + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + mCloseGuard.open("open"); + } + + /** @hide */ + @VisibleForTesting + public int getResourceId() { + return mResourceId; + } + + @Override + public String toString() { + return new StringBuilder() + .append("SecurityParameterIndex{spi=") + .append(mSpi) + .append(",resourceId=") + .append(mResourceId) + .append("}") + .toString(); + } + } + + /** + * Reserve a random SPI for traffic bound to or from the specified destination address. + * + * <p>If successful, this SPI is guaranteed available until released by a call to {@link + * SecurityParameterIndex#close()}. + * + * @param destinationAddress the destination address for traffic bearing the requested SPI. + * For inbound traffic, the destination should be an address currently assigned on-device. + * @return the reserved SecurityParameterIndex + * @throws {@link #ResourceUnavailableException} indicating that too many SPIs are + * currently allocated for this user + */ + @NonNull + public SecurityParameterIndex allocateSecurityParameterIndex( + @NonNull InetAddress destinationAddress) throws ResourceUnavailableException { + try { + return new SecurityParameterIndex( + mService, + destinationAddress, + IpSecManager.INVALID_SECURITY_PARAMETER_INDEX); + } catch (ServiceSpecificException e) { + throw rethrowUncheckedExceptionFromServiceSpecificException(e); + } catch (SpiUnavailableException unlikely) { + // Because this function allocates a totally random SPI, it really shouldn't ever + // fail to allocate an SPI; we simply need this because the exception is checked. + throw new ResourceUnavailableException("No SPIs available"); + } + } + + /** + * Reserve the requested SPI for traffic bound to or from the specified destination address. + * + * <p>If successful, this SPI is guaranteed available until released by a call to {@link + * SecurityParameterIndex#close()}. + * + * @param destinationAddress the destination address for traffic bearing the requested SPI. + * For inbound traffic, the destination should be an address currently assigned on-device. + * @param requestedSpi the requested SPI. The range 1-255 is reserved and may not be used. See + * RFC 4303 Section 2.1. + * @return the reserved SecurityParameterIndex + * @throws {@link #ResourceUnavailableException} indicating that too many SPIs are + * currently allocated for this user + * @throws {@link #SpiUnavailableException} indicating that the requested SPI could not be + * reserved + */ + @NonNull + public SecurityParameterIndex allocateSecurityParameterIndex( + @NonNull InetAddress destinationAddress, int requestedSpi) + throws SpiUnavailableException, ResourceUnavailableException { + if (requestedSpi == IpSecManager.INVALID_SECURITY_PARAMETER_INDEX) { + throw new IllegalArgumentException("Requested SPI must be a valid (non-zero) SPI"); + } + try { + return new SecurityParameterIndex(mService, destinationAddress, requestedSpi); + } catch (ServiceSpecificException e) { + throw rethrowUncheckedExceptionFromServiceSpecificException(e); + } + } + + /** + * Apply an IPsec transform to a stream socket. + * + * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the + * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When + * the transform is removed from the socket by calling {@link #removeTransportModeTransforms}, + * unprotected traffic can resume on that socket. + * + * <p>For security reasons, the destination address of any traffic on the socket must match the + * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any + * other IP address will result in an IOException. In addition, reads and writes on the socket + * will throw IOException if the user deactivates the transform (by calling {@link + * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}. + * + * <p>Note that when applied to TCP sockets, calling {@link IpSecTransform#close()} on an + * applied transform before completion of graceful shutdown may result in the shutdown sequence + * failing to complete. As such, applications requiring graceful shutdown MUST close the socket + * prior to deactivating the applied transform. Socket closure may be performed asynchronously + * (in batches), so the returning of a close function does not guarantee shutdown of a socket. + * Setting an SO_LINGER timeout results in socket closure being performed synchronously, and is + * sufficient to ensure shutdown. + * + * Specifically, if the transform is deactivated (by calling {@link IpSecTransform#close()}), + * prior to the socket being closed, the standard [FIN - FIN/ACK - ACK], or the reset [RST] + * packets are dropped due to the lack of a valid Transform. Similarly, if a socket without the + * SO_LINGER option set is closed, the delayed/batched FIN packets may be dropped. + * + * <h4>Rekey Procedure</h4> + * + * <p>When applying a new tranform to a socket in the outbound direction, the previous transform + * will be removed and the new transform will take effect immediately, sending all traffic on + * the new transform; however, when applying a transform in the inbound direction, traffic + * on the old transform will continue to be decrypted and delivered until that transform is + * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey + * procedures where both transforms are valid until both endpoints are using the new transform + * and all in-flight packets have been received. + * + * @param socket a stream socket + * @param direction the direction in which the transform should be applied + * @param transform a transport mode {@code IpSecTransform} + * @throws IOException indicating that the transform could not be applied + */ + public void applyTransportModeTransform(@NonNull Socket socket, + @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException { + // Ensure creation of FD. See b/77548890 for more details. + socket.getSoLinger(); + + applyTransportModeTransform(socket.getFileDescriptor$(), direction, transform); + } + + /** + * Apply an IPsec transform to a datagram socket. + * + * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the + * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When + * the transform is removed from the socket by calling {@link #removeTransportModeTransforms}, + * unprotected traffic can resume on that socket. + * + * <p>For security reasons, the destination address of any traffic on the socket must match the + * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any + * other IP address will result in an IOException. In addition, reads and writes on the socket + * will throw IOException if the user deactivates the transform (by calling {@link + * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}. + * + * <h4>Rekey Procedure</h4> + * + * <p>When applying a new tranform to a socket in the outbound direction, the previous transform + * will be removed and the new transform will take effect immediately, sending all traffic on + * the new transform; however, when applying a transform in the inbound direction, traffic + * on the old transform will continue to be decrypted and delivered until that transform is + * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey + * procedures where both transforms are valid until both endpoints are using the new transform + * and all in-flight packets have been received. + * + * @param socket a datagram socket + * @param direction the direction in which the transform should be applied + * @param transform a transport mode {@code IpSecTransform} + * @throws IOException indicating that the transform could not be applied + */ + public void applyTransportModeTransform(@NonNull DatagramSocket socket, + @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException { + applyTransportModeTransform(socket.getFileDescriptor$(), direction, transform); + } + + /** + * Apply an IPsec transform to a socket. + * + * <p>This applies transport mode encapsulation to the given socket. Once applied, I/O on the + * socket will be encapsulated according to the parameters of the {@code IpSecTransform}. When + * the transform is removed from the socket by calling {@link #removeTransportModeTransforms}, + * unprotected traffic can resume on that socket. + * + * <p>For security reasons, the destination address of any traffic on the socket must match the + * remote {@code InetAddress} of the {@code IpSecTransform}. Attempts to send traffic to any + * other IP address will result in an IOException. In addition, reads and writes on the socket + * will throw IOException if the user deactivates the transform (by calling {@link + * IpSecTransform#close()}) without calling {@link #removeTransportModeTransforms}. + * + * <p>Note that when applied to TCP sockets, calling {@link IpSecTransform#close()} on an + * applied transform before completion of graceful shutdown may result in the shutdown sequence + * failing to complete. As such, applications requiring graceful shutdown MUST close the socket + * prior to deactivating the applied transform. Socket closure may be performed asynchronously + * (in batches), so the returning of a close function does not guarantee shutdown of a socket. + * Setting an SO_LINGER timeout results in socket closure being performed synchronously, and is + * sufficient to ensure shutdown. + * + * Specifically, if the transform is deactivated (by calling {@link IpSecTransform#close()}), + * prior to the socket being closed, the standard [FIN - FIN/ACK - ACK], or the reset [RST] + * packets are dropped due to the lack of a valid Transform. Similarly, if a socket without the + * SO_LINGER option set is closed, the delayed/batched FIN packets may be dropped. + * + * <h4>Rekey Procedure</h4> + * + * <p>When applying a new tranform to a socket in the outbound direction, the previous transform + * will be removed and the new transform will take effect immediately, sending all traffic on + * the new transform; however, when applying a transform in the inbound direction, traffic + * on the old transform will continue to be decrypted and delivered until that transform is + * deallocated by calling {@link IpSecTransform#close()}. This overlap allows lossless rekey + * procedures where both transforms are valid until both endpoints are using the new transform + * and all in-flight packets have been received. + * + * @param socket a socket file descriptor + * @param direction the direction in which the transform should be applied + * @param transform a transport mode {@code IpSecTransform} + * @throws IOException indicating that the transform could not be applied + */ + public void applyTransportModeTransform(@NonNull FileDescriptor socket, + @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException { + // We dup() the FileDescriptor here because if we don't, then the ParcelFileDescriptor() + // constructor takes control and closes the user's FD when we exit the method. + try (ParcelFileDescriptor pfd = ParcelFileDescriptor.dup(socket)) { + mService.applyTransportModeTransform(pfd, direction, transform.getResourceId()); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + /** + * Remove an IPsec transform from a stream socket. + * + * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a + * socket allows the socket to be reused for communication in the clear. + * + * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling + * {@link IpSecTransform#close()}, then communication on the socket will fail until this method + * is called. + * + * @param socket a socket that previously had a transform applied to it + * @throws IOException indicating that the transform could not be removed from the socket + */ + public void removeTransportModeTransforms(@NonNull Socket socket) throws IOException { + // Ensure creation of FD. See b/77548890 for more details. + socket.getSoLinger(); + + removeTransportModeTransforms(socket.getFileDescriptor$()); + } + + /** + * Remove an IPsec transform from a datagram socket. + * + * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a + * socket allows the socket to be reused for communication in the clear. + * + * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling + * {@link IpSecTransform#close()}, then communication on the socket will fail until this method + * is called. + * + * @param socket a socket that previously had a transform applied to it + * @throws IOException indicating that the transform could not be removed from the socket + */ + public void removeTransportModeTransforms(@NonNull DatagramSocket socket) throws IOException { + removeTransportModeTransforms(socket.getFileDescriptor$()); + } + + /** + * Remove an IPsec transform from a socket. + * + * <p>Once removed, traffic on the socket will not be encrypted. Removing transforms from a + * socket allows the socket to be reused for communication in the clear. + * + * <p>If an {@code IpSecTransform} object applied to this socket was deallocated by calling + * {@link IpSecTransform#close()}, then communication on the socket will fail until this method + * is called. + * + * @param socket a socket that previously had a transform applied to it + * @throws IOException indicating that the transform could not be removed from the socket + */ + public void removeTransportModeTransforms(@NonNull FileDescriptor socket) throws IOException { + try (ParcelFileDescriptor pfd = ParcelFileDescriptor.dup(socket)) { + mService.removeTransportModeTransforms(pfd); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + /** + * Remove a Tunnel Mode IPsec Transform from a {@link Network}. This must be used as part of + * cleanup if a tunneled Network experiences a change in default route. The Network will drop + * all traffic that cannot be routed to the Tunnel's outbound interface. If that interface is + * lost, all traffic will drop. + * + * <p>TODO: Update javadoc for tunnel mode APIs at the same time the APIs are re-worked. + * + * @param net a network that currently has transform applied to it. + * @param transform a Tunnel Mode IPsec Transform that has been previously applied to the given + * network + * @hide + */ + public void removeTunnelModeTransform(Network net, IpSecTransform transform) {} + + /** + * This class provides access to a UDP encapsulation Socket. + * + * <p>{@code UdpEncapsulationSocket} wraps a system-provided datagram socket intended for IKEv2 + * signalling and UDP encapsulated IPsec traffic. Instances can be obtained by calling {@link + * IpSecManager#openUdpEncapsulationSocket}. The provided socket cannot be re-bound by the + * caller. The caller should not close the {@code FileDescriptor} returned by {@link + * #getFileDescriptor}, but should use {@link #close} instead. + * + * <p>Allowing the user to close or unbind a UDP encapsulation socket could impact the traffic + * of the next user who binds to that port. To prevent this scenario, these sockets are held + * open by the system so that they may only be closed by calling {@link #close} or when the user + * process exits. + */ + public static final class UdpEncapsulationSocket implements AutoCloseable { + private final ParcelFileDescriptor mPfd; + private final IIpSecService mService; + private int mResourceId = INVALID_RESOURCE_ID; + private final int mPort; + private final CloseGuard mCloseGuard = CloseGuard.get(); + + private UdpEncapsulationSocket(@NonNull IIpSecService service, int port) + throws ResourceUnavailableException, IOException { + mService = service; + try { + IpSecUdpEncapResponse result = + mService.openUdpEncapsulationSocket(port, new Binder()); + switch (result.status) { + case Status.OK: + break; + case Status.RESOURCE_UNAVAILABLE: + throw new ResourceUnavailableException( + "No more Sockets may be allocated by this requester."); + default: + throw new RuntimeException( + "Unknown status returned by IpSecService: " + result.status); + } + mResourceId = result.resourceId; + mPort = result.port; + mPfd = result.fileDescriptor; + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + mCloseGuard.open("constructor"); + } + + /** Get the encapsulation socket's file descriptor. */ + public FileDescriptor getFileDescriptor() { + if (mPfd == null) { + return null; + } + return mPfd.getFileDescriptor(); + } + + /** Get the bound port of the wrapped socket. */ + public int getPort() { + return mPort; + } + + /** + * Close this socket. + * + * <p>This closes the wrapped socket. Open encapsulation sockets count against a user's + * resource limits, and forgetting to close them eventually will result in {@link + * ResourceUnavailableException} being thrown. + */ + @Override + public void close() throws IOException { + try { + mService.closeUdpEncapsulationSocket(mResourceId); + mResourceId = INVALID_RESOURCE_ID; + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } catch (Exception e) { + // On close we swallow all random exceptions since failure to close is not + // actionable by the user. + Log.e(TAG, "Failed to close " + this + ", Exception=" + e); + } finally { + mResourceId = INVALID_RESOURCE_ID; + mCloseGuard.close(); + } + + try { + mPfd.close(); + } catch (IOException e) { + Log.e(TAG, "Failed to close UDP Encapsulation Socket with Port= " + mPort); + throw e; + } + } + + /** Check that the socket was closed properly. */ + @Override + protected void finalize() throws Throwable { + if (mCloseGuard != null) { + mCloseGuard.warnIfOpen(); + } + close(); + } + + /** @hide */ + @SystemApi(client = MODULE_LIBRARIES) + public int getResourceId() { + return mResourceId; + } + + @Override + public String toString() { + return new StringBuilder() + .append("UdpEncapsulationSocket{port=") + .append(mPort) + .append(",resourceId=") + .append(mResourceId) + .append("}") + .toString(); + } + }; + + /** + * Open a socket for UDP encapsulation and bind to the given port. + * + * <p>See {@link UdpEncapsulationSocket} for the proper way to close the returned socket. + * + * @param port a local UDP port + * @return a socket that is bound to the given port + * @throws IOException indicating that the socket could not be opened or bound + * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open + */ + // Returning a socket in this fashion that has been created and bound by the system + // is the only safe way to ensure that a socket is both accessible to the user and + // safely usable for Encapsulation without allowing a user to possibly unbind from/close + // the port, which could potentially impact the traffic of the next user who binds to that + // socket. + @NonNull + public UdpEncapsulationSocket openUdpEncapsulationSocket(int port) + throws IOException, ResourceUnavailableException { + /* + * Most range checking is done in the service, but this version of the constructor expects + * a valid port number, and zero cannot be checked after being passed to the service. + */ + if (port == 0) { + throw new IllegalArgumentException("Specified port must be a valid port number!"); + } + try { + return new UdpEncapsulationSocket(mService, port); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } + } + + /** + * Open a socket for UDP encapsulation. + * + * <p>See {@link UdpEncapsulationSocket} for the proper way to close the returned socket. + * + * <p>The local port of the returned socket can be obtained by calling {@link + * UdpEncapsulationSocket#getPort()}. + * + * @return a socket that is bound to a local port + * @throws IOException indicating that the socket could not be opened or bound + * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open + */ + // Returning a socket in this fashion that has been created and bound by the system + // is the only safe way to ensure that a socket is both accessible to the user and + // safely usable for Encapsulation without allowing a user to possibly unbind from/close + // the port, which could potentially impact the traffic of the next user who binds to that + // socket. + @NonNull + public UdpEncapsulationSocket openUdpEncapsulationSocket() + throws IOException, ResourceUnavailableException { + try { + return new UdpEncapsulationSocket(mService, 0); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } + } + + /** + * This class represents an IpSecTunnelInterface + * + * <p>IpSecTunnelInterface objects track tunnel interfaces that serve as + * local endpoints for IPsec tunnels. + * + * <p>Creating an IpSecTunnelInterface creates a device to which IpSecTransforms may be + * applied to provide IPsec security to packets sent through the tunnel. While a tunnel + * cannot be used in standalone mode within Android, the higher layers may use the tunnel + * to create Network objects which are accessible to the Android system. + * @hide + */ + @SystemApi + public static final class IpSecTunnelInterface implements AutoCloseable { + private final String mOpPackageName; + private final IIpSecService mService; + private final InetAddress mRemoteAddress; + private final InetAddress mLocalAddress; + private final Network mUnderlyingNetwork; + private final CloseGuard mCloseGuard = CloseGuard.get(); + private String mInterfaceName; + private int mResourceId = INVALID_RESOURCE_ID; + + /** Get the underlying SPI held by this object. */ + @NonNull + public String getInterfaceName() { + return mInterfaceName; + } + + /** + * Add an address to the IpSecTunnelInterface + * + * <p>Add an address which may be used as the local inner address for + * tunneled traffic. + * + * @param address the local address for traffic inside the tunnel + * @param prefixLen length of the InetAddress prefix + * @hide + */ + @SystemApi + @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS) + @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) + public void addAddress(@NonNull InetAddress address, int prefixLen) throws IOException { + try { + mService.addAddressToTunnelInterface( + mResourceId, new LinkAddress(address, prefixLen), mOpPackageName); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + /** + * Remove an address from the IpSecTunnelInterface + * + * <p>Remove an address which was previously added to the IpSecTunnelInterface + * + * @param address to be removed + * @param prefixLen length of the InetAddress prefix + * @hide + */ + @SystemApi + @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS) + @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) + public void removeAddress(@NonNull InetAddress address, int prefixLen) throws IOException { + try { + mService.removeAddressFromTunnelInterface( + mResourceId, new LinkAddress(address, prefixLen), mOpPackageName); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + /** + * Update the underlying network for this IpSecTunnelInterface. + * + * <p>This new underlying network will be used for all transforms applied AFTER this call is + * complete. Before new {@link IpSecTransform}(s) with matching addresses are applied to + * this tunnel interface, traffic will still use the old SA, and be routed on the old + * underlying network. + * + * <p>To migrate IPsec tunnel mode traffic, a caller should: + * + * <ol> + * <li>Update the IpSecTunnelInterface’s underlying network. + * <li>Apply {@link IpSecTransform}(s) with matching addresses to this + * IpSecTunnelInterface. + * </ol> + * + * @param underlyingNetwork the new {@link Network} that will carry traffic for this tunnel. + * This network MUST never be the network exposing this IpSecTunnelInterface, otherwise + * this method will throw an {@link IllegalArgumentException}. If the + * IpSecTunnelInterface is later added to this network, all outbound traffic will be + * blackholed. + */ + // TODO: b/169171001 Update the documentation when transform migration is supported. + // The purpose of making updating network and applying transforms separate is to leave open + // the possibility to support lossless migration procedures. To do that, Android platform + // will need to support multiple inbound tunnel mode transforms, just like it can support + // multiple transport mode transforms. + @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS) + @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) + public void setUnderlyingNetwork(@NonNull Network underlyingNetwork) throws IOException { + try { + mService.setNetworkForTunnelInterface( + mResourceId, underlyingNetwork, mOpPackageName); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + private IpSecTunnelInterface(@NonNull Context ctx, @NonNull IIpSecService service, + @NonNull InetAddress localAddress, @NonNull InetAddress remoteAddress, + @NonNull Network underlyingNetwork) + throws ResourceUnavailableException, IOException { + mOpPackageName = ctx.getOpPackageName(); + mService = service; + mLocalAddress = localAddress; + mRemoteAddress = remoteAddress; + mUnderlyingNetwork = underlyingNetwork; + + try { + IpSecTunnelInterfaceResponse result = + mService.createTunnelInterface( + localAddress.getHostAddress(), + remoteAddress.getHostAddress(), + underlyingNetwork, + new Binder(), + mOpPackageName); + switch (result.status) { + case Status.OK: + break; + case Status.RESOURCE_UNAVAILABLE: + throw new ResourceUnavailableException( + "No more tunnel interfaces may be allocated by this requester."); + default: + throw new RuntimeException( + "Unknown status returned by IpSecService: " + result.status); + } + mResourceId = result.resourceId; + mInterfaceName = result.interfaceName; + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + mCloseGuard.open("constructor"); + } + + /** + * Delete an IpSecTunnelInterface + * + * <p>Calling close will deallocate the IpSecTunnelInterface and all of its system + * resources. Any packets bound for this interface either inbound or outbound will + * all be lost. + */ + @Override + public void close() { + try { + mService.deleteTunnelInterface(mResourceId, mOpPackageName); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } catch (Exception e) { + // On close we swallow all random exceptions since failure to close is not + // actionable by the user. + Log.e(TAG, "Failed to close " + this + ", Exception=" + e); + } finally { + mResourceId = INVALID_RESOURCE_ID; + mCloseGuard.close(); + } + } + + /** Check that the Interface was closed properly. */ + @Override + protected void finalize() throws Throwable { + if (mCloseGuard != null) { + mCloseGuard.warnIfOpen(); + } + close(); + } + + /** @hide */ + @VisibleForTesting + public int getResourceId() { + return mResourceId; + } + + @NonNull + @Override + public String toString() { + return new StringBuilder() + .append("IpSecTunnelInterface{ifname=") + .append(mInterfaceName) + .append(",resourceId=") + .append(mResourceId) + .append("}") + .toString(); + } + } + + /** + * Create a new IpSecTunnelInterface as a local endpoint for tunneled IPsec traffic. + * + * <p>An application that creates tunnels is responsible for cleaning up the tunnel when the + * underlying network goes away, and the onLost() callback is received. + * + * @param localAddress The local addres of the tunnel + * @param remoteAddress The local addres of the tunnel + * @param underlyingNetwork the {@link Network} that will carry traffic for this tunnel. + * This network should almost certainly be a network such as WiFi with an L2 address. + * @return a new {@link IpSecManager#IpSecTunnelInterface} with the specified properties + * @throws IOException indicating that the socket could not be opened or bound + * @throws ResourceUnavailableException indicating that too many encapsulation sockets are open + * @hide + */ + @SystemApi + @NonNull + @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS) + @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) + public IpSecTunnelInterface createIpSecTunnelInterface(@NonNull InetAddress localAddress, + @NonNull InetAddress remoteAddress, @NonNull Network underlyingNetwork) + throws ResourceUnavailableException, IOException { + try { + return new IpSecTunnelInterface( + mContext, mService, localAddress, remoteAddress, underlyingNetwork); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } + } + + /** + * Apply an active Tunnel Mode IPsec Transform to a {@link IpSecTunnelInterface}, which will + * tunnel all traffic for the given direction through the underlying network's interface with + * IPsec (applies an outer IP header and IPsec Header to all traffic, and expects an additional + * IP header and IPsec Header on all inbound traffic). + * <p>Applications should probably not use this API directly. + * + * + * @param tunnel The {@link IpSecManager#IpSecTunnelInterface} that will use the supplied + * transform. + * @param direction the direction, {@link DIRECTION_OUT} or {@link #DIRECTION_IN} in which + * the transform will be used. + * @param transform an {@link IpSecTransform} created in tunnel mode + * @throws IOException indicating that the transform could not be applied due to a lower + * layer failure. + * @hide + */ + @SystemApi + @RequiresFeature(PackageManager.FEATURE_IPSEC_TUNNELS) + @RequiresPermission(android.Manifest.permission.MANAGE_IPSEC_TUNNELS) + public void applyTunnelModeTransform(@NonNull IpSecTunnelInterface tunnel, + @PolicyDirection int direction, @NonNull IpSecTransform transform) throws IOException { + try { + mService.applyTunnelModeTransform( + tunnel.getResourceId(), direction, + transform.getResourceId(), mContext.getOpPackageName()); + } catch (ServiceSpecificException e) { + throw rethrowCheckedExceptionFromServiceSpecificException(e); + } catch (RemoteException e) { + throw e.rethrowFromSystemServer(); + } + } + + /** + * Construct an instance of IpSecManager within an application context. + * + * @param context the application context for this manager + * @hide + */ + public IpSecManager(Context ctx, IIpSecService service) { + mContext = ctx; + mService = checkNotNull(service, "missing service"); + } + + private static void maybeHandleServiceSpecificException(ServiceSpecificException sse) { + // OsConstants are late binding, so switch statements can't be used. + if (sse.errorCode == OsConstants.EINVAL) { + throw new IllegalArgumentException(sse); + } else if (sse.errorCode == OsConstants.EAGAIN) { + throw new IllegalStateException(sse); + } else if (sse.errorCode == OsConstants.EOPNOTSUPP + || sse.errorCode == OsConstants.EPROTONOSUPPORT) { + throw new UnsupportedOperationException(sse); + } + } + + /** + * Convert an Errno SSE to the correct Unchecked exception type. + * + * This method never actually returns. + */ + // package + static RuntimeException + rethrowUncheckedExceptionFromServiceSpecificException(ServiceSpecificException sse) { + maybeHandleServiceSpecificException(sse); + throw new RuntimeException(sse); + } + + /** + * Convert an Errno SSE to the correct Checked or Unchecked exception type. + * + * This method may throw IOException, or it may throw an unchecked exception; it will never + * actually return. + */ + // package + static IOException rethrowCheckedExceptionFromServiceSpecificException( + ServiceSpecificException sse) throws IOException { + // First see if this is an unchecked exception of a type we know. + // If so, then we prefer the unchecked (specific) type of exception. + maybeHandleServiceSpecificException(sse); + // If not, then all we can do is provide the SSE in the form of an IOException. + throw new ErrnoException( + "IpSec encountered errno=" + sse.errorCode, sse.errorCode).rethrowAsIOException(); + } +} |
