1 /* 2 * Copyright (C) 2008 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 package android.net; 18 19 import android.os.SystemProperties; 20 import android.util.Log; 21 import com.android.org.conscrypt.OpenSSLContextImpl; 22 import com.android.org.conscrypt.OpenSSLSocketImpl; 23 import com.android.org.conscrypt.SSLClientSessionCache; 24 import java.io.IOException; 25 import java.net.InetAddress; 26 import java.net.Socket; 27 import java.net.SocketException; 28 import java.security.KeyManagementException; 29 import java.security.PrivateKey; 30 import java.security.cert.X509Certificate; 31 import javax.net.SocketFactory; 32 import javax.net.ssl.HostnameVerifier; 33 import javax.net.ssl.HttpsURLConnection; 34 import javax.net.ssl.KeyManager; 35 import javax.net.ssl.SSLException; 36 import javax.net.ssl.SSLPeerUnverifiedException; 37 import javax.net.ssl.SSLSession; 38 import javax.net.ssl.SSLSocket; 39 import javax.net.ssl.SSLSocketFactory; 40 import javax.net.ssl.TrustManager; 41 import javax.net.ssl.X509TrustManager; 42 43 /** 44 * SSLSocketFactory implementation with several extra features: 45 * 46 * <ul> 47 * <li>Timeout specification for SSL handshake operations 48 * <li>Hostname verification in most cases (see WARNINGs below) 49 * <li>Optional SSL session caching with {@link SSLSessionCache} 50 * <li>Optionally bypass all SSL certificate checks 51 * </ul> 52 * 53 * The handshake timeout does not apply to actual TCP socket connection. 54 * If you want a connection timeout as well, use {@link #createSocket()} 55 * and {@link Socket#connect(SocketAddress, int)}, after which you 56 * must verify the identity of the server you are connected to. 57 * 58 * <p class="caution"><b>Most {@link SSLSocketFactory} implementations do not 59 * verify the server's identity, allowing man-in-the-middle attacks.</b> 60 * This implementation does check the server's certificate hostname, but only 61 * for createSocket variants that specify a hostname. When using methods that 62 * use {@link InetAddress} or which return an unconnected socket, you MUST 63 * verify the server's identity yourself to ensure a secure connection.</p> 64 * 65 * <p>One way to verify the server's identity is to use 66 * {@link HttpsURLConnection#getDefaultHostnameVerifier()} to get a 67 * {@link HostnameVerifier} to verify the certificate hostname. 68 * 69 * <p>On development devices, "setprop socket.relaxsslcheck yes" bypasses all 70 * SSL certificate and hostname checks for testing purposes. This setting 71 * requires root access. 72 */ 73 public class SSLCertificateSocketFactory extends SSLSocketFactory { 74 private static final String TAG = "SSLCertificateSocketFactory"; 75 76 private static final TrustManager[] INSECURE_TRUST_MANAGER = new TrustManager[] { 77 new X509TrustManager() { 78 public X509Certificate[] getAcceptedIssuers() { return null; } 79 public void checkClientTrusted(X509Certificate[] certs, String authType) { } 80 public void checkServerTrusted(X509Certificate[] certs, String authType) { } 81 } 82 }; 83 84 private SSLSocketFactory mInsecureFactory = null; 85 private SSLSocketFactory mSecureFactory = null; 86 private TrustManager[] mTrustManagers = null; 87 private KeyManager[] mKeyManagers = null; 88 private byte[] mNpnProtocols = null; 89 private byte[] mAlpnProtocols = null; 90 private PrivateKey mChannelIdPrivateKey = null; 91 92 private final int mHandshakeTimeoutMillis; 93 private final SSLClientSessionCache mSessionCache; 94 private final boolean mSecure; 95 96 /** @deprecated Use {@link #getDefault(int)} instead. */ 97 @Deprecated 98 public SSLCertificateSocketFactory(int handshakeTimeoutMillis) { 99 this(handshakeTimeoutMillis, null, true); 100 } 101 102 private SSLCertificateSocketFactory( 103 int handshakeTimeoutMillis, SSLSessionCache cache, boolean secure) { 104 mHandshakeTimeoutMillis = handshakeTimeoutMillis; 105 mSessionCache = cache == null ? null : cache.mSessionCache; 106 mSecure = secure; 107 } 108 109 /** 110 * Returns a new socket factory instance with an optional handshake timeout. 111 * 112 * @param handshakeTimeoutMillis to use for SSL connection handshake, or 0 113 * for none. The socket timeout is reset to 0 after the handshake. 114 * @return a new SSLSocketFactory with the specified parameters 115 */ 116 public static SocketFactory getDefault(int handshakeTimeoutMillis) { 117 return new SSLCertificateSocketFactory(handshakeTimeoutMillis, null, true); 118 } 119 120 /** 121 * Returns a new socket factory instance with an optional handshake timeout 122 * and SSL session cache. 123 * 124 * @param handshakeTimeoutMillis to use for SSL connection handshake, or 0 125 * for none. The socket timeout is reset to 0 after the handshake. 126 * @param cache The {@link SSLSessionCache} to use, or null for no cache. 127 * @return a new SSLSocketFactory with the specified parameters 128 */ 129 public static SSLSocketFactory getDefault(int handshakeTimeoutMillis, SSLSessionCache cache) { 130 return new SSLCertificateSocketFactory(handshakeTimeoutMillis, cache, true); 131 } 132 133 /** 134 * Returns a new instance of a socket factory with all SSL security checks 135 * disabled, using an optional handshake timeout and SSL session cache. 136 * 137 * <p class="caution"><b>Warning:</b> Sockets created using this factory 138 * are vulnerable to man-in-the-middle attacks!</p> 139 * 140 * @param handshakeTimeoutMillis to use for SSL connection handshake, or 0 141 * for none. The socket timeout is reset to 0 after the handshake. 142 * @param cache The {@link SSLSessionCache} to use, or null for no cache. 143 * @return an insecure SSLSocketFactory with the specified parameters 144 */ 145 public static SSLSocketFactory getInsecure(int handshakeTimeoutMillis, SSLSessionCache cache) { 146 return new SSLCertificateSocketFactory(handshakeTimeoutMillis, cache, false); 147 } 148 149 /** 150 * Returns a socket factory (also named SSLSocketFactory, but in a different 151 * namespace) for use with the Apache HTTP stack. 152 * 153 * @param handshakeTimeoutMillis to use for SSL connection handshake, or 0 154 * for none. The socket timeout is reset to 0 after the handshake. 155 * @param cache The {@link SSLSessionCache} to use, or null for no cache. 156 * @return a new SocketFactory with the specified parameters 157 */ 158 public static org.apache.http.conn.ssl.SSLSocketFactory getHttpSocketFactory( 159 int handshakeTimeoutMillis, SSLSessionCache cache) { 160 return new org.apache.http.conn.ssl.SSLSocketFactory( 161 new SSLCertificateSocketFactory(handshakeTimeoutMillis, cache, true)); 162 } 163 164 /** 165 * Verify the hostname of the certificate used by the other end of a 166 * connected socket. You MUST call this if you did not supply a hostname 167 * to {@link #createSocket()}. It is harmless to call this method 168 * redundantly if the hostname has already been verified. 169 * 170 * <p>Wildcard certificates are allowed to verify any matching hostname, 171 * so "foo.bar.example.com" is verified if the peer has a certificate 172 * for "*.example.com". 173 * 174 * @param socket An SSL socket which has been connected to a server 175 * @param hostname The expected hostname of the remote server 176 * @throws IOException if something goes wrong handshaking with the server 177 * @throws SSLPeerUnverifiedException if the server cannot prove its identity 178 * 179 * @hide 180 */ 181 public static void verifyHostname(Socket socket, String hostname) throws IOException { 182 if (!(socket instanceof SSLSocket)) { 183 throw new IllegalArgumentException("Attempt to verify non-SSL socket"); 184 } 185 186 if (!isSslCheckRelaxed()) { 187 // The code at the start of OpenSSLSocketImpl.startHandshake() 188 // ensures that the call is idempotent, so we can safely call it. 189 SSLSocket ssl = (SSLSocket) socket; 190 ssl.startHandshake(); 191 192 SSLSession session = ssl.getSession(); 193 if (session == null) { 194 throw new SSLException("Cannot verify SSL socket without session"); 195 } 196 if (!HttpsURLConnection.getDefaultHostnameVerifier().verify(hostname, session)) { 197 throw new SSLPeerUnverifiedException("Cannot verify hostname: " + hostname); 198 } 199 } 200 } 201 202 private SSLSocketFactory makeSocketFactory( 203 KeyManager[] keyManagers, TrustManager[] trustManagers) { 204 try { 205 OpenSSLContextImpl sslContext = new OpenSSLContextImpl(); 206 sslContext.engineInit(keyManagers, trustManagers, null); 207 sslContext.engineGetClientSessionContext().setPersistentCache(mSessionCache); 208 return sslContext.engineGetSocketFactory(); 209 } catch (KeyManagementException e) { 210 Log.wtf(TAG, e); 211 return (SSLSocketFactory) SSLSocketFactory.getDefault(); // Fallback 212 } 213 } 214 215 private static boolean isSslCheckRelaxed() { 216 return "1".equals(SystemProperties.get("ro.debuggable")) && 217 "yes".equals(SystemProperties.get("socket.relaxsslcheck")); 218 } 219 220 private synchronized SSLSocketFactory getDelegate() { 221 // Relax the SSL check if instructed (for this factory, or systemwide) 222 if (!mSecure || isSslCheckRelaxed()) { 223 if (mInsecureFactory == null) { 224 if (mSecure) { 225 Log.w(TAG, "*** BYPASSING SSL SECURITY CHECKS (socket.relaxsslcheck=yes) ***"); 226 } else { 227 Log.w(TAG, "Bypassing SSL security checks at caller's request"); 228 } 229 mInsecureFactory = makeSocketFactory(mKeyManagers, INSECURE_TRUST_MANAGER); 230 } 231 return mInsecureFactory; 232 } else { 233 if (mSecureFactory == null) { 234 mSecureFactory = makeSocketFactory(mKeyManagers, mTrustManagers); 235 } 236 return mSecureFactory; 237 } 238 } 239 240 /** 241 * Sets the {@link TrustManager}s to be used for connections made by this factory. 242 */ 243 public void setTrustManagers(TrustManager[] trustManager) { 244 mTrustManagers = trustManager; 245 246 // Clear out all cached secure factories since configurations have changed. 247 mSecureFactory = null; 248 // Note - insecure factories only ever use the INSECURE_TRUST_MANAGER so they need not 249 // be cleared out here. 250 } 251 252 /** 253 * Sets the <a href="http://technotes.googlecode.com/git/nextprotoneg.html">Next 254 * Protocol Negotiation (NPN)</a> protocols that this peer is interested in. 255 * 256 * <p>For servers this is the sequence of protocols to advertise as 257 * supported, in order of preference. This list is sent unencrypted to 258 * all clients that support NPN. 259 * 260 * <p>For clients this is a list of supported protocols to match against the 261 * server's list. If there is no protocol supported by both client and 262 * server then the first protocol in the client's list will be selected. 263 * The order of the client's protocols is otherwise insignificant. 264 * 265 * @param npnProtocols a non-empty list of protocol byte arrays. All arrays 266 * must be non-empty and of length less than 256. 267 */ 268 public void setNpnProtocols(byte[][] npnProtocols) { 269 this.mNpnProtocols = toLengthPrefixedList(npnProtocols); 270 } 271 272 /** 273 * Sets the 274 * <a href="http://tools.ietf.org/html/draft-ietf-tls-applayerprotoneg-01"> 275 * Application Layer Protocol Negotiation (ALPN)</a> protocols that this peer 276 * is interested in. 277 * 278 * <p>For servers this is the sequence of protocols to advertise as 279 * supported, in order of preference. This list is sent unencrypted to 280 * all clients that support ALPN. 281 * 282 * <p>For clients this is a list of supported protocols to match against the 283 * server's list. If there is no protocol supported by both client and 284 * server then the first protocol in the client's list will be selected. 285 * The order of the client's protocols is otherwise insignificant. 286 * 287 * @param protocols a non-empty list of protocol byte arrays. All arrays 288 * must be non-empty and of length less than 256. 289 * @hide 290 */ 291 public void setAlpnProtocols(byte[][] protocols) { 292 this.mAlpnProtocols = toLengthPrefixedList(protocols); 293 } 294 295 /** 296 * Returns an array containing the concatenation of length-prefixed byte 297 * strings. 298 */ 299 static byte[] toLengthPrefixedList(byte[]... items) { 300 if (items.length == 0) { 301 throw new IllegalArgumentException("items.length == 0"); 302 } 303 int totalLength = 0; 304 for (byte[] s : items) { 305 if (s.length == 0 || s.length > 255) { 306 throw new IllegalArgumentException("s.length == 0 || s.length > 255: " + s.length); 307 } 308 totalLength += 1 + s.length; 309 } 310 byte[] result = new byte[totalLength]; 311 int pos = 0; 312 for (byte[] s : items) { 313 result[pos++] = (byte) s.length; 314 for (byte b : s) { 315 result[pos++] = b; 316 } 317 } 318 return result; 319 } 320 321 /** 322 * Returns the <a href="http://technotes.googlecode.com/git/nextprotoneg.html">Next 323 * Protocol Negotiation (NPN)</a> protocol selected by client and server, or 324 * null if no protocol was negotiated. 325 * 326 * @param socket a socket created by this factory. 327 * @throws IllegalArgumentException if the socket was not created by this factory. 328 */ 329 public byte[] getNpnSelectedProtocol(Socket socket) { 330 return castToOpenSSLSocket(socket).getNpnSelectedProtocol(); 331 } 332 333 /** 334 * Returns the 335 * <a href="http://tools.ietf.org/html/draft-ietf-tls-applayerprotoneg-01">Application 336 * Layer Protocol Negotiation (ALPN)</a> protocol selected by client and server, or null 337 * if no protocol was negotiated. 338 * 339 * @param socket a socket created by this factory. 340 * @throws IllegalArgumentException if the socket was not created by this factory. 341 * @hide 342 */ 343 public byte[] getAlpnSelectedProtocol(Socket socket) { 344 return castToOpenSSLSocket(socket).getAlpnSelectedProtocol(); 345 } 346 347 /** 348 * Sets the {@link KeyManager}s to be used for connections made by this factory. 349 */ 350 public void setKeyManagers(KeyManager[] keyManagers) { 351 mKeyManagers = keyManagers; 352 353 // Clear out any existing cached factories since configurations have changed. 354 mSecureFactory = null; 355 mInsecureFactory = null; 356 } 357 358 /** 359 * Sets the private key to be used for TLS Channel ID by connections made by this 360 * factory. 361 * 362 * @param privateKey private key (enables TLS Channel ID) or {@code null} for no key (disables 363 * TLS Channel ID). The private key has to be an Elliptic Curve (EC) key based on the 364 * NIST P-256 curve (aka SECG secp256r1 or ANSI X9.62 prime256v1). 365 * 366 * @hide 367 */ 368 public void setChannelIdPrivateKey(PrivateKey privateKey) { 369 mChannelIdPrivateKey = privateKey; 370 } 371 372 /** 373 * Enables <a href="http://tools.ietf.org/html/rfc5077#section-3.2">session ticket</a> 374 * support on the given socket. 375 * 376 * @param socket a socket created by this factory 377 * @param useSessionTickets {@code true} to enable session ticket support on this socket. 378 * @throws IllegalArgumentException if the socket was not created by this factory. 379 */ 380 public void setUseSessionTickets(Socket socket, boolean useSessionTickets) { 381 castToOpenSSLSocket(socket).setUseSessionTickets(useSessionTickets); 382 } 383 384 /** 385 * Turns on <a href="http://tools.ietf.org/html/rfc6066#section-3">Server 386 * Name Indication (SNI)</a> on a given socket. 387 * 388 * @param socket a socket created by this factory. 389 * @param hostName the desired SNI hostname, null to disable. 390 * @throws IllegalArgumentException if the socket was not created by this factory. 391 */ 392 public void setHostname(Socket socket, String hostName) { 393 castToOpenSSLSocket(socket).setHostname(hostName); 394 } 395 396 /** 397 * Sets this socket's SO_SNDTIMEO write timeout in milliseconds. 398 * Use 0 for no timeout. 399 * To take effect, this option must be set before the blocking method was called. 400 * 401 * @param socket a socket created by this factory. 402 * @param timeout the desired write timeout in milliseconds. 403 * @throws IllegalArgumentException if the socket was not created by this factory. 404 * 405 * @hide 406 */ 407 public void setSoWriteTimeout(Socket socket, int writeTimeoutMilliseconds) 408 throws SocketException { 409 castToOpenSSLSocket(socket).setSoWriteTimeout(writeTimeoutMilliseconds); 410 } 411 412 private static OpenSSLSocketImpl castToOpenSSLSocket(Socket socket) { 413 if (!(socket instanceof OpenSSLSocketImpl)) { 414 throw new IllegalArgumentException("Socket not created by this factory: " 415 + socket); 416 } 417 418 return (OpenSSLSocketImpl) socket; 419 } 420 421 /** 422 * {@inheritDoc} 423 * 424 * <p>This method verifies the peer's certificate hostname after connecting 425 * (unless created with {@link #getInsecure(int, SSLSessionCache)}). 426 */ 427 @Override 428 public Socket createSocket(Socket k, String host, int port, boolean close) throws IOException { 429 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket(k, host, port, close); 430 s.setNpnProtocols(mNpnProtocols); 431 s.setAlpnProtocols(mAlpnProtocols); 432 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 433 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 434 if (mSecure) { 435 verifyHostname(s, host); 436 } 437 return s; 438 } 439 440 /** 441 * Creates a new socket which is not connected to any remote host. 442 * You must use {@link Socket#connect} to connect the socket. 443 * 444 * <p class="caution"><b>Warning:</b> Hostname verification is not performed 445 * with this method. You MUST verify the server's identity after connecting 446 * the socket to avoid man-in-the-middle attacks.</p> 447 */ 448 @Override 449 public Socket createSocket() throws IOException { 450 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket(); 451 s.setNpnProtocols(mNpnProtocols); 452 s.setAlpnProtocols(mAlpnProtocols); 453 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 454 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 455 return s; 456 } 457 458 /** 459 * {@inheritDoc} 460 * 461 * <p class="caution"><b>Warning:</b> Hostname verification is not performed 462 * with this method. You MUST verify the server's identity after connecting 463 * the socket to avoid man-in-the-middle attacks.</p> 464 */ 465 @Override 466 public Socket createSocket(InetAddress addr, int port, InetAddress localAddr, int localPort) 467 throws IOException { 468 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket( 469 addr, port, localAddr, localPort); 470 s.setNpnProtocols(mNpnProtocols); 471 s.setAlpnProtocols(mAlpnProtocols); 472 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 473 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 474 return s; 475 } 476 477 /** 478 * {@inheritDoc} 479 * 480 * <p class="caution"><b>Warning:</b> Hostname verification is not performed 481 * with this method. You MUST verify the server's identity after connecting 482 * the socket to avoid man-in-the-middle attacks.</p> 483 */ 484 @Override 485 public Socket createSocket(InetAddress addr, int port) throws IOException { 486 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket(addr, port); 487 s.setNpnProtocols(mNpnProtocols); 488 s.setAlpnProtocols(mAlpnProtocols); 489 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 490 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 491 return s; 492 } 493 494 /** 495 * {@inheritDoc} 496 * 497 * <p>This method verifies the peer's certificate hostname after connecting 498 * (unless created with {@link #getInsecure(int, SSLSessionCache)}). 499 */ 500 @Override 501 public Socket createSocket(String host, int port, InetAddress localAddr, int localPort) 502 throws IOException { 503 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket( 504 host, port, localAddr, localPort); 505 s.setNpnProtocols(mNpnProtocols); 506 s.setAlpnProtocols(mAlpnProtocols); 507 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 508 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 509 if (mSecure) { 510 verifyHostname(s, host); 511 } 512 return s; 513 } 514 515 /** 516 * {@inheritDoc} 517 * 518 * <p>This method verifies the peer's certificate hostname after connecting 519 * (unless created with {@link #getInsecure(int, SSLSessionCache)}). 520 */ 521 @Override 522 public Socket createSocket(String host, int port) throws IOException { 523 OpenSSLSocketImpl s = (OpenSSLSocketImpl) getDelegate().createSocket(host, port); 524 s.setNpnProtocols(mNpnProtocols); 525 s.setAlpnProtocols(mAlpnProtocols); 526 s.setHandshakeTimeout(mHandshakeTimeoutMillis); 527 s.setChannelIdPrivateKey(mChannelIdPrivateKey); 528 if (mSecure) { 529 verifyHostname(s, host); 530 } 531 return s; 532 } 533 534 @Override 535 public String[] getDefaultCipherSuites() { 536 return getDelegate().getSupportedCipherSuites(); 537 } 538 539 @Override 540 public String[] getSupportedCipherSuites() { 541 return getDelegate().getSupportedCipherSuites(); 542 } 543 } 544