Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2019 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 static android.net.PlatformVpnProfile.TYPE_IKEV2_IPSEC_PSK; |
| 20 | import static android.net.PlatformVpnProfile.TYPE_IKEV2_IPSEC_RSA; |
| 21 | import static android.net.PlatformVpnProfile.TYPE_IKEV2_IPSEC_USER_PASS; |
| 22 | |
| 23 | import static com.android.internal.annotations.VisibleForTesting.Visibility; |
| 24 | import static com.android.internal.util.Preconditions.checkStringNotEmpty; |
| 25 | |
| 26 | import android.annotation.NonNull; |
| 27 | import android.annotation.Nullable; |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 28 | import android.os.Process; |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 29 | import android.security.Credentials; |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 30 | import android.security.KeyStore; |
| 31 | import android.security.keystore.AndroidKeyStoreProvider; |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 32 | |
| 33 | import com.android.internal.annotations.VisibleForTesting; |
| 34 | import com.android.internal.net.VpnProfile; |
| 35 | |
| 36 | import java.io.IOException; |
| 37 | import java.nio.charset.StandardCharsets; |
| 38 | import java.security.GeneralSecurityException; |
| 39 | import java.security.KeyFactory; |
| 40 | import java.security.NoSuchAlgorithmException; |
| 41 | import java.security.PrivateKey; |
| 42 | import java.security.cert.CertificateEncodingException; |
| 43 | import java.security.cert.CertificateException; |
| 44 | import java.security.cert.X509Certificate; |
| 45 | import java.security.spec.InvalidKeySpecException; |
| 46 | import java.security.spec.PKCS8EncodedKeySpec; |
| 47 | import java.util.ArrayList; |
| 48 | import java.util.Arrays; |
| 49 | import java.util.Base64; |
| 50 | import java.util.Collections; |
| 51 | import java.util.List; |
| 52 | import java.util.Objects; |
| 53 | |
| 54 | /** |
| 55 | * The Ikev2VpnProfile is a configuration for the platform setup of IKEv2/IPsec VPNs. |
| 56 | * |
| 57 | * <p>Together with VpnManager, this allows apps to provision IKEv2/IPsec VPNs that do not require |
| 58 | * the VPN app to constantly run in the background. |
| 59 | * |
| 60 | * @see VpnManager |
| 61 | * @see <a href="https://tools.ietf.org/html/rfc7296#section-3.3.2">RFC 7296 - Internet Key |
| 62 | * Exchange, Version 2 (IKEv2)</a> |
| 63 | */ |
| 64 | public final class Ikev2VpnProfile extends PlatformVpnProfile { |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 65 | /** Prefix for when a Private Key is an alias to look for in KeyStore @hide */ |
| 66 | public static final String PREFIX_KEYSTORE_ALIAS = "KEYSTORE_ALIAS:"; |
| 67 | /** Prefix for when a Private Key is stored directly in the profile @hide */ |
| 68 | public static final String PREFIX_INLINE = "INLINE:"; |
| 69 | |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 70 | private static final String MISSING_PARAM_MSG_TMPL = "Required parameter was not provided: %s"; |
| 71 | private static final String EMPTY_CERT = ""; |
| 72 | |
Benedict Wong | 4fab295 | 2020-04-28 19:26:15 +0000 | [diff] [blame] | 73 | /** @hide */ |
| 74 | public static final List<String> DEFAULT_ALGORITHMS = |
| 75 | Collections.unmodifiableList(Arrays.asList( |
| 76 | IpSecAlgorithm.CRYPT_AES_CBC, |
| 77 | IpSecAlgorithm.AUTH_HMAC_SHA256, |
| 78 | IpSecAlgorithm.AUTH_HMAC_SHA384, |
| 79 | IpSecAlgorithm.AUTH_HMAC_SHA512, |
| 80 | IpSecAlgorithm.AUTH_CRYPT_AES_GCM)); |
| 81 | |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 82 | @NonNull private final String mServerAddr; |
| 83 | @NonNull private final String mUserIdentity; |
| 84 | |
| 85 | // PSK authentication |
| 86 | @Nullable private final byte[] mPresharedKey; |
| 87 | |
| 88 | // Username/Password, RSA authentication |
| 89 | @Nullable private final X509Certificate mServerRootCaCert; |
| 90 | |
| 91 | // Username/Password authentication |
| 92 | @Nullable private final String mUsername; |
| 93 | @Nullable private final String mPassword; |
| 94 | |
| 95 | // RSA Certificate authentication |
| 96 | @Nullable private final PrivateKey mRsaPrivateKey; |
| 97 | @Nullable private final X509Certificate mUserCert; |
| 98 | |
| 99 | @Nullable private final ProxyInfo mProxyInfo; |
| 100 | @NonNull private final List<String> mAllowedAlgorithms; |
| 101 | private final boolean mIsBypassable; // Defaults in builder |
| 102 | private final boolean mIsMetered; // Defaults in builder |
| 103 | private final int mMaxMtu; // Defaults in builder |
| 104 | |
| 105 | private Ikev2VpnProfile( |
| 106 | int type, |
| 107 | @NonNull String serverAddr, |
| 108 | @NonNull String userIdentity, |
| 109 | @Nullable byte[] presharedKey, |
| 110 | @Nullable X509Certificate serverRootCaCert, |
| 111 | @Nullable String username, |
| 112 | @Nullable String password, |
| 113 | @Nullable PrivateKey rsaPrivateKey, |
| 114 | @Nullable X509Certificate userCert, |
| 115 | @Nullable ProxyInfo proxyInfo, |
| 116 | @NonNull List<String> allowedAlgorithms, |
| 117 | boolean isBypassable, |
| 118 | boolean isMetered, |
| 119 | int maxMtu) { |
| 120 | super(type); |
| 121 | |
| 122 | checkNotNull(serverAddr, MISSING_PARAM_MSG_TMPL, "Server address"); |
| 123 | checkNotNull(userIdentity, MISSING_PARAM_MSG_TMPL, "User Identity"); |
| 124 | checkNotNull(allowedAlgorithms, MISSING_PARAM_MSG_TMPL, "Allowed Algorithms"); |
| 125 | |
| 126 | mServerAddr = serverAddr; |
| 127 | mUserIdentity = userIdentity; |
| 128 | mPresharedKey = |
| 129 | presharedKey == null ? null : Arrays.copyOf(presharedKey, presharedKey.length); |
| 130 | mServerRootCaCert = serverRootCaCert; |
| 131 | mUsername = username; |
| 132 | mPassword = password; |
| 133 | mRsaPrivateKey = rsaPrivateKey; |
| 134 | mUserCert = userCert; |
| 135 | mProxyInfo = new ProxyInfo(proxyInfo); |
| 136 | |
| 137 | // UnmodifiableList doesn't make a defensive copy by default. |
| 138 | mAllowedAlgorithms = Collections.unmodifiableList(new ArrayList<>(allowedAlgorithms)); |
| 139 | |
| 140 | mIsBypassable = isBypassable; |
| 141 | mIsMetered = isMetered; |
| 142 | mMaxMtu = maxMtu; |
| 143 | |
| 144 | validate(); |
| 145 | } |
| 146 | |
| 147 | private void validate() { |
| 148 | // Server Address not validated except to check an address was provided. This allows for |
| 149 | // dual-stack servers and hostname based addresses. |
| 150 | checkStringNotEmpty(mServerAddr, MISSING_PARAM_MSG_TMPL, "Server Address"); |
| 151 | checkStringNotEmpty(mUserIdentity, MISSING_PARAM_MSG_TMPL, "User Identity"); |
| 152 | |
| 153 | // IPv6 MTU is greater; since profiles may be started by the system on IPv4 and IPv6 |
| 154 | // networks, the VPN must provide a link fulfilling the stricter of the two conditions |
| 155 | // (at least that of the IPv6 MTU). |
| 156 | if (mMaxMtu < LinkProperties.MIN_MTU_V6) { |
| 157 | throw new IllegalArgumentException( |
| 158 | "Max MTU must be at least" + LinkProperties.MIN_MTU_V6); |
| 159 | } |
| 160 | |
| 161 | switch (mType) { |
| 162 | case TYPE_IKEV2_IPSEC_USER_PASS: |
| 163 | checkNotNull(mUsername, MISSING_PARAM_MSG_TMPL, "Username"); |
| 164 | checkNotNull(mPassword, MISSING_PARAM_MSG_TMPL, "Password"); |
| 165 | |
| 166 | if (mServerRootCaCert != null) checkCert(mServerRootCaCert); |
| 167 | |
| 168 | break; |
| 169 | case TYPE_IKEV2_IPSEC_PSK: |
| 170 | checkNotNull(mPresharedKey, MISSING_PARAM_MSG_TMPL, "Preshared Key"); |
| 171 | break; |
| 172 | case TYPE_IKEV2_IPSEC_RSA: |
| 173 | checkNotNull(mUserCert, MISSING_PARAM_MSG_TMPL, "User cert"); |
| 174 | checkNotNull(mRsaPrivateKey, MISSING_PARAM_MSG_TMPL, "RSA Private key"); |
| 175 | |
| 176 | checkCert(mUserCert); |
| 177 | if (mServerRootCaCert != null) checkCert(mServerRootCaCert); |
| 178 | |
| 179 | break; |
| 180 | default: |
| 181 | throw new IllegalArgumentException("Invalid auth method set"); |
| 182 | } |
| 183 | |
Benedict Wong | 4fab295 | 2020-04-28 19:26:15 +0000 | [diff] [blame] | 184 | validateAllowedAlgorithms(mAllowedAlgorithms); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * Validates that the allowed algorithms are a valid set for IPsec purposes |
| 189 | * |
| 190 | * <p>In order for the algorithm list to be a valid set, it must contain at least one algorithm |
| 191 | * that provides Authentication, and one that provides Encryption. Authenticated Encryption with |
| 192 | * Associated Data (AEAD) algorithms are counted as providing Authentication and Encryption. |
| 193 | * |
| 194 | * @param allowedAlgorithms The list to be validated |
| 195 | */ |
| 196 | private static void validateAllowedAlgorithms(@NonNull List<String> algorithmNames) { |
| 197 | VpnProfile.validateAllowedAlgorithms(algorithmNames); |
| 198 | |
| 199 | // First, make sure no insecure algorithms were proposed. |
| 200 | if (algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_MD5) |
| 201 | || algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_SHA1)) { |
| 202 | throw new IllegalArgumentException("Algorithm not supported for IKEv2 VPN profiles"); |
| 203 | } |
| 204 | |
| 205 | // Validate that some valid combination (AEAD or AUTH + CRYPT) is present |
| 206 | if (hasAeadAlgorithms(algorithmNames) || hasNormalModeAlgorithms(algorithmNames)) { |
| 207 | return; |
| 208 | } |
| 209 | |
| 210 | throw new IllegalArgumentException("Algorithm set missing support for Auth, Crypt or both"); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Checks if the provided list has AEAD algorithms |
| 215 | * |
| 216 | * @hide |
| 217 | */ |
| 218 | public static boolean hasAeadAlgorithms(@NonNull List<String> algorithmNames) { |
| 219 | return algorithmNames.contains(IpSecAlgorithm.AUTH_CRYPT_AES_GCM); |
| 220 | } |
| 221 | |
| 222 | /** |
| 223 | * Checks the provided list has acceptable (non-AEAD) authentication and encryption algorithms |
| 224 | * |
| 225 | * @hide |
| 226 | */ |
| 227 | public static boolean hasNormalModeAlgorithms(@NonNull List<String> algorithmNames) { |
| 228 | final boolean hasCrypt = algorithmNames.contains(IpSecAlgorithm.CRYPT_AES_CBC); |
| 229 | final boolean hasAuth = algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_SHA256) |
| 230 | || algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_SHA384) |
| 231 | || algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_SHA512); |
| 232 | |
| 233 | return hasCrypt && hasAuth; |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 234 | } |
| 235 | |
| 236 | /** Retrieves the server address string. */ |
| 237 | @NonNull |
| 238 | public String getServerAddr() { |
| 239 | return mServerAddr; |
| 240 | } |
| 241 | |
| 242 | /** Retrieves the user identity. */ |
| 243 | @NonNull |
| 244 | public String getUserIdentity() { |
| 245 | return mUserIdentity; |
| 246 | } |
| 247 | |
| 248 | /** |
| 249 | * Retrieves the pre-shared key. |
| 250 | * |
| 251 | * <p>May be null if the profile is not using Pre-shared key authentication. |
| 252 | */ |
| 253 | @Nullable |
| 254 | public byte[] getPresharedKey() { |
| 255 | return mPresharedKey == null ? null : Arrays.copyOf(mPresharedKey, mPresharedKey.length); |
| 256 | } |
| 257 | |
| 258 | /** |
| 259 | * Retrieves the certificate for the server's root CA. |
| 260 | * |
| 261 | * <p>May be null if the profile is not using RSA Digital Signature Authentication or |
| 262 | * Username/Password authentication |
| 263 | */ |
| 264 | @Nullable |
| 265 | public X509Certificate getServerRootCaCert() { |
| 266 | return mServerRootCaCert; |
| 267 | } |
| 268 | |
| 269 | /** |
| 270 | * Retrieves the username. |
| 271 | * |
| 272 | * <p>May be null if the profile is not using Username/Password authentication |
| 273 | */ |
| 274 | @Nullable |
| 275 | public String getUsername() { |
| 276 | return mUsername; |
| 277 | } |
| 278 | |
| 279 | /** |
| 280 | * Retrieves the password. |
| 281 | * |
| 282 | * <p>May be null if the profile is not using Username/Password authentication |
| 283 | */ |
| 284 | @Nullable |
| 285 | public String getPassword() { |
| 286 | return mPassword; |
| 287 | } |
| 288 | |
| 289 | /** |
| 290 | * Retrieves the RSA private key. |
| 291 | * |
| 292 | * <p>May be null if the profile is not using RSA Digital Signature authentication |
| 293 | */ |
| 294 | @Nullable |
| 295 | public PrivateKey getRsaPrivateKey() { |
| 296 | return mRsaPrivateKey; |
| 297 | } |
| 298 | |
| 299 | /** Retrieves the user certificate, if any was set. */ |
| 300 | @Nullable |
| 301 | public X509Certificate getUserCert() { |
| 302 | return mUserCert; |
| 303 | } |
| 304 | |
| 305 | /** Retrieves the proxy information if any was set */ |
| 306 | @Nullable |
| 307 | public ProxyInfo getProxyInfo() { |
| 308 | return mProxyInfo; |
| 309 | } |
| 310 | |
| 311 | /** Returns all the algorithms allowed by this VPN profile. */ |
| 312 | @NonNull |
| 313 | public List<String> getAllowedAlgorithms() { |
| 314 | return mAllowedAlgorithms; |
| 315 | } |
| 316 | |
| 317 | /** Returns whether or not the VPN profile should be bypassable. */ |
| 318 | public boolean isBypassable() { |
| 319 | return mIsBypassable; |
| 320 | } |
| 321 | |
| 322 | /** Returns whether or not the VPN profile should be always considered metered. */ |
| 323 | public boolean isMetered() { |
| 324 | return mIsMetered; |
| 325 | } |
| 326 | |
| 327 | /** Retrieves the maximum MTU set for this VPN profile. */ |
| 328 | public int getMaxMtu() { |
| 329 | return mMaxMtu; |
| 330 | } |
| 331 | |
| 332 | @Override |
| 333 | public int hashCode() { |
| 334 | return Objects.hash( |
| 335 | mType, |
| 336 | mServerAddr, |
| 337 | mUserIdentity, |
| 338 | Arrays.hashCode(mPresharedKey), |
| 339 | mServerRootCaCert, |
| 340 | mUsername, |
| 341 | mPassword, |
| 342 | mRsaPrivateKey, |
| 343 | mUserCert, |
| 344 | mProxyInfo, |
| 345 | mAllowedAlgorithms, |
| 346 | mIsBypassable, |
| 347 | mIsMetered, |
| 348 | mMaxMtu); |
| 349 | } |
| 350 | |
| 351 | @Override |
| 352 | public boolean equals(Object obj) { |
| 353 | if (!(obj instanceof Ikev2VpnProfile)) { |
| 354 | return false; |
| 355 | } |
| 356 | |
| 357 | final Ikev2VpnProfile other = (Ikev2VpnProfile) obj; |
| 358 | return mType == other.mType |
| 359 | && Objects.equals(mServerAddr, other.mServerAddr) |
| 360 | && Objects.equals(mUserIdentity, other.mUserIdentity) |
| 361 | && Arrays.equals(mPresharedKey, other.mPresharedKey) |
| 362 | && Objects.equals(mServerRootCaCert, other.mServerRootCaCert) |
| 363 | && Objects.equals(mUsername, other.mUsername) |
| 364 | && Objects.equals(mPassword, other.mPassword) |
| 365 | && Objects.equals(mRsaPrivateKey, other.mRsaPrivateKey) |
| 366 | && Objects.equals(mUserCert, other.mUserCert) |
| 367 | && Objects.equals(mProxyInfo, other.mProxyInfo) |
| 368 | && Objects.equals(mAllowedAlgorithms, other.mAllowedAlgorithms) |
| 369 | && mIsBypassable == other.mIsBypassable |
| 370 | && mIsMetered == other.mIsMetered |
| 371 | && mMaxMtu == other.mMaxMtu; |
| 372 | } |
| 373 | |
| 374 | /** |
| 375 | * Builds a VpnProfile instance for internal use, based on the stored IKEv2/IPsec parameters. |
| 376 | * |
| 377 | * <p>Redundant authentication information (from previous calls to other setAuth* methods) will |
| 378 | * be discarded. |
| 379 | * |
| 380 | * @hide |
| 381 | */ |
| 382 | @NonNull |
| 383 | public VpnProfile toVpnProfile() throws IOException, GeneralSecurityException { |
| 384 | final VpnProfile profile = new VpnProfile("" /* Key; value unused by IKEv2VpnProfile(s) */); |
| 385 | profile.type = mType; |
| 386 | profile.server = mServerAddr; |
| 387 | profile.ipsecIdentifier = mUserIdentity; |
| 388 | profile.proxy = mProxyInfo; |
| 389 | profile.setAllowedAlgorithms(mAllowedAlgorithms); |
| 390 | profile.isBypassable = mIsBypassable; |
| 391 | profile.isMetered = mIsMetered; |
| 392 | profile.maxMtu = mMaxMtu; |
| 393 | profile.areAuthParamsInline = true; |
| 394 | profile.saveLogin = true; |
| 395 | |
| 396 | switch (mType) { |
| 397 | case TYPE_IKEV2_IPSEC_USER_PASS: |
| 398 | profile.username = mUsername; |
| 399 | profile.password = mPassword; |
| 400 | profile.ipsecCaCert = |
| 401 | mServerRootCaCert == null ? "" : certificateToPemString(mServerRootCaCert); |
| 402 | break; |
| 403 | case TYPE_IKEV2_IPSEC_PSK: |
| 404 | profile.ipsecSecret = encodeForIpsecSecret(mPresharedKey); |
| 405 | break; |
| 406 | case TYPE_IKEV2_IPSEC_RSA: |
| 407 | profile.ipsecUserCert = certificateToPemString(mUserCert); |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 408 | profile.ipsecSecret = |
| 409 | PREFIX_INLINE + encodeForIpsecSecret(mRsaPrivateKey.getEncoded()); |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 410 | profile.ipsecCaCert = |
| 411 | mServerRootCaCert == null ? "" : certificateToPemString(mServerRootCaCert); |
| 412 | break; |
| 413 | default: |
| 414 | throw new IllegalArgumentException("Invalid auth method set"); |
| 415 | } |
| 416 | |
| 417 | return profile; |
| 418 | } |
| 419 | |
| 420 | /** |
| 421 | * Constructs a Ikev2VpnProfile from an internal-use VpnProfile instance. |
| 422 | * |
| 423 | * <p>Redundant authentication information (not related to profile type) will be discarded. |
| 424 | * |
| 425 | * @hide |
| 426 | */ |
| 427 | @NonNull |
| 428 | public static Ikev2VpnProfile fromVpnProfile(@NonNull VpnProfile profile) |
| 429 | throws IOException, GeneralSecurityException { |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 430 | return fromVpnProfile(profile, null); |
| 431 | } |
| 432 | |
| 433 | /** |
| 434 | * Builds the Ikev2VpnProfile from the given profile. |
| 435 | * |
| 436 | * @param profile the source VpnProfile to build from |
| 437 | * @param keyStore the Android Keystore instance to use to retrieve the private key, or null if |
| 438 | * the private key is PEM-encoded into the profile. |
| 439 | * @return The IKEv2/IPsec VPN profile |
| 440 | * @hide |
| 441 | */ |
| 442 | @NonNull |
| 443 | public static Ikev2VpnProfile fromVpnProfile( |
| 444 | @NonNull VpnProfile profile, @Nullable KeyStore keyStore) |
| 445 | throws IOException, GeneralSecurityException { |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 446 | final Builder builder = new Builder(profile.server, profile.ipsecIdentifier); |
| 447 | builder.setProxy(profile.proxy); |
| 448 | builder.setAllowedAlgorithms(profile.getAllowedAlgorithms()); |
| 449 | builder.setBypassable(profile.isBypassable); |
| 450 | builder.setMetered(profile.isMetered); |
| 451 | builder.setMaxMtu(profile.maxMtu); |
| 452 | |
| 453 | switch (profile.type) { |
| 454 | case TYPE_IKEV2_IPSEC_USER_PASS: |
| 455 | builder.setAuthUsernamePassword( |
| 456 | profile.username, |
| 457 | profile.password, |
| 458 | certificateFromPemString(profile.ipsecCaCert)); |
| 459 | break; |
| 460 | case TYPE_IKEV2_IPSEC_PSK: |
| 461 | builder.setAuthPsk(decodeFromIpsecSecret(profile.ipsecSecret)); |
| 462 | break; |
| 463 | case TYPE_IKEV2_IPSEC_RSA: |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 464 | final PrivateKey key; |
| 465 | if (profile.ipsecSecret.startsWith(PREFIX_KEYSTORE_ALIAS)) { |
| 466 | Objects.requireNonNull(keyStore, "Missing Keystore for aliased PrivateKey"); |
| 467 | |
| 468 | final String alias = |
| 469 | profile.ipsecSecret.substring(PREFIX_KEYSTORE_ALIAS.length()); |
| 470 | key = AndroidKeyStoreProvider.loadAndroidKeyStorePrivateKeyFromKeystore( |
| 471 | keyStore, alias, Process.myUid()); |
| 472 | } else if (profile.ipsecSecret.startsWith(PREFIX_INLINE)) { |
| 473 | key = getPrivateKey(profile.ipsecSecret.substring(PREFIX_INLINE.length())); |
| 474 | } else { |
| 475 | throw new IllegalArgumentException("Invalid RSA private key prefix"); |
| 476 | } |
| 477 | |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 478 | final X509Certificate userCert = certificateFromPemString(profile.ipsecUserCert); |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 479 | final X509Certificate serverRootCa = certificateFromPemString(profile.ipsecCaCert); |
| 480 | builder.setAuthDigitalSignature(userCert, key, serverRootCa); |
| 481 | break; |
| 482 | default: |
| 483 | throw new IllegalArgumentException("Invalid auth method set"); |
| 484 | } |
| 485 | |
| 486 | return builder.build(); |
| 487 | } |
| 488 | |
| 489 | /** |
Benedict Wong | 24a2be8 | 2020-01-17 19:41:38 -0800 | [diff] [blame] | 490 | * Validates that the VpnProfile is acceptable for the purposes of an Ikev2VpnProfile. |
| 491 | * |
| 492 | * @hide |
| 493 | */ |
| 494 | public static boolean isValidVpnProfile(@NonNull VpnProfile profile) { |
| 495 | if (profile.server.isEmpty() || profile.ipsecIdentifier.isEmpty()) { |
| 496 | return false; |
| 497 | } |
| 498 | |
| 499 | switch (profile.type) { |
| 500 | case TYPE_IKEV2_IPSEC_USER_PASS: |
| 501 | if (profile.username.isEmpty() || profile.password.isEmpty()) { |
| 502 | return false; |
| 503 | } |
| 504 | break; |
| 505 | case TYPE_IKEV2_IPSEC_PSK: |
| 506 | if (profile.ipsecSecret.isEmpty()) { |
| 507 | return false; |
| 508 | } |
| 509 | break; |
| 510 | case TYPE_IKEV2_IPSEC_RSA: |
| 511 | if (profile.ipsecSecret.isEmpty() || profile.ipsecUserCert.isEmpty()) { |
| 512 | return false; |
| 513 | } |
| 514 | break; |
| 515 | default: |
| 516 | return false; |
| 517 | } |
| 518 | |
| 519 | return true; |
| 520 | } |
| 521 | |
| 522 | /** |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 523 | * Converts a X509 Certificate to a PEM-formatted string. |
| 524 | * |
| 525 | * <p>Must be public due to runtime-package restrictions. |
| 526 | * |
| 527 | * @hide |
| 528 | */ |
| 529 | @NonNull |
| 530 | @VisibleForTesting(visibility = Visibility.PRIVATE) |
| 531 | public static String certificateToPemString(@Nullable X509Certificate cert) |
| 532 | throws IOException, CertificateEncodingException { |
| 533 | if (cert == null) { |
| 534 | return EMPTY_CERT; |
| 535 | } |
| 536 | |
| 537 | // Credentials.convertToPem outputs ASCII bytes. |
| 538 | return new String(Credentials.convertToPem(cert), StandardCharsets.US_ASCII); |
| 539 | } |
| 540 | |
| 541 | /** |
| 542 | * Decodes the provided Certificate(s). |
| 543 | * |
| 544 | * <p>Will use the first one if the certStr encodes more than one certificate. |
| 545 | */ |
| 546 | @Nullable |
| 547 | private static X509Certificate certificateFromPemString(@Nullable String certStr) |
| 548 | throws CertificateException { |
| 549 | if (certStr == null || EMPTY_CERT.equals(certStr)) { |
| 550 | return null; |
| 551 | } |
| 552 | |
| 553 | try { |
| 554 | final List<X509Certificate> certs = |
| 555 | Credentials.convertFromPem(certStr.getBytes(StandardCharsets.US_ASCII)); |
| 556 | return certs.isEmpty() ? null : certs.get(0); |
| 557 | } catch (IOException e) { |
| 558 | throw new CertificateException(e); |
| 559 | } |
| 560 | } |
| 561 | |
| 562 | /** @hide */ |
| 563 | @NonNull |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 564 | public static String encodeForIpsecSecret(@NonNull byte[] secret) { |
| 565 | checkNotNull(secret, MISSING_PARAM_MSG_TMPL, "secret"); |
| 566 | |
| 567 | return Base64.getEncoder().encodeToString(secret); |
| 568 | } |
| 569 | |
| 570 | @NonNull |
| 571 | private static byte[] decodeFromIpsecSecret(@NonNull String encoded) { |
| 572 | checkNotNull(encoded, MISSING_PARAM_MSG_TMPL, "encoded"); |
| 573 | |
| 574 | return Base64.getDecoder().decode(encoded); |
| 575 | } |
| 576 | |
| 577 | @NonNull |
| 578 | private static PrivateKey getPrivateKey(@NonNull String keyStr) |
| 579 | throws InvalidKeySpecException, NoSuchAlgorithmException { |
| 580 | final PKCS8EncodedKeySpec privateKeySpec = |
| 581 | new PKCS8EncodedKeySpec(decodeFromIpsecSecret(keyStr)); |
| 582 | final KeyFactory keyFactory = KeyFactory.getInstance("RSA"); |
| 583 | return keyFactory.generatePrivate(privateKeySpec); |
| 584 | } |
| 585 | |
| 586 | private static void checkCert(@NonNull X509Certificate cert) { |
| 587 | try { |
| 588 | certificateToPemString(cert); |
| 589 | } catch (GeneralSecurityException | IOException e) { |
| 590 | throw new IllegalArgumentException("Certificate could not be encoded"); |
| 591 | } |
| 592 | } |
| 593 | |
| 594 | private static @NonNull <T> T checkNotNull( |
| 595 | final T reference, final String messageTemplate, final Object... messageArgs) { |
| 596 | return Objects.requireNonNull(reference, String.format(messageTemplate, messageArgs)); |
| 597 | } |
| 598 | |
| 599 | /** A incremental builder for IKEv2 VPN profiles */ |
| 600 | public static final class Builder { |
| 601 | private int mType = -1; |
| 602 | @NonNull private final String mServerAddr; |
| 603 | @NonNull private final String mUserIdentity; |
| 604 | |
| 605 | // PSK authentication |
| 606 | @Nullable private byte[] mPresharedKey; |
| 607 | |
| 608 | // Username/Password, RSA authentication |
| 609 | @Nullable private X509Certificate mServerRootCaCert; |
| 610 | |
| 611 | // Username/Password authentication |
| 612 | @Nullable private String mUsername; |
| 613 | @Nullable private String mPassword; |
| 614 | |
| 615 | // RSA Certificate authentication |
| 616 | @Nullable private PrivateKey mRsaPrivateKey; |
| 617 | @Nullable private X509Certificate mUserCert; |
| 618 | |
| 619 | @Nullable private ProxyInfo mProxyInfo; |
Benedict Wong | 4fab295 | 2020-04-28 19:26:15 +0000 | [diff] [blame] | 620 | @NonNull private List<String> mAllowedAlgorithms = DEFAULT_ALGORITHMS; |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 621 | private boolean mIsBypassable = false; |
| 622 | private boolean mIsMetered = true; |
Benedict Wong | 399c136 | 2020-03-26 21:21:03 -0700 | [diff] [blame] | 623 | private int mMaxMtu = PlatformVpnProfile.MAX_MTU_DEFAULT; |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 624 | |
| 625 | /** |
| 626 | * Creates a new builder with the basic parameters of an IKEv2/IPsec VPN. |
| 627 | * |
| 628 | * @param serverAddr the server that the VPN should connect to |
| 629 | * @param identity the identity string to be used for IKEv2 authentication |
| 630 | */ |
| 631 | public Builder(@NonNull String serverAddr, @NonNull String identity) { |
| 632 | checkNotNull(serverAddr, MISSING_PARAM_MSG_TMPL, "serverAddr"); |
| 633 | checkNotNull(identity, MISSING_PARAM_MSG_TMPL, "identity"); |
| 634 | |
| 635 | mServerAddr = serverAddr; |
| 636 | mUserIdentity = identity; |
| 637 | } |
| 638 | |
| 639 | private void resetAuthParams() { |
| 640 | mPresharedKey = null; |
| 641 | mServerRootCaCert = null; |
| 642 | mUsername = null; |
| 643 | mPassword = null; |
| 644 | mRsaPrivateKey = null; |
| 645 | mUserCert = null; |
| 646 | } |
| 647 | |
| 648 | /** |
| 649 | * Set the IKEv2 authentication to use the provided username/password. |
| 650 | * |
| 651 | * <p>Setting this will configure IKEv2 authentication using EAP-MSCHAPv2. Only one |
| 652 | * authentication method may be set. This method will overwrite any previously set |
| 653 | * authentication method. |
| 654 | * |
| 655 | * @param user the username to be used for EAP-MSCHAPv2 authentication |
| 656 | * @param pass the password to be used for EAP-MSCHAPv2 authentication |
| 657 | * @param serverRootCa the root certificate to be used for verifying the identity of the |
| 658 | * server |
| 659 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 660 | * @throws IllegalArgumentException if any of the certificates were invalid or of an |
| 661 | * unrecognized format |
| 662 | */ |
| 663 | @NonNull |
| 664 | public Builder setAuthUsernamePassword( |
| 665 | @NonNull String user, |
| 666 | @NonNull String pass, |
| 667 | @Nullable X509Certificate serverRootCa) { |
| 668 | checkNotNull(user, MISSING_PARAM_MSG_TMPL, "user"); |
| 669 | checkNotNull(pass, MISSING_PARAM_MSG_TMPL, "pass"); |
| 670 | |
| 671 | // Test to make sure all auth params can be encoded safely. |
| 672 | if (serverRootCa != null) checkCert(serverRootCa); |
| 673 | |
| 674 | resetAuthParams(); |
| 675 | mUsername = user; |
| 676 | mPassword = pass; |
| 677 | mServerRootCaCert = serverRootCa; |
| 678 | mType = VpnProfile.TYPE_IKEV2_IPSEC_USER_PASS; |
| 679 | return this; |
| 680 | } |
| 681 | |
| 682 | /** |
| 683 | * Set the IKEv2 authentication to use Digital Signature Authentication with the given key. |
| 684 | * |
| 685 | * <p>Setting this will configure IKEv2 authentication using a Digital Signature scheme. |
| 686 | * Only one authentication method may be set. This method will overwrite any previously set |
| 687 | * authentication method. |
| 688 | * |
| 689 | * @param userCert the username to be used for RSA Digital signiture authentication |
| 690 | * @param key the PrivateKey instance associated with the user ceritificate, used for |
| 691 | * constructing the signature |
| 692 | * @param serverRootCa the root certificate to be used for verifying the identity of the |
| 693 | * server |
| 694 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 695 | * @throws IllegalArgumentException if any of the certificates were invalid or of an |
| 696 | * unrecognized format |
| 697 | */ |
| 698 | @NonNull |
| 699 | public Builder setAuthDigitalSignature( |
| 700 | @NonNull X509Certificate userCert, |
| 701 | @NonNull PrivateKey key, |
| 702 | @Nullable X509Certificate serverRootCa) { |
| 703 | checkNotNull(userCert, MISSING_PARAM_MSG_TMPL, "userCert"); |
| 704 | checkNotNull(key, MISSING_PARAM_MSG_TMPL, "key"); |
| 705 | |
| 706 | // Test to make sure all auth params can be encoded safely. |
| 707 | checkCert(userCert); |
| 708 | if (serverRootCa != null) checkCert(serverRootCa); |
| 709 | |
| 710 | resetAuthParams(); |
| 711 | mUserCert = userCert; |
| 712 | mRsaPrivateKey = key; |
| 713 | mServerRootCaCert = serverRootCa; |
| 714 | mType = VpnProfile.TYPE_IKEV2_IPSEC_RSA; |
| 715 | return this; |
| 716 | } |
| 717 | |
| 718 | /** |
| 719 | * Set the IKEv2 authentication to use Preshared keys. |
| 720 | * |
| 721 | * <p>Setting this will configure IKEv2 authentication using a Preshared Key. Only one |
| 722 | * authentication method may be set. This method will overwrite any previously set |
| 723 | * authentication method. |
| 724 | * |
| 725 | * @param psk the key to be used for Pre-Shared Key authentication |
| 726 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 727 | */ |
| 728 | @NonNull |
| 729 | public Builder setAuthPsk(@NonNull byte[] psk) { |
| 730 | checkNotNull(psk, MISSING_PARAM_MSG_TMPL, "psk"); |
| 731 | |
| 732 | resetAuthParams(); |
| 733 | mPresharedKey = psk; |
| 734 | mType = VpnProfile.TYPE_IKEV2_IPSEC_PSK; |
| 735 | return this; |
| 736 | } |
| 737 | |
| 738 | /** |
| 739 | * Sets whether apps can bypass this VPN connection. |
| 740 | * |
| 741 | * <p>By default, all traffic from apps are forwarded through the VPN interface and it is |
| 742 | * not possible for unprivileged apps to side-step the VPN. If a VPN is set to bypassable, |
| 743 | * apps may use methods such as {@link Network#getSocketFactory} or {@link |
| 744 | * Network#openConnection} to instead send/receive directly over the underlying network or |
| 745 | * any other network they have permissions for. |
| 746 | * |
| 747 | * @param isBypassable Whether or not the VPN should be considered bypassable. Defaults to |
| 748 | * {@code false}. |
| 749 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 750 | */ |
| 751 | @NonNull |
| 752 | public Builder setBypassable(boolean isBypassable) { |
| 753 | mIsBypassable = isBypassable; |
| 754 | return this; |
| 755 | } |
| 756 | |
| 757 | /** |
| 758 | * Sets a proxy for the VPN network. |
| 759 | * |
| 760 | * <p>Note that this proxy is only a recommendation and it may be ignored by apps. |
| 761 | * |
| 762 | * @param proxy the ProxyInfo to be set for the VPN network |
| 763 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 764 | */ |
| 765 | @NonNull |
| 766 | public Builder setProxy(@Nullable ProxyInfo proxy) { |
| 767 | mProxyInfo = proxy; |
| 768 | return this; |
| 769 | } |
| 770 | |
| 771 | /** |
| 772 | * Set the upper bound of the maximum transmission unit (MTU) of the VPN interface. |
| 773 | * |
| 774 | * <p>If it is not set, a safe value will be used. Additionally, the actual link MTU will be |
| 775 | * dynamically calculated/updated based on the underlying link's mtu. |
| 776 | * |
| 777 | * @param mtu the MTU (in bytes) of the VPN interface |
| 778 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 779 | * @throws IllegalArgumentException if the value is not at least the minimum IPv6 MTU (1280) |
| 780 | */ |
| 781 | @NonNull |
| 782 | public Builder setMaxMtu(int mtu) { |
| 783 | // IPv6 MTU is greater; since profiles may be started by the system on IPv4 and IPv6 |
| 784 | // networks, the VPN must provide a link fulfilling the stricter of the two conditions |
| 785 | // (at least that of the IPv6 MTU). |
| 786 | if (mtu < LinkProperties.MIN_MTU_V6) { |
| 787 | throw new IllegalArgumentException( |
| 788 | "Max MTU must be at least " + LinkProperties.MIN_MTU_V6); |
| 789 | } |
| 790 | mMaxMtu = mtu; |
| 791 | return this; |
| 792 | } |
| 793 | |
| 794 | /** |
| 795 | * Marks the VPN network as metered. |
| 796 | * |
| 797 | * <p>A VPN network is classified as metered when the user is sensitive to heavy data usage |
| 798 | * due to monetary costs and/or data limitations. In such cases, you should set this to |
| 799 | * {@code true} so that apps on the system can avoid doing large data transfers. Otherwise, |
| 800 | * set this to {@code false}. Doing so would cause VPN network to inherit its meteredness |
| 801 | * from the underlying network. |
| 802 | * |
| 803 | * @param isMetered {@code true} if the VPN network should be treated as metered regardless |
| 804 | * of underlying network meteredness. Defaults to {@code true}. |
| 805 | * @return this {@link Builder} object to facilitate chaining of method calls |
Andrew Sapperstein | 8fe35e5 | 2020-04-28 12:29:20 -0700 | [diff] [blame] | 806 | * @see NetworkCapabilities#NET_CAPABILITY_NOT_METERED |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 807 | */ |
| 808 | @NonNull |
| 809 | public Builder setMetered(boolean isMetered) { |
| 810 | mIsMetered = isMetered; |
| 811 | return this; |
| 812 | } |
| 813 | |
| 814 | /** |
| 815 | * Sets the allowable set of IPsec algorithms |
| 816 | * |
Benedict Wong | 4fab295 | 2020-04-28 19:26:15 +0000 | [diff] [blame] | 817 | * <p>If set, this will constrain the set of algorithms that the IPsec tunnel will use for |
| 818 | * integrity verification and encryption to the provided list. |
| 819 | * |
| 820 | * <p>The set of allowed IPsec algorithms is defined in {@link IpSecAlgorithm}. Adding of |
| 821 | * algorithms that are considered insecure (such as AUTH_HMAC_MD5 and AUTH_HMAC_SHA1) is not |
| 822 | * permitted, and will result in an IllegalArgumentException being thrown. |
| 823 | * |
| 824 | * <p>The provided algorithm list must contain at least one algorithm that provides |
| 825 | * Authentication, and one that provides Encryption. Authenticated Encryption with |
| 826 | * Associated Data (AEAD) algorithms provide both Authentication and Encryption. |
| 827 | * |
| 828 | * <p>By default, this profile will use any algorithm defined in {@link IpSecAlgorithm}, |
| 829 | * with the exception of those considered insecure (as described above). |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 830 | * |
| 831 | * @param algorithmNames the list of supported IPsec algorithms |
| 832 | * @return this {@link Builder} object to facilitate chaining of method calls |
| 833 | * @see IpSecAlgorithm |
| 834 | */ |
| 835 | @NonNull |
| 836 | public Builder setAllowedAlgorithms(@NonNull List<String> algorithmNames) { |
| 837 | checkNotNull(algorithmNames, MISSING_PARAM_MSG_TMPL, "algorithmNames"); |
Benedict Wong | 4fab295 | 2020-04-28 19:26:15 +0000 | [diff] [blame] | 838 | validateAllowedAlgorithms(algorithmNames); |
Benedict Wong | feb69c1 | 2019-11-01 16:45:08 -0700 | [diff] [blame] | 839 | |
| 840 | mAllowedAlgorithms = algorithmNames; |
| 841 | return this; |
| 842 | } |
| 843 | |
| 844 | /** |
| 845 | * Validates, builds and provisions the VpnProfile. |
| 846 | * |
| 847 | * @throws IllegalArgumentException if any of the required keys or values were invalid |
| 848 | */ |
| 849 | @NonNull |
| 850 | public Ikev2VpnProfile build() { |
| 851 | return new Ikev2VpnProfile( |
| 852 | mType, |
| 853 | mServerAddr, |
| 854 | mUserIdentity, |
| 855 | mPresharedKey, |
| 856 | mServerRootCaCert, |
| 857 | mUsername, |
| 858 | mPassword, |
| 859 | mRsaPrivateKey, |
| 860 | mUserCert, |
| 861 | mProxyInfo, |
| 862 | mAllowedAlgorithms, |
| 863 | mIsBypassable, |
| 864 | mIsMetered, |
| 865 | mMaxMtu); |
| 866 | } |
| 867 | } |
| 868 | } |