From ff4112159711efea1df9b2ab248009fd9baed27a Mon Sep 17 00:00:00 2001 From: Yan Yan Date: Fri, 21 May 2021 23:26:54 +0000 Subject: [PATCH] Improve IKEv2/IPsec VPN by proposing more IPsec algorithms This commit allows IKEv2/IPsec VPN to propose more algorithms that newly added in IpSecAlgorithm. Those new algorithms have stronger security guarantees and better performances. This commit also removes algorithm name validation because all algorithms are URL encoded to ensure no special characters create problems due to their use by VpnProfile for list or field delimiting (e.g. rfc7539esp(chacha20,poly1305)) Bug: 185265778 Test: atest FrameworksNetTests, CtsNetTestCases Test: All new algorithms are manually verified Change-Id: I1de322c95aacc8924e95bcdbcfdbd1ec441de99c Merged-In: I1de322c95aacc8924e95bcdbcfdbd1ec441de99c --- core/java/android/net/Ikev2VpnProfile.java | 41 +++++++++++--- .../com/android/internal/net/VpnProfile.java | 46 ++++++++-------- .../java/android/net/Ikev2VpnProfileTest.java | 14 ++++- .../android/internal/net/VpnProfileTest.java | 26 +-------- .../server/connectivity/VpnIkev2Utils.java | 55 +++++++++++++------ 5 files changed, 107 insertions(+), 75 deletions(-) diff --git a/core/java/android/net/Ikev2VpnProfile.java b/core/java/android/net/Ikev2VpnProfile.java index cc1312bac1807..b18e9be28eb57 100644 --- a/core/java/android/net/Ikev2VpnProfile.java +++ b/core/java/android/net/Ikev2VpnProfile.java @@ -16,6 +16,16 @@ package android.net; +import static android.net.IpSecAlgorithm.AUTH_AES_CMAC; +import static android.net.IpSecAlgorithm.AUTH_AES_XCBC; +import static android.net.IpSecAlgorithm.AUTH_CRYPT_AES_GCM; +import static android.net.IpSecAlgorithm.AUTH_CRYPT_CHACHA20_POLY1305; +import static android.net.IpSecAlgorithm.AUTH_HMAC_SHA256; +import static android.net.IpSecAlgorithm.AUTH_HMAC_SHA384; +import static android.net.IpSecAlgorithm.AUTH_HMAC_SHA512; +import static android.net.IpSecAlgorithm.CRYPT_AES_CBC; +import static android.net.IpSecAlgorithm.CRYPT_AES_CTR; + import static com.android.internal.annotations.VisibleForTesting.Visibility; import static com.android.internal.util.Preconditions.checkStringNotEmpty; import static com.android.net.module.util.NetworkStackConstants.IPV6_MIN_MTU; @@ -70,13 +80,28 @@ public final class Ikev2VpnProfile extends PlatformVpnProfile { private static final String EMPTY_CERT = ""; /** @hide */ - public static final List DEFAULT_ALGORITHMS = - Collections.unmodifiableList(Arrays.asList( - IpSecAlgorithm.CRYPT_AES_CBC, - IpSecAlgorithm.AUTH_HMAC_SHA256, - IpSecAlgorithm.AUTH_HMAC_SHA384, - IpSecAlgorithm.AUTH_HMAC_SHA512, - IpSecAlgorithm.AUTH_CRYPT_AES_GCM)); + public static final List DEFAULT_ALGORITHMS; + + private static void addAlgorithmIfSupported(List algorithms, String ipSecAlgoName) { + if (IpSecAlgorithm.getSupportedAlgorithms().contains(ipSecAlgoName)) { + algorithms.add(ipSecAlgoName); + } + } + + static { + final List algorithms = new ArrayList<>(); + addAlgorithmIfSupported(algorithms, CRYPT_AES_CBC); + addAlgorithmIfSupported(algorithms, CRYPT_AES_CTR); + addAlgorithmIfSupported(algorithms, AUTH_HMAC_SHA256); + addAlgorithmIfSupported(algorithms, AUTH_HMAC_SHA384); + addAlgorithmIfSupported(algorithms, AUTH_HMAC_SHA512); + addAlgorithmIfSupported(algorithms, AUTH_AES_XCBC); + addAlgorithmIfSupported(algorithms, AUTH_AES_CMAC); + addAlgorithmIfSupported(algorithms, AUTH_CRYPT_AES_GCM); + addAlgorithmIfSupported(algorithms, AUTH_CRYPT_CHACHA20_POLY1305); + + DEFAULT_ALGORITHMS = Collections.unmodifiableList(algorithms); + } @NonNull private final String mServerAddr; @NonNull private final String mUserIdentity; @@ -195,8 +220,6 @@ public final class Ikev2VpnProfile extends PlatformVpnProfile { * @param allowedAlgorithms The list to be validated */ private static void validateAllowedAlgorithms(@NonNull List algorithmNames) { - VpnProfile.validateAllowedAlgorithms(algorithmNames); - // First, make sure no insecure algorithms were proposed. if (algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_MD5) || algorithmNames.contains(IpSecAlgorithm.AUTH_HMAC_SHA1)) { diff --git a/core/java/com/android/internal/net/VpnProfile.java b/core/java/com/android/internal/net/VpnProfile.java index b7170d857da94..6e1d3ce9a2979 100644 --- a/core/java/com/android/internal/net/VpnProfile.java +++ b/core/java/com/android/internal/net/VpnProfile.java @@ -30,7 +30,10 @@ import android.text.TextUtils; import com.android.internal.annotations.VisibleForTesting; import com.android.net.module.util.ProxyUtils; +import java.io.UnsupportedEncodingException; import java.net.InetAddress; +import java.net.URLDecoder; +import java.net.URLEncoder; import java.nio.charset.StandardCharsets; import java.util.ArrayList; import java.util.Arrays; @@ -74,6 +77,9 @@ public final class VpnProfile implements Cloneable, Parcelable { private static final String ENCODED_NULL_PROXY_INFO = "\0\0\0\0"; + /** Default URL encoding. */ + private static final String DEFAULT_ENCODING = StandardCharsets.UTF_8.name(); + // Entity fields. @UnsupportedAppUsage public final String key; // -1 @@ -129,9 +135,6 @@ public final class VpnProfile implements Cloneable, Parcelable { /** * The list of allowable algorithms. - * - *

This list is validated in the setter to ensure that encoding characters (list, value - * delimiters) are not present in the algorithm names. See {@link #validateAllowedAlgorithms()} */ private List mAllowedAlgorithms = new ArrayList<>(); // 19 public boolean isBypassable = false; // 20 @@ -196,11 +199,8 @@ public final class VpnProfile implements Cloneable, Parcelable { * * @param allowedAlgorithms the list of allowable algorithms, as listed in {@link * IpSecAlgorithm}. - * @throws IllegalArgumentException if any delimiters are used in algorithm names. See {@link - * #VALUE_DELIMITER} and {@link LIST_DELIMITER}. */ public void setAllowedAlgorithms(List allowedAlgorithms) { - validateAllowedAlgorithms(allowedAlgorithms); mAllowedAlgorithms = allowedAlgorithms; } @@ -297,7 +297,11 @@ public final class VpnProfile implements Cloneable, Parcelable { // Either all must be present, or none must be. if (values.length >= 24) { - profile.mAllowedAlgorithms = Arrays.asList(values[19].split(LIST_DELIMITER)); + profile.mAllowedAlgorithms = new ArrayList<>(); + for (String algo : Arrays.asList(values[19].split(LIST_DELIMITER))) { + profile.mAllowedAlgorithms.add(URLDecoder.decode(algo, DEFAULT_ENCODING)); + } + profile.isBypassable = Boolean.parseBoolean(values[20]); profile.isMetered = Boolean.parseBoolean(values[21]); profile.maxMtu = Integer.parseInt(values[22]); @@ -348,7 +352,19 @@ public final class VpnProfile implements Cloneable, Parcelable { builder.append(ENCODED_NULL_PROXY_INFO); } - builder.append(VALUE_DELIMITER).append(String.join(LIST_DELIMITER, mAllowedAlgorithms)); + final List encodedAlgoNames = new ArrayList<>(); + + try { + for (String algo : mAllowedAlgorithms) { + encodedAlgoNames.add(URLEncoder.encode(algo, DEFAULT_ENCODING)); + } + } catch (UnsupportedEncodingException e) { + // Unexpected error + throw new IllegalStateException("Failed to encode algorithms.", e); + } + + builder.append(VALUE_DELIMITER).append(String.join(LIST_DELIMITER, encodedAlgoNames)); + builder.append(VALUE_DELIMITER).append(isBypassable); builder.append(VALUE_DELIMITER).append(isMetered); builder.append(VALUE_DELIMITER).append(maxMtu); @@ -425,20 +441,6 @@ public final class VpnProfile implements Cloneable, Parcelable { return true; } - /** - * Validates that the provided list of algorithms does not contain illegal characters. - * - * @param allowedAlgorithms The list to be validated - */ - public static void validateAllowedAlgorithms(List allowedAlgorithms) { - for (final String alg : allowedAlgorithms) { - if (alg.contains(VALUE_DELIMITER) || alg.contains(LIST_DELIMITER)) { - throw new IllegalArgumentException( - "Algorithm contained illegal ('\0' or ',') character"); - } - } - } - /** Generates a hashcode over the VpnProfile. */ @Override public int hashCode() { diff --git a/packages/Connectivity/tests/unit/java/android/net/Ikev2VpnProfileTest.java b/packages/Connectivity/tests/unit/java/android/net/Ikev2VpnProfileTest.java index 1abd39a32bdfc..0707ef3ed1d63 100644 --- a/packages/Connectivity/tests/unit/java/android/net/Ikev2VpnProfileTest.java +++ b/packages/Connectivity/tests/unit/java/android/net/Ikev2VpnProfileTest.java @@ -29,8 +29,8 @@ import androidx.test.filters.SmallTest; import androidx.test.runner.AndroidJUnit4; import com.android.internal.net.VpnProfile; -import com.android.net.module.util.ProxyUtils; import com.android.internal.org.bouncycastle.x509.X509V1CertificateGenerator; +import com.android.net.module.util.ProxyUtils; import org.junit.Before; import org.junit.Test; @@ -170,7 +170,10 @@ public class Ikev2VpnProfileTest { final Ikev2VpnProfile.Builder builder = getBuilderWithDefaultOptions(); builder.setAuthPsk(PSK_BYTES); - List allowedAlgorithms = Arrays.asList(IpSecAlgorithm.AUTH_CRYPT_AES_GCM); + List allowedAlgorithms = + Arrays.asList( + IpSecAlgorithm.AUTH_CRYPT_AES_GCM, + IpSecAlgorithm.AUTH_CRYPT_CHACHA20_POLY1305); builder.setAllowedAlgorithms(allowedAlgorithms); final Ikev2VpnProfile profile = builder.build(); @@ -183,7 +186,12 @@ public class Ikev2VpnProfileTest { builder.setAuthPsk(PSK_BYTES); List allowedAlgorithms = - Arrays.asList(IpSecAlgorithm.AUTH_HMAC_SHA512, IpSecAlgorithm.CRYPT_AES_CBC); + Arrays.asList( + IpSecAlgorithm.AUTH_HMAC_SHA512, + IpSecAlgorithm.AUTH_AES_XCBC, + IpSecAlgorithm.AUTH_AES_CMAC, + IpSecAlgorithm.CRYPT_AES_CBC, + IpSecAlgorithm.CRYPT_AES_CTR); builder.setAllowedAlgorithms(allowedAlgorithms); final Ikev2VpnProfile profile = builder.build(); diff --git a/packages/Connectivity/tests/unit/java/com/android/internal/net/VpnProfileTest.java b/packages/Connectivity/tests/unit/java/com/android/internal/net/VpnProfileTest.java index 46597d19ef1b4..cb0f0710d6e7f 100644 --- a/packages/Connectivity/tests/unit/java/com/android/internal/net/VpnProfileTest.java +++ b/packages/Connectivity/tests/unit/java/com/android/internal/net/VpnProfileTest.java @@ -23,7 +23,6 @@ import static org.junit.Assert.assertFalse; import static org.junit.Assert.assertNotEquals; import static org.junit.Assert.assertNull; import static org.junit.Assert.assertTrue; -import static org.junit.Assert.fail; import android.net.IpSecAlgorithm; @@ -97,6 +96,7 @@ public class VpnProfileTest { p.setAllowedAlgorithms( Arrays.asList( IpSecAlgorithm.AUTH_CRYPT_AES_GCM, + IpSecAlgorithm.AUTH_CRYPT_CHACHA20_POLY1305, IpSecAlgorithm.AUTH_HMAC_SHA512, IpSecAlgorithm.CRYPT_AES_CBC)); p.isBypassable = true; @@ -125,30 +125,6 @@ public class VpnProfileTest { assertParcelSane(getSampleIkev2Profile(DUMMY_PROFILE_KEY), 23); } - @Test - public void testSetInvalidAlgorithmValueDelimiter() { - final VpnProfile profile = getSampleIkev2Profile(DUMMY_PROFILE_KEY); - - try { - profile.setAllowedAlgorithms( - Arrays.asList("test" + VpnProfile.VALUE_DELIMITER + "test")); - fail("Expected failure due to value separator in algorithm name"); - } catch (IllegalArgumentException expected) { - } - } - - @Test - public void testSetInvalidAlgorithmListDelimiter() { - final VpnProfile profile = getSampleIkev2Profile(DUMMY_PROFILE_KEY); - - try { - profile.setAllowedAlgorithms( - Arrays.asList("test" + VpnProfile.LIST_DELIMITER + "test")); - fail("Expected failure due to value separator in algorithm name"); - } catch (IllegalArgumentException expected) { - } - } - @Test public void testEncodeDecode() { final VpnProfile profile = getSampleIkev2Profile(DUMMY_PROFILE_KEY); diff --git a/services/core/java/com/android/server/connectivity/VpnIkev2Utils.java b/services/core/java/com/android/server/connectivity/VpnIkev2Utils.java index 887665cfff2a3..a0a596d998bf9 100644 --- a/services/core/java/com/android/server/connectivity/VpnIkev2Utils.java +++ b/services/core/java/com/android/server/connectivity/VpnIkev2Utils.java @@ -213,19 +213,25 @@ public class VpnIkev2Utils { /** Builds a child SA proposal based on the allowed IPsec algorithms */ private static List getChildSaProposals(List allowedAlgorithms) { - // TODO: Add new IpSecAlgorithm in the followup commit - final List proposals = new ArrayList<>(); + final List aesKeyLenOptions = + Arrays.asList(KEY_LEN_AES_256, KEY_LEN_AES_192, KEY_LEN_AES_128); + // Add non-AEAD options if (Ikev2VpnProfile.hasNormalModeAlgorithms(allowedAlgorithms)) { final ChildSaProposal.Builder normalModeBuilder = new ChildSaProposal.Builder(); // Encryption Algorithms: - // AES-CBC is currently the only supported encryption algorithm. - normalModeBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_CBC, KEY_LEN_AES_256); - normalModeBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_CBC, KEY_LEN_AES_192); - normalModeBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_CBC, KEY_LEN_AES_128); + // AES-CBC and AES_CTR are currently the only supported encryption algorithms. + for (int len : aesKeyLenOptions) { + if (allowedAlgorithms.contains(IpSecAlgorithm.CRYPT_AES_CTR)) { + normalModeBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_CTR, len); + } + if (allowedAlgorithms.contains(IpSecAlgorithm.CRYPT_AES_CBC)) { + normalModeBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_CBC, len); + } + } // Authentication/Integrity Algorithms: // Guaranteed by Ikev2VpnProfile constructor to contain at least one of these. @@ -238,6 +244,12 @@ public class VpnIkev2Utils { if (allowedAlgorithms.contains(IpSecAlgorithm.AUTH_HMAC_SHA256)) { normalModeBuilder.addIntegrityAlgorithm(INTEGRITY_ALGORITHM_HMAC_SHA2_256_128); } + if (allowedAlgorithms.contains(IpSecAlgorithm.AUTH_AES_XCBC)) { + normalModeBuilder.addIntegrityAlgorithm(INTEGRITY_ALGORITHM_AES_XCBC_96); + } + if (allowedAlgorithms.contains(IpSecAlgorithm.AUTH_AES_CMAC)) { + normalModeBuilder.addIntegrityAlgorithm(INTEGRITY_ALGORITHM_AES_CMAC_96); + } ChildSaProposal proposal = normalModeBuilder.build(); if (proposal.getIntegrityAlgorithms().isEmpty()) { @@ -252,16 +264,27 @@ public class VpnIkev2Utils { if (Ikev2VpnProfile.hasAeadAlgorithms(allowedAlgorithms)) { final ChildSaProposal.Builder aeadBuilder = new ChildSaProposal.Builder(); - // AES-GCM is currently the only supported AEAD algorithm - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_256); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_256); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_256); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_192); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_192); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_192); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_128); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_128); - aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_128); + if (allowedAlgorithms.contains(IpSecAlgorithm.AUTH_CRYPT_CHACHA20_POLY1305)) { + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_CHACHA20_POLY1305, KEY_LEN_UNUSED); + } + if (allowedAlgorithms.contains(IpSecAlgorithm.AUTH_CRYPT_AES_GCM)) { + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_256); + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_256); + aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_256); + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_192); + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_192); + aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_192); + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_16, KEY_LEN_AES_128); + aeadBuilder.addEncryptionAlgorithm( + ENCRYPTION_ALGORITHM_AES_GCM_12, KEY_LEN_AES_128); + aeadBuilder.addEncryptionAlgorithm(ENCRYPTION_ALGORITHM_AES_GCM_8, KEY_LEN_AES_128); + } proposals.add(aeadBuilder.build()); }