Limit supported cipher suites

Author: yostyle

changelog.d/4192.misc

@@ -0,0 +1 @@
+Limit supported TLS versions and cipher suites

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/MatrixConfiguration.kt

@@ -16,6 +16,7 @@
 
 package org.matrix.android.sdk.api
 
+import okhttp3.ConnectionSpec
 import org.matrix.android.sdk.api.crypto.MXCryptoConfig
 import java.net.Proxy
 
@@ -44,6 +45,10 @@ data class MatrixConfiguration(
          * You can create one using for instance Proxy(proxyType, InetSocketAddress.createUnresolved(hostname, port).
          */
         val proxy: Proxy? = null,
+        /**
+         * TLS versions and cipher suites limitation for unauthenticated requests
+         */
+        val connectionSpec: ConnectionSpec = ConnectionSpec.RESTRICTED_TLS,
         /**
          * True to advertise support for call transfers to other parties on Matrix calls.
          */

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/auth/data/HomeServerConnectionConfig.kt

@@ -19,6 +19,7 @@ package org.matrix.android.sdk.api.auth.data
 import android.net.Uri
 import com.squareup.moshi.JsonClass
 import okhttp3.CipherSuite
+import okhttp3.ConnectionSpec
 import okhttp3.TlsVersion
 import org.matrix.android.sdk.api.auth.data.HomeServerConnectionConfig.Builder
 import org.matrix.android.sdk.internal.network.ssl.Fingerprint
@@ -191,32 +192,25 @@ data class HomeServerConnectionConfig(
         /**
          * Convenient method to limit the TLS versions and cipher suites for this Builder
          * Ref:
-         * - https://www.ssi.gouv.fr/uploads/2017/02/security-recommendations-for-tls_v1.1.pdf
+         * - https://www.ssi.gouv.fr/uploads/2017/07/anssi-guide-recommandations_de_securite_relatives_a_tls-v1.2.pdf
          * - https://developer.android.com/reference/javax/net/ssl/SSLEngine
          *
          * @param tlsLimitations         true to use Tls limitations
          * @param enableCompatibilityMode set to true for Android < 20
          * @return this builder
          */
+        @Deprecated("TLS versions and cipher suites are limited by default")
         fun withTlsLimitations(tlsLimitations: Boolean, enableCompatibilityMode: Boolean): Builder {
             if (tlsLimitations) {
                 withShouldAcceptTlsExtensions(false)
 
-                // Tls versions
-                addAcceptedTlsVersion(TlsVersion.TLS_1_2)
-                addAcceptedTlsVersion(TlsVersion.TLS_1_3)
+                // TlS versions
+                ConnectionSpec.RESTRICTED_TLS.tlsVersions?.let { this.tlsVersions.addAll(it) }
 
                 forceUsageOfTlsVersions(enableCompatibilityMode)
 
                 // Cipher suites
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256)
-                addAcceptedTlsCipherSuite(CipherSuite.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256)
+                ConnectionSpec.RESTRICTED_TLS.cipherSuites?.let { this.tlsCipherSuites.addAll(it) }
 
                 if (enableCompatibilityMode) {
                     // Adopt some preceding cipher suites for Android < 20 to be able to negotiate

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/di/NetworkModule.kt

@@ -20,6 +20,7 @@ import com.facebook.stetho.okhttp3.StethoInterceptor
 import com.squareup.moshi.Moshi
 import dagger.Module
 import dagger.Provides
+import okhttp3.ConnectionSpec
 import okhttp3.OkHttpClient
 import okhttp3.logging.HttpLoggingInterceptor
 import org.matrix.android.sdk.BuildConfig
@@ -29,6 +30,7 @@ import org.matrix.android.sdk.internal.network.TimeOutInterceptor
 import org.matrix.android.sdk.internal.network.UserAgentInterceptor
 import org.matrix.android.sdk.internal.network.interceptors.CurlLoggingInterceptor
 import org.matrix.android.sdk.internal.network.interceptors.FormattedJsonHttpLogger
+import java.util.Collections
 import java.util.concurrent.TimeUnit
 
 @Module
@@ -66,6 +68,8 @@ internal object NetworkModule {
                              httpLoggingInterceptor: HttpLoggingInterceptor,
                              curlLoggingInterceptor: CurlLoggingInterceptor,
                              apiInterceptor: ApiInterceptor): OkHttpClient {
+        val spec = ConnectionSpec.Builder(matrixConfiguration.connectionSpec).build()
+
         return OkHttpClient.Builder()
                 .connectTimeout(30, TimeUnit.SECONDS)
                 .readTimeout(60, TimeUnit.SECONDS)
@@ -87,6 +91,7 @@ internal object NetworkModule {
                         proxy(it)
                     }
                 }
+                .connectionSpecs(Collections.singletonList(spec))
                 .build()
     }
 

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/network/ssl/CertUtil.kt

@@ -177,15 +177,13 @@ internal object CertUtil {
 
             val trustPinned = arrayOf<TrustManager>(PinnedTrustManagerProvider.provide(hsConfig.allowedFingerprints, defaultTrustManager))
 
-            val sslSocketFactory: SSLSocketFactory
-
-            if (hsConfig.forceUsageTlsVersions && hsConfig.tlsVersions != null) {
+            val sslSocketFactory = if (hsConfig.forceUsageTlsVersions && !hsConfig.tlsVersions.isNullOrEmpty()) {
                 // Force usage of accepted Tls Versions for Android < 20
-                sslSocketFactory = TLSSocketFactory(trustPinned, hsConfig.tlsVersions)
+                TLSSocketFactory(trustPinned, hsConfig.tlsVersions)
             } else {
                 val sslContext = SSLContext.getInstance("TLS")
                 sslContext.init(null, trustPinned, java.security.SecureRandom())
-                sslSocketFactory = sslContext.socketFactory
+                sslContext.socketFactory
             }
 
             return PinnedSSLSocketFactory(sslSocketFactory, defaultTrustManager!!)
@@ -237,14 +235,14 @@ internal object CertUtil {
      * @return a list of accepted TLS specifications.
      */
     fun newConnectionSpecs(hsConfig: HomeServerConnectionConfig): List<ConnectionSpec> {
-        val builder = ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
+        val builder = ConnectionSpec.Builder(ConnectionSpec.RESTRICTED_TLS)
         val tlsVersions = hsConfig.tlsVersions
-        if (null != tlsVersions && tlsVersions.isNotEmpty()) {
+        if (!tlsVersions.isNullOrEmpty()) {
             builder.tlsVersions(*tlsVersions.toTypedArray())
         }
 
         val tlsCipherSuites = hsConfig.tlsCipherSuites
-        if (null != tlsCipherSuites && tlsCipherSuites.isNotEmpty()) {
+        if (!tlsCipherSuites.isNullOrEmpty()) {
             builder.cipherSuites(*tlsCipherSuites.toTypedArray())
         }