Update OpenVPN and add support for the new xkey infrastructure in OpenVPN

Signed-off-by: Arne Schwabe <arne@rfc2549.org>

7 files changed, 319 insertions, 93 deletions

diff --git a/main/src/main/cpp/CMakeLists.txt b/main/src/main/cpp/CMakeLists.txt
index 1a1176bd..04520267 100644
--- a/main/src/main/cpp/CMakeLists.txt
+++ b/main/src/main/cpp/CMakeLists.txt
@@ -104,6 +104,9 @@ target_compile_definitions(ovpnutil PRIVATE -DTARGET_ARCH_ABI=\"${ANDROID_ABI}\"
         )
 target_link_libraries(ovpnutil log)
 
+add_library(rsapss SHARED ovpnutil/rsapss.cpp)
+target_link_libraries(rsapss log crypto ssl)
+
 if (NOT ${CMAKE_LIBRARY_OUTPUT_DIRECTORY} MATCHES "build/intermediates/cmake/.*skeleton.*/")
     add_library(osslspeedtest SHARED ovpnutil/sslspeed.c)
     target_link_libraries(osslspeedtest log crypto ssl)
@@ -195,8 +198,8 @@ set(openvpn_srcs
         src/openvpn/tls_crypt.c
         src/openvpn/tun.c
         src/openvpn/vlan.c
-        #src/openvpn/xkey_helper.c
-        #src/openvpn/xkey_provider.c
+        src/openvpn/xkey_helper.c
+        src/openvpn/xkey_provider.c
         src/openvpn/comp-lz4.c
         src/openvpn/comp.c
         src/openvpn/compstub.c
diff --git a/main/src/main/cpp/openvpn b/main/src/main/cpp/openvpn
-Subproject e3831a62798d0324eb1e1badc1f199269a5baca
+Subproject cc43597350cb6f4ce89f23d2053dc58e0117456
diff --git a/main/src/main/cpp/openvpn-config/config.h b/main/src/main/cpp/openvpn-config/config.h
index 69ed58d3..7959c147 100644
--- a/main/src/main/cpp/openvpn-config/config.h
+++ b/main/src/main/cpp/openvpn-config/config.h
@@ -681,6 +681,4 @@ int res_init();
 #define HAVE_EVP_CIPHER_CTX_RESET
 
 
-#define _SOCKLEN_T_DECLARED 1
-
-//#define HAVE_XKEY_PROVIDER 1
\ No newline at end of file
+#define _SOCKLEN_T_DECLARED 1
\ No newline at end of file
diff --git a/main/src/main/cpp/ovpnutil/rsapss.cpp b/main/src/main/cpp/ovpnutil/rsapss.cpp
new file mode 100644
index 00000000..d6346811
--- /dev/null
+++ b/main/src/main/cpp/ovpnutil/rsapss.cpp
@@ -0,0 +1,146 @@
+/* Adapted from OpenSSL's rsa_pss.c from OpenSSL 3.0.1 */
+
+/*
+ * Copyright 2005-2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+#include "jni.h"
+
+#include <openssl/evp.h>
+#include <openssl/rand.h>
+#include <openssl/rsa.h>
+
+#include <array>
+
+static const unsigned char zeroes[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
+
+static char opensslerr[1024];
+extern "C" jbyteArray Java_de_blinkt_openvpn_core_NativeUtils_rsapss(JNIEnv *env,
+																	 jclass,
+																	 jint hashtype,
+																	 jint MSBits,
+																	 jint rsa_size,
+																	 jbyteArray from) {
+
+  /*
+  unsigned char *EM,
+				     const unsigned char *mHash,
+				     const EVP_MD *Hash, const EVP_MD *mgf1Hash,
+				     int sLen)
+*/
+
+  jbyte *data = env->GetByteArrayElements(from, NULL);
+  int datalen = env->GetArrayLength(from);
+
+  const auto *mHash = reinterpret_cast<const unsigned char *>(data);
+
+  const EVP_MD *Hash;
+
+  if (hashtype == 0) {
+	Hash = EVP_md5();
+  } else if (hashtype == 1) {
+	Hash = EVP_sha1();
+  } else if (hashtype == 2) {
+	Hash = EVP_sha224();
+  } else if (hashtype == 3) {
+	Hash = EVP_sha256();
+  } else if (hashtype == 4) {
+	Hash = EVP_sha384();
+  } else if (hashtype == 5) {
+	Hash = EVP_sha512();
+  }
+
+  const EVP_MD *mgf1Hash = Hash;
+
+  int ret = 0;
+  int maskedDBLen, emLen;
+  unsigned char *H, *salt = nullptr, *p;
+  EVP_MD_CTX *ctx = nullptr;
+
+  int hLen = EVP_MD_get_size(Hash);
+  int sLen = hLen; /* RSA_PSS_SALTLEN_DIGEST */
+
+  std::array<unsigned char, 2048> buf{};
+  unsigned char *EM = buf.data();
+
+  if (hLen < 0)
+	goto err;
+
+  emLen = rsa_size;
+  if (MSBits == 0) {
+	*EM++ = 0;
+	emLen--;
+  }
+  if (emLen < hLen + 2) {
+	goto err;
+  }
+  if (sLen == RSA_PSS_SALTLEN_MAX) {
+	sLen = emLen - hLen - 2;
+  } else if (sLen > emLen - hLen - 2) {
+	goto err;
+  }
+
+  if (sLen > 0) {
+	salt = (unsigned char *) OPENSSL_malloc(sLen);
+	if (salt == nullptr) {
+	  goto err;
+	}
+	if (RAND_bytes_ex(nullptr, salt, sLen, 0) <= 0)
+	  goto err;
+  }
+  maskedDBLen = emLen - hLen - 1;
+  H = EM + maskedDBLen;
+  ctx = EVP_MD_CTX_new();
+  if (ctx == nullptr)
+	goto err;
+  if (!EVP_DigestInit_ex(ctx, Hash, nullptr)
+	  || !EVP_DigestUpdate(ctx, zeroes, sizeof(zeroes))
+	  || !EVP_DigestUpdate(ctx, mHash, hLen))
+	goto err;
+  if (sLen && !EVP_DigestUpdate(ctx, salt, sLen))
+	goto err;
+  if (!EVP_DigestFinal_ex(ctx, H, nullptr))
+	goto err;
+
+  /* Generate dbMask in place then perform XOR on it */
+  if (PKCS1_MGF1(EM, maskedDBLen, H, hLen, mgf1Hash))
+	goto err;
+
+  p = EM;
+
+  /*
+   * Initial PS XORs with all zeroes which is a NOP so just update pointer.
+   * Note from a test above this value is guaranteed to be non-negative.
+   */
+  p += emLen - sLen - hLen - 2;
+  *p++ ^= 0x1;
+  if (sLen > 0) {
+	for (int i = 0; i < sLen; i++)
+	  *p++ ^= salt[i];
+  }
+  if (MSBits)
+	EM[0] &= 0xFF >> (8 - MSBits);
+
+  /* H is already in place so just set final 0xbc */
+
+  EM[emLen - 1] = 0xbc;
+
+  ret = 1;
+
+  err:
+  EVP_MD_CTX_free(ctx);
+  OPENSSL_clear_free(salt, (size_t) sLen); /* salt != NULL implies sLen > 0 */
+
+
+  jbyteArray jb;
+
+  jb = env->NewByteArray(emLen);
+
+  env->SetByteArrayRegion(jb, 0, emLen, (jbyte *) EM);
+
+  return jb;
+}
\ No newline at end of file
diff --git a/main/src/main/java/de/blinkt/openvpn/VpnProfile.java b/main/src/main/java/de/blinkt/openvpn/VpnProfile.java
index bac5939d..af85eeb1 100644
--- a/main/src/main/java/de/blinkt/openvpn/VpnProfile.java
+++ b/main/src/main/java/de/blinkt/openvpn/VpnProfile.java
@@ -41,6 +41,8 @@ import java.security.*;
 import java.security.cert.Certificate;
 import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
+import java.security.interfaces.RSAPrivateKey;
+import java.security.interfaces.RSAPublicKey;
 import java.security.spec.MGF1ParameterSpec;
 import java.security.spec.PSSParameterSpec;
 import java.util.Collection;
@@ -89,6 +91,9 @@ public class VpnProfile implements Serializable, Cloneable {
     private static final int AUTH_RETRY_NONE_KEEP = 1;
     private static final int AUTH_RETRY_INTERACT = 3;
     private static final String EXTRA_RSA_PADDING_TYPE = "de.blinkt.openvpn.api.RSA_PADDING_TYPE";
+    private static final String EXTRA_SALTLEN = "de.blinkt.openvpn.api.SALTLEN";
+    private static final String EXTRA_NEEDS_DIGEST = "de.blinkt.openvpn.api.NEEDS_DIGEST";
+    private static final String EXTRA_DIGEST = "de.blinkt.openvpn.api.DIGEST";
     public static String DEFAULT_DNS1 = "9.9.9.9";
     public static String DEFAULT_DNS2 = "2620:fe::fe";
     // variable named wrong and should haven beeen transient
@@ -302,7 +307,7 @@ public class VpnProfile implements Serializable, Cloneable {
     public void upgradeProfile() {
 
         /* Fallthrough is intended here */
-        switch(mProfileVersion) {
+        switch (mProfileVersion) {
             case 0:
             case 1:
                 /* default to the behaviour the OS used */
@@ -335,8 +340,7 @@ public class VpnProfile implements Serializable, Cloneable {
                 }
             case 9:
                 if (!TextUtils.isEmpty(mDataCiphers) &&
-                        mDataCiphers.toUpperCase(Locale.ROOT).contains("BF-CBC"))
-                {
+                        mDataCiphers.toUpperCase(Locale.ROOT).contains("BF-CBC")) {
                     mUseLegacyProvider = true;
                 }
             default:
@@ -507,8 +511,7 @@ public class VpnProfile implements Serializable, Cloneable {
                         if (!TextUtils.isEmpty(ks[1]))
                             cfg.append("<extra-certs>\n").append(ks[1]).append("\n</extra-certs>\n");
                         cfg.append("<cert>\n").append(ks[2]).append("\n</cert>\n");
-                        cfg.append("management-external-key nopadding pkcs1\n");
-                        // for xkey branch:" management-external-key pss digest
+                        cfg.append("management-external-key nopadding pkcs1 pss digest\n");
                     } else {
                         cfg.append(context.getString(R.string.keychain_access)).append("\n");
                         if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN)
@@ -527,8 +530,7 @@ public class VpnProfile implements Serializable, Cloneable {
                 }
         }
 
-        if (mCheckPeerFingerprint)
-        {
+        if (mCheckPeerFingerprint) {
             cfg.append("<peer-fingerprint>\n").append(mPeerFingerPrints).append("\n</peer-fingerprint>\n");
         }
 
@@ -672,10 +674,9 @@ public class VpnProfile implements Serializable, Cloneable {
             cfg.append("data-ciphers ").append(mDataCiphers).append("\n");
         }
 
-        if (mCompatMode > 0)
-        {
-            int major = mCompatMode/10000;
-            int minor = mCompatMode % 10000/100;
+        if (mCompatMode > 0) {
+            int major = mCompatMode / 10000;
+            int minor = mCompatMode % 10000 / 100;
             int patch = mCompatMode % 100;
             cfg.append(String.format(Locale.US, "compat-mode %d.%d.%d\n", major, minor, patch));
 
@@ -1067,9 +1068,8 @@ public class VpnProfile implements Serializable, Cloneable {
 
         if (!mUseLegacyProvider &&
                 (dataciphers.contains("BF-CBC")
-                || (mCompatMode > 0 && mCompatMode < 20500)
-                && cipher.equals("BF-CBC")))
-        {
+                        || (mCompatMode > 0 && mCompatMode < 20500)
+                        && cipher.equals("BF-CBC"))) {
             return R.string.bf_cbc_requires_legacy;
         }
 
@@ -1198,12 +1198,7 @@ public class VpnProfile implements Serializable, Cloneable {
         byte[] data = Base64.decode(b64data, Base64.DEFAULT);
         byte[] signed_bytes;
         if (mAuthenticationType == TYPE_EXTERNAL_APP) {
-            /* TODO: FIXME */
-            RsaPaddingType paddingType = (padding == OpenVPNManagement.SignaturePadding.RSA_PKCS1_PADDING) ? RsaPaddingType.PKCS1_PADDING : RsaPaddingType.NO_PADDING;
-            Bundle extra = new Bundle();
-            extra.putInt(EXTRA_RSA_PADDING_TYPE, paddingType.ordinal());
-
-            signed_bytes = getExtAppSignedData(c, data, extra);
+            signed_bytes = getExtAppSignedData(c, data, padding, saltlen, hashalg, needDigest);
         } else {
             signed_bytes = getKeyChainSignedData(data, padding, saltlen, hashalg, needDigest);
         }
@@ -1214,7 +1209,30 @@ public class VpnProfile implements Serializable, Cloneable {
             return null;
     }
 
-    private byte[] getExtAppSignedData(Context c, byte[] data, Bundle extra) {
+    private byte[] getExtAppSignedData(Context c, byte[] data, OpenVPNManagement.SignaturePadding padding, String saltlen, String hashalg, boolean needDigest)
+    {
+
+        Bundle extra = new Bundle();
+        RsaPaddingType paddingType;
+        switch (padding) {
+            case RSA_PKCS1_PADDING:
+                paddingType = RsaPaddingType.PKCS1_PADDING;
+                break;
+            case NO_PADDING:
+                paddingType = RsaPaddingType.NO_PADDING;
+                break;
+            case RSA_PKCS1_PSS_PADDING:
+                paddingType = RsaPaddingType.RSAPSS_PADDING;
+                break;
+            default:
+                paddingType = RsaPaddingType.NO_PADDING;
+        }
+
+        extra.putInt(EXTRA_RSA_PADDING_TYPE, paddingType.ordinal());
+        extra.putString(EXTRA_SALTLEN, saltlen);
+        extra.putString(EXTRA_DIGEST, hashalg);
+        extra.putBoolean(EXTRA_NEEDS_DIGEST, needDigest);
+
         if (TextUtils.isEmpty(mExternalAuthenticator))
             return null;
         try {
@@ -1227,12 +1245,6 @@ public class VpnProfile implements Serializable, Cloneable {
 
     private byte[] getKeyChainSignedData(byte[] data, OpenVPNManagement.SignaturePadding padding, String saltlen, String hashalg, boolean needDigest) {
         PrivateKey privkey = getKeystoreKey();
-        // The Jelly Bean *evil* Hack
-        // 4.2 implements the RSA/ECB/PKCS1PADDING in the OpenSSLprovider
-        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN) {
-            /* TODO: really fix this?! */
-            return processSignJellyBeans(privkey, data, padding);
-        }
 
 
         try {
@@ -1243,17 +1255,25 @@ public class VpnProfile implements Serializable, Cloneable {
             if (needDigest || keyalgorithm.equals("EC")) {
                 return doDigestSign(privkey, data, padding, hashalg, saltlen);
             } else {
-                                /* ECB is perfectly fine in this special case, since we are using it for
-               the public/private part in the TLS exchange
-             */
-                Cipher signer;
-                if (padding == OpenVPNManagement.SignaturePadding.RSA_PKCS1_PADDING)
-                    signer = Cipher.getInstance("RSA/ECB/PKCS1PADDING");
-                else if (padding == OpenVPNManagement.SignaturePadding.NO_PADDING)
-                    signer = Cipher.getInstance("RSA/ECB/NoPadding");
+                // The Jelly Bean *evil* Hack
+                // 4.2 implements the RSA/ECB/PKCS1PADDING in the OpenSSLprovider
+                if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN) {
+                    return processSignJellyBeans(privkey, data, padding);
+                }
 
-                else
-                    throw new NoSuchPaddingException("Unknown padding used for signature");
+             /* ECB is perfectly fine in this special case, since we are using it for
+                the public/private part in the TLS exchange */
+                Cipher signer = null;
+                switch (padding) {
+                    case RSA_PKCS1_PADDING:
+                        signer = Cipher.getInstance("RSA/ECB/PKCS1PADDING");
+                        break;
+                    case NO_PADDING:
+                        signer = Cipher.getInstance("RSA/ECB/NoPadding");
+                        break;
+                    case RSA_PKCS1_PSS_PADDING:
+                        throw new NoSuchPaddingException("Cannot do PKCS1 PSS padding without also doing the digest");
+                }
 
                 signer.init(Cipher.ENCRYPT_MODE, privkey);
 
@@ -1261,13 +1281,52 @@ public class VpnProfile implements Serializable, Cloneable {
 
                 return signed_bytes;
             }
-            } catch
-            (NoSuchAlgorithmException | InvalidKeyException | IllegalBlockSizeException | BadPaddingException | NoSuchPaddingException | SignatureException | InvalidAlgorithmParameterException
-            e){
-                VpnStatus.logError(R.string.error_rsa_sign, e.getClass().toString(), e.getLocalizedMessage());
-                return null;
-            }
+        } catch
+        (NoSuchAlgorithmException | InvalidKeyException | IllegalBlockSizeException | BadPaddingException | NoSuchPaddingException | SignatureException | InvalidAlgorithmParameterException
+                        e) {
+            VpnStatus.logError(R.string.error_rsa_sign, e.getClass().toString(), e.getLocalizedMessage());
+            return null;
         }
+    }
+
+    private byte[] addPSSPadding(PrivateKey privkey, String digest, byte[] data) throws NoSuchAlgorithmException {
+        /* For < API 23, add padding ourselves */
+        int hashtype = getHashtype(digest);
+
+        MessageDigest msgDigest = MessageDigest.getInstance(digest);
+        byte[] hash = msgDigest.digest(data);
+
+        /*  MSBits = (BN_num_bits(rsa->n) - 1) & 0x7; */
+        int numbits = ((RSAPrivateKey) privkey).getModulus().bitLength();
+
+        int MSBits = (numbits - 1) & 0x7;
+
+        return NativeUtils.addRssPssPadding(hashtype, MSBits, numbits/8, hash);
+    }
+
+    private int getHashtype(String digest) throws NoSuchAlgorithmException {
+        int hashtype = 0;
+        switch (digest) {
+            case "SHA1":
+                hashtype = 1;
+                break;
+            case "SHA224":
+                hashtype = 2;
+                break;
+            case "SHA256":
+                hashtype = 3;
+                break;
+            case "SHA384":
+                hashtype = 4;
+                break;
+            case "SHA512":
+                hashtype = 5;
+                break;
+            default:
+                throw new NoSuchAlgorithmException("Unknown digest algorithm: " + digest);
+        }
+        return hashtype;
+    }
 
     private byte[] doDigestSign(PrivateKey privkey, byte[] data, OpenVPNManagement.SignaturePadding padding, String hashalg, String saltlen) throws SignatureException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException {
         /* RSA */
@@ -1284,6 +1343,11 @@ public class VpnProfile implements Serializable, Cloneable {
             if (!"digest".equals(saltlen))
                 throw new SignatureException("PSS signing requires saltlen=digest");
 
+            if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
+                data = addPSSPadding(privkey, hashalg, data);
+                return getKeyChainSignedData(data, OpenVPNManagement.SignaturePadding.NO_PADDING, "none", "none", false);
+            }
+
             sig = Signature.getInstance(hashalg + "withRSA/PSS");
 
             PSSParameterSpec pssspec = null;
@@ -1308,62 +1372,63 @@ public class VpnProfile implements Serializable, Cloneable {
         return sig.sign();
     }
 
-    private byte[] processSignJellyBeans (PrivateKey privkey, byte[] data, OpenVPNManagement.SignaturePadding padding){
-            try {
-                boolean pkcs1padding=false;
-                if (padding == OpenVPNManagement.SignaturePadding.RSA_PKCS1_PADDING)
-                    pkcs1padding = true;
-                else if (padding != OpenVPNManagement.SignaturePadding.NO_PADDING)
-                    throw new IllegalAccessException("Unsuppoirted padding for jelly bean native signing");
+    private byte[] processSignJellyBeans(PrivateKey privkey, byte[] data, OpenVPNManagement.SignaturePadding padding) {
+        try {
+            boolean pkcs1padding = false;
+            if (padding == OpenVPNManagement.SignaturePadding.RSA_PKCS1_PADDING)
+                pkcs1padding = true;
+            else if (padding != OpenVPNManagement.SignaturePadding.NO_PADDING)
+                throw new IllegalAccessException("Unsuppoirted padding for jelly bean native signing");
 
-                Method getKey = privkey.getClass().getSuperclass().getDeclaredMethod("getOpenSSLKey");
-                getKey.setAccessible(true);
+            Method getKey = privkey.getClass().getSuperclass().getDeclaredMethod("getOpenSSLKey");
+            getKey.setAccessible(true);
 
-                // Real object type is OpenSSLKey
-                Object opensslkey = getKey.invoke(privkey);
+            // Real object type is OpenSSLKey
+            Object opensslkey = getKey.invoke(privkey);
 
-                getKey.setAccessible(false);
+            getKey.setAccessible(false);
 
-                Method getPkeyContext = opensslkey.getClass().getDeclaredMethod("getPkeyContext");
+            Method getPkeyContext = opensslkey.getClass().getDeclaredMethod("getPkeyContext");
 
-                // integer pointer to EVP_pkey
-                getPkeyContext.setAccessible(true);
-                int pkey = (Integer) getPkeyContext.invoke(opensslkey);
-                getPkeyContext.setAccessible(false);
+            // integer pointer to EVP_pkey
+            getPkeyContext.setAccessible(true);
+            int pkey = (Integer) getPkeyContext.invoke(opensslkey);
+            getPkeyContext.setAccessible(false);
 
-                // 112 with TLS 1.2 (172 back with 4.3), 36 with TLS 1.0
-                return NativeUtils.rsasign(data, pkey, pkcs1padding);
+            // 112 with TLS 1.2 (172 back with 4.3), 36 with TLS 1.0
+            return NativeUtils.rsasign(data, pkey, pkcs1padding);
 
-            } catch (NoSuchMethodException | InvalidKeyException | InvocationTargetException | IllegalAccessException | IllegalArgumentException e) {
-                VpnStatus.logError(R.string.error_rsa_sign, e.getClass().toString(), e.getLocalizedMessage());
-                return null;
-            }
+        } catch (NoSuchMethodException | InvalidKeyException | InvocationTargetException | IllegalAccessException | IllegalArgumentException e) {
+            VpnStatus.logError(R.string.error_rsa_sign, e.getClass().toString(), e.getLocalizedMessage());
+            return null;
         }
+    }
 
-        private boolean usesExtraProxyOptions () {
-            if (mUseCustomConfig && mCustomConfigOptions != null && mCustomConfigOptions.contains("http-proxy-option "))
+    private boolean usesExtraProxyOptions() {
+        if (mUseCustomConfig && mCustomConfigOptions != null && mCustomConfigOptions.contains("http-proxy-option "))
+            return true;
+        for (Connection c : mConnections)
+            if (c.usesExtraProxyOptions())
                 return true;
-            for (Connection c : mConnections)
-                if (c.usesExtraProxyOptions())
-                    return true;
 
-            return false;
-        }
+        return false;
+    }
 
-        /**
-         * The order of elements is important!
-         */
-        private enum RsaPaddingType {
-            NO_PADDING,
-            PKCS1_PADDING
-        }
+    /**
+     * The order of elements is important!
+     */
+    private enum RsaPaddingType {
+        NO_PADDING,
+        PKCS1_PADDING,
+        RSAPSS_PADDING
+    }
 
-        static class NoCertReturnedException extends Exception {
-            public NoCertReturnedException(String msg) {
-                super(msg);
-            }
+    static class NoCertReturnedException extends Exception {
+        public NoCertReturnedException(String msg) {
+            super(msg);
         }
     }
+}
 
 
 
diff --git a/main/src/main/java/de/blinkt/openvpn/core/NativeUtils.java b/main/src/main/java/de/blinkt/openvpn/core/NativeUtils.java
index ecfa86ff..470ec6d6 100644
--- a/main/src/main/java/de/blinkt/openvpn/core/NativeUtils.java
+++ b/main/src/main/java/de/blinkt/openvpn/core/NativeUtils.java
@@ -17,8 +17,7 @@ public class NativeUtils {
 
     static native void jniclose(int fdint);
 
-    public static String getNativeAPI()
-    {
+    public static String getNativeAPI() {
         if (isRoboUnitTest())
             return "ROBO";
         else
@@ -31,6 +30,20 @@ public class NativeUtils {
 
     public static native String getOpenVPN3GitVersion();
 
+    static boolean rsspssloaded = false;
+
+    public static byte[] addRssPssPadding(int hashtype, int MSBits, int rsa_size, byte[] from)
+    {
+        if (!rsspssloaded) {
+            rsspssloaded = true;
+            System.loadLibrary("rsapss");
+        }
+
+        return rsapss(hashtype, MSBits, rsa_size, from);
+    }
+
+    private static native byte[] rsapss(int hashtype, int MSBits, int rsa_size, byte[] from);
+
     public final static int[] openSSLlengths = {
         16, 64, 256, 1024, 1500, 8 * 1024, 16 * 1024
     };
@@ -43,6 +56,7 @@ public class NativeUtils {
             if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN)
                 System.loadLibrary("jbcrypto");
 
+
             if (!BuildConfig.FLAVOR.equals("skeleton")) {
                 System.loadLibrary("osslspeedtest");
             }
diff --git a/main/src/ui/java/de/blinkt/openvpn/fragments/Settings_Connections.kt b/main/src/ui/java/de/blinkt/openvpn/fragments/Settings_Connections.kt
index 75b87157..8ed9d9ef 100644
--- a/main/src/ui/java/de/blinkt/openvpn/fragments/Settings_Connections.kt
+++ b/main/src/ui/java/de/blinkt/openvpn/fragments/Settings_Connections.kt
@@ -50,8 +50,8 @@ class Settings_Connections : Settings_Fragment(), View.OnClickListener {
         mRecyclerView.layoutManager =
             LinearLayoutManager(activity, LinearLayoutManager.VERTICAL, false)
         mRecyclerView.adapter = mConnectionsAdapter
-        val fab_button = v.findViewById<View>(R.id.add_new_remote) as ImageButton
-        fab_button.setOnClickListener(this)
+        val fab_button = v.findViewById<View>(R.id.add_new_remote) as ImageButton?
+        fab_button?.setOnClickListener(this)
         mUseRandomRemote = v.findViewById<View>(R.id.remote_random) as Checkable
         mUseRandomRemote.isChecked = mProfile.mRemoteRandom
         mConnectionsAdapter.displayWarningIfNoneEnabled()