Merge branch 'certificate_transition' into 'master'

Certificate transition

See merge request leap/bitmask_android!155

5 files changed, 74 insertions, 116 deletions

diff --git a/app/src/main/java/se/leap/bitmaskclient/base/utils/ConfigHelper.java b/app/src/main/java/se/leap/bitmaskclient/base/utils/ConfigHelper.java
index 6c242e5a..27943022 100644
--- a/app/src/main/java/se/leap/bitmaskclient/base/utils/ConfigHelper.java
+++ b/app/src/main/java/se/leap/bitmaskclient/base/utils/ConfigHelper.java
@@ -37,6 +37,7 @@ import java.security.KeyFactory;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
+import java.security.cert.Certificate;
 import java.security.cert.CertificateEncodingException;
 import java.security.cert.CertificateException;
 import java.security.cert.CertificateFactory;
@@ -44,7 +45,9 @@ import java.security.cert.X509Certificate;
 import java.security.interfaces.RSAPrivateKey;
 import java.security.spec.InvalidKeySpecException;
 import java.security.spec.PKCS8EncodedKeySpec;
+import java.util.ArrayList;
 import java.util.Calendar;
+import java.util.Collection;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -99,25 +102,28 @@ public class ConfigHelper {
         return ret;
     }
 
-    public static X509Certificate parseX509CertificateFromString(String certificateString) {
-        java.security.cert.Certificate certificate = null;
+    public static ArrayList<X509Certificate> parseX509CertificatesFromString(String certificateString) {
+        Collection<? extends Certificate> certificates;
         CertificateFactory cf;
         try {
             cf = CertificateFactory.getInstance("X.509");
 
-            certificateString = certificateString.replaceFirst("-----BEGIN CERTIFICATE-----", "").replaceFirst("-----END CERTIFICATE-----", "").trim();
-            byte[] cert_bytes = Base64.decode(certificateString);
-            InputStream caInput = new ByteArrayInputStream(cert_bytes);
-            try {
-                certificate = cf.generateCertificate(caInput);
-                System.out.println("ca=" + ((X509Certificate) certificate).getSubjectDN());
-            } finally {
-                caInput.close();
+            certificateString = certificateString.replaceAll("-----BEGIN CERTIFICATE-----", "").trim().replaceAll("-----END CERTIFICATE-----", "").trim();
+            byte[] certBytes = Base64.decode(certificateString);
+            try (InputStream caInput = new ByteArrayInputStream(certBytes)) {
+                certificates = cf.generateCertificates(caInput);
+                if (certificates != null) {
+                    for (Certificate cert : certificates) {
+                        System.out.println("ca=" + ((X509Certificate) cert).getSubjectDN());
+                    }
+                    return (ArrayList<X509Certificate>) certificates;
+                }
             }
-        } catch (NullPointerException | CertificateException | IOException | IllegalArgumentException e) {
-            return null;
+        } catch (NullPointerException | CertificateException | IOException | IllegalArgumentException | ClassCastException e) {
+            e.printStackTrace();
         }
-        return (X509Certificate) certificate;
+
+        return null;
     }
 
     public static RSAPrivateKey parseRsaKeyFromString(String rsaKeyString) {
diff --git a/app/src/main/java/se/leap/bitmaskclient/base/utils/KeyStoreHelper.java b/app/src/main/java/se/leap/bitmaskclient/base/utils/KeyStoreHelper.java
deleted file mode 100644
index b0b28993..00000000
--- a/app/src/main/java/se/leap/bitmaskclient/base/utils/KeyStoreHelper.java
+++ /dev/null
@@ -1,78 +0,0 @@
-package se.leap.bitmaskclient.base.utils;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.security.KeyStore;
-import java.security.KeyStoreException;
-import java.security.NoSuchAlgorithmException;
-import java.security.cert.CertificateException;
-import java.security.cert.CertificateFactory;
-import java.security.cert.X509Certificate;
-
-/**
- * Created by cyberta on 18.03.18.
- */
-
-public class KeyStoreHelper {
-    private static KeyStore trustedKeystore;
-
-    /**
-     * Adds a new X509 certificate given its input stream and its provider name
-     *
-     * @param provider    used to store the certificate in the keystore
-     * @param inputStream from which X509 certificate must be generated.
-     */
-    public static void addTrustedCertificate(String provider, InputStream inputStream) {
-        CertificateFactory cf;
-        try {
-            cf = CertificateFactory.getInstance("X.509");
-            X509Certificate cert =
-                    (X509Certificate) cf.generateCertificate(inputStream);
-            trustedKeystore.setCertificateEntry(provider, cert);
-        } catch (CertificateException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        } catch (KeyStoreException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        }
-    }
-
-    /**
-     * Adds a new X509 certificate given in its string from and using its provider name
-     *
-     * @param provider    used to store the certificate in the keystore
-     * @param certificate
-     */
-    public static void addTrustedCertificate(String provider, String certificate) {
-
-        try {
-            X509Certificate cert = ConfigHelper.parseX509CertificateFromString(certificate);
-            if (trustedKeystore == null) {
-                trustedKeystore = KeyStore.getInstance("BKS");
-                trustedKeystore.load(null);
-            }
-            trustedKeystore.setCertificateEntry(provider, cert);
-        } catch (KeyStoreException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        } catch (NoSuchAlgorithmException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        } catch (CertificateException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        } catch (IOException e) {
-            // TODO Auto-generated catch block
-            e.printStackTrace();
-        }
-    }
-
-    /**
-     * @return class wide keystore
-     */
-    public static KeyStore getKeystore() {
-        return trustedKeystore;
-    }
-
-}
diff --git a/app/src/main/java/se/leap/bitmaskclient/eip/VpnCertificateValidator.java b/app/src/main/java/se/leap/bitmaskclient/eip/VpnCertificateValidator.java
index c747b731..16d1c5ad 100644
--- a/app/src/main/java/se/leap/bitmaskclient/eip/VpnCertificateValidator.java
+++ b/app/src/main/java/se/leap/bitmaskclient/eip/VpnCertificateValidator.java
@@ -16,9 +16,12 @@
  */
 package se.leap.bitmaskclient.eip;
 
+import androidx.annotation.VisibleForTesting;
+
 import java.security.cert.CertificateExpiredException;
 import java.security.cert.CertificateNotYetValidException;
 import java.security.cert.X509Certificate;
+import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Date;
 
@@ -27,7 +30,7 @@ import se.leap.bitmaskclient.base.utils.ConfigHelper;
 public class VpnCertificateValidator {
     public final static String TAG = VpnCertificateValidator.class.getSimpleName();
 
-    private String certificate;
+    private final String certificate;
     private CalendarProviderInterface calendarProvider;
 
     public VpnCertificateValidator(String certificate) {
@@ -35,21 +38,30 @@ public class VpnCertificateValidator {
         this.calendarProvider = new CalendarProvider();
     }
 
+    @VisibleForTesting
     public void setCalendarProvider(CalendarProviderInterface calendarProvider) {
         this.calendarProvider = calendarProvider;
     }
 
     /**
      *
-     * @return true if there's a certificate that is valid for more than 15 more days
+     * @return true if all certificates are valid for more than 15 more days
      */
     public boolean isValid() {
         if (certificate.isEmpty()) {
             return false;
         }
 
-        X509Certificate x509Certificate = ConfigHelper.parseX509CertificateFromString(certificate);
-        return isValid(x509Certificate);
+        ArrayList<X509Certificate> x509Certificates = ConfigHelper.parseX509CertificatesFromString(certificate);
+        if (x509Certificates == null) {
+            return false;
+        }
+        for (X509Certificate cert : x509Certificates) {
+            if (!isValid(cert)) {
+                return false;
+            }
+        }
+        return true;
     }
 
 
diff --git a/app/src/main/java/se/leap/bitmaskclient/providersetup/ProviderApiManagerBase.java b/app/src/main/java/se/leap/bitmaskclient/providersetup/ProviderApiManagerBase.java
index 808d9e75..63cf03cf 100644
--- a/app/src/main/java/se/leap/bitmaskclient/providersetup/ProviderApiManagerBase.java
+++ b/app/src/main/java/se/leap/bitmaskclient/providersetup/ProviderApiManagerBase.java
@@ -849,18 +849,24 @@ public abstract class ProviderApiManagerBase {
     protected boolean validCertificate(Provider provider, String certString) {
         boolean result = false;
         if (!ConfigHelper.checkErroneousDownload(certString)) {
-            X509Certificate certificate = ConfigHelper.parseX509CertificateFromString(certString);
+            ArrayList<X509Certificate> certificates = ConfigHelper.parseX509CertificatesFromString(certString);
             try {
-                if (certificate != null) {
-                    JSONObject providerJson = provider.getDefinition();
-                    String fingerprint = providerJson.getString(Provider.CA_CERT_FINGERPRINT);
-                    String encoding = fingerprint.split(":")[0];
-                    String expectedFingerprint = fingerprint.split(":")[1];
-                    String realFingerprint = getFingerprintFromCertificate(certificate, encoding);
-
-                    result = realFingerprint.trim().equalsIgnoreCase(expectedFingerprint.trim());
-                } else
+                if (certificates != null) {
+                    if (certificates.size() == 1) {
+                        JSONObject providerJson = provider.getDefinition();
+                        String fingerprint = providerJson.getString(Provider.CA_CERT_FINGERPRINT);
+                        String encoding = fingerprint.split(":")[0];
+                        String expectedFingerprint = fingerprint.split(":")[1];
+                        String realFingerprint = getFingerprintFromCertificate(certificates.get(0), encoding);
+                        result = realFingerprint.trim().equalsIgnoreCase(expectedFingerprint.trim());
+                    } else {
+                        // otherwise we assume the provider is transitioning the CA certs and thus shipping multiple CA certs
+                        // in that case we don't do cert pinning
+                        result = true;
+                    }
+                } else {
                     result = false;
+                }
             } catch (JSONException | NoSuchAlgorithmException | CertificateEncodingException e) {
                 result = false;
             }
@@ -910,18 +916,24 @@ public abstract class ProviderApiManagerBase {
             return result;
         }
 
-        X509Certificate certificate = ConfigHelper.parseX509CertificateFromString(caCert);
-        if (certificate == null) {
+        ArrayList<X509Certificate> certificates = ConfigHelper.parseX509CertificatesFromString(caCert);
+        if (certificates == null) {
             return setErrorResult(result, warning_corrupted_provider_cert, ERROR_INVALID_CERTIFICATE.toString());
         }
         try {
-            certificate.checkValidity();
             String encoding = provider.getCertificatePinEncoding();
             String expectedFingerprint = provider.getCertificatePin();
 
-            String realFingerprint = getFingerprintFromCertificate(certificate, encoding);
-            if (!realFingerprint.trim().equalsIgnoreCase(expectedFingerprint.trim())) {
-                return setErrorResult(result, warning_corrupted_provider_cert, ERROR_CERTIFICATE_PINNING.toString());
+            // Do certificate pinning only if we have 1 cert, otherwise we assume some transitioning of
+            // X509 certs, therefore we cannot do cert pinning
+            if (certificates.size() == 1) {
+                String realFingerprint = getFingerprintFromCertificate(certificates.get(0), encoding);
+                if (!realFingerprint.trim().equalsIgnoreCase(expectedFingerprint.trim())) {
+                    return setErrorResult(result, warning_corrupted_provider_cert, ERROR_CERTIFICATE_PINNING.toString());
+                }
+            }
+            for (X509Certificate certificate : certificates) {
+                certificate.checkValidity();
             }
 
             if (!canConnect(provider, result)) {
@@ -1073,9 +1085,9 @@ public abstract class ProviderApiManagerBase {
             keyString = Base64.encodeToString(key.getEncoded(), Base64.DEFAULT);
             provider.setPrivateKey( "-----BEGIN RSA PRIVATE KEY-----\n" + keyString + "-----END RSA PRIVATE KEY-----");
 
-            X509Certificate certificate = ConfigHelper.parseX509CertificateFromString(certificateString);
-            certificate.checkValidity();
-            certificateString = Base64.encodeToString(certificate.getEncoded(), Base64.DEFAULT);
+            ArrayList<X509Certificate> certificates = ConfigHelper.parseX509CertificatesFromString(certificateString);
+            certificates.get(0).checkValidity();
+            certificateString = Base64.encodeToString(certificates.get(0).getEncoded(), Base64.DEFAULT);
             provider.setVpnCertificate( "-----BEGIN CERTIFICATE-----\n" + certificateString + "-----END CERTIFICATE-----");
             result.putBoolean(BROADCAST_RESULT_KEY, true);
         } catch (CertificateException | NullPointerException e) {
diff --git a/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/TLSCompatSocketFactory.java b/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/TLSCompatSocketFactory.java
index 5357fd74..cc68b5a8 100644
--- a/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/TLSCompatSocketFactory.java
+++ b/app/src/main/java/se/leap/bitmaskclient/providersetup/connectivity/TLSCompatSocketFactory.java
@@ -12,6 +12,8 @@ import java.security.KeyStoreException;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
 import java.security.cert.CertificateException;
+import java.security.cert.X509Certificate;
+import java.util.ArrayList;
 import java.util.Arrays;
 
 import javax.net.ssl.SSLContext;
@@ -55,8 +57,12 @@ public class TLSCompatSocketFactory extends SSLSocketFactory {
         KeyStore keyStore = KeyStore.getInstance(defaultType);
         keyStore.load(null, null);
         if (!TextUtils.isEmpty(trustedSelfSignedCaCert)) {
-            java.security.cert.Certificate provider_certificate = ConfigHelper.parseX509CertificateFromString(trustedSelfSignedCaCert);
-            keyStore.setCertificateEntry("provider_ca_certificate", provider_certificate);
+            ArrayList<X509Certificate> x509Certificates = ConfigHelper.parseX509CertificatesFromString(trustedSelfSignedCaCert);
+            if (x509Certificates != null) {
+                for (int i = 0; i < x509Certificates.size(); i++) {
+                    keyStore.setCertificateEntry("provider_ca_certificate"+i, x509Certificates.get(i));
+                }
+            }
         }
 
         // Create a TrustManager that trusts the CAs in our KeyStore