/**
* Copyright (c) 2018 LEAP Encryption Access Project and contributers
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
package se.leap.bitmaskclient;
import android.content.SharedPreferences;
import android.content.res.Resources;
import android.os.Bundle;
import android.util.Pair;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.IOException;
import java.net.URL;
import java.util.List;
import okhttp3.OkHttpClient;
import se.leap.bitmaskclient.eip.EIP;
import static android.text.TextUtils.isEmpty;
import static se.leap.bitmaskclient.Constants.BROADCAST_RESULT_KEY;
import static se.leap.bitmaskclient.Constants.PROVIDER_VPN_CERTIFICATE;
import static se.leap.bitmaskclient.ProviderAPI.ERRORS;
import static se.leap.bitmaskclient.ProviderSetupFailedDialog.DOWNLOAD_ERRORS.ERROR_CERTIFICATE_PINNING;
import static se.leap.bitmaskclient.ProviderSetupFailedDialog.DOWNLOAD_ERRORS.ERROR_CORRUPTED_PROVIDER_JSON;
import static se.leap.bitmaskclient.R.string.downloading_vpn_certificate_failed;
import static se.leap.bitmaskclient.R.string.error_io_exception_user_message;
import static se.leap.bitmaskclient.R.string.malformed_url;
import static se.leap.bitmaskclient.R.string.warning_corrupted_provider_cert;
import static se.leap.bitmaskclient.R.string.warning_corrupted_provider_details;
/**
* Implements the logic of the provider api http requests. The methods of this class need to be called from
* a background thread.
*/
public class ProviderApiManager extends ProviderApiManagerBase {
public ProviderApiManager(SharedPreferences preferences, Resources resources, OkHttpClientGenerator clientGenerator, ProviderApiServiceCallback callback) {
super(preferences, resources, clientGenerator, callback);
}
/**
* Only used in insecure flavor.
*/
static boolean lastDangerOn() {
return false;
}
/**
* Downloads a provider.json from a given URL, adding a new provider using the given name.
*
* @param task containing a boolean meaning if the provider is custom or not, another boolean meaning if the user completely trusts this provider, the provider name and its provider.json url.
* @return a bundle with a boolean value mapped to a key named BROADCAST_RESULT_KEY, and which is true if the update was successful.
*/
@Override
protected Bundle setUpProvider(Provider provider, Bundle task) {
Bundle currentDownload = new Bundle();
if (isEmpty(provider.getMainUrlString()) || provider.getMainUrl().isDefault()) {
currentDownload.putBoolean(BROADCAST_RESULT_KEY, false);
setErrorResult(currentDownload, malformed_url, null);
return currentDownload;
}
getPersistedProviderUpdates(provider);
currentDownload = validateProviderDetails(provider);
//provider details invalid
if (currentDownload.containsKey(ERRORS)) {
return currentDownload;
}
//no provider certificate available
if (currentDownload.containsKey(BROADCAST_RESULT_KEY) && !currentDownload.getBoolean(BROADCAST_RESULT_KEY)) {
resetProviderDetails(provider);
}
if (!provider.hasDefinition()) {
currentDownload = getAndSetProviderJson(provider);
}
if (provider.hasDefinition() || (currentDownload.containsKey(BROADCAST_RESULT_KEY) && currentDownload.getBoolean(BROADCAST_RESULT_KEY))) {
if (!provider.hasCaCert())
currentDownload = downloadCACert(provider);
if (provider.hasCaCert() || (currentDownload.containsKey(BROADCAST_RESULT_KEY) && currentDownload.getBoolean(BROADCAST_RESULT_KEY))) {
currentDownload = getAndSetEipServiceJson(provider);
}
}
return currentDownload;
}
private Bundle getAndSetProviderJson(Provider provider) {
Bundle result = new Bundle();
String caCert = provider.getCaCert();
JSONObject providerDefinition = provider.getDefinition();
String providerDotJsonString;
if(providerDefinition.length() == 0 || caCert.isEmpty()) {
String providerJsonUrl = provider.getMainUrlString() + "/provider.json";
providerDotJsonString = downloadWithCommercialCA(providerJsonUrl, provider);
} else {
providerDotJsonString = downloadFromApiUrlWithProviderCA("/provider.json", caCert, providerDefinition);
}
if (!isValidJson(providerDotJsonString)) {
setErrorResult(result, malformed_url, null);
return result;
}
try {
JSONObject providerJson = new JSONObject(providerDotJsonString);
if (provider.define(providerJson)) {
result.putBoolean(BROADCAST_RESULT_KEY, true);
} else {
return setErrorResult(result, warning_corrupted_provider_details, ERROR_CORRUPTED_PROVIDER_JSON.toString());
}
} catch (JSONException e) {
String reason_to_fail = pickErrorMessage(providerDotJsonString);
result.putString(ERRORS, reason_to_fail);
result.putBoolean(BROADCAST_RESULT_KEY, false);
}
return result;
}
/**
* Downloads the eip-service.json from a given URL, and saves eip service capabilities including the offered gateways
* @return a bundle with a boolean value mapped to a key named BROADCAST_RESULT_KEY, and which is true if the download was successful.
*/
@Override
protected Bundle getAndSetEipServiceJson(Provider provider) {
Bundle result = new Bundle();
String eipServiceJsonString = "";
try {
JSONObject providerJson = provider.getDefinition();
String eipServiceUrl = providerJson.getString(Provider.API_URL) + "/" + providerJson.getString(Provider.API_VERSION) + "/" + EIP.SERVICE_API_PATH;
eipServiceJsonString = downloadWithProviderCA(provider.getCaCert(), eipServiceUrl);
JSONObject eipServiceJson = new JSONObject(eipServiceJsonString);
eipServiceJson.getInt(Provider.API_RETURN_SERIAL);
provider.setEipServiceJson(eipServiceJson);
result.putBoolean(BROADCAST_RESULT_KEY, true);
} catch (NullPointerException | JSONException e) {
String reasonToFail = pickErrorMessage(eipServiceJsonString);
result.putString(ERRORS, reasonToFail);
result.putBoolean(BROADCAST_RESULT_KEY, false);
}
return result;
}
/**
* Downloads a new OpenVPN certificate, attaching authenticated cookie for authenticated certificate.
*
* @return true if certificate was downloaded correctly, false if provider.json is not present in SharedPreferences, or if the certificate url could not be parsed as a URI, or if there was an SSL error.
*/
@Override
protected Bundle updateVpnCertificate(Provider provider) {
Bundle result = new Bundle();
try {
JSONObject providerJson = provider.getDefinition();
String providerMainUrl = providerJson.getString(Provider.API_URL);
URL newCertStringUrl = new URL(providerMainUrl + "/" + providerJson.getString(Provider.API_VERSION) + "/" + PROVIDER_VPN_CERTIFICATE);
String certString = downloadWithProviderCA(provider.getCaCert(), newCertStringUrl.toString());
if (ConfigHelper.checkErroneousDownload(certString)) {
if (certString == null || certString.isEmpty()) {
// probably 204
setErrorResult(result, error_io_exception_user_message, null);
} else {
String reasonToFail = pickErrorMessage(certString);
result.putString(ERRORS, reasonToFail);
result.putBoolean(BROADCAST_RESULT_KEY, false);
return result;
}
}
return loadCertificate(provider, certString);
} catch (IOException | JSONException e) {
// TODO try to get Provider Json
setErrorResult(result, downloading_vpn_certificate_failed, null);
e.printStackTrace();
}
return result;
}
private Bundle downloadCACert(Provider provider) {
Bundle result = new Bundle();
try {
String caCertUrl = provider.getDefinition().getString(Provider.CA_CERT_URI);
String providerDomain = getDomainFromMainURL(provider.getMainUrlString());
String certString = downloadWithCommercialCA(caCertUrl, provider);
if (validCertificate(provider, certString)) {
provider.setCaCert(certString);
preferences.edit().putString(Provider.CA_CERT + "." + providerDomain, certString).apply();
result.putBoolean(BROADCAST_RESULT_KEY, true);
} else {
setErrorResult(result, warning_corrupted_provider_cert, ERROR_CERTIFICATE_PINNING.toString());
}
} catch (JSONException e) {
e.printStackTrace();
}
return result;
}
/**
* Tries to download the contents of the provided url using commercially validated CA certificate from chosen provider.
*
*/
private String downloadWithCommercialCA(String stringUrl, Provider provider) {
String responseString;
JSONObject errorJson = new JSONObject();
OkHttpClient okHttpClient = clientGenerator.initCommercialCAHttpClient(errorJson);
if (okHttpClient == null) {
return errorJson.toString();
}
List> headerArgs = getAuthorizationHeader();
responseString = sendGetStringToServer(stringUrl, headerArgs, okHttpClient);
if (responseString != null && responseString.contains(ERRORS)) {
try {
// try to download with provider CA on certificate error
JSONObject responseErrorJson = new JSONObject(responseString);
if (responseErrorJson.getString(ERRORS).equals(resources.getString(R.string.certificate_error))) {
responseString = downloadWithProviderCA(provider.getCaCert(), stringUrl);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
return responseString;
}
/**
* Tries to download the contents of the provided url using not commercially validated CA certificate from chosen provider.
*
* @return an empty string if it fails, the response body if not.
*/
private String downloadFromApiUrlWithProviderCA(String path, String caCert, JSONObject providerDefinition) {
String responseString;
JSONObject errorJson = new JSONObject();
String baseUrl = getApiUrl(providerDefinition);
OkHttpClient okHttpClient = clientGenerator.initSelfSignedCAHttpClient(caCert, errorJson);
if (okHttpClient == null) {
return errorJson.toString();
}
String urlString = baseUrl + path;
List> headerArgs = getAuthorizationHeader();
responseString = sendGetStringToServer(urlString, headerArgs, okHttpClient);
return responseString;
}
/**
* Tries to download the contents of the provided url using not commercially validated CA certificate from chosen provider.
*
* @param urlString as a string
* @return an empty string if it fails, the url content if not.
*/
private String downloadWithProviderCA(String caCert, String urlString) {
JSONObject initError = new JSONObject();
String responseString;
OkHttpClient okHttpClient = clientGenerator.initSelfSignedCAHttpClient(caCert, initError);
if (okHttpClient == null) {
return initError.toString();
}
List> headerArgs = getAuthorizationHeader();
responseString = sendGetStringToServer(urlString, headerArgs, okHttpClient);
return responseString;
}
}