android: Add a simple HTTP(S) fetcher for CRLs

src/frontends/android/app/src/main/java/org/strongswan/android/logic/SimpleFetcher.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2017 Tobias Brunner
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+package org.strongswan.android.logic;
+
+import android.support.annotation.Keep;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+@Keep
+public class SimpleFetcher
+{
+	public static byte[] fetch(String uri) throws IOException
+	{
+		URL url = new URL(uri);
+		HttpURLConnection conn = (HttpURLConnection)url.openConnection();
+		conn.setConnectTimeout(10000);
+		conn.setReadTimeout(10000);
+		try
+		{
+			return streamToArray(conn.getInputStream());
+		}
+		finally
+		{
+			conn.disconnect();
+		}
+	}
+
+	private static byte[] streamToArray(InputStream in)
+	{
+		ByteArrayOutputStream out = new ByteArrayOutputStream();
+		byte[] buf = new byte[1024];
+		int len;
+
+		try
+		{
+			while ((len = in.read(buf)) != -1)
+			{
+				out.write(buf, 0, len);
+			}
+			return out.toByteArray();
+		}
+		catch (IOException e)
+		{
+			e.printStackTrace();
+		}
+		return null;
+	}
+}

src/frontends/android/app/src/main/jni/libandroidbridge/Android.mk

@@ -6,6 +6,7 @@ LOCAL_SRC_FILES := \
 android_jni.c \
 backend/android_attr.c \
 backend/android_creds.c \
+backend/android_fetcher.c \
 backend/android_dns_proxy.c \
 backend/android_private_key.c \
 backend/android_service.c \

src/frontends/android/app/src/main/jni/libandroidbridge/android_jni.c

@@ -44,6 +44,7 @@ static struct {
 
 jclass *android_charonvpnservice_class;
 jclass *android_charonvpnservice_builder_class;
+jclass *android_simple_fetcher_class;
 android_sdk_version_t android_sdk_version;
 
 /**
@@ -122,6 +123,9 @@ jint JNI_OnLoad(JavaVM *vm, void *reserved)
 	android_charonvpnservice_builder_class =
 				(*env)->NewGlobalRef(env, (*env)->FindClass(env,
 						JNI_PACKAGE_STRING "/CharonVpnService$BuilderAdapter"));
+	android_simple_fetcher_class =
+				(*env)->NewGlobalRef(env, (*env)->FindClass(env,
+						JNI_PACKAGE_STRING "/SimpleFetcher"));
 
 	jversion = (*env)->FindClass(env, "android/os/Build$VERSION");
 	jsdk_int = (*env)->GetStaticFieldID(env, jversion, "SDK_INT", "I");

src/frontends/android/app/src/main/jni/libandroidbridge/android_jni.h

@@ -44,6 +44,7 @@
  */
 extern jclass *android_charonvpnservice_class;
 extern jclass *android_charonvpnservice_builder_class;
+extern jclass *android_simple_fetcher_class;
 
 /**
  * Currently known (supported) SDK versions

src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_fetcher.c

@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2017 Tobias Brunner
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.  *
+ * 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.
+ */
+
+#include "android_fetcher.h"
+
+#include "../android_jni.h"
+#include "../charonservice.h"
+#include <utils/debug.h>
+
+typedef struct android_fetcher_t android_fetcher_t;
+
+struct android_fetcher_t {
+
+	/**
+	 * Public interface
+	 */
+	fetcher_t public;
+
+	/**
+	 * Callback function
+	 */
+	fetcher_callback_t cb;
+};
+
+METHOD(fetcher_t, fetch, status_t,
+	android_fetcher_t *this, char *uri, void *userdata)
+{
+	JNIEnv *env;
+	jmethodID method_id;
+	jobjectArray jdata;
+	jstring juri;
+	chunk_t data;
+	status_t status = FAILED;
+
+	if (this->cb == fetcher_default_callback)
+	{
+		*(chunk_t*)userdata = chunk_empty;
+	}
+
+	androidjni_attach_thread(&env);
+	/* can't use FindClass here as this is not called by the main thread */
+	method_id = (*env)->GetStaticMethodID(env, android_simple_fetcher_class,
+										  "fetch", "(Ljava/lang/String;)[B");
+	if (!method_id)
+	{
+		goto failed;
+	}
+	juri = (*env)->NewStringUTF(env, uri);
+	if (!juri)
+	{
+		goto failed;
+	}
+	jdata = (*env)->CallStaticObjectMethod(env, android_simple_fetcher_class,
+										   method_id, juri);
+	if (!jdata || androidjni_exception_occurred(env))
+	{
+		goto failed;
+	}
+	data = chunk_from_byte_array(env, jdata);
+	if (this->cb(userdata, data))
+	{
+		status = SUCCESS;
+	}
+	chunk_free(&data);
+	androidjni_detach_thread();
+	return status;
+
+failed:
+	DBG1(DBG_LIB, "failed to fetch from '%s'", uri);
+	androidjni_exception_occurred(env);
+	androidjni_detach_thread();
+	return FAILED;
+}
+
+METHOD(fetcher_t, set_option, bool,
+	android_fetcher_t *this, fetcher_option_t option, ...)
+{
+	bool supported = TRUE;
+	va_list args;
+
+	va_start(args, option);
+	switch (option)
+	{
+		case FETCH_CALLBACK:
+		{
+			this->cb = va_arg(args, fetcher_callback_t);
+			break;
+		}
+		default:
+			supported = FALSE;
+			break;
+	}
+	va_end(args);
+	return supported;
+}
+
+METHOD(fetcher_t, destroy, void,
+	android_fetcher_t *this)
+{
+	free(this);
+}
+
+/*
+ * Described in header.
+ */
+fetcher_t *android_fetcher_create()
+{
+	android_fetcher_t *this;
+
+	INIT(this,
+		.public = {
+			.fetch = _fetch,
+			.set_option = _set_option,
+			.destroy = _destroy,
+		},
+		.cb = fetcher_default_callback,
+	);
+
+	return &this->public;
+}

src/frontends/android/app/src/main/jni/libandroidbridge/backend/android_fetcher.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2017 Tobias Brunner
+ * HSR Hochschule fuer Technik Rapperswil
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup android_fetcher android_fetcher
+ * @{ @ingroup android_backend
+ */
+
+#ifndef ANDROID_FETCHER_H_
+#define ANDROID_FETCHER_H_
+
+#include <library.h>
+
+/**
+ * Create an Android-specific fetcher instance based on SimpleFetcher
+ *
+ * @return						fetcher_t instance
+ */
+fetcher_t *android_fetcher_create();
+
+#endif /** ANDROID_FETCHER_H_ @}*/

src/frontends/android/app/src/main/jni/libandroidbridge/charonservice.c

@@ -1,8 +1,8 @@
 /*
- * Copyright (C) 2012-2015 Tobias Brunner
+ * Copyright (C) 2012-2017 Tobias Brunner
  * Copyright (C) 2012 Giuliano Grassi
  * Copyright (C) 2012 Ralf Sager
- * Hochschule fuer Technik Rapperswil
+ * HSR Hochschule fuer Technik Rapperswil
  *
  * 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
@@ -25,6 +25,7 @@
 #include "android_jni.h"
 #include "backend/android_attr.h"
 #include "backend/android_creds.h"
+#include "backend/android_fetcher.h"
 #include "backend/android_private_key.h"
 #include "backend/android_service.h"
 #include "kernel/android_ipsec.h"
@@ -523,6 +524,9 @@ static void charonservice_init(JNIEnv *env, jobject service, jobject builder,
 		PLUGIN_CALLBACK(charonservice_register, NULL),
 			PLUGIN_PROVIDE(CUSTOM, "android-backend"),
 				PLUGIN_DEPENDS(CUSTOM, "libcharon"),
+		PLUGIN_REGISTER(FETCHER, android_fetcher_create),
+			PLUGIN_PROVIDE(FETCHER, "http://"),
+			PLUGIN_PROVIDE(FETCHER, "https://"),
 	};
 
 	INIT(this,