SockStatUtil.java

/*
 SockStatUtil.java
 Copyright (c) 2015 NTT DOCOMO,INC.
 Released under the MIT license
 http://opensource.org/licenses/mit-license.php
 */
package org.deviceconnect.android.observer.util;

import android.content.Context;
import android.support.annotation.NonNull;

import org.deviceconnect.android.manager.BuildConfig;

import java.io.File;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.StringTokenizer;

/**
 * Androidが使用しているSocketの状態を持つファイルを解析するユーティリティクラス.
 *
 * @author NTT DOCOMO, INC.
 *
 */
public final class SockStatUtil {
    /**
     * Sockstatファイルのローカルポート.
     */
    private static final int LOCAL_IP_PORT = 1;
    /**
     * Sockstatファイルのリモートポート.
     */
    private static final int REMOTE_IP_PORT = 2;
    /**
     * Sockstatファイルの接続状況.
     */
    private static final int CONNECTION_STATE = 3;
    /**
     * SockstatファイルのUID.
     */
    private static final int UID = 7;
    /**
     * 16進数.
     */
    private static final int HEX = 16;
    /**
     * IPの16進数の文字列長.
     */
    private static final int IP_HEX_LENGTH = 8;
    /**
     * IPの10進数の文字列長.
     */
    private static final int IP_DECIMAL_LENGTH = 4;
    /**
     * コンストラクタ.
     */
    private SockStatUtil() {
    }

    /**
     * SockstatファイルのSocketのリストを取得する.
     * @param context context
     * @return socket list
     */
    public static synchronized ArrayList<AndroidSocket> getSocketList(final Context context) {
        ArrayList<AndroidSocket> allSocketList = new ArrayList<>();
        if (context == null) {
            return allSocketList;
        }
        allSocketList.addAll(parseProcNetFile("/proc/net/tcp6", SocketType.TCP));
        allSocketList.addAll(parseProcNetFile("/proc/net/tcp", SocketType.TCP));
        allSocketList.addAll(parseProcNetFile("/proc/net/udp6", SocketType.UDP));
        allSocketList.addAll(parseProcNetFile("/proc/net/udp", SocketType.UDP));
        processAppInfo(context, allSocketList);
        return allSocketList;
    }

    /**
     * 指定されたSockstatファイルの解析を行う.
     * @param procFileName 解析するファイル名
     * @param socketType 解析するSocketのタイプ
     * @return Socketリスト
     */
    private static ArrayList<AndroidSocket> parseProcNetFile(final String procFileName, final SocketType socketType) {
        ArrayList<AndroidSocket> sockets = new ArrayList<>();
        if (procFileName == null) {
            return sockets;
        }

        Scanner scanner = null;
        File file = new File(procFileName);
        try {
            scanner = new Scanner(file);
            scanner.nextLine();
            while (scanner.hasNext()) {
                sockets.add(getAndroidSocket(socketType, scanner.nextLine()));
            }
        } catch (Exception e) {
            if (BuildConfig.DEBUG) {
                e.printStackTrace();
            }
        } finally {
            if (scanner != null) {
                scanner.close();
            }
        }
        return sockets;
    }

    @NonNull
    private static AndroidSocket getAndroidSocket(final SocketType socketType, final String nextLine) {
        AndroidSocket aSocket = new AndroidSocket();
        aSocket.setType(socketType);
        StringTokenizer tokenizer = new StringTokenizer(nextLine);
        int tokenNo = 0;
        do {
            String token = tokenizer.nextToken();
            switch (tokenNo) {
                case LOCAL_IP_PORT:  // Analysis of Local IP and Port number
                    String[] localAddress = token.split(":");
                    if (localAddress.length <= 1) {
                        break;
                    }
                    aSocket.setLocalAddress(convertIPtoString(localAddress[0]));
                    aSocket.setLocalPort(Integer.parseInt(localAddress[1], HEX));
                    break;
                case REMOTE_IP_PORT: // Analysis of Remote IP and Port number
                    String[] remoteAddress = token.split(":");
                    if (remoteAddress.length <= 1) {
                        break;
                    }
                    aSocket.setRemoteAddress(convertIPtoString(remoteAddress[0]));
                    aSocket.setRemotePort(Integer.parseInt(remoteAddress[1], HEX));
                    break;
                case CONNECTION_STATE: //Connection status
                    if (socketType == SocketType.TCP) {
                        int l = Integer.parseInt(token, HEX);
                        if (l > SocketState.values().length || l < 0) {
                            l = 0;
                        }
                        aSocket.setState(SocketState.values()[l]);
                    } else {
                        aSocket.setState(SocketState.UDP_LISTEN);
                    }
                    break;
                case UID: //Uid of occupancy to the program
                    aSocket.setUid(Integer.parseInt(token));
                    break;
                default:
                    break;
            }
            tokenNo++;
        } while (tokenizer.hasMoreElements());
        return aSocket;
    }

    /**
     * IP アドレスの解析.
     * @param ipString 16進数文字列のIPアドレス
     * @return IPv4のIPアドレス
     */
    private static String convertIPtoString(final String ipString) {
        String s1 = "";
        if (ipString == null || ipString.length() < IP_HEX_LENGTH) {
            return s1;
        }
        int i = ipString.length();
        int j = 0;
        do {
            StringBuilder stringbuilder;
            String s2;
            stringbuilder = (new StringBuilder(String.valueOf(s1)))
                    .append(Integer.parseInt(ipString.substring(i - 2, i), HEX));
            if (j < IP_DECIMAL_LENGTH - 1) {
                s2 = ".";
            } else {
                s2 = "";
            }
            s1 = stringbuilder.append(s2).toString();
            i -= 2;
        } while (i >= 2 && ++j <= IP_DECIMAL_LENGTH);
        return s1;
    }

    /**
     * Socksocketの解析結果からアプリのパッケージ名を取得する.
     * @param context context
     * @param arrayList socketリスト
     */
    private static void processAppInfo(final Context context, final ArrayList<AndroidSocket> arrayList) {
        if (arrayList == null) {
            return;
        }
        for (AndroidSocket androidsocket : arrayList) {
            String[] as = context.getPackageManager().getPackagesForUid(androidsocket.getUid());
            if (as != null) {
                androidsocket.setAppName(as[0]);
            } else {
                androidsocket.setAppName("unknown");
            }
        }
    }
}