[CryptoGraph] 筆記 001

Commitment:
1. Hide
2. Binding

Verifiable Computation:
使用者用以確定Server運算是否正確
Authentication Computation
Server用來驗證使用者或使用者提出資料是否正確

[Java] javap 觀察看看

A.1 Examining Java Classfiles

已知Java會先編譯成class檔，

也就是Source Code編譯成Byte Code。

但是要看到Byte Code內的情況一般都會略過不談，

所以現在要用到只好很雞八的來看一下了。

而一般Java的JDC工具包內其實就已經有個工具可以用了，也就是 Javap。

javap -help  

Usage: javap <options> <classes>
where possible options include:

  -help                       顯示常用指令資訊
  -version                   顯示目前所用JDK版本編號
  -verbose / -v [檔名]  顯示[檔名]的所以class檔資訊
  -l                             顯示 line number 和 local variable tables 資訊

  -public                     顯示 public classes 和 members (其他皆不列出)
  -protected                顯示 protected/public classes 和 members
  -package                 顯示 package/protected/public classes 和 members (default)
  -p  -private                顯示  Show all classes and members

  -c                                   打開 class看ByteCode( Disassemble the code)
  -s                                    Print internal type signatures
  -sysinfo                           Show system info of class being processed
  -constants                       Show final constants
  -classpath <path>           Specify where to find user class files
  -cp <path>                       Specify where to find user class files
  -bootclasspath <path>    Override location of bootstrap class files

   -------------------------------------------------------------------------------------------------------------

public class A {   
    public static void main(String[] args){
        int a = 9;
        String c = "123";
    }   
   
    public void move(int a){}
   
    public boolean move2(){    return true;}
}

   -------------------------------------------------------------------------------------------------------------

-v A

Classfile /C:/Users/haha/Desktop/New folder/A.class
  Last modified 2016/2/19; size 377 bytes
  MD5 checksum 47008851a8f4aad1f298978ae5976262
  Compiled from "A.java"
public class A
  minor version: 0
  major version: 52
  flags: ACC_PUBLIC, ACC_SUPER
Constant pool:
   #1 = Methodref          #4.#17         // java/lang/Object."<init>":()V
   #2 = String             #18            // 123
   #3 = Class              #19            // A
   #4 = Class              #20            // java/lang/Object
   #5 = Utf8               <init>
   #6 = Utf8               ()V
   #7 = Utf8               Code
   #8 = Utf8               LineNumberTable
   #9 = Utf8               main
  #10 = Utf8               ([Ljava/lang/String;)V
  #11 = Utf8               move
  #12 = Utf8               (I)V
  #13 = Utf8               move2
  #14 = Utf8               ()Z
  #15 = Utf8               SourceFile
  #16 = Utf8               A.java
  #17 = NameAndType        #5:#6          // "<init>":()V
  #18 = Utf8               123
  #19 = Utf8               A
  #20 = Utf8               java/lang/Object
{
  public A();
    descriptor: ()V
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: aload_0
         1: invokespecial #1                  // Method java/lang/Object."<init>":()V
         4: return
      LineNumberTable:
        line 1: 0

  public static void main(java.lang.String[]);
    descriptor: ([Ljava/lang/String;)V
    flags: ACC_PUBLIC, ACC_STATIC
    Code:
      stack=1, locals=3, args_size=1
         0: bipush        9
         2: istore_1
         3: ldc           #2                  // String 123
         5: astore_2
         6: return
      LineNumberTable:
        line 3: 0
        line 4: 3
        line 5: 6

  public void move(int);
    descriptor: (I)V
    flags: ACC_PUBLIC
    Code:
      stack=0, locals=2, args_size=2
         0: return
      LineNumberTable:
        line 7: 0

  public boolean move2();
    descriptor: ()Z
    flags: ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
         0: iconst_1
         1: ireturn
      LineNumberTable:
        line 9: 0
}
SourceFile: "A.java"

   -------------------------------------------------------------------------------------------------------------

-l A

Compiled from "A.java"
public class A {
  public A();
    LineNumberTable:
      line 1: 0

  public static void main(java.lang.String[]);
    LineNumberTable:
      line 3: 0
      line 4: 3
      line 5: 6

  public void move(int);
    LineNumberTable:
      line 7: 0

  public boolean move2();
    LineNumberTable:
      line 9: 0
}

   -------------------------------------------------------------------------------------------------------------

-public A

Compiled from "A.java"
public class A {
  public A();
  public static void main(java.lang.String[]);
  public void move(int);
  public boolean move2();
}

   -------------------------------------------------------------------------------------------------------------

把 public void move(int); 改成 private void move(int);

-p A

Compiled from "A.java"
public class A {
  public A();
  public static void main(java.lang.String[]);
  private void move(int);
  public boolean move2();
}

   -------------------------------------------------------------------------------------------------------------

-c A

Compiled from "A.java"
public class A {
  public A();
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return

  public static void main(java.lang.String[]);
    Code:
       0: bipush        9
       2: istore_1
       3: ldc           #2                  // String 123
       5: astore_2
       6: return

  public boolean move2();
    Code:
       0: iconst_1
       1: ireturn
}

   -------------------------------------------------------------------------------------------------------------

-s A

Compiled from "A.java"
public class A {
  public A();
    descriptor: ()V

  public static void main(java.lang.String[]);
    descriptor: ([Ljava/lang/String;)V

  public boolean move2();
    descriptor: ()Z
}

   -------------------------------------------------------------------------------------------------------------

-sysinfo A

Classfile /C:/Users/haha/Desktop/New folder/A.class
  Last modified 2016/2/19; size 377 bytes
  MD5 checksum eaf868990ea17c4dd4ee7691a79c7cba
  Compiled from "A.java"
public class A {
  public A();
  public static void main(java.lang.String[]);
  public boolean move2();
}

 

 

ByteCod test ByteCodetest001

JAVA 是一個 type-safe language, 他的 field, local Variable, 和methods都會除存,
這稱呼為 Signatures.

而字串則會儲存在 constant pool中.

以下範例兩行敘述跟maia方法的回傳:

ByteCodetest001.java

class ByteCodetest001{
    public static void main(String args[]){
       
    }
}

用jd-gui-windows-1.4.0 的 Java Decompiler做反組譯:
ByteCodetest001.class

class ByteCodetest001
{
  public static void main(String[] paramArrayOfString) {}
}


用Sandmark 的 View JarFile 功能來看 ByteCodetest001.class ,
他的 Signatures, 也就是位於 [View] 中的 Method Sort 所顯示的像目,
會看到

ByteCode001
- <init>()V
- main([Ljava/lang/String;)V

Classes are internally represented by strings like "java/lang/string"
由文中敘述他將此稱為 Class 類,
兩行敘述比對一下

class ByteCodetest001{                        | <init>()V
public static void main(String args[]){     | main([Ljava/lang/String;)V


main([Ljava/lang/String;)V

main 表示此敘述為 main method
main([ 表示這是一個一為陣列 Arrays are denoted with a [ at the start of the signature.
main([L 表示 fully-qualified-class
main([Ljava/lang/String;) 我看來是main mothed 的輸入參數是一個string,
                                       而String 是一個位於lang類別抵下的參數, 就全不顯示上來了.

main([Ljava/lang/String;)V我看來是 is a void method on java.lang.Object.





 

javap ByteCodetest001 查看 bytecode

javap ByteCodetest001

Compiled from "ByteCodetest001.java"
class ByteCodetest001 {
  ByteCodetest001();
  public static void main(java.lang.String[]);
}

存成 bc檔
 -c ByteCodetest001 > ByteCodetest001.bc

Compiled from "ByteCodetest001.java"
class ByteCodetest001 {
  ByteCodetest001();
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return

  public static void main(java.lang.String[]);
    Code:
       0: return
}

在 Unbuntu 安裝 java 1.4

關網 http://www.oracle.com/technetwork/java/javasebusiness/downloads/java-archive-downloads-javase14-419411.html

 Java SE Development Kit 1.4.2_18 

Java SE Development Kit 1.4.2_18     (34.69 MB)      j2sdk-1_4_2_18-linux-i586.bin

之後安裝完後, 其實還會有問題.

因為是用 共用文件傳資料的, 所以路徑會比較不同

root@liu-VirtualBox:/media/sf_share_data/j2sdk1.4.2_18/bin# java
The program 'java' can be found in the following packages:
 * default-jre
 * gcj-4.8-jre-headless
 * openjdk-7-jre-headless
 * gcj-4.6-jre-headless
 * openjdk-6-jre-headless
Try: apt-get install <selected package>

依序執行指令, 就好了

root@liu-VirtualBox:/media/sf_share_data/j2sdk1.4.2_18/bin# sudo apt-get install defailt-jre
Reading package lists... Done
Building dependency tree      
Reading state information... Done
E: Unable to locate package defailt-jre

root@liu-VirtualBox:/media/sf_share_data# sudo apt-get install default
Reading package lists... Done
Building dependency tree      
Reading state information... Done
E: Unable to locate package default
root@liu-VirtualBox:/media/sf_share_data#

root@liu-VirtualBox:/media/sf_share_data# sudo apt-get install openjdk-7-jre

DONE

而刪除文件也要下載套件

remove data instance and process :
root@liu-VirtualBox:/media# redir test
The program 'redir' is currently not installed. You can install it by typing:
apt-get install redir
root@liu-VirtualBox:/media# sudo apt-get install redir
Reading package lists... Done
Building dependency tree      
Reading state information... Done
The following NEW packages will be installed:
  redir
0 upgraded, 1 newly installed, 0 to remove and 258 not upgraded.
Need to get 18.6 kB of archives.
After this operation, 71.7 kB of additional disk space will be used.
Get:1 http://tw.archive.ubuntu.com/ubuntu/ trusty/universe redir i386 2.2.1-11 [18.6 kB]
Fetched 18.6 kB in 0s (20.4 kB/s)
Selecting previously unselected package redir.
(Reading database ... 165089 files and directories currently installed.)
Preparing to unpack .../redir_2.2.1-11_i386.deb ...
Unpacking redir (2.2.1-11) ...
Processing triggers for man-db (2.6.7.1-1ubuntu1) ...
Setting up redir (2.2.1-11) ...

讓 USB 可以傳4G以上檔案

一般 USB 預設 File system 都是 FAT32,
所以使用前先格式化, 設定成 NTF就好了.

Let the Usb can be transfer a data bigger than the size of 4 G . 

[Unbuntu]Oracle VM Virtual Box 全螢幕

上方選像中先點選 [裝置] -> [插入 Guest Additions CD 映像]


就會出現 "VBOXADDITIONS_5.0.14_105127" contains software intended to be
automatically started. Would you like to run it?

If you don't trust this location or aren't sure, press Cancel.

[Cancel][Run]

再輸入密碼成位root安裝

就會出現另一個 Virtual Box Guest Additions installation





跑完之後,會有 return or close the window
又邊就會有一個光碟樣子的圖示,
就是安完成, 點下去後就會看到一推檔案.



往下移點選 VBoxWindowsAdditions-x86.exe [32位元]
點選 VBoxWindowsAdditions-amd-x64.exe [64位元]

因為他的位置在 Device 在用終端機的時候要調一下路徑,
也可以直接拉到終端機,
sudo /media/liu/VBOXADDITIONS_5.0.14_105127/VBoxWindowsAdditions-x86 run
因為sudo 會要求再輸入一次密碼.

有沒有裝好, 重新開一次 unbumtu 就知道了 .