区块链模型原理入门学习2——细化模型

  以上描述中，存在一些非生产情景的理想化设定。

  比如：

　　1.没有设计谜题难度平衡

　　2.没有加入加密校验数字签证

　　3.没有设计个人钱包

　　4.广播问题

　　......

 

  代码：

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
/*
    ZY的区块链简易模型学习
    1.1 搭建基础模型（添加数据块、校验数据块）
    1.2 加入挖矿机制
    1.3 加入挖矿奖励机制
 */
namespace TestPrj
{
    class Program
    {
        static void Main(string[] args)
        {
            Chain chain = new Chain();

            //1.3 到现在 就不能直接生成块了，而是通过矿工领取待验证块进行计算后验证合法后才能链入区块链上
            /*            Block block1 = new Block("转账10元");
                        chain.AddNewBlock(block1);
                        Block block2 = new Block("转账30元");
                        chain.AddNewBlock(block2);*/

            //1.3 模拟产生两条转账记录
            var transaction1 = new Transaction("address1", "address2", "30");
            var transaction2 = new Transaction("address1", "address2", "15");

            //1.3 把转账记录加入到转账记录池中
            chain.AddTransactionToPool(transaction1);
            chain.AddTransactionToPool(transaction2);

            //1.3 模拟矿工挖矿
            chain.MineAndReward("addressminer");

            //查看当前数据链总共数据快数
            chain.ViewBlockCount();

            //查看所有数据链
            chain.ViewAllBlocks();

            //验证数据链
            Console.WriteLine(chain.Validate());

            //模拟篡改数据
            chain.Blocks[1].Data = "转账100元";

            //验证数据链
            Console.WriteLine(chain.Validate());
        }
    }
}

//数据块
public class Block
{
    /*    //数据
        private string data;*/
    //1.3 这里的data 因为存储的是转账记录 所以类型为object
    private object data;

    //前一个Block的hash
    private string prehash;
    //当前Block的hash
    private string curhash;
    private string count;
    //1.3 确认时间
    private DateTime time;
    public Block(object data)
    {
        this.prehash = "";
        this.data = data;
        this.curhash = "";
        this.count = "";
    }

    //注意:这里为了模拟篡改数据专门封装的字段
    public object Data { get => data; set => data = value; }
    public string Prehash { get => prehash; set => prehash = value; }
    public string Curhash { get => curhash; set => curhash = value; }
    public string Count { get => count; set => count = value; }
    public DateTime Time { get => time; set => time = value; }

    //计算当前Block的Hash
    /*    public string ComputeHash(string prehash)
        {
            this.prehash = prehash;
            return SHA256(this.data + this.prehash);
        }*/

    //1.2 计算当前Block符合要求的Hash
    public string ComputeBlockPassHash(string prehash, string str = "")
    {
        this.prehash = prehash;
        //return SHA256(this.data + this.prehash + str);
        //1.3 这里需要返回的数据
        //更新时间
        //[转账记录].jsonString+prehash+str
        this.Time = DateTimeOffset.UtcNow.DateTime;
        return SHA256(JsonConvert.SerializeObject(this.data) + prehash + str);
    }

    //Hash256计算
    public string SHA256(string str)
    {
        //如果str有中文，不同Encoding的sha是不同的！！
        byte[] SHA256Data = Encoding.UTF8.GetBytes(str);

        SHA256Managed Sha256 = new SHA256Managed();
        byte[] by = Sha256.ComputeHash(SHA256Data);

        return BitConverter.ToString(by).Replace("-", "").ToLower();
    }

    //显示Block数据
    public void ViewInfo()
    {
        Console.WriteLine("====");
        Console.WriteLine("[prehash]->" + this.prehash);
        Console.WriteLine("[data]->");
        if (this.data != null)
        {
            foreach (var item in (List<Transaction>)this.data)
            {
                Console.WriteLine(item.ToString());
            }
        }
        Console.WriteLine("[time]->" + this.time.ToLocalTime());
        Console.WriteLine("[hash]->" + this.curhash);
    }
}

public class Chain
{
    private List<Block> blocks;

    //1.3 转账记录池，用处存储每一笔转账记录
    private List<Transaction> transactionPool;

    //1.3 奖励金
    private string reward = "50";

    //1.3 困难度
    private int difficulty = 2;
    public List<Block> Blocks { get => blocks; set => blocks = value; }

    public Chain()
    {
        this.blocks = new List<Block>();
        this.transactionPool = new List<Transaction>();
        Block genesisBloc = new Block(null);
        genesisBloc.Curhash = genesisBloc.ComputeBlockPassHash("genesis");
        AddNewBlock(genesisBloc);
    }

    public void ViewBlockCount()
    {
        Console.WriteLine("当前数据块总数->" + this.blocks.Count);
    }

    //添加Block
    public void AddNewBlock(Block newblock)
    {
        //空链的情况
        if (this.blocks.Count == 0)
        {
            this.blocks.Add(newblock);
            newblock.Curhash = newblock.ComputeBlockPassHash(newblock.Prehash);
            return;
        }
        /*链接新Block*/
        //新的Block的prehash是上一个block的curhash
        newblock.Prehash = this.blocks[this.blocks.Count - 1].Curhash;

        //1.2 加入挖矿计算后，需要符合要求的Hash才能被链入，其中会涉及平均计算时间和设置计算困难度的关系（这里暂时不考虑）
        //newblock.Curhash = newblock.ComputeHash(newblock.Prehash);

        /*1.2挖矿计算*/
        ComputePassHash(newblock, this.difficulty);

        /*添加新Block*/
        this.blocks.Add(newblock);
    }

    //1.2 获取计算难度
    public string GetComputeDifficulty(int difficulty)
    {
        //这里做简单要求，即根据难度，形成指定数量的0的字符串
        string passStr = "";
        for (int setDiffIndex = 0; setDiffIndex < difficulty; setDiffIndex++)
        {
            passStr += "0";
        }
        return passStr;
    }

    //1.2 计算符合要求的哈希值
    public void ComputePassHash(Block block, int difficulty)
    {
        int count = 0;
        while (true)
        {
            count++;
            //加入参数计算哈希值
            string checkHash = block.ComputeBlockPassHash(block.Prehash, count.ToString());
            Console.WriteLine("第 " + count + "次计算->" + checkHash);
            //判断计算的哈希值符合相应难度的要求，即前哈希值前四位必须为0才算合格
            if (checkHash.Substring(0, difficulty).Equals(GetComputeDifficulty(difficulty)))
            {
                block.Curhash = checkHash;
                block.Count = count.ToString();
                break;
            }
        }
        //模拟挖掘到符合的哈希值
        Console.WriteLine("经过" + count + "次计算挖掘到->" + block.Curhash);

        //1.3清空转账记录池
        //这里屏蔽掉的原因：因为本次学习取到了转账记录池里的全部记录的缘故，清理后会影响后面的显示，好吧..我承认，这就是个小BUG...
        //this.transactionPool.Clear();
    }

    //查看所有Block
    public void ViewAllBlocks()
    {
        foreach (var item in this.blocks)
        {
            item.ViewInfo();
        }
    }

    //验证Chain
    public bool Validate()
    {
        //无任何数据块的情况
        if (this.blocks.Count == 0)
        {
            Console.WriteLine("[数据链异常]->数据链为空！");
            return false;
        }
        //只有源数据块的情况
        else if (this.blocks.Count == 1)
        {
            Console.WriteLine("验证完毕！");
            return true;
        }

        //遍历校验标志
        bool checkBlockSign = true;

        //遍历检查数据块，因为不检查源数据块，下标从1开始
        for (int checkBlockIndex = 1; checkBlockIndex < this.blocks.Count; checkBlockIndex++)
        {
            //检验curhash
            var checkBlock = this.blocks[checkBlockIndex];
            if (checkBlock.Curhash != checkBlock.ComputeBlockPassHash(checkBlock.Prehash, checkBlock.Count))
            {
                Console.WriteLine("[数据被篡改]->" + checkBlockIndex);
                checkBlockSign = false;
                break;
            }
            /*            //验证prehash
                        if (checkBlock.Prehash != this.blocks[checkBlockIndex - 1].Curhash)
                        {
                            Console.WriteLine("[数据链断裂]->" + checkBlockIndex);
                            checkBlockSign = false;
                            break;
                        }*/
        }
        Console.WriteLine("验证完毕！");
        return checkBlockSign;
    }

    //1.3 添加转账记录
    public void AddTransactionToPool(Transaction transaction)
    {
        this.transactionPool.Add(transaction);
    }

    //1.3挖矿并获取奖励
    public void MineAndReward(string minerAddress)
    {
        //生成奖励转账 因为系统奖励，所以转账人地址是空的
        var rewardTransform = new Transaction("", minerAddress, this.reward);

        //把矿工的奖励转账记录也要存进转账池子里
        this.transactionPool.Add(rewardTransform);

        //生成block（这里默认h获取转账池里的所有转账记录）
        var block = new Block(this.transactionPool);

        //计算合法哈希值
        AddNewBlock(block);
    }
}

//1.3交易记录 转账人 收款人 转账数额 （注意！这里没有转账时间，根据中本聪的论文，转账时间和block生成的时间是统一的，也就是说block被挖到的时候才会创建时间）
public class Transaction
{
    //转账方地址
    public string transferor;
    //收款方地址
    public string payee;
    //转账金额
    public string money;

    public Transaction(string transferor, string payee, string money)
    {
        this.transferor = transferor;
        this.payee = payee;
        this.money = money;
    }
    public override string ToString()
    {
        return this.transferor + "-" + this.payee + "-" + this.money;
    }
}

 

  执行结果：

  到此，奖励机制加入完成了，当然，还有很多地方需要优化和改进。

 【学习是人类进步的阶梯】