Jesal submission of Blockchain

assignments/Jesal/Block.cpp

@@ -0,0 +1,39 @@
+#include "Block.h"
+#include "sha256.h"
+
+Block::Block(uint32_t nIndexIn, const string &sDataIn) : _nIndex(nIndexIn), _sData(sDataIn)
+{
+    _nNonce = 0;
+    _tTime = time(nullptr);
+
+    sHash = _CalculateHash();
+}
+
+void Block::MineBlock(uint32_t nDifficulty)
+{
+    char cstr[nDifficulty + 1];
+    for (uint32_t i = 0; i < nDifficulty; ++i)
+    {
+        cstr[i] = '0';
+    }
+    cstr[nDifficulty] = '\0';
+
+    string str(cstr);
+
+    do
+    {
+        _nNonce++;
+        sHash = _CalculateHash();
+    }
+    while (sHash.substr(0, nDifficulty) != str);
+
+    cout << "Block mined: " << sHash << endl;
+}
+
+inline string Block::_CalculateHash() const
+{
+    stringstream ss;
+    ss << _nIndex << sPrevHash << _tTime << _sData << _nNonce;
+
+    return sha256(ss.str());
+}

assignments/Jesal/Block.h

@@ -0,0 +1,28 @@
+#ifndef TESTCHAIN_BLOCK_H
+#define TESTCHAIN_BLOCK_H
+
+#include <cstdint>
+#include <iostream>
+#include <sstream>
+
+using namespace std;
+
+class Block {
+public:
+    string sHash;
+    string sPrevHash;
+
+    Block(uint32_t nIndexIn, const string &sDataIn);
+
+    void MineBlock(uint32_t nDifficulty);
+
+private:
+    uint32_t _nIndex;
+    uint32_t _nNonce;
+    string _sData;
+    time_t _tTime;
+
+    string _CalculateHash() const;
+};
+
+#endif

assignments/Jesal/Blockchain.cpp

@@ -0,0 +1,19 @@
+#include "Blockchain.h"
+
+Blockchain::Blockchain()
+{
+    _vChain.emplace_back(Block(0, "Genesis Block"));
+    _nDifficulty = 6;
+}
+
+void Blockchain::AddBlock(Block bNew)
+{
+    bNew.sPrevHash = _GetLastBlock().sHash;
+    bNew.MineBlock(_nDifficulty);
+    _vChain.push_back(bNew);
+}
+
+Block Blockchain::_GetLastBlock() const
+{
+    return _vChain.back();
+}

assignments/Jesal/Blockchain.h

@@ -0,0 +1,23 @@
+#ifndef TESTCHAIN_BLOCKCHAIN_H
+#define TESTCHAIN_BLOCKCHAIN_H
+
+#include <cstdint>
+#include <vector>
+#include "Block.h"
+
+using namespace std;
+
+class Blockchain {
+public:
+    Blockchain();
+
+    void AddBlock(Block bNew);
+
+private:
+    uint32_t _nDifficulty;
+    vector<Block> _vChain;
+
+    Block _GetLastBlock() const;
+};
+
+#endif

assignments/Jesal/README.md

@@ -0,0 +1,18 @@
+*** Project Title ***
+"Blockchain In C++"
+
+*************************
+
+*** Use Linux version 22.04 ***
+
+*************************
+
+**** To Compile the Code ****
+
+g++ -lstdc++ -o Jesal main.cpp Block.cpp Blockchain.cpp sha256.cpp
+
+*************************
+
+**** To run the Code ****
+
+./Jesal

assignments/Jesal/main.cpp

@@ -0,0 +1,17 @@
+#include "Blockchain.h"
+
+int main()
+{
+    Blockchain bChain = Blockchain();
+
+    cout << "Mining block 1..." << endl;
+    bChain.AddBlock(Block(1, "Block 1 Data"));
+
+    cout << "Mining block 2..." << endl;
+    bChain.AddBlock(Block(2, "Block 2 Data"));
+
+    cout << "Mining block 3..." << endl;
+    bChain.AddBlock(Block(3, "Block 3 Data"));
+
+    return 0;
+}

assignments/Jesal/sha256-LICENSE.txt

@@ -0,0 +1,36 @@
+/*
+ * Updated to C++, zedwood.com 2012
+ * Based on Olivier Gay's version
+ * See Modified BSD License below:
+ *
+ * FIPS 180-2 SHA-224/256/384/512 implementation
+ * Issue date:  04/30/2005
+ * http://www.ouah.org/ogay/sha2/
+ *
+ * Copyright (C) 2005, 2007 Olivier Gay <[email protected]>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */

assignments/Jesal/sha256.cpp

@@ -0,0 +1,132 @@
+#include <cstring>
+#include <fstream>
+#include "sha256.h"
+
+const unsigned int SHA256::sha256_k[64] = //UL = uint32
+        {0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
+         0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
+         0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
+         0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
+         0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
+         0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
+         0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
+         0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
+         0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
+         0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
+         0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
+         0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
+         0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
+         0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
+         0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
+         0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2};
+
+void SHA256::transform(const unsigned char *message, unsigned int block_nb)
+{
+    uint32 w[64];
+    uint32 wv[8];
+    uint32 t1, t2;
+    const unsigned char *sub_block;
+    int i;
+    int j;
+    for (i = 0; i < (int) block_nb; i++) {
+        sub_block = message + (i << 6);
+        for (j = 0; j < 16; j++) {
+            SHA2_PACK32(&sub_block[j << 2], &w[j]);
+        }
+        for (j = 16; j < 64; j++) {
+            w[j] =  SHA256_F4(w[j -  2]) + w[j -  7] + SHA256_F3(w[j - 15]) + w[j - 16];
+        }
+        for (j = 0; j < 8; j++) {
+            wv[j] = m_h[j];
+        }
+        for (j = 0; j < 64; j++) {
+            t1 = wv[7] + SHA256_F2(wv[4]) + SHA2_CH(wv[4], wv[5], wv[6])
+                 + sha256_k[j] + w[j];
+            t2 = SHA256_F1(wv[0]) + SHA2_MAJ(wv[0], wv[1], wv[2]);
+            wv[7] = wv[6];
+            wv[6] = wv[5];
+            wv[5] = wv[4];
+            wv[4] = wv[3] + t1;
+            wv[3] = wv[2];
+            wv[2] = wv[1];
+            wv[1] = wv[0];
+            wv[0] = t1 + t2;
+        }
+        for (j = 0; j < 8; j++) {
+            m_h[j] += wv[j];
+        }
+    }
+}
+
+void SHA256::init()
+{
+    m_h[0] = 0x6a09e667;
+    m_h[1] = 0xbb67ae85;
+    m_h[2] = 0x3c6ef372;
+    m_h[3] = 0xa54ff53a;
+    m_h[4] = 0x510e527f;
+    m_h[5] = 0x9b05688c;
+    m_h[6] = 0x1f83d9ab;
+    m_h[7] = 0x5be0cd19;
+    m_len = 0;
+    m_tot_len = 0;
+}
+
+void SHA256::update(const unsigned char *message, unsigned int len)
+{
+    unsigned int block_nb;
+    unsigned int new_len, rem_len, tmp_len;
+    const unsigned char *shifted_message;
+    tmp_len = SHA224_256_BLOCK_SIZE - m_len;
+    rem_len = len < tmp_len ? len : tmp_len;
+    memcpy(&m_block[m_len], message, rem_len);
+    if (m_len + len < SHA224_256_BLOCK_SIZE) {
+        m_len += len;
+        return;
+    }
+    new_len = len - rem_len;
+    block_nb = new_len / SHA224_256_BLOCK_SIZE;
+    shifted_message = message + rem_len;
+    transform(m_block, 1);
+    transform(shifted_message, block_nb);
+    rem_len = new_len % SHA224_256_BLOCK_SIZE;
+    memcpy(m_block, &shifted_message[block_nb << 6], rem_len);
+    m_len = rem_len;
+    m_tot_len += (block_nb + 1) << 6;
+}
+
+void SHA256::final(unsigned char *digest)
+{
+    unsigned int block_nb;
+    unsigned int pm_len;
+    unsigned int len_b;
+    int i;
+    block_nb = (1 + ((SHA224_256_BLOCK_SIZE - 9)
+                     < (m_len % SHA224_256_BLOCK_SIZE)));
+    len_b = (m_tot_len + m_len) << 3;
+    pm_len = block_nb << 6;
+    memset(m_block + m_len, 0, pm_len - m_len);
+    m_block[m_len] = 0x80;
+    SHA2_UNPACK32(len_b, m_block + pm_len - 4);
+    transform(m_block, block_nb);
+    for (i = 0 ; i < 8; i++) {
+        SHA2_UNPACK32(m_h[i], &digest[i << 2]);
+    }
+}
+
+std::string sha256(std::string input)
+{
+    unsigned char digest[SHA256::DIGEST_SIZE];
+    memset(digest,0,SHA256::DIGEST_SIZE);
+
+    SHA256 ctx = SHA256();
+    ctx.init();
+    ctx.update( (unsigned char*)input.c_str(), input.length());
+    ctx.final(digest);
+
+    char buf[2*SHA256::DIGEST_SIZE+1];
+    buf[2*SHA256::DIGEST_SIZE] = 0;
+    for (int i = 0; i < SHA256::DIGEST_SIZE; i++)
+        sprintf(buf+i*2, "%02x", digest[i]);
+    return std::string(buf);
+}

assignments/Jesal/sha256.h

@@ -0,0 +1,53 @@
+#ifndef SHA256_H
+#define SHA256_H
+#include <string>
+
+class SHA256
+{
+protected:
+    typedef unsigned char uint8;
+    typedef unsigned int uint32;
+    typedef unsigned long long uint64;
+
+    const static uint32 sha256_k[];
+    static const unsigned int SHA224_256_BLOCK_SIZE = (512/8);
+public:
+    void init();
+    void update(const unsigned char *message, unsigned int len);
+    void final(unsigned char *digest);
+    static const unsigned int DIGEST_SIZE = ( 256 / 8);
+
+protected:
+    void transform(const unsigned char *message, unsigned int block_nb);
+    unsigned int m_tot_len;
+    unsigned int m_len;
+    unsigned char m_block[2*SHA224_256_BLOCK_SIZE];
+    uint32 m_h[8];
+};
+
+std::string sha256(std::string input);
+
+#define SHA2_SHFR(x, n)    (x >> n)
+#define SHA2_ROTR(x, n)   ((x >> n) | (x << ((sizeof(x) << 3) - n)))
+#define SHA2_ROTL(x, n)   ((x << n) | (x >> ((sizeof(x) << 3) - n)))
+#define SHA2_CH(x, y, z)  ((x & y) ^ (~x & z))
+#define SHA2_MAJ(x, y, z) ((x & y) ^ (x & z) ^ (y & z))
+#define SHA256_F1(x) (SHA2_ROTR(x,  2) ^ SHA2_ROTR(x, 13) ^ SHA2_ROTR(x, 22))
+#define SHA256_F2(x) (SHA2_ROTR(x,  6) ^ SHA2_ROTR(x, 11) ^ SHA2_ROTR(x, 25))
+#define SHA256_F3(x) (SHA2_ROTR(x,  7) ^ SHA2_ROTR(x, 18) ^ SHA2_SHFR(x,  3))
+#define SHA256_F4(x) (SHA2_ROTR(x, 17) ^ SHA2_ROTR(x, 19) ^ SHA2_SHFR(x, 10))
+#define SHA2_UNPACK32(x, str)                 \
+{                                             \
+    *((str) + 3) = (uint8) ((x)      );       \
+    *((str) + 2) = (uint8) ((x) >>  8);       \
+    *((str) + 1) = (uint8) ((x) >> 16);       \
+    *((str) + 0) = (uint8) ((x) >> 24);       \
+}
+#define SHA2_PACK32(str, x)                   \
+{                                             \
+    *(x) =   ((uint32) *((str) + 3)      )    \
+           | ((uint32) *((str) + 2) <<  8)    \
+           | ((uint32) *((str) + 1) << 16)    \
+           | ((uint32) *((str) + 0) << 24);   \
+}
+#endif