密码认证-SHA加盐密码

2022-02-23 22:32:56 阅读：288 来源： 互联网

标签：const SHA int unsigned char 密码加盐 sha256 uint32

密码认证，首先是密码加密算法，然后密码咋存储，如图所示

密码加密分为不可加密和可逆加密算法。安全存储策略，有明文保存和加盐保存，明文保持容易导致密码丢失，一般采用加盐密码保持。注册和认证流程如下：

用户注册一个帐号
密码经过哈希加密储存在数据库中。只要密码被写入磁盘，任何时候都不允许是明文
当用户登录的时候，从数据库取出已经加密的密码，和经过哈希的用户输入进行对比
如果哈希值相同，用户获得登入授权，否则，会被告知输入了无效的登录信息
每当有用户尝试登录，以上两步都会重复

加密过程采用sha256加盐保存：（参考C++ sha256 function :: zedwood.com）

sha256.h:

#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

sha256.cpp:

#define  _CRT_SECURE_NO_WARNINGS
#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);
}

主文件：

/*
http://www.zedwood.com/article/cpp-sha256-function
*/
#include <iostream>
#include "sha256.h"

using std::string;
using std::cout;
using std::endl;

int main(int argc, char* argv[])
{
    string input = "grape";
    string output1 = sha256(input);
    cout << "sha256('" << input << "'):" << output1 << endl;

    string output2 = input;
    for (int index = 0; index < 10; index++)
    {
        output2 = sha256(sha256(output2) + "111");
    }
    
    cout << "sha256('" << input << "'):" << output2 << endl;

    return 0;
}

参考：

(241条消息) 加盐密码哈希：如何正确使用_Code-lover's Learning Notes-CSDN博客

(241条消息) 现行安全存储策略-密码加盐_weixin_41508948的博客-CSDN博客

(241条消息) 可逆加密和不可逆加密_haohaoxuexiyai的博客-CSDN博客_可逆加密

标签：const,SHA,int,unsigned,char,密码,加盐,sha256,uint32
来源： https://blog.csdn.net/weixin_39752599/article/details/123100673

本站声明： 1. iCode9 技术分享网（下文简称本站）提供的所有内容，仅供技术学习、探讨和分享；
2. 关于本站的所有留言、评论、转载及引用，纯属内容发起人的个人观点，与本站观点和立场无关；
3. 关于本站的所有言论和文字，纯属内容发起人的个人观点，与本站观点和立场无关；
4. 本站文章均是网友提供，不完全保证技术分享内容的完整性、准确性、时效性、风险性和版权归属；如您发现该文章侵犯了您的权益，可联系我们第一时间进行删除；
5. 本站为非盈利性的个人网站，所有内容不会用来进行牟利，也不会利用任何形式的广告来间接获益，纯粹是为了广大技术爱好者提供技术内容和技术思想的分享性交流网站。

ICode9

密码认证-SHA加盐密码