ICode9

精准搜索请尝试: 精确搜索
首页 > 编程语言> 文章详细

md5信息摘要算法 基于16位机器运行

2020-07-02 12:06:32  阅读:268  来源: 互联网

标签:16 void unsigned long char 机器运行 context input md5


MD5信息摘要算法(Message Digest Algorithm)

  1. md5是一种密码散列函数,可以生成128位(16字节)的散列值,用于确保信息传输完整一致。
  2. 这里举例如何在16机器上实现md5算法:
  3. md5.h 
     1 #ifndef MD5_H
     2 #define MD5_H
     3  
     4 typedef struct
     5 {
     6     unsigned long count[2];
     7     unsigned long state[4];
     8     unsigned char buffer[64];   
     9 }MD5_CTX;
    10  
    11                          
    12 #define F(x,y,z) ((x & y) | (~x & z))
    13 #define G(x,y,z) ((x & z) | (y & ~z))
    14 #define H(x,y,z) (x^y^z)
    15 #define I(x,y,z) (y ^ (x | ~z))
    16 #define ROTATE_LEFT(x,n) ((x << n) | (x >> (32-n)))
    17 #define FF(a,b,c,d,x,s,ac) \
    18           { \
    19           a += F(b,c,d) + x + ac; \
    20           a = ROTATE_LEFT(a,s); \
    21           a += b; \
    22           }
    23 #define GG(a,b,c,d,x,s,ac) \
    24           { \
    25           a += G(b,c,d) + x + ac; \
    26           a = ROTATE_LEFT(a,s); \
    27           a += b; \
    28           }
    29 #define HH(a,b,c,d,x,s,ac) \
    30           { \
    31           a += H(b,c,d) + x + ac; \
    32           a = ROTATE_LEFT(a,s); \
    33           a += b; \
    34           }
    35 #define II(a,b,c,d,x,s,ac) \
    36           { \
    37           a += I(b,c,d) + x + ac; \
    38           a = ROTATE_LEFT(a,s); \
    39           a += b; \
    40           }                                            
    41 void MD5Init(MD5_CTX *context);
    42 void MD5Update(MD5_CTX *context,unsigned char *input,unsigned long inputlen);
    43 void MD5Final(MD5_CTX *context,unsigned char digest[16]);
    44 void MD5Transform(unsigned long state[4],unsigned char block[64]);
    45 void MD5Encode(unsigned char *output,unsigned long *input,unsigned long len);
    46 void MD5Decode(unsigned long *output,unsigned char *input,unsigned long len);
    47 void md5_test(void);
    48 
    49 #endif
    50 
    51 //================ end of file =====================
    md5.h

     

  4.   1 #include <string.h>
      2 #include <stdio.h>
      3 #include <math.h>
      4 #include <stdlib.h>
      5 #include <float.h>
      6 #include <limits.h>
      7 #include <ctype.h>
      8 #include "md5.h"
      9  
     10 unsigned char PADDING[]={0x80,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
     11                          0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
     12                          0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
     13                          0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
     14                          
     15 void MD5Init(MD5_CTX *context)
     16 {
     17      context->count[0] = 0;
     18      context->count[1] = 0;
     19      context->state[0] = 0x67452301;
     20      context->state[1] = 0xEFCDAB89;
     21      context->state[2] = 0x98BADCFE;
     22      context->state[3] = 0x10325476;
     23 }
     24 void MD5Update(MD5_CTX *context,unsigned char *input,unsigned long inputlen)
     25 {
     26     unsigned long i = 0,index = 0,partlen = 0;
     27     index = (context->count[0] >> 3) & 0x3F;
     28     partlen = 64 - index;
     29     context->count[0] += inputlen << 3;
     30     if(context->count[0] < (inputlen << 3))
     31        context->count[1]++;
     32     context->count[1] += inputlen >> 29;
     33     
     34     if(inputlen >= partlen)
     35     {
     36        memcpy(&context->buffer[index],input,partlen);
     37        MD5Transform(context->state,context->buffer);
     38        for(i = partlen;i+64 <= inputlen;i+=64)
     39            MD5Transform(context->state,&input[i]);
     40        index = 0;        
     41     }  
     42     else
     43     {
     44         i = 0;
     45     }
     46     memcpy(&context->buffer[index],&input[i],inputlen-i);
     47 }
     48 void MD5Final(MD5_CTX *context,unsigned char digest[16])
     49 {
     50     unsigned long index = 0,padlen = 0;
     51     unsigned char bits[8];
     52     index = (context->count[0] >> 3) & 0x3F;
     53     padlen = (index < 56)?(56-index):(120-index);
     54     MD5Encode(bits,context->count,8);
     55     MD5Update(context,PADDING,padlen);
     56     MD5Update(context,bits,8);
     57     MD5Encode(digest,context->state,16);
     58 }
     59 void MD5Encode(unsigned char *output,unsigned long *input,unsigned long len)
     60 {
     61     unsigned long i = 0,j = 0;
     62     while(j < len)
     63     {
     64          output[j] = input[i] & 0xFF;  
     65          output[j+1] = (input[i] >> 8) & 0xFF;
     66          output[j+2] = (input[i] >> 16) & 0xFF;
     67          output[j+3] = (input[i] >> 24) & 0xFF;
     68          i++;
     69          j+=4;
     70     }
     71 }
     72 void MD5Decode(unsigned long *output,unsigned char *input,unsigned long len)
     73 {
     74      unsigned long i = 0,j = 0;
     75      while(j < len)
     76      {
     77            output[i] = (input[j]) |
     78                        ((unsigned long)input[j+1] << 8) |
     79                        ((unsigned long)input[j+2] << 16) |
     80                        ((unsigned long)input[j+3] << 24);
     81            i++;
     82            j+=4; 
     83      }
     84 }
     85 void MD5Transform(unsigned long state[4],unsigned char block[64])
     86 {
     87   unsigned long a = state[0];
     88   unsigned long b = state[1];
     89   unsigned long c = state[2];
     90   unsigned long d = state[3];
     91   unsigned long x[64];
     92   MD5Decode(x,block,64);
     93   FF(a, b, c, d, x[ 0], 7, 0xd76aa478); /* 1 */
     94   FF(d, a, b, c, x[ 1], 12, 0xe8c7b756); /* 2 */
     95   FF(c, d, a, b, x[ 2], 17, 0x242070db); /* 3 */
     96   FF(b, c, d, a, x[ 3], 22, 0xc1bdceee); /* 4 */
     97   FF(a, b, c, d, x[ 4], 7, 0xf57c0faf); /* 5 */
     98   FF(d, a, b, c, x[ 5], 12, 0x4787c62a); /* 6 */
     99   FF(c, d, a, b, x[ 6], 17, 0xa8304613); /* 7 */
    100   FF(b, c, d, a, x[ 7], 22, 0xfd469501); /* 8 */
    101   FF(a, b, c, d, x[ 8], 7, 0x698098d8); /* 9 */
    102   FF(d, a, b, c, x[ 9], 12, 0x8b44f7af); /* 10 */
    103   FF(c, d, a, b, x[10], 17, 0xffff5bb1); /* 11 */
    104   FF(b, c, d, a, x[11], 22, 0x895cd7be); /* 12 */
    105   FF(a, b, c, d, x[12], 7, 0x6b901122); /* 13 */
    106   FF(d, a, b, c, x[13], 12, 0xfd987193); /* 14 */
    107   FF(c, d, a, b, x[14], 17, 0xa679438e); /* 15 */
    108   FF(b, c, d, a, x[15], 22, 0x49b40821); /* 16 */
    109  
    110   /* Round 2 */
    111   GG(a, b, c, d, x[ 1], 5, 0xf61e2562); /* 17 */
    112   GG(d, a, b, c, x[ 6], 9, 0xc040b340); /* 18 */
    113   GG(c, d, a, b, x[11], 14, 0x265e5a51); /* 19 */
    114   GG(b, c, d, a, x[ 0], 20, 0xe9b6c7aa); /* 20 */
    115   GG(a, b, c, d, x[ 5], 5, 0xd62f105d); /* 21 */
    116   GG(d, a, b, c, x[10], 9,  0x2441453); /* 22 */
    117   GG(c, d, a, b, x[15], 14, 0xd8a1e681); /* 23 */
    118   GG(b, c, d, a, x[ 4], 20, 0xe7d3fbc8); /* 24 */
    119   GG(a, b, c, d, x[ 9], 5, 0x21e1cde6); /* 25 */
    120   GG(d, a, b, c, x[14], 9, 0xc33707d6); /* 26 */
    121   GG(c, d, a, b, x[ 3], 14, 0xf4d50d87); /* 27 */
    122   GG(b, c, d, a, x[ 8], 20, 0x455a14ed); /* 28 */
    123   GG(a, b, c, d, x[13], 5, 0xa9e3e905); /* 29 */
    124   GG(d, a, b, c, x[ 2], 9, 0xfcefa3f8); /* 30 */
    125   GG(c, d, a, b, x[ 7], 14, 0x676f02d9); /* 31 */
    126   GG(b, c, d, a, x[12], 20, 0x8d2a4c8a); /* 32 */
    127  
    128   /* Round 3 */
    129   HH(a, b, c, d, x[ 5], 4, 0xfffa3942); /* 33 */
    130   HH(d, a, b, c, x[ 8], 11, 0x8771f681); /* 34 */
    131   HH(c, d, a, b, x[11], 16, 0x6d9d6122); /* 35 */
    132   HH(b, c, d, a, x[14], 23, 0xfde5380c); /* 36 */
    133   HH(a, b, c, d, x[ 1], 4, 0xa4beea44); /* 37 */
    134   HH(d, a, b, c, x[ 4], 11, 0x4bdecfa9); /* 38 */
    135   HH(c, d, a, b, x[ 7], 16, 0xf6bb4b60); /* 39 */
    136   HH(b, c, d, a, x[10], 23, 0xbebfbc70); /* 40 */
    137   HH(a, b, c, d, x[13], 4, 0x289b7ec6); /* 41 */
    138   HH(d, a, b, c, x[ 0], 11, 0xeaa127fa); /* 42 */
    139   HH(c, d, a, b, x[ 3], 16, 0xd4ef3085); /* 43 */
    140   HH(b, c, d, a, x[ 6], 23,  0x4881d05); /* 44 */
    141   HH(a, b, c, d, x[ 9], 4, 0xd9d4d039); /* 45 */
    142   HH(d, a, b, c, x[12], 11, 0xe6db99e5); /* 46 */
    143   HH(c, d, a, b, x[15], 16, 0x1fa27cf8); /* 47 */
    144   HH(b, c, d, a, x[ 2], 23, 0xc4ac5665); /* 48 */
    145  
    146   /* Round 4 */
    147   II(a, b, c, d, x[ 0], 6, 0xf4292244); /* 49 */
    148   II(d, a, b, c, x[ 7], 10, 0x432aff97); /* 50 */
    149   II(c, d, a, b, x[14], 15, 0xab9423a7); /* 51 */
    150   II(b, c, d, a, x[ 5], 21, 0xfc93a039); /* 52 */
    151   II(a, b, c, d, x[12], 6, 0x655b59c3); /* 53 */
    152   II(d, a, b, c, x[ 3], 10, 0x8f0ccc92); /* 54 */
    153   II(c, d, a, b, x[10], 15, 0xffeff47d); /* 55 */
    154   II(b, c, d, a, x[ 1], 21, 0x85845dd1); /* 56 */
    155   II(a, b, c, d, x[ 8], 6, 0x6fa87e4f); /* 57 */
    156   II(d, a, b, c, x[15], 10, 0xfe2ce6e0); /* 58 */
    157   II(c, d, a, b, x[ 6], 15, 0xa3014314); /* 59 */
    158   II(b, c, d, a, x[13], 21, 0x4e0811a1); /* 60 */
    159   II(a, b, c, d, x[ 4], 6, 0xf7537e82); /* 61 */
    160   II(d, a, b, c, x[11], 10, 0xbd3af235); /* 62 */
    161   II(c, d, a, b, x[ 2], 15, 0x2ad7d2bb); /* 63 */
    162   II(b, c, d, a, x[ 9], 21, 0xeb86d391); /* 64 */
    163   state[0] += a;
    164   state[1] += b;
    165   state[2] += c;
    166   state[3] += d;
    167 }
    168 
    169 
    170 unsigned char plaintext_bytes[]="admin";//after encoding: 21232f297a57a5a743894a0e4a801fc3
    171 unsigned char ciphertext_bytes[16];
    172 void md5_test(void)
    173 {
    174   //object define
    175   MD5_CTX my_md5;
    176   //init object
    177   MD5Init(&my_md5);
    178   //encoding
    179   MD5Update(&my_md5,plaintext_bytes,strlen((char*)plaintext_bytes));
    180   MD5Final(&my_md5,ciphertext_bytes);
    181   
    182 }
    183 
    184 
    185 
    186 
    187 //==================== end of file ========================
    md5.c

     

  5. 因为32位机器 unsigned int == 32bits 为16位机器 unsigned int == 16bits 所以需要将 unsigned int ---- unsigned long 转换.

 

谢谢。

end.

标签:16,void,unsigned,long,char,机器运行,context,input,md5
来源: https://www.cnblogs.com/lumao1122-Milolu/p/13223663.html

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。

专注分享技术,共同学习,共同进步。侵权联系[81616952@qq.com]

Copyright (C)ICode9.com, All Rights Reserved.

ICode9版权所有