SHA1算法 C语言实现

SHA1算法 C语言实现

实现了计算字符串，文件的SHA1值
算法来自百度百科

代码如下：

#include <stdio.h>#include <stdlib.h>#define SHA1_ROTL(a,b) (SHA1_tmp=(a),((SHA1_tmp>>(32-b))&(0x7fffffff>>(31-b)))|(SHA1_tmp<<b))#define SHA1_F(B,C,D,t) ((t<40)?((t<20)?((B&C)|((~B)&D)):(B^C^D)):((t<60)?((B&C)|(B&D)|(C&D)):(B^C^D)))long SHA1_tmp;extern char* StrSHA1(const char* str, long long length, char* sha1){    /*    计算字符串SHA-1    参数说明：    str         字符串指针    length      字符串长度    sha1         用于保存SHA-1的字符串指针    返回值为参数sha1    */    char *pp, *ppend;    long l, i, K[80], W[80], TEMP, A, B, C, D, E, H0, H1, H2, H3, H4;    H0 = 0x67452301, H1 = 0xEFCDAB89, H2 = 0x98BADCFE, H3 = 0x10325476, H4 = 0xC3D2E1F0;    for (i = 0; i < 20; K[i++] = 0x5A827999);    for (i = 20; i < 40; K[i++] = 0x6ED9EBA1);    for (i = 40; i < 60; K[i++] = 0x8F1BBCDC);    for (i = 60; i < 80; K[i++] = 0xCA62C1D6);    l = length + ((length % 64 > 56) ? (128 - length % 64) : (64 - length % 64));    if (!(pp = (char*)malloc((unsigned long)l))) return 0;    for (i = 0; i < length; pp[i + 3 - 2 * (i % 4)] = str[i], i++);    for (pp[i + 3 - 2 * (i % 4)] = 128,i++; i < l; pp[i + 3 - 2 * (i % 4)] = 0,i++);    *((long*)(pp + l - 4)) = length << 3;    *((long*)(pp + l - 8)) = length >> 29;    for (ppend = pp + l; pp < ppend; pp += 64){        for (i = 0; i < 16; W[i] = ((long*)pp)[i], i++);        for (i = 16; i < 80; W[i] = SHA1_ROTL((W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16]), 1), i++);        A = H0, B = H1, C = H2, D = H3, E = H4;        for (i = 0; i < 80; i++){            TEMP = SHA1_ROTL(A, 5) + SHA1_F(B, C, D, i) + E + W[i] + K[i];            E = D, D = C, C = SHA1_ROTL(B, 30), B = A, A = TEMP;        }        H0 += A, H1 += B, H2 += C, H3 += D, H4 += E;    }    free(pp - l);    sprintf(sha1, "%08X%08X%08X%08X%08X", H0, H1, H2, H3, H4);     return sh1a;}extern char* FileSHA1(const char* file, char* sha1){    /*    计算文件SHA-1    参数说明：    file        文件路径字符串指针    sha1         用于保存SHA-1的字符串指针    返回值为参数sha1    */    FILE* fh;    char* addlp, T[64];    long addlsize, j, K[80], W[80], TEMP, A, B, C, D, E, H0, H1, H2, H3, H4;    long long length, i, cpys;    void *pp, *ppend;    H0 = 0x67452301, H1 = 0xEFCDAB89, H2 = 0x98BADCFE, H3 = 0x10325476, H4 = 0xC3D2E1F0;    for (i = 0; i < 20; K[i++] = 0x5A827999);    for (i = 20; i < 40; K[i++] = 0x6ED9EBA1);    for (i = 40; i < 60; K[i++] = 0x8F1BBCDC);    for (i = 60; i < 80; K[i++] = 0xCA62C1D6);    fh = fopen(file, "rb");    fseek(fh, 0, SEEK_END);    length = _ftelli64(fh);    addlsize = (56 - length % 64 > 0) ? (64) : (128);    if (!(addlp = (char*)malloc(addlsize))) return 0;    cpys = ((length - (56 - length % 64)) > 0) ? (length - length % 64) : (0);    j = (long)(length - cpys);    if (!(pp = (char*)malloc(j))) return 0;    fseek(fh, -j, SEEK_END);    fread(pp, 1, j, fh);    for (i = 0; i < j; addlp[i + 3 - 2 * (i % 4)] = ((char*)pp)[i], i++);    free(pp);    for (addlp[i + 3 - 2 * (i % 4)] = 128, i++; i < addlsize; addlp[i + 3 - 2 * (i % 4)] = 0, i++);    *((long*)(addlp + addlsize - 4)) = length << 3;    *((long*)(addlp + addlsize - 8)) = length >> 29;    for (rewind(fh); 64 == fread(W, 1, 64, fh);){           for (i = 0; i < 64; T[i + 3 - 2 * (i % 4)] = ((char*)W)[i], i++);        for (i = 0; i < 16; W[i] = ((long*)T)[i], i++);        for (i = 16; i < 80; W[i] = SHA1_ROTL((W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16]), 1), i++);        A = H0, B = H1, C = H2, D = H3, E = H4;        for (i = 0; i < 80; i++){            TEMP = SHA1_ROTL(A, 5) + SHA1_F(B, C, D, i) + E + W[i] + K[i];            E = D, D = C, C = SHA1_ROTL(B, 30), B = A, A = TEMP;        }        H0 += A, H1 += B, H2 += C, H3 += D, H4 += E;    }         for (pp = addlp, ppend = addlp + addlsize; pp < ppend; (long*)pp += 16){        for (i = 0; i < 16; W[i] = ((long*)pp)[i], i++);        for (i = 16; i < 80; W[i] = SHA1_ROTL((W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16]), 1), i++);        A = H0, B = H1, C = H2, D = H3, E = H4;        for (i = 0; i < 80; i++){            TEMP = SHA1_ROTL(A, 5) + SHA1_F(B, C, D, i) + E + W[i] + K[i];            E = D, D = C, C = SHA1_ROTL(B, 30), B = A, A = TEMP;        }        H0 += A, H1 += B, H2 += C, H3 += D, H4 += E;    }    free(addlp); fclose(fh);    sprintf(sha1, "%08X%08X%08X%08X%08X", H0, H1, H2, H3, H4);    return sha1;}

如有不妥之处，欢迎指正~