hmacsha1.c

比较好的代码

#include "sha1.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>

#ifndef SHA_DIGESTSIZE
#define SHA_DIGESTSIZE 20
#endif

#ifndef SHA_BLOCKSIZE
#define SHA_BLOCKSIZE 64
#endif


/* Hash a single 512-bit block. This is the core of the algorithm. */

void SHA1Transform(__u32 state[5], __u8 buffer[64])
{
__u32 a, b, c, d, e;
typedef union {
    unsigned char c[64];
    __u32 l[16];
} CHAR64LONG16;

CHAR64LONG16* block;

#ifdef SHA1HANDSOFF

static unsigned char workspace[64];
    block = (CHAR64LONG16*)workspace;
//    NdisMoveMemory(block, buffer, 64);
    memcpy(block, buffer, 64);
#else
    block = (CHAR64LONG16*)buffer;
#endif
    /* Copy context->state[] to working vars */
    a = state[0];
    b = state[1];
    c = state[2];
    d = state[3];
    e = state[4];
    /* 4 rounds of 20 operations each. Loop unrolled. */
    R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
    R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
    R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
    R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
    R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
    R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
    R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
    R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
    R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
    R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
    R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
    R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
    R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
    R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
    R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
    R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
    R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
    R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
    R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
    R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
    /* Add the working vars back into context.state[] */
    state[0] += a;
    state[1] += b;
    state[2] += c;
    state[3] += d;
    state[4] += e;
    /* Wipe variables */
    a = b = c = d = e = 0;
}


/* SHA1Init - Initialize new context */

void SHA1Init(SHA1_CTX* context)
{
    /* SHA1 initialization constants */
    context->state[0] = 0x67452301;
    context->state[1] = 0xEFCDAB89;
    context->state[2] = 0x98BADCFE;
    context->state[3] = 0x10325476;
    context->state[4] = 0xC3D2E1F0;
    context->count[0] = context->count[1] = 0;
}


/* Run your data through this. */

void SHA1Update(SHA1_CTX* context, unsigned char* data, __u32 len)
{
	__u32 i, j;

    j = context->count[0];
    if ((context->count[0] += len << 3) < j)
	context->count[1]++;
    context->count[1] += (len>>29);
    j = (j >> 3) & 63;
    if ((j + len) > 63) {
//        NdisMoveMemory(&context->buffer[j], data, (i = 64-j));
        memcpy(&context->buffer[j], data, (i = 64-j));
        SHA1Transform(context->state, context->buffer);
        for ( ; i + 63 < len; i += 64) {
            SHA1Transform(context->state, &data[i]);
        }
        j = 0;
    }
    else i = 0;
//    NdisMoveMemory(&context->buffer[j], &data[i], len - i);
    memcpy(&context->buffer[j], &data[i], len - i);
}


/* Add padding and return the message digest. */

void SHA1Final(unsigned char digest[20], SHA1_CTX* context)
{
__u32 i, j;
unsigned char finalcount[8];

    for (i = 0; i < 8; i++) {
        finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
         >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
    }
    SHA1Update(context, (unsigned char *)"\200", 1);
    while ((context->count[0] & 504) != 448) {
        SHA1Update(context, (unsigned char *)"\0", 1);
    }
    SHA1Update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
    for (i = 0; i < 20; i++) {
        digest[i] = (unsigned char)
         ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
    }
    /* Wipe variables */
    i = j = 0;
//    NdisZeroMemory(context->buffer, 64);
//    NdisZeroMemory(context->state, 20);
//    NdisZeroMemory(context->count, 8);
//    NdisZeroMemory(&finalcount, 8);
    memset(context->buffer, 0x00, 64);
    memset(context->state, 0x00, 20);
    memset(context->count, 0x00, 8);
    memset(&finalcount, 0x00, 8);
    
#ifdef SHA1HANDSOFF  /* make SHA1Transform overwrite its own static vars */
    SHA1Transform(context->state, context->buffer);
#endif
}



/* Function to print the digest */
void pr_sha(FILE* fp, unsigned char* s, int t)
{
    int i ;

	for(i=0;i<t;i++)
		printf("%02x",s[i]);	
	printf("\n");
	/*
	fprintf(fp, "0x") ;
	for (i = 0 ; i < t ; i++)
	{
		fprintf(fp, "%02x", s[i]) ;
		printf("\n");
	}
	fprintf(fp, "0") ;
	*/
}

void truncate
(
	char* d1, /* data to be truncated */
	char* d2, /* truncated data */
	int len /* length in bytes to keep */
)
{
	int i ;
	for (i = 0 ; i < len ; i++) d2[i] = d1[i];
}

/* Function to compute the digest */
void hmac_sha
(
	char* k, /* secret key */
	int lk, /* length of the key in bytes */
	char* d, /* data */
	int ld, /* length of data in bytes */
	char* out, /* output buffer, at least "t" bytes */
	int t
)
{
	SHA1_CTX ictx, octx ;
	char isha[SHA_DIGESTSIZE], osha[SHA_DIGESTSIZE] ;
	char key[SHA_DIGESTSIZE] ;
	char buf[SHA_BLOCKSIZE] ;
	int i ;

	if (lk > SHA_BLOCKSIZE) {

	SHA1_CTX tctx ;

	SHA1Init(&tctx) ;
	SHA1Update(&tctx, k, lk) ;
	SHA1Final(key, &tctx) ;

	k = key ;
	lk = SHA_DIGESTSIZE ;
}

/**** Inner Digest ****/

	SHA1Init(&ictx) ;

	/* Pad the key for inner digest */
	for (i = 0 ; i < lk ; ++i) buf[i] = k[i] ^ 0x36 ;
	for (i = lk ; i < SHA_BLOCKSIZE ; ++i) buf[i] = 0x36 ;

	SHA1Update(&ictx, buf, SHA_BLOCKSIZE) ;
	SHA1Update(&ictx, d, ld) ;

	SHA1Final(isha, &ictx) ;

/**** Outter Digest ****/

	SHA1Init(&octx) ;

/* Pad the key for outter digest */

	for (i = 0 ; i < lk ; ++i) buf[i] = k[i] ^ 0x5C ;
	for (i = lk ; i < SHA_BLOCKSIZE ; ++i) buf[i] = 0x5C ;

	SHA1Update(&octx, buf, SHA_BLOCKSIZE) ;
	SHA1Update(&octx, isha, SHA_DIGESTSIZE) ;

	SHA1Final(osha, &octx) ;

/* truncate and print the results */
	t = t > SHA_DIGESTSIZE ? SHA_DIGESTSIZE : t ;
	truncate(osha, out, t) ;
	pr_sha(stdout, out, t) ;

}


int main()
{
	char k[1024],d[1024],out[1024];
	int lk,ld,t;
	strcpy(d,"what do ya want for nothing?");
	strcpy(k,"Jefe");
	lk=strlen(k);
	ld=strlen(d);
	printf("lk=%d\n",lk);
	printf("ld=%d\n",ld);
	t=20;
	hmac_sha(k,lk,d,ld,out,t);

	return 0;
}