#include "stdlib.h"
//sha256.h
#define SHA256_BLOCK_SIZE 32 //SHA 256bits = 32Bytes
typedef unsigned char uint8_t;
typedef unsigned int uint32_t;
typedef struct
{
uint8_t data[64];
uint32_t datalen;
unsigned long long bitlen;
uint32_t state[8];
} sha256_ctx_t;
//api
extern void sha256_init(sha256_ctx_t *ctx);
extern void sha256_update(sha256_ctx_t *ctx, const uint8_t data[], uint32_t len);
extern void sha256_final(sha256_ctx_t *ctx, uint8_t hash[]);
//sha256.c
/****************************** MACROS ******************************/
#define ROTLEFT(a,b) (((a) << (b)) | ((a) >> (32-(b))))
#define ROTRIGHT(a,b) (((a) >> (b)) | ((a) << (32-(b))))
#define CH(x,y,z) (((x) & (y)) ^ (~(x) & (z)))
#define MAJ(x,y,z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
#define EP0(x) (ROTRIGHT(x,2) ^ ROTRIGHT(x,13) ^ ROTRIGHT(x,22))
#define EP1(x) (ROTRIGHT(x,6) ^ ROTRIGHT(x,11) ^ ROTRIGHT(x,25))
#define SIG0(x) (ROTRIGHT(x,7) ^ ROTRIGHT(x,18) ^ ((x) >> 3))
#define SIG1(x) (ROTRIGHT(x,17) ^ ROTRIGHT(x,19) ^ ((x) >> 10))
/**************************** VARIABLES *****************************/
static const uint32_t k[64] =
{
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
};
static void sha256_transform(sha256_ctx_t *ctx, const uint8_t data[])
{
uint32_t a, b, c, d, e, f, g, h, i, j, t1, t2, m[64];
for(i = 0, j = 0; i < 16; ++i, j += 4)
{
m[i] = (data[j] << 24) | (data[j + 1] << 16) | (data[j + 2] << 8) | (data[j + 3]);
}
for(; i < 64; ++i)
{
m[i] = SIG1(m[i - 2]) + m[i - 7] + SIG0(m[i - 15]) + m[i - 16];
}
a = ctx->state[0];
b = ctx->state[1];
c = ctx->state[2];
d = ctx->state[3];
e = ctx->state[4];
f = ctx->state[5];
g = ctx->state[6];
h = ctx->state[7];
for(i = 0; i < 64; ++i)
{
t1 = h + EP1(e) + CH(e, f, g) + k[i] + m[i];
t2 = EP0(a) + MAJ(a, b, c);
h = g;
g = f;
f = e;
e = d + t1;
d = c;
c = b;
b = a;
a = t1 + t2;
}
ctx->state[0] += a;
ctx->state[1] += b;
ctx->state[2] += c;
ctx->state[3] += d;
ctx->state[4] += e;
ctx->state[5] += f;
ctx->state[6] += g;
ctx->state[7] += h;
}
void sha256_init(sha256_ctx_t *ctx)
{
ctx->datalen = 0;
ctx->bitlen = 0;
ctx->state[0] = 0x6a09e667;
ctx->state[1] = 0xbb67ae85;
ctx->state[2] = 0x3c6ef372;
ctx->state[3] = 0xa54ff53a;
ctx->state[4] = 0x510e527f;
ctx->state[5] = 0x9b05688c;
ctx->state[6] = 0x1f83d9ab;
ctx->state[7] = 0x5be0cd19;
}
void sha256_update(sha256_ctx_t *ctx, const uint8_t data[], uint32_t len)
{
uint32_t i;
for(i = 0; i < len; ++i)
{
ctx->data[ctx->datalen] = data[i];
ctx->datalen++;
if(ctx->datalen == 64)
{
sha256_transform(ctx, ctx->data);
ctx->bitlen += 512;
ctx->datalen = 0;
}
}
}
void sha256_final(sha256_ctx_t *ctx, uint8_t hash[])
{
uint32_t i;
i = ctx->datalen;
// Pad whatever data is left in the buffer.
if(ctx->datalen < 56)
{
ctx->data[i++] = 0x80;
while(i < 56)
{
ctx->data[i++] = 0x00;
}
}
else
{
ctx->data[i++] = 0x80;
while(i < 64)
{
ctx->data[i++] = 0x00;
}
sha256_transform(ctx, ctx->data);
memset(ctx->data, 0, 56);
}
// Append to the padding the total message's length in bits and transform.
ctx->bitlen += ctx->datalen * 8;
ctx->data[63] = ctx->bitlen;
ctx->data[62] = ctx->bitlen >> 8;
ctx->data[61] = ctx->bitlen >> 16;
ctx->data[60] = ctx->bitlen >> 24;
ctx->data[59] = ctx->bitlen >> 32;
ctx->data[58] = ctx->bitlen >> 40;
ctx->data[57] = ctx->bitlen >> 48;
ctx->data[56] = ctx->bitlen >> 56;
sha256_transform(ctx, ctx->data);
// Since this implementation uses little endian byte ordering and SHA uses big endian,
// reverse all the bytes when copying the final state to the output hash.
for(i = 0; i < 4; ++i)
{
hash[i] = (ctx->state[0] >> (24 - i * 8)) & 0x000000ff;
hash[i + 4] = (ctx->state[1] >> (24 - i * 8)) & 0x000000ff;
hash[i + 8] = (ctx->state[2] >> (24 - i * 8)) & 0x000000ff;
hash[i + 12] = (ctx->state[3] >> (24 - i * 8)) & 0x000000ff;
hash[i + 16] = (ctx->state[4] >> (24 - i * 8)) & 0x000000ff;
hash[i + 20] = (ctx->state[5] >> (24 - i * 8)) & 0x000000ff;
hash[i + 24] = (ctx->state[6] >> (24 - i * 8)) & 0x000000ff;
hash[i + 28] = (ctx->state[7] >> (24 - i * 8)) & 0x000000ff;
}
}
/***********************************************************************/
//test
void log(char *head, uint8_t *data, uint8_t len)
{
uint8_t i;
printf("%s:", head);
for(i = 0; i < len; i++)
{
printf("%02X ", data[i]);
}
printf("\r\n");
}
int main(int argc, char *argv[])
{
uint8_t buff1[] = {"embedded-system"};
uint8_t buff2[] = {0x00, 0x65, 0x00, 0x6D, 0x00, 0x62, 0x00, 0x65, 0x00, 0x64, 0x00, 0x64, 0x00, 0x65, \
0x00, 0x64, 0x00, 0x2D, 0x00, 0x73, 0x00, 0x79, 0x00, 0x73, 0x00, 0x74, 0x00, 0x65, 0x00, 0x6D
};
uint8_t sha256_result[32] = {0};
sha256_ctx_t sha;
sha256_init(&sha);
sha256_update(&sha, buff1, strlen(buff1));
sha256_final(&sha, sha256_result);
log("buff1 sha256", sha256_result, 32);
sha256_init(&sha);
sha256_update(&sha, buff2, sizeof(buff2));
sha256_final(&sha, sha256_result);
log("buff2 sha256", sha256_result, 32);
sha256_init(&sha);
sha256_update(&sha, buff1, strlen(buff1));
sha256_update(&sha, buff1, strlen(buff1));
sha256_update(&sha, buff1, strlen(buff1));
sha256_final(&sha, sha256_result);
log("buff1*3 sha256", sha256_result, 32);
return 0;
}
楼主
标题置顶
标题高亮
