【安全算法之SHA512】SHA512摘要运算C语言源码实现

【安全算法之SHA512】SHA512摘要运算的C语言源码实现

• 概述
• 头文件定义
• C语言版本的实现源码
• 测试用例
• github仓库
• 更多参考链接

概述

大家都知道摘要算法在安全领域，也是一个特别重要的存在，而SHA512是其中比较常见的一种摘要算法，它的特点就是计算复杂度较低，不等长的数据原文输入，可以得出等长的摘要值，这个值是固定为64字节。正是由于这种特殊性，很多重要的数据完整性校验领域，都可以看到SHAxxx的影子。由于它的摘要值长度比较长，且相对于其他SHA算法，它的计算复杂度会高些，所以使用场景不算特别多。
今天给大家带来SHA512的C源码版本实现，欢迎大家深入学习和讨论。

头文件定义

头文件定义如下，主要定义了SHA512的上下文结构体，以及导出的三个API：

#ifndef __SHA512_H__
#define __SHA512_H__

#include 

#define SHA512_DIGEST_LEN 64         	// SHA512 outputs a 64 byte digest

typedef struct _sha512_ctx_t {
	uint64_t 	total[2];          		/*!< number of bytes processed  */
    uint64_t 	state[8];          		/*!< intermediate digest state  */
    uint8_t 	buffer[128];  			/*!< data block being processed */
    int32_t		is_384;             	/*!< 0 => SHA-512, else SHA-384 */
} sha512_ctx_t;

void crypto_sha512_init(sha512_ctx_t *ctx);
void crypto_sha512_update(sha512_ctx_t *ctx, const uint8_t *data, uint32_t len);
void crypto_sha512_final(sha512_ctx_t *ctx, uint8_t *digest);

#endif   // __SHA512_H__

C语言版本的实现源码

下面是SHA512的C语言版本实现，主要也是围绕导出的3个API：

#include 
#include "sha512.h"

#if defined(_MSC_VER) || defined(__WATCOMC__)
  #define UL64(x) x##ui64
#else
  #define UL64(x) x##ULL
#endif

#define SHA512_VALIDATE_RET(cond)     	            \
  	do {                                            \
        if( !(cond) )                               \
        {                                           \
            return( -1 );                           \
        }                                           \
    } while( 0 )
#define SHA512_VALIDATE(cond) 			            \
   	do {                                            \
        if( !(cond) )                               \
        {                                           \
            return;                                 \
        }                                           \
    } while( 0 )

/*
 * 64-bit integer manipulation macros (big endian)
 */
#ifndef GET_UINT64_BE
#define GET_UINT64_BE(n,b,i)                   	  \
{                                                 \
    (n) = ( (uint64_t) (b)[(i)    ] << 56 )       \
        | ( (uint64_t) (b)[(i) + 1] << 48 )       \
        | ( (uint64_t) (b)[(i) + 2] << 40 )       \
        | ( (uint64_t) (b)[(i) + 3] << 32 )       \
        | ( (uint64_t) (b)[(i) + 4] << 24 )       \
        | ( (uint64_t) (b)[(i) + 5] << 16 )       \
        | ( (uint64_t) (b)[(i) + 6] <<  8 )       \
        | ( (uint64_t) (b)[(i) + 7]       );      \
}
#endif /* GET_UINT64_BE */

#ifndef PUT_UINT64_BE
#define PUT_UINT64_BE(n,b,i)                            \
{                                                       \
    (b)[(i)    ] = (uint8_t) ( (n) >> 56 );       \
    (b)[(i) + 1] = (uint8_t) ( (n) >> 48 );       \
    (b)[(i) + 2] = (uint8_t) ( (n) >> 40 );       \
    (b)[(i) + 3] = (uint8_t) ( (n) >> 32 );       \
    (b)[(i) + 4] = (uint8_t) ( (n) >> 24 );       \
    (b)[(i) + 5] = (uint8_t) ( (n) >> 16 );       \
    (b)[(i) + 6] = (uint8_t) ( (n) >>  8 );       \
    (b)[(i) + 7] = (uint8_t) ( (n)       );       \
}
#endif /* PUT_UINT64_BE */

/*
 * Round constants
 */
static const uint64_t K[80] =
{
    UL64(0x428A2F98D728AE22),  UL64(0x7137449123EF65CD),
    UL64(0xB5C0FBCFEC4D3B2F),  UL64(0xE9B5DBA58189DBBC),
    UL64(0x3956C25BF348B538),  UL64(0x59F111F1B605D019),
    UL64(0x923F82A4AF194F9B),  UL64(0xAB1C5ED5DA6D8118),
    UL64(0xD807AA98A3030242),  UL64(0x12835B0145706FBE),
    UL64(0x243185BE4EE4B28C),  UL64(0x550C7DC3D5FFB4E2),
    UL64(0x72BE5D74F27B896F),  UL64(0x80DEB1FE3B1696B1),
    UL64(0x9BDC06A725C71235),  UL64(0xC19BF174CF692694),
    UL64(0xE49B69C19EF14AD2),  UL64(0xEFBE4786384F25E3),
    UL64(0x0FC19DC68B8CD5B5),  UL64(0x240CA1CC77AC9C65),
    UL64(0x2DE92C6F592B0275),  UL64(0x4A7484AA6EA6E483),
    UL64(0x5CB0A9DCBD41FBD4),  UL64(0x76F988DA831153B5),
    UL64(0x983E5152EE66DFAB),  UL64(0xA831C66D2DB43210),
    UL64(0xB00327C898FB213F),  UL64(0xBF597FC7BEEF0EE4),
    UL64(0xC6E00BF33DA88FC2),  UL64(0xD5A79147930AA725),
    UL64(0x06CA6351E003826F),  UL64(0x142929670A0E6E70),
    UL64(0x27B70A8546D22FFC),  UL64(0x2E1B21385C26C926),
    UL64(0x4D2C6DFC5AC42AED),  UL64(0x53380D139D95B3DF),
    UL64(0x650A73548BAF63DE),  UL64(0x766A0ABB3C77B2A8),
    UL64(0x81C2C92E47EDAEE6),  UL64(0x92722C851482353B),
    UL64(0xA2BFE8A14CF10364),  UL64(0xA81A664BBC423001),
    UL64(0xC24B8B70D0F89791),  UL64(0xC76C51A30654BE30),
    UL64(0xD192E819D6EF5218),  UL64(0xD69906245565A910),
    UL64(0xF40E35855771202A),  UL64(0x106AA07032BBD1B8),
    UL64(0x19A4C116B8D2D0C8),  UL64(0x1E376C085141AB53),
    UL64(0x2748774CDF8EEB99),  UL64(0x34B0BCB5E19B48A8),
    UL64(0x391C0CB3C5C95A63),  UL64(0x4ED8AA4AE3418ACB),
    UL64(0x5B9CCA4F7763E373),  UL64(0x682E6FF3D6B2B8A3),
    UL64(0x748F82EE5DEFB2FC),  UL64(0x78A5636F43172F60),
    UL64(0x84C87814A1F0AB72),  UL64(0x8CC702081A6439EC),
    UL64(0x90BEFFFA23631E28),  UL64(0xA4506CEBDE82BDE9),
    UL64(0xBEF9A3F7B2C67915),  UL64(0xC67178F2E372532B),
    UL64(0xCA273ECEEA26619C),  UL64(0xD186B8C721C0C207),
    UL64(0xEADA7DD6CDE0EB1E),  UL64(0xF57D4F7FEE6ED178),
    UL64(0x06F067AA72176FBA),  UL64(0x0A637DC5A2C898A6),
    UL64(0x113F9804BEF90DAE),  UL64(0x1B710B35131C471B),
    UL64(0x28DB77F523047D84),  UL64(0x32CAAB7B40C72493),
    UL64(0x3C9EBE0A15C9BEBC),  UL64(0x431D67C49C100D4C),
    UL64(0x4CC5D4BECB3E42B6),  UL64(0x597F299CFC657E2A),
    UL64(0x5FCB6FAB3AD6FAEC),  UL64(0x6C44198C4A475817)
};

void crypto_sha384_sha512_init(sha512_ctx_t *ctx, int32_t is_384)
{
    SHA512_VALIDATE( ctx != NULL );

    memset( ctx, 0, sizeof( sha512_ctx_t ) );

    ctx->total[0] = 0;
    ctx->total[1] = 0;

    if( is_384 == 0 ) {
        /* SHA-512 */
        ctx->state[0] = UL64(0x6A09E667F3BCC908);
        ctx->state[1] = UL64(0xBB67AE8584CAA73B);
        ctx->state[2] = UL64(0x3C6EF372FE94F82B);
        ctx->state[3] = UL64(0xA54FF53A5F1D36F1);
        ctx->state[4] = UL64(0x510E527FADE682D1);
        ctx->state[5] = UL64(0x9B05688C2B3E6C1F);
        ctx->state[6] = UL64(0x1F83D9ABFB41BD6B);
        ctx->state[7] = UL64(0x5BE0CD19137E2179);
    } else {
        /* SHA-384 */
        ctx->state[0] = UL64(0xCBBB9D5DC1059ED8);
        ctx->state[1] = UL64(0x629A292A367CD507);
        ctx->state[2] = UL64(0x9159015A3070DD17);
        ctx->state[3] = UL64(0x152FECD8F70E5939);
        ctx->state[4] = UL64(0x67332667FFC00B31);
        ctx->state[5] = UL64(0x8EB44A8768581511);
        ctx->state[6] = UL64(0xDB0C2E0D64F98FA7);
        ctx->state[7] = UL64(0x47B5481DBEFA4FA4);
    }

    ctx->is_384 = is_384;
}

void crypto_sha512_init( sha512_ctx_t *ctx )
{
	crypto_sha384_sha512_init(ctx, 0);
}

static int32_t local_sha512_process( sha512_ctx_t *ctx,
                                     const uint8_t data[128] )
{
    int32_t i;
    uint64_t temp1, temp2, W[80];
    uint64_t A, B, C, D, E, F, G, H;

    SHA512_VALIDATE_RET( ctx != NULL );
    SHA512_VALIDATE_RET( (const uint8_t *)data != NULL );

#define  SHR(x,n) (x >> n)
#define ROTR(x,n) (SHR(x,n) | (x << (64 - n)))

#define S0(x) (ROTR(x, 1) ^ ROTR(x, 8) ^  SHR(x, 7))
#define S1(x) (ROTR(x,19) ^ ROTR(x,61) ^  SHR(x, 6))

#define S2(x) (ROTR(x,28) ^ ROTR(x,34) ^ ROTR(x,39))
#define S3(x) (ROTR(x,14) ^ ROTR(x,18) ^ ROTR(x,41))

#define F0(x,y,z) ((x & y) | (z & (x | y)))
#define F1(x,y,z) (z ^ (x & (y ^ z)))

#define P(a,b,c,d,e,f,g,h,x,K)                  \
{                                               \
    temp1 = h + S3(e) + F1(e,f,g) + K + x;      \
    temp2 = S2(a) + F0(a,b,c);                  \
    d += temp1; h = temp1 + temp2;              \
}

    for( i = 0; i < 16; i++ ) {
        GET_UINT64_BE( W[i], data, i << 3 );
    }

    for( ; i < 80; i++ ) {
        W[i] = S1(W[i -  2]) + W[i -  7] +
               S0(W[i - 15]) + W[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];
    i = 0;

    do {
        P( A, B, C, D, E, F, G, H, W[i], K[i] ); i++;
        P( H, A, B, C, D, E, F, G, W[i], K[i] ); i++;
        P( G, H, A, B, C, D, E, F, W[i], K[i] ); i++;
        P( F, G, H, A, B, C, D, E, W[i], K[i] ); i++;
        P( E, F, G, H, A, B, C, D, W[i], K[i] ); i++;
        P( D, E, F, G, H, A, B, C, W[i], K[i] ); i++;
        P( C, D, E, F, G, H, A, B, W[i], K[i] ); i++;
        P( B, C, D, E, F, G, H, A, W[i], K[i] ); i++;
    } while( i < 80 );

    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;

    return( 0 );
}

/*
 * SHA-512 process buffer
 */
void crypto_sha512_update( sha512_ctx_t *ctx,
                               const uint8_t *data,
                               uint32_t len )
{
    int32_t ret;
    uint32_t fill;
    uint32_t left;

    SHA512_VALIDATE( ctx != NULL );
    SHA512_VALIDATE( len == 0 || data != NULL );

    left = (uint32_t) (ctx->total[0] & 0x7F);
    fill = 128 - left;

    ctx->total[0] += (uint64_t) len;

    if( ctx->total[0] < (uint64_t) len ) {
        ctx->total[1]++;
    }

    if( left && len >= fill ) {
        memcpy( (void *) (ctx->buffer + left), data, fill );

        if( ( ret = local_sha512_process( ctx, ctx->buffer ) ) != 0 ) {
        	/* error */
            return ;
        }

        data += fill;
        len  -= fill;
        left = 0;
    }

    while( len >= 128 ) {
        if( ( ret = local_sha512_process( ctx, data ) ) != 0 ) {
            /* error */
            return ;
        }

        data += 128;
        len  -= 128;
    }

    if( len > 0 ) {
        memcpy( (void *) (ctx->buffer + left), data, len );
    }
}

/*
 * SHA-512 final digest
 */
void crypto_sha512_final( sha512_ctx_t *ctx, uint8_t *digest )
{
    int32_t ret;
    unsigned used;
    uint64_t high, low;

    SHA512_VALIDATE( ctx != NULL );
    SHA512_VALIDATE( (uint8_t *)digest != NULL );

    /*
     * Add padding: 0x80 then 0x00 until 16 bytes remain for the length
     */
    used = ctx->total[0] & 0x7F;

    ctx->buffer[used++] = 0x80;

    if( used <= 112 ) {
        /* Enough room for padding + length in current block */
        memset( ctx->buffer + used, 0, 112 - used );
    } else {
        /* We'll need an extra block */
        memset( ctx->buffer + used, 0, 128 - used );

        if( ( ret = local_sha512_process( ctx, ctx->buffer ) ) != 0 ) {
            /* error */
            return ;
        }

        memset( ctx->buffer, 0, 112 );
    }

    /*
     * Add message length
     */
    high = ( ctx->total[0] >> 61 )
         | ( ctx->total[1] <<  3 );
    low  = ( ctx->total[0] <<  3 );

    PUT_UINT64_BE( high, ctx->buffer, 112 );
    PUT_UINT64_BE( low,  ctx->buffer, 120 );

    if( ( ret = local_sha512_process( ctx, ctx->buffer ) ) != 0 ) {
     	/* error */
            return ;
    }

    /*
     * Output final state
     */
    PUT_UINT64_BE( ctx->state[0], digest,  0 );
    PUT_UINT64_BE( ctx->state[1], digest,  8 );
    PUT_UINT64_BE( ctx->state[2], digest, 16 );
    PUT_UINT64_BE( ctx->state[3], digest, 24 );
    PUT_UINT64_BE( ctx->state[4], digest, 32 );
    PUT_UINT64_BE( ctx->state[5], digest, 40 );

    if( ctx->is_384 == 0 ) {
        PUT_UINT64_BE( ctx->state[6], digest, 48 );
        PUT_UINT64_BE( ctx->state[7], digest, 56 );
    }
}

测试用例

针对SHA512导出的三个接口，我编写了以下测试用例：

#include 
#include 

#include "sha512.h"
#include "convert.h"

int log_hexdump(const char *title, const unsigned char *data, int len)
{
    char str[160], octet[10];
    int ofs, i, k, d;
    const unsigned char *buf = (const unsigned char *)data;
    const char dimm[] = "+------------------------------------------------------------------------------+";

    printf("%s (%d bytes):\r\n", title, len);
    printf("%s\r\n", dimm);
    printf("| Offset  : 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F   0123456789ABCDEF |\r\n");
    printf("%s\r\n", dimm);

    for (ofs = 0; ofs < (int)len; ofs += 16) {
        d = snprintf( str, sizeof(str), "| %08X: ", ofs );

        for (i = 0; i < 16; i++) {
            if ((i + ofs) < (int)len) {
                snprintf( octet, sizeof(octet), "%02X ", buf[ofs + i] );
            } else {
                snprintf( octet, sizeof(octet), "   " );
            }

            d += snprintf( &str[d], sizeof(str) - d, "%s", octet );
        }
        d += snprintf( &str[d], sizeof(str) - d, "  " );
        k = d;

        for (i = 0; i < 16; i++) {
            if ((i + ofs) < (int)len) {
                str[k++] = (0x20 <= (buf[ofs + i]) &&  (buf[ofs + i]) <= 0x7E) ? buf[ofs + i] : '.';
            } else {
                str[k++] = ' ';
            }
        }

        str[k] = '\0';
        printf("%s |\r\n", str);
    }

    printf("%s\r\n", dimm);

    return 0;
}

int main(int argc, const char *argv[])
{
	const char *data = "C1D0F8FB4958670DBA40AB1F3752EF0D";
    const char *digest_exp_str = "D2A72FDEFB6C5B3C8DB639869C6BC756EBD11B1D152B29CF55011C31DE0F3807D21C357C583619EE9006B7E4023042200394DC1DDE913463EC6000AA472D8D24";
	uint8_t digest_calc[SHA512_DIGEST_LEN];
    uint8_t digest_exp_hex[SHA512_DIGEST_LEN];
	sha512_ctx_t ctx;
	const char *p_calc = data;
	uint8_t data_bytes[128];
	uint16_t len_bytes;
	char data_str[128];

	if (argc > 1) {
		p_calc = argv[1];
	}

	utils_hex_string_2_bytes(data, data_bytes, &len_bytes);
	log_hexdump("data_bytes", data_bytes, len_bytes);
	utils_bytes_2_hex_string(data_bytes, len_bytes, data_str);
	printf("data_str: %s\n", data_str);
	if (!strcmp(data, data_str)) {
		printf("hex string - bytes convert OK\n");
	} else {
		printf("hex string - bytes convert FAIL\n");
	}

	crypto_sha512_init(&ctx);
	crypto_sha512_update(&ctx, (uint8_t *)p_calc, strlen(p_calc));
	crypto_sha512_final(&ctx, digest_calc);

    utils_hex_string_2_bytes(digest_exp_str, digest_exp_hex, &len_bytes);
	if (len_bytes == sizeof(digest_calc) && !memcmp(digest_calc, digest_exp_hex, sizeof(digest_calc))) {
		printf("SHA512 digest test OK\n");
        log_hexdump("digest_calc", digest_calc, sizeof(digest_calc));
	} else {
		log_hexdump("digest_calc", digest_calc, sizeof(digest_calc));
		log_hexdump("digest_exp", digest_exp_hex, sizeof(digest_exp_hex));
		printf("SHA512 digest test FAIL\n");
	}

	return 0;
}

测试用例比较简单，就是对字符串C1D0F8FB4958670DBA40AB1F3752EF0D进行SHA1运算，期望的摘要结果的hexstring是D2A72FDEFB6C5B3C8DB639869C6BC756EBD11B1D152B29CF55011C31DE0F3807D21C357C583619EE9006B7E4023042200394DC1DDE913463EC6000AA472D8D24，这个期望值是用算法工具算出来的。
先用API接口算出摘要值，再与期望值比较，这里有个hexstringtobyte的转换，如果比较一致则表示API计算OK；反之，接口计算失败。
同时，也欢迎大家设计提供更多的测试案例代码。

github仓库

以上代码和测试用例，及编译运行等，可以参考我的github仓库，有详细的流程介绍，欢迎大家交流讨论。如果有帮助到你的话，记得帮忙点亮一颗星哦。

更多参考链接

[1] 【安全算法的github仓库】
[2] 【安全算法之概述】一文带你简要了解常见常用的安全算法