nginx中使用 md5

core/ngx_md5.h 头文件

/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */

#ifndef _NGX_MD5_H_INCLUDED_
#define _NGX_MD5_H_INCLUDED_

#include <ngx_config.h>
#include <ngx_core.h>

#if (NGX_HAVE_MD5)

#if (NGX_HAVE_OPENSSL_MD5_H)
#include <openssl/md5.h>
#else
#include <md5.h>
#endif

typedef MD5_CTX  ngx_md5_t;

#if (NGX_OPENSSL_MD5)

#define ngx_md5_init    MD5_Init
#define ngx_md5_update  MD5_Update
#define ngx_md5_final   MD5_Final

#else

#define ngx_md5_init    MD5Init
#define ngx_md5_update  MD5Update
#define ngx_md5_final   MD5Final

#endif

#else /* !NGX_HAVE_MD5 */

typedef struct {
    uint64_t  bytes;
    uint32_t  a, b, c, d;
    u_char    buffer[64];
} ngx_md5_t;

void ngx_md5_init(ngx_md5_t *ctx);
void ngx_md5_update(ngx_md5_t *ctx, const void *data, size_t size);
void ngx_md5_final(u_char result[16], ngx_md5_t *ctx);

#endif

#endif /* _NGX_MD5_H_INCLUDED_ */

调用步骤

ngx_md5_init(ngx_md5_t *ctx);

//对长度为size的data数据更新ctx
ngx_md5_update(ngx_md5_t *ctx, const void *data, size_t size);

//产生16字节长的md5值
ngx_md5_final(u_char result[16], ngx_md5_t *ctx);

例子

static int calculate_md5(ngx_str_t *str)
{
	ngx_md5_t     md5;
	int           i;
	char          md5_buf[16], md5_buf2[32], buf[1024];

	if (str->len <= 0 || str->len > sizeof(buf)) {
		return -1;
	}

	memcpy(buf, str->data, str->len);

	ngx_md5_init(&md5);
	ngx_md5_update(&md5, buf, str->len);
	ngx_md5_final(md5_buf, &md5);

	//这里求得的md5_buf是16字节md5值，可以转成32字节的
	for (i = 0; i < 16; i++){
		sprintf(md5_buf2 + i*2, "%02X", md5_buf[i]);
	}

	return 0;
}