一、简介
本文以添加自定义算法EVP_ssf33为例,介绍在OpenSSL中添加自定义加密算法的方法
二、步骤
1、修改crypto/object/objects.txt,注册算法OID,如下:
rsadsi 3 255 : SSF33 : ssf33
2、进入目录:crypto/object/,执行如下命令,生成算法的声明
perl objects.pl objects.txt obj_mac.num obj_mac.h
3、在crypto/evp/下添加e_ssf33.c,内容如下
#include <stdio.h>
#include “cryptlib.h”
#ifndef OPENSSL_NO_RC4
#include <openssl/evp.h>
#include <openssl/objects.h>
#include <openssl/rc4.h>
/* FIXME: surely this is available elsewhere? */
#define EVP_SSF33_KEY_SIZE 16
typedef struct
{
RC4_KEY ks; /* working key */
} EVP_SSF33_KEY;
#define data(ctx) ((EVP_SSF33_KEY *)(ctx)->cipher_data)
static int ssf33_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv,int enc);
static int ssf33_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, const unsigned char *in, unsigned int inl);
static const EVP_CIPHER ssf33_evp_cipher=
{
NID_ssf33,
1,
EVP_SSF33_KEY_SIZE,
0,
EVP_CIPH_VARIABLE_LENGTH,
ssf33_init_key,
ssf33_cipher,
NULL,
sizeof(EVP_SSF33_KEY),
NULL,
NULL,
NULL,
NULL
};
const EVP_CIPHER *EVP_ssf33(void)
{
return(&ssf33_evp_cipher);
}
static int ssf33_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key, const unsigned char *iv, int enc)
{
RC4_set_key(&data(ctx)->ks,EVP_CIPHER_CTX_key_length(ctx), key);
return 1;
}
static int ssf33_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, const unsigned char *in, unsigned int inl)
{
RC4(&data(ctx)->ks,inl,in,out);
return 1;
}
#endif
4、修改crypto/evp/evp.h,添加对算法的声明,如下
const EVP_CIPHER *EVP_ssf33(void);
5、修改crypto/evp/c_allc.c,在OpenSSL_add_all_ciphers函数中使用EVP_add_cipher注册加密函数,如下
EVP_add_cipher(EVP_ssf33());
6、修改crypto/evp/Makefile,如下
7、完成
通过OpenSSL提供FTP+SSL/TLS认证功能,并实现安全数据传输 http://www.linuxidc.com/Linux/2013-05/84986.htm
Linux下使用OpenSSL生成证书 http://www.linuxidc.com/Linux/2015-05/117034.htm
利用OpenSSL签署多域名证书 http://www.linuxidc.com/Linux/2014-10/108222.htm
OpenSSL 的详细介绍:请点这里
OpenSSL 的下载地址:请点这里
本文永久更新链接地址:http://www.linuxidc.com/Linux/2015-08/121749.htm