利用OpenSSL建立SSL安全通信(C/S)
/******************************************************************************************
*SSL/TLS客户端程序WIN32版(以demos/cli.cpp为基础)
*需要用到动态连接库libeay32.dll,ssleay.dll,
*同时在setting中加入ws2_32.lib libeay32.lib ssleay32.lib,
*以上库文件在编译openssl后可在out32dll目录下找到,
*所需证书文件请参照<<利用Openssl生成证书文件>>自行生成*/
******************************************************************************************/
#include
#include
#include
#include
#include
#include
#include "openssl/rsa.h"
#include "openssl/crypto.h"
#include "openssl/x509.h"
#include "openssl/pem.h"
#include "openssl/ssl.h"
#include "openssl/err.h"
#include "openssl/rand.h"
/*所有需要的参数信息都在此处以#define的形式提供*/
#define CERTF "client.crt" /*客户端的证书(需经CA签名)*/
#define KEYF "client.key" /*客户端的私钥(建议加密存储)*/
#define CACERT "ca.crt" /*CA 的证书*/
#define PORT 1111 /*服务端的端口*/
#define SERVER_ADDR "127.0.0.1" /*服务段的IP地址*/
//检查错误
#define CHK_NULL(x) if ((x)==NULL) { exit (-1); }
#define CHK_ERR(err,s) if ((err)==-1) { perror(s); exit(-2); }
#define CHK_SSL(err) if ((err)==-1) { ERR_print_errors_fp(stderr); exit(-3); }
int main (void)
{
int err;
int sd;
struct sockaddr_in sa;
SSL_CTX* ctx;
SSL* ssl;
X509* server_cert;
char* str;
char buf [4096];
SSL_METHOD *meth;
int seed_int[100]; /*存放随机序列*/
WSADATA wsaData;
//获取SOCKET版本(2.2)
if(WSAStartup(MAKEWORD(2,2),&wsaData) != 0)
{
printf("WSAStartup()fail:%d/n",GetLastError());
return -1;
}
OpenSSL_add_ssl_algorithms(); /*初始化,加载算法*/
SSL_load_error_strings(); /*加载错误信息,为打印调试信息作准备*/
meth = TLSv1_client_method(); /*采用什么协议(SSLv2/SSLv3/TLSv1)在此指定*/
ctx = SSL_CTX_new (meth);
CHK_NULL(ctx);
SSL_CTX_set_verify(ctx,SSL_VERIFY_PEER,NULL); /*验证对方*/
SSL_CTX_load_verify_locations(ctx,CACERT,NULL); /*若验证,则放置CA证书*/
//加载自己的证书client.crt
if (SSL_CTX_use_certificate_file(ctx, CERTF, SSL_FILETYPE_PEM) <= 0)
{
ERR_print_errors_fp(stderr);
exit(-2);
}
//加载自己的密钥文件client.key
if (SSL_CTX_use_PrivateKey_file(ctx, KEYF, SSL_FILETYPE_PEM) <= 0)
{
ERR_print_errors_fp(stderr);
exit(-3);
}
//验证验证密钥与证书是否配对
if (!SSL_CTX_check_private_key(ctx))
{
printf("Private key does not match the certificate public key/n");
exit(-4);
}
/*构建随机数生成机制,WIN32平台必需*/
srand( (unsigned)time( NULL ) );//以时间为种子
for( int i = 0; i < 100;i++ )
{
seed_int[i] = rand();
}
RAND_seed(seed_int, sizeof(seed_int));
/*以下是正常的TCP socket建立过程 .............................. */
printf("Begin tcp socket.../n");
sd = socket (AF_INET, SOCK_STREAM, 0); CHK_ERR(sd, "socket");
memset (&sa, '/0', sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = inet_addr (SERVER_ADDR); /* Server IP */
sa.sin_port = htons (PORT); /* Server Port number */
err = connect(sd, (struct sockaddr*) &sa,sizeof(sa));
CHK_ERR(err, "connect");
/* TCP 连接已建立,开始 SSL 握手过程.......................... */
printf("Begin SSL negotiation n");
ssl = SSL_new (ctx);//建立SSL
CHK_NULL(ssl);
SSL_set_fd (ssl, sd);//关联SSL与SOCKET
err = SSL_connect (ssl);//用SSL连接Server
CHK_SSL(err);
/*打印所有加密算法的信息(可选)*/
printf ("SSL connection using %sn", SSL_get_cipher(ssl));
/*得到服务端的证书并打印些信息(可选) */
server_cert = SSL_get_peer_certificate(ssl);
CHK_NULL(server_cert);
printf ("Server certificate:/n");
str = X509_NAME_oneline(X509_get_subject_name(server_cert),0,0);
CHK_NULL(str);
printf ("t subject: %sn", str);
free (str);
str = X509_NAME_oneline (X509_get_issuer_name(server_cert),0,0);
CHK_NULL(str);
printf ("t issuer: %sn", str);
free (str);
X509_free(server_cert); /*如不需要,则将证书释放 */
/* 数据交换开始,用SSL_write,SSL_read代替write,read */
printf("Begin SSL data exchangen");
//发送消息
err =SSL_write(ssl,"Hello World!",strlen("Hello World!"));
CHK_SSL(err);
//接收消息
err = SSL_read (ssl, buf, sizeof(buf) - 1);
CHK_SSL(err);
buf[err] = '/0';
printf ("Got %d chars:'%s'n", err, buf);
SSL_shutdown (ssl); /* send SSL/TLS close_notify */
/* 收尾工作 */
shutdown (sd,2);
SSL_free (ssl);
SSL_CTX_free (ctx);
return 0;
}
/***************************************************************************************
*SSL/TLS服务端程序WIN32版(以demos/server.cpp为基础)
*需要用到动态连接库libeay32.dll,ssleay.dll,
*同时在setting中加入ws2_32.lib libeay32.lib ssleay32.lib,
*以上库文件在编译openssl后可在out32dll目录下找到,
*所需证书文件请参照<<利用Openssl生成证书文件>>自行生成
***************************************************************************************/
#include
#include
#include
#include
#include
#include
#include "openssl/rsa.h"
#include "openssl/crypto.h"
#include "openssl/x509.h"
#include "openssl/pem.h"
#include "openssl/ssl.h"
#include "openssl/err.h"
/*所有需要的参数信息都在此处以#define的形式提供*/
#define CERTF "server.crt" /*服务端的证书(需经CA签名)*/
#define KEYF "server.key" /*服务端的私钥(建议加密存储)*/
#define CACERT "ca.crt" /*CA 的证书*/
#define PORT 1111 /*准备绑定的端口*/
#define CHK_NULL(x) if ((x)==NULL) { exit (1); }
#define CHK_ERR(err,s) if ((err)==-1) { perror(s); exit(1); }
#define CHK_SSL(err) if ((err)==-1) { ERR_print_errors_fp(stderr); exit(2); }
int main ()
{
int err;
int listen_sd;
int sd;
struct sockaddr_in sa_serv;
struct sockaddr_in sa_cli;
int client_len;
SSL_CTX* ctx;
SSL* ssl;
X509* client_cert;
char* str;
char buf [4096];
SSL_METHOD *meth;
WSADATA wsaData;
if(WSAStartup(MAKEWORD(2,2),&wsaData) != 0)
{
printf("WSAStartup()fail:%dn",GetLastError());
return -1;
}
SSL_load_error_strings(); /*为打印调试信息作准备*/
OpenSSL_add_ssl_algorithms(); /*初始化,加载算法*/
meth = TLSv1_server_method(); /*采用什么协议(SSLv2/SSLv3/TLSv1)在此指定*/
ctx = SSL_CTX_new (meth);
CHK_NULL(ctx);
SSL_CTX_set_verify(ctx,SSL_VERIFY_PEER,NULL); /*验证与否*/
SSL_CTX_load_verify_locations(ctx,CACERT,NULL); /*若验证,则放置CA证书*/
//加载自己的证书文件
if(SSL_CTX_use_certificate_file(ctx,CERTF,SSL_FILETYPE_PEM) <= 0)
{
ERR_print_errors_fp(stderr);
exit(3);
}
//加载自己的密钥文件
if(SSL_CTX_use_PrivateKey_file(ctx, KEYF, SSL_FILETYPE_PEM) <= 0)
{
ERR_print_errors_fp(stderr);
exit(4);
}
//验证
if(!SSL_CTX_check_private_key(ctx))
{
printf("Private key does not match the certificate public key/n");
exit(5);
}
//选择安全通信协议
SSL_CTX_set_cipher_list(ctx,"RC4-MD5");
/*开始正常的TCP socket过程.................................*/
printf("Begin TCP socket.../n");
listen_sd = socket (AF_INET, SOCK_STREAM, 0);
CHK_ERR(listen_sd, "socket");
memset (&sa_serv, '/0', sizeof(sa_serv));
sa_serv.sin_family = AF_INET;
sa_serv.sin_addr.s_addr = INADDR_ANY;
sa_serv.sin_port = htons (PORT);
err = bind(listen_sd, (struct sockaddr*) &sa_serv,
sizeof (sa_serv));
CHK_ERR(err, "bind");
/*接受TCP链接*/
err = listen (listen_sd, 5);
CHK_ERR(err, "listen");
client_len = sizeof(sa_cli);
sd = accept (listen_sd, (struct sockaddr*) &sa_cli, &client_len);
CHK_ERR(sd, "accept");
closesocket (listen_sd);
printf ("Connection from %lx, port %x/n",
sa_cli.sin_addr.s_addr, sa_cli.sin_port);
/*TCP连接已建立,进行服务端的SSL过程...................... */
printf("Begin server side SSL/n");
ssl = SSL_new (ctx);
CHK_NULL(ssl);
SSL_set_fd (ssl, sd);
err = SSL_accept (ssl);
printf("SSL_accept finishedn");
CHK_SSL(err);
/*打印所有加密算法的信息(可选)*/
printf ("SSL connection using %s/n", SSL_get_cipher (ssl));
/*得到客户端的证书并打印些信息(可选) */
client_cert = SSL_get_peer_certificate (ssl);
if(client_cert != NULL)
{
printf ("Client certificate:/n");
str = X509_NAME_oneline(X509_get_subject_name (client_cert), 0, 0);
CHK_NULL(str);
printf ("t subject: %s/n", str);
free (str);
str = X509_NAME_oneline(X509_get_issuer_name (client_cert), 0, 0);
CHK_NULL(str);
printf ("t issuer: %s/n", str);
free (str);
X509_free (client_cert);/*如不需要,则将证书释放 */
}
else
{
printf ("Client does not have certificate./n");
}
/* 数据交换开始,用SSL_write,SSL_read代替write,read */
err = SSL_read (ssl, buf, sizeof(buf) - 1);
CHK_SSL(err);
buf[err] = '/0';
printf ("Got %d chars:'%s'/n", err, buf);
err = SSL_write (ssl, "I hear you.", strlen("I hear you."));
CHK_SSL(err);
/* 收尾工作*/
shutdown (sd,2);
SSL_free (ssl);
SSL_CTX_free (ctx);
return 0;
}
//OpenSSL库的下载,请查看<< OpenSSL库的编译与安装>>;
//利用OpenSSL库生成证书文件,请查看<< 利用OpenSSL生成证书文件>>.
//常用API<< 利用OpenSSL编写SSL通信程序时常使用的API>>.