2.cpp

X.509de yingyong 和开发的.具体可以先学习一下.openssl的相关知识

#include <stdio.h>
#include <stdlib.h>
#include <memory.h>
#include <errno.h>
#include <sys/types.h>

#include <winsock2.h>

#include "openssl/rsa.h"
#include "openssl/crypto.h"
#include "openssl/x509.h"
#include "openssl/pem.h"
#include "openssl/ssl.h"
#include "openssl/err.h"

#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:d\n",GetLastError());
return -1;
}

SSL_load_error_strings();/*为打印调试信息作准备*/
OpenSSL_add_ssl_algorithms();/*初始化*/
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*/

if (SSL_CTX_use_certificate_file(ctx, CERTF, SSL_FILETYPE_PEM) <= 0) {
ERR_print_errors_fp(stderr);
exit(3);
}
if (SSL_CTX_use_PrivateKey_file(ctx, KEYF, SSL_FILETYPE_PEM) <= 0) {
ERR_print_errors_fp(stderr);
exit(4);
}

if (!SSL_CTX_check_private_key(ctx)) {
printf("Private key does not match the certificate public key\n");
exit(5);
}

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 finished\n");
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));

/*得到服务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);/*如不再需要,需将证书释放 */
}
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;
}