[Network programming] Win32 Socket + OpenSSL instance

OpenSSL

OpenSSL is not just SSL. It can implement message digest, file encryption and decryption, digital certificates, digital signatures and random numbers. There are a lot of content about the OpenSSL library, which is far from an article.

OpenSSL is not just an API, but also a command line tool. The command line tool can do the same work as the API, and further test the SSL server and client.

Server coding process source code: Create a win32 Empty Project SSL_Server

// SSL_Server.cpp # include <iostream> # include <winsock2.h> # include <openssl/rsa. h>/* SSLeay stuff */# include <openssl/crypto. h> # include <openssl/x509.h> # include <openssl/pem. h> # include <openssl/ssl. h> # include <openssl/err. h> // # privatekey. pem // cmd :.. \ openssl-1.0.1e \ bin> openssl genrsa-out privatekey. pem 2048 -- an empty password is generated // # cacert. pem // cmd :.. \ openssl-1.0.1e \ bin> openssl req-new-x509-key private Key. pem-out cacert. pem-days 1095-config .. \ ssl \ openssl. cnf # define CACERT "E: \ ReferData \ OpenSSL \ openssl-1.0.1e \ bin \ cacert. pem "# define PRIKEY" E: \ ReferData \ OpenSSL \ openssl-1.0.1e \ bin \ privatekey. pem "# define PRIKEY_CODE" women123 "// ---- be consistent with the generated key # define MAXBUF 1024 # define DEFPORT 7838 # pragma comment (lib," ws2_32.lib ") # pragma comment (lib, lib, "libeay32.lib") # pragma comment (lib, "ssleay3 2. lib ") ************************ * ********************* filename: ssl-server.c * purpose: demonstrate how to use the OpenSSL library for IP layer-based SSL encrypted communication, this is a server-side example * wrote by: zhoulifa (zhoulifa@163.com) Weekly release (http://zhoulifa.bokee.com) linux enthusiast Linux knowledge transmitter sohou developers are best at C Language * date time: * Note: Anyone can copy code and use these documents at will, of course, it includes your commercial use * but follow GPL * Thanks to: Google * Hope: more and more people are expected to contribute their own strength, contribute to the development of science and technology * technological progress is faster on the shoulders of giants! Thank you for your contributions to the open source team! **************************************** * ***************************/Int main () {int sockfd, new_fd; int len; struct sockaddr_in my_addr, their_addr; char buf [MAXBUF + 1]; SSL_CTX * ctx; SSL_library_init (); /* initialize the SSL library */OpenSSL_add_all_algorithms ();/* load all SSL algorithms */SSL_load_error_strings (); /* load all SSL error messages */ctx = SSL_CTX_new (SSLv23_server_method ();/* generate an SSL_CTX in the standard SSL V2 and V3 compatibility mode, that is, SSL C Ontent Text * // * You can also use SSLv2_server_method () or SSLv3_server_method () to separately represent V2 or V3 standard */if (ctx = NULL) {ERR_print_errors_fp (stdout ); exit (1);} if (SSL_CTX_use_certificate_file (ctx, CACERT, SSL_FILETYPE_PEM) <= 0)/* load your digital certificate, which is sent to the client. The certificate contains the Public Key */{ERR_print_errors_fp (stdout); exit (1);} // SSL_CTX_set_default_passwd_cb_userdata (ctx, PRIKEY_CODE); // if it is not an empty private file, without this line of code, "EnterPEM pess phrass:" will appear --- enter the password if (SSL_CTX_use_PrivateKey_file (ctx, PRIKEY, SSL_FILETYPE_PEM) <= 0) /* load the user's private key */{ERR_print_errors_fp (stdout); exit (1);} if (! SSL_CTX_check_private_key (ctx)/* check whether the user's private key is correct */{ERR_print_errors_fp (stdout); exit (1);} WSADATA wsaData; int ret = WSAStartup (MAKEWORD (2, 2), & wsaData); if (ret! = 0) {std: cout <"WSAStartup error. "<std: endl; return-1;}/* enable a socket listener */if (sockfd = socket (PF_INET, SOCK_STREAM, 0) =-1) {perror ("socket"); exit (1);} else printf ("socket created \ n"); memset (& my_addr, 0, sizeof (my_addr )); my_addr.sin_family = PF_INET; my_addr.sin_port = htons (DEFPORT); region = INADDR_ANY; if (bind (sockfd, (struct sockaddr *) & my_addr, sizeof (struct) Sockaddr) =-1) {perror ("bind"); exit (1);} else printf ("binded \ n"); if (listen (sockfd, 2) =-1) {perror ("listen"); exit (1);} else printf ("begin listen \ n"); while (1) {SSL * ssl; len = sizeof (struct sockaddr);/* Wait for the client to connect */if (new_fd = accept (sockfd, (struct sockaddr *) & their_addr, & len )) =-1) {perror ("accept"); exit (errno);} else printf ("server: got connection from % s, port % d, socket % D \ n ", inet_ntoa (secure), ntohs (their_addr.sin_port), new_fd); ssl = SSL_new (ctx);/* generate a new SSL */SSL_set_fd (ssl, new_fd);/* Add the socket of the connected user to SSL */if (SSL_accept (ssl) =-1) /* establish an SSL connection */{perror ("accept"); closesocket (new_fd); break;}/* start to process the data sending and receiving of each new connection */memset (buf, 0, MAXBUF + 1); strcpy (buf, "server-> client");/* send a message to the client */len = SSL_write (ssl, buf, strlen (buf )); if (le N <= 0) {printf ("message '% s' failed to be sent! Error code: % d, error message: '% s' \ n ", buf, errno, strerror (errno); goto finish ;} else printf ("message '% s' is successfully sent. % d bytes are sent in total! \ N ", buf, len); memset (buf, 0, MAXBUF + 1);/* receive client messages */len = SSL_read (ssl, buf, MAXBUF ); if (len> 0) printf ("Message received successfully: '% s', % d bytes of data \ n", buf, len ); else printf ("message receiving failed! Error code: % d, error message: '% s' \ n ", errno, strerror (errno); finish: /* process the data sent and received by each new connection */SSL_shutdown (ssl);/* close the SSL connection */SSL_free (ssl);/* release SSL */closesocket (new_fd ); /* close socket */} closesocket (sockfd);/* close the socket */SSL_CTX_free (ctx);/* release CTX */return 0 ;}

Client coding process source code: Create a win32 Empty Project SSL_Client

// SSL_Client.cpp # include <iostream> # include <winsock2.h> # include <openssl/rsa. h>/* SSLeay stuff */# include <openssl/crypto. h> # include <openssl/x509.h> # include <openssl/pem. h> # include <openssl/ssl. h> # include <openssl/err. h> # pragma comment (lib, "ws2_32.lib") # pragma comment (lib, "libeay32.lib") # pragma comment (lib, "ssleay32.lib ") # define MAXBUF 1024 # define DEF_IP "127.0.0.1" # define DEF_PORT 78 38 void ShowCerts (SSL * ssl) {X509 * cert; char * line; cert = SSL_get_peer_certificate (ssl); if (cert! = NULL) {printf ("Digital Certificate Information: \ n"); line = X509_NAME_oneline (X509_get_subject_name (cert), 0, 0); printf ("certificate: % s \ n ", line); OPENSSL_free (line); line = X509_NAME_oneline (X509_get_issuer_name (cert), 0, 0); printf (" issuer: % s \ n ", line); OPENSSL_free (line); X509_free (cert);} else printf ("no certificate information! \ N ");} ************************ * ********************* filename: ssl-client.c * purpose: demonstrate how to use the OpenSSL library for IP layer-based SSL encrypted communication, this is a client example * wrote by: zhoulifa (zhoulifa@163.com) Weekly release (http://zhoulifa.bokee.com) linux enthusiast Linux knowledge transmitter sohou developers are best at C Language * date time: * Note: Anyone can copy code and use these documents at will, of course, it includes your commercial use * but follow GPL * Thanks to: Google * Hope: more and more people are expected to contribute their own strength, contribute to the development of science and technology * technological progress is faster on the shoulders of giants! Thank you for your contributions to the open source team! **************************************** * ***************************/Int main () {int sockfd, len; struct sockaddr_in dest; char buffer [MAXBUF + 1]; SSL_CTX * ctx; SSL * ssl;/* SSL library initialization, see the ssl-server.c Code */SSL_library_init (); sums (); SSL_load_error_strings (); ctx = SSL_CTX_new (SSLv23_client_method (); if (ctx = NULL) {sums (stdout ); exit (1);} WSADATA wsaData; I Nt ret = WSAStartup (MAKEWORD (2, 2), & wsaData); if (ret! = 0) {std: cout <"WSAStartup error. "<std: endl; return-1;}/* Create a socket for tcp communication */if (sockfd = socket (AF_INET, SOCK_STREAM, 0) <0) {perror ("Socket"); exit (errno);} printf ("socket created \ n");/* initialize the server (PEER) /memset (& dest, 0, sizeof (dest); dest. sin_family = AF_INET; dest. sin_addr.S_un.S_addr = inet_addr (DEF_IP); dest. sin_port = htons (DEF_PORT); printf ("address created \ n");/* connection Server */if (connect (sockfd, (struct sockaddr *) & dest, sizeof (dest ))! = 0) {perror ("Connect"); exit (errno);} printf ("server connected \ n "); /* generate a new SSL */ssl = SSL_new (ctx) based on ctx; SSL_set_fd (ssl, sockfd);/* establish an SSL connection */if (SSL_connect (ssl) =-1) ERR_print_errors_fp (stderr); else {printf ("Connected with % s encryption \ n", SSL_get_cipher (ssl); ShowCerts (ssl );} /* receive messages sent from the other party. A maximum of MAXBUF bytes */memset (buffer, 0, MAXBUF + 1) can be received ); /* receive messages from the server */len = SSL_read (ssl, B Uffer, MAXBUF); if (len> 0) printf ("Message received successfully: '% s', % d bytes of data \ n", buffer, len ); else {printf ("message receiving failed! Error code: % d, error message: '% s' \ n ", errno, strerror (errno); goto finish;} memset (buffer, 0, MAXBUF + 1 ); strcpy (buffer, "from client-> server");/* send a message to the server */len = SSL_write (ssl, buffer, strlen (buffer); if (len <0) printf ("message '% s' failed to be sent! Error code: % d, error message: '% s' \ n ", buffer, errno, strerror (errno); else printf (" message' % s' is sent successfully, % d bytes are sent! \ N ", buffer, len); finish:/* close connection */SSL_shutdown (ssl); SSL_free (ssl); closesocket (sockfd); SSL_CTX_free (ctx ); system ("pause"); return 0 ;}

Refer to blog:

Linux Network Programming step by step-encrypted communication protocol SSL research using key digital certificate OpenSSL in openssl System