Small correction - the return type error came with the default file - with
void main. Now, only this error on compilation
[swu...@mpvmpc19 ssl]$ g++ -lssl -lcrypto cli.cpp
cli.cpp: In function `int main()':
cli.cpp:106: error: `close' was not declared in this scope
[swu...@mpvmpc19 ssl]$ vi cli.cpp
On Tue, May 12, 2009 at 3:11 PM, mail man <mailman.inter...@gmail.com>wrote:
> Hi experts,
>
> I am completely new to encrytion / ssl.
> I am trying to compile the demos from /openssl-0.9.8j/demos/ssl on CentOS
> 4.5
>
> My objective is to setup a client and server using ssl to ensure secure
> communication :). Needless to say I am getting a lot of errors:
>
> [swu...@mpvmpc19 ssl]$ g++ -lssl -lcrypto cli.cpp (got this command from
> perusing archives from the list, don't know if right oe not)
> cli.cpp:29: error: `main' must return `int'
> cli.cpp: In function `int main(...)':
> cli.cpp:106: error: `close' was not declared in this scope
>
>
> In cli.cpp, main has return type int, with a return 0 down below.
> Here is cli.cpp:
>
> [swu...@mpvmpc19 ssl]$ cat cli.cpp
>> /* cli.cpp - Minimal ssleay client for Unix
>> 30.9.1996, Sampo Kellomaki <sa...@iki.fi> */
>>
>> /* mangled to work with SSLeay-0.9.0b and OpenSSL 0.9.2b
>> Simplified to be even more minimal
>> 12/98 - 4/99 Wade Scholine <wa...@mail.cybg.com> */
>>
>> #include <stdio.h>
>> #include <memory.h>
>> #include <errno.h>
>> #include <sys/types.h>
>> #include <sys/socket.h>
>> #include <netinet/in.h>
>> #include <arpa/inet.h>
>> #include <netdb.h>
>>
>> #include <openssl/crypto.h>
>> #include <openssl/x509.h>
>> #include <openssl/pem.h>
>> #include <openssl/ssl.h>
>> #include <openssl/err.h>
>>
>>
>> #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 sd;
>> struct sockaddr_in sa;
>> SSL_CTX* ctx;
>> SSL* ssl;
>> X509* server_cert;
>> char* str;
>> char buf [4096];
>> SSL_METHOD *meth;
>>
>> SSLeay_add_ssl_algorithms();
>> meth = SSLv2_client_method();
>> SSL_load_error_strings();
>> ctx = SSL_CTX_new (meth); CHK_NULL(ctx);
>>
>> CHK_SSL(err);
>>
>> /* ----------------------------------------------- */
>> /* Create a socket and connect to server using normal socket calls. */
>>
>> 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 ("127.0.0.1"); /* Server IP */
>> sa.sin_port = htons (1111); /* Server Port number */
>>
>> err = connect(sd, (struct sockaddr*) &sa,
>> sizeof(sa)); CHK_ERR(err, "connect");
>>
>> /* ----------------------------------------------- */
>> /* Now we have TCP conncetion. Start SSL negotiation. */
>>
>> ssl = SSL_new (ctx); CHK_NULL(ssl);
>> SSL_set_fd (ssl, sd);
>> err = SSL_connect (ssl); CHK_SSL(err);
>>
>> /* Following two steps are optional and not required for
>> data exchange to be successful. */
>>
>> /* Get the cipher - opt */
>>
>> printf ("SSL connection using %s\n", SSL_get_cipher (ssl));
>>
>> /* Get server's certificate (note: beware of dynamic allocation) - opt
>> */
>>
>> 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: %s\n", str);
>> OPENSSL_free (str);
>>
>> str = X509_NAME_oneline (X509_get_issuer_name (server_cert),0,0);
>> CHK_NULL(str);
>> printf ("\t issuer: %s\n", str);
>> OPENSSL_free (str);
>>
>> /* We could do all sorts of certificate verification stuff here before
>> deallocating the certificate. */
>>
>> X509_free (server_cert);
>>
>> /* --------------------------------------------------- */
>> /* DATA EXCHANGE - Send a message and receive a reply. */
>>
>> err = SSL_write (ssl, "Hello World!", strlen("Hello World!"));
>> CHK_SSL(err);
>>
>> 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 */
>>
>> /* Clean up. */
>>
>> close (sd);
>> SSL_free (ssl);
>> SSL_CTX_free (ctx);
>> return 0;
>> }
>> /* EOF - cli.cpp */
>>
>>
>
> Please tell me what the problem could be.
>
> Many thanks,
> mailman
>
