A Usable, Secure Communications Protocol: Client-Side TLS - Implementing SSL/TLS Using Cryptography and PKI - page 302

Here, http_get and display_result change only slightly, as shown in Listing
6-3; they take an extra parameter indicating the new tls_context , and they call
tls_send and tls_recv to send and receive data; otherwise, they're identical to
the functions presented in Chapter 1:
Listing 6-3: “https.c” http_get and display_result
int http_get( int connection, const char *path, const char *host,
TLSParameters *tls_context )
{
static char get_command[ MAX_GET_COMMAND ];
sprintf( get_command, “GET /%s HTTP/1.1\r\n”, path );
if ( tls_send( connection, get_command,
strlen( get_command ), 0, tls_context ) == -1 )
{
return -1;
}
sprintf( get_command, “Host: %s\r\n”, host );
if ( tls_send( connection, get_command,
strlen( get_command ), 0, tls_context ) == -1 )
{
return -1;
}
strcpy( get_command, “Connection: Close\r\n\r\n” );
if ( tls_send( connection, get_command,
strlen( get_command ), 0, tls_context ) == -1 )
{
return -1;
}
return 0;
}
void display_result( int connection, TLSParameters *tls_context )
{
…
while ( ( received = tls_recv( connection, recv_buf,
BUFFER_SIZE, 0, tls_context ) ) >= 0 )
{
recv_buf[ received ] = '\0';
printf( “data: %s”, recv_buf );
}
…
Notice that the proxy negotiation part of http_get is missing from
Listing 6-3. Negotiating proxies is a major complication for SSL; by now you can
probably see why. The proxy performs the HTTP connection on behalf of the
client and then returns the results back to it. Unfortunately this is by defi nition a