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extern "C" {
#include <sys/types.h> // getaddrinfo, gai_strerror, socket, inet_pton
// connect
#include <sys/socket.h> // getaddrinfo, gai_strerror, socket, inet_pton
// connect
#include <unistd.h> // close
#include <netdb.h> // getaddrinfo, gai_strerror
#include <arpa/inet.h> // inet_pton
#include <sys/select.h> // select
#include <gnutls/gnutls.h>
}
#include <cstdio> // fprintf
#include <cerrno> // perror
#include <cstring> // memset
#define SOCKET_ERR(err,s) if(err<0) {perror(s);return(1);}
#define PORT 49001
#define CERTFILE "client-cert.pem"
#define KEYFILE "client-key.pem"
#define CAFILE "ca.pem"
gnutls_certificate_credentials_t x509_cred;
gnutls_session_t
initgnutls(){
gnutls_session_t session;
gnutls_global_init ();
/* X509 stuff */
gnutls_certificate_allocate_credentials (&x509_cred);
gnutls_certificate_set_x509_trust_file (x509_cred, CAFILE, GNUTLS_X509_FMT_PEM);
gnutls_certificate_set_x509_key_file (x509_cred, CERTFILE, KEYFILE,
GNUTLS_X509_FMT_PEM);
//Gnutls stuff
gnutls_init (&session, GNUTLS_CLIENT);
gnutls_set_default_priority (session);
gnutls_credentials_set (session, GNUTLS_CRD_CERTIFICATE, x509_cred);
return session;
}
int main (){
int sd, ret;
char buffer[512];
struct sockaddr_in6 to;
struct sockaddr_in6 from;
gnutls_session_t session;
fd_set rfds_orig;
struct timeval timeout;
session = initgnutls ();
sd = socket(PF_INET6, SOCK_DGRAM, 0);
SOCKET_ERR(sd,"socket");
{
int flag = 1;
ret = setsockopt(sd, SOL_SOCKET, SO_BROADCAST, & flag, sizeof(flag));
SOCKET_ERR(ret,"setsockopt broadcast");
}
setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, "eth0", 5);
SOCKET_ERR(ret,"setsockopt bindtodevice");
memset (&to, '\0', sizeof (to));
to.sin6_family = AF_INET6;
ret = inet_pton(AF_INET6, "ff02::1" , &to.sin6_addr);
SOCKET_ERR(ret,"setsockopt bindtodevice");
to.sin6_port = htons (PORT); // Server Port number
FD_ZERO(&rfds_orig);
FD_SET(sd, &rfds_orig);
timeout.tv_sec = 10;
timeout.tv_usec = 0;
for(;;){
sendto(sd, "Marco", 5, 0, reinterpret_cast<const sockaddr*>(&to), sizeof(to));
fd_set rfds = rfds_orig;
ret = select(sd+1, &rfds, 0, 0, & timeout);
SOCKET_ERR(sd,"select");
if (ret){
socklen_t from_len = sizeof(from);
ret = recvfrom(sd,buffer,512,0, reinterpret_cast<sockaddr *>(& from),
& from_len);
SOCKET_ERR(ret,"recv");
if (strncmp(buffer,"Polo", 4) == 0){
break;
}
}
}
write(1,buffer,ret);
write(1,"\n",1);
//shutdown procedure
close(sd);
sleep(1);
sd = socket(PF_INET6, SOCK_STREAM, 0);
SOCKET_ERR(sd,"socket");
setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, "eth0", 5);
SOCKET_ERR(ret,"setsockopt bindtodevice");
memset(&to,0,sizeof(to));
to.sin6_family = from.sin6_family;
to.sin6_port = from.sin6_port;
to.sin6_addr = from.sin6_addr;
to.sin6_scope_id = from.sin6_scope_id;
ret = connect(sd,reinterpret_cast<struct sockaddr *>(&to),sizeof(to));
SOCKET_ERR(ret,"connect");
gnutls_transport_set_ptr (session, reinterpret_cast<gnutls_transport_ptr_t> (sd));
ret = gnutls_handshake (session);
if (ret < 0)
{
fprintf (stderr, "*** Handshake failed\n");
gnutls_perror (ret);
return 1;
}
printf ("- Handshake was completed\n");
//message to be seent
gnutls_record_send (session, "The secret message is \"squeamish ossifrage\"\n", 44);
//shutdown procedure
gnutls_bye (session, GNUTLS_SHUT_RDWR);
close(sd);
gnutls_deinit (session);
gnutls_certificate_free_credentials (x509_cred);
gnutls_global_deinit ();
close(sd);
return 0;
}
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