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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, STDIN_FILENO, STDOUT_FILENO
#include <netdb.h> // getaddrinfo, gai_strerror
#include <arpa/inet.h> // inet_pton
#include <sys/select.h> // select
#include <gnutls/gnutls.h>
#include <sys/ioctl.h> // ioctl, ifreq, SIOCGIFFLAGS, IFF_UP, SIOCSIFFLAGS
#include <net/if.h> // ioctl, ifreq, SIOCGIFFLAGS, IFF_UP, SIOCSIFFLAGS
#include <termios.h> // struct termios, tcsetattr, tcgetattr, TCSAFLUSH, ECHO
}
#include <cerrno> // perror
#include <cstring> // memset
#include <string> // std::string, std::getline
#include <iostream> // cin, cout, cerr
#include <ostream> // <<
#define SOCKET_ERR(err,s) if(err<0) {perror(s); status = 1; goto quit;}
#define PORT 49001
#define CERTFILE "/conf/conf.d/cryptkeyreq/client-cert.pem"
#define KEYFILE "/conf/conf.d/cryptkeyreq/client-key.pem"
#define CAFILE "/conf/conf.d/cryptkeyreq/ca.pem"
gnutls_certificate_credentials_t x509_cred;
gnutls_session_t
initgnutls(){
gnutls_session_t session;
#ifdef DEBUG
std::cerr << "Initiate certificates\n";
#endif
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 udp_sd, tcp_sd, ret;
char buffer[4096];
struct sockaddr_in6 to;
struct sockaddr_in6 from;
gnutls_session_t session;
fd_set rfds_orig;
struct timeval timeout;
struct termios t_old, t_new;
int status = 0;
session = initgnutls ();
#ifdef DEBUG
std::cerr << "Open ipv6 UDP\n";
#endif
udp_sd = socket(PF_INET6, SOCK_DGRAM, 0);
SOCKET_ERR(udp_sd,"socket");
#ifdef DEBUG
std::cerr << "Open socket with socket nr: " << udp_sd << '\n';
#endif
{
int flag = 1;
ret = setsockopt(udp_sd, SOL_SOCKET, SO_BROADCAST, & flag, sizeof(flag));
SOCKET_ERR(ret,"setsockopt broadcast");
}
ret = setsockopt(udp_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,"inet_pton");
to.sin6_port = htons (PORT); // Server Port number
struct ifreq network;
strcpy(network.ifr_name, "eth0");
ret = ioctl(udp_sd, SIOCGIFFLAGS, &network);
SOCKET_ERR(ret,"ioctl SIOCGIFFLAGS");
network.ifr_flags |= IFF_UP;
ret = ioctl(udp_sd, SIOCSIFFLAGS, &network);
SOCKET_ERR(ret,"ioctl SIOCSIFFLAGS");
FD_ZERO(&rfds_orig);
FD_SET(udp_sd, &rfds_orig);
FD_SET(STDIN_FILENO, &rfds_orig);
if (tcgetattr (STDIN_FILENO, &t_old) != 0){
return 1;
}
t_new = t_old;
t_new.c_lflag &= ~ECHO;
if (tcsetattr (STDIN_FILENO, TCSAFLUSH, &t_new) != 0){
return 1;
}
for(;;){
for(;;){
#ifdef DEBUG
std::cerr << "Sending Marco on UDP\n";
#endif
ret = sendto(udp_sd, "Marco", 5, 0, reinterpret_cast<const sockaddr*>(&to), sizeof(to));
if (ret < 0){
perror("sendto");
}
fd_set rfds = rfds_orig;
timeout.tv_sec = 10;
timeout.tv_usec = 0;
std::cerr << "Password: ";
ret = select(udp_sd+1, &rfds, 0, 0, & timeout);
SOCKET_ERR(udp_sd,"select");
if (ret){
if (FD_ISSET(STDIN_FILENO, &rfds)){
std::string buffer;
std::getline(std::cin, buffer);
std::cerr << '\n';
std::cout << buffer;
goto quit;
}
socklen_t from_len = sizeof(from);
ret = recvfrom(udp_sd,buffer,512,0, reinterpret_cast<sockaddr *>(& from),
& from_len);
SOCKET_ERR(ret,"recv");
if (strncmp(buffer,"Polo", 4) == 0){
break;
}
}
std::cerr << '\r';
}
tcp_sd = socket(PF_INET6, SOCK_STREAM, 0);
SOCKET_ERR(tcp_sd,"socket");
setsockopt(tcp_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(tcp_sd,reinterpret_cast<struct sockaddr *>(&to),sizeof(to));
if (ret < 0){
perror("connect");
continue;
}
gnutls_transport_set_ptr (session, reinterpret_cast<gnutls_transport_ptr_t> (tcp_sd));
ret = gnutls_handshake (session);
if (ret < 0)
{
std::cerr << "\n*** Handshake failed ***\n";
gnutls_perror (ret);
continue;
}
//retrive password
ret = gnutls_record_recv (session, buffer, sizeof(buffer));
write(STDOUT_FILENO,buffer,ret);
//shutdown procedure
gnutls_bye (session, GNUTLS_SHUT_RDWR);
close(tcp_sd);
gnutls_deinit (session);
gnutls_certificate_free_credentials (x509_cred);
gnutls_global_deinit ();
break;
}
close(udp_sd);
quit:
tcsetattr (STDIN_FILENO, TCSAFLUSH, &t_old);
return status;
}
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