static inline void gen_next_kappa(unsigned char* nonce, const AES_KEY kappa_0[1], AES_KEY kappa[1], const AES_KEY key[1]){
int i;
inc_nonce(nonce);
gen_kappa(nonce,kappa,key);
/* We make the xor with kappa 0 here, so we don't need to do it with every block*/
for(i=0; i < 4; i++)
kappa[0].ks[i] ^= kappa_0[0].ks[i];
}
int main(){
int s,b,on=1,i;
struct sockaddr_in channel, server;
unsigned char buf[BUF_SIZE];
unsigned char k[crypto_secretbox_KEYBYTES];
unsigned char n[crypto_secretbox_NONCEBYTES];
unsigned char m[BUF_SIZE]; unsigned long long mlen = BUF_SIZE;
unsigned char c[BUF_SIZE];
/* Address structure */
memset(&channel,0,sizeof(channel));
channel.sin_family = AF_INET;
channel.sin_addr.s_addr = htonl(INADDR_ANY);
channel.sin_port = htons(CLIENT_PORT);
/* Build socket and Bind */
s = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); /* Create socket */
if(s<0)
fatal("Failed to create socket!");
setsockopt(s,SOL_SOCKET,SO_REUSEADDR,(char*)&on,sizeof(on)); //Osäker på denna
b = bind(s,(struct sockaddr *)&channel,sizeof(channel));
if(b<0){
fatal("Bind failed ");
}
//Setting up server address
memset(&server,0,sizeof(server));
server.sin_family = AF_INET;
server.sin_addr.s_addr = htonl(INADDR_LOOPBACK); //INADDR_LOOPBACK är denna datorns ip i.e 127.0.0.1 //inet_addr(serverIP); <- får användas över nätverk där serverIP ges som klassisk xxx.xxx.xxx.xxx
server.sin_port = htons(SERVER_PORT); //Serverns portnummer
/* Time to start sending */
if(connect(s,(struct sockaddr *)&server,sizeof(server))){
fatal("Could not connect to server");
}
//usleep(1000); //Ska tydligen ge server tid fast det funkar utan detta, iallafall när localhost-localhost
// Här börjar diffie-hellman *************************************************************************
if(!dh(k,crypto_secretbox_KEYBYTES,n,crypto_secretbox_NONCEBYTES,s)){
fatal("Diffie-hellman fail!");
}
// S**t på diffie-hellman *********************************************************
// Här Börjar symetrisk krytering *************************************************
while(1){ //Infinite message chain loop
for(i=0;i<BUF_SIZE;i++){ //Reset message
m[i] = 0;
}
i = crypto_secretbox_ZEROBYTES; //Begin message at byte 32
printf("\nWrite your message(q/Q to quit):\n");
fgets((char *)&m[i],200,stdin); // Get message from user max 200 charachters (should be enough)
if((m[i] =='q' || m[i] == 'Q') && strlen((char *)&m[i]) == 2){
break;
}
if(VISIBLE){
printf("\n\n****** Symmetric encryption/decryption echo begin ******\n\n");
printf("\nClient plaintext:\n%s\n",&m[i]);
}
if(crypto_secretbox(c,m,mlen,n,k)!=0){
fatal("Cryptobox fail!");
}
inc_nonce(n);
if(VISIBLE){
printf("\nClient ciphertext:\n%s\n",&c[crypto_secretbox_ZEROBYTES]); //Kolla om detta borde stämma
}
if(write(s,c,BUF_SIZE)==-1){ // Skriver meddelandet till server. _!check!_ check funkar ej pröva annat (send)!
fatal("Server not responding");
}
for(i=0;i<BUF_SIZE;i++){
buf[i] = 0;
}
read(s,c,BUF_SIZE); // Läser in svar _!check!_
if(VISIBLE){
printf("\nServer ciphertext:\n%s\n",&c[crypto_secretbox_ZEROBYTES]);
}
if(crypto_secretbox_open(buf,c,BUF_SIZE,n,k)==-1){
fatal("Decryption fail!");
}
inc_nonce(n);
if(VISIBLE){
printf("\nServer plaintext:\n%s\n",&buf[crypto_secretbox_ZEROBYTES]);
printf("\n\n****** Symmetric encrytion/decryption echo end ******\n\n");
}
printf("\n\n");
printf("Server says: %s\n", &buf[32]);
}
close(s);
printf("Exiting program!\n");
return 0;
}
