static int internal_init_mcrypt(MCRYPT td, const void *key, int lenofkey, const void *IV)
{
int *sizes = NULL;
int num_of_sizes, i, ok = 0;
int key_size = mcrypt_enc_get_key_size(td);
if (lenofkey > key_size || lenofkey==0) {
return MCRYPT_KEY_LEN_ERROR; /* error */
}
sizes = mcrypt_enc_get_supported_key_sizes(td, &num_of_sizes);
if (sizes != NULL) {
for (i = 0; i < num_of_sizes; i++) {
if (lenofkey == sizes[i]) {
ok = 1;
break;
}
}
} else { /* sizes==NULL */
if (num_of_sizes == 0
&& lenofkey <= mcrypt_enc_get_key_size(td))
ok = 1;
}
if (ok == 0) { /* not supported key size */
key_size = mcrypt_enc_get_key_size(td);
if (sizes != NULL) {
for (i = 0; i < num_of_sizes; i++) {
if (lenofkey <= sizes[i]) {
key_size = sizes[i];
break;
}
}
} else { /* well every key size is supported! */
key_size = lenofkey;
}
} else {
key_size = lenofkey;
}
free(sizes);
td->keyword_given = mxcalloc(1, mcrypt_enc_get_key_size(td));
if (td->keyword_given==NULL) return MCRYPT_MEMORY_ALLOCATION_ERROR;
memmove(td->keyword_given, key, lenofkey);
i = mcrypt_get_size(td);
td->akey = mxcalloc(1, i);
if (td->akey==NULL) {
free(td->keyword_given);
return MCRYPT_MEMORY_ALLOCATION_ERROR;
}
i = mcrypt_mode_get_size(td);
if (i > 0) {
td->abuf = mxcalloc(1, i);
if (td->abuf==NULL) {
free(td->keyword_given);
free(td->akey);
return MCRYPT_MEMORY_ALLOCATION_ERROR;
}
}
ok = init_mcrypt(td, td->abuf, key, key_size, IV);
if (ok!=0) {
free(td->keyword_given);
free(td->akey);
free(td->abuf);
return MCRYPT_UNKNOWN_ERROR; /* algorithm error */
}
ok = mcrypt_set_key(td,
(void *) td->akey,
(void *) td->keyword_given,
key_size, IV, IV!=NULL ? mcrypt_enc_get_iv_size(td) : 0);
if (ok!=0) {
internal_end_mcrypt(td);
return MCRYPT_UNKNOWN_ERROR; /* algorithm error */
}
return 0;
}
int main(int argc, char *argv[]) {
init_new_term();
/*-------- Get options ---------------------*/
int option;
int option_index;
static struct option long_options[] = {
{"log", required_argument, NULL, 'l'},
{"encrypt", no_argument, NULL, 'e'},
{"port", required_argument, NULL, 'p'}
};
while((option = getopt_long(argc, argv, "", long_options, &option_index)) != EOF)
switch(option) {
case 'p':
port_no = *((int *)optarg);
break;
case 'l':
log_on = true;
if((log_fd = dup(open(optarg, O_CREAT|O_TRUNC|O_WRONLY, 0644))) == ERROR) {
fprintf(stderr, "Error: %s\n", strerror(errno));
exit(RC=EXIT_FAILURE);
}
break;
case 'e':
encrypt_on = true;
break;
}
/*--------- Setup client --------------------*/
if((socket_fd = socket(AF_INET, SOCK_STREAM, 0)) == ERROR) {
fprintf(stderr, "Error: could not create server_socket_fd.\n");
}
/*--------- Setup server client will be connecting to ----------*/
server_addr.sin_addr.s_addr = inet_addr(LOCALHOST);
server_addr.sin_family = AF_INET;
server_addr.sin_port = htons(port_no);
/*--------- Connecting to server --------------*/
fprintf(stdout, "Waiting to connect to server...\n");
if(connect(socket_fd, (struct sockaddr *)&server_addr, sizeof(server_addr)) == ERROR) {
fprintf(stderr, "Error: could not connect to server.\n");
exit(RC=EXIT_FAILURE);
}
fprintf(stdout, "Connected to %s on port %d!\n", LOCALHOST, port_no);
/*--------- Process server output ---------------*/
pthread_t process_server_thread;
pthread_create(&process_server_thread, NULL, &process_server_output, &socket_fd);
/*--------- Initialize mcrypt -------------------*/
if(encrypt_on)
init_mcrypt();
/*--------- Get input from terminal -------------*/
char buffer;
while(1) {
// Read error
if(read(STDIN_FILENO, &buffer, NREAD) == 0) {
fprintf(stderr, "Error: could not read c from stdin.\n");
close(socket_fd);
exit(RC=RECEIVED_EOF_READERROR);
}
// buffer == ^D
if(buffer == EOT) {
fprintf(stdout, "Recieved ^D.\n");
close(socket_fd);
exit(RC=RECEIVED_D);
}
/*--- Map <cr> or <lf> to <cr><lf> ------*/
else if(buffer == CR || buffer == LF) {
// Echo to stdout
if(write(STDOUT_FILENO, &CR, 1) != 1) {
fprintf(stderr, "Error: could not write <cr> to stdout.\n");
exit(RC=EXIT_FAILURE);
}
if(write(STDOUT_FILENO, &LF, 1) != 1) {
fprintf(stderr, "Error: could not write <lf> to stdout.\n");
exit(RC=EXIT_FAILURE);
}
/*--- Write <cr><lf>, <cr>, <lf> to server as <lf> ---*/
buffer = LF;
// Encrypt
if(encrypt_on && mcrypt_generic(td, &buffer, NREAD) != 0) {
fprintf(stderr, "Error: encryption to write to server failed.\n");
exit(RC=EXIT_FAILURE);
}
// Write to server
if(write(socket_fd, &buffer, 1) != 1) {
fprintf(stderr, "Error: could not write <lf> to server.\n");
exit(RC=EXIT_FAILURE);
}
}
// All other characters
else {
// Echo to stdout
if(write(STDOUT_FILENO, &buffer, NREAD) != NREAD) {
fprintf(stderr, "Error: could not write buffer to stdout.\n");
exit(RC=EXIT_FAILURE);
}
// Encrypt
if(encrypt_on && mcrypt_generic(td, &buffer, NREAD) != 0) {
fprintf(stderr, "Error: encryption to write to server failed.\n");
exit(RC=EXIT_FAILURE);
}
// Write to server
if(write(socket_fd, &buffer, NREAD) != NREAD) {
fprintf(stderr, "Error: could not write buffer to server.\n");
exit(RC=EXIT_FAILURE);
}
}
// Write to log
if(log_on) {
write(log_fd, &LOG_SENT_PREFIX, SENT_PREFIX_LENGTH);
write(log_fd, &buffer, NREAD);
write(log_fd, &LF, 1);
}
}
exit(RC=EXIT_SUCCESS);
}
