static
int slip_receive_packet (char_slip_t *drv)
{
unsigned i, j, n;
unsigned char tmp[SLIP_BUF_MAX];
unsigned char *buf;
if (drv->tun_fd < 0) {
return (1);
}
if (tun_check_packet (drv->tun_fd) == 0) {
return (1);
}
n = SLIP_BUF_MAX;
if (tun_get_packet (drv->tun_fd, tmp, &n)) {
return (1);
}
buf = drv->inp;
j = 0;
buf[j++] = 192;
for (i = 0; i < n; i++) {
if (tmp[i] == 192) {
if (j < SLIP_BUF_MAX) {
buf[j++] = 219;
}
if (j < SLIP_BUF_MAX) {
buf[j++] = 220;
}
}
else if (tmp[i] == 219) {
if (j < SLIP_BUF_MAX) {
buf[j++] = 219;
}
if (j < SLIP_BUF_MAX) {
buf[j++] = 221;
}
}
else {
if (j < SLIP_BUF_MAX) {
buf[j++] = tmp[i];
}
}
}
if (j < SLIP_BUF_MAX) {
buf[j++] = 192;
}
drv->inp_idx = 0;
drv->inp_cnt = j;
return (0);
}
static
int slip_receive_packet (slip_t *slip)
{
#ifdef PCE_ENABLE_TUN
unsigned i, j, n;
unsigned char tmp[PCE_SLIP_BUF_MAX];
slip_buf_t *buf;
if (tun_check_packet (slip->tun_fd) == 0) {
return (1);
}
n = PCE_SLIP_BUF_MAX;
if (tun_get_packet (slip->tun_fd, tmp, &n)) {
return (1);
}
buf = slip_buf_alloc (slip);
if (buf == NULL) {
return (1);
}
j = 0;
buf->buf[j++] = 192;
for (i = 0; i < n; i++) {
if (tmp[i] == 192) {
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = 219;
}
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = 220;
}
}
else if (tmp[i] == 219) {
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = 219;
}
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = 221;
}
}
else {
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = tmp[i];
}
}
}
if (j < PCE_SLIP_BUF_MAX) {
buf->buf[j++] = 192;
}
#ifdef SLIP_DEBUG
fprintf (stderr, "slip: recv tun S=%u+%u Q=%u\n",
n, j - n, slip->inp_cnt + 1
);
#endif
buf->n = j;
if (slip->inp_hd == NULL) {
slip->inp_hd = buf;
}
else {
slip->inp_tl->next = buf;
}
slip->inp_tl = buf;
slip->inp_cnt += 1;
return (0);
#else
return (1);
#endif
}
int main(int c, char **v)
{
struct sockaddr_in server_addr, from;
socklen_t fromlen;
fd_set rfds;
struct tunnel_packet *tp;
char buf[MTU];
unsigned int buflen;
int ret;
int tun_fd;
int server_fd;
tp = (struct tunnel_packet *)buf;
if(c < 4) {
fprintf(stderr, "TCP/UDP/ICMP Tunnel over UDP\n"
"%s <hostname> <port> <passphrase>\n", v[0]);
return 0;
}
struct hostent* host_info = gethostbyname(v[1]);
if (host_info == NULL) {
fprintf(stderr, "%s: Invalid hostname or IPv4 address\n", v[1]);
return 1;
}
memset(&server_addr, 0, sizeof(server_addr));
memset(&from, 0, sizeof(from));
memcpy(&server_addr.sin_addr, host_info->h_addr, host_info->h_length);
if(strtoport(v[2], &server_addr.sin_port) == 0) {
fprintf(stderr, "%s: Invalid port\n", v[0]);
return 1;
}
server_addr.sin_family = AF_INET;
tun_fd = tun_create();
server_fd = socket_create(0);
/* Sending authentication */
tp->type = CONTROL_PACKET;
tp->cmd = AUTH_CMD;
strcpy(tp->data, PASSPHRASE);
socket_put_packet(server_fd, &server_addr, sizeof(server_addr), buf, sizeof(struct tunnel_packet) + strlen(PASSPHRASE));
/* Waiting acknowledge */
fromlen = sizeof(struct sockaddr_in);
buflen = socket_get_packet(server_fd, &from, &fromlen, buf, sizeof(buf));
if(tp->type == CONTROL_PACKET) {
if(tp->cmd != OK_CMD) {
puts("Password is incorret");
return 1;
}
} else {
puts("Unexpected packet was received.");
return 1;
}
#ifdef __linux__
exec_script("linux_client.sh", v[1]);
#else
exec_script("osx_client.sh", v[1]);
#endif
puts("+ Auth is OK.\n+ UDP Tunnel is running.");
FD_ZERO(&rfds);
while(1) {
FD_SET(server_fd, &rfds);
FD_SET(tun_fd, &rfds);
ret = select(server_fd+1, &rfds, NULL, NULL, NULL);
if(ret == -1)
break;
if(FD_ISSET(tun_fd, &rfds)) {
buflen = tun_get_packet(tun_fd, tp->data, sizeof(buf)-sizeof(struct tunnel_packet));
tp->type = TRAFFIC_PACKET;
tp->cmd = 0;
socket_put_packet(server_fd, &server_addr, sizeof(server_addr), buf, buflen + sizeof(struct tunnel_packet));
}
if(FD_ISSET(server_fd, &rfds)) {
buflen = socket_get_packet(server_fd, &from, &fromlen, buf, sizeof(buf));
if(server_addr.sin_addr.s_addr == from.sin_addr.s_addr && server_addr.sin_port == from.sin_port)
tun_put_packet(tun_fd, tp->data, buflen-sizeof(struct tunnel_packet));
}
}
return 1;
}
