void SV_initServer(int maxConnections, unsigned short port, socketProtocol_t protocol, networkStatus_t *status)
{
if (currentNetworkMode() != NETWORK_MODE_LOCAL)
{
if (status)
{
status->error = NETWORK_ERROR_UNAUTHORIZED_ACTION;
status->socketError = 0;
}
return;
}
if (!createHostSocket(maxConnections, port, protocol, status))
{
return;
}
if (status)
{
status->error = NETWORK_ERROR_NONE;
status->socketError = 0;
}
}
int pptp_manager(int argc, char **argv)
{
int firstOpen = -1;
int ctrl_pid;
socklen_t addrsize;
int hostSocket;
fd_set connSet;
int rc, sig_fd;
rc = sigpipe_create();
if (rc < 0) {
syslog(LOG_ERR, "MGR: unable to setup sigchld pipe!");
syslog_perror("sigpipe_create");
exit(-1);
}
sigpipe_assign(SIGCHLD);
sigpipe_assign(SIGTERM);
sig_fd = sigpipe_fd();
/* openlog() not required, done in pptpd.c */
syslog(LOG_INFO, "MGR: Manager process started");
if (!pptp_delegate) {
syslog(LOG_INFO, "MGR: Maximum of %d connections available",
pptp_connections);
}
/* Connect the host socket and activate it for listening */
if (createHostSocket(&hostSocket) < 0) {
syslog(LOG_ERR, "MGR: Couldn't create host socket");
syslog_perror("createHostSocket");
exit(-1);
}
while (1) {
int max_fd;
FD_ZERO(&connSet);
if (pptp_delegate) {
FD_SET(hostSocket, &connSet);
} else {
firstOpen = slot_find_empty();
if (firstOpen == -1) {
syslog(LOG_ERR, "MGR: No free connection slots or IPs - no more clients can connect!");
} else {
FD_SET(hostSocket, &connSet);
}
}
max_fd = hostSocket;
FD_SET(sig_fd, &connSet);
if (max_fd < sig_fd) max_fd = sig_fd;
while (1) {
if (select(max_fd + 1, &connSet, NULL, NULL, NULL) != -1) break;
if (errno == EINTR) continue;
syslog(LOG_ERR, "MGR: Error with manager select()!");
syslog_perror("select");
exit(-1);
}
if (FD_ISSET(sig_fd, &connSet)) { /* SIGCHLD */
int signum = sigpipe_read();
if (signum == SIGCHLD)
sigchld_responder(signum);
else if (signum == SIGTERM)
{
if (!keep_connections) sigterm_responder();
return signum;
}
}
if (FD_ISSET(hostSocket, &connSet)) { /* A call came! */
int clientSocket;
struct sockaddr_in client_addr;
/* Accept call and launch PPTPCTRL */
addrsize = sizeof(client_addr);
clientSocket = accept(hostSocket, (struct sockaddr *) &client_addr, &addrsize);
#ifdef HAVE_LIBWRAP
if (clientSocket != -1) {
struct request_info r;
request_init(&r, RQ_DAEMON, "pptpd", RQ_FILE, clientSocket, NULL);
fromhost(&r);
if (!hosts_access(&r)) {
/* send a permission denied message? this is a tcp wrapper
* type deny so probably best to just drop it immediately like
* this, as tcp wrappers usually do.
*/
close(clientSocket);
/* this would never be file descriptor 0, so use it as a error
* value
*/
clientSocket = 0;
}
}
#endif
if (clientSocket == -1) {
/* accept failed, but life goes on... */
syslog(LOG_ERR, "MGR: accept() failed");
syslog_perror("accept");
} else if (clientSocket != 0) {
fd_set rfds;
struct timeval tv;
struct pptp_header ph;
/* TODO: this select below prevents
other connections from being
processed during the wait for the
first data packet from the
client. */
/*
* DOS protection: get a peek at the first packet
* and do some checks on it before we continue.
* A 10 second timeout on the first packet seems reasonable
* to me, if anything looks sus, throw it away.
*/
FD_ZERO(&rfds);
FD_SET(clientSocket, &rfds);
tv.tv_sec = pptp_stimeout;
tv.tv_usec = 0;
if (select(clientSocket + 1, &rfds, NULL, NULL, &tv) <= 0) {
syslog(LOG_ERR, "MGR: dropped slow initial connection");
close(clientSocket);
continue;
}
if (recv(clientSocket, &ph, sizeof(ph), MSG_PEEK) !=
sizeof(ph)) {
syslog(LOG_ERR, "MGR: dropped small initial connection");
close(clientSocket);
continue;
}
ph.length = ntohs(ph.length);
ph.pptp_type = ntohs(ph.pptp_type);
ph.magic = ntohl(ph.magic);
ph.ctrl_type = ntohs(ph.ctrl_type);
if (ph.length <= 0 || ph.length > PPTP_MAX_CTRL_PCKT_SIZE) {
syslog(LOG_WARNING, "MGR: initial packet length %d outside "
"(0 - %d)", ph.length, PPTP_MAX_CTRL_PCKT_SIZE);
goto dos_exit;
}
if (ph.magic != PPTP_MAGIC_COOKIE) {
syslog(LOG_WARNING, "MGR: initial packet bad magic");
goto dos_exit;
}
if (ph.pptp_type != PPTP_CTRL_MESSAGE) {
syslog(LOG_WARNING, "MGR: initial packet has bad type");
goto dos_exit;
}
if (ph.ctrl_type != START_CTRL_CONN_RQST) {
syslog(LOG_WARNING, "MGR: initial packet has bad ctrl type "
"0x%x", ph.ctrl_type);
dos_exit:
close(clientSocket);
continue;
}
#ifndef HAVE_FORK
switch (ctrl_pid = vfork()) {
#else
switch (ctrl_pid = fork()) {
#endif
case -1: /* error */
syslog(LOG_ERR, "MGR: fork() failed launching " PPTP_CTRL_BIN);
close(clientSocket);
break;
case 0: /* child */
close(hostSocket);
if (pptp_debug)
syslog(LOG_DEBUG, "MGR: Launching " PPTP_CTRL_BIN " to handle client");
connectCall(clientSocket, !pptp_delegate ? firstOpen : 0);
_exit(1);
/* NORETURN */
default: /* parent */
close(clientSocket);
unique_call_id += MAX_CALLS_PER_TCP_LINK;
if (!pptp_delegate)
slot_set_pid(firstOpen, ctrl_pid);
break;
}
}
} /* FD_ISSET(hostSocket, &connSet) */
} /* while (1) */
} /* pptp_manager() */
/*
* Author: Kevin Thayer
*
* This creates a socket to listen on, sets the max # of pending connections and
* various other options.
*
* Returns the fd of the host socket.
*
* The function return values are:
* 0 for sucessful
* -1 for bad socket creation
* -2 for bad socket options
* -3 for bad bind
* -4 for bad listen
*/
static int createHostSocket(int *hostSocket)
{
int opt = 1;
struct sockaddr_in address;
#ifdef HAVE_GETSERVBYNAME
struct servent *serv;
#endif
/* create the master socket and check it worked */
if ((*hostSocket = vrf_socket(vrf, AF_INET, SOCK_STREAM, 0)) <= 0)
return -1;
/* set master socket to allow daemon to be restarted with connections active */
if (setsockopt(*hostSocket, SOL_SOCKET, SO_REUSEADDR,
(char *) &opt, sizeof(opt)) < 0)
return -2;
/* set up socket */
memset(&address, 0, sizeof(address));
address.sin_family = AF_INET;
if(bindaddr)
address.sin_addr.s_addr = inet_addr(bindaddr);
else
address.sin_addr.s_addr = INADDR_ANY;
#ifdef HAVE_GETSERVBYNAME
if ((serv = getservbyname("pptp", "tcp")) != NULL) {
address.sin_port = serv->s_port;
} else
#endif
address.sin_port = htons(PPTP_PORT);
/* bind the socket to the pptp port */
if (bind(*hostSocket, (struct sockaddr *) &address, sizeof(address)) < 0)
return -3;
/* minimal backlog to avoid DoS */
if (listen(*hostSocket, 3) < 0)
return -4;
return 0;
}
