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--- vnc-4.0b4-unixsrc/network/TcpSocket.cxx.via 2003-09-04 14:04:39.000000000 +0100
+++ vnc-4.0b4-unixsrc/network/TcpSocket.cxx 2003-11-27 18:13:31.000000000 +0000
@@ -57,6 +57,29 @@
static rfb::LogWriter vlog("TcpSocket");
+/* Tunnelling support. */
+int network::findFreeTcpPort (void)
+{
+ int sock, port;
+ struct sockaddr_in addr;
+ memset(&addr, 0, sizeof(addr));
+ addr.sin_family = AF_INET;
+ addr.sin_addr.s_addr = INADDR_ANY;
+
+ if ((sock = socket (AF_INET, SOCK_STREAM, 0)) < 0)
+ throw SocketException ("unable to create socket", errorNumber);
+
+ for (port = TUNNEL_PORT_OFFSET + 99; port > TUNNEL_PORT_OFFSET; port--) {
+ addr.sin_port = htons ((unsigned short) port);
+ if (bind (sock, (struct sockaddr *)&addr, sizeof (addr)) == 0) {
+ close (sock);
+ return port;
+ }
+ }
+ throw SocketException ("no free port in range", 0);
+ return 0;
+}
+
void
TcpSocket::initTcpSockets() {
--- vnc-4.0b4-unixsrc/network/TcpSocket.h.via 2003-08-11 10:44:53.000000000 +0100
+++ vnc-4.0b4-unixsrc/network/TcpSocket.h 2003-11-27 18:13:31.000000000 +0000
@@ -27,8 +27,14 @@
#include <list>
+/* Tunnelling support. */
+#define TUNNEL_PORT_OFFSET 5500
+
namespace network {
+ /* Tunnelling support. */
+ int findFreeTcpPort (void);
+
class TcpSocket : public Socket {
public:
TcpSocket(int sock, bool close=true);
--- vnc-4.0b4-unixsrc/vncviewer/vncviewer.cxx.via 2003-09-04 14:04:40.000000000 +0100
+++ vnc-4.0b4-unixsrc/vncviewer/vncviewer.cxx 2003-11-27 18:18:53.000000000 +0000
@@ -39,6 +39,7 @@
using namespace network;
using namespace rfb;
+using namespace std;
IntParameter wmDecorationWidth("WMDecorationWidth", "Width of window manager "
"decoration around a window", 6);
@@ -90,6 +91,9 @@
StringParameter geometry("geometry", "X geometry specification", 0);
StringParameter displayname("display", "The X display", 0);
+/* Support for tunnelling */
+StringParameter via("via", "Gateway to tunnel via", "");
+
char aboutText[256];
char* programName;
extern char buildtime[];
@@ -157,6 +161,61 @@
exit(1);
}
+/* Tunnelling support. */
+static void
+interpretViaParam (char **gatewayHost, char **remoteHost,
+ int *remotePort, char **vncServerName,
+ int localPort)
+{
+ const int SERVER_PORT_OFFSET = 5900;
+ char *pos = strchr (*vncServerName, ':');
+ if (pos == NULL)
+ *remotePort = SERVER_PORT_OFFSET;
+ else {
+ int portOffset = SERVER_PORT_OFFSET;
+ size_t len;
+ *pos++ = '\0';
+ len = strlen (pos);
+ if (*pos == ':') {
+ /* Two colons is an absolute port number, not an offset. */
+ pos++;
+ len--;
+ portOffset = 0;
+ }
+ if (!len || strspn (pos, "-0123456789") != len )
+ usage ();
+ *remotePort = atoi (pos) + portOffset;
+ }
+
+ if (**vncServerName != '\0')
+ *remoteHost = *vncServerName;
+
+ *gatewayHost = strDup (via.getValueStr ());
+ *vncServerName = new char[50];
+ sprintf (*vncServerName, "localhost::%d", localPort);
+}
+
+static void
+createTunnel (const char *gatewayHost, const char *remoteHost,
+ int remotePort, int localPort)
+{
+ char *cmd = getenv ("VNC_VIA_CMD");
+ char *percent;
+ char lport[10], rport[10];
+ sprintf (lport, "%d", localPort);
+ sprintf (rport, "%d", remotePort);
+ setenv ("G", gatewayHost, 1);
+ setenv ("H", remoteHost, 1);
+ setenv ("R", rport, 1);
+ setenv ("L", lport, 1);
+ if (!cmd)
+ cmd = "/usr/bin/ssh -f -L \"$L\":\"$H\":\"$R\" \"$G\" sleep 20";
+ /* Compatibility with TightVNC's method. */
+ while ((percent = strchr (cmd, '%')) != NULL)
+ *percent = '$';
+ system (cmd);
+}
+
int main(int argc, char** argv)
{
sprintf(aboutText, "VNC viewer for X version 4.0b4 - built %s\n"
@@ -197,14 +256,25 @@
usage();
}
- if (vncServerName)
- usage();
vncServerName = argv[i];
}
try {
TcpSocket::initTcpSockets();
+ /* Tunnelling support. */
+ if (strlen (via.getValueStr ()) > 0) {
+ char *gatewayHost = "";
+ char *remoteHost = "localhost";
+ int localPort = findFreeTcpPort ();
+ int remotePort;
+ if (!vncServerName)
+ usage();
+ interpretViaParam (&gatewayHost, &remoteHost, &remotePort,
+ &vncServerName, localPort);
+ createTunnel (gatewayHost, remoteHost, remotePort, localPort);
+ }
+
Socket* sock = 0;
if (listenMode) {
--- vnc-4.0b4-unixsrc/vncviewer/vncviewer.man.via 2003-08-07 10:45:06.000000000 +0100
+++ vnc-4.0b4-unixsrc/vncviewer/vncviewer.man 2003-11-27 18:13:31.000000000 +0000
@@ -162,6 +162,23 @@
specific source file if you know the name of its "LogWriter". Default is
\fB*:stderr:30\fP.
+.TP
+\fB\-via\fR \fIgateway\fR
+Automatically create encrypted TCP tunnel to the \fIgateway\fR machine
+before connection, connect to the \fIhost\fR through that tunnel
+(TightVNC\-specific). By default, this option invokes SSH local port
+forwarding, assuming that SSH client binary can be accessed as
+/usr/bin/ssh. Note that when using the \fB\-via\fR option, the host
+machine name should be specified as known to the gateway machine, e.g.
+"localhost" denotes the \fIgateway\fR, not the machine where vncviewer
+was launched. The environment variable \fIVNC_VIA_CMD\fR can override
+the default tunnel command of
+\fB/usr/bin/ssh\ -f\ -L\ "$L":"$H":"$R"\ "$G"\ sleep\ 20\fR. The tunnel
+command is executed with the environment variables \fIH\fR, \fIL\fR, \fIH\fR,
+\fIR\fR, and \fIG\fR taken the values of the local port number, the remote
+host, the port number on the remote host, and the gateway machine
+respectively.
+
.SH SEE ALSO
.BR Xvnc (1)
.BR vncconfig (1),
|