[PATCH] nping: bind to interface on Linux for IPv4 send-ip

[ValdikSS via dev <dev () nmap org>]

Linux RAW sockets need to be bound to interface, if the interface is
L3 tunnel (OpenVPN TUN for example).
Otherwise the packet goes via default route, regardless of
`--interface` or `--source-ip` options.
---
 nping/ProbeMode.cc | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/nping/ProbeMode.cc b/nping/ProbeMode.cc
index 199329b40..ba4c3f82d 100644
--- a/nping/ProbeMode.cc
+++ b/nping/ProbeMode.cc
@@ -807,6 +807,17 @@ int ProbeMode::fillPacketTCP(NpingTarget *target, u16 port, u8 *buff, int buffle
         }else{
             t.setSum();
         }
+
+        /* Bind IPv4 socket to a specific network interface */
+        if ( o.issetDevice() )  {
+            /* It seems that SO_BINDTODEVICE only work on Linux */
+            #ifdef LINUX
+            if (setsockopt(rawfd, SOL_SOCKET, SO_BINDTODEVICE, o.getDevice(), strlen(o.getDevice())+1) == -1) {
+                nping_warning(QT_2, "Error binding IPv4 socket to device %s", o.getDevice() );
+            }
+            #endif
+        }
+
         /* Store result in user supplied buffer */
         *filledlen = i.dumpToBinaryBuffer(buff, bufflen);
 
-- 
2.45.1

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