blob: ff0ce53ea50e2084216bfd1d216d8a2c2e7c6d3f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
|
#!/bin/sh -e
# Display TCP packets
# code from:
# https://notes.tweakblogs.net/blog/7955/using-netcat-to-build-a-simple-tcp-proxy-in-linux.html
if [ $# != 3 ]
then
echo "usage: $0 <src-port> <dst-host> <dst-port>"
exit 0
fi
TMP=`mktemp -d`
BACK=$TMP/pipe.back
SENT=$TMP/pipe.sent
RCVD=$TMP/pipe.rcvd
trap 'rm -rf "$TMP"' EXIT
mkfifo -m 0600 "$BACK" "$SENT" "$RCVD"
sed 's/^/ => /' <"$SENT" &
sed 's/^/<= /' <"$RCVD" &
nc -l 127.0.0.1 "$1" <"$BACK" | tee "$SENT" | nc "$2" "$3" | tee "$RCVD" >"$BACK"
|