Add netstat-tulp.sh

netstat-tulp.sh

@@ -0,0 +1,98 @@
+#!/bin/ksh
+
+# OpenBSD equivalent-ish to:
+#
+#   Linux: netstat -tulpn
+#
+# Shows listening TCP sockets and UDP sockets together with
+# the process using the socket when fstat can identify it.
+#
+# Best run as root for complete process information.
+
+printf "%-5s %-7s %-8s %-22s %-22s %s\n" \
+    "PROTO" "PID" "USER" "LOCAL ADDRESS" "FOREIGN ADDRESS" "PROCESS"
+
+printf "%-5s %-7s %-8s %-22s %-22s %s\n" \
+    "-----" "-------" "--------" "----------------------" \
+    "----------------------" "-------"
+
+# ------------------------------------------------------------
+# TCP listening sockets
+# ------------------------------------------------------------
+
+netstat -an -f inet 2>/dev/null |
+awk '$1 ~ /^tcp/ && $6 == "LISTEN" {
+    print $1, $4, $5
+}' |
+while read proto local foreign
+do
+    # Extract port from local address.
+    port="${local##*.}"
+
+    # Try to find the process owning this socket.
+    owner="$(
+        fstat 2>/dev/null |
+        awk -v port="$port" '
+            $0 ~ ("\\*:" port "([^0-9]|$)") ||
+            $0 ~ ("\\." port "([^0-9]|$)") {
+                print $1, $2, $3
+                exit
+            }
+        '
+    )"
+
+    if [ -n "$owner" ]; then
+        set -- $owner
+
+        user="$1"
+        process="$2"
+        pid="$3"
+    else
+        user="-"
+        process="-"
+        pid="-"
+    fi
+
+    printf "%-5s %-7s %-8s %-22s %-22s %s\n" \
+        "$proto" "$pid" "$user" "$local" "$foreign" "$process"
+done
+
+
+# ------------------------------------------------------------
+# UDP sockets
+# ------------------------------------------------------------
+
+netstat -an -f inet 2>/dev/null |
+awk '$1 ~ /^udp/ {
+    print $1, $4, $5
+}' |
+while read proto local foreign
+do
+    port="${local##*.}"
+
+    owner="$(
+        fstat 2>/dev/null |
+        awk -v port="$port" '
+            $0 ~ ("\\*:" port "([^0-9]|$)") ||
+            $0 ~ ("\\." port "([^0-9]|$)") {
+                print $1, $2, $3
+                exit
+            }
+        '
+    )"
+
+    if [ -n "$owner" ]; then
+        set -- $owner
+
+        user="$1"
+        process="$2"
+        pid="$3"
+    else
+        user="-"
+        process="-"
+        pid="-"
+    fi
+
+    printf "%-5s %-7s %-8s %-22s %-22s %s\n" \
+        "$proto" "$pid" "$user" "$local" "$foreign" "$process"
+done