From ab4841031d7f0eb079d7d13893a5ac3e9943c0b7 Mon Sep 17 00:00:00 2001
From: Sonny <sonnyba871@gmail.com>
Date: Fri, 11 May 2018 16:06:20 +0200
Subject: [PATCH] Add qemu ifup/ifdown scripts

---
 scripts/detect-ip-change   |  0
 scripts/generate-tap       | 24 ++++++++++++++++++++++++
 scripts/qemu-custom-ifdown | 22 ++++++++++++++++++++++
 scripts/qemu-custom-ifup   | 27 +++++++++++++++++++++++++++
 4 files changed, 73 insertions(+)
 mode change 100644 => 100755 scripts/detect-ip-change
 create mode 100755 scripts/generate-tap
 create mode 100755 scripts/qemu-custom-ifdown
 create mode 100755 scripts/qemu-custom-ifup

diff --git a/scripts/detect-ip-change b/scripts/detect-ip-change
old mode 100644
new mode 100755
diff --git a/scripts/generate-tap b/scripts/generate-tap
new file mode 100755
index 0000000..88e8a99
--- /dev/null
+++ b/scripts/generate-tap
@@ -0,0 +1,24 @@
+#!/bin/bash
+# Generate a numbered tap device name
+
+TAP="tap0"
+COUNT=0
+
+while [[ true ]]; do
+    FOUND=false
+
+    for INT in $(ls /sys/class/net); do
+        if [[ $INT == $TAP ]]; then
+            ((COUNT++))
+
+            TAP="tap$COUNT"
+            FOUND=true
+            continue
+        fi
+    done
+
+    if [[ !$FOUND ]]; then
+        break
+    fi
+done
+
diff --git a/scripts/qemu-custom-ifdown b/scripts/qemu-custom-ifdown
new file mode 100755
index 0000000..5860c07
--- /dev/null
+++ b/scripts/qemu-custom-ifdown
@@ -0,0 +1,22 @@
+#!/bin/bash
+# This script removes the specified interface if it exists
+
+if [[ $EUID != 0 ]]; then
+	echo "This script needs sudo priveleges"
+	echo "Exiting..."
+	exit 1
+fi
+
+for INT in $(ls /sys/class/net); do
+    if [[ $INT == $1 ]]; then
+        /sbin/ip link delete dev $1 type tap
+        DELETED=true
+        break
+    fi
+done
+
+if [[ !$DELETED ]]; then
+    echo "Interface $1 not found, nothing to delete"
+    exit 1
+fi 
+
diff --git a/scripts/qemu-custom-ifup b/scripts/qemu-custom-ifup
new file mode 100755
index 0000000..615f8a1
--- /dev/null
+++ b/scripts/qemu-custom-ifup
@@ -0,0 +1,27 @@
+#!/bin/bash
+# This script adds an specified tap interface to first bridge
+# found with the name containing br0
+
+if [[ $EUID != 0 ]]; then
+	echo "This script needs sudo priveleges"
+	echo "Exiting..."
+	exit 1
+fi
+
+for INT in $(ls /sys/class/net); do
+    if [[ $INT == *"br0"*  && -d /sys/class/net/$INT/bridge/. ]]; then
+        BRIDGE="$INT"
+        break
+    fi
+done
+
+if [[ -z $BRIDGE ]]; then
+    echo 'No bridge INTerfaces seen'
+    exit 1
+fi
+
+/sbin/ip tuntap add dev $1 mode tap
+/sbin/ip link set $1 up
+
+/sbin/ip link set dev $1 master $BRIDGE
+