Merge ~alfonsosanchezbeato/snappy-hwe-snaps/+git/wifi-ap:move-to-ip into ~snappy-hwe-team/snappy-hwe-snaps/+git/wifi-ap:master

[Alfonso Sanchez-Beato]

* Cleanup ip addresses when stopping AP
* Use ip command instead of ifconfig

* Cleanup ip addresses when stopping AP
* Use ip command instead of ifconfig

[System Enablement Bot (system-enablement-ci-bot)]

PASSED: Successfully build documentation, rev: eb78436cc6e08e9530eca80af3565a02b6445323

Generated documentation is available at https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-docs/1133/

[System Enablement Bot (system-enablement-ci-bot)]

PASSED: Continuous integration, rev:eb78436cc6e08e9530eca80af3565a02b6445323
https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build-prepare/300/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=amd64/341
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=arm64/341
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=armhf/341
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=i386/341
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-docs/1133
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-cleanup/876
    None: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-update-mp/913/console

Click here to trigger a rebuild:
https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build-prepare/300/rebuild

review: Approve (continuous-integration)

[Tony Espy (awe)]

Is there a bug associated with the ip address cleanup?

Also, re: the commit message for the ifconfig --> ip change, a better explanation would be:

"ifconfig is deprecated, and is not included in the new core18 base snap, so switching scripts to use the ip command instead."

review: Needs Fixing

[Alfonso Sanchez-Beato (alfonsosanchezbeato)]

@Tony, comments addressed, including adding a bug.

[Tony Espy (awe)]

review: Approve

[System Enablement Bot (system-enablement-ci-bot)]

PASSED: Successfully build documentation, rev: a3e7cd0d4353c8e81178e9919ee5618648d29499

Generated documentation is available at https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-docs/1134/

[System Enablement Bot (system-enablement-ci-bot)]

PASSED: Continuous integration, rev:a3e7cd0d4353c8e81178e9919ee5618648d29499
https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build-prepare/301/
Executed test runs:
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=amd64/342
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=arm64/342
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=armhf/342
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build/ARCHITECTURE=i386/342
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-docs/1134
    SUCCESS: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-cleanup/877
    None: https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-update-mp/914/console

Click here to trigger a rebuild:
https://jenkins.canonical.com/system-enablement/job/snappy-hwe-snaps-snap-build-prepare/301/rebuild

review: Approve (continuous-integration)

diff --git a/bin/ap.sh b/bin/ap.sh
index add2212..80c44e8 100755
--- a/bin/ap.sh
+++ b/bin/ap.sh
@@ -38,7 +38,7 @@ DEFAULT_ACCESS_POINT_INTERFACE="ap0"
 
 # Make sure the configured WiFi interface is really available before
 # doing anything.
-if ! ifconfig "$WIFI_INTERFACE" ; then
+if ! ip link show "$WIFI_INTERFACE" ; then
 	echo "ERROR: WiFi interface $WIFI_INTERFACE is not available!"
 	exit 1
 fi
@@ -65,11 +65,14 @@ do_cleanup() {
 
 	if [ "$SHARE_DISABLED" = "false" ] ; then
 		# flush forwarding rules out
-		iptables --table nat --delete POSTROUTING --out-interface "$SHARE_NETWORK_INTERFACE" -j MASQUERADE
-		iptables --delete FORWARD --in-interface $iface -j ACCEPT
+		iptables --table nat --delete POSTROUTING \
+			--out-interface "$SHARE_NETWORK_INTERFACE" -j MASQUERADE || true
+		iptables --delete FORWARD --in-interface $iface -j ACCEPT || true
 		sysctl -w net.ipv4.ip_forward=0
 	fi
 
+	ip address flush $iface
+
 	if [ "$WIFI_INTERFACE_MODE" = "virtual" ] ; then
 		"$SNAP"/bin/iw dev $iface del
 	elif is_nm_running ; then
@@ -132,7 +135,7 @@ if is_nm_running ; then
 fi
 
 # Initial wifi interface configuration
-if ! ifconfig "$iface" up ; then
+if ! ip link set dev "$iface" up ; then
 	echo "ERROR: Failed to enable WiFi network interface '$iface'"
 
 	# Remove virtual interface again if we created one
@@ -151,7 +154,8 @@ if ! ifconfig "$iface" up ; then
 fi
 
 # Configure interface and give it a moment to settle
-ifconfig "$iface" "$WIFI_ADDRESS" netmask "$WIFI_NETMASK"
+net_prefix=$(get_prefix_from_ip_mask "$WIFI_ADDRESS" "$WIFI_NETMASK")
+ip address add "$WIFI_ADDRESS"/"$net_prefix" dev "$iface"
 sleep 2
 
 if [ "$SHARE_DISABLED" = "false" ] ; then
diff --git a/bin/helper.sh b/bin/helper.sh
index f3426a3..135d5a5 100644
--- a/bin/helper.sh
+++ b/bin/helper.sh
@@ -56,3 +56,50 @@ is_nm_running() {
 	nm_status=$("$SNAP"/bin/nmcli -t -f RUNNING general)
 	[ "$nm_status" = "running" ]
 }
+
+# Returns network prefix from ip, by finding out its class
+# $1: IPv4 address
+ABCMaskLen() {
+    local class
+    # Get first integer from ipv4 address to determine class
+    class=${1%%.*}
+    if [ "$class" -eq 0 ] || [ "$class" -ge 224 ]; then echo 0; return
+    elif [ "$class" -ge 192 ]; then echo 24; return
+    elif [ "$class" -ge 128 ]; then echo 16; return
+    else echo 8; fi
+}
+
+# Returns network prefix from ip/netmask
+# $1: IPv4 address
+# $2: netmask (optional)
+get_prefix_from_ip_mask() {
+    local ip=$1
+    local mask=$2
+    if [[ $mask != [0-9]*.[0-9]*.[0-9]*.[0-9]* ]]; then
+        ABCMaskLen "$ip"
+        return
+    fi
+
+    mask=$mask.
+    local mask_bits=0
+    while true; do
+        # Get integer most to the left in the mask
+        local next=${mask%%.*}
+        if [ -z "$next" ]; then
+            break
+        fi
+        if [ "$next" -eq 0 ];then
+            break
+        fi
+        local right_zeros=0
+        while [ $((next & 1)) -ne 1 ]; do
+            ((next >>= 1)) || true
+            ((right_zeros += 1))
+        done
+        ((mask_bits += 8 - right_zeros))
+        # Remove the analyzed integer from the mask
+        mask=${mask#[0-9]*.}
+    done
+
+    echo $mask_bits
+}