update internet sharing post

source/_posts/2014-02-08-internet-sharing-ipv4-and-ipv6-on-archlinux-using-dnsmasq.markdown

@@ -9,6 +9,8 @@ categories:
 - ipv6 router advertisement
 ---
 
+**Update:** Added adhoc wlan network
+
 A guide to connect with a different machine using a ethernet cable for
 internet sharing or just transferring files:
 
@@ -17,11 +19,12 @@ internet sharing or just transferring files:
     $ pacman -S dnsmasq iproute2
 
 2. Copy over the configuration files at the end of the article and edit the
-   */etc/conf.d/share-internet* to match your network setup.
+   */etc/conf.d/share-internet@\<device\>* to match your network setup. (where
+   \<device\> is your network device)
 
 3. Start the sharing service with systemd
 
-   $ sudo systemctl start internet-sharing.service
+   $ sudo systemctl start internet-sharing@<device>.service
 
 After that the other machine can connect via dhcp. It will get an ipv4
 address from the **10.20.0.0/24** subnet and a ipv6 address from the **fd21:30c2:dd2f::**
@@ -34,10 +37,26 @@ network with the device on which the dhcp service is running.
 
 Happy networking!
 
-{% include_code /etc/conf.d/share-internet lang:bash share-internet/share-internet %}
-
 {% include_code /etc/systemd/system/share-internet.service lang:ini share-internet/share-internet.service %}
 
 {% include_code /etc/dnsmasq.conf lang:ini share-internet/dnsmasq.conf %}
 
 {% include_code /etc/dnsmasq.conf.dhcp lang:bash share-internet/dnsmasq.conf.dhcp %}
+
+Ethernet to Wlan:
+
+{% include_code /etc/conf.d/share-internet@enp0s25 lang:bash share-internet/share-internet@enp0s25 %}
+
+Wlan to Ethernet:
+
+If you have luck and your wifi driver is capable of the infrastructure mode,
+you should take a look at hostadp, in my case I have to create an adhoc network.
+To enable the adhoc network:
+
+   $ sudo systemctl enable wireless-adhoc@\<device\>.service
+
+{% include_code /etc/conf.d/share-internet@wlp3s0 lang:bash share-internet/share-internet@wlp3s0 %}
+
+{% include_code /etc/systemd/system/wireless-adhoc@.service lang:ini share-internet/wireless-adhoc@.service %}
+
+{% include_code /etc/wpa_supplicant/wpa_supplicant-adhoc-wlp3s0.conf lang:bash share-internet/wpa_supplicant-adhoc-wlp3s0.conf %}

source/downloads/code/share-internet/dnsmasq.conf

@@ -3,5 +3,3 @@ server=8.8.8.8
 server=8.8.4.4
 no-resolv
 cache-size=2000
-
-#conf-file=/etc/dnsmasq.conf.dhcp

source/downloads/code/share-internet/dnsmasq.conf.dhcp

@@ -1,10 +0,0 @@
-# no need to modify
-# ingoing and outgoing device will be set by the systemd service
-interface=enp0s25
-no-dhcp-interface=wlp3s0
-dhcp-range=10.20.0.100,10.20.0.199,infinite
-dhcp-option=3,10.20.0.1  # router
-dhcp-option=5,10.20.0.1  # dns
-dhcp-option=42,10.20.0.1 # ntp
-dhcp-range=fd21:30c2:dd2f::,ra-stateless,ra-names,infinite
-enable-ra

source/downloads/code/share-internet/share-internet

@@ -1,4 +0,0 @@
-# Network device where other hosts are connect to, ex: eth0
-INTERNAL_DEVICE="enp0s25"
-# Device which has internet access, ex: wlan0 or usb0
-EXTERNAL_DEVICE="wlp3s0"

source/downloads/code/share-internet/share-internet.service

@@ -1,27 +0,0 @@
-[Unit]
-Description='share internet'
-
-[Service]
-Type=oneshot
-EnvironmentFile=/etc/conf.d/share-internet
-RemainAfterExit=yes
-ExecStart=/usr/bin/sed -ie 's!^#conf-file=/etc/dnsmasq\.conf\.dhcp!conf-file=/etc/dnsmasq.conf.dhcp!' /etc/dnsmasq.conf
-ExecStart=/usr/bin/sed -ie 's/^interface=[[:alnum:]]+/interface=$INTERNAL_DEVICE/' /etc/dnsmasq.conf.dhcp
-ExecStart=/usr/bin/sed -ie 's/^no-dhcp-interface=[[:alnum:]]+/no-dhcp-interface=$EXTERNAL_DEVICE/' /etc/dnsmasq.conf.dhcp
-ExecStart=/usr/bin/iptables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE
-ExecStart=/usr/bin/ip6tables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE
-ExecStart=/usr/bin/sysctl -w net.ipv4.ip_forward=1 net.ipv6.conf.all.forwarding=1
-ExecStart=/usr/bin/ip addr add 10.20.0.1/24 dev $INTERNAL_DEVICE
-ExecStart=/usr/bin/ip addr add fd21:30c2:dd2f::1/64 dev $INTERNAL_DEVICE
-ExecStart=/usr/bin/systemctl restart dnsmasq
-
-ExecStop=/usr/bin/ip addr del 10.20.0.1/24 dev $INTERNAL_DEVICE
-ExecStop=/usr/bin/ip addr del fd21:30c2:dd2f::1/64 dev $INTERNAL_DEVICE
-ExecStop=/usr/bin/sysctl -w net.ipv4.ip_forward=0 net.ipv6.conf.all.forwarding=0
-ExecStop=/usr/bin/iptables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -i $INTERNAL_DEVICE -j MASQUERADE
-ExecStop=/usr/bin/ip6tables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -i $INTERNAL_DEVICE -j MASQUERADE
-ExecStop=/usr/bin/sed -ie 's!^conf-file=/etc/dnsmasq\.conf\.dhcp!#conf-file=/etc/dnsmasq.conf.dhcp!' /etc/dnsmasq.conf
-ExecStop=/usr/bin/systemctl restart dnsmasq
-
-[Install]
-WantedBy=multi-user.target

source/downloads/code/share-internet/share-internet@.service

@@ -0,0 +1,35 @@
+[Unit]
+Description='share internet'
+Conflicts=dnsmasq.service
+Wants=network.target
+Before=network.target
+BindsTo=sys-subsystem-net-devices-%i.device
+After=sys-subsystem-net-devices-%i.device
+
+[Service]
+Type=simple
+EnvironmentFile=/etc/conf.d/share-internet@%i
+ExecStartPre=/usr/bin/dnsmasq --test
+ExecStartPre=/usr/bin/iptables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE
+ExecStartPre=/usr/bin/ip6tables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE
+ExecStartPre=/usr/bin/sysctl -w net.ipv4.ip_forward=1 net.ipv6.conf.all.forwarding=1
+ExecStartPre=/usr/bin/ip link set %i up
+ExecStartPre=/usr/bin/ip addr add ${IP4_ADDRESS}/${IP4_NETMASK} dev %i
+ExecStartPre=/usr/bin/ip addr add ${IP6_ADDRESS}/${IP4_NETMASK} dev %i
+
+ExecStart=/usr/bin/dnsmasq -k --user=dnsmasq --pid-file \
+          --conf-file=/etc/dnsmasq.conf \
+          --interface=%i \
+          --dhcp-range=${IP4_SUBNET},infinite \
+          --dhcp-range=${IP6_SUBNET},ra-stateless,ra-names,infinite \
+          --dhcp-option=3,${IP4_ADDRESS}  \
+          --dhcp-option=5,${IP4_ADDRESS}  \
+          --enable-ra \
+          --no-daemon
+ExecReload=/bin/kill -HUP $MAINPID
+
+ExecStopPost=/usr/bin/ip addr flush dev %i
+ExecStopPost=/usr/bin/ip link set %i down
+ExecStopPost=/usr/bin/sysctl -w net.ipv4.ip_forward=0 net.ipv6.conf.all.forwarding=0
+ExecStopPost=/usr/bin/iptables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE
+ExecStopPost=/usr/bin/ip6tables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE

source/downloads/code/share-internet/share-internet@enp0s25

@@ -0,0 +1,10 @@
+# Device which has internet access, ex: wlan0 or usb0
+EXTERNAL_DEVICE="wlp3s0"
+
+IP4_ADDRESS="10.20.0.1"
+IP4_NETMASK="24"
+IP4_SUBNET="10.20.0.2,10.20.0.255"
+
+IP6_ADDRESS="fd21:30c2:dd2f::1"
+IP6_NETMASK="64"
+IP6_SUBNET="fd21:30c2:dd2f::"

source/downloads/code/share-internet/share-internet@wlp3s0

@@ -0,0 +1,10 @@
+# Device which has internet access, ex: wlan0 or usb0
+EXTERNAL_DEVICE="enp0s20u2"
+
+IP4_ADDRESS="10.20.0.1"
+IP4_NETMASK="24"
+IP4_SUBNET="10.20.0.100,10.20.0.199"
+
+IP6_ADDRESS="fd21:30c2:dd2f::1"
+IP6_NETMASK="64"
+IP6_SUBNET="fd21:30c2:dd2f::"

source/downloads/code/share-internet/wireless-adhoc@.service

@@ -0,0 +1,15 @@
+[Unit]
+Description=Ad-hoc wireless network connectivity (%i)
+Wants=network.target
+Before=network.target
+Conflicts=netctl-auto@.service
+BindsTo=sys-subsystem-net-devices-%i.device
+After=sys-subsystem-net-devices-%i.device
+
+[Service]
+Type=simple
+ExecStartPre=/usr/bin/rfkill unblock wifi
+ExecStart=/usr/sbin//wpa_supplicant -D nl80211,wext -c/etc/wpa_supplicant/wpa_supplicant-adhoc-%I.conf -i%I
+
+[Install]
+RequiredBy=share-internet@%i.service

source/downloads/code/share-internet/wpa_supplicant-adhoc-wlp3s0.conf

@@ -0,0 +1,29 @@
+ctrl_interface=DIR=/run/wpa_supplicant GROUP=wheel
+
+# use 'ap_scan=2' on all devices connected to the network
+ap_scan=2
+
+network={
+    ssid="The.Secure.Network"
+    mode=1
+    frequency=2432
+    proto=WPA
+    key_mgmt=WPA-NONE
+    pairwise=NONE
+    group=TKIP
+    psk="fnord"
+}
+
+# MacOS X and Networmanager aren't capable of using WPA/WPA2 for Adhoc Networks
+#network={
+#    ssid="The.Insecure.Network"
+#    mode=1
+#    frequency=2432
+#    proto=WPA
+#    key_mgmt=NONE
+#    pairwise=NONE
+#    group=TKIP
+#
+#    wep_key0="fnord"
+#    wep_tx_keyidx=0
+#}