From df8fcbcb881d31123406e7199266c602958076e7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alexander=20Sch=C3=A4ferdiek?= <alexander@schaeferdiek.eu>
Date: Sun, 8 Sep 2019 14:45:57 +0200
Subject: [PATCH] Add dynv6 as user service

---
 etc/systemd/user/dynv6.service          |  10 ++
 etc/systemd/user/dynv6.timer            |   9 ++
 usr/local/bin/dynv6                     | 121 ++++++++++++++++++++++++
 usr/share/doc/dynv6/.dynv6.conf.example |   7 ++
 4 files changed, 147 insertions(+)
 create mode 100644 etc/systemd/user/dynv6.service
 create mode 100644 etc/systemd/user/dynv6.timer
 create mode 100755 usr/local/bin/dynv6
 create mode 100644 usr/share/doc/dynv6/.dynv6.conf.example

diff --git a/etc/systemd/user/dynv6.service b/etc/systemd/user/dynv6.service
new file mode 100644
index 0000000..28a9bf1
--- /dev/null
+++ b/etc/systemd/user/dynv6.service
@@ -0,0 +1,10 @@
+[Unit]
+Description=Run dynv6
+#OnFailure=systemd_failure_notify@%n.service
+
+[Service]
+Type=oneshot
+ExecStart=dynv6
+
+[Install]
+WantedBy=default.target
diff --git a/etc/systemd/user/dynv6.timer b/etc/systemd/user/dynv6.timer
new file mode 100644
index 0000000..4ba6be1
--- /dev/null
+++ b/etc/systemd/user/dynv6.timer
@@ -0,0 +1,9 @@
+[Unit]
+Description=Run dynv6
+
+[Timer]
+OnCalendar=hourly
+Persistent=true
+
+[Install]
+WantedBy=timers.target
diff --git a/usr/local/bin/dynv6 b/usr/local/bin/dynv6
new file mode 100755
index 0000000..86edc00
--- /dev/null
+++ b/usr/local/bin/dynv6
@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+
+set -e;
+
+usage() {
+USAGE=$(cat <<EOF
+Usage: dynv6 [CONFIG_FILE (absolute path)]
+
+If no CONFIG_FILE is given, HOME/.dynv6.conf is used. This fallback option
+has to exist or the script will exit.
+
+Configuration can be done in any file and any pre-defined variable can be overwritten.
+
+The following are at least required for the script to work:
+- DYNV6_MAIL_ENABLED= // if notify via mail
+- DYNV6_MAIL_ADDRESS="" // (optional) mail.rc has to be configured
+- DYNV6_TOKEN="" // the dynv6 token
+- DYNV6_HOSTNAME="" // the dynv6 hostname
+- DYNV6_DEVICE="" // the (optional) dynv6 device
+- DYNV6_NETMASK="" // the (optional) netmask
+
+You can copy this script to '/usr/local/bin' and use create a custom CONFIG_FILE as user. Examples can be found in '/usr/share/doc/<scriptname>'.
+EOF
+)
+  echo "$USAGE";
+}
+
+# check for config file
+source_config() {
+  local config=$1;
+  local configFallback=$2;
+
+  if [[ ! -f "$config" ]]; then
+    if [[ ! -f "$configFallback" ]]; then
+      echo "No config file specified and could not find default in '$configFallback'!";
+      echo "";
+      usage;
+      exit 1;
+    else
+      config=$configFallback;
+    fi
+  fi
+
+  set -a;
+  source "$config";
+  set +a;
+}
+
+apply_defaults() {
+    [[ -z ${DYNV6_MAIL_ENABLED} ]] && DYNV6_MAIL_ENABLED=false;
+}
+check_required() {
+    if [[ -z ${DYNV6_TOKEN} ]]; then
+      echo "DYNV6_TOKEN is required"
+        exit 1;
+    fi
+    if [[ -z ${DYNV6_HOSTNAME} ]]; then
+      echo "DYNV6_HOSTNAME is required"
+        exit 1;
+    fi
+
+    if [ -e /usr/bin/curl ]; then
+      bin="curl -fsS"
+    elif [ -e /usr/bin/wget ]; then
+      bin="wget -O-"
+    else
+      echo "neither curl nor wget found"
+      exit 1
+    fi
+    }
+
+# check requirements
+CONFIG_FILE="$1";
+FALLBACK_CONFIG_FILE="${HOME}/.dynv6.conf";
+source_config "${CONFIG_FILE}" "${FALLBACK_CONFIG_FILE}";
+apply_defaults;
+check_required;
+
+# DO NOT CHANGE
+token=${DYNV6_TOKEN}
+hostname=${DYNV6_HOSTNAME}
+device=${DYNV6_DEVICE}
+netmask=${DYNV6_NETMASK}
+
+file=$HOME/.dynv6.addr6
+[ -e $file ] && old=`cat $file`
+
+if [ -z "$netmask" ]; then
+  netmask=128
+fi
+
+if [ -n "$device" ]; then
+  device="dev $device"
+fi
+address=$(ip -6 addr list scope global $device | grep -v " fd" | sed -n 's/.*inet6 \([0-9a-f:]\+\).*/\1/p' | head -n 1)
+
+if [ -z "$address" ]; then
+  echo "no IPv6 address found"
+  exit 1
+fi
+
+# address with netmask
+current=$address/$netmask
+
+if [ "$old" = "$current" ]; then
+  echo "IPv6 address unchanged"
+  exit
+fi
+
+# send addresses to dynv6
+$bin "http://dynv6.com/api/update?hostname=$hostname&ipv6=$current&token=$token"
+$bin "http://ipv4.dynv6.com/api/update?hostname=$hostname&ipv4=auto&token=$token"
+
+# save current address
+echo $current > $file
+
+# sent mail that IP changed
+if [ "${DYNV6_MAIL_ENABLED}" = true ]; then
+  HOSTMACHINE=$(hostname)
+  echo -e "IP for ${hostname} changed from '${old}' to '${address}' on host ${HOSTMACHINE}" | mailx -s "[dynv6 ${HOSTMACHINE}] IP changed for ${hostname}" "${DYNV6_MAIL_ADDRESS}"
+fi
diff --git a/usr/share/doc/dynv6/.dynv6.conf.example b/usr/share/doc/dynv6/.dynv6.conf.example
new file mode 100644
index 0000000..79a97f1
--- /dev/null
+++ b/usr/share/doc/dynv6/.dynv6.conf.example
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+DYNV6_MAIL_ENABLED= // if notify via mail
+DYNV6_MAIL_ADDRESS="" // (optional) mail.rc has to be configured
+DYNV6_TOKEN="" // the dynv6 token
+DYNV6_HOSTNAME="" // the dynv6 hostname
+DYNV6_DEVICE="" // the (optional) dynv6 device
+DYNV6_NETMASK="" // the (optional) netmask
\ No newline at end of file