1 files changed, 80 insertions, 0 deletions
diff --git a/update-ddns.in b/update-ddns.in
new file mode 100644
index 0000000..da7facd
--- /dev/null
+++ b/update-ddns.in
@@ -0,0 +1,80 @@
+#!/bin/bash
+
+set -e
+
+stty &> /dev/null || \
+  sleep $[$RANDOM%60]
+
+if ! ipCmd="$(which ip 2> /dev/null)"
+then
+  for p1 in / /usr/
+  do
+    for p2 in bin/ sbin/
+    do
+      ipCmd="${p1}${p2}ip"
+      [ -x "${ipCmd}" ] && break
+    done
+    [ -x "${ipCmd}" ] && break
+  done
+fi
+
+while read -r ipVer authToken dev dnsName
+do
+
+  if [[ "${ipVer}" = "#"* ]] || [ -z "${ipVer}" ]
+  then
+    continue
+  fi
+
+  if [ ${ipVer} == "4" ]
+  then
+    dnsVer="A"
+    inetVer="inet"
+    syncPre=""
+  elif [ ${ipVer} == "6" ] 
+  then
+    dnsVer="AAAA"
+    inetVer="inet6"
+    syncPre="v6."
+  else
+    >&2 echo 'Error: First column in "#ETCDIR#/update-ddns.conf" needs to be "4" or "6"!'
+    exit 1
+  fi
+
+  if [ -z "${dnsName}" ]
+  then
+    dnsIps="$(
+      curl -${ipVer} "${dev}" 2> /dev/null
+    )"
+    ips="1"
+  else
+    dnsIps="$(
+      dig "${dnsName}" ${dnsVer} | \
+        grep -v '^\s*\(;\|$\)' | \
+        grep "\s${dnsVer}\s" | \
+        awk '{print $5}' | \
+        sort -u
+    )"
+
+    ips="$(
+      "${ipCmd}" addr show dev "${dev}" | \
+        grep "^\s*${inetVer}\s.*\sscope\sglobal\s" | \
+        awk '{print $2}' | \
+        cut -d/ -f1 | \
+        sort -u
+    )"
+  fi
+
+  if [ -z "$(
+    (
+      echo "${dnsIps}"
+      echo "${ips}"
+    ) | \
+      sort | \
+      uniq -d
+  )" ]
+  then
+    echo curl -sS "https://${syncPre}sync.afraid.org/u/${authToken}/"
+  fi
+
+done < #ETCDIR#/update-ddns.conf