Add doctor for FlexGW dependencies check.

scripts/doctor

@@ -0,0 +1,77 @@
+#!/usr/bin/env bash
+#
+# Summary: Verify FlexGW Dependencies.
+#
+# Usage: doctor
+#
+
+set -e
+
+STATUS=0
+
+# zip
+if ! command -v zip 1>/dev/null 2>&1; then
+  echo -e "FlexGW: zip is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# curl
+if ! command -v curl 1>/dev/null 2>&1; then
+  echo -e "FlexGW: curl is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# wget
+if ! command -v wget 1>/dev/null 2>&1; then
+  echo -e "FlexGW: wget is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# dmidecode
+if ! command -v dmidecode 1>/dev/null 2>&1; then
+  echo -e "FlexGW: dmidecode is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# openssl
+if ! command -v openssl 1>/dev/null 2>&1; then
+  echo -e "FlexGW: openssl is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# strongswan
+if ! command -v strongswan 1>/dev/null 2>&1; then
+  echo -e "FlexGW: strongswan is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# openvpn
+if ! command -v openvpn 1>/dev/null 2>&1; then
+  echo -e "FlexGW: strongswan is not installed.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# redirects
+if sysctl -a | egrep "ipv4.*(accept|send)_redirects" | awk -F "=" '{print $2}' | grep -sqw '1' 2>/dev/null; then
+  sysctl -a | egrep "ipv4.*(accept|send)_redirects" 1>&2
+  echo -e "FlexGW: found error settings, please set these value to 0.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# ip_forward
+if sysctl -a | grep "net.ipv4.ip_forward" | awk -F "=" '{print $2}' | grep -sqw '0' 2>/dev/null; then
+  sysctl -a | grep "net.ipv4.ip_forward" 1>&2
+  echo -e "FlexGW: found error settings, please set this value to 1.\n" 1>&2
+  STATUS=$((STATUS+1))
+fi
+
+# result
+if [ "${STATUS}" == "0" ]; then
+  echo -e "\033[0;32mCongratulations! You are ready to go!\033[0m"
+else
+  { echo -e "\033[0;31m\033[0m"
+    echo -e "\033[0;31mProblem(s) detected while checking system.\033[0m"
+  } 1>&2
+fi
+
+exit "${STATUS}"