Merge pull request #3489 from pi-hole/ip_validation

Improve IP validation function

advanced/Scripts/webpage.sh

@@ -10,18 +10,22 @@
 # This file is copyright under the latest version of the EUPL.
 # Please see LICENSE file for your rights under this license.
 
-readonly setupVars="/etc/pihole/setupVars.conf"
 readonly dnsmasqconfig="/etc/dnsmasq.d/01-pihole.conf"
 readonly dhcpconfig="/etc/dnsmasq.d/02-pihole-dhcp.conf"
 readonly FTLconf="/etc/pihole/pihole-FTL.conf"
 # 03 -> wildcards
 readonly dhcpstaticconfig="/etc/dnsmasq.d/04-pihole-static-dhcp.conf"
-readonly PI_HOLE_BIN_DIR="/usr/local/bin"
 readonly dnscustomfile="/etc/pihole/custom.list"
 readonly dnscustomcnamefile="/etc/dnsmasq.d/05-pihole-custom-cname.conf"
 
 readonly gravityDBfile="/etc/pihole/gravity.db"
 
+# Source install script for ${setupVars}, ${PI_HOLE_BIN_DIR} and valid_ip()
+readonly PI_HOLE_FILES_DIR="/etc/.pihole"
+# shellcheck disable=SC2034  # used in basic-install
+PH_TEST="true"
+source "${PI_HOLE_FILES_DIR}/automated install/basic-install.sh"
+
 coltable="/opt/pihole/COL_TABLE"
 if [[ -f ${coltable} ]]; then
     source ${coltable}
@@ -227,7 +231,15 @@ SetDNSServers() {
     for index in "${!array[@]}"
     do
         # Replace possible "\#" by "#". This fixes AdminLTE#1427
-        add_setting "PIHOLE_DNS_$((index+1))" "${array[index]//\\#/#}"
+        local ip
+        ip="${array[index]//\\#/#}"
+
+        if valid_ip "${ip}" ; then
+            add_setting "PIHOLE_DNS_$((index+1))" "${ip}"
+        else
+            echo -e "  ${CROSS} Invalid IP has been passed"
+            exit 1
+        fi
     done
 
     if [[ "${args[3]}" == "domain-needed" ]]; then

automated install/basic-install.sh

@@ -1017,22 +1017,16 @@ valid_ip() {
     local ip=${1}
     local stat=1
 
-    # If the IP matches the format xxx.xxx.xxx.xxx,
-    if [[ "${ip}" =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
-        # Save the old Internal Field Separator in a variable
-        OIFS=$IFS
-        # and set the new one to a dot (period)
-        IFS='.'
-        # Put the IP into an array
-        read -r -a ip <<< "${ip}"
-        # Restore the IFS to what it was
-        IFS=${OIFS}
-        ## Evaluate each octet by checking if it's less than or equal to 255 (the max for each octet)
-        [[ "${ip[0]}" -le 255 && "${ip[1]}" -le 255 \
-        && "${ip[2]}" -le 255 && "${ip[3]}" -le 255 ]]
-        # Save the exit code
-        stat=$?
-    fi
+    # One IPv4 element is 8bit: 0 - 256
+    local ipv4elem="(25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]?|0)";
+    # optional port number starting '#' with range of 1-65536
+    local portelem="(#([1-9]|[1-8][0-9]|9[0-9]|[1-8][0-9]{2}|9[0-8][0-9]|99[0-9]|[1-8][0-9]{3}|9[0-8][0-9]{2}|99[0-8][0-9]|999[0-9]|[1-5][0-9]{4}|6[0-4][0-9]{3}|65[0-4][0-9]{2}|655[0-2][0-9]|6553[0-6]))?"
+    # build a full regex string from the above parts
+    local regex="^${ipv4elem}\.${ipv4elem}\.${ipv4elem}\.${ipv4elem}${portelem}$"
+
+    [[ $ip =~ ${regex} ]]
+
+    stat=$?
     # Return the exit code
     return "${stat}"
 }