Implemented support for proxydhcp variables (disbaled by default) (#953)

* Implemented support for proxydhcp variables (disabled by default)

roles/netbootxyz/templates/disks/netboot.xyz.j2

@@ -20,14 +20,25 @@ iseq ${site_name} netboot.xyz || echo ${bold}${fg_whi}Powered by ${fg_gre}netboo
 prompt --key m --timeout 4000 Hit the ${bold}m${boldoff} key to open failsafe menu... && goto failsafe || goto dhcp
 
 :dhcp
-echo
 dhcp || goto netconfig
-isset ${next-server} && iseq ${filename} {{ site_name }}.kpxe && goto tftpmenu ||
-isset ${next-server} && iseq ${filename} {{ site_name }}-undionly.kpxe && goto tftpmenu ||
-isset ${next-server} && iseq ${filename} {{ site_name }}.efi && goto tftpmenu ||
-isset ${next-server} && iseq ${filename} {{ site_name }}-snp.efi && goto tftpmenu ||
-isset ${next-server} && iseq ${filename} {{ site_name }}-snponly.efi && goto tftpmenu ||
-isset ${next-server} && iseq ${filename} {{ site_name }}-arm64.efi && goto tftpmenu ||
+isset ${next-server} && isset ${proxydhcp/next-server} && goto choose-tftp || set tftp-server ${next-server} && goto load-custom-ipxe
+
+:choose-tftp
+# Load "proxy settings" from root server
+chain tftp://${next-server}/local-vars.ipxe || echo ${VARS_ERR}
+# Check if the proxy-dhcp-vars script has made any usable command about how to progress with a next-server and a proxy-next-server being set
+isset ${use_proxydhcp_settings} || prompt --key p --timeout 4000 DHCP proxy detected. Press ${bold}p${boldoff} to boot from && set use_proxydhcp_settings true
+isset ${use_proxydhcp_settings} || set use_proxydhcp_settings false
+iseq ${use_proxydhcp_settings} true && set tftp-server ${proxydhcp/next-server} || set tftp-server ${next-server}
+goto load-custom-ipxe
+
+:load-custom-ipxe
+isset ${tftp-server} && iseq ${filename} {{ site_name }}.kpxe && goto tftpmenu ||
+isset ${tftp-server} && iseq ${filename} {{ site_name }}-undionly.kpxe && goto tftpmenu ||
+isset ${tftp-server} && iseq ${filename} {{ site_name }}.efi && goto tftpmenu ||
+isset ${tftp-server} && iseq ${filename} {{ site_name }}-snp.efi && goto tftpmenu ||
+isset ${tftp-server} && iseq ${filename} {{ site_name }}-snponly.efi && goto tftpmenu ||
+isset ${tftp-server} && iseq ${filename} {{ site_name }}-arm64.efi && goto tftpmenu ||
 goto menu
 
 :failsafe
@@ -79,10 +90,10 @@ echo Attempting chainload of ${boot_domain}...
 goto menu || goto failsafe
 
 :tftpmenu
-chain tftp://${next-server}/local-vars.ipxe || echo ${VARS_ERR}
-isset ${hostname} && chain --autofree tftp://${next-server}/HOSTNAME-${hostname}.ipxe || echo Custom boot by Hostname not found trying MAC...
-chain --autofree tftp://${next-server}/MAC-${mac:hexraw}.ipxe || echo Custom boot by MAC not found booting default...
-chain --autofree tftp://${next-server}/menu.ipxe || echo ${TFTP_ERR} && goto menu
+chain tftp://${tftp-server}/local-vars.ipxe || echo ${VARS_ERR}
+isset ${hostname} && chain --autofree tftp://${tftp-server}/HOSTNAME-${hostname}.ipxe || echo Custom boot by Hostname not found trying MAC...
+chain --autofree tftp://${tftp-server}/MAC-${mac:hexraw}.ipxe || echo Custom boot by MAC not found booting default...
+chain --autofree tftp://${tftp-server}/menu.ipxe || echo ${TFTP_ERR} && goto menu
 
 :menu
 {% if bootloader_https_enabled | bool %}

roles/netbootxyz/templates/local-vars.ipxe.j2

@@ -3,3 +3,8 @@
 
 ### set to enable enable github custom menu
 #set github_user my_github_username
+
+# If a DHCP proxy server is found and this variable is set to true, the tftp server provided by the DHCP proxy will be used instead of the tftp server provided by the root DHCP
+# Please note that this variable is always read from the local-vars.ipxe onb the tftp server the root DHCP provided
+# If the variable isn't present at runtime, the user will be queried to press a key to boot from the proxy DHCP prtovided ftfp server
+#set use_proxydhcp_settings true

roles/netbootxyz/templates/menu/netinfo.ipxe.j2

@@ -17,5 +17,14 @@ item --gap Next-server:
 item nextserver ${space} ${next-server}
 item --gap Filename:
 item filename ${space} ${netX/filename}
+# Proxy DHCP info (Will only be displayed if proxydhcp is set)
+item --gap DHCP proxy present
+isset ${proxydhcp} && item proxy ${space} Yes || item proxy ${space} No
+isset ${proxydhcp} && item --gap DHCP proxy next-server ||
+isset ${proxydhcp} && item proxy-nextserver ${space} ${proxydhcp/next-server} ||
+isset ${proxydhcp} && item --gap Using DHCP proxy next-server ||
+isset ${proxydhcp} && iseq ${proxydhcp/next-server} ${tftp-server} && echo Yes || echo No (Using default next-server ${tftp-server})
+
+
 choose empty ||
 exit