Added ability to change the hostname and admin email in Proxy

(cherry picked from commit 3bcaaa9b)
(cherry picked from commit 98b3b2b2)
(cherry picked from commit fe8706b6)
(cherry picked from commit c013ef01)
(cherry picked from commit a6dcd976)

src/opnsense/mvc/app/controllers/OPNsense/Proxy/forms/main.xml

@@ -74,6 +74,20 @@
                 <help><![CDATA[Select what to do with X-Forwarded for header.]]></help>
                 <advanced>true</advanced>
             </field>
+            <field>
+                <id>proxy.general.VisibleHostname</id>
+                <label>Visible Hostname</label>
+                <type>text</type>
+                <help><![CDATA[This is the hostname to be displayed in proxy server error messages.]]></help>
+                <advanced>true</advanced>
+            </field>
+            <field>
+                <id>proxy.general.VisibleEmail</id>
+                <label>Administrator's Email</label>
+                <type>text</type>
+                <help><![CDATA[This is the email address displayed in error messages to the users.]]></help>
+                <advanced>true</advanced>
+            </field>
             <field>
                 <id>proxy.general.suppressVersion</id>
                 <label>Suppress version string</label>

src/opnsense/mvc/app/models/OPNsense/Proxy/Proxy.xml

@@ -69,6 +69,17 @@
                 <default>0</default>
                 <Required>N</Required>
             </suppressVersion>
+            <VisibleEmail type="EmailField">
+                <default>admin@localhost</default>
+                <Required>N</Required>
+                <ValidationMessage>Please enter a valid email address.</ValidationMessage>
+            </VisibleEmail>
+            <VisibleHostname type="TextField">
+                <default>localhost</default>
+                <Required>N</Required>
+                <mask>/^([0-9a-zA-Z\.,_\-:]){0,1024}$/u</mask>
+                <ValidationMessage>Please enter a valid servername, ip address or leave this option blank.</ValidationMessage>
+            </VisibleHostname>
             <cache>
                 <local>
                     <enabled type="BooleanField">

src/opnsense/service/templates/OPNsense/Proxy/squid.conf

@@ -530,3 +530,11 @@ delay_parameters 1 {{OPNsense.proxy.general.traffic.OverallBandwidthTrotteling|i
 {% endif %}
 # Disable squid logfile rotate to use system defaults
 logfile_rotate 0
+{% if helpers.exists('OPNsense.proxy.general.VisibleHostname') %}
+# Define visible hostname
+visible_hostname {{OPNsense.proxy.general.VisibleHostname}}
+{% endif %}
+{% if helpers.exists('OPNsense.proxy.general.VisibleEmail') %}
+# Define visible email
+cache_mgr {{OPNsense.proxy.general.VisibleEmail}}
+{% endif %}