tinyproxy: support DisableViaHeader option

This option is required for the proxy to be transparent, and has been
supported since at least 2009. Description taken from upstream.

Signed-off-by: Xu Wang <xwang1498@gmx.com>

net/tinyproxy/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=tinyproxy
 PKG_VERSION:=1.11.1
-PKG_RELEASE:=3
+PKG_RELEASE:=4
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz
 PKG_SOURCE_URL:=https://github.com/tinyproxy/tinyproxy/releases/download/$(PKG_VERSION)

net/tinyproxy/files/tinyproxy.config

@@ -147,6 +147,15 @@ list Allow 127.0.0.1
 #
 option ViaProxyName "tinyproxy"
 
+#
+# DisableViaHeader: When this is set to yes, Tinyproxy does NOT add
+# the Via header to the requests. This virtually puts Tinyproxy into
+# stealth mode. Note that RFC 2616 requires proxies to set the Via
+# header, so by enabling this option, you break compliance.
+# Don't disable the Via header unless you know what you are doing...
+#
+#option DisableViaHeader 1
+
 #
 # The location of the filter file.
 #

net/tinyproxy/files/tinyproxy.init

@@ -132,6 +132,7 @@ start_proxy() {
 	proxy_list "$1" Allow
 
 	proxy_string "$1" ViaProxyName
+	proxy_flag "$1" DisableViaHeader Yes No
 	proxy_string "$1" Filter
 
 	proxy_flag "$1" FilterURLs