From ff9d5e13c9150c62fe698e4bc5541e6f92b241d0 Mon Sep 17 00:00:00 2001
From: Jo-Philipp Wich <jow@openwrt.org>
Date: Wed, 13 Mar 2013 16:25:56 +0100
Subject: [PATCH] Make nat reflection src address configurable by introducing a
 reflection_src parameter which can be set to "external" or "internal"

---
 options.c   | 12 ++++++++++++
 options.h   |  8 ++++++++
 redirects.c | 12 ++++++++++--
 3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/options.c b/options.c
index 8effd2a..5c529b3 100644
--- a/options.c
+++ b/options.c
@@ -97,6 +97,11 @@ static const char *include_types[] = {
 	"restore",
 };
 
+static const char *reflection_sources[] = {
+	"internal",
+	"external",
+};
+
 
 bool
 fw3_parse_bool(void *ptr, const char *val)
@@ -664,6 +669,13 @@ fw3_parse_include_type(void *ptr, const char *val)
 	                  FW3_INC_TYPE_SCRIPT, FW3_INC_TYPE_RESTORE);
 }
 
+bool
+fw3_parse_reflection_source(void *ptr, const char *val)
+{
+	return parse_enum(ptr, val, reflection_sources,
+	                  FW3_REFLECTION_INTERNAL, FW3_REFLECTION_EXTERNAL);
+}
+
 
 void
 fw3_parse_options(void *s, const struct fw3_option *opts,
diff --git a/options.h b/options.h
index c84fd28..bb98fb6 100644
--- a/options.h
+++ b/options.h
@@ -117,6 +117,12 @@ enum fw3_include_type
 	FW3_INC_TYPE_RESTORE  = 1,
 };
 
+enum fw3_reflection_source
+{
+	FW3_REFLECTION_INTERNAL = 0,
+	FW3_REFLECTION_EXTERNAL = 1,
+};
+
 struct fw3_ipset_datatype
 {
 	struct list_head list;
@@ -355,6 +361,7 @@ struct fw3_redirect
 	const char *extra;
 
 	bool reflection;
+	enum fw3_reflection_source reflection_src;
 };
 
 struct fw3_forward
@@ -464,6 +471,7 @@ bool fw3_parse_ipset_method(void *ptr, const char *val);
 bool fw3_parse_ipset_datatype(void *ptr, const char *val);
 
 bool fw3_parse_include_type(void *ptr, const char *val);
+bool fw3_parse_reflection_source(void *ptr, const char *val);
 
 bool fw3_parse_date(void *ptr, const char *val);
 bool fw3_parse_time(void *ptr, const char *val);
diff --git a/redirects.c b/redirects.c
index f91cd47..b42201f 100644
--- a/redirects.c
+++ b/redirects.c
@@ -53,6 +53,8 @@ const struct fw3_option fw3_redirect_opts[] = {
 	FW3_OPT("monthdays",           monthdays, redirect,     time.monthdays),
 
 	FW3_OPT("reflection",          bool,      redirect,     reflection),
+	FW3_OPT("reflection_src",      reflection_source,
+	                                          redirect,     reflection_src),
 
 	FW3_OPT("target",              target,    redirect,     target),
 
@@ -324,7 +326,7 @@ print_redirect(enum fw3_table table, enum fw3_family family,
                struct fw3_redirect *redir, int num)
 {
 	struct list_head *ext_addrs, *int_addrs;
-	struct fw3_address *ext_addr, *int_addr;
+	struct fw3_address *ext_addr, *int_addr, ref_addr;
 	struct fw3_device *ext_net, *int_net;
 	struct fw3_protocol *proto;
 	struct fw3_mac *mac;
@@ -433,6 +435,12 @@ print_redirect(enum fw3_table table, enum fw3_family family,
 				if (!proto || (proto->protocol != 6 && proto->protocol != 17))
 					continue;
 
+				if (redir->reflection_src == FW3_REFLECTION_INTERNAL)
+					ref_addr = *int_addr;
+				else
+					ref_addr = *ext_addr;
+
+				ref_addr.mask = 32;
 				ext_addr->mask = 32;
 
 				if (table == FW3_TABLE_NAT)
@@ -452,7 +460,7 @@ print_redirect(enum fw3_table table, enum fw3_family family,
 					fw3_format_sport_dport(NULL, &redir->port_redir);
 					fw3_format_time(&redir->time);
 					fw3_format_comment(redir->name, " (reflection)");
-					print_snat_dnat(FW3_FLAG_SNAT, ext_addr, NULL);
+					print_snat_dnat(FW3_FLAG_SNAT, &ref_addr, NULL);
 				}
 				else if (table == FW3_TABLE_FILTER)
 				{
-- 
2.11.0