diff --git a/lfs/strongswan b/lfs/strongswan
index f227bba66..d1a5b8c15 100644
--- a/lfs/strongswan
+++ b/lfs/strongswan
@@ -24,7 +24,7 @@
 
 include Config
 
-VER        = 5.3.0
+VER        = 5.3.1
 
 THISAPP    = strongswan-$(VER)
 DL_FILE    = $(THISAPP).tar.bz2
@@ -48,7 +48,7 @@ objects = $(DL_FILE)
 
 $(DL_FILE) = $(DL_FROM)/$(DL_FILE)
 
-$(DL_FILE)_MD5 = c52d4228231c2025d9c320d0e9990327
+$(DL_FILE)_MD5 = 66f258901a3d6c271da1a0c7fb3e5013
 
 install : $(TARGET)
 
@@ -78,10 +78,10 @@ $(subst %,%_MD5,$(objects)) :
 $(TARGET) : $(patsubst %,$(DIR_DL)/%,$(objects))
 	@$(PREBUILD)
 	@rm -rf $(DIR_APP) && cd $(DIR_SRC) && tar axf $(DIR_DL)/$(DL_FILE)
-	cd $(DIR_APP) && patch -Np1 -i $(DIR_SRC)/src/patches/strongswan-5.3.0-stroke-Increase-stroke-buffer-size-to-8k.patch
+	cd $(DIR_APP) && patch -Np1 -i $(DIR_SRC)/src/patches/strongswan-5.3.1-build-timeattack.patch
 	cd $(DIR_APP) && patch -Np1 -i $(DIR_SRC)/src/patches/strongswan-ipfire.patch
 
-	cd $(DIR_APP) && [ -x "configure" ] || ./autogen.sh
+	cd $(DIR_APP) && autoreconf -vfi
 	cd $(DIR_APP) && ./configure \
 		--prefix="/usr" \
 		--sysconfdir="/etc" \
diff --git a/src/patches/strongswan-5.3.0-stroke-Increase-stroke-buffer-size-to-8k.patch b/src/patches/strongswan-5.3.0-stroke-Increase-stroke-buffer-size-to-8k.patch
deleted file mode 100644
index 2252e314d..000000000
--- a/src/patches/strongswan-5.3.0-stroke-Increase-stroke-buffer-size-to-8k.patch
+++ /dev/null
@@ -1,34 +0,0 @@
-From 4b59d129fd1026bab37256af0df9ae7ace39e7ba Mon Sep 17 00:00:00 2001
-From: Michael Tremer <michael.tremer@ipfire.org>
-Date: Mon, 27 Apr 2015 18:49:45 +0200
-Subject: [PATCH] stroke: Increase stroke buffer size to 8k
-
-Complicated connections can have lots of arguments
-for the ike= and esp= directives in the ipsec.conf
-configuration file. strongSwan wouldn't import those
-because the size of the message that is send from
-stroke to charon exceeded the limit of 4k.
-
-This patch increases the size of the buffer that
-can be passed to charon to 8k which should be enough
-even for connections with longer configurations.
----
- src/stroke/stroke_msg.h | 2 +-
- 1 file changed, 1 insertion(+), 1 deletion(-)
-
-diff --git a/src/stroke/stroke_msg.h b/src/stroke/stroke_msg.h
-index c2b923f6db9a..c391efa00105 100644
---- a/src/stroke/stroke_msg.h
-+++ b/src/stroke/stroke_msg.h
-@@ -32,7 +32,7 @@
-  */
- #define STROKE_SOCKET IPSEC_PIDDIR "/charon.ctl"
- 
--#define STROKE_BUF_LEN		4096
-+#define STROKE_BUF_LEN		8192
- 
- typedef enum list_flag_t list_flag_t;
- 
--- 
-2.1.0
-
diff --git a/src/patches/strongswan-5.3.1-build-timeattack.patch b/src/patches/strongswan-5.3.1-build-timeattack.patch
new file mode 100644
index 000000000..948c4fc73
--- /dev/null
+++ b/src/patches/strongswan-5.3.1-build-timeattack.patch
@@ -0,0 +1,11 @@
+--- strongswan-5.3.1/scripts/Makefile.am.old	2015-06-04 17:20:43.539244145 +0000
++++ strongswan-5.3.1/scripts/Makefile.am	2015-06-04 17:20:51.760510631 +0000
+@@ -42,7 +42,7 @@
+ dnssec_LDADD = $(top_builddir)/src/libstrongswan/libstrongswan.la
+ aes_test_LDADD = $(top_builddir)/src/libstrongswan/libstrongswan.la
+ settings_test_LDADD = $(top_builddir)/src/libstrongswan/libstrongswan.la
+-timeattack_LDADD = $(top_builddir)/src/libstrongswan/libstrongswan.la
++timeattack_LDADD = $(top_builddir)/src/libstrongswan/libstrongswan.la $(RTLIB)
+ 
+ key2keyid.o :	$(top_builddir)/config.status
+