Adding Android.mk files to build charon and libstrongswan with the Android build system.

Android.mk

@@ -0,0 +1,54 @@
+LOCAL_PATH := $(call my-dir)
+include $(CLEAR_VARS)
+
+# this is the list of plugins that are built into libstrongswan and charon
+# also these plugins are loaded by default (if not changed in strongswan.conf)
+strongswan_PLUGINS := aes des sha1 sha2 md5 fips-prf random x509 pubkey pkcs1 \
+	pem xcbc hmac gmp kernel-netlink socket-default attr android
+
+# helper macros to only add source files for plugins included in the list above
+plugin_enabled = $(findstring $(1), $(strongswan_PLUGINS))
+add_plugin = $(if $(call plugin_enabled,$(1)), \
+				$(addprefix plugins/$(subst -,_,$(strip $(1))/),$(2)))
+
+# includes
+libvstr_PATH = external/strongswan-support/vstr/include
+libgmp_PATH = external/strongswan-support/gmp
+
+# CFLAGS (partially from a configure run using droid-gcc)
+strongswan_CFLAGS := \
+	-Wno-format \
+	-Wno-pointer-sign \
+	-Wno-sign-compare \
+	-Wno-strict-aliasing \
+	-DHAVE___BOOL \
+	-DHAVE_STDBOOL_H \
+	-DHAVE_ALLOCA_H \
+	-DHAVE_ALLOCA \
+	-DHAVE_CLOCK_GETTIME \
+	-DHAVE_PTHREAD_COND_TIMEDWAIT_MONOTONIC \
+	-DHAVE_PRCTL \
+	-DHAVE_LINUX_UDP_H \
+	-DHAVE_STRUCT_SADB_X_POLICY_SADB_X_POLICY_PRIORITY \
+	-DHAVE_IPSEC_MODE_BEET \
+	-DHAVE_IPSEC_DIR_FWD \
+	-DMONOLITHIC \
+	-DUSE_VSTR \
+	-DROUTING_TABLE=0 \
+	-DROUTING_TABLE_PRIO=220 \
+	-DVERSION=\"4.4.0\" \
+	-DPLUGINS='"$(strongswan_PLUGINS)"' \
+	-DIPSEC_DIR=\"/system/bin\" \
+	-DIPSEC_PIDDIR=\"/data/misc/vpn\" \
+	-DSTRONGSWAN_CONF=\"/system/etc/strongswan.conf\" \
+	-DDEV_RANDOM=\"/dev/random\" \
+	-DDEV_URANDOM=\"/dev/urandom\"
+
+# only for Android 2.0+
+strongswan_CFLAGS += \
+	-DHAVE_IN6ADDR_ANY
+
+include $(addprefix $(LOCAL_PATH)/src/,$(addsuffix /Android.mk, \
+		charon \
+		libstrongswan \
+	))