diff --git a/configure.ac b/configure.ac
index 24bb490..668f744 100644
--- a/configure.ac
+++ b/configure.ac
@@ -9,6 +9,7 @@
 
 AC_SUBST(PACKAGE)
 AC_SUBST(VERSION)
+AC_SUBST([TARGET_OS_ARCH])
 
 # Checks for programs
 AM_PROG_AR
@@ -16,6 +17,19 @@
 AC_PROG_INSTALL
 AC_PROG_MAKE_SET
 
+# Checks for arch
+AC_CANONICAL_TARGET
+TARGET_OS_ARCH=""
+AS_CASE([$target_cpu],
+        [x86_64|aarch64*|mips64*|ppc64*|sparc64],
+        [
+            TARGET_OS_ARCH="64"
+        ],
+        [i?86|arm*|mips*|ppc*|sparc],
+        [
+            TARGET_OS_ARCH="32"
+        ])
+
 AX_CHECK_OPENSSL([], [AC_MSG_ERROR(["openssl required and not found"])])
 AC_CHECK_LIB([pam], [pam_start], [], [AC_MSG_ERROR([libpam not found])])