Fix compilation with old NSS (no GetVersion).

configure.in

@@ -140,6 +140,12 @@ AC_DEFUN([CONFIGURE_NSS], [
 
 	PKG_CHECK_MODULES([NSS], [nss],,
 		AC_MSG_ERROR([You need nss library.]))
+
+	saved_CFLAGS=$CFLAGS
+	CFLAGS="$CFLAGS $NSS_CFLAGS"
+	AC_CHECK_DECLS([NSS_GetVersion], [], [], [#include <nss.h>])
+	CFLAGS=$saved_CFLAGS
+
 	CRYPTO_CFLAGS=$NSS_CFLAGS
 	CRYPTO_LIBS=$NSS_LIBS
 	NO_FIPS([])

lib/crypto_backend/crypto_nss.c

@@ -76,7 +76,11 @@ int crypt_backend_init(struct crypt_device *ctx)
 	if (NSS_NoDB_Init(".") != SECSuccess)
 		return -EINVAL;
 
+#if HAVE_DECL_NSS_GETVERSION
 	snprintf(version, 64, "NSS %s", NSS_GetVersion());
+#else
+	snprintf(version, 64, "NSS");
+#endif
 	crypto_backend_initialised = 1;
 	return 0;
 }