1 files changed, 54 insertions, 0 deletions
diff --git a/rustables/src/expr/immediate.rs b/rustables/src/expr/immediate.rs
new file mode 100644
index 0000000..e5ccc2a
--- /dev/null
+++ b/rustables/src/expr/immediate.rs
@@ -0,0 +1,54 @@
+use super::{Expression, Register, Rule};
+use rustables_sys as sys;
+use std::ffi::c_void;
+use std::mem::size_of_val;
+use std::os::raw::c_char;
+
+/// An immediate expression. Used to set immediate data.
+/// Verdicts are handled separately by [Verdict].
+#[derive(Debug, Clone, Eq, PartialEq, Hash)]
+pub struct Immediate<T> {
+    pub data: T,
+    pub register: Register,
+}
+
+impl<T> Immediate<T> {
+    pub fn new(data: T, register: Register) -> Self {
+        Self { data, register }
+    }
+}
+
+impl<T> Expression for Immediate<T> {
+    fn to_expr(&self, _rule: &Rule) -> *mut sys::nftnl_expr {
+        unsafe {
+            let expr = try_alloc!(sys::nftnl_expr_alloc(
+                b"immediate\0" as *const _ as *const c_char
+            ));
+
+            sys::nftnl_expr_set_u32(
+                expr,
+                sys::NFTNL_EXPR_IMM_DREG as u16,
+                self.register.to_raw(),
+            );
+
+            sys::nftnl_expr_set(
+                expr,
+                sys::NFTNL_EXPR_IMM_DATA as u16,
+                &self.data as *const _ as *const c_void,
+                size_of_val(&self.data) as u32,
+            );
+
+            expr
+        }
+    }
+}
+
+#[macro_export]
+macro_rules! nft_expr_immediate {
+    (data $value:expr) => {
+        $crate::expr::Immediate {
+            data: $value,
+            register: $crate::expr::Register::Reg1,
+        }
+    };
+}