src: add tee statement support

index d143121..759883d 100644
@@ -103,6 +103,12 @@ struct ct_stmt {
 extern struct stmt *ct_stmt_alloc(const struct location *loc,
 				  enum nft_ct_keys key,
 				  struct expr *expr);
+struct tee_stmt {
+	struct expr		*gw;
+	const char		*oifname;
+};
+
+struct stmt *tee_stmt_alloc(const struct location *loc);
 
 /**
  * enum stmt_types - statement types

@@ -120,6 +126,7 @@ extern struct stmt *ct_stmt_alloc(const struct location *loc,
  * @STMT_REDIR:		redirect statement
  * @STMT_QUEUE:		QUEUE statement
  * @STMT_CT:		conntrack statement
+ * @STMT_TEE:		tee statement
  */
 enum stmt_types {
 	STMT_INVALID,

@@ -135,6 +142,7 @@ enum stmt_types {
 	STMT_REDIR,
 	STMT_QUEUE,
 	STMT_CT,
+	STMT_TEE,
 };
 
 /**

@@ -184,6 +192,7 @@ struct stmt {
 		struct redir_stmt	redir;
 		struct queue_stmt	queue;
 		struct ct_stmt		ct;
+		struct tee_stmt		tee;
 	};
 };
 

index a3484c6..b2e85e7 100644
@@ -1535,8 +1535,8 @@ static int nat_evaluate_family(struct eval_ctx *ctx, struct stmt *stmt)
 	}
 }
 
-static int nat_evaluate_addr(struct eval_ctx *ctx, struct stmt *stmt,
-			     struct expr **expr)
+static int evaluate_addr(struct eval_ctx *ctx, struct stmt *stmt,
+			 struct expr **expr)
 {
 	struct proto_ctx *pctx = &ctx->pctx;
 	const struct datatype *dtype;

@@ -1577,7 +1577,7 @@ static int stmt_evaluate_nat(struct eval_ctx *ctx, struct stmt *stmt)
 		return err;
 
 	if (stmt->nat.addr != NULL) {
-		err = nat_evaluate_addr(ctx, stmt, &stmt->nat.addr);
+		err = evaluate_addr(ctx, stmt, &stmt->nat.addr);
 		if (err < 0)
 			return err;
 	}

@@ -1646,6 +1646,28 @@ static int stmt_evaluate_log(struct eval_ctx *ctx, struct stmt *stmt)
 	return 0;
 }
 
+static int stmt_evaluate_tee(struct eval_ctx *ctx, struct stmt *stmt)
+{
+	int err;
+
+	switch (ctx->pctx.family) {
+	case NFPROTO_IPV4:
+	case NFPROTO_IPV6:
+		break;
+	default:
+		return stmt_error(ctx, stmt, "tee only supported in ip,ip6");
+	}
+
+	if (stmt->tee.gw == NULL)
+		return stmt_error(ctx, stmt, "tee requires gw parameter");
+
+	err = evaluate_addr(ctx, stmt, &stmt->tee.gw);
+	if (err < 0)
+		return err;
+
+	return 0;
+}
+
 int stmt_evaluate(struct eval_ctx *ctx, struct stmt *stmt)
 {
 #ifdef DEBUG

@@ -1680,6 +1702,8 @@ int stmt_evaluate(struct eval_ctx *ctx, struct stmt *stmt)
 		return stmt_evaluate_redir(ctx, stmt);
 	case STMT_QUEUE:
 		return stmt_evaluate_queue(ctx, stmt);
+	case STMT_TEE:
+		return stmt_evaluate_tee(ctx, stmt);
 	default:
 		BUG("unknown statement type %s\n", stmt->ops->name);
 	}

index 387bb67..ff01e61 100644
@@ -694,6 +694,20 @@ static void netlink_parse_queue(struct netlink_parse_ctx *ctx,
 	list_add_tail(&stmt->list, &ctx->rule->stmts);
 }
 
+static void netlink_parse_tee(struct netlink_parse_ctx *ctx,
+			      const struct location *loc,
+			      const struct nft_rule_expr *nle)
+{
+	struct nft_data_delinearize nld;
+	struct stmt *stmt;
+
+	stmt = tee_stmt_alloc(loc);
+	nld.value = nft_rule_expr_get(nle, NFT_EXPR_TEE_GW, &nld.len);
+	stmt->tee.gw = netlink_alloc_value(loc, &nld);
+	stmt->tee.oifname = nft_rule_expr_get_str(nle, NFT_EXPR_TEE_OIF);
+	list_add_tail(&stmt->list, &ctx->rule->stmts);
+}
+
 static const struct {
 	const char	*name;
 	void		(*parse)(struct netlink_parse_ctx *ctx,

@@ -717,6 +731,7 @@ static const struct {
 	{ .name = "masq",	.parse = netlink_parse_masq },
 	{ .name = "redir",	.parse = netlink_parse_redir },
 	{ .name = "queue",	.parse = netlink_parse_queue },
+	{ .name = "tee",	.parse = netlink_parse_tee },
 };
 
 static int netlink_parse_expr(struct nft_rule_expr *nle, void *arg)

@@ -1102,6 +1117,20 @@ static void stmt_reject_postprocess(struct rule_pp_ctx rctx, struct stmt *stmt)
 	}
 }
 
+static void stmt_tee_postprocess(struct rule_pp_ctx rctx, struct stmt *stmt)
+{
+	switch (rctx.pctx.family) {
+	case NFPROTO_IPV4:
+		stmt->tee.gw->dtype = &ipaddr_type;
+		break;
+	case NFPROTO_IPV6:
+		stmt->tee.gw->dtype = &ip6addr_type;
+		break;
+	default:
+		break;
+	}
+}
+
 static void rule_parse_postprocess(struct netlink_parse_ctx *ctx, struct rule *rule)
 {
 	struct rule_pp_ctx rctx;

@@ -1137,6 +1166,9 @@ static void rule_parse_postprocess(struct netlink_parse_ctx *ctx, struct rule *r
 		case STMT_REJECT:
 			stmt_reject_postprocess(rctx, stmt);
 			break;
+		case STMT_TEE:
+			stmt_tee_postprocess(rctx, stmt);
+			break;
 		default:
 			break;
 		}

index 9bef67b..260f4b6 100644
@@ -798,6 +798,21 @@ static void netlink_gen_ct_stmt(struct netlink_linearize_ctx *ctx,
 	nft_rule_add_expr(ctx->nlr, nle);
 }
 
+static void netlink_gen_tee_stmt(struct netlink_linearize_ctx *ctx,
+				 const struct stmt *stmt)
+{
+	struct nft_rule_expr *nle;
+	struct nft_data_linearize nld;
+	const char *oifname = stmt->tee.oifname;
+
+	nle = alloc_nft_expr("tee");
+	netlink_gen_data(stmt->tee.gw, &nld);
+	nft_rule_expr_set(nle, NFT_EXPR_TEE_GW, nld.value, nld.len);
+	if (oifname != NULL)
+		nft_rule_expr_set_str(nle, NFT_EXPR_TEE_OIF, oifname);
+	nft_rule_add_expr(ctx->nlr, nle);
+}
+
 static void netlink_gen_stmt(struct netlink_linearize_ctx *ctx,
 			     const struct stmt *stmt)
 {

@@ -826,6 +841,8 @@ static void netlink_gen_stmt(struct netlink_linearize_ctx *ctx,
 		return netlink_gen_queue_stmt(ctx, stmt);
 	case STMT_CT:
 		return netlink_gen_ct_stmt(ctx, stmt);
+	case STMT_TEE:
+		return netlink_gen_tee_stmt(ctx, stmt);
 	default:
 		BUG("unknown statement type %s\n", stmt->ops->name);
 	}

index d72c6e9..e05cb32 100644
@@ -377,3 +377,30 @@ struct stmt *redir_stmt_alloc(const struct location *loc)
 {
 	return stmt_alloc(loc, &redir_stmt_ops);
 }
+
+static void tee_stmt_print(const struct stmt *stmt)
+{
+	printf("tee gw ");
+	expr_print(stmt->tee.gw);
+	if (stmt->tee.oifname != NULL)
+		printf(" oifname %s", stmt->tee.oifname);
+}
+
+static void tee_stmt_destroy(struct stmt *stmt)
+{
+	expr_free(stmt->tee.gw);
+	if (stmt->tee.oifname != NULL)
+		xfree(stmt->tee.oifname);
+}
+
+static const struct stmt_ops tee_stmt_ops = {
+	.type		= STMT_TEE,
+	.name		= "tee",
+	.print		= tee_stmt_print,
+	.destroy	= tee_stmt_destroy,
+};
+
+struct stmt *tee_stmt_alloc(const struct location *loc)
+{
+	return stmt_alloc(loc, &tee_stmt_ops);
+}