From ea1ea712982c8d4a0dc80ed6e4417c05fee4b902 Mon Sep 17 00:00:00 2001
From: "Chester A. Unal" <chester.a.unal@arinc9.com>
Date: Thu, 19 Feb 2026 12:48:17 +0200
Subject: [PATCH] tcp-in-udp: add

TCP-in-UDP is a lightweight TCP in UDP tunnel utilising eBPF.

Signed-off-by: Chester A. Unal <chester.a.unal@arinc9.com>
---
 net/tcp-in-udp/Makefile | 48 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)
 create mode 100644 net/tcp-in-udp/Makefile

diff --git a/net/tcp-in-udp/Makefile b/net/tcp-in-udp/Makefile
new file mode 100644
index 0000000000..2ef7a3275f
--- /dev/null
+++ b/net/tcp-in-udp/Makefile
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+# Copyright (C) 2025-2026 Chester A. Unal <chester.a.unal@arinc9.com>
+
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=tcp-in-udp
+PKG_RELEASE:=1
+
+PKG_LICENSE:=AGPL-3.0-or-later
+PKG_MAINTAINER:=Chester A. Unal <chester.a.unal@arinc9.com>
+
+PKG_SOURCE_PROTO:=git
+PKG_SOURCE_URL:=https://github.com/multipath-tcp/tcp-in-udp.git
+PKG_SOURCE_DATE:=2026-02-24
+PKG_SOURCE_VERSION:=bf16ad0b1c43853abbcac2053241d28e2bb20d12
+PKG_MIRROR_HASH:=9b5c1f97a6400de3d975366b4cfeceebf6b63eda202dcd51848978730855a878
+
+PKG_BUILD_DEPENDS:=bpf-headers
+
+include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/bpf.mk
+
+define Package/tcp-in-udp
+  SECTION:=net
+  CATEGORY:=Network
+  TITLE:=Lightweight TCP in UDP tunnel using eBPF
+  DEPENDS:=+libbpf $(BPF_DEPENDS)
+endef
+
+# The CompileBPF definition uses -O2 for LLVM_OPT which causes failure to load
+# the BPF programme. Use -O1 which works.
+# $(call CompileBPF,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c,-DBPF_PRINTK_UNSUPPORTED)
+define Build/Compile
+	$(CLANG) -g -target $(BPF_ARCH)-linux-gnu $(BPF_CFLAGS) -DBPF_PRINTK_UNSUPPORTED \
+		-c $(PKG_BUILD_DIR)/tcp_in_udp_tc.c -o $(patsubst %.c,%.bc,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+	$(LLVM_OPT) -O1 -mtriple=$(BPF_TARGET) < $(patsubst %.c,%.bc,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c) > $(patsubst %.c,%.opt,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+	$(LLVM_DIS) < $(patsubst %.c,%.opt,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c) > $(patsubst %.c,%.S,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+	$(LLVM_LLC) -march=$(BPF_TARGET) -mcpu=v3 -filetype=obj -o $(patsubst %.c,%.o,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c) < $(patsubst %.c,%.S,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+	$(CP) $(patsubst %.c,%.o,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c) $(patsubst %.c,%.debug.o,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+	$(LLVM_STRIP) --strip-debug $(patsubst %.c,%.o,$(PKG_BUILD_DIR)/tcp_in_udp_tc.c)
+endef
+
+define Package/tcp-in-udp/install
+	$(INSTALL_DIR) $(1)/usr/lib/bpf
+	$(INSTALL_DATA) $(PKG_BUILD_DIR)/tcp_in_udp_tc.o $(1)/usr/lib/bpf
+endef
+
+$(eval $(call BuildPackage,tcp-in-udp))