Kernel: T4022: add RTSP netfilter helper kernel module

packages/linux-kernel/.gitignore

@@ -7,6 +7,7 @@
 /vyos-drivers-intel*
 /vyos-drivers-realtek*
 /ovpn-dco
+/nat-rtsp
 /jool*
 /qat*
 /QAT*

packages/linux-kernel/Jenkinsfile

@@ -69,6 +69,11 @@ def pkgList = [
     ['name': 'ovpn-dco','scmCommit': 'v0.2.20231117',
      'scmUrl': 'https://github.com/OpenVPN/ovpn-dco',
      'buildCmd': 'cd ..; ./build-openvpn-dco.sh'],
+
+    // RTSP netfilter helper
+    ['name': 'nat-rtsp', 'scmCommit': '475af0a',
+     'scmUrl': 'https://github.com/maru-sama/rtsp-linux.git',
+     'buildCmd': 'cd ..; ./build-nat-rtsp.sh'],
 ]
 
 // Start package build using library function from https://github.com/vyos/vyos-build

packages/linux-kernel/build-nat-rtsp.sh

@@ -0,0 +1,38 @@
+#!/bin/sh
+CWD=$(pwd)
+KERNEL_VAR_FILE=${CWD}/kernel-vars
+
+SRC=${CWD}/nat-rtsp
+if [ ! -d ${SRC} ]; then
+    echo "nat-rtsp source not found"
+    exit 1
+fi
+
+if [ ! -f ${KERNEL_VAR_FILE} ]; then
+    echo "Kernel variable file '${KERNEL_VAR_FILE}' does not exist, run ./build_kernel.sh first"
+    exit 1
+fi
+
+. ${KERNEL_VAR_FILE}
+
+cd ${SRC} && make KERNELDIR=$KERNEL_DIR
+
+# Copy binary to package directory
+DEBIAN_DIR=tmp/lib/modules/${KERNEL_VERSION}${KERNEL_SUFFIX}/extra
+mkdir -p ${DEBIAN_DIR}
+cp nf_conntrack_rtsp.ko nf_nat_rtsp.ko ${DEBIAN_DIR}
+
+DEBIAN_POSTINST="${CWD}/vyos-nat-rtsp.postinst"
+echo "#!/bin/sh" > ${DEBIAN_POSTINST}
+echo "/sbin/depmod -a ${KERNEL_VERSION}${KERNEL_SUFFIX}" >> ${DEBIAN_POSTINST}
+
+# Build Debian Package
+fpm --input-type dir --output-type deb --name nat-rtsp \
+    --version $(git describe --tags --always) --deb-compression gz \
+    --maintainer "VyOS Package Maintainers <maintainers@vyos.net>" \
+    --description "Connection tracking and NAT support for RTSP" \
+    --depends linux-image-${KERNEL_VERSION}${KERNEL_SUFFIX} \
+    --after-install ${DEBIAN_POSTINST} \
+    --license "GPL2" --chdir tmp
+
+mv *.deb ..