Fix scriptlet to reenable unit when obsolete wantedbys are removed.

Also improve tests and add Tox for mypy and pytest.

.gitignore

@@ -9,3 +9,5 @@ pkgs/
 build
 *.egg-info
 src/*.service
+.mypy_cache
+.tox

Jenkinsfile

@@ -1,4 +1,5 @@
 // https://github.com/Rudd-O/shared-jenkins-libraries
 @Library('shared-jenkins-libraries@master') _
 
-genericFedoraRPMPipeline()
+
+genericFedoraRPMPipeline(null, null, null, null, TestStrategySkipTests())

Makefile

@@ -11,12 +11,12 @@ src/qubes-routing-manager.service: src/qubes-routing-manager.service.in
 
 ROOT_DIR := $(shell dirname $(realpath $(firstword $(MAKEFILE_LIST))))
 
-.PHONY: clean dist rpm srpm install-template install-dom0
+.PHONY: clean dist rpm srpm install-template install-dom0 test
 
 clean:
 	cd $(ROOT_DIR) || exit $$? ; find -name '*.pyc' -o -name '*~' -print0 | xargs -0 rm -f
 	cd $(ROOT_DIR) || exit $$? ; rm -rf *.tar.gz *.rpm
-	cd $(ROOT_DIR) || exit $$? ; rm -rf *.egg-info build
+	cd $(ROOT_DIR) || exit $$? ; rm -rf *.egg-info build .mypy_cache
 
 dist: clean
 	@which rpmspec || { echo 'rpmspec is not available.  Please install the rpm-build package with the command `dnf install rpm-build` to continue, then rerun this step.' ; exit 1 ; }
@@ -32,12 +32,16 @@ rpm: dist
 	cd $(ROOT_DIR) ; mv -f builddir.rpm/*/* . && rm -rf builddir.rpm
 
 install-template: all
+	PYTHONDONTWRITEBYTECODE=1 python3 routingmanagersetup.py install $(PYTHON_PREFIX_ARG) -O0 --root $(DESTDIR)
 	install -Dm 755 src/qubes-routing-manager -t $(DESTDIR)/$(SBINDIR)/
 	sed -i "s,^#!.*,#!$(PYTHON)," $(DESTDIR)/$(SBINDIR)/qubes-routing-manager
 	install -Dm 644 src/qubes-routing-manager.service -t $(DESTDIR)/$(UNITDIR)/
 
 # Python 3 is always used for Qubes admin package.
 install-dom0:
-	PYTHONDONTWRITEBYTECODE=1 python3 setup.py install $(PYTHON_PREFIX_ARG) -O0 --root $(DESTDIR)
+	PYTHONDONTWRITEBYTECODE=1 python3 networkserversetup.py install $(PYTHON_PREFIX_ARG) -O0 --root $(DESTDIR)
 
 install: install-dom0 install-template
+
+test:
+	tox --current-env

README.md

@@ -1,22 +1,23 @@
 # Qubes network server
 
-This software lets you turn your [Qubes OS 4.0](https://www.qubes-os.org/) machine into
+This software lets you turn your [Qubes OS 4.2](https://www.qubes-os.org/) machine into
 a network server, enjoying all the benefits of Qubes OS (isolation, secure
 inter-VM process communication, ease of use) with none of the drawbacks
 of setting up your own Xen server.
 
-**Note**: this software only supports release 4.0 of Qubes OS.  For Qubes OS release 3.2 support,
-please see `release-3.2` branch.  For Qubes OS release 4.1 support, please see `r4.1 branch`.
+This release is only intended for use with Qubes OS 4.2.  Older Qubes OS releases
+will not support it.  For Qubes OS 4.1, check branch `r4.1`.
+
+**Important note about upgrades**: when you upgrade your system from Qubes OS 4.1 to
+Qubes OS 4.2, if you have this package installed in your template, the template will
+likely **fail to update**.  Please consult [our upgrade instructions](doc/distupgrade.md)
+for information on how to proceed.
 
 ## Why?
 
-Qubes OS is a magnificent operating system, but there are so many use cases that its networking
-model cannot crack:
+Qubes OS is a magnificent operating system.  That said, there are many use cases its networking
+model does not work well for:
 
-* As an automated integration testing system.  Qubes OS would be
-  phenomenal for this, and its automation tools would make it
-  extremely easy to bring up and tear down entire environments.
-  If only those environments could network with each other securely!
 * Remote management of Qubes OS instances.  Vanilla Qubes OS cannot
   easily be managed remotely.  A better networking model would allow
   for orchestration tools — such as
@@ -25,8 +26,12 @@ model cannot crack:
   within each VM.
 * Anything that involves a secure server, serving data to people or
   machines, simply cannot be done under vanilla Qubes OS.
+* As an automated integration testing system.  Qubes OS would be
+  phenomenal for this, and its automation tools would make it
+  extremely easy to bring up and tear down entire environments.
+  If only those environments could network with each other securely!
 
-## Enhanced networking model
+### The traditional Qubes networking model
 
 The traditional Qubes OS networking model contemplates a client-only
 use case.  User VMs (AppVMs or StandaloneVMs) are attached to ProxyVMs,
@@ -34,26 +39,32 @@ which give the user control over outbound connections taking place from
 user VMs.  ProxyVMs in turn attach to NetVMs, which provide outbound
 connectivity for ProxyVMs and other user VMs alike.
 
-![Standard Qubes OS network model](./doc/Standard Qubes OS network model.png)
+![Standard Qubes OS network model](./doc/Standard%20Qubes%20OS%20network%20model.png)
 
 No provision is made for running a server in a virtualized environment,
 such that the server's ports are accessible by (a) other VMs (b) machines
-beyond the perimeter of the NetVM.  To the extent that such a thing is
-possible, it is only possible by painstakingly maintaining firewall rules
-for multiple VMs, which need to carefully override the existing firewall
-rules, and require careful thought not to open the system to unexpected
-attack vectors.  The Qubes OS user interface provides no help either.
+beyond the perimeter of the NetVM.  By default, firewall rules in NetVMs
+prevent traffic from reaching any VM attached to them.  Furthermore, even
+with custom, permissive firewall rules, the IP addresses of VMs attached
+to any NetVM are not visible "on the other side of the NetVM", so firewall
+rules can only help with something like DNAT.  Finally, such custom firewalls
+require careful thought not to open the system to unexpected attack vectors.
+The Qubes OS user interface provides no means to set this up either.
 
-Qubes network server changes all that.
+### The Qubes network server networking model
 
-![Qubes network server model](./doc/Qubes network server model.png)
+Qubes network server builds on the Qubes security model and enhances it
+to optionally permit traffic to user VMs.
+
+![Qubes network server model](./doc/Qubes%20network%20server%20model.png)
 
 With the Qubes network server software, it becomes possible to make
 network servers in user VMs available to other machines, be them
 peer VMs in the same Qubes OS system or machines connected to
 a physical link shared by a NetVM.  Those network server VMs also
 obey the Qubes OS outbound firewall rules controls, letting you run
-services with outbound connections restricted.
+services with outbound connections restricted using the standard Qubes OS
+firewall system.
 
 This is all, of course, opt-in, so the standard Qubes OS network security
 model remains in effect until you decide to enable the feature on any
@@ -66,44 +77,62 @@ to machines on the same network as the NetVM.
 
 ## How to use this software
 
-Once installed (see below), usage of the software is straightforward.
+Once installed (**see below for installation instructions**), usage of
+the software is straightforward.
 
-These sample instructions assume you already have an AppVM VM set up,
-named `testvm`, and that your `sys-net` VM is attached to a network with
-subnet `192.168.16.0/24`.
+These sample instructions assume:
 
-First, attach the VM you want to expose to the network
+* the software is properly installed (see below),
+* you understand the distinction between dom0 and qubes,
+* you already have an AppVM VM set up, named `testvm`, and
+* your `sys-net` VM is attached to a network with subnet `192.168.16.0/24`
+  — this, of course, may vary depending on your local router configuration.
+
+*Do not proceed any further if you do not yet meet these requirements.*
+  
+First, **attach** the VM you want to expose to the network
 to a NetVM that has an active network connection:
 
 `qvm-prefs -s testvm netvm sys-net`
 
-Then, set an IP address on the VM:
+Set an **IP** address on `testvm` belonging to the same LAN as `sys-net`:
 
 `qvm-prefs -s testvm ip 192.168.16.25`
 
-(The step above requires you restart the `testvm` VM if it was running.)
+**Restart** the `testvm` VM if it was already running.
 
-Then, to enable the network server feature for your `testvm` VM, all you have
-to do in your AdminVM (`dom0`) is run the following command:
+**Configure** routing method; to enable the network server feature for
+your `testvm` VM, all you have to do in your AdminVM (`dom0`) is run
+the following command:
 
 `qvm-features testvm routing-method forward`
 
 Now `testvm` is exposed to the network with address `192.168.16.25`, as well
 as to other VMs attached to `NetVM`.
 
-Do note that `testvm` will have the standard Qubes OS firewall rules stopping
-inbound traffic.  To solve that issue, you can
-[use the standard `rc.local` Qubes OS mechanism to alter the firewall rules](https://www.qubes-os.org/doc/firewall/#where-to-put-firewall-rules)
-in your `testvm` AppVM.
+Finally, adjust **input firewall rules** on `testvm` to permit traffic coming from
+machines in your LAN.  `testvm` will have the standard Qubes OS firewall
+rules stopping inbound traffic.  To solve that issue, you can use a sample
+rule in `testvm`:
+
+```
+sudo nft add rule qubes custom-input ip saddr 192.168.16.0/24 ct state new,established,related counter accept
+```
+
+You can make these rules persistent by [following instructions on the Qubes
+OS firewall documentation page](https://www.qubes-os.org/doc/firewall/#enabling-networking-between-two-qubes).
+Note that you do not need to change the `custom-forward` chain at all
+on any qube -- Qubes network server manages that for you transparently
+in your `NetVM`.
 
 Here are documents that will help you take advantage of Qubes network server:
 
 * [Setting up your first server](doc/Setting up your first server.md)
 * [Setting up an SSH server](doc/Setting up an SSH server.md)
 
-## Installation
+## Setup
 
-Installation consists of two steps:
+Package installation consists of two steps (**the package creation instructions are below**):
 
 1. Deploy the `qubes-core-admin-addon-network-server` RPM to your `dom0`.
 2. Deploy the `qubes-network-server` RPM to the TemplateVM backing your
@@ -122,30 +151,38 @@ a terminal in your NetVM, then typing the following:
 systemctl status qubes-routing-manager.service
 ```
 
-The routing manager should show as `enabled` and `active` in the terminal output.
+The routing manager should show as `enabled` and `active` in the terminal
+output, with no errors.  You can now follow the usage instructions above.
 
 ### How to build the packages to install
 
 You will first build the `qubes-core-admin-addon-network-server` RPM.
 
 To build this package, you will need to use a `chroot` jail containing
-a Fedora installation of the exact same release as your `dom0` (Fedora 25
-for Qubes release 4.0, Fedora 31 for Qubes release 4.1).
+a Fedora installation of the exact same release as your `dom0` (Fedora 37
+for Qubes 4.2).  You can do this using `toolbox` (for maximum safety
+within a disposable qube):
 
-Copy the source of the package to your `chroot`.  Then start a shell in
-your `chroot`, and type `make rpm`.  You may have to install some packages
-in your `chroot` -- use `dnf install git rpm-build make coreutils tar gawk findutils systemd systemd-rpm-macros`
-to get the minimum dependency set installed.
+```
+dnf install -y toolbox
+toolbox create -r 37
+toolbox enter fedora-toolbox-37
+# Bam!  You have a shell in an isolated Fedora 37 instance now.
+```
 
-Once built, in the source directory you will find the RPM built for the
-exact release of Qubes you need.
+Within the toolbox, all your normal files from your home directory are
+visible.  Change into the directory that contains this source code,
+then type `make rpm`.  You may have to install some packages within your
+toolbox -- use `dnf install git rpm-build make coreutils tar gawk findutils systemd systemd-rpm-macros`
+to get the minimum dependency set installed.  Don't worry -- nothing within
+the toolbox affects
 
-Alternatively, you may first create a source RPM using `make srpm` on your
-regular workstation, then use `mock` to rebuild the source RPM produced
-in the source directory, using a Fedora release compatible with your `dom0`.
+Once built, in the source directory you will find the
+`qubes-core-admin-addon-network-server` RPM built for your dom0.
 
-To build the `qubes-network-server` RPM, you can use a DisposableVM running
-the same Fedora release as your NetVM.  Build said package as follows:
+To build the `qubes-network-server` RPM that goes in your template, you
+can simply use a DisposableVM running the same Fedora release as your NetVM.
+Build said package as follows:
 
 ```
 # Dependencies
@@ -157,8 +194,8 @@ make rpm
 ```
 
 The process will output a `qubes-network-server-*.noarch.rpm` in the
-directory where it ran.  Fish it out and save it into the VM where you'll
-install it.
+directory where it ran.  Fish it out and copy it into the template where
+you'll install it.
 
 You can power off the DisposableVM now.
 

build.parameters

@@ -0,0 +1 @@
+["QUBES_RELEASES": "4.2"]

doc/Setting up an SSH server.md

@@ -100,4 +100,4 @@ to your Qubes OS server.  You are also able to run commands on the
 `exp-ssh` VM, directly from your manager machine.
 
 Should you want to run commands on *other* VMs of your Qubes OS server,
-then learn how to [enable remote management of your Qubes network server](https://github.com/Rudd-O/ansible-qubes/tree/master/doc/Remote management of Qubes OS servers.md).
+then learn how to [enable remote management of your Qubes network server](https://github.com/Rudd-O/ansible-qubes/tree/master/doc/Remote%20management%20of%20Qubes%20OS%20servers.md).

doc/Setting up your first server.md

@@ -5,13 +5,14 @@ is meant to be a standalone VM that contains files, being served by
 a running HTTP server (port 80) within it.  This VM is attached to a
 NetVM `sys-net`, with IP address `192.168.1.4` on a local network
 `192.168.1.0/24`.  Our goal will be to make `httpserver` accessible
-to your laptop on the same physical network, which we'll assume has
-IP address `192.168.1.8`.
+to your client laptop on the same physical network, which we'll
+assume has IP address `192.168.1.8`.
 
 ##Assign a static address
 
 First step is to assign an address — let's make it `192.168.1.6` —
-to `httpserver`:
+to `httpserver` (of course, you should make sure that this IP
+address isn't used by any other equipment in your network):
 
 ```
 qvm-prefs -s httpserver ip 192.168.1.6

doc/distupgrade.md

@@ -0,0 +1,64 @@
+# How to upgrade a Qubes network server from Qubes OS 4.1 to Qubes OS 4.2
+
+The [standard instructions to upgrade Qubes OS systems](https://www.qubes-os.org/doc/upgrade/4.2/)
+will fail to work.  The instructions tell you to run something to the effect of:
+
+```
+qubes-dist-upgrade --all-pre-reboot <other flags>
+```
+
+then reboot, then run:
+
+```
+qubes-dist-upgrade --all-post-reboot <other flags>
+```
+
+The pre-reboot phase will fail if run without the following precautions.
+
+## Step by step instructions
+
+First, build a `qubes-network-server` RPM with the instructions provided
+by this package's [README.md](../README.md) file.  Then, for each template
+where `qubes-network-server` is installed, deposit your build of the
+`qubes-network-server` RPM in a folder `/root/update` of the template,
+and run the command `createrepo_c /root/update` (you may have to install
+package `createrepo_c` via `dnf` to run it).
+
+Now build a `qubes-core-admin-addon-network-server` package for your dom0,
+then copy the file to your profile directory into dom0.  Remember this
+package has to be built *in the same Fedora release (37)* as the Qubes OS
+4.2 dom0 (the `toolbox` command in a disposable qube is handy for this!).
+
+Now open the file `/etc/dnf/dnf.conf` on every template qube where you
+did the above, then add an `exclude=qubes-network-server` setting under
+its `[main]` section.
+
+Remove the currently-installed `qubes-core-admin-addon-network-server`
+package from your dom0 (using `dnf remove`).
+
+Run the pre-reboot phase.
+
+Install the recently-built `qubes-core-admin-addon-network-server` package
+into dom0 (using `dnf install` with the path to the RPM file).
+
+Reboot.
+
+Before running the post-reboot phase, remove the setting you added to the
+`dnf.conf` file of each template you modified.  Finally, add the file
+`/etc/yum.repos.d/local.repo` with the following contents:
+
+```
+[local]
+name=Local packages
+baseurl=file:///root/update
+enabled=1
+gpgcheck=0
+metadata_expire=15
+```
+
+Now run the post-reboot phase.  The template upgrade should succeed now.
+
+To finalize, delete folder `/root/update` and file `/etc/yum.repos.d/local.repo`
+from every template that has it.
+
+You are now updated to Qubes OS 4.2 and `qubes-network-server` is ready.

networkserversetup.py

@@ -0,0 +1,26 @@
+import os
+import setuptools
+
+if __name__ == "__main__":
+    version = (
+        open(os.path.join(os.path.dirname(__file__), "qubes-network-server.spec"))
+        .read()
+        .strip()
+    )
+    version = [v for v in version.splitlines() if v.startswith("Version:")][0]
+    version = version.split()[-1]
+    setuptools.setup(
+        name="qubesnetworkserver",
+        version=version,
+        author="Manuel Amador (Rudd-O)",
+        author_email="rudd-o@rudd-o.com",
+        description="Qubes network server dom0 component",
+        license="GPL2+",
+        url="https://github.com/Rudd-O/qubes-network-server",
+        packages=("qubesnetworkserver",),
+        entry_points={
+            "qubes.ext": [
+                "qubesnetworkserver = qubesnetworkserver:QubesNetworkServerExtension",
+            ],
+        },
+    )

qubes-network-server.spec

@@ -3,7 +3,7 @@
 %define mybuildnumber %{?build_number}%{?!build_number:1}
 
 Name:           qubes-network-server
-Version:        0.0.15
+Version:        0.1.6
 Release:        %{mybuildnumber}%{?dist}
 Summary:        Turn your Qubes OS into a network server
 BuildArch:      noarch
@@ -16,27 +16,18 @@ BuildRequires:  make
 BuildRequires:  coreutils
 BuildRequires:  tar
 BuildRequires:  findutils
-%if 0%{?fedora} < 31
-BuildRequires:  python2
-BuildRequires:  python2-rpm-macros
-%global pythoninterp %{_bindir}/python2
-%else
 BuildRequires:  python3
 BuildRequires:  python3-rpm-macros
-%global pythoninterp %{_bindir}/python3
-%endif
-
-%if 0%{?fedora} > 29
 BuildRequires:  systemd-rpm-macros
-%else
-%global _presetdir %{_prefix}/lib/systemd/system-preset
-%global _unitdir %{_prefix}/lib/systemd/system
-%endif
+BuildRequires:  python3-tox-current-env
+BuildRequires:  python3-mypy
+BuildRequires:  python3-pytest
 
-Requires:       qubes-core-agent-networking >= 4.0.51-1
-Conflicts:      qubes-core-agent-networking >= 4.1
-Requires:       python2
-Requires:       python2-qubesdb
+Requires:       qubes-core-agent-networking >= 4.2
+Conflicts:      qubes-core-agent < 4.2
+Requires:       python3
+Requires:       python3-qubesdb
+Requires:       nftables
 
 %description
 This package lets you turn your Qubes OS into a network server.  Install this
@@ -58,8 +49,8 @@ BuildRequires:  python3-rpm-macros
 BuildRequires:  python3-setuptools
 
 Requires:       python3
-Requires:       qubes-core-dom0 >= 4.0.49-1
-Conflicts:      qubes-core-dom0 >= 4.1
+Requires:       qubes-core-dom0 >= 4.2
+Conflicts:      qubes-core-dom0 < 4.2
 
 %description -n qubes-core-admin-addon-network-server
 This package lets you turn your Qubes OS into a network server.  Install this
@@ -74,27 +65,52 @@ this software.
 
 %build
 # variables must be kept in sync with install
-make DESTDIR=$RPM_BUILD_ROOT SBINDIR=%{_sbindir} UNITDIR=%{_unitdir} PYTHON=%{pythoninterp}
+make DESTDIR=$RPM_BUILD_ROOT SBINDIR=%{_sbindir} UNITDIR=%{_unitdir} PYTHON=%{__python3}
 
 %install
 rm -rf $RPM_BUILD_ROOT
 # variables must be kept in sync with build
-make install DESTDIR=$RPM_BUILD_ROOT SBINDIR=%{_sbindir} UNITDIR=%{_unitdir} PYTHON=%{pythoninterp}
+make install DESTDIR=$RPM_BUILD_ROOT SBINDIR=%{_sbindir} UNITDIR=%{_unitdir} PYTHON=%{__python3}
 mkdir -p "$RPM_BUILD_ROOT"/%{_presetdir}
 echo 'enable qubes-routing-manager.service' > "$RPM_BUILD_ROOT"/%{_presetdir}/75-%{name}.preset
 
+%check
+tox --current-env
+
 %files
 %attr(0755, root, root) %{_sbindir}/qubes-routing-manager
+%attr(0644, root, root) %{python3_sitelib}/qubesroutingmanager/*
+%{python3_sitelib}/qubesroutingmanager-*.egg-info
 %attr(0644, root, root) %{_presetdir}/75-%{name}.preset
 %config %attr(0644, root, root) %{_unitdir}/qubes-routing-manager.service
 %doc README.md TODO
 
-%files -n       qubes-core-admin-addon-network-server
+%files -n     qubes-core-admin-addon-network-server
 %attr(0644, root, root) %{python3_sitelib}/qubesnetworkserver/*
 %{python3_sitelib}/qubesnetworkserver-*.egg-info
 
 %post
-%systemd_post qubes-routing-manager.service
+%systemd_post  qubes-routing-manager.service
+
+%posttrans
+# Remove old unit enablement paths.
+reenable=0
+if [ -h %{_sysconfdir}/systemd/system/multi-user.target.wants/qubes-routing-manager.service ]
+then
+    reenable=1
+    rm -f %{_sysconfdir}/systemd/system/multi-user.target.wants/qubes-routing-manager.service
+fi
+if [ -h %{_sysconfdir}/systemd/system/qubes-iptables.service.wants/qubes-routing-manager.service ]
+then
+    reenable=1
+    rm -f %{_sysconfdir}/systemd/system/qubes-iptables.service.wants/qubes-routing-manager.service
+fi
+if [ $reenable = 1 ]
+then
+    mkdir -p %{_sysconfdir}/systemd/system/qubes-network.service.wants
+    ln -sf %{_unitdir}/qubes-routing-manager.service %{_sysconfdir}/systemd/system/qubes-network.service.wants/qubes-routing-manager.service
+fi
+exit 0
 
 %preun
 %systemd_preun qubes-routing-manager.service
@@ -102,19 +118,11 @@ echo 'enable qubes-routing-manager.service' > "$RPM_BUILD_ROOT"/%{_presetdir}/75
 %postun
 %systemd_postun_with_restart qubes-routing-manager.service
 
-%post -n         qubes-core-admin-addon-network-server
-%if 0%{?fedora} > 29
+%post -n      qubes-core-admin-addon-network-server
 %systemd_post qubesd.service
-%else
-systemctl try-restart qubesd.service
-%endif
 
-%postun -n       qubes-core-admin-addon-network-server
-%if 0%{?fedora} > 29
+%postun -n    qubes-core-admin-addon-network-server
 %systemd_postun_with_restart qubesd.service
-%else
-systemctl try-restart qubesd.service
-%endif
 
 %changelog
 * Mon Apr 13 2020 Manuel Amador (Rudd-O) <rudd-o@rudd-o.com>

qubesnetworkserver/__init__.py

@@ -1,14 +1,27 @@
 import qubes.ext
-import qubes.vm.templatevm
+
+
+def l(text, *parms):
+    return  # This exists only to debug.
+    if parms:
+        text = text % parms
+    import sys
+
+    print("nsext:", text, file=sys.stderr)
+    sys.stderr.flush()
+
+
+l("loaded")
 
 
 class QubesNetworkServerExtension(qubes.ext.Extension):
-
     def shutdown_routing_for_vm(self, netvm, appvm):
+        l("shutdown routing for vm %s %s", netvm, appvm)
         self.reload_routing_for_vm(netvm, appvm, True)
 
     def reload_routing_for_vm(self, netvm, appvm, shutdown=False):
-        '''Reload the routing method for the VM.'''
+        """Reload the routing method for the VM."""
+        l("reload routing for vm %s %s shutdown %s", netvm, appvm, shutdown)
         if not netvm.is_running():
             return
         for addr_family in (4, 6):
@@ -19,7 +32,7 @@ class QubesNetworkServerExtension(qubes.ext.Extension):
             self.setup_forwarding_for_vm(netvm, appvm, ip, remove=shutdown)
 
     def setup_forwarding_for_vm(self, netvm, appvm, ip, remove=False):
-        '''
+        """
         Record in Qubes DB that the passed VM may be meant to have traffic
         forwarded to and from it, rather than masqueraded from it and blocked
         to it.
@@ -35,54 +48,54 @@ class QubesNetworkServerExtension(qubes.ext.Extension):
 
         If `remove` is True, then we remove the respective routing method from
         the Qubes DB instead.
-        '''
+        """
+        l("setup forwarding for vm vm %s %s %s remove %s", netvm, appvm, ip, remove)
         if ip is None:
             return
         routing_method = appvm.features.check_with_template(
-            'routing-method', 'masquerade'
+            "routing-method", "masquerade"
         )
-        base_file = '/qubes-routing-method/{}'.format(ip)
+        base_file = "/qubes-routing-method/{}".format(ip)
         if remove:
             netvm.untrusted_qdb.rm(base_file)
-        elif routing_method == 'forward':
-            netvm.untrusted_qdb.write(base_file, 'forward')
+        elif routing_method == "forward":
+            netvm.untrusted_qdb.write(base_file, "forward")
         else:
-            netvm.untrusted_qdb.write(base_file, 'masquerade')
+            netvm.untrusted_qdb.write(base_file, "masquerade")
 
     @qubes.ext.handler(
-        'domain-feature-set:routing-method',
-        'domain-feature-delete:routing-method',
+        "domain-feature-set:routing-method",
+        "domain-feature-delete:routing-method",
     )
-    def on_routing_method_changed(
-            self,
-            vm,
-            ignored_feature,
-            **kwargs
-    ):
+    def on_routing_method_changed(self, vm, ignored_feature, **kwargs):
         # pylint: disable=no-self-use,unused-argument
-        if 'oldvalue' not in kwargs or kwargs.get('oldvalue') != kwargs.get('value'):
+        l("routing method changed %s", vm)
+        if "oldvalue" not in kwargs or kwargs.get("oldvalue") != kwargs.get("value"):
             if vm.netvm:
                 self.reload_routing_for_vm(vm.netvm, vm)
 
-    @qubes.ext.handler('domain-qdb-create')
+    @qubes.ext.handler("domain-qdb-create")
     def on_domain_qdb_create(self, vm, event, **kwargs):
-        ''' Fills the QubesDB with firewall entries. '''
+        """Fills the QubesDB with firewall entries."""
         # pylint: disable=unused-argument
+        l("domain create %s %s", vm, event)
         if vm.netvm:
             self.reload_routing_for_vm(vm.netvm, vm)
 
-    @qubes.ext.handler('domain-start')
+    @qubes.ext.handler("domain-start")
     def on_domain_started(self, vm, event, **kwargs):
         # pylint: disable=unused-argument
+        l("domain started %s %s", vm, event)
         try:
             for downstream_vm in vm.connected_vms:
                 self.reload_routing_for_vm(vm, downstream_vm)
         except AttributeError:
             pass
 
-    @qubes.ext.handler('domain-shutdown')
+    @qubes.ext.handler("domain-shutdown")
     def on_domain_shutdown(self, vm, event, **kwargs):
-       # pylint: disable=unused-argument
+        # pylint: disable=unused-argument
+        l("domain shutdown %s %s", vm, event)
         try:
             for downstream_vm in self.connected_vms:
                 self.shutdown_routing_for_vm(vm, downstream_vm)
@@ -90,9 +103,10 @@ class QubesNetworkServerExtension(qubes.ext.Extension):
             pass
         if vm.netvm:
             self.shutdown_routing_for_vm(vm.netvm, vm)
- 
-    @qubes.ext.handler('net-domain-connect')
+
+    @qubes.ext.handler("net-domain-connect")
     def on_net_domain_connect(self, vm, event):
         # pylint: disable=unused-argument
+        l("domain connect %s %s", vm, event)
         if vm.netvm:
             self.reload_routing_for_vm(vm.netvm, vm)

qubesroutingmanager/__init__.py

@@ -0,0 +1,379 @@
+#!/usr/bin/python3
+
+import json
+import logging
+import subprocess
+
+from typing import TypedDict, Any, cast, Literal, Union
+
+
+ADDRESS_FAMILIES = Union[Literal["ip"], Literal["ip6"]]
+
+
+class Chain(TypedDict):
+    name: str
+    family: str
+    table: str
+    handle: int
+    type: str
+    hook: str
+    prio: int
+    policy: str
+
+
+class Table(TypedDict):
+    family: str
+    name: str
+    handle: int
+
+
+class Metainfo(TypedDict):
+    version: str
+    release_name: str
+    json_schema_version: int
+
+
+class Rule(TypedDict):
+    family: str
+    table: str
+    chain: str
+    handle: int
+    expr: list[dict[str, Any]]
+
+
+class ChainContainer(TypedDict):
+    chain: Chain
+
+
+class MetainfoContainer(TypedDict):
+    metainfo: Metainfo
+
+
+class TableContainer(TypedDict):
+    table: Table
+
+
+class RuleContainer(TypedDict):
+    rule: Rule
+
+
+class NFTablesOutput(TypedDict):
+    nftables: list[ChainContainer | MetainfoContainer | TableContainer | RuleContainer]
+
+
+ADDRESS_FAMILY_IPV6 = "ip6"
+ADDRESS_FAMILY_IPV4 = "ip"
+TABLE_NAME = "qubes"
+FORWARD_CHAIN_NAME = "forward"
+POSTROUTING_CHAIN_NAME = "postrouting"
+ROUTING_MANAGER_CHAIN_NAME = "qubes-routing-manager"
+ROUTING_MANAGER_POSTROUTING_CHAIN_NAME = "qubes-routing-manager-postrouting"
+NFTABLES_CMD = "nft"
+
+
+def get_table(address_family: ADDRESS_FAMILIES, table: str) -> NFTablesOutput:
+    return cast(
+        NFTablesOutput,
+        json.loads(
+            subprocess.check_output(
+                [NFTABLES_CMD, "-n", "-j", "list", "table", address_family, table],
+                text=True,
+            )
+        ),
+    )
+
+
+def add_chain(address_family: ADDRESS_FAMILIES, table: str, chain: str) -> None:
+    subprocess.check_output(
+        [
+            NFTABLES_CMD,
+            "-n",
+            "-j",
+            "add",
+            "chain",
+            address_family,
+            table,
+            chain,
+        ],
+        text=True,
+    )
+
+
+def append_rule_at_end(
+    address_family: ADDRESS_FAMILIES, table: str, chain: str, *rest: str
+) -> None:
+    subprocess.check_output(
+        [
+            NFTABLES_CMD,
+            "-n",
+            "-j",
+            "add",
+            "rule",
+            address_family,
+            table,
+            chain,
+        ]
+        + list(rest),
+        text=True,
+    )
+
+
+def append_counter_at_end(
+    address_family: ADDRESS_FAMILIES, table: str, chain: str, *rest: str
+) -> None:
+    subprocess.check_output(
+        [
+            NFTABLES_CMD,
+            "-n",
+            "-j",
+            "add",
+            "rule",
+            address_family,
+            table,
+            chain,
+            "counter",
+        ]
+        + list(rest),
+        text=True,
+    )
+
+
+def _append_or_insert_rule(
+    where: Literal["add"] | Literal["insert"],
+    address_family: ADDRESS_FAMILIES,
+    table: str,
+    chain: str,
+    handle: int,
+    *rest: str,
+) -> None:
+    subprocess.check_output(
+        [
+            NFTABLES_CMD,
+            "-n",
+            "-j",
+            where,
+            "rule",
+            address_family,
+            table,
+            chain,
+            "position",
+            str(handle),
+        ]
+        + list(rest),
+        text=True,
+    )
+
+
+def append_rule_after(
+    address_family: ADDRESS_FAMILIES, table: str, chain: str, handle: int, *rest: str
+) -> None:
+    _append_or_insert_rule("add", address_family, table, chain, handle, *rest)
+
+
+def insert_rule_before(
+    address_family: ADDRESS_FAMILIES, table: str, chain: str, handle: int, *rest: str
+) -> None:
+    _append_or_insert_rule("insert", address_family, table, chain, handle, *rest)
+
+
+def delete_rule(
+    address_family: ADDRESS_FAMILIES, table: str, chain: str, handle: int
+) -> None:
+    subprocess.check_output(
+        [
+            NFTABLES_CMD,
+            "-n",
+            "-j",
+            "delete",
+            "rule",
+            address_family,
+            table,
+            chain,
+            "handle",
+            str(handle),
+        ],
+        text=True,
+    )
+
+
+def setup_plain_forwarding_for_address(source: str, enable: bool, family: int) -> None:
+    logging.info("Handling forwarding for address %s family %s.", source, family)
+
+    af = cast(
+        ADDRESS_FAMILIES,
+        ADDRESS_FAMILY_IPV6 if family == 6 else ADDRESS_FAMILY_IPV4,
+    )
+
+    # table ip qubes {
+    #     set downstream {
+    #         type ipv4_addr
+    #         elements = { 10.137.0.10, 10.250.4.13 }
+    #     }
+    #     ...
+    existing_table_output = get_table(af, TABLE_NAME)
+    existing_table_items = existing_table_output["nftables"]
+
+    existing_chains = [x["chain"] for x in existing_table_items if "chain" in x]  # type: ignore
+    existing_rules = [x["rule"] for x in existing_table_items if "rule" in x]  # type: ignore
+
+    try:
+        forward_chain = [x for x in existing_chains if x["name"] == FORWARD_CHAIN_NAME][
+            0
+        ]
+        postrouting_chain = [
+            x for x in existing_chains if x["name"] == POSTROUTING_CHAIN_NAME
+        ][0]
+    except IndexError:
+        logging.warn(
+            "No forward or postrouting chains in table %s, not setting up forwarding",
+            TABLE_NAME,
+        )
+        return
+
+    for chain_name in [
+        ROUTING_MANAGER_CHAIN_NAME,
+        ROUTING_MANAGER_POSTROUTING_CHAIN_NAME,
+    ]:
+        chain: None | Chain = None
+        try:
+            chain = [x for x in existing_chains if x["name"] == chain_name].pop()
+        except IndexError:
+            pass
+
+        if not chain:
+            logging.info(
+                "Adding %s chain to table %s and counter to chain",
+                chain_name,
+                TABLE_NAME,
+            )
+            add_chain(af, TABLE_NAME, chain_name)
+            append_counter_at_end(
+                af,
+                TABLE_NAME,
+                chain_name,
+            )
+
+    def is_oifgroup_2(rule):
+        return (
+            rule["chain"] == forward_chain["name"]
+            and len(rule["expr"]) == 3
+            and (
+                rule["expr"][0].get("match", {}).get("op") == "=="
+                and rule["expr"][0]
+                .get("match", {})
+                .get("left", {})
+                .get("meta", {})
+                .get("key")
+                == "oifgroup"
+                and rule["expr"][0].get("match", {}).get("right") == 2
+            )
+            and (rule["expr"][-1].get("drop", "not none") is None)
+        )
+
+    def is_postrouting_masquerade(rule):
+        return (
+            rule["chain"] == postrouting_chain["name"]
+            and len(rule["expr"]) == 1
+            and "masquerade" in rule["expr"][0]
+        )
+
+    for parent_chain, child_chain_name, previous_rule_detector, insertor in [
+        (
+            forward_chain,
+            ROUTING_MANAGER_CHAIN_NAME,
+            is_oifgroup_2,
+            insert_rule_before,
+        ),
+        (
+            postrouting_chain,
+            ROUTING_MANAGER_POSTROUTING_CHAIN_NAME,
+            is_postrouting_masquerade,
+            insert_rule_before,
+        ),
+    ]:
+        jump_rule: None | Rule = None
+        try:
+            jump_rule = [
+                x
+                for x in existing_rules
+                if x["chain"] == parent_chain["name"]
+                and x["family"] == af
+                and len(x["expr"]) == 1
+                and x["expr"][0].get("jump", {}).get("target") == child_chain_name
+            ].pop()
+        except IndexError:
+            pass
+
+        if not jump_rule:
+            try:
+                previous_rule = [
+                    x for x in existing_rules if previous_rule_detector(x)
+                ][0]
+            except IndexError:
+                logging.warn(
+                    "Cannot find appropriate previous rule in chain %s of table %s, not setting up forwarding",
+                    parent_chain["name"],
+                    TABLE_NAME,
+                )
+            logging.info(
+                "Adding rule to jump from chain %s to chain %s in table %s",
+                parent_chain["name"],
+                child_chain_name,
+                TABLE_NAME,
+            )
+            insertor(
+                af,
+                TABLE_NAME,
+                parent_chain["name"],
+                previous_rule["handle"],
+                "jump",
+                child_chain_name,
+            )
+
+    def detect_ip_rule(rule: Rule, chain_name: str, ip: str, mode: str):
+        return (
+            rule["chain"] == chain_name
+            and len(rule["expr"]) == 2
+            and rule["expr"][0].get("match", {}).get("op", {}) == "=="
+            and rule["expr"][0]["match"]
+            .get("left", {})
+            .get("payload", {})
+            .get("protocol", "")
+            == af
+            and rule["expr"][0]["match"]["left"]["payload"].get("field", "") == mode
+            and rule["expr"][0].get("match", {}).get("right", []) == ip
+            and "accept" in rule["expr"][1]
+        )
+
+    for chain_name, mode in [
+        (ROUTING_MANAGER_CHAIN_NAME, "daddr"),
+        (ROUTING_MANAGER_POSTROUTING_CHAIN_NAME, "saddr"),
+    ]:
+        address_rules = [
+            x for x in existing_rules if detect_ip_rule(x, chain_name, source, mode)
+        ]
+
+        if enable and not address_rules:
+            logging.info(
+                "Adding accept rule on chain %s for %s.",
+                chain_name,
+                source,
+            )
+            append_rule_at_end(
+                af,
+                TABLE_NAME,
+                chain_name,
+                af,
+                mode,
+                source,
+                "accept",
+            )
+        elif not enable and address_rules:
+            logging.info(
+                "Removing %s accept rules from chain %s for %s.",
+                len(address_rules),
+                chain_name,
+                source,
+            )
+            for rule in reversed(sorted(address_rules, key=lambda r: r["handle"])):
+                delete_rule(af, TABLE_NAME, chain_name, rule["handle"])

qubesroutingmanager/test_firewalling.py

@@ -0,0 +1,162 @@
+import os
+
+from unittest import mock
+from qubesroutingmanager import setup_plain_forwarding_for_address
+
+
+def get_fixture(name):
+    with open(os.path.join(os.path.dirname(__file__), "fixtures", name)) as f:
+        return f.read()
+
+
+def mock_collector(output: str):
+    final_args = []
+
+    class MockedPopen:
+        def __init__(self, args, **kwargs):
+            final_args.append(args[3:])
+            self.args = args
+            self.returncode = 0
+
+        def __enter__(self):
+            return self
+
+        def __exit__(self, exc_type, value, traceback):
+            pass
+
+        def communicate(self, input=None, timeout=None):
+            stdout = output
+            stderr = ""
+            self.returncode = 1
+            return stdout, stderr
+
+        def poll(self):
+            return 0
+
+    return final_args, MockedPopen
+
+
+def test_partial_add_completes_the_add():
+    got, MockedPopen = mock_collector(get_fixture("partially_added.json"))
+    expected = [
+        ["list", "table", "ip", "qubes"],
+        ["add", "chain", "ip", "qubes", "qubes-routing-manager-postrouting"],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager-postrouting",
+            "counter",
+        ],
+        [
+            "insert",
+            "rule",
+            "ip",
+            "qubes",
+            "postrouting",
+            "position",
+            "67",
+            "jump",
+            "qubes-routing-manager-postrouting",
+        ],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager-postrouting",
+            "ip",
+            "saddr",
+            "10.250.4.13",
+            "accept",
+        ],
+    ]
+    with mock.patch("subprocess.Popen", MockedPopen):
+        setup_plain_forwarding_for_address("10.250.4.13", True, 4)
+
+    assert got == expected
+
+
+def test_forward_rule_added_before_oifgroup_2():
+    got, MockedPopen = mock_collector(get_fixture("no_routing_manager.json"))
+    expected = [
+        ["list", "table", "ip", "qubes"],
+        ["add", "chain", "ip", "qubes", "qubes-routing-manager"],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager",
+            "counter",
+        ],
+        ["add", "chain", "ip", "qubes", "qubes-routing-manager-postrouting"],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager-postrouting",
+            "counter",
+        ],
+        [
+            "insert",
+            "rule",
+            "ip",
+            "qubes",
+            "forward",
+            "position",
+            "79",
+            "jump",
+            "qubes-routing-manager",
+        ],
+        [
+            "insert",
+            "rule",
+            "ip",
+            "qubes",
+            "postrouting",
+            "position",
+            "67",
+            "jump",
+            "qubes-routing-manager-postrouting",
+        ],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager",
+            "ip",
+            "daddr",
+            "10.250.4.13",
+            "accept",
+        ],
+        [
+            "add",
+            "rule",
+            "ip",
+            "qubes",
+            "qubes-routing-manager-postrouting",
+            "ip",
+            "saddr",
+            "10.250.4.13",
+            "accept",
+        ],
+    ]
+    with mock.patch("subprocess.Popen", MockedPopen):
+        setup_plain_forwarding_for_address("10.250.4.13", True, 4)
+
+    assert got == expected
+
+
+def test_forwarding_does_not_add_twice():
+    got, MockedPopen = mock_collector(get_fixture("fully_added.json"))
+    expected = [
+        ["list", "table", "ip", "qubes"],
+    ]
+    with mock.patch("subprocess.Popen", MockedPopen):
+        setup_plain_forwarding_for_address("10.250.4.13", True, 4)
+
+    assert got == expected

qubesroutingmanager/worker.py

@@ -0,0 +1,135 @@
+#!/usr/bin/python3
+
+"""
+This program reads the /qubes-firewall/{ip}/qubes-routing-method file
+for any firewall configuration, then configures the network to obey
+the routing method for the VM.  If the routing method is "masquerade",
+then nothing happens.  If, however, the routing method is "forward",
+then VM-specific rules are enacted in the VM's attached NetVM to allow
+traffic coming from other VMs and the outside world to reach this VM.
+"""
+
+import glob
+import logging
+import os
+import socket
+
+import qubesdb  # type: ignore
+
+from qubesroutingmanager import setup_plain_forwarding_for_address
+
+
+FORWARD_ROUTING_METHOD = "forward"
+
+
+def _s(v):
+    if isinstance(v, bytes):
+        return v.decode("utf-8")
+    return v
+
+
+class AdjunctWorker(object):
+    def __init__(self):
+        self.qdb = qubesdb.QubesDB()
+
+    @staticmethod
+    def is_ip6(addr):
+        return addr.count(":") > 0
+
+    def setup_proxy_arp_ndp(self, enabled, family):
+        # If any of the IP addresses is assigned the forward routing method,
+        # then enable proxy ARP/NDP on the upstream interfaces, so that the
+        # interfaces in question will impersonate the IP addresses in question.
+        # Ideally, this impersonation would be exclusively done for the
+        # specific IP addresses in question, but it is not clear to me how
+        # to cause this outcome to take place.
+        if family == 6:
+            globber = "/proc/sys/net/ipv6/conf/*/proxy_ndp"
+            name = "proxy NDP"
+        elif family == 4:
+            globber = "/proc/sys/net/ipv4/conf/*/proxy_arp"
+            name = "proxy ARP"
+        else:
+            return
+
+        if enabled:
+            action = "Enabling"
+            val = "1\n"
+        else:
+            action = "Disabling"
+            val = "0\n"
+
+        matches = glob.glob(globber)
+        for m in matches:
+            iface = m.split("/")[6]
+            if iface in ("all", "lo") or iface.startswith("vif"):
+                # No need to enable it for "all", or VIFs, or loopback.
+                continue
+            with open(m, "w+") as f:
+                oldval = f.read()
+                if oldval != val:
+                    logging.info("%s %s on interface %s.", action, name, iface)
+                    f.seek(0)
+                    f.write(val)
+
+    def handle_addr(self, addr):
+        # Setup plain forwarding for this specific address.
+        routing_method = _s(self.qdb.read("/qubes-routing-method/{}".format(addr)))
+        setup_plain_forwarding_for_address(
+            addr,
+            routing_method == FORWARD_ROUTING_METHOD,
+            6 if self.is_ip6(addr) else 4,
+        )
+
+        # Manipulate proxy ARP for all known addresses.
+        methods = [
+            (_s(k).split("/")[2], _s(v))
+            for k, v in self.qdb.multiread("/qubes-routing-method/").items()
+        ]
+        mmethods = {
+            4: [m[1] for m in methods if not self.is_ip6(m[0])],
+            6: [m[1] for m in methods if self.is_ip6(m[0])],
+        }
+        for family, methods in mmethods.items():
+            self.setup_proxy_arp_ndp(
+                FORWARD_ROUTING_METHOD in methods,
+                family,
+            )
+
+    def list_targets(self):
+        return set(_s(t).split("/")[2] for t in self.qdb.list("/qubes-routing-method/"))
+
+    def sd_notify(self, state):
+        """Send notification to systemd, if available"""
+        # based on sdnotify python module
+        if "NOTIFY_SOCKET" not in os.environ:
+            return
+        addr = os.environ["NOTIFY_SOCKET"]
+        if addr[0] == "@":
+            addr = "\0" + addr[1:]
+        try:
+            sock = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
+            sock.connect(addr)
+            sock.sendall(state.encode())
+        except BaseException:
+            # generally ignore error on systemd notification
+            pass
+
+    def main(self):
+        logging.basicConfig(level=logging.INFO)
+        self.qdb.watch("/qubes-routing-method/")
+        for source_addr in self.list_targets():
+            self.handle_addr(source_addr)
+        self.sd_notify("READY=1")
+        try:
+            for watch_path in iter(self.qdb.read_watch, None):
+                # ignore writing rules itself - wait for final write at
+                # source_addr level empty write (/qubes-firewall/SOURCE_ADDR)
+                watch_path = _s(watch_path)
+                if watch_path.count("/") != 2:
+                    continue
+                source_addr = watch_path.split("/")[2]
+                self.handle_addr(source_addr)
+        except OSError:  # EINTR
+            # signal received, don't continue the loop
+            return

routingmanagersetup.py

@@ -0,0 +1,21 @@
+import os
+import setuptools
+
+if __name__ == "__main__":
+    version = (
+        open(os.path.join(os.path.dirname(__file__), "qubes-network-server.spec"))
+        .read()
+        .strip()
+    )
+    version = [v for v in version.splitlines() if v.startswith("Version:")][0]
+    version = version.split()[-1]
+    setuptools.setup(
+        name="qubesroutingmanager",
+        version=version,
+        author="Manuel Amador (Rudd-O)",
+        author_email="rudd-o@rudd-o.com",
+        description="Qubes network server network qube (template) component",
+        license="GPL2+",
+        url="https://github.com/Rudd-O/qubes-network-server",
+        packages=("qubesroutingmanager",),
+    )

setup.py

@@ -1,24 +0,0 @@
-import os
-import setuptools
-
-if __name__ == '__main__':
-    version = open(os.path.join(os.path.dirname(__file__), 'qubes-network-server.spec')).read().strip()
-    version = [v for v in version.splitlines() if v.startswith("Version:")][0]
-    version = version.split()[-1]
-    setuptools.setup(
-        name='qubesnetworkserver',
-        version=version,
-        author='Manuel Amador (Rudd-O)',
-        author_email='rudd-o@rudd-o.com',
-        description='Qubes network server dom0 component',
-        license='GPL2+',
-        url='https://github.com/Rudd-O/qubes-network-server',
-
-        packages=('qubesnetworkserver',),
-
-        entry_points={
-            'qubes.ext': [
-                'qubesnetworkserver = qubesnetworkserver:QubesNetworkServerExtension',
-            ],
-        }
-    )

src/qubes-routing-manager

@@ -1,260 +1,8 @@
-#!/usr/bin/python2
-
-"""
-This program reads the /qubes-firewall/{ip}/qubes-routing-method file
-for any firewall configuration, then configures the network to obey
-the routing method for the VM.  If the routing method is "masquerade",
-then nothing happens.  If, however, the routing method is "forward",
-then VM-specific rules are enacted in the VM's attached NetVM to allow
-traffic coming from other VMs and the outside world to reach this VM.
-"""
-
-import glob
-import logging
-import os
-import socket
-import subprocess
-
-import qubesdb
-
-
-def _s(v):
-    if isinstance(v, bytes):
-        return v.decode("utf-8")
-    return v
-
-
-FORWARD_ROUTING_METHOD = "forward"
-
-
-class AdjunctWorker(object):
-    def __init__(self):
-        self.qdb = qubesdb.QubesDB()
-
-    @staticmethod
-    def is_ip6(addr):
-        return addr.count(":") > 0
-
-    def setup_plain_forwarding_for_address(self, source, enable, family):
-        def find_pos_of_first_rule(table, startswith):
-            rules = [n for n, l in enumerate(out) if l.startswith(startswith)]
-            if rules:
-                return rules[0]
-            return None
-
-        cmd = "ip6tables" if family == 6 else "iptables"
-        mask = "/128" if family == 6 else "/32"
-
-        def run_ipt(*args):
-            return subprocess.check_call([cmd, "-w"] + list(args))
-
-        out = subprocess.check_output(
-            [cmd + "-save"], universal_newlines=True
-        ).splitlines()
-
-        if enable:
-            # Create necessary prerouting chain.
-            if not find_pos_of_first_rule(out, ":PR-PLAIN-FORWARDING - "):
-                run_ipt("-t", "nat", "-N", "PR-PLAIN-FORWARDING")
-
-            # Route prerouting traffic to necessary chain.
-            if not find_pos_of_first_rule(out, "-A POSTROUTING -j PR-PLAIN-FORWARDING"):
-                rule_num = find_pos_of_first_rule(out, "-A POSTROUTING -j MASQUERADE")
-                if not rule_num:
-                    # This table does not contain the masquerading rule.
-                    # Accordingly, we will not do anything.
-                    return
-                first_rule_num = find_pos_of_first_rule(out, "-A POSTROUTING")
-                pos = rule_num - first_rule_num + 1
-                logging.info("Adding POSTROUTING chain PR-PLAIN-FORWARDING.")
-                run_ipt(
-                    "-t",
-                    "nat",
-                    "-I",
-                    "POSTROUTING",
-                    str(pos),
-                    "-j",
-                    "PR-PLAIN-FORWARDING",
-                )
-
-            # Create necessary forward chain.
-            if not find_pos_of_first_rule(out, ":PLAIN-FORWARDING - "):
-                run_ipt("-t", "filter", "-N", "PLAIN-FORWARDING")
-
-            # Route forward traffic to necessary chain.
-            if not find_pos_of_first_rule(out, "-A FORWARD -j PLAIN-FORWARDING"):
-                rule_num = find_pos_of_first_rule(
-                    out, "-A FORWARD -i vif+ -o vif+ -j DROP"
-                )
-                if not rule_num:
-                    # This table does not contain the masquerading rule.
-                    # Accordingly, we will not do anything.
-                    return
-                first_rule_num = find_pos_of_first_rule(out, "-A FORWARD")
-                pos = rule_num - first_rule_num + 1
-                logging.info("Adding FORWARD chain PLAIN-FORWARDING.")
-                run_ipt(
-                    "-t", "filter", "-I", "FORWARD", str(pos), "-j", "PLAIN-FORWARDING"
-                )
-
-        rule = find_pos_of_first_rule(
-            out, "-A PR-PLAIN-FORWARDING -s {}{} -j ACCEPT".format(source, mask)
-        )
-        if enable:
-            if rule:
-                pass
-            else:
-                logging.info(
-                    "Adding POSTROUTING rule to forward traffic from %s.", source
-                )
-                run_ipt(
-                    "-t",
-                    "nat",
-                    "-A",
-                    "PR-PLAIN-FORWARDING",
-                    "-s",
-                    "{}{}".format(source, mask),
-                    "-j",
-                    "ACCEPT",
-                )
-        else:
-            if rule:
-                first_rule = find_pos_of_first_rule(out, "-A PR-PLAIN-FORWARDING")
-                pos = rule - first_rule + 1
-                logging.info(
-                    "Removing POSTROUTING rule forwarding traffic from %s.", source
-                )
-                run_ipt("-t", "nat", "-D", "PR-PLAIN-FORWARDING", str(pos))
-            else:
-                pass
-
-        rule = find_pos_of_first_rule(
-            out, "-A PLAIN-FORWARDING -d {}{} -o vif+ -j ACCEPT".format(source, mask)
-        )
-        if enable:
-            if rule:
-                pass
-            else:
-                logging.info("Adding FORWARD rule to allow traffic to %s.", source)
-                run_ipt(
-                    "-t",
-                    "filter",
-                    "-A",
-                    "PLAIN-FORWARDING",
-                    "-d",
-                    "{}{}".format(source, mask),
-                    "-o",
-                    "vif+",
-                    "-j",
-                    "ACCEPT",
-                )
-        else:
-            if rule:
-                logging.info("Removing FORWARD rule allowing traffic to %s.", source)
-                first_rule = find_pos_of_first_rule(out, "-A PLAIN-FORWARDING")
-                pos = rule - first_rule + 1
-                run_ipt("-t", "filter", "-D", "PLAIN-FORWARDING", str(pos))
-            else:
-                pass
-
-    def setup_proxy_arp_ndp(self, enabled, family):
-        # If any of the IP addresses is assigned the forward routing method,
-        # then enable proxy ARP/NDP on the upstream interfaces, so that the
-        # interfaces in question will impersonate the IP addresses in question.
-        # Ideally, this impersonation would be exclusively done for the
-        # specific IP addresses in question, but it is not clear to me how
-        # to cause this outcome to take place.
-        if family == 6:
-            globber = "/proc/sys/net/ipv6/conf/*/proxy_ndp"
-            name = "proxy NDP"
-        elif family == 4:
-            globber = "/proc/sys/net/ipv4/conf/*/proxy_arp"
-            name = "proxy ARP"
-        else:
-            return
-
-        if enabled:
-            action = "Enabling"
-            val = "1\n"
-        else:
-            action = "Disabling"
-            val = "0\n"
-
-        matches = glob.glob(globber)
-        for m in matches:
-            iface = m.split("/")[6]
-            if iface in ("all", "lo") or iface.startswith("vif"):
-                # No need to enable it for "all", or VIFs, or loopback.
-                continue
-            with open(m, "w+") as f:
-                oldval = f.read()
-                if oldval != val:
-                    logging.info("%s %s on interface %s.", action, name, iface)
-                    f.seek(0)
-                    f.write(val)
-
-    def handle_addr(self, addr):
-        # Setup plain forwarding for this specific address.
-        routing_method = _s(self.qdb.read("/qubes-routing-method/{}".format(addr)))
-        self.setup_plain_forwarding_for_address(
-            addr,
-            routing_method == FORWARD_ROUTING_METHOD,
-            6 if self.is_ip6(addr) else 4,
-        )
-
-        # Manipulate proxy ARP for all known addresses.
-        methods = [
-            (_s(k).split("/")[2], _s(v))
-            for k, v in self.qdb.multiread("/qubes-routing-method/").items()
-        ]
-        mmethods = {
-            4: [m[1] for m in methods if not self.is_ip6(m[0])],
-            6: [m[1] for m in methods if self.is_ip6(m[0])],
-        }
-        for family, methods in mmethods.items():
-            self.setup_proxy_arp_ndp(
-                FORWARD_ROUTING_METHOD in methods, family,
-            )
-
-    def list_targets(self):
-        return set(_s(t).split("/")[2] for t in self.qdb.list("/qubes-routing-method/"))
-
-    def sd_notify(self, state):
-        """Send notification to systemd, if available"""
-        # based on sdnotify python module
-        if not "NOTIFY_SOCKET" in os.environ:
-            return
-        addr = os.environ["NOTIFY_SOCKET"]
-        if addr[0] == "@":
-            addr = "\0" + addr[1:]
-        try:
-            sock = socket.socket(socket.AF_UNIX, socket.SOCK_DGRAM)
-            sock.connect(addr)
-            sock.sendall(state.encode())
-        except:
-            # generally ignore error on systemd notification
-            pass
-
-    def main(self):
-        logging.basicConfig(level=logging.INFO)
-        self.qdb.watch("/qubes-routing-method/")
-        for source_addr in self.list_targets():
-            self.handle_addr(source_addr)
-        self.sd_notify("READY=1")
-        try:
-            for watch_path in iter(self.qdb.read_watch, None):
-                # ignore writing rules itself - wait for final write at
-                # source_addr level empty write (/qubes-firewall/SOURCE_ADDR)
-                watch_path = _s(watch_path)
-                if watch_path.count("/") != 2:
-                    continue
-                source_addr = watch_path.split("/")[2]
-                self.handle_addr(source_addr)
-        except OSError:  # EINTR
-            # signal received, don't continue the loop
-            return
+#!/usr/bin/python3
 
 
 if __name__ == "__main__":
+    from qubesroutingmanager.worker import AdjunctWorker
+
     w = AdjunctWorker()
     w.main()

src/qubes-routing-manager.service.in

@@ -1,13 +1,13 @@
 [Unit]
 Description=Configure the network to allow network server VMs
 Documentation=https://github.com/Rudd-O/qubes-network-server
-ConditionPathExists=/var/run/qubes-service/qubes-firewall
-After=qubes-firewall.service
-BindsTo=qubes-firewall.service
+After=qubes-network.service qubes-iptables.service
+BindsTo=qubes-iptables.service
+ConditionPathExists=/var/run/qubes-service/qubes-network
 
 [Service]
 Type=notify
 ExecStart=@SBINDIR@/qubes-routing-manager
 
 [Install]
-WantedBy=multi-user.target
+WantedBy=qubes-network.service

tox.ini

@@ -0,0 +1,10 @@
+[tox]
+envlist = basepython
+
+[testenv]
+deps =
+    pytest
+    mypy
+commands =
+    pytest -vv
+    mypy -p qubesroutingmanager