Compare commits

..

No commits in common. "main" and "v0.8.1" have entirely different histories.
main ... v0.8.1

47 changed files with 1453 additions and 2025 deletions

View File

@ -1,32 +0,0 @@
name: Main workflow
on:
pull_request:
push:
schedule:
# Prime the caches every Monday
- cron: 0 1 * * MON
jobs:
build:
strategy:
fail-fast: false
matrix:
os:
- ubuntu-latest
runs-on: ${{ matrix.os }}
steps:
- name: Checkout code
uses: actions/checkout@v4
- run: ./build-with.sh docker
- run: sh -exc 'if [ "$(sha256sum dist/qubes-firewall.xen)" = "$(cat qubes-firewall.sha256)" ]; then echo "SHA256 MATCHES"; else exit 42; fi'
- name: Upload Artifact
uses: actions/upload-artifact@v4
with:
name: qubes-firewall.xen
path: qubes-firewall.xen

View File

@ -1,42 +0,0 @@
name: ocamlformat
on: [push]
jobs:
format:
name: ocamlformat
strategy:
fail-fast: false
matrix:
ocaml-version: ["4.14.2"]
operating-system: [ubuntu-latest]
runs-on: ${{ matrix.operating-system }}
steps:
- name: Checkout code
uses: actions/checkout@v4
- name: Use OCaml ${{ matrix.ocaml-version }}
uses: ocaml/setup-ocaml@v3
with:
ocaml-compiler: ${{ matrix.ocaml-version }}
- name: Install ocamlformat
run: grep ^version .ocamlformat | cut -d '=' -f 2 | xargs -I V opam install ocamlformat=V
- name: Format code
run: git ls-files '*.ml' '*.mli' | xargs opam exec -- ocamlformat --inplace
- name: Check for modified files
id: git-check
run: echo "modified=$(if git diff-index --quiet HEAD --; then echo "false"; else echo "true"; fi)" >> $GITHUB_OUTPUT
- name: Commit and push changes
if: steps.git-check.outputs.modified == 'true'
run: |
git config --global user.name "Automated ocamlformat GitHub action, developed by robur.coop"
git config --global user.email "autoformat@robur.coop"
git commit -m "formatted code" .
git push

View File

@ -1,32 +0,0 @@
name: Main workflow
on:
pull_request:
push:
schedule:
# Prime the caches every Monday
- cron: 0 1 * * MON
jobs:
build:
strategy:
fail-fast: false
matrix:
os:
- ubuntu-latest
runs-on: ${{ matrix.os }}
steps:
- name: Checkout code
uses: actions/checkout@v4
- run: ./build-with.sh podman
- run: sh -exc 'if [ "$(sha256sum dist/qubes-firewall.xen)" = "$(cat qubes-firewall.sha256)" ]; then echo "SHA256 MATCHES"; else exit 42; fi'
- name: Upload Artifact
uses: actions/upload-artifact@v4
with:
name: qubes-firewall.xen
path: qubes-firewall.xen

View File

@ -1,3 +0,0 @@
version = 0.27.0
profile = conventional
parse-docstrings = true

View File

@ -1,89 +1,3 @@
### 0.9.4 (2025-02-10)
- Fix an issue when qubes-mirage-firewall is used a a mullvad AppVM client. If
our netvm does not reply to our ARP requests we can not construct the ethernet
header. However in Linux VMs, Qubes adds a default netvm address associated to
`fe:ff:ff:ff:ff:ff`, so if ARP fails, we fall back on that address.
(#213, @palainp, reported in the Qubes forum #212, reviewed by @hannesm)
### 0.9.3 (2025-01-04)
- Fix an issue when qubes-mirage-firewall is used along with *BSD sys-net
(#209, @palainp, reported in the Qubes forum #208, reviewed by @dinosaure)
### 0.9.2 (2024-10-16)
- Code refactoring and improvements (#197, @dinosaure)
- Build tooling updates: opam 2.2.1, solo5 0.9, mirage 4.8.1 (#199, #201, #202,
#203, @hannesm)
### 0.9.1 (2024-05-10)
- Drop astring dependency, update mirage-net-xen, and OCaml 4.14.2 -- the
latest LTS release (#193, @hannesm)
- Allow the firewall to use domains requests in rules (#193, @palainp,
reported in the Qubes forum, fix confirmed by @neoniobium)
### 0.9.0 (2024-04-24)
- Fix an incorrect free memory estimation (fix in mirage/ocaml-solo5#135
@palainp)
- Update to mirage 4.5.0, allowing openBSD to be used as netvm (#146 reported
by @Szewcson), and recover from a netvm change (#156 reported by @xaki-23)
(#178 @palainp)
### 0.8.6 (2023-11-08)
- Fix Docker build issue with newest SELinux policies (#183 @palainp, reported
by @Szewcson)
- Update build script (change to debian repositories, update debian image, update
opam-repository commit, set commit for opam-overlay and mirage-overlay) (#184
@palainp, reported by @ben-grande)
- Update disk usage value during local compilation (#186 @palainp, reported by
@ben-grande)
### 0.8.5 (2023-07-05)
- Remove memreport to Xen to avoid Qubes trying to get back some memory
(#176 @palainp)
- Use bookworm and snapshot.notset.fr debian packages for reproducibility
(#175 @palainp)
### 0.8.4 (2022-12-07)
- Fix remote denial of service due to excessive console output (#166 @burghardt,
fix in solo5/solo5#538 by @palainp)
- Use Ubuntu container for build, now GitHub action, ./build-with-docker.sh and
builds.robur.coop are synchronized (and result in the same artifact)
(#164 @hannesm)
### 0.8.3 (2022-11-11)
- Fix "DNS issues", a firewall ruleset with a domain name lead to 100% CPU usage
(reported by fiftyfourthparallel on
https://forum.qubes-os.org/t/mirage-firewall-0-8-2-broken-new-users-should-install-0-8-1/14566,
re-reported by @palainp in #158, fixed by @hannesm in mirage/mirage-nat#48
(release 3.0.1)) - underlying issue was a wrong definition of `is_port_free`
(since 3.0.0, used since mirage-qubes-firewall 0.8.2).
- Fix "crash on downstream vm start", after more than 64 client VMs have been
connected and disconnected with the qubes-mirage-firewall (reported by @xaki23
in #155, fixed by @hannesm in #161) - underlying issue was a leak of xenstore
watchers and a hard limit in xen on the amount of watchers
- Fix "detach netvm fails" (reported by @rootnoob in #157, fixed by @palainp
in mirage/mirage-net-xen#105 (release 2.1.2)) - underlying issue was that the
network interface state was never set to closed, but directly removed
- Fix potential DoS in handling DNS replies (#162 @hannesm)
- Avoid potential forever loop in My_nat.free_udp_port (#159 @hannesm)
- Assorted code removals (#161 @hannesm)
- Update to dns 6.4.0 changes (#154, @hannesm)
### 0.8.2 (2022-10-12)
- Advise to use 32 MB memory, which is sufficient (#150, @palainp)
- Improve documentation (#150, @palainp)
- Remove unneeded memory management code and log messages (#150, @palainp)
- Use mirage-nat 3.0.0, remove global mutable state (#151, @hannesm)
### 0.8.1 (2022-09-14)
- support qrexec protocol version 3 (@reynir @palainp in mirage-qubes 0.9.3)

View File

@ -1,35 +1,20 @@
# Pin the base image to a specific hash for maximum reproducibility.
# It will probably still work on newer images, though, unless an update
# changes some compiler optimisations (unlikely).
# bookworm-slim taken from https://hub.docker.com/_/debian/tags?page=1&name=bookworm-slim
FROM debian@sha256:3d5df92588469a4c503adbead0e4129ef3f88e223954011c2169073897547cac
# install remove default packages repository
RUN rm /etc/apt/sources.list.d/debian.sources
# and set the package source to a specific release too
# taken from https://snapshot.debian.org/archive/debian
RUN printf "deb [check-valid-until=no] http://snapshot.debian.org/archive/debian/20240419T024211Z bookworm main\n" > /etc/apt/sources.list
# taken from https://snapshot.debian.org/archive/debian-security/
RUN printf "deb [check-valid-until=no] http://snapshot.debian.org/archive/debian-security/20240419T111010Z bookworm-security main\n" >> /etc/apt/sources.list
# fedora-35-ocaml-4.14
FROM ocaml/opam@sha256:68b7ce1fd4c992d6f3bfc9b4b0a88ee572ced52427f0547b6e4eb6194415f585
ENV PATH="${PATH}:/home/opam/.opam/4.14/bin"
RUN apt update && apt install --no-install-recommends --no-install-suggests -y wget ca-certificates git patch unzip bzip2 make gcc g++ libc-dev
RUN wget -O /usr/bin/opam https://github.com/ocaml/opam/releases/download/2.3.0/opam-2.3.0-i686-linux && chmod 755 /usr/bin/opam
# taken from https://raw.githubusercontent.com/ocaml/opam/master/shell/install.sh
RUN test `sha512sum /usr/bin/opam | cut -d' ' -f1` = \
"4c0e8771889a36bad4d5f964e2e662d5b611e6f112777d3d4eea3eea919d109cd17826beba38e6cfa1ad9553a0a989d9268f911ea5485968da04b1e08efc7de2" || exit
# Since mirage 4.2 we must use opam version 2.1 or later
RUN sudo ln -sf /usr/bin/opam-2.1 /usr/bin/opam
ENV OPAMROOT=/tmp
ENV OPAMCONFIRMLEVEL=unsafe-yes
# Pin last known-good version for reproducible builds.
# Remove this line (and the base image pin above) if you want to test with the
# latest versions.
# taken from https://github.com/ocaml/opam-repository
RUN opam init --disable-sandboxing -a --bare https://github.com/ocaml/opam-repository.git#8f63148a9025a7b775a069a6c0b0385c22ad51d3
RUN opam switch create myswitch 4.14.2
RUN opam exec -- opam install -y mirage opam-monorepo ocaml-solo5
RUN mkdir /tmp/orb-build
ADD config.ml /tmp/orb-build/config.ml
WORKDIR /tmp/orb-build
CMD opam exec -- sh -exc 'mirage configure -t xen --extra-repos=\
opam-overlays:https://github.com/dune-universe/opam-overlays.git#f2bec38beca4aea9e481f2fd3ee319c519124649,\
mirage-overlays:https://github.com/dune-universe/mirage-opam-overlays.git#797cb363df3ff763c43c8fbec5cd44de2878757e \
&& make depend && make unikernel'
RUN cd /home/opam/opam-repository && git fetch origin master && git reset --hard 632ef7fd6add02a7789f896751c51b408dca0373 && opam update
RUN opam install -y mirage opam-monorepo
RUN mkdir /home/opam/qubes-mirage-firewall
ADD config.ml /home/opam/qubes-mirage-firewall/config.ml
WORKDIR /home/opam/qubes-mirage-firewall
CMD opam exec -- mirage configure -t xen && make depend && make tar

View File

@ -1,23 +0,0 @@
Copyright (X) 2015-2024, the Qubes Mirage Firewall authors
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this
list of conditions and the following disclaimer in the documentation and/or
other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

View File

@ -1,5 +1,5 @@
MIRAGE_KERNEL_NAME = dist/qubes-firewall.xen
OCAML_VERSION ?= 4.14.2
OCAML_VERSION ?= 4.14.0
SOURCE_BUILD_DEP := firewall-build-dep
firewall-build-dep:

View File

@ -1,8 +1,10 @@
unikernel: build
cp dist/qubes-firewall.xen dist/qubes-firewall.xen.debug
strip dist/qubes-firewall.xen
cp dist/qubes-firewall.xen .
sha256sum qubes-firewall.xen
tar: build
rm -rf _build/mirage-firewall
mkdir _build/mirage-firewall
cp dist/qubes-firewall.xen _build/mirage-firewall/vmlinuz
touch _build/mirage-firewall/modules.img
cat /dev/null | gzip -n > _build/mirage-firewall/initramfs
tar cjf mirage-firewall.tar.bz2 -C _build --mtime=./build-with-docker.sh mirage-firewall
fetchmotron: qubes_firewall.xen
test-mirage qubes_firewall.xen mirage-fw-test &

View File

@ -13,60 +13,56 @@ See the [Deploy](#deploy) section below for installation instructions.
## Build from source
Note: The most reliable way to build is using Docker or Podman.
Fedora 38 works well for this, Debian 12 also works, but you'll need to follow the instructions at [docker.com][debian-docker] to get Docker
Note: The most reliable way to build is using Docker.
Fedora 35 works well for this and Debian 11 also works, but you'll need to follow the instructions at [docker.com][debian-docker] to get Docker
(don't use Debian's version).
Create a new Fedora-38 AppVM (or reuse an existing one). In the Qube's Settings (Basic / Disk storage), increase the private storage max size from the default 2048 MiB to 8192 MiB. Open a terminal.
Create a new Fedora-35 AppVM (or reuse an existing one). In the Qube's Settings (Basic / Disk storage), increase the private storage max size from the default 2048 MiB to 4096 MiB. Open a terminal.
Clone this Git repository and run the `build-with.sh` script with either `docker` or `podman` as argument (Note: The `chcon` call is mandatory on Fedora with new SELinux policies which do not allow to standardly keep the docker images in homedir):
Clone this Git repository and run the `build-with-docker.sh` script:
mkdir /home/user/docker
sudo ln -s /home/user/docker /var/lib/docker
sudo chcon -Rt container_file_t /home/user/docker
sudo dnf install docker
sudo systemctl start docker
git clone https://github.com/mirage/qubes-mirage-firewall.git
cd qubes-mirage-firewall
sudo ./build-with.sh docker
sudo ./build-with-docker.sh
Or
sudo systemctl start podman
git clone https://github.com/mirage/qubes-mirage-firewall.git
cd qubes-mirage-firewall
./build-with.sh podman
This took about 15 minutes on my laptop (it will be much quicker if you run it again).
The symlink step at the start isn't needed if your build VM is standalone. It gives Docker more disk space and avoids losing the Docker image cache when you reboot the Qube.
It's not needed with Podman as the containers lives in your home directory by default.
This took about 10 minutes on my laptop (it will be much quicker if you run it again).
The symlink step at the start isn't needed if your build VM is standalone.
It gives Docker more disk space and avoids losing the Docker image cache when you reboot the Qube.
Note: the object files are stored in the `_build` directory to speed up incremental builds.
If you change the dependencies, you will need to delete this directory before rebuilding.
It's OK to install the Docker or Podman package in a template VM if you want it to remain
It's OK to install the Docker package in a template VM if you want it to remain
after a reboot, but the build of the firewall itself should be done in a regular AppVM.
You can also build without that script, as for any normal Mirage unikernel;
see [the Mirage installation instructions](https://mirageos.org/wiki/install) for details.
You can also build without Docker, as for any normal Mirage unikernel;
see [the Mirage installation instructions](https://mirage.io/wiki/install) for details.
The build script fixes the versions of the libraries it uses, ensuring that you will get
exactly the same binary that is in the release. If you build without it, it will build
The Docker build fixes the versions of the libraries it uses, ensuring that you will get
exactly the same binary that is in the release. If you build without Docker, it will build
against the latest versions instead (and the hash will therefore probably not match).
However, it should still work fine.
## Deploy
### Manual deployment
If you want to deploy manually, you just need to download `qubes-firewall.xen` and
`qubes-firewall.sha256` in domU and check that the `.xen` file has a corresponding
hashsum. `qubes-firewall.xen` is the unikernel itself and should be copied to
`vmlinuz` in the `/var/lib/qubes/vm-kernels/mirage-firewall` directory in dom0, e.g.
(if `dev` is the AppVM where you built it):
If you want to deploy manually, unpack `mirage-firewall.tar.bz2` in domU. The tarball contains `vmlinuz`,
which is the unikernel itself, plus a dummy initramfs file that Qubes requires:
[user@dev ~]$ tar xjf mirage-firewall.tar.bz2
Copy `vmlinuz` to `/var/lib/qubes/vm-kernels/mirage-firewall` directory in dom0, e.g. (if `dev` is the AppVM where you built it):
[tal@dom0 ~]$ mkdir -p /var/lib/qubes/vm-kernels/mirage-firewall/
[tal@dom0 ~]$ cd /var/lib/qubes/vm-kernels/mirage-firewall/
[tal@dom0 mirage-firewall]$ qvm-run -p dev 'cat mirage-firewall/qubes-firewall.xen' > vmlinuz
[tal@dom0 mirage-firewall]$ qvm-run -p dev 'cat mirage-firewall/vmlinuz' > vmlinuz
Finally, create [a dummy file required by Qubes OS](https://github.com/QubesOS/qubes-issues/issues/5516):
[tal@dom0 mirage-firewall]$ gzip -n9 < /dev/null > initramfs
Run this command in dom0 to create a `mirage-firewall` VM using the `mirage-firewall` kernel you added above
@ -74,8 +70,8 @@ Run this command in dom0 to create a `mirage-firewall` VM using the `mirage-fire
qvm-create \
--property kernel=mirage-firewall \
--property kernelopts='' \
--property memory=32 \
--property maxmem=32 \
--property memory=64 \
--property maxmem=64 \
--property netvm=sys-net \
--property provides_network=True \
--property vcpus=1 \
@ -88,9 +84,6 @@ qvm-features mirage-firewall qubes-firewall 1
qvm-features mirage-firewall no-default-kernelopts 1
```
### Deployment using saltstack
If you're familiar how to run salt states in Qubes, you can also use the script `SaltScriptToDownloadAndInstallMirageFirewallInQubes.sls` to automatically deploy the latest version of mirage firewall in your Qubes OS. An introduction can be found [here](https://forum.qubes-os.org/t/qubes-salt-beginners-guide/20126) and [here](https://www.qubes-os.org/doc/salt/). Following the instructions from the former link, you can run the script in dom0 with the command `sudo qubesctl --show-output state.apply SaltScriptToDownloadAndInstallMirageFirewallInQubes saltenv=user`. The script checks the checksum from the integration server and compares with the latest version provided in the github releases. It might be necessary to adjust the VM templates in the script which are used for downloading of the mirage unikernel, if your default templates do not have the tools `curl` and `tar` installed by default. Also don't forget to change the VMs in which the uni kernel should be used or adjust the "Qubes Global Settings".
## Upgrading
To upgrade from an earlier release, just overwrite `/var/lib/qubes/vm-kernels/mirage-firewall/vmlinuz` with the new version and restart the firewall VM.
@ -116,17 +109,6 @@ https://www.qubes-os.org/doc/software-update-dom0/ says:
> there are no significant security implications in this choice. By default,
> this role is assigned to the firewallvm.
### Configure firewall with OpenBSD-like netvm
OpenBSD is currently unable to be used as netvm, so if you want to use a BSD as your sys-net VM, you'll need to set its netvm to qubes-mirage-firewall (see https://github.com/mirage/qubes-mirage-firewall/issues/146 for more information).
That means you'll have `AppVMs -> qubes-mirage-firewall <- OpenBSD` with the arrow standing for the netvm property setting.
In that case you'll have to tell qubes-mirage-firewall which AppVM client should be used as uplink:
```
qvm-prefs --set mirage-firewall -- kernelopts '--ipv4=X.X.X.X --ipv4-gw=Y.Y.Y.Y'
```
with `X.X.X.X` the IP address for mirage-firewall and `Y.Y.Y.Y` the IP address of your OpenBSD HVM.
### Components
This diagram show the main components (each box corresponds to a source `.ml` file with the same name):
@ -155,7 +137,7 @@ The boot process:
For development, use the [test-mirage][] scripts to deploy the unikernel (`qubes-firewall.xen`) from your development AppVM.
This takes a little more setting up the first time, but will be much quicker after that. e.g.
[user@dev ~]$ test-mirage dist/qubes-firewall.xen mirage-firewall
$ test-mirage qubes_firewall.xen mirage-firewall
Waiting for 'Ready'... OK
Uploading 'dist/qubes-firewall.xen' (7454880 bytes) to "mirage-test"
Waiting for 'Booting'... OK
@ -166,25 +148,25 @@ This takes a little more setting up the first time, but will be much quicker aft
\__ \ ( | | ( | ) |
____/\___/ _|\___/____/
Solo5: Bindings version v0.7.3
Solo5: Memory map: 32 MB addressable:
Solo5: Memory map: 64 MB addressable:
Solo5: reserved @ (0x0 - 0xfffff)
Solo5: text @ (0x100000 - 0x319fff)
Solo5: rodata @ (0x31a000 - 0x384fff)
Solo5: data @ (0x385000 - 0x53ffff)
Solo5: heap >= 0x540000 < stack < 0x2000000
Solo5: text @ (0x100000 - 0x31bfff)
Solo5: rodata @ (0x31c000 - 0x386fff)
Solo5: data @ (0x387000 - 0x544fff)
Solo5: heap >= 0x545000 < stack < 0x4000000
2022-08-13 14:55:38 -00:00: INF [qubes.rexec] waiting for client...
2022-08-13 14:55:38 -00:00: INF [qubes.gui] waiting for client...
2022-08-13 14:55:38 -00:00: INF [qubes.db] connecting to server...
2022-08-13 14:55:38 -00:00: INF [qubes.db] connected
2022-08-13 14:55:38 -00:00: INF [qubes.db] got update: "/mapped-ip/10.137.0.20/visible-ip" = "10.137.0.20"
2022-08-13 14:55:38 -00:00: INF [qubes.db] got update: "/mapped-ip/10.137.0.20/visible-gateway" = "10.137.0.23"
2022-08-13 14:55:38 -00:00: INF [qubes.rexec] client connected, using protocol version 3
2022-08-13 14:55:38 -00:00: INF [qubes.rexec] client connected, other end wants to use protocol version 3, continuing with version 2
2022-08-13 14:55:38 -00:00: INF [unikernel] QubesDB and qrexec agents connected in 0.041 s
2022-08-13 14:55:38 -00:00: INF [dao] Got network configuration from QubesDB:
NetVM IP on uplink network: 10.137.0.4
Our IP on uplink network: 10.137.0.23
Our IP on client networks: 10.137.0.23
DNS resolver: 10.139.1.1
DNS secondary resolver: 10.139.1.2
2022-08-13 14:55:38 -00:00: INF [net-xen frontend] connect 0
2022-08-13 14:55:38 -00:00: INF [net-xen frontend] create: id=0 domid=1
2022-08-13 14:55:38 -00:00: INF [net-xen frontend] sg:true gso_tcpv4:true rx_copy:true rx_flip:false smart_poll:false
@ -194,7 +176,7 @@ This takes a little more setting up the first time, but will be much quicker aft
2022-08-13 14:55:38 -00:00: INF [ARP] Sending gratuitous ARP for 10.137.0.23 (00:16:3e:5e:6c:00)
2022-08-13 14:55:38 -00:00: INF [udp] UDP layer connected on 10.137.0.23
2022-08-13 14:55:38 -00:00: INF [dao] Watching backend/vif
2022-08-13 14:55:38 -00:00: INF [memory_pressure] Writing meminfo: free 20MiB / 27MiB (72.68 %)
2022-08-13 14:55:38 -00:00: INF [memory_pressure] Writing meminfo: free 52MiB / 59MiB (87.55 %)
# Testing if the firewall works
@ -207,7 +189,16 @@ See [issues tagged "security"](https://github.com/mirage/qubes-mirage-firewall/i
# LICENSE
See [LICENSE.md](https://github.com/mirage/qubes-mirage-firewall/blob/main/LICENSE.md)
Copyright (c) 2019, Thomas Leonard
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
[test-mirage]: https://github.com/talex5/qubes-test-mirage
[mirage-qubes]: https://github.com/mirage/mirage-qubes

View File

@ -1,104 +0,0 @@
# How to install the superlight mirage-firewall for Qubes OS by using saltstack
# Tested on Qubes v4.1 and mirage v0.8.5
# After the install, you have to switch your AppVMs to use the mirage firewall vm created by this script e.g. by using "Qubes Global Settings"
# inspired by: https://github.com/one7two99/my-qubes/tree/master/mirage-firewall
# default template + dispvm template are used. Possible optimization is to use min-dvms
{% set DownloadVMTemplate = salt['cmd.shell']("qubes-prefs default_template") %}
{% set DispVM = salt['cmd.shell']("qubes-prefs default_dispvm") %}
{% set DownloadVM = "DownloadVmMirage" %}
{% set MirageFW = "sys-mirage-fw" %}
{% set GithubUrl = "https://github.com/mirage/qubes-mirage-firewall" %}
{% set Kernel = "qubes-firewall.xen" %}
{% set Shasum = "qubes-firewall-release.sha256" %}
{% set MirageInstallDir = "/var/lib/qubes/vm-kernels/mirage-firewall" %}
#download and install the latest version
{% set Release = salt['cmd.shell']("qvm-run --dispvm " ~ DispVM ~ " --pass-io \"curl --silent --location -o /dev/null -w %{url_effective} " ~ GithubUrl ~ "/releases/latest | rev | cut -d \"/\" -f 1 | rev\"") %}
{% if Release != salt['cmd.shell']("test -e " ~ MirageInstallDir ~ "/version.txt" ~ " || mkdir " ~ MirageInstallDir ~ " ; touch " ~ MirageInstallDir ~ "/version.txt" ~ " ; cat " ~ MirageInstallDir ~ "/version.txt") %}
create-downloader-VM:
qvm.vm:
- name: {{ DownloadVM }}
- present:
- template: {{ DownloadVMTemplate }}
- label: red
- prefs:
- template: {{ DownloadVMTemplate }}
- include-in-backups: false
{% set DownloadBinary = GithubUrl ~ "/releases/download/" ~ Release ~ "/" ~ Kernel %}
{% set DownloadShasum = GithubUrl ~ "/releases/download/" ~ Release ~ "/" ~ Shasum %}
download-and-unpack-in-DownloadVM4mirage:
cmd.run:
- names:
- qvm-run --pass-io {{ DownloadVM }} {{ "curl -L -O " ~ DownloadBinary }}
- qvm-run --pass-io {{ DownloadVM }} {{ "curl -L -O " ~ DownloadShasum }}
- require:
- create-downloader-VM
check-checksum-in-DownloadVM:
cmd.run:
- names:
- qvm-run --pass-io {{ DownloadVM }} {{ "\"echo \\\"Checksum of release on github:\\\";cat " ~ Shasum ~ " | cut -d\' \' -f1\"" }}
- qvm-run --pass-io {{ DownloadVM }} {{ "\"echo \\\"Checksum of downloaded local file:\\\";sha256sum " ~ Kernel ~ " | cut -d\' \' -f1\"" }}
- qvm-run --pass-io {{ DownloadVM }} {{ "\"diff <(cat " ~ Shasum ~ " | cut -d\' \' -f1) <(sha256sum " ~ Kernel ~ " | cut -d\' \' -f1) && echo \\\"Checksums DO match.\\\" || (echo \\\"Checksums do NOT match.\\\";exit 101)\"" }}
- require:
- download-and-unpack-in-DownloadVM4mirage
copy-mirage-kernel-to-dom0:
cmd.run:
- name: mkdir -p {{ MirageInstallDir }}; qvm-run --pass-io --no-gui {{ DownloadVM }} {{ "cat " ~ Kernel }} > {{ MirageInstallDir ~ "/vmlinuz" }}
- require:
- download-and-unpack-in-DownloadVM4mirage
- check-checksum-in-DownloadVM
update-version:
cmd.run:
- names:
- echo {{ Release }} > {{ MirageInstallDir ~ "/version.txt" }}
- require:
- copy-mirage-kernel-to-dom0
create-sys-mirage-fw:
qvm.vm:
- name: {{ MirageFW }}
- present:
- class: StandaloneVM
- label: black
- prefs:
- kernel: mirage-firewall
- kernelopts:
- include-in-backups: False
- memory: 32
- maxmem: 32
- netvm: sys-net
- provides-network: True
- vcpus: 1
- virt-mode: pvh
- features:
- enable:
- qubes-firewall
- no-default-kernelopts
- require:
- copy-mirage-kernel-to-dom0
cleanup-in-DownloadVM:
cmd.run:
- names:
- qvm-run -a --pass-io --no-gui {{ DownloadVM }} "{{ "rm " ~ Kernel ~ " " ~ Shasum }}"
- require:
- update-version
remove-DownloadVM4mirage:
qvm.absent:
- name: {{ DownloadVM }}
- require:
- cleanup-in-DownloadVM
{% endif %}

9
build-with-docker.sh Executable file
View File

@ -0,0 +1,9 @@
#!/bin/sh
set -eu
echo Building Docker image with dependencies..
docker build -t qubes-mirage-firewall .
echo Building Firewall...
docker run --rm -i -v `pwd`:/home/opam/qubes-mirage-firewall qubes-mirage-firewall
echo "SHA2 of build: $(sha256sum ./dist/qubes-firewall.xen)"
echo "SHA2 last known: d0ec19d5b392509955edccf100852bcc9c0e05bf31f1ec25c9cc9c9e74c3b7bf"
echo "(hashes should match for released versions)"

View File

@ -1,25 +0,0 @@
#!/bin/sh
set -eu
if [[ $# -ne 1 ]] ; then
echo "Usage: build-with.sh { docker | podman }"
exit 1
fi
builder=$1
case $builder in
docker|podman)
;;
*)
echo "You should use either docker or podman for building"
exit 2
esac
echo Building $builder image with dependencies..
$builder build -t qubes-mirage-firewall .
echo Building Firewall...
$builder run --rm -i -v `pwd`:/tmp/orb-build:Z qubes-mirage-firewall
echo "SHA2 of build: $(sha256sum ./dist/qubes-firewall.xen | cut -d' ' -f1)"
echo "SHA2 current head: $(cat qubes-firewall.sha256 | cut -d' ' -f1)"
echo "SHA2 last release: $(cat qubes-firewall-release.sha256 | cut -d' ' -f1)"
echo "(hashes should match for head versions)"

View File

@ -4,7 +4,9 @@
type t = (unit -> unit) list ref
let create () = ref []
let on_cleanup t fn = t := fn :: !t
let on_cleanup t fn =
t := fn :: !t
let cleanup t =
let tasks = !t in

View File

@ -1,8 +1,8 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** Register actions to take when a resource is finished. Like [Lwt_switch], but
synchronous. *)
(** Register actions to take when a resource is finished.
Like [Lwt_switch], but synchronous. *)
type t

View File

@ -4,117 +4,109 @@
open Fw_utils
open Lwt.Infix
let src =
Logs.Src.create "client_eth" ~doc:"Ethernet networks for NetVM clients"
let src = Logs.Src.create "client_eth" ~doc:"Ethernet networks for NetVM clients"
module Log = (val Logs.src_log src : Logs.LOG)
type t = {
mutable iface_of_ip : client_link Ipaddr.V4.Map.t;
changed : unit Lwt_condition.t; (* Fires when [iface_of_ip] changes. *)
my_ip : Ipaddr.V4.t;
(* The IP that clients are given as their default gateway. *)
mutable iface_of_ip : client_link IpMap.t;
changed : unit Lwt_condition.t; (* Fires when [iface_of_ip] changes. *)
client_gw : Ipaddr.V4.t; (* The IP that clients are given as their default gateway. *)
}
type host = [ `Client of client_link | `Firewall | `External of Ipaddr.t ]
type host =
[ `Client of client_link
| `Firewall
| `External of Ipaddr.t ]
let create config =
let create ~client_gw =
let changed = Lwt_condition.create () in
let my_ip = config.Dao.our_ip in
Lwt.return { iface_of_ip = Ipaddr.V4.Map.empty; my_ip; changed }
{ iface_of_ip = IpMap.empty; client_gw; changed }
let client_gw t = t.my_ip
let client_gw t = t.client_gw
let add_client t iface =
let ip = iface#other_ip in
let rec aux () =
match Ipaddr.V4.Map.find_opt ip t.iface_of_ip with
match IpMap.find ip t.iface_of_ip with
| Some old ->
(* Wait for old client to disappear before adding one with the same IP address.
(* Wait for old client to disappear before adding one with the same IP address.
Otherwise, its [remove_client] call will remove the new client instead. *)
Log.info (fun f ->
f ~header:iface#log_header
"Waiting for old client %s to go away before accepting new one"
old#log_header);
Lwt_condition.wait t.changed >>= aux
Log.info (fun f -> f ~header:iface#log_header "Waiting for old client %s to go away before accepting new one" old#log_header);
Lwt_condition.wait t.changed >>= aux
| None ->
t.iface_of_ip <- t.iface_of_ip |> Ipaddr.V4.Map.add ip iface;
Lwt_condition.broadcast t.changed ();
Lwt.return_unit
t.iface_of_ip <- t.iface_of_ip |> IpMap.add ip iface;
Lwt_condition.broadcast t.changed ();
Lwt.return_unit
in
aux ()
let remove_client t iface =
let ip = iface#other_ip in
assert (Ipaddr.V4.Map.mem ip t.iface_of_ip);
t.iface_of_ip <- t.iface_of_ip |> Ipaddr.V4.Map.remove ip;
assert (IpMap.mem ip t.iface_of_ip);
t.iface_of_ip <- t.iface_of_ip |> IpMap.remove ip;
Lwt_condition.broadcast t.changed ()
let lookup t ip = Ipaddr.V4.Map.find_opt ip t.iface_of_ip
let lookup t ip = IpMap.find ip t.iface_of_ip
let classify t ip =
match ip with
| Ipaddr.V6 _ -> `External ip
| Ipaddr.V4 ip4 -> (
if ip4 = t.my_ip then `Firewall
else
match lookup t ip4 with
| Some client_link -> `Client client_link
| None -> `External ip)
| Ipaddr.V4 ip4 ->
if ip4 = t.client_gw then `Firewall
else match lookup t ip4 with
| Some client_link -> `Client client_link
| None -> `External ip
let resolve t : host -> Ipaddr.t = function
| `Client client_link -> Ipaddr.V4 client_link#other_ip
| `Firewall -> Ipaddr.V4 t.my_ip
| `Firewall -> Ipaddr.V4 t.client_gw
| `External addr -> addr
module ARP = struct
type arp = { net : t; client_link : client_link }
type arp = {
net : t;
client_link : client_link;
}
let lookup t ip =
if ip = t.net.my_ip then Some t.client_link#my_mac
if ip = t.net.client_gw then Some t.client_link#my_mac
else if (Ipaddr.V4.to_octets ip).[3] = '\x01' then (
Log.info (fun f ->
f ~header:t.client_link#log_header
"Request for %a is invalid, but pretending it's me (see Qubes \
issue #5022)"
Ipaddr.V4.pp ip);
Some t.client_link#my_mac)
else None
Log.info (fun f -> f ~header:t.client_link#log_header
"Request for %a is invalid, but pretending it's me (see Qubes issue #5022)" Ipaddr.V4.pp ip);
Some t.client_link#my_mac
) else None
(* We're now treating client networks as point-to-point links,
so we no longer respond on behalf of other clients. *)
(*
else match Ipaddr.V4.Map.find_opt ip t.net.iface_of_ip with
(*
else match IpMap.find ip t.net.iface_of_ip with
| Some client_iface -> Some client_iface#other_mac
| None -> None
*)
let create ~net client_link = { net; client_link }
let create ~net client_link = {net; client_link}
let input_query t arp =
let req_ipv4 = arp.Arp_packet.target_ip in
let pf (f : ?header:string -> ?tags:_ -> _) fmt =
f ~header:t.client_link#log_header ("who-has %a? " ^^ fmt) Ipaddr.V4.pp
req_ipv4
f ~header:t.client_link#log_header ("who-has %a? " ^^ fmt) Ipaddr.V4.pp req_ipv4
in
if req_ipv4 = t.client_link#other_ip then (
Log.info (fun f -> pf f "ignoring request for client's own IP");
None)
else
match lookup t req_ipv4 with
None
) else match lookup t req_ipv4 with
| None ->
Log.info (fun f -> pf f "unknown address; not responding");
None
Log.info (fun f -> pf f "unknown address; not responding");
None
| Some req_mac ->
Log.info (fun f -> pf f "responding with %a" Macaddr.pp req_mac);
Some
{
Arp_packet.operation = Arp_packet.Reply;
(* The Target Hardware Address and IP are copied from the request *)
target_ip = arp.Arp_packet.source_ip;
target_mac = arp.Arp_packet.source_mac;
source_ip = req_ipv4;
source_mac = req_mac;
}
Log.info (fun f -> pf f "responding with %a" Macaddr.pp req_mac);
Some { Arp_packet.
operation = Arp_packet.Reply;
(* The Target Hardware Address and IP are copied from the request *)
target_ip = arp.Arp_packet.source_ip;
target_mac = arp.Arp_packet.source_mac;
source_ip = req_ipv4;
source_mac = req_mac;
}
let input_gratuitous t arp =
let source_ip = arp.Arp_packet.source_ip in
@ -122,28 +114,18 @@ module ARP = struct
let header = t.client_link#log_header in
match lookup t source_ip with
| Some real_mac when Macaddr.compare source_mac real_mac = 0 ->
Log.info (fun f ->
f ~header "client suggests updating %s -> %s (as expected)"
(Ipaddr.V4.to_string source_ip)
(Macaddr.to_string source_mac))
Log.info (fun f -> f ~header "client suggests updating %s -> %s (as expected)"
(Ipaddr.V4.to_string source_ip) (Macaddr.to_string source_mac));
| Some other_mac ->
Log.warn (fun f ->
f ~header "client suggests incorrect update %s -> %s (should be %s)"
(Ipaddr.V4.to_string source_ip)
(Macaddr.to_string source_mac)
(Macaddr.to_string other_mac))
Log.warn (fun f -> f ~header "client suggests incorrect update %s -> %s (should be %s)"
(Ipaddr.V4.to_string source_ip) (Macaddr.to_string source_mac) (Macaddr.to_string other_mac));
| None ->
Log.warn (fun f ->
f ~header
"client suggests incorrect update %s -> %s (unexpected IP)"
(Ipaddr.V4.to_string source_ip)
(Macaddr.to_string source_mac))
Log.warn (fun f -> f ~header "client suggests incorrect update %s -> %s (unexpected IP)"
(Ipaddr.V4.to_string source_ip) (Macaddr.to_string source_mac))
let input t arp =
let op = arp.Arp_packet.operation in
match op with
| Arp_packet.Request -> input_query t arp
| Arp_packet.Reply ->
input_gratuitous t arp;
None
| Arp_packet.Reply -> input_gratuitous t arp; None
end

View File

@ -1,32 +1,34 @@
(* Copyright (C) 2016, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** The ethernet networks connecting us to our client AppVMs. Note: each AppVM
is on a point-to-point link, each link being considered to be a separate
Ethernet network. *)
(** The ethernet networks connecting us to our client AppVMs.
Note: each AppVM is on a point-to-point link, each link being considered to be a separate Ethernet network. *)
open Fw_utils
type t
(** A collection of clients. *)
type host = [ `Client of client_link | `Firewall | `External of Ipaddr.t ]
type host =
[ `Client of client_link
| `Firewall
| `External of Ipaddr.t ]
(* Note: Qubes does not allow us to distinguish between an external address and a
disconnected client.
See: https://github.com/talex5/qubes-mirage-firewall/issues/9#issuecomment-246956850 *)
val create : Dao.network_config -> t Lwt.t
(** [create ~client_gw] is a network of client machines. Qubes will have
configured the client machines to use [client_gw] as their default gateway.
*)
val create : client_gw:Ipaddr.V4.t -> t
(** [create ~client_gw] is a network of client machines.
Qubes will have configured the client machines to use [client_gw] as their default gateway. *)
val add_client : t -> client_link -> unit Lwt.t
(** [add_client t client] registers a new client. If a client with this IP
address is already registered, it waits for [remove_client] to be called on
that before adding the new client and returning. *)
(** [add_client t client] registers a new client. If a client with this IP address is already registered,
it waits for [remove_client] to be called on that before adding the new client and returning. *)
val remove_client : t -> client_link -> unit
val client_gw : t -> Ipaddr.V4.t
val classify : t -> Ipaddr.t -> host
val resolve : t -> host -> Ipaddr.t
@ -34,18 +36,18 @@ val lookup : t -> Ipaddr.V4.t -> client_link option
(** [lookup t addr] is the client with IP address [addr], if connected. *)
module ARP : sig
(** We already know the correct mapping of IP addresses to MAC addresses, so
we never allow clients to update it. We log a warning if a client attempts
to set incorrect information. *)
(** We already know the correct mapping of IP addresses to MAC addresses, so we never
allow clients to update it. We log a warning if a client attempts to set incorrect
information. *)
type arp
(** An ARP-responder for one client. *)
val create : net:t -> client_link -> arp
(** [create ~net client_link] is an ARP responder for [client_link]. It
answers only for the client's gateway address. *)
(** [create ~net client_link] is an ARP responder for [client_link].
It answers only for the client's gateway address. *)
val input : arp -> Arp_packet.t -> Arp_packet.t option
(** Process one ethernet frame containing an ARP message. Returns a response
frame, if one is needed. *)
(** Process one ethernet frame containing an ARP message.
Returns a response frame, if one is needed. *)
end

170
client_net.ml Normal file
View File

@ -0,0 +1,170 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Lwt.Infix
open Fw_utils
module Netback = Netchannel.Backend.Make(Netchannel.Xenstore.Make(Xen_os.Xs))
module ClientEth = Ethernet.Make(Netback)
let src = Logs.Src.create "client_net" ~doc:"Client networking"
module Log = (val Logs.src_log src : Logs.LOG)
let writev eth dst proto fillfn =
Lwt.catch
(fun () ->
ClientEth.write eth dst proto fillfn >|= function
| Ok () -> ()
| Error e ->
Log.err (fun f -> f "error trying to send to client: @[%a@]"
ClientEth.pp_error e);
)
(fun ex ->
(* Usually Netback_shutdown, because the client disconnected *)
Log.err (fun f -> f "uncaught exception trying to send to client: @[%s@]"
(Printexc.to_string ex));
Lwt.return_unit
)
class client_iface eth ~domid ~gateway_ip ~client_ip client_mac : client_link =
let log_header = Fmt.str "dom%d:%a" domid Ipaddr.V4.pp client_ip in
object
val queue = FrameQ.create (Ipaddr.V4.to_string client_ip)
val mutable rules = []
method get_rules = rules
method set_rules new_db = rules <- Dao.read_rules new_db client_ip
method my_mac = ClientEth.mac eth
method other_mac = client_mac
method my_ip = gateway_ip
method other_ip = client_ip
method writev proto fillfn =
FrameQ.send queue (fun () ->
writev eth client_mac proto fillfn
)
method log_header = log_header
end
let clients : Cleanup.t Dao.VifMap.t ref = ref Dao.VifMap.empty
(** Handle an ARP message from the client. *)
let input_arp ~fixed_arp ~iface request =
match Arp_packet.decode request with
| Error e ->
Log.warn (fun f -> f "Ignored unknown ARP message: %a" Arp_packet.pp_error e);
Lwt.return_unit
| Ok arp ->
match Client_eth.ARP.input fixed_arp arp with
| None -> Lwt.return_unit
| Some response ->
iface#writev `ARP (fun b -> Arp_packet.encode_into response b; Arp_packet.size)
(** Handle an IPv4 packet from the client. *)
let input_ipv4 get_ts cache ~iface ~router dns_client dns_servers packet =
let cache', r = Nat_packet.of_ipv4_packet !cache ~now:(get_ts ()) packet in
cache := cache';
match r with
| Error e ->
Log.warn (fun f -> f "Ignored unknown IPv4 message: %a" Nat_packet.pp_error e);
Lwt.return_unit
| Ok None -> Lwt.return_unit
| Ok (Some packet) ->
let `IPv4 (ip, _) = packet in
let src = ip.Ipv4_packet.src in
if src = iface#other_ip then Firewall.ipv4_from_client dns_client dns_servers router ~src:iface packet
else (
Log.warn (fun f -> f "Incorrect source IP %a in IP packet from %a (dropping)"
Ipaddr.V4.pp src Ipaddr.V4.pp iface#other_ip);
Lwt.return_unit
)
(** Connect to a new client's interface and listen for incoming frames and firewall rule changes. *)
let add_vif get_ts { Dao.ClientVif.domid; device_id } dns_client dns_servers ~client_ip ~router ~cleanup_tasks qubesDB =
Netback.make ~domid ~device_id >>= fun backend ->
Log.info (fun f -> f "Client %d (IP: %s) ready" domid (Ipaddr.V4.to_string client_ip));
ClientEth.connect backend >>= fun eth ->
let client_mac = Netback.frontend_mac backend in
let client_eth = router.Router.client_eth in
let gateway_ip = Client_eth.client_gw client_eth in
let iface = new client_iface eth ~domid ~gateway_ip ~client_ip client_mac in
(* update the rules whenever QubesDB notices a change for this IP *)
let qubesdb_updater =
Lwt.catch
(fun () ->
let rec update current_db current_rules =
Qubes.DB.got_new_commit qubesDB (Dao.db_root client_ip) current_db >>= fun new_db ->
iface#set_rules new_db;
let new_rules = iface#get_rules in
(if current_rules = new_rules then
Log.debug (fun m -> m "Rules did not change for %s" (Ipaddr.V4.to_string client_ip))
else begin
Log.debug (fun m -> m "New firewall rules for %s@.%a"
(Ipaddr.V4.to_string client_ip)
Fmt.(list ~sep:(any "@.") Pf_qubes.Parse_qubes.pp_rule) new_rules);
(* empty NAT table if rules are updated: they might deny old connections *)
My_nat.remove_connections router.Router.nat router.Router.ports client_ip;
end);
update new_db new_rules
in
update Qubes.DB.KeyMap.empty [])
(function Lwt.Canceled -> Lwt.return_unit | e -> Lwt.fail e)
in
Cleanup.on_cleanup cleanup_tasks (fun () -> Lwt.cancel qubesdb_updater);
Router.add_client router iface >>= fun () ->
Cleanup.on_cleanup cleanup_tasks (fun () -> Router.remove_client router iface);
let fixed_arp = Client_eth.ARP.create ~net:client_eth iface in
let fragment_cache = ref (Fragments.Cache.empty (256 * 1024)) in
let listener =
Lwt.catch
(fun () ->
Netback.listen backend ~header_size:Ethernet.Packet.sizeof_ethernet (fun frame ->
match Ethernet.Packet.of_cstruct frame with
| Error err -> Log.warn (fun f -> f "Invalid Ethernet frame: %s" err); Lwt.return_unit
| Ok (eth, payload) ->
match eth.Ethernet.Packet.ethertype with
| `ARP -> input_arp ~fixed_arp ~iface payload
| `IPv4 -> input_ipv4 get_ts fragment_cache ~iface ~router dns_client dns_servers payload
| `IPv6 -> Lwt.return_unit (* TODO: oh no! *)
)
>|= or_raise "Listen on client interface" Netback.pp_error)
(function Lwt.Canceled -> Lwt.return_unit | e -> Lwt.fail e)
in
Cleanup.on_cleanup cleanup_tasks (fun () -> Lwt.cancel listener);
Lwt.pick [ qubesdb_updater ; listener ]
(** A new client VM has been found in XenStore. Find its interface and connect to it. *)
let add_client get_ts dns_client dns_servers ~router vif client_ip qubesDB =
let cleanup_tasks = Cleanup.create () in
Log.info (fun f -> f "add client vif %a with IP %a"
Dao.ClientVif.pp vif Ipaddr.V4.pp client_ip);
Lwt.async (fun () ->
Lwt.catch (fun () ->
add_vif get_ts vif dns_client dns_servers ~client_ip ~router ~cleanup_tasks qubesDB
)
(fun ex ->
Log.warn (fun f -> f "Error with client %a: %s"
Dao.ClientVif.pp vif (Printexc.to_string ex));
Lwt.return_unit
)
);
cleanup_tasks
(** Watch XenStore for notifications of new clients. *)
let listen get_ts dns_client dns_servers qubesDB router =
Dao.watch_clients (fun new_set ->
(* Check for removed clients *)
!clients |> Dao.VifMap.iter (fun key cleanup ->
if not (Dao.VifMap.mem key new_set) then (
clients := !clients |> Dao.VifMap.remove key;
Log.info (fun f -> f "client %a has gone" Dao.ClientVif.pp key);
Cleanup.cleanup cleanup
)
);
(* Check for added clients *)
new_set |> Dao.VifMap.iter (fun key ip_addr ->
if not (Dao.VifMap.mem key !clients) then (
let cleanup = add_client get_ts dns_client dns_servers ~router key ip_addr qubesDB in
Log.debug (fun f -> f "client %a arrived" Dao.ClientVif.pp key);
clients := !clients |> Dao.VifMap.add key cleanup
)
)
)

12
client_net.mli Normal file
View File

@ -0,0 +1,12 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** Handling client VMs. *)
val listen : (unit -> int64) ->
([ `host ] Domain_name.t -> (int32 * Ipaddr.V4.Set.t, [> `Msg of string ]) result Lwt.t) ->
Ipaddr.V4.t list -> Qubes.DB.t -> Router.t -> 'a Lwt.t
(** [listen get_timestamp resolver dns_servers db router] is a thread that watches for clients being added to and
removed from XenStore. Clients are connected to the client network and
packets are sent via [router]. We ensure the source IP address is correct
before routing a packet. *)

View File

@ -4,30 +4,24 @@
(** Commands we provide via qvm-run. *)
open Lwt
module Flow = Qubes.RExec.Flow
let src = Logs.Src.create "command" ~doc:"qrexec command handler"
module Log = (val Logs.src_log src : Logs.LOG)
let set_date_time flow =
Flow.read_line flow >|= function
| `Eof ->
Log.warn (fun f -> f "EOF reading time from dom0");
1
| `Ok line ->
Log.info (fun f -> f "TODO: set time to %S" line);
0
| `Eof -> Log.warn (fun f -> f "EOF reading time from dom0"); 1
| `Ok line -> Log.info (fun f -> f "TODO: set time to %S" line); 0
let handler ~user:_ cmd flow =
(* Write a message to the client and return an exit status of 1. *)
let error fmt =
fmt
|> Printf.ksprintf @@ fun s ->
Log.warn (fun f -> f "<< %s" s);
Flow.ewritef flow "%s [while processing %S]" s cmd >|= fun () -> 1
in
fmt |> Printf.ksprintf @@ fun s ->
Log.warn (fun f -> f "<< %s" s);
Flow.ewritef flow "%s [while processing %S]" s cmd >|= fun () -> 1 in
match cmd with
| "QUBESRPC qubes.SetDateTime dom0" -> set_date_time flow
| "QUBESRPC qubes.WaitForSession none" -> return 0 (* Always ready! *)
| "QUBESRPC qubes.WaitForSession none" -> return 0 (* Always ready! *)
| cmd -> error "Unknown command %S" cmd

View File

@ -1,4 +1,3 @@
(* mirage >= 4.9.0 & < 4.10.0 *)
(* Copyright (C) 2017, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
@ -6,25 +5,36 @@
open Mirage
let main =
main
~packages:
[
package "vchan" ~min:"4.0.2";
package "cstruct";
package "tcpip" ~min:"3.7.0";
package ~min:"2.3.0" ~sublibs:[ "mirage" ] "arp";
package ~min:"3.0.0" "ethernet";
package "shared-memory-ring" ~min:"3.0.0";
package "mirage-net-xen" ~min:"2.1.4";
package "ipaddr" ~min:"5.2.0";
package "mirage-qubes" ~min:"0.9.1";
package ~min:"3.0.1" "mirage-nat";
package "mirage-logs";
package "mirage-xen" ~min:"8.0.0";
package ~min:"6.4.0" "dns-client";
package "pf-qubes";
]
"Unikernel" job
let table_size =
let info = Key.Arg.info
~doc:"The number of NAT entries to allocate."
~docv:"ENTRIES" ["nat-table-size"]
in
let key = Key.Arg.opt ~stage:`Both Key.Arg.int 5_000 info in
Key.create "nat_table_size" key
let () = register "qubes-firewall" [ main ]
let main =
foreign
~keys:[Key.v table_size]
~packages:[
package "vchan" ~min:"4.0.2";
package "cstruct";
package "astring";
package "tcpip" ~min:"3.7.0";
package ~min:"2.3.0" ~sublibs:["mirage"] "arp";
package ~min:"3.0.0" "ethernet";
package "shared-memory-ring" ~min:"3.0.0";
package "netchannel" ~min:"1.11.0";
package "mirage-net-xen";
package "ipaddr" ~min:"5.2.0";
package "mirage-qubes" ~min:"0.9.1";
package "mirage-nat" ~min:"2.2.1";
package "mirage-logs";
package "mirage-xen" ~min:"8.0.0";
package ~min:"6.1.0" "dns-client";
package "pf-qubes";
]
"Unikernel.Main" (random @-> mclock @-> time @-> job)
let () =
register "qubes-firewall" [main $ default_random $ default_monotonic_clock $ default_time]

215
dao.ml
View File

@ -3,36 +3,38 @@
open Lwt.Infix
open Qubes
open Astring
let src = Logs.Src.create "dao" ~doc:"QubesDB data access"
module Log = (val Logs.src_log src : Logs.LOG)
module ClientVif = struct
type t = { domid : int; device_id : int }
type t = {
domid : int;
device_id : int;
}
let pp f { domid; device_id } =
Fmt.pf f "{domid=%d;device_id=%d}" domid device_id
let pp f { domid; device_id } = Fmt.pf f "{domid=%d;device_id=%d}" domid device_id
let compare = compare
end
module VifMap = struct
include Map.Make (ClientVif)
include Map.Make(ClientVif)
let rec of_list = function
| [] -> empty
| (k, v) :: rest -> add k v (of_list rest)
let find key t = try Some (find key t) with Not_found -> None
let find key t =
try Some (find key t)
with Not_found -> None
end
let directory ~handle dir =
Xen_os.Xs.directory handle dir >|= function
| [ "" ] -> [] (* XenStore client bug *)
| [""] -> [] (* XenStore client bug *)
| items -> items
let db_root client_ip = "/qubes-firewall/" ^ Ipaddr.V4.to_string client_ip
let db_root client_ip =
"/qubes-firewall/" ^ (Ipaddr.V4.to_string client_ip)
let read_rules rules client_ip =
let root = db_root client_ip in
@ -41,101 +43,88 @@ let read_rules rules client_ip =
Log.debug (fun f -> f "reading %s" pattern);
match Qubes.DB.KeyMap.find_opt pattern rules with
| None ->
Log.debug (fun f -> f "rule %d does not exist; won't look for more" n);
Ok (List.rev l)
| Some rule -> (
Log.debug (fun f -> f "rule %d: %s" n rule);
match Pf_qubes.Parse_qubes.parse_qubes ~number:n rule with
| Error e ->
Log.warn (fun f -> f "Error parsing rule %d: %s" n e);
Error e
| Ok rule ->
Log.debug (fun f ->
f "parsed rule: %a" Pf_qubes.Parse_qubes.pp_rule rule);
get_rule (n + 1) (rule :: l))
Log.debug (fun f -> f "rule %d does not exist; won't look for more" n);
Ok (List.rev l)
| Some rule ->
Log.debug (fun f -> f "rule %d: %s" n rule);
match Pf_qubes.Parse_qubes.parse_qubes ~number:n rule with
| Error e -> Log.warn (fun f -> f "Error parsing rule %d: %s" n e); Error e
| Ok rule ->
Log.debug (fun f -> f "parsed rule: %a" Pf_qubes.Parse_qubes.pp_rule rule);
get_rule (n+1) (rule :: l)
in
match get_rule 0 [] with
| Ok l -> l
| Error e ->
Log.warn (fun f ->
f "Defaulting to deny-all because of rule parse failure (%s)" e);
[
Pf_qubes.Parse_qubes.
{
action = Drop;
proto = None;
specialtarget = None;
dst = `any;
dstports = None;
icmp_type = None;
number = 0;
};
]
Log.warn (fun f -> f "Defaulting to deny-all because of rule parse failure (%s)" e);
[ Pf_qubes.Parse_qubes.({action = Drop;
proto = None;
specialtarget = None;
dst = `any;
dstports = None;
icmp_type = None;
number = 0;})]
let vifs client domid =
let open Lwt.Syntax in
match int_of_string_opt domid with
| None ->
Log.err (fun f -> f "Invalid domid %S" domid);
Lwt.return []
let vifs ~handle domid =
match String.to_int domid with
| None -> Log.err (fun f -> f "Invalid domid %S" domid); Lwt.return []
| Some domid ->
let path = Fmt.str "backend/vif/%d" domid in
let vifs_of_domain handle =
let* devices = directory ~handle path in
let ip_of_vif device_id =
match int_of_string_opt device_id with
| None ->
Log.err (fun f ->
f "Invalid device ID %S for domid %d" device_id domid);
Lwt.return_none
| Some device_id -> (
let vif = { ClientVif.domid; device_id } in
let get_client_ip () =
let* str =
Xen_os.Xs.read handle (Fmt.str "%s/%d/ip" path device_id)
in
let client_ip = List.hd (String.split_on_char ' ' str) in
(* NOTE(dinosaure): it's safe to use [List.hd] here,
[String.split_on_char] can not return an empty list. *)
Lwt.return_some (vif, Ipaddr.V4.of_string_exn client_ip)
in
Lwt.catch get_client_ip @@ function
| Xs_protocol.Enoent _ -> Lwt.return_none
| Ipaddr.Parse_error (msg, client_ip) ->
Log.err (fun f ->
f "Error parsing IP address of %a from %s: %s"
ClientVif.pp vif client_ip msg);
Lwt.return_none
| exn ->
Log.err (fun f ->
f "Error getting IP address of %a: %s" ClientVif.pp vif
(Printexc.to_string exn));
Lwt.return_none)
in
Lwt_list.filter_map_p ip_of_vif devices
in
Xen_os.Xs.immediate client vifs_of_domain
let path = Printf.sprintf "backend/vif/%d" domid in
directory ~handle path >>=
Lwt_list.filter_map_p (fun device_id ->
match String.to_int device_id with
| None -> Log.err (fun f -> f "Invalid device ID %S for domid %d" device_id domid); Lwt.return_none
| Some device_id ->
let vif = { ClientVif.domid; device_id } in
Lwt.try_bind
(fun () -> Xen_os.Xs.read handle (Printf.sprintf "%s/%d/ip" path device_id))
(fun client_ip ->
let client_ip' = match String.cuts ~sep:" " client_ip with
| [] -> Log.err (fun m -> m "unexpected empty list"); ""
| [ ip ] -> ip
| ip::rest ->
Log.warn (fun m -> m "ignoring IPs %s from %a, we support one IP per client"
(String.concat ~sep:" " rest) ClientVif.pp vif);
ip
in
match Ipaddr.V4.of_string client_ip' with
| Ok ip -> Lwt.return (Some (vif, ip))
| Error `Msg msg ->
Log.err (fun f -> f "Error parsing IP address of %a from %s: %s"
ClientVif.pp vif client_ip msg);
Lwt.return None
)
(function
| Xs_protocol.Enoent _ -> Lwt.return None
| ex ->
Log.err (fun f -> f "Error getting IP address of %a: %s"
ClientVif.pp vif (Printexc.to_string ex));
Lwt.return None
)
)
let watch_clients fn =
Xen_os.Xs.make () >>= fun xs ->
let backend_vifs = "backend/vif" in
Log.info (fun f -> f "Watching %s" backend_vifs);
Xen_os.Xs.wait xs (fun handle ->
Lwt.catch
(fun () -> directory ~handle backend_vifs)
(function Xs_protocol.Enoent _ -> Lwt.return [] | ex -> Lwt.fail ex)
>>= fun items ->
Xen_os.Xs.make () >>= fun xs ->
Lwt_list.map_p (vifs xs) items >>= fun items ->
fn (List.concat items |> VifMap.of_list) >>= fun () ->
(* Wait for further updates *)
Lwt.fail Xs_protocol.Eagain)
begin Lwt.catch
(fun () -> directory ~handle backend_vifs)
(function
| Xs_protocol.Enoent _ -> Lwt.return []
| ex -> Lwt.fail ex)
end >>= fun items ->
Lwt_list.map_p (vifs ~handle) items >>= fun items ->
fn (List.concat items |> VifMap.of_list);
(* Wait for further updates *)
Lwt.fail Xs_protocol.Eagain
)
type network_config = {
from_cmdline : bool;
(* Specify if we have network configuration from command line or from qubesDB*)
netvm_ip : Ipaddr.V4.t; (* The IP address of NetVM (our gateway) *)
our_ip : Ipaddr.V4.t; (* The IP address of our interface to NetVM *)
uplink_netvm_ip : Ipaddr.V4.t; (* The IP address of NetVM (our gateway) *)
uplink_our_ip : Ipaddr.V4.t; (* The IP address of our interface to NetVM *)
clients_our_ip : Ipaddr.V4.t; (* The IP address of our interface to our client VMs (their gateway) *)
dns : Ipaddr.V4.t;
dns2 : Ipaddr.V4.t;
}
@ -146,36 +135,32 @@ let try_read_network_config db =
let get name =
match DB.KeyMap.find_opt name db with
| None -> raise (Missing_key name)
| Some value -> Ipaddr.V4.of_string_exn value
in
let our_ip = get "/qubes-ip" in
(* - IP address for this VM (only when VM has netvm set) *)
let netvm_ip = get "/qubes-gateway" in
(* - default gateway IP (only when VM has netvm set); VM should add host route to this address directly via eth0 (or whatever default interface name is) *)
let dns = get "/qubes-primary-dns" in
let dns2 = get "/qubes-secondary-dns" in
{ from_cmdline = false; netvm_ip; our_ip; dns; dns2 }
| Some value -> value in
let uplink_our_ip = get "/qubes-ip" |> Ipaddr.V4.of_string_exn in
let uplink_netvm_ip = get "/qubes-gateway" |> Ipaddr.V4.of_string_exn in
let clients_our_ip = get "/qubes-netvm-gateway" |> Ipaddr.V4.of_string_exn in
let dns = get "/qubes-primary-dns" |> Ipaddr.V4.of_string_exn in
let dns2 = get "/qubes-secondary-dns" |> Ipaddr.V4.of_string_exn in
Log.info (fun f -> f "@[<v2>Got network configuration from QubesDB:@,\
NetVM IP on uplink network: %a@,\
Our IP on uplink network: %a@,\
Our IP on client networks: %a@,\
DNS primary resolver: %a@,\
DNS secondary resolver: %a@]"
Ipaddr.V4.pp uplink_netvm_ip
Ipaddr.V4.pp uplink_our_ip
Ipaddr.V4.pp clients_our_ip
Ipaddr.V4.pp dns
Ipaddr.V4.pp dns2);
{ uplink_netvm_ip; uplink_our_ip; clients_our_ip ; dns ; dns2 }
let read_network_config qubesDB =
let rec aux bindings =
try Lwt.return (try_read_network_config bindings)
with Missing_key key ->
Log.warn (fun f ->
f "QubesDB key %S not (yet) present; waiting for QubesDB to change..."
key);
Log.warn (fun f -> f "QubesDB key %S not (yet) present; waiting for QubesDB to change..." key);
DB.after qubesDB bindings >>= aux
in
aux (DB.bindings qubesDB)
let print_network_config config =
Log.info (fun f ->
f
"@[<v2>Current network configuration (QubesDB or command line):@,\
NetVM IP on uplink network: %a@,\
Our IP on client networks: %a@,\
DNS primary resolver: %a@,\
DNS secondary resolver: %a@]"
Ipaddr.V4.pp config.netvm_ip Ipaddr.V4.pp config.our_ip Ipaddr.V4.pp
config.dns Ipaddr.V4.pp config.dns2)
let set_iptables_error db = Qubes.DB.write db "/qubes-iptables-error"

38
dao.mli
View File

@ -4,43 +4,39 @@
(** Wrapper for XenStore and QubesDB databases. *)
module ClientVif : sig
type t = { domid : int; device_id : int }
type t = {
domid : int;
device_id : int;
}
val pp : t Fmt.t
end
module VifMap : sig
include Map.S with type key = ClientVif.t
val find : key -> 'a t -> 'a option
end
val watch_clients : (Ipaddr.V4.t VifMap.t -> unit Lwt.t) -> 'a Lwt.t
(** [watch_clients fn] calls [fn clients] with the list of backend clients in
XenStore, and again each time XenStore updates. *)
val watch_clients : (Ipaddr.V4.t VifMap.t -> unit) -> 'a Lwt.t
(** [watch_clients fn] calls [fn clients] with the list of backend clients
in XenStore, and again each time XenStore updates. *)
type network_config = {
from_cmdline : bool;
(* Specify if we have network configuration from command line or from qubesDB*)
netvm_ip : Ipaddr.V4.t; (* The IP address of NetVM (our gateway) *)
our_ip : Ipaddr.V4.t; (* The IP address of our interface to NetVM *)
uplink_netvm_ip : Ipaddr.V4.t; (* The IP address of NetVM (our gateway) *)
uplink_our_ip : Ipaddr.V4.t; (* The IP address of our interface to NetVM *)
clients_our_ip : Ipaddr.V4.t; (* The IP address of our interface to our client VMs (their gateway) *)
dns : Ipaddr.V4.t;
dns2 : Ipaddr.V4.t;
}
val read_network_config : Qubes.DB.t -> network_config Lwt.t
(** [read_network_config db] fetches the configuration from QubesDB. If it isn't
there yet, it waits until it is. *)
(** [read_network_config db] fetches the configuration from QubesDB.
If it isn't there yet, it waits until it is. *)
val db_root : Ipaddr.V4.t -> string
(** Returns the root path of the firewall rules in the QubesDB for a given IP
address. *)
(** Returns the root path of the firewall rules in the QubesDB for a given IP address. *)
val read_rules :
string Qubes.DB.KeyMap.t -> Ipaddr.V4.t -> Pf_qubes.Parse_qubes.rule list
(** [read_rules bindings ip] extracts firewall rule information for [ip] from
[bindings]. If any rules fail to parse, it will return only one rule denying
all traffic. *)
val read_rules : string Qubes.DB.KeyMap.t -> Ipaddr.V4.t -> Pf_qubes.Parse_qubes.rule list
(** [read_rules bindings ip] extracts firewall rule information for [ip] from [bindings].
If any rules fail to parse, it will return only one rule denying all traffic. *)
val print_network_config : network_config -> unit
val set_iptables_error : Qubes.DB.t -> string -> unit Lwt.t

View File

@ -1,635 +0,0 @@
open Lwt.Infix
open Fw_utils
module Netback = Backend.Make (Xenstore.Make (Xen_os.Xs))
module ClientEth = Ethernet.Make (Netback)
module UplinkEth = Ethernet.Make (Netif)
let src = Logs.Src.create "dispatcher" ~doc:"Networking dispatch"
module Log = (val Logs.src_log src : Logs.LOG)
module Arp = Arp.Make (UplinkEth)
module I = Static_ipv4.Make (UplinkEth) (Arp)
module U = Udp.Make (I)
class client_iface eth ~domid ~gateway_ip ~client_ip client_mac : client_link =
let log_header = Fmt.str "dom%d:%a" domid Ipaddr.V4.pp client_ip in
object
val mutable rules = []
method get_rules = rules
method set_rules new_db = rules <- Dao.read_rules new_db client_ip
method my_mac = ClientEth.mac eth
method other_mac = client_mac
method my_ip = gateway_ip
method other_ip = client_ip
method writev proto fillfn =
Lwt.catch
(fun () ->
ClientEth.write eth client_mac proto fillfn >|= function
| Ok () -> ()
| Error e ->
Log.err (fun f ->
f "error trying to send to client: @[%a@]" ClientEth.pp_error
e))
(fun ex ->
(* Usually Netback_shutdown, because the client disconnected *)
Log.err (fun f ->
f "uncaught exception trying to send to client: @[%s@]"
(Printexc.to_string ex));
Lwt.return_unit)
method log_header = log_header
end
class netvm_iface eth mac ~my_ip ~other_ip : interface =
object
method my_mac = UplinkEth.mac eth
method my_ip = my_ip
method other_ip = other_ip
method writev ethertype fillfn =
Lwt.catch
(fun () ->
mac >>= fun dst ->
UplinkEth.write eth dst ethertype fillfn
>|= or_raise "Write to uplink" UplinkEth.pp_error)
(fun ex ->
Log.err (fun f ->
f "uncaught exception trying to send to uplink: @[%s@]"
(Printexc.to_string ex));
Lwt.return_unit)
end
type uplink = {
net : Netif.t;
eth : UplinkEth.t;
arp : Arp.t;
interface : interface;
mutable fragments : Fragments.Cache.t;
ip : I.t;
udp : U.t;
}
type t = {
uplink_connected : unit Lwt_condition.t;
uplink_disconnect : unit Lwt_condition.t;
uplink_disconnected : unit Lwt_condition.t;
mutable config : Dao.network_config;
clients : Client_eth.t;
nat : My_nat.t;
mutable uplink : uplink option;
}
let create ~config ~clients ~nat ~uplink =
{
uplink_connected = Lwt_condition.create ();
uplink_disconnect = Lwt_condition.create ();
uplink_disconnected = Lwt_condition.create ();
config;
clients;
nat;
uplink;
}
let update t ~config ~uplink =
t.config <- config;
t.uplink <- uplink;
Lwt.return_unit
let target t buf =
let dst_ip = buf.Ipv4_packet.dst in
match Client_eth.lookup t.clients dst_ip with
| Some client_link -> Some (client_link :> interface)
| None -> (
(* if dest is not a client, transfer it to our uplink *)
match t.uplink with
| None -> (
match Client_eth.lookup t.clients t.config.netvm_ip with
| Some uplink -> Some (uplink :> interface)
| None ->
Log.err (fun f ->
f
"We have a command line configuration %a but it's \
currently not connected to us (please check its netvm \
property)...%!"
Ipaddr.V4.pp t.config.netvm_ip);
None)
| Some uplink -> Some uplink.interface)
let add_client t = Client_eth.add_client t.clients
let remove_client t = Client_eth.remove_client t.clients
let classify t ip =
if ip = Ipaddr.V4 t.config.our_ip then `Firewall
else if ip = Ipaddr.V4 t.config.netvm_ip then `NetVM
else (Client_eth.classify t.clients ip :> Packet.host)
let resolve t = function
| `Firewall -> Ipaddr.V4 t.config.our_ip
| `NetVM -> Ipaddr.V4 t.config.netvm_ip
| #Client_eth.host as host -> Client_eth.resolve t.clients host
(* Transmission *)
let transmit_ipv4 packet iface =
Lwt.catch
(fun () ->
let fragments = ref [] in
iface#writev `IPv4 (fun b ->
match Nat_packet.into_cstruct packet b with
| Error e ->
Log.warn (fun f ->
f "Failed to write packet to %a: %a" Ipaddr.V4.pp
iface#other_ip Nat_packet.pp_error e);
0
| Ok (n, frags) ->
fragments := frags;
n)
>>= fun () ->
Lwt_list.iter_s
(fun f ->
let size = Cstruct.length f in
iface#writev `IPv4 (fun b ->
Cstruct.blit f 0 b 0 size;
size))
!fragments)
(fun ex ->
Log.warn (fun f ->
f "Failed to write packet to %a: %s" Ipaddr.V4.pp iface#other_ip
(Printexc.to_string ex));
Lwt.return_unit)
let forward_ipv4 t packet =
let (`IPv4 (ip, _)) = packet in
Lwt.catch
(fun () ->
match target t ip with
| Some iface -> transmit_ipv4 packet iface
| None -> Lwt.return_unit)
(fun ex ->
let dst_ip = ip.Ipv4_packet.dst in
Log.warn (fun f ->
f "Failed to lookup for target %a: %s" Ipaddr.V4.pp dst_ip
(Printexc.to_string ex));
Lwt.return_unit)
(* NAT *)
let translate t packet = My_nat.translate t.nat packet
(* Add a NAT rule for the endpoints in this frame, via a random port on the firewall. *)
let add_nat_and_forward_ipv4 t packet =
let xl_host = t.config.our_ip in
match My_nat.add_nat_rule_and_translate t.nat ~xl_host `NAT packet with
| Ok packet -> forward_ipv4 t packet
| Error e ->
Log.warn (fun f ->
f "Failed to add NAT rewrite rule: %s (%a)" e Nat_packet.pp packet);
Lwt.return_unit
(* Add a NAT rule to redirect this conversation to [host:port] instead of us. *)
let nat_to t ~host ~port packet =
match resolve t host with
| Ipaddr.V6 _ ->
Log.warn (fun f -> f "Cannot NAT with IPv6");
Lwt.return_unit
| Ipaddr.V4 target -> (
let xl_host = t.config.our_ip in
match
My_nat.add_nat_rule_and_translate t.nat ~xl_host
(`Redirect (target, port))
packet
with
| Ok packet -> forward_ipv4 t packet
| Error e ->
Log.warn (fun f ->
f "Failed to add NAT redirect rule: %s (%a)" e Nat_packet.pp
packet);
Lwt.return_unit)
let apply_rules t (rules : ('a, 'b) Packet.t -> Packet.action Lwt.t) ~dst
(annotated_packet : ('a, 'b) Packet.t) : unit Lwt.t =
let packet = Packet.to_mirage_nat_packet annotated_packet in
rules annotated_packet >>= fun action ->
match (action, dst) with
| `Accept, `Client client_link -> transmit_ipv4 packet client_link
| `Accept, (`External _ | `NetVM) -> (
match t.uplink with
| Some uplink -> transmit_ipv4 packet uplink.interface
| None -> (
match Client_eth.lookup t.clients t.config.netvm_ip with
| Some iface -> transmit_ipv4 packet iface
| None ->
Log.warn (fun f ->
f "No output interface for %a : drop" Nat_packet.pp packet);
Lwt.return_unit))
| `Accept, `Firewall ->
Log.warn (fun f ->
f "Bad rule: firewall can't accept packets %a" Nat_packet.pp packet);
Lwt.return_unit
| `NAT, _ ->
Log.debug (fun f -> f "adding NAT rule for %a" Nat_packet.pp packet);
add_nat_and_forward_ipv4 t packet
| `NAT_to (host, port), _ -> nat_to t packet ~host ~port
| `Drop reason, _ ->
Log.debug (fun f ->
f "Dropped packet (%s) %a" reason Nat_packet.pp packet);
Lwt.return_unit
let ipv4_from_netvm t packet =
match Memory_pressure.status () with
| `Memory_critical -> Lwt.return_unit
| `Ok -> (
let (`IPv4 (ip, _transport)) = packet in
let src = classify t (Ipaddr.V4 ip.Ipv4_packet.src) in
let dst = classify t (Ipaddr.V4 ip.Ipv4_packet.dst) in
match Packet.of_mirage_nat_packet ~src ~dst packet with
| None -> Lwt.return_unit
| Some _ -> (
match src with
| `Client _ | `Firewall ->
Log.warn (fun f ->
f "Frame from NetVM has internal source IP address! %a"
Nat_packet.pp packet);
Lwt.return_unit
| (`External _ | `NetVM) as src -> (
match translate t packet with
| Some frame -> forward_ipv4 t frame
| None -> (
match Packet.of_mirage_nat_packet ~src ~dst packet with
| None -> Lwt.return_unit
| Some packet -> apply_rules t Rules.from_netvm ~dst packet)))
)
let ipv4_from_client resolver dns_servers t ~src packet =
match Memory_pressure.status () with
| `Memory_critical -> Lwt.return_unit
| `Ok -> (
(* Check for existing NAT entry for this packet *)
match translate t packet with
| Some frame ->
forward_ipv4 t frame (* Some existing connection or redirect *)
| None -> (
(* No existing NAT entry. Check the firewall rules. *)
let (`IPv4 (ip, _transport)) = packet in
match classify t (Ipaddr.V4 ip.Ipv4_packet.src) with
| `Client _ | `Firewall -> (
let dst = classify t (Ipaddr.V4 ip.Ipv4_packet.dst) in
match
Packet.of_mirage_nat_packet ~src:(`Client src) ~dst packet
with
| None -> Lwt.return_unit
| Some firewall_packet ->
apply_rules t
(Rules.from_client resolver dns_servers)
~dst firewall_packet)
| `NetVM -> ipv4_from_netvm t packet
| `External _ ->
Log.warn (fun f ->
f "Frame from Inside has external source IP address! %a"
Nat_packet.pp packet);
Lwt.return_unit))
(** Handle an ARP message from the client. *)
let client_handle_arp ~fixed_arp ~iface request =
match Arp_packet.decode request with
| Error e ->
Log.warn (fun f ->
f "Ignored unknown ARP message: %a" Arp_packet.pp_error e);
Lwt.return_unit
| Ok arp -> (
match Client_eth.ARP.input fixed_arp arp with
| None -> Lwt.return_unit
| Some response ->
Lwt.catch
(fun () ->
iface#writev `ARP (fun b ->
Arp_packet.encode_into response b;
Arp_packet.size))
(fun ex ->
Log.warn (fun f ->
f "Failed to write APR to %a: %s" Ipaddr.V4.pp iface#other_ip
(Printexc.to_string ex));
Lwt.return_unit))
(** Handle an IPv4 packet from the client. *)
let client_handle_ipv4 get_ts cache ~iface ~router dns_client dns_servers packet
=
let cache', r = Nat_packet.of_ipv4_packet !cache ~now:(get_ts ()) packet in
cache := cache';
match r with
| Error e ->
Log.warn (fun f ->
f "Ignored unknown IPv4 message: %a" Nat_packet.pp_error e);
Lwt.return_unit
| Ok None -> Lwt.return_unit
| Ok (Some packet) ->
let (`IPv4 (ip, _)) = packet in
let src = ip.Ipv4_packet.src in
if src = iface#other_ip then
ipv4_from_client dns_client dns_servers router ~src:iface packet
else if iface#other_ip = router.config.netvm_ip then
(* This can occurs when used with *BSD as netvm (and a gateway is set) *)
ipv4_from_netvm router packet
else (
Log.warn (fun f ->
f "Incorrect source IP %a in IP packet from %a (dropping)"
Ipaddr.V4.pp src Ipaddr.V4.pp iface#other_ip);
Lwt.return_unit)
(** Connect to a new client's interface and listen for incoming frames and
firewall rule changes. *)
let conf_vif get_ts vif backend client_eth dns_client dns_servers ~client_ip
~iface ~router ~cleanup_tasks qubesDB () =
let { Dao.ClientVif.domid; device_id } = vif in
Log.info (fun f ->
f "Client %d:%d (IP: %s) ready" domid device_id
(Ipaddr.V4.to_string client_ip));
(* update the rules whenever QubesDB notices a change for this IP *)
let qubesdb_updater =
Lwt.catch
(fun () ->
let rec update current_db current_rules =
Qubes.DB.got_new_commit qubesDB (Dao.db_root client_ip) current_db
>>= fun new_db ->
iface#set_rules new_db;
let new_rules = iface#get_rules in
if current_rules = new_rules then
Log.info (fun m ->
m "Rules did not change for %s" (Ipaddr.V4.to_string client_ip))
else (
Log.info (fun m ->
m "New firewall rules for %s@.%a"
(Ipaddr.V4.to_string client_ip)
Fmt.(list ~sep:(any "@.") Pf_qubes.Parse_qubes.pp_rule)
new_rules);
(* empty NAT table if rules are updated: they might deny old connections *)
My_nat.remove_connections router.nat client_ip);
update new_db new_rules
in
update Qubes.DB.KeyMap.empty [])
(function Lwt.Canceled -> Lwt.return_unit | e -> Lwt.fail e)
in
Cleanup.on_cleanup cleanup_tasks (fun () -> Lwt.cancel qubesdb_updater);
let fixed_arp = Client_eth.ARP.create ~net:client_eth iface in
let fragment_cache = ref (Fragments.Cache.empty (256 * 1024)) in
let listener =
Lwt.catch
(fun () ->
Netback.listen backend ~header_size:Ethernet.Packet.sizeof_ethernet
(fun frame ->
match Ethernet.Packet.of_cstruct frame with
| Error err ->
Log.warn (fun f -> f "Invalid Ethernet frame: %s" err);
Lwt.return_unit
| Ok (eth, payload) -> (
match eth.Ethernet.Packet.ethertype with
| `ARP -> client_handle_arp ~fixed_arp ~iface payload
| `IPv4 ->
client_handle_ipv4 get_ts fragment_cache ~iface ~router
dns_client dns_servers payload
| `IPv6 -> Lwt.return_unit (* TODO: oh no! *)))
>|= or_raise "Listen on client interface" Netback.pp_error)
(function Lwt.Canceled -> Lwt.return_unit | e -> Lwt.fail e)
in
Cleanup.on_cleanup cleanup_tasks (fun () -> Lwt.cancel listener);
(* NOTE(dinosaure): [qubes_updater] and [listener] can be forgotten, our [cleanup_task]
will cancel them if the client is disconnected. *)
Lwt.async (fun () -> Lwt.pick [ qubesdb_updater; listener ]);
Lwt.return_unit
(** A new client VM has been found in XenStore. Find its interface and connect
to it. *)
let add_client get_ts dns_client dns_servers ~router vif client_ip qubesDB =
let open Lwt.Syntax in
let cleanup_tasks = Cleanup.create () in
Log.info (fun f ->
f "add client vif %a with IP %a" Dao.ClientVif.pp vif Ipaddr.V4.pp
client_ip);
let { Dao.ClientVif.domid; device_id } = vif in
let* backend = Netback.make ~domid ~device_id in
let* eth = ClientEth.connect backend in
let client_mac = Netback.frontend_mac backend in
let client_eth = router.clients in
let gateway_ip = Client_eth.client_gw client_eth in
let iface = new client_iface eth ~domid ~gateway_ip ~client_ip client_mac in
Cleanup.on_cleanup cleanup_tasks (fun () -> remove_client router iface);
Lwt.async (fun () ->
Lwt.catch
(fun () -> add_client router iface)
(fun ex ->
Log.warn (fun f ->
f "Error with client %a: %s" Dao.ClientVif.pp vif
(Printexc.to_string ex));
Lwt.return_unit));
let* () =
Lwt.catch
(conf_vif get_ts vif backend client_eth dns_client dns_servers ~client_ip
~iface ~router ~cleanup_tasks qubesDB)
@@ fun exn ->
Log.warn (fun f ->
f "Error with client %a: %s" Dao.ClientVif.pp vif
(Printexc.to_string exn));
Lwt.return_unit
in
Lwt.return cleanup_tasks
(** Watch XenStore for notifications of new clients. *)
let wait_clients get_ts dns_client dns_servers qubesDB router =
let open Lwt.Syntax in
let clients : Cleanup.t Dao.VifMap.t ref = ref Dao.VifMap.empty in
Dao.watch_clients @@ fun new_set ->
(* Check for removed clients *)
let clean_up_clients key cleanup =
if not (Dao.VifMap.mem key new_set) then (
clients := !clients |> Dao.VifMap.remove key;
Log.info (fun f -> f "client %a has gone" Dao.ClientVif.pp key);
Cleanup.cleanup cleanup)
in
Dao.VifMap.iter clean_up_clients !clients;
(* Check for added clients *)
let rec go seq =
match Seq.uncons seq with
| None -> Lwt.return_unit
| Some ((key, ipaddr), seq) when not (Dao.VifMap.mem key !clients) ->
let* cleanup =
add_client get_ts dns_client dns_servers ~router key ipaddr qubesDB
in
Log.debug (fun f -> f "client %a arrived" Dao.ClientVif.pp key);
clients := Dao.VifMap.add key cleanup !clients;
go seq
| Some (_, seq) -> go seq
in
go (Dao.VifMap.to_seq new_set)
let send_dns_client_query t ~src_port ~dst ~dst_port buf =
match t.uplink with
| None ->
Log.err (fun f -> f "No uplink interface");
Lwt.return (Error (`Msg "failure"))
| Some uplink ->
Lwt.catch
(fun () ->
U.write ~src_port ~dst ~dst_port uplink.udp (Cstruct.of_string buf)
>|= function
| Error s ->
Log.err (fun f -> f "error sending udp packet: %a" U.pp_error s);
Error (`Msg "failure")
| Ok () -> Ok ())
(fun ex ->
Log.err (fun f ->
f
"uncaught exception trying to send DNS request to uplink: \
@[%s@]"
(Printexc.to_string ex));
Lwt.return (Error (`Msg "DNS request not sent")))
(** Wait for packet from our uplink (we must have an uplink here...). *)
let rec uplink_listen get_ts dns_responses router =
Lwt_condition.wait router.uplink_connected >>= fun () ->
match router.uplink with
| None ->
Log.err (fun f ->
f "Uplink is connected but not found in the router, retrying...%!");
uplink_listen get_ts dns_responses router
| Some uplink ->
let listen =
Lwt.catch
(fun () ->
Netif.listen uplink.net ~header_size:Ethernet.Packet.sizeof_ethernet
(fun frame ->
(* Handle one Ethernet frame from NetVM *)
UplinkEth.input uplink.eth ~arpv4:(Arp.input uplink.arp)
~ipv4:(fun ip ->
let cache, r =
Nat_packet.of_ipv4_packet uplink.fragments
~now:(get_ts ()) ip
in
uplink.fragments <- cache;
match r with
| Error e ->
Log.warn (fun f ->
f "Ignored unknown IPv4 message from uplink: %a"
Nat_packet.pp_error e);
Lwt.return ()
| Ok None -> Lwt.return_unit
| Ok (Some (`IPv4 (header, packet))) -> (
let open Udp_packet in
Log.debug (fun f ->
f "received ipv4 packet from %a on uplink"
Ipaddr.V4.pp header.Ipv4_packet.src);
match packet with
| `UDP (header, packet)
when My_nat.dns_port router.nat header.dst_port ->
Log.debug (fun f ->
f
"found a DNS packet whose dst_port (%d) was \
in the list of dns_client ports"
header.dst_port);
Lwt_mvar.put dns_responses
(header, Cstruct.to_string packet)
| _ -> ipv4_from_netvm router (`IPv4 (header, packet))))
~ipv6:(fun _ip -> Lwt.return_unit)
frame)
>|= or_raise "Uplink listen loop" Netif.pp_error)
(function
| Lwt.Canceled ->
(* We can be cancelled if reconnect_uplink is achieved (via the Lwt_condition), so we need to disconnect and broadcast when it's done
currently we delay 1s as Netif.disconnect is non-blocking... (need to fix upstream?) *)
Log.info (fun f -> f "disconnecting from our uplink");
U.disconnect uplink.udp >>= fun () ->
I.disconnect uplink.ip >>= fun () ->
(* mutable fragments : Fragments.Cache.t; *)
(* interface : interface; *)
Arp.disconnect uplink.arp >>= fun () ->
UplinkEth.disconnect uplink.eth >>= fun () ->
Netif.disconnect uplink.net >>= fun () ->
Lwt_condition.broadcast router.uplink_disconnected ();
Lwt.return_unit
| e -> Lwt.fail e)
in
let reconnect_uplink =
Lwt_condition.wait router.uplink_disconnect >>= fun () ->
Log.info (fun f -> f "we need to reconnect to the new uplink");
Lwt.return_unit
in
Lwt.pick [ listen; reconnect_uplink ] >>= fun () ->
uplink_listen get_ts dns_responses router
(** Connect to our uplink backend (we must have an uplink here...). *)
let connect config =
let my_ip = config.Dao.our_ip in
let gateway = config.Dao.netvm_ip in
Netif.connect "0" >>= fun net ->
UplinkEth.connect net >>= fun eth ->
Arp.connect eth >>= fun arp ->
Arp.add_ip arp my_ip >>= fun () ->
let cidr = Ipaddr.V4.Prefix.make 0 my_ip in
I.connect ~cidr ~gateway eth arp >>= fun ip ->
U.connect ip >>= fun udp ->
let netvm_mac =
Arp.query arp gateway >>= function
| Error e ->
Log.err (fun f -> f "Getting MAC of our NetVM: %a" Arp.pp_error e);
(* This mac address is a special address used by Qubes when the device
is not managed by Qubes itself. This can occurs inside a service
AppVM (e.g. VPN) when the service creates a new interface. *)
Lwt.return (Macaddr.of_string_exn "fe:ff:ff:ff:ff:ff")
| Ok mac -> Lwt.return mac
in
let interface =
new netvm_iface eth netvm_mac ~my_ip ~other_ip:config.Dao.netvm_ip
in
let fragments = Fragments.Cache.empty (256 * 1024) in
Lwt.return { net; eth; arp; interface; fragments; ip; udp }
(** Wait Xenstore for our uplink changes (we must have an uplink here...). *)
let uplink_wait_update qubesDB router =
let rec aux current_db =
let netvm = "/qubes-gateway" in
Log.info (fun f -> f "Waiting for netvm changes to %S...%!" netvm);
Qubes.DB.after qubesDB current_db >>= fun new_db ->
(match (router.uplink, Qubes.DB.KeyMap.find_opt netvm new_db) with
| Some uplink, Some netvm
when not
(String.equal netvm
(Ipaddr.V4.to_string uplink.interface#other_ip)) ->
Log.info (fun f ->
f "Our netvm IP has changed, before it was %s, now it's: %s%!"
(Ipaddr.V4.to_string uplink.interface#other_ip)
netvm);
Lwt_condition.broadcast router.uplink_disconnect ();
(* wait for uplink disconnexion *)
Lwt_condition.wait router.uplink_disconnected >>= fun () ->
Dao.read_network_config qubesDB >>= fun config ->
Dao.print_network_config config;
connect config >>= fun uplink ->
update router ~config ~uplink:(Some uplink) >>= fun () ->
Lwt_condition.broadcast router.uplink_connected ();
Lwt.return_unit
| None, Some _ ->
(* a new interface is attributed to qubes-mirage-firewall *)
Log.info (fun f -> f "Going from netvm not connected to %s%!" netvm);
Dao.read_network_config qubesDB >>= fun config ->
Dao.print_network_config config;
connect config >>= fun uplink ->
update router ~config ~uplink:(Some uplink) >>= fun () ->
Lwt_condition.broadcast router.uplink_connected ();
Lwt.return_unit
| Some _, None ->
(* This currently is never triggered :( *)
Log.info (fun f ->
f "TODO: Our netvm disapeared, troubles are coming!%!");
Lwt.return_unit
| Some _, Some _ (* The new netvm IP is unchanged (it's our old netvm IP) *)
| None, None ->
Log.info (fun f ->
f "QubesDB has changed but not the situation of our netvm!%!");
Lwt.return_unit)
>>= fun () -> aux new_db
in
aux Qubes.DB.KeyMap.empty

129
firewall.ml Normal file
View File

@ -0,0 +1,129 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Packet
open Lwt.Infix
let src = Logs.Src.create "firewall" ~doc:"Packet handler"
module Log = (val Logs.src_log src : Logs.LOG)
(* Transmission *)
let transmit_ipv4 packet iface =
Lwt.catch
(fun () ->
let fragments = ref [] in
iface#writev `IPv4 (fun b ->
match Nat_packet.into_cstruct packet b with
| Error e ->
Log.warn (fun f -> f "Failed to write packet to %a: %a"
Ipaddr.V4.pp iface#other_ip
Nat_packet.pp_error e);
0
| Ok (n, frags) -> fragments := frags ; n) >>= fun () ->
Lwt_list.iter_s (fun f ->
let size = Cstruct.length f in
iface#writev `IPv4 (fun b -> Cstruct.blit f 0 b 0 size ; size))
!fragments)
(fun ex ->
Log.warn (fun f -> f "Failed to write packet to %a: %s"
Ipaddr.V4.pp iface#other_ip
(Printexc.to_string ex));
Lwt.return_unit
)
let forward_ipv4 t packet =
let `IPv4 (ip, _) = packet in
match Router.target t ip with
| Some iface -> transmit_ipv4 packet iface
| None -> Lwt.return_unit
(* NAT *)
let translate t packet =
My_nat.translate t.Router.nat packet
(* Add a NAT rule for the endpoints in this frame, via a random port on the firewall. *)
let add_nat_and_forward_ipv4 t packet =
let open Router in
let xl_host = t.uplink#my_ip in
My_nat.add_nat_rule_and_translate t.nat t.ports ~xl_host `NAT packet >>= function
| Ok packet -> forward_ipv4 t packet
| Error e ->
Log.warn (fun f -> f "Failed to add NAT rewrite rule: %s (%a)" e Nat_packet.pp packet);
Lwt.return_unit
(* Add a NAT rule to redirect this conversation to [host:port] instead of us. *)
let nat_to t ~host ~port packet =
let open Router in
match resolve t host with
| Ipaddr.V6 _ -> Log.warn (fun f -> f "Cannot NAT with IPv6"); Lwt.return_unit
| Ipaddr.V4 target ->
let xl_host = t.uplink#my_ip in
My_nat.add_nat_rule_and_translate t.nat t.ports ~xl_host (`Redirect (target, port)) packet >>= function
| Ok packet -> forward_ipv4 t packet
| Error e ->
Log.warn (fun f -> f "Failed to add NAT redirect rule: %s (%a)" e Nat_packet.pp packet);
Lwt.return_unit
let apply_rules t (rules : ('a, 'b) Packet.t -> Packet.action Lwt.t) ~dst (annotated_packet : ('a, 'b) Packet.t) : unit Lwt.t =
let packet = to_mirage_nat_packet annotated_packet in
rules annotated_packet >>= fun action ->
match action, dst with
| `Accept, `Client client_link -> transmit_ipv4 packet client_link
| `Accept, (`External _ | `NetVM) -> transmit_ipv4 packet t.Router.uplink
| `Accept, `Firewall ->
Log.warn (fun f -> f "Bad rule: firewall can't accept packets %a" Nat_packet.pp packet);
Lwt.return_unit
| `NAT, _ ->
Log.debug (fun f -> f "adding NAT rule for %a" Nat_packet.pp packet);
add_nat_and_forward_ipv4 t packet
| `NAT_to (host, port), _ -> nat_to t packet ~host ~port
| `Drop reason, _ ->
Log.debug (fun f -> f "Dropped packet (%s) %a" reason Nat_packet.pp packet);
Lwt.return_unit
let handle_low_memory t =
match Memory_pressure.status () with
| `Memory_critical -> (* TODO: should happen before copying and async *)
Log.warn (fun f -> f "Memory low - dropping packet and resetting NAT table");
My_nat.reset t.Router.nat t.Router.ports >|= fun () ->
`Memory_critical
| `Ok -> Lwt.return `Ok
let ipv4_from_client resolver dns_servers t ~src packet =
handle_low_memory t >>= function
| `Memory_critical -> Lwt.return_unit
| `Ok ->
(* Check for existing NAT entry for this packet *)
translate t packet >>= function
| Some frame -> forward_ipv4 t frame (* Some existing connection or redirect *)
| None ->
(* No existing NAT entry. Check the firewall rules. *)
let `IPv4 (ip, _transport) = packet in
let dst = Router.classify t (Ipaddr.V4 ip.Ipv4_packet.dst) in
match of_mirage_nat_packet ~src:(`Client src) ~dst packet with
| None -> Lwt.return_unit
| Some firewall_packet -> apply_rules t (Rules.from_client resolver dns_servers) ~dst firewall_packet
let ipv4_from_netvm t packet =
handle_low_memory t >>= function
| `Memory_critical -> Lwt.return_unit
| `Ok ->
let `IPv4 (ip, _transport) = packet in
let src = Router.classify t (Ipaddr.V4 ip.Ipv4_packet.src) in
let dst = Router.classify t (Ipaddr.V4 ip.Ipv4_packet.dst) in
match Packet.of_mirage_nat_packet ~src ~dst packet with
| None -> Lwt.return_unit
| Some _ ->
match src with
| `Client _ | `Firewall ->
Log.warn (fun f -> f "Frame from NetVM has internal source IP address! %a" Nat_packet.pp packet);
Lwt.return_unit
| `External _ | `NetVM as src ->
translate t packet >>= function
| Some frame -> forward_ipv4 t frame
| None ->
match Packet.of_mirage_nat_packet ~src ~dst packet with
| None -> Lwt.return_unit
| Some packet -> apply_rules t Rules.from_netvm ~dst packet

13
firewall.mli Normal file
View File

@ -0,0 +1,13 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** Classify IP packets, apply rules and send as appropriate. *)
val ipv4_from_netvm : Router.t -> Nat_packet.t -> unit Lwt.t
(** Handle a packet from the outside world (this module will validate the source IP). *)
(* TODO the function type is a workaround, rework the module dependencies / functors to get rid of it *)
val ipv4_from_client : ([ `host ] Domain_name.t -> (int32 * Ipaddr.V4.Set.t, [> `Msg of string ]) result Lwt.t) ->
Ipaddr.V4.t list -> Router.t -> src:Fw_utils.client_link -> Nat_packet.t -> unit Lwt.t
(** Handle a packet from a client. Caller must check the source IP matches the client's
before calling this. *)

32
frameQ.ml Normal file
View File

@ -0,0 +1,32 @@
(* Copyright (C) 2016, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
let src = Logs.Src.create "frameQ" ~doc:"Interface output queue"
module Log = (val Logs.src_log src : Logs.LOG)
type t = {
name : string;
mutable items : int;
}
let create name = { name; items = 0 }
(* Note: the queue is only used if we already filled the transmit buffer. *)
let max_qlen = 10
let send q fn =
if q.items = max_qlen then (
Log.warn (fun f -> f "Maximum queue length exceeded for %s: dropping frame" q.name);
Lwt.return_unit
) else (
let sent = fn () in
if Lwt.state sent = Lwt.Sleep then (
q.items <- q.items + 1;
Log.info (fun f -> f "Queue length for %s: incr to %d" q.name q.items);
Lwt.on_termination sent (fun () ->
q.items <- q.items - 1;
Log.info (fun f -> f "Queue length for %s: decr to %d" q.name q.items);
)
);
sent
)

15
frameQ.mli Normal file
View File

@ -0,0 +1,15 @@
(* Copyright (C) 2016, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** Keep track of the queue length for output buffers. *)
type t
val create : string -> t
(** [create name] is a new empty queue. [name] is used in log messages. *)
val send : t -> (unit -> unit Lwt.t) -> unit Lwt.t
(** [send t fn] checks that the queue isn't overloaded and calls [fn ()] if it's OK.
The item is considered to be queued until the result of [fn] has resolved.
In the case of mirage-net-xen's [writev], this happens when the frame has been
added to the ring (not when it is consumed), which is fine for us. *)

View File

@ -3,6 +3,21 @@
(** General utility functions. *)
module IpMap = struct
include Map.Make(Ipaddr.V4)
let find x map =
try Some (find x map)
with Not_found -> None
end
module Int = struct
type t = int
let compare (a:t) (b:t) = compare a b
end
module IntSet = Set.Make(Int)
module IntMap = Map.Make(Int)
(** An Ethernet interface. *)
class type interface = object
method my_mac : Macaddr.t
@ -15,16 +30,14 @@ end
class type client_link = object
inherit interface
method other_mac : Macaddr.t
method log_header : string (* For log messages *)
method get_rules : Pf_qubes.Parse_qubes.rule list
method set_rules : string Qubes.DB.KeyMap.t -> unit
method log_header : string (* For log messages *)
method get_rules: Pf_qubes.Parse_qubes.rule list
method set_rules: string Qubes.DB.KeyMap.t -> unit
end
(** An Ethernet header from [src]'s MAC address to [dst]'s with an IPv4 payload.
*)
(** An Ethernet header from [src]'s MAC address to [dst]'s with an IPv4 payload. *)
let eth_header ethertype ~src ~dst =
Ethernet.Packet.make_cstruct
{ Ethernet.Packet.source = src; destination = dst; ethertype }
Ethernet.Packet.make_cstruct { Ethernet.Packet.source = src; destination = dst; ethertype }
let error fmt =
let err s = Failure s in

View File

@ -1,15 +1,61 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
let src = Logs.Src.create "memory_pressure" ~doc:"Memory pressure monitor"
open Lwt
let src = Logs.Src.create "memory_pressure" ~doc:"Memory pressure monitor"
module Log = (val Logs.src_log src : Logs.LOG)
let wordsize_in_bytes = Sys.word_size / 8
let fraction_free stats =
let { Xen_os.Memory.free_words; heap_words; _ } = stats in
float free_words /. float heap_words
let init () = Gc.full_major ()
let meminfo stats =
let { Xen_os.Memory.free_words; heap_words; _ } = stats in
let mem_total = heap_words * wordsize_in_bytes in
let mem_free = free_words * wordsize_in_bytes in
Log.info (fun f -> f "Writing meminfo: free %a / %a (%.2f %%)"
Fmt.bi_byte_size mem_free
Fmt.bi_byte_size mem_total
(fraction_free stats *. 100.0));
Printf.sprintf "MemTotal: %d kB\n\
MemFree: %d kB\n\
Buffers: 0 kB\n\
Cached: 0 kB\n\
SwapTotal: 0 kB\n\
SwapFree: 0 kB\n" (mem_total / 1024) (mem_free / 1024)
let report_mem_usage stats =
Lwt.async (fun () ->
let open Xen_os in
Xs.make () >>= fun xs ->
Xs.immediate xs (fun h ->
Xs.write h "memory/meminfo" (meminfo stats)
)
)
let print_mem_usage =
let rec aux () =
let stats = Xen_os.Memory.quick_stat () in
let { Xen_os.Memory.free_words; heap_words; _ } = stats in
let mem_total = heap_words * wordsize_in_bytes in
let mem_free = free_words * wordsize_in_bytes in
Log.info (fun f -> f "Memory usage: free %a / %a (%.2f %%)"
Fmt.bi_byte_size mem_free
Fmt.bi_byte_size mem_total
(fraction_free stats *. 100.0));
Xen_os.Time.sleep_ns (Duration.of_f 600.0) >>= fun () ->
aux ()
in
aux ()
let init () =
Gc.full_major ();
let stats = Xen_os.Memory.quick_stat () in
print_mem_usage ;
report_mem_usage stats
let status () =
let stats = Xen_os.Memory.quick_stat () in
@ -18,4 +64,7 @@ let status () =
Gc.full_major ();
Xen_os.Memory.trim ();
let stats = Xen_os.Memory.quick_stat () in
if fraction_free stats < 0.6 then `Memory_critical else `Ok)
report_mem_usage stats;
if fraction_free stats < 0.6 then `Memory_critical
else `Ok
)

View File

@ -8,5 +8,5 @@ val status : unit -> [ `Ok | `Memory_critical ]
(** Check the memory situation. If we're running low, do a GC (work-around for
http://caml.inria.fr/mantis/view.php?id=7100 and OCaml GC needing to malloc
extra space to run finalisers). Returns [`Memory_critical] if memory is
still low - caller should take action to reduce memory use. After GC,
updates meminfo in XenStore. *)
still low - caller should take action to reduce memory use.
After GC, updates meminfo in XenStore. *)

109
my_dns.ml
View File

@ -1,81 +1,52 @@
open Lwt.Infix
type +'a io = 'a Lwt.t
type io_addr = Ipaddr.V4.t * int
module Transport (R : Mirage_random.S) (C : Mirage_clock.MCLOCK) (Time : Mirage_time.S) = struct
type +'a io = 'a Lwt.t
type io_addr = Ipaddr.V4.t * int
type stack = Router.t * (src_port:int -> dst:Ipaddr.V4.t -> dst_port:int -> Cstruct.t -> (unit, [ `Msg of string ]) result Lwt.t) * (Udp_packet.t * Cstruct.t) Lwt_mvar.t
type stack =
Dispatcher.t
* (src_port:int ->
dst:Ipaddr.V4.t ->
dst_port:int ->
string ->
(unit, [ `Msg of string ]) result Lwt.t)
* (Udp_packet.t * string) Lwt_mvar.t
type t = {
protocol : Dns.proto ;
nameserver : io_addr ;
stack : stack ;
timeout_ns : int64 ;
}
type context = t
module IM = Map.Make (Int)
let nameservers { protocol ; nameserver ; _ } = protocol, [ nameserver ]
let rng = R.generate ?g:None
let clock = C.elapsed_ns
type t = {
protocol : Dns.proto;
nameserver : io_addr;
stack : stack;
timeout_ns : int64;
mutable requests : string Lwt_condition.t IM.t;
}
let create ?nameservers ~timeout stack =
let protocol, nameserver = match nameservers with
| None | Some (_, []) -> invalid_arg "no nameserver found"
| Some (proto, ns :: _) -> proto, ns
in
{ protocol ; nameserver ; stack ; timeout_ns = timeout }
type context = t
let with_timeout timeout_ns f =
let timeout = Time.sleep_ns timeout_ns >|= fun () -> Error (`Msg "DNS request timeout") in
Lwt.pick [ f ; timeout ]
let nameservers { protocol; nameserver; _ } = (protocol, [ nameserver ])
let rng = Mirage_crypto_rng.generate ?g:None
let clock = Mirage_mtime.elapsed_ns
let connect (t : t) = Lwt.return (Ok t)
let rec read t =
let _, _, answer = t.stack in
Lwt_mvar.take answer >>= fun (_, data) ->
(if String.length data > 2 then
match IM.find_opt (String.get_uint16_be data 0) t.requests with
| Some cond -> Lwt_condition.broadcast cond data
| None -> ());
read t
let send_recv (ctx : context) buf : (Cstruct.t, [> `Msg of string ]) result Lwt.t =
let open Router in
let open My_nat in
let dst, dst_port = ctx.nameserver in
let router, send_udp, answer = ctx.stack in
let src_port = Ports.pick_free_port ~consult:router.ports.nat_udp router.ports.dns_udp in
with_timeout ctx.timeout_ns
((send_udp ~src_port ~dst ~dst_port buf >|= Rresult.R.open_error_msg) >>= function
| Ok () -> (Lwt_mvar.take answer >|= fun (_, dns_response) -> Ok dns_response)
| Error _ as e -> Lwt.return e) >|= fun result ->
router.ports.dns_udp := Ports.remove src_port !(router.ports.dns_udp);
result
let create ?nameservers ~timeout stack =
let protocol, nameserver =
match nameservers with
| None | Some (_, []) -> invalid_arg "no nameserver found"
| Some (proto, ns :: _) -> (proto, ns)
in
let t =
{ protocol; nameserver; stack; timeout_ns = timeout; requests = IM.empty }
in
Lwt.async (fun () -> read t);
t
let close _ = Lwt.return_unit
let with_timeout timeout_ns f =
let timeout =
Mirage_sleep.ns timeout_ns >|= fun () -> Error (`Msg "DNS request timeout")
in
Lwt.pick [ f; timeout ]
let bind = Lwt.bind
let connect (t : t) = Lwt.return (Ok (t.protocol, t))
let lift = Lwt.return
end
let send_recv (ctx : context) buf : (string, [> `Msg of string ]) result Lwt.t =
let dst, dst_port = ctx.nameserver in
let router, send_udp, _ = ctx.stack in
let src_port, evict =
My_nat.free_udp_port router.nat ~src:router.config.our_ip ~dst ~dst_port:53
in
let id = String.get_uint16_be buf 0 in
with_timeout ctx.timeout_ns
(let cond = Lwt_condition.create () in
ctx.requests <- IM.add id cond ctx.requests;
send_udp ~src_port ~dst ~dst_port buf >|= Rresult.R.open_error_msg
>>= function
| Ok () -> Lwt_condition.wait cond >|= fun dns_response -> Ok dns_response
| Error _ as e -> Lwt.return e)
>|= fun result ->
ctx.requests <- IM.remove id ctx.requests;
evict ();
result
let close _ = Lwt.return_unit
let bind = Lwt.bind
let lift = Lwt.return

155
my_nat.ml
View File

@ -1,86 +1,109 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
let src = Logs.Src.create "my-nat" ~doc:"NAT shim"
open Lwt.Infix
let src = Logs.Src.create "my-nat" ~doc:"NAT shim"
module Log = (val Logs.src_log src : Logs.LOG)
type action = [ `NAT | `Redirect of Mirage_nat.endpoint ]
type action = [
| `NAT
| `Redirect of Mirage_nat.endpoint
]
type ports = {
nat_tcp : Ports.t ref;
nat_udp : Ports.t ref;
nat_icmp : Ports.t ref;
dns_udp : Ports.t ref;
}
let empty_ports () =
let nat_tcp = ref Ports.empty in
let nat_udp = ref Ports.empty in
let nat_icmp = ref Ports.empty in
let dns_udp = ref Ports.empty in
{ nat_tcp ; nat_udp ; nat_icmp ; dns_udp }
module Nat = Mirage_nat_lru
module S = Set.Make (struct
type t = int
let compare (a : int) (b : int) = compare a b
end)
type t = { table : Nat.t; mutable udp_dns : S.t; last_resort_port : int }
let pick_port () = 1024 + Random.int (0xffff - 1024)
type t = {
table : Nat.t;
}
let create ~max_entries =
let tcp_size = 7 * max_entries / 8 in
let udp_size = max_entries - tcp_size in
let table = Nat.empty ~tcp_size ~udp_size ~icmp_size:100 in
let last_resort_port = pick_port () in
{ table; udp_dns = S.empty; last_resort_port }
let pick_free_port t proto =
let rec go retries =
if retries = 0 then None
else
let p = 1024 + Random.int (0xffff - 1024) in
match proto with
| `Udp when S.mem p t.udp_dns || p = t.last_resort_port -> go (retries - 1)
| _ -> Some p
in
go 10
let free_udp_port t ~src ~dst ~dst_port =
let rec go retries =
if retries = 0 then (t.last_resort_port, Fun.id)
else
let src_port =
Option.value ~default:t.last_resort_port (pick_free_port t `Udp)
in
if Nat.is_port_free t.table `Udp ~src ~dst ~src_port ~dst_port then
let remove =
if src_port <> t.last_resort_port then (
t.udp_dns <- S.add src_port t.udp_dns;
fun () -> t.udp_dns <- S.remove src_port t.udp_dns)
else Fun.id
in
(src_port, remove)
else go (retries - 1)
in
go 10
let dns_port t port = S.mem port t.udp_dns || port = t.last_resort_port
Nat.empty ~tcp_size ~udp_size ~icmp_size:100 >|= fun table ->
{ table }
let translate t packet =
match Nat.translate t.table packet with
| Error ((`Untranslated | `TTL_exceeded) as e) ->
Log.debug (fun f ->
f "Failed to NAT %a: %a" Nat_packet.pp packet Mirage_nat.pp_error e);
None
Nat.translate t.table packet >|= function
| Error (`Untranslated | `TTL_exceeded as e) ->
Log.debug (fun f -> f "Failed to NAT %a: %a"
Nat_packet.pp packet
Mirage_nat.pp_error e
);
None
| Ok packet -> Some packet
let remove_connections t ip = ignore (Nat.remove_connections t.table ip)
let pick_free_port ~nat_ports ~dns_ports =
Ports.pick_free_port ~consult:dns_ports nat_ports
let add_nat_rule_and_translate t ~xl_host action packet =
let proto =
match packet with
| `IPv4 (_, `TCP _) -> `Tcp
| `IPv4 (_, `UDP _) -> `Udp
| `IPv4 (_, `ICMP _) -> `Icmp
(* just clears the nat ports, dns ports stay as is *)
let reset t ports =
ports.nat_tcp := Ports.empty;
ports.nat_udp := Ports.empty;
ports.nat_icmp := Ports.empty;
Nat.reset t.table
let remove_connections t ports ip =
let freed_ports = Nat.remove_connections t.table ip in
ports.nat_tcp := Ports.diff !(ports.nat_tcp) (Ports.of_list freed_ports.Mirage_nat.tcp);
ports.nat_udp := Ports.diff !(ports.nat_udp) (Ports.of_list freed_ports.Mirage_nat.udp);
ports.nat_icmp := Ports.diff !(ports.nat_icmp) (Ports.of_list freed_ports.Mirage_nat.icmp)
let add_nat_rule_and_translate t ports ~xl_host action packet =
let apply_action xl_port =
Lwt.catch (fun () ->
Nat.add t.table packet (xl_host, xl_port) action
)
(function
| Out_of_memory -> Lwt.return (Error `Out_of_memory)
| x -> Lwt.fail x
)
in
match
Nat.add t.table packet xl_host (fun () -> pick_free_port t proto) action
with
| Error `Overlap -> Error "Too many retries"
| Error `Cannot_NAT -> Error "Cannot NAT this packet"
| Ok () ->
let rec aux ~retries =
let nat_ports, dns_ports =
match packet with
| `IPv4 (_, `TCP _) -> ports.nat_tcp, ref Ports.empty
| `IPv4 (_, `UDP _) -> ports.nat_udp, ports.dns_udp
| `IPv4 (_, `ICMP _) -> ports.nat_icmp, ref Ports.empty
in
let xl_port = pick_free_port ~nat_ports ~dns_ports in
apply_action xl_port >>= function
| Error `Out_of_memory ->
(* Because hash tables resize in big steps, this can happen even if we have a fair
chunk of free memory. *)
Log.warn (fun f -> f "Out_of_memory adding NAT rule. Dropping NAT table...");
reset t ports >>= fun () ->
aux ~retries:(retries - 1)
| Error `Overlap when retries < 0 -> Lwt.return (Error "Too many retries")
| Error `Overlap ->
if retries = 0 then (
Log.warn (fun f -> f "Failed to find a free port; resetting NAT table");
reset t ports >>= fun () ->
aux ~retries:(retries - 1)
) else (
aux ~retries:(retries - 1)
)
| Error `Cannot_NAT ->
Lwt.return (Error "Cannot NAT this packet")
| Ok () ->
Log.debug (fun f -> f "Updated NAT table: %a" Nat.pp_summary t.table);
Option.to_result ~none:"No NAT entry, even after adding one!"
(translate t packet)
translate t packet >|= function
| None -> Error "No NAT entry, even after adding one!"
| Some packet ->
Ok packet
in
aux ~retries:100

View File

@ -3,24 +3,25 @@
(* Abstract over NAT interface (todo: remove this) *)
type ports = private {
nat_tcp : Ports.t ref;
nat_udp : Ports.t ref;
nat_icmp : Ports.t ref;
dns_udp : Ports.t ref;
}
val empty_ports : unit -> ports
type t
type action = [ `NAT | `Redirect of Mirage_nat.endpoint ]
val free_udp_port :
t ->
src:Ipaddr.V4.t ->
dst:Ipaddr.V4.t ->
dst_port:int ->
int * (unit -> unit)
type action = [
| `NAT
| `Redirect of Mirage_nat.endpoint
]
val dns_port : t -> int -> bool
val create : max_entries:int -> t
val remove_connections : t -> Ipaddr.V4.t -> unit
val translate : t -> Nat_packet.t -> Nat_packet.t option
val add_nat_rule_and_translate :
t ->
xl_host:Ipaddr.V4.t ->
action ->
Nat_packet.t ->
(Nat_packet.t, string) result
val create : max_entries:int -> t Lwt.t
val reset : t -> ports -> unit Lwt.t
val remove_connections : t -> ports -> Ipaddr.V4.t -> unit
val translate : t -> Nat_packet.t -> Nat_packet.t option Lwt.t
val add_nat_rule_and_translate : t -> ports ->
xl_host:Ipaddr.V4.t -> action -> Nat_packet.t -> (Nat_packet.t, string) result Lwt.t

View File

@ -8,8 +8,9 @@ type port = int
type host =
[ `Client of client_link | `Firewall | `NetVM | `External of Ipaddr.t ]
type transport_header =
[ `TCP of Tcp.Tcp_packet.t | `UDP of Udp_packet.t | `ICMP of Icmpv4_packet.t ]
type transport_header = [`TCP of Tcp.Tcp_packet.t
|`UDP of Udp_packet.t
|`ICMP of Icmpv4_packet.t]
type ('src, 'dst) t = {
ipv4_header : Ipv4_packet.t;
@ -18,14 +19,13 @@ type ('src, 'dst) t = {
src : 'src;
dst : 'dst;
}
let pp_transport_header f = function
| `ICMP h -> Icmpv4_packet.pp f h
| `TCP h -> Tcp.Tcp_packet.pp f h
| `UDP h -> Udp_packet.pp f h
let pp_host fmt = function
| `Client c -> Ipaddr.V4.pp fmt c#other_ip
| `Client c -> Ipaddr.V4.pp fmt (c#other_ip)
| `Unknown_client ip -> Format.fprintf fmt "unknown-client(%a)" Ipaddr.pp ip
| `NetVM -> Format.pp_print_string fmt "net-vm"
| `External ip -> Format.fprintf fmt "external(%a)" Ipaddr.pp ip
@ -33,28 +33,32 @@ let pp_host fmt = function
let to_mirage_nat_packet t : Nat_packet.t =
match t.transport_header with
| `TCP h -> `IPv4 (t.ipv4_header, `TCP (h, t.transport_payload))
| `UDP h -> `IPv4 (t.ipv4_header, `UDP (h, t.transport_payload))
| `ICMP h -> `IPv4 (t.ipv4_header, `ICMP (h, t.transport_payload))
| `TCP h -> `IPv4 (t.ipv4_header, (`TCP (h, t.transport_payload)))
| `UDP h -> `IPv4 (t.ipv4_header, (`UDP (h, t.transport_payload)))
| `ICMP h -> `IPv4 (t.ipv4_header, (`ICMP (h, t.transport_payload)))
let of_mirage_nat_packet ~src ~dst packet : ('a, 'b) t option =
let (`IPv4 (ipv4_header, ipv4_payload)) = packet in
let transport_header, transport_payload =
match ipv4_payload with
| `TCP (h, p) -> (`TCP h, p)
| `UDP (h, p) -> (`UDP h, p)
| `ICMP (h, p) -> (`ICMP h, p)
let `IPv4 (ipv4_header, ipv4_payload) = packet in
let transport_header, transport_payload = match ipv4_payload with
| `TCP (h, p) -> `TCP h, p
| `UDP (h, p) -> `UDP h, p
| `ICMP (h, p) -> `ICMP h, p
in
Some { ipv4_header; transport_header; transport_payload; src; dst }
Some {
ipv4_header;
transport_header;
transport_payload;
src;
dst;
}
(* possible actions to take for a packet: *)
type action =
[ `Accept (* Send to destination, unmodified. *)
| `NAT
(* Rewrite source field to the firewall's IP, with a fresh source port.
type action = [
| `Accept (* Send to destination, unmodified. *)
| `NAT (* Rewrite source field to the firewall's IP, with a fresh source port.
Also, add translation rules for future traffic in both directions,
between these hosts on these ports, and corresponding ICMP error traffic. *)
| `NAT_to of host * port
(* As for [`NAT], but also rewrite the packet's
| `NAT_to of host * port (* As for [`NAT], but also rewrite the packet's
destination fields so it will be sent to [host:port]. *)
| `Drop of string (* Drop packet for this reason. *) ]
| `Drop of string (* Drop packet for this reason. *)
]

View File

@ -1,13 +1,15 @@
type port = int
type host =
[ `Client of Fw_utils.client_link (** an IP address on the private network *)
| `Firewall (** the firewall's IP on the private network *)
| `NetVM (** the IP of the firewall's default route *)
| `External of Ipaddr.t (** an IP on the public network *) ]
[ `Client of Fw_utils.client_link (** an IP address on the private network *)
| `Firewall (** the firewall's IP on the private network *)
| `NetVM (** the IP of the firewall's default route *)
| `External of Ipaddr.t (** an IP on the public network *)
]
type transport_header =
[ `TCP of Tcp.Tcp_packet.t | `UDP of Udp_packet.t | `ICMP of Icmpv4_packet.t ]
type transport_header = [`TCP of Tcp.Tcp_packet.t
|`UDP of Udp_packet.t
|`ICMP of Icmpv4_packet.t]
type ('src, 'dst) t = {
ipv4_header : Ipv4_packet.t;
@ -18,18 +20,20 @@ type ('src, 'dst) t = {
}
val pp_transport_header : Format.formatter -> transport_header -> unit
val pp_host : Format.formatter -> host -> unit
val to_mirage_nat_packet : ('a, 'b) t -> Nat_packet.t
val of_mirage_nat_packet : src:'a -> dst:'b -> Nat_packet.t -> ('a, 'b) t option
(* possible actions to take for a packet: *)
type action =
[ `Accept (* Send to destination, unmodified. *)
| `NAT
(* Rewrite source field to the firewall's IP, with a fresh source port.
type action = [
| `Accept (* Send to destination, unmodified. *)
| `NAT (* Rewrite source field to the firewall's IP, with a fresh source port.
Also, add translation rules for future traffic in both directions,
between these hosts on these ports, and corresponding ICMP error traffic. *)
| `NAT_to of host * port
(* As for [`NAT], but also rewrite the packet's
| `NAT_to of host * port (* As for [`NAT], but also rewrite the packet's
destination fields so it will be sent to [host:port]. *)
| `Drop of string (* Drop packet for this reason. *) ]
| `Drop of string (* Drop packet for this reason. *)
]

16
ports.ml Normal file
View File

@ -0,0 +1,16 @@
module Set = Set.Make(struct
type t = int
let compare a b = compare a b
end)
include Set
let rec pick_free_port ?(retries = 10) ~consult add_to =
let p = 1024 + Random.int (0xffff - 1024) in
if (mem p !consult || mem p !add_to) && retries <> 0
then pick_free_port ~retries:(retries - 1) ~consult add_to
else
begin
add_to := add p !add_to;
p
end

View File

@ -1 +0,0 @@
0c3c2c0e62a834112c69d7cddc5dd6f70ecb93afa988768fb860ed26e423b1f8 dist/qubes-firewall.xen

View File

@ -1 +0,0 @@
ac049069b35f786fa11b18a2261d7dbecd588301af0363ef6888ec9d924dc989 dist/qubes-firewall.xen

37
router.ml Normal file
View File

@ -0,0 +1,37 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Fw_utils
(* The routing table *)
type t = {
client_eth : Client_eth.t;
nat : My_nat.t;
uplink : interface;
(* NOTE: do not try to make this pure, it relies on mvars / side effects *)
ports : My_nat.ports;
}
let create ~client_eth ~uplink ~nat =
let ports = My_nat.empty_ports () in
{ client_eth; nat; uplink; ports }
let target t buf =
let dst_ip = buf.Ipv4_packet.dst in
match Client_eth.lookup t.client_eth dst_ip with
| Some client_link -> Some (client_link :> interface)
| None -> Some t.uplink
let add_client t = Client_eth.add_client t.client_eth
let remove_client t = Client_eth.remove_client t.client_eth
let classify t ip =
if ip = Ipaddr.V4 t.uplink#my_ip then `Firewall
else if ip = Ipaddr.V4 t.uplink#other_ip then `NetVM
else (Client_eth.classify t.client_eth ip :> Packet.host)
let resolve t = function
| `Firewall -> Ipaddr.V4 t.uplink#my_ip
| `NetVM -> Ipaddr.V4 t.uplink#other_ip
| #Client_eth.host as host -> Client_eth.resolve t.client_eth host

32
router.mli Normal file
View File

@ -0,0 +1,32 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** Routing packets to the right network interface. *)
open Fw_utils
type t = private {
client_eth : Client_eth.t;
nat : My_nat.t;
uplink : interface;
ports : My_nat.ports;
}
val create :
client_eth:Client_eth.t ->
uplink:interface ->
nat:My_nat.t ->
t
(** [create ~client_eth ~uplink ~nat] is a new routing table
that routes packets outside of [client_eth] via [uplink]. *)
val target : t -> Ipv4_packet.t -> interface option
(** [target t packet] is the interface to which [packet] should be routed. *)
val add_client : t -> client_link -> unit Lwt.t
(** [add_client t iface] adds a rule for routing packets addressed to [iface]. *)
val remove_client : t -> client_link -> unit
val classify : t -> Ipaddr.t -> Packet.host
val resolve : t -> Packet.host -> Ipaddr.t

120
rules.ml
View File

@ -8,115 +8,93 @@ open Lwt.Infix
module Q = Pf_qubes.Parse_qubes
let src = Logs.Src.create "rules" ~doc:"Firewall rules"
module Log = (val Logs.src_log src : Logs.LOG)
let dns_port = 53
module Classifier = struct
let matches_port dstports (port : int) =
match dstports with
let matches_port dstports (port : int) = match dstports with
| None -> true
| Some (Q.Range_inclusive (min, max)) -> min <= port && port <= max
let matches_proto rule dns_servers packet =
match (rule.Q.proto, rule.Q.specialtarget) with
let matches_proto rule dns_servers packet = match rule.Q.proto, rule.Q.specialtarget with
| None, None -> true
| None, Some `dns
when List.mem packet.ipv4_header.Ipv4_packet.dst dns_servers -> (
(* specialtarget=dns applies only to the specialtarget destination IPs, and
| None, Some `dns when List.mem packet.ipv4_header.Ipv4_packet.dst dns_servers -> begin
(* specialtarget=dns applies only to the specialtarget destination IPs, and
specialtarget=dns is also implicitly tcp/udp port 53 *)
match packet.transport_header with
match packet.transport_header with
| `TCP header -> header.Tcp.Tcp_packet.dst_port = dns_port
| `UDP header -> header.Udp_packet.dst_port = dns_port
| _ -> false)
(* DNS rules can only match traffic headed to the specialtarget hosts, so any other destination
| _ -> false
end
(* DNS rules can only match traffic headed to the specialtarget hosts, so any other destination
isn't a match for DNS rules *)
| None, Some `dns -> false
| Some rule_proto, _ -> (
match (rule_proto, packet.transport_header) with
| `tcp, `TCP header ->
matches_port rule.Q.dstports header.Tcp.Tcp_packet.dst_port
| `udp, `UDP header ->
matches_port rule.Q.dstports header.Udp_packet.dst_port
| `icmp, `ICMP header -> (
match rule.Q.icmp_type with
| None -> true
| Some rule_icmp_type ->
0
= compare rule_icmp_type
@@ Icmpv4_wire.ty_to_int header.Icmpv4_packet.ty)
| _, _ -> false)
| Some rule_proto, _ -> match rule_proto, packet.transport_header with
| `tcp, `TCP header -> matches_port rule.Q.dstports header.Tcp.Tcp_packet.dst_port
| `udp, `UDP header -> matches_port rule.Q.dstports header.Udp_packet.dst_port
| `icmp, `ICMP header ->
begin
match rule.Q.icmp_type with
| None -> true
| Some rule_icmp_type ->
0 = compare rule_icmp_type @@ Icmpv4_wire.ty_to_int header.Icmpv4_packet.ty
end
| _, _ -> false
let matches_dest dns_client rule packet =
let ip = packet.ipv4_header.Ipv4_packet.dst in
match rule.Q.dst with
| `any -> Lwt.return @@ `Match rule
| `any -> Lwt.return @@ `Match rule
| `hosts subnet ->
Lwt.return
@@
if Ipaddr.Prefix.mem Ipaddr.(V4 ip) subnet then `Match rule
Lwt.return @@ if (Ipaddr.Prefix.mem Ipaddr.(V4 ip) subnet) then `Match rule else `No_match
| `dnsname name ->
Log.debug (fun f -> f "Resolving %a" Domain_name.pp name);
dns_client name >|= function
| Ok (_ttl, found_ips) ->
if Ipaddr.V4.Set.mem ip found_ips
then `Match rule
else `No_match
| `dnsname name -> (
Log.debug (fun f -> f "Resolving %a" Domain_name.pp name);
dns_client name >|= function
| Ok (_ttl, found_ips) ->
if Ipaddr.V4.Set.mem ip found_ips then `Match rule else `No_match
| Error (`Msg m) ->
Log.warn (fun f ->
f "Ignoring rule %a, could not resolve" Q.pp_rule rule);
Log.debug (fun f -> f "%s" m);
`No_match
| Error _ ->
assert
false (* TODO: fix type of dns_client so that this case can go *))
| Error (`Msg m) ->
Log.warn (fun f -> f "Ignoring rule %a, could not resolve" Q.pp_rule rule);
Log.debug (fun f -> f "%s" m);
`No_match
| Error _ -> assert false (* TODO: fix type of dns_client so that this case can go *)
end
let find_first_match dns_client dns_servers packet acc rule =
match acc with
| `No_match ->
if Classifier.matches_proto rule dns_servers packet then
Classifier.matches_dest dns_client rule packet
else Lwt.return `No_match
if Classifier.matches_proto rule dns_servers packet
then Classifier.matches_dest dns_client rule packet
else Lwt.return `No_match
| q -> Lwt.return q
(* Does the packet match our rules? *)
let classify_client_packet dns_client dns_servers
(packet : ([ `Client of Fw_utils.client_link ], _) Packet.t) =
let classify_client_packet dns_client dns_servers (packet : ([`Client of Fw_utils.client_link], _) Packet.t) =
let (`Client client_link) = packet.src in
let rules = client_link#get_rules in
Lwt_list.fold_left_s
(find_first_match dns_client dns_servers packet)
`No_match rules
>|= function
Lwt_list.fold_left_s (find_first_match dns_client dns_servers packet) `No_match rules >|= function
| `No_match -> `Drop "No matching rule; assuming default drop"
| `Match { Q.action = Q.Accept; _ } -> `Accept
| `Match ({ Q.action = Q.Drop; _ } as rule) ->
`Drop
(Format.asprintf "rule number %a explicitly drops this packet" Q.pp_rule
rule)
| `Match {Q.action = Q.Accept; _} -> `Accept
| `Match ({Q.action = Q.Drop; _} as rule) ->
`Drop (Format.asprintf "rule number %a explicitly drops this packet" Q.pp_rule rule)
let translate_accepted_packets dns_client dns_servers packet =
classify_client_packet dns_client dns_servers packet >|= function
| `Accept -> `NAT
| `Drop s -> `Drop s
(** Packets from the private interface that don't match any NAT table entry are
being checked against the fw rules here *)
let from_client dns_client dns_servers
(packet : ([ `Client of Fw_utils.client_link ], _) Packet.t) :
Packet.action Lwt.t =
(** Packets from the private interface that don't match any NAT table entry are being checked against the fw rules here *)
let from_client dns_client dns_servers (packet : ([`Client of Fw_utils.client_link], _) Packet.t) : Packet.action Lwt.t =
match packet with
| { dst = `External _; _ } | { dst = `NetVM; _ } ->
translate_accepted_packets dns_client dns_servers packet
| { dst = `Firewall; _ } ->
Lwt.return @@ `Drop "packet addressed to firewall itself"
| { dst = `Client _; _ } ->
classify_client_packet dns_client dns_servers packet
| { dst = `External _ ; _ } | { dst = `NetVM; _ } -> translate_accepted_packets dns_client dns_servers packet
| { dst = `Firewall ; _ } -> Lwt.return @@ `Drop "packet addressed to firewall itself"
| { dst = `Client _ ; _ } -> classify_client_packet dns_client dns_servers packet
| _ -> Lwt.return @@ `Drop "could not classify packet"
(** Packets from the outside world that don't match any NAT table entry are
being dropped by default *)
let from_netvm (_packet : ([ `NetVM | `External of _ ], _) Packet.t) :
Packet.action Lwt.t =
(** Packets from the outside world that don't match any NAT table entry are being dropped by default *)
let from_netvm (_packet : ([`NetVM | `External of _], _) Packet.t) : Packet.action Lwt.t =
Lwt.return @@ `Drop "drop by default"

View File

@ -2,32 +2,26 @@ open Mirage
let pin = "git+https://github.com/roburio/alcotest.git#mirage"
let packages =
[
package "ethernet";
package "arp";
package "arp-mirage";
package "ipaddr";
package "tcpip" ~sublibs:[ "stack-direct"; "icmpv4"; "ipv4"; "udp"; "tcp" ];
package "mirage-qubes";
package "mirage-qubes-ipv4";
package "dns-client" ~sublibs:[ "mirage" ];
package ~pin "alcotest";
package ~pin "alcotest-mirage";
]
let packages = [
package "ethernet";
package "arp";
package "arp-mirage";
package "ipaddr";
package "tcpip" ~sublibs:["stack-direct"; "icmpv4"; "ipv4"; "udp"; "tcp"];
package "mirage-qubes";
package "mirage-qubes-ipv4";
package "dns-client" ~sublibs:["mirage"];
package ~pin "alcotest";
package ~pin "alcotest-mirage";
]
let client =
foreign ~packages "Unikernel.Client"
@@ random @-> time @-> mclock @-> network @-> qubesdb @-> job
foreign ~packages
"Unikernel.Client" @@ random @-> time @-> mclock @-> network @-> qubesdb @-> job
let db = default_qubesdb
let network = default_network
let () =
let job =
[
client $ default_random $ default_time $ default_monotonic_clock $ network
$ db;
]
in
let job = [ client $ default_random $ default_time $ default_monotonic_clock $ network $ db ] in
register "http-fetch" job

View File

@ -1,8 +1,6 @@
open Lwt.Infix
(* https://www.qubes-os.org/doc/vm-interface/#firewall-rules-in-4x *)
let src = Logs.Src.create "firewall test" ~doc:"Firewalltest"
module Log = (val Logs.src_log src : Logs.LOG)
(* TODO
@ -41,24 +39,18 @@ module Log = (val Logs.src_log src : Logs.LOG)
(* Point-to-point links out of a netvm always have this IP TODO clarify with Marek *)
let netvm = "10.137.0.5"
(* default "nameserver"s, which netvm redirects to whatever its real nameservers are *)
let nameserver_1, nameserver_2 = ("10.139.1.1", "10.139.1.2")
let nameserver_1, nameserver_2 = "10.139.1.1", "10.139.1.2"
module Client
(R : Mirage_crypto_rng_mirage.S)
(Time : Mirage_time.S)
(Clock : Mirage_clock.MCLOCK)
(NET : Mirage_net.S)
(DB : Qubes.S.DB) =
struct
module E = Ethernet.Make (NET)
module A = Arp.Make (E) (Time)
module I = Qubesdb_ipv4.Make (DB) (R) (Clock) (E) (A)
module Icmp = Icmpv4.Make (I)
module U = Udp.Make (I) (R)
module T = Tcp.Flow.Make (I) (Time) (Clock) (R)
module Alcotest = Alcotest_mirage.Make (Clock)
module Client (R: Mirage_random.S) (Time: Mirage_time.S) (Clock : Mirage_clock.MCLOCK) (NET: Mirage_net.S) (DB : Qubes.S.DB) = struct
module E = Ethernet.Make(NET)
module A = Arp.Make(E)(Time)
module I = Qubesdb_ipv4.Make(DB)(R)(Clock)(E)(A)
module Icmp = Icmpv4.Make(I)
module U = Udp.Make(I)(R)
module T = Tcp.Flow.Make(I)(Time)(Clock)(R)
module Alcotest = Alcotest_mirage.Make(Clock)
module Stack = struct
(* A Mirage_stack.V4 implementation which diverts DHCP messages to a DHCP
@ -74,77 +66,67 @@ struct
module IPV4 = I
type t = {
net : NET.t;
eth : E.t;
arp : A.t;
ip : I.t;
icmp : Icmp.t;
udp : U.t;
tcp : T.t;
udp_listeners : (int, U.callback) Hashtbl.t;
tcp_listeners : (int, T.listener) Hashtbl.t;
mutable icmp_listener :
(src:Ipaddr.V4.t -> dst:Ipaddr.V4.t -> Cstruct.t -> unit Lwt.t) option;
net : NET.t ; eth : E.t ; arp : A.t ;
ip : I.t ; icmp : Icmp.t ; udp : U.t ; tcp : T.t ;
udp_listeners : (int, U.callback) Hashtbl.t ;
tcp_listeners : (int, T.listener) Hashtbl.t ;
mutable icmp_listener : (src:Ipaddr.V4.t -> dst:Ipaddr.V4.t -> Cstruct.t -> unit Lwt.t) option ;
}
let ipv4 { ip; _ } = ip
let udpv4 { udp; _ } = udp
let tcpv4 { tcp; _ } = tcp
let icmpv4 { icmp; _ } = icmp
let ipv4 { ip ; _ } = ip
let udpv4 { udp ; _ } = udp
let tcpv4 { tcp ; _ } = tcp
let icmpv4 { icmp ; _ } = icmp
let listener h port = Hashtbl.find_opt h port
let udp_listener h ~dst_port = listener h dst_port
let listen_udpv4 { udp_listeners; _ } ~port cb =
let listen_udpv4 { udp_listeners ; _ } ~port cb =
Hashtbl.replace udp_listeners port cb
let stop_listen_udpv4 { udp_listeners; _ } ~port =
let stop_listen_udpv4 { udp_listeners ; _ } ~port =
Hashtbl.remove udp_listeners port
let listen_tcpv4 ?keepalive { tcp_listeners; _ } ~port cb =
Hashtbl.replace tcp_listeners port { T.process = cb; T.keepalive }
let listen_tcpv4 ?keepalive { tcp_listeners ; _ } ~port cb =
Hashtbl.replace tcp_listeners port { T.process = cb ; T.keepalive }
let stop_listen_tcpv4 { tcp_listeners; _ } ~port =
let stop_listen_tcpv4 { tcp_listeners ; _ } ~port =
Hashtbl.remove tcp_listeners port
let listen_icmp t cb = t.icmp_listener <- cb
let listen t =
let ethif_listener =
E.input ~arpv4:(A.input t.arp)
~ipv4:
(I.input
~tcp:(T.input t.tcp ~listeners:(listener t.tcp_listeners))
~udp:(U.input t.udp ~listeners:(udp_listener t.udp_listeners))
~default:(fun ~proto ~src ~dst buf ->
match proto with
| 1 -> (
match t.icmp_listener with
E.input
~arpv4:(A.input t.arp)
~ipv4:(
I.input
~tcp:(T.input t.tcp ~listeners:(listener t.tcp_listeners))
~udp:(U.input t.udp ~listeners:(udp_listener t.udp_listeners))
~default:(fun ~proto ~src ~dst buf ->
match proto with
| 1 ->
begin match t.icmp_listener with
| None -> Icmp.input t.icmp ~src ~dst buf
| Some cb -> cb ~src ~dst buf)
| _ -> Lwt.return_unit)
t.ip)
| Some cb -> cb ~src ~dst buf
end
| _ -> Lwt.return_unit)
t.ip)
~ipv6:(fun _ -> Lwt.return_unit)
t.eth
in
NET.listen t.net ~header_size:Ethernet_wire.sizeof_ethernet ethif_listener
>>= function
| Error e ->
Logs.warn (fun p -> p "%a" NET.pp_error e);
Lwt.return_unit
Logs.warn (fun p -> p "%a" NET.pp_error e) ;
Lwt.return_unit
| Ok _res -> Lwt.return_unit
let connect net eth arp ip icmp udp tcp =
{
net;
eth;
arp;
ip;
icmp;
udp;
tcp;
udp_listeners = Hashtbl.create 2;
tcp_listeners = Hashtbl.create 2;
icmp_listener = None;
{ net ; eth ; arp ; ip ; icmp ; udp ; tcp ;
udp_listeners = Hashtbl.create 2 ;
tcp_listeners = Hashtbl.create 2 ;
icmp_listener = None ;
}
let disconnect _ =
@ -152,39 +134,31 @@ struct
Lwt.return_unit
end
module Dns = Dns_client_mirage.Make (R) (Time) (Clock) (Stack)
module Dns = Dns_client_mirage.Make(R)(Time)(Clock)(Stack)
let make_ping_packet payload =
let echo_request =
{
Icmpv4_packet.code = 0;
(* constant for echo request/reply *)
ty = Icmpv4_wire.Echo_request;
subheader = Icmpv4_packet.(Id_and_seq (0, 0));
}
in
let echo_request = { Icmpv4_packet.code = 0; (* constant for echo request/reply *)
ty = Icmpv4_wire.Echo_request;
subheader = Icmpv4_packet.(Id_and_seq (0, 0)); } in
Icmpv4_packet.Marshal.make_cstruct echo_request ~payload
let is_ping_reply src server packet =
(0 = Ipaddr.V4.(compare src @@ of_string_exn server))
&& packet.Icmpv4_packet.code = 0
&& packet.Icmpv4_packet.ty = Icmpv4_wire.Echo_reply
&& packet.Icmpv4_packet.subheader = Icmpv4_packet.(Id_and_seq (0, 0))
0 = Ipaddr.V4.(compare src @@ of_string_exn server) &&
packet.Icmpv4_packet.code = 0 &&
packet.Icmpv4_packet.ty = Icmpv4_wire.Echo_reply &&
packet.Icmpv4_packet.subheader = Icmpv4_packet.(Id_and_seq (0, 0))
let ping_denied_listener server resp_received stack =
let icmp_listener ~src ~dst:_ buf =
(* hopefully this is a reply to an ICMP echo request we sent *)
Log.info (fun f ->
f "ping test: ICMP message received from %a: %a" I.pp_ipaddr src
Cstruct.hexdump_pp buf);
Log.info (fun f -> f "ping test: ICMP message received from %a: %a" I.pp_ipaddr src Cstruct.hexdump_pp buf);
match Icmpv4_packet.Unmarshal.of_cstruct buf with
| Error e ->
Log.err (fun f -> f "couldn't parse ICMP packet: %s" e);
Lwt.return_unit
| Error e -> Log.err (fun f -> f "couldn't parse ICMP packet: %s" e);
Lwt.return_unit
| Ok (packet, _payload) ->
Log.info (fun f -> f "ICMP message: %a" Icmpv4_packet.pp packet);
if is_ping_reply src server packet then resp_received := true;
Lwt.return_unit
Log.info (fun f -> f "ICMP message: %a" Icmpv4_packet.pp packet);
if is_ping_reply src server packet then resp_received := true;
Lwt.return_unit
in
Stack.listen_icmp stack (Some icmp_listener)
@ -192,68 +166,49 @@ struct
let resp_received = ref false in
Log.info (fun f -> f "Entering ping test: %s" server);
ping_denied_listener server resp_received stack;
Icmp.write (Stack.icmpv4 stack)
~dst:(Ipaddr.V4.of_string_exn server)
(make_ping_packet (Cstruct.of_string "hi"))
>>= function
| Error e ->
Log.err (fun f -> f "ping test: error sending ping: %a" Icmp.pp_error e);
Lwt.return_unit
Icmp.write (Stack.icmpv4 stack) ~dst:(Ipaddr.V4.of_string_exn server) (make_ping_packet (Cstruct.of_string "hi")) >>= function
| Error e -> Log.err (fun f -> f "ping test: error sending ping: %a" Icmp.pp_error e); Lwt.return_unit
| Ok () ->
Log.info (fun f -> f "ping test: sent ping to %s" server);
Time.sleep_ns 2_000_000_000L >>= fun () ->
if !resp_received then
Log.err (fun f ->
f "ping test failed: server %s got a response, block expected :("
server)
else Log.err (fun f -> f "ping test passed: successfully blocked :)");
Stack.listen_icmp stack None;
Lwt.return_unit
Log.info (fun f -> f "ping test: sent ping to %s" server);
Time.sleep_ns 2_000_000_000L >>= fun () ->
(if !resp_received then
Log.err (fun f -> f "ping test failed: server %s got a response, block expected :(" server)
else
Log.err (fun f -> f "ping test passed: successfully blocked :)")
);
Stack.listen_icmp stack None;
Lwt.return_unit
let icmp_error_type stack () =
let resp_correct = ref false in
let echo_server = Ipaddr.V4.of_string_exn netvm in
let icmp_callback ~src ~dst:_ buf =
(if Ipaddr.V4.compare src echo_server = 0 then
(* TODO: check that packet is error packet *)
match Icmpv4_packet.Unmarshal.of_cstruct buf with
| Error e -> Log.err (fun f -> f "Error parsing icmp packet %s" e)
| Ok (packet, _) ->
if Ipaddr.V4.compare src echo_server = 0 then begin
(* TODO: check that packet is error packet *)
match Icmpv4_packet.Unmarshal.of_cstruct buf with
| Error e -> Log.err (fun f -> f "Error parsing icmp packet %s" e)
| Ok (packet, _) ->
(* TODO don't hardcode the numbers, make a datatype *)
if
packet.Icmpv4_packet.code
= 10 (* unreachable, admin prohibited *)
if packet.Icmpv4_packet.code = 10 (* unreachable, admin prohibited *)
then resp_correct := true
else
Log.debug (fun f ->
f "Unrelated icmp packet %a" Icmpv4_packet.pp packet));
else Log.debug (fun f -> f "Unrelated icmp packet %a" Icmpv4_packet.pp packet)
end;
Lwt.return_unit
in
let content = Cstruct.of_string "important data" in
Stack.listen_icmp stack (Some icmp_callback);
U.write ~src_port:1337 ~dst:echo_server ~dst_port:1338 (Stack.udpv4 stack)
content
>>= function
| Ok () ->
(* .. listener: test with accept rule, if we get reply we're good *)
Time.sleep_ns 1_000_000_000L >>= fun () ->
if !resp_correct then
Log.info (fun m -> m "UDP fetch test to port %d succeeded :)" 1338)
else
Log.err (fun f ->
f
"UDP fetch test to port %d: failed. :( correct response not \
received"
1338);
Stack.listen_icmp stack None;
Lwt.return_unit
U.write ~src_port:1337 ~dst:echo_server ~dst_port:1338 (Stack.udpv4 stack) content >>= function
| Ok () -> (* .. listener: test with accept rule, if we get reply we're good *)
Time.sleep_ns 1_000_000_000L >>= fun () ->
if !resp_correct
then Log.info (fun m -> m "UDP fetch test to port %d succeeded :)" 1338)
else Log.err (fun f -> f "UDP fetch test to port %d: failed. :( correct response not received" 1338);
Stack.listen_icmp stack None;
Lwt.return_unit
| Error e ->
Log.err (fun f ->
f
"UDP fetch test to port %d failed: :( couldn't write the packet: \
%a"
1338 U.pp_error e);
Lwt.return_unit
Log.err (fun f -> f "UDP fetch test to port %d failed: :( couldn't write the packet: %a"
1338 U.pp_error e);
Lwt.return_unit
let tcp_connect msg server port tcp () =
Log.info (fun f -> f "Entering tcp connect test: %s:%d" server port);
@ -261,141 +216,98 @@ struct
let msg' = Printf.sprintf "TCP connect test %s to %s:%d" msg server port in
T.create_connection tcp (ip, port) >>= function
| Ok flow ->
Log.info (fun f -> f "%s passed :)" msg');
T.close flow
| Error e ->
Log.err (fun f ->
f "%s failed: Connection failed (%a) :(" msg' T.pp_error e);
Lwt.return_unit
Log.info (fun f -> f "%s passed :)" msg');
T.close flow
| Error e -> Log.err (fun f -> f "%s failed: Connection failed (%a) :(" msg' T.pp_error e);
Lwt.return_unit
let tcp_connect_denied msg server port tcp () =
let ip = Ipaddr.V4.of_string_exn server in
let msg' =
Printf.sprintf "TCP connect denied test %s to %s:%d" msg server port
let msg' = Printf.sprintf "TCP connect denied test %s to %s:%d" msg server port in
let connect = (T.create_connection tcp (ip, port) >>= function
| Ok flow ->
Log.err (fun f -> f "%s failed: Connection should be denied, but was not. :(" msg');
T.close flow
| Error e -> Log.info (fun f -> f "%s passed (error text: %a) :)" msg' T.pp_error e);
Lwt.return_unit)
in
let connect =
T.create_connection tcp (ip, port) >>= function
| Ok flow ->
Log.err (fun f ->
f "%s failed: Connection should be denied, but was not. :(" msg');
T.close flow
| Error e ->
Log.info (fun f ->
f "%s passed (error text: %a) :)" msg' T.pp_error e);
Lwt.return_unit
in
let timeout =
let timeout = (
Time.sleep_ns 1_000_000_000L >>= fun () ->
Log.info (fun f -> f "%s passed :)" msg');
Lwt.return_unit
Lwt.return_unit)
in
Lwt.pick [ connect; timeout ]
Lwt.pick [ connect ; timeout ]
let udp_fetch ~src_port ~echo_server_port stack () =
Log.info (fun f ->
f "Entering udp fetch test: %d -> %s:%d" src_port netvm echo_server_port);
Log.info (fun f -> f "Entering udp fetch test: %d -> %s:%d"
src_port netvm echo_server_port);
let resp_correct = ref false in
let echo_server = Ipaddr.V4.of_string_exn netvm in
let content = Cstruct.of_string "important data" in
let udp_listener : U.callback =
fun ~src ~dst:_ ~src_port buf ->
Log.debug (fun f ->
f "listen_udpv4 function invoked for packet: %a" Cstruct.hexdump_pp
buf);
if 0 = Ipaddr.V4.compare echo_server src && src_port = echo_server_port
then (
match Cstruct.equal buf content with
| true ->
(* yay *)
Log.info (fun f ->
f "UDP fetch test to port %d: passed :)" echo_server_port);
let udp_listener : U.callback = (fun ~src ~dst:_ ~src_port buf ->
Log.debug (fun f -> f "listen_udpv4 function invoked for packet: %a" Cstruct.hexdump_pp buf);
if ((0 = Ipaddr.V4.compare echo_server src) && src_port = echo_server_port) then
match Cstruct.equal buf content with
| true -> (* yay *)
Log.info (fun f -> f "UDP fetch test to port %d: passed :)" echo_server_port);
resp_correct := true;
Lwt.return_unit
| false ->
(* oh no *)
Log.err (fun f ->
f
"UDP fetch test to port %d: failed. :( Packet corrupted; \
expected %a but got %a"
echo_server_port Cstruct.hexdump_pp content Cstruct.hexdump_pp
buf);
Lwt.return_unit)
else (
(* disregard this packet *)
Log.debug (fun f ->
f
"packet is not from the echo server or has the wrong source port \
(%d but we wanted %d)"
src_port echo_server_port);
(* don't cancel the listener, since we want to keep listening *)
Lwt.return_unit)
| false -> (* oh no *)
Log.err (fun f -> f "UDP fetch test to port %d: failed. :( Packet corrupted; expected %a but got %a"
echo_server_port Cstruct.hexdump_pp content Cstruct.hexdump_pp buf);
Lwt.return_unit
else
begin
(* disregard this packet *)
Log.debug (fun f -> f "packet is not from the echo server or has the wrong source port (%d but we wanted %d)"
src_port echo_server_port);
(* don't cancel the listener, since we want to keep listening *)
Lwt.return_unit
end
)
in
Stack.listen_udpv4 stack ~port:src_port udp_listener;
U.write ~src_port ~dst:echo_server ~dst_port:echo_server_port
(Stack.udpv4 stack) content
>>= function
| Ok () ->
(* .. listener: test with accept rule, if we get reply we're good *)
Time.sleep_ns 1_000_000_000L >>= fun () ->
Stack.stop_listen_udpv4 stack ~port:src_port;
if !resp_correct then Lwt.return_unit
else (
Log.err (fun f ->
f
"UDP fetch test to port %d: failed. :( correct response not \
received"
echo_server_port);
Lwt.return_unit)
| Error e ->
Log.err (fun f ->
f
"UDP fetch test to port %d failed: :( couldn't write the packet: \
%a"
echo_server_port U.pp_error e);
U.write ~src_port ~dst:echo_server ~dst_port:echo_server_port (Stack.udpv4 stack) content >>= function
| Ok () -> (* .. listener: test with accept rule, if we get reply we're good *)
Time.sleep_ns 1_000_000_000L >>= fun () ->
Stack.stop_listen_udpv4 stack ~port:src_port;
if !resp_correct then Lwt.return_unit else begin
Log.err (fun f -> f "UDP fetch test to port %d: failed. :( correct response not received" echo_server_port);
Lwt.return_unit
end
| Error e ->
Log.err (fun f -> f "UDP fetch test to port %d failed: :( couldn't write the packet: %a"
echo_server_port U.pp_error e);
Lwt.return_unit
let dns_expect_failure ~nameserver ~hostname stack () =
let lookup = Domain_name.(of_string_exn hostname |> host_exn) in
let nameserver' = (`UDP, (Ipaddr.V4.of_string_exn nameserver, 53)) in
let nameserver' = `UDP, (Ipaddr.V4.of_string_exn nameserver, 53) in
let dns = Dns.create ~nameserver:nameserver' stack in
Dns.gethostbyname dns lookup >>= function
| Error (`Msg s) when String.compare s "Truncated UDP response" <> 0 ->
Log.debug (fun f ->
f "DNS test to %s failed as expected: %s" nameserver s);
Log.info (fun f ->
f "DNS traffic to %s correctly blocked :)" nameserver);
Lwt.return_unit
| Error (`Msg s) when String.compare s "Truncated UDP response" <> 0 -> Log.debug (fun f -> f "DNS test to %s failed as expected: %s"
nameserver s);
Log.info (fun f -> f "DNS traffic to %s correctly blocked :)" nameserver);
Lwt.return_unit
| Error (`Msg s) ->
Log.debug (fun f ->
f "DNS test to %s failed unexpectedly (truncated response): %s :("
nameserver s);
Lwt.return_unit
| Ok addr ->
Log.err (fun f ->
f "DNS test to %s should have been blocked, but looked up %s:%a"
nameserver hostname Ipaddr.V4.pp addr);
Lwt.return_unit
Log.debug (fun f -> f "DNS test to %s failed unexpectedly (truncated response): %s :("
nameserver s);
Lwt.return_unit
| Ok addr -> Log.err (fun f -> f "DNS test to %s should have been blocked, but looked up %s:%a" nameserver hostname Ipaddr.V4.pp addr);
Lwt.return_unit
let dns_then_tcp_denied server stack () =
let parsed_server = Domain_name.(of_string_exn server |> host_exn) in
(* ask dns about server *)
Log.debug (fun f ->
f "going to make a dns thing using nameserver %s" nameserver_1);
let dns =
Dns.create
~nameserver:(`UDP, (Ipaddr.V4.of_string_exn nameserver_1, 53))
stack
in
Log.debug (fun f -> f "going to make a dns thing using nameserver %s" nameserver_1);
let dns = Dns.create ~nameserver:(`UDP, ((Ipaddr.V4.of_string_exn nameserver_1), 53)) stack in
Log.debug (fun f -> f "OK, going to look up %s now" server);
Dns.gethostbyname dns parsed_server >>= function
| Error (`Msg s) ->
Log.err (fun f -> f "couldn't look up ip for %s: %s" server s);
Lwt.return_unit
| Error (`Msg s) -> Log.err (fun f -> f "couldn't look up ip for %s: %s" server s); Lwt.return_unit
| Ok addr ->
Log.debug (fun f ->
f "looked up ip for %s: %a" server Ipaddr.V4.pp addr);
Log.err (fun f -> f "Do more stuff here!!!! :(");
Lwt.return_unit
Log.debug (fun f -> f "looked up ip for %s: %a" server Ipaddr.V4.pp addr);
Log.err (fun f -> f "Do more stuff here!!!! :(");
Lwt.return_unit
let start _random _time _clock network db =
E.connect network >>= fun ethernet ->
@ -404,64 +316,42 @@ struct
Icmp.connect ipv4 >>= fun icmp ->
U.connect ipv4 >>= fun udp ->
T.connect ipv4 >>= fun tcp ->
let stack = Stack.connect network ethernet arp ipv4 icmp udp tcp in
let stack = Stack.connect network ethernet arp ipv4 icmp udp tcp in
Lwt.async (fun () -> Stack.listen stack);
(* put this first because tcp_connect_denied tests also generate icmp messages *)
let general_tests : unit Alcotest.test =
( "firewall tests",
[
( "UDP fetch",
`Quick,
udp_fetch ~src_port:9090 ~echo_server_port:1235 stack );
("Ping expect failure", `Quick, ping_expect_failure "8.8.8.8" stack);
(* TODO: ping_expect_success to the netvm, for which we have an icmptype rule in update-firewall.sh *)
("ICMP error type", `Quick, icmp_error_type stack);
] )
in
let general_tests : unit Alcotest.test = ("firewall tests", [
("UDP fetch", `Quick, udp_fetch ~src_port:9090 ~echo_server_port:1235 stack);
("Ping expect failure", `Quick, ping_expect_failure "8.8.8.8" stack );
(* TODO: ping_expect_success to the netvm, for which we have an icmptype rule in update-firewall.sh *)
("ICMP error type", `Quick, icmp_error_type stack)
] ) in
Alcotest.run ~and_exit:false "name" [ general_tests ] >>= fun () ->
let tcp_tests : unit Alcotest.test =
( "tcp tests",
[
(* this test fails on 4.0R3
let tcp_tests : unit Alcotest.test = ("tcp tests", [
(* this test fails on 4.0R3
("TCP connect", `Quick, tcp_connect "when trying specialtarget" nameserver_1 53 tcp); *)
("TCP connect", `Quick, tcp_connect_denied "" netvm 53 tcp);
( "TCP connect",
`Quick,
tcp_connect_denied "when trying below range" netvm 6667 tcp );
( "TCP connect",
`Quick,
tcp_connect "when trying lower bound in range" netvm 6668 tcp );
( "TCP connect",
`Quick,
tcp_connect "when trying upper bound in range" netvm 6670 tcp );
( "TCP connect",
`Quick,
tcp_connect_denied "when trying above range" netvm 6671 tcp );
("TCP connect", `Quick, tcp_connect_denied "" netvm 8082 tcp);
] )
in
("TCP connect", `Quick, tcp_connect_denied "" netvm 53 tcp);
("TCP connect", `Quick, tcp_connect_denied "when trying below range" netvm 6667 tcp);
("TCP connect", `Quick, tcp_connect "when trying lower bound in range" netvm 6668 tcp);
("TCP connect", `Quick, tcp_connect "when trying upper bound in range" netvm 6670 tcp);
("TCP connect", `Quick, tcp_connect_denied "when trying above range" netvm 6671 tcp);
("TCP connect", `Quick, tcp_connect_denied "" netvm 8082 tcp);
] ) in
(* replace the udp-related listeners with the right one for tcp *)
Alcotest.run "name" [ tcp_tests ] >>= fun () ->
(* use the stack abstraction only after the other tests have run, since it's not friendly with outside use of its modules *)
let stack_tests =
( "stack tests",
[
( "DNS expect failure",
`Quick,
dns_expect_failure ~nameserver:"8.8.8.8" ~hostname:"mirage.io" stack
);
(* the test below won't work on @linse's internet,
let stack_tests = "stack tests", [
("DNS expect failure", `Quick, dns_expect_failure ~nameserver:"8.8.8.8" ~hostname:"mirage.io" stack);
(* the test below won't work on @linse's internet,
* because the nameserver there doesn't answer on TCP port 53,
* only UDP port 53. Dns_mirage_client.ml disregards our request
* to use UDP and uses TCP anyway, so this request can never work there. *)
(* If we can figure out a way to have this test unikernel do a UDP lookup with minimal pain,
(* If we can figure out a way to have this test unikernel do a UDP lookup with minimal pain,
* we should re-enable this test. *)
( "DNS lookup + TCP connect",
`Quick,
dns_then_tcp_denied "google.com" stack );
] )
in
("DNS lookup + TCP connect", `Quick, dns_then_tcp_denied "google.com" stack);
] in
Alcotest.run "name" [ stack_tests ]
end

View File

@ -3,124 +3,76 @@
open Lwt
open Qubes
open Cmdliner
let src = Logs.Src.create "unikernel" ~doc:"Main unikernel code"
module Log = (val Logs.src_log src : Logs.LOG)
let nat_table_size =
let doc =
Arg.info ~doc:"The number of NAT entries to allocate." [ "nat-table-size" ]
in
Mirage_runtime.register_arg Arg.(value & opt int 5_000 doc)
module Main (R : Mirage_random.S)(Clock : Mirage_clock.MCLOCK)(Time : Mirage_time.S) = struct
module Uplink = Uplink.Make(R)(Clock)(Time)
module Dns_transport = My_dns.Transport(R)(Clock)(Time)
module Dns_client = Dns_client.Make(Dns_transport)
let ipv4 =
let doc = Arg.info ~doc:"Manual IP setting." [ "ipv4" ] in
Mirage_runtime.register_arg Arg.(value & opt string "0.0.0.0" doc)
let ipv4_gw =
let doc = Arg.info ~doc:"Manual Gateway IP setting." [ "ipv4-gw" ] in
Mirage_runtime.register_arg Arg.(value & opt string "0.0.0.0" doc)
let ipv4_dns =
let doc = Arg.info ~doc:"Manual DNS IP setting." [ "ipv4-dns" ] in
Mirage_runtime.register_arg Arg.(value & opt string "10.139.1.1" doc)
let ipv4_dns2 =
let doc = Arg.info ~doc:"Manual Second DNS IP setting." [ "ipv4-dns2" ] in
Mirage_runtime.register_arg Arg.(value & opt string "10.139.1.2" doc)
module Dns_client = Dns_client.Make (My_dns)
(* Set up networking and listen for incoming packets. *)
let network dns_client dns_responses dns_servers qubesDB router =
(* Report success *)
Dao.set_iptables_error qubesDB "" >>= fun () ->
(* Handle packets from both networks *)
Lwt.choose
[
Dispatcher.wait_clients Mirage_mtime.elapsed_ns dns_client dns_servers
qubesDB router;
Dispatcher.uplink_wait_update qubesDB router;
Dispatcher.uplink_listen Mirage_mtime.elapsed_ns dns_responses router;
(* Set up networking and listen for incoming packets. *)
let network dns_client dns_responses dns_servers uplink qubesDB router =
(* Report success *)
Dao.set_iptables_error qubesDB "" >>= fun () ->
(* Handle packets from both networks *)
Lwt.choose [
Client_net.listen Clock.elapsed_ns dns_client dns_servers qubesDB router;
Uplink.listen uplink Clock.elapsed_ns dns_responses router
]
(* Main unikernel entry point (called from auto-generated main.ml). *)
let start () =
let open Lwt.Syntax in
let start_time = Mirage_mtime.elapsed_ns () in
(* Start qrexec agent and QubesDB agent in parallel *)
let* qrexec = RExec.connect ~domid:0 () in
let agent_listener = RExec.listen qrexec Command.handler in
let* qubesDB = DB.connect ~domid:0 () in
let startup_time =
let ( - ) = Int64.sub in
let time_in_ns = Mirage_mtime.elapsed_ns () - start_time in
Int64.to_float time_in_ns /. 1e9
in
Log.info (fun f ->
f "QubesDB and qrexec agents connected in %.3f s" startup_time);
(* Watch for shutdown requests from Qubes *)
let shutdown_rq =
Xen_os.Lifecycle.await_shutdown_request () >>= fun (`Poweroff | `Reboot) ->
Lwt.return_unit
in
(* Set up networking *)
let nat = My_nat.create ~max_entries:(nat_table_size ()) in
(* Main unikernel entry point (called from auto-generated main.ml). *)
let start _random _clock _time =
let start_time = Clock.elapsed_ns () in
(* Start qrexec agent and QubesDB agent in parallel *)
let qrexec = RExec.connect ~domid:0 () in
let qubesDB = DB.connect ~domid:0 () in
let netvm_ip = Ipaddr.V4.of_string_exn (ipv4_gw ()) in
let our_ip = Ipaddr.V4.of_string_exn (ipv4 ()) in
let dns = Ipaddr.V4.of_string_exn (ipv4_dns ()) in
let dns2 = Ipaddr.V4.of_string_exn (ipv4_dns2 ()) in
(* Wait for clients to connect *)
qrexec >>= fun qrexec ->
let agent_listener = RExec.listen qrexec Command.handler in
qubesDB >>= fun qubesDB ->
let startup_time =
let (-) = Int64.sub in
let time_in_ns = Clock.elapsed_ns () - start_time in
Int64.to_float time_in_ns /. 1e9
in
Log.info (fun f -> f "QubesDB and qrexec agents connected in %.3f s" startup_time);
(* Watch for shutdown requests from Qubes *)
let shutdown_rq =
Xen_os.Lifecycle.await_shutdown_request () >>= fun (`Poweroff | `Reboot) ->
Lwt.return_unit in
(* Set up networking *)
let max_entries = Key_gen.nat_table_size () in
My_nat.create ~max_entries >>= fun nat ->
let zero_ip = Ipaddr.V4.any in
(* Read network configuration from QubesDB *)
Dao.read_network_config qubesDB >>= fun config ->
let network_config =
if netvm_ip = zero_ip && our_ip = zero_ip then (
(* Read network configuration from QubesDB *)
Dao.read_network_config qubesDB
>>= fun config ->
if config.netvm_ip = zero_ip || config.our_ip = zero_ip then
Log.info (fun f ->
f
"We currently have no netvm nor command line for setting it up, \
aborting...");
assert (config.netvm_ip <> zero_ip && config.our_ip <> zero_ip);
Lwt.return config)
else
let config : Dao.network_config =
{ from_cmdline = true; netvm_ip; our_ip; dns; dns2 }
in
Lwt.return config
in
network_config >>= fun config ->
(* We now must have a valid netvm IP address and our IP address or crash *)
Dao.print_network_config config;
Uplink.connect config >>= fun uplink ->
(* Set up client-side networking *)
let client_eth = Client_eth.create
~client_gw:config.Dao.clients_our_ip in
(* Set up routing between networks and hosts *)
let router = Router.create
~client_eth
~uplink:(Uplink.interface uplink)
~nat
in
(* Set up client-side networking *)
let* clients = Client_eth.create config in
let send_dns_query = Uplink.send_dns_client_query uplink in
let dns_mvar = Lwt_mvar.create_empty () in
let nameservers = `Udp, [ config.Dao.dns, 53 ; config.Dao.dns2, 53 ] in
let dns_client = Dns_client.create ~nameservers (router, send_dns_query, dns_mvar) in
(* Set up routing between networks and hosts *)
let router = Dispatcher.create ~config ~clients ~nat ~uplink:None in
let dns_servers = [ config.Dao.dns ; config.Dao.dns2 ] in
let net_listener = network (Dns_client.getaddrinfo dns_client Dns.Rr_map.A) dns_mvar dns_servers uplink qubesDB router in
let send_dns_query = Dispatcher.send_dns_client_query router in
let dns_mvar = Lwt_mvar.create_empty () in
let nameservers = (`Udp, [ (config.Dao.dns, 53); (config.Dao.dns2, 53) ]) in
let dns_client =
Dns_client.create ~nameservers (router, send_dns_query, dns_mvar)
in
let dns_servers = [ config.Dao.dns; config.Dao.dns2 ] in
let net_listener =
network
(Dns_client.getaddrinfo dns_client Dns.Rr_map.A)
dns_mvar dns_servers qubesDB router
in
(* Report memory usage to XenStore *)
Memory_pressure.init ();
(* Run until something fails or we get a shutdown request. *)
Lwt.choose [ agent_listener; net_listener; shutdown_rq ] >>= fun () ->
(* Give the console daemon time to show any final log messages. *)
Mirage_sleep.ns (1.0 *. 1e9 |> Int64.of_float)
(* Report memory usage to XenStore *)
Memory_pressure.init ();
(* Run until something fails or we get a shutdown request. *)
Lwt.choose [agent_listener; net_listener; shutdown_rq] >>= fun () ->
(* Give the console daemon time to show any final log messages. *)
Time.sleep_ns (1.0 *. 1e9 |> Int64.of_float)
end

97
uplink.ml Normal file
View File

@ -0,0 +1,97 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
open Lwt.Infix
open Fw_utils
module Eth = Ethernet.Make(Netif)
let src = Logs.Src.create "uplink" ~doc:"Network connection to NetVM"
module Log = (val Logs.src_log src : Logs.LOG)
module Make (R:Mirage_random.S) (Clock : Mirage_clock.MCLOCK) (Time : Mirage_time.S) = struct
module Arp = Arp.Make(Eth)(Time)
module I = Static_ipv4.Make(R)(Clock)(Eth)(Arp)
module U = Udp.Make(I)(R)
type t = {
net : Netif.t;
eth : Eth.t;
arp : Arp.t;
interface : interface;
mutable fragments : Fragments.Cache.t;
ip : I.t;
udp: U.t;
}
class netvm_iface eth mac ~my_ip ~other_ip : interface = object
val queue = FrameQ.create (Ipaddr.V4.to_string other_ip)
method my_mac = Eth.mac eth
method my_ip = my_ip
method other_ip = other_ip
method writev ethertype fillfn =
FrameQ.send queue (fun () ->
mac >>= fun dst ->
Eth.write eth dst ethertype fillfn >|= or_raise "Write to uplink" Eth.pp_error
)
end
let send_dns_client_query t ~src_port ~dst ~dst_port buf =
U.write ~src_port ~dst ~dst_port t.udp buf >|= function
| Error s -> Log.err (fun f -> f "error sending udp packet: %a" U.pp_error s); Error (`Msg "failure")
| Ok () -> Ok ()
let listen t get_ts dns_responses router =
let handle_packet ip_header ip_packet =
let open Udp_packet in
Log.debug (fun f -> f "received ipv4 packet from %a on uplink" Ipaddr.V4.pp ip_header.Ipv4_packet.src);
match ip_packet with
| `UDP (header, packet) when Ports.mem header.dst_port !(router.Router.ports.My_nat.dns_udp) ->
Log.debug (fun f -> f "found a DNS packet whose dst_port (%d) was in the list of dns_client ports" header.dst_port);
Lwt_mvar.put dns_responses (header, packet)
| _ ->
Firewall.ipv4_from_netvm router (`IPv4 (ip_header, ip_packet))
in
Netif.listen t.net ~header_size:Ethernet.Packet.sizeof_ethernet (fun frame ->
(* Handle one Ethernet frame from NetVM *)
Eth.input t.eth
~arpv4:(Arp.input t.arp)
~ipv4:(fun ip ->
let cache, r =
Nat_packet.of_ipv4_packet t.fragments ~now:(get_ts ()) ip
in
t.fragments <- cache;
match r with
| Error e ->
Log.warn (fun f -> f "Ignored unknown IPv4 message from uplink: %a" Nat_packet.pp_error e);
Lwt.return ()
| Ok None -> Lwt.return_unit
| Ok (Some (`IPv4 (header, packet))) -> handle_packet header packet
)
~ipv6:(fun _ip -> Lwt.return_unit)
frame
) >|= or_raise "Uplink listen loop" Netif.pp_error
let interface t = t.interface
let connect config =
let my_ip = config.Dao.uplink_our_ip in
let gateway = config.Dao.uplink_netvm_ip in
Netif.connect "0" >>= fun net ->
Eth.connect net >>= fun eth ->
Arp.connect eth >>= fun arp ->
Arp.add_ip arp my_ip >>= fun () ->
let cidr = Ipaddr.V4.Prefix.make 0 my_ip in
I.connect ~cidr ~gateway eth arp >>= fun ip ->
U.connect ip >>= fun udp ->
let netvm_mac =
Arp.query arp gateway
>|= or_raise "Getting MAC of our NetVM" Arp.pp_error in
let interface = new netvm_iface eth netvm_mac
~my_ip
~other_ip:config.Dao.uplink_netvm_ip in
let fragments = Fragments.Cache.empty (256 * 1024) in
Lwt.return { net; eth; arp; interface ; fragments ; ip ; udp }
end

22
uplink.mli Normal file
View File

@ -0,0 +1,22 @@
(* Copyright (C) 2015, Thomas Leonard <thomas.leonard@unikernel.com>
See the README file for details. *)
(** The link from us to NetVM (and, through that, to the outside world). *)
open Fw_utils
[@@@ocaml.warning "-67"]
module Make (R: Mirage_random.S)(Clock : Mirage_clock.MCLOCK)(Time : Mirage_time.S) : sig
type t
val connect : Dao.network_config -> t Lwt.t
(** Connect to our NetVM (gateway). *)
val interface : t -> interface
(** The network interface to NetVM. *)
val listen : t -> (unit -> int64) -> (Udp_packet.t * Cstruct.t) Lwt_mvar.t -> Router.t -> unit Lwt.t
(** Handle incoming frames from NetVM. *)
val send_dns_client_query: t -> src_port:int-> dst:Ipaddr.V4.t -> dst_port:int -> Cstruct.t -> (unit, [`Msg of string]) result Lwt.t
end