This will be important for host-based networking in Spectrum.
---
...upport-setting-guest-MAC-from-tap-fd.patch | 294 ++++++++++++++++++
.../linux/chromium-os/crosvm/default.nix | 1 +
2 files changed, 295 insertions(+)
create mode 100644 pkgs/os-specific/linux/chromium-os/crosvm/0001-crosvm-support-setting-guest-MAC-from-tap-fd.patch
diff --git a/pkgs/os-specific/linux/chromium-os/crosvm/0001-crosvm-support-setting-guest-MAC-from-tap-fd.patch b/pkgs/os-specific/linux/chromium-os/crosvm/0001-crosvm-support-setting-guest-MAC-from-tap-fd.patch
new file mode 100644
index 00000000000..df0f16ee23a
--- /dev/null
+++ b/pkgs/os-specific/linux/chromium-os/crosvm/0001-crosvm-support-setting-guest-MAC-from-tap-fd.patch
@@ -0,0 +1,294 @@
+From 2db1db4e42e87f05e414384a0c09be340e81d94d Mon Sep 17 00:00:00 2001
+From: Alyssa Ross
+Date: Sun, 27 Sep 2020 15:34:02 +0000
+Subject: [PATCH] crosvm: support setting guest MAC from tap-fd
+
+This adds a mac= option to crosvm's --tap-fd option. The virtio-net
+driver in the guest will read the desired MAC from virtio
+configuration space.
+
+See the documentation for VIRTIO_NET_F_MAC in the Virtio spec[1].
+
+[1]: https://docs.oasis-open.org/virtio/virtio/v1.1/virtio-v1.1.html
+
+Thanks-to: Puck Meerburg
+
+---
+ devices/src/virtio/net.rs | 31 ++++++++++++++++---
+ src/crosvm.rs | 8 +++--
+ src/linux.rs | 20 +++++++-----
+ src/main.rs | 64 ++++++++++++++++++++++++++++++---------
+ 4 files changed, 96 insertions(+), 27 deletions(-)
+
+diff --git a/devices/src/virtio/net.rs b/devices/src/virtio/net.rs
+index 44a39abd..fe71371f 100644
+--- a/devices/src/virtio/net.rs
++++ b/devices/src/virtio/net.rs
+@@ -22,7 +22,9 @@ use virtio_sys::virtio_net::{
+ };
+ use virtio_sys::{vhost, virtio_net};
+
+-use super::{DescriptorError, Interrupt, Queue, Reader, VirtioDevice, Writer, TYPE_NET};
++use super::{
++ copy_config, DescriptorError, Interrupt, Queue, Reader, VirtioDevice, Writer, TYPE_NET,
++};
+
+ const QUEUE_SIZE: u16 = 256;
+ const NUM_QUEUES: usize = 3;
+@@ -373,7 +375,13 @@ where
+ }
+ }
+
++#[derive(Default)]
++pub struct NetOptions {
++ pub guest_mac: Option,
++}
++
+ pub struct Net {
++ config: Vec<u8>,
+ workers_kill_evt: Option<EventFd>,
+ kill_evt: EventFd,
+ worker_thread: Option>,
+@@ -392,6 +400,7 @@ where
+ ip_addr: Ipv4Addr,
+ netmask: Ipv4Addr,
+ mac_addr: MacAddress,
++ options: NetOptions,
+ ) -> Result {
+ let tap: T = T::new(true).map_err(NetError::TapOpen)?;
+ tap.set_ip_addr(ip_addr).map_err(NetError::TapSetIp)?;
+@@ -401,18 +410,18 @@ where
+
+ tap.enable().map_err(NetError::TapEnable)?;
+
+- Net::from(tap)
++ Net::with_tap(tap, options)
+ }
+
+ /// Creates a new virtio network device from a tap device that has already been
+ /// configured.
+- pub fn from(tap: T) -> Result {
++ pub fn with_tap(tap: T, options: NetOptions) -> Result {
+ // This would also validate a tap created by Self::new(), but that's a good thing as it
+ // would ensure that any changes in the creation procedure are matched in the validation.
+ // Plus we still need to set the offload and vnet_hdr_size values.
+ validate_and_configure_tap(&tap)?;
+
+- let avail_features = 1 << virtio_net::VIRTIO_NET_F_GUEST_CSUM
++ let mut avail_features = 1 << virtio_net::VIRTIO_NET_F_GUEST_CSUM
+ | 1 << virtio_net::VIRTIO_NET_F_CSUM
+ | 1 << virtio_net::VIRTIO_NET_F_CTRL_VQ
+ | 1 << virtio_net::VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
+@@ -422,8 +431,18 @@ where
+ | 1 << virtio_net::VIRTIO_NET_F_HOST_UFO
+ | 1 << vhost::VIRTIO_F_VERSION_1;
+
++ if options.guest_mac.is_some() {
++ avail_features |= 1 << virtio_net::VIRTIO_NET_F_MAC;
++ }
++
++ let config = options
++ .guest_mac
++ .map(|mac| mac.octets().to_vec())
++ .unwrap_or_default();
++
+ let kill_evt = EventFd::new().map_err(NetError::CreateKillEventFd)?;
+ Ok(Net {
++ config,
+ workers_kill_evt: Some(kill_evt.try_clone().map_err(NetError::CloneKillEventFd)?),
+ kill_evt,
+ worker_thread: None,
+@@ -545,6 +564,10 @@ where
+ }
+ }
+
++ fn read_config(&self, offset: u64, data: &mut [u8]) {
++ copy_config(data, 0, self.config.as_slice(), offset);
++ }
++
+ fn activate(
+ &mut self,
+ mem: GuestMemory,
+diff --git a/src/crosvm.rs b/src/crosvm.rs
+index 81344c32..e69f2dfc 100644
+--- a/src/crosvm.rs
++++ b/src/crosvm.rs
+@@ -157,6 +157,10 @@ impl Default for SharedDir {
+ }
+ }
+
++pub struct TapFdOptions {
++ pub mac: Option,
++}
++
+ /// Aggregate of all configurable options for a running VM.
+ pub struct Config {
+ pub vcpu_count: Option<u32>,
+@@ -177,7 +181,7 @@ pub struct Config {
+ pub netmask: Optionnet::Ipv4Addr,
+ pub mac_address: Option,
+ pub vhost_net: bool,
+- pub tap_fd: Vec<RawFd>,
++ pub tap_fd: BTreeMap,
+ pub cid: Option<u64>,
+ pub wayland_socket_paths: BTreeMap,
+ pub wayland_dmabuf: bool,
+@@ -224,7 +228,7 @@ impl Default for Config {
+ netmask: None,
+ mac_address: None,
+ vhost_net: false,
+- tap_fd: Vec::new(),
++ tap_fd: BTreeMap::new(),
+ cid: None,
+ #[cfg(feature = "gpu")]
+ gpu_parameters: None,
+diff --git a/src/linux.rs b/src/linux.rs
+index 3370c1e1..f7f78ad2 100644
+--- a/src/linux.rs
++++ b/src/linux.rs
+@@ -60,7 +60,9 @@ use vm_control::{
+ VmMemoryRequest, VmMemoryResponse, VmRunMode,
+ };
+
+-use crate::{Config, DiskOption, Executable, SharedDir, SharedDirKind, TouchDeviceOption};
++use crate::{
++ Config, DiskOption, Executable, SharedDir, SharedDirKind, TapFdOptions, TouchDeviceOption,
++};
+ use arch::{self, LinuxArch, RunnableLinuxVm, VirtioDeviceStub, VmComponents, VmImage};
+
+ #[cfg(any(target_arch = "arm", target_arch = "aarch64"))]
+@@ -586,14 +588,18 @@ fn create_balloon_device(cfg: &Config, socket: BalloonControlResponseSocket) ->
+ })
+ }
+
+-fn create_tap_net_device(cfg: &Config, tap_fd: RawFd) -> DeviceResult {
++fn create_tap_net_device(cfg: &Config, tap_fd: RawFd, options: &TapFdOptions) -> DeviceResult {
+ // Safe because we ensure that we get a unique handle to the fd.
+ let tap = unsafe {
+ Tap::from_raw_fd(validate_raw_fd(tap_fd).map_err(Error::ValidateRawFd)?)
+ .map_err(Error::CreateTapDevice)?
+ };
+
+- let dev = virtio::Net::from(tap).map_err(Error::NetDeviceNew)?;
++ let net_opts = virtio::NetOptions {
++ guest_mac: options.mac,
++ };
++
++ let dev = virtio::Net::with_tap(tap, net_opts).map_err(Error::NetDeviceNew)?;
+
+ Ok(VirtioDeviceStub {
+ dev: Box::new(dev),
+@@ -614,8 +620,8 @@ fn create_net_device(
+ .map_err(Error::VhostNetDeviceNew)?;
+ Box::new(dev) as Box<dyn VirtioDevice>
+ } else {
+- let dev =
+- virtio::Net::<Tap>::new(host_ip, netmask, mac_address).map_err(Error::NetDeviceNew)?;
++ let dev = virtio::Net::<Tap>::new(host_ip, netmask, mac_address, Default::default())
++ .map_err(Error::NetDeviceNew)?;
+ Box::new(dev) as Box<dyn VirtioDevice>
+ };
+
+@@ -1006,8 +1012,8 @@ fn create_virtio_devices(
+ devs.push(create_balloon_device(cfg, balloon_device_socket)?);
+
+ // We checked above that if the IP is defined, then the netmask is, too.
+- for tap_fd in &cfg.tap_fd {
+- devs.push(create_tap_net_device(cfg, *tap_fd)?);
++ for (tap_fd, options) in &cfg.tap_fd {
++ devs.push(create_tap_net_device(cfg, *tap_fd, options)?);
+ }
+
+ if let (Some(host_ip), Some(netmask), Some(mac_address)) =
+diff --git a/src/main.rs b/src/main.rs
+index 3afca8e0..053af465 100644
+--- a/src/main.rs
++++ b/src/main.rs
+@@ -21,7 +21,8 @@ use arch::Pstore;
+ use audio_streams::StreamEffect;
+ use crosvm::{
+ argument::{self, print_help, set_arguments, Argument},
+- linux, BindMount, Config, DiskOption, Executable, GidMap, SharedDir, TouchDeviceOption,
++ linux, BindMount, Config, DiskOption, Executable, GidMap, SharedDir, TapFdOptions,
++ TouchDeviceOption,
+ };
+ #[cfg(feature = "gpu")]
+ use devices::virtio::gpu::{GpuMode, GpuParameters};
+@@ -1041,17 +1042,52 @@ fn set_argument(cfg: &mut Config, name: &str, value: Option<&str>) -> argument::
+ }
+ "vhost-net" => cfg.vhost_net = true,
+ "tap-fd" => {
+- cfg.tap_fd.push(
+- value
+- .unwrap()
+- .parse()
+- .map_err(|_| argument::Error::InvalidValue {
+- value: value.unwrap().to_owned(),
+- expected: String::from(
+- "this value for `tap-fd` must be an unsigned integer",
+- ),
+- })?,
+- );
++ let mut components = value.unwrap().split(',');
++
++ let fd: RawFd = components
++ .next()
++ .and_then(|x| x.parse().ok())
++ .ok_or_else(|| argument::Error::InvalidValue {
++ value: value.unwrap().to_owned(),
++ expected: String::from("this value for `tap-fd` must be an unsigned integer"),
++ })?;
++
++ let mut mac = None;
++ for c in components {
++ let mut kv = c.splitn(2, '=');
++ let (kind, value) = match (kv.next(), kv.next()) {
++ (Some(kind), Some(value)) => (kind, value),
++ _ => {
++ return Err(argument::Error::InvalidValue {
++ value: c.to_owned(),
++ expected: String::from("option must be of the form `kind=value`"),
++ })
++ }
++ };
++ match kind {
++ "mac" => {
++ mac = Some(value.parse().map_err(|_| argument::Error::InvalidValue {
++ value: value.to_owned(),
++ expected: String::from(
++ "`mac` needs to be in the form \"XX:XX:XX:XX:XX:XX\"",
++ ),
++ })?)
++ }
++ _ => {
++ return Err(argument::Error::InvalidValue {
++ value: kind.to_owned(),
++ expected: String::from("unrecognized option"),
++ })
++ }
++ }
++ }
++ if cfg.tap_fd.contains_key(&fd) {
++ return Err(argument::Error::TooManyArguments(format!(
++ "TAP FD already used: '{}'",
++ name
++ )));
++ }
++ cfg.tap_fd.insert(fd, TapFdOptions { mac });
+ }
+ #[cfg(feature = "gpu")]
+ "gpu" => {
+@@ -1295,8 +1331,8 @@ writeback=BOOL - Indicates whether the VM can use writeback caching (default: fa
+ Argument::value("plugin-gid-map-file", "PATH", "Path to the file listing supplemental GIDs that should be mapped in plugin jail. Can be given more than once."),
+ Argument::flag("vhost-net", "Use vhost for networking."),
+ Argument::value("tap-fd",
+- "fd",
+- "File descriptor for configured tap device. A different virtual network card will be added each time this argument is given."),
++ "FD[,mac=MAC]",
++ "File descriptor for configured tap device. A different virtual network card will be added each time this argument is given. MAC is the MAC address that will be set in the guest."),
+ #[cfg(feature = "gpu")]
+ Argument::flag_or_value("gpu",
+ "[width=INT,height=INT]",
+--
+2.27.0
+
diff --git a/pkgs/os-specific/linux/chromium-os/crosvm/default.nix b/pkgs/os-specific/linux/chromium-os/crosvm/default.nix
index d64dc316772..d54c050d308 100644
--- a/pkgs/os-specific/linux/chromium-os/crosvm/default.nix
+++ b/pkgs/os-specific/linux/chromium-os/crosvm/default.nix
@@ -39,6 +39,7 @@ in
patches = [
./default-seccomp-policy-dir.diff
+ ./0001-crosvm-support-setting-guest-MAC-from-tap-fd.patch
];
cargoSha256 = "0wzqn2n4vyv3bk39079yg1zbnriagi5xns928bzdqmq9djdcj21i";
--
2.30.0
