blob: 3f88d6f7dae0e5c9c39425160557ef4a1e967da0 [file] [log] [blame]
// Copyright 2020 The Monogon Project Authors.
//
// SPDX-License-Identifier: Apache-2.0
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package kubernetes
import (
"context"
"fmt"
"net"
"os"
"path/filepath"
"regexp"
"github.com/container-storage-interface/spec/lib/go/csi"
"github.com/golang/protobuf/ptypes/wrappers"
"golang.org/x/sys/unix"
"google.golang.org/grpc"
"google.golang.org/grpc/codes"
"google.golang.org/grpc/status"
pluginregistration "k8s.io/kubelet/pkg/apis/pluginregistration/v1"
"source.monogon.dev/metropolis/node/core/localstorage"
"source.monogon.dev/metropolis/pkg/fsquota"
"source.monogon.dev/metropolis/pkg/logtree"
"source.monogon.dev/metropolis/pkg/supervisor"
)
// Derived from K8s spec for acceptable names, but shortened to 130 characters to avoid issues with
// maximum path length. We don't provision longer names so this applies only if you manually create
// a volume with a name of more than 130 characters.
var acceptableNames = regexp.MustCompile("^[a-z][a-bz0-9-.]{0,128}[a-z0-9]$")
const volumeDir = "volumes"
type csiPluginServer struct {
KubeletDirectory *localstorage.DataKubernetesKubeletDirectory
VolumesDirectory *localstorage.DataVolumesDirectory
logger logtree.LeveledLogger
}
func (s *csiPluginServer) Run(ctx context.Context) error {
s.logger = supervisor.Logger(ctx)
pluginListener, err := net.ListenUnix("unix", &net.UnixAddr{Name: s.KubeletDirectory.Plugins.VFS.FullPath(), Net: "unix"})
if err != nil {
return fmt.Errorf("failed to listen on CSI socket: %w", err)
}
pluginListener.SetUnlinkOnClose(true)
pluginServer := grpc.NewServer()
csi.RegisterIdentityServer(pluginServer, s)
csi.RegisterNodeServer(pluginServer, s)
// Enable graceful shutdown since we don't have long-running RPCs and most of them shouldn't and can't be
// cancelled anyways.
if err := supervisor.Run(ctx, "csi-node", supervisor.GRPCServer(pluginServer, pluginListener, true)); err != nil {
return err
}
registrationListener, err := net.ListenUnix("unix", &net.UnixAddr{Name: s.KubeletDirectory.PluginsRegistry.VFSReg.FullPath(), Net: "unix"})
if err != nil {
return fmt.Errorf("failed to listen on CSI registration socket: %w", err)
}
registrationListener.SetUnlinkOnClose(true)
registrationServer := grpc.NewServer()
pluginregistration.RegisterRegistrationServer(registrationServer, s)
if err := supervisor.Run(ctx, "registration", supervisor.GRPCServer(registrationServer, registrationListener, true)); err != nil {
return err
}
supervisor.Signal(ctx, supervisor.SignalHealthy)
supervisor.Signal(ctx, supervisor.SignalDone)
return nil
}
func (*csiPluginServer) NodeStageVolume(ctx context.Context, req *csi.NodeStageVolumeRequest) (*csi.NodeStageVolumeResponse, error) {
return nil, status.Errorf(codes.Unimplemented, "method NodeStageVolume not supported")
}
func (*csiPluginServer) NodeUnstageVolume(ctx context.Context, req *csi.NodeUnstageVolumeRequest) (*csi.NodeUnstageVolumeResponse, error) {
return nil, status.Errorf(codes.Unimplemented, "method NodeUnstageVolume not supported")
}
func (s *csiPluginServer) NodePublishVolume(ctx context.Context, req *csi.NodePublishVolumeRequest) (*csi.NodePublishVolumeResponse, error) {
if !acceptableNames.MatchString(req.VolumeId) {
return nil, status.Error(codes.InvalidArgument, "invalid characters in volume id")
}
// TODO(q3k): move this logic to localstorage?
volumePath := filepath.Join(s.VolumesDirectory.FullPath(), req.VolumeId)
switch req.VolumeCapability.AccessMode.Mode {
case csi.VolumeCapability_AccessMode_SINGLE_NODE_WRITER:
case csi.VolumeCapability_AccessMode_SINGLE_NODE_READER_ONLY:
default:
return nil, status.Error(codes.InvalidArgument, "unsupported access mode")
}
switch req.VolumeCapability.AccessType.(type) {
case *csi.VolumeCapability_Mount:
default:
return nil, status.Error(codes.InvalidArgument, "unsupported access type")
}
err := unix.Mount(volumePath, req.TargetPath, "", unix.MS_BIND, "")
switch {
case err == unix.ENOENT:
return nil, status.Error(codes.NotFound, "volume not found")
case err != nil:
return nil, status.Errorf(codes.Unavailable, "failed to bind-mount volume: %v", err)
}
if req.Readonly {
err := unix.Mount(volumePath, req.TargetPath, "", unix.MS_BIND|unix.MS_REMOUNT|unix.MS_RDONLY, "")
if err != nil {
_ = unix.Unmount(req.TargetPath, 0) // Best-effort
return nil, status.Errorf(codes.Unavailable, "failed to remount volume: %v", err)
}
}
return &csi.NodePublishVolumeResponse{}, nil
}
func (*csiPluginServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpublishVolumeRequest) (*csi.NodeUnpublishVolumeResponse, error) {
if err := unix.Unmount(req.TargetPath, 0); err != nil {
return nil, status.Errorf(codes.Unavailable, "failed to unmount volume: %v", err)
}
return &csi.NodeUnpublishVolumeResponse{}, nil
}
func (*csiPluginServer) NodeGetVolumeStats(ctx context.Context, req *csi.NodeGetVolumeStatsRequest) (*csi.NodeGetVolumeStatsResponse, error) {
quota, err := fsquota.GetQuota(req.VolumePath)
if os.IsNotExist(err) {
return nil, status.Error(codes.NotFound, "volume does not exist at this path")
} else if err != nil {
return nil, status.Errorf(codes.Unavailable, "failed to get quota: %v", err)
}
return &csi.NodeGetVolumeStatsResponse{
Usage: []*csi.VolumeUsage{
{
Total: int64(quota.Bytes),
Unit: csi.VolumeUsage_BYTES,
Used: int64(quota.BytesUsed),
Available: int64(quota.Bytes - quota.BytesUsed),
},
{
Total: int64(quota.Inodes),
Unit: csi.VolumeUsage_INODES,
Used: int64(quota.InodesUsed),
Available: int64(quota.Inodes - quota.InodesUsed),
},
},
}, nil
}
func (*csiPluginServer) NodeExpandVolume(ctx context.Context, req *csi.NodeExpandVolumeRequest) (*csi.NodeExpandVolumeResponse, error) {
if req.CapacityRange.LimitBytes <= 0 {
return nil, status.Error(codes.InvalidArgument, "invalid expanded volume size: at or below zero bytes")
}
if err := fsquota.SetQuota(req.VolumePath, uint64(req.CapacityRange.LimitBytes), 0); err != nil {
return nil, status.Errorf(codes.Unavailable, "failed to update quota: %v", err)
}
return &csi.NodeExpandVolumeResponse{CapacityBytes: req.CapacityRange.LimitBytes}, nil
}
func rpcCapability(cap csi.NodeServiceCapability_RPC_Type) *csi.NodeServiceCapability {
return &csi.NodeServiceCapability{
Type: &csi.NodeServiceCapability_Rpc{
Rpc: &csi.NodeServiceCapability_RPC{Type: cap},
},
}
}
func (*csiPluginServer) NodeGetCapabilities(ctx context.Context, req *csi.NodeGetCapabilitiesRequest) (*csi.NodeGetCapabilitiesResponse, error) {
return &csi.NodeGetCapabilitiesResponse{
Capabilities: []*csi.NodeServiceCapability{
rpcCapability(csi.NodeServiceCapability_RPC_EXPAND_VOLUME),
rpcCapability(csi.NodeServiceCapability_RPC_GET_VOLUME_STATS),
},
}, nil
}
func (*csiPluginServer) NodeGetInfo(ctx context.Context, req *csi.NodeGetInfoRequest) (*csi.NodeGetInfoResponse, error) {
hostname, err := os.Hostname()
if err != nil {
return nil, status.Errorf(codes.Unavailable, "failed to get node identity: %v", err)
}
return &csi.NodeGetInfoResponse{
NodeId: hostname,
}, nil
}
// CSI Identity endpoints
func (*csiPluginServer) GetPluginInfo(ctx context.Context, req *csi.GetPluginInfoRequest) (*csi.GetPluginInfoResponse, error) {
return &csi.GetPluginInfoResponse{
Name: "dev.monogon.metropolis.vfs",
VendorVersion: "0.0.1", // TODO(lorenz): Maybe stamp?
}, nil
}
func (*csiPluginServer) GetPluginCapabilities(ctx context.Context, req *csi.GetPluginCapabilitiesRequest) (*csi.GetPluginCapabilitiesResponse, error) {
return &csi.GetPluginCapabilitiesResponse{
Capabilities: []*csi.PluginCapability{
{
Type: &csi.PluginCapability_VolumeExpansion_{
VolumeExpansion: &csi.PluginCapability_VolumeExpansion{
Type: csi.PluginCapability_VolumeExpansion_ONLINE,
},
},
},
},
}, nil
}
func (s *csiPluginServer) Probe(ctx context.Context, req *csi.ProbeRequest) (*csi.ProbeResponse, error) {
return &csi.ProbeResponse{Ready: &wrappers.BoolValue{Value: true}}, nil
}
// Registration endpoints
func (s *csiPluginServer) GetInfo(ctx context.Context, req *pluginregistration.InfoRequest) (*pluginregistration.PluginInfo, error) {
return &pluginregistration.PluginInfo{
Type: pluginregistration.CSIPlugin,
Name: "dev.monogon.metropolis.vfs",
Endpoint: s.KubeletDirectory.Plugins.VFS.FullPath(),
SupportedVersions: []string{"1.2"}, // Keep in sync with container-storage-interface/spec package version
}, nil
}
func (s *csiPluginServer) NotifyRegistrationStatus(ctx context.Context, req *pluginregistration.RegistrationStatus) (*pluginregistration.RegistrationStatusResponse, error) {
if req.Error != "" {
s.logger.Warningf("Kubelet failed registering CSI plugin: %v", req.Error)
}
return &pluginregistration.RegistrationStatusResponse{}, nil
}