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path: root/pkg/rootlessport/rootlessport_linux.go
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Diffstat (limited to 'pkg/rootlessport/rootlessport_linux.go')
-rw-r--r--pkg/rootlessport/rootlessport_linux.go347
1 files changed, 2 insertions, 345 deletions
diff --git a/pkg/rootlessport/rootlessport_linux.go b/pkg/rootlessport/rootlessport_linux.go
index 37fb7ce79..7b9e5bbfa 100644
--- a/pkg/rootlessport/rootlessport_linux.go
+++ b/pkg/rootlessport/rootlessport_linux.go
@@ -12,33 +12,12 @@
package rootlessport
import (
- "context"
- "encoding/json"
- "fmt"
- "io"
- "io/ioutil"
- "net"
- "os"
- "os/exec"
- "path/filepath"
-
- "github.com/containernetworking/plugins/pkg/ns"
"github.com/containers/podman/v3/libpod/network/types"
- "github.com/containers/storage/pkg/reexec"
- "github.com/pkg/errors"
- rkport "github.com/rootless-containers/rootlesskit/pkg/port"
- rkbuiltin "github.com/rootless-containers/rootlesskit/pkg/port/builtin"
- rkportutil "github.com/rootless-containers/rootlesskit/pkg/port/portutil"
- "github.com/sirupsen/logrus"
- "golang.org/x/sys/unix"
)
const (
- // ReexecKey is the reexec key for the parent process.
- ReexecKey = "containers-rootlessport"
- // reexecChildKey is used internally for the second reexec
- reexecChildKey = "containers-rootlessport-child"
- reexecChildEnvOpaque = "_CONTAINERS_ROOTLESSPORT_CHILD_OPAQUE"
+ // BinaryName is the binary name for the parent process.
+ BinaryName = "rootlessport"
)
// Config needs to be provided to the process via stdin as a JSON string.
@@ -53,325 +32,3 @@ type Config struct {
ContainerID string
RootlessCNI bool
}
-
-func init() {
- reexec.Register(ReexecKey, func() {
- if err := parent(); err != nil {
- fmt.Println(err)
- os.Exit(1)
- }
- })
- reexec.Register(reexecChildKey, func() {
- if err := child(); err != nil {
- fmt.Println(err)
- os.Exit(1)
- }
- })
-}
-
-func loadConfig(r io.Reader) (*Config, io.ReadCloser, io.WriteCloser, error) {
- stdin, err := ioutil.ReadAll(r)
- if err != nil {
- return nil, nil, nil, err
- }
- var cfg Config
- if err := json.Unmarshal(stdin, &cfg); err != nil {
- return nil, nil, nil, err
- }
- if cfg.NetNSPath == "" {
- return nil, nil, nil, errors.New("missing NetNSPath")
- }
- if cfg.ExitFD <= 0 {
- return nil, nil, nil, errors.New("missing ExitFD")
- }
- exitFile := os.NewFile(uintptr(cfg.ExitFD), "exitfile")
- if exitFile == nil {
- return nil, nil, nil, errors.New("invalid ExitFD")
- }
- if cfg.ReadyFD <= 0 {
- return nil, nil, nil, errors.New("missing ReadyFD")
- }
- readyFile := os.NewFile(uintptr(cfg.ReadyFD), "readyfile")
- if readyFile == nil {
- return nil, nil, nil, errors.New("invalid ReadyFD")
- }
- return &cfg, exitFile, readyFile, nil
-}
-
-func parent() error {
- // load config from stdin
- cfg, exitR, readyW, err := loadConfig(os.Stdin)
- if err != nil {
- return err
- }
-
- socketDir := filepath.Join(cfg.TmpDir, "rp")
- err = os.MkdirAll(socketDir, 0700)
- if err != nil {
- return err
- }
-
- // create the parent driver
- stateDir, err := ioutil.TempDir(cfg.TmpDir, "rootlessport")
- if err != nil {
- return err
- }
- defer os.RemoveAll(stateDir)
- driver, err := rkbuiltin.NewParentDriver(&logrusWriter{prefix: "parent: "}, stateDir)
- if err != nil {
- return err
- }
- initComplete := make(chan struct{})
- quit := make(chan struct{})
- errCh := make(chan error)
- // start the parent driver. initComplete will be closed when the child connected to the parent.
- logrus.Infof("Starting parent driver")
- go func() {
- driverErr := driver.RunParentDriver(initComplete, quit, nil)
- if driverErr != nil {
- logrus.WithError(driverErr).Warn("Parent driver exited")
- }
- errCh <- driverErr
- close(errCh)
- }()
- opaque := driver.OpaqueForChild()
- logrus.Infof("Opaque=%+v", opaque)
- opaqueJSON, err := json.Marshal(opaque)
- if err != nil {
- return err
- }
- childQuitR, childQuitW, err := os.Pipe()
- if err != nil {
- return err
- }
- defer func() {
- // stop the child
- logrus.Info("Stopping child driver")
- if err := childQuitW.Close(); err != nil {
- logrus.WithError(err).Warn("Unable to close childQuitW")
- }
- }()
-
- // reexec the child process in the child netns
- cmd := exec.Command("/proc/self/exe")
- cmd.Args = []string{reexecChildKey}
- cmd.Stdin = childQuitR
- cmd.Stdout = &logrusWriter{prefix: "child"}
- cmd.Stderr = cmd.Stdout
- cmd.Env = append(os.Environ(), reexecChildEnvOpaque+"="+string(opaqueJSON))
- childNS, err := ns.GetNS(cfg.NetNSPath)
- if err != nil {
- return err
- }
- if err := childNS.Do(func(_ ns.NetNS) error {
- logrus.Infof("Starting child driver in child netns (%q %v)", cmd.Path, cmd.Args)
- return cmd.Start()
- }); err != nil {
- return err
- }
-
- childErrCh := make(chan error)
- go func() {
- err := cmd.Wait()
- childErrCh <- err
- close(childErrCh)
- }()
-
- defer func() {
- if err := unix.Kill(cmd.Process.Pid, unix.SIGTERM); err != nil {
- logrus.WithError(err).Warn("Kill child process")
- }
- }()
-
- logrus.Info("Waiting for initComplete")
- // wait for the child to connect to the parent
-outer:
- for {
- select {
- case <-initComplete:
- logrus.Infof("initComplete is closed; parent and child established the communication channel")
- break outer
- case err := <-childErrCh:
- if err != nil {
- return err
- }
- case err := <-errCh:
- if err != nil {
- return err
- }
- }
- }
-
- defer func() {
- logrus.Info("Stopping parent driver")
- quit <- struct{}{}
- if err := <-errCh; err != nil {
- logrus.WithError(err).Warn("Parent driver returned error on exit")
- }
- }()
-
- // let parent expose ports
- logrus.Infof("Exposing ports %v", cfg.Mappings)
- if err := exposePorts(driver, cfg.Mappings, cfg.ChildIP); err != nil {
- return err
- }
-
- // we only need to have a socket to reload ports when we run under rootless cni
- if cfg.RootlessCNI {
- socketfile := filepath.Join(socketDir, cfg.ContainerID)
- // make sure to remove the file if it exists to prevent EADDRINUSE
- _ = os.Remove(socketfile)
- // workaround to bypass the 108 char socket path limit
- // open the fd and use the path to the fd as bind argument
- fd, err := unix.Open(socketDir, unix.O_PATH, 0)
- if err != nil {
- return err
- }
- socket, err := net.ListenUnix("unixpacket", &net.UnixAddr{Name: fmt.Sprintf("/proc/self/fd/%d/%s", fd, cfg.ContainerID), Net: "unixpacket"})
- if err != nil {
- return err
- }
- err = unix.Close(fd)
- // remove the socket file on exit
- defer os.Remove(socketfile)
- if err != nil {
- logrus.Warnf("Failed to close the socketDir fd: %v", err)
- }
- defer socket.Close()
- go serve(socket, driver)
- }
-
- logrus.Info("Ready")
-
- // https://github.com/containers/podman/issues/11248
- // Copy /dev/null to stdout and stderr to prevent SIGPIPE errors
- if f, err := os.OpenFile("/dev/null", os.O_WRONLY, 0755); err == nil {
- unix.Dup2(int(f.Fd()), 1) // nolint:errcheck
- unix.Dup2(int(f.Fd()), 2) // nolint:errcheck
- f.Close()
- }
- // write and close ReadyFD (convention is same as slirp4netns --ready-fd)
- if _, err := readyW.Write([]byte("1")); err != nil {
- return err
- }
- if err := readyW.Close(); err != nil {
- return err
- }
-
- // wait for ExitFD to be closed
- logrus.Info("Waiting for exitfd to be closed")
- if _, err := ioutil.ReadAll(exitR); err != nil {
- return err
- }
- return nil
-}
-
-func serve(listener net.Listener, pm rkport.Manager) {
- for {
- conn, err := listener.Accept()
- if err != nil {
- // we cannot log this error, stderr is already closed
- continue
- }
- ctx := context.TODO()
- err = handler(ctx, conn, pm)
- if err != nil {
- conn.Write([]byte(err.Error()))
- } else {
- conn.Write([]byte("OK"))
- }
- conn.Close()
- }
-}
-
-func handler(ctx context.Context, conn io.Reader, pm rkport.Manager) error {
- var childIP string
- dec := json.NewDecoder(conn)
- err := dec.Decode(&childIP)
- if err != nil {
- return errors.Wrap(err, "rootless port failed to decode ports")
- }
- portStatus, err := pm.ListPorts(ctx)
- if err != nil {
- return errors.Wrap(err, "rootless port failed to list ports")
- }
- for _, status := range portStatus {
- err = pm.RemovePort(ctx, status.ID)
- if err != nil {
- return errors.Wrap(err, "rootless port failed to remove port")
- }
- }
- // add the ports with the new child IP
- for _, status := range portStatus {
- // set the new child IP
- status.Spec.ChildIP = childIP
- _, err = pm.AddPort(ctx, status.Spec)
- if err != nil {
- return errors.Wrap(err, "rootless port failed to add port")
- }
- }
- return nil
-}
-
-func exposePorts(pm rkport.Manager, portMappings []types.OCICNIPortMapping, childIP string) error {
- ctx := context.TODO()
- for _, i := range portMappings {
- hostIP := i.HostIP
- if hostIP == "" {
- hostIP = "0.0.0.0"
- }
- spec := rkport.Spec{
- Proto: i.Protocol,
- ParentIP: hostIP,
- ParentPort: int(i.HostPort),
- ChildPort: int(i.ContainerPort),
- ChildIP: childIP,
- }
- if err := rkportutil.ValidatePortSpec(spec, nil); err != nil {
- return err
- }
- if _, err := pm.AddPort(ctx, spec); err != nil {
- return err
- }
- }
- return nil
-}
-
-func child() error {
- // load the config from the parent
- var opaque map[string]string
- if err := json.Unmarshal([]byte(os.Getenv(reexecChildEnvOpaque)), &opaque); err != nil {
- return err
- }
-
- // start the child driver
- quit := make(chan struct{})
- errCh := make(chan error)
- go func() {
- d := rkbuiltin.NewChildDriver(os.Stderr)
- dErr := d.RunChildDriver(opaque, quit)
- errCh <- dErr
- }()
- defer func() {
- logrus.Info("Stopping child driver")
- quit <- struct{}{}
- if err := <-errCh; err != nil {
- logrus.WithError(err).Warn("Child driver returned error on exit")
- }
- }()
-
- // wait for stdin to be closed
- if _, err := ioutil.ReadAll(os.Stdin); err != nil {
- return err
- }
- return nil
-}
-
-type logrusWriter struct {
- prefix string
-}
-
-func (w *logrusWriter) Write(p []byte) (int, error) {
- logrus.Infof("%s%s", w.prefix, string(p))
- return len(p), nil
-}