github.com/sams1990/dockerrepo@v17.12.1-ce-rc2+incompatible/plugin/v2/plugin_linux.go (about)

     1  // +build linux
     2  
     3  package v2
     4  
     5  import (
     6  	"os"
     7  	"path/filepath"
     8  	"runtime"
     9  	"strings"
    10  
    11  	"github.com/docker/docker/api/types"
    12  	"github.com/docker/docker/oci"
    13  	"github.com/docker/docker/pkg/system"
    14  	specs "github.com/opencontainers/runtime-spec/specs-go"
    15  	"github.com/pkg/errors"
    16  )
    17  
    18  // InitSpec creates an OCI spec from the plugin's config.
    19  func (p *Plugin) InitSpec(execRoot string) (*specs.Spec, error) {
    20  	s := oci.DefaultSpec()
    21  	s.Root = &specs.Root{
    22  		Path:     p.Rootfs,
    23  		Readonly: false, // TODO: all plugins should be readonly? settable in config?
    24  	}
    25  
    26  	userMounts := make(map[string]struct{}, len(p.PluginObj.Settings.Mounts))
    27  	for _, m := range p.PluginObj.Settings.Mounts {
    28  		userMounts[m.Destination] = struct{}{}
    29  	}
    30  
    31  	execRoot = filepath.Join(execRoot, p.PluginObj.ID)
    32  	if err := os.MkdirAll(execRoot, 0700); err != nil {
    33  		return nil, errors.WithStack(err)
    34  	}
    35  
    36  	mounts := append(p.PluginObj.Config.Mounts, types.PluginMount{
    37  		Source:      &execRoot,
    38  		Destination: defaultPluginRuntimeDestination,
    39  		Type:        "bind",
    40  		Options:     []string{"rbind", "rshared"},
    41  	})
    42  
    43  	if p.PluginObj.Config.Network.Type != "" {
    44  		// TODO: if net == bridge, use libnetwork controller to create a new plugin-specific bridge, bind mount /etc/hosts and /etc/resolv.conf look at the docker code (allocateNetwork, initialize)
    45  		if p.PluginObj.Config.Network.Type == "host" {
    46  			oci.RemoveNamespace(&s, specs.LinuxNamespaceType("network"))
    47  		}
    48  		etcHosts := "/etc/hosts"
    49  		resolvConf := "/etc/resolv.conf"
    50  		mounts = append(mounts,
    51  			types.PluginMount{
    52  				Source:      &etcHosts,
    53  				Destination: etcHosts,
    54  				Type:        "bind",
    55  				Options:     []string{"rbind", "ro"},
    56  			},
    57  			types.PluginMount{
    58  				Source:      &resolvConf,
    59  				Destination: resolvConf,
    60  				Type:        "bind",
    61  				Options:     []string{"rbind", "ro"},
    62  			})
    63  	}
    64  	if p.PluginObj.Config.PidHost {
    65  		oci.RemoveNamespace(&s, specs.LinuxNamespaceType("pid"))
    66  	}
    67  
    68  	if p.PluginObj.Config.IpcHost {
    69  		oci.RemoveNamespace(&s, specs.LinuxNamespaceType("ipc"))
    70  	}
    71  
    72  	for _, mnt := range mounts {
    73  		m := specs.Mount{
    74  			Destination: mnt.Destination,
    75  			Type:        mnt.Type,
    76  			Options:     mnt.Options,
    77  		}
    78  		if mnt.Source == nil {
    79  			return nil, errors.New("mount source is not specified")
    80  		}
    81  		m.Source = *mnt.Source
    82  		s.Mounts = append(s.Mounts, m)
    83  	}
    84  
    85  	for i, m := range s.Mounts {
    86  		if strings.HasPrefix(m.Destination, "/dev/") {
    87  			if _, ok := userMounts[m.Destination]; ok {
    88  				s.Mounts = append(s.Mounts[:i], s.Mounts[i+1:]...)
    89  			}
    90  		}
    91  	}
    92  
    93  	if p.PluginObj.Config.PropagatedMount != "" {
    94  		p.PropagatedMount = filepath.Join(p.Rootfs, p.PluginObj.Config.PropagatedMount)
    95  		s.Linux.RootfsPropagation = "rshared"
    96  	}
    97  
    98  	if p.PluginObj.Config.Linux.AllowAllDevices {
    99  		s.Linux.Resources.Devices = []specs.LinuxDeviceCgroup{{Allow: true, Access: "rwm"}}
   100  	}
   101  	for _, dev := range p.PluginObj.Settings.Devices {
   102  		path := *dev.Path
   103  		d, dPermissions, err := oci.DevicesFromPath(path, path, "rwm")
   104  		if err != nil {
   105  			return nil, errors.WithStack(err)
   106  		}
   107  		s.Linux.Devices = append(s.Linux.Devices, d...)
   108  		s.Linux.Resources.Devices = append(s.Linux.Resources.Devices, dPermissions...)
   109  	}
   110  
   111  	envs := make([]string, 1, len(p.PluginObj.Settings.Env)+1)
   112  	envs[0] = "PATH=" + system.DefaultPathEnv(runtime.GOOS)
   113  	envs = append(envs, p.PluginObj.Settings.Env...)
   114  
   115  	args := append(p.PluginObj.Config.Entrypoint, p.PluginObj.Settings.Args...)
   116  	cwd := p.PluginObj.Config.WorkDir
   117  	if len(cwd) == 0 {
   118  		cwd = "/"
   119  	}
   120  	s.Process.Terminal = false
   121  	s.Process.Args = args
   122  	s.Process.Cwd = cwd
   123  	s.Process.Env = envs
   124  
   125  	caps := s.Process.Capabilities
   126  	caps.Bounding = append(caps.Bounding, p.PluginObj.Config.Linux.Capabilities...)
   127  	caps.Permitted = append(caps.Permitted, p.PluginObj.Config.Linux.Capabilities...)
   128  	caps.Inheritable = append(caps.Inheritable, p.PluginObj.Config.Linux.Capabilities...)
   129  	caps.Effective = append(caps.Effective, p.PluginObj.Config.Linux.Capabilities...)
   130  
   131  	return &s, nil
   132  }