runc/configs/namespaces.go

110 lines
2.1 KiB
Go

package configs
import (
"fmt"
"syscall"
)
type NamespaceType string
const (
NEWNET NamespaceType = "NEWNET"
NEWPID NamespaceType = "NEWPID"
NEWNS NamespaceType = "NEWNS"
NEWUTS NamespaceType = "NEWUTS"
NEWIPC NamespaceType = "NEWIPC"
NEWUSER NamespaceType = "NEWUSER"
)
// Namespace defines configuration for each namespace. It specifies an
// alternate path that is able to be joined via setns.
type Namespace struct {
Type NamespaceType `json:"type"`
Path string `json:"path"`
}
func (n *Namespace) Syscall() int {
return namespaceInfo[n.Type]
}
func (n *Namespace) GetPath(pid int) string {
if n.Path != "" {
return n.Path
}
return fmt.Sprintf("/proc/%d/ns/%s", pid, n.file())
}
func (n *Namespace) file() string {
file := ""
switch n.Type {
case NEWNET:
file = "net"
case NEWNS:
file = "mnt"
case NEWPID:
file = "pid"
case NEWIPC:
file = "ipc"
case NEWUSER:
file = "user"
case NEWUTS:
file = "uts"
}
return file
}
type Namespaces []Namespace
func (n *Namespaces) Remove(t NamespaceType) bool {
i := n.index(t)
if i == -1 {
return false
}
*n = append((*n)[:i], (*n)[i+1:]...)
return true
}
func (n *Namespaces) Add(t NamespaceType, path string) {
i := n.index(t)
if i == -1 {
*n = append(*n, Namespace{Type: t, Path: path})
return
}
(*n)[i].Path = path
}
func (n *Namespaces) index(t NamespaceType) int {
for i, ns := range *n {
if ns.Type == t {
return i
}
}
return -1
}
func (n *Namespaces) Contains(t NamespaceType) bool {
return n.index(t) != -1
}
var namespaceInfo = map[NamespaceType]int{
NEWNET: syscall.CLONE_NEWNET,
NEWNS: syscall.CLONE_NEWNS,
NEWUSER: syscall.CLONE_NEWUSER,
NEWIPC: syscall.CLONE_NEWIPC,
NEWUTS: syscall.CLONE_NEWUTS,
NEWPID: syscall.CLONE_NEWPID,
}
// CloneFlags parses the container's Namespaces options to set the correct
// flags on clone, unshare. This functions returns flags only for new namespaces.
func (n *Namespaces) CloneFlags() uintptr {
var flag int
for _, v := range *n {
if v.Path != "" {
continue
}
flag |= namespaceInfo[v.Type]
}
return uintptr(flag)
}