go.ligato.io/vpp-agent/v3@v3.5.0/plugins/linux/nsplugin/linuxcalls/system_api.go (about)

     1  // Copyright (c) 2018 Cisco and/or its affiliates.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at:
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package linuxcalls
    16  
    17  import (
    18  	"os"
    19  
    20  	"github.com/vishvananda/netns"
    21  )
    22  
    23  // SystemAPI defines all methods required for managing network namespaces
    24  // on the system level.
    25  type SystemAPI interface {
    26  	FileSystemAPI
    27  	NetworkNamespaceAPI
    28  }
    29  
    30  // FileSystemAPI defines all methods used to access file system.
    31  type FileSystemAPI interface {
    32  	// FileExists checks whether the file exists.
    33  	FileExists(name string) (bool, error)
    34  	// OpenFile opens a file.
    35  	OpenFile(name string, flag int, perm os.FileMode) (*os.File, error)
    36  	// MkDirAll creates a directory with all parent directories.
    37  	MkDirAll(path string, perm os.FileMode) error
    38  	// Remove removes named file or directory.
    39  	Remove(name string) error
    40  	// Mount makes resources available.
    41  	Mount(source string, target string, fsType string, flags uintptr, data string) error
    42  	// Unmount resources.
    43  	Unmount(target string, flags int) (err error)
    44  }
    45  
    46  // NetworkNamespaceAPI defines methods for low-level handling of network namespaces.
    47  type NetworkNamespaceAPI interface {
    48  	// NewNetworkNamespace creates a new namespace and returns a handle to manage it further.
    49  	NewNetworkNamespace() (ns netns.NsHandle, err error)
    50  	// DuplicateNamespaceHandle duplicates network namespace handle.
    51  	DuplicateNamespaceHandle(ns netns.NsHandle) (netns.NsHandle, error)
    52  	// GetCurrentNamespace gets a handle to the current threads network namespace.
    53  	GetCurrentNamespace() (ns netns.NsHandle, err error)
    54  	// GetNamespaceFromPath gets a handle to a network namespace identified
    55  	// by the path.
    56  	GetNamespaceFromPath(path string) (ns netns.NsHandle, err error)
    57  	// GetNamespaceFromPid gets a handle to the network namespace of a given pid.
    58  	GetNamespaceFromPid(pid int) (ns netns.NsHandle, err error)
    59  	// GetNamespaceFromName gets a handle to a named network namespace such as one
    60  	// created by `ip netns add`.
    61  	GetNamespaceFromName(name string) (ns netns.NsHandle, err error)
    62  	// SetNamespace sets the current namespace to the namespace represented by the handle.
    63  	SetNamespace(ns netns.NsHandle) (err error)
    64  }
    65  
    66  // systemHandler implements SystemAPI using actual syscalls (i.e. not suitable for tests).
    67  type systemHandler struct {
    68  }
    69  
    70  // NewSystemHandler returns new handler.
    71  func NewSystemHandler() SystemAPI {
    72  	return &systemHandler{}
    73  }