1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121
|
package oci
import (
"context"
"os"
"strconv"
"strings"
"github.com/containerd/containerd/containers"
containerdoci "github.com/containerd/containerd/oci"
"github.com/containerd/continuity/fs"
"github.com/moby/sys/user"
specs "github.com/opencontainers/runtime-spec/specs-go"
"github.com/pkg/errors"
)
func GetUser(root, username string) (uint32, uint32, []uint32, error) {
var isDefault bool
if username == "" {
username = "0"
isDefault = true
}
// fast path from uid/gid
if uid, gid, err := ParseUIDGID(username); err == nil {
return uid, gid, nil, nil
}
passwdFile, err := openUserFile(root, "/etc/passwd")
if err == nil {
defer passwdFile.Close()
}
groupFile, err := openUserFile(root, "/etc/group")
if err == nil {
defer groupFile.Close()
}
execUser, err := user.GetExecUser(username, nil, passwdFile, groupFile)
if err != nil {
if isDefault {
return 0, 0, nil, nil
}
return 0, 0, nil, err
}
var sgids []uint32
for _, g := range execUser.Sgids {
sgids = append(sgids, uint32(g))
}
return uint32(execUser.Uid), uint32(execUser.Gid), sgids, nil
}
// ParseUIDGID takes the fast path to parse UID and GID if and only if they are both provided
func ParseUIDGID(str string) (uid uint32, gid uint32, err error) {
if str == "" {
return 0, 0, nil
}
parts := strings.SplitN(str, ":", 2)
if len(parts) == 1 {
return 0, 0, errors.New("groups ID is not provided")
}
if uid, err = parseUID(parts[0]); err != nil {
return 0, 0, err
}
if gid, err = parseUID(parts[1]); err != nil {
return 0, 0, err
}
return
}
func openUserFile(root, p string) (*os.File, error) {
p, err := fs.RootPath(root, p)
if err != nil {
return nil, err
}
return os.Open(p)
}
func parseUID(str string) (uint32, error) {
if str == "root" {
return 0, nil
}
uid, err := strconv.ParseUint(str, 10, 32)
if err != nil {
return 0, err
}
return uint32(uid), nil
}
// WithUIDGID allows the UID and GID for the Process to be set
// FIXME: This is a temporeray fix for the missing supplementary GIDs from containerd
// once the PR in containerd is merged we should remove this function.
func WithUIDGID(uid, gid uint32, sgids []uint32) containerdoci.SpecOpts {
return func(_ context.Context, _ containerdoci.Client, _ *containers.Container, s *containerdoci.Spec) error {
defer ensureAdditionalGids(s)
setProcess(s)
s.Process.User.UID = uid
s.Process.User.GID = gid
s.Process.User.AdditionalGids = sgids
return nil
}
}
// setProcess sets Process to empty if unset
// FIXME: Same on this one. Need to be removed after containerd fix merged
func setProcess(s *containerdoci.Spec) {
if s.Process == nil {
s.Process = &specs.Process{}
}
}
// ensureAdditionalGids ensures that the primary GID is also included in the additional GID list.
// From https://github.com/containerd/containerd/blob/v1.7.0-beta.4/oci/spec_opts.go#L124-L133
func ensureAdditionalGids(s *containerdoci.Spec) {
setProcess(s)
for _, f := range s.Process.User.AdditionalGids {
if f == s.Process.User.GID {
return
}
}
s.Process.User.AdditionalGids = append([]uint32{s.Process.User.GID}, s.Process.User.AdditionalGids...)
}
|