// We have a dummy version of this call in posix.go.
// Windows does not implement the syscall.Stat_t type we
// need, but the *nixes do. We use this in util.AddToArchive
// to set owner/group on files being added to a tar archive.
func GetOwnerAndGroup(finfo os.FileInfo, header *tar.Header) {
systat := finfo.Sys().(*syscall.Stat_t)
if systat != nil {
header.Uid = int(systat.Uid)
header.Gid = int(systat.Gid)
}
}
// fills tar.Header missing information (uid/gid, username/groupname, times ...)
func FillHeader(hdr *tar.Header) {
var cuname string
cuid := os.Getuid()
if curr, err := user.LookupId(fmt.Sprintf("%d", cuid)); err == nil {
cuname = curr.Username
}
if hdr.Uid == 0 {
if hdr.Uname == "" {
hdr.Uid = cuid
hdr.Uname = cuname
} else {
if usr, err := user.Lookup(hdr.Uname); err == nil {
if i, err := fmt.Sscanf("%d", usr.Uid); err == nil {
hdr.Uid = i
hdr.Uname = usr.Username
}
}
}
}
if hdr.Gid == 0 {
if hdr.Gname == "" {
if hdr.Uid != 0 {
if usr, err := user.LookupId(fmt.Sprintf("%d", hdr.Uid)); err == nil {
if i, err := fmt.Sscanf("%d", usr.Gid); err == nil {
hdr.Gid = i
}
}
}
}
}
if hdr.ModTime.IsZero() {
hdr.ModTime = time.Now()
}
if hdr.AccessTime.IsZero() {
hdr.AccessTime = hdr.ModTime
}
if hdr.ChangeTime.IsZero() {
hdr.ChangeTime = hdr.ModTime
}
}
func writeTarEntry(tw *tar.Writer, name string, data []byte) error {
h := new(tar.Header)
h.Name = name
h.Uid = 1000
h.Gid = 1000
h.Mode = 0755
h.Size = int64(len(data))
if err := tw.WriteHeader(h); err != nil {
return err
}
if _, err := tw.Write(data); err != nil {
return err
}
return nil
}
func populateHeaderUnix(h *tar.Header, fi os.FileInfo, seen map[uint64]string) {
st, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
return
}
h.Uid = int(st.Uid)
h.Gid = int(st.Gid)
// If we have already seen this inode, generate a hardlink
p, ok := seen[uint64(st.Ino)]
if ok {
h.Linkname = p
h.Typeflag = tar.TypeLink
} else {
seen[uint64(st.Ino)] = h.Name
}
}
func populateHeaderUnix(h *tar.Header, fi os.FileInfo, seen map[uint64]string) {
st, ok := fi.Sys().(*syscall.Stat_t)
if !ok {
return
}
h.Uid = int(st.Uid)
h.Gid = int(st.Gid)
if st.Mode&syscall.S_IFMT == syscall.S_IFBLK || st.Mode&syscall.S_IFMT == syscall.S_IFCHR {
h.Devminor = int64(C.my_minor(C.dev_t(st.Rdev)))
h.Devmajor = int64(C.my_major(C.dev_t(st.Rdev)))
}
// If we have already seen this inode, generate a hardlink
p, ok := seen[uint64(st.Ino)]
if ok {
h.Linkname = p
h.Typeflag = tar.TypeLink
} else {
seen[uint64(st.Ino)] = h.Name
}
}
func fakeTar() (io.Reader, error) {
uid := os.Getuid()
gid := os.Getgid()
content := []byte("Hello world!\n")
buf := new(bytes.Buffer)
tw := tar.NewWriter(buf)
for _, name := range []string{"/etc/postgres/postgres.conf", "/etc/passwd", "/var/log/postgres/postgres.conf"} {
hdr := new(tar.Header)
// Leaving these fields blank requires root privileges
hdr.Uid = uid
hdr.Gid = gid
hdr.Size = int64(len(content))
hdr.Name = name
if err := tw.WriteHeader(hdr); err != nil {
return nil, err
}
tw.Write([]byte(content))
}
tw.Close()
return buf, nil
}
func TestUntarIDMappings(t *testing.T) {
StartTest(t)
defer FinishTest(t)
// create a buffer and tar.Writer
buffer := bytes.NewBufferString("")
archive := tar.NewWriter(buffer)
writeDirectoryWithOwners := func(name string, uid, gid int) {
header := new(tar.Header)
header.Name = name + "/"
header.Typeflag = tar.TypeDir
header.Mode = 0755
header.Mode |= c_ISDIR
header.ModTime = time.Now()
header.Uid = uid
header.Gid = gid
TestExpectSuccess(t, archive.WriteHeader(header))
}
writeFileWithOwners := func(name, contents string, uid, gid int) {
b := []byte(contents)
header := new(tar.Header)
header.Name = name
header.Typeflag = tar.TypeReg
header.Mode = 0644
header.Mode |= c_ISREG
header.ModTime = time.Now()
header.Size = int64(len(b))
header.Uid = uid
header.Gid = gid
TestExpectSuccess(t, archive.WriteHeader(header))
_, err := archive.Write(b)
TestExpectSuccess(t, err)
TestExpectSuccess(t, archive.Flush())
}
writeDirectoryWithOwners(".", 0, 0)
writeFileWithOwners("./foo", "foo", 0, 0)
archive.Close()
// setup our mapping func
usr, err := user.Current()
TestExpectSuccess(t, err)
myUid, err := strconv.Atoi(usr.Uid)
TestExpectSuccess(t, err)
myGid, err := strconv.Atoi(usr.Gid)
TestExpectSuccess(t, err)
uidFuncCalled := false
gidFuncCalled := false
uidMappingFunc := func(uid int) (int, error) {
uidFuncCalled = true
TestEqual(t, uid, 0)
return myUid, nil
}
gidMappingFunc := func(gid int) (int, error) {
gidFuncCalled = true
TestEqual(t, gid, 0)
return myGid, nil
}
// extract
tempDir := TempDir(t)
r := bytes.NewReader(buffer.Bytes())
u := NewUntar(r, tempDir)
u.PreserveOwners = true
u.OwnerMappingFunc = uidMappingFunc
u.GroupMappingFunc = gidMappingFunc
TestExpectSuccess(t, u.Extract())
// verify it was called
TestEqual(t, uidFuncCalled, true)
TestEqual(t, gidFuncCalled, true)
// verify the file
stat, err := os.Stat(path.Join(tempDir, "foo"))
TestExpectSuccess(t, err)
sys := stat.Sys().(*syscall.Stat_t)
TestEqual(t, sys.Uid, uint32(myUid))
TestEqual(t, sys.Gid, uint32(myGid))
}
func createArchive() int {
archive := tar.NewWriter(output)
defer archive.Close()
exit_value := 0
for _, f := range fileList {
err := filepath.Walk(f, func(path string, info os.FileInfo, err error) error {
if err != nil {
return err
}
if verbose {
fmt.Fprintf(os.Stderr, "%s\n", path)
}
var hdr tar.Header
hdr.Name = path
hdr.Size = info.Size()
hdr.Mode = int64(info.Mode())
hdr.ModTime = info.ModTime()
// this is not portable:
hdr.Uid = int(info.Sys().(*syscall.Stat_t).Uid)
hdr.Gid = int(info.Sys().(*syscall.Stat_t).Gid)
if user, err := user.LookupId(fmt.Sprintf("%d", hdr.Uid)); err == nil {
hdr.Uname = user.Name
}
// TODO: lookup group, too.
switch info.Mode() & os.ModeType {
case 0:
hdr.Typeflag = tar.TypeReg
case os.ModeDir:
hdr.Typeflag = tar.TypeDir
case os.ModeSymlink:
hdr.Typeflag = tar.TypeSymlink
linkname, err := os.Readlink(path)
if err != nil {
fmt.Fprintf(os.Stderr, "Warning: can't readlink a symlink: %v\n", err)
return nil
} else {
hdr.Linkname = linkname
}
case os.ModeNamedPipe:
hdr.Typeflag = tar.TypeFifo
case os.ModeSocket:
fmt.Fprintf(os.Stderr, "Warning: can't tar a socket\n")
return nil
case os.ModeDevice:
fmt.Fprintf(os.Stderr, "Warning: device files are currently unsupported\n")
return nil
/*
if (info.Mode() & os.ModeCharDevice) != 0 {
os.Typeflag = tar.TypeChar
} else {
os.Typeflag = tar.TypeBlock
}
*/
}
if err := archive.WriteHeader(&hdr); err != nil {
fmt.Fprintf(os.Stderr, "Writing archive header for %s failed: %v\n", path, err)
exit_value = 1
return nil
}
defer archive.Flush()
if hdr.Typeflag == tar.TypeReg {
if f, err := os.Open(path); err != nil {
fmt.Fprintf(os.Stderr, "Opening file %s failed: %v\n", path, err)
exit_value = 1
return nil
} else {
io.Copy(archive, f)
f.Close()
}
}
return nil
})
if err != nil {
fmt.Fprintf(os.Stderr, "An error occured: %v\n", err)
exit_value = 1
}
}
return exit_value
}
