fortify/acl/c.go

100 lines
1.7 KiB
Go

package acl
import (
"errors"
"fmt"
"syscall"
"unsafe"
)
//#include <stdlib.h>
//#include <sys/acl.h>
//#include <acl/libacl.h>
//#cgo linux LDFLAGS: -lacl
import "C"
type acl struct {
val C.acl_t
freed bool
}
func aclGetFile(path string, t C.acl_type_t) (*acl, error) {
p := C.CString(path)
a, err := C.acl_get_file(p, t)
C.free(unsafe.Pointer(p))
if errors.Is(err, syscall.ENODATA) {
err = nil
}
return &acl{val: a, freed: false}, err
}
func (a *acl) setFile(path string, t C.acl_type_t) error {
if C.acl_valid(a.val) != 0 {
return fmt.Errorf("invalid acl")
}
p := C.CString(path)
_, err := C.acl_set_file(p, t, a.val)
C.free(unsafe.Pointer(p))
return err
}
func (a *acl) removeEntry(tt C.acl_tag_t, tq int) error {
var e C.acl_entry_t
// get first entry
if r, err := C.acl_get_entry(a.val, C.ACL_FIRST_ENTRY, &e); err != nil {
return err
} else if r == 0 {
// return on acl with no entries
return nil
}
for {
if r, err := C.acl_get_entry(a.val, C.ACL_NEXT_ENTRY, &e); err != nil {
return err
} else if r == 0 {
// return on drained acl
return nil
}
var (
q int
t C.acl_tag_t
)
// get current entry tag type
if _, err := C.acl_get_tag_type(e, &t); err != nil {
return err
}
// get current entry qualifier
if rq, err := C.acl_get_qualifier(e); err != nil {
// neither ACL_USER nor ACL_GROUP
if errors.Is(err, syscall.EINVAL) {
continue
}
return err
} else {
q = *(*int)(rq)
C.acl_free(rq)
}
// delete on match
if t == tt && q == tq {
_, err := C.acl_delete_entry(a.val, e)
return err
}
}
}
func (a *acl) free() {
if a.freed {
panic("acl already freed")
}
C.acl_free(unsafe.Pointer(a.val))
a.freed = true
}