diff options
Diffstat (limited to 'vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go')
-rw-r--r-- | vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go b/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go new file mode 100644 index 000000000..7f2ef8504 --- /dev/null +++ b/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go @@ -0,0 +1,78 @@ +// +build linux + +package selinux + +import ( + "syscall" + "unsafe" +) + +var _zero uintptr + +// Returns a []byte slice if the xattr is set and nil otherwise +// Requires path and its attribute as arguments +func lgetxattr(path string, attr string) ([]byte, error) { + var sz int + pathBytes, err := syscall.BytePtrFromString(path) + if err != nil { + return nil, err + } + attrBytes, err := syscall.BytePtrFromString(attr) + if err != nil { + return nil, err + } + + // Start with a 128 length byte array + sz = 128 + dest := make([]byte, sz) + destBytes := unsafe.Pointer(&dest[0]) + _sz, _, errno := syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0) + + switch { + case errno == syscall.ENODATA: + return nil, errno + case errno == syscall.ENOTSUP: + return nil, errno + case errno == syscall.ERANGE: + // 128 byte array might just not be good enough, + // A dummy buffer is used ``uintptr(0)`` to get real size + // of the xattrs on disk + _sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(unsafe.Pointer(nil)), uintptr(0), 0, 0) + sz = int(_sz) + if sz < 0 { + return nil, errno + } + dest = make([]byte, sz) + destBytes := unsafe.Pointer(&dest[0]) + _sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0) + if errno != 0 { + return nil, errno + } + case errno != 0: + return nil, errno + } + sz = int(_sz) + return dest[:sz], nil +} + +func lsetxattr(path string, attr string, data []byte, flags int) error { + pathBytes, err := syscall.BytePtrFromString(path) + if err != nil { + return err + } + attrBytes, err := syscall.BytePtrFromString(attr) + if err != nil { + return err + } + var dataBytes unsafe.Pointer + if len(data) > 0 { + dataBytes = unsafe.Pointer(&data[0]) + } else { + dataBytes = unsafe.Pointer(&_zero) + } + _, _, errno := syscall.Syscall6(syscall.SYS_LSETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(dataBytes), uintptr(len(data)), uintptr(flags), 0) + if errno != 0 { + return errno + } + return nil +} |