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@@ -1,93 +0,0 @@
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-// +build linux
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-
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-package utils
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-
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-/*
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- * Copyright 2016, 2017 SUSE LLC
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- *
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- * Licensed under the Apache License, Version 2.0 (the "License");
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- * you may not use this file except in compliance with the License.
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- * You may obtain a copy of the License at
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- *
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- * http://www.apache.org/licenses/LICENSE-2.0
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- *
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- * Unless required by applicable law or agreed to in writing, software
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- * distributed under the License is distributed on an "AS IS" BASIS,
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- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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- * See the License for the specific language governing permissions and
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- * limitations under the License.
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- */
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-
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-import (
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- "fmt"
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- "os"
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-
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- "golang.org/x/sys/unix"
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-)
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-
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-// MaxSendfdLen is the maximum length of the name of a file descriptor being
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-// sent using SendFd. The name of the file handle returned by RecvFd will never
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-// be larger than this value.
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-const MaxNameLen = 4096
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-
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-// oobSpace is the size of the oob slice required to store a single FD. Note
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-// that unix.UnixRights appears to make the assumption that fd is always int32,
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-// so sizeof(fd) = 4.
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-var oobSpace = unix.CmsgSpace(4)
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-
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-// RecvFd waits for a file descriptor to be sent over the given AF_UNIX
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-// socket. The file name of the remote file descriptor will be recreated
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-// locally (it is sent as non-auxiliary data in the same payload).
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-func RecvFd(socket *os.File) (*os.File, error) {
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- // For some reason, unix.Recvmsg uses the length rather than the capacity
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- // when passing the msg_controllen and other attributes to recvmsg. So we
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- // have to actually set the length.
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- name := make([]byte, MaxNameLen)
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- oob := make([]byte, oobSpace)
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-
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- sockfd := socket.Fd()
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- n, oobn, _, _, err := unix.Recvmsg(int(sockfd), name, oob, 0)
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- if err != nil {
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- return nil, err
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- }
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-
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- if n >= MaxNameLen || oobn != oobSpace {
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- return nil, fmt.Errorf("recvfd: incorrect number of bytes read (n=%d oobn=%d)", n, oobn)
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- }
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-
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- // Truncate.
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- name = name[:n]
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- oob = oob[:oobn]
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-
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- scms, err := unix.ParseSocketControlMessage(oob)
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- if err != nil {
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- return nil, err
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- }
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- if len(scms) != 1 {
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- return nil, fmt.Errorf("recvfd: number of SCMs is not 1: %d", len(scms))
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- }
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- scm := scms[0]
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-
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- fds, err := unix.ParseUnixRights(&scm)
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- if err != nil {
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- return nil, err
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- }
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- if len(fds) != 1 {
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- return nil, fmt.Errorf("recvfd: number of fds is not 1: %d", len(fds))
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- }
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- fd := uintptr(fds[0])
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-
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- return os.NewFile(fd, string(name)), nil
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-}
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-
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-// SendFd sends a file descriptor over the given AF_UNIX socket. In
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-// addition, the file.Name() of the given file will also be sent as
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-// non-auxiliary data in the same payload (allowing to send contextual
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-// information for a file descriptor).
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-func SendFd(socket *os.File, name string, fd uintptr) error {
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- if len(name) >= MaxNameLen {
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- return fmt.Errorf("sendfd: filename too long: %s", name)
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- }
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- oob := unix.UnixRights(int(fd))
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- return unix.Sendmsg(int(socket.Fd()), []byte(name), oob, nil, 0)
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-}
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