mirror of
https://github.com/opencontainers/runc.git
synced 2026-07-11 06:03:57 +08:00
Aleksa Sarai
e34a0a0936
This is primarily done out of an abudance of caution against runc exec being attacked by a container where /dev/pts/ptmx has been replaced with some other bad inode (a disconnected NFS handle, a symlink that goes through a leaked runc file descriptor to reference a host ptmx, etc). Unfortunately, we cannot trivially verify that /dev/pts/ptmx is actually the /dev/pts from the container without storing stuff like the fsid in the runc state.json, which is probably not worth the extra effort. This should at least avoid the most concerning cases. Reported-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
45 lines
1.3 KiB
Go
45 lines
1.3 KiB
Go
/*
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Copyright The containerd Authors.
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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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http://www.apache.org/licenses/LICENSE-2.0
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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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package console
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import (
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"bytes"
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"golang.org/x/sys/unix"
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)
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const (
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cmdTcGet = unix.TIOCGETA
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cmdTcSet = unix.TIOCSETA
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)
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// unlockpt unlocks the slave pseudoterminal device corresponding to the master pseudoterminal referred to by f.
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// unlockpt should be called before opening the slave side of a pty.
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// This does not exist on NetBSD, it does not allocate controlling terminals on open
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func unlockpt(f File) error {
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return nil
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}
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// ptsname retrieves the name of the first available pts for the given master.
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func ptsname(f File) (string, error) {
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ptm, err := unix.IoctlGetPtmget(int(f.Fd()), unix.TIOCPTSNAME)
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if err != nil {
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return "", err
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}
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return string(ptm.Sn[:bytes.IndexByte(ptm.Sn[:], 0)]), nil
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}
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