From 2eaf54dd597d8aaa56ad6274e0c1e585d9b9c063 Mon Sep 17 00:00:00 2001 From: Ayush Ranjan Date: Tue, 1 Sep 2020 14:41:54 -0700 Subject: Refactor tty codebase to use master-replica terminology. Updates #2972 PiperOrigin-RevId: 329584905 --- pkg/sentry/fs/host/tty.go | 2 +- pkg/sentry/fs/tty/BUILD | 2 +- pkg/sentry/fs/tty/dir.go | 46 +++---- pkg/sentry/fs/tty/fs.go | 4 +- pkg/sentry/fs/tty/line_discipline.go | 22 +-- pkg/sentry/fs/tty/master.go | 4 +- pkg/sentry/fs/tty/queue.go | 2 +- pkg/sentry/fs/tty/replica.go | 186 +++++++++++++++++++++++++ pkg/sentry/fs/tty/slave.go | 185 ------------------------- pkg/sentry/fs/tty/terminal.go | 18 +-- pkg/sentry/fs/tty/tty_test.go | 4 +- pkg/sentry/fsimpl/devpts/BUILD | 2 +- pkg/sentry/fsimpl/devpts/devpts.go | 34 ++--- pkg/sentry/fsimpl/devpts/devpts_test.go | 4 +- pkg/sentry/fsimpl/devpts/line_discipline.go | 22 +-- pkg/sentry/fsimpl/devpts/master.go | 4 +- pkg/sentry/fsimpl/devpts/queue.go | 2 +- pkg/sentry/fsimpl/devpts/replica.go | 205 ++++++++++++++++++++++++++++ pkg/sentry/fsimpl/devpts/slave.go | 205 ---------------------------- pkg/sentry/fsimpl/devpts/terminal.go | 16 +-- pkg/sentry/fsimpl/host/host.go | 2 +- 21 files changed, 486 insertions(+), 485 deletions(-) create mode 100644 pkg/sentry/fs/tty/replica.go delete mode 100644 pkg/sentry/fs/tty/slave.go create mode 100644 pkg/sentry/fsimpl/devpts/replica.go delete mode 100644 pkg/sentry/fsimpl/devpts/slave.go (limited to 'pkg/sentry') diff --git a/pkg/sentry/fs/host/tty.go b/pkg/sentry/fs/host/tty.go index 67a807f9d..87d56a51d 100644 --- a/pkg/sentry/fs/host/tty.go +++ b/pkg/sentry/fs/host/tty.go @@ -54,7 +54,7 @@ type TTYFileOperations struct { func newTTYFile(ctx context.Context, dirent *fs.Dirent, flags fs.FileFlags, iops *inodeOperations) *fs.File { return fs.NewFile(ctx, dirent, flags, &TTYFileOperations{ fileOperations: fileOperations{iops: iops}, - termios: linux.DefaultSlaveTermios, + termios: linux.DefaultReplicaTermios, }) } diff --git a/pkg/sentry/fs/tty/BUILD b/pkg/sentry/fs/tty/BUILD index b3f5a8244..fdd5a40d5 100644 --- a/pkg/sentry/fs/tty/BUILD +++ b/pkg/sentry/fs/tty/BUILD @@ -10,7 +10,7 @@ go_library( "line_discipline.go", "master.go", "queue.go", - "slave.go", + "replica.go", "terminal.go", ], visibility = ["//pkg/sentry:internal"], diff --git a/pkg/sentry/fs/tty/dir.go b/pkg/sentry/fs/tty/dir.go index 463f6189e..c2da80bc2 100644 --- a/pkg/sentry/fs/tty/dir.go +++ b/pkg/sentry/fs/tty/dir.go @@ -37,14 +37,14 @@ import ( // This indirectly manages all terminals within the mount. // // New Terminals are created by masterInodeOperations.GetFile, which registers -// the slave Inode in the this directory for discovery via Lookup/Readdir. The -// slave inode is unregistered when the master file is Released, as the slave +// the replica Inode in the this directory for discovery via Lookup/Readdir. The +// replica inode is unregistered when the master file is Released, as the replica // is no longer discoverable at that point. // // References on the underlying Terminal are held by masterFileOperations and -// slaveInodeOperations. +// replicaInodeOperations. // -// masterInodeOperations and slaveInodeOperations hold a pointer to +// masterInodeOperations and replicaInodeOperations hold a pointer to // dirInodeOperations, which is reference counted by the refcount their // corresponding Dirents hold on their parent (this directory). // @@ -76,16 +76,16 @@ type dirInodeOperations struct { // master is the master PTY inode. master *fs.Inode - // slaves contains the slave inodes reachable from the directory. + // replicas contains the replica inodes reachable from the directory. // - // A new slave is added by allocateTerminal and is removed by + // A new replica is added by allocateTerminal and is removed by // masterFileOperations.Release. // - // A reference is held on every slave in the map. - slaves map[uint32]*fs.Inode + // A reference is held on every replica in the map. + replicas map[uint32]*fs.Inode // dentryMap is a SortedDentryMap used to implement Readdir containing - // the master and all entries in slaves. + // the master and all entries in replicas. dentryMap *fs.SortedDentryMap // next is the next pty index to use. @@ -101,7 +101,7 @@ func newDir(ctx context.Context, m *fs.MountSource) *fs.Inode { d := &dirInodeOperations{ InodeSimpleAttributes: fsutil.NewInodeSimpleAttributes(ctx, fs.RootOwner, fs.FilePermsFromMode(0555), linux.DEVPTS_SUPER_MAGIC), msrc: m, - slaves: make(map[uint32]*fs.Inode), + replicas: make(map[uint32]*fs.Inode), dentryMap: fs.NewSortedDentryMap(nil), } // Linux devpts uses a default mode of 0000 for ptmx which can be @@ -133,7 +133,7 @@ func (d *dirInodeOperations) Release(ctx context.Context) { defer d.mu.Unlock() d.master.DecRef(ctx) - if len(d.slaves) != 0 { + if len(d.replicas) != 0 { panic(fmt.Sprintf("devpts directory still contains active terminals: %+v", d)) } } @@ -149,14 +149,14 @@ func (d *dirInodeOperations) Lookup(ctx context.Context, dir *fs.Inode, name str return fs.NewDirent(ctx, d.master, name), nil } - // Slave number? + // Replica number? n, err := strconv.ParseUint(name, 10, 32) if err != nil { // Not found. return nil, syserror.ENOENT } - s, ok := d.slaves[uint32(n)] + s, ok := d.replicas[uint32(n)] if !ok { return nil, syserror.ENOENT } @@ -236,7 +236,7 @@ func (d *dirInodeOperations) allocateTerminal(ctx context.Context) (*Terminal, e return nil, syserror.ENOMEM } - if _, ok := d.slaves[n]; ok { + if _, ok := d.replicas[n]; ok { panic(fmt.Sprintf("pty index collision; index %d already exists", n)) } @@ -244,19 +244,19 @@ func (d *dirInodeOperations) allocateTerminal(ctx context.Context) (*Terminal, e d.next++ // The reference returned by newTerminal is returned to the caller. - // Take another for the slave inode. + // Take another for the replica inode. t.IncRef() // Create a pts node. The owner is based on the context that opens // ptmx. creds := auth.CredentialsFromContext(ctx) uid, gid := creds.EffectiveKUID, creds.EffectiveKGID - slave := newSlaveInode(ctx, d, t, fs.FileOwner{uid, gid}, fs.FilePermsFromMode(0666)) + replica := newReplicaInode(ctx, d, t, fs.FileOwner{uid, gid}, fs.FilePermsFromMode(0666)) - d.slaves[n] = slave + d.replicas[n] = replica d.dentryMap.Add(strconv.FormatUint(uint64(n), 10), fs.DentAttr{ - Type: slave.StableAttr.Type, - InodeID: slave.StableAttr.InodeID, + Type: replica.StableAttr.Type, + InodeID: replica.StableAttr.InodeID, }) return t, nil @@ -267,18 +267,18 @@ func (d *dirInodeOperations) masterClose(ctx context.Context, t *Terminal) { d.mu.Lock() defer d.mu.Unlock() - // The slave end disappears from the directory when the master end is - // closed, even if the slave end is open elsewhere. + // The replica end disappears from the directory when the master end is + // closed, even if the replica end is open elsewhere. // // N.B. since we're using a backdoor method to remove a directory entry // we won't properly fire inotify events like Linux would. - s, ok := d.slaves[t.n] + s, ok := d.replicas[t.n] if !ok { panic(fmt.Sprintf("Terminal %+v doesn't exist in %+v?", t, d)) } s.DecRef(ctx) - delete(d.slaves, t.n) + delete(d.replicas, t.n) d.dentryMap.Remove(strconv.FormatUint(uint64(t.n), 10)) } diff --git a/pkg/sentry/fs/tty/fs.go b/pkg/sentry/fs/tty/fs.go index 2d4d44bf3..13f4901db 100644 --- a/pkg/sentry/fs/tty/fs.go +++ b/pkg/sentry/fs/tty/fs.go @@ -79,8 +79,8 @@ type superOperations struct{} // // It always returns true, forcing a Lookup for all entries. // -// Slave entries are dropped from dir when their master is closed, so an -// existing slave Dirent in the tree is not sufficient to guarantee that it +// Replica entries are dropped from dir when their master is closed, so an +// existing replica Dirent in the tree is not sufficient to guarantee that it // still exists on the filesystem. func (superOperations) Revalidate(context.Context, string, *fs.Inode, *fs.Inode) bool { return true diff --git a/pkg/sentry/fs/tty/line_discipline.go b/pkg/sentry/fs/tty/line_discipline.go index b6bc011a9..b34f4a0eb 100644 --- a/pkg/sentry/fs/tty/line_discipline.go +++ b/pkg/sentry/fs/tty/line_discipline.go @@ -44,7 +44,7 @@ const ( ) // lineDiscipline dictates how input and output are handled between the -// pseudoterminal (pty) master and slave. It can be configured to alter I/O, +// pseudoterminal (pty) master and replica. It can be configured to alter I/O, // modify control characters (e.g. Ctrl-C for SIGINT), etc. The following man // pages are good resources for how to affect the line discipline: // @@ -55,8 +55,8 @@ const ( // // lineDiscipline has a simple structure but supports a multitude of options // (see the above man pages). It consists of two queues of bytes: one from the -// terminal master to slave (the input queue) and one from slave to master (the -// output queue). When bytes are written to one end of the pty, the line +// terminal master to replica (the input queue) and one from replica to master +// (the output queue). When bytes are written to one end of the pty, the line // discipline reads the bytes, modifies them or takes special action if // required, and enqueues them to be read by the other end of the pty: // @@ -65,7 +65,7 @@ const ( // | (inputQueueWrite) +-------------+ (inputQueueRead) | // | | // | v -// masterFD slaveFD +// masterFD replicaFD // ^ | // | | // | output to terminal +--------------+ output from process | @@ -104,8 +104,8 @@ type lineDiscipline struct { // masterWaiter is used to wait on the master end of the TTY. masterWaiter waiter.Queue `state:"zerovalue"` - // slaveWaiter is used to wait on the slave end of the TTY. - slaveWaiter waiter.Queue `state:"zerovalue"` + // replicaWaiter is used to wait on the replica end of the TTY. + replicaWaiter waiter.Queue `state:"zerovalue"` } func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline { @@ -143,7 +143,7 @@ func (l *lineDiscipline) setTermios(task *kernel.Task, args arch.SyscallArgument l.inQueue.pushWaitBufLocked(l) l.inQueue.readable = true l.inQueue.mu.Unlock() - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) } return 0, err @@ -169,7 +169,7 @@ func (l *lineDiscipline) masterReadiness() waiter.EventMask { return l.inQueue.writeReadiness(&linux.MasterTermios) | l.outQueue.readReadiness(&linux.MasterTermios) } -func (l *lineDiscipline) slaveReadiness() waiter.EventMask { +func (l *lineDiscipline) replicaReadiness() waiter.EventMask { l.termiosMu.RLock() defer l.termiosMu.RUnlock() return l.outQueue.writeReadiness(&l.termios) | l.inQueue.readReadiness(&l.termios) @@ -189,7 +189,7 @@ func (l *lineDiscipline) inputQueueRead(ctx context.Context, dst usermem.IOSeque if n > 0 { l.masterWaiter.Notify(waiter.EventOut) if pushed { - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) } return n, nil } @@ -204,7 +204,7 @@ func (l *lineDiscipline) inputQueueWrite(ctx context.Context, src usermem.IOSequ return 0, err } if n > 0 { - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) return n, nil } return 0, syserror.ErrWouldBlock @@ -222,7 +222,7 @@ func (l *lineDiscipline) outputQueueRead(ctx context.Context, dst usermem.IOSequ return 0, err } if n > 0 { - l.slaveWaiter.Notify(waiter.EventOut) + l.replicaWaiter.Notify(waiter.EventOut) if pushed { l.masterWaiter.Notify(waiter.EventIn) } diff --git a/pkg/sentry/fs/tty/master.go b/pkg/sentry/fs/tty/master.go index 175457297..bebf90ffa 100644 --- a/pkg/sentry/fs/tty/master.go +++ b/pkg/sentry/fs/tty/master.go @@ -166,11 +166,11 @@ func (mf *masterFileOperations) Ioctl(ctx context.Context, _ *fs.File, io userme return 0, mf.t.ld.outputQueueReadSize(t, args) case linux.TCGETS: // N.B. TCGETS on the master actually returns the configuration - // of the slave end. + // of the replica end. return mf.t.ld.getTermios(t, args) case linux.TCSETS: // N.B. TCSETS on the master actually affects the configuration - // of the slave end. + // of the replica end. return mf.t.ld.setTermios(t, args) case linux.TCSETSW: // TODO(b/29356795): This should drain the output queue first. diff --git a/pkg/sentry/fs/tty/queue.go b/pkg/sentry/fs/tty/queue.go index f0a18c75a..e070a1b71 100644 --- a/pkg/sentry/fs/tty/queue.go +++ b/pkg/sentry/fs/tty/queue.go @@ -34,7 +34,7 @@ import ( const waitBufMaxBytes = 131072 // queue represents one of the input or output queues between a pty master and -// slave. Bytes written to a queue are added to the read buffer until it is +// replica. Bytes written to a queue are added to the read buffer until it is // full, at which point they are written to the wait buffer. Bytes are // processed (i.e. undergo termios transformations) as they are added to the // read buffer. The read buffer is readable when its length is nonzero and diff --git a/pkg/sentry/fs/tty/replica.go b/pkg/sentry/fs/tty/replica.go new file mode 100644 index 000000000..cb6cd6864 --- /dev/null +++ b/pkg/sentry/fs/tty/replica.go @@ -0,0 +1,186 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package tty + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" + "gvisor.dev/gvisor/tools/go_marshal/primitive" +) + +// LINT.IfChange + +// replicaInodeOperations are the fs.InodeOperations for the replica end of the +// Terminal (pts file). +// +// +stateify savable +type replicaInodeOperations struct { + fsutil.SimpleFileInode + + // d is the containing dir. + d *dirInodeOperations + + // t is the connected Terminal. + t *Terminal +} + +var _ fs.InodeOperations = (*replicaInodeOperations)(nil) + +// newReplicaInode creates an fs.Inode for the replica end of a terminal. +// +// newReplicaInode takes ownership of t. +func newReplicaInode(ctx context.Context, d *dirInodeOperations, t *Terminal, owner fs.FileOwner, p fs.FilePermissions) *fs.Inode { + iops := &replicaInodeOperations{ + SimpleFileInode: *fsutil.NewSimpleFileInode(ctx, owner, p, linux.DEVPTS_SUPER_MAGIC), + d: d, + t: t, + } + + return fs.NewInode(ctx, iops, d.msrc, fs.StableAttr{ + DeviceID: ptsDevice.DeviceID(), + // N.B. Linux always uses inode id = tty index + 3. See + // fs/devpts/inode.c:devpts_pty_new. + // + // TODO(b/75267214): Since ptsDevice must be shared between + // different mounts, we must not assign fixed numbers. + InodeID: ptsDevice.NextIno(), + Type: fs.CharacterDevice, + // See fs/devpts/inode.c:devpts_fill_super. + BlockSize: 1024, + DeviceFileMajor: linux.UNIX98_PTY_REPLICA_MAJOR, + DeviceFileMinor: t.n, + }) +} + +// Release implements fs.InodeOperations.Release. +func (si *replicaInodeOperations) Release(ctx context.Context) { + si.t.DecRef(ctx) +} + +// Truncate implements fs.InodeOperations.Truncate. +func (*replicaInodeOperations) Truncate(context.Context, *fs.Inode, int64) error { + return nil +} + +// GetFile implements fs.InodeOperations.GetFile. +// +// This may race with destruction of the terminal. If the terminal is gone, it +// returns ENOENT. +func (si *replicaInodeOperations) GetFile(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) (*fs.File, error) { + return fs.NewFile(ctx, d, flags, &replicaFileOperations{si: si}), nil +} + +// replicaFileOperations are the fs.FileOperations for the replica end of a +// terminal. +// +// +stateify savable +type replicaFileOperations struct { + fsutil.FilePipeSeek `state:"nosave"` + fsutil.FileNotDirReaddir `state:"nosave"` + fsutil.FileNoFsync `state:"nosave"` + fsutil.FileNoMMap `state:"nosave"` + fsutil.FileNoSplice `state:"nosave"` + fsutil.FileNoopFlush `state:"nosave"` + fsutil.FileUseInodeUnstableAttr `state:"nosave"` + + // si is the inode operations. + si *replicaInodeOperations +} + +var _ fs.FileOperations = (*replicaFileOperations)(nil) + +// Release implements fs.FileOperations.Release. +func (sf *replicaFileOperations) Release(context.Context) { +} + +// EventRegister implements waiter.Waitable.EventRegister. +func (sf *replicaFileOperations) EventRegister(e *waiter.Entry, mask waiter.EventMask) { + sf.si.t.ld.replicaWaiter.EventRegister(e, mask) +} + +// EventUnregister implements waiter.Waitable.EventUnregister. +func (sf *replicaFileOperations) EventUnregister(e *waiter.Entry) { + sf.si.t.ld.replicaWaiter.EventUnregister(e) +} + +// Readiness implements waiter.Waitable.Readiness. +func (sf *replicaFileOperations) Readiness(mask waiter.EventMask) waiter.EventMask { + return sf.si.t.ld.replicaReadiness() +} + +// Read implements fs.FileOperations.Read. +func (sf *replicaFileOperations) Read(ctx context.Context, _ *fs.File, dst usermem.IOSequence, _ int64) (int64, error) { + return sf.si.t.ld.inputQueueRead(ctx, dst) +} + +// Write implements fs.FileOperations.Write. +func (sf *replicaFileOperations) Write(ctx context.Context, _ *fs.File, src usermem.IOSequence, _ int64) (int64, error) { + return sf.si.t.ld.outputQueueWrite(ctx, src) +} + +// Ioctl implements fs.FileOperations.Ioctl. +func (sf *replicaFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { + t := kernel.TaskFromContext(ctx) + if t == nil { + // ioctl(2) may only be called from a task goroutine. + return 0, syserror.ENOTTY + } + + switch cmd := args[1].Uint(); cmd { + case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ + // Get the number of bytes in the input queue read buffer. + return 0, sf.si.t.ld.inputQueueReadSize(t, args) + case linux.TCGETS: + return sf.si.t.ld.getTermios(t, args) + case linux.TCSETS: + return sf.si.t.ld.setTermios(t, args) + case linux.TCSETSW: + // TODO(b/29356795): This should drain the output queue first. + return sf.si.t.ld.setTermios(t, args) + case linux.TIOCGPTN: + nP := primitive.Uint32(sf.si.t.n) + _, err := nP.CopyOut(t, args[2].Pointer()) + return 0, err + case linux.TIOCGWINSZ: + return 0, sf.si.t.ld.windowSize(t, args) + case linux.TIOCSWINSZ: + return 0, sf.si.t.ld.setWindowSize(t, args) + case linux.TIOCSCTTY: + // Make the given terminal the controlling terminal of the + // calling process. + return 0, sf.si.t.setControllingTTY(ctx, args, false /* isMaster */) + case linux.TIOCNOTTY: + // Release this process's controlling terminal. + return 0, sf.si.t.releaseControllingTTY(ctx, args, false /* isMaster */) + case linux.TIOCGPGRP: + // Get the foreground process group. + return sf.si.t.foregroundProcessGroup(ctx, args, false /* isMaster */) + case linux.TIOCSPGRP: + // Set the foreground process group. + return sf.si.t.setForegroundProcessGroup(ctx, args, false /* isMaster */) + default: + maybeEmitUnimplementedEvent(ctx, cmd) + return 0, syserror.ENOTTY + } +} + +// LINT.ThenChange(../../fsimpl/devpts/replica.go) diff --git a/pkg/sentry/fs/tty/slave.go b/pkg/sentry/fs/tty/slave.go deleted file mode 100644 index 933d2c3ff..000000000 --- a/pkg/sentry/fs/tty/slave.go +++ /dev/null @@ -1,185 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package tty - -import ( - "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/context" - "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/fs" - "gvisor.dev/gvisor/pkg/sentry/fs/fsutil" - "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/syserror" - "gvisor.dev/gvisor/pkg/usermem" - "gvisor.dev/gvisor/pkg/waiter" - "gvisor.dev/gvisor/tools/go_marshal/primitive" -) - -// LINT.IfChange - -// slaveInodeOperations are the fs.InodeOperations for the slave end of the -// Terminal (pts file). -// -// +stateify savable -type slaveInodeOperations struct { - fsutil.SimpleFileInode - - // d is the containing dir. - d *dirInodeOperations - - // t is the connected Terminal. - t *Terminal -} - -var _ fs.InodeOperations = (*slaveInodeOperations)(nil) - -// newSlaveInode creates an fs.Inode for the slave end of a terminal. -// -// newSlaveInode takes ownership of t. -func newSlaveInode(ctx context.Context, d *dirInodeOperations, t *Terminal, owner fs.FileOwner, p fs.FilePermissions) *fs.Inode { - iops := &slaveInodeOperations{ - SimpleFileInode: *fsutil.NewSimpleFileInode(ctx, owner, p, linux.DEVPTS_SUPER_MAGIC), - d: d, - t: t, - } - - return fs.NewInode(ctx, iops, d.msrc, fs.StableAttr{ - DeviceID: ptsDevice.DeviceID(), - // N.B. Linux always uses inode id = tty index + 3. See - // fs/devpts/inode.c:devpts_pty_new. - // - // TODO(b/75267214): Since ptsDevice must be shared between - // different mounts, we must not assign fixed numbers. - InodeID: ptsDevice.NextIno(), - Type: fs.CharacterDevice, - // See fs/devpts/inode.c:devpts_fill_super. - BlockSize: 1024, - DeviceFileMajor: linux.UNIX98_PTY_SLAVE_MAJOR, - DeviceFileMinor: t.n, - }) -} - -// Release implements fs.InodeOperations.Release. -func (si *slaveInodeOperations) Release(ctx context.Context) { - si.t.DecRef(ctx) -} - -// Truncate implements fs.InodeOperations.Truncate. -func (*slaveInodeOperations) Truncate(context.Context, *fs.Inode, int64) error { - return nil -} - -// GetFile implements fs.InodeOperations.GetFile. -// -// This may race with destruction of the terminal. If the terminal is gone, it -// returns ENOENT. -func (si *slaveInodeOperations) GetFile(ctx context.Context, d *fs.Dirent, flags fs.FileFlags) (*fs.File, error) { - return fs.NewFile(ctx, d, flags, &slaveFileOperations{si: si}), nil -} - -// slaveFileOperations are the fs.FileOperations for the slave end of a terminal. -// -// +stateify savable -type slaveFileOperations struct { - fsutil.FilePipeSeek `state:"nosave"` - fsutil.FileNotDirReaddir `state:"nosave"` - fsutil.FileNoFsync `state:"nosave"` - fsutil.FileNoMMap `state:"nosave"` - fsutil.FileNoSplice `state:"nosave"` - fsutil.FileNoopFlush `state:"nosave"` - fsutil.FileUseInodeUnstableAttr `state:"nosave"` - - // si is the inode operations. - si *slaveInodeOperations -} - -var _ fs.FileOperations = (*slaveFileOperations)(nil) - -// Release implements fs.FileOperations.Release. -func (sf *slaveFileOperations) Release(context.Context) { -} - -// EventRegister implements waiter.Waitable.EventRegister. -func (sf *slaveFileOperations) EventRegister(e *waiter.Entry, mask waiter.EventMask) { - sf.si.t.ld.slaveWaiter.EventRegister(e, mask) -} - -// EventUnregister implements waiter.Waitable.EventUnregister. -func (sf *slaveFileOperations) EventUnregister(e *waiter.Entry) { - sf.si.t.ld.slaveWaiter.EventUnregister(e) -} - -// Readiness implements waiter.Waitable.Readiness. -func (sf *slaveFileOperations) Readiness(mask waiter.EventMask) waiter.EventMask { - return sf.si.t.ld.slaveReadiness() -} - -// Read implements fs.FileOperations.Read. -func (sf *slaveFileOperations) Read(ctx context.Context, _ *fs.File, dst usermem.IOSequence, _ int64) (int64, error) { - return sf.si.t.ld.inputQueueRead(ctx, dst) -} - -// Write implements fs.FileOperations.Write. -func (sf *slaveFileOperations) Write(ctx context.Context, _ *fs.File, src usermem.IOSequence, _ int64) (int64, error) { - return sf.si.t.ld.outputQueueWrite(ctx, src) -} - -// Ioctl implements fs.FileOperations.Ioctl. -func (sf *slaveFileOperations) Ioctl(ctx context.Context, _ *fs.File, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { - t := kernel.TaskFromContext(ctx) - if t == nil { - // ioctl(2) may only be called from a task goroutine. - return 0, syserror.ENOTTY - } - - switch cmd := args[1].Uint(); cmd { - case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ - // Get the number of bytes in the input queue read buffer. - return 0, sf.si.t.ld.inputQueueReadSize(t, args) - case linux.TCGETS: - return sf.si.t.ld.getTermios(t, args) - case linux.TCSETS: - return sf.si.t.ld.setTermios(t, args) - case linux.TCSETSW: - // TODO(b/29356795): This should drain the output queue first. - return sf.si.t.ld.setTermios(t, args) - case linux.TIOCGPTN: - nP := primitive.Uint32(sf.si.t.n) - _, err := nP.CopyOut(t, args[2].Pointer()) - return 0, err - case linux.TIOCGWINSZ: - return 0, sf.si.t.ld.windowSize(t, args) - case linux.TIOCSWINSZ: - return 0, sf.si.t.ld.setWindowSize(t, args) - case linux.TIOCSCTTY: - // Make the given terminal the controlling terminal of the - // calling process. - return 0, sf.si.t.setControllingTTY(ctx, args, false /* isMaster */) - case linux.TIOCNOTTY: - // Release this process's controlling terminal. - return 0, sf.si.t.releaseControllingTTY(ctx, args, false /* isMaster */) - case linux.TIOCGPGRP: - // Get the foreground process group. - return sf.si.t.foregroundProcessGroup(ctx, args, false /* isMaster */) - case linux.TIOCSPGRP: - // Set the foreground process group. - return sf.si.t.setForegroundProcessGroup(ctx, args, false /* isMaster */) - default: - maybeEmitUnimplementedEvent(ctx, cmd) - return 0, syserror.ENOTTY - } -} - -// LINT.ThenChange(../../fsimpl/devpts/slave.go) diff --git a/pkg/sentry/fs/tty/terminal.go b/pkg/sentry/fs/tty/terminal.go index 56b59632d..c9dbf1f3b 100644 --- a/pkg/sentry/fs/tty/terminal.go +++ b/pkg/sentry/fs/tty/terminal.go @@ -44,19 +44,19 @@ type Terminal struct { // this terminal. This field is immutable. masterKTTY *kernel.TTY - // slaveKTTY contains the controlling process of the slave end of this + // replicaKTTY contains the controlling process of the replica end of this // terminal. This field is immutable. - slaveKTTY *kernel.TTY + replicaKTTY *kernel.TTY } func newTerminal(ctx context.Context, d *dirInodeOperations, n uint32) *Terminal { - termios := linux.DefaultSlaveTermios + termios := linux.DefaultReplicaTermios t := Terminal{ - d: d, - n: n, - ld: newLineDiscipline(termios), - masterKTTY: &kernel.TTY{Index: n}, - slaveKTTY: &kernel.TTY{Index: n}, + d: d, + n: n, + ld: newLineDiscipline(termios), + masterKTTY: &kernel.TTY{Index: n}, + replicaKTTY: &kernel.TTY{Index: n}, } t.EnableLeakCheck("tty.Terminal") return &t @@ -123,7 +123,7 @@ func (tm *Terminal) tty(isMaster bool) *kernel.TTY { if isMaster { return tm.masterKTTY } - return tm.slaveKTTY + return tm.replicaKTTY } // LINT.ThenChange(../../fsimpl/devpts/terminal.go) diff --git a/pkg/sentry/fs/tty/tty_test.go b/pkg/sentry/fs/tty/tty_test.go index 2cbc05678..49edee83d 100644 --- a/pkg/sentry/fs/tty/tty_test.go +++ b/pkg/sentry/fs/tty/tty_test.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/usermem" ) -func TestSimpleMasterToSlave(t *testing.T) { - ld := newLineDiscipline(linux.DefaultSlaveTermios) +func TestSimpleMasterToReplica(t *testing.T) { + ld := newLineDiscipline(linux.DefaultReplicaTermios) ctx := contexttest.Context(t) inBytes := []byte("hello, tty\n") src := usermem.BytesIOSequence(inBytes) diff --git a/pkg/sentry/fsimpl/devpts/BUILD b/pkg/sentry/fsimpl/devpts/BUILD index 3e8c5e3fd..ac48ab34b 100644 --- a/pkg/sentry/fsimpl/devpts/BUILD +++ b/pkg/sentry/fsimpl/devpts/BUILD @@ -21,8 +21,8 @@ go_library( "line_discipline.go", "master.go", "queue.go", + "replica.go", "root_inode_refs.go", - "slave.go", "terminal.go", ], visibility = ["//pkg/sentry:internal"], diff --git a/pkg/sentry/fsimpl/devpts/devpts.go b/pkg/sentry/fsimpl/devpts/devpts.go index 57580f4d4..dcf1ee25b 100644 --- a/pkg/sentry/fsimpl/devpts/devpts.go +++ b/pkg/sentry/fsimpl/devpts/devpts.go @@ -79,7 +79,7 @@ func (fstype FilesystemType) newFilesystem(vfsObj *vfs.VirtualFilesystem, creds // Construct the root directory. This is always inode id 1. root := &rootInode{ - slaves: make(map[uint32]*slaveInode), + replicas: make(map[uint32]*replicaInode), } root.InodeAttrs.Init(creds, linux.UNNAMED_MAJOR, devMinor, 1, linux.ModeDirectory|0555) root.OrderedChildren.Init(kernfs.OrderedChildrenOptions{}) @@ -133,8 +133,8 @@ type rootInode struct { // mu protects the fields below. mu sync.Mutex - // slaves maps pty ids to slave inodes. - slaves map[uint32]*slaveInode + // replicas maps pty ids to replica inodes. + replicas map[uint32]*replicaInode // nextIdx is the next pty index to use. Must be accessed atomically. // @@ -154,22 +154,22 @@ func (i *rootInode) allocateTerminal(creds *auth.Credentials) (*Terminal, error) idx := i.nextIdx i.nextIdx++ - // Sanity check that slave with idx does not exist. - if _, ok := i.slaves[idx]; ok { + // Sanity check that replica with idx does not exist. + if _, ok := i.replicas[idx]; ok { panic(fmt.Sprintf("pty index collision; index %d already exists", idx)) } - // Create the new terminal and slave. + // Create the new terminal and replica. t := newTerminal(idx) - slave := &slaveInode{ + replica := &replicaInode{ root: i, t: t, } // Linux always uses pty index + 3 as the inode id. See // fs/devpts/inode.c:devpts_pty_new(). - slave.InodeAttrs.Init(creds, i.InodeAttrs.DevMajor(), i.InodeAttrs.DevMinor(), uint64(idx+3), linux.ModeCharacterDevice|0600) - slave.dentry.Init(slave) - i.slaves[idx] = slave + replica.InodeAttrs.Init(creds, i.InodeAttrs.DevMajor(), i.InodeAttrs.DevMinor(), uint64(idx+3), linux.ModeCharacterDevice|0600) + replica.dentry.Init(replica) + i.replicas[idx] = replica return t, nil } @@ -179,11 +179,11 @@ func (i *rootInode) masterClose(t *Terminal) { i.mu.Lock() defer i.mu.Unlock() - // Sanity check that slave with idx exists. - if _, ok := i.slaves[t.n]; !ok { + // Sanity check that replica with idx exists. + if _, ok := i.replicas[t.n]; !ok { panic(fmt.Sprintf("pty with index %d does not exist", t.n)) } - delete(i.slaves, t.n) + delete(i.replicas, t.n) } // Open implements kernfs.Inode.Open. @@ -205,7 +205,7 @@ func (i *rootInode) Lookup(ctx context.Context, name string) (*vfs.Dentry, error } i.mu.Lock() defer i.mu.Unlock() - if si, ok := i.slaves[uint32(idx)]; ok { + if si, ok := i.replicas[uint32(idx)]; ok { si.dentry.IncRef() return si.dentry.VFSDentry(), nil @@ -217,8 +217,8 @@ func (i *rootInode) Lookup(ctx context.Context, name string) (*vfs.Dentry, error func (i *rootInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, offset, relOffset int64) (int64, error) { i.mu.Lock() defer i.mu.Unlock() - ids := make([]int, 0, len(i.slaves)) - for id := range i.slaves { + ids := make([]int, 0, len(i.replicas)) + for id := range i.replicas { ids = append(ids, int(id)) } sort.Ints(ids) @@ -226,7 +226,7 @@ func (i *rootInode) IterDirents(ctx context.Context, cb vfs.IterDirentsCallback, dirent := vfs.Dirent{ Name: strconv.FormatUint(uint64(id), 10), Type: linux.DT_CHR, - Ino: i.slaves[uint32(id)].InodeAttrs.Ino(), + Ino: i.replicas[uint32(id)].InodeAttrs.Ino(), NextOff: offset + 1, } if err := cb.Handle(dirent); err != nil { diff --git a/pkg/sentry/fsimpl/devpts/devpts_test.go b/pkg/sentry/fsimpl/devpts/devpts_test.go index b7c149047..448390cfe 100644 --- a/pkg/sentry/fsimpl/devpts/devpts_test.go +++ b/pkg/sentry/fsimpl/devpts/devpts_test.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/usermem" ) -func TestSimpleMasterToSlave(t *testing.T) { - ld := newLineDiscipline(linux.DefaultSlaveTermios) +func TestSimpleMasterToReplica(t *testing.T) { + ld := newLineDiscipline(linux.DefaultReplicaTermios) ctx := contexttest.Context(t) inBytes := []byte("hello, tty\n") src := usermem.BytesIOSequence(inBytes) diff --git a/pkg/sentry/fsimpl/devpts/line_discipline.go b/pkg/sentry/fsimpl/devpts/line_discipline.go index b954c1ba1..e6b0e81cf 100644 --- a/pkg/sentry/fsimpl/devpts/line_discipline.go +++ b/pkg/sentry/fsimpl/devpts/line_discipline.go @@ -42,7 +42,7 @@ const ( ) // lineDiscipline dictates how input and output are handled between the -// pseudoterminal (pty) master and slave. It can be configured to alter I/O, +// pseudoterminal (pty) master and replica. It can be configured to alter I/O, // modify control characters (e.g. Ctrl-C for SIGINT), etc. The following man // pages are good resources for how to affect the line discipline: // @@ -53,8 +53,8 @@ const ( // // lineDiscipline has a simple structure but supports a multitude of options // (see the above man pages). It consists of two queues of bytes: one from the -// terminal master to slave (the input queue) and one from slave to master (the -// output queue). When bytes are written to one end of the pty, the line +// terminal master to replica (the input queue) and one from replica to master +// (the output queue). When bytes are written to one end of the pty, the line // discipline reads the bytes, modifies them or takes special action if // required, and enqueues them to be read by the other end of the pty: // @@ -63,7 +63,7 @@ const ( // | (inputQueueWrite) +-------------+ (inputQueueRead) | // | | // | v -// masterFD slaveFD +// masterFD replicaFD // ^ | // | | // | output to terminal +--------------+ output from process | @@ -102,8 +102,8 @@ type lineDiscipline struct { // masterWaiter is used to wait on the master end of the TTY. masterWaiter waiter.Queue `state:"zerovalue"` - // slaveWaiter is used to wait on the slave end of the TTY. - slaveWaiter waiter.Queue `state:"zerovalue"` + // replicaWaiter is used to wait on the replica end of the TTY. + replicaWaiter waiter.Queue `state:"zerovalue"` } func newLineDiscipline(termios linux.KernelTermios) *lineDiscipline { @@ -141,7 +141,7 @@ func (l *lineDiscipline) setTermios(task *kernel.Task, args arch.SyscallArgument l.inQueue.pushWaitBufLocked(l) l.inQueue.readable = true l.inQueue.mu.Unlock() - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) } return 0, err @@ -167,7 +167,7 @@ func (l *lineDiscipline) masterReadiness() waiter.EventMask { return l.inQueue.writeReadiness(&linux.MasterTermios) | l.outQueue.readReadiness(&linux.MasterTermios) } -func (l *lineDiscipline) slaveReadiness() waiter.EventMask { +func (l *lineDiscipline) replicaReadiness() waiter.EventMask { l.termiosMu.RLock() defer l.termiosMu.RUnlock() return l.outQueue.writeReadiness(&l.termios) | l.inQueue.readReadiness(&l.termios) @@ -187,7 +187,7 @@ func (l *lineDiscipline) inputQueueRead(ctx context.Context, dst usermem.IOSeque if n > 0 { l.masterWaiter.Notify(waiter.EventOut) if pushed { - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) } return n, nil } @@ -202,7 +202,7 @@ func (l *lineDiscipline) inputQueueWrite(ctx context.Context, src usermem.IOSequ return 0, err } if n > 0 { - l.slaveWaiter.Notify(waiter.EventIn) + l.replicaWaiter.Notify(waiter.EventIn) return n, nil } return 0, syserror.ErrWouldBlock @@ -220,7 +220,7 @@ func (l *lineDiscipline) outputQueueRead(ctx context.Context, dst usermem.IOSequ return 0, err } if n > 0 { - l.slaveWaiter.Notify(waiter.EventOut) + l.replicaWaiter.Notify(waiter.EventOut) if pushed { l.masterWaiter.Notify(waiter.EventIn) } diff --git a/pkg/sentry/fsimpl/devpts/master.go b/pkg/sentry/fsimpl/devpts/master.go index 3422db6a4..d07e1ded8 100644 --- a/pkg/sentry/fsimpl/devpts/master.go +++ b/pkg/sentry/fsimpl/devpts/master.go @@ -145,11 +145,11 @@ func (mfd *masterFileDescription) Ioctl(ctx context.Context, io usermem.IO, args return 0, mfd.t.ld.outputQueueReadSize(t, io, args) case linux.TCGETS: // N.B. TCGETS on the master actually returns the configuration - // of the slave end. + // of the replica end. return mfd.t.ld.getTermios(t, args) case linux.TCSETS: // N.B. TCSETS on the master actually affects the configuration - // of the slave end. + // of the replica end. return mfd.t.ld.setTermios(t, args) case linux.TCSETSW: // TODO(b/29356795): This should drain the output queue first. diff --git a/pkg/sentry/fsimpl/devpts/queue.go b/pkg/sentry/fsimpl/devpts/queue.go index 08eca2589..ca36b66e9 100644 --- a/pkg/sentry/fsimpl/devpts/queue.go +++ b/pkg/sentry/fsimpl/devpts/queue.go @@ -32,7 +32,7 @@ import ( const waitBufMaxBytes = 131072 // queue represents one of the input or output queues between a pty master and -// slave. Bytes written to a queue are added to the read buffer until it is +// replica. Bytes written to a queue are added to the read buffer until it is // full, at which point they are written to the wait buffer. Bytes are // processed (i.e. undergo termios transformations) as they are added to the // read buffer. The read buffer is readable when its length is nonzero and diff --git a/pkg/sentry/fsimpl/devpts/replica.go b/pkg/sentry/fsimpl/devpts/replica.go new file mode 100644 index 000000000..1f99f4b4d --- /dev/null +++ b/pkg/sentry/fsimpl/devpts/replica.go @@ -0,0 +1,205 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package devpts + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/arch" + fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" + "gvisor.dev/gvisor/tools/go_marshal/primitive" +) + +// replicaInode is the inode for the replica end of the Terminal. +type replicaInode struct { + implStatFS + kernfs.InodeAttrs + kernfs.InodeNoopRefCount + kernfs.InodeNotDirectory + kernfs.InodeNotSymlink + + locks vfs.FileLocks + + // Keep a reference to this inode's dentry. + dentry kernfs.Dentry + + // root is the devpts root inode. + root *rootInode + + // t is the connected Terminal. + t *Terminal +} + +var _ kernfs.Inode = (*replicaInode)(nil) + +// Open implements kernfs.Inode.Open. +func (si *replicaInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { + si.IncRef() + fd := &replicaFileDescription{ + inode: si, + } + fd.LockFD.Init(&si.locks) + if err := fd.vfsfd.Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { + si.DecRef(ctx) + return nil, err + } + return &fd.vfsfd, nil + +} + +// Valid implements kernfs.Inode.Valid. +func (si *replicaInode) Valid(context.Context) bool { + // Return valid if the replica still exists. + si.root.mu.Lock() + defer si.root.mu.Unlock() + _, ok := si.root.replicas[si.t.n] + return ok +} + +// Stat implements kernfs.Inode.Stat. +func (si *replicaInode) Stat(ctx context.Context, vfsfs *vfs.Filesystem, opts vfs.StatOptions) (linux.Statx, error) { + statx, err := si.InodeAttrs.Stat(ctx, vfsfs, opts) + if err != nil { + return linux.Statx{}, err + } + statx.Blksize = 1024 + statx.RdevMajor = linux.UNIX98_PTY_REPLICA_MAJOR + statx.RdevMinor = si.t.n + return statx, nil +} + +// SetStat implements kernfs.Inode.SetStat +func (si *replicaInode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { + if opts.Stat.Mask&linux.STATX_SIZE != 0 { + return syserror.EINVAL + } + return si.InodeAttrs.SetStat(ctx, vfsfs, creds, opts) +} + +type replicaFileDescription struct { + vfsfd vfs.FileDescription + vfs.FileDescriptionDefaultImpl + vfs.LockFD + + inode *replicaInode +} + +var _ vfs.FileDescriptionImpl = (*replicaFileDescription)(nil) + +// Release implements fs.FileOperations.Release. +func (sfd *replicaFileDescription) Release(ctx context.Context) { + sfd.inode.DecRef(ctx) +} + +// EventRegister implements waiter.Waitable.EventRegister. +func (sfd *replicaFileDescription) EventRegister(e *waiter.Entry, mask waiter.EventMask) { + sfd.inode.t.ld.replicaWaiter.EventRegister(e, mask) +} + +// EventUnregister implements waiter.Waitable.EventUnregister. +func (sfd *replicaFileDescription) EventUnregister(e *waiter.Entry) { + sfd.inode.t.ld.replicaWaiter.EventUnregister(e) +} + +// Readiness implements waiter.Waitable.Readiness. +func (sfd *replicaFileDescription) Readiness(mask waiter.EventMask) waiter.EventMask { + return sfd.inode.t.ld.replicaReadiness() +} + +// Read implements vfs.FileDescriptionImpl.Read. +func (sfd *replicaFileDescription) Read(ctx context.Context, dst usermem.IOSequence, _ vfs.ReadOptions) (int64, error) { + return sfd.inode.t.ld.inputQueueRead(ctx, dst) +} + +// Write implements vfs.FileDescriptionImpl.Write. +func (sfd *replicaFileDescription) Write(ctx context.Context, src usermem.IOSequence, _ vfs.WriteOptions) (int64, error) { + return sfd.inode.t.ld.outputQueueWrite(ctx, src) +} + +// Ioctl implements vfs.FileDescriptionImpl.Ioctl. +func (sfd *replicaFileDescription) Ioctl(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { + t := kernel.TaskFromContext(ctx) + if t == nil { + // ioctl(2) may only be called from a task goroutine. + return 0, syserror.ENOTTY + } + + switch cmd := args[1].Uint(); cmd { + case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ + // Get the number of bytes in the input queue read buffer. + return 0, sfd.inode.t.ld.inputQueueReadSize(t, io, args) + case linux.TCGETS: + return sfd.inode.t.ld.getTermios(t, args) + case linux.TCSETS: + return sfd.inode.t.ld.setTermios(t, args) + case linux.TCSETSW: + // TODO(b/29356795): This should drain the output queue first. + return sfd.inode.t.ld.setTermios(t, args) + case linux.TIOCGPTN: + nP := primitive.Uint32(sfd.inode.t.n) + _, err := nP.CopyOut(t, args[2].Pointer()) + return 0, err + case linux.TIOCGWINSZ: + return 0, sfd.inode.t.ld.windowSize(t, args) + case linux.TIOCSWINSZ: + return 0, sfd.inode.t.ld.setWindowSize(t, args) + case linux.TIOCSCTTY: + // Make the given terminal the controlling terminal of the + // calling process. + return 0, sfd.inode.t.setControllingTTY(ctx, args, false /* isMaster */) + case linux.TIOCNOTTY: + // Release this process's controlling terminal. + return 0, sfd.inode.t.releaseControllingTTY(ctx, args, false /* isMaster */) + case linux.TIOCGPGRP: + // Get the foreground process group. + return sfd.inode.t.foregroundProcessGroup(ctx, args, false /* isMaster */) + case linux.TIOCSPGRP: + // Set the foreground process group. + return sfd.inode.t.setForegroundProcessGroup(ctx, args, false /* isMaster */) + default: + maybeEmitUnimplementedEvent(ctx, cmd) + return 0, syserror.ENOTTY + } +} + +// SetStat implements vfs.FileDescriptionImpl.SetStat. +func (sfd *replicaFileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { + creds := auth.CredentialsFromContext(ctx) + fs := sfd.vfsfd.VirtualDentry().Mount().Filesystem() + return sfd.inode.SetStat(ctx, fs, creds, opts) +} + +// Stat implements vfs.FileDescriptionImpl.Stat. +func (sfd *replicaFileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linux.Statx, error) { + fs := sfd.vfsfd.VirtualDentry().Mount().Filesystem() + return sfd.inode.Stat(ctx, fs, opts) +} + +// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. +func (sfd *replicaFileDescription) LockPOSIX(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, start, length uint64, whence int16, block fslock.Blocker) error { + return sfd.Locks().LockPOSIX(ctx, &sfd.vfsfd, uid, t, start, length, whence, block) +} + +// UnlockPOSIX implements vfs.FileDescriptionImpl.UnlockPOSIX. +func (sfd *replicaFileDescription) UnlockPOSIX(ctx context.Context, uid fslock.UniqueID, start, length uint64, whence int16) error { + return sfd.Locks().UnlockPOSIX(ctx, &sfd.vfsfd, uid, start, length, whence) +} diff --git a/pkg/sentry/fsimpl/devpts/slave.go b/pkg/sentry/fsimpl/devpts/slave.go deleted file mode 100644 index 5f4b474b3..000000000 --- a/pkg/sentry/fsimpl/devpts/slave.go +++ /dev/null @@ -1,205 +0,0 @@ -// Copyright 2020 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package devpts - -import ( - "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/context" - "gvisor.dev/gvisor/pkg/sentry/arch" - fslock "gvisor.dev/gvisor/pkg/sentry/fs/lock" - "gvisor.dev/gvisor/pkg/sentry/fsimpl/kernfs" - "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/vfs" - "gvisor.dev/gvisor/pkg/syserror" - "gvisor.dev/gvisor/pkg/usermem" - "gvisor.dev/gvisor/pkg/waiter" - "gvisor.dev/gvisor/tools/go_marshal/primitive" -) - -// slaveInode is the inode for the slave end of the Terminal. -type slaveInode struct { - implStatFS - kernfs.InodeAttrs - kernfs.InodeNoopRefCount - kernfs.InodeNotDirectory - kernfs.InodeNotSymlink - - locks vfs.FileLocks - - // Keep a reference to this inode's dentry. - dentry kernfs.Dentry - - // root is the devpts root inode. - root *rootInode - - // t is the connected Terminal. - t *Terminal -} - -var _ kernfs.Inode = (*slaveInode)(nil) - -// Open implements kernfs.Inode.Open. -func (si *slaveInode) Open(ctx context.Context, rp *vfs.ResolvingPath, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { - si.IncRef() - fd := &slaveFileDescription{ - inode: si, - } - fd.LockFD.Init(&si.locks) - if err := fd.vfsfd.Init(fd, opts.Flags, rp.Mount(), vfsd, &vfs.FileDescriptionOptions{}); err != nil { - si.DecRef(ctx) - return nil, err - } - return &fd.vfsfd, nil - -} - -// Valid implements kernfs.Inode.Valid. -func (si *slaveInode) Valid(context.Context) bool { - // Return valid if the slave still exists. - si.root.mu.Lock() - defer si.root.mu.Unlock() - _, ok := si.root.slaves[si.t.n] - return ok -} - -// Stat implements kernfs.Inode.Stat. -func (si *slaveInode) Stat(ctx context.Context, vfsfs *vfs.Filesystem, opts vfs.StatOptions) (linux.Statx, error) { - statx, err := si.InodeAttrs.Stat(ctx, vfsfs, opts) - if err != nil { - return linux.Statx{}, err - } - statx.Blksize = 1024 - statx.RdevMajor = linux.UNIX98_PTY_SLAVE_MAJOR - statx.RdevMinor = si.t.n - return statx, nil -} - -// SetStat implements kernfs.Inode.SetStat -func (si *slaveInode) SetStat(ctx context.Context, vfsfs *vfs.Filesystem, creds *auth.Credentials, opts vfs.SetStatOptions) error { - if opts.Stat.Mask&linux.STATX_SIZE != 0 { - return syserror.EINVAL - } - return si.InodeAttrs.SetStat(ctx, vfsfs, creds, opts) -} - -type slaveFileDescription struct { - vfsfd vfs.FileDescription - vfs.FileDescriptionDefaultImpl - vfs.LockFD - - inode *slaveInode -} - -var _ vfs.FileDescriptionImpl = (*slaveFileDescription)(nil) - -// Release implements fs.FileOperations.Release. -func (sfd *slaveFileDescription) Release(ctx context.Context) { - sfd.inode.DecRef(ctx) -} - -// EventRegister implements waiter.Waitable.EventRegister. -func (sfd *slaveFileDescription) EventRegister(e *waiter.Entry, mask waiter.EventMask) { - sfd.inode.t.ld.slaveWaiter.EventRegister(e, mask) -} - -// EventUnregister implements waiter.Waitable.EventUnregister. -func (sfd *slaveFileDescription) EventUnregister(e *waiter.Entry) { - sfd.inode.t.ld.slaveWaiter.EventUnregister(e) -} - -// Readiness implements waiter.Waitable.Readiness. -func (sfd *slaveFileDescription) Readiness(mask waiter.EventMask) waiter.EventMask { - return sfd.inode.t.ld.slaveReadiness() -} - -// Read implements vfs.FileDescriptionImpl.Read. -func (sfd *slaveFileDescription) Read(ctx context.Context, dst usermem.IOSequence, _ vfs.ReadOptions) (int64, error) { - return sfd.inode.t.ld.inputQueueRead(ctx, dst) -} - -// Write implements vfs.FileDescriptionImpl.Write. -func (sfd *slaveFileDescription) Write(ctx context.Context, src usermem.IOSequence, _ vfs.WriteOptions) (int64, error) { - return sfd.inode.t.ld.outputQueueWrite(ctx, src) -} - -// Ioctl implements vfs.FileDescriptionImpl.Ioctl. -func (sfd *slaveFileDescription) Ioctl(ctx context.Context, io usermem.IO, args arch.SyscallArguments) (uintptr, error) { - t := kernel.TaskFromContext(ctx) - if t == nil { - // ioctl(2) may only be called from a task goroutine. - return 0, syserror.ENOTTY - } - - switch cmd := args[1].Uint(); cmd { - case linux.FIONREAD: // linux.FIONREAD == linux.TIOCINQ - // Get the number of bytes in the input queue read buffer. - return 0, sfd.inode.t.ld.inputQueueReadSize(t, io, args) - case linux.TCGETS: - return sfd.inode.t.ld.getTermios(t, args) - case linux.TCSETS: - return sfd.inode.t.ld.setTermios(t, args) - case linux.TCSETSW: - // TODO(b/29356795): This should drain the output queue first. - return sfd.inode.t.ld.setTermios(t, args) - case linux.TIOCGPTN: - nP := primitive.Uint32(sfd.inode.t.n) - _, err := nP.CopyOut(t, args[2].Pointer()) - return 0, err - case linux.TIOCGWINSZ: - return 0, sfd.inode.t.ld.windowSize(t, args) - case linux.TIOCSWINSZ: - return 0, sfd.inode.t.ld.setWindowSize(t, args) - case linux.TIOCSCTTY: - // Make the given terminal the controlling terminal of the - // calling process. - return 0, sfd.inode.t.setControllingTTY(ctx, args, false /* isMaster */) - case linux.TIOCNOTTY: - // Release this process's controlling terminal. - return 0, sfd.inode.t.releaseControllingTTY(ctx, args, false /* isMaster */) - case linux.TIOCGPGRP: - // Get the foreground process group. - return sfd.inode.t.foregroundProcessGroup(ctx, args, false /* isMaster */) - case linux.TIOCSPGRP: - // Set the foreground process group. - return sfd.inode.t.setForegroundProcessGroup(ctx, args, false /* isMaster */) - default: - maybeEmitUnimplementedEvent(ctx, cmd) - return 0, syserror.ENOTTY - } -} - -// SetStat implements vfs.FileDescriptionImpl.SetStat. -func (sfd *slaveFileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { - creds := auth.CredentialsFromContext(ctx) - fs := sfd.vfsfd.VirtualDentry().Mount().Filesystem() - return sfd.inode.SetStat(ctx, fs, creds, opts) -} - -// Stat implements vfs.FileDescriptionImpl.Stat. -func (sfd *slaveFileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linux.Statx, error) { - fs := sfd.vfsfd.VirtualDentry().Mount().Filesystem() - return sfd.inode.Stat(ctx, fs, opts) -} - -// LockPOSIX implements vfs.FileDescriptionImpl.LockPOSIX. -func (sfd *slaveFileDescription) LockPOSIX(ctx context.Context, uid fslock.UniqueID, t fslock.LockType, start, length uint64, whence int16, block fslock.Blocker) error { - return sfd.Locks().LockPOSIX(ctx, &sfd.vfsfd, uid, t, start, length, whence, block) -} - -// UnlockPOSIX implements vfs.FileDescriptionImpl.UnlockPOSIX. -func (sfd *slaveFileDescription) UnlockPOSIX(ctx context.Context, uid fslock.UniqueID, start, length uint64, whence int16) error { - return sfd.Locks().UnlockPOSIX(ctx, &sfd.vfsfd, uid, start, length, whence) -} diff --git a/pkg/sentry/fsimpl/devpts/terminal.go b/pkg/sentry/fsimpl/devpts/terminal.go index e88eb6360..731955d62 100644 --- a/pkg/sentry/fsimpl/devpts/terminal.go +++ b/pkg/sentry/fsimpl/devpts/terminal.go @@ -36,18 +36,18 @@ type Terminal struct { // this terminal. This field is immutable. masterKTTY *kernel.TTY - // slaveKTTY contains the controlling process of the slave end of this + // replicaKTTY contains the controlling process of the replica end of this // terminal. This field is immutable. - slaveKTTY *kernel.TTY + replicaKTTY *kernel.TTY } func newTerminal(n uint32) *Terminal { - termios := linux.DefaultSlaveTermios + termios := linux.DefaultReplicaTermios t := Terminal{ - n: n, - ld: newLineDiscipline(termios), - masterKTTY: &kernel.TTY{Index: n}, - slaveKTTY: &kernel.TTY{Index: n}, + n: n, + ld: newLineDiscipline(termios), + masterKTTY: &kernel.TTY{Index: n}, + replicaKTTY: &kernel.TTY{Index: n}, } return &t } @@ -113,5 +113,5 @@ func (tm *Terminal) tty(isMaster bool) *kernel.TTY { if isMaster { return tm.masterKTTY } - return tm.slaveKTTY + return tm.replicaKTTY } diff --git a/pkg/sentry/fsimpl/host/host.go b/pkg/sentry/fsimpl/host/host.go index 7561f821c..1bd0e4ee8 100644 --- a/pkg/sentry/fsimpl/host/host.go +++ b/pkg/sentry/fsimpl/host/host.go @@ -496,7 +496,7 @@ func (i *inode) open(ctx context.Context, d *vfs.Dentry, mnt *vfs.Mount, flags u if i.isTTY { fd := &TTYFileDescription{ fileDescription: fileDescription{inode: i}, - termios: linux.DefaultSlaveTermios, + termios: linux.DefaultReplicaTermios, } fd.LockFD.Init(&i.locks) vfsfd := &fd.vfsfd -- cgit v1.2.3