diff options
| -rw-r--r-- | pkg/sentry/devices/ttydev/BUILD | 16 | ||||
| -rw-r--r-- | pkg/sentry/devices/ttydev/ttydev.go | 91 | ||||
| -rw-r--r-- | runsc/boot/BUILD | 1 | ||||
| -rw-r--r-- | runsc/boot/vfs.go | 7 | ||||
| -rw-r--r-- | test/syscalls/BUILD | 1 |
5 files changed, 116 insertions, 0 deletions
diff --git a/pkg/sentry/devices/ttydev/BUILD b/pkg/sentry/devices/ttydev/BUILD new file mode 100644 index 000000000..12e49b58a --- /dev/null +++ b/pkg/sentry/devices/ttydev/BUILD @@ -0,0 +1,16 @@ +load("//tools:defs.bzl", "go_library") + +licenses(["notice"]) + +go_library( + name = "ttydev", + srcs = ["ttydev.go"], + visibility = ["//pkg/sentry:internal"], + deps = [ + "//pkg/abi/linux", + "//pkg/context", + "//pkg/sentry/fsimpl/devtmpfs", + "//pkg/sentry/vfs", + "//pkg/usermem", + ], +) diff --git a/pkg/sentry/devices/ttydev/ttydev.go b/pkg/sentry/devices/ttydev/ttydev.go new file mode 100644 index 000000000..fbb7fd92c --- /dev/null +++ b/pkg/sentry/devices/ttydev/ttydev.go @@ -0,0 +1,91 @@ +// 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 ttydev implements devices for /dev/tty and (eventually) +// /dev/console. +// +// TODO(b/159623826): Support /dev/console. +package ttydev + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/devtmpfs" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/usermem" +) + +const ( + // See drivers/tty/tty_io.c:tty_init(). + ttyDevMinor = 0 + consoleDevMinor = 1 +) + +// ttyDevice implements vfs.Device for /dev/tty. +type ttyDevice struct{} + +// Open implements vfs.Device.Open. +func (ttyDevice) Open(ctx context.Context, mnt *vfs.Mount, vfsd *vfs.Dentry, opts vfs.OpenOptions) (*vfs.FileDescription, error) { + fd := &ttyFD{} + if err := fd.vfsfd.Init(fd, opts.Flags, mnt, vfsd, &vfs.FileDescriptionOptions{ + UseDentryMetadata: true, + }); err != nil { + return nil, err + } + return &fd.vfsfd, nil +} + +// ttyFD implements vfs.FileDescriptionImpl for /dev/tty. +type ttyFD struct { + vfsfd vfs.FileDescription + vfs.FileDescriptionDefaultImpl + vfs.DentryMetadataFileDescriptionImpl + vfs.NoLockFD +} + +// Release implements vfs.FileDescriptionImpl.Release. +func (fd *ttyFD) Release() {} + +// PRead implements vfs.FileDescriptionImpl.PRead. +func (fd *ttyFD) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { + return 0, nil +} + +// Read implements vfs.FileDescriptionImpl.Read. +func (fd *ttyFD) Read(ctx context.Context, dst usermem.IOSequence, opts vfs.ReadOptions) (int64, error) { + return 0, nil +} + +// PWrite implements vfs.FileDescriptionImpl.PWrite. +func (fd *ttyFD) PWrite(ctx context.Context, src usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) { + return src.NumBytes(), nil +} + +// Write implements vfs.FileDescriptionImpl.Write. +func (fd *ttyFD) Write(ctx context.Context, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) { + return src.NumBytes(), nil +} + +// Register registers all devices implemented by this package in vfsObj. +func Register(vfsObj *vfs.VirtualFilesystem) error { + return vfsObj.RegisterDevice(vfs.CharDevice, linux.TTYAUX_MAJOR, ttyDevMinor, ttyDevice{}, &vfs.RegisterDeviceOptions{ + GroupName: "tty", + }) +} + +// CreateDevtmpfsFiles creates device special files in dev representing all +// devices implemented by this package. +func CreateDevtmpfsFiles(ctx context.Context, dev *devtmpfs.Accessor) error { + return dev.CreateDeviceFile(ctx, "tty", vfs.CharDevice, linux.TTYAUX_MAJOR, ttyDevMinor, 0666 /* mode */) +} diff --git a/runsc/boot/BUILD b/runsc/boot/BUILD index 2b1e6b13e..b701c65d2 100644 --- a/runsc/boot/BUILD +++ b/runsc/boot/BUILD @@ -40,6 +40,7 @@ go_library( "//pkg/sentry/arch:registers_go_proto", "//pkg/sentry/control", "//pkg/sentry/devices/memdev", + "//pkg/sentry/devices/ttydev", "//pkg/sentry/fdimport", "//pkg/sentry/fs", "//pkg/sentry/fs/dev", diff --git a/runsc/boot/vfs.go b/runsc/boot/vfs.go index d1653b279..2fdddc719 100644 --- a/runsc/boot/vfs.go +++ b/runsc/boot/vfs.go @@ -26,6 +26,7 @@ import ( "gvisor.dev/gvisor/pkg/fspath" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/sentry/devices/memdev" + "gvisor.dev/gvisor/pkg/sentry/devices/ttydev" "gvisor.dev/gvisor/pkg/sentry/fs/user" "gvisor.dev/gvisor/pkg/sentry/fsimpl/devpts" "gvisor.dev/gvisor/pkg/sentry/fsimpl/devtmpfs" @@ -75,6 +76,9 @@ func registerFilesystems(ctx context.Context, vfsObj *vfs.VirtualFilesystem, cre if err := memdev.Register(vfsObj); err != nil { return fmt.Errorf("registering memdev: %w", err) } + if err := ttydev.Register(vfsObj); err != nil { + return fmt.Errorf("registering ttydev: %w", err) + } a, err := devtmpfs.NewAccessor(ctx, vfsObj, creds, devtmpfs.Name) if err != nil { return fmt.Errorf("creating devtmpfs accessor: %w", err) @@ -87,6 +91,9 @@ func registerFilesystems(ctx context.Context, vfsObj *vfs.VirtualFilesystem, cre if err := memdev.CreateDevtmpfsFiles(ctx, a); err != nil { return fmt.Errorf("creating devtmpfs files: %w", err) } + if err := ttydev.CreateDevtmpfsFiles(ctx, a); err != nil { + return fmt.Errorf("creating devtmpfs files: %w", err) + } return nil } diff --git a/test/syscalls/BUILD b/test/syscalls/BUILD index 8ce5d24f4..315af9efe 100644 --- a/test/syscalls/BUILD +++ b/test/syscalls/BUILD @@ -147,6 +147,7 @@ syscall_test( syscall_test( test = "//test/syscalls/linux:dev_test", + vfs2 = "True", ) syscall_test( |