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-rw-r--r--pkg/sentry/control/BUILD39
-rw-r--r--pkg/sentry/control/control.go17
-rw-r--r--pkg/sentry/control/proc.go293
-rw-r--r--pkg/sentry/control/proc_test.go164
4 files changed, 513 insertions, 0 deletions
diff --git a/pkg/sentry/control/BUILD b/pkg/sentry/control/BUILD
new file mode 100644
index 000000000..4d1d0d019
--- /dev/null
+++ b/pkg/sentry/control/BUILD
@@ -0,0 +1,39 @@
+package(licenses = ["notice"]) # Apache 2.0
+
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
+
+go_library(
+ name = "control",
+ srcs = [
+ "control.go",
+ "proc.go",
+ ],
+ importpath = "gvisor.googlesource.com/gvisor/pkg/sentry/control",
+ visibility = [
+ "//pkg/sentry:internal",
+ ],
+ deps = [
+ "//pkg/abi/linux",
+ "//pkg/sentry/fs",
+ "//pkg/sentry/fs/host",
+ "//pkg/sentry/kernel",
+ "//pkg/sentry/kernel/auth",
+ "//pkg/sentry/kernel/kdefs",
+ "//pkg/sentry/kernel/time",
+ "//pkg/sentry/limits",
+ "//pkg/sentry/usage",
+ "//pkg/urpc",
+ ],
+)
+
+go_test(
+ name = "control_test",
+ size = "small",
+ srcs = ["proc_test.go"],
+ embed = [":control"],
+ deps = [
+ "//pkg/log",
+ "//pkg/sentry/kernel/time",
+ "//pkg/sentry/usage",
+ ],
+)
diff --git a/pkg/sentry/control/control.go b/pkg/sentry/control/control.go
new file mode 100644
index 000000000..a6ee6e649
--- /dev/null
+++ b/pkg/sentry/control/control.go
@@ -0,0 +1,17 @@
+// Copyright 2018 Google Inc.
+//
+// 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 control contains types that expose control server methods, and can
+// be used to configure and interact with a running sandbox process.
+package control
diff --git a/pkg/sentry/control/proc.go b/pkg/sentry/control/proc.go
new file mode 100644
index 000000000..7d06a1d04
--- /dev/null
+++ b/pkg/sentry/control/proc.go
@@ -0,0 +1,293 @@
+// Copyright 2018 Google Inc.
+//
+// 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 control
+
+import (
+ "bytes"
+ "encoding/json"
+ "fmt"
+ "syscall"
+ "text/tabwriter"
+ "time"
+
+ "gvisor.googlesource.com/gvisor/pkg/abi/linux"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/fs"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/fs/host"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/kernel"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/auth"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/kdefs"
+ ktime "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/limits"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/usage"
+ "gvisor.googlesource.com/gvisor/pkg/urpc"
+)
+
+// Proc includes task-related functions.
+//
+// At the moment, this is limited to exec support.
+type Proc struct {
+ Kernel *kernel.Kernel
+}
+
+// ExecArgs is the set of arguments to exec.
+type ExecArgs struct {
+ // Filename is the filename to load.
+ //
+ // If this is provided as "", then the file will be guessed via Argv[0].
+ Filename string `json:"filename"`
+
+ // Argv is a list of arguments.
+ Argv []string `json:"argv"`
+
+ // Envv is a list of environment variables.
+ Envv []string `json:"envv"`
+
+ // WorkingDirectory defines the working directory for the new process.
+ WorkingDirectory string `json:"wd"`
+
+ // KUID is the UID to run with in the root user namespace. Defaults to
+ // root if not set explicitly.
+ KUID auth.KUID
+
+ // KGID is the GID to run with in the root user namespace. Defaults to
+ // the root group if not set explicitly.
+ KGID auth.KGID
+
+ // ExtraKGIDs is the list of additional groups to which the user
+ // belongs.
+ ExtraKGIDs []auth.KGID
+
+ // Capabilities is the list of capabilities to give to the process.
+ Capabilities *auth.TaskCapabilities
+
+ // Detach indicates whether Exec should detach once the process starts.
+ Detach bool
+
+ // FilePayload determines the files to give to the new process.
+ urpc.FilePayload
+}
+
+// Exec runs a new task.
+func (proc *Proc) Exec(args *ExecArgs, waitStatus *uint32) error {
+ // Import file descriptors.
+ l := limits.NewLimitSet()
+ fdm := proc.Kernel.NewFDMap()
+ defer fdm.DecRef()
+
+ creds := auth.NewUserCredentials(
+ args.KUID,
+ args.KGID,
+ args.ExtraKGIDs,
+ args.Capabilities,
+ proc.Kernel.RootUserNamespace())
+
+ initArgs := kernel.CreateProcessArgs{
+ Filename: args.Filename,
+ Argv: args.Argv,
+ Envv: args.Envv,
+ WorkingDirectory: args.WorkingDirectory,
+ Credentials: creds,
+ FDMap: fdm,
+ Umask: 0022,
+ Limits: l,
+ MaxSymlinkTraversals: linux.MaxSymlinkTraversals,
+ UTSNamespace: proc.Kernel.RootUTSNamespace(),
+ IPCNamespace: proc.Kernel.RootIPCNamespace(),
+ }
+ ctx := initArgs.NewContext(proc.Kernel)
+ mounter := fs.FileOwnerFromContext(ctx)
+
+ for appFD, f := range args.FilePayload.Files {
+ // Copy the underlying FD.
+ newFD, err := syscall.Dup(int(f.Fd()))
+ if err != nil {
+ return err
+ }
+ f.Close()
+
+ // Install the given file as an FD.
+ file, err := host.NewFile(ctx, newFD, mounter)
+ if err != nil {
+ syscall.Close(newFD)
+ return err
+ }
+ defer file.DecRef()
+ if err := fdm.NewFDAt(kdefs.FD(appFD), file, kernel.FDFlags{}, l); err != nil {
+ return err
+ }
+ }
+
+ // Start the new task.
+ newTG, err := proc.Kernel.CreateProcess(initArgs)
+ if err != nil {
+ return err
+ }
+
+ // If we're supposed to detach, don't wait for the process to exit.
+ if args.Detach {
+ *waitStatus = 0
+ return nil
+ }
+
+ // Wait for completion.
+ newTG.WaitExited()
+ *waitStatus = newTG.ExitStatus().Status()
+ return nil
+}
+
+// PsArgs is the set of arguments to ps.
+type PsArgs struct {
+ // JSON will force calls to Ps to return the result as a JSON payload.
+ JSON bool
+}
+
+// Ps provides a process listing for the running kernel.
+func (proc *Proc) Ps(args *PsArgs, out *string) error {
+ var p []*Process
+ if e := Processes(proc.Kernel, &p); e != nil {
+ return e
+ }
+ if !args.JSON {
+ *out = ProcessListToTable(p)
+ } else {
+ s, e := ProcessListToJSON(p)
+ if e != nil {
+ return e
+ }
+ *out = s
+ }
+ return nil
+}
+
+// Process contains information about a single process in a Sandbox.
+// TODO: Implement TTY field.
+type Process struct {
+ UID auth.KUID `json:"uid"`
+ PID kernel.ThreadID `json:"pid"`
+ // Parent PID
+ PPID kernel.ThreadID `json:"ppid"`
+ // Processor utilization
+ C int32 `json:"c"`
+ // Start time
+ STime string `json:"stime"`
+ // CPU time
+ Time string `json:"time"`
+ // Executable shortname (e.g. "sh" for /bin/sh)
+ Cmd string `json:"cmd"`
+}
+
+// ProcessListToTable prints a table with the following format:
+// UID PID PPID C STIME TIME CMD
+// 0 1 0 0 14:04 505262ns tail
+func ProcessListToTable(pl []*Process) string {
+ var buf bytes.Buffer
+ tw := tabwriter.NewWriter(&buf, 10, 1, 3, ' ', 0)
+ fmt.Fprint(tw, "UID\tPID\tPPID\tC\tSTIME\tTIME\tCMD")
+ for _, d := range pl {
+ fmt.Fprintf(tw, "\n%d\t%d\t%d\t%d\t%s\t%s\t%s",
+ d.UID,
+ d.PID,
+ d.PPID,
+ d.C,
+ d.STime,
+ d.Time,
+ d.Cmd)
+ }
+ tw.Flush()
+ return buf.String()
+}
+
+// ProcessListToJSON will return the JSON representation of ps.
+func ProcessListToJSON(pl []*Process) (string, error) {
+ b, err := json.Marshal(pl)
+ if err != nil {
+ return "", fmt.Errorf("couldn't marshal process list %v: %v", pl, err)
+ }
+ return string(b), nil
+}
+
+// PrintPIDsJSON prints a JSON object containing only the PIDs in pl. This
+// behavior is the same as runc's.
+func PrintPIDsJSON(pl []*Process) (string, error) {
+ pids := make([]kernel.ThreadID, 0, len(pl))
+ for _, d := range pl {
+ pids = append(pids, d.PID)
+ }
+ b, err := json.Marshal(pids)
+ if err != nil {
+ return "", fmt.Errorf("couldn't marshal PIDs %v: %v", pids, err)
+ }
+ return string(b), nil
+}
+
+// Processes retrieves information about processes running in the sandbox.
+func Processes(k *kernel.Kernel, out *[]*Process) error {
+ ts := k.TaskSet()
+ now := k.RealtimeClock().Now()
+ for _, tg := range ts.Root.ThreadGroups() {
+ pid := ts.Root.IDOfThreadGroup(tg)
+ // If tg has already been reaped ignore it.
+ if pid == 0 {
+ continue
+ }
+
+ *out = append(*out, &Process{
+ UID: tg.Leader().Credentials().EffectiveKUID,
+ PID: pid,
+ // If Parent is null (i.e. tg is the init process), PPID will be 0.
+ PPID: ts.Root.IDOfTask(tg.Leader().Parent()),
+ STime: formatStartTime(now, tg.Leader().StartTime()),
+ C: percentCPU(tg.CPUStats(), tg.Leader().StartTime(), now),
+ Time: tg.CPUStats().SysTime.String(),
+ Cmd: tg.Leader().Name(),
+ })
+ }
+ return nil
+}
+
+// formatStartTime formats startTime depending on the current time:
+// - If startTime was today, HH:MM is used.
+// - If startTime was not today but was this year, MonDD is used (e.g. Jan02)
+// - If startTime was not this year, the year is used.
+func formatStartTime(now, startTime ktime.Time) string {
+ nowS, nowNs := now.Unix()
+ n := time.Unix(nowS, nowNs)
+ startTimeS, startTimeNs := startTime.Unix()
+ st := time.Unix(startTimeS, startTimeNs)
+ format := "15:04"
+ if st.YearDay() != n.YearDay() {
+ format = "Jan02"
+ }
+ if st.Year() != n.Year() {
+ format = "2006"
+ }
+ return st.Format(format)
+}
+
+func percentCPU(stats usage.CPUStats, startTime, now ktime.Time) int32 {
+ // Note: In procps, there is an option to include child CPU stats. As
+ // it is disabled by default, we do not include them.
+ total := stats.UserTime + stats.SysTime
+ lifetime := now.Sub(startTime)
+ if lifetime <= 0 {
+ return 0
+ }
+ percentCPU := total * 100 / lifetime
+ // Cap at 99% since procps does the same.
+ if percentCPU > 99 {
+ percentCPU = 99
+ }
+ return int32(percentCPU)
+}
diff --git a/pkg/sentry/control/proc_test.go b/pkg/sentry/control/proc_test.go
new file mode 100644
index 000000000..18286496f
--- /dev/null
+++ b/pkg/sentry/control/proc_test.go
@@ -0,0 +1,164 @@
+// Copyright 2018 Google Inc.
+//
+// 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 control
+
+import (
+ "testing"
+
+ "gvisor.googlesource.com/gvisor/pkg/log"
+ ktime "gvisor.googlesource.com/gvisor/pkg/sentry/kernel/time"
+ "gvisor.googlesource.com/gvisor/pkg/sentry/usage"
+)
+
+func init() {
+ log.SetLevel(log.Debug)
+}
+
+// Tests that ProcessData.Table() prints with the correct format.
+func TestProcessListTable(t *testing.T) {
+ testCases := []struct {
+ pl []*Process
+ expected string
+ }{
+ {
+ pl: []*Process{},
+ expected: "UID PID PPID C STIME TIME CMD",
+ },
+ {
+ pl: []*Process{
+ &Process{
+ UID: 0,
+ PID: 0,
+ PPID: 0,
+ C: 0,
+ STime: "0",
+ Time: "0",
+ Cmd: "zero",
+ },
+ &Process{
+ UID: 1,
+ PID: 1,
+ PPID: 1,
+ C: 1,
+ STime: "1",
+ Time: "1",
+ Cmd: "one",
+ },
+ },
+ expected: `UID PID PPID C STIME TIME CMD
+0 0 0 0 0 0 zero
+1 1 1 1 1 1 one`,
+ },
+ }
+
+ for _, tc := range testCases {
+ output := ProcessListToTable(tc.pl)
+
+ if tc.expected != output {
+ t.Errorf("PrintTable(%v): got:\n%s\nwant:\n%s", tc.pl, output, tc.expected)
+ }
+ }
+}
+
+func TestProcessListJSON(t *testing.T) {
+ testCases := []struct {
+ pl []*Process
+ expected string
+ }{
+ {
+ pl: []*Process{},
+ expected: "[]",
+ },
+ {
+ pl: []*Process{
+ &Process{
+ UID: 0,
+ PID: 0,
+ PPID: 0,
+ C: 0,
+ STime: "0",
+ Time: "0",
+ Cmd: "zero",
+ },
+ &Process{
+ UID: 1,
+ PID: 1,
+ PPID: 1,
+ C: 1,
+ STime: "1",
+ Time: "1",
+ Cmd: "one",
+ },
+ },
+ expected: "[0,1]",
+ },
+ }
+
+ for _, tc := range testCases {
+ output, err := PrintPIDsJSON(tc.pl)
+ if err != nil {
+ t.Errorf("failed to generate JSON: %v", err)
+ }
+
+ if tc.expected != output {
+ t.Errorf("PrintJSON(%v): got:\n%s\nwant:\n%s", tc.pl, output, tc.expected)
+ }
+ }
+}
+
+func TestPercentCPU(t *testing.T) {
+ testCases := []struct {
+ stats usage.CPUStats
+ startTime ktime.Time
+ now ktime.Time
+ expected int32
+ }{
+ {
+ // Verify that 100% use is capped at 99.
+ stats: usage.CPUStats{UserTime: 1e9, SysTime: 1e9},
+ startTime: ktime.FromNanoseconds(7e9),
+ now: ktime.FromNanoseconds(9e9),
+ expected: 99,
+ },
+ {
+ // Verify that if usage > lifetime, we get at most 99%
+ // usage.
+ stats: usage.CPUStats{UserTime: 2e9, SysTime: 2e9},
+ startTime: ktime.FromNanoseconds(7e9),
+ now: ktime.FromNanoseconds(9e9),
+ expected: 99,
+ },
+ {
+ // Verify that 50% usage is reported correctly.
+ stats: usage.CPUStats{UserTime: 1e9, SysTime: 1e9},
+ startTime: ktime.FromNanoseconds(12e9),
+ now: ktime.FromNanoseconds(16e9),
+ expected: 50,
+ },
+ {
+ // Verify that 0% usage is reported correctly.
+ stats: usage.CPUStats{UserTime: 0, SysTime: 0},
+ startTime: ktime.FromNanoseconds(12e9),
+ now: ktime.FromNanoseconds(14e9),
+ expected: 0,
+ },
+ }
+
+ for _, tc := range testCases {
+ if pcpu := percentCPU(tc.stats, tc.startTime, tc.now); pcpu != tc.expected {
+ t.Errorf("percentCPU(%v, %v, %v): got %d, want %d", tc.stats, tc.startTime, tc.now, pcpu, tc.expected)
+ }
+ }
+}