Add itimer types to linux package, strace

PiperOrigin-RevId: 215278262
Change-Id: Icd10384c99802be6097be938196044386441e282

pkg/abi/linux/BUILD

@@ -44,6 +44,7 @@ go_library(
         "signal.go",
         "socket.go",
         "time.go",
+        "timer.go",
         "tty.go",
         "uio.go",
         "utsname.go",

pkg/abi/linux/timer.go

@@ -0,0 +1,23 @@
+// 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 linux
+
+// itimer types for getitimer(2) and setitimer(2), from
+// include/uapi/linux/time.h.
+const (
+	ITIMER_REAL    = 0
+	ITIMER_VIRTUAL = 1
+	ITIMER_PROF    = 2
+)

pkg/sentry/strace/linux64.go

@@ -53,9 +53,9 @@ var linuxAMD64 = SyscallMap{
 	33:  makeSyscallInfo("dup2", Hex, Hex),
 	34:  makeSyscallInfo("pause"),
 	35:  makeSyscallInfo("nanosleep", Timespec, PostTimespec),
-	36:  makeSyscallInfo("getitimer", Hex, PostItimerVal),
+	36:  makeSyscallInfo("getitimer", ItimerType, PostItimerVal),
 	37:  makeSyscallInfo("alarm", Hex),
-	38:  makeSyscallInfo("setitimer", Hex, ItimerVal, PostItimerVal),
+	38:  makeSyscallInfo("setitimer", ItimerType, ItimerVal, PostItimerVal),
 	39:  makeSyscallInfo("getpid"),
 	40:  makeSyscallInfo("sendfile", Hex, Hex, Hex, Hex),
 	41:  makeSyscallInfo("socket", SockFamily, SockType, SockProtocol),

pkg/sentry/strace/strace.go

@@ -24,6 +24,7 @@ import (
 	"syscall"
 	"time"
 
+	"gvisor.googlesource.com/gvisor/pkg/abi"
 	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
 	"gvisor.googlesource.com/gvisor/pkg/bits"
 	"gvisor.googlesource.com/gvisor/pkg/eventchannel"
@@ -46,6 +47,22 @@ var LogMaximumSize uint = DefaultLogMaximumSize
 // do anything useful with binary text dump of byte array arguments.
 var EventMaximumSize uint
 
+// ItimerTypes are the possible itimer types.
+var ItimerTypes = abi.ValueSet{
+	{
+		Value: linux.ITIMER_REAL,
+		Name:  "ITIMER_REAL",
+	},
+	{
+		Value: linux.ITIMER_VIRTUAL,
+		Name:  "ITIMER_VIRTUAL",
+	},
+	{
+		Value: linux.ITIMER_PROF,
+		Name:  "ITIMER_PROF",
+	},
+}
+
 func iovecs(t *kernel.Task, addr usermem.Addr, iovcnt int, printContent bool, maxBytes uint64) string {
 	if iovcnt < 0 || iovcnt > linux.UIO_MAXIOV {
 		return fmt.Sprintf("%#x (error decoding iovecs: invalid iovcnt)", addr)
@@ -322,6 +339,8 @@ func (i *SyscallInfo) pre(t *kernel.Task, args arch.SyscallArguments, maximumBlo
 			output = append(output, futex(uint64(args[arg].Uint())))
 		case PtraceRequest:
 			output = append(output, PtraceRequestSet.Parse(args[arg].Uint64()))
+		case ItimerType:
+			output = append(output, ItimerTypes.Parse(uint64(args[arg].Int())))
 		case Oct:
 			output = append(output, "0o"+strconv.FormatUint(args[arg].Uint64(), 8))
 		case Hex:

pkg/sentry/strace/syscalls.go

@@ -150,6 +150,9 @@ const (
 	// Utimbuf is a pointer to a struct utimbuf.
 	Utimbuf
 
+	// Rusage is a struct rusage, formatted after syscall execution.
+	Rusage
+
 	// CloneFlags are clone(2) flags.
 	CloneFlags
 
@@ -165,8 +168,8 @@ const (
 	// PtraceRequest is the ptrace(2) request.
 	PtraceRequest
 
-	// Rusage is a struct rusage, formatted after syscall execution.
-	Rusage
+	// ItimerType is an itimer type (ITIMER_REAL, etc).
+	ItimerType
 )
 
 // defaultFormat is the syscall argument format to use if the actual format is

pkg/sentry/syscalls/linux/sys_timer.go

@@ -25,19 +25,6 @@ import (
 	"gvisor.googlesource.com/gvisor/pkg/sentry/usermem"
 )
 
-// ItimerType denotes the type of interval timer.
-type ItimerType int
-
-// Interval timer types from <sys/time.h>.
-const (
-	// ItimerReal equals to ITIMER_REAL.
-	ItimerReal ItimerType = iota
-	// ItimerVirtual equals to ITIMER_VIRTUAL.
-	ItimerVirtual
-	// ItimerProf equals to ITIMER_PROF.
-	ItimerProf
-)
-
 const nsecPerSec = int64(time.Second)
 
 // copyItimerValIn copies an ItimerVal from the untrusted app range to the
@@ -83,13 +70,13 @@ func copyItimerValOut(t *kernel.Task, addr usermem.Addr, itv *linux.ItimerVal) e
 	}
 }
 
-func findTimer(t *kernel.Task, w ItimerType) (*ktime.Timer, error) {
-	switch w {
-	case ItimerReal:
+func findTimer(t *kernel.Task, which int32) (*ktime.Timer, error) {
+	switch which {
+	case linux.ITIMER_REAL:
 		return t.ThreadGroup().Timer().RealTimer, nil
-	case ItimerVirtual:
+	case linux.ITIMER_VIRTUAL:
 		return t.ThreadGroup().Timer().VirtualTimer, nil
-	case ItimerProf:
+	case linux.ITIMER_PROF:
 		return t.ThreadGroup().Timer().ProfTimer, nil
 	default:
 		return nil, syscall.EINVAL
@@ -98,7 +85,7 @@ func findTimer(t *kernel.Task, w ItimerType) (*ktime.Timer, error) {
 
 // Getitimer implements linux syscall getitimer(2).
 func Getitimer(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
-	timerID := ItimerType(args[0].Int())
+	timerID := args[0].Int()
 	val := args[1].Pointer()
 
 	timer, err := findTimer(t, timerID)
@@ -116,7 +103,7 @@ func Getitimer(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys
 
 // Setitimer implements linux syscall setitimer(2).
 func Setitimer(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
-	timerID := ItimerType(args[0].Int())
+	timerID := args[0].Int()
 	newVal := args[1].Pointer()
 	oldVal := args[2].Pointer()