[op] Replace syscall package usage with golang.org/x/sys/unix in pkg/.

The syscall package has been deprecated in favor of golang.org/x/sys.

Note that syscall is still used in the following places:
- pkg/sentry/socket/hostinet/stack.go: some netlink related functionalities
  are not yet available in golang.org/x/sys.
- syscall.Stat_t is still used in some places because os.FileInfo.Sys() still
  returns it and not unix.Stat_t.

Updates #214

PiperOrigin-RevId: 360701387

2 files changed, 14 insertions, 16 deletions

diff --git a/pkg/sentry/socket/netstack/netstack.go b/pkg/sentry/socket/netstack/netstack.go
index f77a867f1..f2dc7c90b 100644
--- a/pkg/sentry/socket/netstack/netstack.go
+++ b/pkg/sentry/socket/netstack/netstack.go
@@ -31,7 +31,6 @@ import (
 	"io/ioutil"
 	"math"
 	"reflect"
-	"syscall"
 	"time"
 
 	"golang.org/x/sys/unix"
@@ -835,7 +834,7 @@ func getSockOptSocket(t *kernel.Task, s socket.SocketOps, ep commonEndpoint, fam
 		return &optP, nil
 
 	case linux.SO_PEERCRED:
-		if family != linux.AF_UNIX || outLen < syscall.SizeofUcred {
+		if family != linux.AF_UNIX || outLen < unix.SizeofUcred {
 			return nil, syserr.ErrInvalidArgument
 		}
 
@@ -3199,15 +3198,15 @@ func nicStateFlagsToLinux(f stack.NICStateFlags) uint32 {
 }
 
 func isTCPSocket(skType linux.SockType, skProto int) bool {
-	return skType == linux.SOCK_STREAM && (skProto == 0 || skProto == syscall.IPPROTO_TCP)
+	return skType == linux.SOCK_STREAM && (skProto == 0 || skProto == unix.IPPROTO_TCP)
 }
 
 func isUDPSocket(skType linux.SockType, skProto int) bool {
-	return skType == linux.SOCK_DGRAM && (skProto == 0 || skProto == syscall.IPPROTO_UDP)
+	return skType == linux.SOCK_DGRAM && (skProto == 0 || skProto == unix.IPPROTO_UDP)
 }
 
 func isICMPSocket(skType linux.SockType, skProto int) bool {
-	return skType == linux.SOCK_DGRAM && (skProto == syscall.IPPROTO_ICMP || skProto == syscall.IPPROTO_ICMPV6)
+	return skType == linux.SOCK_DGRAM && (skProto == unix.IPPROTO_ICMP || skProto == unix.IPPROTO_ICMPV6)
 }
 
 // State implements socket.Socket.State. State translates the internal state
diff --git a/pkg/sentry/socket/netstack/provider.go b/pkg/sentry/socket/netstack/provider.go
index 2515dda80..8605ad507 100644
--- a/pkg/sentry/socket/netstack/provider.go
+++ b/pkg/sentry/socket/netstack/provider.go
@@ -15,8 +15,7 @@
 package netstack
 
 import (
-	"syscall"
-
+	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/abi/linux"
 	"gvisor.dev/gvisor/pkg/context"
 	"gvisor.dev/gvisor/pkg/sentry/fs"
@@ -48,18 +47,18 @@ type provider struct {
 func getTransportProtocol(ctx context.Context, stype linux.SockType, protocol int) (tcpip.TransportProtocolNumber, bool, *syserr.Error) {
 	switch stype {
 	case linux.SOCK_STREAM:
-		if protocol != 0 && protocol != syscall.IPPROTO_TCP {
+		if protocol != 0 && protocol != unix.IPPROTO_TCP {
 			return 0, true, syserr.ErrInvalidArgument
 		}
 		return tcp.ProtocolNumber, true, nil
 
 	case linux.SOCK_DGRAM:
 		switch protocol {
-		case 0, syscall.IPPROTO_UDP:
+		case 0, unix.IPPROTO_UDP:
 			return udp.ProtocolNumber, true, nil
-		case syscall.IPPROTO_ICMP:
+		case unix.IPPROTO_ICMP:
 			return header.ICMPv4ProtocolNumber, true, nil
-		case syscall.IPPROTO_ICMPV6:
+		case unix.IPPROTO_ICMPV6:
 			return header.ICMPv6ProtocolNumber, true, nil
 		}
 
@@ -71,18 +70,18 @@ func getTransportProtocol(ctx context.Context, stype linux.SockType, protocol in
 		}
 
 		switch protocol {
-		case syscall.IPPROTO_ICMP:
+		case unix.IPPROTO_ICMP:
 			return header.ICMPv4ProtocolNumber, true, nil
-		case syscall.IPPROTO_ICMPV6:
+		case unix.IPPROTO_ICMPV6:
 			return header.ICMPv6ProtocolNumber, true, nil
-		case syscall.IPPROTO_UDP:
+		case unix.IPPROTO_UDP:
 			return header.UDPProtocolNumber, true, nil
-		case syscall.IPPROTO_TCP:
+		case unix.IPPROTO_TCP:
 			return header.TCPProtocolNumber, true, nil
 		// IPPROTO_RAW signifies that the raw socket isn't assigned to
 		// a transport protocol. Users will be able to write packets'
 		// IP headers and won't receive anything.
-		case syscall.IPPROTO_RAW:
+		case unix.IPPROTO_RAW:
 			return tcpip.TransportProtocolNumber(0), false, nil
 		}
 	}