Merge branch 'master' into ip-forwarding

- Merges aleksej-paschenko's with HEAD
- Adds vfs2 support for ip_forward

1 files changed, 73 insertions, 26 deletions

diff --git a/pkg/abi/linux/file.go b/pkg/abi/linux/file.go
index c9ee098f4..e11ca2d62 100644
--- a/pkg/abi/linux/file.go
+++ b/pkg/abi/linux/file.go
@@ -24,27 +24,23 @@ import (
 
 // Constants for open(2).
 const (
-	O_ACCMODE   = 000000003
-	O_RDONLY    = 000000000
-	O_WRONLY    = 000000001
-	O_RDWR      = 000000002
-	O_CREAT     = 000000100
-	O_EXCL      = 000000200
-	O_NOCTTY    = 000000400
-	O_TRUNC     = 000001000
-	O_APPEND    = 000002000
-	O_NONBLOCK  = 000004000
-	O_DSYNC     = 000010000
-	O_ASYNC     = 000020000
-	O_DIRECT    = 000040000
-	O_LARGEFILE = 000100000
-	O_DIRECTORY = 000200000
-	O_NOFOLLOW  = 000400000
-	O_NOATIME   = 001000000
-	O_CLOEXEC   = 002000000
-	O_SYNC      = 004000000 // __O_SYNC in Linux
-	O_PATH      = 010000000
-	O_TMPFILE   = 020000000 // __O_TMPFILE in Linux
+	O_ACCMODE  = 000000003
+	O_RDONLY   = 000000000
+	O_WRONLY   = 000000001
+	O_RDWR     = 000000002
+	O_CREAT    = 000000100
+	O_EXCL     = 000000200
+	O_NOCTTY   = 000000400
+	O_TRUNC    = 000001000
+	O_APPEND   = 000002000
+	O_NONBLOCK = 000004000
+	O_DSYNC    = 000010000
+	O_ASYNC    = 000020000
+	O_NOATIME  = 001000000
+	O_CLOEXEC  = 002000000
+	O_SYNC     = 004000000 // __O_SYNC in Linux
+	O_PATH     = 010000000
+	O_TMPFILE  = 020000000 // __O_TMPFILE in Linux
 )
 
 // Constants for fstatat(2).
@@ -144,9 +140,13 @@ const (
 	ModeCharacterDevice = S_IFCHR
 	ModeNamedPipe       = S_IFIFO
 
-	ModeSetUID = 04000
-	ModeSetGID = 02000
-	ModeSticky = 01000
+	S_ISUID = 04000
+	S_ISGID = 02000
+	S_ISVTX = 01000
+
+	ModeSetUID = S_ISUID
+	ModeSetGID = S_ISGID
+	ModeSticky = S_ISVTX
 
 	ModeUserAll     = 0700
 	ModeUserRead    = 0400
@@ -176,10 +176,24 @@ const (
 	DT_WHT     = 14
 )
 
+// DirentType are the friendly strings for linux_dirent64.d_type.
+var DirentType = abi.ValueSet{
+	DT_UNKNOWN: "DT_UNKNOWN",
+	DT_FIFO:    "DT_FIFO",
+	DT_CHR:     "DT_CHR",
+	DT_DIR:     "DT_DIR",
+	DT_BLK:     "DT_BLK",
+	DT_REG:     "DT_REG",
+	DT_LNK:     "DT_LNK",
+	DT_SOCK:    "DT_SOCK",
+	DT_WHT:     "DT_WHT",
+}
+
 // Values for preadv2/pwritev2.
 const (
-	// Note: gVisor does not implement the RWF_HIPRI feature, but the flag is
-	// accepted as a valid flag argument for preadv2/pwritev2.
+	// NOTE(b/120162627): gVisor does not implement the RWF_HIPRI feature, but
+	// the flag is accepted as a valid flag argument for preadv2/pwritev2 and
+	// silently ignored.
 	RWF_HIPRI = 0x00000001
 	RWF_DSYNC = 0x00000002
 	RWF_SYNC  = 0x00000004
@@ -228,6 +242,8 @@ const (
 )
 
 // Statx represents struct statx.
+//
+// +marshal
 type Statx struct {
 	Mask           uint32
 	Blksize        uint32
@@ -251,6 +267,9 @@ type Statx struct {
 	DevMinor       uint32
 }
 
+// SizeOfStatx is the size of a Statx struct.
+var SizeOfStatx = binary.Size(Statx{})
+
 // FileMode represents a mode_t.
 type FileMode uint16
 
@@ -269,6 +288,11 @@ func (m FileMode) ExtraBits() FileMode {
 	return m &^ (PermissionsMask | FileTypeMask)
 }
 
+// IsDir returns true if file type represents a directory.
+func (m FileMode) IsDir() bool {
+	return m.FileType() == S_IFDIR
+}
+
 // String returns a string representation of m.
 func (m FileMode) String() string {
 	var s []string
@@ -282,6 +306,29 @@ func (m FileMode) String() string {
 	return strings.Join(s, "|")
 }
 
+// DirentType maps file types to dirent types appropriate for (struct
+// dirent)::d_type.
+func (m FileMode) DirentType() uint8 {
+	switch m.FileType() {
+	case ModeSocket:
+		return DT_SOCK
+	case ModeSymlink:
+		return DT_LNK
+	case ModeRegular:
+		return DT_REG
+	case ModeBlockDevice:
+		return DT_BLK
+	case ModeDirectory:
+		return DT_DIR
+	case ModeCharacterDevice:
+		return DT_CHR
+	case ModeNamedPipe:
+		return DT_FIFO
+	default:
+		return DT_UNKNOWN
+	}
+}
+
 var modeExtraBits = abi.FlagSet{
 	{
 		Flag: ModeSetUID,