1 files changed, 24 insertions, 11 deletions

diff --git a/vendor/golang.org/x/net/ipv4/header.go b/vendor/golang.org/x/net/ipv4/header.go
index 8bb0f0f..a00a3ea 100644
--- a/vendor/golang.org/x/net/ipv4/header.go
+++ b/vendor/golang.org/x/net/ipv4/header.go
@@ -9,15 +9,13 @@ import (
 	"fmt"
 	"net"
 	"runtime"
-	"syscall"
 
 	"golang.org/x/net/internal/socket"
 )
 
 const (
-	Version      = 4  // protocol version
-	HeaderLen    = 20 // header length without extension headers
-	maxHeaderLen = 60 // sensible default, revisit if later RFCs define new usage of version and header length fields
+	Version   = 4  // protocol version
+	HeaderLen = 20 // header length without extension headers
 )
 
 type HeaderFlags int
@@ -52,9 +50,13 @@ func (h *Header) String() string {
 }
 
 // Marshal returns the binary encoding of h.
+//
+// The returned slice is in the format used by a raw IP socket on the
+// local system.
+// This may differ from the wire format, depending on the system.
 func (h *Header) Marshal() ([]byte, error) {
 	if h == nil {
-		return nil, syscall.EINVAL
+		return nil, errNilHeader
 	}
 	if h.Len < HeaderLen {
 		return nil, errHeaderTooShort
@@ -65,7 +67,7 @@ func (h *Header) Marshal() ([]byte, error) {
 	b[1] = byte(h.TOS)
 	flagsAndFragOff := (h.FragOff & 0x1fff) | int(h.Flags<<13)
 	switch runtime.GOOS {
-	case "darwin", "dragonfly", "netbsd":
+	case "darwin", "ios", "dragonfly", "netbsd":
 		socket.NativeEndian.PutUint16(b[2:4], uint16(h.TotalLen))
 		socket.NativeEndian.PutUint16(b[6:8], uint16(flagsAndFragOff))
 	case "freebsd":
@@ -98,14 +100,21 @@ func (h *Header) Marshal() ([]byte, error) {
 	return b, nil
 }
 
-// Parse parses b as an IPv4 header and sotres the result in h.
+// Parse parses b as an IPv4 header and stores the result in h.
+//
+// The provided b must be in the format used by a raw IP socket on the
+// local system.
+// This may differ from the wire format, depending on the system.
 func (h *Header) Parse(b []byte) error {
-	if h == nil || len(b) < HeaderLen {
+	if h == nil || b == nil {
+		return errNilHeader
+	}
+	if len(b) < HeaderLen {
 		return errHeaderTooShort
 	}
 	hdrlen := int(b[0]&0x0f) << 2
-	if hdrlen > len(b) {
-		return errBufferTooShort
+	if len(b) < hdrlen {
+		return errExtHeaderTooShort
 	}
 	h.Version = int(b[0] >> 4)
 	h.Len = hdrlen
@@ -117,7 +126,7 @@ func (h *Header) Parse(b []byte) error {
 	h.Src = net.IPv4(b[12], b[13], b[14], b[15])
 	h.Dst = net.IPv4(b[16], b[17], b[18], b[19])
 	switch runtime.GOOS {
-	case "darwin", "dragonfly", "netbsd":
+	case "darwin", "ios", "dragonfly", "netbsd":
 		h.TotalLen = int(socket.NativeEndian.Uint16(b[2:4])) + hdrlen
 		h.FragOff = int(socket.NativeEndian.Uint16(b[6:8]))
 	case "freebsd":
@@ -150,6 +159,10 @@ func (h *Header) Parse(b []byte) error {
 }
 
 // ParseHeader parses b as an IPv4 header.
+//
+// The provided b must be in the format used by a raw IP socket on the
+// local system.
+// This may differ from the wire format, depending on the system.
 func ParseHeader(b []byte) (*Header, error) {
 	h := new(Header)
 	if err := h.Parse(b); err != nil {