Hulk did something

[bytom/vapor.git] / vendor / golang.org / x / net / ipv4 / packet.go

diff --git a/vendor/golang.org/x/net/ipv4/packet.go b/vendor/golang.org/x/net/ipv4/packet.go
new file mode 100644 (file)
index 0000000..f00f5b0
--- /dev/null
+++ b/vendor/golang.org/x/net/ipv4/packet.go
@@ -0,0 +1,69 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ipv4
+
+import (
+       "net"
+       "syscall"
+
+       "golang.org/x/net/internal/socket"
+)
+
+// BUG(mikio): On Windows, the ReadFrom and WriteTo methods of RawConn
+// are not implemented.
+
+// A packetHandler represents the IPv4 datagram handler.
+type packetHandler struct {
+       *net.IPConn
+       *socket.Conn
+       rawOpt
+}
+
+func (c *packetHandler) ok() bool { return c != nil && c.IPConn != nil && c.Conn != nil }
+
+// ReadFrom reads an IPv4 datagram from the endpoint c, copying the
+// datagram into b. It returns the received datagram as the IPv4
+// header h, the payload p and the control message cm.
+func (c *packetHandler) ReadFrom(b []byte) (h *Header, p []byte, cm *ControlMessage, err error) {
+       if !c.ok() {
+               return nil, nil, nil, syscall.EINVAL
+       }
+       return c.readFrom(b)
+}
+
+func slicePacket(b []byte) (h, p []byte, err error) {
+       if len(b) < HeaderLen {
+               return nil, nil, errHeaderTooShort
+       }
+       hdrlen := int(b[0]&0x0f) << 2
+       return b[:hdrlen], b[hdrlen:], nil
+}
+
+// WriteTo writes an IPv4 datagram through the endpoint c, copying the
+// datagram from the IPv4 header h and the payload p. The control
+// message cm allows the datagram path and the outgoing interface to be
+// specified.  Currently only Darwin and Linux support this. The cm
+// may be nil if control of the outgoing datagram is not required.
+//
+// The IPv4 header h must contain appropriate fields that include:
+//
+//     Version       = <must be specified>
+//     Len           = <must be specified>
+//     TOS           = <must be specified>
+//     TotalLen      = <must be specified>
+//     ID            = platform sets an appropriate value if ID is zero
+//     FragOff       = <must be specified>
+//     TTL           = <must be specified>
+//     Protocol      = <must be specified>
+//     Checksum      = platform sets an appropriate value if Checksum is zero
+//     Src           = platform sets an appropriate value if Src is nil
+//     Dst           = <must be specified>
+//     Options       = optional
+func (c *packetHandler) WriteTo(h *Header, p []byte, cm *ControlMessage) error {
+       if !c.ok() {
+               return syscall.EINVAL
+       }
+       return c.writeTo(h, p, cm)
+}