From 621e49bb465f500cc46d47e39e828cf76d6381d7 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Tue, 24 Jul 2018 14:35:44 +0200 Subject: update vendor --- vendor/golang.org/x/net/ipv4/control.go | 144 ++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 vendor/golang.org/x/net/ipv4/control.go (limited to 'vendor/golang.org/x/net/ipv4/control.go') diff --git a/vendor/golang.org/x/net/ipv4/control.go b/vendor/golang.org/x/net/ipv4/control.go new file mode 100644 index 0000000..a2b02ca --- /dev/null +++ b/vendor/golang.org/x/net/ipv4/control.go @@ -0,0 +1,144 @@ +// 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 ( + "fmt" + "net" + "sync" + + "golang.org/x/net/internal/iana" + "golang.org/x/net/internal/socket" +) + +type rawOpt struct { + sync.RWMutex + cflags ControlFlags +} + +func (c *rawOpt) set(f ControlFlags) { c.cflags |= f } +func (c *rawOpt) clear(f ControlFlags) { c.cflags &^= f } +func (c *rawOpt) isset(f ControlFlags) bool { return c.cflags&f != 0 } + +type ControlFlags uint + +const ( + FlagTTL ControlFlags = 1 << iota // pass the TTL on the received packet + FlagSrc // pass the source address on the received packet + FlagDst // pass the destination address on the received packet + FlagInterface // pass the interface index on the received packet +) + +// A ControlMessage represents per packet basis IP-level socket options. +type ControlMessage struct { + // Receiving socket options: SetControlMessage allows to + // receive the options from the protocol stack using ReadFrom + // method of PacketConn or RawConn. + // + // Specifying socket options: ControlMessage for WriteTo + // method of PacketConn or RawConn allows to send the options + // to the protocol stack. + // + TTL int // time-to-live, receiving only + Src net.IP // source address, specifying only + Dst net.IP // destination address, receiving only + IfIndex int // interface index, must be 1 <= value when specifying +} + +func (cm *ControlMessage) String() string { + if cm == nil { + return "" + } + return fmt.Sprintf("ttl=%d src=%v dst=%v ifindex=%d", cm.TTL, cm.Src, cm.Dst, cm.IfIndex) +} + +// Marshal returns the binary encoding of cm. +func (cm *ControlMessage) Marshal() []byte { + if cm == nil { + return nil + } + var m socket.ControlMessage + if ctlOpts[ctlPacketInfo].name > 0 && (cm.Src.To4() != nil || cm.IfIndex > 0) { + m = socket.NewControlMessage([]int{ctlOpts[ctlPacketInfo].length}) + } + if len(m) > 0 { + ctlOpts[ctlPacketInfo].marshal(m, cm) + } + return m +} + +// Parse parses b as a control message and stores the result in cm. +func (cm *ControlMessage) Parse(b []byte) error { + ms, err := socket.ControlMessage(b).Parse() + if err != nil { + return err + } + for _, m := range ms { + lvl, typ, l, err := m.ParseHeader() + if err != nil { + return err + } + if lvl != iana.ProtocolIP { + continue + } + switch { + case typ == ctlOpts[ctlTTL].name && l >= ctlOpts[ctlTTL].length: + ctlOpts[ctlTTL].parse(cm, m.Data(l)) + case typ == ctlOpts[ctlDst].name && l >= ctlOpts[ctlDst].length: + ctlOpts[ctlDst].parse(cm, m.Data(l)) + case typ == ctlOpts[ctlInterface].name && l >= ctlOpts[ctlInterface].length: + ctlOpts[ctlInterface].parse(cm, m.Data(l)) + case typ == ctlOpts[ctlPacketInfo].name && l >= ctlOpts[ctlPacketInfo].length: + ctlOpts[ctlPacketInfo].parse(cm, m.Data(l)) + } + } + return nil +} + +// NewControlMessage returns a new control message. +// +// The returned message is large enough for options specified by cf. +func NewControlMessage(cf ControlFlags) []byte { + opt := rawOpt{cflags: cf} + var l int + if opt.isset(FlagTTL) && ctlOpts[ctlTTL].name > 0 { + l += socket.ControlMessageSpace(ctlOpts[ctlTTL].length) + } + if ctlOpts[ctlPacketInfo].name > 0 { + if opt.isset(FlagSrc | FlagDst | FlagInterface) { + l += socket.ControlMessageSpace(ctlOpts[ctlPacketInfo].length) + } + } else { + if opt.isset(FlagDst) && ctlOpts[ctlDst].name > 0 { + l += socket.ControlMessageSpace(ctlOpts[ctlDst].length) + } + if opt.isset(FlagInterface) && ctlOpts[ctlInterface].name > 0 { + l += socket.ControlMessageSpace(ctlOpts[ctlInterface].length) + } + } + var b []byte + if l > 0 { + b = make([]byte, l) + } + return b +} + +// Ancillary data socket options +const ( + ctlTTL = iota // header field + ctlSrc // header field + ctlDst // header field + ctlInterface // inbound or outbound interface + ctlPacketInfo // inbound or outbound packet path + ctlMax +) + +// A ctlOpt represents a binding for ancillary data socket option. +type ctlOpt struct { + name int // option name, must be equal or greater than 1 + length int // option length + marshal func([]byte, *ControlMessage) []byte + parse func(*ControlMessage, []byte) +} -- cgit v1.2.3