|  | // Copyright 2014 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 | 
|  |  | 
|  | // Sticky socket options | 
|  | const ( | 
|  | ssoTOS                = iota // header field for unicast packet | 
|  | ssoTTL                       // header field for unicast packet | 
|  | ssoMulticastTTL              // header field for multicast packet | 
|  | ssoMulticastInterface        // outbound interface for multicast packet | 
|  | ssoMulticastLoopback         // loopback for multicast packet | 
|  | ssoReceiveTTL                // header field on received packet | 
|  | ssoReceiveDst                // header field on received packet | 
|  | ssoReceiveInterface          // inbound interface on received packet | 
|  | ssoPacketInfo                // incbound or outbound packet path | 
|  | ssoHeaderPrepend             // ipv4 header prepend | 
|  | ssoStripHeader               // strip ipv4 header | 
|  | ssoICMPFilter                // icmp filter | 
|  | ssoJoinGroup                 // any-source multicast | 
|  | ssoLeaveGroup                // any-source multicast | 
|  | ssoJoinSourceGroup           // source-specific multicast | 
|  | ssoLeaveSourceGroup          // source-specific multicast | 
|  | ssoBlockSourceGroup          // any-source or source-specific multicast | 
|  | ssoUnblockSourceGroup        // any-source or source-specific multicast | 
|  | ssoMax | 
|  | ) | 
|  |  | 
|  | // Sticky socket option value types | 
|  | const ( | 
|  | ssoTypeByte = iota + 1 | 
|  | ssoTypeInt | 
|  | ssoTypeInterface | 
|  | ssoTypeICMPFilter | 
|  | ssoTypeIPMreq | 
|  | ssoTypeIPMreqn | 
|  | ssoTypeGroupReq | 
|  | ssoTypeGroupSourceReq | 
|  | ) | 
|  |  | 
|  | // A sockOpt represents a binding for sticky socket option. | 
|  | type sockOpt struct { | 
|  | name int // option name, must be equal or greater than 1 | 
|  | typ  int // option value type, must be equal or greater than 1 | 
|  | } |