1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2010 Hajime Tazaki
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation;
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
17  *
18  * Authors: Hajime Tazaki <tazaki@sfc.wide.ad.jp>
19  */
20 
21 #ifndef IPV4_PACKET_INFO_TAG_H
22 #define IPV4_PACKET_INFO_TAG_H
23 
24 #include "ns3/tag.h"
25 #include "ns3/ipv4-address.h"
26 
27 namespace ns3 {
28 
29 
30 class Node;
31 class Packet;
32 
33 /**
34  * \ingroup ipv4
35  *
36  * \brief This class implements Linux struct pktinfo
37  * in order to deliver ancillary information to the socket interface.
38  * This is used with socket option such as IP_PKTINFO, IP_RECVTTL,
39  * IP_RECVTOS. See linux manpage ip(7).
40  *
41  * See also SocketIpTosTag and SocketIpTtlTag
42  *
43  * The Tag does not carry the Local address (as it is not currently
44  * used to force a source address).
45  *
46  * This tag in the send direction is presently not enabled but we
47  * would accept a patch along those lines in the future.
48  */
49 class Ipv4PacketInfoTag : public Tag
50 {
51 public:
52   Ipv4PacketInfoTag ();
53 
54   /**
55    * \brief Set the tag's address
56    *
57    * \param addr the address
58    */
59   void SetAddress (Ipv4Address addr);
60 
61   /**
62    * \brief Get the tag's address
63    *
64    * \returns the address
65    */
66   Ipv4Address GetAddress (void) const;
67 
68   /**
69    * \brief Set the tag's receiving interface
70    *
71    * \param ifindex the interface index
72    */
73   void SetRecvIf (uint32_t ifindex);
74   /**
75    * \brief Get the tag's receiving interface
76    *
77    * \returns the interface index
78    */
79   uint32_t GetRecvIf (void) const;
80 
81   /**
82    * \brief Set the tag's Time to Live
83    * Implemented, but not used in the stack yet
84    * \param ttl the TTL
85    */
86   void SetTtl (uint8_t ttl);
87   /**
88    * \brief Get the tag's Time to Live
89    * Implemented, but not used in the stack yet
90    * \returns the TTL
91    */
92   uint8_t GetTtl (void) const;
93 
94   /**
95    * \brief Get the type ID.
96    * \return the object TypeId
97    */
98   static TypeId GetTypeId (void);
99   virtual TypeId GetInstanceTypeId (void) const;
100   virtual uint32_t GetSerializedSize (void) const;
101   virtual void Serialize (TagBuffer i) const;
102   virtual void Deserialize (TagBuffer i);
103   virtual void Print (std::ostream &os) const;
104 
105 private:
106   // Linux IP_PKTINFO ip(7) implementation
107   //
108   // struct in_pktinfo {
109   //   unsigned int   ipi_ifindex;  /* Interface index */
110   //   struct in_addr ipi_spec_dst; /* Local address */
111   //   struct in_addr ipi_addr;     /* Header Destination
112   //                                   address */
113   // };
114 
115   Ipv4Address m_addr;     //!< Header destination address
116   uint32_t m_ifindex;     //!< interface index
117 
118   // Used for IP_RECVTTL, though not implemented yet.
119   uint8_t m_ttl; //!< Time to Live
120 };
121 } // namespace ns3
122 
123 #endif /* IPV4_PACKET_INFO_TAG_H */
124