summaryrefslogtreecommitdiff
path: root/src/plainPacket.cpp
blob: c4717c361916ab41da396d6339c92f3cb3991131 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
/*
 *  anytun
 *
 *  The secure anycast tunneling protocol (satp) defines a protocol used
 *  for communication between any combination of unicast and anycast
 *  tunnel endpoints.  It has less protocol overhead than IPSec in Tunnel
 *  mode and allows tunneling of every ETHER TYPE protocol (e.g.
 *  ethernet, ip, arp ...). satp directly includes cryptography and
 *  message authentication based on the methodes used by SRTP.  It is
 *  intended to deliver a generic, scaleable and secure solution for
 *  tunneling and relaying of packets of any protocol.
 *
 *
 *  Copyright (C) 2007 anytun.org <satp@wirdorange.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program (see the file COPYING included with this
 *  distribution); if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <stdexcept>
#include <iostream>
#include <arpa/inet.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>

#include "datatypes.h"
#include "plainPacket.h"

PlainPacket::PlainPacket(u_int32_t payload_length, bool allow_realloc) : Buffer(payload_length + sizeof(payload_type_t), allow_realloc)
{
  payload_type_ = reinterpret_cast<payload_type_t*>(buf_);
  payload_ = buf_ + sizeof(payload_type_t);
  *payload_type_ = 0;
}

payload_type_t PlainPacket::getPayloadType() const
{
  if(payload_type_)
    return PAYLOAD_TYPE_T_NTOH(*payload_type_);

  return 0;
}

void PlainPacket::setPayloadType(payload_type_t payload_type)
{
  if(!payload_type_)
    return;
  
  if(payload_type == PAYLOAD_TYPE_TUN) {
    if(!payload_) {
      *payload_type_ = PAYLOAD_TYPE_T_HTON(PAYLOAD_TYPE_TUN);
      return;
    }

    struct ip* hdr = reinterpret_cast<struct ip*>(payload_);
    if(hdr->ip_v == 4)
      *payload_type_ = PAYLOAD_TYPE_T_HTON(PAYLOAD_TYPE_TUN4);
    else if(hdr->ip_v == 6)
      *payload_type_ = PAYLOAD_TYPE_T_HTON(PAYLOAD_TYPE_TUN6);
  }
  else
    *payload_type_ = PAYLOAD_TYPE_T_HTON(payload_type);
}

u_int32_t PlainPacket::getPayloadLength() const
{
  if(!payload_)
    return 0;

  return (length_ > sizeof(payload_type_t)) ? (length_ - sizeof(payload_type_t)) : 0;
}
    
void PlainPacket::setPayloadLength(u_int32_t payload_length)
{
  Buffer::setLength(payload_length + sizeof(payload_type_t));
      // depending on allow_realloc buf_ may point to another address
      // therefore in this case reinit() gets called by Buffer::setLength()
}

void PlainPacket::reinit()
{
  payload_type_ = reinterpret_cast<payload_type_t*>(buf_);
  payload_ = buf_ + sizeof(payload_type_t);

  if(length_ <= (sizeof(payload_type_t)))
    payload_ = NULL;

  if(length_ < (sizeof(payload_type_t))) {
    payload_type_ = NULL;
    throw std::runtime_error("packet can't be initialized, buffer is too small"); 
  }

}

u_int8_t* PlainPacket::getPayload()
{
  return payload_;
}

NetworkAddress PlainPacket::getSrcAddr() const
{
  if(!payload_type_ || !payload_)
    return NetworkAddress();

  payload_type_t type = PAYLOAD_TYPE_T_NTOH(*payload_type_);

  if(type == PAYLOAD_TYPE_TAP) // Ehternet
  {
        // TODO
    return NetworkAddress();
  }
  else if(type == PAYLOAD_TYPE_TUN4) // IPv4
  {
    if(length_ < (sizeof(payload_type_t)+sizeof(struct ip)))
      return NetworkAddress();
    struct ip* hdr = reinterpret_cast<struct ip*>(payload_);
    return NetworkAddress(hdr->ip_src);
  }
  else if(type == PAYLOAD_TYPE_TUN6) // IPv6
  {
    if(length_ < (sizeof(payload_type_t)+sizeof(struct ip6_hdr)))
      return NetworkAddress();
    struct ip6_hdr* hdr = reinterpret_cast<struct ip6_hdr*>(payload_);
    return NetworkAddress(hdr->ip6_src);
  }
  return NetworkAddress();
}

NetworkAddress PlainPacket::getDstAddr() const
{
  if(!payload_type_ || !payload_)
    return NetworkAddress();

  payload_type_t type = PAYLOAD_TYPE_T_NTOH(*payload_type_);

  if(type == PAYLOAD_TYPE_TAP) // Ehternet
  {
        // TODO
    return NetworkAddress();
  }
  else if(type == PAYLOAD_TYPE_TUN4) // IPv4
  {
    if(length_ < (sizeof(payload_type_t)+sizeof(struct ip)))
      return NetworkAddress();
    struct ip* hdr = reinterpret_cast<struct ip*>(payload_);
    return NetworkAddress(hdr->ip_dst);
  }
  else if(type == PAYLOAD_TYPE_TUN6) // IPv6
  {
    if(length_ < (sizeof(payload_type_t)+sizeof(struct ip6_hdr)))
      return NetworkAddress();
    struct ip6_hdr* hdr = reinterpret_cast<struct ip6_hdr*>(payload_);
    return NetworkAddress(hdr->ip6_dst);
  }
  return NetworkAddress();
}