summaryrefslogtreecommitdiff
path: root/src/cipher.c
blob: b3a8480a46e795b6388efffe0cc44cc6d749deb5 (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
169
170
171
172
173
174
175
176
177
178
179
/*
 *  �Anytun
 *
 *  �Anytun is a tiny implementation of SATP. Unlike Anytun which is a full
 *  featured implementation �Anytun has no support for multiple connections
 *  or synchronisation. It is a small single threaded implementation intended
 *  to act as a client on small platforms.
 *  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) 2007-2008 Christian Pointner <equinox@anytun.org>
 *
 *  This file is part of �Anytun.
 *
 *  �Anytun is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 3 as
 *  published by the Free Software Foundation.
 *
 *  �Anytun 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 �Anytun. If not, see <http://www.gnu.org/licenses/>.
 */

#include "datatypes.h"

#include "plain_packet.h"
#include "encrypted_packet.h"

#include "cipher.h"

#include "log.h"

#include <stdlib.h>
#include <string.h>

void cipher_init(cipher_t** c, const char* type)
{
  if(!c) 
    return;

  *c = malloc(sizeof(cipher_t));
  if(!*c)
    return;

  (*c)->type_ = unknown;
  if(!strcmp(type, "null"))
    (*c)->type_ = null;
/*   else if(!strcmp(type, "aes-ctr")) */
/*     (*c)->type_ = aes_ctr; */
  else {
    log_printf(ERR, "unknown cipher type");
  }

  (*c)->key_.buf_ = NULL;
  (*c)->key_.length_ = 0;

  (*c)->salt_.buf_ = NULL;
  (*c)->salt_.length_ = 0;
}

void cipher_set_key(cipher_t* c, u_int8_t* key, u_int32_t len)
{
  if(!c) 
    return;
  if(c->type_ == null)
    return;

  if(c->key_.buf_)
    free(c->key_.buf_);
  c->key_.buf_ = malloc(len);
  if(!c->key_.buf_) {
    c->key_.length_ = 0;
    return;
  }
  memcpy(c->key_.buf_, key, len);
  c->key_.length_ = len;
}

void cipher_set_salt(cipher_t* c, u_int8_t* salt, u_int32_t len)
{
  if(!c) 
    return;
  if(c->type_ == null)
    return;

  if(c->salt_.buf_)
    free(c->salt_.buf_);
  c->salt_.buf_ = malloc(len);
  if(!c->salt_.buf_) {
    c->salt_.length_ = 0;
    return;
  }
  memcpy(c->salt_.buf_, salt, len);
  c->salt_.length_ = len;
}

void cipher_close(cipher_t** c)
{
  if(!c || !(*c))
    return;

  if((*c)->key_.buf_)
    free((*c)->key_.buf_);
  if((*c)->salt_.buf_)
    free((*c)->salt_.buf_);

  free(*c);
  *c = NULL;
}

void cipher_encrypt(cipher_t* c, plain_packet_t* in, encrypted_packet_t* out, seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux)
{
  if(!c) 
    return;

	u_int32_t len;
  if(c->type_ = null)
    len = cipher_null_encrypt(plain_packet_get_packet(in), plain_packet_get_length(in), 
                              encrypted_packet_get_payload(out), encrypted_packet_get_payload_length(out));
/*   else if(c->type_ = aes_ctr) */
/*     len = cipher_aesctr_encrypt(plain_packet_get_packet(in), plain_packet_get_length(in),  */
/*                                 encrypted_packet_get_payload(out), encrypted_packet_get_payload_length(out), */
/*                                 seq_nr, sender_id, mux); */
  else {
    log_printf(ERR, "unknown cipher type");
    return;
  }

	encrypted_packet_set_sender_id(out, sender_id);
  encrypted_packet_set_seq_nr(out, seq_nr);
  encrypted_packet_set_mux(out, mux);

  encrypted_packet_set_payload_length(out, len);
}

void cipher_decrypt(cipher_t* c, encrypted_packet_t* in, plain_packet_t* out)
{
  if(!c) 
    return;

	u_int32_t len;
  if(c->type_ = null)
    len = cipher_null_decrypt(encrypted_packet_get_payload(in), encrypted_packet_get_payload_length(in),
                              plain_packet_get_packet(out), plain_packet_get_length(out));
/*   else if(c->type_ = aes_ctr) */
/*     len = cipher_aesctr_decrypt(encrypted_packet_get_payload(in), encrypted_packet_get_payload_length(in), */
/*                                 plain_packet_get_packet(out), plain_packet_get_length(out),  */
/*                                 encrypted_packet_get_seq_nr(in), encrypted_packet_get_sender_id(in),  */
/*                                 encrypted_packet_get_mux(in)); */
  else {
    log_printf(ERR, "unknown cipher type");
    return;
  }
  
	plain_packet_set_length(out, len);
}

u_int32_t cipher_null_encrypt(u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen)
{
	memcpy(out, in, (ilen < olen) ? ilen : olen);
  return (ilen < olen) ? ilen : olen;
}

u_int32_t cipher_null_decrypt(u_int8_t* in, u_int32_t ilen, u_int8_t* out, u_int32_t olen)
{
	memcpy(out, in, (ilen < olen) ? ilen : olen);
  return (ilen < olen) ? ilen : olen;
}