aboutsummaryrefslogtreecommitdiffstats
path: root/src/libcharon/encoding/payloads/nonce_payload.c
blob: 52b09b663e4b7e7bdf64a0aa14fcb69f13038c2d (plain)
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
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
/*
 * Copyright (C) 2005-2010 Martin Willi
 * Copyright (C) 2010 revosec AG
 * Copyright (C) 2005 Jan Hutter
 * Hochschule fuer Technik Rapperswil
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
 *
 * 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.
 */

#include <stddef.h>

#include "nonce_payload.h"

#include <daemon.h>
#include <encoding/payloads/encodings.h>

typedef struct private_nonce_payload_t private_nonce_payload_t;

/**
 * Private data of an nonce_payload_t object.
 */
struct private_nonce_payload_t {

	/**
	 * Public nonce_payload_t interface.
	 */
	nonce_payload_t public;

	/**
	 * Next payload type.
	 */
	uint8_t  next_payload;

	/**
	 * Critical flag.
	 */
	bool critical;

	/**
	 * Reserved bits
	 */
	bool reserved[7];

	/**
	 * Length of this payload.
	 */
	uint16_t payload_length;

	/**
	 * The contained nonce value.
	 */
	chunk_t nonce;

	/**
	 * Payload type, PLV2_NONCE or PLV1_NONCE
	 */
	payload_type_t type;
};

/**
 * Encoding rules to parse or generate a nonce payload
 *
 * The defined offsets are the positions in a object of type
 * private_nonce_payload_t.
 */
static encoding_rule_t encodings[] = {
	/* 1 Byte next payload type, stored in the field next_payload */
	{ U_INT_8,			offsetof(private_nonce_payload_t, next_payload)		},
	/* the critical bit */
	{ FLAG,				offsetof(private_nonce_payload_t, critical)			},
	/* 7 Bit reserved bits */
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[0])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[1])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[2])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[3])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[4])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[5])		},
	{ RESERVED_BIT,		offsetof(private_nonce_payload_t, reserved[6])		},
	/* Length of the whole nonce payload*/
	{ PAYLOAD_LENGTH,	offsetof(private_nonce_payload_t, payload_length)	},
	/* some nonce bytes, length is defined in PAYLOAD_LENGTH */
	{ CHUNK_DATA,		offsetof(private_nonce_payload_t, nonce)			},
};

/*                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      ! Next Payload  !C!  RESERVED   !         Payload Length        !
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      !                                                               !
      ~                            Nonce Data                         ~
      !                                                               !
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/

METHOD(payload_t, verify, status_t,
	private_nonce_payload_t *this)
{
	bool bad_length = FALSE;

	if (this->nonce.len > 256)
	{
		bad_length = TRUE;
	}
	if (this->type == PLV2_NONCE &&
		this->nonce.len < 16)
	{
		bad_length = TRUE;
	}
	if (this->type == PLV1_NONCE &&
		this->nonce.len < 8)
	{
		bad_length = TRUE;
	}
	if (bad_length)
	{
		DBG1(DBG_ENC, "%N payload has invalid length (%d bytes)",
			 payload_type_names, this->type, this->nonce.len);
		return FAILED;
	}
	return SUCCESS;
}

METHOD(payload_t, get_encoding_rules, int,
	private_nonce_payload_t *this, encoding_rule_t **rules)
{
	*rules = encodings;
	return countof(encodings);
}

METHOD(payload_t, get_header_length, int,
	private_nonce_payload_t *this)
{
	return 4;
}

METHOD(payload_t, get_type, payload_type_t,
	private_nonce_payload_t *this)
{
	return this->type;
}

METHOD(payload_t, get_next_type, payload_type_t,
	private_nonce_payload_t *this)
{
	return this->next_payload;
}

METHOD(payload_t, set_next_type, void,
	private_nonce_payload_t *this, payload_type_t type)
{
	this->next_payload = type;
}

METHOD(payload_t, get_length, size_t,
	private_nonce_payload_t *this)
{
	return this->payload_length;
}

METHOD(nonce_payload_t, set_nonce, void,
	 private_nonce_payload_t *this, chunk_t nonce)
{
	this->nonce = chunk_clone(nonce);
	this->payload_length = get_header_length(this) + nonce.len;
}

METHOD(nonce_payload_t, get_nonce, chunk_t,
	private_nonce_payload_t *this)
{
	return chunk_clone(this->nonce);
}

METHOD2(payload_t, nonce_payload_t, destroy, void,
	private_nonce_payload_t *this)
{
	free(this->nonce.ptr);
	free(this);
}

/*
 * Described in header
 */
nonce_payload_t *nonce_payload_create(payload_type_t type)
{
	private_nonce_payload_t *this;

	INIT(this,
		.public = {
			.payload_interface = {
				.verify = _verify,
				.get_encoding_rules = _get_encoding_rules,
				.get_header_length = _get_header_length,
				.get_length = _get_length,
				.get_next_type = _get_next_type,
				.set_next_type = _set_next_type,
				.get_type = _get_type,
				.destroy = _destroy,
			},
			.set_nonce = _set_nonce,
			.get_nonce = _get_nonce,
			.destroy = _destroy,
		},
		.next_payload = PL_NONE,
		.payload_length = get_header_length(this),
		.type = type,
	);
	return &this->public;
}