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
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/*
Copyright (c) 2012-2014, Matthias Schiffer <mschiffer@universe-factory.net>
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
\file
cipher-test method provider (testing and benchmarking only)
The cipher-test method provider performs encryption only and can be used to test
and benchmark cipher implementations.
*/
#include "../../crypto.h"
#include "../../method.h"
#include "../common.h"
/** A specific method provided by this provider */
struct fastd_method {
const fastd_cipher_info_t *cipher_info; /**< The cipher used */
};
/** The method-specific session state */
struct fastd_method_session_state {
fastd_method_common_t common; /**< The common method state */
const fastd_method_t *method; /**< The specific method used */
const fastd_cipher_t *cipher; /**< The cipher implementation used */
fastd_cipher_state_t *cipher_state; /**< The cipher state */
};
/** Instanciates a method using a name of the pattern "<cipher>+cipher-test" */
static bool method_create_by_name(const char *name, fastd_method_t **method) {
fastd_method_t m;
size_t len = strlen(name);
if (len < 12)
return false;
if (strcmp(name+len-12, "+cipher-test"))
return false;
char cipher_name[len-11];
memcpy(cipher_name, name, len-12);
cipher_name[len-12] = 0;
m.cipher_info = fastd_cipher_info_get_by_name(cipher_name);
if (!m.cipher_info)
return false;
*method = fastd_new(fastd_method_t);
**method = m;
return true;
}
/** Frees a method */
static void method_destroy(fastd_method_t *method) {
free(method);
}
/** Returns the key length used by a method */
static size_t method_key_length(const fastd_method_t *method) {
return method->cipher_info->key_length;
}
/** Initializes a session */
static fastd_method_session_state_t* method_session_init(const fastd_method_t *method, const uint8_t *secret, bool initiator) {
fastd_method_session_state_t *session = fastd_new(fastd_method_session_state_t);
fastd_method_common_init(&session->common, initiator);
session->method = method;
session->cipher = fastd_cipher_get(method->cipher_info);
session->cipher_state = session->cipher->init(secret);
pr_warn("using cipher-test method; this method must be used for testing and benchmarks only");
return session;
}
/** Checks if the session is currently valid */
static bool method_session_is_valid(fastd_method_session_state_t *session) {
return (session && fastd_method_session_common_is_valid(&session->common));
}
/** Checks if this side is the initator of the session */
static bool method_session_is_initiator(fastd_method_session_state_t *session) {
return fastd_method_session_common_is_initiator(&session->common);
}
/** Checks if the session should be refreshed */
static bool method_session_want_refresh(fastd_method_session_state_t *session) {
return fastd_method_session_common_want_refresh(&session->common);
}
/** Marks the session as superseded */
static void method_session_superseded(fastd_method_session_state_t *session) {
fastd_method_session_common_superseded(&session->common);
}
/** Frees the session state */
static void method_session_free(fastd_method_session_state_t *session) {
if (session) {
session->cipher->free(session->cipher_state);
free(session);
}
}
/** Encrypts a packet and adds the common method header */
static bool method_encrypt(fastd_peer_t *peer UNUSED, fastd_method_session_state_t *session, fastd_buffer_t *out, fastd_buffer_t in) {
size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len;
*out = fastd_buffer_alloc(in.len, alignto(COMMON_HEADBYTES, 16), sizeof(fastd_block128_t)+tail_len);
if (tail_len)
memset(in.data+in.len, 0, tail_len);
uint8_t nonce[session->method->cipher_info->iv_length] __attribute__((aligned(8)));
fastd_method_expand_nonce(nonce, session->common.send_nonce, sizeof(nonce));
int n_blocks = block_count(in.len, sizeof(fastd_block128_t));
fastd_block128_t *inblocks = in.data;
fastd_block128_t *outblocks = out->data;
bool ok = session->cipher->crypt(session->cipher_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), nonce);
if (!ok) {
fastd_buffer_free(*out);
return false;
}
fastd_buffer_free(in);
fastd_method_put_common_header(out, session->common.send_nonce, 0);
fastd_method_increment_nonce(&session->common);
return true;
}
/** Decrypts a packet */
static bool method_decrypt(fastd_peer_t *peer, fastd_method_session_state_t *session, fastd_buffer_t *out, fastd_buffer_t in) {
if (in.len < COMMON_HEADBYTES)
return false;
if (!method_session_is_valid(session))
return false;
uint8_t in_nonce[COMMON_NONCEBYTES];
uint8_t flags;
int64_t age;
if (!fastd_method_handle_common_header(&session->common, &in, in_nonce, &flags, &age))
return false;
if (flags)
return false;
uint8_t nonce[session->method->cipher_info->iv_length] __attribute__((aligned(8)));
fastd_method_expand_nonce(nonce, in_nonce, sizeof(nonce));
size_t tail_len = alignto(in.len, sizeof(fastd_block128_t))-in.len;
*out = fastd_buffer_alloc(in.len, 0, tail_len);
int n_blocks = block_count(in.len, sizeof(fastd_block128_t));
fastd_block128_t *inblocks = in.data;
fastd_block128_t *outblocks = out->data;
bool ok = session->cipher->crypt(session->cipher_state, outblocks, inblocks, n_blocks*sizeof(fastd_block128_t), nonce);
if (!ok) {
fastd_buffer_free(*out);
return false;
}
if (!fastd_method_reorder_check(peer, &session->common, in_nonce, age)) {
fastd_buffer_free(*out);
*out = fastd_buffer_alloc(0, 0, 0);
}
fastd_buffer_free(in);
return true;
}
/** The cipher-test method provider */
const fastd_method_provider_t fastd_method_cipher_test = {
.max_overhead = COMMON_HEADBYTES,
.min_encrypt_head_space = 0,
.min_decrypt_head_space = 0,
.min_encrypt_tail_space = sizeof(fastd_block128_t)-1,
.min_decrypt_tail_space = sizeof(fastd_block128_t)-1,
.create_by_name = method_create_by_name,
.destroy = method_destroy,
.key_length = method_key_length,
.session_init = method_session_init,
.session_is_valid = method_session_is_valid,
.session_is_initiator = method_session_is_initiator,
.session_want_refresh = method_session_want_refresh,
.session_superseded = method_session_superseded,
.session_free = method_session_free,
.encrypt = method_encrypt,
.decrypt = method_decrypt,
};
|
