2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
27 /* see bearssl_block.h */
29 br_aes_ct_cbcdec_init(br_aes_ct_cbcdec_keys
*ctx
,
30 const void *key
, size_t len
)
32 ctx
->vtable
= &br_aes_ct_cbcdec_vtable
;
33 ctx
->num_rounds
= br_aes_ct_keysched(ctx
->skey
, key
, len
);
36 /* see bearssl_block.h */
38 br_aes_ct_cbcdec_run(const br_aes_ct_cbcdec_keys
*ctx
,
39 void *iv
, void *data
, size_t len
)
41 unsigned char *buf
, *ivbuf
;
42 uint32_t iv0
, iv1
, iv2
, iv3
;
45 br_aes_ct_skey_expand(sk_exp
, ctx
->num_rounds
, ctx
->skey
);
47 iv0
= br_dec32le(ivbuf
);
48 iv1
= br_dec32le(ivbuf
+ 4);
49 iv2
= br_dec32le(ivbuf
+ 8);
50 iv3
= br_dec32le(ivbuf
+ 12);
55 q
[0] = br_dec32le(buf
);
56 q
[2] = br_dec32le(buf
+ 4);
57 q
[4] = br_dec32le(buf
+ 8);
58 q
[6] = br_dec32le(buf
+ 12);
60 q
[1] = br_dec32le(buf
+ 16);
61 q
[3] = br_dec32le(buf
+ 20);
62 q
[5] = br_dec32le(buf
+ 24);
63 q
[7] = br_dec32le(buf
+ 28);
70 memcpy(sq
, q
, sizeof q
);
72 br_aes_ct_bitslice_decrypt(ctx
->num_rounds
, sk_exp
, q
);
74 br_enc32le(buf
, q
[0] ^ iv0
);
75 br_enc32le(buf
+ 4, q
[2] ^ iv1
);
76 br_enc32le(buf
+ 8, q
[4] ^ iv2
);
77 br_enc32le(buf
+ 12, q
[6] ^ iv3
);
85 br_enc32le(buf
+ 16, q
[1] ^ sq
[0]);
86 br_enc32le(buf
+ 20, q
[3] ^ sq
[2]);
87 br_enc32le(buf
+ 24, q
[5] ^ sq
[4]);
88 br_enc32le(buf
+ 28, q
[7] ^ sq
[6]);
96 br_enc32le(ivbuf
, iv0
);
97 br_enc32le(ivbuf
+ 4, iv1
);
98 br_enc32le(ivbuf
+ 8, iv2
);
99 br_enc32le(ivbuf
+ 12, iv3
);
102 /* see bearssl_block.h */
103 const br_block_cbcdec_class br_aes_ct_cbcdec_vtable
= {
104 sizeof(br_aes_ct_cbcdec_keys
),
107 (void (*)(const br_block_cbcdec_class
**, const void *, size_t))
108 &br_aes_ct_cbcdec_init
,
109 (void (*)(const br_block_cbcdec_class
*const *, void *, void *, size_t))
110 &br_aes_ct_cbcdec_run