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_ctr_init(br_aes_ct_ctr_keys
*ctx
,
30 const void *key
, size_t len
)
32 ctx
->vtable
= &br_aes_ct_ctr_vtable
;
33 ctx
->num_rounds
= br_aes_ct_keysched(ctx
->skey
, key
, len
);
37 xorbuf(void *dst
, const void *src
, size_t len
)
40 const unsigned char *s
;
49 /* see bearssl_block.h */
51 br_aes_ct_ctr_run(const br_aes_ct_ctr_keys
*ctx
,
52 const void *iv
, uint32_t cc
, void *data
, size_t len
)
55 const unsigned char *ivbuf
;
56 uint32_t iv0
, iv1
, iv2
;
59 br_aes_ct_skey_expand(sk_exp
, ctx
->num_rounds
, ctx
->skey
);
61 iv0
= br_dec32le(ivbuf
);
62 iv1
= br_dec32le(ivbuf
+ 4);
63 iv2
= br_dec32le(ivbuf
+ 8);
67 unsigned char tmp
[32];
70 * TODO: see if we can save on the first br_aes_ct_ortho()
71 * call, since iv0/iv1/iv2 are constant for the whole run.
77 q
[7] = br_swap32(cc
+ 1);
79 br_aes_ct_bitslice_encrypt(ctx
->num_rounds
, sk_exp
, q
);
81 br_enc32le(tmp
, q
[0]);
82 br_enc32le(tmp
+ 4, q
[2]);
83 br_enc32le(tmp
+ 8, q
[4]);
84 br_enc32le(tmp
+ 12, q
[6]);
85 br_enc32le(tmp
+ 16, q
[1]);
86 br_enc32le(tmp
+ 20, q
[3]);
87 br_enc32le(tmp
+ 24, q
[5]);
88 br_enc32le(tmp
+ 28, q
[7]);
91 xorbuf(buf
, tmp
, len
);
106 /* see bearssl_block.h */
107 const br_block_ctr_class br_aes_ct_ctr_vtable
= {
108 sizeof(br_aes_ct_ctr_keys
),
111 (void (*)(const br_block_ctr_class
**, const void *, size_t))
113 (uint32_t (*)(const br_block_ctr_class
*const *,
114 const void *, uint32_t, void *, size_t))