1*0957b409SSimon J. Gerraty /*
2*0957b409SSimon J. Gerraty * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
3*0957b409SSimon J. Gerraty *
4*0957b409SSimon J. Gerraty * Permission is hereby granted, free of charge, to any person obtaining
5*0957b409SSimon J. Gerraty * a copy of this software and associated documentation files (the
6*0957b409SSimon J. Gerraty * "Software"), to deal in the Software without restriction, including
7*0957b409SSimon J. Gerraty * without limitation the rights to use, copy, modify, merge, publish,
8*0957b409SSimon J. Gerraty * distribute, sublicense, and/or sell copies of the Software, and to
9*0957b409SSimon J. Gerraty * permit persons to whom the Software is furnished to do so, subject to
10*0957b409SSimon J. Gerraty * the following conditions:
11*0957b409SSimon J. Gerraty *
12*0957b409SSimon J. Gerraty * The above copyright notice and this permission notice shall be
13*0957b409SSimon J. Gerraty * included in all copies or substantial portions of the Software.
14*0957b409SSimon J. Gerraty *
15*0957b409SSimon J. Gerraty * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16*0957b409SSimon J. Gerraty * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17*0957b409SSimon J. Gerraty * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18*0957b409SSimon J. Gerraty * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19*0957b409SSimon J. Gerraty * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20*0957b409SSimon J. Gerraty * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21*0957b409SSimon J. Gerraty * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22*0957b409SSimon J. Gerraty * SOFTWARE.
23*0957b409SSimon J. Gerraty */
24*0957b409SSimon J. Gerraty
25*0957b409SSimon J. Gerraty #include "inner.h"
26*0957b409SSimon J. Gerraty
27*0957b409SSimon J. Gerraty /* see inner.h */
28*0957b409SSimon J. Gerraty void
br_ecdsa_i31_bits2int(uint32_t * x,const void * src,size_t len,uint32_t ebitlen)29*0957b409SSimon J. Gerraty br_ecdsa_i31_bits2int(uint32_t *x,
30*0957b409SSimon J. Gerraty const void *src, size_t len, uint32_t ebitlen)
31*0957b409SSimon J. Gerraty {
32*0957b409SSimon J. Gerraty uint32_t bitlen, hbitlen;
33*0957b409SSimon J. Gerraty int sc;
34*0957b409SSimon J. Gerraty
35*0957b409SSimon J. Gerraty bitlen = ebitlen - (ebitlen >> 5);
36*0957b409SSimon J. Gerraty hbitlen = (uint32_t)len << 3;
37*0957b409SSimon J. Gerraty if (hbitlen > bitlen) {
38*0957b409SSimon J. Gerraty len = (bitlen + 7) >> 3;
39*0957b409SSimon J. Gerraty sc = (int)((hbitlen - bitlen) & 7);
40*0957b409SSimon J. Gerraty } else {
41*0957b409SSimon J. Gerraty sc = 0;
42*0957b409SSimon J. Gerraty }
43*0957b409SSimon J. Gerraty br_i31_zero(x, ebitlen);
44*0957b409SSimon J. Gerraty br_i31_decode(x, src, len);
45*0957b409SSimon J. Gerraty br_i31_rshift(x, sc);
46*0957b409SSimon J. Gerraty x[0] = ebitlen;
47*0957b409SSimon J. Gerraty }
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