1 /* fp_mul_comba_8.i
2  *
3  * Copyright (C) 2006-2021 wolfSSL Inc.
4  *
5  * This file is part of wolfSSL.
6  *
7  * wolfSSL is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * wolfSSL is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
20  */
21 
22 
23 
24 #ifdef TFM_MUL8
fp_mul_comba8(fp_int * A,fp_int * B,fp_int * C)25 int fp_mul_comba8(fp_int *A, fp_int *B, fp_int *C)
26 {
27    fp_digit c0, c1, c2;
28 #ifndef WOLFSSL_SMALL_STACK
29    fp_digit at[16];
30 #else
31    fp_digit *at;
32 #endif
33 
34 #ifdef WOLFSSL_SMALL_STACK
35    at = (fp_digit*)XMALLOC(sizeof(fp_digit) * 16, NULL, DYNAMIC_TYPE_TMP_BUFFER);
36    if (at == NULL)
37        return FP_MEM;
38 #endif
39 
40    XMEMCPY(at, A->dp, 8 * sizeof(fp_digit));
41    XMEMCPY(at+8, B->dp, 8 * sizeof(fp_digit));
42    COMBA_START;
43 
44    COMBA_CLEAR;
45    /* 0 */
46    MULADD(at[0], at[8]);
47    COMBA_STORE(C->dp[0]);
48    /* 1 */
49    COMBA_FORWARD;
50    MULADD(at[0], at[9]);    MULADD(at[1], at[8]);
51    COMBA_STORE(C->dp[1]);
52    /* 2 */
53    COMBA_FORWARD;
54    MULADD(at[0], at[10]);    MULADD(at[1], at[9]);    MULADD(at[2], at[8]);
55    COMBA_STORE(C->dp[2]);
56    /* 3 */
57    COMBA_FORWARD;
58    MULADD(at[0], at[11]);    MULADD(at[1], at[10]);    MULADD(at[2], at[9]);    MULADD(at[3], at[8]);
59    COMBA_STORE(C->dp[3]);
60    /* 4 */
61    COMBA_FORWARD;
62    MULADD(at[0], at[12]);    MULADD(at[1], at[11]);    MULADD(at[2], at[10]);    MULADD(at[3], at[9]);    MULADD(at[4], at[8]);
63    COMBA_STORE(C->dp[4]);
64    /* 5 */
65    COMBA_FORWARD;
66    MULADD(at[0], at[13]);    MULADD(at[1], at[12]);    MULADD(at[2], at[11]);    MULADD(at[3], at[10]);    MULADD(at[4], at[9]);    MULADD(at[5], at[8]);
67    COMBA_STORE(C->dp[5]);
68    /* 6 */
69    COMBA_FORWARD;
70    MULADD(at[0], at[14]);    MULADD(at[1], at[13]);    MULADD(at[2], at[12]);    MULADD(at[3], at[11]);    MULADD(at[4], at[10]);    MULADD(at[5], at[9]);    MULADD(at[6], at[8]);
71    COMBA_STORE(C->dp[6]);
72    /* 7 */
73    COMBA_FORWARD;
74    MULADD(at[0], at[15]);    MULADD(at[1], at[14]);    MULADD(at[2], at[13]);    MULADD(at[3], at[12]);    MULADD(at[4], at[11]);    MULADD(at[5], at[10]);    MULADD(at[6], at[9]);    MULADD(at[7], at[8]);
75    COMBA_STORE(C->dp[7]);
76    /* 8 */
77    COMBA_FORWARD;
78    MULADD(at[1], at[15]);    MULADD(at[2], at[14]);    MULADD(at[3], at[13]);    MULADD(at[4], at[12]);    MULADD(at[5], at[11]);    MULADD(at[6], at[10]);    MULADD(at[7], at[9]);
79    COMBA_STORE(C->dp[8]);
80    /* 9 */
81    COMBA_FORWARD;
82    MULADD(at[2], at[15]);    MULADD(at[3], at[14]);    MULADD(at[4], at[13]);    MULADD(at[5], at[12]);    MULADD(at[6], at[11]);    MULADD(at[7], at[10]);
83    COMBA_STORE(C->dp[9]);
84    /* 10 */
85    COMBA_FORWARD;
86    MULADD(at[3], at[15]);    MULADD(at[4], at[14]);    MULADD(at[5], at[13]);    MULADD(at[6], at[12]);    MULADD(at[7], at[11]);
87    COMBA_STORE(C->dp[10]);
88    /* 11 */
89    COMBA_FORWARD;
90    MULADD(at[4], at[15]);    MULADD(at[5], at[14]);    MULADD(at[6], at[13]);    MULADD(at[7], at[12]);
91    COMBA_STORE(C->dp[11]);
92    /* 12 */
93    COMBA_FORWARD;
94    MULADD(at[5], at[15]);    MULADD(at[6], at[14]);    MULADD(at[7], at[13]);
95    COMBA_STORE(C->dp[12]);
96    /* 13 */
97    COMBA_FORWARD;
98    MULADD(at[6], at[15]);    MULADD(at[7], at[14]);
99    COMBA_STORE(C->dp[13]);
100    /* 14 */
101    COMBA_FORWARD;
102    MULADD(at[7], at[15]);
103    COMBA_STORE(C->dp[14]);
104    COMBA_STORE2(C->dp[15]);
105    C->used = 16;
106    C->sign = A->sign ^ B->sign;
107    fp_clamp(C);
108    COMBA_FINI;
109 
110 #ifdef WOLFSSL_SMALL_STACK
111    XFREE(at, NULL, DYNAMIC_TYPE_TMP_BUFFER);
112 #endif
113    return FP_OKAY;
114 }
115 #endif
116