1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** NetX Crypto Component */
17 /** */
18 /** Huge Number */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23 #define NX_CRYPTO_SOURCE_CODE
24
25
26 /* Include necessary system files. */
27 #include "stdio.h"
28 #include "nx_crypto_huge_number.h"
29
30 #ifndef NX_CRYPTO_SELF_TEST
31 /**************************************************************************/
32 /* */
33 /* FUNCTION RELEASE */
34 /* */
35 /* _nx_crypto_huge_number_add_digit PORTABLE C */
36 /* 6.1.7 */
37 /* AUTHOR */
38 /* */
39 /* Timothy Stapko, Microsoft Corporation */
40 /* */
41 /* DESCRIPTION */
42 /* */
43 /* This function calculates addition for huge number and digit. */
44 /* */
45 /* Note: Result is stored in value. */
46 /* */
47 /* INPUT */
48 /* */
49 /* value Huge number number */
50 /* digit Digit value */
51 /* */
52 /* OUTPUT */
53 /* */
54 /* None */
55 /* */
56 /* CALLS */
57 /* */
58 /* _nx_crypto_huge_number_add_digit_unsigned */
59 /* Calculate addition for */
60 /* unsigned huge numbers */
61 /* _nx_crypto_huge_number_subtract_digit_unsigned */
62 /* Calculate subtraction for */
63 /* unsigned huge numbers */
64 /* */
65 /* CALLED BY */
66 /* */
67 /* Application Code */
68 /* */
69 /* RELEASE HISTORY */
70 /* */
71 /* DATE NAME DESCRIPTION */
72 /* */
73 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */
74 /* 09-30-2020 Timothy Stapko Modified comment(s), */
75 /* resulting in version 6.1 */
76 /* 06-02-2021 Bhupendra Naphade Modified comment(s), */
77 /* renamed FIPS symbol to */
78 /* self-test, */
79 /* resulting in version 6.1.7 */
80 /* */
81 /**************************************************************************/
_nx_crypto_huge_number_add_digit(NX_CRYPTO_HUGE_NUMBER * value,HN_UBASE digit)82 NX_CRYPTO_KEEP VOID _nx_crypto_huge_number_add_digit(NX_CRYPTO_HUGE_NUMBER *value, HN_UBASE digit)
83 {
84 if (value -> nx_crypto_huge_number_is_negative)
85 {
86 if ((value -> nx_crypto_huge_number_size > 1) ||
87 (value -> nx_crypto_huge_number_data[0] >= digit))
88 {
89
90 /* |value| >= digit */
91 /* value = -(|value| - digit) */
92 _nx_crypto_huge_number_subtract_digit_unsigned(value, digit);
93 }
94 else
95 {
96
97 /* value < digit */
98 /* value = digit - |value| */
99 value -> nx_crypto_huge_number_data[0] = digit - value -> nx_crypto_huge_number_data[0];
100 value -> nx_crypto_huge_number_is_negative = NX_CRYPTO_FALSE;
101 }
102 }
103 else
104 {
105
106 /* value = value + digit */
107 _nx_crypto_huge_number_add_digit_unsigned(value, digit);
108 }
109 }
110
111 /**************************************************************************/
112 /* */
113 /* FUNCTION RELEASE */
114 /* */
115 /* _nx_crypto_huge_number_subtract_digit PORTABLE C */
116 /* 6.1 */
117 /* AUTHOR */
118 /* */
119 /* Timothy Stapko, Microsoft Corporation */
120 /* */
121 /* DESCRIPTION */
122 /* */
123 /* This function calculates subtraction for huge number and digit. */
124 /* */
125 /* Note: Result is stored in value. */
126 /* */
127 /* INPUT */
128 /* */
129 /* value Huge number number */
130 /* digit Digit value */
131 /* */
132 /* OUTPUT */
133 /* */
134 /* None */
135 /* */
136 /* CALLS */
137 /* */
138 /* _nx_crypto_huge_number_add_digit_unsigned */
139 /* Calculate addition for */
140 /* unsigned huge numbers */
141 /* _nx_crypto_huge_number_subtract_digit_unsigned */
142 /* Calculate subtraction for */
143 /* unsigned huge numbers */
144 /* */
145 /* CALLED BY */
146 /* */
147 /* Application Code */
148 /* */
149 /* RELEASE HISTORY */
150 /* */
151 /* DATE NAME DESCRIPTION */
152 /* */
153 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */
154 /* 09-30-2020 Timothy Stapko Modified comment(s), */
155 /* resulting in version 6.1 */
156 /* */
157 /**************************************************************************/
_nx_crypto_huge_number_subtract_digit(NX_CRYPTO_HUGE_NUMBER * value,HN_UBASE digit)158 NX_CRYPTO_KEEP VOID _nx_crypto_huge_number_subtract_digit(NX_CRYPTO_HUGE_NUMBER *value, HN_UBASE digit)
159 {
160 if (value -> nx_crypto_huge_number_is_negative)
161 {
162
163 /* value = -(|value| + digit) */
164 _nx_crypto_huge_number_add_digit_unsigned(value, digit);
165 }
166 else
167 {
168 if ((value -> nx_crypto_huge_number_size > 1) ||
169 (value -> nx_crypto_huge_number_data[0] >= digit))
170 {
171
172 /* value >= digit */
173 /* value = value - digit */
174 _nx_crypto_huge_number_subtract_digit_unsigned(value, digit);
175 }
176 else
177 {
178
179 /* value < digit */
180 /* value = -(digit - value) */
181 value -> nx_crypto_huge_number_data[0] = digit - value -> nx_crypto_huge_number_data[0];
182 value -> nx_crypto_huge_number_is_negative = NX_CRYPTO_TRUE;
183 }
184 }
185 }
186
187 /**************************************************************************/
188 /* */
189 /* FUNCTION RELEASE */
190 /* */
191 /* _nx_crypto_huge_number_power_modulus PORTABLE C */
192 /* 6.1.9 */
193 /* AUTHOR */
194 /* */
195 /* Timothy Stapko, Microsoft Corporation */
196 /* */
197 /* DESCRIPTION */
198 /* */
199 /* This function raises a huge number to the power of a second huge */
200 /* number using a third huge number as a modulus. The result is placed */
201 /* in a fourth huge number. */
202 /* */
203 /* NOTE: This function makes use of the Huge Number scratch buffers. */
204 /* Each operand and the result must have the */
205 /* nx_crypto_huge_number_scratch member set to point to a buffer */
206 /* of size equal to the number data buffer and that size stored */
207 /* in the nx_crypto_huge_buffer_size member. */
208 /* */
209 /* INPUT */
210 /* */
211 /* number Number being exponentiated */
212 /* exponent Exponent number */
213 /* modulus Modulus number */
214 /* result Result buffer */
215 /* */
216 /* OUTPUT */
217 /* */
218 /* None */
219 /* */
220 /* CALLS */
221 /* */
222 /* NX_CRYPTO_HUGE_NUMBER_COPY Copy huge number */
223 /* NX_CRYPTO_HUGE_NUMBER_INITIALIZE Initialize the buffer of */
224 /* huge number */
225 /* NX_CRYPTO_HUGE_NUMBER_SET_DIGIT Set value of huge number */
226 /* between 0 and (HN_RADIX - 1)*/
227 /* _nx_crypto_huge_number_multiply Multiply a huge number by */
228 /* a second huge number */
229 /* _nx_crypto_huge_number_modulus Calculate the remainder after */
230 /* dividing a huge number by */
231 /* another huge number */
232 /* _nx_crypto_huge_number_square Compute the square of a value */
233 /* */
234 /* CALLED BY */
235 /* */
236 /* Application Code */
237 /* */
238 /* RELEASE HISTORY */
239 /* */
240 /* DATE NAME DESCRIPTION */
241 /* */
242 /* 05-19-2020 Timothy Stapko Initial Version 6.0 */
243 /* 09-30-2020 Timothy Stapko Modified comment(s), */
244 /* resulting in version 6.1 */
245 /* 10-15-2021 Bhupendra Naphade Modified comment(s), */
246 /* resulting in version 6.1.9 */
247 /* */
248 /**************************************************************************/
_nx_crypto_huge_number_power_modulus(NX_CRYPTO_HUGE_NUMBER * number,NX_CRYPTO_HUGE_NUMBER * exponent,NX_CRYPTO_HUGE_NUMBER * modulus,NX_CRYPTO_HUGE_NUMBER * result,HN_UBASE * scratch)249 NX_CRYPTO_KEEP VOID _nx_crypto_huge_number_power_modulus(NX_CRYPTO_HUGE_NUMBER *number,
250 NX_CRYPTO_HUGE_NUMBER *exponent,
251 NX_CRYPTO_HUGE_NUMBER *modulus,
252 NX_CRYPTO_HUGE_NUMBER *result,
253 HN_UBASE *scratch)
254 {
255 UINT index, bit;
256 HN_UBASE cur_block;
257 HN_UBASE *val;
258 UINT exp_size;
259 NX_CRYPTO_HUGE_NUMBER temp;
260
261 NX_CRYPTO_HUGE_NUMBER_INITIALIZE(&temp, scratch,
262 number -> nx_crypto_huge_buffer_size);
263
264 /* Clear out the result since we need it to start with a simple value. */
265 NX_CRYPTO_HUGE_NUMBER_SET_DIGIT(result, 1);
266
267 exp_size = exponent -> nx_crypto_huge_number_size;
268 val = exponent -> nx_crypto_huge_number_data;
269 /* Loop through the bits of the exponent. For each bit set, multiply the result by the running square. */
270 for (index = 0; index < exp_size; index++)
271 {
272 /* Current byte in the exponent determines whether we multiply or not. */
273 cur_block = val[index];
274
275 /* Loop over the bits in the current byte to see whether we add or not. */
276 for (bit = 0; bit < HN_SHIFT; ++bit)
277 {
278 /* A non-zero bit means we need to multiply. */
279 if (cur_block & 1)
280 {
281 /* Multiply the result by the running square (number) and put the result in a scratch buffer. */
282 _nx_crypto_huge_number_multiply(result, number, &temp);
283 NX_CRYPTO_HUGE_NUMBER_COPY(result, &temp);
284
285 /* Take the modulus of the product we just calculated. If we didn't do this here the result would quickly grow
286 larger than our buffers (or the universe) could store. Put the result in our result buffer. */
287 _nx_crypto_huge_number_modulus(result, modulus);
288 }
289
290 /* Shift the data to go to the next bit. */
291 cur_block = cur_block >> 1;
292
293 _nx_crypto_huge_number_square(number, &temp);
294 _nx_crypto_huge_number_modulus(&temp, modulus);
295 NX_CRYPTO_HUGE_NUMBER_COPY(number, &temp);
296
297 /* Take the modulus of our squared product and put the result into our number buffer. */
298 }
299 }
300 }
301
302 #endif
303
