1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
|
/*
* Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include <stdio.h>
#include <ctype.h>
#include <limits.h>
#include "internal/cryptlib.h"
#include <openssl/buffer.h>
#include "bn_lcl.h"
static const char Hex[] = "0123456789ABCDEF";
/* Must 'OPENSSL_free' the returned data */
char *BN_bn2hex(const BIGNUM *a)
{
int i, j, v, z = 0;
char *buf;
char *p;
if (BN_is_zero(a))
return OPENSSL_strdup("0");
buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2);
if (buf == NULL) {
BNerr(BN_F_BN_BN2HEX, ERR_R_MALLOC_FAILURE);
goto err;
}
p = buf;
if (a->neg)
*(p++) = '-';
for (i = a->top - 1; i >= 0; i--) {
for (j = BN_BITS2 - 8; j >= 0; j -= 8) {
/* strip leading zeros */
v = ((int)(a->d[i] >> (long)j)) & 0xff;
if (z || (v != 0)) {
*(p++) = Hex[v >> 4];
*(p++) = Hex[v & 0x0f];
z = 1;
}
}
}
*p = '\0';
err:
return buf;
}
/* Must 'OPENSSL_free' the returned data */
char *BN_bn2dec(const BIGNUM *a)
{
int i = 0, num, ok = 0, n, tbytes;
char *buf = NULL;
char *p;
BIGNUM *t = NULL;
BN_ULONG *bn_data = NULL, *lp;
int bn_data_num;
/*-
* get an upper bound for the length of the decimal integer
* num <= (BN_num_bits(a) + 1) * log(2)
* <= 3 * BN_num_bits(a) * 0.101 + log(2) + 1 (rounding error)
* <= 3 * BN_num_bits(a) / 10 + 3 * BN_num_bits / 1000 + 1 + 1
*/
i = BN_num_bits(a) * 3;
num = (i / 10 + i / 1000 + 1) + 1;
tbytes = num + 3; /* negative and terminator and one spare? */
bn_data_num = num / BN_DEC_NUM + 1;
bn_data = OPENSSL_malloc(bn_data_num * sizeof(BN_ULONG));
buf = OPENSSL_malloc(tbytes);
if ((buf == NULL) || (bn_data == NULL)) {
BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE);
goto err;
}
if ((t = BN_dup(a)) == NULL)
goto err;
p = buf;
lp = bn_data;
if (BN_is_zero(t)) {
*(p++) = '0';
*(p++) = '\0';
} else {
if (BN_is_negative(t))
*p++ = '-';
while (!BN_is_zero(t)) {
if (lp - bn_data >= bn_data_num)
goto err;
*lp = BN_div_word(t, BN_DEC_CONV);
if (*lp == (BN_ULONG)-1)
goto err;
lp++;
}
lp--;
/*
* We now have a series of blocks, BN_DEC_NUM chars in length, where
* the last one needs truncation. The blocks need to be reversed in
* order.
*/
n = BIO_snprintf(p, tbytes - (size_t)(p - buf), BN_DEC_FMT1, *lp);
if (n < 0)
goto err;
p += n;
while (lp != bn_data) {
lp--;
n = BIO_snprintf(p, tbytes - (size_t)(p - buf), BN_DEC_FMT2, *lp);
if (n < 0)
goto err;
p += n;
}
}
ok = 1;
err:
OPENSSL_free(bn_data);
BN_free(t);
if (ok)
return buf;
OPENSSL_free(buf);
return NULL;
}
int BN_hex2bn(BIGNUM **bn, const char *a)
{
BIGNUM *ret = NULL;
BN_ULONG l = 0;
int neg = 0, h, m, i, j, k, c;
int num;
if ((a == NULL) || (*a == '\0'))
return 0;
if (*a == '-') {
neg = 1;
a++;
}
for (i = 0; i <= (INT_MAX/4) && isxdigit((unsigned char)a[i]); i++)
continue;
if (i == 0 || i > INT_MAX/4)
goto err;
num = i + neg;
if (bn == NULL)
return num;
/* a is the start of the hex digits, and it is 'i' long */
if (*bn == NULL) {
if ((ret = BN_new()) == NULL)
return 0;
} else {
ret = *bn;
BN_zero(ret);
}
/* i is the number of hex digits */
if (bn_expand(ret, i * 4) == NULL)
goto err;
j = i; /* least significant 'hex' */
m = 0;
h = 0;
while (j > 0) {
m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j;
l = 0;
for (;;) {
c = a[j - m];
k = OPENSSL_hexchar2int(c);
if (k < 0)
k = 0; /* paranoia */
l = (l << 4) | k;
if (--m <= 0) {
ret->d[h++] = l;
break;
}
}
j -= (BN_BYTES * 2);
}
ret->top = h;
bn_correct_top(ret);
*bn = ret;
bn_check_top(ret);
/* Don't set the negative flag if it's zero. */
if (ret->top != 0)
ret->neg = neg;
return num;
err:
if (*bn == NULL)
BN_free(ret);
return 0;
}
int BN_dec2bn(BIGNUM **bn, const char *a)
{
BIGNUM *ret = NULL;
BN_ULONG l = 0;
int neg = 0, i, j;
int num;
if ((a == NULL) || (*a == '\0'))
return 0;
if (*a == '-') {
neg = 1;
a++;
}
for (i = 0; i <= (INT_MAX/4) && isdigit((unsigned char)a[i]); i++)
continue;
if (i == 0 || i > INT_MAX/4)
goto err;
num
|