1 /* crypto/bn/bn_print.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <stdio.h>
60 #include <ctype.h>
61 #include <limits.h>
62 #include "cryptlib.h"
63 #include <openssl/buffer.h>
64 #include "bn_lcl.h"
65
66 static const char Hex[] = "0123456789ABCDEF";
67
68 /* Must 'OPENSSL_free' the returned data */
BN_bn2hex(const BIGNUM * a)69 char *BN_bn2hex(const BIGNUM *a)
70 {
71 int i, j, v, z = 0;
72 char *buf;
73 char *p;
74
75 if (BN_is_zero(a))
76 return OPENSSL_strdup("0");
77 buf = OPENSSL_malloc(a->top * BN_BYTES * 2 + 2);
78 if (buf == NULL) {
79 BNerr(BN_F_BN_BN2HEX, ERR_R_MALLOC_FAILURE);
80 goto err;
81 }
82 p = buf;
83 if (a->neg)
84 *(p++) = '-';
85 for (i = a->top - 1; i >= 0; i--) {
86 for (j = BN_BITS2 - 8; j >= 0; j -= 8) {
87 /* strip leading zeros */
88 v = ((int)(a->d[i] >> (long)j)) & 0xff;
89 if (z || (v != 0)) {
90 *(p++) = Hex[v >> 4];
91 *(p++) = Hex[v & 0x0f];
92 z = 1;
93 }
94 }
95 }
96 *p = '\0';
97 err:
98 return (buf);
99 }
100
101 /* Must 'OPENSSL_free' the returned data */
BN_bn2dec(const BIGNUM * a)102 char *BN_bn2dec(const BIGNUM *a)
103 {
104 int i = 0, num, ok = 0;
105 char *buf = NULL;
106 char *p;
107 BIGNUM *t = NULL;
108 BN_ULONG *bn_data = NULL, *lp;
109 int bn_data_num;
110
111 /*-
112 * get an upper bound for the length of the decimal integer
113 * num <= (BN_num_bits(a) + 1) * log(2)
114 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error)
115 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1
116 */
117 i = BN_num_bits(a) * 3;
118 num = (i / 10 + i / 1000 + 1) + 1;
119 bn_data_num = num / BN_DEC_NUM + 1;
120 bn_data = OPENSSL_malloc(bn_data_num * sizeof(BN_ULONG));
121 buf = OPENSSL_malloc(num + 3);
122 if ((buf == NULL) || (bn_data == NULL)) {
123 BNerr(BN_F_BN_BN2DEC, ERR_R_MALLOC_FAILURE);
124 goto err;
125 }
126 if ((t = BN_dup(a)) == NULL)
127 goto err;
128
129 #define BUF_REMAIN (num+3 - (size_t)(p - buf))
130 p = buf;
131 lp = bn_data;
132 if (BN_is_zero(t)) {
133 *(p++) = '0';
134 *(p++) = '\0';
135 } else {
136 if (BN_is_negative(t))
137 *p++ = '-';
138
139 while (!BN_is_zero(t)) {
140 if (lp - bn_data >= bn_data_num)
141 goto err;
142 *lp = BN_div_word(t, BN_DEC_CONV);
143 if (*lp == (BN_ULONG)-1)
144 goto err;
145 lp++;
146 }
147 lp--;
148 /*
149 * We now have a series of blocks, BN_DEC_NUM chars in length, where
150 * the last one needs truncation. The blocks need to be reversed in
151 * order.
152 */
153 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp);
154 while (*p)
155 p++;
156 while (lp != bn_data) {
157 lp--;
158 BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp);
159 while (*p)
160 p++;
161 }
162 }
163 ok = 1;
164 err:
165 if (bn_data != NULL)
166 OPENSSL_free(bn_data);
167 if (t != NULL)
168 BN_free(t);
169 if (!ok && buf) {
170 OPENSSL_free(buf);
171 buf = NULL;
172 }
173
174 return (buf);
175 }
176
BN_hex2bn(BIGNUM ** bn,const char * a)177 int BN_hex2bn(BIGNUM **bn, const char *a)
178 {
179 BIGNUM *ret = NULL;
180 BN_ULONG l = 0;
181 int neg = 0, h, m, i, j, k, c;
182 int num;
183
184 if ((a == NULL) || (*a == '\0'))
185 return (0);
186
187 if (*a == '-') {
188 neg = 1;
189 a++;
190 }
191
192 for (i = 0; i <= (INT_MAX/4) && isxdigit((unsigned char)a[i]); i++)
193 continue;
194
195 if (i > INT_MAX/4)
196 goto err;
197
198 num = i + neg;
199 if (bn == NULL)
200 return (num);
201
202 /* a is the start of the hex digits, and it is 'i' long */
203 if (*bn == NULL) {
204 if ((ret = BN_new()) == NULL)
205 return (0);
206 } else {
207 ret = *bn;
208 BN_zero(ret);
209 }
210
211 /* i is the number of hex digits */
212 if (bn_expand(ret, i * 4) == NULL)
213 goto err;
214
215 j = i; /* least significant 'hex' */
216 m = 0;
217 h = 0;
218 while (j > 0) {
219 m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j;
220 l = 0;
221 for (;;) {
222 c = a[j - m];
223 if ((c >= '0') && (c <= '9'))
224 k = c - '0';
225 else if ((c >= 'a') && (c <= 'f'))
226 k = c - 'a' + 10;
227 else if ((c >= 'A') && (c <= 'F'))
228 k = c - 'A' + 10;
229 else
230 k = 0; /* paranoia */
231 l = (l << 4) | k;
232
233 if (--m <= 0) {
234 ret->d[h++] = l;
235 break;
236 }
237 }
238 j -= (BN_BYTES * 2);
239 }
240 ret->top = h;
241 bn_correct_top(ret);
242
243 *bn = ret;
244 bn_check_top(ret);
245 /* Don't set the negative flag if it's zero. */
246 if (ret->top != 0)
247 ret->neg = neg;
248 return (num);
249 err:
250 if (*bn == NULL)
251 BN_free(ret);
252 return (0);
253 }
254
BN_dec2bn(BIGNUM ** bn,const char * a)255 int BN_dec2bn(BIGNUM **bn, const char *a)
256 {
257 BIGNUM *ret = NULL;
258 BN_ULONG l = 0;
259 int neg = 0, i, j;
260 int num;
261
262 if ((a == NULL) || (*a == '\0'))
263 return (0);
264 if (*a == '-') {
265 neg = 1;
266 a++;
267 }
268
269 for (i = 0; i <= (INT_MAX/4) && isdigit((unsigned char)a[i]); i++)
270 continue;
271
272 if (i > INT_MAX/4)
273 goto err;
274
275 num = i + neg;
276 if (bn == NULL)
277 return (num);
278
279 /*
280 * a is the start of the digits, and it is 'i' long. We chop it into
281 * BN_DEC_NUM digits at a time
282 */
283 if (*bn == NULL) {
284 if ((ret = BN_new()) == NULL)
285 return (0);
286 } else {
287 ret = *bn;
288 BN_zero(ret);
289 }
290
291 /* i is the number of digits, a bit of an over expand */
292 if (bn_expand(ret, i * 4) == NULL)
293 goto err;
294
295 j = BN_DEC_NUM - (i % BN_DEC_NUM);
296 if (j == BN_DEC_NUM)
297 j = 0;
298 l = 0;
299 while (--i >= 0) {
300 l *= 10;
301 l += *a - '0';
302 a++;
303 if (++j == BN_DEC_NUM) {
304 BN_mul_word(ret, BN_DEC_CONV);
305 BN_add_word(ret, l);
306 l = 0;
307 j = 0;
308 }
309 }
310
311 bn_correct_top(ret);
312 *bn = ret;
313 bn_check_top(ret);
314 /* Don't set the negative flag if it's zero. */
315 if (ret->top != 0)
316 ret->neg = neg;
317 return (num);
318 err:
319 if (*bn == NULL)
320 BN_free(ret);
321 return (0);
322 }
323
BN_asc2bn(BIGNUM ** bn,const char * a)324 int BN_asc2bn(BIGNUM **bn, const char *a)
325 {
326 const char *p = a;
327
328 if (*p == '-')
329 p++;
330
331 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x')) {
332 if (!BN_hex2bn(bn, p + 2))
333 return 0;
334 } else {
335 if (!BN_dec2bn(bn, p))
336 return 0;
337 }
338 /* Don't set the negative flag if it's zero. */
339 if (*a == '-' && (*bn)->top != 0)
340 (*bn)->neg = 1;
341 return 1;
342 }
343
344 #ifndef OPENSSL_NO_BIO
345 # ifndef OPENSSL_NO_FP_API
BN_print_fp(FILE * fp,const BIGNUM * a)346 int BN_print_fp(FILE *fp, const BIGNUM *a)
347 {
348 BIO *b;
349 int ret;
350
351 if ((b = BIO_new(BIO_s_file())) == NULL)
352 return (0);
353 BIO_set_fp(b, fp, BIO_NOCLOSE);
354 ret = BN_print(b, a);
355 BIO_free(b);
356 return (ret);
357 }
358 # endif
359
BN_print(BIO * bp,const BIGNUM * a)360 int BN_print(BIO *bp, const BIGNUM *a)
361 {
362 int i, j, v, z = 0;
363 int ret = 0;
364
365 if ((a->neg) && (BIO_write(bp, "-", 1) != 1))
366 goto end;
367 if (BN_is_zero(a) && (BIO_write(bp, "0", 1) != 1))
368 goto end;
369 for (i = a->top - 1; i >= 0; i--) {
370 for (j = BN_BITS2 - 4; j >= 0; j -= 4) {
371 /* strip leading zeros */
372 v = ((int)(a->d[i] >> (long)j)) & 0x0f;
373 if (z || (v != 0)) {
374 if (BIO_write(bp, &(Hex[v]), 1) != 1)
375 goto end;
376 z = 1;
377 }
378 }
379 }
380 ret = 1;
381 end:
382 return (ret);
383 }
384 #endif
385
BN_options(void)386 char *BN_options(void)
387 {
388 static int init = 0;
389 static char data[16];
390
391 if (!init) {
392 init++;
393 #ifdef BN_LLONG
394 BIO_snprintf(data, sizeof(data), "bn(%d,%d)",
395 (int)sizeof(BN_ULLONG) * 8, (int)sizeof(BN_ULONG) * 8);
396 #else
397 BIO_snprintf(data, sizeof(data), "bn(%d,%d)",
398 (int)sizeof(BN_ULONG) * 8, (int)sizeof(BN_ULONG) * 8);
399 #endif
400 }
401 return (data);
402 }
403