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 "cryptlib.h"
62 #include <openssl/buffer.h>
63 #include "bn_lcl.h"
64
65 static const char Hex[]="0123456789ABCDEF";
66
67 /* Must 'OPENSSL_free' the returned data */
68 char *BN_bn2hex(const BIGNUM *a)
69 {
70 int i,j,v,z=0;
71 char *buf;
72 char *p;
73
74 buf=(char *)OPENSSL_malloc(a->top*BN_BYTES*2+2);
75 if (buf == NULL)
76 {
77 BNerr(BN_F_BN_BN2HEX,ERR_R_MALLOC_FAILURE);
78 goto err;
79 }
80 p=buf;
81 if (a->neg) *(p++)='-';
82 if (BN_is_zero(a)) *(p++)='0';
83 for (i=a->top-1; i >=0; i--)
84 {
85 for (j=BN_BITS2-8; j >= 0; j-=8)
86 {
87 /* strip leading zeros */
88 v=((int)(a->d[i]>>(long)j))&0xff;
89 if (z || (v != 0))
90 {
91 *(p++)=Hex[v>>4];
92 *(p++)=Hex[v&0x0f];
93 z=1;
94 }
95 }
96 }
97 *p='\0';
98 err:
99 return(buf);
100 }
101
102 /* Must 'OPENSSL_free' the returned data */
103 char *BN_bn2dec(const BIGNUM *a)
104 {
105 int i=0,num, ok = 0;
106 char *buf=NULL;
107 char *p;
108 BIGNUM *t=NULL;
109 BN_ULONG *bn_data=NULL,*lp;
110
111 /* get an upper bound for the length of the decimal integer
112 * num <= (BN_num_bits(a) + 1) * log(2)
113 * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error)
114 * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1
115 */
116 i=BN_num_bits(a)*3;
117 num=(i/10+i/1000+1)+1;
118 bn_data=(BN_ULONG *)OPENSSL_malloc((num/BN_DEC_NUM+1)*sizeof(BN_ULONG));
119 buf=(char *)OPENSSL_malloc(num+3);
120 if ((buf == NULL) || (bn_data == NULL))
121 {
122 BNerr(BN_F_BN_BN2DEC,ERR_R_MALLOC_FAILURE);
123 goto err;
124 }
125 if ((t=BN_dup(a)) == NULL) goto err;
126
127 #define BUF_REMAIN (num+3 - (size_t)(p - buf))
128 p=buf;
129 lp=bn_data;
130 if (BN_is_zero(t))
131 {
132 *(p++)='0';
133 *(p++)='\0';
134 }
135 else
136 {
137 if (BN_is_negative(t))
138 *p++ = '-';
139
140 i=0;
141 while (!BN_is_zero(t))
142 {
143 *lp=BN_div_word(t,BN_DEC_CONV);
144 lp++;
145 }
146 lp--;
147 /* We now have a series of blocks, BN_DEC_NUM chars
148 * in length, where the last one needs truncation.
149 * The blocks need to be reversed in order. */
150 BIO_snprintf(p,BUF_REMAIN,BN_DEC_FMT1,*lp);
151 while (*p) p++;
152 while (lp != bn_data)
153 {
154 lp--;
155 BIO_snprintf(p,BUF_REMAIN,BN_DEC_FMT2,*lp);
156 while (*p) p++;
157 }
158 }
159 ok = 1;
160 err:
161 if (bn_data != NULL) OPENSSL_free(bn_data);
162 if (t != NULL) BN_free(t);
163 if (!ok && buf)
164 {
165 OPENSSL_free(buf);
166 buf = NULL;
167 }
168
169 return(buf);
170 }
171
172 int BN_hex2bn(BIGNUM **bn, const char *a)
173 {
174 BIGNUM *ret=NULL;
175 BN_ULONG l=0;
176 int neg=0,h,m,i,j,k,c;
177 int num;
178
179 if ((a == NULL) || (*a == '\0')) return(0);
180
181 if (*a == '-') { neg=1; a++; }
182
183 for (i=0; isxdigit((unsigned char) a[i]); i++)
184 ;
185
186 num=i+neg;
187 if (bn == NULL) return(num);
188
189 /* a is the start of the hex digits, and it is 'i' long */
190 if (*bn == NULL)
191 {
192 if ((ret=BN_new()) == NULL) return(0);
193 }
194 else
195 {
196 ret= *bn;
197 BN_zero(ret);
198 }
199
200 /* i is the number of hex digests; */
201 if (bn_expand(ret,i*4) == NULL) goto err;
202
203 j=i; /* least significant 'hex' */
204 m=0;
205 h=0;
206 while (j > 0)
207 {
208 m=((BN_BYTES*2) <= j)?(BN_BYTES*2):j;
209 l=0;
210 for (;;)
211 {
212 c=a[j-m];
213 if ((c >= '0') && (c <= '9')) k=c-'0';
214 else if ((c >= 'a') && (c <= 'f')) k=c-'a'+10;
215 else if ((c >= 'A') && (c <= 'F')) k=c-'A'+10;
216 else k=0; /* paranoia */
217 l=(l<<4)|k;
218
219 if (--m <= 0)
220 {
221 ret->d[h++]=l;
222 break;
223 }
224 }
225 j-=(BN_BYTES*2);
226 }
227 ret->top=h;
228 bn_correct_top(ret);
229 ret->neg=neg;
230
231 *bn=ret;
232 bn_check_top(ret);
233 return(num);
234 err:
235 if (*bn == NULL) BN_free(ret);
236 return(0);
237 }
238
239 int BN_dec2bn(BIGNUM **bn, const char *a)
240 {
241 BIGNUM *ret=NULL;
242 BN_ULONG l=0;
243 int neg=0,i,j;
244 int num;
245
246 if ((a == NULL) || (*a == '\0')) return(0);
247 if (*a == '-') { neg=1; a++; }
248
249 for (i=0; isdigit((unsigned char) a[i]); i++)
250 ;
251
252 num=i+neg;
253 if (bn == NULL) return(num);
254
255 /* a is the start of the digits, and it is 'i' long.
256 * We chop it into BN_DEC_NUM digits at a time */
257 if (*bn == NULL)
258 {
259 if ((ret=BN_new()) == NULL) return(0);
260 }
261 else
262 {
263 ret= *bn;
264 BN_zero(ret);
265 }
266
267 /* i is the number of digests, a bit of an over expand; */
268 if (bn_expand(ret,i*4) == NULL) goto err;
269
270 j=BN_DEC_NUM-(i%BN_DEC_NUM);
271 if (j == BN_DEC_NUM) j=0;
272 l=0;
273 while (*a)
274 {
275 l*=10;
276 l+= *a-'0';
277 a++;
278 if (++j == BN_DEC_NUM)
279 {
280 BN_mul_word(ret,BN_DEC_CONV);
281 BN_add_word(ret,l);
282 l=0;
283 j=0;
284 }
285 }
286 ret->neg=neg;
287
288 bn_correct_top(ret);
289 *bn=ret;
290 bn_check_top(ret);
291 return(num);
292 err:
293 if (*bn == NULL) BN_free(ret);
294 return(0);
295 }
296
297 int BN_asc2bn(BIGNUM **bn, const char *a)
298 {
299 const char *p = a;
300 if (*p == '-')
301 p++;
302
303 if (p[0] == '0' && (p[1] == 'X' || p[1] == 'x'))
304 {
305 if (!BN_hex2bn(bn, p + 2))
306 return 0;
307 }
308 else
309 {
310 if (!BN_dec2bn(bn, p))
311 return 0;
312 }
313 if (*a == '-')
314 (*bn)->neg = 1;
315 return 1;
316 }
317
318 #ifndef OPENSSL_NO_BIO
319 #ifndef OPENSSL_NO_FP_API
320 int BN_print_fp(FILE *fp, const BIGNUM *a)
321 {
322 BIO *b;
323 int ret;
324
325 if ((b=BIO_new(BIO_s_file())) == NULL)
326 return(0);
327 BIO_set_fp(b,fp,BIO_NOCLOSE);
328 ret=BN_print(b,a);
329 BIO_free(b);
330 return(ret);
331 }
332 #endif
333
334 int BN_print(BIO *bp, const BIGNUM *a)
335 {
336 int i,j,v,z=0;
337 int ret=0;
338
339 if ((a->neg) && (BIO_write(bp,"-",1) != 1)) goto end;
340 if (BN_is_zero(a) && (BIO_write(bp,"0",1) != 1)) goto end;
341 for (i=a->top-1; i >=0; i--)
342 {
343 for (j=BN_BITS2-4; j >= 0; j-=4)
344 {
345 /* strip leading zeros */
346 v=((int)(a->d[i]>>(long)j))&0x0f;
347 if (z || (v != 0))
348 {
349 if (BIO_write(bp,&(Hex[v]),1) != 1)
350 goto end;
351 z=1;
352 }
353 }
354 }
355 ret=1;
356 end:
357 return(ret);
358 }
359 #endif
360
361 char *BN_options(void)
362 {
363 static int init=0;
364 static char data[16];
365
366 if (!init)
367 {
368 init++;
369 #ifdef BN_LLONG
370 BIO_snprintf(data,sizeof data,"bn(%d,%d)",
371 (int)sizeof(BN_ULLONG)*8,(int)sizeof(BN_ULONG)*8);
372 #else
373 BIO_snprintf(data,sizeof data,"bn(%d,%d)",
374 (int)sizeof(BN_ULONG)*8,(int)sizeof(BN_ULONG)*8);
375 #endif
376 }
377 return(data);
378 }