xref: /openbsd-src/lib/libcrypto/rsa/rsa_lib.c (revision 51060a0254e73346f8b3e0873a0894b39f7297f4)
1 /* crypto/rsa/rsa_lib.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 <openssl/crypto.h>
61 #include "cryptlib.h"
62 #include <openssl/lhash.h>
63 #include <openssl/bn.h>
64 #include <openssl/rsa.h>
65 #include <openssl/engine.h>
66 
67 const char *RSA_version="RSA" OPENSSL_VERSION_PTEXT;
68 
69 static const RSA_METHOD *default_RSA_meth=NULL;
70 
71 RSA *RSA_new(void)
72 	{
73 	return(RSA_new_method(NULL));
74 	}
75 
76 void RSA_set_default_method(const RSA_METHOD *meth)
77 	{
78 	default_RSA_meth = meth;
79 	}
80 
81 const RSA_METHOD *RSA_get_default_method(void)
82 	{
83 	if (default_RSA_meth == NULL)
84 		{
85 #ifdef RSA_NULL
86 		default_RSA_meth=RSA_null_method();
87 #else
88 #if 0 /* was: #ifdef RSAref */
89 		default_RSA_meth=RSA_PKCS1_RSAref();
90 #else
91 		default_RSA_meth=RSA_PKCS1_SSLeay();
92 #endif
93 #endif
94 		}
95 
96 	return default_RSA_meth;
97 	}
98 
99 const RSA_METHOD *RSA_get_method(const RSA *rsa)
100 	{
101 	return rsa->meth;
102 	}
103 
104 int RSA_set_method(RSA *rsa, const RSA_METHOD *meth)
105 	{
106 	/* NB: The caller is specifically setting a method, so it's not up to us
107 	 * to deal with which ENGINE it comes from. */
108 	const RSA_METHOD *mtmp;
109 	mtmp = rsa->meth;
110 	if (mtmp->finish) mtmp->finish(rsa);
111 	if (rsa->engine)
112 		{
113 		ENGINE_finish(rsa->engine);
114 		rsa->engine = NULL;
115 		}
116 	rsa->meth = meth;
117 	if (meth->init) meth->init(rsa);
118 	return 1;
119 	}
120 
121 RSA *RSA_new_method(ENGINE *engine)
122 	{
123 	RSA *ret;
124 
125 	ret=(RSA *)OPENSSL_malloc(sizeof(RSA));
126 	if (ret == NULL)
127 		{
128 		RSAerr(RSA_F_RSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
129 		return NULL;
130 		}
131 
132 	ret->meth = RSA_get_default_method();
133 	if (engine)
134 		{
135 		if (!ENGINE_init(engine))
136 			{
137 			RSAerr(RSA_F_RSA_NEW_METHOD, ERR_R_ENGINE_LIB);
138 			OPENSSL_free(ret);
139 			return NULL;
140 			}
141 		ret->engine = engine;
142 		}
143 	else
144 		ret->engine = ENGINE_get_default_RSA();
145 	if(ret->engine)
146 		{
147 		ret->meth = ENGINE_get_RSA(ret->engine);
148 		if(!ret->meth)
149 			{
150 			RSAerr(RSA_F_RSA_NEW_METHOD,
151 				ERR_R_ENGINE_LIB);
152 			ENGINE_finish(ret->engine);
153 			OPENSSL_free(ret);
154 			return NULL;
155 			}
156 		}
157 
158 	ret->pad=0;
159 	ret->version=0;
160 	ret->n=NULL;
161 	ret->e=NULL;
162 	ret->d=NULL;
163 	ret->p=NULL;
164 	ret->q=NULL;
165 	ret->dmp1=NULL;
166 	ret->dmq1=NULL;
167 	ret->iqmp=NULL;
168 	ret->references=1;
169 	ret->_method_mod_n=NULL;
170 	ret->_method_mod_p=NULL;
171 	ret->_method_mod_q=NULL;
172 	ret->blinding=NULL;
173 	ret->bignum_data=NULL;
174 	ret->flags=ret->meth->flags;
175 	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_RSA, ret, &ret->ex_data);
176 	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
177 		{
178 		if (ret->engine)
179 			ENGINE_finish(ret->engine);
180 		CRYPTO_free_ex_data(CRYPTO_EX_INDEX_RSA, ret, &ret->ex_data);
181 		OPENSSL_free(ret);
182 		ret=NULL;
183 		}
184 
185 	/* Enforce blinding. */
186 	ret->flags |= RSA_FLAG_BLINDING;
187 
188 	return(ret);
189 	}
190 
191 void RSA_free(RSA *r)
192 	{
193 	int i;
194 
195 	if (r == NULL) return;
196 
197 	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_RSA);
198 #ifdef REF_PRINT
199 	REF_PRINT("RSA",r);
200 #endif
201 	if (i > 0) return;
202 #ifdef REF_CHECK
203 	if (i < 0)
204 		{
205 		fprintf(stderr,"RSA_free, bad reference count\n");
206 		abort();
207 		}
208 #endif
209 
210 	if (r->meth->finish)
211 		r->meth->finish(r);
212 	if (r->engine)
213 		ENGINE_finish(r->engine);
214 
215 	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_RSA, r, &r->ex_data);
216 
217 	if (r->n != NULL) BN_clear_free(r->n);
218 	if (r->e != NULL) BN_clear_free(r->e);
219 	if (r->d != NULL) BN_clear_free(r->d);
220 	if (r->p != NULL) BN_clear_free(r->p);
221 	if (r->q != NULL) BN_clear_free(r->q);
222 	if (r->dmp1 != NULL) BN_clear_free(r->dmp1);
223 	if (r->dmq1 != NULL) BN_clear_free(r->dmq1);
224 	if (r->iqmp != NULL) BN_clear_free(r->iqmp);
225 	if (r->blinding != NULL) BN_BLINDING_free(r->blinding);
226 	if (r->bignum_data != NULL) OPENSSL_free_locked(r->bignum_data);
227 	OPENSSL_free(r);
228 	}
229 
230 int RSA_up_ref(RSA *r)
231 	{
232 	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_RSA);
233 #ifdef REF_PRINT
234 	REF_PRINT("RSA",r);
235 #endif
236 #ifdef REF_CHECK
237 	if (i < 2)
238 		{
239 		fprintf(stderr, "RSA_up_ref, bad reference count\n");
240 		abort();
241 		}
242 #endif
243 	return ((i > 1) ? 1 : 0);
244 	}
245 
246 int RSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
247 	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
248         {
249 	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_RSA, argl, argp,
250 				new_func, dup_func, free_func);
251         }
252 
253 int RSA_set_ex_data(RSA *r, int idx, void *arg)
254 	{
255 	return(CRYPTO_set_ex_data(&r->ex_data,idx,arg));
256 	}
257 
258 void *RSA_get_ex_data(const RSA *r, int idx)
259 	{
260 	return(CRYPTO_get_ex_data(&r->ex_data,idx));
261 	}
262 
263 int RSA_size(const RSA *r)
264 	{
265 	return(BN_num_bytes(r->n));
266 	}
267 
268 int RSA_public_encrypt(int flen, const unsigned char *from, unsigned char *to,
269 	     RSA *rsa, int padding)
270 	{
271 	return(rsa->meth->rsa_pub_enc(flen, from, to, rsa, padding));
272 	}
273 
274 int RSA_private_encrypt(int flen, const unsigned char *from, unsigned char *to,
275 	     RSA *rsa, int padding)
276 	{
277 	return(rsa->meth->rsa_priv_enc(flen, from, to, rsa, padding));
278 	}
279 
280 int RSA_private_decrypt(int flen, const unsigned char *from, unsigned char *to,
281 	     RSA *rsa, int padding)
282 	{
283 	return(rsa->meth->rsa_priv_dec(flen, from, to, rsa, padding));
284 	}
285 
286 int RSA_public_decrypt(int flen, const unsigned char *from, unsigned char *to,
287 	     RSA *rsa, int padding)
288 	{
289 	return(rsa->meth->rsa_pub_dec(flen, from, to, rsa, padding));
290 	}
291 
292 int RSA_flags(const RSA *r)
293 	{
294 	return((r == NULL)?0:r->meth->flags);
295 	}
296 
297 void RSA_blinding_off(RSA *rsa)
298 	{
299 	if (rsa->blinding != NULL)
300 		{
301 		BN_BLINDING_free(rsa->blinding);
302 		rsa->blinding=NULL;
303 		}
304 	rsa->flags&= ~RSA_FLAG_BLINDING;
305 	}
306 
307 int RSA_blinding_on(RSA *rsa, BN_CTX *p_ctx)
308 	{
309 	BIGNUM *A,*Ai;
310 	BN_CTX *ctx;
311 	int ret=0;
312 
313 	if (p_ctx == NULL)
314 		{
315 		if ((ctx=BN_CTX_new()) == NULL) goto err;
316 		}
317 	else
318 		ctx=p_ctx;
319 
320 	if (rsa->blinding != NULL)
321 		BN_BLINDING_free(rsa->blinding);
322 
323 	BN_CTX_start(ctx);
324 	A = BN_CTX_get(ctx);
325 	if (!BN_rand_range(A,rsa->n)) goto err;
326 	if ((Ai=BN_mod_inverse(NULL,A,rsa->n,ctx)) == NULL) goto err;
327 
328 	if (!rsa->meth->bn_mod_exp(A,A,rsa->e,rsa->n,ctx,rsa->_method_mod_n))
329 	    goto err;
330 	rsa->blinding=BN_BLINDING_new(A,Ai,rsa->n);
331 	rsa->flags|=RSA_FLAG_BLINDING;
332 	BN_free(Ai);
333 	ret=1;
334 err:
335 	BN_CTX_end(ctx);
336 	if (ctx != p_ctx) BN_CTX_free(ctx);
337 	return(ret);
338 	}
339 
340 int RSA_memory_lock(RSA *r)
341 	{
342 	int i,j,k,off;
343 	char *p;
344 	BIGNUM *bn,**t[6],*b;
345 	BN_ULONG *ul;
346 
347 	if (r->d == NULL) return(1);
348 	t[0]= &r->d;
349 	t[1]= &r->p;
350 	t[2]= &r->q;
351 	t[3]= &r->dmp1;
352 	t[4]= &r->dmq1;
353 	t[5]= &r->iqmp;
354 	k=sizeof(BIGNUM)*6;
355 	off=k/sizeof(BN_ULONG)+1;
356 	j=1;
357 	for (i=0; i<6; i++)
358 		j+= (*t[i])->top;
359 	if ((p=OPENSSL_malloc_locked((off+j)*sizeof(BN_ULONG))) == NULL)
360 		{
361 		RSAerr(RSA_F_MEMORY_LOCK,ERR_R_MALLOC_FAILURE);
362 		return(0);
363 		}
364 	bn=(BIGNUM *)p;
365 	ul=(BN_ULONG *)&(p[off]);
366 	for (i=0; i<6; i++)
367 		{
368 		b= *(t[i]);
369 		*(t[i])= &(bn[i]);
370 		memcpy((char *)&(bn[i]),(char *)b,sizeof(BIGNUM));
371 		bn[i].flags=BN_FLG_STATIC_DATA;
372 		bn[i].d=ul;
373 		memcpy((char *)ul,b->d,sizeof(BN_ULONG)*b->top);
374 		ul+=b->top;
375 		BN_clear_free(b);
376 		}
377 
378 	/* I should fix this so it can still be done */
379 	r->flags&= ~(RSA_FLAG_CACHE_PRIVATE|RSA_FLAG_CACHE_PUBLIC);
380 
381 	r->bignum_data=p;
382 	return(1);
383 	}
384