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/rand.h>
66#ifndef OPENSSL_NO_ENGINE
67#include <openssl/engine.h>
68#endif
69
70const char RSA_version[]="RSA" OPENSSL_VERSION_PTEXT;
71
72static const RSA_METHOD *default_RSA_meth=NULL;
73
74RSA *RSA_new(void)
75	{
76	RSA *r=RSA_new_method(NULL);
77
78	return r;
79	}
80
81void RSA_set_default_method(const RSA_METHOD *meth)
82	{
83	default_RSA_meth = meth;
84	}
85
86const RSA_METHOD *RSA_get_default_method(void)
87	{
88	if (default_RSA_meth == NULL)
89		{
90#ifdef RSA_NULL
91		default_RSA_meth=RSA_null_method();
92#else
93#if 0 /* was: #ifdef RSAref */
94		default_RSA_meth=RSA_PKCS1_RSAref();
95#else
96		default_RSA_meth=RSA_PKCS1_SSLeay();
97#endif
98#endif
99		}
100
101	return default_RSA_meth;
102	}
103
104const RSA_METHOD *RSA_get_method(const RSA *rsa)
105	{
106	return rsa->meth;
107	}
108
109int RSA_set_method(RSA *rsa, const RSA_METHOD *meth)
110	{
111	/* NB: The caller is specifically setting a method, so it's not up to us
112	 * to deal with which ENGINE it comes from. */
113	const RSA_METHOD *mtmp;
114	mtmp = rsa->meth;
115	if (mtmp->finish) mtmp->finish(rsa);
116#ifndef OPENSSL_NO_ENGINE
117	if (rsa->engine)
118		{
119		ENGINE_finish(rsa->engine);
120		rsa->engine = NULL;
121		}
122#endif
123	rsa->meth = meth;
124	if (meth->init) meth->init(rsa);
125	return 1;
126	}
127
128RSA *RSA_new_method(ENGINE *engine)
129	{
130	RSA *ret;
131
132	ret=(RSA *)OPENSSL_malloc(sizeof(RSA));
133	if (ret == NULL)
134		{
135		RSAerr(RSA_F_RSA_NEW_METHOD,ERR_R_MALLOC_FAILURE);
136		return NULL;
137		}
138
139	ret->meth = RSA_get_default_method();
140#ifndef OPENSSL_NO_ENGINE
141	if (engine)
142		{
143		if (!ENGINE_init(engine))
144			{
145			RSAerr(RSA_F_RSA_NEW_METHOD, ERR_R_ENGINE_LIB);
146			OPENSSL_free(ret);
147			return NULL;
148			}
149		ret->engine = engine;
150		}
151	else
152		ret->engine = ENGINE_get_default_RSA();
153	if(ret->engine)
154		{
155		ret->meth = ENGINE_get_RSA(ret->engine);
156		if(!ret->meth)
157			{
158			RSAerr(RSA_F_RSA_NEW_METHOD,
159				ERR_R_ENGINE_LIB);
160			ENGINE_finish(ret->engine);
161			OPENSSL_free(ret);
162			return NULL;
163			}
164		}
165#endif
166
167	ret->pad=0;
168	ret->version=0;
169	ret->n=NULL;
170	ret->e=NULL;
171	ret->d=NULL;
172	ret->p=NULL;
173	ret->q=NULL;
174	ret->dmp1=NULL;
175	ret->dmq1=NULL;
176	ret->iqmp=NULL;
177	ret->references=1;
178	ret->_method_mod_n=NULL;
179	ret->_method_mod_p=NULL;
180	ret->_method_mod_q=NULL;
181	ret->blinding=NULL;
182	ret->mt_blinding=NULL;
183	ret->bignum_data=NULL;
184	ret->flags=ret->meth->flags;
185	if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_RSA, ret, &ret->ex_data))
186		{
187#ifndef OPENSSL_NO_ENGINE
188	if (ret->engine)
189		ENGINE_finish(ret->engine);
190#endif
191		OPENSSL_free(ret);
192		return(NULL);
193		}
194
195	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
196		{
197#ifndef OPENSSL_NO_ENGINE
198		if (ret->engine)
199			ENGINE_finish(ret->engine);
200#endif
201		CRYPTO_free_ex_data(CRYPTO_EX_INDEX_RSA, ret, &ret->ex_data);
202		OPENSSL_free(ret);
203		ret=NULL;
204		}
205	return(ret);
206	}
207
208void RSA_free(RSA *r)
209	{
210	int i;
211
212	if (r == NULL) return;
213
214	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_RSA);
215#ifdef REF_PRINT
216	REF_PRINT("RSA",r);
217#endif
218	if (i > 0) return;
219#ifdef REF_CHECK
220	if (i < 0)
221		{
222		fprintf(stderr,"RSA_free, bad reference count\n");
223		abort();
224		}
225#endif
226
227	if (r->meth->finish)
228		r->meth->finish(r);
229#ifndef OPENSSL_NO_ENGINE
230	if (r->engine)
231		ENGINE_finish(r->engine);
232#endif
233
234	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_RSA, r, &r->ex_data);
235
236	if (r->n != NULL) BN_clear_free(r->n);
237	if (r->e != NULL) BN_clear_free(r->e);
238	if (r->d != NULL) BN_clear_free(r->d);
239	if (r->p != NULL) BN_clear_free(r->p);
240	if (r->q != NULL) BN_clear_free(r->q);
241	if (r->dmp1 != NULL) BN_clear_free(r->dmp1);
242	if (r->dmq1 != NULL) BN_clear_free(r->dmq1);
243	if (r->iqmp != NULL) BN_clear_free(r->iqmp);
244	if (r->blinding != NULL) BN_BLINDING_free(r->blinding);
245	if (r->mt_blinding != NULL) BN_BLINDING_free(r->mt_blinding);
246	if (r->bignum_data != NULL) OPENSSL_free_locked(r->bignum_data);
247	OPENSSL_free(r);
248	}
249
250int RSA_up_ref(RSA *r)
251	{
252	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_RSA);
253#ifdef REF_PRINT
254	REF_PRINT("RSA",r);
255#endif
256#ifdef REF_CHECK
257	if (i < 2)
258		{
259		fprintf(stderr, "RSA_up_ref, bad reference count\n");
260		abort();
261		}
262#endif
263	return ((i > 1) ? 1 : 0);
264	}
265
266int RSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
267	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
268        {
269	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_RSA, argl, argp,
270				new_func, dup_func, free_func);
271        }
272
273int RSA_set_ex_data(RSA *r, int idx, void *arg)
274	{
275	return(CRYPTO_set_ex_data(&r->ex_data,idx,arg));
276	}
277
278void *RSA_get_ex_data(const RSA *r, int idx)
279	{
280	return(CRYPTO_get_ex_data(&r->ex_data,idx));
281	}
282
283int RSA_size(const RSA *r)
284	{
285	return(BN_num_bytes(r->n));
286	}
287
288int RSA_public_encrypt(int flen, const unsigned char *from, unsigned char *to,
289	     RSA *rsa, int padding)
290	{
291	return(rsa->meth->rsa_pub_enc(flen, from, to, rsa, padding));
292	}
293
294int RSA_private_encrypt(int flen, const unsigned char *from, unsigned char *to,
295	     RSA *rsa, int padding)
296	{
297	return(rsa->meth->rsa_priv_enc(flen, from, to, rsa, padding));
298	}
299
300int RSA_private_decrypt(int flen, const unsigned char *from, unsigned char *to,
301	     RSA *rsa, int padding)
302	{
303	return(rsa->meth->rsa_priv_dec(flen, from, to, rsa, padding));
304	}
305
306int RSA_public_decrypt(int flen, const unsigned char *from, unsigned char *to,
307	     RSA *rsa, int padding)
308	{
309	return(rsa->meth->rsa_pub_dec(flen, from, to, rsa, padding));
310	}
311
312int RSA_flags(const RSA *r)
313	{
314	return((r == NULL)?0:r->meth->flags);
315	}
316
317void RSA_blinding_off(RSA *rsa)
318	{
319	if (rsa->blinding != NULL)
320		{
321		BN_BLINDING_free(rsa->blinding);
322		rsa->blinding=NULL;
323		}
324	rsa->flags &= ~RSA_FLAG_BLINDING;
325	rsa->flags |= RSA_FLAG_NO_BLINDING;
326	}
327
328int RSA_blinding_on(RSA *rsa, BN_CTX *ctx)
329	{
330	int ret=0;
331
332	if (rsa->blinding != NULL)
333		RSA_blinding_off(rsa);
334
335	rsa->blinding = RSA_setup_blinding(rsa, ctx);
336	if (rsa->blinding == NULL)
337		goto err;
338
339	rsa->flags |= RSA_FLAG_BLINDING;
340	rsa->flags &= ~RSA_FLAG_NO_BLINDING;
341	ret=1;
342err:
343	return(ret);
344	}
345
346static BIGNUM *rsa_get_public_exp(const BIGNUM *d, const BIGNUM *p,
347	const BIGNUM *q, BN_CTX *ctx)
348{
349	BIGNUM *ret = NULL, *r0, *r1, *r2;
350
351	if (d == NULL || p == NULL || q == NULL)
352		return NULL;
353
354	BN_CTX_start(ctx);
355	r0 = BN_CTX_get(ctx);
356	r1 = BN_CTX_get(ctx);
357	r2 = BN_CTX_get(ctx);
358	if (r2 == NULL)
359		goto err;
360
361	if (!BN_sub(r1, p, BN_value_one())) goto err;
362	if (!BN_sub(r2, q, BN_value_one())) goto err;
363	if (!BN_mul(r0, r1, r2, ctx)) goto err;
364
365	ret = BN_mod_inverse(NULL, d, r0, ctx);
366err:
367	BN_CTX_end(ctx);
368	return ret;
369}
370
371BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
372{
373	BIGNUM local_n;
374	BIGNUM *e,*n;
375	BN_CTX *ctx;
376	BN_BLINDING *ret = NULL;
377
378	if (in_ctx == NULL)
379		{
380		if ((ctx = BN_CTX_new()) == NULL) return 0;
381		}
382	else
383		ctx = in_ctx;
384
385	BN_CTX_start(ctx);
386	e  = BN_CTX_get(ctx);
387	if (e == NULL)
388		{
389		RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
390		goto err;
391		}
392
393	if (rsa->e == NULL)
394		{
395		e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
396		if (e == NULL)
397			{
398			RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
399			goto err;
400			}
401		}
402	else
403		e = rsa->e;
404
405
406	if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
407		{
408		/* if PRNG is not properly seeded, resort to secret
409		 * exponent as unpredictable seed */
410		RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0.0);
411		}
412
413	if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
414		{
415		/* Set BN_FLG_CONSTTIME flag */
416		n = &local_n;
417		BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
418		}
419	else
420		n = rsa->n;
421
422	ret = BN_BLINDING_create_param(NULL, e, n, ctx,
423			rsa->meth->bn_mod_exp, rsa->_method_mod_n);
424	if (ret == NULL)
425		{
426		RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
427		goto err;
428		}
429	CRYPTO_THREADID_current(BN_BLINDING_thread_id(ret));
430err:
431	BN_CTX_end(ctx);
432	if (in_ctx == NULL)
433		BN_CTX_free(ctx);
434	if(rsa->e == NULL)
435		BN_free(e);
436
437	return ret;
438}
439
440int RSA_memory_lock(RSA *r)
441	{
442	int i,j,k,off;
443	char *p;
444	BIGNUM *bn,**t[6],*b;
445	BN_ULONG *ul;
446
447	if (r->d == NULL) return(1);
448	t[0]= &r->d;
449	t[1]= &r->p;
450	t[2]= &r->q;
451	t[3]= &r->dmp1;
452	t[4]= &r->dmq1;
453	t[5]= &r->iqmp;
454	k=sizeof(BIGNUM)*6;
455	off=k/sizeof(BN_ULONG)+1;
456	j=1;
457	for (i=0; i<6; i++)
458		j+= (*t[i])->top;
459	if ((p=OPENSSL_malloc_locked((off+j)*sizeof(BN_ULONG))) == NULL)
460		{
461		RSAerr(RSA_F_RSA_MEMORY_LOCK,ERR_R_MALLOC_FAILURE);
462		return(0);
463		}
464	bn=(BIGNUM *)p;
465	ul=(BN_ULONG *)&(p[off]);
466	for (i=0; i<6; i++)
467		{
468		b= *(t[i]);
469		*(t[i])= &(bn[i]);
470		memcpy((char *)&(bn[i]),(char *)b,sizeof(BIGNUM));
471		bn[i].flags=BN_FLG_STATIC_DATA;
472		bn[i].d=ul;
473		memcpy((char *)ul,b->d,sizeof(BN_ULONG)*b->top);
474		ul+=b->top;
475		BN_clear_free(b);
476		}
477
478	/* I should fix this so it can still be done */
479	r->flags&= ~(RSA_FLAG_CACHE_PRIVATE|RSA_FLAG_CACHE_PUBLIC);
480
481	r->bignum_data=p;
482	return(1);
483	}
484