xref: /onnv-gate/usr/src/common/openssl/crypto/dsa/dsa_ossl.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /* crypto/dsa/dsa_ossl.c */
2*0Sstevel@tonic-gate /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3*0Sstevel@tonic-gate  * All rights reserved.
4*0Sstevel@tonic-gate  *
5*0Sstevel@tonic-gate  * This package is an SSL implementation written
6*0Sstevel@tonic-gate  * by Eric Young (eay@cryptsoft.com).
7*0Sstevel@tonic-gate  * The implementation was written so as to conform with Netscapes SSL.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * This library is free for commercial and non-commercial use as long as
10*0Sstevel@tonic-gate  * the following conditions are aheared to.  The following conditions
11*0Sstevel@tonic-gate  * apply to all code found in this distribution, be it the RC4, RSA,
12*0Sstevel@tonic-gate  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13*0Sstevel@tonic-gate  * included with this distribution is covered by the same copyright terms
14*0Sstevel@tonic-gate  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15*0Sstevel@tonic-gate  *
16*0Sstevel@tonic-gate  * Copyright remains Eric Young's, and as such any Copyright notices in
17*0Sstevel@tonic-gate  * the code are not to be removed.
18*0Sstevel@tonic-gate  * If this package is used in a product, Eric Young should be given attribution
19*0Sstevel@tonic-gate  * as the author of the parts of the library used.
20*0Sstevel@tonic-gate  * This can be in the form of a textual message at program startup or
21*0Sstevel@tonic-gate  * in documentation (online or textual) provided with the package.
22*0Sstevel@tonic-gate  *
23*0Sstevel@tonic-gate  * Redistribution and use in source and binary forms, with or without
24*0Sstevel@tonic-gate  * modification, are permitted provided that the following conditions
25*0Sstevel@tonic-gate  * are met:
26*0Sstevel@tonic-gate  * 1. Redistributions of source code must retain the copyright
27*0Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer.
28*0Sstevel@tonic-gate  * 2. Redistributions in binary form must reproduce the above copyright
29*0Sstevel@tonic-gate  *    notice, this list of conditions and the following disclaimer in the
30*0Sstevel@tonic-gate  *    documentation and/or other materials provided with the distribution.
31*0Sstevel@tonic-gate  * 3. All advertising materials mentioning features or use of this software
32*0Sstevel@tonic-gate  *    must display the following acknowledgement:
33*0Sstevel@tonic-gate  *    "This product includes cryptographic software written by
34*0Sstevel@tonic-gate  *     Eric Young (eay@cryptsoft.com)"
35*0Sstevel@tonic-gate  *    The word 'cryptographic' can be left out if the rouines from the library
36*0Sstevel@tonic-gate  *    being used are not cryptographic related :-).
37*0Sstevel@tonic-gate  * 4. If you include any Windows specific code (or a derivative thereof) from
38*0Sstevel@tonic-gate  *    the apps directory (application code) you must include an acknowledgement:
39*0Sstevel@tonic-gate  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40*0Sstevel@tonic-gate  *
41*0Sstevel@tonic-gate  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42*0Sstevel@tonic-gate  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43*0Sstevel@tonic-gate  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44*0Sstevel@tonic-gate  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45*0Sstevel@tonic-gate  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46*0Sstevel@tonic-gate  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47*0Sstevel@tonic-gate  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48*0Sstevel@tonic-gate  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49*0Sstevel@tonic-gate  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50*0Sstevel@tonic-gate  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51*0Sstevel@tonic-gate  * SUCH DAMAGE.
52*0Sstevel@tonic-gate  *
53*0Sstevel@tonic-gate  * The licence and distribution terms for any publically available version or
54*0Sstevel@tonic-gate  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55*0Sstevel@tonic-gate  * copied and put under another distribution licence
56*0Sstevel@tonic-gate  * [including the GNU Public Licence.]
57*0Sstevel@tonic-gate  */
58*0Sstevel@tonic-gate 
59*0Sstevel@tonic-gate /* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
60*0Sstevel@tonic-gate 
61*0Sstevel@tonic-gate #include <stdio.h>
62*0Sstevel@tonic-gate #include "cryptlib.h"
63*0Sstevel@tonic-gate #include <openssl/bn.h>
64*0Sstevel@tonic-gate #include <openssl/dsa.h>
65*0Sstevel@tonic-gate #include <openssl/rand.h>
66*0Sstevel@tonic-gate #include <openssl/asn1.h>
67*0Sstevel@tonic-gate 
68*0Sstevel@tonic-gate static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa);
69*0Sstevel@tonic-gate static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp);
70*0Sstevel@tonic-gate static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
71*0Sstevel@tonic-gate 		  DSA *dsa);
72*0Sstevel@tonic-gate static int dsa_init(DSA *dsa);
73*0Sstevel@tonic-gate static int dsa_finish(DSA *dsa);
74*0Sstevel@tonic-gate static int dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1, BIGNUM *p1,
75*0Sstevel@tonic-gate 		BIGNUM *a2, BIGNUM *p2, BIGNUM *m, BN_CTX *ctx,
76*0Sstevel@tonic-gate 		BN_MONT_CTX *in_mont);
77*0Sstevel@tonic-gate static int dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
78*0Sstevel@tonic-gate 				const BIGNUM *m, BN_CTX *ctx,
79*0Sstevel@tonic-gate 				BN_MONT_CTX *m_ctx);
80*0Sstevel@tonic-gate 
81*0Sstevel@tonic-gate static DSA_METHOD openssl_dsa_meth = {
82*0Sstevel@tonic-gate "OpenSSL DSA method",
83*0Sstevel@tonic-gate dsa_do_sign,
84*0Sstevel@tonic-gate dsa_sign_setup,
85*0Sstevel@tonic-gate dsa_do_verify,
86*0Sstevel@tonic-gate dsa_mod_exp,
87*0Sstevel@tonic-gate dsa_bn_mod_exp,
88*0Sstevel@tonic-gate dsa_init,
89*0Sstevel@tonic-gate dsa_finish,
90*0Sstevel@tonic-gate 0,
91*0Sstevel@tonic-gate NULL
92*0Sstevel@tonic-gate };
93*0Sstevel@tonic-gate 
94*0Sstevel@tonic-gate const DSA_METHOD *DSA_OpenSSL(void)
95*0Sstevel@tonic-gate {
96*0Sstevel@tonic-gate 	return &openssl_dsa_meth;
97*0Sstevel@tonic-gate }
98*0Sstevel@tonic-gate 
99*0Sstevel@tonic-gate static DSA_SIG *dsa_do_sign(const unsigned char *dgst, int dlen, DSA *dsa)
100*0Sstevel@tonic-gate 	{
101*0Sstevel@tonic-gate 	BIGNUM *kinv=NULL,*r=NULL,*s=NULL;
102*0Sstevel@tonic-gate 	BIGNUM m;
103*0Sstevel@tonic-gate 	BIGNUM xr;
104*0Sstevel@tonic-gate 	BN_CTX *ctx=NULL;
105*0Sstevel@tonic-gate 	int i,reason=ERR_R_BN_LIB;
106*0Sstevel@tonic-gate 	DSA_SIG *ret=NULL;
107*0Sstevel@tonic-gate 
108*0Sstevel@tonic-gate 	BN_init(&m);
109*0Sstevel@tonic-gate 	BN_init(&xr);
110*0Sstevel@tonic-gate 
111*0Sstevel@tonic-gate 	if (!dsa->p || !dsa->q || !dsa->g)
112*0Sstevel@tonic-gate 		{
113*0Sstevel@tonic-gate 		reason=DSA_R_MISSING_PARAMETERS;
114*0Sstevel@tonic-gate 		goto err;
115*0Sstevel@tonic-gate 		}
116*0Sstevel@tonic-gate 
117*0Sstevel@tonic-gate 	s=BN_new();
118*0Sstevel@tonic-gate 	if (s == NULL) goto err;
119*0Sstevel@tonic-gate 
120*0Sstevel@tonic-gate 	i=BN_num_bytes(dsa->q); /* should be 20 */
121*0Sstevel@tonic-gate 	if ((dlen > i) || (dlen > 50))
122*0Sstevel@tonic-gate 		{
123*0Sstevel@tonic-gate 		reason=DSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
124*0Sstevel@tonic-gate 		goto err;
125*0Sstevel@tonic-gate 		}
126*0Sstevel@tonic-gate 
127*0Sstevel@tonic-gate 	ctx=BN_CTX_new();
128*0Sstevel@tonic-gate 	if (ctx == NULL) goto err;
129*0Sstevel@tonic-gate 
130*0Sstevel@tonic-gate 	if ((dsa->kinv == NULL) || (dsa->r == NULL))
131*0Sstevel@tonic-gate 		{
132*0Sstevel@tonic-gate 		if (!DSA_sign_setup(dsa,ctx,&kinv,&r)) goto err;
133*0Sstevel@tonic-gate 		}
134*0Sstevel@tonic-gate 	else
135*0Sstevel@tonic-gate 		{
136*0Sstevel@tonic-gate 		kinv=dsa->kinv;
137*0Sstevel@tonic-gate 		dsa->kinv=NULL;
138*0Sstevel@tonic-gate 		r=dsa->r;
139*0Sstevel@tonic-gate 		dsa->r=NULL;
140*0Sstevel@tonic-gate 		}
141*0Sstevel@tonic-gate 
142*0Sstevel@tonic-gate 	if (BN_bin2bn(dgst,dlen,&m) == NULL) goto err;
143*0Sstevel@tonic-gate 
144*0Sstevel@tonic-gate 	/* Compute  s = inv(k) (m + xr) mod q */
145*0Sstevel@tonic-gate 	if (!BN_mod_mul(&xr,dsa->priv_key,r,dsa->q,ctx)) goto err;/* s = xr */
146*0Sstevel@tonic-gate 	if (!BN_add(s, &xr, &m)) goto err;		/* s = m + xr */
147*0Sstevel@tonic-gate 	if (BN_cmp(s,dsa->q) > 0)
148*0Sstevel@tonic-gate 		BN_sub(s,s,dsa->q);
149*0Sstevel@tonic-gate 	if (!BN_mod_mul(s,s,kinv,dsa->q,ctx)) goto err;
150*0Sstevel@tonic-gate 
151*0Sstevel@tonic-gate 	ret=DSA_SIG_new();
152*0Sstevel@tonic-gate 	if (ret == NULL) goto err;
153*0Sstevel@tonic-gate 	ret->r = r;
154*0Sstevel@tonic-gate 	ret->s = s;
155*0Sstevel@tonic-gate 
156*0Sstevel@tonic-gate err:
157*0Sstevel@tonic-gate 	if (!ret)
158*0Sstevel@tonic-gate 		{
159*0Sstevel@tonic-gate 		DSAerr(DSA_F_DSA_DO_SIGN,reason);
160*0Sstevel@tonic-gate 		BN_free(r);
161*0Sstevel@tonic-gate 		BN_free(s);
162*0Sstevel@tonic-gate 		}
163*0Sstevel@tonic-gate 	if (ctx != NULL) BN_CTX_free(ctx);
164*0Sstevel@tonic-gate 	BN_clear_free(&m);
165*0Sstevel@tonic-gate 	BN_clear_free(&xr);
166*0Sstevel@tonic-gate 	if (kinv != NULL) /* dsa->kinv is NULL now if we used it */
167*0Sstevel@tonic-gate 	    BN_clear_free(kinv);
168*0Sstevel@tonic-gate 	return(ret);
169*0Sstevel@tonic-gate 	}
170*0Sstevel@tonic-gate 
171*0Sstevel@tonic-gate static int dsa_sign_setup(DSA *dsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
172*0Sstevel@tonic-gate 	{
173*0Sstevel@tonic-gate 	BN_CTX *ctx;
174*0Sstevel@tonic-gate 	BIGNUM k,*kinv=NULL,*r=NULL;
175*0Sstevel@tonic-gate 	int ret=0;
176*0Sstevel@tonic-gate 
177*0Sstevel@tonic-gate 	if (!dsa->p || !dsa->q || !dsa->g)
178*0Sstevel@tonic-gate 		{
179*0Sstevel@tonic-gate 		DSAerr(DSA_F_DSA_SIGN_SETUP,DSA_R_MISSING_PARAMETERS);
180*0Sstevel@tonic-gate 		return 0;
181*0Sstevel@tonic-gate 		}
182*0Sstevel@tonic-gate 
183*0Sstevel@tonic-gate 	BN_init(&k);
184*0Sstevel@tonic-gate 
185*0Sstevel@tonic-gate 	if (ctx_in == NULL)
186*0Sstevel@tonic-gate 		{
187*0Sstevel@tonic-gate 		if ((ctx=BN_CTX_new()) == NULL) goto err;
188*0Sstevel@tonic-gate 		}
189*0Sstevel@tonic-gate 	else
190*0Sstevel@tonic-gate 		ctx=ctx_in;
191*0Sstevel@tonic-gate 
192*0Sstevel@tonic-gate 	if ((r=BN_new()) == NULL) goto err;
193*0Sstevel@tonic-gate 	kinv=NULL;
194*0Sstevel@tonic-gate 
195*0Sstevel@tonic-gate 	/* Get random k */
196*0Sstevel@tonic-gate 	do
197*0Sstevel@tonic-gate 		if (!BN_rand_range(&k, dsa->q)) goto err;
198*0Sstevel@tonic-gate 	while (BN_is_zero(&k));
199*0Sstevel@tonic-gate 
200*0Sstevel@tonic-gate 	if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
201*0Sstevel@tonic-gate 		{
202*0Sstevel@tonic-gate 		if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
203*0Sstevel@tonic-gate 			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p,
204*0Sstevel@tonic-gate 				dsa->p,ctx)) goto err;
205*0Sstevel@tonic-gate 		}
206*0Sstevel@tonic-gate 
207*0Sstevel@tonic-gate 	/* Compute r = (g^k mod p) mod q */
208*0Sstevel@tonic-gate 	if (!dsa->meth->bn_mod_exp(dsa, r,dsa->g,&k,dsa->p,ctx,
209*0Sstevel@tonic-gate 		(BN_MONT_CTX *)dsa->method_mont_p)) goto err;
210*0Sstevel@tonic-gate 	if (!BN_mod(r,r,dsa->q,ctx)) goto err;
211*0Sstevel@tonic-gate 
212*0Sstevel@tonic-gate 	/* Compute  part of 's = inv(k) (m + xr) mod q' */
213*0Sstevel@tonic-gate 	if ((kinv=BN_mod_inverse(NULL,&k,dsa->q,ctx)) == NULL) goto err;
214*0Sstevel@tonic-gate 
215*0Sstevel@tonic-gate 	if (*kinvp != NULL) BN_clear_free(*kinvp);
216*0Sstevel@tonic-gate 	*kinvp=kinv;
217*0Sstevel@tonic-gate 	kinv=NULL;
218*0Sstevel@tonic-gate 	if (*rp != NULL) BN_clear_free(*rp);
219*0Sstevel@tonic-gate 	*rp=r;
220*0Sstevel@tonic-gate 	ret=1;
221*0Sstevel@tonic-gate err:
222*0Sstevel@tonic-gate 	if (!ret)
223*0Sstevel@tonic-gate 		{
224*0Sstevel@tonic-gate 		DSAerr(DSA_F_DSA_SIGN_SETUP,ERR_R_BN_LIB);
225*0Sstevel@tonic-gate 		if (kinv != NULL) BN_clear_free(kinv);
226*0Sstevel@tonic-gate 		if (r != NULL) BN_clear_free(r);
227*0Sstevel@tonic-gate 		}
228*0Sstevel@tonic-gate 	if (ctx_in == NULL) BN_CTX_free(ctx);
229*0Sstevel@tonic-gate 	if (kinv != NULL) BN_clear_free(kinv);
230*0Sstevel@tonic-gate 	BN_clear_free(&k);
231*0Sstevel@tonic-gate 	return(ret);
232*0Sstevel@tonic-gate 	}
233*0Sstevel@tonic-gate 
234*0Sstevel@tonic-gate static int dsa_do_verify(const unsigned char *dgst, int dgst_len, DSA_SIG *sig,
235*0Sstevel@tonic-gate 		  DSA *dsa)
236*0Sstevel@tonic-gate 	{
237*0Sstevel@tonic-gate 	BN_CTX *ctx;
238*0Sstevel@tonic-gate 	BIGNUM u1,u2,t1;
239*0Sstevel@tonic-gate 	BN_MONT_CTX *mont=NULL;
240*0Sstevel@tonic-gate 	int ret = -1;
241*0Sstevel@tonic-gate 	if (!dsa->p || !dsa->q || !dsa->g)
242*0Sstevel@tonic-gate 		{
243*0Sstevel@tonic-gate 		DSAerr(DSA_F_DSA_DO_VERIFY,DSA_R_MISSING_PARAMETERS);
244*0Sstevel@tonic-gate 		return -1;
245*0Sstevel@tonic-gate 		}
246*0Sstevel@tonic-gate 
247*0Sstevel@tonic-gate 	BN_init(&u1);
248*0Sstevel@tonic-gate 	BN_init(&u2);
249*0Sstevel@tonic-gate 	BN_init(&t1);
250*0Sstevel@tonic-gate 
251*0Sstevel@tonic-gate 	if ((ctx=BN_CTX_new()) == NULL) goto err;
252*0Sstevel@tonic-gate 
253*0Sstevel@tonic-gate 	if (BN_is_zero(sig->r) || sig->r->neg || BN_ucmp(sig->r, dsa->q) >= 0)
254*0Sstevel@tonic-gate 		{
255*0Sstevel@tonic-gate 		ret = 0;
256*0Sstevel@tonic-gate 		goto err;
257*0Sstevel@tonic-gate 		}
258*0Sstevel@tonic-gate 	if (BN_is_zero(sig->s) || sig->s->neg || BN_ucmp(sig->s, dsa->q) >= 0)
259*0Sstevel@tonic-gate 		{
260*0Sstevel@tonic-gate 		ret = 0;
261*0Sstevel@tonic-gate 		goto err;
262*0Sstevel@tonic-gate 		}
263*0Sstevel@tonic-gate 
264*0Sstevel@tonic-gate 	/* Calculate W = inv(S) mod Q
265*0Sstevel@tonic-gate 	 * save W in u2 */
266*0Sstevel@tonic-gate 	if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
267*0Sstevel@tonic-gate 
268*0Sstevel@tonic-gate 	/* save M in u1 */
269*0Sstevel@tonic-gate 	if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
270*0Sstevel@tonic-gate 
271*0Sstevel@tonic-gate 	/* u1 = M * w mod q */
272*0Sstevel@tonic-gate 	if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
273*0Sstevel@tonic-gate 
274*0Sstevel@tonic-gate 	/* u2 = r * w mod q */
275*0Sstevel@tonic-gate 	if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
276*0Sstevel@tonic-gate 
277*0Sstevel@tonic-gate 	if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
278*0Sstevel@tonic-gate 		{
279*0Sstevel@tonic-gate 		if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
280*0Sstevel@tonic-gate 			if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p,
281*0Sstevel@tonic-gate 				dsa->p,ctx)) goto err;
282*0Sstevel@tonic-gate 		}
283*0Sstevel@tonic-gate 	mont=(BN_MONT_CTX *)dsa->method_mont_p;
284*0Sstevel@tonic-gate 
285*0Sstevel@tonic-gate #if 0
286*0Sstevel@tonic-gate 	{
287*0Sstevel@tonic-gate 	BIGNUM t2;
288*0Sstevel@tonic-gate 
289*0Sstevel@tonic-gate 	BN_init(&t2);
290*0Sstevel@tonic-gate 	/* v = ( g^u1 * y^u2 mod p ) mod q */
291*0Sstevel@tonic-gate 	/* let t1 = g ^ u1 mod p */
292*0Sstevel@tonic-gate 	if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err;
293*0Sstevel@tonic-gate 	/* let t2 = y ^ u2 mod p */
294*0Sstevel@tonic-gate 	if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err;
295*0Sstevel@tonic-gate 	/* let u1 = t1 * t2 mod p */
296*0Sstevel@tonic-gate 	if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn;
297*0Sstevel@tonic-gate 	BN_free(&t2);
298*0Sstevel@tonic-gate 	}
299*0Sstevel@tonic-gate 	/* let u1 = u1 mod q */
300*0Sstevel@tonic-gate 	if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err;
301*0Sstevel@tonic-gate #else
302*0Sstevel@tonic-gate 	{
303*0Sstevel@tonic-gate 	if (!dsa->meth->dsa_mod_exp(dsa, &t1,dsa->g,&u1,dsa->pub_key,&u2,
304*0Sstevel@tonic-gate 						dsa->p,ctx,mont)) goto err;
305*0Sstevel@tonic-gate 	/* BN_copy(&u1,&t1); */
306*0Sstevel@tonic-gate 	/* let u1 = u1 mod q */
307*0Sstevel@tonic-gate 	if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
308*0Sstevel@tonic-gate 	}
309*0Sstevel@tonic-gate #endif
310*0Sstevel@tonic-gate 	/* V is now in u1.  If the signature is correct, it will be
311*0Sstevel@tonic-gate 	 * equal to R. */
312*0Sstevel@tonic-gate 	ret=(BN_ucmp(&u1, sig->r) == 0);
313*0Sstevel@tonic-gate 
314*0Sstevel@tonic-gate 	err:
315*0Sstevel@tonic-gate 	if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
316*0Sstevel@tonic-gate 	if (ctx != NULL) BN_CTX_free(ctx);
317*0Sstevel@tonic-gate 	BN_free(&u1);
318*0Sstevel@tonic-gate 	BN_free(&u2);
319*0Sstevel@tonic-gate 	BN_free(&t1);
320*0Sstevel@tonic-gate 	return(ret);
321*0Sstevel@tonic-gate 	}
322*0Sstevel@tonic-gate 
323*0Sstevel@tonic-gate static int dsa_init(DSA *dsa)
324*0Sstevel@tonic-gate {
325*0Sstevel@tonic-gate 	dsa->flags|=DSA_FLAG_CACHE_MONT_P;
326*0Sstevel@tonic-gate 	return(1);
327*0Sstevel@tonic-gate }
328*0Sstevel@tonic-gate 
329*0Sstevel@tonic-gate static int dsa_finish(DSA *dsa)
330*0Sstevel@tonic-gate {
331*0Sstevel@tonic-gate 	if(dsa->method_mont_p)
332*0Sstevel@tonic-gate 		BN_MONT_CTX_free((BN_MONT_CTX *)dsa->method_mont_p);
333*0Sstevel@tonic-gate 	return(1);
334*0Sstevel@tonic-gate }
335*0Sstevel@tonic-gate 
336*0Sstevel@tonic-gate static int dsa_mod_exp(DSA *dsa, BIGNUM *rr, BIGNUM *a1, BIGNUM *p1,
337*0Sstevel@tonic-gate 		BIGNUM *a2, BIGNUM *p2, BIGNUM *m, BN_CTX *ctx,
338*0Sstevel@tonic-gate 		BN_MONT_CTX *in_mont)
339*0Sstevel@tonic-gate {
340*0Sstevel@tonic-gate 	return BN_mod_exp2_mont(rr, a1, p1, a2, p2, m, ctx, in_mont);
341*0Sstevel@tonic-gate }
342*0Sstevel@tonic-gate 
343*0Sstevel@tonic-gate static int dsa_bn_mod_exp(DSA *dsa, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
344*0Sstevel@tonic-gate 				const BIGNUM *m, BN_CTX *ctx,
345*0Sstevel@tonic-gate 				BN_MONT_CTX *m_ctx)
346*0Sstevel@tonic-gate {
347*0Sstevel@tonic-gate 	return BN_mod_exp_mont(r, a, p, m, ctx, m_ctx);
348*0Sstevel@tonic-gate }
349