/* crypto/dsa/dsa_vrf.c */
-/* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com)
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* [including the GNU Public Licence.]
*/
-/* Origional version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
+/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
#include <stdio.h>
#include "cryptlib.h"
#include "asn1.h"
#include "asn1_mac.h"
-/* data has already been hashed (probably with SHA or SHA-1). */
-/* returns
- * 1: correct signature
- * 0: incorrect signature
- * -1: error
- */
-int DSA_verify(type,dgst,dgst_len,sigbuf,siglen, dsa)
-int type;
+int DSA_do_verify(dgst,dgst_len,sig,dsa)
unsigned char *dgst;
int dgst_len;
-unsigned char *sigbuf;
-int siglen;
+DSA_SIG *sig;
DSA *dsa;
{
- /* The next 3 are used by the M_ASN1 macros */
- long length=siglen;
- ASN1_CTX c;
- unsigned char **pp= &sigbuf;
BN_CTX *ctx;
- BIGNUM *r=NULL;
- BIGNUM *t1=NULL,*t2=NULL;
- BIGNUM *u1=NULL,*u2=NULL;
- ASN1_INTEGER *bs=NULL;
+ BIGNUM u1,u2,t1;
+ BN_MONT_CTX *mont=NULL;
int ret = -1;
- ctx=BN_CTX_new();
- if (ctx == NULL) goto err;
-
- t1=BN_new();
- t2=BN_new();
- if (t1 == NULL || t2 == NULL) goto err;
-
- M_ASN1_D2I_Init();
- M_ASN1_D2I_start_sequence();
- M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
- if ((r=BN_bin2bn(bs->data,bs->length,NULL)) == NULL) goto err_bn;
- M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
- if ((u1=BN_bin2bn(bs->data,bs->length,NULL)) == NULL) goto err_bn;
- if (!asn1_Finish(&c)) goto err;
+ if ((ctx=BN_CTX_new()) == NULL) goto err;
+ BN_init(&u1);
+ BN_init(&u2);
+ BN_init(&t1);
/* Calculate W = inv(S) mod Q
* save W in u2 */
- if ((u2=BN_mod_inverse(u1,dsa->q,ctx)) == NULL) goto err_bn;
+ if ((BN_mod_inverse(&u2,sig->s,dsa->q,ctx)) == NULL) goto err;
/* save M in u1 */
- if (BN_bin2bn(dgst,dgst_len,u1) == NULL) goto err_bn;
+ if (BN_bin2bn(dgst,dgst_len,&u1) == NULL) goto err;
/* u1 = M * w mod q */
- if (!BN_mod_mul(u1,u1,u2,dsa->q,ctx)) goto err_bn;
+ if (!BN_mod_mul(&u1,&u1,&u2,dsa->q,ctx)) goto err;
/* u2 = r * w mod q */
- if (!BN_mod_mul(u2,r,u2,dsa->q,ctx)) goto err_bn;
+ if (!BN_mod_mul(&u2,sig->r,&u2,dsa->q,ctx)) goto err;
+
+ if ((dsa->method_mont_p == NULL) && (dsa->flags & DSA_FLAG_CACHE_MONT_P))
+ {
+ if ((dsa->method_mont_p=(char *)BN_MONT_CTX_new()) != NULL)
+ if (!BN_MONT_CTX_set((BN_MONT_CTX *)dsa->method_mont_p,
+ dsa->p,ctx)) goto err;
+ }
+ mont=(BN_MONT_CTX *)dsa->method_mont_p;
+#if 0
+ {
+ BIGNUM t2;
+
+ BN_init(&t2);
/* v = ( g^u1 * y^u2 mod p ) mod q */
/* let t1 = g ^ u1 mod p */
- if (!BN_mod_exp(t1,dsa->g,u1,dsa->p,ctx)) goto err_bn;
+ if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) goto err;
/* let t2 = y ^ u2 mod p */
- if (!BN_mod_exp(t2,dsa->pub_key,u2,dsa->p,ctx)) goto err_bn;
+ if (!BN_mod_exp_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) goto err;
/* let u1 = t1 * t2 mod p */
- if (!BN_mod_mul(u1,t1,t2,dsa->p,ctx)) goto err_bn;
+ if (!BN_mod_mul(&u1,&t1,&t2,dsa->p,ctx)) goto err_bn;
+ BN_free(&t2);
+ }
/* let u1 = u1 mod q */
- if (!BN_mod(u1,u1,dsa->q,ctx)) goto err_bn;
+ if (!BN_mod(&u1,&u1,dsa->q,ctx)) goto err;
+#else
+ {
+ if (!BN_mod_exp2_mont(&t1,dsa->g,&u1,dsa->pub_key,&u2,dsa->p,ctx,mont))
+ goto err;
+ /* BN_copy(&u1,&t1); */
+ /* let u1 = u1 mod q */
+ if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err;
+ }
+#endif
/* V is now in u1. If the signature is correct, it will be
* equal to R. */
- ret=(BN_ucmp(u1, r) == 0);
- if (0)
- {
-err: /* ASN1 error */
- DSAerr(DSA_F_DSA_VERIFY,c.error);
- }
- if (0)
- {
-err_bn: /* BN error */
- DSAerr(DSA_F_DSA_VERIFY,ERR_R_BN_LIB);
- }
+ ret=(BN_ucmp(&u1, sig->r) == 0);
+
+ err:
+ if (ret != 1) DSAerr(DSA_F_DSA_DO_VERIFY,ERR_R_BN_LIB);
if (ctx != NULL) BN_CTX_free(ctx);
- if (r != NULL) BN_free(r);
- if (t1 != NULL) BN_free(t1);
- if (t2 != NULL) BN_free(t2);
- if (u1 != NULL) BN_free(u1);
- if (u2 != NULL) BN_free(u2);
- if (bs != NULL) ASN1_BIT_STRING_free(bs);
+ BN_free(&u1);
+ BN_free(&u2);
+ BN_free(&t1);
+ return(ret);
+ }
+
+/* data has already been hashed (probably with SHA or SHA-1). */
+/* returns
+ * 1: correct signature
+ * 0: incorrect signature
+ * -1: error
+ */
+int DSA_verify(type,dgst,dgst_len,sigbuf,siglen,dsa)
+int type;
+unsigned char *dgst;
+int dgst_len;
+unsigned char *sigbuf;
+int siglen;
+DSA *dsa;
+ {
+ DSA_SIG *s;
+ int ret=-1;
+
+ s = DSA_SIG_new();
+ if (s == NULL) return(ret);
+ if (d2i_DSA_SIG(&s,&sigbuf,siglen) == NULL) goto err;
+ ret=DSA_do_verify(dgst,dgst_len,s,dsa);
+err:
+ DSA_SIG_free(s);
return(ret);
}