Separate DSA functionality from ASN.1 encoding.

[openssl.git] / crypto / dsa / dsa_vrf.c

diff --git a/crypto/dsa/dsa_vrf.c b/crypto/dsa/dsa_vrf.c
index 37e8781dd621f3cccffbdb8f1faa78ecf58ac82e..3b74c81a576f611468f0fcfb89aa657573895715 100644 (file)
--- a/crypto/dsa/dsa_vrf.c
+++ b/crypto/dsa/dsa_vrf.c
@@ -56,7 +56,7 @@
  * [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"
@@ -66,57 +66,34 @@
 #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,u1,u2,t1;
-       ASN1_INTEGER *bs=NULL;
+       BIGNUM u1,u2,t1;
        BN_MONT_CTX *mont=NULL;
        int ret = -1;
 
        if ((ctx=BN_CTX_new()) == NULL) goto err;
-
        BN_init(&u1);
        BN_init(&u2);
-       BN_init(&r);
        BN_init(&t1);
 
-       M_ASN1_D2I_Init();
-       M_ASN1_D2I_start_sequence();
-        M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
-        if ((BN_bin2bn(bs->data,bs->length,&r)) == NULL) goto err_bn;
-        M_ASN1_D2I_get(bs,d2i_ASN1_INTEGER);
-        if ((BN_bin2bn(bs->data,bs->length,&u1)) == NULL) goto err_bn;
-       if (!asn1_Finish(&c)) goto err;
-
        /* Calculate W = inv(S) mod Q
         * save W in u2 */
-       if ((BN_mod_inverse(&u2,&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))
                {
@@ -133,42 +110,59 @@ DSA *dsa;
        BN_init(&t2);
        /* v = ( g^u1 * y^u2 mod p ) mod q */
        /* let t1 = g ^ u1 mod p */
-       if (!BN_mod_exp_mont(&t1,dsa->g,&u1,dsa->p,ctx,mont)) 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_mont(&t2,dsa->pub_key,&u2,dsa->p,ctx,mont)) 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;
        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;
+               goto err;
        /* BN_copy(&u1,&t1); */
        /* let u1 = u1 mod q */
-       if (!BN_mod(&u1,&t1,dsa->q,ctx)) goto err_bn;
+       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);
-       BN_free(&r);
        BN_free(&u1);
        BN_free(&u2);
        BN_free(&t1);
-       if (bs != NULL) ASN1_BIT_STRING_free(bs);
+       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);
        }