implement and use new macros BN_get_sign(), BN_set_sign()
[openssl.git] / crypto / ecdsa / ecs_ossl.c
index 96797f332befb4d53cae0aea076122694a0d902b..215da3892af8e9485c78b670f96d211d279fef76 100644 (file)
  * Hudson (tjh@cryptsoft.com).
  *
  */
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
- *
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- * 
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to.  The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- * 
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- * 
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *    "This product includes cryptographic software written by
- *     Eric Young (eay@cryptsoft.com)"
- *    The word 'cryptographic' can be left out if the rouines from the library
- *    being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from 
- *    the apps directory (application code) you must include an acknowledgement:
- *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- * 
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
- * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
- * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- * 
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed.  i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
- */
-#include "cryptlib.h"
-#include <openssl/ecdsa.h>
 
-/* TODO : general case */
-#define        EC_POINT_get_affine_coordinates EC_POINT_get_affine_coordinates_GFp
+#include "ecdsa.h"
+#include <openssl/err.h>
+#include <openssl/obj_mac.h>
 
-static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, ECDSA *ecdsa);
-static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp);
-static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, ECDSA_SIG *sig,
-                          ECDSA *ecdsa);
+static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, 
+               EC_KEY *eckey);
+static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, 
+               BIGNUM **rp);
+static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, 
+               ECDSA_SIG *sig, EC_KEY *eckey);
 
 static ECDSA_METHOD openssl_ecdsa_meth = {
-"OpenSSL ECDSA method",
-ecdsa_do_sign,
-ecdsa_sign_setup,
-ecdsa_do_verify,
-0,
-NULL
+       "OpenSSL ECDSA method",
+       ecdsa_do_sign,
+       ecdsa_sign_setup,
+       ecdsa_do_verify,
+#if 0
+       NULL, /* init     */
+       NULL, /* finish   */
+#endif
+       0,    /* flags    */
+       NULL  /* app_data */
 };
 
 const ECDSA_METHOD *ECDSA_OpenSSL(void)
@@ -133,35 +82,52 @@ const ECDSA_METHOD *ECDSA_OpenSSL(void)
        return &openssl_ecdsa_meth;
 }
 
-static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM **rp)
+static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
+               BIGNUM **rp)
 {
        BN_CTX   *ctx = NULL;
        BIGNUM   k,*kinv=NULL,*r=NULL,*order=NULL,*X=NULL;
        EC_POINT *tmp_point=NULL;
-       int      ret = 0,reason = ERR_R_BN_LIB;
-       if (!ecdsa  || !ecdsa->group || !ecdsa->pub_key || !ecdsa->priv_key)
+       int      ret = 0;
+       if (!eckey  || !eckey->group || !eckey->pub_key || !eckey->priv_key)
        {
-               reason = ECDSA_R_MISSING_PARAMETERS;
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER);
                return 0;
        }
        if (ctx_in == NULL) 
        {
-               if ((ctx=BN_CTX_new()) == NULL) goto err;
+               if ((ctx=BN_CTX_new()) == NULL)
+               {
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE);
+               goto err;
+               }
        }
        else
                ctx=ctx_in;
 
-       if ((r = BN_new()) == NULL) goto err;
-       if ((order = BN_new()) == NULL) goto err;
-       if ((X = BN_new()) == NULL) goto err;
-       if ((tmp_point = EC_POINT_new(ecdsa->group)) == NULL)
+       if ((r = BN_new()) == NULL)
        {
-               reason = ERR_R_EC_LIB;
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+               goto err;       
+       }
+       if ((order = BN_new()) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+               goto err;       
+       }
+       if ((X = BN_new()) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+               goto err;       
+       }
+       if ((tmp_point = EC_POINT_new(eckey->group)) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
                goto err;
        }
-       if (!EC_GROUP_get_order(ecdsa->group,order,ctx))
+       if (!EC_GROUP_get_order(eckey->group,order,ctx))
        {
-               reason = ERR_R_EC_LIB;
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
                goto err;
        }
        
@@ -172,24 +138,53 @@ static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM
                do
                        if (!BN_rand_range(&k,order))
                        {
-                               reason = ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED;
+                               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
+                                ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED);      
                                goto err;
                        }
                while (BN_is_zero(&k));
 
                /* compute r the x-coordinate of generator * k */
-               if (!EC_POINT_mul(ecdsa->group,tmp_point,&k,NULL,NULL,ctx) 
-                   || !EC_POINT_get_affine_coordinates(ecdsa->group,tmp_point,X,NULL,ctx))
+               if (!EC_POINT_mul(eckey->group, tmp_point, &k, NULL, NULL, ctx))
                {
-                       reason = ERR_R_EC_LIB;
+                       ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
+                       goto err;
+               }
+               if (EC_METHOD_get_field_type(EC_GROUP_method_of(eckey->group))
+                       == NID_X9_62_prime_field)
+               {
+                       if (!EC_POINT_get_affine_coordinates_GFp(eckey->group,
+                               tmp_point, X, NULL, ctx))
+                       {
+                               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
+                                       ERR_R_EC_LIB);
+                               goto err;
+                       }
+               }
+               else /* NID_X9_62_characteristic_two_field */
+               {
+                       if (!EC_POINT_get_affine_coordinates_GF2m(eckey->group,
+                               tmp_point, X, NULL, ctx))
+                       {
+                               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,
+                                       ERR_R_EC_LIB);
+                               goto err;
+                       }
+               }
+               if (!BN_nnmod(r,X,order,ctx))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
                        goto err;
                }
-               if (!BN_nnmod(r,X,order,ctx)) goto err;
        }
        while (BN_is_zero(r));
 
        /* compute the inverse of k */
-       if ((kinv = BN_mod_inverse(NULL,&k,order,ctx)) == NULL) goto err;
+       if ((kinv = BN_mod_inverse(NULL,&k,order,ctx)) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB);
+               goto err;       
+       }
 
        if (*rp == NULL)
                BN_clear_free(*rp);
@@ -202,7 +197,6 @@ static int ecdsa_sign_setup(ECDSA *ecdsa, BN_CTX *ctx_in, BIGNUM **kinvp, BIGNUM
 err:
        if (!ret)
        {
-               ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,reason);
                if (kinv != NULL) BN_clear_free(kinv);
                if (r != NULL) BN_clear_free(r);
        }
@@ -220,44 +214,60 @@ err:
 }
 
 
-static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, ECDSA *ecdsa)
+static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, 
+               EC_KEY *eckey)
 {
        BIGNUM *kinv=NULL,*r=NULL,*s=NULL,*m=NULL,*tmp=NULL,*order=NULL;
        BIGNUM xr;
        BN_CTX *ctx=NULL;
-       int reason=ERR_R_BN_LIB;
        ECDSA_SIG *ret=NULL;
+       ECDSA_DATA *ecdsa;
+
+       ecdsa = ecdsa_check(eckey);
 
-       if (!ecdsa || !ecdsa->group || !ecdsa->pub_key || !ecdsa->priv_key)
+       if (!eckey || !eckey->group || !eckey->pub_key || !eckey->priv_key 
+               || !ecdsa)
        {
-               reason = ECDSA_R_MISSING_PARAMETERS;
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER);
                goto err;
        }
        BN_init(&xr);
 
-       if ((ctx = BN_CTX_new()) == NULL) goto err;
-       if ((order = BN_new()) == NULL) goto err;
-       if ((tmp = BN_new()) == NULL) goto err;
-       if ((m = BN_new()) == NULL) goto err;
-       if ((s = BN_new()) == NULL) goto err;
+       if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL ||
+               (tmp = BN_new()) == NULL || (m = BN_new()) == NULL ||
+               (s = BN_new()) == NULL )
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
+               goto err;
+       }
 
-       if (!EC_GROUP_get_order(ecdsa->group,order,ctx))
+       if (!EC_GROUP_get_order(eckey->group,order,ctx))
        {
-               reason = ECDSA_R_ERR_EC_LIB;
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_EC_LIB);
                goto err;
        }
        if (dgst_len > BN_num_bytes(order))
        {
-               reason = ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE;
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,
+                       ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
                goto err;
        }
 
-       if (BN_bin2bn(dgst,dgst_len,m) == NULL) goto err;
+       if (BN_bin2bn(dgst,dgst_len,m) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
+               goto err;
+       }
        do
        {
-               if ((ecdsa->kinv == NULL) || (ecdsa->r == NULL))
+               if (ecdsa->kinv == NULL || ecdsa->r == NULL)
                {
-                       if (!ECDSA_sign_setup(ecdsa,ctx,&kinv,&r)) goto err;
+                       if (!ECDSA_sign_setup(eckey,ctx,&kinv,&r))
+                       {
+                               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,
+                                       ERR_R_ECDSA_LIB);
+                               goto err;
+                       }
                }
                else
                {
@@ -267,109 +277,176 @@ static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, ECDSA *
                        ecdsa->r = NULL;
                }
 
-               if (!BN_mod_mul(tmp,ecdsa->priv_key,r,order,ctx)) goto err;
-               if (!BN_add(s,tmp,m)) goto err;
+               if (!BN_mod_mul(tmp,eckey->priv_key,r,order,ctx))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
+                       goto err;
+               }
+               if (!BN_add(s,tmp,m))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
+                       goto err;
+               }
                if (BN_cmp(s,order) > 0)
                        BN_sub(s,s,order);
-               if (!BN_mod_mul(s,s,kinv,order,ctx)) goto err;
+               if (!BN_mod_mul(s,s,kinv,order,ctx))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
+                       goto err;
+               }
        }
        while (BN_is_zero(s));
 
        if ((ret = ECDSA_SIG_new()) == NULL)
        {
-               reason = ECDSA_R_SIGNATURE_MALLOC_FAILED;
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
                goto err;
        }
        if (BN_copy(ret->r, r) == NULL || BN_copy(ret->s, s) == NULL)
        {
                ECDSA_SIG_free(ret);
                ret = NULL;
-               reason = ERR_R_BN_LIB;
+               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB);
        }
        
 err:
-       if (!ret)
-               {
-               ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,reason);
-               }
-       if (r     != NULL) BN_clear_free(r);
-       if (s     != NULL) BN_clear_free(s);
-       if (ctx   != NULL) BN_CTX_free(ctx);
-       if (m     != NULL) BN_clear_free(m);
-       if (tmp   != NULL) BN_clear_free(tmp);
-       if (order != NULL) BN_clear_free(order);
-       if (kinv  != NULL) BN_clear_free(kinv);
+       if (r)
+               BN_clear_free(r);
+       if (s)
+               BN_clear_free(s);
+       if (ctx)
+               BN_CTX_free(ctx);
+       if (m)
+               BN_clear_free(m);
+       if (tmp)
+               BN_clear_free(tmp);
+       if (order)
+               BN_clear_free(order);
+       if (kinv)
+               BN_clear_free(kinv);
        return(ret);
 }
 
-static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, ECDSA_SIG *sig,
-                          ECDSA *ecdsa)
+static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len,
+               ECDSA_SIG *sig, EC_KEY *eckey)
 {
        BN_CTX *ctx;
        BIGNUM *order=NULL,*u1=NULL,*u2=NULL,*m=NULL,*X=NULL;
        EC_POINT *point=NULL;
-       int ret = -1,reason = ERR_R_BN_LIB;
-       if (!ecdsa || !ecdsa->group || !ecdsa->pub_key || !sig)
+       int ret = -1;
+       if (!eckey || !eckey->group || !eckey->pub_key || !sig)
        {
-               reason = ECDSA_R_MISSING_PARAMETERS;
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_MISSING_PARAMETERS);
                return -1;
        }
 
-       if ((ctx = BN_CTX_new()) == NULL) goto err;
-       if ((order = BN_new()) == NULL) goto err;
-       if ((u1 = BN_new()) == NULL) goto err;
-       if ((u2 = BN_new()) == NULL) goto err;
-       if ((m  = BN_new()) == NULL) goto err;
-       if ((X  = BN_new()) == NULL) goto err;
-       if (!EC_GROUP_get_order(ecdsa->group,order,ctx)) goto err;
+       if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL ||
+               (u1 = BN_new()) == NULL || (u2 = BN_new()) == NULL ||
+               (m  = BN_new()) == NULL || (X  = BN_new()) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE);
+               goto err;
+       }
+       if (!EC_GROUP_get_order(eckey->group, order, ctx))
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
+               goto err;
+       }
 
-       if (BN_is_zero(sig->r) || sig->r->neg || BN_ucmp(sig->r, order) >= 0)
+       if (BN_is_zero(sig->r) || BN_get_sign(sig->r) ||
+           BN_ucmp(sig->r, order) >= 0)
        {
-               reason = ECDSA_R_BAD_SIGNATURE;
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE);
                ret = 0;
                goto err;
        }
-       if (BN_is_zero(sig->s) || sig->s->neg || BN_ucmp(sig->s, order) >= 0)
+       if (BN_is_zero(sig->s) || BN_get_sign(sig->s) ||
+           BN_ucmp(sig->s, order) >= 0)
        {
-               reason = ECDSA_R_BAD_SIGNATURE;
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE);
                ret = 0;
                goto err;
        }
 
        /* calculate tmp1 = inv(S) mod order */
-       if ((BN_mod_inverse(u2,sig->s,order,ctx)) == NULL) goto err;
+       if ((BN_mod_inverse(u2,sig->s,order,ctx)) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
+               goto err;
+       }
        /* digest -> m */
-       if (BN_bin2bn(dgst,dgst_len,m) == NULL) goto err;
+       if (BN_bin2bn(dgst,dgst_len,m) == NULL)
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
+               goto err;
+       }
        /* u1 = m * tmp mod order */
-       if (!BN_mod_mul(u1,m,u2,order,ctx)) goto err;
+       if (!BN_mod_mul(u1,m,u2,order,ctx))
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
+               goto err;
+       }
        /* u2 = r * w mod q */
-       if (!BN_mod_mul(u2,sig->r,u2,order,ctx)) goto err;
+       if (!BN_mod_mul(u2,sig->r,u2,order,ctx))
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
+               goto err;
+       }
 
-       if ((point = EC_POINT_new(ecdsa->group)) == NULL)
+       if ((point = EC_POINT_new(eckey->group)) == NULL)
        {
-               reason = ERR_R_EC_LIB;
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE);
                goto err;
        }
-       if (!EC_POINT_mul(ecdsa->group,point,u1,ecdsa->pub_key,u2,ctx)
-           || !EC_POINT_get_affine_coordinates(ecdsa->group,point,X,NULL,ctx))
+       if (!EC_POINT_mul(eckey->group, point, u1, eckey->pub_key, u2, ctx))
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB);
+               goto err;
+       }
+       if (EC_METHOD_get_field_type(EC_GROUP_method_of(eckey->group))
+               == NID_X9_62_prime_field) 
+       {
+               if (!EC_POINT_get_affine_coordinates_GFp(eckey->group,
+                       point, X, NULL, ctx))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
+                       goto err;
+               }
+       }
+       else /* NID_X9_62_characteristic_two_field */
        {
-               reason = ERR_R_EC_LIB;
+               if (!EC_POINT_get_affine_coordinates_GF2m(eckey->group,
+                       point, X, NULL, ctx))
+               {
+                       ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB);
+                       goto err;
+               }
+       }
+       
+       if (!BN_nnmod(u1,X,order,ctx))
+       {
+               ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB);
                goto err;
        }
-       if (!BN_nnmod(u1,X,order,ctx)) goto err;
 
        /*  is now in u1.  If the signature is correct, it will be
         * equal to R. */
        ret = (BN_ucmp(u1,sig->r) == 0);
 
        err:
-       if (ret != 1) ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY,reason);
-       if (ctx != NULL) BN_CTX_free(ctx);
-       if (u1  != NULL) BN_clear_free(u1);
-       if (u2  != NULL) BN_clear_free(u2);
-       if (m   != NULL) BN_clear_free(m);
-       if (X   != NULL) BN_clear_free(X);
-       if (order != NULL) BN_clear_free(order);
-       if (point != NULL) EC_POINT_free(point);
+       if (ctx)
+               BN_CTX_free(ctx);
+       if (u1)
+               BN_clear_free(u1);
+       if (u2)
+               BN_clear_free(u2);
+       if (m)
+               BN_clear_free(m);
+       if (X)
+               BN_clear_free(X);
+       if (order)
+               BN_clear_free(order);
+       if (point)
+               EC_POINT_free(point);
        return(ret);
 }