C++ BN_CTX_end函數代碼示例

//.........這裏部分代碼省略.........
     */
    if (flen > num) {
        RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,
               RSA_R_DATA_GREATER_THAN_MOD_LEN);
        goto err;
    }

    /* make data into a big number */
    if (BN_bin2bn(from, (int)flen, f) == NULL)
        goto err;

    if (BN_ucmp(f, rsa->n) >= 0) {
        RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT,
               RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
        goto err;
    }

    if (!(rsa->flags & RSA_FLAG_NO_BLINDING)) {
        blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
        if (blinding == NULL) {
            RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
            goto err;
        }
    }

    if (blinding != NULL) {
        if (!local_blinding && ((unblind = BN_CTX_get(ctx)) == NULL)) {
            RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_MALLOC_FAILURE);
            goto err;
        }
        if (!rsa_blinding_convert(blinding, f, unblind, ctx))
            goto err;
    }

    /* do the decrypt */
    if ((rsa->flags & RSA_FLAG_EXT_PKEY) ||
        ((rsa->p != NULL) &&
         (rsa->q != NULL) &&
         (rsa->dmp1 != NULL) && (rsa->dmq1 != NULL) && (rsa->iqmp != NULL))) {
        if (!rsa->meth->rsa_mod_exp(ret, f, rsa, ctx))
            goto err;
    } else {
        BIGNUM local_d;
        BIGNUM *d = NULL;

        if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
            d = &local_d;
            BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
        } else
            d = rsa->d;

        if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
            if (!BN_MONT_CTX_set_locked
                (&rsa->_method_mod_n, CRYPTO_LOCK_RSA, rsa->n, ctx))
                goto err;
        if (!rsa->meth->bn_mod_exp(ret, f, d, rsa->n, ctx,
                                   rsa->_method_mod_n))
            goto err;
    }

    if (blinding)
        if (!rsa_blinding_invert(blinding, ret, unblind, ctx))
            goto err;

    p = buf;
    j = BN_bn2bin(ret, p);      /* j is only used with no-padding mode */

    switch (padding) {
    case RSA_PKCS1_PADDING:
        r = RSA_padding_check_PKCS1_type_2(to, num, buf, j, num);
        break;
# ifndef OPENSSL_NO_SHA
    case RSA_PKCS1_OAEP_PADDING:
        r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0);
        break;
# endif
    case RSA_SSLV23_PADDING:
        r = RSA_padding_check_SSLv23(to, num, buf, j, num);
        break;
    case RSA_NO_PADDING:
        r = RSA_padding_check_none(to, num, buf, j, num);
        break;
    default:
        RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
        goto err;
    }
    if (r < 0)
        RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, RSA_R_PADDING_CHECK_FAILED);

 err:
    if (ctx != NULL) {
        BN_CTX_end(ctx);
        BN_CTX_free(ctx);
    }
    if (buf != NULL) {
        OPENSSL_cleanse(buf, num);
        OPENSSL_free(buf);
    }
    return (r);
}

//.........這裏部分代碼省略.........
    }

    if (EC_POINT_is_at_infinity (group, b))
        return 1;

    if (a->Z_is_one && b->Z_is_one)
    {
        return ((BN_cmp (&a->X, &b->X) == 0) && BN_cmp (&a->Y, &b->Y) == 0) ? 0 : 1;
    }

    field_mul = group->meth->field_mul;
    field_sqr = group->meth->field_sqr;

    if (ctx == NULL)
    {
        ctx = new_ctx = BN_CTX_new ();
        if (ctx == NULL)
            return -1;
    }

    BN_CTX_start (ctx);
    tmp1 = BN_CTX_get (ctx);
    tmp2 = BN_CTX_get (ctx);
    Za23 = BN_CTX_get (ctx);
    Zb23 = BN_CTX_get (ctx);
    if (Zb23 == NULL)
        goto end;

    /* We have to decide whether
     *     (X_a/Z_a^2, Y_a/Z_a^3) = (X_b/Z_b^2, Y_b/Z_b^3),
     * or equivalently, whether
     *     (X_a*Z_b^2, Y_a*Z_b^3) = (X_b*Z_a^2, Y_b*Z_a^3).
     */

    if (!b->Z_is_one)
    {
        if (!field_sqr (group, Zb23, &b->Z, ctx))
            goto end;
        if (!field_mul (group, tmp1, &a->X, Zb23, ctx))
            goto end;
        tmp1_ = tmp1;
    }
    else
        tmp1_ = &a->X;
    if (!a->Z_is_one)
    {
        if (!field_sqr (group, Za23, &a->Z, ctx))
            goto end;
        if (!field_mul (group, tmp2, &b->X, Za23, ctx))
            goto end;
        tmp2_ = tmp2;
    }
    else
        tmp2_ = &b->X;

    /* compare  X_a*Z_b^2  with  X_b*Z_a^2 */
    if (BN_cmp (tmp1_, tmp2_) != 0)
    {
        ret = 1;                /* points differ */
        goto end;
    }


    if (!b->Z_is_one)
    {
        if (!field_mul (group, Zb23, Zb23, &b->Z, ctx))
            goto end;
        if (!field_mul (group, tmp1, &a->Y, Zb23, ctx))
            goto end;
        /* tmp1_ = tmp1 */
    }
    else
        tmp1_ = &a->Y;
    if (!a->Z_is_one)
    {
        if (!field_mul (group, Za23, Za23, &a->Z, ctx))
            goto end;
        if (!field_mul (group, tmp2, &b->Y, Za23, ctx))
            goto end;
        /* tmp2_ = tmp2 */
    }
    else
        tmp2_ = &b->Y;

    /* compare  Y_a*Z_b^3  with  Y_b*Z_a^3 */
    if (BN_cmp (tmp1_, tmp2_) != 0)
    {
        ret = 1;                /* points differ */
        goto end;
    }

    /* points are equal */
    ret = 0;

  end:
    BN_CTX_end (ctx);
    if (new_ctx != NULL)
        BN_CTX_free (new_ctx);
    return ret;
}

int ec_GFp_simple_group_set_curve (EC_GROUP * group, const BIGNUM * p, const BIGNUM * a, const BIGNUM * b, BN_CTX * ctx)
{
    int ret = 0;

    BN_CTX *new_ctx = NULL;

    BIGNUM *tmp_a;

    /* p must be a prime > 3 */
    if (BN_num_bits (p) <= 2 || !BN_is_odd (p))
    {
        ECerr (EC_F_EC_GFP_SIMPLE_GROUP_SET_CURVE, EC_R_INVALID_FIELD);
        return 0;
    }

    if (ctx == NULL)
    {
        ctx = new_ctx = BN_CTX_new ();
        if (ctx == NULL)
            return 0;
    }

    BN_CTX_start (ctx);
    tmp_a = BN_CTX_get (ctx);
    if (tmp_a == NULL)
        goto err;

    /* group->field */
    if (!BN_copy (&group->field, p))
        goto err;
    BN_set_negative (&group->field, 0);

    /* group->a */
    if (!BN_nnmod (tmp_a, a, p, ctx))
        goto err;
    if (group->meth->field_encode)
    {
        if (!group->meth->field_encode (group, &group->a, tmp_a, ctx))
            goto err;
    }
    else if (!BN_copy (&group->a, tmp_a))
        goto err;

    /* group->b */
    if (!BN_nnmod (&group->b, b, p, ctx))
        goto err;
    if (group->meth->field_encode)
        if (!group->meth->field_encode (group, &group->b, &group->b, ctx))
            goto err;

    /* group->a_is_minus3 */
    if (!BN_add_word (tmp_a, 3))
        goto err;
    group->a_is_minus3 = (0 == BN_cmp (tmp_a, &group->field));

    ret = 1;

  err:
    BN_CTX_end (ctx);
    if (new_ctx != NULL)
        BN_CTX_free (new_ctx);
    return ret;
}

//.........這裏部分代碼省略.........
 * avoiding conditional branches.
 */
static int 
ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, EC_POINT *r,
    const BIGNUM *scalar, const EC_POINT *point, BN_CTX *ctx)
{
	BIGNUM *x1, *x2, *z1, *z2;
	int ret = 0, i;
	BN_ULONG mask, word;

	if (r == point) {
		ECerr(EC_F_EC_GF2M_MONTGOMERY_POINT_MULTIPLY, EC_R_INVALID_ARGUMENT);
		return 0;
	}
	/* if result should be point at infinity */
	if ((scalar == NULL) || BN_is_zero(scalar) || (point == NULL) ||
	    EC_POINT_is_at_infinity(group, point) > 0) {
		return EC_POINT_set_to_infinity(group, r);
	}
	/* only support affine coordinates */
	if (!point->Z_is_one)
		return 0;

	/* Since point_multiply is static we can guarantee that ctx != NULL. */
	BN_CTX_start(ctx);
	if ((x1 = BN_CTX_get(ctx)) == NULL)
		goto err;
	if ((z1 = BN_CTX_get(ctx)) == NULL)
		goto err;

	x2 = &r->X;
	z2 = &r->Y;

	bn_wexpand(x1, group->field.top);
	bn_wexpand(z1, group->field.top);
	bn_wexpand(x2, group->field.top);
	bn_wexpand(z2, group->field.top);

	if (!BN_GF2m_mod_arr(x1, &point->X, group->poly))
		goto err;	/* x1 = x */
	if (!BN_one(z1))
		goto err;	/* z1 = 1 */
	if (!group->meth->field_sqr(group, z2, x1, ctx))
		goto err;	/* z2 = x1^2 = x^2 */
	if (!group->meth->field_sqr(group, x2, z2, ctx))
		goto err;
	if (!BN_GF2m_add(x2, x2, &group->b))
		goto err;	/* x2 = x^4 + b */

	/* find top most bit and go one past it */
	i = scalar->top - 1;
	mask = BN_TBIT;
	word = scalar->d[i];
	while (!(word & mask))
		mask >>= 1;
	mask >>= 1;
	/* if top most bit was at word break, go to next word */
	if (!mask) {
		i--;
		mask = BN_TBIT;
	}
	for (; i >= 0; i--) {
		word = scalar->d[i];
		while (mask) {
			BN_consttime_swap(word & mask, x1, x2, group->field.top);
			BN_consttime_swap(word & mask, z1, z2, group->field.top);
			if (!gf2m_Madd(group, &point->X, x2, z2, x1, z1, ctx))
				goto err;
			if (!gf2m_Mdouble(group, x1, z1, ctx))
				goto err;
			BN_consttime_swap(word & mask, x1, x2, group->field.top);
			BN_consttime_swap(word & mask, z1, z2, group->field.top);
			mask >>= 1;
		}
		mask = BN_TBIT;
	}

	/* convert out of "projective" coordinates */
	i = gf2m_Mxy(group, &point->X, &point->Y, x1, z1, x2, z2, ctx);
	if (i == 0)
		goto err;
	else if (i == 1) {
		if (!EC_POINT_set_to_infinity(group, r))
			goto err;
	} else {
		if (!BN_one(&r->Z))
			goto err;
		r->Z_is_one = 1;
	}

	/* GF(2^m) field elements should always have BIGNUM::neg = 0 */
	BN_set_negative(&r->X, 0);
	BN_set_negative(&r->Y, 0);

	ret = 1;

err:
	BN_CTX_end(ctx);
	return ret;
}

int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
	{
	int    r = 0;
	BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
	BN_CTX *ctx_new = NULL;

	/* compare the field types*/
	if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
	    EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
		return 1;
	/* compare the curve name (if present) */
	if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
	    EC_GROUP_get_curve_name(a) == EC_GROUP_get_curve_name(b))
		return 0;

	if (!ctx)
		ctx_new = ctx = BN_CTX_new();
	if (!ctx)
		return -1;
	
	BN_CTX_start(ctx);
	a1 = BN_CTX_get(ctx);
	a2 = BN_CTX_get(ctx);
	a3 = BN_CTX_get(ctx);
	b1 = BN_CTX_get(ctx);
	b2 = BN_CTX_get(ctx);
	b3 = BN_CTX_get(ctx);
	if (!b3)
		{
		BN_CTX_end(ctx);
		if (ctx_new)
			BN_CTX_free(ctx);
		return -1;
		}

	/* XXX This approach assumes that the external representation
	 * of curves over the same field type is the same.
	 */
	if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
	    !b->meth->group_get_curve(b, b1, b2, b3, ctx))
		r = 1;

	if (r || BN_cmp(a1, b1) || BN_cmp(a2, b2) || BN_cmp(a3, b3))
		r = 1;

	/* XXX EC_POINT_cmp() assumes that the methods are equal */
	if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
	    EC_GROUP_get0_generator(b), ctx))
		r = 1;

	if (!r)
		{
		/* compare the order and cofactor */
		if (!EC_GROUP_get_order(a, a1, ctx) ||
		    !EC_GROUP_get_order(b, b1, ctx) ||
		    !EC_GROUP_get_cofactor(a, a2, ctx) ||
		    !EC_GROUP_get_cofactor(b, b2, ctx))
			{
			BN_CTX_end(ctx);
			if (ctx_new)
				BN_CTX_free(ctx);
			return -1;
			}
		if (BN_cmp(a1, b1) || BN_cmp(a2, b2))
			r = 1;
		}

	BN_CTX_end(ctx);
	if (ctx_new)
		BN_CTX_free(ctx);

	return r;
	}

static int encrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
                   const uint8_t *in, size_t in_len, int padding) {
  const unsigned rsa_size = RSA_size(rsa);
  BIGNUM *f, *result;
  uint8_t *buf = NULL;
  BN_CTX *ctx = NULL;
  int i, ret = 0;

  if (rsa_size > OPENSSL_RSA_MAX_MODULUS_BITS) {
    OPENSSL_PUT_ERROR(RSA, RSA_R_MODULUS_TOO_LARGE);
    return 0;
  }

  if (max_out < rsa_size) {
    OPENSSL_PUT_ERROR(RSA, RSA_R_OUTPUT_BUFFER_TOO_SMALL);
    return 0;
  }

  if (BN_ucmp(rsa->n, rsa->e) <= 0) {
    OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_E_VALUE);
    return 0;
  }

  /* for large moduli, enforce exponent limit */
  if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS &&
      BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
    OPENSSL_PUT_ERROR(RSA, RSA_R_BAD_E_VALUE);
    return 0;
  }

  ctx = BN_CTX_new();
  if (ctx == NULL) {
    goto err;
  }

  BN_CTX_start(ctx);
  f = BN_CTX_get(ctx);
  result = BN_CTX_get(ctx);
  buf = OPENSSL_malloc(rsa_size);
  if (!f || !result || !buf) {
    OPENSSL_PUT_ERROR(RSA, ERR_R_MALLOC_FAILURE);
    goto err;
  }

  switch (padding) {
    case RSA_PKCS1_PADDING:
      i = RSA_padding_add_PKCS1_type_2(buf, rsa_size, in, in_len);
      break;
    case RSA_PKCS1_OAEP_PADDING:
      /* Use the default parameters: SHA-1 for both hashes and no label. */
      i = RSA_padding_add_PKCS1_OAEP_mgf1(buf, rsa_size, in, in_len,
                                          NULL, 0, NULL, NULL);
      break;
    case RSA_NO_PADDING:
      i = RSA_padding_add_none(buf, rsa_size, in, in_len);
      break;
    default:
      OPENSSL_PUT_ERROR(RSA, RSA_R_UNKNOWN_PADDING_TYPE);
      goto err;
  }

  if (i <= 0) {
    goto err;
  }

  if (BN_bin2bn(buf, rsa_size, f) == NULL) {
    goto err;
  }

  if (BN_ucmp(f, rsa->n) >= 0) {
    /* usually the padding functions would catch this */
    OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
    goto err;
  }

  if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
    if (BN_MONT_CTX_set_locked(&rsa->_method_mod_n, &rsa->lock, rsa->n, ctx) ==
        NULL) {
      goto err;
    }
  }

  if (!rsa->meth->bn_mod_exp(result, f, rsa->e, rsa->n, ctx,
                             rsa->_method_mod_n)) {
    goto err;
  }

  /* put in leading 0 bytes if the number is less than the length of the
   * modulus */
  if (!BN_bn2bin_padded(out, rsa_size, result)) {
    OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
    goto err;
  }

  *out_len = rsa_size;
  ret = 1;

err:
  if (ctx != NULL) {
    BN_CTX_end(ctx);
//.........這裏部分代碼省略.........

//.........這裏部分代碼省略.........
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
        return -1;
    }

    ctx = BN_CTX_new();
    if (ctx == NULL) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);
        return -1;
    }
    BN_CTX_start(ctx);
    u1 = BN_CTX_get(ctx);
    u2 = BN_CTX_get(ctx);
    m = BN_CTX_get(ctx);
    X = BN_CTX_get(ctx);
    if (X == NULL) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }

    order = EC_GROUP_get0_order(group);
    if (order == NULL) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
        goto err;
    }

    if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||
        BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) ||
        BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_BAD_SIGNATURE);
        ret = 0;                /* signature is invalid */
        goto err;
    }
    /* calculate tmp1 = inv(S) mod order */
    if (!BN_mod_inverse(u2, sig->s, order, ctx)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }
    /* digest -> m */
    i = BN_num_bits(order);
    /*
     * Need to truncate digest if it is too long: first truncate whole bytes.
     */
    if (8 * dgst_len > i)
        dgst_len = (i + 7) / 8;
    if (!BN_bin2bn(dgst, dgst_len, m)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }
    /* If still too long truncate remaining bits with a shift */
    if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }
    /* u1 = m * tmp mod order */
    if (!BN_mod_mul(u1, m, u2, order, ctx)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }
    /* u2 = r * w mod q */
    if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }

    if ((point = EC_POINT_new(group)) == NULL) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
        goto err;
    }
    if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==
        NID_X9_62_prime_field) {
        if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) {
            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
            goto err;
        }
    }
#ifndef OPENSSL_NO_EC2M
    else {                      /* NID_X9_62_characteristic_two_field */

        if (!EC_POINT_get_affine_coordinates_GF2m(group, point, X, NULL, ctx)) {
            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);
            goto err;
        }
    }
#endif
    if (!BN_nnmod(u1, X, order, ctx)) {
        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
        goto err;
    }
    /*  if the signature is correct u1 is equal to sig->r */
    ret = (BN_ucmp(u1, sig->r) == 0);
 err:
    BN_CTX_end(ctx);
    BN_CTX_free(ctx);
    EC_POINT_free(point);
    return ret;
}

BN_BLINDING *rsa_setup_blinding(RSA *rsa, BN_CTX *in_ctx) {
    BIGNUM local_n;
    BIGNUM *e, *n;
    BN_CTX *ctx;
    BN_BLINDING *ret = NULL;
    BN_MONT_CTX *mont_ctx = NULL;

    if (in_ctx == NULL) {
        ctx = BN_CTX_new();
        if (ctx == NULL) {
            return 0;
        }
    } else {
        ctx = in_ctx;
    }

    BN_CTX_start(ctx);
    e = BN_CTX_get(ctx);
    if (e == NULL) {
        OPENSSL_PUT_ERROR(RSA, rsa_setup_blinding, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    if (rsa->e == NULL) {
        e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
        if (e == NULL) {
            OPENSSL_PUT_ERROR(RSA, rsa_setup_blinding, RSA_R_NO_PUBLIC_EXPONENT);
            goto err;
        }
    } else {
        e = rsa->e;
    }

    n = &local_n;
    BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);

    if (rsa->flags & RSA_FLAG_CACHE_PUBLIC) {
        mont_ctx =
            BN_MONT_CTX_set_locked(&rsa->_method_mod_n, &rsa->lock, rsa->n, ctx);
        if (mont_ctx == NULL) {
            goto err;
        }
    }

    ret = BN_BLINDING_create_param(NULL, e, n, ctx, rsa->meth->bn_mod_exp,
                                   mont_ctx);
    if (ret == NULL) {
        OPENSSL_PUT_ERROR(RSA, rsa_setup_blinding, ERR_R_BN_LIB);
        goto err;
    }

err:
    BN_CTX_end(ctx);
    if (in_ctx == NULL) {
        BN_CTX_free(ctx);
    }
    if (rsa->e == NULL) {
        BN_free(e);
    }

    return ret;
}

int
dh_im_compute_key(PACE_CTX * ctx, const BUF_MEM * s, const BUF_MEM * in,
        BN_CTX *bn_ctx)
{
    int ret = 0;
    BUF_MEM * x_mem = NULL;
    BIGNUM * x_bn = NULL, *a = NULL, *p_1 = NULL, *q = NULL;
    DH *static_key = NULL, *ephemeral_key = NULL;

    check((ctx && in && ctx->ka_ctx), "Invalid arguments");
    if (in->length < (size_t) EVP_CIPHER_key_length(ctx->ka_ctx->cipher)
            || !ctx->static_key)
        goto err;

    BN_CTX_start(bn_ctx);

    static_key = EVP_PKEY_get1_DH(ctx->static_key);
    if (!static_key)
        goto err;

    /* Initialize ephemeral parameters with parameters from the static key */
    ephemeral_key = DHparams_dup_with_q(static_key);
    if (!ephemeral_key)
        goto err;

    /* Perform the actual mapping */
    x_mem = cipher_no_pad(ctx->ka_ctx, NULL, in, s, 1);
    if (!x_mem)
        goto err;
    x_bn = BN_bin2bn((unsigned char *) x_mem->data, x_mem->length, x_bn);
    a = BN_CTX_get(bn_ctx);
    q = DH_get_q(static_key, bn_ctx);
    p_1 = BN_dup(static_key->p);
    if (!x_bn || !a || !q || !p_1 ||
            /* p_1 = p-1 */
            !BN_sub_word(p_1, 1) ||
            /* a = p-1 / q */
            !BN_div(a, NULL, p_1, q, bn_ctx) ||
            /* g~ = x^a mod p */
            !BN_mod_exp(ephemeral_key->g, x_bn, a, static_key->p, bn_ctx))
        goto err;

    /* check if g~ != 1 */
    check((!BN_is_one(ephemeral_key->g)), "Bad DH generator");

    /* Copy ephemeral key to context structure */
    if (!EVP_PKEY_set1_DH(ctx->ka_ctx->key, ephemeral_key))
        goto err;

    ret = 1;

err:
    if (q)
        BN_clear_free(q);
    if (p_1)
        BN_clear_free(p_1);
    if (x_bn)
        BN_clear_free(x_bn);
    if (x_mem)
        BUF_MEM_free(x_mem);
    /* Decrement reference count, keys are still available via PACE_CTX */
    if (static_key)
        DH_free(static_key);
    if (ephemeral_key)
        DH_free(ephemeral_key);
    BN_CTX_end(bn_ctx);

    return ret;
}

/* Actually there is no reason to insist that 'generator' be a generator.
 * It's just as OK (and in some sense better) to use a generator of the
 * order-q subgroup.
 */
DH *DH_generate_parameters(int prime_len, int generator,
	     void (*callback)(int,int,void *), void *cb_arg)
	{
	BIGNUM *p=NULL,*t1,*t2;
	DH *ret=NULL;
	int g,ok= -1;
	BN_CTX *ctx=NULL;

	ret=DH_new();
	if (ret == NULL) goto err;
	ctx=BN_CTX_new();
	if (ctx == NULL) goto err;
	BN_CTX_start(ctx);
	t1 = BN_CTX_get(ctx);
	t2 = BN_CTX_get(ctx);
	if (t1 == NULL || t2 == NULL) goto err;
	
	if (generator <= 1)
		goto err;

	if (generator == DH_GENERATOR_2)
		{
		if (!BN_set_word(t1,24)) goto err;
		if (!BN_set_word(t2,11)) goto err;
		g=2;
		}
	else if (generator == DH_GENERATOR_5)
		{
		if (!BN_set_word(t1,10)) goto err;
		if (!BN_set_word(t2,3)) goto err;
		/* BN_set_word(t3,7); just have to miss
		 * out on these ones :-( */
		g=5;
		}
	else
		{
		/* in the general case, don't worry if 'generator' is a
		 * generator or not: since we are using safe primes,
		 * it will generate either an order-q or an order-2q group,
		 * which both is OK */
		if (!BN_set_word(t1,2)) goto err;
		if (!BN_set_word(t2,1)) goto err;
		g=generator;
		}
	
	p=BN_generate_prime(NULL,prime_len,1,t1,t2,callback,cb_arg);
	if (p == NULL) goto err;
	if (callback != NULL) callback(3,0,cb_arg);
	ret->p=p;
	ret->g=BN_new();
	if (!BN_set_word(ret->g,g)) goto err;
	ok=1;
err:
	if (ok == -1)
		ok=0;

	if (ctx != NULL)
		{
		BN_CTX_end(ctx);
		BN_CTX_free(ctx);
		}
	if (!ok && (ret != NULL))
		{
		DH_free(ret);
		ret=NULL;
		}
	return(ret);
	}

//.........這裏部分代碼省略.........
  multiple = BN_CTX_get(ctx);
  p_plus_q = BN_CTX_get(ctx);
  p_minus_q = BN_CTX_get(ctx);

  if (totient == NULL || rem == NULL || multiple == NULL || p_plus_q == NULL ||
      p_minus_q == NULL) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, ERR_R_MALLOC_FAILURE);
    goto err;
  }

  /* ed-1 is a small multiple of φ(n). */
  if (!BN_mul(totient, rsa->e, rsa->d, ctx) ||
      !BN_sub_word(totient, 1) ||
      /* φ(n) =
       * pq - p - q + 1 =
       * n - (p + q) + 1
       *
       * Thus n is a reasonable estimate for φ(n). So, (ed-1)/n will be very
       * close. But, when we calculate the quotient, we'll be truncating it
       * because we discard the remainder. Thus (ed-1)/multiple will be >= n,
       * which the totient cannot be. So we add one to the estimate.
       *
       * Consider ed-1 as:
       *
       * multiple * (n - (p+q) + 1) =
       * multiple*n - multiple*(p+q) + multiple
       *
       * When we divide by n, the first term becomes multiple and, since
       * multiple and p+q is tiny compared to n, the second and third terms can
       * be ignored. Thus I claim that subtracting one from the estimate is
       * sufficient. */
      !BN_div(multiple, NULL, totient, rsa->n, ctx) ||
      !BN_add_word(multiple, 1) ||
      !BN_div(totient, rem, totient, multiple, ctx)) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, ERR_R_BN_LIB);
    goto err;
  }

  if (!BN_is_zero(rem)) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, RSA_R_BAD_RSA_PARAMETERS);
    goto err;
  }

  rsa->p = BN_new();
  rsa->q = BN_new();
  rsa->dmp1 = BN_new();
  rsa->dmq1 = BN_new();
  rsa->iqmp = BN_new();
  if (rsa->p == NULL || rsa->q == NULL || rsa->dmp1 == NULL || rsa->dmq1 ==
      NULL || rsa->iqmp == NULL) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, ERR_R_MALLOC_FAILURE);
    goto err;
  }

  /* φ(n) = n - (p + q) + 1 =>
   * n - totient + 1 = p + q */
  if (!BN_sub(p_plus_q, rsa->n, totient) ||
      !BN_add_word(p_plus_q, 1) ||
      /* p - q = sqrt((p+q)^2 - 4n) */
      !BN_sqr(rem, p_plus_q, ctx) ||
      !BN_lshift(multiple, rsa->n, 2) ||
      !BN_sub(rem, rem, multiple) ||
      !BN_sqrt(p_minus_q, rem, ctx) ||
      /* q is 1/2 (p+q)-(p-q) */
      !BN_sub(rsa->q, p_plus_q, p_minus_q) ||
      !BN_rshift1(rsa->q, rsa->q) ||
      !BN_div(rsa->p, NULL, rsa->n, rsa->q, ctx) ||
      !BN_mul(multiple, rsa->p, rsa->q, ctx)) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, ERR_R_BN_LIB);
    goto err;
  }

  if (BN_cmp(multiple, rsa->n) != 0) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, RSA_R_INTERNAL_ERROR);
    goto err;
  }

  if (!BN_sub(rem, rsa->p, BN_value_one()) ||
      !BN_mod(rsa->dmp1, rsa->d, rem, ctx) ||
      !BN_sub(rem, rsa->q, BN_value_one()) ||
      !BN_mod(rsa->dmq1, rsa->d, rem, ctx) ||
      !BN_mod_inverse(rsa->iqmp, rsa->q, rsa->p, ctx)) {
    OPENSSL_PUT_ERROR(RSA, RSA_recover_crt_params, ERR_R_BN_LIB);
    goto err;
  }

  ok = 1;

err:
  BN_CTX_end(ctx);
  BN_CTX_free(ctx);
  if (!ok) {
    bn_free_and_null(&rsa->p);
    bn_free_and_null(&rsa->q);
    bn_free_and_null(&rsa->dmp1);
    bn_free_and_null(&rsa->dmq1);
    bn_free_and_null(&rsa->iqmp);
  }
  return ok;
}

BN_BLINDING *RSA_setup_blinding(RSA *rsa, BN_CTX *in_ctx)
{
    BIGNUM local_n;
    BIGNUM *e,*n;
    BN_CTX *ctx;
    BN_BLINDING *ret = NULL;

    if (in_ctx == NULL)
    {
        if ((ctx = BN_CTX_new()) == NULL) return 0;
    }
    else
        ctx = in_ctx;

    BN_CTX_start(ctx);
    e  = BN_CTX_get(ctx);
    if (e == NULL)
    {
        RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    if (rsa->e == NULL)
    {
        e = rsa_get_public_exp(rsa->d, rsa->p, rsa->q, ctx);
        if (e == NULL)
        {
            RSAerr(RSA_F_RSA_SETUP_BLINDING, RSA_R_NO_PUBLIC_EXPONENT);
            goto err;
        }
    }
    else
        e = rsa->e;


    if ((RAND_status() == 0) && rsa->d != NULL && rsa->d->d != NULL)
    {
        /* if PRNG is not properly seeded, resort to secret
         * exponent as unpredictable seed */
        RAND_add(rsa->d->d, rsa->d->dmax * sizeof rsa->d->d[0], 0.0);
    }

    if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME))
    {
        /* Set BN_FLG_CONSTTIME flag */
        n = &local_n;
        BN_with_flags(n, rsa->n, BN_FLG_CONSTTIME);
    }
    else
        n = rsa->n;

    ret = BN_BLINDING_create_param(NULL, e, n, ctx,
                                   rsa->meth->bn_mod_exp, rsa->_method_mod_n);
    if (ret == NULL)
    {
        RSAerr(RSA_F_RSA_SETUP_BLINDING, ERR_R_BN_LIB);
        goto err;
    }
    CRYPTO_THREADID_current(BN_BLINDING_thread_id(ret));
err:
    BN_CTX_end(ctx);
    if (in_ctx == NULL)
        BN_CTX_free(ctx);
    if(rsa->e == NULL)
        BN_free(e);

    return ret;
}

//.........這裏部分代碼省略.........

    /* compute I mod p */
    if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
        c = &local_c;
        BN_with_flags(c, I, BN_FLG_CONSTTIME);
        if (!BN_mod(r1, c, rsa->p, ctx))
            goto err;
    } else {
        if (!BN_mod(r1, I, rsa->p, ctx))
            goto err;
    }

    /* compute r1^dmp1 mod p */
    if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
        dmp1 = &local_dmp1;
        BN_with_flags(dmp1, rsa->dmp1, BN_FLG_CONSTTIME);
    } else
        dmp1 = rsa->dmp1;
    if (!rsa->meth->bn_mod_exp(r0, r1, dmp1, rsa->p, ctx, rsa->_method_mod_p))
        goto err;

    if (!BN_sub(r0, r0, m1))
        goto err;
    /*
     * This will help stop the size of r0 increasing, which does affect the
     * multiply if it optimised for a power of 2 size
     */
    if (BN_is_negative(r0))
        if (!BN_add(r0, r0, rsa->p))
            goto err;

    if (!BN_mul(r1, r0, rsa->iqmp, ctx))
        goto err;

    /* Turn BN_FLG_CONSTTIME flag on before division operation */
    if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
        pr1 = &local_r1;
        BN_with_flags(pr1, r1, BN_FLG_CONSTTIME);
    } else
        pr1 = r1;
    if (!BN_mod(r0, pr1, rsa->p, ctx))
        goto err;

    /*
     * If p < q it is occasionally possible for the correction of adding 'p'
     * if r0 is negative above to leave the result still negative. This can
     * break the private key operations: the following second correction
     * should *always* correct this rare occurrence. This will *never* happen
     * with OpenSSL generated keys because they ensure p > q [steve]
     */
    if (BN_is_negative(r0))
        if (!BN_add(r0, r0, rsa->p))
            goto err;
    if (!BN_mul(r1, r0, rsa->q, ctx))
        goto err;
    if (!BN_add(r0, r1, m1))
        goto err;

    if (rsa->e && rsa->n) {
        if (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx,
                                   rsa->_method_mod_n))
            goto err;
        /*
         * If 'I' was greater than (or equal to) rsa->n, the operation will
         * be equivalent to using 'I mod n'. However, the result of the
         * verify will *always* be less than 'n' so we don't check for
         * absolute equality, just congruency.
         */
        if (!BN_sub(vrfy, vrfy, I))
            goto err;
        if (!BN_mod(vrfy, vrfy, rsa->n, ctx))
            goto err;
        if (BN_is_negative(vrfy))
            if (!BN_add(vrfy, vrfy, rsa->n))
                goto err;
        if (!BN_is_zero(vrfy)) {
            /*
             * 'I' and 'vrfy' aren't congruent mod n. Don't leak
             * miscalculated CRT output, just do a raw (slower) mod_exp and
             * return that instead.
             */

            BIGNUM local_d;
            BIGNUM *d = NULL;

            if (!(rsa->flags & RSA_FLAG_NO_CONSTTIME)) {
                d = &local_d;
                BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
            } else
                d = rsa->d;
            if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx,
                                       rsa->_method_mod_n))
                goto err;
        }
    }
    ret = 1;
 err:
    BN_CTX_end(ctx);
    return (ret);
}

/* signature verification */
static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
                                  unsigned char *to, RSA *rsa, int padding)
{
    BIGNUM *f, *ret;
    int i, num = 0, r = -1;
    unsigned char *p;
    unsigned char *buf = NULL;
    BN_CTX *ctx = NULL;

    if (BN_num_bits(rsa->n) > OPENSSL_RSA_MAX_MODULUS_BITS) {
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_MODULUS_TOO_LARGE);
        return -1;
    }

    if (BN_ucmp(rsa->n, rsa->e) <= 0) {
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
        return -1;
    }

    /* for large moduli, enforce exponent limit */
    if (BN_num_bits(rsa->n) > OPENSSL_RSA_SMALL_MODULUS_BITS) {
        if (BN_num_bits(rsa->e) > OPENSSL_RSA_MAX_PUBEXP_BITS) {
            RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_BAD_E_VALUE);
            return -1;
        }
    }

    if ((ctx = BN_CTX_new()) == NULL)
        goto err;
    BN_CTX_start(ctx);
    f = BN_CTX_get(ctx);
    ret = BN_CTX_get(ctx);
    num = BN_num_bytes(rsa->n);
    buf = OPENSSL_malloc(num);
    if (!f || !ret || !buf) {
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    /*
     * This check was for equality but PGP does evil things and chops off the
     * top '0' bytes
     */
    if (flen > num) {
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_DATA_GREATER_THAN_MOD_LEN);
        goto err;
    }

    if (BN_bin2bn(from, flen, f) == NULL)
        goto err;

    if (BN_ucmp(f, rsa->n) >= 0) {
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT,
               RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
        goto err;
    }

    if (rsa->flags & RSA_FLAG_CACHE_PUBLIC)
        if (!BN_MONT_CTX_set_locked
            (&rsa->_method_mod_n, CRYPTO_LOCK_RSA, rsa->n, ctx))
            goto err;

    if (!rsa->meth->bn_mod_exp(ret, f, rsa->e, rsa->n, ctx,
                               rsa->_method_mod_n))
        goto err;

    if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
        if (!BN_sub(ret, rsa->n, ret))
            goto err;

    p = buf;
    i = BN_bn2bin(ret, p);

    switch (padding) {
    case RSA_PKCS1_PADDING:
        r = RSA_padding_check_PKCS1_type_1(to, num, buf, i, num);
        break;
    case RSA_X931_PADDING:
        r = RSA_padding_check_X931(to, num, buf, i, num);
        break;
    case RSA_NO_PADDING:
        r = RSA_padding_check_none(to, num, buf, i, num);
        break;
    default:
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_UNKNOWN_PADDING_TYPE);
        goto err;
    }
    if (r < 0)
        RSAerr(RSA_F_RSA_EAY_PUBLIC_DECRYPT, RSA_R_PADDING_CHECK_FAILED);

 err:
    if (ctx != NULL) {
        BN_CTX_end(ctx);
        BN_CTX_free(ctx);
    }
    if (buf != NULL) {
        OPENSSL_cleanse(buf, num);
        OPENSSL_free(buf);
    }
//.........這裏部分代碼省略.........

//.........這裏部分代碼省略.........

  if (!BN_mod(r0, pr1, rsa->p, ctx)) {
    goto err;
  }

  /* If p < q it is occasionally possible for the correction of
   * adding 'p' if r0 is negative above to leave the result still
   * negative. This can break the private key operations: the following
   * second correction should *always* correct this rare occurrence.
   * This will *never* happen with OpenSSL generated keys because
   * they ensure p > q [steve] */
  if (BN_is_negative(r0)) {
    if (!BN_add(r0, r0, rsa->p)) {
      goto err;
    }
  }
  if (!BN_mul(r1, r0, rsa->q, ctx)) {
    goto err;
  }
  if (!BN_add(r0, r1, m1)) {
    goto err;
  }

  for (i = 0; i < num_additional_primes; i++) {
    /* multi-prime RSA. */
    BIGNUM local_exp, local_prime;
    BIGNUM *exp = &local_exp, *prime = &local_prime;
    RSA_additional_prime *ap =
        sk_RSA_additional_prime_value(rsa->additional_primes, i);

    BN_with_flags(exp, ap->exp, BN_FLG_CONSTTIME);
    BN_with_flags(prime, ap->prime, BN_FLG_CONSTTIME);

    /* c will already point to a BIGNUM with the correct flags. */
    if (!BN_mod(r1, c, prime, ctx)) {
      goto err;
    }

    if ((rsa->flags & RSA_FLAG_CACHE_PRIVATE) &&
        !BN_MONT_CTX_set_locked(&ap->method_mod, &rsa->lock, prime, ctx)) {
      goto err;
    }

    if (!rsa->meth->bn_mod_exp(m1, r1, exp, prime, ctx, ap->method_mod)) {
      goto err;
    }

    BN_set_flags(m1, BN_FLG_CONSTTIME);

    if (!BN_sub(m1, m1, r0) ||
        !BN_mul(m1, m1, ap->coeff, ctx) ||
        !BN_mod(m1, m1, prime, ctx) ||
        (BN_is_negative(m1) && !BN_add(m1, m1, prime)) ||
        !BN_mul(m1, m1, ap->r, ctx) ||
        !BN_add(r0, r0, m1)) {
      goto err;
    }
  }

  if (rsa->e && rsa->n) {
    if (!rsa->meth->bn_mod_exp(vrfy, r0, rsa->e, rsa->n, ctx,
                               rsa->_method_mod_n)) {
      goto err;
    }
    /* If 'I' was greater than (or equal to) rsa->n, the operation
     * will be equivalent to using 'I mod n'. However, the result of
     * the verify will *always* be less than 'n' so we don't check
     * for absolute equality, just congruency. */
    if (!BN_sub(vrfy, vrfy, I)) {
      goto err;
    }
    if (!BN_mod(vrfy, vrfy, rsa->n, ctx)) {
      goto err;
    }
    if (BN_is_negative(vrfy)) {
      if (!BN_add(vrfy, vrfy, rsa->n)) {
        goto err;
      }
    }
    if (!BN_is_zero(vrfy)) {
      /* 'I' and 'vrfy' aren't congruent mod n. Don't leak
       * miscalculated CRT output, just do a raw (slower)
       * mod_exp and return that instead. */

      BIGNUM local_d;
      BIGNUM *d = NULL;

      d = &local_d;
      BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);
      if (!rsa->meth->bn_mod_exp(r0, I, d, rsa->n, ctx, rsa->_method_mod_n)) {
        goto err;
      }
    }
  }
  ret = 1;

err:
  BN_CTX_end(ctx);
  return ret;
}