if err != nil {
		return nil, err
	}

	if boring.Enabled {
		bkey, err := boringPrivateKey(priv)
		if err != nil {
			return nil, err
		}
		// Note: BoringCrypto always does decrypt "withCheck".
		// (It's not just decrypt.)
		s, err := boring.DecryptRSANoPadding(bkey, em)
		if err != nil {
			return nil, err
		}
		return s, nil
	}

// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build boringcrypto

package tls

import (
	"crypto/ecdsa"
	"crypto/elliptic"
	"crypto/internal/boring/fipstls"
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"crypto/x509/pkix"
	"encoding/pem"
	"fmt"
	"internal/obscuretestdata"
	"math/big"
	"net"
	"runtime"

		return cipher.NewCBCDecrypter(block, iv)
	}
	return cipher.NewCBCEncrypter(block, iv)
}

// macSHA1 returns a SHA-1 based constant time MAC.
func macSHA1(key []byte) hash.Hash {
	h := sha1.New
	// The BoringCrypto SHA1 does not have a constant-time
	// checksum function, so don't try to use it.
	if !boring.Enabled {
		h = newConstantTimeHash(h)
	}
	return hmac.New(h, key)
}