Address pull request comments

* Use crypto.Sign instead of directly calling secp256k1 lib
* Rename UserAccount to Account and Addr to Address (for consistency)
* Change AccountManager.Sign to take ptr to Account instead of
  address byte array
* Simplify copying of Accounts in Accounts()
* PubkeyToAddress and GetEntropyCSPRNG now exported

3 files changed, 7 insertions, 8 deletions

diff --git a/crypto/crypto.go b/crypto/crypto.go
index f8d6139a8..effa703d0 100644
--- a/crypto/crypto.go
+++ b/crypto/crypto.go
@@ -133,8 +133,7 @@ func ImportPreSaleKey(keyStore KeyStore2, keyJSON []byte, password string) (*Key
 	if err != nil {
 		return nil, err
 	}
-	id := uuid.NewRandom()
-	key.Id = id
+	key.Id = uuid.NewRandom()
 	err = keyStore.StoreKey(key, password)
 	return key, err
 }
@@ -167,7 +166,7 @@ func decryptPreSaleKey(fileContent []byte, password string) (key *Key, err error
 	ecKey := ToECDSA(ethPriv)
 	key = &Key{
 		Id:         nil,
-		Address:    pubkeyToAddress(ecKey.PublicKey),
+		Address:    PubkeyToAddress(ecKey.PublicKey),
 		PrivateKey: ecKey,
 	}
 	derivedAddr := ethutil.Bytes2Hex(key.Address)
@@ -225,7 +224,7 @@ func PKCS7Unpad(in []byte) []byte {
 	return in[:len(in)-int(padding)]
 }
 
-func pubkeyToAddress(p ecdsa.PublicKey) []byte {
+func PubkeyToAddress(p ecdsa.PublicKey) []byte {
 	pubBytes := FromECDSAPub(&p)
 	return Sha3(pubBytes[1:])[12:]
 }
diff --git a/crypto/key.go b/crypto/key.go
index f8f64c35c..b9ad34f47 100644
--- a/crypto/key.go
+++ b/crypto/key.go
@@ -102,7 +102,7 @@ func NewKey(rand io.Reader) *Key {
 	id := uuid.NewRandom()
 	key := &Key{
 		Id:         id,
-		Address:    pubkeyToAddress(privateKeyECDSA.PublicKey),
+		Address:    PubkeyToAddress(privateKeyECDSA.PublicKey),
 		PrivateKey: privateKeyECDSA,
 	}
 	return key
diff --git a/crypto/key_store_passphrase.go b/crypto/key_store_passphrase.go
index 807a91397..0862b7886 100644
--- a/crypto/key_store_passphrase.go
+++ b/crypto/key_store_passphrase.go
@@ -116,7 +116,7 @@ func (ks keyStorePassphrase) GetKeyAddresses() (addresses [][]byte, err error) {
 
 func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
 	authArray := []byte(auth)
-	salt := getEntropyCSPRNG(32)
+	salt := GetEntropyCSPRNG(32)
 	derivedKey, err := scrypt.Key(authArray, salt, scryptN, scryptr, scryptp, scryptdkLen)
 	if err != nil {
 		return err
@@ -131,7 +131,7 @@ func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
 		return err
 	}
 
-	iv := getEntropyCSPRNG(aes.BlockSize) // 16
+	iv := GetEntropyCSPRNG(aes.BlockSize) // 16
 	AES256CBCEncrypter := cipher.NewCBCEncrypter(AES256Block, iv)
 	cipherText := make([]byte, len(toEncrypt))
 	AES256CBCEncrypter.CryptBlocks(cipherText, toEncrypt)
@@ -197,7 +197,7 @@ func DecryptKey(ks keyStorePassphrase, keyAddr []byte, auth string) (keyBytes []
 	return keyBytes, keyId, err
 }
 
-func getEntropyCSPRNG(n int) []byte {
+func GetEntropyCSPRNG(n int) []byte {
 	mainBuff := make([]byte, n)
 	_, err := io.ReadFull(crand.Reader, mainBuff)
 	if err != nil {