github.com/adnan-c/fabric_e2e_couchdb@v0.6.1-preview.0.20170228180935-21ce6b23cf91/accesscontrol/crypto/utils/keys.go (about)

     1  /*
     2  Copyright IBM Corp. 2016 All Rights Reserved.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8  		 http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package utils
    18  
    19  import (
    20  	"crypto/rand"
    21  	"crypto/x509"
    22  	"encoding/pem"
    23  	"errors"
    24  	"fmt"
    25  )
    26  
    27  // PEMtoAES extracts from the PEM an AES key
    28  func PEMtoAES(raw []byte, pwd []byte) ([]byte, error) {
    29  	if len(raw) == 0 {
    30  		return nil, errors.New("Invalid PEM. It must be different from nil")
    31  	}
    32  	block, _ := pem.Decode(raw)
    33  	if block == nil {
    34  		return nil, fmt.Errorf("Failed decoding [% x]", raw)
    35  	}
    36  
    37  	if x509.IsEncryptedPEMBlock(block) {
    38  		if len(pwd) == 0 {
    39  			return nil, errors.New("Encrypted Key. Need a password!!!")
    40  		}
    41  
    42  		decrypted, err := x509.DecryptPEMBlock(block, pwd)
    43  		if err != nil {
    44  			return nil, err
    45  		}
    46  		return decrypted, nil
    47  	}
    48  
    49  	return block.Bytes, nil
    50  }
    51  
    52  // AEStoPEM encapsulates an AES key in the PEM format
    53  func AEStoPEM(raw []byte) []byte {
    54  	return pem.EncodeToMemory(&pem.Block{Type: "AES PRIVATE KEY", Bytes: raw})
    55  }
    56  
    57  // AEStoEncryptedPEM encapsulates an AES key in the encrypted PEM format
    58  func AEStoEncryptedPEM(raw []byte, pwd []byte) ([]byte, error) {
    59  	if len(raw) == 0 {
    60  		return nil, errors.New("Invalid key. It must be different from nil")
    61  	}
    62  	if len(pwd) == 0 {
    63  		return AEStoPEM(raw), nil
    64  	}
    65  
    66  	block, err := x509.EncryptPEMBlock(
    67  		rand.Reader,
    68  		"AES PRIVATE KEY",
    69  		raw,
    70  		pwd,
    71  		x509.PEMCipherAES256)
    72  
    73  	if err != nil {
    74  		return nil, err
    75  	}
    76  
    77  	return pem.EncodeToMemory(block), nil
    78  }