github.com/insionng/yougam@v0.0.0-20170714101924-2bc18d833463/libraries/pingcap/tidb/util/auth.go (about)

     1  // Copyright 2015 PingCAP, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package util
    15  
    16  import (
    17  	"crypto/sha1"
    18  	"encoding/hex"
    19  
    20  	"github.com/insionng/yougam/libraries/juju/errors"
    21  )
    22  
    23  // CalcPassword is the algorithm convert hashed password to auth string.
    24  // See: https://dev.mysql.com/doc/internals/en/secure-password-authentication.html
    25  // SHA1( password ) XOR SHA1( "20-bytes random data from server" <concat> SHA1( SHA1( password ) ) )
    26  func CalcPassword(scramble, sha1pwd []byte) []byte {
    27  	if len(sha1pwd) == 0 {
    28  		return nil
    29  	}
    30  	// scrambleHash = SHA1(scramble + SHA1(sha1pwd))
    31  	// inner Hash
    32  	hash := Sha1Hash(sha1pwd)
    33  	// outer Hash
    34  	crypt := sha1.New()
    35  	crypt.Write(scramble)
    36  	crypt.Write(hash)
    37  	scramble = crypt.Sum(nil)
    38  	// token = scrambleHash XOR stage1Hash
    39  	for i := range scramble {
    40  		scramble[i] ^= sha1pwd[i]
    41  	}
    42  	return scramble
    43  }
    44  
    45  // Sha1Hash is an util function to calculate sha1 hash.
    46  func Sha1Hash(bs []byte) []byte {
    47  	crypt := sha1.New()
    48  	crypt.Write(bs)
    49  	return crypt.Sum(nil)
    50  }
    51  
    52  // EncodePassword converts plaintext password to hashed hex string.
    53  func EncodePassword(pwd string) string {
    54  	if len(pwd) == 0 {
    55  		return ""
    56  	}
    57  	hash := Sha1Hash([]byte(pwd))
    58  	return hex.EncodeToString(hash)
    59  }
    60  
    61  // DecodePassword converts hex string password to byte array.
    62  func DecodePassword(pwd string) ([]byte, error) {
    63  	x, err := hex.DecodeString(pwd)
    64  	if err != nil {
    65  		return nil, errors.Trace(err)
    66  	}
    67  	return x, nil
    68  }