github.com/TeaOSLab/EdgeNode@v1.3.8/internal/encrypt/method_aes_128_cfb.go (about)

     1  package encrypt
     2  
     3  import (
     4  	"bytes"
     5  	"crypto/aes"
     6  	"crypto/cipher"
     7  )
     8  
     9  type AES128CFBMethod struct {
    10  	iv    []byte
    11  	block cipher.Block
    12  }
    13  
    14  func (this *AES128CFBMethod) Init(key, iv []byte) error {
    15  	// 判断key是否为32长度
    16  	l := len(key)
    17  	if l > 16 {
    18  		key = key[:16]
    19  	} else if l < 16 {
    20  		key = append(key, bytes.Repeat([]byte{' '}, 16-l)...)
    21  	}
    22  
    23  	// 判断iv长度
    24  	l2 := len(iv)
    25  	if l2 > aes.BlockSize {
    26  		iv = iv[:aes.BlockSize]
    27  	} else if l2 < aes.BlockSize {
    28  		iv = append(iv, bytes.Repeat([]byte{' '}, aes.BlockSize-l2)...)
    29  	}
    30  
    31  	this.iv = iv
    32  
    33  	// block
    34  	block, err := aes.NewCipher(key)
    35  	if err != nil {
    36  		return err
    37  	}
    38  	this.block = block
    39  
    40  	return nil
    41  }
    42  
    43  func (this *AES128CFBMethod) Encrypt(src []byte) (dst []byte, err error) {
    44  	if len(src) == 0 {
    45  		return
    46  	}
    47  
    48  	defer func() {
    49  		err = RecoverMethodPanic(recover())
    50  	}()
    51  
    52  	dst = make([]byte, len(src))
    53  	encrypter := cipher.NewCFBEncrypter(this.block, this.iv)
    54  	encrypter.XORKeyStream(dst, src)
    55  
    56  	return
    57  }
    58  
    59  func (this *AES128CFBMethod) Decrypt(dst []byte) (src []byte, err error) {
    60  	if len(dst) == 0 {
    61  		return
    62  	}
    63  
    64  	defer func() {
    65  		err = RecoverMethodPanic(recover())
    66  	}()
    67  
    68  	src = make([]byte, len(dst))
    69  	encrypter := cipher.NewCFBDecrypter(this.block, this.iv)
    70  	encrypter.XORKeyStream(src, dst)
    71  
    72  	return
    73  }