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@Eminlin
Forked from SoulSu/aesecb.go
Created August 3, 2022 07:36
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golang aes ecb pKCS5Padding like java 3DES_ECB_PKCS5Padding
package idcardocr
import (
"bytes"
"crypto/cipher"
"crypto/des"
)
// 3DES加密
func ECB3DesEncrypt(content, key []byte) ([]byte, error) {
block, err := des.NewTripleDESCipher(key)
if err != nil {
return nil, err
}
ecb := NewECBEncrypter(block)
content = pKCS5Padding(content, block.BlockSize())
crypted := make([]byte, len(content))
ecb.CryptBlocks(crypted, content)
return crypted, nil
}
// 3DES解密
func ECB3DesDecrypt(crypted, key []byte) ([]byte, error) {
block, err := des.NewTripleDESCipher(key)
if err != nil {
return nil, err
}
blockMode := NewECBDecrypter(block)
origData := make([]byte, len([]byte(crypted)))
blockMode.CryptBlocks(origData, []byte(crypted))
origData = pKCS5UnPadding(origData)
return origData, nil
}
func pKCS5Padding(ciphertext []byte, blockSize int) []byte {
padding := blockSize - len(ciphertext)%blockSize
padtext := bytes.Repeat([]byte{byte(padding)}, padding)
return append(ciphertext, padtext...)
}
func pKCS5UnPadding(origData []byte) []byte {
length := len(origData)
// 去掉最后一个字节 unpadding 次
unpadding := int(origData[length-1])
return origData[:(length - unpadding)]
}
type ecb struct {
b cipher.Block
blockSize int
}
func newECB(b cipher.Block) *ecb {
return &ecb{
b: b,
blockSize: b.BlockSize(),
}
}
// 引入golang官方 https://codereview.appspot.com/7860047/
type ecbEncrypter ecb
// NewECBEncrypter returns a BlockMode which encrypts in electronic code book
// mode, using the given Block.
func NewECBEncrypter(b cipher.Block) cipher.BlockMode {
return (*ecbEncrypter)(newECB(b))
}
func (x *ecbEncrypter) BlockSize() int { return x.blockSize }
func (x *ecbEncrypter) CryptBlocks(dst, src []byte) {
if len(src)%x.blockSize != 0 {
panic("crypto/cipher: input not full blocks")
}
if len(dst) < len(src) {
panic("crypto/cipher: output smaller than input")
}
for len(src) > 0 {
x.b.Encrypt(dst, src[:x.blockSize])
src = src[x.blockSize:]
dst = dst[x.blockSize:]
}
}
type ecbDecrypter ecb
// NewECBDecrypter returns a BlockMode which decrypts in electronic code book
// mode, using the given Block.
func NewECBDecrypter(b cipher.Block) cipher.BlockMode {
return (*ecbDecrypter)(newECB(b))
}
func (x *ecbDecrypter) BlockSize() int { return x.blockSize }
func (x *ecbDecrypter) CryptBlocks(dst, src []byte) {
if len(src)%x.blockSize != 0 {
panic("crypto/cipher: input not full blocks")
}
if len(dst) < len(src) {
panic("crypto/cipher: output smaller than input")
}
for len(src) > 0 {
x.b.Decrypt(dst, src[:x.blockSize])
src = src[x.blockSize:]
dst = dst[x.blockSize:]
}
}
// end
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