utils_aes.go

package wxxx

import (
	"bytes"
	"crypto/aes"
	"crypto/cipher"
)

func PKCS7Padding(cipherText []byte, blockSize int) []byte {
	padding := blockSize - len(cipherText)%blockSize
	paddingText := bytes.Repeat([]byte{byte(padding)}, padding)
	return append(cipherText, paddingText...)
}

func PKCS7UnPadding(origData []byte) []byte {
	length := len(origData)
	unPadding := int(origData[length-1])
	return origData[:(length - unPadding)]
}

//noinspection ALL
func AESEcbDecrypt(data, key []byte) []byte {
	block, _ := aes.NewCipher(key)
	decrypted := make([]byte, len(data))
	size := block.BlockSize()
	for bs, be := 0, size; bs < len(data); bs, be = bs+size, be+size {
		block.Decrypt(decrypted[bs:be], data[bs:be])
	}
	return PKCS7UnPadding(decrypted)
}

func AESCbcDecrypt(data, key []byte) []byte {
	block, _ := aes.NewCipher(key)
	decrypted := make([]byte, len(data))
	iv := key
	mode := cipher.NewCBCDecrypter(block, iv)
	mode.CryptBlocks(decrypted, data)
	return PKCS7UnPadding(decrypted)
}

func AESEcbEncrypt(data, key []byte) []byte {
	block, _ := aes.NewCipher(key)
	data = PKCS7Padding(data, block.BlockSize())
	encrypted := make([]byte, len(data))
	size := block.BlockSize()
	for bs, be := 0, size; bs < len(data); bs, be = bs+size, be+size {
		block.Encrypt(encrypted[bs:be], data[bs:be])
	}
	return encrypted
}

func AESCbcEncrypt(data, key []byte) []byte {
	block, _ := aes.NewCipher(key)
	blockSize := block.BlockSize()
	data = PKCS7Padding(data, blockSize)
	encrypted := make([]byte, len(data))
	iv := key
	mode := cipher.NewCBCEncrypter(block, iv)
	mode.CryptBlocks(encrypted, data)
	//for bs, be := 0, size; bs < len(data); bs, be = bs+size, be+size {
	//	block.Encrypt(encrypted[bs:be], data[bs:be])
	//}
	return encrypted
}