关于AES更多的知识，请自行脑补，密码学中的高级加密标准（Advanced Encryption Standard，AES），又称Rijndael加密法，是经常采用的一种区块加密标准。
在golang的标准库aes可以实现AES加密，官方标准库aes文档链接：http://pkg.go.dev/crypto/aes
本篇分享出在实际工作中的实际需求，需求很简单，就是需要实现一个命令行应用程序，可以对传入的明文字符串进行加密，传入密文进行解密。命令行应用叫做passctl，并带有帮助功能。实现命令行应用程序有很多强大的第三方库，因为需求过于简单，那么本篇就用标准库中os即可。
package main
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"encoding/base64"
"fmt"
)
var EncKey = []byte("QAZWSXEDCRFVTGBY") // 16位密码串
func pkcs7Padding(data []byte, blockSize int) []byte {
padding := blockSize - len(data)%blockSize
padText := bytes.Repeat([]byte{byte(padding)}, padding)
return append(data, padText...)
}
func AesEncrypt(data []byte, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
blockSize := block.BlockSize()
encryptBytes := pkcs7Padding(data, blockSize)
crypted := make([]byte, len(encryptBytes))
blockMode := cipher.NewCBCEncrypter(block, key[:blockSize])
blockMode.CryptBlocks(crypted, encryptBytes)
return crypted, nil
}
func EncryptByAes(data []byte) (string, error) {
res, err := AesEncrypt(data, EncKey)
if err != nil {
return "", err
}
return base64.StdEncoding.EncodeToString(res), nil
}
func main() {
plaintext := "2wsx$RFV!Qaz" // 假设这是明文密码
p := []byte(plaintext)
newp, _ := EncryptByAes(p) // 开始加密
fmt.Println(newp)
}
基于上述加密后的密码，对其进行解密。
package main
import (
"crypto/aes"
"crypto/cipher"
"encoding/base64"
"errors"
"fmt"
)
var EncKey = []byte("QAZWSXEDCRFVTGBY") // 16位密码串
func pkcs7UnPadding(data []byte) ([]byte, error) {
length := len(data)
if length == 0 {
return nil, errors.New("Sorry, the encryption string is wrong.")
}
unPadding := int(data[length-1])
return data[:(length - unPadding)], nil
}
func AesDecrypt(data []byte, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
blockSize := block.BlockSize()
blockMode := cipher.NewCBCDecrypter(block, key[:blockSize])
crypted := make([]byte, len(data))
blockMode.CryptBlocks(crypted, data)
crypted, err = pkcs7UnPadding(crypted)
if err != nil {
return nil, err
}
return crypted, nil
}
func DecryptByAes(data string) ([]byte, error) {
dataByte, err := base64.StdEncoding.DecodeString(data)
if err != nil {
return nil, err
}
return AesDecrypt(dataByte, EncKey)
}
func main() {
ciphertext := "+LxjKS8N+Kpy/HNxsSJMIw==" // 密文
pwd, _ := DecryptByAes(ciphertext) // 开始解密
fmt.Println(string(pwd))
}
package main
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"encoding/base64"
"errors"
"fmt"
"os"
)
var EncKey = []byte("QAZWSXEDCRFVTGBY") // 16位密码串
func pkcs7Padding(data []byte, blockSize int) []byte {
padding := blockSize - len(data)%blockSize
padText := bytes.Repeat([]byte{byte(padding)}, padding)
return append(data, padText...)
}
func pkcs7UnPadding(data []byte) ([]byte, error) {
length := len(data)
if length == 0 {
return nil, errors.New("Sorry, the encryption string is wrong.")
}
unPadding := int(data[length-1])
return data[:(length - unPadding)], nil
}
func AesEncrypt(data []byte, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
blockSize := block.BlockSize()
encryptBytes := pkcs7Padding(data, blockSize)
crypted := make([]byte, len(encryptBytes))
blockMode := cipher.NewCBCEncrypter(block, key[:blockSize])
blockMode.CryptBlocks(crypted, encryptBytes)
return crypted, nil
}
func AesDecrypt(data []byte, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
blockSize := block.BlockSize()
blockMode := cipher.NewCBCDecrypter(block, key[:blockSize])
crypted := make([]byte, len(data))
blockMode.CryptBlocks(crypted, data)
crypted, err = pkcs7UnPadding(crypted)
if err != nil {
return nil, err
}
return crypted, nil
}
func EncryptByAes(data []byte) (string, error) {
res, err := AesEncrypt(data, EncKey)
if err != nil {
return "", err
}
return base64.StdEncoding.EncodeToString(res), nil
}
func DecryptByAes(data string) ([]byte, error) {
dataByte, err := base64.StdEncoding.DecodeString(data)
if err != nil {
return nil, err
}
return AesDecrypt(dataByte, EncKey)
}
const help = `
Help description of encryption and decryption command line application
-h --help [Display help]
-e --encryption Plaintext string encryption
-d --decrypt Ciphertext string decryption
Example:
1. encryption example:
passctl -e "your plaintext password"
2. decryption example:
passctl -d "Your ciphertext string"
`
func main() {
args := os.Args[1]
if args == "-h" || args == "--help" {
fmt.Print(help)
} else if args == "-e" || args == "--encryption" {
plaintext := os.Args[2]
p := []byte(plaintext)
newp, _ := EncryptByAes(p)
fmt.Println(newp)
} else if args == "-d" || args == "--decrypt" {
ciphertext := os.Args[2]
a, _ := DecryptByAes(ciphertext)
fmt.Println(string(a))
} else {
fmt.Println("Invalid option")
}
}
# 编译 [root@devhost encryptionDecryption]# go build -o passctl main.go # 查看帮助 [root@devhost encryptionDecryption]# ./passctl -h Help description of encryption and decryption command line application -h --help [Display help] -e --encryption Plaintext string encryption -d --decrypt Ciphertext string decryption Example: 1. encryption example: passctl -e "your plaintext password" 2. decryption example: passctl -d "Your ciphertext string" # 加密 [root@devhost encryptionDecryption]# ./passctl -e abc123456 nGi3ls+2yghdv7o8Ly2Z+A== # 解密 [root@devhost encryptionDecryption]# ./passctl -d nGi3ls+2yghdv7o8Ly2Z+A== abc123456 [root@devhost encryptionDecryption]#
