什么是AES
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，是美国联邦政府采用的一种区块加密标准。
go实现aes加密
在golang的标准库aes可以实现AES加密，官方标准库aes文档链接：https://pkg.go.dev/crypto/aes
小案例需求
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。
实战
加密代码
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) }
解密代码
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)) }
实现passctl命令行应用
代码
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") } }
编译成二进制后使用
# 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]#
