加密解密在实际开发中应用比较广泛,常用加解密分为:“对称式”、“非对称式”和”数字签名“。
对称式:对称加密(也叫私钥加密)指加密和解密使用相同密钥的加密算法。具体算法主要有DES算法,3DES算法,TDEA算法,Blowfish算法,RC5算法,IDEA算法。
非对称加密(公钥加密):指加密和解密使用不同密钥的加密算法,也称为公私钥加密。具体算法主要有RSA、Elgamal、背包算法、Rabin、D-H、ECC(椭圆曲线加密算法)。
数字签名:数字签名是非对称密钥加密技术与数字摘要技术的应用。主要算法有md5、hmac、sha1等。
以下介绍golang语言主要的加密解密算法实现。
MD5信息摘要算法是一种被广泛使用的密码散列函数,可以产生出一个128位(16进制,32个字符)的散列值(hash value),用于确保信息传输完整一致。
func GetMd5String(s string) string {
h := md5.New()
h.Write([]byte(s))
return hex.EncodeToString(h.Sum(nil))
}
HMAC是密钥相关的哈希运算消息认证码(Hash-based Message Authentication Code)的缩写,
它通过一个标准算法,在计算哈希的过程中,把key混入计算过程中。
和我们自定义的加salt算法不同,Hmac算法针对所有哈希算法都通用,无论是MD5还是SHA-1。采用Hmac替代我们自己的salt算法,可以使程序算法更标准化,也更安全。
示例
//key随意设置 data 要加密数据
func Hmac(key, data string) string {
hash:= hmac.New(md5.New, []byte(key)) // 创建对应的md5哈希加密算法
hash.Write([]byte(data))
return hex.EncodeToString(hash.Sum([]byte("")))
}
func HmacSha256(key, data string) string {
hash:= hmac.New(sha256.New, []byte(key)) //创建对应的sha256哈希加密算法
hash.Write([]byte(data))
return hex.EncodeToString(hash.Sum([]byte("")))
}
SHA-1可以生成一个被称为消息摘要的160位(20字节)散列值,散列值通常的呈现形式为40个十六进制数。
func Sha1(data string) string {
sha1 := sha1.New()
sha1.Write([]byte(data))
return hex.EncodeToString(sha1.Sum([]byte("")))
}
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。这个标准用来替代原先的DES(Data Encryption Standard),已经被多方分析且广为全世界所使用。AES中常见的有三种解决方案,分别为AES-128、AES-192和AES-256。如果采用真正的128位加密技术甚至256位加密技术,蛮力攻击要取得成功需要耗费相当长的时间。
AES 有五种加密模式:
电码本模式(Electronic Codebook Book (ECB))、
密码分组链接模式(Cipher Block Chaining (CBC))、
计算器模式(Counter (CTR))、
密码反馈模式(Cipher FeedBack (CFB))
输出反馈模式(Output FeedBack (OFB))
ECB模式
出于安全考虑,golang默认并不支持ECB模式。
package main
import (
"crypto/aes"
"fmt"
)
func AESEncrypt(src []byte, key []byte) (encrypted []byte) {
cipher, _ := aes.NewCipher(generateKey(key))
length := (len(src) + aes.BlockSize) / aes.BlockSize
plain := make([]byte, length*aes.BlockSize)
copy(plain, src)
pad := byte(len(plain) - len(src))
for i := len(src); i < len(plain); i++ {
plain[i] = pad
}
encrypted = make([]byte, len(plain))
// 分组分块加密
for bs, be := 0, cipher.BlockSize(); bs <= len(src); bs, be = bs+cipher.BlockSize(), be+cipher.BlockSize() {
cipher.Encrypt(encrypted[bs:be], plain[bs:be])
}
return encrypted
}
func AESDecrypt(encrypted []byte, key []byte) (decrypted []byte) {
cipher, _ := aes.NewCipher(generateKey(key))
decrypted = make([]byte, len(encrypted))
//
for bs, be := 0, cipher.BlockSize(); bs < len(encrypted); bs, be = bs+cipher.BlockSize(), be+cipher.BlockSize() {
cipher.Decrypt(decrypted[bs:be], encrypted[bs:be])
}
trim := 0
if len(decrypted) > 0 {
trim = len(decrypted) - int(decrypted[len(decrypted)-1])
}
return decrypted[:trim]
}
func generateKey(key []byte) (genKey []byte) {
genKey = make([]byte, 16)
copy(genKey, key)
for i := 16; i < len(key); {
for j := 0; j < 16 && i < len(key); j, i = j+1, i+1 {
genKey[j] ^= key[i]
}
}
return genKey
}
func main() {
source:="hello world"
fmt.Println("原字符:",source)
//16byte密钥
key:="1443flfsaWfdas"
encryptCode:=AESEncrypt([]byte(source),[]byte(key))
fmt.Println("密文:",string(encryptCode))
decryptCode:=AESDecrypt(encryptCode,[]byte(key))
fmt.Println("解密:",string(decryptCode))
}
CBC模式
package main
import(
"bytes"
"crypto/aes"
"fmt"
"crypto/cipher"
"encoding/base64"
)
func main() {
orig := "hello world"
key := "0123456789012345"
fmt.Println("原文:", orig)
encryptCode := AesEncrypt(orig, key)
fmt.Println("密文:" , encryptCode)
decryptCode := AesDecrypt(encryptCode, key)
fmt.Println("解密结果:", decryptCode)
}
func AesEncrypt(orig string, key string) string {
// 转成字节数组
origData := []byte(orig)
k := []byte(key)
// 分组秘钥
// NewCipher该函数限制了输入k的长度必须为16, 24或者32
block, _ := aes.NewCipher(k)
// 获取秘钥块的长度
blockSize := block.BlockSize()
// 补全码
origData = PKCS7Padding(origData, blockSize)
// 加密模式
blockMode := cipher.NewCBCEncrypter(block, k[:blockSize])
// 创建数组
cryted := make([]byte, len(origData))
// 加密
blockMode.CryptBlocks(cryted, origData)
return base64.StdEncoding.EncodeToString(cryted)
}
func AesDecrypt(cryted string, key string) string {
// 转成字节数组
crytedByte, _ := base64.StdEncoding.DecodeString(cryted)
k := []byte(key)
// 分组秘钥
block, _ := aes.NewCipher(k)
// 获取秘钥块的长度
blockSize := block.BlockSize()
// 加密模式
blockMode := cipher.NewCBCDecrypter(block, k[:blockSize])
// 创建数组
orig := make([]byte, len(crytedByte))
// 解密
blockMode.CryptBlocks(orig, crytedByte)
// 去补全码
orig = PKCS7UnPadding(orig)
return string(orig)
}
//补码
//AES加密数据块分组长度必须为128bit(byte[16]),密钥长度可以是128bit(byte[16])、192bit(byte[24])、256bit(byte[32])中的任意一个。
func PKCS7Padding(ciphertext []byte, blocksize int) []byte {
padding := blocksize - len(ciphertext)%blocksize
padtext := bytes.Repeat([]byte{byte(padding)}, padding)
return append(ciphertext, padtext...)
}
//去码
func PKCS7UnPadding(origData []byte) []byte {
length := len(origData)
unpadding := int(origData[length-1])
return origData[:(length - unpadding)]
}
CRT模式
package main
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"fmt"
)
//加密
func aesCtrCrypt(plainText []byte, key []byte) ([]byte, error) {
//1. 创建cipher.Block接口
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
//2. 创建分组模式,在crypto/cipher包中
iv := bytes.Repeat([]byte("1"), block.BlockSize())
stream := cipher.NewCTR(block, iv)
//3. 加密
dst := make([]byte, len(plainText))
stream.XORKeyStream(dst, plainText)
return dst, nil
}
func main() {
source:="hello world"
fmt.Println("原字符:",source)
key:="1443flfsaWfdasds"
encryptCode,_:=aesCtrCrypt([]byte(source),[]byte(key))
fmt.Println("密文:",string(encryptCode))
decryptCode,_:=aesCtrCrypt(encryptCode,[]byte(key))
fmt.Println("解密:",string(decryptCode))
}
CFB模式
package main
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"encoding/hex"
"fmt"
"io"
)
func AesEncryptCFB(origData []byte, key []byte) (encrypted []byte) {
block, err := aes.NewCipher(key)
if err != nil {
//panic(err)
}
encrypted = make([]byte, aes.BlockSize+len(origData))
iv := encrypted[:aes.BlockSize]
if _, err := io.ReadFull(rand.Reader, iv); err != nil {
//panic(err)
}
stream := cipher.NewCFBEncrypter(block, iv)
stream.XORKeyStream(encrypted[aes.BlockSize:], origData)
return encrypted
}
func AesDecryptCFB(encrypted []byte, key []byte) (decrypted []byte) {
block, _ := aes.NewCipher(key)
if len(encrypted) < aes.BlockSize {
panic("ciphertext too short")
}
iv := encrypted[:aes.BlockSize]
encrypted = encrypted[aes.BlockSize:]
stream := cipher.NewCFBDecrypter(block, iv)
stream.XORKeyStream(encrypted, encrypted)
return encrypted
}
func main() {
source:="hello world"
fmt.Println("原字符:",source)
key:="ABCDEFGHIJKLMNO1"//16位
encryptCode:=AesEncryptCFB([]byte(source),[]byte(key))
fmt.Println("密文:",hex.EncodeToString(encryptCode))
decryptCode:=AesDecryptCFB(encryptCode,[]byte(key))
fmt.Println("解密:",string(decryptCode))
}
OFB模式
package main
import (
"bytes"
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"encoding/hex"
"fmt"
"io"
)
func aesEncryptOFB( data[]byte,key []byte) ([]byte, error) {
data = PKCS7Padding(data, aes.BlockSize)
block, _ := aes.NewCipher([]byte(key))
out := make([]byte, aes.BlockSize + len(data))
iv := out[:aes.BlockSize]
if _, err := io.ReadFull(rand.Reader, iv); err != nil {
return nil, err
}
stream := cipher.NewOFB(block, iv)
stream.XORKeyStream(out[aes.BlockSize:], data)
return out, nil
}
func aesDecryptOFB( data[]byte,key []byte) ([]byte, error) {
block, _ := aes.NewCipher([]byte(key))
iv := data[:aes.BlockSize]
data = data[aes.BlockSize:]
if len(data) % aes.BlockSize != 0 {
return nil, fmt.Errorf("data is not a multiple of the block size")
}
out := make([]byte, len(data))
mode := cipher.NewOFB(block, iv)
mode.XORKeyStream(out, data)
out= PKCS7UnPadding(out)
return out, nil
}
//补码
//AES加密数据块分组长度必须为128bit(byte[16]),密钥长度可以是128bit(byte[16])、192bit(byte[24])、256bit(byte[32])中的任意一个。
func PKCS7Padding(ciphertext []byte, blocksize int) []byte {
padding := blocksize - len(ciphertext)%blocksize
padtext := bytes.Repeat([]byte{byte(padding)}, padding)
return append(ciphertext, padtext...)
}
//去码
func PKCS7UnPadding(origData []byte) []byte {
length := len(origData)
unpadding := int(origData[length-1])
return origData[:(length - unpadding)]
}
func main() {
source:="hello world"
fmt.Println("原字符:",source)
key:="1111111111111111"//16位 32位均可
encryptCode,_:=aesEncryptOFB([]byte(source),[]byte(key))
fmt.Println("密文:",hex.EncodeToString(encryptCode))
decryptCode,_:=aesDecryptOFB(encryptCode,[]byte(key))
fmt.Println("解密:",string(decryptCode))
}
首先使用openssl
生成公私钥
package main
import (
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"encoding/base64"
"encoding/pem"
"errors"
"fmt"
)
// 私钥生成
//openssl genrsa -out rsa_private_key.pem 1024
var privateKey = []byte(`
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
`)
// 公钥: 根据私钥生成
//openssl rsa -in rsa_private_key.pem -pubout -out rsa_public_key.pem
var publicKey = []byte(`
-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDcGsUIIAINHfRTdMmgGwLrjzfM
NSrtgIf4EGsNaYwmC1GjF/bMh0Mcm10oLhNrKNYCTTQVGGIxuc5heKd1gOzb7bdT
nCDPPZ7oV7p1B9Pud+6zPacoqDz2M24vHFWYY2FbIIJh8fHhKcfXNXOLovdVBE7Z
y682X1+R1lRK8D+vmQIDAQAB
-----END PUBLIC KEY-----
`)
// 加密
func RsaEncrypt(origData []byte) ([]byte, error) {
//解密pem格式的公钥
block, _ := pem.Decode(publicKey)
if block == nil {
return nil, errors.New("public key error")
}
// 解析公钥
pubInterface, err := x509.ParsePKIXPublicKey(block.Bytes)
if err != nil {
return nil, err
}
// 类型断言
pub := pubInterface.(*rsa.PublicKey)
//加密
return rsa.EncryptPKCS1v15(rand.Reader, pub, origData)
}
// 解密
func RsaDecrypt(ciphertext []byte) ([]byte, error) {
//解密
block, _ := pem.Decode(privateKey)
if block == nil {
return nil, errors.New("private key error!")
}
//解析PKCS1格式的私钥
priv, err := x509.ParsePKCS1PrivateKey(block.Bytes)
if err != nil {
return nil, err
}
// 解密
return rsa.DecryptPKCS1v15(rand.Reader, priv, ciphertext)
}
func main() {
data, _ := RsaEncrypt([]byte("hello world"))
fmt.Println(base64.StdEncoding.EncodeToString(data))
origData, _ := RsaDecrypt(data)
fmt.Println(string(origData))
}
参考:
https://www.liaoxuefeng.com/wiki/1016959663602400/1183198304823296
https://studygolang.com/articles/15642?fr=sidebar
https://segmentfault.com/a/1190000004151272