11.md

Go中生成公钥和私钥

[toc]

用到的包

import (
	rsa "cryto/rsa"    //通过rsa的GenerateKey的方法来生成私钥
	rand "cryto/rand"   //rand是生成随机数的包
	x "cryto/x509"   //编码和解码
	pem "cryto/pem"   //通过pem将设置好的数据进行编码，并写入到磁盘文件
	f "fmt"
)

在生成公钥的过程中，公钥信息需要从得到的私钥对象中将公钥信息取出

代码

package main

import (
	"crypto/rand"
	"crypto/rsa"
	"crypto/x509"
	"encoding/pem"
	"fmt"
	"os"
)

//生成RSA私钥和公钥，保存到文件中
func GenerateRSAKey(bits int) {
	//GenerateKey函数使用随机数据生成器random生成一对具有指定字位数的RSA密钥
	//Reader是一个全局、共享的密码用强随机数生成器
	privateKey, err := rsa.GenerateKey(rand.Reader, bits)
	if err != nil {
		panic(err)
	}
	//保存私钥
	//通过x509标准将得到的ras私钥序列化为ASN.1 的 DER编码字符串
	X509PrivateKey := x509.MarshalPKCS1PrivateKey(privateKey)
	//使用pem格式对x509输出的内容进行编码
	//创建文件保存私钥
	privateFile, err := os.Create("private.pem")
	if err != nil {
		panic(err)
	}
	defer privateFile.Close()
	//构建一个pem.Block结构体对象
	privateBlock := pem.Block{Type: "RSA Private Key", Bytes: X509PrivateKey}
	//将数据保存到文件
	pem.Encode(privateFile, &privateBlock)

	//保存公钥
	//获取公钥的数据
	publicKey := privateKey.PublicKey
	//X509对公钥编码
	X509PublicKey, err := x509.MarshalPKIXPublicKey(&publicKey)
	if err != nil {
		panic(err)
	}
	//pem格式编码
	//创建用于保存公钥的文件
	publicFile, err := os.Create("public.pem")
	if err != nil {
		panic(err)
	}
	defer publicFile.Close()
	//创建一个pem.Block结构体对象
	publicBlock := pem.Block{Type: "RSA Public Key", Bytes: X509PublicKey}
	//保存到文件
	pem.Encode(publicFile, &publicBlock)
}

//RSA加密
func RSA_Encrypt(plainText []byte, path string) []byte {
	//打开文件
	file, err := os.Open(path)
	if err != nil {
		panic(err)
	}
	defer file.Close()
	//读取文件的内容
	info, _ := file.Stat()
	buf := make([]byte, info.Size())
	file.Read(buf)
	//pem解码
	block, _ := pem.Decode(buf)
	//x509解码

	publicKeyInterface, err := x509.ParsePKIXPublicKey(block.Bytes)
	if err != nil {
		panic(err)
	}
	//类型断言
	publicKey := publicKeyInterface.(*rsa.PublicKey)
	//对明文进行加密
	cipherText, err := rsa.EncryptPKCS1v15(rand.Reader, publicKey, plainText)
	if err != nil {
		panic(err)
	}
	//返回密文
	return cipherText
}

//RSA解密
func RSA_Decrypt(cipherText []byte, path string) []byte {
	//打开文件
	file, err := os.Open(path)
	if err != nil {
		panic(err)
	}
	defer file.Close()
	//获取文件内容
	info, _ := file.Stat()
	buf := make([]byte, info.Size())
	file.Read(buf)
	//pem解码
	block, _ := pem.Decode(buf)
	//X509解码
	privateKey, err := x509.ParsePKCS1PrivateKey(block.Bytes)
	if err != nil {
		panic(err)
	}
	//对密文进行解密
	plainText, _ := rsa.DecryptPKCS1v15(rand.Reader, privateKey, cipherText)
	//返回明文
	return plainText
}

//测试函数
func main() {
	//生成密钥对，保存到文件
	GenerateRSAKey(2048)
	message := []byte("hello world")
	//加密
	cipherText := RSA_Encrypt(message, "public.pem")
	fmt.Println("加密后为：", string(cipherText))
	//解密
	plainText := RSA_Decrypt(cipherText, "private.pem")
	fmt.Println("解密后为：", string(plainText))
}

查看生成的密钥

公钥文件

-----BEGIN RSA Public Key-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAv3+qRiCs3YHPP+Og0fzP
rOFNRK8rUB9LqrSTWLx1vfoa83gti2LKRkSwf1TXqgYOssHk0xWPHIGKpJFzn9rD
GkGZRKEGuCX6pG2UKNAyaglkaSTnCBN8YWLxoovqLFamIiMAtvxdp0ZQHE7rB9j8
KwUnpgMdyUIrHn5mLgsT253zXr7KO2suCBZM1h6GSWXVDj/OEVy2aL5CztOZigRf
xEBsee8VBH3FgJWTKk/AEvbhAyxi354HNeiNRHNgXIosJHndvPWJht4BtaIhk1jf
EN4z5QedJJXCXmHLob2QDmtwgyA+nlxyYg2EHV6u9PMNiBPVm1bA3zpOdEiVm34M
rwIDAQAB
-----END RSA Public Key-----

私钥文件

-----BEGIN RSA Private Key-----
MIIEpAIBAAKCAQEAv3+qRiCs3YHPP+Og0fzPrOFNRK8rUB9LqrSTWLx1vfoa83gt
i2LKRkSwf1TXqgYOssHk0xWPHIGKpJFzn9rDGkGZRKEGuCX6pG2UKNAyaglkaSTn
CBN8YWLxoovqLFamIiMAtvxdp0ZQHE7rB9j8KwUnpgMdyUIrHn5mLgsT253zXr7K
O2suCBZM1h6GSWXVDj/OEVy2aL5CztOZigRfxEBsee8VBH3FgJWTKk/AEvbhAyxi
354HNeiNRHNgXIosJHndvPWJht4BtaIhk1jfEN4z5QedJJXCXmHLob2QDmtwgyA+
nlxyYg2EHV6u9PMNiBPVm1bA3zpOdEiVm34MrwIDAQABAoIBAQCbD7oF3PF8z17N
Afm37zkOaMUTZ6/vydeQW3WwdbH1ae6m1No0MoNNkNNF16JmB0+hiYVLMvrV/0MP
bMOuXgp7WUDNJIJ3XDFvMVe2EJex6vcGeJ4mmPivNtooX5j33BXcMHGkugbvquy1
b2W6zgWqpBrtvzpAPDcEEx+UCt5ChmX2YL0wzXpEMU0bFREAmksW/vnYyKKEjqdo
S/rMoMLyl9IG1xSlAO0APSKhYJir5vG4V4lQr3wKGtBofKWhn5mgYwL/rQMbLIxA
IB56/bn2QXqThnYSGy6l7spot944/xlUHq+Dh3Fl6AkAggJQLn5G8L3gH2TZOOFG
l82Gz/PBAoGBANy1XMhDVNM6aOxsBeA+eR1F2GnSQfipD1ZA9LpuS/0YVnGSlpdT
HqrUY6EYcyPQHrglDqmOllofUJLbsE7pnDcj5+4t4fO3m/CsqLUIOoGIAu7cABjt
9XdbemnBxffqrE+81Exi0VNYNo7frqNf/g8xxQ065n5dmzt7vPCs2mlhAoGBAN4e
nBPNF4Cj7oFWRfS/0mJ6H3+5xiANmyLDQcZJEGI7GBcwYIaMqsUgUefjcrYz4cQn
Wq2Mq9JrRsWTB8gsrhR+c51QggxbHDDIskQHuounKgYUtBcw509EALi8KBdWSrdh
syjOdhkkR0cX8Gn4FpJgcWznKNqPBiXl+Ox+neAPAoGBAKk9cQ4ng04NxhM0qjTP
8vNdcZuDnQ7eJGKRoJesqBxFo1Ongk47cJKyFkubgf7+QfAWim2+ZtBontJeH44D
WMR3hgt/p3nJW4xr+VoIG0TkVMtwa6qyHb4OqYmbCwEWNFdYhrqkM7tjM0LPhwzE
OP7RvTZt6f0QLk6ojbNH+JtBAoGARR6tXxQRXjylOaZJOrJ+m5p5NtvupYbWYej1
DOkrqgXNp1msj/IyKgm2szx6M+zNMqc0dpEx3tb3PQBWCZqtyT7YZ3noHkQz75Jk
tvrYuCCa2S2UJStYr7fvqY0TxL9bnNlQUUB+S7CYZa0zaSaEj6RnZ4Y/llOvjBeW
cLGuG00CgYBHNSGgRm49vl97CKZX+grIdW7icOZtrI7aaXQSOUuat36ie4SgIUgb
w2TZituP4h9wTdRyNqY3j4yzAzC6tCNPYO3zteUxRJprNJp9nmbddDL0Ro6Rzc3c
Dt0srfd1CstgQYcDIkACvwHdVbxEO9+8TPaM3/UbXmQ4yoooN87f+A==
-----END RSA Private Key-----