Golang加密解密之RSA（附带php）

Golang加密解密之RSA

RSA是非对称加密中常用的算法。首先要了解非对称加密和对称加密的区别：

• 对称加密：加解密使用同一把密钥
• 非对称加密：加解密使用一对公私钥

非对称加密最常见的方式就是RSA，接下来我们就主要介绍RSA的加密解密过程。

生成RSA公私钥对

Golang

Golang中使用crypto库来生成RSA公私钥对。下面是生成2048位RSA公私钥对的示例代码：

package main

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

func main() {
    bitSize := 2048

    privateKey, err := rsa.GenerateKey(rand.Reader, bitSize)
    if err != nil {
        panic(err)
    }

    derPrivateKey := x509.MarshalPKCS1PrivateKey(privateKey)
    privateKeyBlock := pem.Block{
        Type:  "RSA PRIVATE KEY",
        Bytes: derPrivateKey,
    }

    privateKeyFile, err := os.Create("private.pem")
    if err != nil {
        panic(err)
    }
    defer privateKeyFile.Close()

    err = pem.Encode(privateKeyFile, &privateKeyBlock)
    if err != nil {
        panic(err)
    }

    publicKey := privateKey.PublicKey
    derPublicKey, err := x509.MarshalPKIXPublicKey(&publicKey)
    if err != nil {
        panic(err)
    }

    publicKeyBlock := pem.Block{
        Type:  "PUBLIC KEY",
        Bytes: derPublicKey,
    }

    publicKeyFile, err := os.Create("public.pem")
    if err != nil {
        panic(err)
    }
    defer publicKeyFile.Close()

    err = pem.Encode(publicKeyFile, &publicKeyBlock)
    if err != nil {
        panic(err)
    }

    fmt.Println("RSA public and private keys generated")
}

运行上述代码会在当前目录下生成名为public.pem和private.pem的PEM格式公私钥文件。

PHP

在PHP中也可以通过openssl扩展来生成RSA公私钥对，示例代码如下：

$privateKey = openssl_pkey_new([
    "digest_alg" => "sha512",
    "private_key_bits" => 2048,
    "private_key_type" => OPENSSL_KEYTYPE_RSA,
]);

if (!$privateKey) {
    die("Failed to generate private key");
}

openssl_pkey_export_to_file($privateKey, "private.pem");

$details = openssl_pkey_get_details($privateKey);
$publicKey = $details['key'];
openssl_pkey_export_to_file($publicKey, "public.pem");

echo "RSA public and private keys generated";

运行上述代码会在当前目录下生成名为public.pem和private.pem的PEM格式公私钥文件。

RSA加密解密

Golang

Golang中使用crypto/rsa库来进行RSA加密解密。下面是示例代码：

package main

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

func main() {
    message := "Hello, RSA"

    privateKeyPEM, err := ioutil.ReadFile("private.pem")
    if err != nil {
        panic(err)
    }

    privateKeyBlock, _ := pem.Decode(privateKeyPEM)
    privateKey, err := x509.ParsePKCS1PrivateKey(privateKeyBlock.Bytes)
    if err != nil {
        panic(err)
    }

    ciphertext, err := rsa.EncryptPKCS1v15(rand.Reader, &privateKey.PublicKey, []byte(message))
    if err != nil {
        panic(err)
    }

    fmt.Printf("RSA encrypted message: %x\n", ciphertext)

    publicKeyPEM, err := ioutil.ReadFile("public.pem")
    if err != nil {
        panic(err)
    }

    publicKeyBlock, _ := pem.Decode(publicKeyPEM)
    publicKeyInterface, err := x509.ParsePKIXPublicKey(publicKeyBlock.Bytes)
    if err != nil {
        panic(err)
    }
    publicKey := publicKeyInterface.(*rsa.PublicKey)

    plaintext, err := rsa.DecryptPKCS1v15(rand.Reader, privateKey, ciphertext)
    if err != nil {
        panic(err)
    }

    fmt.Printf("RSA decrypted message: %s\n", plaintext)
}

运行上述代码会将"Hello, RSA"字符串进行RSA加密后再解密，并输出加密解密后的结果。

PHP

PHP也可以使用openssl扩展来实现RSA加密解密，示例代码如下：

$message = "Hello, RSA";

$publicKeyPEM = file_get_contents("public.pem");
$publicKey = openssl_pkey_get_public($publicKeyPEM);
if (!$publicKey) {
    die("Failed to get public key");
}
$ciphertext = "";
$success = openssl_public_encrypt($message, $ciphertext, $publicKey, OPENSSL_PKCS1_PADDING);
if (!$success) {
    die("Failed to encrypt message");
}

echo "RSA encrypted message: " . bin2hex($ciphertext) . "\n";

$privateKeyPEM = file_get_contents("private.pem");
$privateKey = openssl_pkey_get_private($privateKeyPEM);
if (!$privateKey) {
    die("Failed to get private key");
}
$plaintext = "";
$success = openssl_private_decrypt($ciphertext, $plaintext, $privateKey, OPENSSL_PKCS1_PADDING);
if (!$success) {
    die("Failed to decrypt message");
}

echo "RSA decrypted message: " . $plaintext . "\n";

运行上述代码会将"Hello, RSA"字符串进行RSA加密后再解密，并输出加密解密后的结果。

总结

本文介绍了如何使用Golang和PHP来生成RSA公私钥对，以及如何使用Golang和PHP来进行RSA加密解密。通过学习本文，读者应该对RSA算法的特点和使用方法有所掌握。