How to generate a public-private key pair for asymmetric cryptography in Go?

To generate a public-private key pair for asymmetric cryptography in Go, you can use the crypto package's rsa subpackage. Here's an example of how to do it:

package main

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

func main() {
	// Generate a private key
	privateKey, err := rsa.GenerateKey(rand.Reader, 2048)
	if err != nil {
		fmt.Printf("Failed to generate private key: %v", err)
		return
	}

	// Extract the public key from the private key
	publicKey := &privateKey.PublicKey

	// Encode the private key to PEM format
	privateKeyPEM := &pem.Block{
		Type:  "RSA PRIVATE KEY",
		Bytes: x509.MarshalPKCS1PrivateKey(privateKey),
	}

	// Write the private key PEM to a file
	privateKeyFile, err := os.Create("private_key.pem")
	if err != nil {
		fmt.Printf("Failed to create private key file: %v", err)
		return
	}
	defer privateKeyFile.Close()
	if err := pem.Encode(privateKeyFile, privateKeyPEM); err != nil {
		fmt.Printf("Failed to write private key PEM: %v", err)
		return
	}

	// Encode the public key to PEM format
	publicKeyPEM, err := x509.MarshalPKIXPublicKey(publicKey)
	if err != nil {
		fmt.Printf("Failed to encode public key: %v", err)
		return
	}

	// Write the public key PEM to a file
	publicKeyFile, err := os.Create("public_key.pem")
	if err != nil {
		fmt.Printf("Failed to create public key file: %v", err)
		return
	}
	defer publicKeyFile.Close()
	if err := pem.Encode(publicKeyFile, &pem.Block{Type: "PUBLIC KEY", Bytes: publicKeyPEM}); err != nil {
		fmt.Printf("Failed to write public key PEM: %v", err)
		return
	}

	fmt.Println("Key pair generated successfully!")
}

This code will generate a 2048-bit RSA key pair and save the private key PEM to private_key.pem and the public key PEM to public_key.pem. You can adjust the key size according to your needs.