matcher.go

package main

import (
	"fmt"
	"io/ioutil"
	"os/exec"
	"strings"
)

func opensslModulus(command string, content string) (string, error) {
	cmd := exec.Command("openssl", command, "-noout", "-modulus")
	cmd.Stdin = strings.NewReader(content)
	out, err := cmd.Output()

	if err != nil {
		return "", err
	}
	return string(out), nil
}

func main() {
	crt, err := ioutil.ReadFile("server.crt")
	if err != nil {
		panic(err)
	}
	key, err := ioutil.ReadFile("server.key")
	if err != nil {
		panic(err)
	}

	mkey, err := opensslModulus("x509", string(crt))
	if err != nil {
		panic(err)
	}
	mcrt, err := opensslModulus("rsa", string(key))
	if err != nil {
		panic(err)
	}

	fmt.Println(string(mkey))
	fmt.Println(string(mcrt))
}