创建并使用https证书

目录

• 前言
• 产生证书
• 测试https服务器
• 用tls加密tcp连接
• 总结

前言

https要比http更安全些，因此可以配置Nginx服务器使用证书，客户端就会去第三方平台校验证书。
但是我们自己的服务器和客户端只是想要加个密而已，也没必要跑去第三方平台校验证书，省钱方便。
因此研究了一下生成证书和使用证书的笔记。

产生证书

网上很多都是用openssl命令行去产生，有点麻烦，主要是不想记一堆命令，因此找到一个非常简单的项目。
项目地址：https://github.com/michaelklishin/tls-gen，需要环境有python3、openssl、make这三个工具。
使用方法cd tls-gen/basic & make CN=www.janbar.com，这样客户端必须用该域名进行访问，并且要带上对应证书。
最终产生如下三个文件，testca/cacert.pem是客户端使用，server/cert.pem，server/key.pem是服务器使用。

testca/
  cacert.pem

server/
  cert.pem
  key.pem

记得在c:\Windows\System32\drivers\etc\hosts增加127.0.0.1 www.janbar.com,准备证书源码文件cert.go，内容如下：

var (
    certPEMBlock = []byte(`-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`)
    keyPEMBlock = []byte(`-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----`)
    rootPEM = []byte(`-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----`)
)

测试https服务器

测试代码文件test_https.go如下：

package main

import (
    "crypto/tls"
    "crypto/x509"
    "io"
    "net/http"
    "os"
    "time"
)

func main() {
    http.Handle("/", http.FileServer(http.Dir(".")))

    go func() {
        cf, err := tls.X509KeyPair(certPEMBlock, keyPEMBlock)
        if err != nil {
            panic(err)
        }
        err = (&http.Server{TLSConfig: &tls.Config{
            Certificates: []tls.Certificate{cf},
        }}).ListenAndServeTLS("", "")
        if err != nil {
            panic(err)
        }
    }()
    time.Sleep(time.Second)
    // 上面是http服务器的运行

    // 下面是http客服端访问
    roots := x509.NewCertPool()
    ok := roots.AppendCertsFromPEM(rootPEM)
    if !ok {
        panic("failed to parse root certificate")
    }

    client := &http.Client{Transport: &http.Transport{
        TLSClientConfig: &tls.Config{RootCAs: roots},
    }}

    req, err := http.NewRequest(http.MethodGet, "https://www.janbar.com", nil)
    if err != nil {
        panic(err)
    }
    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }
    io.Copy(os.Stdout, resp.Body)
    resp.Body.Close()
}

执行go run test_https.go cert.go效果如下，显示了运行目录下的文件列表：

<pre>
<a href="test.exe">test.exe</a>
<a href="test.go">test.go</a>
</pre>

用tls加密tcp连接

测试代码test_tcp.go文件，源码如下：

package main

import (
    "crypto/tls"
    "crypto/x509"
    "fmt"
    "net"
    "time"
)

func main() {
    addr := "www.janbar.com:8080"
    go func() {
        err := tcpServer(addr)
        if err != nil {
            panic(err)
        }
    }()
    time.Sleep(time.Second)
    err := tcpClient(addr)
    if err != nil {
        panic(err)
    }
}

func tcpServer(addr string) error {
    cf, err := tls.X509KeyPair(certPEMBlock, keyPEMBlock)
    if err != nil {
        return err
    }
    s, err := tls.Listen("tcp", addr, &tls.Config{Certificates: []tls.Certificate{cf}})
    if err != nil {
        return err
    }
    defer s.Close()

    client := func(c net.Conn) error {
        tNow := time.Now().String()
        buf := make([]byte, len(tNow))
        n, err := c.Read(buf)
        if err != nil {
            return err
        }
        fmt.Printf("server [%s]\n", buf[:n])
        _, err = c.Write([]byte(tNow))
        return err
    }

    for {
        l, err := s.Accept()
        if err != nil {
            return err
        }
        go func(c net.Conn) {
            defer c.Close()
            if err := client(c); err != nil {
                fmt.Println(err)
            }
        }(l)
    }
}

func tcpClient(addr string) error {
    roots := x509.NewCertPool()
    ok := roots.AppendCertsFromPEM(rootPEM)
    if !ok {
        panic("failed to parse root certificate")
    }
    c, err := tls.Dial("tcp", addr, &tls.Config{RootCAs: roots})
    if err != nil {
        return err
    }
    defer c.Close()

    tNow := time.Now().String()
    c.Write([]byte(tNow))
    buf := make([]byte, len(tNow))
    n, err := c.Read(buf)
    if err != nil {
        return err
    }
    fmt.Printf("client [%s]\n", buf[:n])
    return nil
}

执行go run test_tcp.go cert.go效果如下：

server [2021-01-21 21:09:51.7942154 +0800 CST m=+1.011929701]
client [2021-01-21 21:09:51.7852425 +0800 CST m=+1.002956801]

总结

以前使用的tcp连接没有任何加密，现在想想还是不安全。用上证书，起码会校验访问域名和证书等信息，多少会安全一些。
以上都是用来测试等等，如果需要正式使用证书，还是去各大网站花钱申请吧。我一直用万网的免费证书，但是有效期只有一年额。