golang SSL加密465端口发送邮件

> TCP 25端口是默认的邮箱服务端口。阿里云 基于安全考虑 云服务器ECS的25端口默认受限。使用SSL加密465端口发信。**下面的例子为用465端口进行发送邮件**

```golang
package main

import (
	"crypto/tls"
	"fmt"
	"net"
	"net/smtp"
	"strings"
)

func main(){
	host := "smtp.126.com"
	port := 465
	email  := "xxxx@126.com" // 发送邮箱
	pwd := "xxxxxxx"  // 邮箱密码
	toEmail := "xxxx@126.com;abc@qq.com"  // 目标地址

header   :=  make(map[string]string)

header["From"] = "test"+"<" +email+">"
	header["To"] = toEmail
	header["Subject"] = "abc邮件标题12344"
	header["Content-Type"] = "text/html;charset=UTF-8"
	text := "您好！！！！"
	body := `
    <html>
    <body>
    <h3>
    "测试通过golang发送邮件"` + text + `
    </h3>
    </body>
    </html>
    `

message := ""

for k,v :=range header{
		message  += fmt.Sprintf("%s:%s\r\n",k,v)
	}

message +="\r\n"+body

auth :=smtp.PlainAuth(
		"",
		email,
		pwd,
		host,
	)

err := SendMailUsingTLS(
		fmt.Sprintf("%s:%d", host, port),
		auth,
		email,
		toEmail,
		[]byte(message),
	)

if err  !=nil {
		fmt.Println("发送邮件失败!")
		fmt.Println(err)
	} else {
		fmt.Println("发送邮件成功!")
	}

}

func SendMailUsingTLS(addr string, auth smtp.Auth, from string,to string, msg []byte) (err error) {
	c, err := Dial(addr)
	if err != nil {
		return err
	}
	defer c.Close()

if auth != nil {
		if ok, _ := c.Extension("AUTH"); ok {
			if err = c.Auth(auth); err != nil {
				return err
			}
		}
	}

if err = c.Mail(from); err != nil {
		return err
	}

tos := strings.Split(to,";")

for _, addr := range tos {
		if err = c.Rcpt(addr); err != nil {
			fmt.Print(err)
			return err

}
	}

w, err := c.Data()
	if err != nil {
		return err
	}

_, err = w.Write(msg)
	if err != nil {
		return err
	}

err = w.Close()
	if err != nil {
		return err
	}
	return c.Quit()
}

func Dial(addr string) (*smtp.Client, error) {
	conn, err := tls.Dial("tcp", addr, nil)
	if err != nil {
		return nil, err
	}
	//分解主机端口字符串
	host, _, _ := net.SplitHostPort(addr)
	return smtp.NewClient(conn, host)
}
```

golang SSL加密465端口 发送邮件

golang SSL加密465端口发送邮件