89 lines
2.2 KiB
Go
89 lines
2.2 KiB
Go
package oss
|
||
|
||
import (
|
||
"crypto"
|
||
"crypto/md5"
|
||
"crypto/rsa"
|
||
"crypto/x509"
|
||
"encoding/base64"
|
||
"encoding/pem"
|
||
"errors"
|
||
"io/ioutil"
|
||
"net/http"
|
||
"regexp"
|
||
"strings"
|
||
"sync"
|
||
)
|
||
|
||
type authenticationType struct {
|
||
lock *sync.RWMutex
|
||
certificate map[string]*rsa.PublicKey
|
||
}
|
||
|
||
var (
|
||
authentication = authenticationType{lock: &sync.RWMutex{}, certificate: map[string]*rsa.PublicKey{}}
|
||
urlReg = regexp.MustCompile(`^http(|s)://gosspublic.alicdn.com/[0-9a-zA-Z]`)
|
||
)
|
||
|
||
//验证OSS向业务服务器发来的回调函数。
|
||
//该方法是并发安全的
|
||
//pubKeyUrl 回调请求头中[x-oss-pub-key-url]一项，以Base64编码
|
||
//reqUrl oss所发来请求的url，由path+query组成
|
||
//reqBody oss所发来请求的body
|
||
//authorization authorization为回调头中的签名
|
||
func AuthenticateCallBack(pubKeyUrl, reqUrl, reqBody, authorization string) error {
|
||
//获取证书url
|
||
keyURL, err := base64.URLEncoding.DecodeString(pubKeyUrl)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
url := string(keyURL)
|
||
//判断证书是否来自于阿里云
|
||
if !urlReg.Match(keyURL) {
|
||
return errors.New("certificate address error")
|
||
}
|
||
//获取文件名
|
||
rs := []rune(url)
|
||
filename := string(rs[strings.LastIndex(url, "/") : len(rs)-1])
|
||
authentication.lock.RLock()
|
||
certificate := authentication.certificate[filename]
|
||
authentication.lock.RUnlock()
|
||
//内存中没有证书，下载
|
||
if certificate == nil {
|
||
authentication.lock.Lock()
|
||
res, err := http.Get(url)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
defer res.Body.Close()
|
||
body, err := ioutil.ReadAll(res.Body)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
block, _ := pem.Decode(body)
|
||
if block == nil {
|
||
return errors.New("certificate error")
|
||
}
|
||
pubKey, err := x509.ParsePKIXPublicKey(block.Bytes)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
certificate = pubKey.(*rsa.PublicKey)
|
||
authentication.certificate[filename] = certificate
|
||
authentication.lock.Unlock()
|
||
}
|
||
//证书准备完毕，开始验证
|
||
//解析签名
|
||
signature, err := base64.StdEncoding.DecodeString(authorization)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
hashed := md5.New()
|
||
hashed.Write([]byte(reqUrl + "\n" + reqBody))
|
||
if err := rsa.VerifyPKCS1v15(certificate, crypto.MD5, hashed.Sum(nil), signature); err != nil {
|
||
return err
|
||
}
|
||
//验证通过
|
||
return nil
|
||
}
|