Nginx实现JWT验证-基于OpenResty实现

介绍

权限认证是接口开发中不可避免的问题,权限认证包括两个方面

1. 接口需要知道调用的用户是谁
2. 接口需要知道该用户是否有权限调用

第1个问题偏向于架构，第2个问题更偏向于业务，因此考虑在架构层解决第1个问题，以达到以下目的

1. 所有请求被保护的接口保证是合法的(已经认证过的用户)
2. 接口可以从请求头中获取当前用户信息
3. 每个请求都有uuid用于标识

JWT(JSON Web Token)目前是应用最广的接口权限方案，具有无状态,跨系统,多语言多平台支持等特点，如果能在网关层实现JWT验证不仅可以避免代码入侵还能为整个后台提供统一的解决方案,目前客户网关使用Nginx,但社区版Nginx中没有JWT模块,自己实现不现实,因此选择OpenResty作为网关层, 据官网介绍,OpenResty® 是一个基于 Nginx 与 Lua 的高性能 Web 平台，其内部集成了大量精良的 Lua 库、第三方模块以及大多数的依赖项。用于方便地搭建能够处理超高并发、扩展性极高的动态 Web 应用、Web 服务和动态网关。本质上就是一个Nginx+Lua的集成软件.
整体架构如图：

实现

环境

[root@docker ~]# cat /etc/redhat-release CentOS Linux release 7.4.1708 (Core) [root@docker ~]# more /proc/version Linux version 3.10.0-693.el7.x86_64 ([e-mail]) (gcc version 4.8.5 20150623 (Red Hat 4. 8.5-16) (GCC) ) #1 SMP Tue Aug 22 21:09:27 UTC 2017

安装OpenResty

OpenRestry安装很简单,可以在这里找到不同版本操作系统安装文档,本次使用的环境是CentOS Linux release 7.4

[root@docker ~]# yum install yum-utils [root@docker ~]# yum-config-manager --add-repo https://openresty.org/package/centos/openresty.repo [root@docker ~]# yum install openresty [root@docker ~]# yum install openresty-resty

系统默认安装在/usr/local/openresty/目录下,版本如下

[root@docker openresty]# cd /usr/local/openresty/bin/ [root@docker bin]# ./openresty -v nginx version: openresty/1.13.6.2

可以将OpenResty目录加到PATH里，方便使用.

修改nginx.conf文件测试是否安装成功

tee /usr/local/openresty/nginx/conf/nginx.conf <<-'EOF' worker_processes 1; error_log logs/error.log; events { worker_connections 1024; } http { server { listen 8080; location / { default_type text/html; content_by_lua ' ngx.say("<p>hello, world</p>") '; } } } EOF [root@docker conf]# openresty -s reload [root@docker conf]# curl localhost:8080 <p>hello, world</p>

安装JWT模块

这里使用JWT官方推荐Lua实现库,项目地址为https://github.com/SkyLothar/...,有趣的是,这个项目的介绍是这么写的JWT For The Great Openresty,看来是为OpenResty量身定做.github上有安装教程,但一方面有些第三方库的安装文档没有提及,另一方面有些内容没有用到安装的时候可以跳过,这里将完整安装步骤重新整理了下.

1. 在release页面https://github.com/SkyLothar/...下载项目源码,截止到目前最新版为v0.1.11
2. 下载hmac源码,截止到目前项目还未release,只能下载项目里的源文件https://github.com/jkeys089/l...
3. 在服务器创建目录/usr/local/openresty/nginx/jwt-lua/resty,将第1步压缩包中目录lua-resty-jwt-0.1.11/lib/resty/下的所有lua文件和第2步中的hmac.lua文件拷贝到该目录下,文件列表如下.

[root@docker resty]# pwd /usr/local/openresty/nginx/jwt-lua/resty [root@docker resty]# ll total 60 -rwxr-xr-x. 1 root root 11592 Jul 18 10:40 evp.lua -rw-r--r--. 1 root root 3796 Jul 18 10:40 hmac.lua -rwxr-xr-x. 1 root root 27222 Jul 18 10:40 jwt.lua -rwxr-xr-x. 1 root root 15257 Jul 18 10:40 jwt-validators.lua

修改nginx.conf验证是否生效

tee /usr/local/openresty/nginx/conf/nginx.conf <<-'EOF' worker_processes 1; error_log logs/error.log info; events { worker_connections 1024; } http { lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;"; server { listen 8080; default_type text/plain; location = / { content_by_lua ' local cjson = require "cjson" local jwt = require "resty.jwt" local jwt_token = "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9" .. ".eyJmb28iOiJiYXIifQ" .. ".VAoRL1IU0nOguxURF2ZcKR0SGKE1gCbqwyh8u2MLAyY" local jwt_obj = jwt:verify("lua-resty-jwt", jwt_token) ngx.say(cjson.encode(jwt_obj)) '; } location = /sign { content_by_lua ' local cjson = require "cjson" local jwt = require "resty.jwt" local jwt_token = jwt:sign( "lua-resty-jwt", { header={typ="JWT", alg="HS256"}, payload={foo="bar"} } ) ngx.say(jwt_token) '; } } } EOF

[root@docker resty]# curl localhost:8080 {"signature":"VAoRL1IU0nOguxURF2ZcKR0SGKE1gCbqwyh8u2MLAyY","reason":"everything is awesome~ :p","valid":true,"raw_header":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9","payload":{"foo":"bar"},"header":{"alg":"HS256","typ":"JWT"},"verified":true,"raw_payload":"eyJmb28iOiJiYXIifQ"}

验证通过,jwt模块安装完毕

自定义验证逻辑

上面jwt模块还无法用于生产环境,有几个问题没解决

1. jwt token目前是写死在配置文件里,生产需要从header Authorization中获取
2. 验证失败目前返回是200生产需要返回401
3. 需要配置反向代理并且将用户信息放在代理header上

创建文件/usr/local/openresty/nginx/jwt-lua/resty/nginx-jwt.lua

local jwt = require "resty.jwt" local cjson = require "cjson" --your secret local secret = "5pil6aOO5YaN576O5Lmf5q+U5LiN5LiK5bCP6ZuF55qE56yR" local M = {} function M.auth(claim_specs) -- require Authorization request header local auth_header = ngx.var.http_Authorization if auth_header == nil then ngx.log(ngx.WARN, "No Authorization header") ngx.exit(ngx.HTTP_UNAUTHORIZED) end ngx.log(ngx.INFO, "Authorization: " .. auth_header) -- require Bearer token local _, _, token = string.find(auth_header, "Bearer%s+(.+)") if token == nil then ngx.log(ngx.WARN, "Missing token") ngx.exit(ngx.HTTP_UNAUTHORIZED) end ngx.log(ngx.INFO, "Token: " .. token) local jwt_obj = jwt:verify(secret, token) if jwt_obj.verified == false then ngx.log(ngx.WARN, "Invalid token: ".. jwt_obj.reason) ngx.exit(ngx.HTTP_UNAUTHORIZED) end ngx.log(ngx.INFO, "JWT: " .. cjson.encode(jwt_obj)) -- write the uid variable ngx.var.uid = jwt_obj.payload.sub end return M

修改配置文件nginx.conf

worker_processes 1; error_log logs/error.log info; events { worker_connections 1024; } http { upstream tomcat{ server localhost:80; } lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;"; server { listen 8080; set $uid ''; location / { access_by_lua ' local jwt = require("resty.nginx-jwt") jwt.auth() '; default_type application/json; proxy_set_header uid $uid; proxy_pass http://tomcat; } } }

这里后台启动了一台tomcat并设置监听端口为80,tomcat上部署了一个示例的war包,代码逻辑较简单,就是输出所有的header,代码如下:

package asan.demo; import java.io.IOException; import java.io.PrintWriter; import java.util.Enumeration; import javax.servlet.*; import javax.servlet.http.*; public class JWTDemoService extends HttpServlet { private static final String CONTENT_TYPE = "text/html; charset=UTF-8"; public void init(ServletConfig config) throws ServletException { super.init(config); } public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType(CONTENT_TYPE); PrintWriter out = response.getWriter(); Enumeration em=request.getHeaderNames(); while(em.hasMoreElements()){ String key=(String)em.nextElement(); String value=(String)request.getHeaders(key).nextElement(); out.println(String.format("%s ==> %s", key,value)); } out.close(); } }

重启OpenResty测试,如果没有指定jwt token信息返回401

[root@docker conf]# curl http://localhost:8080/jwtdemo/service <html> <head><title>401 Authorization Required</title></head> <body bgcolor="white"> <center><h1>401 Authorization Required</h1></center> <hr><center>openresty/1.13.6.2</center> </body> </html>

指定jwt token

[root@docker conf]# curl -i http://localhost:8080/jwtdemo/ -H 'Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODkyNzE3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkyODcxN30.W5UXlwKHSrpUAYbfoF-fTBTS9Enm1wsvCKNQm0yLSfQ' HTTP/1.1 200 Server: openresty/1.13.6.2 Date: Wed, 18 Jul 2018 05:52:13 GMT Content-Type: text/html;charset=UTF-8 Content-Length: 298 Connection: keep-alive uid ==> yaya host ==> tomcat connection ==> close user-agent ==> curl/7.29.0 accept ==> */* authorization ==> Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODkyNzE3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkyODcxN30.W5UXlwKHSrpUAYbfoF-fTBTS9Enm1wsvCKNQm0yLSfQ

从结果上看,后台服务已经获取到uid这个header
至于请求用到jwt token可以从任意平台生成只要保证secret一样即可,根据官网介绍,该库目前支持到jwt生成算法如图:

uuid生成

为每个请求生成唯一的uuid码可以将网关层上的请求和应用层的请求关联起来,对排查问题,接口统计都非常有用.

创建文件/usr/local/openresty/nginx/jwt-lua/resty/uuid.lua

local M = {} local charset = {} do -- [0-9a-zA-Z] for c = 48, 57 do table.insert(charset, string.char(c)) end for c = 65, 90 do table.insert(charset, string.char(c)) end for c = 97, 122 do table.insert(charset, string.char(c)) end end function M.uuid(length) local res = "" for i = 1, length do res = res .. charset[math.random(1, #charset)] end return res end return M

修改配置文件nginx.conf

worker_processes 1; error_log logs/error.log info; events { worker_connections 1024; } http { upstream tomcat{ server localhost:80; } lua_package_path "/usr/local/openresty/nginx/jwt-lua/?.lua;;"; server { listen 8080; set $uid ''; set $uuid ''; location / { access_by_lua ' local jwt = require("resty.nginx-jwt") jwt.auth() local u = require("resty.uuid") ngx.var.uuid = u.uuid(64) '; default_type application/json; proxy_set_header uid $uid; proxy_set_header uuid $uuid; proxy_pass http://tomcat; } } }

重启OpenResty,测试

[root@docker conf]# openresty -s reload [root@docker conf]# curl -i http://localhost:8080/jwtdemo/ -H 'Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODk0MDA3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkzMDAwN30.vQvpQpIHCmK5QBgIoRR8jhIGeYlHOMYySIr4gHvoZFE' HTTP/1.1 200 Server: openresty/1.13.6.2 Date: Wed, 18 Jul 2018 08:05:45 GMT Content-Type: text/html;charset=UTF-8 Content-Length: 372 Connection: keep-alive uid ==> yaya uuid ==> nhak5eLjQZ73yhAyHLTgZnSBeDa8pa1p3pcpBFvJ4Mv1fkY782UgVr8Islheq03l host ==> tomcat connection ==> close user-agent ==> curl/7.29.0 accept ==> */* authorization ==> Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJqdGkiOiJ5YXlhIiwiaWF0IjoxNTMxODk0MDA3LCJpc3MiOiJ5YXlhIiwic3ViIjoieWF5YSIsImV4cCI6MTUzMTkzMDAwN30.vQvpQpIHCmK5QBgIoRR8jhIGeYlHOMYySIr4gHvoZFE

可以看到,多了一个uuid的请求头

jwt token生成java示例

这里提供一个生成jwt token的java示例

package com.yaya; import io.jsonwebtoken.JwtBuilder; import io.jsonwebtoken.Jwts; import io.jsonwebtoken.SignatureAlgorithm; import javax.crypto.spec.SecretKeySpec; import java.security.Key; import java.util.Date; import java.util.HashMap; import java.util.Map; /** * @Description: * @author: jianfeng.zheng * @since: 2018/7/5 下午9:56 * @history: 1.2018/7/5 created by jianfeng.zheng */ public class JWTDemo { public static final String SECRET="5pil6aOO5YaN576O5Lmf5q+U5LiN5LiK5bCP6ZuF55qE56yR"; public static String createJWT(String uid, long ttlMillis) throws Exception { SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256; long nowMillis = System.currentTimeMillis(); Date now = new Date(nowMillis); Key signingKey = new SecretKeySpec(SECRET.getBytes(), signatureAlgorithm.getJcaName()); Map<String,Object> header=new HashMap<String,Object>(); header.put("typ","JWT"); header.put("alg","HS256"); JwtBuilder builder = Jwts.builder().setId(uid) .setIssuedAt(now) .setIssuer(uid) .setSubject(uid) .setHeader(header) .signWith(signatureAlgorithm, signingKey); if (ttlMillis >= 0) { long expMillis = nowMillis + ttlMillis; Date exp = new Date(expMillis); builder.setExpiration(exp); } return builder.compact(); } public static void main(String[]cmd) throws Exception { String s=createJWT("yaya",36000000); System.out.println("Bearer "+s); } }

pom.xml

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.yaya</groupId> <artifactId>jwtdemo</artifactId> <version>1.0-SNAPSHOT</version> <dependencies> <dependency> <groupId>io.jsonwebtoken</groupId> <artifactId>jjwt</artifactId> <version>0.6.0</version> </dependency> </dependencies> </project>

写在最后

这里只是解决了文章开头提到的第一个问题,接口需要知道是谁调用了接口,第二个问题,用户能不能调接口目前考虑用aop在应用层实现,后续也会继续更新.