ballerina 学习三十二编写安全的程序

ballerina编译器已经集成了部分安全检测，在编译时可以帮助我们生成错误提示，同时ballerina 标准库
已经对于常见漏洞高发的地方做了很好的处理，当我们编写了有安全隐患的代码，编译器就已经提示给
我们了。
常见的问题

sql 注入
path 操作
file 操作
未授权文件访问
为校验的重定向

确保ballerina 标准库的安全

ballerina 标准库对于安全敏感的函数以及操作使用@sensitive 注解进行说明，可以确保容易出现漏洞的数据传递
给参数
比如,ballerina 标准库的select

public native function select(@sensitive string sqlQuery, typedesc? recordType,boolean loadToMemory = false, Param... parameters)returns @tainted table|error;

安全的使用不可信数据

实际中我们肯定会碰到需要传递非可信数据，我们可以使用 untaint 表达式进行处理，同时对于返回值我们可以使用
@untainted 注解
参考

boolean isValid = isNumeric(studentId);
if (isValid) {var dt = testDB->select("SELECT NAME FROM STUDENT WHERE ID = " +untaint studentId, ResultStudent);
}function sanitizeSortColumn (string columnName) returns @untainted string {string sanitizedSortColumn = columnName;// Sanitize logic to make sure return value is safereturn sanitizedSortColumn;
}

保护密码以及secret key

ballerina 提供了api 可以访问不同源的配置信息，对于配置文件中包含密码信息的必须加密
处理，框架提供了工具可以对于配置进行加密

ballerina encrypt
按照提示输入需要加密的名称，会生成一个加密key，我们可以使用配置文件，或者环境变量获取。
默认会找一个secret.txt的文件，里面存储了加密密钥，请求之后会自动删除，对于没有这个文件的
会提示输入密钥

认证&&授权

ballerina 的 http 服务可以配置的方式增强认证以及授权，ballerina 支持jwt 以及basic 模式的认证，
使用basic模式时，用户信息可以通过配置文件加载，同时推荐使用https 方式进行数据访问，增强
安全性

jwt 认证
可以通过http:AuthProvider 进行配置
参考

import ballerina/http;http:AuthProvider jwtAuthProvider = {scheme:"jwt",issuer:"ballerina",audience: "ballerina.io",clockSkew:10,certificateAlias: "ballerina",trustStore: {path: "${ballerina.home}/bre/security/ballerinaTruststore.p12",password: "ballerina"}
};endpoint http:SecureListener secureHelloWorldEp {port:9091,authProviders:[jwtAuthProvider],secureSocket: {keyStore: {path: "${ballerina.home}/bre/security/ballerinaKeystore.p12",password: "ballerina"}}
};@http:ServiceConfig {basePath:"/hello"
}
service<http:Service> helloWorld bind secureHelloWorldEp {@http:ResourceConfig {methods:["GET"],path:"/"}sayHello (endpoint caller, http:Request req) {http:Response resp = new;resp.setTextPayload("Hello, World!");_ = caller->respond(resp);}
}

http basic 认证
参考代码

import ballerina/http;http:AuthProvider basicAuthProvider = {scheme:"basic",authStoreProvider:"config"
};endpoint http:SecureListener secureHelloWorldEp {port:9091,authProviders:[basicAuthProvider],secureSocket: {keyStore: {path: "${ballerina.home}/bre/security/ballerinaKeystore.p12",password: "ballerina"}}
};@http:ServiceConfig {basePath:"/hello",authConfig:{scopes:["hello"]}
}
service<http:Service> helloWorld bind secureHelloWorldEp {@http:ResourceConfig {methods:["GET"],path:"/"}sayHello (endpoint caller, http:Request req) {http:Response resp = new;resp.setTextPayload("Hello, World!");_ = caller->respond(resp);}
}

用户账户配置信息(通过配置文件)

sample-users.toml["b7a.users"]["b7a.users.generalUser"]
password="@encrypted:{pIQrB9YfCQK1eIWH5d6UaZXA3zr+60JxSBcpa2PY7a8=}"["b7a.users.admin"]
password="@encrypted:{pIQrB9YfCQK1eIWH5d6UaZXA3zr+60JxSBcpa2PY7a8=}"
scopes="hello"

加载配置

ballerina run --config sample-users.toml basic_auth_sample.bal

说明
在认证服务的同时，我们可以配置scope，指定权限范围，还是比较方便的

下游服务的认证

实际上就是在client 端加载认证信息，方便调用

一个jwt client 的例子

import ballerina/http;http:AuthProvider jwtAuthProvider = {scheme:"jwt",propagateToken: true,issuer:"ballerina",audience: "ballerina.io",clockSkew:10,certificateAlias: "ballerina",trustStore: {path: "${ballerina.home}/bre/security/ballerinaTruststore.p12",password: "ballerina"}
};endpoint http:SecureListener secureHelloWorldEp {port:9091,authProviders:[jwtAuthProvider],secureSocket: {keyStore: {path: "${ballerina.home}/bre/security/ballerinaKeystore.p12",password: "ballerina"}}
};endpoint http:Client downstreamServiceEP {url: "https://localhost:9092",auth: { scheme: http:JWT_AUTH },secureSocket: {trustStore: {path: "${ballerina.home}/bre/security/ballerinaTruststore.p12",password: "ballerina"}}
};@http:ServiceConfig {basePath:"/hello",authConfig:{scopes:["hello"]}
}
service<http:Service> helloWorld bind secureHelloWorldEp {@http:ResourceConfig {methods:["GET"],path:"/"}sayHello (endpoint caller, http:Request req) {http:Response response = check downstreamServiceEP->get("/update-stats",message = untaint req);_ = caller->respond(response);}
}// ----------------------------------------------
// Following code creates the downstream service
// ----------------------------------------------http:AuthProvider downstreamJwtAuthProvider = {scheme:"jwt",issuer:"ballerina",audience: "ballerina.io",clockSkew:10,certificateAlias: "ballerina",trustStore: {path: "${ballerina.home}/bre/security/ballerinaTruststore.p12",password: "ballerina"}
};endpoint http:SecureListener secureUpdateServiceEp {port:9092,authProviders:[downstreamJwtAuthProvider],secureSocket: {keyStore: {path: "${ballerina.home}/bre/security/ballerinaKeystore.p12",password: "ballerina"}}
};@http:ServiceConfig {basePath:"/update-stats"
}
service<http:Service> updateService bind secureUpdateServiceEp {@http:ResourceConfig {methods:["GET"],path:"/"}updateStats (endpoint caller, http:Request req) {http:Response resp = new;resp.setTextPayload("Downstream Service Received JWT: " +untaint req.getHeader("Authorization"));_ = caller->respond(resp);}
}

说明

ballerina 的设计以及功能还是很方便的，功能很齐全。

参考资料

https://ballerina.io/learn/how-to-write-secure-ballerina-code/