阿里云STS token浅析
非常想搞明白STS token在端上是如何使用的。因为OSS跟STS联系比较紧密，所以把这两个家伙一起研究了一下。里面有一些环节我现在也没搞太明白，只是记录一下，以后搞明白了再完善。
配置账号及角色
去RAM里面设置好子账号和角色，子账号需要AliyunSTSAssumeRoleAccess权限，角色需要AliyunOSSFullAccess权限。子账号需要有扮演OSS存取这个角色的能力，成功扮演该角色之后，就具有操作OSS资源的能力了。关于用户和角色关系，RAM和STS介绍里面有比较详细的描述。
这里有一个坑是角色一定要选择用户角色。之前错误选择了服务角色，导致AssumeRole一直提示无权限。
screenshot.png
获取STS token
- 安装好Python SDK。Python测试起来比较方便。
pip install oss2
- 运行脚本，获取STS token。
#!/usr/bin/env python
#coding=utf-8
from aliyunsdkcore import client
from aliyunsdksts.request.v20150401 import AssumeRoleRequest
clt = client.AcsClient('access key id', 'access key secret', 'cn-shanghai')
# 构造"AssumeRole"请求
request = AssumeRoleRequest.AssumeRoleRequest()
# 指定角色
request.set_RoleArn('acs:ram::1532770894211314:role/henshaoread2')
# 设置会话名称，审计服务使用此名称区分调用者
request.set_RoleSessionName('henshao')
#request.set_method('HMAC-SHA1')
# 发起请求，并得到response
response = clt.do_action_with_exception(request)
实际发出来的请求如下所示。STS API和签名规则可以参考STS文档。
/?RoleSessionName=henshao
&Format=json
&Timestamp=2017-04-28T08%3A16%3A06Z
&RoleArn=acs%3Aram%3A%3A1532770894211314%3Arole%2Fhenshaoread2
&RegionId=cn-shanghai
&SignatureVersion=1.0
&AccessKeyId=LTAIAVqsmhvxNjGN
&SignatureMethod=HMAC-SHA1
&Version=2015-04-01
&Signature=9geUPq00G2g1tInX3XSvk77HZhY%3D
&Action=AssumeRole
&SignatureNonce=cc636798-de57-4c11-beb5-567124635220
- 返回的STS token如下所示，里面包含了AK id、AK secret）和security token。
screenshot.png
另外一种获取STS token的方式是使用aliyuncli工具，也是非常方便的。
$ aliyuncli sts AssumeRole --AccessKeyId xxx --AccessKeySecret xxx --RoleArn xxx --RoleSessionName xxx
{
"AssumedRoleUser": {
"AssumedRoleId": "389053493353396514:henshao",
"Arn": "acs:ram::1532770894211314:role/henshaoread2/henshao"
},
"Credentials": {
"AccessKeySecret": "4s7GoYW7bbFLqe3XGbiMdjveaHEvU1bNBNxdXPtkgLK2",
"SecurityToken": "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",
"Expiration": "2017-11-02T06:01:53Z",
"AccessKeyId": "STS.MFp1gtANya4MR9FhwNx4A8mb8"
},
"RequestId": "14AA9E4A-EEF0-403A-9367-3255E836F382"
}
OSS客户端使用STS token获取文件
拿到STS token，客户端上就可以操作OSS资源了。
id<OSSCredentialProvider> credential = [[OSSStsTokenCredentialProvider alloc] initWithAccessKeyId:@"STS.DSVjYCefVuXKNP9CTyCfy83Uf" secretKeyId:@"7raTtc4LK3ZtHrw8wWse7sbWAJypWdox3cpp5nYwxdDk" securityToken:@"CAIS8gF1q6Ft5B2yfSjIpZDjIeP3iLl3wpqgTHaIp1QsT+lV1/b+hDz2IHBFfHRrBeEdtfk0n2FW6/8elq5zRpleRUXDNSGpOWeEslHPWZHInuDox55m4cTXNAr+Ihr/29CoEIedZdjBe/CrRknZnytou9XTfimjWFrXWv/gy+QQDLItUxK/cCBNCfpPOwJms7V6D3bKMuu3OROY6Qi5TmgQ41cn0zwgsfTunpfFs0GH0GeXkLFF+97DRbG/dNRpMZtFVNO44fd7bKKp0lQLu0kSqfwq3fcfpGyc74/AWgVLhxWLNfHU+9p1IQZ1PLigomnpBFFI/xqAAU0Ia5eMa0XreO/Uh0K6RXJmk9q8dEKrhhMuDEtCK/EUyb+v/8WSfeYez3z2wl9V5Pi7iUSFRciQKHnGyIVAVmBCGWvAZOad83dI8tft8Ks16/mER/wpysTKOcr+rrdn+JnPJDSFDKD5JBJSr0KXR1bbMU+9b0Nrej0P8kVwbhYd"];
OSSClient *client = [[OSSClient alloc] initWithEndpoint:@"oss-cn-shanghai.aliyuncs.com" credentialProvider:credential];
OSSGetObjectRequest * request = [OSSGetObjectRequest new];
request.bucketName = @"wla-test2";
request.objectKey = @"DragonMedium.png";
request.downloadProgress = ^(int64_t bytesWritten, int64_t totalBytesWritten, int64_t totalBytesExpectedToWrite) {
NSLog(@"%lld, %lld, %lld", bytesWritten, totalBytesWritten, totalBytesExpectedToWrite);
};
OSSTask * getTask = [client getObject:request];
[getTask continueWithBlock:^id(OSSTask *task) {
if (!task.error) {
NSLog(@"download object success!");
OSSGetObjectResult * getResult = task.result;
NSLog(@"download result: %@", getResult.downloadedData);
UIImage *image = [[UIImage alloc] initWithData: getResult.downloadedData];
image = nil;
} else {
NSLog(@"download object failed, error: %@" ,task.error);
}
return nil;
}];
成功获取到DragonMedium.png这张图片。
screenshot.png
稍微分析了一下OSS SDK里面的细节。在header里面有两个重要的字段，Authorization = "OSS " + AK.Id + ":" + sign，x-oss-security-token则是security token。
(lldb) po requestMessage.headerParams
{
Authorization = "OSS STS.DSVjYCefVuXKNP9CTyCfy83Uf:spZmloXZZJZFBCE8st9fvRxKLag=";
"User-Agent" = "aliyun-sdk-ios/2.6.0/iOS/10.3/en_US";
"x-oss-security-token" = "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";
}
参考资料
最后非常感谢 @周卓 大神的鼎力支持?
