amazon-web-services - AWS Lambda S3 访问被拒绝

Question

我有一个使用具有以下策略摘录的角色的 lambda 函数

{
            "Effect": "Allow",
            "Action": [
                "s3:GetObject",
                "s3:ListBucket"
            ],
            "Resource": [
                "arn:aws:s3:::ipwl-lambda-config/*",
                "arn:aws:s3:::ipwl-lambda-config"
            ]
        }

我的存储桶策略如下所示

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "DenyUnEncryptedObjectUploads",
            "Effect": "Deny",
            "Principal": {
                "AWS": "*"
            },
            "Action": "s3:PutObject",
            "Resource": "arn:aws:s3:::ipwl-lambda-config/*",
            "Condition": {
                "StringNotEquals": {
                    "s3:x-amz-server-side-encryption": "aws:kms"
                }
            }
        },
        {
            "Sid": "AllowLambda",
            "Effect": "Allow",
            "Principal": {
                "AWS": "arn:aws:iam::accountid:role/iam_for_lambda"
            },
            "Action": [
                "s3:ListBucket",
                "s3:GetObject"
            ],
            "Resource": [
                "arn:aws:s3:::ipwl-lambda-config/*",
                "arn:aws:s3:::ipwl-lambda-config"
            ]
        }
    ]
}

我在角色和存储桶策略上都允许使用 GetObject 和 ListBucket。但是当我的函数运行时
s3_obj = s3_res.Object(s3_bucket, s3_object)
我得到

[ERROR] ClientError: An error occurred (AccessDenied) when calling the GetObject operation: Access Denied

我还需要添加哪些权限？对象在那里，当我使用管理员角色在本地运行代码时，我可以获得它。

更新

我已经检查了几十次以确保存储桶和对象名称是正确的。根据堆栈跟踪，异常实际上来自这里的第二行

s3_res = boto3.resource('s3')
s3_obj = s3_res.Object(s3_bucket, s3_object)
data = s3_obj.get()['Body'].read()

KMS 应该只是 PutObject 的一个因素。我们有一个支持帐户，因此我可以与他们核对并更新他们的发现。

Answer 1

要从 S3 下载 KMS 加密的对象，您不仅需要能够获取该对象。您还需要能够解密 AWS KMS key 。

以下是您的 Lambda 函数应具有的 IAM 策略示例:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "s3get",
      "Effect": "Allow",
      "Action": "s3:GetObject",
      "Resource": "arn:aws:s3:::ipwl-lambda-config/*"
    },
    {
      "Sid": "kmsdecrypt",
      "Effect": "Allow",
      "Action": "kms:Decrypt",
      "Resource": "arn:aws:kms:example-region-1:123456789012:key/example-key-id"
    }
  ]
}

key 策略还需要允许 IAM 角色解密 key ，如下所示:

{
  "Sid": "kmsdecrypt",
  "Effect": "Allow",
  "Principal": {
    "AWS": "arn:aws:iam::123456789012:role/xyz"
  },
  "Action": "kms:Decrypt",
  "Resource": "*"
}