通配符 (*) 是否可以在 dynamodb 的细粒度访问策略中使用

Question

我有一个Amazon dynamodb表，其分区键由用户的ID（来自Facebook或Google）和其他字符组成。我知道通配符可用于指定细粒度访问策略的属性，但我无法让dynamodb:LeadingKeys中的通配符正常工作。

以下是工作策略：

{
  "Version": "2012-10-17",
  "Statement": [
      {
          "Effect": "Allow",
          "Action": [
              "dynamodb:BatchGetItem",
              "dynamodb:BatchWriteItem",
              "dynamodb:DeleteItem",
              "dynamodb:GetItem",
              "dynamodb:PutItem",
              "dynamodb:Query",
              "dynamodb:UpdateItem"
          ],
          "Resource": [
              "arn:aws:dynamodb:<region>:<...>:table/<table-name>"
          ],
          "Condition": {
              "ForAllValues:StringEquals": {
                  "dynamodb:LeadingKeys": [
                      "g_${accounts.google.com:sub}"
                  ]
              }
          }
      }
  ]
}

但是，这不起作用：

{
  "Version": "2012-10-17",
  "Statement": [
      {
          "Effect": "Allow",
          "Action": [
              "dynamodb:BatchGetItem",
              "dynamodb:BatchWriteItem",
              "dynamodb:DeleteItem",
              "dynamodb:GetItem",
              "dynamodb:PutItem",
              "dynamodb:Query",
              "dynamodb:UpdateItem"
          ],
          "Resource": [
              "arn:aws:dynamodb:<region>:<...>:table/<table-name>"
          ],
          "Condition": {
              "ForAllValues:StringEquals": {
                  "dynamodb:LeadingKeys": [
                      "*_${accounts.google.com:sub}"
                  ]
              }
          }
      }
  ]
}

Answer 1

我找到了解决这个问题的方法。因此，与其使用ForAllValues:StringEquals，不如使用ForAllValues:StringLike。

工作方针是这样的：

{
  "Version": "2012-10-17",
  "Statement": [
      {
          "Effect": "Allow",
          "Action": [
              "dynamodb:BatchGetItem",
              "dynamodb:BatchWriteItem",
              "dynamodb:DeleteItem",
              "dynamodb:GetItem",
              "dynamodb:PutItem",
              "dynamodb:Query",
              "dynamodb:UpdateItem"
          ],
          "Resource": [
              "arn:aws:dynamodb:<region>:<...>:table/<table-name>"
          ],
          "Condition": {
              "ForAllValues:StringLike": {
                  "dynamodb:LeadingKeys": [
                      "*_${accounts.google.com:sub}"
                  ]
              }
          }
      }
  ]
}

我花了一段时间才找到这个参考：http://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements.html#AccessPolicyLanguage_ConditionType