aws-lambda - AWS IAM 执行角色无权在 EC2 上为特定 VPC 调用 CreateNetworkInterface

Question

我收到此错误:Error: Error creating Lambda function: InvalidParameterValueException: The provided execution role does not have permissions to call CreateNetworkInterface on EC2当尝试使用自定义 Lambda 角色创建具有 IAM 权限的 lambda 时，如下所示:

  ...
  statement {
    sid = "MyCustomLamdaStatementDescribe"
    actions = [
      "ec2:DescribeNetworkInterfaces",
    ]
    resources = ["*"]
  }
  statement {
    sid = "MyCustomLamdaStatementCreateDelete"
    actions = [
        "ec2:AttachNetworkInterface",
        "ec2:CreateNetworkInterface",
        "ec2:DeleteNetworkInterface",
        "ec2:AssignPrivateIpAddresses",
        "ec2:UnassignPrivateIpAddresses",
        "ec2:DescribeVpcs"
    ]
    resources = [
      "*"
    ]
    condition {
      test     = "ArnEquals"
      variable = "ec2:vpc"
      values = [
        "arn:aws:ec2:${var.my_region}:${var.my_account_id}:vpc/${var.my_vpc_id}",
      ]
    }
  }
  ...

创建 lambda 可以在没有任何条件的情况下完美运行(如 AWS Lambda:The provided execution role does not have permissions to call DescribeNetworkInterfaces on EC2 中指出的)，但我需要该角色能够匹配 VPC(或 ec2:Subnet arn)。

注意:我用ArnEquals尝试了condition.test和StringEquals .

Answer 1

如果您想将此限制为仅一个 VPC，则必须拆分每个操作。

ec2:DescribeNetworkInterfaces 只能与 Resource: * 一起使用且无条件(请参阅 docs )。但这本身是相对无害的。其他的可以限制。

这是一个采用 YAML (CloudFormation) 格式的解决方案。 它并不完美。 特别是，我不知道如何限制资源或对 ec2:DeleteNetworkInterface 应用条件。当我尝试时，我得到了同样的错误。

- Effect: Allow
  Action:
    - 'ec2:CreateNetworkInterface'
  Resource:
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:security-group/${SecGrp}'
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:subnet/${SubnetA}'
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:subnet/${SubnetB}'
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:subnet/${SubnetC}'
  Condition:
    StringEquals:
      'ec2:Vpc': !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:vpc/${VPC}'
- Effect: Allow
  Action:
    - 'ec2:CreateNetworkInterface'
  Resource:
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:network-interface/*'
    # VPC condition not supported for this type of resource for this action
- Effect: Allow
  Action:
    - 'ec2:DeleteNetworkInterface'
  Resource:
    # I don't know why we need the first
    # the docs say the second is sufficient, but it doesn't work
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:*'
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:network-interface/*'
  # the docs say this is supported, but it's not
  # Condition:
  #   StringEquals:
  #     'ec2:Vpc': !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:vpc/${VPC}'

- Effect: Allow
  Action:
    # this action must have resource: * and no conditions
    # cannot be restricted
    - 'ec2:DescribeNetworkInterfaces'
  Resource:
    - '*'
- Effect: Allow
  Action:
    - 'ec2:AssignPrivateIpAddresses'
    - 'ec2:UnassignPrivateIpAddresses'
  Resource:
    - !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:network-interface/*'

  Condition:
    StringEquals:
      'ec2:Vpc': !Sub 'arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:vpc/${VPC}'