只需添加 KmsMasterKeyId

MyTopic:
  Type: AWS::SNS::Topic
  Properties:
    TopicName: MyTopic
    KmsMasterKeyId: 1234abcd-12ab-34cd-56ef-1234567890ab

来源：AWS Cloudformation document

如上述答案所建议，您将需要在SNS主题定义中引用KMS密钥。您可以为SNS使用默认的KMS密钥（别名aws/sns），也可以创建自己的

您可以在下面的CloudFormation中查看如何在同一模板中使用自己的KMS密钥创建加密主题和KMS密钥。密钥策略设置为允许通过整个AWS账户进行管理和使用，尽管您可能希望使用最低特权原则将其锁定，具体取决于您所处环境的安全要求。

---
AWSTemplateFormatVersion: '2010-09-09'
Description: Demo template for Encrypted SNS Topic

Resources:
  SNSKMSKey:
    Type: 'AWS::KMS::Key'
    Properties:
      Description: Demo KMS Key Policy
      Enabled: true
      EnableKeyRotation: true
      KeyPolicy:
        Version: 2012-10-17
        Id: KmsKeyPolicy
        Statement:
          - Sid: SimpleKeyPolicyAllowAccountAdmin
            Effect: Allow
            Principal:
              AWS: !Sub "arn:aws:iam::${AWS::AccountId}:root"
            Action:
              - 'kms:*'
            Resource: '*'
          - Sid: SimpleKeyPolicyAllowAccountUsage
            Effect: Allow
            Principal:
              AWS: !Sub "arn:aws:iam::${AWS::AccountId}:root"
            Action:
              - 'kms:Decrypt'
              - 'kms:Encrypt'
              - 'kms:GenerateDataKey*'
              - 'kms:DescribeKey'
            Resource: '*'


  SNSKmeKeyAlias:
    Type: "AWS::KMS::Alias"
    Properties:
      AliasName: !Sub "alias/${AWS::StackName}-SNSEncryptionKey"
      TargetKeyId: !Ref SNSKMSKey

  # -- Encrypted  SNS Topic -- #
  EncryptedSNSTopic:
    Type: AWS::SNS::Topic
    Properties:
      TopicName: !Sub "${AWS::StackName}-EncryptedSNSTopic"
      KmsMasterKeyId: !Ref SNSKMSKey


Outputs:
  KmsKeyId:
    Value: !Ref SNSKMSKey
  TopicArn:
    Value: !Ref EncryptedSNSTopic

如果您正在寻找带有默认KMS的简单SNS主题，则语法如下。我还添加了电子邮件订阅。您可以根据需要更改订阅：

  RedshiftNotificationTopicSNS:
    Type: AWS::SNS::Topic
    Properties:
      KmsMasterKeyId: alias/aws/sns
      Subscription:
        - Endpoint: !Ref NotificationEmailId
          Protocol: email