AWS::Logs::AccountPolicy - AWS CloudFormation

AWS::Logs::AccountPolicy

Creates or updates an account-level data protection policy or subscription filter policy that applies to all log groups or a subset of log groups in the account.

Data protection policy

A data protection policy can help safeguard sensitive data that's ingested by your log groups by auditing and masking the sensitive log data. Each account can have only one account-level data protection policy.

Important

Sensitive data is detected and masked when it is ingested into a log group. When you set a data protection policy, log events ingested into the log groups before that time are not masked.

If you create a data protection policy for your whole account, it applies to both existing log groups and all log groups that are created later in this account. The account policy is applied to existing log groups with eventual consistency. It might take up to 5 minutes before sensitive data in existing log groups begins to be masked.

By default, when a user views a log event that includes masked data, the sensitive data is replaced by asterisks. A user who has the logs:Unmask permission can use a GetLogEvents or FilterLogEvents operation with the unmask parameter set to true to view the unmasked log events. Users with the logs:Unmask can also view unmasked data in the CloudWatch Logs console by running a CloudWatch Logs Insights query with the unmask query command.

For more information, including a list of types of data that can be audited and masked, see Protect sensitive log data with masking.

To create an account-level policy, you must be signed on with the logs:PutDataProtectionPolicy and logs:PutAccountPolicy permissions.

An account-level policy applies to all log groups in the account. You can also create a data protection policy that applies to just one log group. If a log group has its own data protection policy and the account also has an account-level data protection policy, then the two policies are cumulative. Any sensitive term specified in either policy is masked.

Subscription filter policy

A subscription filter policy sets up a real-time feed of log events from CloudWatch Logs to other AWS services. Account-level subscription filter policies apply to both existing log groups and log groups that are created later in this account. Supported destinations are Kinesis Data Streams, Firehose, and Lambda. When log events are sent to the receiving service, they are Base64 encoded and compressed with the GZIP format.

The following destinations are supported for subscription filters:

  • An Kinesis Data Streams data stream in the same account as the subscription policy, for same-account delivery.

  • An Firehose data stream in the same account as the subscription policy, for same-account delivery.

  • A Lambda function in the same account as the subscription policy, for same-account delivery.

  • A logical destination in a different account created with PutDestination, for cross-account delivery. Kinesis Data Streams and Firehose are supported as logical destinations.

Each account can have one account-level subscription filter policy. If you are updating an existing filter, you must specify the correct name in PolicyName. To perform a PutAccountPolicy subscription filter operation for any destination except a Lambda function, you must also have the iam:PassRole permission.

Syntax

To declare this entity in your AWS CloudFormation template, use the following syntax:

JSON

{ "Type" : "AWS::Logs::AccountPolicy", "Properties" : { "PolicyDocument" : String, "PolicyName" : String, "PolicyType" : String, "Scope" : String, "SelectionCriteria" : String } }

YAML

Type: AWS::Logs::AccountPolicy Properties: PolicyDocument: String PolicyName: String PolicyType: String Scope: String SelectionCriteria: String

Properties

PolicyDocument

Specify the policy, in JSON.

Data protection policy

A data protection policy must include two JSON blocks:

  • The first block must include both a DataIdentifer array and an Operation property with an Audit action. The DataIdentifer array lists the types of sensitive data that you want to mask. For more information about the available options, see Types of data that you can mask.

    The Operation property with an Audit action is required to find the sensitive data terms. This Audit action must contain a FindingsDestination object. You can optionally use that FindingsDestination object to list one or more destinations to send audit findings to. If you specify destinations such as log groups, Firehose streams, and S3 buckets, they must already exist.

  • The second block must include both a DataIdentifer array and an Operation property with an Deidentify action. The DataIdentifer array must exactly match the DataIdentifer array in the first block of the policy.

    The Operation property with the Deidentify action is what actually masks the data, and it must contain the "MaskConfig": {} object. The "MaskConfig": {} object must be empty.

Important

The contents of the two DataIdentifer arrays must match exactly.

In addition to the two JSON blocks, the policyDocument can also include Name, Description, and Version fields. The Name is different than the operation's policyName parameter, and is used as a dimension when CloudWatch Logs reports audit findings metrics to CloudWatch.

The JSON specified in policyDocument can be up to 30,720 characters long.

Subscription filter policy

A subscription filter policy can include the following attributes in a JSON block:

  • DestinationArn The ARN of the destination to deliver log events to. Supported destinations are:

    • An Kinesis Data Streams data stream in the same account as the subscription policy, for same-account delivery.

    • An Firehose data stream in the same account as the subscription policy, for same-account delivery.

    • A Lambda function in the same account as the subscription policy, for same-account delivery.

    • A logical destination in a different account created with PutDestination, for cross-account delivery. Kinesis Data Streams and Firehose are supported as logical destinations.

  • RoleArn The ARN of an IAM role that grants CloudWatch Logs permissions to deliver ingested log events to the destination stream. You don't need to provide the ARN when you are working with a logical destination for cross-account delivery.

  • FilterPattern A filter pattern for subscribing to a filtered stream of log events.

  • DistributionThe method used to distribute log data to the destination. By default, log data is grouped by log stream, but the grouping can be set to Random for a more even distribution. This property is only applicable when the destination is an Kinesis Data Streams data stream.

Required: Yes

Type: String

Minimum: 1

Maximum: 30720

Update requires: No interruption

PolicyName

A name for the policy. This must be unique within the account.

Required: Yes

Type: String

Pattern: ^[^:*]{1,256}$

Minimum: 1

Maximum: 256

Update requires: Replacement

PolicyType

The type of policy that you're creating or updating.

Required: Yes

Type: String

Allowed values: DATA_PROTECTION_POLICY | SUBSCRIPTION_FILTER_POLICY

Update requires: Replacement

Scope

Currently the only valid value for this parameter is ALL, which specifies that the policy applies to all log groups in the account. If you omit this parameter, the default of ALL is used. To scope down a subscription filter policy to a subset of log groups, use the selectionCriteria parameter.

Required: No

Type: String

Allowed values: ALL

Update requires: No interruption

SelectionCriteria

Use this parameter to apply a subscription filter policy to a subset of log groups in the account. Currently, the only supported filter is LogGroupName NOT IN []. The selectionCriteria string can be up to 25KB in length. The length is determined by using its UTF-8 bytes.

Using the selectionCriteria parameter is useful to help prevent infinite loops. For more information, see Log recursion prevention.

Specifing selectionCriteria is valid only when you specify SUBSCRIPTION_FILTER_POLICY for policyType.

Required: No

Type: String

Update requires: No interruption

Return values

Fn::GetAtt

The Fn::GetAtt intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.

For more information about using the Fn::GetAtt intrinsic function, see Fn::GetAtt.

AccountId

The account ID of the account where this policy was created. For example, 123456789012.

Examples

Create an account-level data protection policy

The following example creates an account-level data protection policy that finds and masks email addresses in log events. It also sends audit findings to the EXISTING_LOG_GROUP_NAME log group in CloudWatch Logs.

JSON

{ "Resources": { "AccountPolicy": { "Type": "AWS::Logs::AccountPolicy", "Properties": { "PolicyName": "TestPolicy", "PolicyDocument": "{ \"Name\": \"data-protection-policy\", \"Description\": \"\", \"Version\": \"2021-06-01\", \"Statement\": [ { \"Sid\": \"audit-policy\", \"DataIdentifier\": [ \"arn:aws:dataprotection::aws:data-identifier/EmailAddress\" ], \"Operation\": { \"Audit\": { \"FindingsDestination\": { \"CloudWatchLogs\": { \"LogGroup\": \"EXISTING_LOG_GROUP_NAME\" } } } } }, { \"Sid\": \"redact-policy\", \"DataIdentifier\": [ \"arn:aws:dataprotection::aws:data-identifier/EmailAddress\" ], \"Operation\": { \"Deidentify\": { \"MaskConfig\": {} } } } ] }", "PolicyType": "DATA_PROTECTION_POLICY", "Scope": "ALL" } } } }

YAML

Resources: AccountPolicy: Type: AWS::Logs::AccountPolicy Properties: PolicyName: "TestPolicy" PolicyDocument: '{ "Name": "data-protection-policy", "Description": "", "Version": "2021-06-01", "Statement": [ { "Sid": "audit-policy", "DataIdentifier": [ "arn:aws:dataprotection::aws:data-identifier/EmailAddress" ], "Operation": { "Audit": { "FindingsDestination": { "CloudWatchLogs": { "LogGroup": "EXISTING_LOG_GROUP_NAME" } } } } }, { "Sid": "redact-policy", "DataIdentifier": [ "arn:aws:dataprotection::aws:data-identifier/EmailAddress" ], "Operation": { "Deidentify": { "MaskConfig": {} } } } ] }' PolicyType: "DATA_PROTECTION_POLICY" Scope: "ALL"

Create an account-level subscription filter policy

The following example creates an account-level subscription filter policy that forwards the log events matching the FilterPattern from all the log groups in an account to the specified ak Kinesis Data Streams stream. It forwards the log events from all the log groups except the ones that are specified in the SelectionCriteria field.

JSON

{ "Resources": { "AccountPolicy": { "Type": "AWS::Logs::AccountPolicy", "Properties": { "PolicyName": "test-subscriptionfilter-policy", "PolicyDocument": { "Fn::Sub": "{\"RoleArn\":\"arn:${AWS::Partition}:iam::${AWS::AccountId}:role/MyCWLtoKinesisRole\", \"DestinationArn\":\"arn:${AWS::Partition}:kinesis:${AWS::Region}:${AWS::AccountId}:stream/MyKinesisStream\", \"FilterPattern\": \"Test\", \"Distribution\": \"Random\"}" }, "SelectionCriteria": { "Fn::Sub": "LogGroupName NOT IN [\"MyLogGroup\", \"MyAnotherLogGroup\"]" }, "PolicyType": "SUBSCRIPTION_FILTER_POLICY", "Scope": "ALL" } } } }

YAML

Resources: AccountPolicy: Type: AWS::Logs::AccountPolicy Properties: PolicyName: test-subscriptionfilter-policy PolicyDocument: !Sub "{\"RoleArn\":\"arn:${AWS::Partition}:iam::${AWS::AccountId}:role/MyCWLtoKinesisRole\", \"DestinationArn\":\"arn:${AWS::Partition}:kinesis:${AWS::Region}:${AWS::AccountId}:stream/MyKinesisStream\", \"FilterPattern\": \"Test\", \"Distribution\": \"Random\"}" SelectionCriteria: !Sub "LogGroupName NOT IN [\"MyLogGroup\", \"MyAnotherLogGroup\"]" PolicyType: "SUBSCRIPTION_FILTER_POLICY" Scope: "ALL"