CreateAccess - AWS Transfer Family

CreateAccess

Used by administrators to choose which groups in the directory should have access to upload and download files over the enabled protocols using AWS Transfer Family. For example, a Microsoft Active Directory might contain 50,000 users, but only a small fraction might need the ability to transfer files to the server. An administrator can use CreateAccess to limit the access to the correct set of users who need this ability.

Request Syntax

{ "ExternalId": "string", "HomeDirectory": "string", "HomeDirectoryMappings": [ { "Entry": "string", "Target": "string" } ], "HomeDirectoryType": "string", "Policy": "string", "PosixProfile": { "Gid": number, "SecondaryGids": [ number ], "Uid": number }, "Role": "string", "ServerId": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.

ExternalId

A unique identifier that is required to identify specific groups within your directory. The users of the group that you associate have access to your Amazon S3 or Amazon EFS resources over the enabled protocols using AWS Transfer Family. If you know the group name, you can view the SID values by running the following command using Windows PowerShell.

Get-ADGroup -Filter {samAccountName -like "YourGroupName*"} -Properties * | Select SamAccountName,ObjectSid

In that command, replace YourGroupName with the name of your Active Directory group.

The regex used to validate this parameter is a string of characters consisting of uppercase and lowercase alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@:/-

Type: String

Length Constraints: Minimum length of 1. Maximum length of 256.

Pattern: ^S-1-[\d-]+$

Required: Yes

HomeDirectory

The landing directory (folder) for a user when they log in to the server using the client.

A HomeDirectory example is /bucket_name/home/mydirectory.

Type: String

Length Constraints: Maximum length of 1024.

Pattern: ^$|/.*

Required: No

HomeDirectoryMappings

Logical directory mappings that specify what Amazon S3 or Amazon EFS paths and keys should be visible to your user and how you want to make them visible. You must specify the Entry and Target pair, where Entry shows how the path is made visible and Target is the actual Amazon S3 or Amazon EFS path. If you only specify a target, it is displayed as is. You also must ensure that your AWS Identity and Access Management (IAM) role provides access to paths in Target. This value can only be set when HomeDirectoryType is set to LOGICAL.

The following is an Entry and Target pair example.

[ { "Entry": "your-personal-report.pdf", "Target": "/bucket3/customized-reports/${transfer:UserName}.pdf" } ]

In most cases, you can use this value instead of the scope-down policy to lock down your user to the designated home directory ("chroot"). To do this, you can set Entry to / and set Target to the HomeDirectory parameter value.

The following is an Entry and Target pair example for chroot.

[ { "Entry:": "/", "Target": "/bucket_name/home/mydirectory" } ]

Note

If the target of a logical directory entry does not exist in Amazon S3 or EFS, the entry is ignored. As a workaround, you can use the Amazon S3 API or EFS API to create 0 byte objects as place holders for your directory. If using the CLI, use the s3api or efsapi call instead of s3 or efs so you can use the put-object operation. For example, you use the following: aws s3api put-object --bucket bucketname --key path/to/folder/. Make sure that the end of the key name ends in a / for it to be considered a folder.

Type: Array of HomeDirectoryMapEntry objects

Array Members: Minimum number of 1 item. Maximum number of 50 items.

Required: No

HomeDirectoryType

The type of landing directory (folder) you want your users' home directory to be when they log into the server. If you set it to PATH, the user will see the absolute Amazon S3 bucket or EFS paths as is in their file transfer protocol clients. If you set it LOGICAL, you will need to provide mappings in the HomeDirectoryMappings for how you want to make Amazon S3 or EFS paths visible to your users.

Type: String

Valid Values: PATH | LOGICAL

Required: No

Policy

A scope-down policy for your user so that you can use the same IAM role across multiple users. This policy scopes down user access to portions of their Amazon S3 bucket. Variables that you can use inside this policy include ${Transfer:UserName}, ${Transfer:HomeDirectory}, and ${Transfer:HomeBucket}.

Note

This only applies when domain of ServerId is S3. Amazon EFS does not use scope-down policies.

For scope-down policies, AWS Transfer Family stores the policy as a JSON blob, instead of the Amazon Resource Name (ARN) of the policy. You save the policy as a JSON blob and pass it in the Policy argument.

For an example of a scope-down policy, see Example scope-down policy.

For more information, see AssumeRole in the AWS Security Token Service API Reference.

Type: String

Length Constraints: Maximum length of 2048.

Required: No

PosixProfile

The full POSIX identity, including user ID (Uid), group ID (Gid), and any secondary groups IDs (SecondaryGids), that controls your users' access to your Amazon EFS file systems. The POSIX permissions that are set on files and directories in your file system determine the level of access your users get when transferring files into and out of your Amazon EFS file systems.

Type: PosixProfile object

Required: No

Role

Specifies the Amazon Resource Name (ARN) of the IAM role that controls your users' access to your Amazon S3 bucket or EFS file system. The policies attached to this role determine the level of access that you want to provide your users when transferring files into and out of your Amazon S3 bucket or EFS file system. The IAM role should also contain a trust relationship that allows the server to access your resources when servicing your users' transfer requests.

Type: String

Length Constraints: Minimum length of 20. Maximum length of 2048.

Pattern: arn:.*role/.*

Required: Yes

ServerId

A system-assigned unique identifier for a server instance. This is the specific server that you added your user to.

Type: String

Length Constraints: Fixed length of 19.

Pattern: ^s-([0-9a-f]{17})$

Required: Yes

Response Syntax

{ "ExternalId": "string", "ServerId": "string" }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

ExternalId

The external ID of the group whose users have access to your Amazon S3 or Amazon EFS resources over the enabled protocols using AWS Transfer Family.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 256.

Pattern: ^S-1-[\d-]+$

ServerId

The ID of the server that the user is attached to.

Type: String

Length Constraints: Fixed length of 19.

Pattern: ^s-([0-9a-f]{17})$

Errors

For information about the errors that are common to all actions, see Common Errors.

InternalServiceError

This exception is thrown when an error occurs in the AWSTransfer Family service.

HTTP Status Code: 500

InvalidRequestException

This exception is thrown when the client submits a malformed request.

HTTP Status Code: 400

ResourceExistsException

The requested resource does not exist.

HTTP Status Code: 400

ResourceNotFoundException

This exception is thrown when a resource is not found by the AWSTransfer Family service.

HTTP Status Code: 400

ServiceUnavailableException

The request has failed because the AWSTransfer Family service is not available.

HTTP Status Code: 500

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: