AWS API Changes

2026/09/14 - AWS Security Token Service - 6 updated api methods

Changes Increases the maximum session token size to 4,096 bytes and removes the packed policy size limit. Adds SessionTokenSize and SessionTokenUtilization fields and a new MinimumSessionTokenSize parameter. PackedPolicySize is deprecated.

AssumeRole (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of temporary security credentials that you can use to access Amazon Web Services resources. These temporary credentials consist of an access key ID, a secret access key, and a security token. Typically, you use AssumeRole within your account or for cross-account access. For a comparison of AssumeRole with other API operations that produce temporary credentials, see Requesting Temporary Security Credentials and Compare STS credentials in the IAM User Guide.

Permissions

The temporary security credentials created by AssumeRole can be used to make API calls to any Amazon Web Services service with the following exception: You cannot call the Amazon Web Services STS GetFederationToken or GetSessionToken API operations.

(Optional) You can pass inline or managed session policies to this operation. You can pass a single JSON policy document to use as an inline session policy. You can also specify up to 10 managed policy Amazon Resource Names (ARNs) to use as managed session policies. The plaintext that you use for both inline and managed session policies can't exceed 2,048 characters. Passing policies to this operation returns new temporary credentials. The resulting session's permissions are the intersection of the role's identity-based policy and the session policies. You can use the role's temporary credentials in subsequent Amazon Web Services API calls to access resources in the account that owns the role. You cannot use session policies to grant more permissions than those allowed by the identity-based policy of the role that is being assumed. For more information, see Session Policies in the IAM User Guide.

When you create a role, you create two policies: a role trust policy that specifies who can assume the role, and a permissions policy that specifies what can be done with the role. You specify the trusted principal that is allowed to assume the role in the role trust policy.

To assume a role from a different account, your Amazon Web Services account must be trusted by the role. The trust relationship is defined in the role's trust policy when the role is created. That trust policy states which accounts are allowed to delegate that access to users in the account.

A user who wants to access a role in a different account must also have permissions that are delegated from the account administrator. The administrator must attach a policy that allows the user to call AssumeRole for the ARN of the role in the other account.

To allow a user to assume a role in the same account, you can do either of the following:

Attach a policy to the user that allows the user to call AssumeRole (as long as the role's trust policy trusts the account).
Add the user as a principal directly in the role's trust policy.

You can do either because the role’s trust policy acts as an IAM resource-based policy. When a resource-based policy grants access to a principal in the same account, no additional identity-based policy is required. For more information about trust policies and resource-based policies, see IAM Policies in the IAM User Guide.

Tags

(Optional) You can pass tag key-value pairs to your session. These tags are called session tags. For more information about session tags, see Passing Session Tags in STS in the IAM User Guide.

An administrator must grant you the permissions necessary to pass session tags. The administrator can also create granular permissions to allow you to pass only specific session tags. For more information, see Tutorial: Using Tags for Attribute-Based Access Control in the IAM User Guide.

You can set the session tags as transitive. Transitive tags persist during role chaining. For more information, see Chaining Roles with Session Tags in the IAM User Guide.

Using MFA with AssumeRole

(Optional) You can include multi-factor authentication (MFA) information when you call AssumeRole. This is useful for cross-account scenarios to ensure that the user that assumes the role has been authenticated with an Amazon Web Services MFA device. In that scenario, the trust policy of the role being assumed includes a condition that tests for MFA authentication. If the caller does not include valid MFA information, the request to assume the role is denied. The condition in a trust policy that tests for MFA authentication might look like the following example.

"Condition": {"Bool": {"aws:MultiFactorAuthPresent": true}}

For more information, see Configuring MFA-Protected API Access in the IAM User Guide guide.

To use MFA with AssumeRole, you pass values for the SerialNumber and TokenCode parameters. The SerialNumber value identifies the user's hardware or virtual MFA device. The TokenCode is the time-based one-time password (TOTP) that the MFA device produces.

See also: AWS API Documentation

Request Syntax

client.assume_role(
    RoleArn='string',
    RoleSessionName='string',
    PolicyArns=[
        {
            'arn': 'string'
        },
    ],
    Policy='string',
    DurationSeconds=123,
    Tags=[
        {
            'Key': 'string',
            'Value': 'string'
        },
    ],
    TransitiveTagKeys=[
        'string',
    ],
    ExternalId='string',
    SerialNumber='string',
    TokenCode='string',
    SourceIdentity='string',
    ProvidedContexts=[
        {
            'ProviderArn': 'string',
            'ContextAssertion': 'string'
        },
    ],
    MinimumSessionTokenSize=123
)

type RoleArn:

string

param RoleArn:

[REQUIRED]

The Amazon Resource Name (ARN) of the role to assume.

type RoleSessionName:

string

param RoleSessionName:

[REQUIRED]

An identifier for the assumed role session.

Use the role session name to uniquely identify a session when the same role is assumed by different principals or for different reasons. In cross-account scenarios, the role session name is visible to, and can be logged by the account that owns the role. The role session name is also used in the ARN of the assumed role principal. This means that subsequent cross-account API requests that use the temporary security credentials will expose the role session name to the external account in their CloudTrail logs.

For security purposes, administrators can view this field in CloudTrail logs to help identify who performed an action in Amazon Web Services. Your administrator might require that you specify your user name as the session name when you assume the role. For more information, see sts:RoleSessionName.

type PolicyArns:

list

param PolicyArns:

The Amazon Resource Names (ARNs) of the IAM managed policies that you want to use as managed session policies. The policies must exist in the same account as the role.

This parameter is optional. You can provide up to 10 managed policy ARNs. However, the plaintext that you use for both inline and managed session policies can't exceed 2,048 characters. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

Passing policies to this operation returns new temporary credentials. The resulting session's permissions are the intersection of the role's identity-based policy and the session policies. You can use the role's temporary credentials in subsequent Amazon Web Services API calls to access resources in the account that owns the role. You cannot use session policies to grant more permissions than those allowed by the identity-based policy of the role that is being assumed. For more information, see Session Policies in the IAM User Guide.

(dict) --

A reference to the IAM managed policy that is passed as a session policy for a role session or a federated user session.
- arn (string) --
  
  The Amazon Resource Name (ARN) of the IAM managed policy to use as a session policy for the role. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

type Policy:

string

param Policy:

An IAM policy in JSON format that you want to use as an inline session policy.

This parameter is optional. Passing policies to this operation returns new temporary credentials. The resulting session's permissions are the intersection of the role's identity-based policy and the session policies. You can use the role's temporary credentials in subsequent Amazon Web Services API calls to access resources in the account that owns the role. You cannot use session policies to grant more permissions than those allowed by the identity-based policy of the role that is being assumed. For more information, see Session Policies in the IAM User Guide.

The plaintext that you use for both inline and managed session policies can't exceed 2,048 characters. The JSON policy characters can be any ASCII character from the space character to the end of the valid character list (u0020 through u00FF). It can also include the tab (u0009), linefeed (u000A), and carriage return (u000D) characters.

For more information about role session permissions, see Session policies.

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, of the role session. The value specified can range from 900 seconds (15 minutes) up to the maximum session duration set for the role. The maximum session duration setting can have a value from 1 hour to 12 hours. If you specify a value higher than this setting or the administrator setting (whichever is lower), the operation fails. For example, if you specify a session duration of 12 hours, but your administrator set the maximum session duration to 6 hours, your operation fails.

Role chaining limits your Amazon Web Services CLI or Amazon Web Services API role session to a maximum of one hour. When you use the AssumeRole API operation to assume a role, you can specify the duration of your role session with the DurationSeconds parameter. You can specify a parameter value of up to 43200 seconds (12 hours), depending on the maximum session duration setting for your role. However, if you assume a role using role chaining and provide a DurationSeconds parameter value greater than one hour, the operation fails. To learn how to view the maximum value for your role, see Update the maximum session duration for a role.

By default, the value is set to 3600 seconds.

type Tags:

list

param Tags:

A list of session tags that you want to pass. Each session tag consists of a key name and an associated value. For more information about session tags, see Tagging Amazon Web Services STS Sessions in the IAM User Guide.

This parameter is optional. You can pass up to 50 session tags. The plaintext session tag keys can’t exceed 128 characters, and the values can’t exceed 256 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.

You can pass a session tag with the same key as a tag that is already attached to the role. When you do, session tags override a role tag with the same key.

Tag key–value pairs are not case sensitive, but case is preserved. This means that you cannot have separate Department and department tag keys. Assume that the role has the Department``= ``Marketing tag and you pass the department``= ``engineering session tag. Department and department are not saved as separate tags, and the session tag passed in the request takes precedence over the role tag.

Additionally, if you used temporary credentials to perform this operation, the new session inherits any transitive session tags from the calling session. If you pass a session tag with the same key as an inherited tag, the operation fails. To view the inherited tags for a session, see the CloudTrail logs. For more information, see Viewing Session Tags in CloudTrail in the IAM User Guide.

(dict) --

You can pass custom key-value pair attributes when you assume a role or federate a user. These are called session tags. You can then use the session tags to control access to resources. For more information, see Tagging Amazon Web Services STS Sessions in the IAM User Guide.
- Key (string) -- [REQUIRED]
  
  The key for a session tag.
  
  You can pass up to 50 session tags. The plain text session tag keys can’t exceed 128 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.
- Value (string) -- [REQUIRED]
  
  The value for a session tag.
  
  You can pass up to 50 session tags. The plain text session tag values can’t exceed 256 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.

type TransitiveTagKeys:

list

param TransitiveTagKeys:

A list of keys for session tags that you want to set as transitive. If you set a tag key as transitive, the corresponding key and value passes to subsequent sessions in a role chain. For more information, see Chaining Roles with Session Tags in the IAM User Guide.

This parameter is optional. The transitive status of a session tag does not impact its packed binary size.

If you choose not to specify a transitive tag key, then no tags are passed from this session to any subsequent sessions.

(string) --

type ExternalId:

string

param ExternalId:

A unique identifier that might be required when you assume a role in another account. If the administrator of the account to which the role belongs provided you with an external ID, then provide that value in the ExternalId parameter. This value can be any string, such as a passphrase or account number. A cross-account role is usually set up to trust everyone in an account. Therefore, the administrator of the trusting account might send an external ID to the administrator of the trusted account. That way, only someone with the ID can assume the role, rather than everyone in the account. For more information about the external ID, see How to Use an External ID When Granting Access to Your Amazon Web Services Resources to a Third Party in the IAM User Guide.

type SerialNumber:

string

param SerialNumber:

The identification number of the MFA device that is associated with the user who is making the AssumeRole call. Specify this value if the trust policy of the role being assumed includes a condition that requires MFA authentication. The value is either the serial number for a hardware device (such as GAHT12345678) or an Amazon Resource Name (ARN) for a virtual device (such as arn:aws:iam::123456789012:mfa/user).

type TokenCode:

string

param TokenCode:

The value provided by the MFA device, if the trust policy of the role being assumed requires MFA. (In other words, if the policy includes a condition that tests for MFA). If the role being assumed requires MFA and if the TokenCode value is missing or expired, the AssumeRole call returns an "access denied" error.

The format for this parameter, as described by its regex pattern, is a sequence of six numeric digits.

type SourceIdentity:

string

param SourceIdentity:

The source identity specified by the principal that is calling the AssumeRole operation. The source identity value persists across chained role sessions.

You can require users to specify a source identity when they assume a role. You do this by using the sts:SourceIdentity condition key in a role trust policy. You can use source identity information in CloudTrail logs to determine who took actions with a role. You can use the aws:SourceIdentity condition key to further control access to Amazon Web Services resources based on the value of source identity. For more information about using source identity, see Monitor and control actions taken with assumed roles in the IAM User Guide.

The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: +=,.@-. You cannot use a value that begins with the text aws:. This prefix is reserved for Amazon Web Services internal use.

type ProvidedContexts:

list

param ProvidedContexts:

A list of previously acquired trusted context assertions in the format of a JSON array. The trusted context assertion is signed and encrypted by Amazon Web Services STS.

The following is an example of a ProvidedContext value that includes a single trusted context assertion and the ARN of the context provider from which the trusted context assertion was generated.

[{"ProviderArn":"arn:aws:iam::aws:contextProvider/IdentityCenter","ContextAssertion":"trusted-context-assertion"}]

(dict) --

Contains information about the provided context. This includes the signed and encrypted trusted context assertion and the context provider ARN from which the trusted context assertion was generated.
- ProviderArn (string) --
  
  The context provider ARN from which the trusted context assertion was generated.
- ContextAssertion (string) --
  
  The signed and encrypted trusted context assertion generated by the context provider. The trusted context assertion is signed and encrypted by Amazon Web Services STS.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

The minimum size, in bytes, of the session token that STS issues for the request. STS increases the session token to at least this size, regardless of its actual content. The value must not exceed 4,096 bytes. When set to 0 or not specified, the session token size is unchanged.

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'AssumedRoleUser': {
        'AssumedRoleId': 'string',
        'Arn': 'string'
    },
    'PackedPolicySize': 123,
    'SourceIdentity': 'string',
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --

Contains the response to a successful AssumeRole request, including temporary Amazon Web Services credentials that can be used to make Amazon Web Services requests.
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security (or session) token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- AssumedRoleUser (dict) --
  
  The Amazon Resource Name (ARN) and the assumed role ID, which are identifiers that you can use to refer to the resulting temporary security credentials. For example, you can reference these credentials as a principal in a resource-based policy by using the ARN or assumed role ID. The ARN and ID include the RoleSessionName that you specified when you called AssumeRole.
  - AssumedRoleId (string) --
    
    A unique identifier that contains the role ID and the role session name of the role that is being assumed. The role ID is generated by Amazon Web Services when the role is created.
  - Arn (string) --
    
    The ARN of the temporary security credentials that are returned from the AssumeRole action. For more information about ARNs and how to use them in policies, see IAM Identifiers in the IAM User Guide.
- PackedPolicySize (integer) --
  
  A percentage value that indicates the packed size of the session policies and session tags combined passed in the request. The request fails if the packed size is greater than 100 percent, which means the policies and tags exceeded the allowed space.
- SourceIdentity (string) --
  
  The source identity specified by the principal that is calling the AssumeRole operation.
  
  You can require users to specify a source identity when they assume a role. You do this by using the sts:SourceIdentity condition key in a role trust policy. You can use source identity information in CloudTrail logs to determine who took actions with a role. You can use the aws:SourceIdentity condition key to further control access to Amazon Web Services resources based on the value of source identity. For more information about using source identity, see Monitor and control actions taken with assumed roles in the IAM User Guide.
  
  The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@-
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.

AssumeRoleWithSAML (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of temporary security credentials for users who have been authenticated via a SAML authentication response. This operation provides a mechanism for tying an enterprise identity store or directory to role-based Amazon Web Services access without user-specific credentials or configuration. For a comparison of AssumeRoleWithSAML with the other API operations that produce temporary credentials, see Requesting Temporary Security Credentials and Compare STS credentials in the IAM User Guide.

The temporary security credentials returned by this operation consist of an access key ID, a secret access key, and a security token. Applications can use these temporary security credentials to sign calls to Amazon Web Services services.

Session Duration

By default, the temporary security credentials created by AssumeRoleWithSAML last for one hour. However, you can use the optional DurationSeconds parameter to specify the duration of your session. Your role session lasts for the duration that you specify, or until the time specified in the SAML authentication response's SessionNotOnOrAfter value, whichever is shorter. You can provide a DurationSeconds value from 900 seconds (15 minutes) up to the maximum session duration setting for the role. This setting can have a value from 1 hour to 12 hours. To learn how to view the maximum value for your role, see View the Maximum Session Duration Setting for a Role in the IAM User Guide. The maximum session duration limit applies when you use the AssumeRole* API operations or the assume-role* CLI commands. However the limit does not apply when you use those operations to create a console URL. For more information, see Using IAM Roles in the IAM User Guide.

Permissions

The temporary security credentials created by AssumeRoleWithSAML can be used to make API calls to any Amazon Web Services service with the following exception: you cannot call the STS GetFederationToken or GetSessionToken API operations.

Calling AssumeRoleWithSAML does not require the use of Amazon Web Services security credentials. The identity of the caller is validated by using keys in the metadata document that is uploaded for the SAML provider entity for your identity provider.

Tags

(Optional) You can configure your IdP to pass attributes into your SAML assertion as session tags. Each session tag consists of a key name and an associated value. For more information about session tags, see Passing Session Tags in STS in the IAM User Guide.

You can pass up to 50 session tags. The plaintext session tag keys can’t exceed 128 characters and the values can’t exceed 256 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.

You can pass a session tag with the same key as a tag that is attached to the role. When you do, session tags override the role's tags with the same key.

You can set the session tags as transitive. Transitive tags persist during role chaining. For more information, see Chaining Roles with Session Tags in the IAM User Guide.

SAML Configuration

Before your application can call AssumeRoleWithSAML, you must configure your SAML identity provider (IdP) to issue the claims required by Amazon Web Services. Additionally, you must use Identity and Access Management (IAM) to create a SAML provider entity in your Amazon Web Services account that represents your identity provider. You must also create an IAM role that specifies this SAML provider in its trust policy.

For more information, see the following resources:

About SAML 2.0-based Federation in the IAM User Guide.
Creating SAML Identity Providers in the IAM User Guide.
Configuring a Relying Party and Claims in the IAM User Guide.
Creating a Role for SAML 2.0 Federation in the IAM User Guide.

See also: AWS API Documentation

Request Syntax

client.assume_role_with_saml(
    RoleArn='string',
    PrincipalArn='string',
    SAMLAssertion='string',
    PolicyArns=[
        {
            'arn': 'string'
        },
    ],
    Policy='string',
    DurationSeconds=123,
    MinimumSessionTokenSize=123
)

type RoleArn:

string

param RoleArn:

[REQUIRED]

The Amazon Resource Name (ARN) of the role that the caller is assuming.

type PrincipalArn:

string

param PrincipalArn:

[REQUIRED]

The Amazon Resource Name (ARN) of the SAML provider in IAM that describes the IdP.

type SAMLAssertion:

string

param SAMLAssertion:

[REQUIRED]

The base64 encoded SAML authentication response provided by the IdP.

For more information, see Configuring a Relying Party and Adding Claims in the IAM User Guide.

type PolicyArns:

list

param PolicyArns:

The Amazon Resource Names (ARNs) of the IAM managed policies that you want to use as managed session policies. The policies must exist in the same account as the role.

(dict) --

A reference to the IAM managed policy that is passed as a session policy for a role session or a federated user session.
- arn (string) --
  
  The Amazon Resource Name (ARN) of the IAM managed policy to use as a session policy for the role. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

type Policy:

string

param Policy:

An IAM policy in JSON format that you want to use as an inline session policy.

For more information about role session permissions, see Session policies.

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, of the role session. Your role session lasts for the duration that you specify for the DurationSeconds parameter, or until the time specified in the SAML authentication response's SessionNotOnOrAfter value, whichever is shorter. You can provide a DurationSeconds value from 900 seconds (15 minutes) up to the maximum session duration setting for the role. This setting can have a value from 1 hour to 12 hours. If you specify a value higher than this setting, the operation fails. For example, if you specify a session duration of 12 hours, but your administrator set the maximum session duration to 6 hours, your operation fails. To learn how to view the maximum value for your role, see View the Maximum Session Duration Setting for a Role in the IAM User Guide.

By default, the value is set to 3600 seconds.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'AssumedRoleUser': {
        'AssumedRoleId': 'string',
        'Arn': 'string'
    },
    'PackedPolicySize': 123,
    'Subject': 'string',
    'SubjectType': 'string',
    'Issuer': 'string',
    'Audience': 'string',
    'NameQualifier': 'string',
    'SourceIdentity': 'string',
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --

Contains the response to a successful AssumeRoleWithSAML request, including temporary Amazon Web Services credentials that can be used to make Amazon Web Services requests.
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security (or session) token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- AssumedRoleUser (dict) --
  
  The identifiers for the temporary security credentials that the operation returns.
  - AssumedRoleId (string) --
    
    A unique identifier that contains the role ID and the role session name of the role that is being assumed. The role ID is generated by Amazon Web Services when the role is created.
  - Arn (string) --
    
    The ARN of the temporary security credentials that are returned from the AssumeRole action. For more information about ARNs and how to use them in policies, see IAM Identifiers in the IAM User Guide.
- PackedPolicySize (integer) --
  
  A percentage value that indicates the packed size of the session policies and session tags combined passed in the request. The request fails if the packed size is greater than 100 percent, which means the policies and tags exceeded the allowed space.
- Subject (string) --
  
  The value of the NameID element in the Subject element of the SAML assertion.
- SubjectType (string) --
  
  The format of the name ID, as defined by the Format attribute in the NameID element of the SAML assertion. Typical examples of the format are transient or persistent.
  
  If the format includes the prefix urn:oasis:names:tc:SAML:2.0:nameid-format, that prefix is removed. For example, urn:oasis:names:tc:SAML:2.0:nameid-format:transient is returned as transient. If the format includes any other prefix, the format is returned with no modifications.
- Issuer (string) --
  
  The value of the Issuer element of the SAML assertion.
- Audience (string) --
  
  The value of the Recipient attribute of the SubjectConfirmationData element of the SAML assertion.
- NameQualifier (string) --
  
  A hash value based on the concatenation of the following:
  - The Issuer response value.
  - The Amazon Web Services account ID.
  - The friendly name (the last part of the ARN) of the SAML provider in IAM.
  The combination of NameQualifier and Subject can be used to uniquely identify a user.
  
  The following pseudocode shows how the hash value is calculated:
  
  BASE64 ( SHA1 ( "https://example.com/saml" + "123456789012" + "/MySAMLIdP" ) )
- SourceIdentity (string) --
  
  The value in the SourceIdentity attribute in the SAML assertion. The source identity value persists across chained role sessions.
  
  You can require users to set a source identity value when they assume a role. You do this by using the sts:SourceIdentity condition key in a role trust policy. That way, actions that are taken with the role are associated with that user. After the source identity is set, the value cannot be changed. It is present in the request for all actions that are taken by the role and persists across chained role sessions. You can configure your SAML identity provider to use an attribute associated with your users, like user name or email, as the source identity when calling AssumeRoleWithSAML. You do this by adding an attribute to the SAML assertion. For more information about using source identity, see Monitor and control actions taken with assumed roles in the IAM User Guide.
  
  The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@-
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.

AssumeRoleWithWebIdentity (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of temporary security credentials for users who have been authenticated in a mobile or web application with a web identity provider. Example providers include the OAuth 2.0 providers Login with Amazon and Facebook, or any OpenID Connect-compatible identity provider such as Google or Amazon Cognito federated identities.

Calling AssumeRoleWithWebIdentity does not require the use of Amazon Web Services security credentials. Therefore, you can distribute an application (for example, on mobile devices) that requests temporary security credentials without including long-term Amazon Web Services credentials in the application. You also don't need to deploy server-based proxy services that use long-term Amazon Web Services credentials. Instead, the identity of the caller is validated by using a token from the web identity provider. For a comparison of AssumeRoleWithWebIdentity with the other API operations that produce temporary credentials, see Requesting Temporary Security Credentials and Compare STS credentials in the IAM User Guide.

The temporary security credentials returned by this API consist of an access key ID, a secret access key, and a security token. Applications can use these temporary security credentials to sign calls to Amazon Web Services service API operations.

Session Duration

By default, the temporary security credentials created by AssumeRoleWithWebIdentity last for one hour. However, you can use the optional DurationSeconds parameter to specify the duration of your session. You can provide a value from 900 seconds (15 minutes) up to the maximum session duration setting for the role. This setting can have a value from 1 hour to 12 hours. To learn how to view the maximum value for your role, see Update the maximum session duration for a role in the IAM User Guide. The maximum session duration limit applies when you use the AssumeRole* API operations or the assume-role* CLI commands. However the limit does not apply when you use those operations to create a console URL. For more information, see Using IAM Roles in the IAM User Guide.

Permissions

The temporary security credentials created by AssumeRoleWithWebIdentity can be used to make API calls to any Amazon Web Services service with the following exception: you cannot call the STS GetFederationToken or GetSessionToken API operations.

Tags

(Optional) You can configure your IdP to pass attributes into your web identity token as session tags. Each session tag consists of a key name and an associated value. For more information about session tags, see Passing session tags using AssumeRoleWithWebIdentity in the IAM User Guide.

You can pass a session tag with the same key as a tag that is attached to the role. When you do, the session tag overrides the role tag with the same key.

You can set the session tags as transitive. Transitive tags persist during role chaining. For more information, see Chaining Roles with Session Tags in the IAM User Guide.

Identities

Before your application can call AssumeRoleWithWebIdentity, you must have an identity token from a supported identity provider and create a role that the application can assume. The role that your application assumes must trust the identity provider that is associated with the identity token. In other words, the identity provider must be specified in the role's trust policy.

For more information about how to use OIDC federation and the AssumeRoleWithWebIdentity API, see the following resources:

Using Web Identity Federation API Operations for Mobile Apps and Federation Through a Web-based Identity Provider.
Amazon Web Services SDK for iOS Developer Guide and Amazon Web Services SDK for Android Developer Guide. These toolkits contain sample apps that show how to invoke the identity providers. The toolkits then show how to use the information from these providers to get and use temporary security credentials.

See also: AWS API Documentation

Request Syntax

client.assume_role_with_web_identity(
    RoleArn='string',
    RoleSessionName='string',
    WebIdentityToken='string',
    ProviderId='string',
    PolicyArns=[
        {
            'arn': 'string'
        },
    ],
    Policy='string',
    DurationSeconds=123,
    MinimumSessionTokenSize=123
)

type RoleArn:

string

param RoleArn:

[REQUIRED]

The Amazon Resource Name (ARN) of the role that the caller is assuming.

type RoleSessionName:

string

param RoleSessionName:

[REQUIRED]

An identifier for the assumed role session. Typically, you pass the name or identifier that is associated with the user who is using your application. That way, the temporary security credentials that your application will use are associated with that user. This session name is included as part of the ARN and assumed role ID in the AssumedRoleUser response element.

type WebIdentityToken:

string

param WebIdentityToken:

[REQUIRED]

The OAuth 2.0 access token or OpenID Connect ID token that is provided by the identity provider. Your application must get this token by authenticating the user who is using your application with a web identity provider before the application makes an AssumeRoleWithWebIdentity call. Timestamps in the token must be formatted as either an integer or a long integer. Tokens must be signed using either RSA keys (RS256, RS384, or RS512) or ECDSA keys (ES256, ES384, or ES512).

type ProviderId:

string

param ProviderId:

The fully qualified host component of the domain name of the OAuth 2.0 identity provider. Do not specify this value for an OpenID Connect identity provider.

Currently www.amazon.com and graph.facebook.com are the only supported identity providers for OAuth 2.0 access tokens. Do not include URL schemes and port numbers.

Do not specify this value for OpenID Connect ID tokens.

type PolicyArns:

list

param PolicyArns:

The Amazon Resource Names (ARNs) of the IAM managed policies that you want to use as managed session policies. The policies must exist in the same account as the role.

(dict) --

A reference to the IAM managed policy that is passed as a session policy for a role session or a federated user session.
- arn (string) --
  
  The Amazon Resource Name (ARN) of the IAM managed policy to use as a session policy for the role. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

type Policy:

string

param Policy:

An IAM policy in JSON format that you want to use as an inline session policy.

For more information about role session permissions, see Session policies.

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, of the role session. The value can range from 900 seconds (15 minutes) up to the maximum session duration setting for the role. This setting can have a value from 1 hour to 12 hours. If you specify a value higher than this setting, the operation fails. For example, if you specify a session duration of 12 hours, but your administrator set the maximum session duration to 6 hours, your operation fails. To learn how to view the maximum value for your role, see View the Maximum Session Duration Setting for a Role in the IAM User Guide.

By default, the value is set to 3600 seconds.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'SubjectFromWebIdentityToken': 'string',
    'AssumedRoleUser': {
        'AssumedRoleId': 'string',
        'Arn': 'string'
    },
    'PackedPolicySize': 123,
    'Provider': 'string',
    'Audience': 'string',
    'SourceIdentity': 'string',
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --

Contains the response to a successful AssumeRoleWithWebIdentity request, including temporary Amazon Web Services credentials that can be used to make Amazon Web Services requests.
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- SubjectFromWebIdentityToken (string) --
  
  The unique user identifier that is returned by the identity provider. This identifier is associated with the WebIdentityToken that was submitted with the AssumeRoleWithWebIdentity call. The identifier is typically unique to the user and the application that acquired the WebIdentityToken (pairwise identifier). For OpenID Connect ID tokens, this field contains the value returned by the identity provider as the token's sub (Subject) claim.
- AssumedRoleUser (dict) --
  
  The Amazon Resource Name (ARN) and the assumed role ID, which are identifiers that you can use to refer to the resulting temporary security credentials. For example, you can reference these credentials as a principal in a resource-based policy by using the ARN or assumed role ID. The ARN and ID include the RoleSessionName that you specified when you called AssumeRole.
  - AssumedRoleId (string) --
    
    A unique identifier that contains the role ID and the role session name of the role that is being assumed. The role ID is generated by Amazon Web Services when the role is created.
  - Arn (string) --
    
    The ARN of the temporary security credentials that are returned from the AssumeRole action. For more information about ARNs and how to use them in policies, see IAM Identifiers in the IAM User Guide.
- PackedPolicySize (integer) --
  
  A percentage value that indicates the packed size of the session policies and session tags combined passed in the request. The request fails if the packed size is greater than 100 percent, which means the policies and tags exceeded the allowed space.
- Provider (string) --
  
  The issuing authority of the web identity token presented. For OpenID Connect ID tokens, this contains the value of the iss field. For OAuth 2.0 access tokens, this contains the value of the ProviderId parameter that was passed in the AssumeRoleWithWebIdentity request.
- Audience (string) --
  
  The intended audience (also known as client ID) of the web identity token. This is traditionally the client identifier issued to the application that requested the web identity token.
- SourceIdentity (string) --
  
  The value of the source identity that is returned in the JSON web token (JWT) from the identity provider.
  
  You can require users to set a source identity value when they assume a role. You do this by using the sts:SourceIdentity condition key in a role trust policy. That way, actions that are taken with the role are associated with that user. After the source identity is set, the value cannot be changed. It is present in the request for all actions that are taken by the role and persists across chained role sessions. You can configure your identity provider to use an attribute associated with your users, like user name or email, as the source identity when calling AssumeRoleWithWebIdentity. You do this by adding a claim to the JSON web token. To learn more about OIDC tokens and claims, see Using Tokens with User Pools in the Amazon Cognito Developer Guide. For more information about using source identity, see Monitor and control actions taken with assumed roles in the IAM User Guide.
  
  The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@-
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.

AssumeRoot (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of short term credentials you can use to perform privileged tasks on a member account in your organization. You must use credentials from an Organizations management account or a delegated administrator account for IAM to call AssumeRoot. You cannot use root user credentials to make this call.

Before you can launch a privileged session, you must have centralized root access in your organization. For steps to enable this feature, see Centralize root access for member accounts in the IAM User Guide.

You can track AssumeRoot in CloudTrail logs to determine what actions were performed in a session. For more information, see Track privileged tasks in CloudTrail in the IAM User Guide.

When granting access to privileged tasks you should only grant the necessary permissions required to perform that task. For more information, see Security best practices in IAM. In addition, you can use service control policies (SCPs) to manage and limit permissions in your organization. See General examples in the Organizations User Guide for more information on SCPs.

See also: AWS API Documentation

Request Syntax

client.assume_root(
    TargetPrincipal='string',
    TaskPolicyArn={
        'arn': 'string'
    },
    DurationSeconds=123,
    MinimumSessionTokenSize=123
)

type TargetPrincipal:

string

param TargetPrincipal:

[REQUIRED]

The member account principal ARN or account ID.

type TaskPolicyArn:

dict

param TaskPolicyArn:

[REQUIRED]

The identity based policy that scopes the session to the privileged tasks that can be performed. You must use one of following Amazon Web Services managed policies to scope root session actions:

arn (string) --

The Amazon Resource Name (ARN) of the IAM managed policy to use as a session policy for the role. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, of the privileged session. The value can range from 0 seconds up to the maximum session duration of 900 seconds (15 minutes). If you specify a value higher than this setting, the operation fails.

By default, the value is set to 900 seconds.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'SourceIdentity': 'string',
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- SourceIdentity (string) --
  
  The source identity specified by the principal that is calling the AssumeRoot operation.
  
  You can use the aws:SourceIdentity condition key to control access based on the value of source identity. For more information about using source identity, see Monitor and control actions taken with assumed roles in the IAM User Guide.
  
  The regex used to validate this parameter is a string of characters consisting of upper- and lower-case alphanumeric characters with no spaces. You can also include underscores or any of the following characters: =,.@-
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.

GetFederationToken (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of temporary security credentials (consisting of an access key ID, a secret access key, and a security token) for a user. A typical use is in a proxy application that gets temporary security credentials on behalf of distributed applications inside a corporate network.

You must call the GetFederationToken operation using the long-term security credentials of an IAM user. As a result, this call is appropriate in contexts where those credentials can be safeguarded, usually in a server-based application. For a comparison of GetFederationToken with the other API operations that produce temporary credentials, see Requesting Temporary Security Credentials and Compare STS credentials in the IAM User Guide.

Although it is possible to call GetFederationToken using the security credentials of an Amazon Web Services account root user rather than an IAM user that you create for the purpose of a proxy application, we do not recommend it. For more information, see Safeguard your root user credentials and don't use them for everyday tasks in the IAM User Guide.

Session duration

The temporary credentials are valid for the specified duration, from 900 seconds (15 minutes) up to a maximum of 129,600 seconds (36 hours). The default session duration is 43,200 seconds (12 hours). Temporary credentials obtained by using the root user credentials have a maximum duration of 3,600 seconds (1 hour).

Permissions

You can use the temporary credentials created by GetFederationToken in any Amazon Web Services service with the following exceptions:

You cannot call any IAM operations using the CLI or the Amazon Web Services API. This limitation does not apply to console sessions.
You cannot call any STS operations except GetCallerIdentity.

You can use temporary credentials for single sign-on (SSO) to the console.

Though the session policy parameters are optional, if you do not pass a policy, then the resulting federated user session has no permissions. When you pass session policies, the session permissions are the intersection of the IAM user policies and the session policies that you pass. This gives you a way to further restrict the permissions for a federated user. You cannot use session policies to grant more permissions than those that are defined in the permissions policy of the IAM user. For more information, see Session Policies in the IAM User Guide. For information about using GetFederationToken to create temporary security credentials, see GetFederationToken—Federation Through a Custom Identity Broker.

You can use the credentials to access a resource that has a resource-based policy. If that policy specifically references the federated user session in the Principal element of the policy, the session has the permissions allowed by the policy. These permissions are granted in addition to the permissions granted by the session policies.

Tags

(Optional) You can pass tag key-value pairs to your session. These are called session tags. For more information about session tags, see Passing Session Tags in STS in the IAM User Guide.

Tag key–value pairs are not case sensitive, but case is preserved. This means that you cannot have separate Department and department tag keys. Assume that the user that you are federating has the Department``= ``Marketing tag and you pass the department``= ``engineering session tag. Department and department are not saved as separate tags, and the session tag passed in the request takes precedence over the user tag.

See also: AWS API Documentation

Request Syntax

client.get_federation_token(
    Name='string',
    Policy='string',
    PolicyArns=[
        {
            'arn': 'string'
        },
    ],
    DurationSeconds=123,
    Tags=[
        {
            'Key': 'string',
            'Value': 'string'
        },
    ],
    MinimumSessionTokenSize=123
)

type Name:

string

param Name:

[REQUIRED]

The name of the federated user. The name is used as an identifier for the temporary security credentials (such as Bob). For example, you can reference the federated user name in a resource-based policy, such as in an Amazon S3 bucket policy.

type Policy:

string

param Policy:

An IAM policy in JSON format that you want to use as an inline session policy.

This parameter is optional. However, if you do not pass any session policies, then the resulting federated user session has no permissions.

When you pass session policies, the session permissions are the intersection of the IAM user policies and the session policies that you pass. This gives you a way to further restrict the permissions for a federated user. You cannot use session policies to grant more permissions than those that are defined in the permissions policy of the IAM user. For more information, see Session Policies in the IAM User Guide.

The resulting credentials can be used to access a resource that has a resource-based policy. If that policy specifically references the federated user session in the Principal element of the policy, the session has the permissions allowed by the policy. These permissions are granted in addition to the permissions that are granted by the session policies.

type PolicyArns:

list

param PolicyArns:

The Amazon Resource Names (ARNs) of the IAM managed policies that you want to use as a managed session policy. The policies must exist in the same account as the IAM user that is requesting federated access.

You must pass an inline or managed session policy to this operation. You can pass a single JSON policy document to use as an inline session policy. You can also specify up to 10 managed policy Amazon Resource Names (ARNs) to use as managed session policies. The plaintext that you use for both inline and managed session policies can't exceed 2,048 characters. You can provide up to 10 managed policy ARNs. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

This parameter is optional. However, if you do not pass any session policies, then the resulting federated user session has no permissions.

(dict) --

A reference to the IAM managed policy that is passed as a session policy for a role session or a federated user session.
- arn (string) --
  
  The Amazon Resource Name (ARN) of the IAM managed policy to use as a session policy for the role. For more information about ARNs, see Amazon Resource Names (ARNs) and Amazon Web Services Service Namespaces in the Amazon Web Services General Reference.

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, that the session should last. Acceptable durations for federation sessions range from 900 seconds (15 minutes) to 129,600 seconds (36 hours), with 43,200 seconds (12 hours) as the default. Sessions obtained using root user credentials are restricted to a maximum of 3,600 seconds (one hour). If the specified duration is longer than one hour, the session obtained by using root user credentials defaults to one hour.

type Tags:

list

param Tags:

A list of session tags. Each session tag consists of a key name and an associated value. For more information about session tags, see Passing Session Tags in STS in the IAM User Guide.

This parameter is optional. You can pass up to 50 session tags. The plaintext session tag keys can’t exceed 128 characters and the values can’t exceed 256 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.

You can pass a session tag with the same key as a tag that is already attached to the user you are federating. When you do, session tags override a user tag with the same key.

(dict) --

You can pass custom key-value pair attributes when you assume a role or federate a user. These are called session tags. You can then use the session tags to control access to resources. For more information, see Tagging Amazon Web Services STS Sessions in the IAM User Guide.
- Key (string) -- [REQUIRED]
  
  The key for a session tag.
  
  You can pass up to 50 session tags. The plain text session tag keys can’t exceed 128 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.
- Value (string) -- [REQUIRED]
  
  The value for a session tag.
  
  You can pass up to 50 session tags. The plain text session tag values can’t exceed 256 characters. For these and additional limits, see IAM and STS Character Limits in the IAM User Guide.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'FederatedUser': {
        'FederatedUserId': 'string',
        'Arn': 'string'
    },
    'PackedPolicySize': 123,
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --

Contains the response to a successful GetFederationToken request, including temporary Amazon Web Services credentials that can be used to make Amazon Web Services requests.
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security (or session) token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- FederatedUser (dict) --
  
  Identifiers for the federated user associated with the credentials (such as arn:aws:sts::123456789012:federated-user/Bob or 123456789012:Bob). You can use the federated user's ARN in your resource-based policies, such as an Amazon S3 bucket policy.
  - FederatedUserId (string) --
    
    The string that identifies the federated user associated with the credentials, similar to the unique ID of an IAM user.
  - Arn (string) --
    
    The ARN that specifies the federated user that is associated with the credentials. For more information about ARNs and how to use them in policies, see IAM Identifiers in the IAM User Guide.
- PackedPolicySize (integer) --
  
  A percentage value that indicates the packed size of the session policies and session tags combined passed in the request. The request fails if the packed size is greater than 100 percent, which means the policies and tags exceeded the allowed space.
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.

GetSessionToken (updated)

Link ¶
Changes (request, response)
Request

{'MinimumSessionTokenSize': 'integer'}

Response

{'SessionTokenSize': 'integer', 'SessionTokenUtilization': 'integer'}

Returns a set of temporary credentials for an Amazon Web Services account or IAM user. The credentials consist of an access key ID, a secret access key, and a security token. Typically, you use GetSessionToken if you want to use MFA to protect programmatic calls to specific Amazon Web Services API operations like Amazon EC2 StopInstances.

MFA-enabled IAM users must call GetSessionToken and submit an MFA code that is associated with their MFA device. Using the temporary security credentials that the call returns, IAM users can then make programmatic calls to API operations that require MFA authentication. An incorrect MFA code causes the API to return an access denied error. For a comparison of GetSessionToken with the other API operations that produce temporary credentials, see Requesting Temporary Security Credentials and Compare STS credentials in the IAM User Guide.

Session Duration

The GetSessionToken operation must be called by using the long-term Amazon Web Services security credentials of an IAM user. Credentials that are created by IAM users are valid for the duration that you specify. This duration can range from 900 seconds (15 minutes) up to a maximum of 129,600 seconds (36 hours), with a default of 43,200 seconds (12 hours). Credentials based on account credentials can range from 900 seconds (15 minutes) up to 3,600 seconds (1 hour), with a default of 1 hour.

Permissions

The temporary security credentials created by GetSessionToken can be used to make API calls to any Amazon Web Services service with the following exceptions:

You cannot call any IAM API operations unless MFA authentication information is included in the request.
You cannot call any STS API except AssumeRole or GetCallerIdentity.

The credentials that GetSessionToken returns are based on permissions associated with the IAM user whose credentials were used to call the operation. The temporary credentials have the same permissions as the IAM user.

For more information about using GetSessionToken to create temporary credentials, see Temporary Credentials for Users in Untrusted Environments in the IAM User Guide.

See also: AWS API Documentation

Request Syntax

client.get_session_token(
    DurationSeconds=123,
    SerialNumber='string',
    TokenCode='string',
    MinimumSessionTokenSize=123
)

type DurationSeconds:

integer

param DurationSeconds:

The duration, in seconds, that the credentials should remain valid. Acceptable durations for IAM user sessions range from 900 seconds (15 minutes) to 129,600 seconds (36 hours), with 43,200 seconds (12 hours) as the default. Sessions for Amazon Web Services account owners are restricted to a maximum of 3,600 seconds (one hour). If the duration is longer than one hour, the session for Amazon Web Services account owners defaults to one hour.

type SerialNumber:

string

param SerialNumber:

The identification number of the MFA device that is associated with the IAM user who is making the GetSessionToken call. Specify this value if the IAM user has a policy that requires MFA authentication. The value is either the serial number for a hardware device (such as GAHT12345678) or an Amazon Resource Name (ARN) for a virtual device (such as arn:aws:iam::123456789012:mfa/user). You can find the device for an IAM user by going to the Amazon Web Services Management Console and viewing the user's security credentials.

type TokenCode:

string

param TokenCode:

The value provided by the MFA device, if MFA is required. If any policy requires the IAM user to submit an MFA code, specify this value. If MFA authentication is required, the user must provide a code when requesting a set of temporary security credentials. A user who fails to provide the code receives an "access denied" response when requesting resources that require MFA authentication.

The format for this parameter, as described by its regex pattern, is a sequence of six numeric digits.

type MinimumSessionTokenSize:

integer

param MinimumSessionTokenSize:

rtype:

dict

returns:

Response Syntax

{
    'Credentials': {
        'AccessKeyId': 'string',
        'SecretAccessKey': 'string',
        'SessionToken': 'string',
        'Expiration': datetime(2015, 1, 1)
    },
    'SessionTokenUtilization': 123,
    'SessionTokenSize': 123
}

Response Structure

(dict) --

Contains the response to a successful GetSessionToken request, including temporary Amazon Web Services credentials that can be used to make Amazon Web Services requests.
- Credentials (dict) --
  
  The temporary security credentials, which include an access key ID, a secret access key, and a security (or session) token.
  
  Note
  
  The size of the security token that STS API operations return is not fixed. We strongly recommend that you make no assumptions about the maximum size.
  - AccessKeyId (string) --
    
    The access key ID that identifies the temporary security credentials.
  - SecretAccessKey (string) --
    
    The secret access key that can be used to sign requests.
  - SessionToken (string) --
    
    The token that users must pass to the service API to use the temporary credentials.
  - Expiration (datetime) --
    
    The date on which the current credentials expire.
- SessionTokenUtilization (integer) -- The percentage (0-100) of the maximum allowed session token size that the returned session token consumes.
- SessionTokenSize (integer) -- The size, in bytes, of the session token returned in the Credentials for this response.