# Copyright (c) 2011 Mitch Garnaat http://garnaat.org/ # Copyright (c) 2011, Eucalyptus Systems, Inc. # Copyright (c) 2013 Amazon.com, Inc. or its affiliates. All Rights Reserved # # Permission is hereby granted, free of charge, to any person obtaining a # copy of this software and associated documentation files (the # "Software"), to deal in the Software without restriction, including # without limitation the rights to use, copy, modify, merge, publish, dis- # tribute, sublicense, and/or sell copies of the Software, and to permit # persons to whom the Software is furnished to do so, subject to the fol- # lowing conditions: # # The above copyright notice and this permission notice shall be included # in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS # OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL- # ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT # SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS # IN THE SOFTWARE. from boto.connection import AWSQueryConnection from boto.regioninfo import RegionInfo from boto.sts.credentials import Credentials, FederationToken, AssumedRole from boto.sts.credentials import DecodeAuthorizationMessage import boto import boto.utils import datetime import threading _session_token_cache = {} class STSConnection(AWSQueryConnection): """ AWS Security Token Service The AWS Security Token Service is a web service that enables you to request temporary, limited-privilege credentials for AWS Identity and Access Management (IAM) users or for users that you authenticate (federated users). This guide provides descriptions of the AWS Security Token Service API. For more detailed information about using this service, go to `Using Temporary Security Credentials`_. For information about setting up signatures and authorization through the API, go to `Signing AWS API Requests`_ in the AWS General Reference . For general information about the Query API, go to `Making Query Requests`_ in Using IAM . For information about using security tokens with other AWS products, go to `Using Temporary Security Credentials to Access AWS`_ in Using Temporary Security Credentials . If you're new to AWS and need additional technical information about a specific AWS product, you can find the product's technical documentation at `http://aws.amazon.com/documentation/`_. We will refer to Amazon Identity and Access Management using the abbreviated form IAM. All copyrights and legal protections still apply. """ DefaultRegionName = 'us-east-1' DefaultRegionEndpoint = 'sts.amazonaws.com' APIVersion = '2011-06-15' def __init__(self, aws_access_key_id=None, aws_secret_access_key=None, is_secure=True, port=None, proxy=None, proxy_port=None, proxy_user=None, proxy_pass=None, debug=0, https_connection_factory=None, region=None, path='/', converter=None, validate_certs=True, anon=False, security_token=None, profile_name=None): if not region: region = RegionInfo(self, self.DefaultRegionName, self.DefaultRegionEndpoint, connection_cls=STSConnection) self.region = region self.anon = anon self._mutex = threading.Semaphore() super(STSConnection, self).__init__(aws_access_key_id, aws_secret_access_key, is_secure, port, proxy, proxy_port, proxy_user, proxy_pass, self.region.endpoint, debug, https_connection_factory, path, validate_certs=validate_certs, security_token=security_token, profile_name=profile_name) def _required_auth_capability(self): if self.anon: return ['pure-query'] else: return ['hmac-v4'] def _check_token_cache(self, token_key, duration=None, window_seconds=60): token = _session_token_cache.get(token_key, None) if token: now = datetime.datetime.utcnow() expires = boto.utils.parse_ts(token.expiration) delta = expires - now if delta < datetime.timedelta(seconds=window_seconds): msg = 'Cached session token %s is expired' % token_key boto.log.debug(msg) token = None return token def _get_session_token(self, duration=None, mfa_serial_number=None, mfa_token=None): params = {} if duration: params['DurationSeconds'] = duration if mfa_serial_number: params['SerialNumber'] = mfa_serial_number if mfa_token: params['TokenCode'] = mfa_token return self.get_object('GetSessionToken', params, Credentials, verb='POST') def get_session_token(self, duration=None, force_new=False, mfa_serial_number=None, mfa_token=None): """ Return a valid session token. Because retrieving new tokens from the Secure Token Service is a fairly heavyweight operation this module caches previously retrieved tokens and returns them when appropriate. Each token is cached with a key consisting of the region name of the STS endpoint concatenated with the requesting user's access id. If there is a token in the cache meeting with this key, the session expiration is checked to make sure it is still valid and if so, the cached token is returned. Otherwise, a new session token is requested from STS and it is placed into the cache and returned. :type duration: int :param duration: The number of seconds the credentials should remain valid. :type force_new: bool :param force_new: If this parameter is True, a new session token will be retrieved from the Secure Token Service regardless of whether there is a valid cached token or not. :type mfa_serial_number: str :param mfa_serial_number: The serial number of an MFA device. If this is provided and if the mfa_passcode provided is valid, the temporary session token will be authorized with to perform operations requiring the MFA device authentication. :type mfa_token: str :param mfa_token: The 6 digit token associated with the MFA device. """ token_key = '%s:%s' % (self.region.name, self.provider.access_key) token = self._check_token_cache(token_key, duration) if force_new or not token: boto.log.debug('fetching a new token for %s' % token_key) try: self._mutex.acquire() token = self._get_session_token(duration, mfa_serial_number, mfa_token) _session_token_cache[token_key] = token finally: self._mutex.release() return token def get_federation_token(self, name, duration=None, policy=None): """ Returns a set of temporary security credentials (consisting of an access key ID, a secret access key, and a security token) for a federated user. A typical use is in a proxy application that is getting temporary security credentials on behalf of distributed applications inside a corporate network. Because you must call the `GetFederationToken` action using the long- term security credentials of an IAM user, this call is appropriate in contexts where those credentials can be safely stored, usually in a server-based application. **Note:** Do not use this call in mobile applications or client-based web applications that directly get temporary security credentials. For those types of applications, use `AssumeRoleWithWebIdentity`. The `GetFederationToken` action must be called by using the long-term AWS security credentials of the AWS account or an IAM user. Credentials that are created by IAM users are valid for the specified duration, between 900 seconds (15 minutes) and 129600 seconds (36 hours); credentials that are created by using account credentials have a maximum duration of 3600 seconds (1 hour). The permissions that are granted to the federated user are the intersection of the policy that is passed with the `GetFederationToken` request and policies that are associated with of the entity making the `GetFederationToken` call. For more information about how permissions work, see `Controlling Permissions in Temporary Credentials`_ in Using Temporary Security Credentials . For information about using `GetFederationToken` to create temporary security credentials, see `Creating Temporary Credentials to Enable Access for Federated Users`_ in Using Temporary Security Credentials . :type name: string :param name: 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: A policy that specifies the permissions that are granted to the federated user. By default, federated users have no permissions; they do not inherit any from the IAM user. When you specify a policy, the federated user's permissions are intersection of the specified policy and the IAM user's policy. If you don't specify a policy, federated users can only access AWS resources that explicitly allow those federated users in a resource policy, such as in an Amazon S3 bucket policy. :type duration: integer :param duration: The duration, in seconds, that the session should last. Acceptable durations for federation sessions range from 900 seconds (15 minutes) to 129600 seconds (36 hours), with 43200 seconds (12 hours) as the default. Sessions for AWS account owners are restricted to a maximum of 3600 seconds (one hour). If the duration is longer than one hour, the session for AWS account owners defaults to one hour. """ params = {'Name': name} if duration: params['DurationSeconds'] = duration if policy: params['Policy'] = policy return self.get_object('GetFederationToken', params, FederationToken, verb='POST') def assume_role(self, role_arn, role_session_name, policy=None, duration_seconds=None, external_id=None, mfa_serial_number=None, mfa_token=None): """ Returns a set of temporary security credentials (consisting of an access key ID, a secret access key, and a security token) that you can use to access AWS resources that you might not normally have access to. Typically, you use `AssumeRole` for cross-account access or federation. For cross-account access, imagine that you own multiple accounts and need to access resources in each account. You could create long-term credentials in each account to access those resources. However, managing all those credentials and remembering which one can access which account can be time consuming. Instead, you can create one set of long-term credentials in one account and then use temporary security credentials to access all the other accounts by assuming roles in those accounts. For more information about roles, see `Roles`_ in Using IAM . For federation, you can, for example, grant single sign-on access to the AWS Management Console. If you already have an identity and authentication system in your corporate network, you don't have to recreate user identities in AWS in order to grant those user identities access to AWS. Instead, after a user has been authenticated, you call `AssumeRole` (and specify the role with the appropriate permissions) to get temporary security credentials for that user. With those temporary security credentials, you construct a sign-in URL that users can use to access the console. For more information, see `Scenarios for Granting Temporary Access`_ in AWS Security Token Service . The temporary security credentials are valid for the duration that you specified when calling `AssumeRole`, which can be from 900 seconds (15 minutes) to 3600 seconds (1 hour). The default is 1 hour. The temporary security credentials that are returned from the `AssumeRoleWithWebIdentity` response have the permissions that are associated with the access policy of the role being assumed and any policies that are associated with the AWS resource being accessed. You can further restrict the permissions of the temporary security credentials by passing a policy in the request. The resulting permissions are an intersection of the role's access policy and the policy that you passed. These policies and any applicable resource-based policies are evaluated when calls to AWS service APIs are made using the temporary security credentials. To assume a role, your AWS account must be trusted by the role. The trust relationship is defined in the role's trust policy when the IAM role is created. You must also have a policy that allows you to call `sts:AssumeRole`. **Important:** You cannot call `Assumerole` by using AWS account credentials; access will be denied. You must use IAM user credentials to call `AssumeRole`. :type role_arn: string :param role_arn: The Amazon Resource Name (ARN) of the role that the caller is assuming. :type role_session_name: string :param role_session_name: An identifier for the assumed role session. The session name is included as part of the `AssumedRoleUser`. :type policy: string :param policy: A supplemental policy that is associated with the temporary security credentials from the `AssumeRole` call. The resulting permissions of the temporary security credentials are an intersection of this policy and the access policy that is associated with the role. Use this policy to further restrict the permissions of the temporary security credentials. :type duration_seconds: integer :param duration_seconds: The duration, in seconds, of the role session. The value can range from 900 seconds (15 minutes) to 3600 seconds (1 hour). By default, the value is set to 3600 seconds. :type external_id: string :param external_id: A unique identifier that is used by third parties to assume a role in their customers' accounts. For each role that the third party can assume, they should instruct their customers to create a role with the external ID that the third party generated. Each time the third party assumes the role, they must pass the customer's external ID. The external ID is useful in order to help third parties bind a role to the customer who created it. For more information about the external ID, see `About the External ID`_ in Using Temporary Security Credentials . :type mfa_serial_number: string :param mfa_serial_number: 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). Minimum length of 9. Maximum length of 256. :type mfa_token: string :param mfa_token: The value provided by the MFA device, if the trust policy of the role being assumed requires MFA (that is, 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" errror. Minimum length of 6. Maximum length of 6. """ params = { 'RoleArn': role_arn, 'RoleSessionName': role_session_name } if policy is not None: params['Policy'] = policy if duration_seconds is not None: params['DurationSeconds'] = duration_seconds if external_id is not None: params['ExternalId'] = external_id if mfa_serial_number is not None: params['SerialNumber'] = mfa_serial_number if mfa_token is not None: params['TokenCode'] = mfa_token return self.get_object('AssumeRole', params, AssumedRole, verb='POST') def assume_role_with_saml(self, role_arn, principal_arn, saml_assertion, policy=None, duration_seconds=None): """ 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 AWS access without user-specific credentials or configuration. 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 AWS services. The credentials are valid for the duration that you specified when calling `AssumeRoleWithSAML`, which can be up to 3600 seconds (1 hour) or until the time specified in the SAML authentication response's `NotOnOrAfter` value, whichever is shorter. The maximum duration for a session is 1 hour, and the minimum duration is 15 minutes, even if values outside this range are specified. Optionally, you can pass an AWS IAM access policy to this operation. The temporary security credentials that are returned by the operation have the permissions that are associated with the access policy of the role being assumed, except for any permissions explicitly denied by the policy you pass. This gives you a way to further restrict the permissions for the federated user. These policies and any applicable resource-based policies are evaluated when calls to AWS are made using the temporary security credentials. Before your application can call `AssumeRoleWithSAML`, you must configure your SAML identity provider (IdP) to issue the claims required by AWS. Additionally, you must use AWS Identity and Access Management (AWS IAM) to create a SAML provider entity in your AWS account that represents your identity provider, and create an AWS IAM role that specifies this SAML provider in its trust policy. Calling `AssumeRoleWithSAML` does not require the use of AWS 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. For more information, see the following resources: + `Creating Temporary Security Credentials for SAML Federation`_ in the Using Temporary Security Credentials guide. + `SAML Providers`_ in the Using IAM guide. + `Configuring a Relying Party and Claims in the Using IAM guide. `_ + `Creating a Role for SAML-Based Federation`_ in the Using IAM guide. :type role_arn: string :param role_arn: The Amazon Resource Name (ARN) of the role that the caller is assuming. :type principal_arn: string :param principal_arn: The Amazon Resource Name (ARN) of the SAML provider in AWS IAM that describes the IdP. :type saml_assertion: string :param saml_assertion: The base-64 encoded SAML authentication response provided by the IdP. For more information, see `Configuring a Relying Party and Adding Claims`_ in the Using IAM guide. :type policy: string :param policy: An AWS IAM policy in JSON format. The temporary security credentials that are returned by this operation have the permissions that are associated with the access policy of the role being assumed, except for any permissions explicitly denied by the policy you pass. These policies and any applicable resource-based policies are evaluated when calls to AWS are made using the temporary security credentials. The policy must be 2048 bytes or shorter, and its packed size must be less than 450 bytes. :type duration_seconds: integer :param duration_seconds: The duration, in seconds, of the role session. The value can range from 900 seconds (15 minutes) to 3600 seconds (1 hour). By default, the value is set to 3600 seconds. An expiration can also be specified in the SAML authentication response's `NotOnOrAfter` value. The actual expiration time is whichever value is shorter. The maximum duration for a session is 1 hour, and the minimum duration is 15 minutes, even if values outside this range are specified. """ params = { 'RoleArn': role_arn, 'PrincipalArn': principal_arn, 'SAMLAssertion': saml_assertion, } if policy is not None: params['Policy'] = policy if duration_seconds is not None: params['DurationSeconds'] = duration_seconds return self.get_object('AssumeRoleWithSAML', params, AssumedRole, verb='POST') def assume_role_with_web_identity(self, role_arn, role_session_name, web_identity_token, provider_id=None, policy=None, duration_seconds=None): """ Returns a set of temporary security credentials for users who have been authenticated in a mobile or web application with a web identity provider, such as Login with Amazon, Facebook, or Google. `AssumeRoleWithWebIdentity` is an API call that does not require the use of AWS security credentials. Therefore, you can distribute an application (for example, on mobile devices) that requests temporary security credentials without including long-term AWS credentials in the application or by deploying server-based proxy services that use long-term AWS credentials. For more information, see `Creating a Mobile Application with Third-Party Sign-In`_ in AWS Security Token Service . The temporary security credentials 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 AWS service APIs. The credentials are valid for the duration that you specified when calling `AssumeRoleWithWebIdentity`, which can be from 900 seconds (15 minutes) to 3600 seconds (1 hour). By default, the temporary security credentials are valid for 1 hour. The temporary security credentials that are returned from the `AssumeRoleWithWebIdentity` response have the permissions that are associated with the access policy of the role being assumed. You can further restrict the permissions of the temporary security credentials by passing a policy in the request. The resulting permissions are an intersection of the role's access policy and the policy that you passed. These policies and any applicable resource-based policies are evaluated when calls to AWS service APIs are made using the temporary security credentials. 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, see ` Creating Temporary Security Credentials for Mobile Apps Using Third-Party Identity Providers`_. :type role_arn: string :param role_arn: The Amazon Resource Name (ARN) of the role that the caller is assuming. :type role_session_name: string :param role_session_name: 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 web_identity_token: string :param web_identity_token: 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. :type provider_id: string :param provider_id: Specify this value only for OAuth access tokens. Do not specify this value for OpenID Connect ID tokens, such as `accounts.google.com`. This is the fully-qualified host component of the domain name of the identity provider. Do not include URL schemes and port numbers. Currently, `www.amazon.com` and `graph.facebook.com` are supported. :type policy: string :param policy: A supplemental policy that is associated with the temporary security credentials from the `AssumeRoleWithWebIdentity` call. The resulting permissions of the temporary security credentials are an intersection of this policy and the access policy that is associated with the role. Use this policy to further restrict the permissions of the temporary security credentials. :type duration_seconds: integer :param duration_seconds: The duration, in seconds, of the role session. The value can range from 900 seconds (15 minutes) to 3600 seconds (1 hour). By default, the value is set to 3600 seconds. """ params = { 'RoleArn': role_arn, 'RoleSessionName': role_session_name, 'WebIdentityToken': web_identity_token, } if provider_id is not None: params['ProviderId'] = provider_id if policy is not None: params['Policy'] = policy if duration_seconds is not None: params['DurationSeconds'] = duration_seconds return self.get_object( 'AssumeRoleWithWebIdentity', params, AssumedRole, verb='POST' ) def decode_authorization_message(self, encoded_message): """ Decodes additional information about the authorization status of a request from an encoded message returned in response to an AWS request. For example, if a user is not authorized to perform an action that he or she has requested, the request returns a `Client.UnauthorizedOperation` response (an HTTP 403 response). Some AWS actions additionally return an encoded message that can provide details about this authorization failure. Only certain AWS actions return an encoded authorization message. The documentation for an individual action indicates whether that action returns an encoded message in addition to returning an HTTP code. The message is encoded because the details of the authorization status can constitute privileged information that the user who requested the action should not see. To decode an authorization status message, a user must be granted permissions via an IAM policy to request the `DecodeAuthorizationMessage` ( `sts:DecodeAuthorizationMessage`) action. The decoded message includes the following type of information: + Whether the request was denied due to an explicit deny or due to the absence of an explicit allow. For more information, see `Determining Whether a Request is Allowed or Denied`_ in Using IAM . + The principal who made the request. + The requested action. + The requested resource. + The values of condition keys in the context of the user's request. :type encoded_message: string :param encoded_message: The encoded message that was returned with the response. """ params = { 'EncodedMessage': encoded_message, } return self.get_object( 'DecodeAuthorizationMessage', params, DecodeAuthorizationMessage, verb='POST' )