NAME

VM::EC2::Security::Token - Temporary security token object

SYNOPSIS

 use VM::EC2;
 use VM::EC2::Security::Policy
 # under your account
 $ec2 = VM::EC2->new(...);  # as usual
 my $policy = VM::EC2::Security::Policy->new;
 $policy->allow('DescribeImages','RunInstances');
 my $token = $ec2->get_federation_token(-name     => 'TemporaryUser',
                                        -duration => 60*60*3, # 3 hrs, as seconds
                                        -policy   => $policy);
 print $token->sessionToken,"\n";
 print $token->accessKeyId,"\n";
 print $token->secretAccessKey,"\n";
 print $token->federatedUser,"\n";
 my $serialized = $token->credentials->serialize;
 # get the serialized token to the temporary user
 send_data_to_user_somehow($serialized); 
 # under the temporary user's account
 my $serialized = get_data_somehow();
 # create a copy of the token from its serialized form
 my $token = VM::EC2::Security::Credentials->new_from_serialized($serialized);
 # open a new EC2 connection with this token. User will be
 # able to run all the methods specified in the policy.
 my $ec2   = VM::EC2->new(-security_token => $token);
 print $ec2->describe_images(-owner=>'self');
 # convenience routine; will return a VM::EC2 object authorized
 # to use the current token
 my $ec2   = $token->new_ec2;
 print $ec2->describe_images(-owner=>'self');

DESCRIPTION

VM::EC2::Security::Token objects allow you to grant a user access to some or all of your EC2 resources for a limited period of time. The user does not have to have his own AWS account.

Token objects are returned by calls to VM::EC2->get_federation_token() and get_session_token(). The former call is used to create a temporary user with privileges restricted to those listed in the accompanying policy (a VM::EC2::Security::Policy object). The latter call is used in conjunction with multi-factor authentication devices, such as smart cards. The tokens returned by get_session_token() are not associated with a user account nor a policy, and grant privileges to all EC2 actions and resources. Both federation and session tokens have an expiry time between a few seconds and 36 hours.

A VM::EC2::Security::Credentials object contained within the token contains the temporary secret access key, access key ID, and a session token string that unlocks the access key. The credentials object can be serialized into a form suitable for sending to a user via a secure channel, such as SSL or S/MIME e-mail, and unserialized at the receiving end into a copy of the original credentials object.

Either the token object, or its contained credentials object can be used passed to VM::EC2->new() via the -security_token parameter in order to gain access to EC2 resources.

METHODS

 credentials()     -- The VM::EC2::Security::Credentials object
                        that contains the session token, access key ID,
                        and secret key.
 federatedUser()  -- the VM::EC2::Security::FederatedUser object that
                        contains information about the temporary user
                        account.
 packedPolicySize() -- A percentage value indicating the size of the policy in
                         packed form relative to the maximum allowed size. 
                         Policies in excess of 100% will be rejected by the
                         service.
 secret_access_key()-- Convenience method that calls the credentials object's
                        secret_access_key() method.
 access_key_id() --    Convenience method that calls the credentials object's
                        access_key_id() method.
 session_token() --    Convenience method that calls the credentials object's
                        session_token() method.
 new_ec2(@args)  --    Convenience method that returns a VM::EC2 object authorized
                        with the current token. You may pass any of the arguments
                        accepted by VM::EC2->new(), except that -access_key and 
                        -secret_key will be ignored if present.

STRING OVERLOADING

When used in a string context, this object will interpolate as the session token, and can be used for the -security_token parameter in VM::EC2->new().

AUTHOR

Lincoln Stein <lincoln.stein@gmail.com>.

This package and its accompanying libraries is free software; you can redistribute it and/or modify it under the terms of the GPL (either version 1, or at your option, any later version) or the Artistic License 2.0. Refer to LICENSE for the full license text. In addition, please see DISCLAIMER.txt for disclaimers of warranty.

2022-10-14