pilgrim2go/saml2aws

CLI tool which enables you to login and retrieve AWS temporary credentials using SAML with ADFS 3.x

saml2aws

CLI tool which enables you to login and retrieve AWS temporary credentials using SAML with ADFS 3.x.

This is based on python code from How to Implement a General Solution for Federated API/CLI Access Using SAML 2.0.

The process goes something like this:

• Prompt user for credentials
• Log in to ADFS using form based authentication
• Build a SAML assertion containing AWS roles
• Exchange the role and SAML assertion with AWS STS service to get a temporary set of credentials
• Save these creds to an aws profile named "saml"

Requirements

• ADFS 3.x
• AWS SAML Provider configured

Usage

usage: saml2aws [<flags>] <command> [<args> ...]

A command line tool to help with SAML access to the AWS token service.

Flags:
      --help            Show context-sensitive help (also try --help-long and --help-man).
  -p, --profile="saml"  The AWS profile to save the temporary credentials
  -s, --skip-verify     Skip verification of server certificate.
      --version         Show application version.

Commands:
  help [<command>...]
    Show help.


  login
    Login to a SAML 2.0 IDP and convert the SAML assertion to an STS token.


  exec [<command>...]
    Exec the supplied command with env vars from STS token.

install

If your on OSX you can install saml2aws using homebrew!

brew tap versent/homebrew-taps
brew install saml2aws

Setup

Install the AWS CLI see https://docs.aws.amazon.com/cli/latest/userguide/installing.html, in our case we are using homebrew on OSX.

brew install awscli

Configure an empty default profile with your region of choice.

$ aws configure
AWS Access Key ID [None]:
AWS Secret Access Key [None]:
Default region name [None]: us-west-2
Default output format [None]:

Then your ready to use saml2aws.

Example

Log into a service.

$ saml2aws login
Hostname [id.example.com]:
Username [[email protected]]:
Password: ************

ADFS https://id.example.com
Authenticating to ADFS...
Please choose the role you would like to assume:
[ 0 ]:  arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSBuild
[ 1 ]:  arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSNonProd
Selection: 1
Selected role: arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSNonProd
Requesting AWS credentials using SAML assertion
Saving credentials
Logged in as: arn:aws:sts::123123123123:assumed-role/AWS-Admin-CloudOPSNonProd/[email protected]

Your new access key pair has been stored in the AWS configuration
Note that it will expire at 2016-09-19 15:59:49 +1000 AEST
To use this credential, call the AWS CLI with the --profile option (e.g. aws --profile saml ec2 describe-instances).

Run ansible with an expired token present, exec verifies the token and requests login.

$ saml2aws exec --skip-verify -- ansible-playbook -e "aws_region=ap-southeast-2" playbook.yml
Hostname [id.example.com]:
Username [[email protected]]:
Password: ************

ADFS https://id.example.com
Authenticating to ADFS...
Please choose the role you would like to assume:
[ 0 ]:  arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSBuild
[ 1 ]:  arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSNonProd
Selection: 1
Selected role: arn:aws:iam::123123123123:role/AWS-Admin-CloudOPSNonProd
Requesting AWS credentials using SAML assertion
Saving credentials
Logged in as: arn:aws:sts::123123123123:assumed-role/AWS-Admin-CloudOPSNonProd/[email protected]

Your new access key pair has been stored in the AWS configuration
Note that it will expire at 2016-09-19 15:59:49 +1000 AEST
To use this credential, call the AWS CLI with the --profile option (e.g. aws --profile saml ec2 describe-instances).

PLAY [create cloudformation stack] *************************************************

...

PLAY RECAP *********************************************************************
localhost                  : ok=2    changed=0    unreachable=0    failed=0

environment vars

The exec sub command will export the following environment variables.

• AWS_ACCESS_KEY_ID
• AWS_SECRET_ACCESS_KEY
• AWS_SESSION_TOKEN
• AWS_SECURITY_TOKEN
• EC2_SECURITY_TOKEN

Dependencies

This tool would not be possible without some great opensource libraries.

• goquery html querying
• etree xpath selector
• kingpin command line flags
• aws-sdk-go AWS Go SDK
• go-ini INI file parser

License

This code is Copyright (c) 2015 Versent and released under the MIT license. All rights not explicitly granted in the MIT license are reserved. See the included LICENSE.md file for more details.