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Nike-Inc / gimme-aws-creds

A CLI that utilizes Okta IdP via SAML to acquire temporary AWS credentials
Apache License 2.0
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Gimme AWS Creds

gimme-aws-creds is a CLI that utilizes an Okta IdP via SAML to acquire temporary AWS credentials via AWS STS.

Okta is a SAML identity provider (IdP), that can be easily set-up to do SSO to your AWS console. Okta does offer an OSS java CLI tool to obtain temporary AWS credentials, but I found it needs more information than the average Okta user would have and doesn't scale well if have more than one Okta App.

With gimme-aws-creds all you need to know is your username, password, Okta url and MFA token, if MFA is enabled. gimme-aws-creds gives you the option to select which Okta AWS application and role you want credentials for. Alternatively, you can pre-configure the app and role name by passing -c or editing the config file. This is all covered in the usage section.

Disclaimer

Okta is a registered trademark of Okta, Inc. and this tool has no affiliation with or sponsorship by Okta, Inc.

Prerequisites

Okta SAML integration to AWS using the AWS App

Python 3.7+

A Note on Python 3.10+ Compatibility on Windows

gimme-aws-creds depends on the ctap-keyring-device library for WebAuthn support. All of the released versions of ctap-keyring-device require winRT on Windows, which only works on Python 3.9 and lower and is no longer maintained. Until a version of ctap-keyring-device that supports winSDK (the replacement for winRT) is released to PyPi, or some other solution is found, WebAuthn support will not be available for people running Python 3.10+ on Windows.

Optional

Gimme-creds-lambda can be used as a proxy to the Okta APIs needed by gimme-aws-creds. This removes the requirement of an Okta API key. Gimme-aws-creds authenticates to gimme-creds-lambda using OpenID Connect and the lambda handles all interactions with the Okta APIs. Alternately, you can set the OKTA_API_KEY environment variable and the gimme_creds_server configuration value to 'internal' to call the Okta APIs directly from gimme-aws-creds.

Installation

This is a Python 3 project.

Install/Upgrade from PyPi:

pip3 install --upgrade gimme-aws-creds

OR

Install/Upgrade the latest gimme-aws-creds package direct from GitHub:

pip3 install --upgrade git+git://github.com/Nike-Inc/gimme-aws-creds.git

OR

Install the gimme-aws-creds package if you have already cloned the source:

python -m pip install .

OR

Use homebrew

brew install gimme-aws-creds

OR

Use with nix flakes

# flake.nix
# Use by running `nix develop`
{
  description = "Shell example";

  inputs.flake-utils.url = "github:numtide/flake-utils";
  inputs.nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
  inputs.gimme-aws-creds.url = "github:Nike-Inc/gimme-aws-creds";

  outputs = {
    self,
    nixpkgs,
    flake-utils,
    gimme-aws-creds,
    ...
  } @ inputs:
    flake-utils.lib.eachDefaultSystem
    (
      system: let
        pkgs = nixpkgs.legacyPackages.${system};
      in {
        devShells.default = pkgs.mkShell {
          packages = [pkgs.bash gimme-aws-creds.defaultPackage.${system}];
        };
      }
    );
}

OR

Use with original nix

# shell.nix
# Use by running `nix-shell`
{pkgs ? import <nixpkgs> {}, ...}:
with pkgs; let
  gimme-src = fetchgit {
    name = "gimme-aws-creds";
    url = "https://github.com/Nike-Inc/gimme-aws-creds";
    branchName = "master";
    sha256 = "<replace>"; #nix-prefetch-url --unpack https://github.com/Nike-Inc/gimme-aws-creds/archive/master.tar.gz
  };

  gimme-aws-creds = import gimme-src;
in
  mkShell rec {
    name = "gimme-aws-creds";

    buildInputs = [
      bash
      (gimme-aws-creds.default)
    ];
  }

OR

Build the docker image locally:

docker build -t gimme-aws-creds .

To make it easier you can also create an alias for the gimme-aws-creds command with docker:

# make sure you have the "~/.okta_aws_login_config" locally first!
touch ~/.okta_aws_login_config && \
alias gimme-aws-creds="docker run -it --rm \
  -v ~/.aws/credentials:/root/.aws/credentials \
  -v ~/.okta_aws_login_config:/root/.okta_aws_login_config \
  gimme-aws-creds"

With this config, you will be able to run further commands seamlessly!

Command Auto Completion

If you are using Bash or Zsh, you can add autocompletion for the gimme-aws-creds commandline options and profile names. To add the autocomplete config, add the following to the end of your .bashrc or .zshrc:

.bashrc

INSTALL_DIR=$(dirname $(which gimme-aws-creds))
source ${INSTALL_DIR}/gimme-aws-creds-autocomplete.sh"

.zshrc

INSTALL_DIR=$(dirname $(which gimme-aws-creds))
autoload bashcompinit
bashcompinit
source ${INSTALL_DIR}/gimme-aws-creds-autocomplete.sh

Using gimme-aws-creds with Okta Identity Engine

There are two options for using gimme-aws-creds with an OIE domain:

Okta Identity Engine and Device Authorization Flow

This is the recommended method for authentication with OIE. It matches the flow used by Okta's AWS client. When using gimme-aws-creds with the Device Authorization flow, you will authenticate using your browser. Storing credentials in keychain or passing MFA codes through the command-line is NOT POSSIBLE.

To use gimme-aws-creds with an Okta Identity Engine (OIE) domain, you must create a new OIDC Native Application and connect it to your AWS integration app(s).

The OIDC Native Application requires Grant Types Authorization Code, Device Authorization , and Token Exchange. These settings are in the Okta Admin UI at Applications > [the OIDC app] > General Settings > Grant type.

The pairing with the AWS Federation Application is achieved in the Fed app's Sign On Settings. These settings are in the Okta Admin UI at Applications > [the AWS Fed app] > Sign On. Make sure to set the Allowed Web SSO Client value to the Client ID of the OIDC Native Application. Repeat that setting for each AWS application you want to access with gimme-aws-creds.

Finally, set the Client ID in gimme-aws-creds (gimme-aws-creds --action-configure or update the client_id parameter in your config file)

Make sure to use the same authentication policy for both the AWS Federation Application and the OIDC application ( or at least use equivalent policy rules for both). If not, you'll receive a 400 Bad Request response when requesting the Web SSO token.

Forcing the use of the Okta Classic login flow

The login flow used in Okta Classic currently still works with Okta Identity Engine domains, BUT there are a couple caveats:

Configuration

To set-up the configuration run:

gimme-aws-creds --action-configure

You can also set up different Okta configuration profiles, this is useful if you have multiple Okta accounts or environments you need credentials for. You can use the configuration wizard or run:

gimme-aws-creds --action-configure --profile profileName

A configuration wizard will prompt you to enter the necessary configuration parameters for the tool to run, the only one that is required is the okta_org_url. The configuration file is written to ~/.okta_aws_login_config, but you can change the location with the environment variable OKTA_CONFIG.

Configuration File

The config file follows a configfile format. By default, it is located in $HOME/.okta_aws_login_config

Example file:

[myprofile]
client_id = myclient_id

Configurations can inherit from other configurations to share common configuration parameters.

[my-base-profile]
client_id = myclient_id
[myprofile]
inherits = my-base-profile
aws_rolename = my-role

Usage

If you are not using gimme-creds-lambda nor using appurl settings, make sure you set the OKTA_API_KEY environment variable.

After running --action-configure, just run gimme-aws-creds. You will be prompted for the necessary information.

$ ./gimme-aws-creds
Username: user@domain.com
Password for user@domain.com:
Authentication Success! Calling Gimme-Creds Server...
Pick an app:
[ 0 ] AWS Test Account
[ 1 ] AWS Prod Account
Selection: 1
Pick a role:
[ 0 ]: OktaAWSAdminRole
[ 1 ]: OktaAWSReadOnlyRole
Selection: 1
Multi-factor Authentication required.
Pick a factor:
[ 0 ] Okta Verify App: SmartPhone_IPhone: iPhone
[ 1 ] token:software:totp: user@domain.com
Selection: 0
Okta Verify push sent...
export AWS_ACCESS_KEY_ID=AQWERTYUIOP
export AWS_SECRET_ACCESS_KEY=T!#$JFLOJlsoddop1029405-P

You can automate the environment variable creation by running $(gimme-aws-creds) on linux or gimme-aws-creds | iex using Windows Powershell

You can run a specific configuration profile with the --profile parameter:

./gimme-aws-creds --profile profileName

The username and password you are prompted for are the ones you login to Okta with. You can predefine your username by setting the OKTA_USERNAME environment variable or using the -u username parameter.

If you have not configured an Okta App or Role, you will prompted to select one.

If all goes well you will get your temporary AWS access, secret key and token, these will either be written to stdout or ~/.aws/credentials.

You can always run gimme-aws-creds --help for all the available options.

Alternatively, you can overwrite values in the config section with environment variables for instances where say you may want to change the duration of your token. A list of values of to change with environment variables are:

Example: GIMME_AWS_CREDS_CLIENT_ID='foobar' AWS_DEFAULT_DURATION=12345 gimme-aws-creds

For changing variables outside of this, you'd need to create a separate profile altogether with gimme-aws-creds --action-configure --profile profileName

Viewing Profiles

gimme-aws-creds --action-list-profiles will go to your okta config file and print out all profiles created and their settings.

Viewing roles

gimme-aws-creds --action-list-roles will print all available roles to STDOUT without retrieving their credentials.

Credential expiration time

Writing to the AWS credentials file will include the x_security_token_expires value in RFC3339 format. This allows tools to validate if the credentials are expiring or are expiring soon and warn the user or trigger a refresh.

Generate credentials as json

gimme-aws-creds -o json will print out credentials in JSON format - 1 entry per line

Store credentials from json

gimme-aws-creds --action-store-json-creds will store JSON formatted credentials from stdin to aws credentials file, eg: gimme-aws-creds -o json | gimme-aws-creds --action-store-json-creds. Data can be modified by scripts on the way.

Usage in python code

Configuration and interactions can be configured using gimme_aws_creds.ui, UserInterfaces support all kind of interactions within library including: asking for input, sys.argv and os.environ overrides.

import sys
import gimme_aws_creds.main
import gimme_aws_creds.ui

account_ids = sys.argv[1:] or [
  '123456789012',
  '120123456789',
]

pattern = "|".join(sorted(set(account_ids)))
pattern = '/:({}):/'.format(pattern)
ui = gimme_aws_creds.ui.CLIUserInterface(argv=[sys.argv[0], '--roles', pattern])
creds = gimme_aws_creds.main.GimmeAWSCreds(ui=ui)

# Print out all selected roles:
for role in creds.aws_selected_roles:
    print(role)

# Generate credentials overriding profile name with `okta-<account_id>`
for data in creds.iter_selected_aws_credentials():
    arn = data['role']['arn']
    account_id = None
    for piece in arn.split(':'):
        if len(piece) == 12 and piece.isdigit():
            account_id = piece
            break

    if account_id is None:
        raise ValueError("Didn't find aws_account_id (12 digits) in {}".format(arn))

    data['profile']['name'] = 'okta-{}'.format(account_id)
    creds.write_aws_creds_from_data(data)

MFA security keys support

gimme-aws-creds works both on FIDO1 enabled org and WebAuthN enabled org

Note that FIDO1 will probably be deprecated in the near future as standards moves forward to WebAuthN

WebAuthN support is available for usb security keys (gimme-aws-creds relies on the yubico fido2 lib).

To use your local machine as an authenticator, along with Touch ID or Windows Hello, if available, you must register a new authenticator via gimme-aws-creds, using:

gimme-aws-creds --action-setup-fido-authenticator

Then, you can choose the newly registered authenticator from the factors list.

Running Tests

You can run all the unit tests using pytest. Most of the tests are mocked.

pytest -vv tests

Maintenance

This project is maintained by Eric Pierce

Thanks and Credit

I came across okta_aws_login written by Joe Keegan, when I was searching for a CLI tool that generates AWS tokens via Okta. Unfortunately it hasn't been updated since 2015 and didn't seem to work with the current Okta version. But there was still some great code I was able to reuse under the MIT license for gimme-aws-creds. I have noted in the comments where I used his code, to make sure he receives proper credit.

Etc

okta-aws-cli

okta-aws-cli-assume-role

AWS - How to Implement Federated API and CLI Access Using SAML 2.0 and AD FS

Contributing

License

Gimme AWS Creds is released under the Apache License, Version 2.0