saml2aws

README

saml2aws

CLI tool which enables you to login and retrieve AWS temporary credentials using SAML with ADFS or PingFederate Identity Providers.

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:

• Setup an account alias, either using the default or given a name
• Prompt user for credentials
• Log in to Identity Provider 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

• Identity Provider
  • ADFS (2.x or 3.x)
  • PingFederate + PingId
  • Okta + (Duo, SMS, TOTP)
  • KeyCloak + (TOTP)
• AWS SAML Provider configured

Caveats

Aside from Okta, most of the providers in this project are using screen scraping to log users into SAML, this isn't ideal and hopefully vendors make this easier in the future. In addition to this there are some things you need to know:

1. AWS only permits session tokens being issued with a duration of up to 3600 seconds (1 hour), this is constrained by the STS AssumeRoleWithSAML API call and DurationSeconds field.
2. Every SAML provider is different, the login process, MFA support is pluggable and therefore some work may be needed to integrate with your identity server

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).
      --verbose                Enable verbose logging
      --version                Show application version.
  -a, --idp-account="default"  The name of the configured IDP account
  -p, --profile="saml"         The AWS profile to save the temporary credentials
  -s, --skip-verify            Skip verification of server certificate.
      --hostname=HOSTNAME      The hostname of the SAML IDP server used to login.
      --username=USERNAME      The username used to login.
      --password=PASSWORD      The password used to login.
      --role=ROLE              The ARN of the role to assume.
      --skip-prompt            Skip prompting for parameters during login.

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.


  configure
    Configure a new IDP account.

Install

OSX

If you're on OSX you can install saml2aws using homebrew!

brew tap versent/homebrew-taps
brew install saml2aws

Windows

If you're on Windows you can install saml2aws using chocolatey!

choco install saml2aws
saml2aws --version

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, note the credentials will be overwritten when you first login and are supplied to unsure ~/.aws/credentials file is created.

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

Then your ready to use saml2aws.

Example

Log into a service.

$ saml2aws login
Using IDP Account default to access Ping https://id.example.com
To use saved password just hit enter.
Username [mark.wolfe@example.com]:
Password: ************

Authenticating as mark.wolfe@example.com ...
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/wolfeidau@example.com

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).

Building

To build this software on osx clone to the repo to $GOPATH/src/github.com/versent/saml2aws and ensure you have $GOPATH/bin in your $PATH.

If you don't have glide installed you can install it using homebrew.

brew install glide

Then to build the software just run.

make

Install the binary to $GOPATH/bin.

make install

To release run.

make release

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
• go-ntlmssp NTLM/Negotiate authentication

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.

Documentation

Index

• Variables
• func AssignPrincipals(awsRoles []*AWSRole, awsAccounts []*AWSAccount)
• func ExtractAwsRoles(data []byte) ([]string, error)
• func PromptForConfigurationDetails(idpAccount *cfg.IDPAccount) error
• func PromptForLoginDetails(loginDetails *creds.LoginDetails) error
• type AWSAccount
  • func ExtractAWSAccounts(data []byte) ([]*AWSAccount, error)
  • func ParseAWSAccounts(samlAssertion string) ([]*AWSAccount, error)
• type AWSRole
  • func LocateRole(awsRoles []*AWSRole, roleName string) (*AWSRole, error)
  • func ParseAWSRoles(roles []string) ([]*AWSRole, error)
  • func PromptForAWSRoleSelection(accounts []*AWSAccount) (*AWSRole, error)
• type ConfigLoader
  • func NewConfigLoader(profile string) *ConfigLoader
  • func (p *ConfigLoader) LoadHostname() (string, error)
  • func (p *ConfigLoader) LoadProvider(defaultValue string) (string, error)
  • func (p *ConfigLoader) LoadUsername() (string, error)
  • func (p *ConfigLoader) SaveHostname(hostname string) error
  • func (p *ConfigLoader) SaveProvider(provider string) error
  • func (p *ConfigLoader) SaveUsername(username string) error
• type ErrMissingElement
  • func (e ErrMissingElement) Error() string
• type ProviderList
  • func (mfbp ProviderList) Mfas(provider string) []string
  • func (mfbp ProviderList) Names() []string
• type SAMLClient
  • func NewSAMLClient(idpAccount *cfg.IDPAccount) (SAMLClient, error)

Variables

var (
	// ErrConfigHomeNotFound returned when a user home directory can't be located.
	ErrConfigHomeNotFound = errors.New("user home directory not found")

	// ErrConfigFileNotFound returned when the required aws credentials file doesn't exist.
	ErrConfigFileNotFound = errors.New("aws credentials file not found")
)

var (
	ErrMissingAssertion = ErrMissingElement{Tag: assertionTag}
)

ErrMissingAssertion indicates that an appropriate assertion element could not be found in the SAML Response

var MFAsByProvider = ProviderList{
	"ADFS":      []string{"None", "VIP"},
	"ADFS2":     []string{"None"},
	"Ping":      []string{"Auto"},
	"JumpCloud": []string{"None"},
	"Okta":      []string{"Auto"},
	"KeyCloak":  []string{"Auto"},
}

MFAsByProvider a list of providers with their respective supported MFAs

Functions

func AssignPrincipals

func AssignPrincipals(awsRoles []*AWSRole, awsAccounts []*AWSAccount)

AssignPrincipals assign principal from roles

func ExtractAwsRoles

func ExtractAwsRoles(data []byte) ([]string, error)

ExtractAwsRoles given an assertion document extract the aws roles

func PromptForConfigurationDetails

func PromptForConfigurationDetails(idpAccount *cfg.IDPAccount) error

PromptForConfigurationDetails prompt the user to present their hostname, username and mfa

func PromptForLoginDetails

func PromptForLoginDetails(loginDetails *creds.LoginDetails) error

PromptForLoginDetails prompt the user to present their username, password and hostname

Types

type AWSAccount

type AWSAccount struct {
	Name  string
	Roles []*AWSRole
}

AWSAccount holds the AWS account name and roles

func ExtractAWSAccounts

func ExtractAWSAccounts(data []byte) ([]*AWSAccount, error)

ExtractAWSAccounts extract the accounts from the AWS html page

func ParseAWSAccounts

func ParseAWSAccounts(samlAssertion string) ([]*AWSAccount, error)

ParseAWSAccounts extract the aws accounts from the saml assertion

type AWSRole

type AWSRole struct {
	RoleARN      string
	PrincipalARN string
	Name         string
}

AWSRole aws role attributes

func LocateRole

func LocateRole(awsRoles []*AWSRole, roleName string) (*AWSRole, error)

LocateRole locate role by name

func ParseAWSRoles

func ParseAWSRoles(roles []string) ([]*AWSRole, error)

ParseAWSRoles parses and splits the roles while also validating the contents

func PromptForAWSRoleSelection

func PromptForAWSRoleSelection(accounts []*AWSAccount) (*AWSRole, error)

PromptForAWSRoleSelection present a list of roles to the user for selection

type ConfigLoader

type ConfigLoader struct {
	Filename string
	Profile  string
}

ConfigLoader loads config options

func NewConfigLoader

func NewConfigLoader(profile string) *ConfigLoader

NewConfigLoader helper to create the config

func (*ConfigLoader) LoadHostname

func (p *ConfigLoader) LoadHostname() (string, error)

LoadHostname load the hostname

func (*ConfigLoader) LoadProvider

func (p *ConfigLoader) LoadProvider(defaultValue string) (string, error)

LoadProvider load the provider

func (*ConfigLoader) LoadUsername

func (p *ConfigLoader) LoadUsername() (string, error)

LoadUsername load the username

func (*ConfigLoader) SaveHostname

func (p *ConfigLoader) SaveHostname(hostname string) error

SaveHostname persist the hostname

func (*ConfigLoader) SaveProvider

func (p *ConfigLoader) SaveProvider(provider string) error

SaveProvider persist the provider

func (*ConfigLoader) SaveUsername

func (p *ConfigLoader) SaveUsername(username string) error

SaveUsername persist the username

type ErrMissingElement

type ErrMissingElement struct {
	Tag, Attribute string
}

ErrMissingElement is the error type that indicates an element and/or attribute is missing. It provides a structured error that can be more appropriately acted upon.

func (ErrMissingElement) Error

func (e ErrMissingElement) Error() string

type ProviderList

type ProviderList map[string][]string

ProviderList list of providers with their MFAs

func (ProviderList) Mfas

func (mfbp ProviderList) Mfas(provider string) []string

Mfas retrieve a sorted list of mfas from the provider list

func (ProviderList) Names

func (mfbp ProviderList) Names() []string

Names get a list of provider names

type SAMLClient

type SAMLClient interface {
	Authenticate(loginDetails *creds.LoginDetails) (string, error)
}

SAMLClient client interface

func NewSAMLClient

func NewSAMLClient(idpAccount *cfg.IDPAccount) (SAMLClient, error)

NewSAMLClient create a new SAML client