User configurable password generation for secret engines

Challenge

Vault's secret engines generate passwords that adhere to a default pattern that may not meet the standards required by your applications or within your organization. You may require passwords with:

• Lengths that are smaller or exceed the default length
• Differing character sets
• Frequency of characters
• Positional requirements for characters
• Disallowed repetition
• Disallowed words from a dictionary

Solution

Vault 1.5 introduced support for configurable password generation defined by a password policy. A policy defines the rules and requirements that the password must adhere and can provide that password directly through a new endpoint or within secrets engines.

Secrets engines with support for password policies:

• Active Directory
• Azure
• LDAP
• RabbitMQ
• All Databases

Prerequisites

This lab was tested on macOS using an x86_64 based processor. If you are running macOS on an Apple silicon-based processor, click the Start interactive lab button or perform the steps using a x86_64 based Linux virtual machine in your preferred cloud provider.

• Vault version 1.5 or later; refer to the Vault install guide to install Vault.

• RabbitMQ environment or Docker.

• ngrok installed and configured with auth token (HCP Vault Dedicated only)

Launch Terminal

This tutorial includes a free interactive command-line lab that lets you follow along on actual cloud infrastructure.

Start interactive lab

Lab setup

Start RabbitMQ

RabbitMQ is a message-broker that has a secrets engine that enables Vault to generate user credentials.

In a new terminal, start a RabbitMQ server running on port 15672 that has a user named learn_vault with the password hashicorp.

$ docker run --rm --name some-rabbit -p 15672:15672 \
    -e RABBITMQ_DEFAULT_USER=learn_vault \
    -e RABBITMQ_DEFAULT_PASS=hashicorp \
    rabbitmq:3-management

Docker downloads the necessary images and launches a RabbitMQ database container. RabbitMQ is ready for Vault to generate credentials.

Start Vault

A Vault server is able to generate passwords that meet the requirements of a configurable password policy. These password policies may also be applied to supported secrets engines.

Setup RabbitMQ secrets engine with the default password policy

The RabbitMQ secrets engine generates passwords that adhere to a default password policy.

1. Enable the RabbitMQ secrets engine at the rabbitmq-default-policy path.

   $ vault secrets enable -path rabbitmq-default-policy rabbitmq
   Success! Enabled the rabbitmq secrets engine at: rabbitmq-default-policy/
   

   The secrets engine requires configuration so it can communicate with the RabbitMQ server.

2. Configure the secrets engine to connect to the RabbitMQ server.

   $ vault write rabbitmq-default-policy/config/connection \
       connection_uri=$RABBITMQ_URL \
       username="learn_vault" \
       password="hashicorp"
   

   Output:

   Success! Data written to: rabbitmq-default-policy/config/connection
   

   The secrets engine is configured to talk to the RabbitMQ server running locally over the HTTP management interface. The user, learn_vault, with its password hashicorp, is an administrator that was generated when RabbitMQ started.

3. Create a role named example.

   $ vault write rabbitmq-default-policy/roles/example \
       vhosts='{"/":{"read": ".*", "write": ".*"}}'
   

   Output:

   Success! Data written to: rabbitmq-default-policy/roles/example
   

   The example role defines an endpoint for dynamic credential generation. The credentials generated are granted read and write every entity.

4. Generate credentials from the example role.

   $ vault read rabbitmq-default-policy/creds/example
   

   Example output:

   Key                Value
   ---                -----
   lease_id           rabbitmq-default-policy/creds/example/4yCYMMCZ4I4mKBlPsbNNsKdj
   lease_duration     768h
   lease_renewable    true
   password           v0E6LjTeabrtEAz72cbYINNodWSApPS61vGP
   username           root-2b3482f7-b522-9997-ab0c-1f3057a396d3
   

   The credentials display the username and password generated. The password generated, v0E6LjTeabrtEAz72cbYINNodWSApPS61vGP, adheres to the default password policy for the secrets engine.

Define a password policy

1. Create a policy file named example_policy.hcl.

   $ tee example_policy.hcl <<EOF
   length=20
   
   rule "charset" {
     charset = "abcdefghijklmnopqrstuvwxyz"
     min-chars = 1
   }
   
   rule "charset" {
     charset = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
     min-chars = 1
   }
   
   rule "charset" {
     charset = "0123456789"
     min-chars = 1
   }
   
   rule "charset" {
     charset = "!@#$%^&*"
     min-chars = 1
   }
   EOF
   

   The policy is written in HashiCorp Configuration Language (HCL). The length field sets the length of the password returned to 20 characters. Each rule stanza defines a character set and the minimum number of occurrences those characters need to appear in the generated password. These rules are cumulative so each one adds more requirements on the password generated.

2. Create a Vault password policy named example with the password policy rules defined in example_policy.hcl.

   $ vault write sys/policies/password/example policy=@example_policy.hcl
   Success! Data written to sys/polices/password/example_policy
   

   This policy can now be accessed directly to generate a password or referenced by its name example when configuring supported secrets engines.

3. Generate a password from the example password policy.

   $ vault read sys/policies/password/example/generate
   
   Key         Value
   ---         -----
   password    #v!RQDHxHunJ1TUmCyys
   

   The password generated adheres to the requirements:

   • length of 20 characters
   • at least 1 uppercase character
   • at least 1 lowercase character
   • at least 1 number
   • at least 1 symbol

Setup RabbitMQ secrets engine with a password policy

The RabbitMQ secrets engine may be configured to adopt a password policy.

1. Enable the RabbitMQ secrets engine at the rabbitmq-with-policy path.

   $ vault secrets enable -path rabbitmq-with-policy rabbitmq
   Success! Enabled the rabbitmq secrets engine at: rabbitmq-with-policy/
   

   The secrets engine requires configuration so it can communicate with the RabbitMQ server.

2. Configure the secrets engine to connect to the RabbitMQ server and use the example password policy.

   $ vault write rabbitmq-with-policy/config/connection \
       connection_uri=$RABBITMQ_URL \
       username="learn_vault" \
       password="hashicorp" \
       password_policy="example"
   

   Output:

   Success! Data written to: rabbitmq-with-policy/config/connection
   

   The same connection information is used to establish the connection with the RabbitMQ server. The difference is that the password_policy has been set to the example policy defined in Define a password policy section.

3. Create a role named example.

   $ vault write rabbitmq-with-policy/roles/example \
       vhosts='{"/":{"read": ".*", "write": ".*"}}'
   

   Output:

   Success! Data written to: rabbitmq-with-policy/roles/example
   

   The example role defines an endpoint for dynamic credential generation. The credentials generated are granted read and write on every entity.

4. Generate a login from the example role.

   $ vault read rabbitmq-with-policy/creds/example
   

   Example output:

   Key                Value
   ---                -----
   lease_id           rabbitmq-with-policy/creds/example/vfoht23KclCzOuKzlRYeMZZS
   lease_duration     768h
   lease_renewable    true
   password           HtjHFtdy21*iBpNZjLNb
   username           root-4efd295b-1a4e-285c-14c8-06b135c5464a
   

   The credentials display the username and password generated. The password generated, HtjHFtdy21*iBpNZjLNb, adheres to the example password policy defined in the secrets engine's configuration.

Next steps

You configured a RabbitMQ secrets engine that generated credentials with the default password policy. Learn more about the RabbitMQ secrets engine by reading the documentation and the API documentation.

Then you defined a password policy and generated a password. Learn more about by reading the documentation and the API documentation.

Finally, you configured another RabbitMQ secrets engine that generated credentials that used a custom password policy.