open-vault/website/source/guides/identity/approle-trusted-entities.html.md
Jeff Escalante a3dfde5cec New Docs Website (#5535)
* conversion stage 1

* correct image paths

* add sidebar title to frontmatter

* docs/concepts and docs/internals

* configuration docs and multi-level nav corrections

* commands docs, index file corrections, small item nav correction

* secrets converted

* auth

* add enterprise and agent docs

* add extra dividers

* secret section, wip

* correct sidebar nav title in front matter for apu section, start working on api items

* auth and backend, a couple directory structure fixes

* remove old docs

* intro side nav converted

* reset sidebar styles, add hashi-global-styles

* basic styling for nav sidebar

* folder collapse functionality

* patch up border length on last list item

* wip restructure for content component

* taking middleman hacking to the extreme, but its working

* small css fix

* add new mega nav

* fix a small mistake from the rebase

* fix a content resolution issue with middleman

* title a couple missing docs pages

* update deps, remove temporary markup

* community page

* footer to layout, community page css adjustments

* wip downloads page

* deps updated, downloads page ready

* fix community page

* homepage progress

* add components, adjust spacing

* docs and api landing pages

* a bunch of fixes, add docs and api landing pages

* update deps, add deploy scripts

* add readme note

* update deploy command

* overview page, index title

* Update doc fields

Note this still requires the link fields to be populated -- this is solely related to copy on the description fields

* Update api_basic_categories.yml

Updated API category descriptions. Like the document descriptions you'll still need to update the link headers to the proper target pages.

* Add bottom hero, adjust CSS, responsive friendly

* Add mega nav title

* homepage adjustments, asset boosts

* small fixes

* docs page styling fixes

* meganav title

* some category link corrections

* Update API categories page

updated to reflect the second level headings for api categories

* Update docs_detailed_categories.yml

Updated to represent the existing docs structure

* Update docs_detailed_categories.yml

* docs page data fix, extra operator page remove

* api data fix

* fix makefile

* update deps, add product subnav to docs and api landing pages

* Rearrange non-hands-on guides to _docs_

Since there is no place for these on learn.hashicorp, we'll put them
under _docs_.

* WIP Redirects for guides to docs

* content and component updates

* font weight hotfix, redirects

* fix guides and intro sidenavs

* fix some redirects

* small style tweaks

* Redirects to learn and internally to docs

* Remove redirect to `/vault`

* Remove `.html` from destination on redirects

* fix incorrect index redirect

* final touchups

* address feedback from michell for makefile and product downloads
2018-10-19 08:40:11 -07:00

29 KiB

layout page_title sidebar_title sidebar_current description
guides AppRole With Terraform & Chef - Guides AppRole with Terraform and Chef guides-identity-approle-tf-chef This guide discusses the concepts necessary to help users understand Vault's AppRole authentication pattern and how to use it to securely introduce a Vault authentication token to a target server, application, container, etc.x

Vault AppRole with Terraform and Chef Demo

In the AppRole Pull Authentication guide, the question of how best to deliver the Role ID and Secret ID were brought up, and the role of trusted entities (Terraform, Chef, Nomad, Kubernetes, etc.) was mentioned.

AppRole auth method workflow

This intermediate Vault guide aims to provide a simple, end-to-end example of how to use Vault's AppRole authentication method, along with Terraform and Chef, to address the challenge of the secure introduction of an initial token to a target system.

The purpose of this guide is to provide the instruction to reproduce the working implementation demo introduced in the Delivering Secret Zero: Vault AppRole with Terraform and Chef webinar.

YouTube

-> NOTE: This is a proof of concept and NOT SUITABLE FOR PRODUCTION USE.

Reference Material

Estimated Time to Complete

20 minutes

Challenge

The goal of the AppRole authentication method is to provide a mechanism for the secure introduction of secrets to target systems (servers, applications, containers, etc.).

The question becomes what systems within our environment do we trust to handle or deliver the RoleID and SecretID to our target systems.

Solution

Use Trusted Entities to deliver the AppRole authentication values. For example, use Terraform to deliver your RoleID or embed it into your AMI or Dockerfile. Then you might use Jenkins or Chef to obtain the response-wrapped SecretID and deliver it to the target system.

AppRole allows us to securely introduce the authentication token to the target system by preventing any single system from having full access to an authentication token that does not belong to. This helps us maintain the security principles of least privilege and non-repudiation.

The important thing to note here is that regardless of what systems are considered as Trusted Entities, the same pattern applies.

For example:

Prerequisites

This guide assumes that you are proficient enough to perform basic Terraform tasks. If you are not familiar with Terraform, refer to the online documentation.

The following AWS resources are required to perform this demo:

Download demo assets

Clone or download the demo assets from the hashicorp/vault-guides GitHub repository to perform the steps described in this guide.

The following assets can be found in the repository:

  • Chef cookbook (/chef/cookbooks): A sample cookbook with a recipe that installs NGINX and demonstrates Vault Ruby Gem functionality used to interact with Vault APIs.
  • Terraform configurations (/terraform-aws):
    • /terraform-aws/mgmt-node: Configuration to set up a management server running both Vault and Chef Server, for demo purposes.
    • /terraform-aws/chef-node: Configuration to set up a Chef node and bootstrap it with the Chef Server, passing in Vault's AppRole RoleID and the appropriate Chef run-list.
  • Vault configuration (/scripts): Data scripts used to configure the appropriate mounts and policies in Vault for this demo.

Steps

The scenario in this guide uses Terraform and Chef as trusted entities to deliver RoleID and SecretID.

AppRole auth method workflow

For the simplicity of the demonstration, both Vault and Chef are installed on the same node. Terraform provisions the node which contains the RoleID as an environment variable. Chef pulls the SecretID from Vault.

Provisioning for this demo happens in 2 phases:

Phase 1: Provision our Vault & Chef Server

Step 1: Provision the Vault and Chef Server

This provides a quick and simple Vault and Chef Server configuration to help you get started.

NOTE: This is done for demonstration purpose and NOT a recommended practice for production.

In this phase, you use Terraform to spin up a server (and associated AWS resources) with both Vault and Chef Server installed. Once this server is up and running, you'll complete the appropriate configuration steps in Vault to set up our AppRole and tokens for use in the demo.

~> If using Terraform Enterprise, create a Workspace for this repo and set the appropriate Terraform/Environment variables using the terraform.tfvars.example file as a reference. Follow the instructions in the documentation to perform the appropriate setup in Terraform Enterprise.

Using Terraform Open Source:

Task 1: Change the working directory (cd) to identity/vault-chef-approle/terraform-aws/mgmt-node.

.
├── main.tf
├── outputs.tf
├── templates
│   └── userdata-mgmt-node.tpl
├── terraform.tfvars.example
└── variables.tf

Task 2: Update the terraform.tfvars.example file to match your account and rename it to terraform.tfvars.

At minimum, replace the following variable with appropriate values:

  • s3_bucket_name
  • vpc_id
  • subnet_id
  • key_name
  • ec2_pem

NOTE: If your VPC, subnet and EC2 key pair were created on a region other than us-east-1, be sure to set the aws_region value to match your chosen region.

Task 3: Perform a terraform init to pull down the necessary provider resources. Then terraform plan to verify your changes and the resources that will be created. If all looks good, then perform a terraform apply to provision the resources. The Terraform output will display the public IP address to SSH into your server.

$ terraform init
Initializing provider plugins...
...
Terraform has been successfully initialized!


$ terraform plan
...
Plan: 5 to add, 0 to change, 0 to destroy.


$ terraform apply
...
Apply complete! Resources: 5 added, 0 changed, 0 destroyed.

Outputs:
vault-public-ip = 192.0.2.0

The Terraform output will display the public IP address to SSH into your server.

For example:

$ ssh -i "/path/to/EC2/private_key.pem" ubuntu@192.0.2.0

Task 4: Initial setup of the Chef server takes several minutes. Once you can SSH into your mgmt server, run tail -f /var/log/tf-user-data.log to see when the initial configuration is complete.

$ tail -f /var/log/tf-user-data.log

When you see the following message, the initial setup is complete.

+ echo '2018/03/27 21:53:06 /var/lib/cloud/instance/scripts/part-001: Complete'

You can find the following subfolders in your home directory:

  • /home/ubuntu/vault-chef-approle-demo: root of our project
  • /home/ubuntu/vault-chef-approle-demo/chef: root of our Chef app; this is where our knife configuration is located (.chef/knife.rb)
  • /home/ubuntu/vault-chef-approle-demo/scripts: there's a vault-approle-setup.sh script located here to help automate the setup of Vault, or you can follow along in the rest of this README to configure Vault manually

Step 2: Initialize and Unseal Vault

Before moving on, set your working environment variables in your mgmt server:

$ export VAULT_ADDR=http://127.0.0.1:8200
$ export VAULT_SKIP_VERIFY=true

Before you can do anything in Vault, you need to initialize and unseal it. Perform one of the following:

Step 3: AppRole Setup

First, initialize and unseal the Vault server using a shortcut.

~> This is a convenient shortcut for demo. DO NOT DO THIS IN PRODUCTION!!!

Refer to the online documentation for initializing and unsealing Vault for more details.

# Initialize the Vault server and write out the unseal keys and root token into files
$ curl --silent
       --request PUT \
       --data '{"secret_shares": 1, "secret_threshold": 1}' \
       ${VAULT_ADDR}/v1/sys/init | tee \
       >(jq -r .root_token > /home/ubuntu/vault-chef-approle-demo/root-token) \
       >(jq -r .keys[0] > /home/ubuntu/vault-chef-approle-demo/unseal-key)

# Unseal vault
$ vault operator unseal $(cat /home/ubuntu/vault-chef-approle-demo/unseal-key)

# Set the root token to VAULT_TOKEN env var
$ export VAULT_TOKEN=$(cat /home/ubuntu/vault-chef-approle-demo/root-token)

In the next few steps, you will create a number of policies and tokens within Vault. Below is a table that summarizes them:

Policy Description Token Attachment
app-1-secret-read Sets the policy for the final token that will be delivered via the AppRole login None. This will be delivered to the client upon AppRole login
app-1-approle-roleid-get Sets the policy for the token that you'll give to Terraform to deliver the RoleID (only) roleid-token
terraform-token-create The Terraform Vault provider doesn't use the token supplied to it directly. This is to prevent the token from being exposed in Terraform's state file. Instead, the Token given to Terraform needs to have the capability to create child tokens with short TTLs. See [here] (https://www.terraform.io/docs/providers/vault/index.html#token) for more info roleid-token
app-1-approle-secretid-create Sets the policy for the token that you'll store in the Chef Data Bag. This will only be able to pull our AppRole's SecretID secretid-token

These setups only need to be performed upon initial creation of an AppRole, and would typically be done by a Vault administrator.

Now that you have your Vault server unsealed, you can begin to set up necessary policies, AppRole auth method, and tokens.

Task 1: Set up our AppRole policy

This is the policy that will be attached to secret zero which you are delivering to our application (app-1).

API call using cURL

# Policy to apply to AppRole token
$ tee app-1-secret-read.json <<EOF
{"policy":"path \"secret/app-1\" {capabilities = [\"read\", \"list\"]}"}
EOF

# Create the app-1-secret-read policy in Vault
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request PUT \
       --data @app-1-secret-read.json \
       $VAULT_ADDR/v1/sys/policy/app-1-secret-read

**CLI command**
# Policy to apply to AppRole token
$ tee app-1-secret-read.hcl <<EOF
path "secret/app-1" {
  capabilities = ["read", "list"]
}
EOF

# Create the app-1-secret-read policy in Vault
$ vault policy write app-1-secret-read app-1-secret-read.hcl

Task 2: Enable the AppRole authentication method

API call using cURL

# Payload for invoking sys/auth API endpoint
$ tee approle.json <<EOF
{
  "type": "approle",
  "description": "Demo AppRole auth method"
}
EOF

# Enable AppRole auth backend
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request POST \
       --data @approle.json \
       $VAULT_ADDR/v1/sys/auth/approle

**CLI command**
$ vault auth enable -description="Demo AppRole auth method" approle

Task 3: Configure the AppRole

Now, you are going to create an AppRole role named, app-1.

API call using cURL

# Payload containing AppRole auth method configuration
# TTL is set to 10 minutes, and Max TTL to be 30 minutes
$ tee app-1-approle-role.json <<EOF
{
    "role_name": "app-1",
    "bind_secret_id": true,
    "secret_id_ttl": "10m",
    "secret_id_num_uses": "1",
    "token_ttl": "10m",
    "token_max_ttl": "30m",
    "period": 0,
    "policies": [
        "app-1-secret-read"
    ]
}
EOF

# AppRole backend configuration
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request POST \
       --data @app-1-approle-role.json \
       $VAULT_ADDR/v1/auth/approle/role/app-1

**CLI command**
# TTL is set to 10 minutes, and Max TTL to be 30 minutes
$ vault write auth/approle/role/app-1 policies="app-1-secret-read" token_ttl="10m" token_max_ttl="30m"

Step 4: Configure Tokens for Terraform and Chef

Now, you're ready to configure the policies and tokens to Terraform and Chef to interact with Vault. Remember, the point here is that you are giving each system a limited token that is only able to pull either the RoleID or SecretID, but not both.

AppRole auth method workflow

Task 1: Create a policy and token for Terraform

Create a token with appropriate policies allowing Terraform to pull the RoleID from Vault:

API call using cURL

# Policy file granting to retrieve RoleID from Vault
$ tee app-1-approle-roleid-get.hcl <<EOF
{"policy":"path \"auth/approle/role/app-1/role-id\" {capabilities = [\"read\"]}"}
EOF

# Create the app-1-approle-roleid-get policy in Vault
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request PUT \
       --data @app-1-approle-roleid-get.hcl \
       $VAULT_ADDR/v1/sys/policy/app-1-approle-roleid-get

# For Terraform
# See: https://www.terraform.io/docs/providers/vault/index.html#token
# Policy granting to create tokens required by Terraform
$ tee terraform-token-create.hcl <<EOF
{"policy":"path \"/auth/token/create\" {capabilities = [\"update\"]}"}
EOF

# Create the app-1-approle-roleid-get policy in Vault
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request PUT \
       --data @terraform-token-create.hcl \
       $VAULT_ADDR/v1/sys/policy/terraform-token-create

# Payload to configure token for Terraform to pull RoleID
$ tee roleid-token-config.json <<EOF
{
  "policies": [
    "app-1-approle-roleid-get",
    "terraform-token-create"
  ],
  "meta": {
    "user": "terraform-demo"
  },
  "ttl": "720h",
  "renewable": true
}
EOF

# Get token and save it in roleid-token.json
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request POST \
       --data @roleid-token-config.json \
       $VAULT_ADDR/v1/auth/token/create > roleid-token.json

The token and associated metadata will be written out to the file roleid-token.json. The client_token value is what you'll give to Terraform. The file should look similar to the following:

$ cat roleid-token.json | jq
{
  "request_id": "2e1d05eb-988d-4cf7-7b6a-d2668de31536",
  "lease_id": "",
  "renewable": false,
  "lease_duration": 0,
  "data": null,
  "wrap_info": null,
  "warnings": null,
  "auth": {
    "client_token": "6a7ad093-42ab-885e-3d67-6d51a5583da6",
    "accessor": "f6170506-ee0f-5a59-8478-e0aac2d3259f",
    "policies": [
      "app-1-approle-roleid-get",
      "default",
      "terraform-token-create"
    ],
    "metadata": {
      "user": "terraform-demo"
    },
    "lease_duration": 2592000,
    "renewable": true,
    "entity_id": ""
  }
}

**CLI command**
# Policy file granting to retrieve RoleID from Vault
$ tee app-1-approle-roleid-get.hcl <<EOF
path "auth/approle/role/app-1/role-id" {
  capabilities = [ "read" ]
}
EOF

# Create the app-1-approle-roleid-get policy in Vault
$ vault policy write app-1-approle-roleid-get app-1-approle-roleid-get.hcl

# For Terraform
# See: https://www.terraform.io/docs/providers/vault/index.html#token
# Policy granting to create tokens required by Terraform
$ tee terraform-token-create.hcl <<EOF
path "auth/token/create" {
  capabilities = [ "update" ]
}
EOF

# Create the app-1-approle-roleid-get policy in Vault
$ vault policy write terraform-token-create terraform-token-create.hcl

# Get token and save it in roleid-token.txt
$ vault token create -policy="app-1-approle-roleid-get" -policy="terraform-token-create" \
      -metadata="user"="terraform-user" > roleid-token.txt

The token and associated metadata will be written out to the file roleid-token.txt. The token value is what you'll give to Terraform. The file should look similar to the following:

$ cat roleid-token.txt
Key                Value
---                -----
token              2600aeda-6385-c163-7171-543b1e1fabcf
token_accessor     6ef835e3-4948-8c61-1e89-3625ca31fd84
token_duration     768h
token_renewable    true
token_policies     [app-1-approle-roleid-get default terraform-token-create]
token_meta_user    terraform-demo

Task 2: Create a policy and token for Chef

Create a token with appropriate policies allowing Chef to pull the SecretID from Vault:

API call using cURL

# Policy file granting to retrieve SecretID
$ tee app-1-approle-secretid-create.hcl <<EOF
{"policy":"path \"auth/approle/role/app-1/secret-id\" {capabilities = [\"update\"]}"}
EOF

# Create the app-1-approle-secretid-create policy in Vault
$ curl --silent \
    --location \
    --header "X-Vault-Token: $VAULT_TOKEN" \
    --request PUT \
    --data @app-1-approle-secretid-create.hcl \
    $VAULT_ADDR/v1/sys/policy/app-1-approle-secretid-create

# Payload to invoke auth/token/create endpoint
$ tee secretid-token-config.json <<EOF
{
  "policies": [
    "app-1-approle-secretid-create"
  ],
  "meta": {
    "user": "chef-demo"
  },
  "ttl": "720h",
  "renewable": true
}
EOF

# Get token for Chef to get SecretID from Vault and store it in secretid-token.json
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request POST \
       --data @secretid-token-config.json \
       $VAULT_ADDR/v1/auth/token/create > secretid-token.json

The resulting file should look like this:

$ cat secretid-token.json | jq
{
  "request_id": "6f6ad8a1-fedb-b838-60ce-87999f01aff6",
  "lease_id": "",
  "renewable": false,
  "lease_duration": 0,
  "data": null,
  "wrap_info": null,
  "warnings": null,
  "auth": {
    "client_token": "cdfdb7a0-d7a6-3769-927d-0ace297726ea",
    "accessor": "88e8aaca-1584-4881-3368-d9cb5cd7ddae",
    "policies": [
      "app-1-approle-secretid-create",
      "default"
    ],
    "metadata": {
      "user": "chef-demo"
    },
    "lease_duration": 2592000,
    "renewable": true,
    "entity_id": ""
  }
}

**CLI command**
# Policy file granting to retrieve SecretID
$ tee app-1-approle-secretid-create.hcl <<EOF
path "auth/approle/role/app-1/secret-id" {
  capabilities = [ "update" ]
}
EOF

# Create the app-1-approle-secretid-create policy in Vault
$ vault policy write app-1-approle-secretid-create app-1-approle-secretid-create.hcl

# Get token for Chef to get SecretID from Vault and store it in secretid-token.txt
$ vault token create -policy="app-1-approle-secretid-create" \
      -metadata="user"="chef-demo" > secretid-token.txt

The resulting file should look like this:

$ cat secretid-token.txt
Key                Value
---                -----
token              20d69183-59cb-c953-6dea-34f5f1bbe5f7
token_accessor     a17e7a43-c14a-b96a-0014-9149d218e74a
token_duration     768h
token_renewable    true
token_policies     [app-1-approle-secretid-create default]
token_meta_user    chef-demo

Step 5: Save the Token in a Chef Data Bag

At this point, you have a client token generated for Terraform and another for Chef server to log into Vault. For the sake of simplicity, you can put the Chef's client token (secretid-token.json) in a Data Bag which is fine because this token can only retrieve SecretID from Vault which is not much of a use without a corresponding RoleID.

Now, create a Chef Data Bag and put the SecretID token (secretid-token.json) along with the rest of its metadata.

$ cd /home/ubuntu/vault-chef-approle-demo/chef/

# Use the path for where you created this file in the previous step
# You're just adding an 'id' field to the file as that's a required field for data bags
$ cat /home/ubuntu/secretid-token.json | jq --arg id approle-secretid-token '. + {id: $id}' > secretid-token.json

$ knife data bag create secretid-token

$ knife data bag from file secretid-token secretid-token.json

$ knife data bag list

$ knife data bag show secretid-token

$ knife data bag show secretid-token approle-secretid-token

The last step should show the following output:

$ knife data bag show secretid-token approle-secretid-token
WARNING: Unencrypted data bag detected, ignoring any provided secret options.
auth:
  accessor:       88e8aaca-1584-4881-3368-d9cb5cd7ddae
  client_token:   cdfdb7a0-d7a6-3769-927d-0ace297726ea
  entity_id:
  lease_duration: 2592000
  metadata:
  policies:
    app-1-approle-secretid-create
    default
  renewable:      true
data:
id:             approle-secretid-token
lease_duration: 0
lease_id:
renewable:      false
request_id:     6f6ad8a1-fedb-b838-60ce-87999f01aff6
warnings:
wrap_info:

Step 6: Write Secrets

Let's write some test data in the secret/app-1 path so that the target app will have some secret to retrieve from Vault at a later step.

API call using cURL

# Write some demo secrets
$ tee demo-secrets.json <<'EOF'
{
  "username": "app-1-user",
  "password": "$up3r$3cr3t!"
}
EOF

$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request POST \
       --data @demo-secrets.json \
       $VAULT_ADDR/v1/secret/app-1

# Verify that you can read back the data:
$ curl --silent \
       --location \
       --header "X-Vault-Token: $VAULT_TOKEN" \
       --request GET \
       $VAULT_ADDR/v1/secret/app-1 | jq
{
  "request_id": "1f73c7ee-27fa-bad0-9c77-b330eef1ea88",
  "lease_id": "",
  "renewable": false,
  "lease_duration": 2764800,
  "data": {
    "password": "$up3r$3cr3t!",
    "username": "app-1-user"
  },
  "wrap_info": null,
  "warnings": null,
  "auth": null
}

**CLI command**
# Write some demo secrets
$ vault write secret/app-1 username="app-1-user" password="\$up3r\$3cr3t!"

# Verify that you can read back the data:
$ vault read secret/app-1
Key                 Value
---                 -----
refresh_interval    768h
password            $up3r$3cr3t!
username            app-1-user

-> At this point, just about all the pieces are in place. Remember, these setup steps will only need to be performed upon initial creation of an AppRole, and would typically be done by a Vault administrator.

Phase 2: Provision our Chef Node to Show AppRole Login

To complete the demo, run the chef-node Terraform configuration to see how everything talks to each other.

Task 1: Change the working directory

Open another terminal on your host machine (not the mgmt-node) and cd into the identity/vault-chef-approle/terraform-aws/chef-node directory:

$ cd identity/vault-chef-approle/terraform-aws/chef-node

Task 2: Update terraform.tfvars.example

Replace the variable values in terraform.tfvars.example to match your environment and save it as terraform.tfvars like you have done at Step 1.

Note the following:

  • Update the vault_address and chef_server_address variables with the IP address of our mgmt-node from above.
  • Update the vault_token variable with the RoleID token from Task 1 in Step 4.
    • If you ran the demo-setup.sh script (Option 1), retrieve the client_token in the /home/ubuntu/vault-chef-approle-demo/roleid-token.json file:
$ cat ~/vault-chef-approle-demo/roleid-token.json | jq ".auth.client_token"

Task 3: Run Terraform

Perform a terraform init to pull down the necessary provider resources. Then terraform plan to verify your changes and the resources that will be created. If all looks good, then perform a terraform apply to provision the resources.

The Terraform output will display the public IP address to SSH into your server.

NOTE: If the terraform apply fails with "io: read/write on closed pipe" error, this is a known issue with Terraform 0.11.4 and 0.11.5. Please try again with another Terraform version.

At this point, Terraform will perform the following actions:

  • Pull a RoleID from our Vault server
  • Provision an AWS instance
  • Write the RoleID to the AWS instance as an environment variable
  • Run the Chef provisioner to bootstrap the AWS instance with our Chef Server
  • Run our Chef recipe which will install NGINX, perform our AppRole login, get our secrets, and output them to our index.html file

AppRole auth method workflow

The Chef recipe can be found at identity/vault-chef-approle/chef/cookbooks/vault_chef_approle_demo/recipes/default.rb.

...
# Configure address for Vault Gem
Vault.address = ENV['VAULT_ADDR']

# Get AppRole RoleID from our environment variables (delivered via Terraform)
var_role_id = ENV['APPROLE_ROLEID']

# Get Vault token from data bag (used to retrieve the SecretID)
vault_token_data = data_bag_item('secretid-token', 'approle-secretid-token')

# Set Vault token (used to retrieve the SecretID)
Vault.token = vault_token_data['auth']['client_token']

# Get AppRole SecretID from Vault
var_secret_id = Vault.approle.create_secret_id('app-1').data[:secret_id]
...

Task 4: Verification

Once Terraform completes the apply operation, it will output the public IP address of our new server. You can plug that IP address into a browser to see the output. It should look similar to the following:

Role ID:
f6286b97-246e-9fb4-4d9f-0c9465451851

Secret ID:
72f4b60c-26d0-d947-5026-153943174831

AppRole Token:
d11d81e4-0ba1-fefc-03f8-e5f06793b60d

Read Our Secrets:
{:password=>"$up3r$3cr3t!", :username=>"app-1-user"}

Additional References

The following is a curated list of webinars, blogs and GitHub repositories that add additional context to fill out the concepts discussed in the webinar and demonstrated in the code:

Next Steps

Watch the video recording of the Delivering Secret Zero: Vault AppRole with Terraform and Chef webinar which talks about the usage of AppRole with Terraform and Chef as its trusted entities.